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Biomedical subjects

A Cohen

Publications and source records attributed to A Cohen.

At least 55 records · Page 3Linked to original sources
PubMed2003

A new clinical condition linked to a novel mutation in lamins A and C with generalized lipoatrophy, insulin-resistant diabetes, disseminated leukomelanodermic papules, liver steatosis, and cardiomyopathy.

A-Type lamins, arising from the LMNA gene, are intermediate filaments proteins that belong to the lamina, a ubiquitous nuclear network. Naturally occurring mutations in these proteins have been shown to be responsible for several distinct diseases that display skeletal and/or cardiac muscle or peripheral nerve involvement. These include familial partial lipodystrophy of the Dunnigan type and the mandibuloacral dysplasia syndrome. The pathophysiology of this group of diseases, often referred to as laminopathies, remains elusive. We report a new condition in a 30-yr-old man exhibiting a previously undescribed heterozygous R133L LMNA mutation. His phenotype associated generalized acquired lipoatrophy with insulin-resistant diabetes, hypertriglyceridemia, hepatic steatosis, hypertrophic cardiomyopathy with valvular involvement, and disseminated whitish papules. Immunofluorescence microscopic analysis of the patient's cultured skin fibroblasts revealed nuclear disorganization and abnormal distribution of A-type lamins, similar to that observed in patients harboring other LMNA mutations. This observation broadens the clinical spectrum of laminopathies, pointing out the clinical variability of lipodystrophy and the unreported possibility of hypertrophic cardiomyopathy and skin involvement. It emphasizes the fact that the diagnosis of genetic alterations in A-type lamins requires careful and complete clinical and morphological investigations in patients regardless of the presenting signs.

Adult↗
PubMed2003

Unusual presentation of Addison's disease in Schmidt's syndrome.

A patient with Schmidt's syndrome and atypical symptoms of Addison's disease is presented. Autoimmune thyroiditis was diagnosed at the age of 12 years and then at 15 years; a diagnosis of migraine was made following 10 days of headache, visual field defects and dysarthria. One week later the patient was admitted to hospital in critical condition. Addison's disease was diagnosed and replacement therapy was introduced which brought about a rapid clinical improvement. Positive adrenal autoantibodies confirmed the diagnosis. We suggest that patients with organ-specific autoimmune disease undergo annual screening for adrenal activity, and in the event of abnormal results, adrenal autoantibody evaluation should be carried out, to avoid a life-threatening crisis caused by Addison's disease, which is often difficult to recognize due to atypical clinical presentation, as in the patient reported here.

Acute Disease↗
PubMed2003

An intelligent controller for automated operation of sequencing batch reactors.

In this paper the results are presented of original research into the automatic and "intelligent" detection of breakpoints in Dissolved Oxygen (DO) profiles. The research has been based on a large body of data collected from laboratory SBRs operating on synthetic wastewater. Two different approaches were followed to identify the endpoints. The paper analyses and evaluates the results of automatic detection on the basis of geometric features in the DO profiles. This was followed by classification of the detected breakpoints using different soft computing techniques based on Neural Network (NN), Fuzzy Neural Network (FuNN) and Evolving Fuzzy Neural Network (EfuNN) software systems for breakpoint classification. A high rate of successful detection and classification was obtained with up to 96% of the decisions made correctly. In order to overcome the limitations of this system to adapt to dynamically changing process conditions, an intelligent control model was developed by a combination between an Evolving Fuzzy Neural Net (EfuNN) combined with a logic decision unit. This system has the ability to "learn on-the-fly" and adjust its response pattern in order to maintain a high rate of successful breakpoint detection under varying changing process conditions. This software system has been sucessfully embedded on a small programmable controller for integration into larger process control systems for the operation of SBR plants.

Automation↗
PubMed2003

[A new cause of increased troponin levels: junctional tachycardia].

The authors report 4 cases of acute coronary syndromes with increased troponine levels during junctional tachycardia in patients with angiographically normal coronary arteries. ST segment changes during junctional tachycardia have no predictive value for the detection of coronary artery disease. Increased troponine, a marker of myocardial cellular necrosis, is not a sign of coronary lesions. A disequilibrium between the increased metabolic and energetic requirements of the myocardium and decreased perfusion due to the tachycardia could explain this observation. The recommended management of these patients is not to perform coronary angiography initially in the absence of cerebrovascular risk factors, but rather to document myocardial ischaemia by a non-invasive method such as echocardiography or scintigraphy.

Adult↗
PubMed2003

[Symptomatic left ventricular dysfunction and Behçet disease. Report of 2 cases].

Behçet's disease is associated with cardiac complications which may affect all three cardiac layers in 1 to 6% of cases. Although pericardial and coronary disease are the most common, the myocardium may also be affected. The clinical presentation may be left ventricular dysfunction with signs of dilated cardiomyopathy. The cause of the left ventricular dysfunction is usually coronary artery disease but it can also be inflammatory, resulting in a myocarditis with normal coronary arteries. The authors report two cases of Behçet's disease with symptomatic left ventricular dysfunction presenting as dilated cardiomyopathy with normal coronary arteries in one of the cases. Recent echocardiographic studies suggest that the incidence of myocardial disease is underestimated in this pathology: 20 to 35% of patients with Behçet's disease but no cardiac symptoms had left ventricular diastolic dysfunction. A more attentive investigation of left ventricular diastolic function in these patients should enable earlier diagnosis of this complication.

Adult↗
PubMed2002

Circular viral DNA and anomalous junction sequence in PBMC of HIV-infected individuals with no detectable plasma HIV RNA.

Closed circular (cc) forms of extrachromosomal HIV DNA are detected in patients with high viral loads; however, it is unclear whether these forms remain if virus replication is suppressed to undetectable levels by combination antiretroviral therapy. A nested primer polymerase chain reaction amplification assay was used to detect the presence of ccDNA containing two long terminal repeat sequences (2-LTR) in PBMC of patients with low or undetectable plasma HIV RNA. Fifty percent of patients with plasma RNA levels <50 copies/ml of blood had detectable 2-LTR DNA. Sequencing of the products identified normal LTR--LTR junctions in the minority of cases with the majority containing anomalies including deletions and insertions. The persistence of HIV ccDNA in patients with no detectable plasma RNA could be consistent with ongoing de novo infection of dividing cells or with stability of this form of DNA in nondividing cells.

Base Sequence↗
PubMed2002

Partial characterization of trypsin-like protease and molecular cloning of a trypsin-like precursor cDNA in salivary glands of Lygus lineolaris.

Based on substrate specificity, an alkaline pH optimum, sensitivity to selected proteinase inhibitors, and molecular analysis, we provide evidence for the presence of a trypsin-like serine proteinase in the salivary gland complex (SGC) of the tarnished plant bug, Lygus lineolaris (Palisot de Beauvois) (Heteroptera: Miridae). The predominant activity in extracts of the SGC against N(2)-benzoyl-L-arginine-p-nitroanilide (L-BApNA) was at pH 10, but a minor peak of activity also occurred at pH 5. The major BApNAase activity focused at 10.4 during preparative isoelectric focusing and was eluted with an apparent molecular weight of 23,000 from a calibrated gel filtration column. The BApNAase fraction gave a single major band when analyzed on a casein zymogram. The activity was completely suppressed by the serine protease inhibitors, phenylmethylsulfonyl fluoride (PMSF) and lima bean trypsin inhibitor. A cDNA coding for a trypsin-like protein in the salivary glands of L. lineolaris was cloned and sequenced. The 971bp cDNA contained an 873-nucleotide open reading frame encoding a 291-amino acid trypsin precursor. The encoded protein included amino acid sequence motifs that are conserved with four homologous serine proteases from other insects. Typical features of the putative trypsin-like protein from L. lineolaris included the serine protease active site (His(89), Asp(139), Ser(229)), conserved cysteine residues for disulfide bridges, the residues (Asp(223), Gly(252), Gly(262)) that determine trypsin specificity, and both zymogen signal and activation peptides. Cloning and sequencing of a trypsin-like precursor cDNA provided additional direct evidence for trypsin like enzymes in the salivary glands of L. lineolaris.

Amino Acid Sequence↗
PubMed2002

Haemophilus parainfluenzae complicating total hip arthroplasty: a rapid failure.

We present a case of rapid failure of a total hip arthroplasty caused by infection with Haemophilus parainfluenzae. The septic loosening occurred over a period of 3 months and followed a dental extraction that had not been covered by prophylactic antibiotics. This failure occurred in a previously well-functioning and asymptomatic prosthetic joint.

Aged↗
PubMed2002

Sidestream end-tidal capnometry as related to infant's position and maturation.

UNLABELLED: The objective of this study was to investigate the effect of body position on sidestream, end-tidal carbon dioxide (EtCO2) wave measurements in maturing infants. Sidestream EtCO2 wave patterns were analysed longitudinally in 20 preterm infants (born at > or = 32 wk) at 32-37 wk gestation, and in 39 full-term controls. Capnography measurements included maximal EtCO2, inspired CO2 and frequency of apnoea events (>3 s) in the supine, supine with inclination, side and prone positions. Apnoea frequency decreased during maturation, and was less prevalent in the prone than in the supine and side positions in preterm as well as in term infants (p < 0.05). No clinically significant apnoea episodes were found in our cohort. EtCO2 in term infants was lower than that in preterm infants (p < 0.05) and was not affected by sleep position in the most premature (<33 wk) and in term infants (>36 wk). EtCO2 was higher in the prone position than in supine or side positions in infants between 33 and 35 wk gestation (p < 0.01). CONCLUSION: Short apnoeic episodes decrease during maturation, and are less prevalent in the prone position in maturing infants (32-37 wk). Only modest changes in EtCO2 were recorded in the different positions during maturation.

Birth Weight↗
PubMed2002

The stuck central venous catheter: beware of potential hazards.

Many complications of attempted central venous access have been described, most related to insertion. Larger and stiffer catheters are being used more often for dialysis or massive transfusion. This case report details how one catheter was damaged during the insertion of a second catheter. The problem was discovered when the catheter could not be removed, and was subsequently removed after dissection. The reason for the difficult removal and the likely consequences of excessive force are illustrated.

Antineoplastic Agents↗
PubMed2002

[The best of 2001. Echocardiography].

The year 2001 will be characterised by the confirmation of the essential place of harmonic imaging in echocardiography, a technique which has improved in a very important fashion the definition of the endocardial contour, thus giving a more reliable analysis of the segment kinetics, as much at rest as during a physical or pharmacological stress. The advances in the field of stress echocardiography essentially give confirmation of the excellent prognostic value of this technique, either post-infarction or in chronic coronary disease, including hypertensive patients, and with left ventricular hypertrophy or a conduction disorder. The aspirations of a more quantitative approach to regional myocardial function with the aid of myocardial tissue Doppler have been partly confirmed, even if no simple parameter can yet provide information of the presence of myocardial segment viability or ischaemia. The contribution of Doppler echocardiography in the unraveling of left ventricular diastolic insufficiency is crucial, with the description of parameters allowing characterisation of the type of left ventricular diastolic function anomaly and non-invasive evaluation of the filling pressures. The advances in transoesophageal echocardiography have essentially provided a better characterisation of the thrombo-embolic risk markers in atrial fibrillation and in the search for a cardiac source of embolus. Valuable information has equally been provided in acute aortic pathology particularly in the description of symptomatology and evolution of isthmic ruptures of the aorta. The first images of transthoracic echocardiography with real time three-dimensional reconstruction have finally been presented, allowing a glimpse of the enormous possibilities of this method, compared to recorded reconstruction which is routinely performed, especially in transoesophageal echocardiography. Though myocardial contrast echocardiography continues to induce very many fundamental publications, the clinical applications are slow to convince, facing the difficulties of proposing an adequate treatment and standardising the image, and an interpretation which takes account of physiological parameters (coronary micro-circulation).

Echocardiography↗
PubMed2002

[Pneumococcal endocarditis in native valves. Three original observations in the adult].

The authors report three observations of acute pneumococcal endocarditis located in the aorta in one case, and mitral in the two other cases, admitted over a period of 4 years. Two of the three patients required surgical correction, with no surgical complications. Follow-up revealed a rare complication of infectious endocarditis linked to rupture of the head of the two anterior mitral pillars associated with an abscess. The severity of pneumococcal endocarditis is emphasised, concurring with the data from the literature. The role of echocardiography in pneumococcal septicaemia is clear; transthoracic examination is justified in every case of septicaemia, and transoesophageal echography complements this examination in case of diagnostic doubt or cardiovascular complication.

Adult↗
PubMed2002

Recommended micronutrient supplementation for institutionalized elderly.

A committee nominated by the Israel Ministry of Health examined the relevant literature and the local recommendations as well as the recommendations from other countries and suggested a daily micronutrient supplementation for institutionalized elderly living in institutions supervised by the Ministry of Health. The micronutrient preparatory, tailored for this population, is designed to contain about half the RDA for most of the vitamins and some microelements. Biotin and vitamins C, D and B12 as well as zinc, copper, chromium and molybdenum are suggested at a level higher than half the RDA, whereas fluorine, at a lower level. Major elements (calcium, magnesium and phosphorus) are excluded and should be supplied separately. Vitamin K and iron are also excluded. Fat-soluble vitamins should be microencapsulated. Micronutrient supplementation for institutionalized elderly is part of the Ministry of Health s balanced nutrition policy. The committee s recommendations are also applicable to the free-living elderly population.

Journal Article↗
PubMed2001

Routine analysis of alcohol and nonylphenol polyethoxylates in wastewater and sludge using liquid chromatography-electrospray mass spectrometry.

A wide range of alcohol and nonylphenol polyethoxylates was determined by separation on a reversed-phase liquid chromatographic column, followed by electrospray ionisation-mass spectral analysis. The compounds were separated chromatographically according to their aliphatic chain length. The mass spectral analysis functioned as a second separation step during which homologues of the ethoxylates were separated according to their polyethoxylate chain length. In this manner a truly orthogonal separation was obtained. The compounds were detected as ammonium complexes. The analysis presented is capable of qualitative and quantitative determination of a large number of ethoxylates as well as their metabolites in a single run. The method was applied to many different sample types, ranging from primary and treated wastewater to sludge. Batches of 50 real samples were routinely analysed without the need for cleaning the mass spectrometer or regeneration of the column. By utilising the extracted mass chromatograms, detection limits of 1 to 10 microg/l could be obtained for individual compounds in water samples, while the detection limits were around 100 microg/kg in sludge, depending on the degree of pollution.

Alcohols↗