Distribution of lactobacilli in the porcine gastrointestinal tract

Abstract Characteristics of the lactobacilli colonizing the various regions of the porcine gastrointestinal tract were investigated. The lumenal contents from the gastric, jejunal, cecal and colonic regions, and biopsies from the gastric non-secreting and secreting regions were homogenized and serial dilutions were spread on Rogosa agar and colonies (50 per region and animal) were randomly sampled. The lactobacillus isolates were grouped according to their protein profiles of lysozyme-treated whole cells. Several different groups of lactobacillus could be detected. Specific groups were associated and often unique for the stomach, jejunal, cecal and colonic regions of the gastrointestinal tract. A few groups were uniformly distributed through the tract. Although published studies of lactobacilli colonizing stomach mucosa have been restricted mainly to the non-secreting region, significant levels were also detected on the secreting stomach tissue. Population densities ranged from 2 × 10⁴ to 2 × 10⁶ CFU per cm² on both the secretory and non-secretory regions. Of the isolates which colonized the gastric secreting epithelium, 26% formed smooth colonies and 74% formed rough colonies. In contrast, the non-secreting epithelium was mainly colonized by lactobacilli forming smooth colonies (67%). From this study, one can suggest that different lactobacilli are associated with specific regions of the gastrointestinal tract, and that some specific groups appear to be restricted to defined regions.     

Nesfatin-1 – More than a food intake regulatory peptide

Nesfatin-1 was discovered a decade ago and despite the fact that it represents just one of a multitude of food intake-inhibiting factors it received increasing attention. This led to a detailed characterization of NUCB2/nesfatin-1's physiological property to reduce food intake and also gave rise to an involvement in the long term regulation of body weight, especially under conditions of obesity. In addition, studies indicated the involvement of NUCB2/nesfatin-1 in other homeostatic functions as well: glucose homeostasis, water intake, gastrointestinal functions, temperature regulation, cardiovascular functions, puberty onset and sleep. These pleiotropic actions underline the physiological relevance of this peptide. Recently, the involvement of NUCB2/nesfatin-1 in psychiatric disorders such as anxiety has been investigated giving rise to the speculation that NUCB2/nesfatin-1 represents a peptidergic link between eating and anxiety/depression disorders.     

Some effects of shark nets in the Natal nearshore environment

Synopsis Protective gillnets (shark nets) have been successful in reducing the frequency of shark attacks on the coast of Natal, South Africa. This is achieved primarily through a reduction in numbers of large sharks. The nets also take a by catch of dolphins, sea turtles, batoids and teleosts. Concern has been expressed over the direct effect of mortalities on the various stocks and also the broader, indirect effects on the inshore system. Catch rates of most shark species declined initially but have shown no trend since the mid-1970s. A first estimate of the reduction in total shark numbers is provided, and factors such as stock identity and net avoidance are discussed. Turtle and teleost stocks do not appear to be threatened by net mortalities but marine mammalogists are investigating the sustainability of catches of two dolphin species. Certain batoids may have declined despite a high release rate, but more data are needed. A published contention that shark netting has resulted in a proliferation of small sharks through reduced predation is re-examined and considered to be exaggerated. Reduced predation on dolphins, as a result of shark netting, is estimated.     

建立胃癌实验动物模型方法的研究

目的通过对人低分化胃癌细胞系SGC-7901状态和接种细胞数目的研究,建立良好的皮下接种胃癌的动物模型。方法采用腹腔注射SGC-7901细胞,使裸鼠形成腹水;光镜及电镜观察细胞状态;将购买的SGC-7901细胞以及形成腹水后的肿瘤细胞分别以1×108、1×107和1×106个进行裸鼠皮下接种,每组接种5只。观察其肿瘤形成时间、大小、状态及病理学变化。结果SGC-7901细胞接种裸鼠形成腹水后进行培养的肿瘤细胞增殖状态发生改变;购买的SGC-7901细胞以1×108及1×107接种裸鼠,在第21天肿瘤组织中央均出现出血和坏死;1×106的裸鼠第21天未见肉眼可见的肿瘤形成。腹水培养的肿瘤细胞,接种1×108的裸鼠在第21天肿瘤组织中央可见大面积的出血和坏死;接种1×107及1×106的裸鼠在第21天均未见出血和坏死,接种1×107的肿瘤组织体积较大。结论SGC-7901细胞接种裸鼠形成腹水后的细胞,更容易建立SGC-7901细胞皮下接种的胃癌动物模型,其中以接种细胞数为1×107的肿瘤生长较好,更适用于胃癌的实验研究。     

胃肝样腺癌的临床病理特征

目的探讨胃肝样腺癌（hepatoid adenocarcinoma of the stomach,HAS）的临床病理学特点、发生机制和免疫组化特征,以提高诊断水平。方法收集并分析5例胃肝样腺癌的临床特征和病理资料,采用HE染色、免疫组化方法,并复习文献。结果组织学胃肝样腺癌具有管状腺癌、粘液性癌和肝样分化腺癌的移行过渡,肿瘤细胞呈小梁状、巢团状,间质为丰富的血窦。免疫表型胃肝样腺癌AAT（5／5）、ACT（5／5）、CEA（5／5）、AFP（4／5）均为阳性,Heppar1灶性阳性（2／5）。结论胃肝样腺癌是一种少见的高度恶性、侵袭性强的特殊类型胃癌,组织学呈肝细胞样腺癌,免疫表型AFP、AAT和ACT阳性有助诊断。     

正常大鼠胃黏膜中肌球蛋白轻链激酶定性和定位观察

目的观察正常大鼠胃组织中肌球蛋白轻链激酶的表达及分布特点。方法取11只SD正常雄性大鼠,在饥饿状态下,处死后取胃组织。通过免疫组化染色,观察正常大鼠胃组织中MLCK的表达及分布。结果MLCK在黏膜肌层、肌层和黏膜下层血管壁平滑肌均有大量表达;在胃底腺中,MLCK主要表达于壁细胞和主细胞胞浆内。结论MLCK不仅存在于平滑肌细胞内,还分布于胃底腺壁细胞和主细胞内,可能参与胃底腺腺细胞的分泌活动。     

Chronic metformin intake and gastric cancer: A pooled analysis within the Stomach cancer Pooling (StoP) Project

IntroductionThe association between chronic use of metformin and risk of gastric cancer (GC) has been investigated with contradicting results. We aimed to study the association between chronic use of metformin and GC by using data from the Stomach cancer Pooling (StoP) Project, an epidemiological consortium of case-control studies on GC.MethodsData from three studies of the StoP Project with available information on metformin intake were analyzed.Multivariable logistic regression models were used to estimate study-specific odds ratios (ORs) and 95% confidence intervals (CIs) for the association between chronic use of metformin and GC risk. Analyses were adjusted for sex, age, socioeconomic status, body mass index, smoking status, alcohol drinking status, and history of diabetes. Study-specific ORs and 95% CIs were then pooled with a random-effects model.The dose-response relationship between the duration of metformin intake and GC was assessed with a one-stage logistic model, and the duration of intake was modelled using second-order fractional polynomials.ResultsThe OR of GC in metformin users versus non-users was 1.01 (95% CI=0.61, 1.67). The association between metformin and GC did not change among different strata of study participants’ characteristics or when restricting the analyses to those with a history of diabetes.The dose-response analysis showed a slightly reducing trend in the OR of GC and a borderline significant association with increasing duration of metformin intake.ConclusionsThe results of our study do not clearly support an association between chronic use of metformin and GC, warranting further research.     

Variations in enzyme activity in stomach and pancreatic tissue and digesta in piglets around weaning

A study was performed to investigate the effect of weaning at 4 weeks of age on the activity of digestive enzymes in the stomach and pancreatic tissue and in digesta from 3 days prior to weaning to 9 days postweaning in 64 piglets. In stomach tissue the activity of pepsin and gastric lipase was determined. Pepsin activity declined abruptly after weaning but 5 days postweaning the weaning level was regained and in the gastric contents no change in pepsin activity was observed. Weaning did not influence the activity of gastric lipase. The activity of eight enzymes and a cofactor was measured in pancreatic tissue. The effect of weaning on the enzyme activity was highly significant for all enzymes except elastase. The activity of all enzymes remained at the weaning level during day 1–2 postweaning followed by a reduction of the activity. The activity of trypsin, carboxypeptidase A, amylase and lipase exhibited minimum activity 5 days postweaning. Trypsin activity increased to the preweaning level on day 7–9 whereas the activity of the others increased but did not reach the preweaning level. The activity of chymotrypsin, carboxypeptidase B and carboxyl ester hydrolase decreased during the entire experimental period. In digesta no effect of weaning was observed on the activity of amylase and trypsin. The activity of chymotrypsin was reduced after weaning in the proximal third of the small intestine and lipase and carboxyl ester hydrolase activity was reduced in the middle and distal parts of the small intestine after weaning. The present study shows that the activities of the digestive enzymes in the pancreatic tissue are affected by weaning. Even though the pancreatic secretion cannot be judged from these results they show that the enzymes respond differently to weaning. In general the activity of the digestive enzymes in pancreatic tissue is low on day 5 postweaning which in interaction with other factors may increase the risk of developing postweaning diarrhoea.     

局部进展期胃癌术前动静脉结合化疗的疗效观察

目的:局部进展期胃癌,即使没有出现远处转移或腹膜种植,预后也极不理想.我们对局部进展期胃癌患者进行术前mECF方案的动静脉结合化疗,以评价其治疗疗效.方法:选取自2009年1月至2011年6月间我院局部进展期胃癌Ⅱ-ⅢC期患者38例,均由影像学确定淋巴结高度可疑转移或浸润、包绕主要血管结构,且没有发现远处转移或腹膜种植,进行2个周期的术前动静脉结合化疗后,行手术治疗.记录化疗毒性反应、临床、病理缓解率、手术并发症发生率和病死率以及1年无病生存率.结果:化疗毒性反应低,3级反应不超过10％,仅有1例出现4级反应,表现为腹泻、恶心和呕吐.38例患者中临床CR有6例,占15.8％,PR17例,占44.7％,NC13例(34.2％),PD2例(5.3％),RR为60.5％(23/38).全部患者均施行了手术,37例患者进行了根治性手术,R0切除率为97％.病理缓解率为5例完全缓解(13.2％),21例部分缓解(55.3％),8例轻微缓解(21.1％),4例未缓解(10.5％).手术并发症发生率为7.9％,无治疗相关死亡发生.1年无病生存率为81.6％.结论:局部进展期胃癌患者术前进行mECF方案的动静脉化疗毒性反应低,疗效理想,之后行手术完整切除后临床效果突出,是理想的治疗方法.