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61.
Ferritin immunohistochemistry as a marker for microglia   总被引:1,自引:1,他引:0  
Summary An immunohistochemical analysis of formalin-fixed, paraffin-embedded brain sections was performed with antisera against holoferritin and the light(L)-subunit of ferritin. Sections immunostained using anti-glial fibrillary acidic protein (GFAP), Ricinus communis agglutinin-1 (RCA-1) stain for microglia and iron stain (Berlin blue stain) were compared. The L-subunit of ferritin was purified from normal human spleen according to the modified scrapie-associated fibrils purification, and the antiserum was raised in a rabbit. Both ferritin antisera positively stained resting and, more markedly, reactive microglia, both of which were also stained with RCA-1 but not with GFAP. Ferritin-positive resting microglia were seen more abundantly in cerebral and cerebellar cortices than in white matter. The advantages of ferritin antisera over RCA-1 are as follows. (1) RCA-1 heavily stains blood vessels, while anti-ferritin does not, hence the microglial cells are more readily visualized with ferritin immunohistochemistry. (2) Reactive microglia and macrophages are more strongly stained with anti-ferritin. (3) The staining intensity of ferritin is independent of the length of tissue fixation in formalin. However, anti-ferritin is inferior to RCA-1 in staining resting microglia with a scanty cytoplasm, especially in the white matter, probably because the former recognizes cytoplasmic components, while the latter recognizes cell membrane. Iron stain only gave a reaction to microglial cells in brains with neurosyphilis and to hemosiderin-laden macrophages. Thus, in addition to RCA-1, ferritin antisera are useful as a microglia marker in formalin-fixed, paraffin-embedded sections.Supported in part by Dr. A. Kondo, Department of Neuropathology, Neurological Institute, Kyushu University  相似文献   
62.
Endoscopic submucosal dissection (ESD) for colorectal cancer is not widely accepted because of its technical difficulty and the risk of perforation. In addition, the risk of peritonitis cannot be completely eliminated even if a perforation is closed successfully. Reported here are two cases of early colon cancer in which the patients sustained iatrogenic perforations of the ascending colon during conventional endoscopic mucosal resection and of the sigmoid colon during ESD, respectively, requiring abdominal decompression with an 18 G Medicut needle. Both of these perforations were successfully treated by endoscopic clipping. In conclusion, conservative medical management may be possible in patients who have undergone successful closure of colonic perforations using endoscopic clipping. In order to perform immediate endoscopic closure, abdominal decompression has been useful to decrease patient discomfort and colonic lumen collapse. Now, CO2 insufflation is being used effectively for the prevention of pneumoperitoneum.  相似文献   
63.
Obstructive sleep apnea syndrome (OSAS) is recognized as one of the risk factors of hypertension and cardiovascular disorders. In the current study, we hypothesized that the hypoxic stress and oxidative stress caused by obstructive sleep apnea would increase circulating adrenomedullin (ADM) levels in untreated OSAS patients as compared to an age and body mass index (BMI)-matched control group and an age-matched, but normal-BMI control group. We further hypothesized that nasal continuous positive airway pressure (nCPAP) treatment may decrease OSAS-induced hypoxic stress, oxidative stress and ADM levels. To examine these hypotheses, we measured circulating ADM and reactive oxygen species (ROS) from leukocytes before and after nCPAP therapy in OSAS patients. The circulating levels of ADM and amount of ROS in untreated OSAS patients were significantly greater than those in the controls. No differences in ADM levels were found between the increased-BMI controls and normal-BMI controls. We observed that nCPAP treatment decreased sleep apneas, nocturnal oxyhemoglobin desaturation, the circulating ADM, and ROS production by leukocytes in OSAS patients. The ADM levels were associated with the magnitude of oxyhemoglobin desaturation rather than the number of sleep apneas. These observations suggest that nCPAP therapy could reduce OSAS-induced nocturnal hypoxemia, generation of ROS, and ADM in patients with OSAS.  相似文献   
64.
A 23-year-old man was admitted for an aortic root aneurysm with mild aortic valve regurgitation (AR) and a small pressure gradient. At surgery, findings of aortic valve, one normal left posterior commissure and very rudimentary right anterior commissure, was compatible with the uni-commisural aortic valve. Aortic root replacement with valve-sparing technique was performed. Four years later no residual AR was observed.  相似文献   
65.
By the combined use of agar diffusion, agar vapor and agar vapor-inhibitory assays, contribution of the vapor activity of essential oils was quantitatively estimated. The test organisms were Trichophyton mentagrophytes and Aspergillus fumigatus. Agar vapor assay was used to confirm the vapor activity of the oils. The parameter delta defined as a contribution index of the vapor activity was calculated by (1 - b-c/a-c) x 100, where a is inhibitory diameter in the diffusion assay, b is inhibitory diameter in the vapor-inhibitory assay and c is diameter of the sealed ring in the vapor-inhibitory assay (21 mm). Many of the essential oils examined showed a delta value near 100, thus providing the major contribution of the vapor activity to the inhibitory diameter. Essential oils containing aldehyde as major constituent showed low delta value, indicating the major inhibition was due to agar diffusion. Major essential oil components behaved similarly; the delta value was increased in the following order: aldehyde < phenol < alcohol < ester, oxide, hydrocarbon, indicating the enhanced contribution of the vapor activity in that order.  相似文献   
66.
Exfoliative toxin D (ETD) was identified recently as a new exfoliative toxin serotype. Like other exfoliative toxins, ETD induces intra-epidermal cleavage through the granular layer of the epidermis of neonatal mice. The distribution of ETD production was investigated in Staphylococcus aureus isolates from infected and colonised patients in France. The etd gene was found in 55 (10.5%) of 522 isolates tested. Isolates responsible for bullous impetigo and generalised staphylococcal scalded skin syndrome did not harbour etd, but etd was significantly more frequent in isolates causing cutaneous abscesses and furuncles. Most etd- and Panton-Valentine leukocidin-positive strains belonged to the clone of community-acquired methicillin-resistant S. aureus spreading currently throughout France.  相似文献   
67.
Since the prevalence and clinical characteristics of young-onset hypertension are still to be elucidated, we performed targeted-screening at an annual university health check-up for two consecutive years. Out of 16,464 subjects in 2003 and 17,032 in 2004 that were aged less than 30 years, 22 and 26 students (all males) exhibited high blood pressure (BP), respectively, on three occasions during casual BP measurements at the Tohoku University Health Center (systolic and diastolic BP of 140 and/or 90 mmHg or greater, respectively). These students were asked to measure their BP at home, and 9 subjects in total were diagnosed as having essential hypertension (EH). The remaining students were diagnosed as having white coat hypertension (WCH). In 8 out of 9 EH students, their father and/or mother had also been treated with antihypertensive medication. Adjustment by attendance ratio for each BP measurement suggested that the incidence of EH was around 0.1% and that of hypertension (EH and WCH) was around 0.5% in university students aged less than 25 years, since most of the subjects and hypertensive students were between 18 and 24 years old. Body mass index of the EH, which was more than 25 kg/m2 (overweight), was significantly higher than that with WCH. In conclusion, the combination of repeated casual BP measurements and home BP effectively identified young-onset EH. The clinical parameters indicated that male gender, genetic background, and excessive weight were risk factors for young-onset hypertension.  相似文献   
68.
Ryo Hattori  MD    Tateki Kubo  MD    Kenji Yano  MD  PhD    Atsushi Tanemura  MD    Yuji Yamaguchi  MD  PhD    Satoshi Itami  MD  PhD    Ko Hosokawa  MD  PhD 《Dermatologic surgery》2003,29(10):1071-1072
BACKGROUND: Nevus lipomatosus cutaneous superficialis (NLCS) is a relatively rare condition. Although NLCS can affect any region of the entire body, no case of NLCS in the clitoris has ever been reported. OBJECTIVE: To report a case of NLCS of the clitoris that presented manifestations that were similar to female pseudohermaphrodism. METHODS: This is a case report and review of the literature. RESULTS: A congenital, soft, skin-colored lesion of the clitoris in a 1-year-old girl resembled female pseudohermaphrodism. It was resected, and the histologic diagnosis was NLCS. Postoperatively, there was no subsequent change in the lesion during the 3-year follow-up period. CONCLUSION: We reported a case of congenital solitary NLCS of the clitoris. Although NLCS might be a relatively rare condition, we should consider it in the differential diagnosis of female pseudohermaphrodism.  相似文献   
69.
OBJECTIVE: The effect of tonicity changes in nebulizer solutions and irrigations on nasal mucosa is not well known. The present study aims to determine the basic mechanism of hypertonic solution on airway epithelial barrier. STUDY DESIGN AND SETTING: We investigated the electrical potential difference (PD) that is influenced by both active transport and the transepithelial electrical resistance of the epithelial mucosa in the human nose in vivo. The short circuit current (SCC) revealed net ion transport across the epithelium in the guinea pig trachea in vitro. Finally, the size dependency of macromolecules across the tracheal mucosa was determined in vitro using FITC-labeled dextrans of different sizes. RESULTS: PD was significantly decreased after topical application of hypertonic solution both in human and in guinea pig nose. SCC was significantly decreased after application of hypertonic solution. The transport of these dextrans from the basolateral to the apical side was not increased significantly after apical application of hypertonic saline. CONCLUSIONS: Hypertonic saline enhances the electrical permeability of the airway epithelial mucosa but not transport of macromolecule in the short term.  相似文献   
70.
BACKGROUND: Gitelman's syndrome (GS) is an autosomal recessive disorder resulting from inactivating mutations in the thiazide-sensitive Na-Cl co-transporter (NCCT) gene. To date, almost 90 mutations have been identified. It is possible that there is a population-specific distribution of mutations. In this study, we analysed mutations in the NCCT gene of seven Japanese patients with GS. METHODS: Peripheral blood mononuclear cells were isolated from patients with GS, their family members and healthy control subjects. A mutation analysis of the NCCT gene was performed completely by direct automated sequencing of polymerase chain reaction-amplified DNA products. In patients with a deletion or splice site mutation, we undertook cDNA sequence analysis. RESULTS: We identified nine mutations. Five of them [c.185C>T (Thr60Met), c.1712C>T (Ala569Val), c.1930C>T (Arg642Cys), c.2552T>A (Leu849His) and c.1932delC] have been reported in Japanese patients, but not in GS patients from other ethnic groups. The remaining four mutations [c.7A>T (Met1Leu), c.1181_1186+20del26, c.1811_1812delAT and IVS16+1G>A] were novel. In cDNA derived from a patient with c.1181_1186+20del26, a deletion of exon 9 and a frameshift at the start of exon 10 were observed. In cDNA derived from patients with IVS16+1G>A, an additional 96 bp insertion between exons 16 and 17 was observed. Six out of seven patients were compound heterozygotes, and the remaining one carried a single heterozygous mutation. CONCLUSIONS: We found four novel mutations in the NCCT gene in seven Japanese patients with GS. Moreover, our study suggests that the distribution of mutations in the NCCT gene in Japanese GS patients potentially differs from that in other populations.  相似文献   
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