Книги з теми "Cell autonomy"

This is a digitally enhanced text. Readers can also see the coverage of this topic area in the second edition of Neuroglia. The second edition of Neuroglia was first published digitally in Oxford Scholarship Online and the bibliographic details provided, if cited, will direct people to that version of the text. Readers can also see the coverage of this topic area in the ...

This chapter reviews recent literature on uses, effects, and gratifications of media during emerging adulthood. The authors examine traditional media forms, including television, films, video games, music, and books, and also newer media, such as cell phones, social networking sites, and other Internet use, finding that emerging adults spend more time using media than they spend doing any other activity, with most time being spent on the Internet and listening to music. They also find that exposure to certain types of media content can influence both positive and negative outcomes in emerging adulthood, including aggressive and prosocial behavior, body image, sexual behavior, friendship quality, and academic achievement. The authors show that emerging adults use media to gratify certain needs, key among them entertainment, autonomy, identity, and intimacy needs. The authors discuss areas for future research involving media and emerging adulthood.

Parkinson disease is a neurodegenerative disorder characterized clinically by tremor, rigidity, bradykinesia, and postural instability and pathologically by loss of nigrostriatal neurons and deposition of alpha-synuclein in neuronal cell bodies and neuritis. Non-motor symptoms such as psychiatric disorders, cognitive abnormalities, sleep dysfunction, autonomic dysfunction, and sensory manifestations are also common. This chapter gives a broad overview of this disorder. Sections cover pathophysiology, genetics, clinical manifestations, and disease course. The chapter also briefly discusses how to make the diagnosis, and alternative conditions that should be considered.

The complexity of fish behaviour and information processing indicates high levels of neural, anatomical and functional organization. Neural cells are conducting neurons and neuroglia with putative support and physiological roles. Neuronal conduction, synaptic transmission, reflexes and neuropils are factors in integrative activity and information processing. Fish nervous systems are organized into central (brain and spinal cord) and peripheral (including autonomic) components. Interestingly the structure and function of the fish optic tectum have been considered comparable to those of the tetrapod cerebral cortex. Also of interest are the bilaterally paired large Mauthner fibres in the teleost central nervous system, which mediate startle responses. The autonomic nervous system in fish occupies a pivotal position amongst vertebrates, including uncertainty about the existence of a posterior parasympathetic component. The trend is to regard it in terms of spinal autonomic (sympathetic) cranial autonomic (parasympathetic) and enteric systems. Accounts of the autonomic control of individual effector systems are included.

How the Amish have adopted certain digital tools in ways that allow them to work and live according to their own value system. The Amish are famous for their disconnection from the modern world and all its devices. But, as Lindsay Ems shows in Virtually Amish, Old Order Amish today are selectively engaging with digital technology. The Amish need digital tools to participate in the economy—websites for ecommerce, for example, and cell phones for communication on the road—but they have developed strategies for making limited use of these tools while still living and working according to the values of their community. The way they do this, Ems suggests, holds lessons for all of us about resisting the negative forces of what has been called “high-tech capitalism.” Ems shows how the Amish do not allow technology to drive their behavior; instead, they actively configure their sociotechnical world to align with their values and protect their community's autonomy. Drawing on extensive ethnographic fieldwork conducted in two Old Order Amish settlements in Indiana, Ems explores explicit rules and implicit norms as innovations for resisting negative impacts of digital technology. She describes the ingenious contraptions the Amish devise—including “the black-box phone,” a landline phone attached to a device that connects to a cellular network when plugged into a car's cigarette lighter—and considers the value of human-centered approaches to communication. Non-Amish technology users would do well to take note of Amish methods of adopting digital technologies in ways that empower people and acknowledge their shared humanity. The open access edition of this book was made possible by generous funding from Arcadia – a charitable fund of Lisbet Rausing and Peter Baldwin.

Neurological disorders of the brain, spine, and peripheral nervous system are examined. Symptoms and signs related to disorders of the cerebral cortex may lead to alterations in cognition and consciousness. Unilateral neurologic symptoms involving a single neurologic symptom commonly localize to the cerebral cortex. Abnormalities of speech and language are localized to the dominant cerebral hemisphere, whereas abnormalities of the nondominant hemisphere may lead to visuospatial deficits, confusion, or neglect of the contralateral side of the body. The hypothalamus is important in many functions that affect everyday steady-state conditions, including temperature regulation, hunger, water regulation, sleep, endocrine functions, cardiovascular functions, and regulation of the autonomic nervous system. Cortical and subcortical abnormalities may also lead to visual system deficits, usually homonymous visual defects of the contralateral visual field. Sensory levels, signs of anterior horn cell involvement, and long-tract signs in the posterior columns or corticospinal tract suggest a spinal cord lesion.

Diseases that affect the neuromuscular junction (NMJ) interfere with normal nerve transmission and cause weakness of voluntary muscles. The two most commonly encountered are acquired myasthenia gravis (MG) and the Lambert–Eaton myasthenic syndrome (LEMS). Acquired MG is an autoimmune disease in which antibodies are directed towards receptors at the NMJ. In 85% of patients, IgG antibodies against the postsynaptic acetylcholine receptor (AChR) are found (seropositive MG). The thymus gland appears to be involved in the production of these which cause an increase rate of degradation of AChR resulting in a decreased receptor density resulting in a reduced postsynaptic end-plate potential following motor nerve stimulation and leading to muscle weakness. Although all voluntary muscles can be affected, ocular, bulbar, respiratory, and proximal limb weakness predominates. In the majority of seronegative patients, an antibody directed towards a NMJ protein called muscle specific tyrosine kinase (MUSK) is found. Anti-MUSK MG is characterized by severe bulbar and respiratory muscle weakness. Diagnosis of MG requires a high degree of clinical suspicion coupled with pharmacological and electrophysiological testing, and detection of the various causative antibodies. Treatment of MG involves enhancing neuromuscular transmission with long-acting anticholinesterase agents and immunosuppression. Acute exacerbations are treated with either plasma exchange or intravenous immunoglobulin. Myasthenic crisis is associated with severe muscle weakness that necessitates tracheal intubation and mechanical ventilation. LEMS is an autoimmune disease in which IgG antibodies are directed towards the pre-synaptic voltage-gated calcium channels at the NMJ. It is often associated with malignant disease (usually small cell carcinoma of the lung). Autonomic dysfunction is prominent and patients show abnormal responses to neuromuscular blocking drugs.

This chapter describes the appropriate clinical approach to take when presented with a patient reporting a neurological symptom. Just under 10 per cent of the population consult their general practitioner about a neurological symptom each year in the United Kingdom. About 10 per cent of these are referred for a specialist opinion, usually to a neurologist. Nine conditions account for roughly 75 per cent of general neurological referrals and are diagnosed initially on purely clinical grounds, with the other 25 per cent representing the full range of other, potentially very rare, neurological disorders.This chapter underlines the importance of a thorough and informative history to achieve successful diagnosis. Crucial facets for a good history include information on the time course of symptom development, whether symptoms are negative or positive, previous neurological history (both personal and familial), as well as other potentially contributory general medical disorders. The general neurological examination is also described, as are specific examination manoeuvres that may be added to the general neurological examination in specific clinical circumstances.Reflexes play an important role in diagnostic neurology because they reflect the integrity of, or alterations in, the neural structures responsible for their arc. Loss of a reflex may be due to interruption of the afferent path by a lesion involving the first sensory neurone in the peripheral nerves, plexuses, spinal nerves, or dorsal roots, by damage to the central paths of the arc in the brainstem or spinal cord, by lesions of the lower motor neurone at any point between the anterior horn cells and the muscles, of the muscles themselves, or by the neural depression produced by neural shock. In clinical practice, the most useful and oft-elicited reflexes are the tendon reflexes of the limbs, the jaw jerk, the plantar response, the superficial abdominal reflexes, the pupil-light response, and in infants, the Moro reflex. The place of these particular reflexes in the routine neurological examination is outlined, and the elicitation and significance of these reflexes and of a wide variety of others which are used occasionally are described.Examinations that allow localization lesions that are responsible for muscle weaknesses and the assessment of somatosensory abnormalities are described, as are neurological disorders that result in identifiable gait disorders. The clinical signs and examinations relevant to autonomic disorders are also discussed.Intensive care may be required for patients critically ill either as a result of primary neurological disease, or in those in whom a neurological disorder is a component of, or secondary to, a general medical disorder. Indications for admission to neurological intensive care have been defined (Howard et al. 2003): impaired consciousness, bulbar muscle failure, severe ventilatory respiratory failure, uncontrolled seizures, severely raised intracranial pressure, some monitoring and interventional treatments, and unforeseen general medical complications. Naturally specific treatments indicated for the particular diagnosis should be instituted along with general intensive care measures.Finally, the discussion of diagnoses of chronic or terminal conditions with patients is discussed, with particular focus on the best way to present the diagnosis to the patient.