Tesis sobre el tema "Hyperbaric oxygenation"

This study investigated the effects of hyperbaric oxygen (HBO2) therapy following partial arthroscopic meniscectomy surgery on swelling, perceived pain, range of motion at the knee joint, isokinetic strength, and leg function. Subjects were 8 males and 1 female with an acute tear to the meniscus. Subjects were randomly assigned to either a control group (n = 5) or an HBO2 treatment group (n = 5). The HBO 2 group received 5 HBO2 treatments at 2.5 ATA for 90 minutes at 95% O2 beginning 24 hours post-operation. Both groups were tested pre-operation (day 0) and on days 1, 2, 3, 4, 5, 20, 35, and 50 post-surgery. No significant difference was found between groups for any of the dependant variables. The results indicated that the control and HBO2 groups responded in a similar pattern when assessed for swelling, perceived pain, range of motion at the knee joint, leg function and isokinetic strength.

At present, the Eastern Cape is the only province in South Africa lacking a clinical hospital-based hyperbaric facility. East Cape Hyperbaric, to be situated at Greenacres Hospital in the Nelson Mandela Metropolitan, will offer the Eastern Cape community access to a world-class facility that will offer their patients Hyperbaric Oxygen Therapy and a Wound-Healing Facility. The objective of this study was to assess the viability of establishing a Hyperbaric Oxygen Therapy (HBOT) facility for the Nelson Mandela Metropolitan Municipality (NMMM), using sound business planning principles. A business plan precisely defines the business, identifies the goals, and serves as the firm's resume. A business plan will assist in allocating resources effectively, handle unforeseen complications, and assist in making sound business decisions. Because it provides specific and organized information about the company and how the company will repay borrowed money, a good business plan is a crucial part of business planning. In order to quantify the demand for a Hyperbaric Oxygen Therapy facility, a questionnaire was designed, in such a manner as to identify the current demand for a HBOT facility. The questionnaires were distributed to all medical practitioners within the NMMM by means of fax, e-mail and hand-delivery. Research conducted indicates that the results are promising enough to warrant the expedient creation of this business facility.

Introduction: Hyperbaric oxygen therapy (HBOT) is the administration of 100% oxygen at pressures greater than 1 atmosphere. One recurrent criticism that has been made of this field is that treatment is based on little or no good clinical evidence. Aims: The primary objective of this thesis is to make a useful response to that criticism. I planned to collate all the available randomised evidence in the fields of diving and hyperbaric medicine, supply a critical appraisal of each paper, and synthesise that evidence in a series of systematic reviews with meta-analysis. I also intended to use a cost analysis of hyperbaric practice in our own facility to inform formal cost-effectiveness analysis using the estimates of effect generated by the individual meta-analyses. Methods: A comprehensive search strategy was used to identify all clinical RCTs involving the administration of hyperbaric breathing mixtures. Each trial was appraised using the software developed by the Oxford Centre for Evidence Based Medicine. Each critical appraisal was loaded onto a searchable web site at www.hboevidence.com. Each diagnostic category identified was considered for inclusion in a Cochrane systematic review and meta-analysis. Results: The database includes 130 critical appraisals covering 173 separate reports. The site has received more than 17,000 hits. There are 12 formal meta-analytical reviews and all have been accepted for publication in the Cochrane Database of Systematic Reviews at the time of writing. These form the basis of this thesis and include late radiation tissue injury, chronic wounds, acute hearing loss and tinnitus, multiple sclerosis and decompression illness. The meta-analyses in this thesis suggest there are several areas where HBOT is associated with improved clinical outcomes and that routine use is probably justified in some areas (e.g. radiation proctitis healing with HBOT: NNT 3, 95%CI 2 to 11). On the other hand, these analyses suggest there is most unlikely to be significant clinical benefit from the application of HBOT to patients currently referred for HBOT (e.g. multiple sclerosis). Conclusions: The randomised evidence for the use of HBOT is now significantly easier to access. Recommendations for therapy and future research directions can be made on the basis of these analyses.

The purpose of this study was to examine the effects of HBO2 therapy on exercise-induced muscle damage. Subjects (n = 16 university student volunteers) were randomly divided into an experimental group that received HBO2 therapy and a control group that did not receive any treatments. HBO2 treatments consisted of 5 sessions of breathing 95% oxygen at 2.5 atm abs for 100 min. Temporary muscle soreness was created using a single-leg eccentric exercise task involving the quadriceps femoris. Over the next 14 days, measurements were obtained on muscle soreness, leg circumference, quadriceps peak torque, quadriceps average power, fatigue and plasma creative kinase. After eccentric exercise, plasma CK levels and perceived muscle soreness were elevated but were not different between HBO2 and control groups. HBO2 therapy did not alter leg circumference, quadriceps peak torque, average power or fatigue compared to the control group. The data indicated that five HBO2 treatments did not speed recovery following eccentric exercise that induced temporary muscle damage.

Despite lack of scientific evidence, hyperbaric oxygen therapy (HBO2) has been used as a treatment for children with cerebral palsy (CP). Recently, a multi-centre randomised, double-blind, placebo-controlled trial assessed the efficacy of HBO2 therapy for children with CP. Using the same cohort, the purpose of this study was to examine the effectiveness of HBO2 therapy on hand function using the Jebsen-Taylor test. All children received 40 treatments over a 2-month period. HBO2 treatments were 60 minutes with 100% O2 at 1.75 atmospheres absolute (ATA). Placebo treatments were also 60 minutes with air (21% O2) at 1.3 ATA. Seventy-eight children with CP, aged 3--12 years completed pre and post hand function assessments. Hand function was evaluated using one quantitative measure (time) and three qualitative measures. There were no significant changes between baseline and follow-up tests for any of the measures, although both experimental and control groups improved ( p = 0.08) their total times for the Jebsen test. The HBO2 group improved by 54.5 seconds (8.8%) while the placebo group improved by 47.8 seconds (7.7%). The results indicate that HBO2 therapy did not enhance the hand function of children with CP.

Purpose. The purpose was to examine venous PO2, transcutaneous tissue PO2 (PtcO 2), and VO2max in a normobaric environment following a single HBO2 treatment. Methods. Ten moderately trained (VO2max = 57.6 mL·kg-1·min -1) males volunteered for the study. Baseline testing included measures of VO2max, PtcO2, and anthropometry. Subjects received two HBO2 treatments, which consisted of breathing 95% oxygen at 2.5 ATA for 90 min. Following the first HBO2 treatment (6.0 +/- 1.0 min), subjects performed a VO2max test. Following the second HBO2 treatment, leg and chest PtcO2 and venous PO2 were monitored for 60 min. Results . VO2max, running time, and peak La were not altered (p < 0.05) post-HBO2 treatment. Leg PtcO2 was lower (p < 0.05) and chest PtcO2 was unchanged following the HBO2 treatment compared to baseline values. Venous PO2 was lower in the first 3 min post-HBO2 treatment than subsequent values, but no other differences were found (p < 0.05). Conclusion. The results of this study show that a single HBO 2 treatment at 2.5 ATA for 90 min does not elevate venous PO2, PtcO2, or VO2max in a normobaric, normoxic environment.

This study investigated the effects of hyperbaric oxygen (HBO) therapy on acute ankle injuries and determined if HBO therapy shortened time to recovery, decreased edema and pain, and increased range of motion and strength of the ankle. Subjects were randomly assigned to either an experimental (HBO) group (n = 4) or a control group (n = 4). All subjects received the same standardized physical therapy for lateral ankle sprains at the McGill Sport Medicine Clinic. The HBO group received 5 consecutive HBO treatments at 2.5 ATA for 90 minutes starting within 24 hours post injury. The control group received no HBO treatments. All subjects were evaluated by a physician within 24 hours of injury. All subjects suffered a second-degree lateral ankle sprain. Pain, range of motion, strength, volume displacement, and function were evaluated on the day of injury (Day 1), on Day 6 post injury, and on the day of return to play (Day RTP). There was no significant difference in time to return to play. However, the HBO group (25.5 +/- 11.6 days) did return 31% faster than the control group (36.8 +/- 19.4 days). There were no differences found between groups on the variables. There was a decrease in pain found over time (Day 1 was 57 mm, Day 6 was 18.5 mm, and Day RTP was 7 mm). The results of this study suggest that with treatment of HBO there is no effect on ankle sprains for return to play or improved function.

[Truncated abstract] Therapeutic Radiation has been used for the treatment of cancer and other diseases for nearly a century. Over the past 20 years, Hyperbaric Oxygen Treatment (HBOT) has been used to assist wound healing in the prevention and treatment of the more severe complications associated with the side effects of Therapeutic Radiation Treatment (TRT). The use of HBOT is based on the premise that increased oxygen tissue tension aids wound healing by increasing the hypoxic gradient and stimulating angiogenesis and fibroblast differentiation. As it takes up to 6 months for a hypoxic state to develop in treated tissue, following radiation treatment, current recommendations for HBOT state that it is not effective until after this time. During this 6 month period, immediately following TRT, many specialized tissues in or adjacent to the field of irradiation, such as salivary glands and bone, are damaged due to a progressive thickening of arteries and fibrosis, and these tissues are never replaced. Currently, HBOT is used to treat the complications of TRT, but it would be far better if they could be prevented . . . In summary, this experimental model has fulfilled its prime objective of demonstrating that HBOT is effective in reducing the long-term side effects of therapeutic radiation treatment in normal tissue, when given one week after the completion of the radiation treatment and statistically disproves the Null Hypothesis that there is no difference in the incidence of postoperative complications or morbidity of TRT when 20 intermittent daily HBOT are started one week after completion of TRT. This project provides an extensive description of the histological process and also proposes a hypothesis for the molecular events that may be taking place.

Hyperbaric Oxygenation Therapy (HBOT) has a successive history for treating very specific groups of physical conditions. Research by Neubauer and colleagues states that HBOT's ability to increase cerebral metabolism in the brain regenerates dormant neural tissue (Neubauer, Gottlieb, & Pevsner 1994). According to this research, the increase of cerebral metabolism levels restores mental capacity from the neurological insult. Despite promise, uncertainty exists as to whether this is a viable treatment option for people suffering from neural damage. The research results for this experiment will examine the effect of HBOT on cerebral metabolism levels in adults and pediatrics with chronic neurological problems. Fifty individuals diagnosed as having a neurological impairment whom met criteria for the study were analyzed from an archival data set. Criterion required chronic impairment, baseline SPECT, followed by HBOT exposures, and a post SPECT scan. Statistical analyses consisted of a Pearson correlation that examined pre-metabolism rates with total change, a Pearson correlation that examined total change and number of treatments, and a one way ANOVA analysis that examined cerebral metabolism change in patients under 18 and over 18. Results indicated change

Thesis Ph. D.)(Chemical Engineering)--University of Pretoria, 2003.
Title from opening screen (viewed Oct. 06, 2004). Summaries in English and Afrikaans. Includes bibliographical references (leaves 144-151).

Procurou-se confirmar a existência de alterações estruturais em corpos carotídeos de ratos expostos à hiperóxia que pudessem explicar a atenuação da resposta fisiológica à hipóxia nessas condições descrita na literatura. Também testamos a hipótese de haver um desvio de fluxo sanguíneo para os capilares intraglômicos em situações de hiperoxigenação hiperbárica.15 ratos machos Wistar adultos foram divididos em 3 grupos e expostos a 2,4 ATA por 6 horas, a 3,0 ATA por 6 horas e a ar ambiente (grupo controle). Os resultados obtidos através de análise histológica e morfométrica mostraram: a) nenhuma alteração da arquitetura dos corpos carotídeos, mas as células expostas à dose mais elevada apresentaram-se com citoplasma desarranjado, confirmado pela microscopia eletrônica; b) um aumento significativo da densidade volumétrica de capilares preenchidos por hemácias, mas não do estroma intersticial, no grupo exposto à dose mais elevada de O2 c) uma vasoconstricção significativa das arteríolas maiores em todas as doses de oxigênio empregadas no estudo e das arteríolas menores na dose mais elevada de O2; d) variações significativas na proporção das variantes de células glômicas no grupo exposto a menor dose de O2; e) mitocôndrias com poucas cristas, tanto nas células glômicas quanto nas terminações nervosas, embora nas primeiras apresentem-se bem deformadas; f) proliferação membranosa citoplasmática com aumento de REG e Golgi nas células glômicas e sustentaculares. Esses resultados sugerem um desvio do fluxo dos vasos mais calibrosos em direção aos capilares intraglômicos, confirmando nossa hipótese inicial e indicam que o oxigênio, dependendo da dose utilizada, exerce um efeito tóxico importante sobre os corpos carotídeos, com alterações significativas da ultraestrutura das células glômicas e terminações nervosas.
We sough to confirm the existence of structural alterations in rat carotid bodies exposed to hyperoxia that could explain the attenuation of the ventilatory hypoxic drive (HD) by hyperoxic conditions described in the literature. We also tested the hypothesis of there being a deviation of blood flow toward intraglomic capillaries in situations of hyperbaric oxygenation (HBO).15 adult male Wistar rats were divided in 3 groups and exposed to O2 at 2.4 ATA for 6 hours, at 3.0 ATA for 6 hours and to air at 1.0 ATA (control group). The results obtained through histological and morphometric analysis showed: a) no alteration in the architecture of the carotid bodies, but the cytoplasm of the cells exposed to the highest dose were disarranged, a feature confirmed by electron microscopy; b) a significant increase in volume density of capillaries filled out by red blood cells but not of interstitial stroma in the group exposed to O2 at the highest dose; c) a significant vasoconstriction of larger arterioles in all doses of oxygen employed in the study and of smaller arterioles at the highest dose of O2; d) significant variations in the proportion of glomic cell variants in the group exposed to the lowest dose of O2; e) mitochondria with few cristae, so in glomic cells as in nerve-endings, although in the former they were very deformed; f) cytoplasmic membranous proliferation with an increase of endoplasmic reticulum and Golgi apparatus in glomic and sustentacular cells. These results suggest a deviation of blood flow from more calibrated vessel toward intraglomic capillaries, confirming our initial hypothesis and indicate that oxygen, depending on the dose used, exerts an important toxic effect on rat carotid body with significant alterations of glomic cell and nerve-endings ultrastructure.

O objetivo deste trabalho foi avaliar os efeitos do monossialogangliosídio (GM1), da câmara de oxigenoterapia hiperbárica e de ambos no tratamento da lesão medular experimental em ratos. Trinta e dois ratos Wistar com lesão medular foram divididos em 4 grupos: um grupo recebeu o monossialogangliosídio (GM1), um segundo foi submetido à oxigenoterapia hiperbárica, um terceiro recebeu os dois tratamentos e um quarto não recebeu tratamento (controle). Não houve diferença significativa entre os grupos na análise histológica, em todas as variáveis (necrose, hemorragia, hiperemia e degeneração cística, p>0,06). Também não houve nenhuma diferença na comparação entre os lados direito e esquerdo nos testes funcionais (p>0,06 para todos). Não foram encontradas diferenças nos testes motores, na comparação entre os grupos após 2, 7 21 e 28 dias de lesão medular. Mas, na avaliação após 14 dias, o Grupo 3, o qual recebeu a terapia combinada, mostrou um escore BBB significantemente maior que os outros grupos (p=0,015). Na avaliação de 28 dias, houve uma tendência dos Grupos 1 (GM1) e 3 (terapia combinada) apresentarem um escore BBB maior que o do Grupo 4 (controle), embora sem significância estatística (p=0,057). Concluiu-se que, quanto aos índices motores, a utilização do GM-1 tem efeito benéfico, embora sem diferença estatisticamente significante e que o efeito benéfico do GM-1 é antecipado através da utilização concomitante da oxigênio terapia hiperbárica.
The objectives were to evaluate the effect of GM1 ganglioside, hyperbaric oxygen, and both in combination, in the treatment of experimental spinal cord lesions in rats. Thirty-two Wistar rats with spinal cord lesions were divided into four groups: one group received GM1 ganglioside, one was submitted to hyperbaric oxygen therapy, the third received both treatments, and the fourth received no treatment (control). There were no significant differences between the groups in the histological analysis, for any of the variables (necrosis, hemorrhage, hyperemia, cystic degeneration, p > 0.06). Neither were there any significant differences in the comparison of left and right sides in the functional tests (p > 0.06 for all). No significant differences were found in the locomotor ratings, in the comparison of groups at 2 days, 7 days, 21 days and 28 days after the surgical procedure. However, in the evaluation on day 14, Group 3, which received the combined therapy, showed a significantly higher BBB score than the other groups (p = 0.015). In the evaluation on day 28, there was a trend to Group 1 (GM1) and 3 (combined therapy) showed a higher BBB score than the group 4 (control), but with no significance (p=0,057). In conclusion, the is a benefit in the use of GM1 ganglioside, but with no significance and the therapeutic effect of GM1 in locomotor evaluation of rats submitted to spinal cord lesion is anticipated by hyperbaric oxygen therapy.

Introdução: O conhecimento da fisiopatogênese da Doença Inflamatória Intestinal (DII) tem evoluído nas últimas décadas. No entanto, apesar das terapias terem evoluído, 2/3 dos casos ainda necessitam de drogas alternativas e terapias de suporte. A busca constante de tratamentos alternativos e modalidades mais eficazes tem gerado algumas abordagens promissoras, tais como a utilização do oxigênio hiperbárico (HBO). O uso dessa terapia cresceu rapidamente nos anos 90 mostrando bons resultados e poucos efeitos colaterais sendo, posteriormente \"esquecida\" ante a eficácia apresentada pelo uso das terapias biológicas. Objetivos: Os objetivos deste trabalho foram avaliar os efeitos do tratamento com HBO em camundongos com colite induzida quimicamente pelo ácido 2,4,6 trinitro benzeno sulfônico 2,5% (TNBS), sobre a avaliação dos animais, a análise histológica, o perfil inflamatório através das citocinas IL-4, IL-10, IL-12, IL-13, IL-17, fator de necrose tumoral alfa (TNFalfa) e Interferon y e da atividade das enzimas antioxidantes superóxido dismutase (SOD), glutationa peroxidase (GPx) e glutationa redutase (GR) em intestino de camundongos. Metodologia: Camundongos machos foram divididos em 6 grupos. No grupo 1, a colite foi induzida por TNBS 2,5% + Etanol 35%, sendo chamado de grupo TNBS; o grupo 2 também recebeu TNBS 2,5% + Etanol 35% seguido do tratamento com o HBO, sendo chamado de grupo TNBS+HBO; o grupo 3 recebeu apenas o veículo etanólico a 35%, sendo chamado de grupo ÁLCOOL; o grupo 4 também recebeu o veículo etanólico a 35% associado ao HBO, sendo chamado de grupo ÁLCOOL+HBO; o grupo 5 recebeu apenas solução salina (NaCl 0,9%), sendo chamado de grupo SALINA; e o grupo 6 recebeu a solução salina associado ao HBO, sendo chamado de grupo SALINA+HBO. Durante o tratamento os animais foram avaliados diariamente. O tratamento com HBO foi realizado por 4 dias e, ao final, as amostras da porção final do intestino foram retiradas e armazenadas para análise histológica, enzimas antioxidantes e citocinas. Resultados: A avaliação mostrou que o HBO promoveu uma melhora significativa no quadro clínico desses animais. A aplicação do ácido 2,4,6 trinitro benzeno sulfônico nos animais do grupo TNBS resultou na perda de 12,71% do peso corpóreo dos animais após 24 horas e, ao final do período experimental uma perda de peso total de 14,63%. Por outro lado, os animais que também receberam 2,4,6 trinitro benzeno sulfônico associado ao tratamento com o HBO (TNBS+HBO) tiveram uma perda de apenas 7,52% nas primeiras 24 horas, apresentando uma recuperação de 5,58% de seu peso no final do período experimental. A avaliação do quadro histológico mostrou uma melhora significativa entre o grupo TNBS+HBO quando comparado com o grupo TNBS. O tratamento com HBO aumentou a atividade das enzimas antioxidantes SOD e GPx em todos os grupos, sendo somente significativo entre os grupos TNBS vs TNBS+HBO, não sendo observado diferença da GR entre os grupos. Com relação ao perfil inflamatório foi observado que o tratamento com o HBO promoveu a diminuição das citocinas pró-inflamatórias INFy, IL-12, IL-17 e TNF? e o aumento das citocinas anti-inflamatórias IL-4 e IL-10, e não houve alteração da IL-13. Em modelo experimental, esses dados representam, o potencial efeito anti-inflamatório e o do aumento das defesas antioxidantes enzimáticas promovido pelo HBO
Introduction: The Knowledge about the physiopathogenesis of inflammatory bowel disease (IBD) has evolved over the last decades. However, although therapies have improved, 2/3 of the cases still need alternative drugs and support therapy. The constant search for alternative treatments and more effective modalities has brought to light some promising strategies, as the use of hyperbaric oxygen (HBO). The use of such therapy surged rapidly in the 90´s showing good results and few side effects being, later on, \"forgotten\" due to the efficacy shown by the use of biological therapies. Objective: This study aimed to evaluate the effects of HBO treatment in mice with chemically induced colitis, using 2,4,6 trinitrobenzene sulfonic acid 2,5% (TNBS) over the evaluation of the animals, histological analysis, inflammatory profile through cytokines IL-4, IL-10, IL-12, IL-13, IL-17, TNF- alfa and interferon y, and also the activity of the antioxidant enzymes superoxide dismutase (SOD), gluthatione peroxidase (GPx) and gluthatione reductase (GR) in intestine of mice. Methodology: Male mice were divided into 6 groups, in group 1, colitis was induced by TNBS 2,5%+ Ethanol 35%, named as TNBS, group 2 also received TNBS 2,5%+ Ethanol 35% + HBO, named as TNBS+HBO, group 3 received only Ethanol 35%, named as ALCOHOL, group 4 received Ethanol 35% associated with HBO, named as ALCOHOL+HBO, group 5 received Saline (NaCl 0,9%), named as SALINE and group 6 received Saline combined with HBO, named as SALINE+HBO. During the treatment the animals were evaluated daily. The treatment with HBO was performed for 4 days and at the end, the samples of the final portion of the bowel were removed and stored for histological, antioxidant enzymes and cytokines analysis. Results: This study has shown that the HBO promoted a significant improve on these animals clinical status. The group which received TNBS showed a 12,71% body weight loss after 24 hours, and by the end of the experimental period the average weight loss was 14,63%. On the other hand, the animals treated with HBO showed only 7,52% weight loss during the first 24 hours, having recovered the weight lost in 5,58% by the end of the experimental period. The histological evaluation of the TNBS+HBO group presented a significant improvement when compared with TNBS group. The treatment with HBO increased the activity of the antioxidant enzymes SOD and GPx in all groups, being only significant among the groups TNBS vs TNBS+HBO, difference in the activity of GR was not observed among the groups. Regarding the inflammatory profile, it was observed that the treatment with HBO promoted the decrease of pro-inflammatory cytokines INFy, IL-12, IL-17 and TNFalfa, as well as the increase of anti-inflammatory cytokines IL-4 and IL-10, while IL-13 was not affected. These data represents, in experimental model, the potential anti-inflammatory effect and the increase of the enzymatic antioxidant defenses promoted by the HBO

Analyses incidents which occured in hyperbaric medicine units, or as a consequence of hyperbaric oxygen exposure, with the aim of developing recommendations for safety improvement in hyperbaric medical practice. A review of the hyperbaric literature showed that ear barotrauma is the most frequently reported patient complication of hyperbaric treatment, with the second most frequently reported complication being oxygen toxicity. From the data, the study presents recommendations for quality improvement, research, policy and procedure development, education and equipment design modification.
Thesis (M.Clin.Sc.) -- University of Adelaide, Dept. of Clinical Nursing, 2001.

Introduction: Obesity is associated with a chronic low grade inflammatory state and the development of insulin resistance and diabetes, while hyperbaric oxygen therapy (HBOT) has demonstrated anti-inflammatory properties. But it was the observation that people with diabetes were susceptible to a fall in blood glucose levels during HBOT that led to an investigation of insulin sensitivity. Methods: Five human studies were reported in four publications. Four studies used the hyperinsulinaemic euglycaemic glucose clamp and one used a frequently sampled intravenous glucose tolerance test (FSIGT) to investigate insulin sensitivity during HBOT. Studies recruited men who were overweight or obese, with and without diabetes. Blood samples for inflammatory cytokines and adipose tissue biopsies for gene expression were taken to investigate possible mechanisms of action. Results: A total of sixty-two men were investigated by glucose clamp and nine by FSIGT. All four glucose clamp studies showed significant within-group increases in insulin sensitivity following exposure to HBOT. First, in a group of patients with (n=5) and without diabetes (n=5) referred for clinical HBOT, there was a 37% increase during the third HBOT and 41% increase during the thirtieth HBOT. Next, in a group of men who were overweight or obese, we found a 29% increase in men without diabetes (n=11) and 57% increase in those with diabetes (n=8) during the third HBOT. Further, the effect was still measurable in the first 30 minutes after exit from the hyperbaric chamber. Pre and post-HBOT testing found reductions in serum TNF-α and MCP-1 while IL-6 increased. Next, in a group of men who were overweight or obese but without diabetes (n=9), we found a significant 23% increase during the first HBOT intervention. There was a significant increase in serum IL-6 after HBOT but no change in TNF-α or MCP-1. The final glucose clamp study randomised men to either HBOT (n=13) or hyperbaric air (n=11) and found a significant between group difference with a 26% increase in insulin sensitivity during HBOT but no significant change in hyperbaric air. The FSIGT study performed the insulin sensitivity test on men who were overweight or obese and without diabetes (n=9) during the third HBOT and 24-hours later but found no changes from baseline. Conclusions: The glucose clamp technique identified an acute increase in insulin sensitivity during HBOT. The effect could be seen in those without diabetes which suggests it is a physiological response to HBOT. Further research is encouraged into this insulin-sensitising effect of HBOT as it could open new therapeutic pathways for glucose regulation. No change to insulin sensitivity was seen in hyperbaric air; although it was a very modest exposure this may be relevant to people in other hyperbaric environments such as diving. The response of serum inflammatory cytokines to HBOT was inconsistent however two studies that showed increased insulin sensitivity during HBOT together with increased serum IL-6 suggest the origin and role of IL-6 requires further investigation.
Thesis (Ph.D.) -- University of Adelaide, Adelaide Medical School, 2020

碩士
慈濟大學
生理暨解剖醫學碩士班
101
Diabetes is a chronic disease that occurs either when the pancreas does not produce enough insulin or when the body cannot effectively use the insulin it produces. Hyperglycemia is a common effect of uncontrolled diabetes and over time leads to serious damage to many of the body's systems, especially the nerves, blood vessels and immunity system. If occurs of infection in diabetic individuals, it is possible to get sepsis. Sepsis is a potentially serious medical condition that is characterized by a whole-body inflammatory state. It is a serious disease. In Taiwan, every year about three thousand eight hundred people die with sepsis. Hyperbaric oxygen (HBO) therapy is a well-established therapeutic approach increasing oxygen concentration in all tissues; improving blood flow to compromised organs; stimulating angiogenesis; increasing antioxidant enzyme expression; and aiding in the suppression of infections by enhancing white blood cell action. Our previous data showed hyperbaric oxygenation pretreatment could attenuate cardiovascular neural dysfunction in diabetic rats with sepsis, so we tried to study the effect of hyperbaric oxygenation in diabetic individuals with sepsis which is relevant to the clinical situation. In conclusion, given hyperbaric oxygen in diabetic individuals after sepsis could improve the survival rate and attenuate the decline of heart rate variability and blood pressure variability. Keyworld: hyperbaric oxygen, autonomic neuropathy, diabetic mellitus, sepsis, heart rate variability, blood pressure variability

Thesis (M. Sc.)--University of Canterbury, 2008.
Typescript (photocopy). "Supervised by Associate Professor Neville Blampied, Dr Lois Surgenor, and Dr Mike Davis." Includes bibliographical references (leaves 125-138). Also available via the World Wide Web.

碩士
國防醫學院
海底醫學研究所
87
Hyperbaric oxygenation (HBO2) has been used in clinical treatment of a number of medical conditions such as decompression sickness, CO intoxication, burn injury and so forth. The use of HBO2 is limited by its toxicity, in which free radicals formation, nitric oxide and glutamate systems seem to be involved. In this study, using both in vivo and in vitro approaches, we investigated whether free radical formation and neuronal injury are induced following single exposure to HBO2. First, SD rats, CD-1 and C57BL/6 mice were used, and the experimental group was exposed to 6ATA 100% O2, while control group to 3.5% O2 mixed air 6ATA for 20 to 30 minutes. In the HBO2-induced seizure experiment, the SD rats were pretreated with several doses of the presumable NMDA antagonist dextromethorphan prior to HBO2 exposure and recorded the seizure latency of each animal. In the in vitro study, neonatal SD rat primary cortical cultures were divided into several groups to test the possible mechanisms of HBO2-induced CNS toxicity. Our data showed that HBO2 exposure did not alter the content of dopamine in the striatum of three species of animals, with significant decrease in DOPAC of striatum of CD-1 mice. HBO2 increased the formation of 2,3-DHBA, a marker for hydroxyl radical, in the cortex of SD rats, and in the striatum and hippocampus of CD-1 mice, but not in any above-mentioned areas of C57BL/6 mice. The HBO2 exposure also decreased the formation of nitric oxide in the striatum of CD-1 mice. We also found that rats pretreated with dextromethorphan shortened the seizure latency during HBO2 exposure at higher doses. In vitro study demonstrated that HBO2 exposure resulted in lactate dehydrogenase (LDH) release and methylthiazol tetrazolium (MTT) reduction. Pretreatment with MK-801, L-NAME and DMTU protected the cells against the HBO2-induced CNS toxicity, while the SNP exacerbated the toxicity. In summary, in vivo data suggest that HBO2 can induce the formation of hydroxyl radical in specific brain areas. Additionally, there exists a species difference in the vulnerability to HBO2 exposure. In vitro studies suggest that the glutamate, nitric oxide and hydroxyl radical systems are involved in the HBO2-induced CNS toxicity. However, the exact mechanism of the effect of dextromethorphan remains to be elucidated. It is speculated that this agent may first inhibit NMDA receptor that in turn inhibits GABA interneurons and leads to the lowering of seizure threshold, or increase the cerebral blood flow that results in the increased formation of free radicals during HBO2 exposure.

碩士
慈濟大學
生理暨解剖醫學碩士班
100
The purpose of this study is to develop a model of osteoradionecrosis (ORN) in rats and to clarify the therapeutic role of hyperbaric oxygenation. Osteoradionecrosis in male Sprague–Dawley (SD) rats were induced with synchronous mandibular fractures and irradiation on the left mandible at a dose of 20 Gy. Hyperbaric oxygen (HBO) treatment in two doses of 3.0 or 2.5 atmosphere absolute pressure (ATA) for 60 min was given once daily for 20 days. Computerized tomography (CT) was used to evaluate the morphologic change of mandibles. Fresh mandibular length and weight were measured immediately after sacrifice. H&E and immunohistochemical staining of bone morphogenetic protein-2 (BMP-2) and transforming growth factor-β1 (TGF-β1) were used to demonstrate microscopic derangement and the functional outcome. Body weight loss and hair loss in the mandibular area were noticed weeks after irradiation. Atrophy of the ipsilateral incisor was remarkable in individuals underwent synchronous mandibular fractures and irradiation. CT scan also demonstrated nonunion. Significant changes of mandibular length were found. Fibrosis of bone marrow cavity with empty lacunae was observed in animals with ORN. The progression of incisor atrophy was inhibited by HBO treatment. HBO treatment also demonstrated therapeutic role in microscopic deficits. Immunohistochemical staining showed a reduction of BMP-2 and increased TGF-β1 expression in individuals with ORN. HBO therapy was able to attenuate this functional impairment of ORN. Synchronous mandibular fractures and irradiation at a dose of 20 Gy successfully induces ORN in SD rats. HBO therapy of 3.0 ATA, 60 minutes, 20 dives demonstrates therapeutic benefits in macroscopic, microscopic, and functional protein production perspectives.

博士
國防醫學院
醫學科學研究所
90
This dissertation research focused on focal cerebral ischemia, using the middle cerebral artery occlusion model in rats and mice. Studies were conducted primarily to examine influences of TGF-β family trophic factors on the sequalae of pathophysiological events. One study examined changes in the receptor for GDNF to test the hypothesis of an endogenous GDNF neuroprotective system.(Time Course Study of GFRa-1 Expression in an Animal Model of Stroke. Sarabi A, Chang CF, Wang Y, Hoffer BJ, and Morales M. Exp Neurol. 2001;170:283-289.) Previous studies have shown that intracerebral administration of glial cell line-derived neurotrophic factor (GDNF) reduces ischemia-mediated cerebral infarction. The biological effects of GDNF are mediated by GDNF-family receptor alpha-1 (GFRa-1) and c-Ret. In this study, we examined the levels of expression of GFRa-1 and c-Ret in a rat model of stroke. Adult Sprague-Dawley rats were anesthetized with chloral hydrate. The right middle cerebral artery was ligated at its distal branch for 90 min. Animals were sacrificed at 0, 6, 12, and 24 h after reperfusion and levels of expression of GFRa-1 and c-Ret mRNA were determined by in situ hybridization histochemistry. We found that GFRa-1 mRNA was up-regulated in CA3, dentate gyrus (DG), cortex, and striatum. The peak of up-regulation in DG was 6 h after reperfusion. GFRa-1 mRNA levels in CA3 were gradually up-regulated over the 24-h reperfusion period. In cortex, GFRa-1 mRNA was up-regulated at all time points; however, the peak of up-regulation was observed at 0 and 24 h after reperfusion. In striatum, an initial up-regulation of GFRa-1 was found at 0 h after ischemia. In striatum, up-regulation of c-Ret mRNA was detected as early as 0 h after reperfusion. A gradual increase was found at 6, 12, and 24 h after reperfusion. In conclusion, our results indicate that there are both regional and temporal differences in up-regulation of GFRa-1 and c-Ret after ischemia. Since GDNF is neuroprotective, up-regulation of GFRa-1 and c-Ret could enhance the responsiveness to GDNF and reduce neuronal damage. The selective up-regulation of GFRa-1 and c-Ret in different brain areas suggests that there may be regional differences in GDNF-induced neuroprotection in stroke. These changes in receptors for GDNF supports the hypothesis of an endogenous GDNF neuroprotective mechanism and extends earlier data showing a parallel upregulation of GDNF itself in stroke. A second study investigated another member of the TGF-β family, termed Bone Morphogenic Protein-6 (BMP-6) in this same rat model of focal ischemia. (Bone Morphogenetic Protein-6 Reduces Ischemia-Induced Brain Damage in Rats. Wang Y, Chang CF, Morales M, Chou J, Chen H-L, Chiang Y-H, Lin S-Z, Cadet J L, Deng X, Wang, J-Y, Chen, S-Y , Kaplan PL, and Hoffer,BJ. Stroke. 2001;32:2170-2178.) Bone morphogenetic protein-6 (BMP-6) and its receptors are expressed in adult and fetal brain.Receptors for BMP-6 are upregulated in adult brain after injury, leading to the suggestion that BMP-6 is involved in the physiological response to neuronal injury. The purpose of my study was to determine whether there was a neuroprotective effect of BMP-6 in vivo and in vitro. Lactate dehydrogenase and microtubule-associated protein-2 (MAP-2) activities were used to determine the protective effect of BMP-6 against H2O2 in primary cortical cultures. The neuroprotective effects of BMP-6 were also studied in chloral hydrate—anesthetized rats. BMP-6 or vehicle was injected into right cerebral cortex before transient right middle cerebral artery (MCA) ligation. Animals were killed for triphenyl-tetrazolium chloride staining, caspase-3 immunoreactivity and enzymatic assays, and TUNEL assay. A subgroup of animals were used for locomotor behavioral assays. Application of H2O2 increased lactate dehydrogenase activity and decreased the density of MAP-2 neurons in culture. Both responses were attenuated by BMP-6 pretreatment. Complementary in vivo studies showed that pretreatment with BMP-6 increased motor performance and generated less cerebral infarction induced by MCA ligation/reperfusion in rats. Pretreatment with BMP-6 did not alter cerebral blood flow or physiological parameters. There was decreased ischemia-induced caspase-3 immunoreactivity, caspase-3 enzymatic activity, and density of TUNEL-positive cells in ischemic cortex in BMP6-treated animals. BMP-6 thus reduces ischemia/reperfusion injury, perhaps by attenuating molecular events underlying apoptosis. Because GDNF and BMP-6 utilize entirely different receptors and intracellular second messengers, these experiments also suggest a “cocktail” of trophic factors may provide optimal neuroprotection in stroke. A third study examined another approach to provide neuroprotection for cerebral ischemia, utilizing hyperbaric oxygen. (Hyperbaric oxygen therapy for treatment of postischemic stroke in adult rats. Chang CF, Niu KC, Hoffer BJ, Wang Y, and Borlongan CV. Exp Neurol. 2000;166:298-306.) The hypothesized efficacy of hyperbaric oxygen (HBO) therapy for treatment of stroke was tested in this study. Adult rats were subjected to occlusion of the middle cerebral artery and subsequently exposed to HBO (3 atm, 2 x 90 min at a 24-h intervals. Animals terminated shortly after the second HBO treatment) or hyperbaric pressure (HBP; 3 atm, 2 x 90 min at a 24-h interval; animals terminated shortly after the second treatment) immediately after the ischemia or after a 60-min delay generally displayed recovery from motor deficits at 2.5 and 24 h of reperfusion. There was also a reduction in cerebral infarction at 24 h of reperfusion compared to ischemic animals subjected to normal atmospheric pressure. While both HBO and HBP treatments promoted beneficial effects, HBO produced more consistent protection than HBP. Treatment with HBO immediately or 60 min after reperfusion produced equally significant attenuations of both cerebral infarction and motor deficits. In contrast, protective effects of HBP treatment against ischemia were noted only when administered immediately after ischemia; there was a significantly reduced infarction volume, but only a trend toward decreased behavioral deficits. The present results demonstrate that HBO and, to some extent HBP, reduce ischemic brain damage and behavioral dysfunctions. Thus, we have validated the use of HBO in clinical situations after acute stroke. The last study in this thesis examined the mechanisms of methamphetamine facilitation of ischemic cerebral injury. (Methamphetamine potentiates ischemia/reperfusion insults after transient middle cerebral artery ligation.Wang Y, Hayashi T, Chang CF, Chiang YH, Tsao LI, Su TP, Borlongan C, and Lin SZ. Stroke. 2001;32:775-82.) Previous studies have indicated that both methamphetamine (MA) and ischemia/reperfusion injuries involve reactive oxygen species formation and activation of apoptotic mechanisms. That MA could have a synergistic or additive effect with stroke-induced brain damage is possible. The purpose of the present study was to investigate whether administration of MA in vivo would potentiate ischemic brain injury. Adult CD-1 mice were pretreated with MA or saline. Each animal was later anesthetized with chloral hydrate and placed in a stereotaxic frame. A subset of animals received intracerebral administration of GDNF. The right middle cerebral artery and bilateral carotids were transiently occluded for 45 minutes. Regional cerebral blood flow was measured by laser Doppler. Animals were sacrificed for triphenyltetrazolium chloride staining and p53 mRNA Northern blot assay after 24 hours of reperfusion. Cortical and striatal GDNF levels were assayed by ELISA. We found that pretreatment with MA increased ischemia-induced cerebral infarction. Ischemia or MA alone enhanced p53 (a pro-apoptotic molecule) mRNA expression. Moreover, MA potentiated expression of p53 mRNA in the ischemic mouse brain. MA pretreatment decreased GDNF levels in ischemic striatum. Intracerebral administration of GDNF before ischemia reduced MA-facilitated infarction. Our data indicate that MA exacerbates ischemic insults in brain, perhaps through the inhibition of GDNF-mediated pathways and suggest that MA may antagonize endogenous neuroprotective pathways as part of its mechanism of action. In addition, MA may also upregulate pro-apoptotic mechanisms, contributing to the ultimate extent of infarction. Taken together, these studies strengthen the hypothesis that apoptotic mechanisms are important in determining the extent of infarction after focal cerebral ischemia. They further provide a preclinical basis for exploring new potential therapies based on trophic proteins, particularly in the TGF-β family.

碩士
長庚大學
機械工程研究所
88
Since hyperbaric oxygen therapy (HBO) has been proved to promote osteogenesis in rabbits’ tibial lengthening , the purpose of this study was to determine the facilitating effect of hbo on bone graft healingin lumbar vertebra. Materials and methods: twenty-four male new zealand rabbits ,weighted 3.5 kg , respectively received a 2 cm2 autogeneous bone graft between the fifth and sixth lumbar transverse processes . 24 rabbits were evenly assigned into two groups, hbo group( experimental group )and normal air group ( control group). Each was then subdivided into 4 -week and 8-week groups containing 6 rabbits separately. From the third day after operation ,the rabbits in experimental groups were exposed to 4-week and 8-week hbo ,2.5 atm ,2 hours a day . While those in the control groups were set in normal air.all the rabbits underwent bone mineral density ( BMD) testing every second week and radiograqphy every fourth week. In the end of the Fourth and eighth week, they were sacrificed for l5 and l6 vertebral bodies and transverse processes ,which were subjects of biomechanical torsion testing. Results: in the hbo group, the average value of bmd and bmc increased most in the sixth week, while ceased from increasing in the eighth week. Radiographic study presented the union rate of bone graft:10/12 in 8-week HBO group, 7/12 in 8-week normal air group ,7/12 in 4-week hbo group, and 3/12 in the 4-week normal air group.Consequently, hbo promoted the union rate of lumbar bone graft.In biomechanical testing, the average values of maximum torsion from 8-week HBO group and normal air group were 3079.8 n-mm and 2661.6 n-mm respectively. A statistical difference existed between them(P=0.042). In the aspect of biomechanical rational analysis, 8-week hbo group had the greatest shearing force modulus( g ), 8-week normal air group owned the second one, 4-week HBO group followed, and 4-week normal air had the mininum g value. Conclusion: the conclusion drawn from three tests and biomechanical rationale analysis supports the hypothesis that HBO will promote the union rate of bone graft in rabbits’ lumbar vertebra . The bone graft after hbo therapy possess stronger torsion.

博士
國立清華大學
分子與細胞生物研究所
94
More than 50% of the populations have used complementary and alternative medicine (CAM) or integrative medicine (IM) at least once. From a functional standpoint, CAM/IM may be defined as interventions neither taught widely in medical schools nor generally available in hospitals. Well-designed medical researches and clinical trials are urgently needed to test the safety and efficacy of CAM/IM. Far-infrared (FIR) light therapy and hyperbaric oxygen (HBO) therapy are two emerging areas of CAM, and get much advances and utilization recently. Skin microcirculation plays an important role in chronic wound healing and hepatic ischemia-reperfusion (I/R) injury is a lethal complication met in transplantation and resection surgeries. The purpose of this study was to validate the role of FIR and HBO in skin microcirculation and hepatic I/R injury. Sixty rats were used in the FIR study. A WSTM TY301 far-infrared emitter was placed 20cm over the rats. Skin temperature and blood flow were continuously measured. Under laboratory control, the abdominal skin temperature steadily increased to 38 to 39°C, and was kept at constant temperature. The results showed that there was no significant change of skin blood flow during FIR treatment. Skin blood flow increased significantly soon after the removal of FIR emitter. The stimulating effect of skin blood flow was more significant in the rats treated with FIR for 45 min and could be sustained as long as 60 min. These findings suggested a non-thermic biological effect of FIR on skin microcirculation. The promotive effect of FIR on increasing skin blood flow was not influenced by pretreatment of APP (atropine, propranolol, phentolamine), but was suppressed by L-NAME (an eNOS inhibitor) pretreatment. In conclusion, FIR therapy exerts a NO-related biological effect to increase skin microcirculation in rats. This might bring into perspective the clinical application of FIR to treat ischemic disease by augmenting L-arginine/NO pathway. Daily treatment with one dose-HBO (90 minutes, 2.5ATA) was brought about for male Spraque-Dawley rats for one to three days before an I/R injury of liver. Hepatic expression of heat-shock protein 70 (Hsp70), total concentration of glutathione (GSH), activity of catalase, superoxide dismutase (SOD) and serum AST and ALT were estimated before and after HBO, as well as after I/R injury. The results showed that activity of hepatic catalase was decreased by one dose, but not three doses, of HBO as compared with baseline data. However, hepatic Hsp70 expression fluctuated insignificantly. AST and ALT increase less in rats preconditioned with one dose-HBO as compared with those without HBO or with 3 doses-HBO. These results showed preconditioning by one dose-HBO has protective on rat liver against subsequent ischemia-reperfusion injury. The present study is a scientific validation of CAM/IM in vascular medicine. Integrating FIR therapy and HBO therapy into conventional vascular therapies is beneficial to the patients with insufficient microcirculation and hepatic I/R injury.

碩士
國立臺灣大學
臨床醫學研究所
94
The present study is designed to reveal the possible mechanism and the therapeutic potential for hyperbaric oxygen therapy (HBO) in the treatment of sepsis , also protection effect on liver during sepsis. Immediate HBO treatment ( 2 ATA , 75 min ) was applied to assess the survival rate of septic BALB/c mice induced by LPS within 84 hours period. The changes of plasma TNF-α and IL-10 after LPS challenge were measured. The pathological change of liver at 24 hours after LPS challenge treated with/without HBO treatment were also studied. The experimental results demonstrates that: (1) immediate HBO exposure after LPS challenge increases the survival rate of mice from 25% to 75%, (2) the plasma concentration of TNF-α after LPS challenge is reduced by immediate HBO treatment, (3) HBO treatment may protect liver from septic injury. In conclusion , HBO treatment exerts beneficial effects on sepsis induced by LPS in BALB/c mouse. The possible mechanism may be due to immunomodulation effect of HBO on immune system.