细菌影响泌尿系结石形成的作用机制及其化学基础*

人体内影响泌尿系结石形成的细菌有2类:一类诱发尿石形成,主要是通过分解尿素使尿液pH升高、加重尿路感染、降低尿石抑制剂浓度、破坏尿路粘膜酸性粘多糖保护层从而促进晶体滞留;另一类抑制尿石的形成,这些细菌(主要为食草酸杆菌、乳酸杆菌和粪肠球菌等草酸分解菌)参与外源性草酸代谢,降低尿草酸浓度。探讨了该领域所面临的问题和将来的发展方向。     

细菌影响泌尿系结石形成的作用机制及其化学基础

人体内影响泌尿系结石形成的细菌有2类：一类诱发尿石形成,主要是通过分解尿素使尿液pH升高、加重尿路感染、降低尿石抑制剂浓度、破坏尿路粘膜酸性粘多糖保护层从而促进晶体滞留;另一类抑制尿石的形成,这些细菌（主要为食草酸杆菌、乳酸杆菌和粪肠球菌等草酸分解菌）参与外源性草酸代谢,降低尿草酸浓度。探讨了该领域所面临的问题和将来的发展方向。     

乳酸菌在疾病防治和人体保健中的应用研究进展

肠道微生物在人体健康方面起着重要的作用,良好的肠道微生态环境是维持人体健康的重要因素,随着对肠道微生物越来越多的关注和研究,人们发现益生菌在肠道菌群和宿主健康之间有着复杂的关系。大量的研究发现,乳酸菌作为益生菌在人体肠道微生态平衡、疾病防治和保健中起着至关重要的作用。综述了乳酸菌对人体微生态环境的益生功能,并对乳酸菌和人体微生态环境之间的相互影响和关系,以及乳酸菌对一些常见人体疾病的预防和治疗作用的研究进展。     

271例新疆南部维吾尔族患者尿结石成分分析与代谢评价

目的:探讨新疆南部维吾尔族泌尿系结石患者结石成分与代谢异常的关系.方法:分析271例泌尿系结石患者的结石成分及其中177例24h尿分析,并将二者结合作初步评价.结果:草酸钙结石214例(78.9%),感染性结石7例(2.6%),尿酸结石29例(10.7%),磷酸盐结石17例(6.3%),胱氨酸结石4例(1.5%).177例24 h尿分析结果患者中代谢异常129例(72.9%),其中高钙尿症40例(22.6%),高尿酸尿症62例(35.0%),高草酸尿症43例(24.3%),高尿磷71例(40.1%),低枸橼酸尿症117例(66.1%),低尿镁症59例(33.3%),24h尿量＜2000ml者72例(40.7%),高胱氨酸尿症2例(1.1%).结论:结石成分及患者的代谢评价对泌尿系结石的成因、治疗和预防有重要的临床意义.     

胆结石患者应注意怎样饮食?

肾结石中１１～８４％是草酸钙结石，５％～１０％是尿酸结石，此外还有胱胺酸结石、磷酸镁胺结石等。就大多数结石而言，采取适当饮食有利于抑制结石形成。①饮食应少吃肉类、少吃盐，有利于抑制结石形成。②少吃富含草酸的食物：如菠菜、大黄、豌豆、巧克力、茶等。③增加含钙食品：含钙食品进入肠道后，其中钙可和肠道中草酸结合成草酸钙而排出体外，从而阻抑了肠道草酸的重吸收，使血中草酸浓度低，从而抑制草酸钙结石形成。④多饮水、多运动、尽量少饮酒。肾结石患者应注意怎样饮食?     

菌株DM8320安全评价及其发酵乳对大鼠肾结石形成的影响

目的 对具有降解草酸能力的菌株DM8320进行初步安全性评价并观察其发酵乳对肾结石模型大鼠的影响.方法 通过检测DM8320的质粒,细菌易位试验以及急性毒性试验对DM8320进行初步安全性评价.构建大鼠肾结石模型的同时灌胃目的菌株的牛奶发酵乳,实验第29天,收集24 h尿液并检测尿液中钙离子、草酸的含量.取大鼠左肾制作石蜡切片,观察各个实验组结石发生情况.结果 菌株DM8320中不含质粒,未发生细菌易位现象,不具有毒性.DM8320发酵乳可降低肾结石模型大鼠尿中的草酸和钙离子含量.观察各组大鼠肾脏石蜡切片,结石组中结石含量最多,低剂量组次之,高剂量组肾结石结晶含量较少.结论 菌株DM8320具有一定的安全性,其发酵乳对Wistar大鼠肾结石的形成具有一定的抑制作用.     

高效降解草酸乳酸菌的筛选

尿路结石70%~80%主要由草酸钙结晶构成。人体内的草酸一般通过肠道内微生物降解,经由粪便排出或在泌尿道吸收由尿液排出。本研究对市场上商品化的发酵乳制品、饮料和药品中的乳酸菌进行分离,得到37株菌,包括嗜热链球菌、保加利亚乳杆菌、干酪乳杆菌、鼠李糖乳杆菌、植物乳杆菌、嗜酸乳杆菌、动物双歧杆菌、长双歧杆菌、粪肠球菌、屎肠球菌和乳球菌,并检测这些菌株降解草酸的能力。结果提示,乳酸菌在体外能够有效的降低培养物中的草酸浓度,并筛选出了具有高效降解草酸能力的乳酸菌菌株。有望成为尿石症预防的新措施。     

三金排石汤对特发性钙结石患者24小时尿成石危险因素水平的影响

目的:分析三金排石汤对特发性钙结石患者24小时尿成石危险因素水平的影响,探讨其用于预防手术取石后的特发性钙结石患者结石复发的临床价值。方法:选择2009年9月~2013年9月入住我院的经皮肾镜取石术或输尿管镜取石术治疗的特发性钙结石患者100例,前瞻性将其随机分为治疗组和观察组,两组各50例。治疗组予三金排石汤每日一剂分两次煎服,观察组予正常饮食,测定和比较两组患者治疗前和治疗1个月后的24小时尿成石危险因素水平。结果:治疗1个月后,观察组24小时尿成石危险因素水平与治疗前比较差异均无统计学意义(P0.05);治疗组24小时尿量较治疗前显著增加,尿pH值、尿枸橼酸含量明显升高,尿钙显著降低,差异均有统计学意义(P0.05),但尿钠、尿镁、尿磷、尿尿酸及尿草酸水平与治疗前比较差异均无统计学意义(P0.05);与观察组比较,治疗组24小时尿量明显增加,尿pH值、尿枸橼酸含量显著升高,尿钙水平明显降低,差异均有统计学意义(P0.05),但两组尿钠、尿镁、尿磷、尿尿酸及尿草酸水平比较差异均无统计学意义(P0.05)。结论:三金排石汤治疗手术取石后特发性钙结石患者能够显著增加其24小时尿量及尿枸橼酸含量,并减少尿钙含量,抑制结石形成,这可能有助于降低特发性钙结石患者手术取石后的复发风险,值得临床研究和推广。     

泌尿系统结石合并感染患者尿路病原菌分布及危险因素分析

目的分析泌尿系统结石合并感染患者尿路病原菌分布及其危险因素,为后续研究提供参考。方法收集2016年1月至2019年1月我院诊治的430例泌尿系统结石患者为研究对象,根据患者是否发生感染分为感染组(n=34)和非感染组(n=396)。分析两组患者的临床特征和感染组患者病原菌分布情况,同时对影响患者感染的高危因素进行Logistic回归分析。结果感染组患者共计检出84株病原菌,其中革兰阳性球菌20株(23.81%),革兰阴性杆菌60株(71.43%),其他4株(4.76%)。两组患者白细胞水平、尿路梗阻情况、血肌酐水平、尿pH7.0比例、血尿素氮水平、合并肾积水情况、结石位置、结石直径、抗菌药物使用种类差异均有统计学意义(均P0.05)。合并肾积水、尿路梗阻、白细胞计数(≤10×10~9个/L)、尿pH(7.0)、血尿素氮(≥7.15 mmol/L)、结石位置(上尿路)、抗菌药物使用种类(≥3种)均为泌尿系统结石合并尿路感染的高危因素,而血肌酐水平,结石直径与泌尿系统结石合并尿路感染无明显相关性。结论泌尿系统结石患者易并发尿路感染,其病原菌以革兰阴性杆菌为主。导致尿路感染的因素较多,临床上应提前制定预防措施,降低结石患者尿路感染发生率。     

2型糖尿病患者泌尿系结石形成的相关影响因素分析

目的:探讨2型糖尿病(T2DM)患者泌尿系结石形成的相关影响因素。方法:根据是否合并泌尿系结石,将106例糖尿病患者分为观察组和对照组,每组53例,比较两组患者临床资料及生化指标的差异,并采用多因素回归分析研究2型糖尿病与泌尿系结石的相关关系。结果:观察组和对照组患者的年龄、性别、收缩压(SBP)、舒张压(DBP)、总胆固醇(TC)、空腹血糖(FBG)、餐后2 h血糖(2h FBG)、糖化血红蛋白(Hb A1C)等资料比较差异均无统计学意义(P0.05),而两组患者在体重指数(BMI)、甘油三酯(TG)、尿p H值、胰岛素抵抗指数(HOMA-IR)、血尿酸(SUA)、24小时尿酸(TUA)水平比较差异具具有统计学差异(P0.05),多因素Logistic回归分析显示血尿酸、尿p H值和HOMA-IR为2型糖尿病患者泌尿系结石形成的重要危险因素(P0.05)。结论:高尿酸血症、高甘油三酯血症、高尿酸排泄、胰岛素抵抗、肥胖或超重等因素促进了泌尿系结石的形成,其中血尿酸、尿p H值、HOMA-IR是2型糖尿病患者合并泌尿系结石形成的独立危险因素。     

Electrokinetic energy conversion studies of urine-oxalic acid systems across urinary bladder membrane.

Electrokinetic studies of urine-oxalic acid systems with increasing concentration of oxalic acid in urine have been carried out across urinary bladder membranes. It has been found that electro-osmotic flux and streaming current decrease with increase in concentration of oxalic acid in urine while hydrodynamic flux and streaming potential increase with increase in concentration. Kinetic energy term (alpha 1) and polarizability term (alpha 2) have been computed for these systems and it has been found that polarizability decreases much faster with increase in concentration of oxalic acid in urine. Electrokinetic energy conversion of these systems have been computed and it has been found that electrokinetic energy conversion is maximum for urine and it decreases with increase in concentration of oxalic acid in urine. Poor energy conversion may lead to sluggish flushing action which may ultimately lead to formation of urinary calculi in the bladder and so present study may be of some use in predicting electrophysiology of the bladder.     

Simultaneous detection of 35S- and 32P-labeled proteins on electrophoretic gels

A new method for the determination of oxalic acid in urine, which does not require isolation of oxalic acid, was developed by derivatizing oxalic acid and separating and quantitating the product by automated liquid chromatography. Oxalic acid in urine was reacted with o-phenylenediamine to form the strongly uv-absorbing compound 2,3-dihydroxyquinoxaline. Isolation and quantitation of this derivative were accomplished using a reverse-phase C₈ column, 5% methanol in 0.1 m ammonium acetate buffer (pH 6.6) as eluant, and absorption at 314 nm. The method was linear from 1 to 151 μg oxalic acid/ml of sample and the conversion of oxalic acid to the dihydroxyquinoxaline over this concentration range was 94.9%. The precision of duplicates averaged ±1.1%. Analyses of urine before and after treatment with oxalate decarboxylase were employed to differentiate actual urinary oxalic acid from oxalogenic compounds. Under the conditions employed, no urine was found to contain inhibitors of oxalate decarboxylase. No significant contribution to the method was found in a study of 19 potentially interfering urinary constituents. Levels of oxalic acid found in 27 urine samples from patients by this method averaged 71% of levels found using an earlier colorimetric method.     

Specific and rapid assay of urinary oxalic acid using high-performance liquid chromatography

A high-performance liquid chromatographic (HPLC) method was developed to determine the levels of oxalic acid in the urine. This acid was extracted from urine with tri-n-butyl phosphate and converted into the fluorescent derivative by esterification with 9-anthryldiazomethane (ADAM). The reaction mixture containing the oxalic acid derivative can be directly chromatographed on HPLC using octadecylsilane reverse-phase column monitoring with a fluorophotometric detector. A linear relationship was observed in the range from 1 to 100 micrograms/ml of standard oxalic acid dissolved in saline. Disease-free Japanese adults excrete 23.8 +/- 9.0 mg (mean +/- SD) of oxalic acid per day. This method should prove valuable for routine measurements of urinary oxalic acid as it is accurate, simple, and specific.     

Interaction of P-glycoprotein with a hydrophobic component of rat urine.

The presence of an endogenous P-glycoprotein substrate in rat urine was examined by testing the ability of a hydrophobic extract to reverse multidrug resistance in CHO cells and to inhibit [3H]azidopine photolabelling. The accumulation of several hydrophobic drugs and dyes, known to be transported by P-glycoprotein, was dramatically enhanced in multidrug-resistant CHO cells (CHRC5) by a component contained in a hydrophobic extract prepared from rat urine by octadecyl (C18) reverse phase chromatography. The biological action of this urinary component involves a direct interaction with P-glycoprotein since it blocked photolabelling of the protein with [3H]azidopine. The effective concentration of the substance required to enhance drug accumulation and inhibit photolabelling was similar and within the range of its urinary content. These results suggest that a hydrophobic substance in urine may be an endogenous substrate of kidney P-glycoprotein.     

大蒜素通过抑制OPN表达和NF‑κB通路活化对大鼠肾结石形成的作用研究

大蒜素可改善草酸诱导的肾小管上皮细胞损伤,以肾结石大鼠为研究对象,探讨大蒜素对肾结石大鼠的作用及其可能的机制。采用1%乙二醇+2%氯化铵混合液灌胃造模（空白组除外）,分别灌胃大蒜素7.5 mg·kg^-1（低剂量大蒜素组）、15 mg·kg^-1（高剂量大蒜素组）、胃枸橼酸氢钾钠颗粒0.6 g·kg^-1（阳性对照组）,其余组灌胃0.9%氯化钠溶液（空白组）,检测各组大鼠与肾结石疾病相关的指标。与空白组相比,模型组大鼠肾指数、肌酐（creatinine,Cr）、血清尿素氮（blood urea nitrogen,BUN）水平和天冬氨酸转氨酶（aspartate aminotransferase,AST）、谷丙转氨酶（alanine aminotransferase,ALT）活性及24 h尿量、尿液中草酸、钙和磷含量显著升高（P<0.05）,草酸钙结晶评分显著升高（P<0.05）,镁含量显著降低（P<0.05）,骨桥蛋白（osteopontin,OPN）表达显著升高（P<0.05）,核因子κB（nuclear factor-κB,NF-κB）通路活化;与模型组相比,低剂量大蒜素组、高剂量大蒜素组和阳性对照组大鼠肾指数、Cr、BUN水平和AST、ALT活性、24 h尿量、尿液中草酸、钙和磷含量显著降低（P<0.05）,草酸钙结晶评分显著降低（P<0.05）,镁含量显著升高（P<0.05）,OPN表达显著降低（P<0.05）,NF?κB通路被抑制。结果表明,大蒜素通过改善大鼠肾功能指标、抑制骨桥蛋白表达和NF?κB通路活化进而抑制肾结石形成。     

CD46 (membrane cofactor protein) acts as a human epithelial cell receptor for internalization of opsonized uropathogenic Escherichia coli

Escherichia coli is a common urinary pathogen whose uptake into epithelial cells is mediated by attachment through type 1 fimbriae. In this study, we show by using using human urinary tract epithelial cells that maximal internalization of E. coli is achieved only when bacteria are opsonized with complement. The concentrations of complement proteins in the urine rise sufficiently during infection to allow bacterial opsonization. The complement regulatory protein, CD46 (membrane cofactor protein), acts in cohort with fimbrial adhesion to promote the uptake of pathogenic E. coli. This uptake is inhibited by RNA interference to lower the expression of CD46 and by soluble CD46 that will competitively inhibit opsonized bacteria binding to cell surface CD46. We propose that efficient internalization of uropathogenic E. coli by the human urinary tract depends on cooperation between fimbrial-mediated adhesion and C3 receptor (CD46)-ligand interaction. Complement receptor-ligand interaction could pose a new target for interrupting the cycle of reinfection due to intracellular bacteria.     

Ascorbic acid stimulation of production of a highly branched ,beta-1,3-glucan by Aureobasidium pullulans K-1--oxalic acid, a metabolite of ascorbic acid as the stimulating substance

The production of a highly branched beta-1,3-glucan by Aureobasidium pullulans K-1 in Czapek's medium has been found to be stimulated by ascorbic acid. When the culture supernatant, after removal of polysaccharide from the culture filtrate by ethanol precipitation, was concentrated, then added to a new medium and this strain was cultured in the medium, the polysaccharide production was stimulated the same as when L-ascorbic acid was added to the medium. The stimulating substance was partially purified from the supernatant, and was found to be oxalic acid; 0.03% oxalic acid was the most effective concentration for the stimulation of polysaccharide production. The stimulating substance, oxalic acid, was proved to be derived from ascorbic acid added to a medium in an experiment using L-[1-14C]ascorbic acid. We suggest that oxalic acid generated from the metabolism of ascorbic acid in cells of Aureobasidium pullulans K-1 participated in the stimulation of the polysaccharide production by ascorbic acid.     

Biochemical studies on bilharzial and nonbilharzial hyperoxaluria: effect of pyridoxine and allopurinol treatment

The urinary excretion levels of oxalic acid, calcium, kynurenic, and xanthurenic acids and serum pyridoxal and pyridoxal phosphate concentrations were determined for nonbilharzial and bilharzial hyperoxaluric patients with or without urinary stones. The effects of pyridoxine and allopurinol treatment were also studied. The different groups studied showed elevated levels of urinary oxalic acid, calcium, kynurenic, and xanthurenic acids as well as decreases in serum pyridoxal and pyridoxal phosphate concentrations. These data indicate that nonbilharzial hyperoxaluric patients suffer from dietary B6 deficiency, whereas bilharzial hyperoxaluric patients may suffer from impaired pyridoxine phosphokinase activity. Pyridoxine supplementation is recommended for the treatment of nonbilharzial hyperoxaluric patients. Allopurinol may be the proper drug in the treatment of oxaluria and stone formation or of bilharzial patients.     

Extracorporeal shockwave lithotripsy: urine cytology findings

Objectives:  To describe the urine cytology findings before and after stone therapy with extracorporeal shock wave lithotripsy (ESWL) and discuss its importance.
Methods:  The study consisted of 100 patients with a urinary tract stone (79 renal pelvic stones and 21 upper ureteric stones), 74 were male and 26 were female. The ages ranged 30–55 years. The average duration of symptoms was 3–8 years. The size of the stones varied from case to case ranging from 10.2 to 40 mm. Urine samples were obtained on three consecutive days before and after lithotripsy. The smears were stained by the Papanicolaou method.
Results:  The smears before lithotripsy revealed a few red blood cells, inflammatory cells, epithelial cells and crystals (calcium oxalate, uric acid and triple phosphate). Atypical malignant looking cells and epithelial cell clusters were not noticed. After lithotripsy, the urine samples were examined at different periods, 24 hours, 2 weeks, 1 month, 2 months and 3 months. The smears revealed papillary clusters in all 100 patients within 24 hours and were always associated with inflammation. Atypical malignant looking cells appeared later, within 1–2 months in 21 patients, and were associated with inflammation (19 patients), RBC, crystals and papillary clusters. Most of the papillary clusters and atypical malignant looking cells disappeared before 3 months.
Conclusion:  The epithelial cell clusters and atypical cells were seen in urine smears after ESWL. Without knowing the previous history these findings can be confused with urothelial neoplasms.     

The excretion of lactate dehydrogenase in human urine after ingestion of aspirin

1. Cells present in normal human urine contain 5-10% of the total lactate dehydrogenase excreted. The enzyme released from these cells by ultrasonication contained a distribution of isoenzymes similar to that found in the bulk of the urine and it is suggested that these cells are the main source of urinary lactate dehydrogenase. 2. Cells were thoroughly washed before examination so it is unlikely that the enzyme found in urinary sediment was simply adsorbed. In addition, full recoveries of added lactate dehydrogenase isoenzymes LDH(1) and LDH(5) showed that adsorption did not occur. 3. Most of the cells in normal urine are of the non-squamous epithelial type and their excretion is greatly increased after the ingestion by the subject of 3g. of aspirin. The possible origin of these non-squamous cells from the kidney is discussed. 4. Starch-block electrophoresis and relative activity measurements of lactate dehydrogenase excreted after the subject had taken aspirin show that the enzymes present in urine and cells are very similar, confirming the conclusion reached above (point 1). They have slightly more M subunits than the normal, shown particularly as an increase in isoenzyme LDH(2). The isoenzyme pattern is like that of the kidney medulla and the possible reasons for this are discussed in terms of the concentration of salicylic acid in various parts of the kidney. 5. The results confirm the previous suggestion that the kidney is the main source of urinary lactate dehydrogenase.