Immunohistochemical study of the expression of drug-resistant proteins in large cell neuroendocrine carcinoma of the lung

Objectives: In 1999, the World Health Organization categorized pulmonary large cell neuroendocrine carcinoma as a variant of large cell carcinoma. However, an optimal treatment for large cell neuroendocrine carcinoma has not been established yet. Recently, multimodality therapy combining both surgery and adjuvant chemotherapy has been reported as a useful treatment for large cell neuroendocrine carcinoma, but the effect of chemotherapy on it has not yet been fully investigated. Thus, we evaluated immunohistochemical data of the expression of drug-resistant proteins in large cell neuroendocrine carcinoma.Methods: We identified 10 large cell neuroendocrine carcinomas (1.2%) out of 850 primary lung cancers that had been surgically resected. We examined the immunohistochemical staining of three drug-resistant proteins, namely, P-glycoprotein, metallothionein and glutathione S-transferase-π to compare large cell neuroendocrine carcinoma with othe rhistological types of lung cancer.Results: The mean tumor cell positivity rates for P-glycoprotein, metallothionein and glutathione S-transferase-π in large cell neuroendocrine carcinoma were 0 %, 2.4 ±3.6% and 35.0±37.5%, respectively. The positivity rates for P-glycoprotein and glutathione S-transferase-π were significantly lower than those in adenocarcinoma (P=0.0003, P=0.0009). The positivity rate for glutathione S-transferase-π was also lower than that in squamous cell carcinoma (P=0.0387). These drug-resistant proteins showed similar expression pattern in both large cell neuroendocrine carcinoma and small cell carcinoma except glutathione S-transferase-π.Conclusion: Immunohistochemical expression of drug-resistant proteins in large cell neuroendocrine carcinoma was lower than that in adenocarcinoma and squamous cell carcinoma, and differences esist in drug-resistance between large cell neuroendocrine carcinoma and small cell carcinoma.     

Tubular function in diabetic children assessed by Tamm-Horsfall protein and glutathione S-transferase

In a previous study, we found urinary excretion of Tamm-Horsfall protein (THP) to be persistently decreased in 25% of patients during the first year after diagnosis of diabetes mellitus. We thus wanted to study another marker for distal tubular function, pi glutathione S-transferase (pi-GST) and compare this and THP with proximal tubular function evaluated with alpha-GST and alpha-1-microglobulin (HC) in patients with longer duration of diabetes. One hundred and eighty-four diabetic and 16 control children were studied with timed overnight urine collections. Median age was 14 years, and median age at diagnosis was 8 years. The urinary excretion of alpha- and pi-GST was significant lower in diabetic than control children. There were no differences in the excretion of HC and THP. Diabetic children with decreased alpha-GST had higher albumin excretion, HbA 1c levels, and longer diabetes duration but decreased THP excretion and cystatin-C clearance compared with those with normal excretion. In contrast, a decreased pi-GST or THP excretion was not associated with such differences. Diabetic children with increased HC excretion had increased HbA 1c levels. Diabetic children, before the stage of microalbuminuria, may have signs of both proximal and distal tubular dysfunction, which is related to diabetes duration and poor metabolic control. Alpha-GST and pi-GST seem to be more sensitive than other parameters studied.     

Performance of the BACTEC MGIT 960 compared with solid media for detection of Mycobacterium in Bangkok, Thailand

Controlled trials have demonstrated that liquid media culture (LMC) is superior to solid media culture for diagnosis of Mycobacterium tuberculosis (MTB), but there is limited evidence about its performance in resource-limited settings. We evaluated the performance of LMC in a demonstration project in Bangkok, Thailand. Sputum specimens from persons with suspected or clinically diagnosed tuberculosis were inoculated in parallel on solid (Lowenstein-Jensen [LJ]) and liquid (mycobacterial growth indicator tube [MGIT 960]) media. Biochemical tests identified isolates as MTB or nontuberculosis mycobacteria (NTM). Of 2566 specimens received from October 2004 to September 2006, 1355 (53%) were culture positive by MGIT compared with 1013 (39%) by LJ. Median time to growth for MGIT was significantly less than LJ: 11 versus 27 days. Of 1417 isolates detected by at least 1 media, 1255 (86%) were identified as MTB and 162 (11%) NTM. MGIT improved speed and sensitivity of MTB isolation and drug susceptibility testing, regardless of HIV status.     

五种结核病实验室检测方法对结核病诊断价值的效果评价

目的评价涂片法、BACTECMGIT960快速培养法、改良罗氏培养法、荧光定量PCR法和斑点免疫层析法在结核病实验室快速诊断方法中的作用和地位。方法对1260例结核病患者（结核病组）和100例非结核病患者（非结核病组）的各类标本采用涂片法、快速培养法、改良罗氏培养法、荧光定量PCR法进行检测,同时分离患者外周血血清进行结核抗体检测,并对这五种检测方法的结果进行分析比较。结果五种实验室检测方法对结核病组阳性标本和非结核病组阴性标本的检测结果差异均有统计学意义（χ2=466．31,χ2=216．14,P均〈0．05）。对于结核病组的涂阳和涂阴标本,快速培养法和荧光定量PCR法检测的灵敏度及准确度均高于其他三种方法,而涂片法、改良罗氏培养法、快速培养法的特异性均为100．0％,高于荧光定量PCR法和斑点免疫层析法;快速培养法的阳性检出率均较改良罗氏培养法高,差异均有统计学意义（χ2=3387．00,χ2=4233．00,P均〈0．05）,平均培养时间也较改良罗氏培养法短;但快速培养法与荧光定量PCR法的阳性检出率差异均无统计学意义（P均〉0．05）。结论BACTECMGIT960快速培养法和荧光定量PCR法是诊断结核病快速、有效的检测方法,其阳性检出率高,且能缩短培养时间,BACTECMGIT960快速检测系统还能进行快速药物敏感性试验,为结核病的快速诊断提供依据。     

Evaluation of different culture methods for the diagnosis of peritonitis in patients on continuous ambulatory peritoneal dialysis

A total of 170 continuous ambulatory peritoneal dialysis (CAPD) fluids were processed by various culture methods, including direct inoculation of the centrifuged sediment, inoculation into automated blood culture bottles, water lysis, Tween-80 incorporated blood agar, and Triton-X treatment of the specimen. Of 170 CAPD fluids, 127 showed the growth of bacteria/fungi. Sixty-three fluids showed growth by all methods, the water lysis alone detected 24 additional positive cultures, while Tween-80 blood agar and Triton-X yielded 30 additional positive cultures. A combination of water lysis, Tween-80 blood agar and Triton-X treatment of the CAPD fluid is recommended for diagnosis of CAPD peritonitis in resource-limited settings.     

MGIT sensitivity testing and genotyping of drug resistant Mycobacterium tuberculosis isolates from Mizoram,Northeast India

PurposeTuberculosis, a crucial infectious disease is still a health concern globally. India is among the countries with high MDR-TB burden. Currently, sputum smear microscopy using Ziehl Neelsen stain and GeneXpert are the only diagnostic means in Mizoram. This study was done to characterize local tuberculosis strains circulating in Mizoram.MethodsSputum was cultured using MGIT 960 and DST was performed for Streptomycin, Isoniazid, Rifampicin, Ethambutol and Pyrazinamide. GeneXpert test was done simultaneously. DNA was extracted using Trueprep AUTO v2, molbio diagnostics. Antibiotic Resistance Genes and LSP were amplified and sequenced.ResultsSer315Thr was the most common mutation in katG among MDR-TB isolates. GeneXpert probes A and D drop out upon sequencing showed L511P, H526Q and H526L mutation. The L511P and H526Q mutations were seen in new and treated cases. Discrepancy between MGIT 960 and GeneXpert were observed. LSP-PCR revealed that Indo-Oceanic, East-African Indian, Euro-American and Beijing lineages were found in Mizoram.ConclusionThis study provides mutation information on the resistant genotypes detected with GeneXpert as well as MGIT 960. It also provides information on the lineages of Mycobacterium tuberculosis circulating in the state. Utilization of sequencing technologies is essential in diagnostic laboratories to rule out discrepant results and as a cautionary measure to prevent wrong diagnosis and treatment.     

结核分枝杆菌快速培养药敏方法用于诊断老年矽肺结核

目的评价Bactec-MGIT 960对老年矽肺结核的诊断价值。方法Bactec-MGIT 960对46例老年矽肺结核患者痰标本进行结核杆菌快速培养和药物敏感试验,并与改良7H9法、改良L-J罗氏培养法作比较。结果Bactec-MGIT960、改良7H9法和L-J罗氏培养法培养平均报告时间分别为8.2、24.3、33.6d,培养阳性率分别为69.5%、65.2%、60.8%。Bactec-MGIT 960法药物敏感试验结果与其他检测方法相比,吻合率在90%以上。Bactec-MGIT 960培养、药敏报告时间为24d,较常规方法(J-L罗氏培养法)提前34d出报告。结论Bactec-MGIT 960快速培养结合改良7H9快速药敏试验有助于临床快速诊断。     

利用BACTEC 960分枝杆菌分析系统对分枝杆菌进行快速菌型鉴定方法的研究

目的:探索一种快速的分枝杆菌菌型鉴定方法。方法:用BACTEC 960分枝杆菌系统(960)和传统的改良罗氏培养基法(L-J法),对分枝杆菌标准菌株及临床分离菌株,同时进行菌型鉴定的对照研究,确定本法进行菌型鉴定的最佳药物浓度及具体优势。结果:本法进行快速菌型鉴定所需药物浓度为:噻吩-2-羧基肼(TCH)5.0μg/mL,对硝基苯甲酸(PNB)500μg/mL。进行快速菌型鉴定所需时间平均为6.7天,较L-J法平均提前23.3天。结论:本法明显缩短了分枝杆菌进行菌型鉴定的时间,为临床对分枝杆菌感染的菌型提供快速的诊断依据,并及时指导临床用药。     

BACTEC MGIT 960用于结核分枝杆菌直接药敏试验的研究

目的探讨BACTEC MGIT 960系统在结核分枝杆菌直接药敏试验的临床应用价值。方法对200株临床涂阳痰标本应用BACTEC MGIT 960系统进行一线抗结核药（链霉素、异烟肼、利福平、乙胺丁醇）结核分枝杆菌直接药敏试验,并与同步进行的BACTEC MGIT 960间接药敏试验及传统改良罗氏（L-J）比例法药敏试验进行比较,从结果报告时间和符合率等方面进行评价。统计学分析分别采用配对资料的t检验和Kappa检验。结果 BACTEC MGIT960直接药敏试验报告时间为（9.7±3.1）d,与BACTEC MGIT 960间接药敏试验报告时间（17.5±6.6）d比较差异有统计学意义（t=14.7,P〈0.01）,与L-J法报告时间（50.4±8.6）d比较差异有统计学意义（t=73.4,P〈0.01）;4种一线抗结核药物链霉素、异烟肼、利福平、乙胺丁醇药敏BACTEC MGIT 960直接法与BACTEC MGIT 960间接法药敏结果总符合率为97.3%,BACTEC MGIT 960直接法与L-J法药敏结果总符合率为96.2%。结论 BACTEC MGIT 960直接药敏试验快速、准确,可用于结核分枝杆菌的药物敏感性检测,利于耐药结核病的早期诊断和治疗。     

An in vitro assessment of the antineoplastic potential of 2H-1,3-Oxazine-2,6(3H)-dione (3-oxauracil), a novel pyrimidine

The pyrimidine (uracil) analogue 3-oxauracil (OU) previously had been shown to completely inhibit the growth of E. coli B and decrease by 96% the replication of herpes simplex virus type 2 when present in the culture fluid at a concentration of 10² µM. Limited in vivo studies in mice demonstrated antiviral effects without significant toxicity when given i.p. daily for two weeks at a concentration of 3.23 mg/kg. However, the antineoplastic properties of OU were unknown. We assessed the ability of OU to inhibit the proliferation of various human tumor cell lines (3 pancreatic, 1 colon, 1 neuroendocrine, and 1 lung) in an in vitro radiometric (Bactec) system. In the pancreatic lines (RWP-2, MiaPaCa-2, and PANC-1), the colon line (HT-29), the neuroendocrine line (COLO 320DM), and the lung cancer cell line (SK-MES-1), OU at a concentration of 10³ µM, produced a dramatic decrease in percent cell survival. When compared with cytotoxic drugs of choice for these tumor cells (gemcitabine, 5-fluorouracil, and adriamycin, respectively) a significantly higher concentration of OU was required usually to achieve comparable results with two exceptions. These were the HT-29 and the COLO 320DM cell lines. These results indicate OU has significant (p < 0.05) cytotoxic activity against pancreatic, colon, neuroendocrine, and nonsmall cell lung cancer lines, when compared to untreated control cultures. Additional in vivo testing of this potential antineoplastic agent is warranted.