Search PubMed⌕ Search

Biomedical subjects

Y C Lin

Publications and source records attributed to Y C Lin.

At least 397 records · Page 22Linked to original sources
PubMedDate not supplied

Klebsiella brain abscess in adults.

BACKGROUND: We analyzed the clinical manifestations and therapeutic outcomes of Klebsiella brain abscesses. PATIENTS AND METHODS: The clinical data of 15 patients with Klebsiella brain abscesses, retrospectively collected over a 14-year period, were studied. RESULTS: The 15 patients included 13 cases of Klebsiella pneumoniae infection and two cases of Klebsiella oxytoca. All but one case were community-acquired infections. Locations of all of these abscesses were supratentorial. 12 cases involved a single abscess, and three involved multiple abscesses. Gas formation was also found in two cases (13%). Common predisposing factors included metastatic spread, chronic otitis media and neurosurgical procedures. Among these 15 patients, 11 were treated surgically and four received antibiotics alone. In total, 11 patients survived and four died, with an overall mortality rate of 26.7%. CONCLUSION: The clinical presentations and therapeutic outcomes varied according to the different Klebsiella species. While debilitating diseases were common in K. pneumoniae infections, they were not common in K. oxytoca infection. And while metastatic septic abscess is a well-known, devastating complication of K. pneumoniae septicemia, usually seen as a brain abscess with a gas-forming appearance, all of these K. oxytoca infections had both otogenic infections and more favorable outcomes.

Adult↗
PubMedDate not supplied

Ethanol acutely reduces LH and prolactin secretion: possible involvement by dopamine.

Ethanol (ETOH) administered acutely to castrate male rats caused a decline in pituitary luteinizing hormone (LH) and prolactin (PRL) secretion. This was associated with an elevation in hypothalamic and median eminence stores of dopamine (DA) that was related to the dose of alcohol given. Pituitary stalk transection (PST) resulted in a significant rise in plasma PRL levels compared to sham control animals, which suggests that DA in the hypophysial portal blood exerted an inhibitory influence on pituitary PRL secretion. The DA agonist bromocriptine failed to alter mean plasma LH levels in stalk-transected rats. The ETOH-treated castrated rats showed a significant rise in circulating PRL after injection of the DA receptor antagonist haloperidol metabolite II (HAL), but the administration of the DA receptor agonist R(-)-apomorphine HCL (APO) caused plasma PRL to decline to near undetectable levels. Plasma LH levels remained unchanged in the HAL- and APO-treated rats and were similar to those of sham controls. These results suggest that lactotroph DA receptors were still functional. Thus our previous finding of ETOH-induced reduction on LH secretion may be attributable to an inhibitory effect by DA on the luteinizing hormone-releasing hormone (LHRH) peptidergic neurons rather than a direct inhibition by DA on the pituitary gonadotroph.

Animals↗
PubMedDate not supplied

Immunohistochemical diagnosis of mouse hepatitis virus and mycoplasma pulmonis infection with murine antiserum.

This study established a modified alkaline phosphatase-labelled avidin-biotin-complex (ABC-AP) method for diagnosis of mouse hepatitis virus (MHV) and Mycoplasma pulmonis infection from formalin-fixed, paraffin wax-embedded sections, murine antibody-positive serum being used as the primary reagent. With this method, MHV antigen in cAnNCrj.Cg-Foxn1(nu)/Foxn1(nu) mice and M. pulmonis antigen in Wistar rats were immunolabelled in tissue sections. MHV antigen was clearly detected in samples of liver, stomach, caecal and colonic mucosa, and spleen. M. pulmonis antigen was demonstrated on the luminal surface of bronchiolar epithelial cells. This method may prove useful in diagnosis when commercial antisera are unavailable or when immunosuppression prevents serological diagnosis.

Animals↗
PubMedDate not supplied

Ornithine decarboxylase activity and polyamine content of the placenta and decidual tissue in the rat.

Measurements of ornithine decarboxylase (ODC) activity and of the amounts of putrescine, spermidine and spermine in the placenta and uterus of the pregnant rat and in decidual tissue of the pseudo-pregnant rat showed that these wax and wane with the growth rate of the tissues. Human term placenta has essentially no ODC activity, but placentae from 15-week human gestations have substantial amounts of enzyme. The ODC activity of the rat placenta increases 40-fold from day 10 to day 17 of pregnancy, then gradually decreases. The content of the polyamines in the placenta also reaches a peak on day 17. The ODC activity of the endometrium between implantation sites remains low until the end of pregnancy and then increases eight-fold on days 21 and 22. This may represent increased uterine activity in preparation for parturition. The ODC activity and the polyamine content of decidual tissue responds to administered oestradiol with increases that reach a peak within four hours. The ODC activity and polyamine content of decidual tissue decrease after the fifth day of decidualization. Nuclei isolated from decidual tissue respond to the addition of spermine or spermidine with an increase in the rate of RNA synthesis. Spermidine increases the elongation of RNA chains, but does not initiate the synthesis of new RNA chains in decidual nuclei.

Animals↗
PubMedDate not supplied

Fed-batch bioreactor strategies for microbial decolorization of azo dye using a Pseudomonas luteola strain.

A Pseudomonas luteola strain possessing azoreductase activity was utilized to decolorize a reactive azo dye (C. I. Reactive Red 22) with fed-batch processes consisting of an aerobic cell growth stage and an anaerobic fed-batch decolorization stage. The fed-batch decolorization was conducted with different agitation and aeration rates, initial culture volumes, dye loading strategies, and yeast extract to dye (Y/D) ratios, and the effect of those operation parameters on azo dye decolorization was evaluated. Dissolved oxygen strongly inhibited the azo reduction activity; thus aeration should be avoided during decolorization but slight agitation (around 50 rpm) was needed. With the periodical feeding strategy, the specific decolorization rate (v(dye)) and overall decolorization efficiency (eta(dye)) tended to increase with increasing feeding concentrations of dye, whereas substrate inhibition seems to arise when the feeding concentration exceeded 600 mg dye/L. In the continuous feeding mode, higher initial culture volume resulted in better eta(dye) due to higher biomass loading, but lower v(dye) due to lower dye concentration in the bioreactor. With a volumetric flow rate (F) of 25 mL/h, both v(dye) and eta(dye) increased almost linearly with the increase in the loading rate of dye (F(dye)) over the range of 50-200 mg/h, while further increase in F(dye) (400 mg/h) gave rise to a decline in v(dye) and eta(dye). As the F was doubled (50 mL/h), the v(dye) and eta(dye) increased with F(dye) only for F(dye) < 80 mg/h. The best v(dye) (113.7 mg dye g cell(-)(1) h(-)(1)) and eta(dye) (86.3 mg dye L(-)(1) h(-)(1)) were achieved at F(dye) = 200 mg/h and F = 25 mL/h. The yield coefficient representing the relation between dye decolorized and yeast extract consumed was estimated as 0.8 g/g. With F(dye) = 75 mg/h, the Y/D ratio should be higher than 0.5 to ensure sufficient supply of yeast extract for stable fed-batch operations. However, performance of the fed-batch decolorization process was not appreciably improved by raising the Y/D ratio from 0.5 to 1.875 but was more sensitive to the changes in the dye loading rate.

Azo Compounds↗
PubMedDate not supplied

Conjugation of maturation-related wheat-germ-lectin-binding proteins to caput epididymal sperm in co-cultures with corpus epididymal epithelial cells of BALB/c mouse.

In BALB/c mice, two maturation-related wheat-germ-binding glycoproteins (GP-49 and GP-83) are synthesized and secreted by corpus and cauda epididymis. A co-culture technique was used to investigate these glycoproteins in principal cells of corpus epididymis and the conjugation of these molecules on caput sperm. The principal cells were recovered from corpus epididymides of 4-week-old mice and cultured in RPMI 1640 medium supplemented with 10% fetal calf serum. After culturing for 3-4 days, most cells revealed epithelial cell-specific keratins in immunofluorescent localization with monoclonal antibody. By electron microscopy, a prominent nucleolus with well-extended euchromatin was revealed in the nucleus and the cytoplasm contained multivesicular bodies, and a well-developed Golgi apparatus with endoplasmic reticulum. By SDS-PAGE, GP-83 and GP-49 were revealed in the cell extracts and cell culture supernatants after incubation with 35S-methionine. Radiolabeled binding sites were also found on the surface of caput sperm co-cultured with the principal cells for 4 h in the presence of 35S-methionine. WGA-binding glycoproteins may be synthesized and secreted by the principal cells of corpus epididymis and conjugated to caput sperm during the epididymal transit.

Animals↗
PubMedDate not supplied

Dairy calcium is related to changes in body composition during a two-year exercise intervention in young women.

OBJECTIVE: Relationships between micronutrients and dairy product intake and changes in body weight and composition over two years were investigated. DESIGN: Two year prospective non-concurrent analysis of the effect of calcium intake on changes in body composition during a two year exercise intervention. SUBJECTS: 54 normal weight young women, 18 to 31 years of age. MEASURES OF OUTCOME: Mean intakes of nutrients of interest were determined from three-day diet records completed at baseline and every six months for two years. The change in total body weight and body composition (assessed by dual x-ray absorptiometry) from baseline to two years was also determined. RESULTS: Total calcium/kilocalories and vitamin A together predicted (negatively and positively, respectively) changes in body weight (R2 = 0.19) and body fat (R2 = 0.27). Further, there was an interaction of calcium and energy intake in predicting changes in body weight, such that, only at lower energy intakes, calcium intake (not adjusted for energy) predicted changes in body weight. CONCLUSIONS: Regardless of exercise group assignment, calcium adjusted for energy intake had a negative relationship and vitamin A intake a positive relationship with two year changes in total body weight and body fat in young women aged 18 to 31 years. Thus, subjects with high calcium intake, corrected by total energy intake, and lower vitamin A intake gained less weight and body fat over two years in this randomized exercise intervention trial.

Absorptiometry, Photon↗
PubMedDate not supplied

Clinical benefit and response in patients with gastric cancer to weekly 24-hour infusion of high-dose 5-fluorouracil (5-FU) and leucovorin (LV).

BACKGROUND: A prospective study evaluated the efficacy and correlation of different outcome measurements, including the WHO response criteria and clinical benefit (CB), to weekly high-dose 5-FU and LV for patients with advanced gastric cancer. PATIENTS AND METHODS: Thirty-nine chemotherapy-naive patients were enrolled from Sep. 1996 to Oct. 1997. The treatment consisted of a 24-hour continuous infusion of 5-FU 2600 mg/m2 & LV 150 mg weekly for 6 weeks with a subsequent 2-week break. The responses were evaluated by CB and WHO criteria at the end of the 8th week, then at 8-week intervals. RESULTS: There were 21 male and 18 female patients with a median age of 56 years. The median Karnofsky performance score was 70%. Thirty-six patients were evaluable for WHO criteria, and 12 (33.3%) had partial response, 12 (33.3%) had stable disease and 12 (33.3%) had progressive disease. Twenty-one of the 35 (60%) evaluable patients for CB were found to have a positive response. There was a significant correlation between WHO response and CB. The median survival was 10.5 months for CB responders, while the median survival among the CB non-responders was 5 months only. CONCLUSIONS: This study found that this regimen yielded a 60% CB, despite a 33% WHO response rate. Improvement in CB resulted in an improvement in survival as well as the correlation between CB and WHO response, and suggested the value of CB as an alternative indicator for clinical response.

Adult↗
PubMedDate not supplied

17 beta-estradiol-regulated expression of protein tyrosine phosphatase gamma gene in cultured human normal breast and breast cancer cells.

BACKGROUND: Protein tyrosine phosphatase gamma (PTP gamma) has been implicated as a potential tumor suppressor gene in kidney and lung adenocarcinomas. We have previously shown that PTP gamma mRNA expression levels are lower in DES-induced kidney tumors than in normal kidneys of Syrian hamsters. The goals of the present study were to determine if PTP gamma mRNA is present in both normal and cancerous human breast cells, and to investigate the estrogenic regulation of PTP gamma mRNA expression in these cell types. METHODS: Primary cultured human breast cells derived from surgical specimens of mammoplasty and breast cancer patients, as well as human breast cancer cell lines were used for the study. RT-PCR and RNase protection assay was utilized to detect and quantify levels of PTP gamma mRNA among the cell types used and between control and 17 beta-estradiol (E2)-treated cells. Transient transfection of human estrogen receptor (ER) into MDA-MB-231 human breast cancer cells was performed to establish the role of ER in the regulation of PTP gamma mRNA expression. RESULTS: The results show that PTP gamma mRNA is expressed in primary cultured human breast cells isolated from mammoplasty and breast cancer patients, as well as in human cancer cell lines, and that E2 significantly inhibits PTP gamma expression in ER-positive human breast cancer cells via an ER-mediated mechanism. We show that PTP gamma mRNA levels are lower in human breast cancer cells than in normal human breast cells. Furthermore, we report that PTP gamma mRNA expression is inhibited by E2 in a dose-dependent manner in primary cultured breast cells. After treatment with 20 nM E2 for 24 hours, PTP gamma mRNA was significantly suppressed in primary cultured cancerous and non-cancerous cells from breast cancer patients, as well as in the ER-positive MCF-7 cell line by 50%, 85%, and 66%, respectively. In contrast, the PTP gamma mRNA expression levels did not change in similarly treated ER-negative MDA-MB-231 cells. Sensitivity to E2-induced suppression could be restored (94% inhibition) by transfecting MDA-MB-231 cells with an ER expression plasmid. CONCLUSIONS: Our results are the first to suggest that PTP gamma is a potential estrogen-regulated tumor suppressor gene in human breast cancer which may play an important role in neoplastic processes of human breast epithelium.

Breast↗