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Notes: In previous studies it was reported that GaAs samples which were rapid thermal annealed exhibit bright bands adjacent to the surfaces in cathodoluminescence images of the cross sections. It is possible that the presence and depth of these bright bands are related to thermal stresses in the GaAs resulting from thermal gradients during heating and cooling. To investigate this possibility, a one-dimensional mathematical model was developed to predict the temperatures through the thickness of the GaAs. Calculations of the thermal stress field show that the thermal stresses do not correlate with the depth of the bright bands.

Notes: Maoism as a politico-religious form emerged in a society in the process of disintegration. It became crystallized as a response to the demands of rapid modernization. The Maoist belief system centers around the concept “people,” the ultimate sacred reality. Its ethic emphasizes ceaseless service to others, individual asceticism, and intensive practical activity as necessary to the achievement of social salvation and collective immortality. A number of ritual parallels are identified between Maoism and contemporary Christianity: the worship service and ministry, the initiation process, sin and atonement, and various initiative rituals. From an evolutionary perspective, both primitive and ultra-modern elements are identified in Maoism.

Notes: Abstract: Experimental animal and peripheral blood cell studies point to guanine nucleotide regulatory (G) protein disturbances in bipolar affective disorder. We have previously reported elevated prefrontal cortex Gsα protein in bipolar affective disorder and have now extended these preliminary observations in a larger number of subjects, assessing the brain regional specificity of these changes in greater detail, determining the functional biochemical correlates of such changes, and evaluating their diagnostic specificity. Membrane G protein (Gsα, Giα, Goα, and Gβ) immunoreactivities were estimated by western blotting in postmortem brain regions obtained from 10 patients with a DSMIII-R diagnosis of bipolar affective disorder and 10 nonpsychiatric controls matched on the basis of age, postmortem delay, and brain pH. To examine whether there were functional correlates to the observed elevated Gsα levels, basal and GTPγS-and forskolin-stimulated cyclic AMP production was determined in the same brain regions. Compared with controls, Gsα (52-kDa species) immunoreactivity was significantly (p 〈 0.05) elevated in prefrontal (+36%), temporal (+65%), and occipital (+96%) cortex but not in hippocampus (+28%), thalamus (-23%), or cerebellum (+21%). In contrast, no significant differences were found in the other G protein subunits (Giα, Goα, Gβ) measured in these regions. Forskolin-stimulated cyclic AMP production was significantly increased in temporal (+31%) and occipital (+96%) cortex but not in other regions. No significant differences were apparent in basal or GTPγS-stimulated cyclic AMP production. A significant correlation (r= 0.60, p 〈 0.001) was observed between forskolin-stimulated cyclic AMP formation and Gsα (52 kDa) immunoreactivity when examined across these cortical regions. The observed increase in Gsα may be specific to bipolar disorders as no significant differences were detected in Gsα levels in temporal cortex from patients with either schizophrenia (n = 7) or Alzheimer's disease (n = 7). In summary, the present study confirms and extends our earlier findings and supports the notion that increased Gsα levels and possibly Gsα-adenylyl cyclase-mediated signal transduction are relevant to the pathophysiology of bipolar affective disorder.

Notes: Abstract: The function of the phosphoinositide second messenger system was assessed in occipital, temporal, and frontal cortex obtained postmortem from subjects with bipolar affective disorder and matched controls by measuring the hydrolysis of [3H]phosphatidylinositol ([3H]PI) incubated with membrane preparations and several different stimulatory agents. Phospholipase C activity, measured in the presence of 0.1 mM Ca2+ to stimulate the enzyme, was not different in bipolar and control samples. G proteins coupled to phospholipase C were concentration-dependently activated by guanosine 5′-O-(3-thiotriphosphate) (GTPγS) and by NaF. GTPγS-stimulated [3H]PI hydrolysis was markedly lower (50%) at all tested concentrations (0.3–10 µM GTPγS) in occipital cortical membranes from bipolar compared with control subjects. Responses to GTPγS in temporal and frontal cortical membranes were similar in bipolars and controls, as were responses to NaF in all three regions. Brain lithium concentrations correlated directly with GTPγS-stimulated [3H]PI hydrolysis in bipolar occipital, but not temporal or frontal, cortex. Carbachol, histamine, trans-1-aminocyclopentyl-1,3-dicarboxylic acid, serotonin, and ATP each activated [3H]PI hydrolysis above that obtained with GTPγS alone, and these responses were similar in bipolars and controls except for deficits in the responses to carbachol and serotonin in the occipital cortex, which were equivalent to the deficit detected with GTPγS alone. Thus, among the three cortical regions examined there was a selective impairment in G protein-stimulated [3H]PI hydrolysis in occipital cortical membranes from bipolar compared with control subjects. These results directly demonstrate decreased activity of the phosphoinositide signal transduction system in specific brain regions in bipolar affective disorder.

Notes: Abstract: Although guanine nucleotide binding proteins (G proteins) are one of the critical components of signal transduction units for various membrane receptor-mediated responses, little information is available regarding their status in brain of patients with neurodegenerative illnesses. We measured the immunoreactivity of G protein subunits (Gsα, Giα, Goα, Gq/11α, and Gβ) in autopsied cerebellar and cerebral cortices of 10 end-stage patients with dominantly inherited olivopontocerebellar atrophy (OPCA) who all had severe loss of Purkinje cell neurons and climbing fiber afferents in cerebellar cortex. Compared with the controls, the long-form Gsα (52-kDa species) immunoreactivity was significantly elevated by 52% (p 〈 0.01) in the cerebellar cortex of the OPCA patients, whereas the Gi1α concentration was reduced by 35% (p 〈 0.02). No statistically significant differences were observed for Goα, Gi2α, Gβ1, Gβ2, or Gq/11α in cerebellar cortex or for any G protein subunit in the two examined cerebral cortical subdivisions (frontal and occipital). The cerebellar Gsα elevation could represent a compensatory response (e.g., sprouting, reactive synaptogenesis) by the remaining cerebellar neurons (granule cells?) to neuronal damage but also might contribute to the degenerative process, as suggested by the ability of Gsα, in some experimental preparations, to promote calcium flux. Further studies will be required to determine the actual functional consequences of the G protein changes in OPCA and whether the elevated Gsα is specific to OPCA cerebellum, because of its unique cellular pattern of morphological damage, or is found in brain of patients with other progressive neurodegenerative disorders.

Notes: Objective— To observe in serial fashion the histological changes of human papilloma virus (HPV) infection of the cervix and to correlate these with the detection of HPV genomes.Design— A prospective longitudinal study to perform colposcopy and at 0,9 and 18 months to obtain a smear, a biopsy for histology and HPV-16 genome detection by DNA/DNA hybridization.Setting— Glasgow Family Planning Centre.Subjects— Eighty-two women recruited on the basis of a routine smear showing viral change without dyskaryosis.Interventions— Women found to have CIN 3 were treated with laser.Main outcome measures— Cytology and cervical biopsy results and HPV-16 DNA detection by Southern blotting obtained serially from individual subjects.Results— Of 82 women recruited, 10% were positive for HPV-16 detection by Southern blotting. Detection of HPV-16 genomes did not correlate with either CIN or viral infection assessed histologically and serial hybridizations in a given individual showed fluctuation in HPV-16 detection. Polymerase chain reaction in a subset of samples revealed 46% positive for HPV DNA.Conclusion— No clear correlation exists between HPV genome detection and the histological appearance. HPV-16 genome detection alone may not be a useful predictor of precancerous progression.