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N Kang

Publications and source records attributed to N Kang.

30 records · Page 2Linked to original sources

[Detection of epidermal growth factor receptor gene amplification in human laryngeal carcinomas by means of fluorescence in situ hybridization].

OBJECTIVE: To detect epidermal growth factor receptor(EGFR) gene amplification in human laryngeal carcinoma Hep-2 cell line and laryngeal carcinoma tissues. METHODS: The technique of fluorescence in situ hybridization(FISH). RESULTS: The EGFR gene amplification of a laryngeal carcinoma Hep-2 cell line and 5 laryngeal carcinoma tissues were detected by FISH. In the metaphase chromosome and interphase nuclei of Hep-2 cell line and 2 laryngeal carcinoma tissues, distinct cluster and multiple dot signals were found. In the interphase nuclei of the other 3 laryngeal carcinoma tissues, no increase in the number or extent of the hybrid signals was found. CONCLUSION: Compared with normal diploid cell, the EGFR gene amplification was observed at different levels ranging from 2 to 8 folds in metaphase chromosome and interphase nuclei of Hep-2 cell line and 2 laryngeal carcinoma tissues while no amplification was observed in the other 3 laryngeal carcinoma tissues. The results demonstrate that quantitative detection of amplified gene by FISH in the metaphase chromosome and interphase nuclei is useful for detection of laryngeal carcinoma tissues.

ErbB Receptors↗

In vivo targeting of malignant melanoma by 125Iodine- and 99mTechnetium-labeled single-chain Fv fragments against high molecular weight melanoma-associated antigen.

Monoclonal antibodies (MAbs) against high-molecular-weight melanoma-associated antigen (HMW-MAA) have been used in vivo to target melanoma. More recently, single chain Fv (scFv) antibody fragments against HMW-MAA have been described that may improve melanoma targeting. However, there have been few in vivo studies with antimelanoma scFvs because these have proved difficult to label with isotopes (e.g., 99mTc) suitable for imaging. We have generated a series of scFvs against HMW-MAA by chain shuffling and antibody phage selection on melanoma cells. In preliminary experiments we identified one scFv (RAFT3) as suitable for in vivo melanoma targeting. Direct radiolabeling of RAFT3 scFv with 99mTc was simple, yielding a radiochemical purity of >90%. The label remained stable for 24 h in vitro. 125I- and 99mTc-labeled RAFT3 scFv were tested in a nude mouse xenograft model for human melanoma and were compared with the parent MAb LHM2 and its F(ab')2 fragment versus nonmelanoma-specific MAb and scFv. RAFT3 scFv accumulated specifically in the tumor and showed greater tumor specificity compared with LHM2 with faster pharmacokinetics (t(1/2)alpha, 8 min; t(1/2)beta, 189 min; and t(1/2)alpha, 37 min; t(1/2)beta, 384 min, respectively) and reduced background in liver, lung, and spleen. Nonspecific accumulation of 99mTc-labeled RAFT3 scFv in the kidney was high but tumor:normal tissue ratios were better compared with 125I-labeled RAFT3 scFv and LHM2 F(ab')2. Overall, tumor-targeting efficiency at equivalent time points was scFv > IgG > F(ab')2 in good agreement with previously described scFvs engineered for 99mTc labeling. We discuss the potential use of RAFT3 scFv for imaging and therapy of metastatic melanoma.

Animals↗

Domestic violence in medical practice: a new approach for Louisiana physicians.

This article describes the role of the physician in reporting domestic violence, the current situation in Louisiana, and how California addressed this problem. The author advocates a statewide comprehensive domestic violence education program for medical students, residents, and physicians. She describes a program which would focus on awareness, screening, diagnosis, and referral.

California↗

Differential expression of protein kinase C isoforms in streptozotocin-induced diabetic rats.

BACKGROUND: The cellular effects of hyperglycemia are mediated by protein kinase C (PKC). However, PKC consists of several distinct isoforms, and their contribution to the pathogenesis of diabetic complications in different organs is not clear. We investigated the expression and translocation of PKC isoforms alpha, betaI, betaII, delta, epsilon, and zeta in kidney, heart, and aorta from diabetic rats. METHODS: Hyperglycemia was induced with streptozotocin (70 mg/kg) in the rat. After four weeks, PKC isoform expression was assessed by Western blot after tissue fractionation and by immunohistochemistry. RESULTS: Streptozotocin increased blood glucose from 117.0 +/- 3.6 to 510.0 +/- 19.4 mg/dl (N = 8, P < 0.01) and induced albuminuria. PKC isoforms alpha, beta, delta, epsilon, and zeta were all detected in control animals. Western blot showed increased PKC alpha expression in kidney and heart (160% and 170%, respectively). PKC betaI, betaII, and delta expression was not influenced by hyperglycemia. PKC zeta was decreased in diabetic animals in both tissues by 60%. The membrane association of PKC alpha and PKC epsilon was increased; however, the relative amount of PKC in the particulate fraction was not influenced by hyperglycemia. Immunohistochemistry revealed a marked increase in PKC alpha immunoreactivity in renal glomeruli and interstitial capillaries, cardiac capillaries, and skeletal muscle, as well as in the endothelial cells of larger arteries. PKC beta showed a small decrease in the glomeruli. PKC epsilon was increased in renal tubules in diabetic rats but was decreased in the myocardium. PKC zeta was expressed in both myocardial and glomerular cells but was decreased during hyperglycemia. Our results demonstrate that PKC isoforms are differentially regulated in kidney and heart in diabetes. High glucose increases PKC alpha expression, whereas PKC zeta is down-regulated. The finding that PKC alpha is mostly increased in endothelial cells supports a role for PKC alpha in functional endothelial disturbances observed in diabetes.

Animals↗

A case of streptococcal myositis (misdiagnosed as hamstring injury).

Streptococcal myositis is a very rare bacterial infection of muscle with a high mortality. Diagnosis is difficult because of the paucity of clinical signs and symptoms at the onset. However, presentation of the disease appears to have changed over the last 50 years. A case of streptococcal myositis is presented (misdiagnosed as hamstring injury), which more closely reflects the current presentation of the disease. Some of the features that may help emergency clinicians to recognise the onset of the condition are highlighted.

Adult↗

Hepatic histology and the development of esophageal varices in biliary atresia.

Histological features in liver biopsy specimens taken from 71 infants at the time of surgery for biliary atresia (portoenterostomy) were analyzed using a scoring system and compared with an endoscopic grading of esophageal varices performed at a mean age of 3.4 years. The analysis showed no correlation between a "global" score, which represented the severity of all histological changes in the original biopsy specimen, and the severity of esophageal varices. Further analysis also showed no correlation with any individual histological feature (eg, fibrosis). These findings failed to confirm a previous study, which suggested a relationship between liver changes at surgery and the later development of esophageal varices in children with biliary atresia.

Biliary Atresia↗

Abnormal chloride conductance in multidrug resistant HL60/AR cells.

Chloride channel currents were measured in drug sensitive parental HL60 and multidrug resistant (MDR) subline HL60/AR cells, using a whole cell patch-clamp technique. In addition, the in vitro effects of 4,4' diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS), a Cl- channel blocker, on intracellular accumulation and sensitivity to daunorubicin and intracellular pH (pH(i)) in HL60 cells were examined. Baseline DIDS blockable Cl- currents were consistently lower in HL60/AR cells (0.9 pA/pF) as compared to HL60 cells (7.0 pA/pF). Similarly cAMP-activated Cl- currents were minimal in HL60/AR cells (0.2 pA/pF) as compared to HL60 cells (8 pA/pF). In vitro treatment of drug sensitive HL60 cells with DIDS resulted in concentration-dependent decreased accumulation and increased resistance to daunorubicin and decreased pH(i). These data show that altered Cl- permeability is associated with MDR and suggest that Cl- channels may play a role in MDR.

4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid↗

The pathological effects of glove and condom dusting powders.

Dusting powders are used on latex gloves and condoms. They help to release these products from their moulds during manufacture and facilitate processing and donning. Dusting powders are also used on contraceptive diaphragms, sanitary napkins and in toiletries. There are numerous dusting powders in current use around the world. At present a consensus exists about the best dusting powder to use on surgical gloves, based on data about the safety of these agents in humans, as well as their manufacturing qualities. No such consensus exists for the use of dusting powders in other situations. However, there is uncertainty about whether dusting powders used in situations other than on surgical gloves are responsible for harmful effects. This study uses intraperitoneal injections in rats to examine the pathological effects of dusting powders that are in current use on surgical gloves and condoms. We suggest that dusting powders may be a source of morbidity when used in situations other than on surgical gloves and confirm the findings of previous investigators that the dusting powders we tested differ in their ability to produce pathological effects.

Aluminum Silicates↗

Melanoma antigens and targets for vaccination.

Metastatic melanoma is at present incurable by conventional therapy. However, encouraging improvements in patients survival have been obtained in clinical trials with melanoma vaccines as active specific immunotherapy. This review will discuss recent developments in melanoma vaccines.

Antigens, Neoplasm↗