Denaturing gradient gel electrophoresis: a novel method for determining Rh phenotype from genomic DNA

Denaturing gradient gel electrophoresis (DGGE) was carried out on PCR products amplified from exons 2 and 5 of RHD and RHCE. Exon 2 of RHD and exon 2 of the C allele of RHCE have an identical sequence, which differs from that of the c allele of RHCE. One band representing D and/or C, and another representing c, could be distinguished by DGGE of exon 2 amplifications of genomic DNA from individuals with the appropriate Rh phenotype. C and c could only be distinguished in D-negative samples. Exon 5 of RHD and exon 5 of the E and e alleles of RHCE all have different nucleotide sequences. Bands representing D, E and e could be distinguished following DGGE of the products of exon 5 amplification of genomic DNA from individuals with red cells of the appropriate Rh phenotype. In samples from individuals with VS+ red cells (V+ or V?) there was a shift of the band representing e. Sequencing demonstrated that VS is associated with a RHCE e sequence with a single base change predicting a Leu245 → Val substitution in the Rh polypeptide. This substitution may be responsible for the VS and e^s antigens.     

Weight change affects serum leptin and corticosterone in the collared lemming

The aim of this study was to determine whether photoperiod-induced changes in body and fat mass are accompanied by changes in leptin and corticosterone concentrations in collared lemmings. At weaning, eighty male lemmings were maintained in either long photoperiod (LD, n = 40 ) or short photoperiod (SD, n = 40 ). Ten weeks post-weaning lemmings were weighed and assigned to a secondary photoperiod that consisted of either remaining in the same photoperiod or being transferred to the alternate photoperiod (LD-LD, LD-SD, SD-SD, and SD-LD; n = 20 per group). Ten days post-switch, half the animals from each group were sacrificed. The remaining animals were sacrificed on day 21 post-switch. Blood was collected for determination of serum leptin and corticosterone, and carcasses were analyzed for body composition. LD-SD lemmings gained the most weight, whilst SD-LD lemmings lost weight. SD-LD lemmings had significantly lower leptin levels relative to fat mass than SD-SD lemmings. Corticosterone levels were higher in the SD-LD than SD-SD lemmings on both days 10 and 21. Levels were not significantly different between LD-LD and LD-SD lemmings; however by day 21 the levels were slightly lower in the LD-SD lemmings. Discussion. Lemmings showed seasonally appropriate body weight changes in response to the changing photoperiod. Weight loss was associated with higher corticosterone, and lower leptin levels adjusted for fat mass. Neither relative leptin levels, nor corticosterone levels changed significantly with weight gain. Our results indicate that corticosterone and leptin are associated more with seasonal weight loss than weight gain in lemmings.     

Oscillatory brain states and learning: Impact of hippocampal theta-contingent training

Eyeblink classical conditioning is a relatively simple form of associative learning that has become an invaluable tool in our understanding of the neural mechanisms of learning. When studying rabbits in this paradigm, we observed a dramatic modification of learning rate by conducting training during episodes of either hippocampal theta or hippocampal non-theta activity as determined by on-line slow-wave spectral analysis. Specifically, if animals were given trials only when a computer analysis verified a predominance of slow-wave oscillations at theta frequencies (3-8 Hz), they learned in half as many trials as animals trained during non-theta hippocampal activity (58 vs. 115). This finding provides important evidence from awake, behaving animals that supports recent advances in our knowledge of (i) brain sites and neurobiological mechanisms of learning and memory, specifically hippocampus and theta oscillations, (ii) the biological plausibility of current models of hippocampal function that posit important roles for oscillatory potentials, and (iii) the design of interfaces between biological and cybernetic (electronic) systems that can optimize cognitive processes and performance.     

Long-term results of stereotactic radiosurgery to the pituitary gland in Cushing's disease

Gamma radiation from 60Co delivered with stereotactic technique was given to the pituitary gland in 35 patients, aged 18-65 years, with Cushing's disease. The doses were 70-100 Gy in each single irradiation. The size of the sella turcica was normal in the majority of the patients. The observation time was 3-9 years in 29 patients. Out of them, 14 (48%) obtained clinical remission and normal urinary cortisol after one irradiation. Eight achieved remission after two to four irradiations. In total, 22 out of 29 patients (76%) obtained remission. In 12 of them remission was obtained in 1 year and in another 10 within 3 years. No recurrences were observed. Improvement was seen in 2 patients after one and three irradiations. Bilateral adrenalectomy was performed in 5 patients owing to unsatisfactory effect of irradiation. Pituitary insufficiency with gonadotropin, thyrotropin or corticotropin failure was demonstrated in 12 of 22 patients in remission. This occurred 4 months to 7 years after the first irradiation. Another 6 patients were followed less than 3 years after the first irradiation. Two obtained remission after the first treatment, whereas the other 4 improved. Stereotactic pituitary irradiation is suggested as a non-invasive therapeutic alternative in Cushing's disease for example in patients with considerable surgical risk or as a supplement to pituitary microsurgery.     

Hepatic expression of interferon-α in chronic hepatitis B virus infection

Hepatic expression of interferon- (IFN-) was examined by immunohistochemistry in 90 Chinese patients (M/F 67:23, age: 14–69) with a spectrum of hepatitis B virus (HBV)-related chronic liver diseases. Immunoreactive IFN- was detected in sinusoidal cells in 79 patients (88%) and in mononuclear cells in 59 patients (65.6%). Patients with active liver diseases (chronic active hepatitis, active cirrhosis,N=55) had a higher level of IFN- expression compared to patients with inactive histology (N=35; sinusoidal cells,P<0.01; mononuclear cells,P<0.01). Cytoplasmic HBsAg, nuclear HBcAg, and cytoplasmic HBcAg were detected in 79 (88%), 42 (47%), and 23 (27%) patients respectively. Expression of IFN- in mononuclear cells correlated with the expression of cytoplasmic HBcAg (P<0.05) but not with nuclear HBcAg or cytoplasmic HBsAg. When the patients were divided into four different phases according to the natural history of chronic HBV infection, patients in the active liver disease phase had higher IFN- expression compared to the immunotolerant and late phase patients (P<0.01). Using double immunohistochemical staining, both IFN- and cytoplasmic HBcAg were frequently detected near inflammatory infiltrates but no correlation existed between the hepatic expression of HBsAg and IFN-. These data indicate that IFN- is expressed in the liver in HBV-related active liver diseases and that the reported suboptimal production of IFN- by PBMC in HBV-related chronic active liver diseases may be due to a redistribution of the IFN--producing mononuclear cells into the liver, the site of inflammation.     

Indicators of Genetic and Environmental Influence in Alcohol-Dependent Individuals

Although much is known about genetic and environmental influences in alcohol dependence at the population level, little is known about the relative contribution of such influences on individuals. As an initial step toward individual assessment, concordance for the Diagnostic Interview Schedule, version III alcohol symptoms was determined in a sample ( n = 113) of male monozygotic (MZ) and dizygotic (DZ) twins. Items were assigned to a genetic or environmental scale on the basis of significant MZ/DZ differences in proband-wise concordance rates. Weights were assigned to items based on factor analyses. For the genetic scale, significant differences were found between MZ and DZ intraclass correlations. No significant differences were found between MZ and OZ correlations on the environmental scale. When scores on the environmental scale were controlled, genetic scale scores were correlated with earlier age of onset of alcohol problems and a shorter interval between first intoxication and onset of alcohol problems. When scores on the genetic scale were controlled, environmental scale scores were correlated with later age of onset of alcohol problems and a longer interval between first intoxication and onset of alcohol problems. These results suggest it is possible to assess relative influence of genetic and environmental factors in individual cases of alcohol dependence.     

Effect of bivalirudin on length of stay in the recovery area after percutaneous coronary intervention compared with heparin alone, heparin + abciximab, or heparin + eptifibatide

Three hundred nine patients were followed during their recovery area stay after percutaneous coronary intervention. Recovery area times for patients who received bivalirudin during percutaneous coronary intervention showed an average reduction in total recovery area length of stay of 36 minutes (p <0.0001) compared with patients who received heparin alone. This reduction was also seen when compared with the heparin + abciximab group (46-minute reduction, p = 0.0007), and the heparin + eptifibatide group (35-minute reduction, p = 0.0005). Patients who received bivalirudin took significantly less time for the activated clotting time (ACT) to normalize despite significantly higher average ACTs and significantly fewer subtherapeutic ACTs.