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61.
Decreased prefrontal 5-HT2A receptor binding in subjects at enhanced risk for schizophrenia 总被引:4,自引:0,他引:4
Hurlemann R Boy C Meyer PT Scherk H Wagner M Herzog H Coenen HH Vogeley K Falkai P Zilles K Maier W Bauer A 《Anatomy and embryology》2005,210(5-6):519-523
The brain serotonin-2A receptor (5-HT2AR) has been implicated in both the pathology of schizophrenia and the therapeutic action of atypical antipsychotics. However,
little is known about the 5-HT2AR status before the onset of schizophrenia and before the exposure to antipsychotics. We used [18F] altanserin and positron emission tomography (PET) in a pilot study of 6 individuals suspected to be at elevated risk for
schizophrenia and seven age-matched controls to test the hypothesis that regional 5-HT2AR binding is altered in the prodromal stages of schizophrenia. Distribution volume ratios (DVRs) as a proxy for 5-HT2AR availability were significantly reduced in prefrontal cortex regions of at-risk subjects, implicating early abnormalities
of serotonergic neurotransmission that antecede the onset of schizophrenia. 相似文献
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Norbert B Ghyselinck Nadège Vernet Christine Dennefeld Norbert Giese Heinz Nau Pierre Chambon Stéphane Viville Manuel Mark 《Developmental dynamics》2006,235(6):1608-1622
Using Rbp4-null mice as models, we have established for the first time the kinetics of the spermatogenetic alterations during vitamin A deficiency (VAD). Our data demonstrate that the VAD-induced testicular degeneration arises through the normal maturation of germ cells in a context of spermatogonia differentiation arrest. They indicate that retinoic acid (RA) appears dispensable for the transition of premeiotic to meiotic spermatocytes, meiosis, and spermiogenesis. They confirm that RA plays critical roles in controlling spermatogonia differentiation, spermatid adhesion to Sertoli cells, and spermiation, and suggest that the VAD-induced arrest of spermatogonia differentiation results from simultaneous blocks in RA-dependent events mediated by RA receptor gamma (RARgamma) in spermatogonia and by RARalpha in Sertoli cells. They also provide evidence that expression of major RA-metabolizing enzymes is increased in mouse Sertoli cells upon VAD and that vitamin A-deficient A spermatogonia differ from their RA-sufficient counterparts by the expression of the Stra8 gene. 相似文献
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OBJECTIVE: The objective of this study was to analyze the autonomic functions of patients with erythrophobia. METHODS: Forty patients with a diagnosis of erythrophobia (female/male ratio 18/22) without any other organic lesions and 20 healthy volunteers (female/male ratio 10/10) were assessed. Clinical evaluation was performed using a modified version of semistructured interviews. Autonomic testing was performed by means of spectral analysis of heart rate and continuous blood pressure by sparse discrete Fourier transformation at rest and under mental stress. RESULTS: There were no significant difference between the two samples in age, sex distribution, BMI, resting systolic, or diastolic blood pressure, nor was there a difference in autonomic baseline functioning between the 40 patients with erythrophobia and the control subjects. On the other hand, patients with erythrophobia consistently showed higher pulse rates (88 +/- 20 vs. 78 +/- 9 bpm, p <.05), higher total heart rate power values (8.40 +/- 0.63 vs. 8.07 +/- 1.02 p <.05), higher midfrequency spectral values (7.38 +/- 0.66 vs. 7.02 +/- 1.18, p <.01), higher high-frequency spectral values (6.89 +/- 0.86 vs. 6.48 +/- 1.44, p <.05), and lower baroreceptor sensitivity (8.62 +/- 8.16 vs. 11.65 +/- 4.42, p <.005) than the healthy subjects. ANOVA showed a significant group interaction (p <.0001) between the samples. CONCLUSIONS: This study provides evidence for abnormal autonomic functioning in patients with erythrophobia when under mental stress. 相似文献
68.
Blinded, Externally Controlled Multicenter Evaluation of Light Microscopy and PCR for Detection of Microsporidia in Stool Specimens 总被引:6,自引:4,他引:6
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Heinz Rinder Klaus Janitschke Horst Aspck Alexandre J. Da Silva Peter Deplazes Daniel P. Fedorko Caspar Franzen Ursula Futh Frank Hünger Anselm Lehmacher Christian G. Meyer Jean-Michel Molina Jrg Sandfort Rainer Weber Thomas Lscher the Diagnostic Multicenter Study Group on Microsporidia 《Journal of clinical microbiology》1998,36(6):1814-1818
The quality parameters for the detection of microsporidia in identical sets of 50 stool samples were determined for six laboratories where technicians used light microscopy and for six laboratories where technicians used PCR. The average overall sensitivities were 67% (89% for patient samples only) for the PCR laboratories and 54% (80% for patient samples only) for the light microscopy laboratories. Specificities were 98 and 95%, respectively. Differences in results were most apparent between the individual laboratories rather than between the two major methods used. 相似文献
69.
Elmar Krause Heinrich Englert Heinz Gögelein 《Pflügers Archiv : European journal of physiology》1995,429(5):625-635
Adenosine triphosphate (ATP) dependent potassium channels (KATP channels) in heart ventricular muscle cells can be activated by depletion of intracellular ATP stores as well as by channel openers. In the present study we examined whether properties of KATP channels are dependent on the mode of activation. Whole-cell and single-channel currents were investigated by use of the patch-clamp technique in isolated ventricular rat myocytes. The channel opener rilmakalim dose dependency activated whole-cell currents [concentration for half-maximal activation (EC50) = 1.1 M, Hill coefficient = 3.1, saturation concentration 10 M]. Metabolic inhibition with 2-deoxy-d-glucose (10 mmol/l) also activated KATP currents after a time lag of several minutes. These currents were about two-fold higher than the rilmakalim-activated currents (rilmakalim-activated current 3.9 ±0.2nA, 2-deoxy-d-glucose-activated current 8.1±0.9 nA; both recorded at 0 mV clamp potential). While the rilmakalim-activated current could be blocked completely and with high affinity by the sulphonylurea glibenclamide [concentration for half-maximal inhibition (IC50) = 8 nM, Hill coefficient = 0.7] the 2-deoxy-d-glucose-activated current could only be blocked partially (by maximally 46%) and higher glibenclamide concentrations were needed (IC50 = 480 nM, Hill coefficient = 0.8). The partial loss of blocking efficiency after metabolic inhibition was not restricted to glibenclamide but was also observed with the sulfonylureas glimepiride and HB 985, as well as with the non-sulfonylureas HOE 511 and 5-hydroxydecanoate. Single-channel studies were in accordance with these whole-cell experiments. Both rilmakalim and metabolic inhibition with the uncoupler carbonyl cyanide p-(trifluoromethoxy) phenylhydrazone (FCCP) activated single channels in the attached mode, where the number of current levels was significantly higher in the case of FCCP. Rilmakalim-activated channels were completely blocked by 10 M glibenclamide, whereas several single-channel levels appeared in the presence of 100 M glibenclamide after metabolic inhibition. In conclusion, after metabolic inhibition the amplitude of the activated KATP current is about twice as high as under saturating concentrations of the opener rilmakalim. Moreover, channels activated by metabolic inhibition lost part of their sensitivity to known channel blockers. 相似文献
70.
Werner M Mattis A Aubele M Cummings M Zitzelsberger H Hutzler P Höfler H 《Virchows Archiv : an international journal of pathology》1999,435(5):469-472
The 20q13 region harboring recently described putative oncogenes is frequently amplified in invasive ductal carcinoma (IDC).
The aim of this study was to examine the 20q13 copy number in intraduct hyperplasia (IH), atypical duct hyperplasia (ADH),
and ductal carcinoma in situ (DCIS) adjacent to IDC. In 5 patients, comparative genomic hybridization (CGH) after laser microdissection
revealed 20q13 amplification in four of five cases of IH, in all of three cases of IH with atypia, all five of DCIS, and all
five of IDC. Fluorescence in situ hybridization (FISH) confirmed the amplification at 20q13.2 in IH in the two specimens analyzed.
The amplification rate, however, was higher in DCIS and IDC. In phenotypically normal ductal epithelium normal values were
found for 20q13 copy number by FISH (n=2) and CGH (n=5). Although the number of cases presented here is small, our results suggest that mutations in the 20q13.2 region in IH
may be associated with accelerated proliferation and hyperplasia of the ductal epithelium. Progression to DCIS and ICD is
accompanied by a further increase in the 20q13.2 copy number.
Received: 17 March 1999 / Accepted: 22 June 1999 相似文献