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Biomedical subjects

B Beck

Publications and source records attributed to B Beck.

229 records · Page 13Linked to original sources
PubMedDate not supplied

A temperature-dependent quantum mechanical/neural net model for vapor pressure.

We present a temperature-dependent model for vapor pressure based on a feed-forward neural net and descriptors calculated using AM1 semiempirical MO-theory. This model is based on a set of 7681 measurements at various temperatures performed on 2349 molecules. We employ a 10-fold cross-validation scheme that allows us to estimate errors for individual predictions. For the training set we find a standard deviation of the error s = 0.322 and a correlation coefficient (R(2)) of 0.976. The corresponding values for the validation set are s = 0.326 and R(2) = 0.976. We thoroughly investigate the temperature-dependence of our predictions to ensure that our model behaves in a physically reasonable manner. As a further test of temperature-dependence, we also examine the accuracy of our vapor pressure model in predicting the related physical properties, the boiling point, and the enthalpy of vaporization.

Journal Article↗
PubMedDate not supplied

Normalization of lipid metabolism after withdrawal from antihypertensive long-term therapy with beta blockers and diuretics.

Blood pressure and serum lipoprotein concentrations were assessed in 40 men with essential hypertension at the end of a long-term, controlled intervention study (HAPPHY) after 5.2 +/- 1.4 years of treatment with hydrochlorothiazide (n = 23) or atenolol (n = 17) and after a wash-out period. After withdrawal from antihypertensive medication, the blood pressures of patients treated with diuretics or beta blockers rose from 142/93 and 145/91 to 159/106 and 165/104 mm Hg, respectively. At the same time, low density lipoprotein cholesterol decreased by 17 and 12 mg/dl, respectively, in the diuretic and beta blocker groups (p less than 0.05). In addition, total cholesterol decreased by 16 mg/dl (p less than 0.05) in the diuretic group, whereas high density lipoprotein cholesterol increased by 8 mg/dl (p less than 0.01) and triglycerides decreased by 27 mg/dl (p less than 0.05) in the beta blocker group at the end of the wash-out period as compared to the final phase of the HAPPHY study. The data indicate the persistence of lipid changes during long-term treatment with hydrochlorothiazide and atenolol. For the first time, it was clearly demonstrated that the well-known unfavorable effects of diuretics and beta blockers on lipid metabolism are reversible after cessation of long-term therapy of several years' duration.

Antihypertensive Agents↗
PubMedDate not supplied

Effect of exchange of ham for boiled egg on plasma glucose and insulin responses to breakfast in normal subjects.

Blood glucose (BG) and plasma insulin (IRI) were measured during two breakfasts different only by the nature of proteins--egg (E) or ham (H)--in eight normal subjects. Compared with H, E led to a flattened BG response at 30, 40, and 50 min and to a sustained BG from 150 to 240 min. Integrated BG response was not significantly different between E and H. After E, the IRI response decreased at 90 min and 120 min (P less than 0.05). Integrated IRI response with E was significantly smaller than with H (P less than 0.025). The reasons for the effect of E ingestion on BG are not obvious; pancreatic and/or intestinal mechanisms may be involved. It is suggested that greater consideration be given to the protein composition of the test meals when they are used in studies of glucose homeostasis.

Adult↗
PubMedDate not supplied

[Vulvar lesion in urogenital schistosomiasis (S. haematobium)].

Genital schistosomiasis must be considered in women from endemic areas presenting with the following signs and symptoms: Vulvar papules, swelling or tumour irregular vaginal bleeding infertility, ectopic pregnancy Urinary tract schistosomiasis can affect the lower and upper female genital tract.

Adult↗
PubMedDate not supplied

The changes of alpha-amylase activity in serum and different tissues of female rat during sex cycle--isoelectrofocusing studies of alpha-amylase.

BACKGROUND: It has been suggested that hormonal changes may influence alpha-amylase activity during sex cycle. The aim of this study was to evaluate these changes in serum and different tissues during sex cycle in female rats. MATERIAL AND METHODS: The animals were assigned to proestrus, estrus, and diestrus groups depending on vaginal smears. We measured the activities of alpha-amylase in the serum, liver, salivary glands, pancreas and ovary of female rats, serum level of calcium, rat luteinising hormone (rLH) and rat follicle stimulating hormone (rFSH). The serum and tissue amylases were also characterized by wide-range polyacrylamide gel isoelectrofocusing. RESULTS: Statistically significant changes of alpha-amylase activity were found only in the ovary. The activity of alpha-amylase raised from proestrus (mean 303 +/- 124 IU/g) through estrus (mean 157 +/- 123 IU/g) and declined in diestrus (mean 81.9 +/- 51.6 IU/g). There were no statistically significant changes in the serum, liver, salivary glands and pancreas. We found two isoenzymes of alpha-amylase: one peak of amylase, present in the serum, liver, salivary gland and ovary with the mean isoelectric point of ca 5.34 and another present in ovary and pancreas with mean isoelectric point of ca 8.32. The only tissue found to contain both isoamylases was the ovary. We did not find any correlation between serum calcium level and alpha-amylase activity in the serum and ovary. CONCLUSION: The pattern of changes of alpha-amylase activity does not depend on the type of isoamylase in the tissue, but probably on the tissue influenced by the sex cycle. The changes of alpha-amylase activity are not mediated by calcium, they seem to result primarily from the profile of sex hormones affecting directly the target tissues.

Animals↗
PubMedDate not supplied

[Plasma insulin and glucagon after ingestion of meal enriched with increased doses of pectin in healthy man].

The effects of three doses of pectin (5, 10 and 15 g) included in a solid-liquid meal on the postprandial plasma insulin and glucagon responses were studied in 12 healthy men. The mean plasma glucagon level was significantly smaller with 5 g of pectin than the control values at 150 min (p less than 0.05) whereas plasma insulin values did not vary. No change in mean plasma glucagon and insulin levels was noted with 10 g and 15 g of pectin although the mean blood glucose levels were significantly higher than the control values at 180 min (p less than 0.05). Addition of pectin to a meal, even if the doses were relatively important, had little or no effect on the postprandial hormonal responses in healthy men. However, pectin could be of renewed interest because of the possibility of its action of satiety by means of sustained late blood glucose levels.

Adult↗
PubMedDate not supplied

[Specific delays of language development in special education students].

The frequencies of specific language retardation and deficits in short term memory span are the subject of this epidemiological investigation of children attending the first grade of a special school for educationally subnormal children in Erlangen and München/Rosenheim. The children at the mean age of seven were examined according to the "Multi-axial Classification of Child Psychiatric Disorders". The following prevalences were found: 16 children (21%) of the sample from Erlangen and 24 children (33%) of the sample from München/Rosenheim had an specific language retardation, in both sample the most frequent disorders were retardations of the expressive language (11% and 21%). In both sample most children had substantially deficits in the acoustic short term memory span, while they were better on visual short term memory span. Significant correlations between acoustic short term memory span and specific language retardations were found.

Articulation Disorders↗
PubMedDate not supplied

[Psychomotor delay and psychiatric diagnoses in special education students].

76 first grade children of a special school for learning disabled were tested for specific developmental disorders of motor functions (SDDM). 15 children (19.7%), boys and girls proportionately, had a SDDM. This is a substantial increase compared to the unselected population. 8 children (15.5%) suffered from a specific disorder of body coordination and low finger-eye coordination. 4 children (5.3%) were found to have specific disorders of motor functions and specific language retardations. Isolated disorders of hand coordination were not found. 31% of the children with SDDM suffered from psychiatric disorders. Roughly the same percentage of psychiatric diagnosis was found in children without disorders of motor functions. A total of 24 children (33%) had impaired physical coordination: these children had significantly higher total scores in the Child Behavior Checklist (CBCL). Though this questionnaire was not sensitive for detection of disorders of motor functions.

Child↗
PubMedDate not supplied

[Intelligence and language performance of special education children at 7 and 9 years of age].

Prospective longitudinal data from children at a school for learning disabled were obtained. Intelligence and language scores were assessed at first grade and two years later. The results of two samples from Erlangen and München showed a high stability of the intelligence scores but less stability of the language scores. There were remarkable improvements in language comprehension. Expressive language had a constant lag compared with the test-standard of children of the same age; the articulation did improve as expected. The children from this special school still had problems with verbal short term memory.

Child↗
PubMedDate not supplied

Origin of serum alpha-amylase isoenzymes from healthy adult rats.

In connection with common use of rats in experimental testing drug toxicity in the liver or pancreas, we checked the electrophoretic patterns of amylase isoenzymes extracted from the liver, pancreas, parotis and serum of healthy adult rats. Separation of isoenzymes was made by polyacrylamide gel electrophoresis. The results indicate the salivary glands and liver as sources of serum alpha-amylase.

Animals↗