Venous blood arterialization and parameters from the minimal models of glucose disappearance and post-hepatic insulin delivery

A dot-blot hybridisation assay using high molecular weight DNA as whole chromosomal probes was used to differentiate Bacteroides tectum from Bacteroides fragilis. 32P-labelled probes were compared with digoxigenin (DIG)-labelled probes. The whole chromosomal probes were specific--differentiating B. tectum from B. fragilis and both from a variety of other species (including other members of the genera Bacteroides, Fusobacterium, Eubacterium, and Prevotella) found in normal and abnormal mouths of cats and horses. However, even at very high stringencies, B. tectum homology groups I, II and III were not distinguishable from one another using either 32P-labelled or DIG-labelled probes. Thus, DIG-labelled whole chromosome probes directed against cellular DNA released directly onto nitrocellulose membranes is considered a useful method for diagnostic veterinary laboratories wishing to identify B. tectum and distinguish it from B. fragilis and other oral anaerobic flora of cats.     

Reassessment of glucose effectiveness and insulin sensitivity from minimal model analysis: a theoretical evaluation of the single-compartment glucose distribution assumption

Minimal model analysis with the frequently sampled intravenous glucose tolerance test provides an effective way to measure two important metabolic parameters in vivo under non-steady-state conditions: glucose effectiveness (SG) and insulin sensitivity (SI). Two questions regarding the validity of SG and SI have recently emerged. First, SG from the minimal model is suspected to be overestimated. Second, the occurrence of SI values indistinguishable from zero ("zero-SI") is not negligible in large clinical studies, and its physiological meaning is uncertain. In this study, we examined the significance of the assumed single-compartment glucose distribution embedded in the minimal model on the estimation of SG and SI. A more accurate two-compartment model was constructed by incorporating insulin action on hepatic glucose output and uptake into a previously validated construction. The two-compartment results were compared with the one-compartment minimal model results. It was shown that the one-compartment assumption contributes to a systematic deviation of SG (slope = 0.54, y-intercept = 0.014 min[-1]; n = 195 simulations). However, SG from the minimal model was linearly correlated to SG determined from the two-compartment model (r = 0.996). The one-compartment assumption also contributed to the occurrence of zero SI values for insulin-resistant subjects. A similar linear relationship was found between SI estimated by both the minimal model and the two-compartment model (slope = 0.58, y-intercept = -0.57 x 10[-4] min[-1] per pU/ml, r = 0.998). In conclusion, SG and SI from the minimal model are not necessarily equivalent to values emanating from the more accurate two-compartment model. However, the very high correlation between one- and two-compartment results suggests that the minimal model-derived SG and SI are dependable indexes of in vivo glucose effectiveness and insulin sensitivity. Minimal model analysis' advantages of simplicity, minimal invasiveness, reasonable reflection of non-steady-state glucose kinetics, and cost-effectiveness could in many cases outweigh the structural bias introduced by the model simplification.     

Contingency model of leadership effectiveness: Some experimental results.

Conducted 2 parallel experiments with 78 and 96 undergraduates to replicate and further study the contingency model of leadership effectiveness proposed by F. Fiedler. Ss were assigned to 3-man groups and completed a high and a low structured task after selecting a leader. Ss completed a measure of leadership style, the Least Preferred Co-worker (LPC) scale, a group atmosphere scale, and a leader behavior scale. None of the observed correlations for either study reached significance, and in Exp. II, only 2 of the 7 correlations were in the hypothesized direction. Results along with those of other studies are discussed as casting doubt on the plausibility of the contingency model. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Vacuum evaporation of KCl-NaCl salts: Part II. vaporization-rate model and experimental results

A model based on the Hertz-Langmuir relation is used to describe how evaporation rates of the binary KCl-NaCl system change with time. The effective evaporation coefficient (α), which is a ratio of the actual evaporation rate to the theoretical maximum, was obtained for the KCl-NaCl system using this model. In the temperature range of 640 °C to 760 °C, the effective evaporation coefficient ranges from ～0.4 to 0.1 for evaporation experiments conducted at 0.13 Pa. At temperatures below the melting point, the lower evaporation coefficients are suggested to result from the more complex path that a molecule needs to follow before escaping to the gas phase. At the higher liquid temperatures, the decreasing evaporation coefficients result from a combination of the increasing vaporflow resistances and the heat-transfer effects at the evaporation surface and the condensate layer. The microanalysis of the condensate verified that composition of the condensate changes with time, consistent with the model calculation. The microstructural examination revealed that the vaporate may have condensed as a single solution phase, which upon cooling forms fine lamellar structures of the equilibrium KCl and NaCl phases. In conclusion, the optimum design of the evaporation process and equipment must take the mass and heat transfer factors and equipment materials issues into consideration.     

Linkage and association between a CD4 gene polymorphism and IDDM in Danish IDDM patients. The Danish IDDM Epidemiology and Genetics Group, and The Danish Study Group of Diabetes in Childhood

PURPOSE: Our purpose was to determine the neuroradiologic findings of Marinesco-Sj?gren syndrome on plain skull radiographs, CT, and MR images. METHODS: Eight patients with proved Marinesco-Sj?gren syndrome (age range, 4 to 56 years) had a total of nine CT scans, seven MR imaging studies, and two plain radiographic examinations of the skull. The findings were reviewed retrospectively, with particular attention to the size of the posterior fossa and cerebellum. RESULTS: All patients had hypoplastic cerebellar hemispheres and a hypoplastic vermis in a small posterior fossa. One patient had a midline posterior fossa cyst and another had agenesis of the corpus callosum. CONCLUSION: Hypoplasia of the cerebellar hemispheres and the vermis and a small posterior fossa are the most prominent neuroradiologic findings in Marinesco-Sj?gren syndrome.     

Mechanism of glucose intolerance during fasting: differences between lean and obese subjects

Oral glucose tolerance tests were performed on 14 lean and 14 obese nondiabetic subjects before and after a 6-day fast. In addition, insulin tolerance tests were performed on 8 lean and 8 obese subjects before and after starvation. Both in lean and obese subjects glucose tolerance deteriorated during starvation, but much more so in the lean population. During fasting, insulin elevation after a glucose load was significantly delayed in lean subjects but not in the obese. Circulating levels of factors known to affect glucose tolerance, such as glucagon, growth hormone, free fatty acids, and ketone bodies were higher in fasting lean than in fasting obese individuals. In normals fasting resulted in a significant decrease of the blood glucose response to insulin injection, whereas in fasting obese subjects glucose response was unchanged. The results obtained suggest that the effect of fasting on insulin release and insulin sensitivity was more pronounced in lean than in obese subjects, which resulted in greater deterioration of glucose tolerance in the lean population.     

Selective brain dopamine depletion in developing rats: an experimental model of minimal brain dysfunction

Administration of 6-hydroxydopamine to neonatal rats produces a rapid and profound depletion of brain dopamine. Total activity of treated animals is significantly greater than that of controls between 12 and 22 days of age, but then declines, an activity pattern similar to that seen in affected children. This suggests a functional deficiency of brain dopamine in the pathogenesis of minimal brain dysfunction.     

Differing effects of pancreas-kidney transplantation with systemic versus portal venous drainage on cholesteryl ester transfer in IDDM subjects

OBJECTIVE: Cholesteryl ester transfer (CET) is accelerated in patients with IDDM treated with conventional (subcutaneous) insulin therapy (CIT) and a number of other disorders associated with premature cardiovascular disease. We have shown that in IDDM this disturbance is closely linked to iatrogenic hyperinsulinemia (HI), because it was reversed when insulin was administered by the intraportal (i.p.) route. In this study, we sought to determine whether HI after successful pancreas-kidney transplantation (PKT) has the same adverse effect on CET. RESEARCH DESIGN AND METHODS: CET was measured by both mass and isotopic assays and compared in two groups of euglycemic non-insulin-requiring IDDM PKT patients with either systemically draining allografts and persistent HI or grafts with portal vein anastomoses that were normoinsulinemic (PK-P). A third group of eight nondiabetic kidney transplant (KT) patients receiving the same immunosuppressive drugs served as control subjects. RESULTS: CET in pancreas-kidney transplantation subjects with systemic venous drainage (PK-S) was increased (P < 0.001) to the same level we have reported previously in IDDM patients receiving CIT and was significantly higher (P < 0.001) than in those subjects with PK-P. CET in the PK-P group did not differ from that of the KT control patients. CONCLUSIONS: CET is affected by variations in systemic insulin levels in pancreas transplant patients with allografts that have differing venous drainage. Because high systemic insulin levels are linked to the activation of (ET, euglycemic HI IDDM pancreas allograft recipients may continue to be at high risk for macrovascular complications.     

Microvascular anastomosis with minimal suture and fibrin glue: experimental and clinical study

A 24-year-old man infected with human immunodeficiency virus type I rapidly progressed to acquired immune deficiency syndrome. His clinical picture was compatible with a presumptive diagnosis of cerebral toxoplasmosis. Application of a nested polymerase chain reaction (PCR) succeeded in detecting Toxoplasma gondii DNA in both the venous blood and cerebrospinal fluid specimens. This result indicates that PCR is a convenient tool for making a rapid and accurate diagnosis of cerebral toxoplasmosis, especially in developing countries.     

Ketosis-onset diabetes in young adults with subsequent non-insulin-dependency, a link between IDDM and NIDDM?

Reactivation of infections with herpes viruses is a frequent and major cause of morbidity after bone marrow transplantation. In this case report we stress that HSV infections of the colon and small intestine should be considered in the differential diagnosis of diarrhea and intestinal bleeding in the early post-transplantation period. Severe acute GVHD and subsequent intensive immunosuppressive treatment may increase the risk for reactivation of HSV infection particularly in situations in which acyclovir prophylaxis has been omitted.     

Dangers in applying results from experimental social psychology.

Suggests that the application of the results of much social psychological research tends to (a) support and reinforce those aspects of the "real" world that promote such activities as unilateral control over others, manipulation, conformity, deception, and self-sealing processes; and (b) support the status quo. The basic causes are hypothesized to be related to the norm that the task of social science is to describe reality and to the requirements inherent in maximizing the internal validity of experiments. (29 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Treatment with the oral antidiabetic agent troglitazone improves beta cell responses to glucose in subjects with impaired glucose tolerance

Impaired glucose tolerance (IGT) is associated with defects in both insulin secretion and action and carries a high risk for conversion to non-insulin-dependent diabetes mellitus (NIDDM). Troglitazone, an insulin sensitizing agent, reduces glucose concentrations in subjects with NIDDM and IGT but is not known to affect insulin secretion. We sought to determine the role of beta cell function in mediating improved glucose tolerance. Obese subjects with IGT received 12 wk of either 400 mg daily of troglitazone (n = 14) or placebo (n = 7) in a randomized, double-blind design. Study measures at baseline and after treatment were glucose and insulin responses to a 75-g oral glucose tolerance test, insulin sensitivity index (SI) assessed by a frequently sampled intravenous glucose tolerance test, insulin secretion rates during a graded glucose infusion, and beta cell glucose-sensing ability during an oscillatory glucose infusion. Troglitazone reduced integrated glucose and insulin responses to oral glucose by 10% (P = 0.03) and 39% (P = 0.003), respectively. SI increased from 1.3+/-0.3 to 2.6+/-0.4 x 10(-)5min-1pM-1 (P = 0.005). Average insulin secretion rates adjusted for SI over the glucose interval 5-11 mmol/liter were increased by 52% (P = 0.02), and the ability of the beta cell to entrain to an exogenous oscillatory glucose infusion, as evaluated by analysis of spectral power, was improved by 49% (P = 0.04). No significant changes in these parameters were demonstrated in the placebo group. In addition to increasing insulin sensitivity, we demonstrate that troglitazone improves the reduced beta cell response to glucose characteristic of subjects with IGT. This appears to be an important factor in the observed improvement in glucose tolerance.     

Relations between personality and smoking behavior in preadult subjects.

Results from 562 high school and junior high school students cross-validated and extended the generality of earlier work with 1462 adults. In both studies, smoking status, on the basis of self-report information, and personality scores derived from peer ratings, showed smokers significantly (p     

Suggestibility in hypochondriacal patients and healthy control subjects. An experimental case-control study

The effects of slow freezing and thawing on enzyme compartmentalization and ultrastructure were studied in rat liver slices frozen in dry ice, isopentane/ethanol-dry ice, or liquid nitrogen, and stored at -80 degrees C for 1-14 days. Non-frozen slices served as controls. Frozen liver slices were thawed in a Karnovsky fixative and processed for transmission electron microscopy (TEM). After all freezing protocols, the outer zone of frozen-thawed tissue was ultrastructurally very similar to that of non-frozen liver. Towards the center of the tissue, the ultrastructure progressively deteriorated. Comparison with 50-microm cryostat sections prepared for TEM showed that thawing and not freezing is the detrimental step for fair preservation of ultrastructure. After thawing, homogenization, and differential centrifugation, distribution patterns of soluble marker enzymes were analyzed (cytosol, lactate dehydrogenase; mitochondrial matrix, glutamate dehydrogenase; lysosomes, acid phosphatase). The enzyme activities were not affected by storage for 2 weeks and the activity distributions showed that protein leakage from compartments was only minimally increased in frozen-thawed tissue compared with that from non-frozen tissue, irrespective of the method of freezing. In conclusion, fairly large tissue slices (20x5x3 mm) may be frozen and stored at -80 degrees C for biochemical, ultrahistochemical or ultrastructural studies. For ultrastructural analysis, only the periphery of the tissue slice should be used.     

WAIS factor analysis with brain-damaged subjects using criterion measures.

Correlated the assessment of brain damage vs. no brain damage and of right vs. left brain damage with factors and individual subtest results obtained from a factor analysis of the WAIS. Corresponding groups of 103 hospitalized patients were used. Results demonstrate that the WAIS was affected by brain damage although its factor structure was not. The general scores in each factor were reduced while the structure of the general, verbal, performance, and memory factors was not greatly changed from normal WAIS factors. All subtests, especially Digit Symbol, were affected but not in accordance with Wechsler's Deterioration Index. Laterality of brain damage was not related to verbal and performance factors in chronic brain damage although the Digit Span was significantly more impaired by left-hemisphere damage. (26 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)