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Biochemical mechanisms underlying acrylamide induced neurotoxicity were examined using an in vitro model consisting of sagittal slices of rat brain. Incubation of brain slices under oxygen in artificial cerebrospinal fluid containing acrylamide produced a dose and time dependent inhibition of glyceraldehyde 3-phosphate dehydrogenase (GAPDH). Lysosomal enzymes, acid phosphatase, N-acetyl glucosaminidase and beta-glucuronidase decreased in a similar manner, while no changes were observed in the activity of Na+K+ATPase, cytochrome c oxidase and lactate dehydrogenase. Incubation of slices with two structurally related compounds, acetamide (a non-neurotoxic amide) and methylene bis-acrylamide (a weak neurotoxin), indicated that acrylamide selectively inhibited GAPDH, enolase and N-acetyl glucosaminidase at low concentration; similar doses of acetamide and methylene bis-acrylamide did not have the same effect on brain slices. Incubation with acrylamide depleted glutathione levels in slices, and the addition of glutathione to the incubation medium prevented acrylamide induced inhibition of GAPDH and lysosomal enzymes. Time dependent inhibition of lysosomal enzymes was also observed in vivo, in the brain and sciatic nerve of rats following a single dose of acrylamide. These results demonstrate that both in vitro and in vivo, lysosomal enzymes are also inhibited following acrylamide exposure. The rat brain slice model exhibits both selectivity and sensitivity towards neurotoxicants and hence, may prove to be an useful in vitro model for the mechanistic evaluation of neurotoxicity. 相似文献
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The records of two groups of patients (358 schizophrenics and 69 neurotics), attending the community mental health center of the Johns Hopkins Hospital, were reviewed to assess the extent and severity of reported medical problems. Results indicate that 38% of the schizophrenics and 53% of the neurotics report medical problems, but schizophrenics present with serious medical problems more often than do the neurotics. The authors draw attention to the need for properly assessing the severity of these medial problems and for adequately coordinating psychiatric and medical care. Strategies to overcome these difficulties are suggested. 相似文献
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Pai A Kulkarni MG Koppikar GV 《The Journal of the Association of Physicians of India》1999,47(8):795-797
The current study is carried out to find the in-vitro susceptibility of N. gonorrhoeae to Ciprofloxacin, Norfloxacin, Gentamycin etc. in 110 isolates obtained from acute gonococcal urethritis confirmed by smear examination. The isolates obtained are from the patients attending the Skin and STD Clinic of a teaching hospital, clinically diagnosed as suffering from acute gonococcal urethritis. Antibiotic susceptibility test was done by Kirby Bauer disc diffusion technique. Four to five similar well isolated colonies of the gonococcal strains were picked up with a wire loop and transferred to 5 cc of sterile trypticase soya broth (TSB). Tubes were incubated at 36 degrees C. GC agar base plates were inoculated with suspensions using a sterile cotton swab. Antibiotic discs were placed on these plates. The plates were incubated at 35 degrees C for 18-24 hours in a candle jar with 5-10% CO2. The plates were then observed to note the zones of inhibition around the discs. 87.27% of isolated strains were inhibited by norfloxacin at an MIC of 0.06 mu gm/ml; 89.08% of the strains were inhibited by ciprofloxacin at an MIC of 0.025 mu gm/ml. All the strains (110) were inhibited by ciprofloxacin at a concentration of 0.2 mu gm/ml. Gentamycin sensitivity was 86.36%. Out of 110 patients, 85 were treated with norfloxacin of which 81 (95.29%) were cured. Twenty five were treated with ciprofloxacin of which 24 (96%) were cured. This study shows high sensitivity of N. gonorrhoeae to norfloxacin and ciprofloxacin. 相似文献
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Fine needle aspiration cytology plays an important role in the preoperative assessment of soft tissue neoplasms. In a 40-year-old man presenting with a large soft tissue mass in the posterior aspect of thigh a diagnosis of myxoid liposarcoma was suggested on FNAC. Scrape smears of the excised mass showed an additional finding of round cell component. Histopathology confirmed combined myxoid and round cell liposarcoma (grade 2), which behaves aggressively when compared to pure myxoid liposarcoma. 相似文献
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Ritscher-Schinzel cranio-cerebello-cardiac (3C) syndrome: report of four new cases and review 总被引:3,自引:0,他引:3
Ritscher-Schinzel syndrome, also known as the 3C syndrome, is a rare, autosomal recessive syndrome characterized by craniofacial, cerebellar, and cardiac anomalies. Cardiac manifestations include ventricular septal defect, atrial septal defect, tetralogy of Fallot, double outlet right ventricle, hypoplastic left heart, aortic stenosis, pulmonic stenosis and other valvular anomalies. Central nervous system anomalies include Dandy-Walker malformation, cerebellar vermis hypoplasia and enlargement of the cisterna magna. Craniofacial abnormalities seen are cleft palate, ocular coloboma, prominent occiput, low-set ears, hypertelorism, down-slanting palpebral fissures, depressed nasal bridge and micrognathia. Dandy-Walker malformation, posterior fossa cyst, hydrocephalus and congenital heart defect are common malformations that may occur in isolation or as a part of many syndromes. Accurate genetic diagnosis and counseling require detailed analysis of the external as well as the internal anatomy and knowledge of the relative frequencies of various malformations in syndromes that may have overlapping clinical signs. We have had the opportunity recently to study four cases of the Ritscher-Schinzel syndrome. A review of all reported cases is presented and an attempt made to define the minimum diagnostic criteria for the Ritscher-Schinzel syndrome. Of the nine craniofacial anomalies commonly reported as a part of the Ritscher-Schinzel syndrome, we consider two i.e., cleft palate and ocular coloboma, to be readily and objectively ascertainable. The other seven craniofacial traits, however, are somewhat subjective, require expert interpretation and are sometimes difficult to ascertain in a newborn or stillborn fetus. These are prominent forehead, prominent occiput, hypertelorism, down-slanting palpebral fissures, low-set ears, depressed nasal bridge and micrognathia. At least four of these were present in all cases that had a secure diagnosis of the Ritscher-Schinzel syndrome. Thus, the criteria we propose to establish the diagnosis of the Ritscher-Schinzel syndrome in a chromosomally normal sporadic case are the presence of cardiac malformation other than isolated patent ductus arteriosus, cerebellar malformation, and cleft palate or ocular coloboma or four of the following seven findings: prominent forehead, prominent occiput, hypertelorism, down-slanting palpebral fissures, low-set ears, depressed nasal bridge, and micrognathia. 相似文献