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At least 253 records · Page 14Linked to original sources
PubMed2007

Alzheimer's disease.

Alzheimer's disease (AD) is the most common cause of dementia in the elderly. Currently, 4.5 million individuals in the United States are estimated to have AD, and that number is projected to increase to at least 14 million by the year 2050. AD is a major cause of disability and mortality, and its impact on health care costs, including direct and indirect medical and social service costs, is estimated to be greater than $100 billion per year. AD typically presents with an insidious decline in memory that progresses to affect language, visuospatial perception, calculations, and executive functioning. Behavioral and psychiatric symptoms are also frequent in AD. Diagnosis is determined clinically, as there is currently no laboratory test to confirm AD in life. The neuropathologic hallmarks of AD are neuritic plaques and neurofibrillary tangles. Currently available medical therapies have demonstrated modest benefits but likely do not alter disease progression. Caregivers play a large role in managing the patient and should be encouraged to seek out adult day care centers, home health services, respite care, and additional social support.

Alzheimer Disease↗
PubMed1993

[Early and presymptomatic detection of Huntington chorea].

This review summarises the techniques for early and presymptomatic testing of Huntington's chorea, a chronic neurodegenerative disorder. Presenting electrodiagnostic, neuroradiographic and neuropsychological measurements, the problem of early detection of this hereditary disorder is discussed. Presently, except for DNA-testing, none of the tests presented can reliably identify symptom-free gene carriers.

Diagnostic Imaging↗
PubMed2002

C-terminal domain phosphatase-like family members (AtCPLs) differentially regulate Arabidopsis thaliana abiotic stress signaling, growth, and development.

Cold, hyperosmolarity, and abscisic acid (ABA) signaling induce RD29A expression, which is an indicator of the plant stress adaptation response. Two nonallelic Arabidopsis thaliana (ecotype C24) T-DNA insertional mutations, cpl1 and cpl3, were identified based on hyperinduction of RD29A expression that was monitored by using the luciferase (LUC) reporter gene (RD29ALUC) imaging system. Genetic linkage analysis and complementation data established that the recessive cpl1 and cpl3 mutations are caused by T-DNA insertions in AtCPL1 (Arabidopsis C-terminal domain phosphatase-like) and AtCPL3, respectively. Gel assays using recombinant AtCPL1 and AtCPL3 detected innate phosphatase activity like other members of the phylogenetically conserved family that dephosphorylate the C-terminal domain of RNA polymerase II (RNAP II). cpl1 mutation causes RD29ALUC hyperexpression and transcript accumulation in response to cold, ABA, and NaCl treatments, whereas the cpl3 mutation mediates hyperresponsiveness only to ABA. Northern analysis confirmed that LUC transcript accumulation also occurs in response to these stimuli. cpl1 plants accumulate biomass more rapidly and exhibit delayed flowering relative to wild type whereas cpl3 plants grow more slowly and flower earlier than wild-type plants. Hence AtCPL1 and AtCPL3 are negative regulators of stress responsive gene transcription and modulators of growth and development. These results suggest that C-terminal domain phosphatase regulation of RNAP II phosphorylation status is a focal control point of complex processes like plant stress responses and development. AtCPL family members apparently have both unique and overlapping transcriptional regulatory functions that differentiate the signal output that determines the plant response.

Arabidopsis↗
PubMed1999

Dynamic and quantitative Ca2+ measurements using improved cameleons.

Cameleons are genetically-encoded fluorescent indicators for Ca2+ based on green fluorescent protein variants and calmodulin (CaM). Because cameleons can be targeted genetically and imaged by one- or two-photon excitation microscopy, they offer great promise for monitoring Ca2+ in whole organisms, tissues, organelles, and submicroscopic environments in which measurements were previously impossible. However, the original cameleons suffered from significant pH interference, and their Ca2+-buffering and cross-reactivity with endogenous CaM signaling pathways was uncharacterized. We have now greatly reduced the pH-sensitivity of the cameleons by introducing mutations V68L and Q69K into the acceptor yellow green fluorescent protein. The resulting new cameleons permit Ca2+ measurements despite significant cytosolic acidification. When Ca2+ is elevated, the CaM and CaM-binding peptide fused together in a cameleon predominantly interact with each other rather than with free CaM and CaM-dependent enzymes. Therefore, if cameleons are overexpressed, the primary effect is likely to be the unavoidable increase in Ca2+ buffering rather than specific perturbation of CaM-dependent signaling.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMedDate not supplied

Recognizing and treating body dysmorphic disorder.

BACKGROUND: Body dysmorphic disorder (BDD) is a relatively common and often-disabling obsessive compulsive spectrum disorder that often goes unrecognized in clinical practice. METHODS: The present review examines the clinical features of BDD, its relationship to other disorders, and what is known about effective treatment. RESULTS: BDD consists of a distressing and impairing preoccupation with imagined or slight defects in appearance that can focus on any body area. Insight is usually poor or absent; nearly half of patients are delusional. Typical associated behaviors include skin picking, mirror checking, excessive grooming, and camouflaging. It appears that higher doses of serotonin reuptake inhibitors and longer treatment trials than those used for many other psychiatric disorders, including depression, are often needed to effectively treat BDD. Cognitive-behavioral therapy also appears efficacious and is currently considered the psychotherapy of choice for BDD. Core techniques are cognitive restructuring, behavioral experiments, response (ritual) prevention, and exposure. CONCLUSIONS: Further research is needed to minimize the underrecognition of BDD and to improve proper treatment. Because of the high rates of comorbidity in patients with BDD, treatment studies need to include subjects with co-occurring disorders and thereby attempt to understand how these other disorders affect treatment response. Finally, more research needs to address the pathophysiology of BDD (for example, by incorporating imaging and genetics).

Cognitive Behavioral Therapy↗
PubMed2001

Assessment of inflammatory myositis.

The assessment of disease activity and damage in patients with idiopathic inflammatory myositis remains inadequate. In this review we describe current approaches to the assessment of disease activity and damage. These include serologic, biochemical, radiographic, and histologic approaches. None of these methods are individually effective in differentiating disease activity from damage. Invariably combinations of these methods are needed to comprehensively assess the extent of both muscular and extramuscular disease. Recent developments (in serology, imaging, and genetics) are mentioned. These may prove to be useful in assessing the full extent of idiopathic inflammatory myositis; however, they are not widely available at present and are confined to research studies

Blood↗
PubMed1996

New developments in obsessive-compulsive disorder research: implications for clinical management.

Over the past decade, epidemiological, phenomenological, pharmacological, neurobiological, brain imaging and genetic research has contributed to a substantial change in our understanding of obsessive-compulsive disorder (OCD). Once regarded as a rare psychodynamic illness, OCD is now recognized as a common condition affecting 2-3% of the population. Better recognition combined with the demonstrated efficacy of serotonin reuptake inhibitors, such as clomipramine and the selective serotonin reuptake inhibitors (SSRIs), has dramatically improved the prognosis of this disorder, which exacts a considerable personal and economic burden. While the aetiology is still not understood, increasingly sophisticated research techniques are enabling us to begin to uncover the underlying pathophysiology of this illness. This paper reviews some of the recent developments which have enhanced our understanding of OCD and considers their potential impact on clinical management.

Evaluation Studies as Topic↗
PubMed2000

Prodromal schizophrenia and atypical antipsychotic treatment.

Early recognition and intervention in psychosis is the focus of more intensive research. In this paper, we critically review the ideas that have emerged in this field. We also propose a model or hypothesis for testing in the prodromal phase of schizophrenia. Attention to practical and ethical issues, particularly with the use of atypical antipsychotics in one arm of the protocol, is addressed. Studies by Yung and Falloon describe prodromal intervention with psychosocial strategies and time-limited low potency neuroleptics, respectively, that suggest benefits of such a model. Although we have respect for the DSM system, this paper is written more from a Bleulerian than Kraepelinian perspective in that we emphasize affective, cognitive, and negative symptoms in addition to positive symptoms. The paper recognizes the strong conceptual disagreements implicit in this area stemming not only from Kraepelin and Bleuler but work from the 1930s by Cameron. The clinical research advocated is timely in that the atypicals are more congruent to the Bleulerian conception with a neurodevelopmental hypothesis of schizophrenia. We also have exciting new imaging and genetic technologies to refine our concepts of schizophrenia and its prodromal and premorbid phases.

Age of Onset↗
PubMed1998

Current concepts in pancreatic cancer: symposium summary.

This recent symposium featured speakers from several clinical and research disciplines. Among the findings: peptic ulcer disease is a significant predisposing risk factor (odds ratio = 3.9) for pancreatic cancer; as many as 50% of all intraductal papillary mucinous neoplasms are associated with invasive adenocarcinomas; alteration of gene expression via methylation of a gene promotor region constitutes a potentially reversible method of tumor suppressor gene inactivation; > 400 transcriptional alterations of gene expression have been identified for pancreatic cancer; some common molecular markers such as p53 and HER-2/neu may be related to morphologic alterations of in situ neoplasia and to transcriptional alterations of gene expression rather than mutational events; epidermal growth factor (EGF), transforming growth factor beta (TGF-beta), and related molecules may modulate gene transcription via "autocrine" or "paracrine" mechanisms; several cytokines, amylin (islet amyloid polypeptide), and other cachexia factors are responsible for paraneoplastic peripheral insulin resistance, ineffective utilization of glucose, and profound cachexia. In the clinical diagnostic arena: the World Health Organization established a standard nomenclature for intraductal papillary mucinous neoplasms, mucinous cystic tumors, intraductal mucinous hyperplasias, and solid pseudopapillary tumors; focal glandular differentiation may be commonly identified within pancreatic endocrine neoplasms (islet cell tumors) while not necessarily implying an unfavorable prognosis typical of ductal adenocarcinomas; positron emission tomography scanning may be used for evaluation of early tumor response to novel chemotherapeutic regimens; helical computed tomography (CT) is the state of the art in preoperative imaging for pancreatic cancer; neoadjuvant 5-fluorouracil (5-FU)-based chemoradiation in 39 "resectable" patients provided a median survival of 19 months, actuarial 4-year survival of 19%, and improved local tumor control; gemcitabine has shown promise in alleviating tumor-related symptoms with a significantly better "clinical benefit response" than single agent 5-FU (23.8 vs. 4.8%, p = 0.0022) based on change in pain intensity, daily analgesic consumption, performance status, and weight; a significant survival advantage was demonstrated in patients treated with conventional therapies whose tumors expressed p21WAF-1, an important inhibitor of cell cycle progression and downstream molecule of p53 and TGF-beta; a p21-adenovirus (rAD-p21) gene therapy resulted in significant growth inhibition of pancreatic cancer cell lines in tissue culture, and development of a successful SCID mouse-human pancreatic adenocarcinoma xenograft model provided an animal model for preclinical trials of rAD-p21.

Antineoplastic Agents↗
PubMed2001

Psychiatric issues in epilepsy.

In recent years there has been considerable research interest at the interface between epilepsy and psychiatry. Topics of interest include the epidemiology of psychiatric co-morbidity in epilepsy; clinical syndromes at this interface and their classification; the relationship between cognitive dysfunction and psychiatric co-morbidity; biological mechanisms that mediate such co-morbidity, especially with developments in imaging and genetic research; the association between temporal lobe surgery, vagus nerve stimulation, and other non-pharmacological treatments, and the development of such co-morbidity; the contribution of anticonvulsant drugs towards the development of psychiatric co-morbidity; quality of life and other psychosocial issues; and non-epileptic attack disorder. In this review, papers on these psychiatric issues in epilepsy, with a focus on those published in the past year (October 1999 to October 2000) are critically evaluated, and some important current issues at this interface are considered in detail.

Anticonvulsants↗
PubMed2001

Management of optic neuritis and multiple sclerosis.

Optic neuritis and multiple sclerosis (MS) are common causes of visual and neurologic dysfunction in young adults. Advances in magnetic resonance imaging, molecular genetics, and neuroimmunology have increased our understanding of the pathophysiology underlying both disorders. Corticosteroids remain the mainstay of treatment of optic neuritis, but alternate dosages and routes of administration are undergoing investigation. The available therapies for MS have expanded, and there is evidence that early intervention is beneficial. Treatments for MS show sustained efficacy, but are not curative, and adjunctive treatments may prove valuable in patients with progressive visual and neurologic disability.

Humans↗
PubMed2005

Current trends in the diagnosis and management of head and neck paragangliomas.

PURPOSE OF REVIEW: The purpose of this review is to provide an overview of the diagnosis and management of head and neck paragangliomas. RECENT FINDINGS: The review will focus on three main areas of interest: genetics, newer imaging modalities, and management with radiation therapy. SUMMARY: The succinate dehydrogenase enzyme complex is important in the pathogenesis of paragangliomas. Magnetic resonance angiography and functional imaging have become very helpful in diagnosing these tumors. Surgery is still the mainstay of therapy, but conventional or stereotactic radiotherapy seems to be a very safe option in very large or inoperable tumors.

Carotid Body Tumor↗
PubMed2001

Epigenetic randomness, complexity and singularity of human iris patterns.

We investigated the randomness and uniqueness of human iris patterns by mathematically comparing 2.3 million different pairs of eye images. The phase structure of each iris pattern was extracted by demodulation with quadrature wavelets spanning several scales of analysis. The resulting distribution of phase sequence variation among different eyes was precisely binomial, revealing 244 independent degrees of freedom. This amount of statistical variability corresponds to an entropy (information density) of about 3.2 bits mm(-2) over the iris. It implies that the probability of two different irides agreeing by chance in more than 70% of their phase sequence is about one in 7 billion. We also compared images of genetically identical irides, from the left and right eyes of 324 persons, and from monozygotic twins. Their relative phase sequence variation generated the same statistical distribution as did unrelated eyes. This indicates that apart from overall form and colour, iris patterns are determined epigenetically by random events in the morphogenesis of this tissue. The resulting diversity, and the combinatorial complexity created by so many dimensions of random variation, mean that the failure of a simple test of statistical independence performed on iris patterns can serve as a reliable rapid basis for automatic personal identification.

Functional Laterality↗
PubMed2006

Childhood pancreatitis.

Inflammation of the pancreas has many presentations in children and adolescents. The etiology is often elusive, with a great number of cases being idiopathic. However, there have been a number of recent advances in the areas of cell biology, genetics and imaging technology, which should be highlighted. Herein is provided a review for the reader with particular emphasis on some of these newer advances.

Acute Disease↗
PubMed2006

Imaging clathrin dynamics in Drosophila melanogaster hemocytes reveals a role for actin in vesicle fission.

Clathrin-mediated endocytosis (CME) is essential for maintaining many basic cellular processes. We monitored the dynamics of clathrin in live Drosophila melanogaster hemocytes overexpressing clathrin light chain fused to enhanced green fluorescent protein (EGFP) using evanescent wave microscopy. Membrane-associated clathrin-coated structures (CCS) constitutively appeared at the peripheral filopodial membrane, moved centripetally while growing in intensity, before being eventually endocytosed within a few tens of seconds. This directed CCS traffic was independent of microtubules but could be blocked by latrunculin A. Taking advantage of available mutants of Drosophila, we expressed clathrin-EGFP in wasp and shibire mutant backgrounds to study the role of actin and dynamin in CCS dynamics and CME in hemocytes. We show that actin plays an essential role in CME in these cells, and that actin and dynamin act at the same stage, but independent of each other. Drosophila melanogaster hemocytes proved to be a promising model system to uncover the molecular events during CME in combining live-cell imaging and genetic analysis.

Actins↗
PubMed2006

Role of astrocytes in cerebrovascular regulation.

Astrocytes send processes to synapses and blood vessels, communicate with other astrocytes through gap junctions and by release of ATP, and thus are an integral component of the neurovascular unit. Electrical field stimulations in brain slices demonstrate an increase in intracellular calcium in astrocyte cell bodies transmitted to perivascular end-feet, followed by a decrease in vascular smooth muscle calcium oscillations and arteriolar dilation. The increase in astrocyte calcium after neuronal activation is mediated, in part, by activation of metabotropic glutamate receptors. Calcium signaling in vitro can also be influenced by adenosine acting on A2B receptors and by epoxyeicosatrienoic acids (EETs) shown to be synthesized in astrocytes. Prostaglandins, EETs, arachidonic acid, and potassium ions are candidate mediators of communication between astrocyte end-feet and vascular smooth muscle. In vivo evidence supports a role for cyclooxygenase-2 metabolites, EETs, adenosine, and neuronally derived nitric oxide in the coupling of increased blood flow to increased neuronal activity. Combined inhibition of the EETs, nitric oxide, and adenosine pathways indicates that signaling is not by parallel, independent pathways. Indirect pharmacological results are consistent with astrocytes acting as intermediaries in neurovascular signaling within the neurovascular unit. For specific stimuli, astrocytes are also capable of transmitting signals to pial arterioles on the brain surface for ensuring adequate inflow pressure to parenchymal feeding arterioles. Therefore, evidence from brain slices and indirect evidence in vivo with pharmacological approaches suggest that astrocytes play a pivotal role in regulating the fundamental physiological response coupling dynamic changes in cerebral blood flow to neuronal synaptic activity. Future work using in vivo imaging and genetic manipulation will be required to provide more direct evidence for a role of astrocytes in neurovascular coupling.

Animals↗
PubMed2005

Fictive swimming motor patterns in wild type and mutant larval zebrafish.

Larval zebrafish provide a unique model for investigating the mechanisms involved in generating rhythmic patterns of behavior, such as swimming, due to the array of techniques available including genetics, optical imaging, and conventional electrophysiology. Because electrophysiological and imaging studies of rhythmic motor behaviors in paralyzed preparations depend on the ability to monitor the central motor pattern, we developed a fictive preparation in which the activity of axial motor neurons was monitored using extracellular recordings from peripheral nerves. We examined spontaneous and light induced fictive motor patterns in wild type and mutant larval zebrafish (4-6 days post-fertilization) paralyzed with curare. All spontaneous and light-induced preparations produced alternation of motor activity from side-to-side (mean contralateral phase = 50.7 +/- 7.0%; mean burst frequency = 35.6 +/- 4.7 Hz) and a progression of activity from head-to-tail (mean ipsilateral rostrocaudal delay = 0.8 +/- 0.5 ms per segment), consistent with lateral undulation and forward propulsion during swimming, respectively. The basic properties of the motor pattern were similar in spontaneous and light-induced swimming. This fictive preparation can be used in combination with conventional electrophysiological and imaging methods to investigate normal circuit function as well as to elucidate functional deficits in mutant lines. Toward this end, we show that two accordion class mutants, accordion and bandoneon, have alternating activity on opposite sides of the body, contradicting the hypothesis that their deficit results from the absence of the reciprocal glycinergic inhibition that is typically found in the spinal cord of swimming vertebrates.

Action Potentials↗