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Biomedical subjects

M Roth

Publications and source records attributed to M Roth.

At least 235 records · Page 13Linked to original sources
PubMed1990

A follow-up study of dementia diagnosed in the community using the Cambridge Mental Disorders of the Elderly Examination.

Elderly Cambridge residents diagnosed as demented using the Cambridge Mental Disorders of the Elderly Examination (CAMDEX) were reviewed approximately 12 months later. Diagnoses were confirmed in 133 of 137 surviving cases (97%). Subjects said to have minimal dementia (cognitive impairment insufficient to warrant a diagnosis of dementia proper) had a varied outcome. Only 6 out of 29 survivors showed progressive intellectual deterioration and 13 were reclassified as normal. Subjects passed as normal in the first year of the study were reviewed using the Mini-Mental State Examination. We cannot be certain how many were actually dementing, but our findings suggest that only a small number of false negative diagnoses were made in the first year of the study.

Aged↗
PubMed1990

PAF-dependent phosphatidylinositol turnover in platelets: differences between asthmatics and normal individuals.

The effects of nebulized platelet-activating factor (PAF) on the pulmonary and cardiovascular systems, and on the platelets present in peripheral blood were investigated in 9 normal individuals and in 6 patients with asthma and 3 individuals with lyso-PAF. The inhalation of PAF caused an acute decrease in specific airway conductance. The circulatory system parameters monitored showed an increase in heart rate while blood pressure decreased in both groups that were studied. The inhalation of PAF led to a significant increase in the differential count of polymorphonuclear leukocytes after 15 min; the count returned to the initial level after 24 h. However, the platelet count remained unchanged. The phosphatidylinositol (PI) turnover and in particular the formation of 1,4,5-inositoltrisphosphate (IP3) in platelets were investigated after PAF inhalation. It also mediated an increase in intracellular free calcium concentration, [Ca2+]i, in response to a second challenge with exogenous PAF. The basal levels of IP3 and [Ca2+]i were significantly greater in the platelets of patients with asthma than in those of normal individuals (p less than 0.01). Platelets that had been isolated from normal and asthmatic subjects had a higher concentration of IP3 and [Ca2+]i in the platelets after an in vitro exposure to PAF. After an inhalation challenge with PAF, the platelets of both the normal individuals and the patients with asthma showed a specific refractoriness to the in vitro exposure to PAF. Perhaps, this is an explanation for the PAF-dependent tachyphylaxis that is commonly observed in both normal and asthmatic individuals.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗
PubMed1990

Problems reported by relatives in a community study of dementia.

The supporters of 120 demented elderly people completed rating scales of the frequency and severity of the problems they faced, the amount of strain they experienced and their psychological well-being. Problems and strain increased with the degree of dementia. Problems relating to physical dependency, forgetfulness and inertia were relatively common, while disturbed behaviours were relatively uncommon. Physical dependency and disturbed behaviour were less well tolerated than forgetfulness and inertia, but all problem categories were positively associated with measures of strain. Wives reported more problems and strain than husbands, and co-resident children were under greater strain than children who lived independently.

Activities of Daily Living↗
PubMed1990

Bleomycin primes monocytes-macrophages for superoxide production.

Bleomycin (BLM) induces lung inflammation and subsequent fibrosis in humans and animal models. We hypothesized that monocytes-macrophages represent target cells for BLM toxicity and participate in the initial stages of pulmonary inflammation. We developed an animal model of early lung lesions using systemic administration of BLM (2 U.100 g-1 body weight over 5 days) (BLM-rats). We observed a significant decrease in body weight and in serum angiotensin converting enzyme activity in BLM-rats as compared to matched controls rats, but no evidence of fibrosis was seen in optic microscopy of the lungs from BLM-rats. In contrast, electron microscopy revealed accumulation of intracapillary polymorphonuclear leucocytes and unusual presence of eosinophils. We then investigated the in vivo effects of BLM on the respiratory burst of monocytes-macrophages. As compared to control rats, production of superoxide (O2-) by alveolar macrophages from BLM-rats was increased upon stimulation with either phorbol myristate acetate (21.04 +/- 2.78 versus 11.45 +/- 2.26 nmol.10(6) cells.20 min-1, p less than 0.05) or opsonized zymosan (9.35 +/- 0.87 versus 7.03 +/- 0.66 nmol.10(6) cells.20 min-1, p less than 0.05). We also found in BLM-rats an increased number of circulating monocytes and an increased production of O2- by these cells. Monocytes-macrophages may represent a target cell in the early events of BLM toxicity in vivo and the increased production of O2- by these cells participates in tissue injury in pulmonary fibrosis.

Animals↗
PubMed1990

Molecular analysis of neurofibrillary degeneration in Alzheimer's disease. An immunohistochemical study.

Antibodies directed against three regions of tau, ubiquitin, and B-amyloid were used in a histologic study of neurofibrillary degeneration in Alzheimer's disease to distinguish two populations of neurofibrillary tangles. Intracellular tangles were immunolabeled exclusively by two antibodies raised against antigens in the fuzzy coat of the paired helical filament (PHF). Extracellular tangles were distinguished by selective immunolabeling with a monoclonal antibody raised against antigens in the PHF core. This was associated with removal of the fuzzy coat and exposure of PHF-core epitopes. In the transition from intracellular to extracellular compartments in vivo, tangles appeared to undergo changes similar to protease digestion in vitro. The transition was associated with the appearance of amyloid immunoreactivity. These findings suggest that tangle degradation occurs in a series of distinct stages, including ubiquitination of some unknown molecule, a change in tau immunoreactivity, and partial proteolysis of tangle-bound tau in extracellular tangles.

Aged↗
PubMed1990

[Disseminated candidiasis in a calf. Case report].

The pathological-anatomical and histological examinations of different organs from a calf that died at the age of 9 weeks indicated a disseminated candidiasis. Candida albicans was isolated from brain, lung, liver, spleen, kidney, intestinal lymph nodes and small intestinal contents. The antibiotics administered to the calf by the owner probably initiated the disseminated candidiasis.

Animals↗
PubMed1990

[Metabolism of bile pigments in the intestine].

This review discusses the knowledge on the transformation of bilirubin into urobilinoids before its elimination from the organism. The following aspects are presented: mechanism of bilirubin reduction by anaerobic intestinal bacteria, structure of the resulting urobilinoids, and enterohepatic circulation of the latter. Investigations on the reduction of bilirubin by intestinal bacteria in vitro are described, and the diagnostic value of urobilinoids determination is discussed.

Animals↗
PubMed1990

Prevalence and intensity of Pseudodelphis oligocotti n. gen., n. sp. (Dracunculoidea; Guyanemidae) in the tidepool sculpin, Oligocottus maculosus (Scorpaeniformes; Cottidae).

Pseudodelphis oligocotti n. gen., n. sp. (Dracunculoidea; Guyanemidae) is described from the tidepool sculpin, Oligocottus maculosus (Scorpaeniformes; Cottidae), from various localities in coastal British Columbia. The species is placed in Guyanemidae because of its reduced buccal capsule, divided esophagus, functional vulva, and single ovary. It is distinguished from Guyanema, the only other genus in the family, by the absence of caudal alae and the arrangement of caudal papillae in the male. Females of the new genus are distinguished from those of Guyanema by the presence of a blind uterine diverticulum, without associated oviduct and ovary, extending anteriorly from the junction of the posterior uterus and vagina, and a more posteriorly positioned vulva. Fish were sampled every 2 wk throughout 1988. Worms were overdispersed in the host population. Prevalence and mean intensity of infection were highest from February to March.

Animals↗
PubMed1989

Increase of creatine kinase and lactate dehydrogenase in the serum of rats submitted to experimental intestinal infarction.

Acute intestinal ischemia is a severe condition for which no early biochemical index exists at present. We have investigated the effect of experimental intestinal infarction in the rat on the serum concentration of total creatine kinase, creatine kinase BB and total lactate dehydrogenase. Suppression of blood supply from the superior mesenteric artery resulted in marked increases of total creatine kinase, of its BB isoenzyme, and of total lactate dehydrogenase. Whereas total creatine kinase and total lactate dehydrogenase cannot be regarded as specific markers of the intestine, creatine kinase BB could prove to be more specific in view of its limited tissue distribution.

Animals↗
PubMed1989

Biotinylation: a simple method for labelling complement component C8 with preservation of functional activity.

Biotinylation of human C8 with the water-soluble biotin derivative biotinylamidohexanoic acid, N-hydroxysulfosuccinimide ester is an excellent method for labelling this terminal complement component with preservation of its functional activity. The biotinylated product can be detected both in native form and also following its incorporation into the terminal complement complexes. Detection assays include Western blotting, crossed immunoblotting, ELISA, and immunocytochemistry. Biotinylation is an attractive alternative method for labelling C8 and may be used for detecting and quantifying C8 and C5b-9 complexes in their soluble and membrane-bound forms.

Biotin↗
PubMed1989

Penetrating injuries involving the anterior cranial fossa.

Penetrating injuries of the anterior cranial fossa may result in permanent neurologic changes or even death if injuries are unrecognized and remain untreated. The diverse etiologies of such injuries are reviewed, as well as their diagnosis, treatment and prognosis.

Cerebrospinal Fluid Rhinorrhea↗
PubMed1989

Recombinant human interleukin-1 beta decreases serum carboxypeptidase N and modifies serum amino acid concentrations in rats.

The effects of recombinant human interleukin-1 beta (rhIL-1 beta) on various serum constituents were studied following subcutaneous injection (12.5 or 125 micrograms/kg) in female Wistar rats. Protein electrophoresis and the determination of the serum concentrations of carboxypeptidase N (CPN), aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, aldolase, total proteins, iron, urea, creatinine, and several amino acids were performed 12, 24, and 72 hr after injection. With both doses of rhIL-1 beta, iron, albumin, CPN, and lysine were significantly decreased whereas alpha 2-globulin, urea, and creatinine were significantly increased 12 hr after administration. Iron and CPN were still low after 24 hr but returned to normal levels after 72 hr. With the higher dose of rhIL-1 beta, only alanine and phenylalanine levels were increased after 12 and 72 hr, taurine after 12 hr, and methionine after 24 hr. There were no biochemical or histological signs of hepatotoxicity. The findings indicate that rhIL-1 beta produces a reversible alteration of various biochemical plasma constituents without any apparent signs of cytotoxicity. Moreover, the decrease in CPN observed may influence the degradation of inflammatory peptides.

Amino Acids↗
PubMed1989

Age-related decrease in an early step of DNA-repair of normal human lymphocytes exposed to ultraviolet-irradiation.

A monoclonal antibody-based immunoassay has been used to detect age-related changes in the rate of loss of photoproduct antigenicity from the DNA of peripheral blood lymphocytes irradiated with 10 J m-2 uv-C. Lymphocytes were obtained from 75 healthy volunteers whose ages ranged from 14 months to 82 years. The samples were divided by age decades into groups of 10 individuals, except the first decade which contained only 5 individuals. The mean loss of antigenicity +/- 1 standard deviation was determined for each group at 10, 30, and 60 min after irradiation. The data were analyzed by Mann-Whitney U test and by the Kruskal-Wallis test. After a recovery period of 10 min the loss of antigenicity was most rapid in group I (0-9 years), less rapid in group II (10-19 years), and least rapid in all other groups. The differences between groups became less at 30 min and were not significant at 60 min incubation. These data obtained from normal cells concur with our previous conclusions, that reductions in the rate of loss of antigenicity in nondiseased cells isolated from patients with melanoma and dysplastic naevus syndrome reflect genetic abnormalities in these patients.

Adolescent↗
PubMed1989

An insertion mutation in the pol gene of Moloney murine leukemia virus results in temperature-sensitive pol maturation and viral replication.

An insertion mutation in the pol gene of Moloney murine leukemia virus (M-MuLV) was found to render the virus temperature-sensitive for replication. A provirus containing a 12-bp insertion at the boundary between the reverse transcriptase (RT) and integrase (IN) domains induced the formation of mutant virions containing a partially processed RT-IN fusion protein. Some proteolytic processing to form mature RT and IN was observed at 32 degrees, but only aberrantly processed proteins were detected at 39 degrees. The uncleaved precursor was found to exhibit DNA polymerase activity, even though it could not support replication of the virus in vivo at 39 degrees.

Animals↗
PubMed1989

Quantitative whole-body autoradiographic determination of tacrine tissue distribution in rats following intravenous or oral dose.

Tacrine (1,2,3,4-tetrahydro-9-acridinamine) has been employed in diverse clinical situations but has recently been of considerable interest for the treatment of cognitive deficits associated with senile dementia (Alzheimer's disease). The present studies examined tissue distribution of radiolabeled tacrine by quantitative whole-body autoradiography. Tacrine radioequivalents were widely distributed to tissue following iv or peroral dose, with an apparently prolonged absorption phase following po dose. The presence of high levels of activity in kidneys and ureters indicates a major role for urinary excretion, but there is also evidence for biliary excretion and direct secretion of compound or metabolites into the intestinal lumen. Tacrine was rapidly taken up into the brain and demonstrated regional localization to cortex, hippocampus, thalamus, and striatum. Although the inhibition of acetylcholinesterase by tacrine is well documented, regional uptake in brain did not correlate consistently with distribution of the enzyme, supporting suggestions by others that the alleged action of tacrine in treatment of senile dementia may be by mechanisms other than cholinesterase inhibition.

Administration, Oral↗
PubMed1989

Zero-order release formulation of oxprenolol hydrochloride with swelling and erosion control.

Zero-order release of oxprenolol hydrochloride was obtained by controlling the swelling and erosion of the matrix. This formulation involves only mixing of drug, hydroxypropylmethylcellulose (HPMC), and sodium carboxymethylcellulose (Na CMC) at the ratio of 1:0.4:1.6, respectively, and compressing the mixture directly into tablets. The in vitro release pattern from this optimized matrix tablet was reproducible. Accelerated stability studies revealed that the optimized formulation remains stable for an approximately 2-year shelf life. This sustained-release (SR) tablet was evaluated in dogs, and for comparison a conventional (CV) formulation was also given at the same dose level. Plasma oxprenolol levels were monitored by a sensitive and specific high-performance liquid chromatographic (HPLC) method. Significant differences in the pharmacokinetic parameters, i.e., lower Cmax, higher values of tmax, MRT, AUC, and plasma concentration at 24 hr, and nearly constant plasma levels over 12 hr, indicated that the SR matrix tablet is superior to the CV rapid-releasing formulation. The in vitro release parameters and in vivo pharmacokinetics correlated well.

Animals↗