Delineatino of the da-Silva syndrome

We present a 6-month-old boy with agenesis of the corpus callosum, hypertonicity, severe growth and psychomotor retardation, microcephaly, large prominent ears, and delayed bone age. Similarity of his manifestations to these in 3 sibs described by da-Silva in 1988 suggests initial delineation of the da-Silva syndrome. © 1994 Wiley-Liss, Inc.     

Histamine release from rat mast cells sensitized with mouse antiserum

The characteristics of the antigen-induced and nonantigen-induced histamine release from rat peritoneal mast cells sensitized in vitro with mouse anti-ovalbumin serum were investigated. The effects of some antiallergic drugs on these release reactions were also studied.Besides antigen-specific IgE antibody, heat-labile factor(s) responsible for the non-antigen-induced histamine release were found in mouse antiserum. Such factors were also present in normal mouse serum. In the absence of antigen, the combination of phosphatidyl serine and Ca⁺⁺ induced some extent of histamine release from mast cells treated with these factors.From the present results it is suggested that quercetin selectively and verapamil primarily act to block calcium-gate opening resulting from antigen-antibody interaction on the mast cell membrane, while theophylline and disodium cromoglycate selectively inhibit the passage of calcium through open calcium channels.     

The detection and quantification of highly reactive oxygen species using the novel HPF fluorescence probe in a rat model of focal cerebral ischemia

A novel fluorescence probe, 2-[6-(4'-hydroxy) phenoxy-3H-xanthen-3-on-9-yl] benzoic acid (HPF) was used to investigate the generation of highly reactive oxygen species (hROS) under ischemia both in vitro and in vivo. In the in vitro study, HT 22 cells were used to demonstrate that was predominantly detected in the cytoplasm, which coincides with the location of the mitochondria and then its HPF fluorescence gradually increased from 6 to 24 h due to glutamate induced oxidative stress. In the in vivo study, the permanent and transient middle cerebral artery occlusion (MCAO) was induced in rats. Brain slices were incubated in an artificial medium containing HPF. The area of enhanced HPF fluorescence existed in both the ischemic core and the peri-infarct area at 4h after MCAO in both permanent and transient MCAO models. The area extended beyond the boundary of the ischemic damage into biochemically viable tissue. The enhanced fluorescent intensity following transient MCAO was higher than that observed in the permanent MCAO model. Hydroxyl radical scavenger, MCI-186 significantly suppressed the enhanced fluorescence intensity. This study demonstrated that HPF has a high sensitivity and specificity for the detection of hROS in focal cerebral ischemia as well as in a cellular model of oxidative stress.     

Plasma extravasation induced by dietary supplemented histamine in histamine-free mice

Histidine decarboxylase (HDC) synthesizes endogenous histamine from histidine in mammals. To evaluate the role of histamine in skin allergic reaction, we used HDC gene knockout mice lacking histamine. No plasma extravasation reaction was observed in HDC-/- mice after passive cutaneous anaphylaxis (PCA) test. Compound 48/80, a mast cell granule depletor, produced plasma extravasation inHDC+/+ mice but no extravasation in HDC-/- mice. Interestingly, orally administered histamine was distributed in the skin in HDC-/- mice and in these histamine-supplemented mice the plasma extravasation reaction was observed after the injection of compound 48/80 and the PCA test. Cultured bone marrow-derived mast cells of HDC-/- mice took up histamine from the histamine-supplemented medium into the secretory granules. The absorbed histamine was released in response to the same antigen and antibody combination used as in PCA test. In contrast to the immediate-type response, the delayed-type hypersensitive response, observed as a thickening of the ear skin after trinitrochlorobenzene challenge (following sensitization), showed no differences between HDC+/+ and HDC-/- mice. Therefore, among the allergic skin reactions, histamine is revealed to be an important mediator especially for the plasma extravasation in an immediate-type allergy model.     

Comprehensive mutational analysis of the VHL gene in sporadic renal cell carcinoma: relationship to clinicopathological parameters

To delineate more precisely the somatic von Hippel-Lindau disease (VHL) gene alteration as well as to elucidate its etiologic role in renal tumorigenesis, we examined a total of 240 sporadic renal cell carcinomas (RCCs) for somatic VHL gene alterations by DNA-SSCP followed by sequencing, methylation-specific PCR assay, microsatellite LOH study, and Southern blot analysis. Intragenic mutation of the VHL gene was found exclusively in clear-cell or variant-type RCCs at a frequency of 51% (104/202). Hypermethylation of the VHL promoter region was detected in an additional 11 clear-cell RCCs. Microsatellite analysis demonstrated that LOH of the VHL locus was found in 140/155 (90%) informative clear-cell RCCs. The VHL gene therefore seems to be inactivated in a two-hit manner by intragenic mutation or hypermethylation plus allelic loss in clear-cell RCC. Genomic rearrangement of the VHL gene detected by Southern analysis was not found (0/216 cases); this is in contrast to germ lines in which Southern aberrations consisted of 7-19% of the mutations. Clinicopathologic data demonstrated that VHL mutation/LOH did not vary according to tumor progression in clear-cell RCC, including tumor diameter, stage, grading, distant metastasis, and lymph node metastasis. Interestingly, VHL mutation was significantly less frequent in RCCs occurring in younger (< or = 55 years) than that in older (> or = 56 years) patients. These data suggested that the inactivation of the VHL tumor-suppressor gene is a specific genetic change in clear-cell RCC, and that it may occur at an early or first step in the clear-cell tumorigenic pathway rather than as a late event.     

Preoperative retrolisthesis as a predictive risk factor of reoperation due to delayed-onset symptomatic foraminal stenosis after central decompression for lumbar canal stenosis without fusion

Background Context

For patients diagnosed with lumbar central canal stenosis with asymptomatic foraminal stenosis (FS), surgeons occasionally only decompress central stenosis and preserve asymptomatic FS. These surgeries have the potential risk of converting preoperative asymptomatic FS into symptomatic FS postoperatively by accelerating spinal degeneration, which requires reoperation. However, little is known about delayed-onset symptomatic FS postoperatively.

Platelet count and indoor cold exposure among elderly people: A cross-sectional analysis of the HEIJO-KYO study

Background

Excess mortality from cardiovascular disease during cold seasons is a worldwide issue. Although some physiologic studies suggests that platelet activation via cold exposure may cause an increased incidence of cardiovascular disease in winter, the influence of indoor cold exposure in real-life situations on platelet (PLT) count remains unclear.