弓形虫新基因表位疫苗免疫效果的观察

目的观察弓形虫新基因WX、WX2的表位疫苗对小鼠的保护作用。方法将昆明小鼠分成5组,分别用pcDNA3-W2b、pcDNA3-W4a、pcDNA3-W2b4a质粒及pcDNA3和NS,肌注3次,每次间隔2周。免疫完成后ELISA法检测血清抗体水平,取脾细胞用流式细胞仪检测CD4 与CD8 淋巴细胞比值,PCR检测肌肉组织中重组质粒。免疫后第3周,小鼠经腹腔注射弓形虫速殖子500个,观察发病情况和存活时间。30d后仍存活的小鼠,取组织匀浆后进行小鼠盲传。结果免疫后第3周,pcDNA3-W2b组小鼠血清抗体水平显著高于pcDNA3和NS对照组(P<0.05);用PCR法从pcDNA3-W2b、pcDNA3-W4a和pcDNA3-W2b4a质粒组小鼠肌肉组织中成功检测到各表位疫苗质粒,且各组小鼠脾脏CD4 与CD8 T淋巴细胞比值显著低于pcDNA3组和NS组(P<0.05)。pcDNA3-W2b、pcDNA3-W2b4a组小鼠存活时间与pcDNA3组及NS组比较明显延长(P<0.05)。结论弓形虫新基因WX、WX2表位疫苗能够诱导小鼠产生抗弓形虫感染保护性免疫,提示DNA类表位疫苗的研制可作为弓形虫疫苗研究的策略之一。     

日本血吸虫复合表位DNA质粒构建及鉴定

目的用GeneSOEing技术构建含日本血吸虫中国大陆株磷酸丙糖异构酶及副肌球蛋白T、B细胞表位的复合表位DNA质粒.方法将一个柔性的氨基酸“接头”插入真核表达质粒载体 pcDNA3.1中,构建pcDNA3.1-linker.PCR法扩增磷酸丙糖异构酶表位基因片段（T）.人工合成副肌球蛋白表位的基因片段,退火成双链（P）.分别将T、P片段克隆入改建的载体pcDNA3.1中linker的上游和下游,构建T- P融合基因;同时还将T、P片段分别克隆入linker的下游和上游,构建P-T融合基因.重组质粒分别转化E.coli XL1-blue,抽提质粒,酶切鉴定.结果两个目的基因片段分别按顺序克隆入真核表达质粒载体pcDNA3.1中,构建成复合表位DNA质粒.结论成功地构建了复合表位DNA质粒,为制备多价表位DNA疫苗奠定了基础.     

黄芪多糖、香菇多糖增强弓形虫wx2b4a表位疫苗免疫小鼠的保护作用

目的探讨黄芪多糖(Astragalan)、香菇多糖(Lentinan)增强弓形虫wx2b4a表位疫苗刺激机体产生免疫应答和保护免疫的效果。方法将黄芪多糖、香菇多糖分别与弓形虫wx2b4a表位疫苗混合肌注免疫小鼠,ELISA法检测小鼠血清中IgG抗体水平,pcDNA3-W2b4a刺激下培养各组小鼠脾脏淋巴细胞,ELISA法检测IL-2、IFN-γ分泌水平,CCK-8法检测免疫鼠脾细胞增殖活性,并观察其受到弓形虫攻击感染后的生存时间。结果各免疫组小鼠血清IgG抗体水平显著高于对照组(P<0.05),且pcDNA3-W2b4a+黄芪多糖组要高于pcDNA3-W2b4a+香菇多糖组(P<0.05);pcDNA3-W2b4a+黄芪多糖组、pcDNA3-W2b4a+香菇多糖组小鼠脾细胞IL-2、IFN-γ水平高于pcDNA3-W2b4a组(P<0.05);各免疫组T细胞增殖活性与对照组比较明显增强(P<0.05),且pcDNA3-W2b4a+香菇多糖组要高于pcDNA3-W2b4a+黄芪多糖组;小鼠攻击试验表明,pcDNA3-W2b4a+黄芪多糖组、pcDNA3-W2b4a+香菇多糖组小鼠存活时间明显长于对照组和pcDNA3-W2b4a组(P<0.05)。结论黄芪多糖、香菇多糖可增强弓形虫wx2b4a表位疫苗产生免疫应答,并显示较好的免疫保护效应。     

黄芪对弓形虫wx2b2a表位疫苗免疫小鼠后抗急性弓形虫感染的免疫调节作用北大核心CSCD

目的探讨黄芪对弓形虫wx2b2a表位疫苗免疫小鼠后抗急性弓形虫感染的免疫保护作用。方法将小鼠随机分成pcDNA3-W2b2a组、pcDNA3-W2b2a+黄芪治疗组、pcDNA3+黄芪治疗组、黄芪治疗组、pcDNA3及生理盐水对照组。将弓形虫pcDNA3-W2b2a肌注免疫pcDNA3-W2b2a组、pcDNA3-W2b2a+黄芪治疗组小鼠3次,末次免疫后4周,每组小鼠腹腔注射102个速殖子,感染后2d起,pcDNA3-W2b2a+黄芪治疗组、pcDNA3+黄芪治疗组及黄芪治疗组小鼠给予黄芪75mg/d灌胃治疗,连续用药7d,用ELISA法测定免疫前、末次免疫后4周、感染后6d小鼠血清IgG水平及免疫前、末次免疫后2周、感染后4、6、8d小鼠IFN-γ、IL-18水平,并观察弓形虫感染后小鼠的生存时间。结果 pcDNA3-W2b2a免疫小鼠后血清IgG抗体水平均高于其它组(P<0.05),末次免疫后4周,感染后第6dpcDNA3-W2b2a、pcDNA3-W2b2a+黄芪治疗组小鼠特异性IgG抗体水平无显著性差异(P>0.05);末次免疫后2周、感染后4d、6d、8dpcDNA3-W2b2a+黄芪治疗组小鼠血清IFN-γ水平分别高于其它组(P<0.05);感染后各组小鼠血清IL-18水平持续上升,但感染后8d,黄芪治疗后小鼠血清IL-18水平显著低于pcDNA3和生理盐水对照组(P<0.05);小鼠RH株速殖子感染后,pcDNA3-W2b2a+黄芪治疗组小鼠存活时间明显长于pcDNA3-W2b2a组、pcDNA3+黄芪治疗组及黄芪治疗组(P<0.05)。结论黄芪可增强弓形虫wx2b2a表位疫苗免疫小鼠后抗急性弓形虫感染的免疫调节作用。     

弓形虫pcDNA3-ROP2-p30-HSP70复合基因真核表达重组质粒的构建

目的构建弓形虫pcDNA3-ROP2-p30-HSP70真核表达重组质粒。方法根据HSP70基因序列,设计合成HSP70基因的引物,PCR扩增HSP70基因片段,克隆入pMD18-T载体,再经酶切、连接等,亚克隆至pcDNA3-ROP2-p30表达重组质粒中,并进行酶切、PCR和测序鉴定。结果 PCR扩增出长度为916bp的HSP70基因片段,将其克隆到pMD18-T中,成功亚克隆获得pcDNA3-ROP2-p30-HSP70表达重组质粒。测序结果显示,pcDNA3-ROP2-p30-HSP70表达重组质粒包含了HSP70蛋白基因完整序列。结论成功构建弓形虫pcDNA3-ROP2-p30-HSP70真核表达重组质粒,为下一步核酸疫苗的研究奠定了基础。     

弓形虫复合抗原基因P30-ROP2体外扩增、克隆及真核表达重组质粒的构建

目的　构建弓形虫RH株 pcDNA3.1 P30 ROP2 真核表达重组质粒,为进一步表达及 DNA疫苗的研制作准备。　方法　用PCR技术从弓形虫RH分离株的基因组DNA中扩增编码 P30基因片段和棒状体蛋白(ROP2)的基因片段,重组入 pUC18克隆载体,然后将 pUC18 P30 ROP2中的 P30 ROP2 外源基因片段经酶切、连接等反应,亚克隆入pcDNA3.1真核表达载体,再经含氨苄青霉素的LB培养基筛选、酶切及PCR鉴定。　结果　从弓形虫RH株基因组中扩增出特异的 P30、ROP2 片段,克隆成功 pUC18 P30 ROP2 重组质粒;经亚克隆、筛选鉴定获得了 pcDNA3. 1 P30 ROP2重组表达质粒。　结论　成功构建了弓形虫 pUC18 P30 ROP2重组克隆质粒,亚克隆成功 pcDNA3.1 P30 ROP2真核表达重组质粒,为下一步DNA疫苗的研究奠定了基础。     

弓形虫复合抗原基因P30-ROP2体外扩增、克隆及真核表达重组质粒的构建

目的 构建弓形虫RH株pcDNA3．1-P30-ROP2真核表达重组质粒，为进一步表达及DNA疫苗的研制作准备。方法 用PCR技术从弓形虫RH分离株的基因组DNA中扩增编码P30基因片段和棒状体蛋白(ROP2)的基因片段，重组人puC18克隆载体，然后将pUC18-P30-ROP2中的P30-ROP2外源基因片段经酶切、连接等反应，亚克隆入pcDNA3．1真核表达载体，再经含氨苄青霉素的LB培养基筛选、酶切及PCR鉴定。结果 从弓形虫RH株基因组中扩增m特异的P30、ROP2片段，克隆成功pUC18-P30-ROP2重组质粒；经亚克隆、筛选鉴定获得了pcDNA3．1-P30-ROP2重组表达质粒。结论 成功构建了弓形虫puC18P30-ROP2重组克隆质粒，亚克隆成功pcDNA3．1-P30-ROP2直核表达重组质粒，为下一步DNA疫苗的研究奠定了基础。     

尿路致病性大肠埃希菌Ⅰ型菌毛fimH基因真核表达载体pcDNA3.0-fimH的构建及鉴定

目的构建尿路致病性大肠埃希菌Ⅰ型菌毛的fimH基因真核表达载体,为尿路致病性大肠埃希菌的核酸疫苗研制奠定基础。方法通过PCR扩增尿路致病性大肠埃希菌临床分离株的fimH全基因序列,克隆至pMD19-T载体,PCR、酶切及测序鉴定后,将fimH基因片段克隆至真核表达载体pcDNA3.0,构建pcDNA3.0-fimH重组质粒,并进行PCR和酶切鉴定。结果 PCR扩增尿路致病性大肠埃希菌fimH基因片段为910 bp;构建的pcDNA3.0-fimH重组质粒经BamHⅠ和XhoⅠ双酶切,产生1个与fimH基因PCR产物大小一致的小片段和1个不同于pcDNA3.0-fimH重组质粒的大片段,表明fimH基因已成功插入pcDNA3.0质粒中。结论成功构建尿路致病性大肠埃希菌fimH基因真核表达载体pcDNA3.0-fimH。     

日本血吸虫多价DNA疫苗的构建及鉴定

目的构建含日本血吸虫中国大陆株磷酸丙糖异构酶(TPI)基因和日本血吸虫单克隆抗独特型抗体NP30H链CDR3区6倍重复表位基因(CDR3)6的多价DNA疫苗,并观察该融合基因在真核细胞中表达。方法设计合成连接肽(Gly4Ser)3基因的两条互补单链,退火成双链后克隆到真核表达载体pcDNA3.1,改建为pcDNA3.1-linker。分别将SjCTPIDNA片段及NP30的(CDR3)6DNA片段克隆到连接肽的上游或下游,构建pcDNA3.1-TPI-linker-(CDR3)6和pcD-NA3.1-(CDR3)6-linker-TPI2种多价疫苗。设计引物分别扩增TPI-linker-(CDR3)6和(CDR3)6-linker-TPI,再分别插入真核表达载体pEGFP-N1多克隆位点,绿色荧光蛋白基因的上游,重组质粒用脂质体导入真核细胞COS-7,观察插入基因在真核细胞的表达。结果经双酶切及测序鉴定证实多价疫苗pcDNA3.1-TPI-linker-(CDR3)6和pcDNA3.1-(CDR3)6-linker-TPI构建成功;构建的pEGFP-N1-TPI-linker-(CDR3)6和pEGFP-N1-(CDR3)6-linker-TPI在导入COS-7细胞后能成功表达。结论日本血吸虫TPI和NP30-(CDR3)6的多价DNA疫苗构建成功,且该融合基因能在真核细胞中表达。     

汉滩病毒S基因在Vero-E6细胞中的分段表达

目的　体外研究汉滩病毒 (HTNV)S基因及其 5’端、3’端表达的意义 ,为核蛋白T细胞表位的研究奠定基础。方法　设计 2套引物 ,用PCR方法从PBV2 2 0 -S2 2原核质粒中扩增出S基因全读码框 (37- 132 6bp)及S基因 5’端 (37-5 0 1bp) ,S基因 3’端 (5 0 2 - 132 6bp)用TA克隆将其克隆入 pcDNA3 1/V5 -His -TOPO载体中 ,成功构建 pcDNA3 1-S及pcDNA3 1-S -N、pcDNA3 1-S -C真核表达载体 ,并通过脂质体转染至Vero -E6细胞中 ,进行了瞬时表达。 结果　间接免疫荧光成功检测到 pcDNA3 1-S及pcDNA3 1-S -N、pcDNA3 1-S -C在Vero -E6细胞中的表达。 结论　pcDNA3 1-S及 pcDNA3 1-S -N、pcDNA3 1-S -C真核表达载体有较高的转染效率 ,目的基因能在宿主细胞中表达 ,有利于研究HTNV -S基因在T细胞表位研究中的意义。     

胰岛素瘤的解剖分布特点分析

目的胰岛素瘤是最常见的胰腺神经内分泌肿瘤，因其临床表现多样，导致诊断困难。影像学诊断尤其是超声内镜(EUS)在胰岛素瘤的诊断中起着重要作用，拥有较高的敏感性和特异性。本研究拟通过明确胰岛素瘤的解剖分布特点，以期有助于提高影像学的诊断准确率和降低漏诊率，尤其是在教育和培训实践中对于EUS的学习者更具有指导价值。 方法回顾性分析解放军总医院第一医学中心病案资料数据库1993年1月至2019年11月经外科手术、病理确诊为胰岛素瘤的患者的临床资料，检索方法采取搜索术后病理诊断为"胰岛素瘤"的病例，通过查阅病例的方法，提取出胰岛素瘤的大小和解剖分布等数据，进一步分析其特点。 结果共检索到确诊为胰岛素瘤的患者116例，其中，男45例、女71例，年龄13～76岁，平均年龄(44.4±14.85)岁。胰岛素瘤单发110例(94.8%)、多发6例(5.2%)。位置分布：头颈部46例(39.7%)，单发45例、多发1例；体尾部68例(58.6%)，单发65例、多发3例；全胰腺多发2例(1.7%)。病变大小特点：最大径0.4～3.4 cm，平均大小(1.53±0.58)cm。≤1 cm 29例、>1 cm而≤1.5 cm41例、>1.5 cm而≤2.0 cm28例，≤3 cm 15例，>3 cm 3例。年龄与肿瘤的大小相关，≤44岁患者肿瘤平均大小为(1.36±0.51)cm、>44岁患者肿瘤平均大小为(1.70±0.60)cm，P<0.05。头颈部的肿瘤大于体尾部的肿瘤，头颈部肿瘤平均大小(1.66±0.63)cm，体尾部(1.42±0.52)cm，P<0.05。 结论胰岛素瘤在胰腺体尾部较头颈部更好发；绝大多数单发，但可以全胰腺多发；多数小于1.5 cm，肿瘤的大小与患者年龄和肿瘤的解剖分布相关。     

Pathogenesis of carcinoma of the papilla of Vater

Most adenomas and carcinomas of the small intestine and extrahepatic bile ducts arise in the region of the papilla of Vater. In familial adenomatous polyposis (FAP) it is the main location for carcinomas after proctocolectomy. In many cases symptoms due to stenosis lead to diagnosis at an early tumor stage. In about 80%, curative intended resection is possible. Operability is the most relevant prognostic factor. Most ampullary carcinomas resp. carcinomas of the papilla of Vater develop from adenomatous or flat dysplastic precursor lesions. They can be sited in the ampulloduodenal part of the papilla of Vater, which is lined by intestinal mucosa. They also can develop in deeper parts of the ampulla, which are lined by pancreaticobiliary duct mucosa. Intestinal-type adenocarcinoma and pancreaticobiliary-type adenocarcinoma represent the main histological types of ampullary carcinoma. Furthermore, there exist unusual types and undifferentiated carcinomas. Many carcinomas of intestinal type express the immunohistochemical marker profile of intestinal mucosa (keratin 7?, keratin 20+, MUC2+). Carcinomas of pancreaticobiliary type usually show the immunohistochemical profile of pancreaticobiliary duct mucosa (keratin 7+, keratin 20?, MUC2?). Even poorly differentiated carcinomas, as well as unusual histological types, may conserve the marker profile of the mucosa they developed from. These findings underline the concept of histogenetically different carcinomas of the papilla of Vater which develop either from intestinal- or from pancreaticobiliary-type mucosa of the papilla of Vater. Molecular alterations in ampullary carcinomas are similar to those of colorectal as well as pancreatic carcinomas, although they appear at different frequencies. In future studies, molecular alterations in ampullary carcinomas should be correlated closely with the different histologic tumor types. Consequently, the histologic classification should reflect the histogenesis of ampullary tumors from the two different types of papillary mucosa.     

Demonstration of the mechanism of action of biguanides

Summary Palmitic acid oxidation in rat diaphragm homogenate is depressed by biguanide concentrations that are still incapable of inhibiting oxidative phosphorylation. Glucose oxidation is not directly effected by the same biguanide concentrations: however, the inhibitory effect of palmitic acid on glucose oxidation is partly removed by biguanides. Inhibition of fatty acid oxidation, which accounts for most of the metabolic effects caused by these drugs, can be regarded as the fundamental mechanism of action of biguanides. There is some evidence suggesting that these drugs might interact with carnitine, thus preventing long-chain fatty acids from being transported across the mitochondrial membrane to the site of oxidation. Traduzione a cura degli AA.     

Lack of correlation of degree of villous atrophy with severity of clinical presentation of coeliac disease

BACKGROUND AND AIM: Both the clinical presentation and the degree of mucosal damage in coeliac disease vary greatly. In view of conflicting information as to whether the mode of presentation correlates with the degree of villous atrophy, we reviewed a large cohort of patients with coeliac disease. PATIENTS AND METHODS: We correlated mode of presentation (classical, diarrhoea predominant or atypical/silent) with histology of duodenal biopsies and examined their trends over time. RESULTS: The cohort consisted of 499 adults, mean age 44.1 years, 68% females. The majority had silent coeliac disease (56%) and total villous atrophy (65%). There was no correlation of mode of presentation with the degree of villous atrophy (p=0.25). Sixty-eight percent of females and 58% of males had a severe villous atrophy (p=0.052). There was a significant trend over time for a greater proportion of patients presenting as atypical/silent coeliac disease and having partial villous atrophy, though the majority still had total villous atrophy. CONCLUSIONS: Among our patients the degree of villous atrophy in duodenal biopsies did not correlate with the mode of presentation, indicating that factors other than the degree of villous atrophy must account for diarrhoea in coeliac disease.     

血吸虫童虫生长发育及其机制的研究进展

血吸虫童虫是宿主免疫系统攻击的重要靶标,包括皮肤型、肺型和肝门型童虫。宿主分子对童虫生长发育具有重要作用。童虫生长发育机制包括免疫调节、信号转导、性别发育及凋亡等。肌动蛋白、组织蛋白酶、烯醇化酶和葡萄糖基转移酶等分子为血吸虫童虫生长发育的重要分子。本文对血吸虫童虫生长发育及其机制的研究进展做一综述。     

氯硝柳胺悬浮剂的毒性评价

目的评价氯硝柳胺悬浮剂的毒性，为现场大规模应用灭螺提供依据。方法按照中华人民共和国国家标准GB 15670-1995《农药登记毒理学试验方法》和鱼类毒性试验方法进行。结果经口、经皮肤的LDso雌、雄性大鼠均>5 000 mg/kg，经呼吸道的LCso雌、雄性大鼠均>5 000mg/m3，该药经口、经皮肤、经呼吸道毒性均属微毒类药物；兔眼用药后，观察期内无不良反应，对眼无刺激性；皮肤用药后对皮肤无刺激性。与氯硝柳胺原药、氯硝柳胺乙醇胺盐原药和氯硝柳胺乙醇胺盐可湿性粉剂相比，氯硝柳胺悬浮剂对鱼急性毒性最低。结论氯硝柳胺悬浮剂属微毒类药物，对鱼的毒性低于其乙醇胺盐可湿性粉剂，适合于现场应用。     

124例耐多药结核分枝杆菌基因突变特征分析

目的对临床分离的耐多药结核分枝杆菌相关基因的突变特征进行分析。方法对124例耐多药结核分枝杆菌以及50株敏感株的耐药相关基因(包括异烟肼inh A、kat G、oxyR-ahp C间隔区以及利福平rpo B)进行序列测定,分析其基因突变情况。结果异烟肼耐药inh A基因突变率为14.5%;kat G基因突变率为70.2%(87/124),主要位于315位;oxyR-ahp C间隔区突变率为15.3%;inh A、kat G两种基因同时突变率75.0%,三种基因同时突变率为89.5%。利福平rpo B基因突变的检出率高达95.2%,突变主要发生在531、526、516位点。结论我省耐多药菌异烟肼耐药相关基因最常见突变为kat G 315、inh A C-T(-15)、axyR-ahp C间隔区(-10)C-T,利福平为rpo B531、526、516。结合MDR-TB耐药相关基因的特征分析,可以建立一种快速、准确、特异的适合于我省的检测结核菌耐多药性的新方法。     

Assessment of quality of life of parents of children with juvenile chronic arthritis

The aim of the study was to assess the quality of life (QOL) and the psychological status of parents of children with juvenile chronic arthritis (JCA). The QOL, anxiety and depression of the parents of 28 children with JCA were evaluated and compared to those of the parents of 28 healthy children. Mothers of JCA children and mothers of healthy children reported similar QOL. The reported anxiety and depression levels were similar for mothers and fathers in both groups. The parents of children with pauciarticular-type JCA reported lower QOL and higher levels of anxiety and depression than the parents of children with other types, namely polyarticular and systemic JCA. These findings may be explained by the fact that the pauciarticular patients had shorter disease duration and were less frequently seen in the outpatient clinic. The QOL of mothers of children with JCA was found to be slightly impaired in the group of children with pauciarticular JCA. Future larger studies are needed to confirm these results, as the number of subjects in the three groups was rather low. Received: 26 September 2001 / Accepted: 8 February 2002     

Numerical Simulation of the Effect of Rate of Change of Glucose on Measurement Error of Continuous Glucose Monitors

Background

A 5-day in-patient study designed to assess the accuracy of the FreeStyle Navigator® Continuous Glucose Monitoring System revealed that the level of accuracy of the continuous sensor measurements was dependent on the rate of glucose change. When the absolute rate of change was less than 1 mg•dl⁻¹•min⁻¹ (75% of the time), the median absolute relative difference (ARD) was 8.5%, with 85% of all points falling within the A zone of the Clarke error grid. When the absolute rate of change was greater than 2 mg•dl⁻¹•min⁻¹ (8% of the time), the median ARD was 17.5%, with 59% of all points falling within the Clarke A zone.

Method

Numerical simulations were performed to investigate effects of the rate of change of glucose on sensor measurement error. This approach enabled physiologically relevant distributions of glucose values to be reordered to explore the effect of different glucose rate-of-change distributions on apparent sensor accuracy.

Results

The physiological lag between blood and interstitial fluid glucose levels is sufficient to account for the observed difference in sensor accuracy between periods of stable glucose and periods of rapidly changing glucose.

Conclusions

The role of physiological lag on the apparent decrease in sensor accuracy at high glucose rates of change has implications for clinical study design, regulatory review of continuous glucose sensors, and development of performance standards for this new technology. This work demonstrates the difficulty in comparing accuracy measures between different clinical studies and highlights the need for studies to include both relevant glucose distributions and relevant glucose rate-of-change distributions.     

Study of constancy of hydrogen-consuming flora of human colon

The constancy of the hydrogen consuming flora of the human colon was studied in 15 healthy subjects via two measurements obtained 18 to 36 months apart. Hydrogen disappearance rate and the major products of H₂-consuming bacteria, methane and sulfide, were measured during incubation of fecal homogenates with excess hydrogen and sulfate. In 11/15, the hydrogen consumption rate and the predominant hydrogen-consuming pathway (methanogenesis, sulfate reduction, or neither) remained constant. However, major shifts in these pathways were observed in four subjects, with two losing and two gaining the ability to produce methane. Methanogenesis was associated with the highest hydrogen consumption rate. This study demonstrates that clinically unrecognizable, major alterations of the colonic flora occur in healthy subjects. Understanding of the factors responsible for these alterations might allow for therapeutic manipulation of the colonic flora.Supported in part by the Department of Veterans Affairs and NIDDKD RO1 DK 13309-25.