A qualitative and quantitative analysis of the entorhinal cortex in schizophrenia

The entorhinal cortex (ERC) has been implicated in schizophrenia by a number of studies. There is anatomical observation of neuronal heterotopias in the rostral ERC, which is consistent with a hypothesis of neurodevelopmental abnormalities in this disease. In view of the significant cytoarchitectonic variation of the ERC throughout its rostro-caudal extent, we performed a detailed subareal analysis of the rostral two-thirds of the entorhinal cortex (ERCr) in 14 postmortem schizophrenic brains and 14 matched controls (mean ages of 48 and 47 respectively). This systematic evaluation included both a qualitative microscopic analysis of morphogenetic anomalies that would be consistent with neurodevelopmental pathology and quantitative measurements of total neuronal number, average neuronal density, laminar volume and laminar depth from the cortical surface in cytoarchitectonically matched subareas of schizophrenic and control brains. Parcellation of the entire ERC on the basis of cytoarchitectonic criteria identified five distinct regions, similar to those described in the macaque, except that in the human brain three of the regions were further divisible into two or three subareas, yielding nine distinct cellular compartments. Five rostral areas, prorhinal (Pr), lateral (28L), intermediate rostral and caudal (281r and 281c), and sulcal (28S), comprise the ERCr. Gross and microscopic examination of these subdivisions throughout the ERCr failed to reveal laminar disorganization in any of the schizophrenic brains. The brains also did not differ significantly with respect to total neuronal number, total volume and neuronal density per laminar and subareal subdivision, or laminar thickness per entorhinal subarea. However, neuronal number and density were reduced by 12-18% in Pr and 28L, suggesting that mild quantitative abnormalities may exist in the ERCr and might possibly be revealed in a larger sample of schizophrenic brains. We have failed to confirm previous reports of laminar disorganization in the ERCr in brains of patients with schizophrenia; to the extent that this region is implicated in schizophrenia, the structural changes are likely to consist of more subtle cellular disturbances.      

Evidence for gene silencing by DNA methylation in normal human diploid fibroblasts

Human diploid fibroblasts, strain MRC-5, were permeabilized by electroporation and treated with 5-methyl deoxycytidine triphosphate (5-methyl dCTP) in the S phase of the cell cycle. The frequency of TG^RHPRT^– cells was increased up to 20-fold in comparison to control untreated cultures. Representative TG^R clones were unable to grow in HAT, and these were treated with 5-azacytidine (5-aza-CR). In many cases subsequent growth in HAT medium was observed, but in others it is likely that the cells had run out of growth potential. The results provide the first evidence of the silencing and reactivation of a gene in normal diploid mammalian cells.     

Clinically unsuspected venous malformations limited to the submandibular triangle: CT findings.

PURPOSETo present the CT characteristics of histologically confirmed venous vascular malformations limited to the submandibular triangle in patients without clinical stigmata of venous vascular malformations.METHODSThe clinical records and CT scans of five women with venous vascular malformations limited to the submandibular triangle were reviewed. Patients ranged from 39 to 70 years of age. None of the patients had a history of malignant tumors. All patients presented with a solitary suprahyoid neck mass. None of the patients demonstrated cutaneous manifestations of venous vascular malformation.RESULTSContrast-enhanced CT scans in all five patients demonstrated a lobulated, heterogeneously enhancing, well-circumscribed solid mass, separable from the submandibular gland. Areas of contrast enhancement within each mass were isodense to the internal jugular vein in four of five cases. Only two of five lesions demonstrated focal calcifications. Excisional biopsy (two patients) demonstrated pathologic features compatible with venous vascular malformation. Fine needle aspirations (three patients) yielded venous blood or blood-tinged fluid.CONCLUSIONSVenous vascular malformations may present as isolated neck masses in adults without typical clinical stigmata. Clues to the CT diagnosis include a lobulated appearance to the mass with intense but heterogeneous contrast enhancement. This appearance, in combination with results of fine needle aspiration, may be sufficiently diagnostic to preclude excisional biopsy.     

离子色谱法同时测定葡萄糖酸钙及其杂质(Cl-,SO42-)的含量

本文采用Waters ILC-1离子液相色谱仪,IC-PAK A50×4.6mm色谱柱,pH6.61×10^-3mol/L邻苯二甲酸溶液为流动相,430型电导检测器检测,由外标法和外标单点校正法同时测定了葡萄糖酸钙及其杂质(Cl^-,SO₄^2-)的含量。方法简便、快速,测定结果与中国药典法一致。外标法和外标单点校正法测定Cl^-,SO₄^2-的平均回收率为100.8%和100.2%,相关系数分别为0.9951(n=8)和0.9961(n=8)。     

Clinical significance of the 1-hour biopsy in renal transplantation.

Biopsy specimens were obtained from 43 transplanted kidneys at the time of excision from the donor but prior to revascularization, and 1 hr after revascularization. Two independent laboratories evaluated specimens by immunofluorescent techniques for the presence of IgM, IgA, IgG, C'3, and fibrin. Results from the two laboratories examined for reproducibility and immunological specificity, and correlated with clinical course. Results show that immunoglobulin deposition seen in the 1-hr renal biopsy specimens is of little significance, because: (1) immunoglobulin deposition was difficult to quantitate reliably, (2) the presence of immunoglobulins did not correlate with clinical course, and (3) the majority of immunoglobulin deposition detected was not immunologically specific, since it was most often either present prior to vascularization or disappeared with vascularization.