Letteratura scientifica selezionata sul tema "Helicobacter pylori"

SUMMARY Helicobacters other than Helicobacter pylori have been associated with gastritis, gastric ulcers, and gastric mucosa-associated lymphoid tissue lymphoma in humans. These very fastidious microorganisms with a typical large spiral-shaped morphology were provisionally designated “H. heilmannii,” but in fact they comprise at least five different Helicobacter species, all of which are known to colonize the gastric mucosa of animals. H. suis, which has been isolated from the stomachs of pigs, is the most prevalent gastric non-H. pylori Helicobacter species in humans. Other gastric non-H. pylori helicobacters colonizing the human stomach are H. felis, H. salomonis, H. bizzozeronii, and the still-uncultivable “Candidatus Helicobacter heilmannii.” These microorganisms are often detected in the stomachs of dogs and cats. “Candidatus Helicobacter bovis” is highly prevalent in the abomasums of cattle but has only occasionally been detected in the stomachs of humans. There are clear indications that gastric non-H. pylori Helicobacter infections in humans originate from animals, and it is likely that transmission to humans occurs through direct contact. Little is known about the virulence factors of these microorganisms. The recent successes with in vitro isolation of non-H. pylori helicobacters from domestic animals open new perspectives for studying these microorganisms and their interactions with the host.

The types of helicobacter which are found in the stomachs of carnivorous pets, especially cats, have been traditionally referred to as ‘gastric helicobacter-like organisms’ (GHLOs). These are microaerophilic, Gram-negative, spiral bacteria with multiple terminal flagellae and are endowed with high-level urease activity which allows them to survive in an acidic environment. Certain species have one or more periplasmic fibrils. The two GHLOs most commonly found in cats are Helicobacter felis and a species related to H heilmannii which was recently cultured from dogs. All phenotypic and genotypic (16S RNA gene sequences) evidence suggests that both of these bacteria belong in the genus Helicobacter. Whether or not helicobacters can be transmitted to humans from carnivorous pets is controversial but the recent discovery of H pylori-infected cats may be evidence of an animal reservoir for this pathogen. Although the role of H pylori in inducing antral gastritis and perpetuating pyloric ulcers in humans is well established, whether or not Helicobacter spp are causally involved in any feline gastric inflammatory conditions is unknown.

With the exponential increase in research in the field ofHelicobacter pyloria paradigm shift has occurred. It is now recognized thatH pyloriis a chronic infection of the stomach causing inflammation. Some patients remain asymptomatic, while others may develop dyspepsia, duodenal or gastric ulcer, gastric cancer or a mucosa-associated lymphoid tissue lymphoma. However, the role ofH pyloriin contributing to nonulcer dyspepsia or nonsteroidal anti-inflammatory drug gastropathy remains controversial. An effective vaccine againstH pyloriis years away. Major interest has focused on the questions "who should be investigated and therefore treated" and "what is the latest gold standard for eradication ofH pylori"? In Europe, guidelines have been developed to help the practitioner answer these important questions. Canadian guidelines will soon be available. For persons with known peptic ulcer disease there should be unequivocal acceptance that the good clinical practice of eradicatingH pyloriwill result in substantial savings in health care expenses. The original 'classical triple therapy' (bismuth, metronidazole and tetracycline [BMT]) has now been surpassed by the combination of a proton pump inhibitor (PPI) plus two antibiotics (metronidazole plus clarithromycin; amoxicillin plus clarithromycin; or amoxicillin plus metronidazole), each given twice a day for one week. In Canada, the regimen of omeprazole plus one antibiotic (amoxicillin or clarithromycin) was approved recently but gives an eradication rate that is lower than the current target of 90%. According to the European (Mäastricht) recommendations, if a single treatment attempt with PPI plus two antibiotics fails, PPI plus BMT is recommended.

AbstrakFaktor risiko infeksi Helicobacter pylori adalah tinggal di negara berkembang, kondisi sosial ekonomi yang rendah, jumlah anggota keluarga yang banyak, etnik dan genetik. Tatalaksana dan diagnosis Helicobacter pylori belum memuaskan karena adanya resistensi antibiotik pada pasien Helicobacter pylori. Kami melaporkan seorang pasien perempuan usia 8 tahun 6 bulan yang terinfeksi Helicobacter pylori. Diagnosis ditegakkan berdasarkan anamnesis, pemeriksaan fisik, dan hasil laboratorium. Pasien diduga terinfeksi Helicobacter pylori karena mengalami nyeri perut berulang. Dari laboratorium didapatkan serologi IgG Helicobacter pylori positif. Pada hasil endoskopi biopsi ditemukan kuman Helicobacter pylori. Pasien mendapat therapi eradikasi lini pertama untuk infeksi Helicobacter pylori yaitu amoksisilin, klaritromisin dan omeprazol selama dua minggu. Setelah dua minggu pengobatan keluhan pasien tidak ada.Kata kunci: Helicobacter pylori, anak, nyeri perut berulangAbstractRisk factors for acquiring Helicobacter pylori infection include residency of developing country, poor socioeconomic conditions, crowded family, and possibly an ethnic or genetic as predispositions. The diagnosis and management Helicobacter pylori has not been satisfied yet, however, there is problem of increasing resistancy antibiotic due to Helicobacter pylori. Objective: We report a 8 year and 6 month old girl who suffered from Helicobacter pylori. The diagnosis was based on history, clinical finding, and laboratory work-up. Suspicion on the presence of Helicobacter pylori was started when the girl had recurrent abdominal pain. Serology IgG Helicobacter pylori was positive and we had done endoscopic examination and biopsy. Therapy this patient was first line eradication Helicobacter pylori which give amoxicillin, clarithromycin and omeprazole for two weeks. There are no sympthoms after two weeks therapyKey word: Helicobacter pylori, children, recurrent abdominal painLAPORAN KASUS

Helicobacter pylori (H. pylori) infection causes chronic gastritis, peptic ulcers and gastric cancer. Although H. pylori prevalence is decreasing worldwide, regional variations exist in Europe, with the lowest infection prevalence in Northern Europe, and the highest in Eastern and Southern Europe (1). Changes in the treatment recommendations and the increasing available evidence have justified the implementation of new recommendations since last Belgian consensus in 1998 (2). Several non-H. pylori Helicobacter species (NH.PYLORI-H), colonizing the stomach of domestic animals, also have the ability to cause gastric disease in humans, although to a lesser extent. These zoonotic NH. PYLORIH are not the subject of the current recommendations.

Background: Helicobacter pylori infection is characterized by an inflammatory infiltrate that might be an important antecedent of gastric cancer. The purpose of this study was to evaluate whether interleukin (IL)-17 inflammation is elicited by gastric T cells in Helicobacter pylori patients with gastric intestinal metaplasia and dysplasia (IM/DYS). We also investigated the serum IL-17A levels in Helicobacter pylori patients with gastric intestinal metaplasia and dysplasia, and patients with Helicobacter pylori non-atrophic gastritis (NAG). Methods: the IL-17 cytokine profile of gastric T cells was investigated in six patients with IM/DYS and Helicobacter pylori infection. Serum IL-17A levels were measured in 45 Helicobacter pylori-infected IM/DYS patients, 45 Helicobacter pylori-infected patients without IM/DYS and in 45 healthy controls (HC). Results: gastric T cells from all IM/DYS patients with Helicobacter pylori were able to proliferate in response to Helicobacter pylori and to produce IL-17A. The Luminex analysis revealed that IL-17A levels were significantly increased in Helicobacter pylori IM/DYS patients compared to healthy controls and to Helicobacter pylori gastritis patients without IM/DYS (452.34 ± 369.13 pg/mL, 246.82 ± 156.06 pg/mL, 169.26 ± 73.82 pg/mL, respectively; p < 0.01, p < 0.05). Conclusions: the results obtained indicate that Helicobacter pylori is able to drive gastric IL-17 inflammation in IM/DYS Helicobacter pylori-infected patients, and that IL-17A serum levels are significantly increased in Helicobacter pylori-infected patients with IM/DYS.

Background: Nasal polyposis is an inflammatory condition of unknown etiology. Recently concern regarding GER orHelicobacter pylori as a possible pathologic cause of nasal polyps has been increasing. The present study was planned to investigate thepresence of Helicobacter Pylor in Nassal polyps by PCR , rapid Urease test and serology. Design: Case control study. Setting: ENT ward ofShiraz, Khalilli Hospital, Iran. Period: April 2006 to March 2008. Materials and Methods: 37 patients with nasal polyps who had undergonenasal endoscopic sinus surgery and 38 control subjects who had undergone septoplasty and turbinectomy. Biopsy specimens of nasal polypsand inferior turbinates were assessed by PCR and Rapid Urease test. Blood sample of both study and control subjects were evaluated for antiH.pylori Ig G by ELISA. HP status was regarded as positive, if 2 tests were positive. Results: Seropositivity was more common in the patientswith nasal polyps (72.97%) than in the control patients (31.57%) (P-value= 0.000) RUT was positive in 9 (24.3%) of 37 patients with nasalpolyps, but was not positive in control group (P-value= 0.001). only 3 of (8.1%) of 37 patients with nasal polyps were positive for both RUT andELISA (P-value =0.115). PCR was negative in all patients and controls. Conclusions: Polypoid tissue can be colonized by some other agentscontaining a urease enzyme other than Helicobacer Pylori. So, result of RUT can be false positive, and addition test may be performed. In theour study by using PCR , we were not able to confirm presence of Helicobacter pylori in the nasal polyps. However, further epidemiologic studiesusing different and specific diagnostic tests with control of documented GER is recommended.

Objective: To determine the frequency of H. pylori infection in dyspeptic patients undergoing endoscopy at a tertiary care centerin Karachi. Data source: Patients undergoing endoscopy at Liaquat National Hospital, Karachi. Design of study: Cross sectional descriptivestudy. Setting: Department of Gastroenterology, Liaquat National Hospital, Karachi. Period: May 2008–October 2008. Material andmethods: All adult patients with symptoms of dyspepsia for more than 1 month duration were included. Patients with upper gastrointestinalbleed, anemia or weight loss were excluded. Upper gastrointestinal endoscopy was performed in all patients and biopsy specimens two eachfrom antrum and body and one from fundus were taken for histology. Results: A total of 123 dyspeptic patients were included in the study. 76(61.8%) patients were males and 47 (38.2%) were females. H pylori was detected in mucosa of 49 (39.8%) patients. The mean age of thepatients was 41.41 ± 13.15 Years (95%CI; 39.06 to 43.75). Rate of H.pylori infection was not found statistical significant with age, gender,duration of symptoms and BMI. Conclusions: The prevalence of H pylori infection in dyspeptic patients was lower than reported in previousstudies from other centers in Pakistan. Other environmental factors should be evaluated in every patient especially who is negative for H. pyloriin our setup.

ABSTRACT Nuclear factor κB (NF-κB) plays a key regulatory role in host cell responses to Helicobacter pylori infection in humans. Although mice are routinely used as a model to study H. pylori pathogenesis, the role of NF-κB in murine cell responses to helicobacters has not been studied in detail. We thus investigated the abilities of different Helicobacter isolates to induce NF-κB-dependent responses in murine gastric epithelial cells (GECs) and in transgenic mice harboring an NF-κB-responsive lacZ reporter gene. H. pylori and Helicobacter felis strains up-regulated the synthesis in mouse GECs of the NF-κB-dependent chemokines KC (CXCL1) and MIP-2 (CXCL2). These responses were cag pathogenicity island (cagPAI) independent and could be abolished by pretreatment with a pharmacological inhibitor of NF-κB. Consistent with the in vitro data, experimental Helicobacter infection of transgenic mice resulted in increased numbers of GECs with nuclear β-galactosidase activity, which is indicative of specific NF-κB activation. The numbers of β-galactosidase-positive cells in mice were significantly increased at day 1 postinoculation with wild-type H. pylori strains harboring or not harboring a functional cagPAI, compared to naive animals (P = 0.007 and P = 0.04, respectively). Strikingly, however, no differences were observed in the levels of gastric NF-κB activation at day 1 postinoculation with H. felis or at day 30 or 135 postinoculation with H. pylori. This work demonstrates for the first time the induction of NF-κB activation within gastric mucosal cells during acute H. pylori infection. Furthermore, the data suggest that helicobacters may be able to regulate NF-κB signaling during chronic infection.

Helicobacter pylori is a gram-negative bacterium which causes chronic gastritis and plays important roles in peptic ulcer disease, gastric carcinoma, and gastric lymphoma. H. pylori has been found in the stomachs of humans in all parts of the world. In developing countries, 70 to 90% of the population carries H. pylori. In developed countries, the prevalence of infection is lower. There appears to be no substantial reservoir of H. pylori aside from the human stomach. Transmission can occur by iatrogenic, fecal-oral, and oral-oral routes. H. pylori is able to colonize and persist in a unique biological niche within the gastric lumen. All fresh isolates of H. pylori express significant urease activity, which appears essential to the survival and pathogenesis of the bacterium. A variety of tests to diagnose H. pylori infection are now available. Histological examination of gastric tissue, culture, rapid urease testing, DNA probes, and PCR analysis, when used to test gastric tissue, all require endoscopy. In contrast, breath tests, serology, gastric juice PCR, and urinary excretion of [15N]ammonia are noninvasive tests that do not require endoscopy. In this review, we highlight advances in the detection of the presence of the organism and methods of differentiating among types of H. pylori, and we provide a background for appropriate chemotherapy of the infection.

O Helicobacter pylori (HP) constitui uma entidade fundamental quando nos reportamos à patologia gastro-duodenal. As indicações para a erradicação desta bactéria constituem, actualmente, uma das grandes controvérsias na área da Gastroenterologia. Com o objectivo principal de estabelecer o actual ponto de situação no que diz respeito às indicações para a erradicação do HP, realizámos uma revisão sistemática aprofundada do tema com base em artigos científicos de boa qualidade metodológica. Existem duas indicações inequívocas para efectuar o tratamento de erradicação do HP: a doença péptica ulcerosa e o linfoma MALT gástrico de baixo grau. Apesar da grande e continuada investigação nesta área, persistem ainda algumas dúvidas relativamente a determinadas situações clínicas em que o HP está envolvido como agente patogénico. São elas a dispepsia funcional, a doença de refluxo gastroesofágico e a utilização concomitante de anti-inflamatórios não esteróides. Nos doentes com anemia por deficiência de ferro inexplicada ou com púrpura trombocitopénica idiopática, recomenda-se que a infecção por HP seja investigada e tratada.

From 1994, Helicobacter pylori was classified by WHO (World Health Organization) as a class I carcinogen and its infection has been associated to gastroduodenal disease. It colonizes more than half of worldwide population, with a prevalent infection rate in developed countries. In spite of the majority of infected people are asymptomatic, around 20% develop severe pathologies like peptic ulcers and the 1% lymphoma of the mucosa-associated lymphoid tissue (MALT) and stomach cancer. This significant epidemiological study both of the unique characteristics of H. pylori inspired many scientists, as bacteriologist, gastroenterologists, cancer and pharmaceutical scientists to understand physio-pathological aspects of this bacterium, and also microbiologist, taxonomist, microbial ecologist and molecular biologist, for a more detailed molecular approach. H. pylori, a Gram negative, microaerophilic bacteria that colonize human gastric mucosa. It is not an acidophilus bacterium and even if the stomach lumen presents inhospitable condition for most microbes, it is able to survive for a short period, sufficient to enter in the highly viscous mucosa, reach gastric epithelium, and colonize the gastro-enteric tract. H. pylori colonization is mediated by a predominant virulence factor, the flagellar motility associated to chemotaxis. To avoid its discharge in the intestinal tract by peristalsis, the bacteria establish a persistent infection inside the viscous gastric mucus film that covers the gastric epithelium. A nickel containing enzyme, the urease, hydrolyzes the urea present in the stomach to ammonia and CO2, buffering the pH of the periplasm. The most severe clinical outcomes are always associated to cag+ strains. cag-PAI is defined as the “Cytotoxic Associated Genes Pathogenicity Island” and it consists of a characteristic chromosome, flanked by transposable elements. Another important virulent factor is the vacuolating cytotoxin A, known as VacA, which induces the formation of large cytoplasmic vacuoles in gastric cultured cell lines. Moreover the iron and nickel acquisition is essential grow factors and a large number of genes are responsible of this mechanism. While the development of an efficient vaccine against H. pylori is now the aim of many researchers, the search for new specific antibiotics as a new pharmaceutical target is required for the complete eradication of H. pylori. In this thesis has been investigate the structural and function role of different pathogenic proteins involved in the H. pylori colonization of human gastric mucosa. These potential drug targets have been cloned, 8 out of 11 were expressed in a heterologous expression system, after purification, 2 of them generate protein crystals and only one was possible to characterize the molecular structure. In particular it has been elucidated a possible physiological role of CeuE (HP1561), a Class III SPB (Substrate Binding Protein), crystalized with Ni(His)2 complex and it was determined its affinity to the complex by an in vitro approach. The H. pylori flagella play a key role during infection allowing the bacterium to move through the mucous layer. The H. pylori hook scaffolding protein FlgD were cloned, expressed, purified and crystalized. A study of other purified pathogenic H. pylori factors belonging to flagellar component apparatus and transcriptional factors involved in cellular stress response has been reported. To obtain these results, different experimental approaches has been used. Bioinformatics analysis of target proteins has been performed to predict the best candidates for a crystallographic study and for genetic construction design. Molecular cloning in plasmid vectors has been performed from PCR amplification. The expression conditions were optimized and performed in E. coli, a heterologous system. The solubility of recombinant proteins were checked and obtained also with protein refolding methods. Different purification techniques were used in order to obtain pure protein. Target characterization was performed due analytical gel filtration, UV spectroscopy, DLS (Dynamic Light Scattering) and CD (Circular Dichroism). The proteins were concentrated to crystallization trials. The protein crystals obtained were analyzed at ESRF synchrotron (Grenoble, France). Functional in vitro approaches were performed using fluorescence spectroscopy, SPR (Surface Plasmon Resonance) and Mass spectroscopy. In the second chapter is described the three dimensional structure of a H. pylori pathogenic protein crystalized in presence with its possible physiological substrate. HP1561 (CeuE) is a H. pylori protein predicted to be an ABC transporter component, periplasmic iron-bind transporter. Recently it was published that CeuE and fecDE genes of H. mustelae encode for a nickel and cobalt acquisition system. In Gram-negative bacteria, nickel uptake is guaranteed by multiple and complex systems that operate at the membrane and periplasmic level. H. pylori employs other yet uncharacterized systems to import the nickel required for the maturation of key enzymes, such as urease and hydrogenase. To understand this contradiction of the data about Ni2+ acquisition system in H. pylori CeuE was cloned, expressed, purified, crystallized and its structure determined. Identity between the sequences of the two Helicobacter is 44%. The two Histidine residues (H103 and H197), potentially involved in Siderophores/Ni2+ binding coordination in H. pylori CeuE, are partially conserved. The His corresponding to H. pylori position 103 is conserved, whilst His197 is replaced by a Leucine. In order to check, if this substitution influence the binding of siderophores/Ni2+, the mutant of H. pylori CeuE H197L was than produced and purified. The crystal structure of H. pylori CeuE has been determined at 1.65Å resolution using the SAD method, in Apo-form and in complex with Ni(His)2. It comprises two structurally similar globular domains, each consisting of a central five-stranded β-sheet surrounded by α-helices, an arrangement commonly classified as a Rossmann-like fold. Structurally, H. pylori CeuE belongs to the class III periplasmic substrate-binding protein. Crystallographic data, fluorescence binding assays and SPR analysis allow to exclude a role of the protein in the transport of VitB12, heme, enterobactin and isolated Ni2+ ions. On the contrary, the crystal structure of the protein/Ni(L-His)2 complex and dissociation constant obtained by SPR technique suggests that H. pylori CeuE binds and transport nickel in vivo thanks to the formation of a Ni2+/histidine complex or to some ligand that mimics it. In the third chapter is presented the study of FlgD, a flagellar component involved in the formation the extracellular complex, the flagellar hook. The motility of H. pylori is considered a colonization factor, due the fact that less motile strains are less able to colonize or survive in the host than full motile strains. In the flagellum machinery are involved more than 50 genomic genes for regulation and assembly. The three major components are the filament, the hook and the basal body. FlgD is not present when the flagellum is completed, but plays a key role during the assembly. Therefore, it has been classified as the hook-scaffolding protein, considering it also as the hook capping protein, interacting with FlgL and FlgK and the basal body rod – modification protein. In H. pylori G27 strain FlgD correspond to the gene hp0858 that was amplified from purified genomic DNA and cloned in an expression plasmid vector. The protein was produced in E. coli BL21 in reach medium ad it resulted to a soluble protein. DLS and analytical gel filtration confirm the oligomeric state of FlgD that resulted to be a tetramer in solution. The protein was concentrated to 30g/l and crystalized after a couple of month of incubation. The crystals had diffracted at 2.7Å of maximum resolution. For molecular replacement approach was used homology modeling. Different molecular models were built to fit experimental diffraction data. The secondary structure of the generated models was fitted with experimental CD spectra, where FlgD resulted to have around 12% of helices and 45% of β-sheets (190-260nm). Crystallographic statistics do not properly converged to a positive molecular refinement with the tested models. To solve FlgD structure are necessary crystals of recombinant Selenomethionine FlgD that was expressed, purified and crystalized. In the fourth chapter are reported H. pylori pathogenic proteins that had been characterized. These proteins could be divided in two groups, the first one of flagellar proteins and the second of cellular stress response factors, in collaboration with Professor V. Scarlato of the department of Biology of Bologna University. FliN is a cytosolic protein, localized in the C ring of the flagellar basal body. It interacts with the other two components FliM and FliG. Missense or mutation of fliN had been associated to non-motile strains. It has been reported that regulates the clockwise/counterclockwise switching of flagella. H. pylori FliN was cloned, expressed and purified from the inclusion body after refolding. Oligomerization after refolding was tested by DLS and analytical gel filtration. The protein resulted to be poly-disperse in solution and no protein crystals have been obtained. FliD is the filament capping protein and it was observed that interact with FliT that is not only a flagellar type III substrate specific export chaperone but also inhibits the expression of fliD thought its specific interaction with the master regulator FlhD4C2 complex. In order to analyze possible structure of the co-crystalized FliD-FliT, it was plan to co-express these proteins. Both were cloned with a different affinity purification system, but only FliT was possible to express and purify from inclusion bodies. The CD spectra presented a strong β-sheet component in the secondary structure. DLS and analytical gel filtration revealed that this protein is poly-disperse in solution and no protein crystals were be obtained. FlgN is a type III secretion chaperone and it has been reported to interact with the two hook junction protein FlgK and FlgL preventing the protein proteolysis when the flagellum is not assembled. These proteins have been cloned in different type of plasmid vectors for a co-expression experiment, but only FlgN was properly expressed in E. coli. Recombinant FlgN was purified by Ni-IMAC and resulted to be soluble in solution. The protein was characterized by analytical gel filtration, DLS and CD. The protein resulted to be a monomer in solution with a 30% of not defined secondary structure (190-260nm). FlgN was concentrated and different crystallization conditions were tested. In the latter group there are three proteins related to Heat shock response, produced when bacteria encounter stress such as the elevated temperatures, ethanol, H2O2 and acid. It was demonstrated that H. pylori Hsps play an important role during the host infection. HrcA and HspR are negative repressor of groESL and dnaK machinery. HrcA activity depends by the presence of HspR, because it is demonstrated that HrcA is not able to bind DNA in absence of HspR. These two proteins were expressed in E. coli and purified by Ni-IMAC affinity. During the concentration step, these proteins present a solubility limit influenced by the concentration. Mutagenesis of a Cys in HspR and detergent solubility screening with HrcA has been performed, but no suitable protein for crystallization trials has been obtained. Hp1026 is a gene present in the same operon of HspR (hp1025). The function of this gene has not been reported. From sequence homology was possible to identify a helicase domain and ATP-binding domain. This protein, ORF, has been expressed in E. coli and purified by Ni-IMAC affinity. Analytical gel filtration and CD has been performed to characterize this protein. The protein was a dimer in solution with a 35% of α-helices component. Crystallization trials have been performed at different protein concentrations and also in presence of its possible cofactor, ATPγS. No crystals have been obtained in tested condition. Appendix: Structural and functional study on a human protease S1P/ SKI1 The study of human S1P/SKI1 protease was performed in collaboration with Professor S. Kunz of the Institute of Microbiology, University Hospital Center and university of Lausanne, Switzerland. S1P/SKI-1 is a serine protease that belongs to the mammalian family of Proprotein Convertases (PC). The aim of this family member is to mediate the activation of different important substrates for cell live. Among these proteases, S1P has been shown to have unique substrate specificity, preferring cleavage after non-basic amino acids. Known S1P cellular targets are SREBP-2, involved in the biosynthesis and uptake of lipids and cholesterol, BDNF, ATF-6 and the surface glycoprotein of viruses belonging to the family of Arenaviridae. S1P is 118 kDa multi-domain protein; two regions of S1P have been investigated, the "Prodomain", involved in the regulation of S1P catalytic activity, and the so called "catalytic domain", which include the residues responsible for the cleavage reaction itself. Moreover it was analyzed an inactive mutant of cS1P: H249A. Also for ProD was chosen one constructs (ProD_AB and ProD_AC) involved in the affinity of the protease substrate. Hence, the sequences corresponding to the domains were synthesized as optimized genes for the expression in E. coli and sub-cloned in expression plasmids in order to obtain C-term His-tagged fusion proteins. These constructs have been expressed in E. coli, purified by Ni-IMAC and positive fractions have been collected and concentrated in order to perform crystallization trials. Unfortunately no protein crystals have been obtained in tested condition. To elucidate the role of a mutated variant of the cleavage site “C” of Pro Domain, it was performed a mass spectrometry analysis. Secreted S1P/SKI1 mutant C was purified from culture medium of HEK293 cell line was isolated by IMAC-Co. The sample, loaded in RP-HPLC, was denatured in 6 M Guanidine-HCl. The chromatographic fractions corresponding to the major HPLC peaks were dried out in a speed-vac concentrator and directly injected in the ESI source. Mass measurements were performed with a quadrupole-TOF spectrometer. Analysis of mass spectra, compared with wild-type form of S1P, allows generating a preliminary Pro Domain auto-processing profile.
Dal 1994 il batterio Helicobacter pylori è stato classificato come organismo cancerogeneno di prima classe e la sua infezione è associata a patologie gastroduodenali. Più di metà della popolazione mondiale ne è infettata con una maggiore prevalenza nei paesi sviluppati. Nonostante la maggior parte dei casi le infezioni sono asintomatiche, il 20% sviluppa gravi patologie come ulcere peptiche e nell’1% dei casi genera linfomi e gastro carcinomi. L’incidenza e le caratteristiche di questo batterio hanno ispirato batteriologi, gastroenterologi, oncologi e farmacologi per indagare gli aspetti fisiopatologici legati all’infezione, così come microbiologi, ecologi, biologi molecolari hanno cercato i fattori di virulenza coinvolti in nell’infezione. H. pylori è un batterio microaerofilico Gram negativo che colonizza la mucosa gastrica. Non è un batterio acidofilo, anche se è in grado di sopravvivere nel lume dello stomaco per un breve periodo necessario per raggiungere le cellule epiteliali spostandosi attraverso la mucosa gastrica. La colonizzazione è mediata da fattori di virulenza predominanti come la motilità flagellare associata alla chemiotassi. Per evitare che sia espulso dal tratto intestinale dalla peristalsi, il batterio H. pylori stabilisce un’infezione cronica. L’ureasi, che è un enzima nickel dipendente, che idrolizza l’urea presente in ammoniaca e CO2 tamponando il pH acido dello stomaco. I casi più gravi sono associati ai ceppi che esprimono l’isola di patogenicità cag-PAI, che consiste in un cromosoma delimitato da elementi trasponibili. Un altro importante fattore di virulenza è la tossina vacuolizzante VacA, che induce la formazione di vacuoli citoplasmatici. Anche il meccanismo di acquisizione di ferro e nickel è fondamentale per la colonizzazione batterica e dunque finemente regolata da un gran numero di geni. Lo sviluppo di un vaccino e nuovi antibiotici nutrono una costante ricerca di nuovi possibili bersagli farmacologici, necessari per completa ed efficiente eradicazione del batterio H. pylori. In questa tesi sono stati analizzati il ruolo e la struttura di alcune proteine patogenetiche del H. pylori. Questi potenziali target farmacologici sono stati clonati, otto su undici sono stati espressi in un sistema eterologo, due proteine di quelle purificate hanno generato cristalli e di una sola ne è stata definita la struttura molecolare. In particolare è stato definito un possibile ruolo della proteina CeuE (HP1561), appartenete alla famiglia delle proteine che legano un substrato, cristallizzata in presenza del complesso Ni(His)2 e definita l’affinità con lo stesso in vitro. Del flagello, che svolge un ruolo chiave durante l’infezione, ne è stata studiata la proteina coinvolta nella formazione dell’uncino FlgD che è stata clonata, espressa, purificata e cristallizzata. Inoltre è stato riportato anche uno studio di altri fattori del flagello e di alcune proteine coinvolte nella risposta allo stress cellulare. Per ottenere tali risultati sono stati utilizzati approcci differenti. Per individuare le migliori proteine candidate per uno studio cristallografico e progettare costrutti funzionali sono state effettuate predizioni bioinformatiche. Gli amplificati di PCR sono stati clonati in vettori plasmidici. Le condizioni di espressione sono state ottimizzate e fatte in E. coli, un sistema di espressione eterologo. La solubilità delle proteine ricombinanti è stata analizzata e ottenuta anche mediante refolding. Sono stati usati diversi sistemi di purificazione per ottenere un buon grado di purezza. Per la caratterizzazione proteica sono state usate come tecniche la gel filtrazione analitica, spettroscopia UV, DLS (Dynamic Light Scattering) e dicroismo circolare. Le proteine sono state concentrate e sottoposte a esperimenti di cristallizzazione. I cristalli sono stati analizzati al sincrotrone ESRF (Grenoble, France). Spettroscopia di fluorescenza, SPR (surface plasmon resonance) e spettroscopia di massa sono le tecniche utilizzate per la caratterizzazione In Vitro. Nel secondo capitolo viene decritta la struttura tridimensionale di una proteina patogenetica di H. pylori, cristallizzata in presenza del suo possibile substrato fisiologico. HP1561 (CeuE) è una proteina di H. pylori annotata come componente periplasmatico di un trasportatore ABC che lega e trasporta il ferro. Recentemente è stato pubblicato chele ceuE e fecDE di H. mustelae codificano per proteine coinvolte nel acquisizione del nickel e cobalto. Nei Gram negativi, l’acquisizione del nickel è garantita da sistemi di proteine che operano a livello di membrana e periplasmatico. Per l’acquisizione del nickel, l’ H. pylori integra diversi sistemi non ancora caratterizzati, necessari per la maturazione di enzimi chiave come l’ureasi e l’idrogenasi. Per chiarire tale contraddizione nel sistema di acquisizione del nickel nell’H. pylori, CeuE è stata clonata, espressa, purificata, cristallizzata e la sua struttura è stata risolta. L’identità di sequenza tra i due Helicobacter (pylori e mustelae) è del 44%. Le due Istidine (H103 e H197), potenzialmente coinvolte nel legame di coordinazione del sistema sideroforo/Ni2+ nel H. pylori CeuE, risultano essere parzialmente conservate. L’His corrispondente alla His103 di H. pylori è conservata, mentre His197 è sostituita da una Leucina. Al fine d’identificare se tale mutazione possa influenzare il legame sideroforo/Ni2+, è stato prodotto e purificato il mutante H. pylori CeuE H197L. La struttura molecolare di H. pylori CeuE è stata determinata con una risoluzione di 1.65 Å mediante metodo SAD, sia nella forma apo, che in complesso col Ni(His)2. Essa è costituita da due domini globulari simili, ognuno costituito da cinque foglietti-β circondati da α-eliche, comunemente classificato come Rossman fold. Strutturalmente H. pylori CeuE appartiene alla Classe III della famiglia di proteine che legano un substrato specifico (SBPs). Dati cristallografici, saggi di fluorescenza e analisi all’SPR ci permettono di escludere il coinvolgimento della proteina nel trasporto della VitB12, eme, entrobactina, e ioni Ni2+ isolati. Al contrario la struttura della proteina/complesso Ni(His)2 e le costanti di dissociazione ottenute mediante SPR suggeriscono che H. pylori CeuE lega e trasporta il nickel in vivo mediante il complesso Ni2+/His o altro ligando che lo mima. Nel terzo capitolo viene presentato lo studio su FlgD, una proteina flagellare fondamentale nella formazione di un complesso extracellulare, l’uncino del flagello. La motilità dell’H. pylori è considerata un fattore di colonizzazione, attraverso il quale ceppi meno motili hanno minori possibilità di colonizzare e sopravvivere nell’ospite di ceppi più motili. Per la formazione del flagello sono coinvolti più di 50 geni per la regolazione e l’assemblaggio delle varie componenti. Le tre componenti principali sono il filamento, l’uncino e il corpo basale. FlgD non è presente quando il flagello è maturo, ma ha un ruolo chiave durante l’assemblaggio. Perciò, è stato classificato come proteina necessaria per l’impalcatura dell’uncino (hook scaffolding protein), considerata anche proteina di testa dell’uncino (capping protein) in quanto interagisce con FlgL, FlgK e le proteine del corpo basale. Nel ceppo H. pylori G27, FlgD corrisponde al gene hp0858 che è stato amplificato dal DNA genomico purificato e clonato in un vettore plasmidico. La proteina è stata prodotta in E. coli BL21 e la proteina è risultata essere solubile. Gel filtrazione analitica e misure al DLS confermano il suo stato di oligomerizzazione, che risulta essere un tetramero in soluzione. La proteina è stata concentrata fino a 30 g/l e cristallizzata dopo un paio di mesi d’incubazione. I cristalli hanno diffratto a una risoluzione massima di 2.7 Å. Per la sostituzione molecolare è stata usata la tecnica del homology modelling. Sono stati costruiti diversi modelli molecolari per fittare i dati sperimentali. La struttura secondaria dei modelli generati è stata comparata con gli spettri di dicroismo circolare, dove FlgD è risultata essere composta da un 12% di eliche e complessivamente da un 45% di foglietti beta (190-260nm). Le statistiche cristallografiche non hanno dato convergenza positiva negli esperimenti di sostituzione molecolare con i modelli testati. Per risolvere la struttura di FlgD sono necessari cristalli di FlgD derivatizzata con Selenometionine, che è stata espressa, purificata e cristallizzata. Nel quarto capitolo sono riportate le proteine patogenetiche di H. pylori che sono state caratterizzate in questa tesi. Queste proteine possono essere divise in due gruppi, il primo delle proteine flagellarli ed il secondo delle proteine coinvolte nella risposta allo stress cellulare in collaborazione con il Prof. V. Scarlato del dipartimento di Biologia dell’università di Bologna. FliN è una proteina citosolica localizzata nell’anello C del corpo basale del flagello ed interagisce con altri due componenti FliM e FliG. Mutazioni missenso di fliN sono state associate a ceppi non-motili ed è stato riportato che regola la rotazione oraria/antioraria del flagello. H. pylori FliN è stata clonata, espresso e purificata dai corpi d’inclusione dopo refolding. Lo grado di oligomerizzazione è stato analizzato mediante DLS e gel filtrazione analitica. La proteina è risultata essere polidispersa i soluzione e non sono stati ottenuti cristalli di proteina. FliD è la proteina “capping” del filamento cellulare ed è stato osservato che interagisce con FliT, che non è solo un chaperon substrato specifico del sistema III di esporto flagellare, ma inibisce anche l’espressione di fliD attraverso l’interazione con il complesso FlhD4C2. Al fine di analizzare la struttura del complesso FliD-FliT, è stata pianificata la co-espressione di queste proteine. Entrambe sono state clonate con un sistema di purificazione differente, ma solo la purificazione di FliT è stata possibile dai corpi d’inclusione. Lo spettro di dicroismo circolare ha rivelato una forte componente di foglietti-β nella struttura secondaria. Secondo le misure di DLS e gel filtrazione analitica FliT è polidispersa in soluzione e perciò non stati ottenuti cristalli della stessa. FlgN è una proteina del sistema secrezione tipo III ed è stato osservato che interagisce in maniera specifica con le proteine di giunzione dell’uncino con il filamento FlgK ed FlgL, prevenendone la proteolizzazione prima della maturazione del flagello. Queste proteine sono state clonate in differenti tipi di vettori plasmidici, ma solo FlgN è stata efficacemente espressa in E. coli. FlgN ricombinante è stata purificata mediante Ni-IMAC è risultata essere solubile. La proteina è stata caratterizzata con gel filtrazione analitica, DLS e CD. La proteina è un monomero in soluzione con un 30% di struttura secondaria non definita (190-260 nm). FlgN è stata concentrata e sottoposta a test di cristallizzazione. Nell’ultimo gruppo ci sono tre proteine HSPs (Heat Shock Response), prodotte dal batterio quando incontra stress come elevate temperature, etanolo, H2O2 e acidi. E’ stato accurato che le HSPs di H. pylori svolgono un ruolo importante durante l’infezione dell’ospite. HrcA e HspR reprimono la trascrizione di groESL e dnaK. L’attività di HrcA è influenzata dalla presenza di HspR, in quanto è stato dimostrato che HrcA non è in grado di legare il DNA in assenza di HspR. Queste due proteine sono state espresse in E. coli e purificate con Ni-IMAC. Durante le fasi di concentrazione hanno mostrato un limite di solubilità. Mutagenesi mirata sul costrutto di HspR e screening di detergenti su HrcA sono hanno migliorato il sistema, senza però riuscire ad ottenere una condizione ottimale per la formazione di cristalli di proteina. HP1026 (ORF) è un gene presente nello stesso operone di HspR (hp1025), ma con funzione non nota. Dall’analisi della sequenza è stato identificato un dominio con attività elicasica ed un dominio legante l’ATP. La proteina è stata espressa in E. coli e purificata con Ni-IMAC. Per la caratterizzazione sono state effettuate gel filtrazione analitica e dicroismo circolare. La proteina risulta essere un dimero in soluzione con un 35% di α-elica. I test di cristallizzazione son stati effettuati scrinando diverse concentrazioni e anche in presenza del possibile cofattore, ATPγS in forma non idrolizzabile. Nessun cristallo è stato ottenuto dalle condizioni testate. Appendice: Studio strutturale e funzionale della proteasi umana S1P/SKI1 Lo studio di questa proteasi umana è stato effettuato in collaborazione con il Prof. S. Kunz dell’Istituto di Microbiologia, del Centro Universitario Ospedaliero e dall’ Univ. Di Lausanne, Svizzera. S1P/SKI1 è una serina proteasi della famiglia delle Proprotein Convertasi (PCs). Lo scopo di membri di questa famiglia è quello di mediare l’attivazione di diversi importanti substrati per la vita cellulare. Tra queste proteasi, S1P presenta una specificità di substrato, con un sito di taglio dopo un residuo non basico. Tra i target cellulari di S1P sono stati identificati SREBP-2, coinvolto nella biosintesi dei lipidi e del colesterolo, BDNF, ATF-6 e glicoproteine superficiali di virus appartenenti alla famiglia delle Arenaviridae. S1P pesa 118kDa ed è una proteina multidominio; quindi 2 regioni di S1P sono state studiate, il “Prodomain” (ProD) che regola l’attività catalitica, ed il “cathalytic domain” (cS1P) che include i residui responsabili per la reazione proteasica. Inoltre è stato analizzato un mutante inattivo (cS1P_H249A) e due costrutti per il dominio di regolazione (ProD_AB e ProD_AC). Le sequenze nucleotidiche dei corrispettivi costrutti sono state sintetizzate come geni ottimizzati per l’espressione in E. coli e subclonati in vettori plasmidici per l’espressione ottenendo proteine in fusione con una coda di 6-His. Questi costrutti sono stati espressi in E. coli, purificati con Ni-IMAC e le frazioni positive sono state raccolte e concentrate per test di cristallizzazione. Sfortunatamente non sono stati ottenuti cristalli di proteina nelle condizioni testate. Per chiarire il ruolo di una variante mutata nel sito di taglio “C” del dominio di regolazione è stata effettuata una analisi di spettrometria di massa. La proteina secreta S1P mut C (sS1P_MutC, 116kDa) è stata purificata dal medium di coltura di una linea di HEK293 trasfettate e isolata con Co-IMAC. Il campione è stato denaturato in Guanidinio 6M e caricato in HPLC. Le frazioni corrispondenti ai picchi predominanti sono stati essiccati ed iniettati in spettrometro di massa (ESI-TOF). L’analisi delle masse, confrontate con la forma nativa (sS1P_WT) ha permesso di generare un profilo preliminare del pattern di processamento del dominio di regolazione (ProD) with a quadrupole-TOF spectrometer. Analysis of mass spectra, compared with wild-type form of S1P, allows generating a Pro Domain auto-processing profile.

Introdução: O Helicobacter pylori adquiriu grande importância durante as últimas décadas, ao ser reconhecido como um importante patogénio que infeta uma grande parte da população humana. Esta bactéria, localizada na mucosa gástrica, apresenta uma relação causal com algumas patologias, tais como: carcinoma gástrico, úlcera péptica, entre outras. A sua erradicação representa um grande desafio para os clínicos. O aumento gradual da falha do tratamento obriga a utilizar novos esquemas terapêuticos e a procurar novas soluções. As taxas de eficácia de erradicação do Helicobacter pylori têm vindo a diminuir, pois a resistência aos antibióticos, nomeadamente à claritromicina, está a aumentar, tornando-se assim no principal fator para a falência do tratamento. A presente dissertação pretende efetuar uma revisão sistemática com base em publicações científicas relacionadas com a eficácia da terapêutica de erradicação do Helicobacter pylori. Métodos: Foram pesquisadas publicações indexadas nas bases de dados Pubmed, Elsevier, Wiley e B-On, na biblioteca eletrónica da Faculdade de Ciências da Saúde da Universidade da Beira Interior. Utilizaram-se os seguintes termos no título: efficacy, therapeutic ou therapy, helicobacter pylori, durante o período compreendido entre 01/01/2012 e 26/03/2013. Foram selecionados dez publicações para análise. Resultados: Dos dez estudos selecionados foram encontrados esquemas de primeira, segunda e terceira linha, onde os regimes utlizados foram terapia tripla, quádrupla sequencial, sequencial modificada e concomitante, variando a duração de tratamento entre os 5, 7, 10 e 14 dias. Na primeira linha de tratamento o esquema que apresentou mais eficácia com 96,5% utilizou uma terapia quádrupla concomitante, na segunda linda 93,6% com uma terapia tripla e por fim, na terceira linha 89,5% também com uma terapia tripla. Devido à heterogeneidade dos esquemas apresentados nas publicações não foi possível nenhuma análise estatística. Alguns estudos documentaram a resistência aos antibióticos, que variou entre os 23,4% a 78,7% ao metronidazole e entre 0% a 91,7% à claritromicina. Os efeitos adversos major variaram de 0,5% a 4,6% enquanto os minor variaram de 21,8% até 80%. Conclusão: Na primeira linha de tratamento, a terapia tripla de sete dias deve ser repensada e as terapias sequencial e concomitante são eficazes. Em relação à terapêutica de segunda linha, deve-se utilizar uma quinolona e terapia concomitante, se esta não foi utilizada na primeira linha, ou então uma terapia tripla de 14 dias. A terapia de terceira linha não necessita obrigatoriamente de ser orientada pelo teste de sensibilidade antibiótica para erradicar a bactéria. Diversos fatores influenciam a eficácia do tratamento, nomeadamente a resistência aos agentes antimicrobianos e a adesão do paciente à terapêutica.

Велика ли роль инфекции Helicobacter pylori на патогенез неалкогольной жировой болезни печени (НАЖБП)? Последние данные свидетельствуют о наличии их взаимосвязи [1, 2]. Однако до сих пор данная тема остается под вопросом. Цель данной работы - исследовать возможную связь и клиническое значение Helicobacter pylori в патогенезе неалкогольной жировой болезни печени. Is the role of Helicobacter pylori infection on the pathogenesis of non-alcoholic fatty liver disease (NAFLD) significant? Recent data indicate the presence of their relationship [1, 2]. However, until now, this topic remains in question. The aim of this work is to investigate the possible relationship and clinical significance of Helicobacter pylori in the pathogenesis of non-alcoholic fatty liver disease

The resistance of Helicobacter pylori to clarithromycin was studied and compared with the frequency of antibiotic use for other reasons in patients with gastroesophageal reflux disease. The resistance of Helicobacter pylori to clarithromycin in patients with gastroesophageal reflux disease was determined by detecting specific DNA loci T2182C, A2142G/C and A2143G and amounted to 24%. According to medical histories and outpatient patient records, clarithromycin was used in the examined patients in 25% of cases, which is comparable to the frequency of Helicobacter pylori resistance detected by the molecular method. Routine monitoring of the use of antibiotics in real clinical practice in patients of a certain service region, in the absence of the possibility of using other techniques, may be a surrogate way to predict the development of Helicobacter pylori resistance.

Одними из ключевых промоторов в регуляции каскада воспалительных медиаторов являются тучные клетки, обладающие широким арсеналом биологически активных веществ. В патогенезе гастрита, ассоциированного с H. pylori принимают активное участие различные виды иммунокомпетентных клеток - макрофаги, нейтрофилы, эозинофилы, дендритные клетки, Т- и В-лимфоциты, а также тучные клетки. Антигенпредставляющие свойства тучных клеток представляют интерес в аспекте взаимодействия с Helicobacter pylori (H. Pylori)

Introdução: A gastrite crônica é principalmente causada pelo hipercloridrismo no piloro por infecção pelo Helicobacter pylori. Essa bactéria é um bacilo flagelado espiralado que se localiza sobre o epitélio da área antro-piloro. Nessa região, altera a fisiologia local e inibe o feedback negativo, inativando as células D e induzindo a hipercloridria. A virulência do H. pilory é baseada em 4 fundamentos: Flagelos: mobilidade no muco; Urease: eleva o pH gástrico; Adesinas: aderência às células foveolares (glândulas gástricas) – presente na biópsia e fator determinante para o diagnóstico e Toxinas: CagA (úlcera e câncer associado – metaplasia intestinal). Objetivos: O presente estudo visa verificar os fatores associados com o diagnóstico de gastrite crônica e a presença do H. pylori e demonstrar a importância da prevenção e tratamento da doença. Material e métodos: Este trabalho trata-se de uma revisão bibliográfica, que visa demonstração de características sobre manifestação clínica da gastrite associada ao H. pylori baseada em estudos passados. Para a realização do estudo, foram utilizados livros e artigos encontrados em sites acadêmicos como Google acadêmico e Scielo. Resultado: O Helicobacter pylori causa gastrite ao estimular a produção de citocinas pró-inflamatórias e destruir diretamente as células epiteliais. A gastrite é dividida em duas categorias, aguda e crônica, ambas com diferentes graus de descamação da superfície epitelial gástrica e diferentes graus de infiltração inflamatória. Na fase aguda, pode haver casos leves sem grandes alterações inflamatórias, enquanto em casos mais graves a inflamação pode ter sangramento adicional ou mesmo erosões da mucosa. A inflamação crônica da mucosa causada pelo Helicobacter pylori reduz a secreção ácida, levando à hipoacidez, além de reduzir a secreção de pepsina, contribuindo na proliferação bacteriana e na persistência da doença, aumentando o risco de mutações genômicas. Conclusão: A gastrite é uma patologia caracterizada por alterações histológicas na mucosa gástrica, na qual se observa infiltração de células inflamatórias. É a lesão mais comum que acomete o estômago. Pode-se concluir que múltiplas etiologias interagem para o aparecimento da gastrite crônica. Em palavras derradeiras, deve-se manter uma nutrição adequada ao longo da vida como método profilático contra o aparecimento de gastrite e o Helicobacter pylori.

Introdução: A Helicobacter pylori é uma bactéria gram-negativa encontrada na mucosa gástrica, está associada a várias patologias relacionadas ao trato gastrointestinal, como gastrite crônica, úlcera péptica, linfoma MALT, adenocarcinoma gástrico. Estima-se que a prevalência seja de aproximadamente 50% na população mundial. Na mucosa gástrica a presença da Helicobacter pylori provoca a resposta pro-inflamatória, associada a lesão celular, como a lesão do material genético e produção de espécies reativas de oxigênio, podendo gerar mutações. Essa bactéria pode modificar muitos processos biológicos, influenciando na ocorrência de doenças extra-digestivas. Objetivo: Relatar um caso de trombocitopenia induzida pela Helicobacter pylori. Descrição do caso: Paciente do sexo feminino, 45 anos, natural e residente de Campos dos Goytacazes/RJ, comparece a consulta com relato de que há aproximadamente 2 meses, realizou exames de rotina com o ginecologista, que a encaminhou ao hematologista, devido a alteração na contagem de plaquetas (trombocitopenia). Nega febre, emagrecimento, sudorese noturna, sangramentos. Nega também sintomas gripais nos últimos meses. Ao exame físico: bom estado geral, lúcida, orientada, normocorada, hidratada, acianótica e anicté- rica; apresenta petéquias no tronco e nos membros inferiores; RCR 2T, sem sopro, FC 78 bpm, PA 110/80mmHg; MVUA sem RA, FR 12 irpm; abdômen flácido, depressível, peristalse presente, indolor a palpação superficial e profunda, sem visceromegalias palpáveis e espaço de Traube timpânico; MMII sem edema, panturrilhas livres e pulsos pediosos palpáveis. Foi solicitado exames laboratoriais e ultrassonografia de abdômen total. Laboratório: hemoglobina 12,6; hematócrito 38,70; VCM 83; HCM 27; leucócitos 6900; plaquetas 26.000; MPV 10,2; creatinina 0,79; ureia 42; sódio 134; potássio 4,1; cálcio sérico 9,3; bt 0,43; Bd 0,16; Bi 0,27; TGO 23; TGP 18; LDH 137. A USG de abdômen total demonstrou: fígado com dimensões levemente aumentadas, com predomínio do lobo direito, contornos regulares, parênquima homogênea. Veia porta com calibre normal. Vias biliares intra e extra-hepáticas sem dilatações evidentes. Colédoco com calibre normal. Vesícula biliar com dimensões normais, paredes finas, sem cálculos em seu interior. Pâncreas com aspecto anatômico. Baço com dimensões conservadas, contornos regulares e ecotextura homogênea. Rins de volume, contornos e ecogenicidade normais, não há dilatação dos sistemas coletores. Durante a consulta a paciente relatou que fazia uso de anticoncepcional oral combinado e omeprazol, devido a pirose. Desta forma, com os exames laboratoriais e USG de abdômen total sem alterações que demonstrassem a causa da trombocitopenia, foi solicitado uma endoscopia digestiva alta, devido a queixa de pirose. A EDA apresentou o teste da urease positivo demonstrando a infecção por Helicobacter pylori. A paciente foi orientada em relação ao tratamento contra a Helicobacter pylori. Após o tratamento foi solicitado um novo exame laboratorial, que demonstrou a contagem normal de plaquetas. Conclusão: O Helicobacter pylori é um patógeno de grande prevalência e repercussão, local e sistêmica. Este relato coloca em elucidação o impacto hematológico causado pela bactéria H.pylori, incitando o seu efeito causal nas trombocitopenias, devendo sempre estar em suspeição durante o processo diagnóstico.

Review question / Objective: Is gastric helicobacter pylori infection related to periodontal diseases? Condition being studied: Therefore, the aim of this systematic review and meta-analysis was to identify and analyze clinical studies to determine the direct correlation between Helicobacter Pylori gastric infection andPeriodontal Disease. Study designs to be included: Clinical studies that provided data on Helicobacter Pylori infection in both the stomach and oral cavity, confirmed by polymerase chain reaction (PCR), rapid urease test (RUT) or enzyme-linked immunosorbent assay (ELISA). Clinical studies that associated PD with Helicobacter Pylori. The diagnosis of PD was confirmed ac-cording to the diagnostic criteria in periodontology.