The Mitochondrial Genome And Human Mitochondrial Diseases

To date, more than 100 point mutations and several hundreds of structural rearrangements of mitochondrial DNA (mtDNA) are known too be connected with characteristic neuromuscular and other mitochondrial syndromes varying from those causing death at the neonatal stage to diseases with late ages of onset. The immediate cause of mitochondrial disorders is a defective oxidative phosphorylation. Wide phenotypic variation and the heteroplasmy phenomenon, which some authors include in mutation load, are characteristic of human mitochondrial diseases. As the numbers of cases identified and pedigrees described increase, data on the genotype-phenotype interaction and the structure and frequency of pathogenic and conditionally pathogenic mtDNA mutations in human populations are rapidly accumulated. The data on the genetics and epidemiology of mitochondrial diseases are not only important for differential diagnosis and genetic counseling. Since both neutral and mildly pathogenic mutations of mtDNA are progressively accumulated in maternal phyletic lines, molecular analysis of these mutations permits not only reconstruction of the genealogical tree of modern humans, but also estimation of the role that these mutations play in natural selection.     

Population pharmacokinetics of enfuvirtide in HIV-1-infected pediatric patients over 48 weeks of treatment

The objective of this study was to characterize the population pharmacokinetics of enfuvirtide in HIV-1-infected children and adolescents. HIV-infected patients received combination antiretroviral therapy, including enfuvirtide 2.0 mg/kg subcutaneously, twice daily. Serial and trough blood samples were collected up to 48 weeks. NONMEM was used for population pharmacokinetic analysis. Enfuvirtide exposure was calculated from individual parameter estimates derived from the final model. A total of 218 samples from 43 patients were included in the analysis. Enfuvirtide plasma concentration-time data were described by a 1-compartment model with first-order absorption and elimination. The addition of each subject's actual body weight as a covariate affected CL/F but not V/F or K(a). The population CL/F, V/F, and K(a) for a 33-kg reference patient was 1.31 L/h, 2.31 L, and 0.105 h(-1), respectively. The final model was CL/F (L/h) = 1.31 . (body weight/33 [kg])(0.721). Age did not affect enfuvirtide exposure. These results confirm the appropriateness of body weight-based pediatric enfuvirtide dosing.     

Antibodies to hepatitis C virus in autologous blood donors

Hepatitis C virus (HCV) is the major cause of posttransfusion hepatitis. Two anti-HCV enzyme immunoassay (EIA) kits and one recombinant immunoblot assay (RIBA) were used to test serum samples of 1476 donations from 692 autologous blood donors to assess the prevalence of anti-HCV and its relationship to transfusion history. Of all autologous blood donations, 23 (1.6%) reacted when tested with one EIA kit and 29 (2.0%) reacted when tested by the other EIA kit. Of the autologous donors, 12 (1.78%) reacted by the first EIA kit and 14 (2.02%) by the second. Discrepancies in the EIA results from different donations by the same donor were seen in seven donors. The RIBA was positive or indeterminate in 33 percent of the EIA-reactive donations and in 41 percent of EIA-reactive donors. All RIBA-positive and -indeterminate samples reacted with both EIA kits. There was no significant difference in the EIA-reactive rates of autologous and first-time homologous blood donors. Previously transfused autologous blood donors had a higher anti-HCV EIA-reactive rate than nontransfused autologous donors, but the difference was not significant. In regard to hepatitis C, the use of autologous blood for homologous transfusion appears to be as safe as the use of blood from first-time homologous donors. Universal testing of previously transfused patients for hepatitis C appears premature at this time. Discrepant anti-HCV EIA results from different donations from the same individual have implications regarding donor deferral.     

NEW INVESTIGATOR AWARD FINALISTSNIA0001Induction of differentiation in human preadipocytes may contribute to adipogenic effect of human adenovirus Ad-36

Human adenovirus Ad-36 causes adiposity in animal models and shows association with human obesity. The mechanism involved is unknown. We previously reported that Ad-36 enhances differentiation of 3T3-L1 preadipocytes and E4orf-1 gene of the virus is responsible for the adipogenic effect in the rodent cell line. We undertook a three-step approach to investigate the role of preadipocyte differentiation in adipogenic effect of Ad-36. First, we showed that the viral mRNA is expressed in adipose-derived stem cells (ASC) of animals experimentally infected with Ad-36. Infection of rats with Ad-36 resulted in increased epididymal fat pad weight and the expression of Ad-36 E4orf-1 mRNA was detected in ASC isolated from the fat pads. Next, we determined if humans naturally infected with Ad-36 will show greater preadipocyte differentiation. Subcutaneous adipose-tissue samples from 33 Pima Indian subjects were screened by nested-PCR specific for Ad-36 DNA. Nine subjects (27%) had Ad-36 DNA. A blinded comparison of their ASC showed greater differentiation to adipocytes for the Ad-36 DNA positive subjects ( P =  0.06) compared to the Ad-36 DNA negative group. Finally, we used a direct approach. Human-ASC when infected with Ad-36 showed spontaneous replication, differentiation, and lipid accumulation, which was significantly greater than the uninfected controls ( P  < 0.01). Ad-36 induced lipid accumulation in human-ASC increased in response to the viral load and the lipogenic response was observed regardless of the donor gender and over an age range of 22–57 years. These results suggest that ability of Ad-36 to induce preadipocyte differentiation may play a role in human adiposity.     

Anti-inflammatory activity of the leaf extacts of Gendarussa vulgaris Nees

Objective

To evaluate the anti-inflammatory property of the leaf exacts of Gendarussa vulgaris (G. vulgaris) Nees.

Methods

G. vulgaris Nees of the family Apocynaceae is a medium sized tree grown in semishade or no shade and is common in the Ernad and Nilambur taluks of Kerala.Various parts of this plant have been used in the treatment of ulcers, sores, inflammation, dyspepsia, healing of wounds, etc. The present study aimed at the evaluation of anti-inflammatory property of the aqueous and alcoholic extracts of the leaves by both in vitro and in vivo methods. In vitro method was estimated by human red blood cell membrane stabilisation (HRBC) method and in vivo method was estimated on the carrageenan induced paw oedima.

Results

Both the methods showed significant anti-inflammatory property of the different extracts tested.

Conclusions

The alcoholic extract at a concentration of 300 mg/mL showed potent activity on comparing with the standard drug diclofenac sodium.     

腹腔镜膀胱癌根治加回肠膀胱术

目的:总结腹腔镜下膀胱癌根治加回肠膀胱术的手术方法及临床疗效。方法:2003年6月～2007年5月共行25例腹腔镜下根治性全膀胱切除、双侧盆腔淋巴结清扫加回肠膀胱术,患者平均年龄68岁,全膀胱切除和盆腔淋巴结清扫均在腹腔镜下完成,标本自下腹部小切口取出后,体外切取末端回肠10～15cm,近端闭合并与双侧输尿管吻合,远端造口于右下腹壁。结果:所有手术均顺利完成,手术时间210～320min,平均270min。术中出血220～1000ml,平均460ml。平均每例清扫淋巴结数10个,淋巴结阳性率16.2%,手术切缘均阴性。术后3～5天肠道功能恢复,1例因粘连性肠梗阻于术后1周再行手术探查松解粘连。术后2～3周拔除单J管,无肠漏及尿漏并发症发生。随访2～30个月,1例死于原发病转移,无腹壁造口狭窄发生,3例术后B超或造影显示单侧轻度肾积水和轻度输尿管扩张。结论:腹腔镜膀胱癌根治术具有创伤小,恢复快等优点,但手术难度较大,手术技术要求较高。回肠膀胱术手术操作相对简单,并发症少,可作为腹腔镜膀胱癌根治术后尿流改道可选方式之一。     

Cyclin-dependent kinase inhibitor Dinaciclib (SCH727965) inhibits pancreatic cancer growth and progression in murine xenograft models

Pancreatic cancer is one of the most lethal of human malignancies, and potent therapeutic options are lacking. Inhibition of cell cycle progression through pharmacological blockade of cyclin-dependent kinases (CDK) has been suggested as a potential treatment option for human cancers with deregulated cell cycle control. Dinaciclib (SCH727965) is a novel small molecule multi-CDK inhibitor with low nanomolar potency against CDK1, CDK2, CDK5 and CDK9 that has shown favorable toxicity and efficacy in preliminary mouse experiments, and has been well tolerated in Phase I clinical trials. In the current study, the therapeutic efficacy of SCH727965 on human pancreatic cancer cells was tested using in vitro and in vivo model systems. Treatment with SCH727965 significantly reduced in vitro cell growth, motility and colony formation in soft agar of MIAPaCa-2 and Pa20C cells. These phenotypic changes were accompanied by marked reduction of phosphorylation of Retinoblastoma (Rb) and reduced activation of RalA. Single agent therapy with SCH727965 (40 mg/kg i.p. twice weekly) for 4 weeks significantly reduced subcutaneous tumor growth in 10/10 (100%) of tested low-passage human pancreatic cancer xenografts. Treatment of low passage pancreatic cancer xenografts with a combination of SCH727965 and gemcitabine was significantly more effective than either agent alone. Gene Set Enrichment Analysis identified overrepresentation of the Notch and Transforming Growth Factor-β (TGFβ) signaling pathways in the xenografts least responsive to SCH727965 treatment. Treatment with the cyclin-dependent kinase inhibitor SCH727965 alone or in combination is a highly promising novel experimental therapeutic strategy against pancreatic cancer.Key words: pancreatic cancer, xenograft mouse models, cyclin-dependent kinases, SCH727965, dinaciclib, cell cycle, translational research