Clinical and diagnostic importance of the evaluation of the Ig proteases activity in children with intestinal dysbacteriosis

The specific activity of serine, metal dependent and thiolic Ig proteases in the coprofiltrates of children with manifestations of intestinal dysbacteriosis was determined by the enzyme immunoassay. 56 children with pronounced symptoms of intestinal disorders (37 children aged up to 1 year and 19 children over 1 year) were examined. A group of 25 clinically healthy children was used as control. Simultaneously with protease activity of coprofiltrates, there was detected the level of Ig-degrading activity of the opportunistic bacteria islolates of different taxonomic groups from feces of children with dysbacteriosis of different severity (as determined by the classical bacteriological method). The evaluation of the Ig-proteolytic activity of fecal supernatants, associated with the presence of serine, metal-dependent and thiolic proteases in the intestine, as well as detection of such proteases in microbial isolates, seems to be highly important for the diagnosis of intestinal disorders in children and is recommended for screening of intestinal dysbacteriosis.     

Effects of ceftriaxone‐induced intestinal dysbacteriosis on dendritic cells of small intestine in mice

Intestinal microflora plays a pivotal role in the development of the innate immune system and is essential in shaping adaptive immunity. Dysbacteriosis of intestinal microflora induces altered immune responses and results in disease susceptibility. Dendritic cells (DCs), the professional antigen‐presenting cells, have gained increasing attention because they connect innate and adaptive immunity. They generate both immunity in response to stimulation by pathogenic bacteria and immune tolerance in the presence of commensal bacteria. However, few studies have examined the effects of intestinal dysbacteriosis on DCs. In this study, changes of DCs in the small intestine of mice under the condition of dysbacteriosis induced by ceftriaxone sodium were investigated. It was found that intragastric administration of ceftriaxone sodium caused severe dysteriosis in mice. Compared with controls, numbers of DCs in mice with dysbacteriosis increased significantly (P = 0.0001). However, the maturity and antigen‐presenting ability of DCs were greatly reduced. In addition, there was a significant difference in secretion of IL‐10 and IL‐12 between DCs from mice with dysbacteriosis and controls. To conclude, ceftriaxone‐induced intestinal dysbacteriosis strongly affected the numbers and functions of DCs. The present data suggest that intestinal microflora plays an important role in inducing and maintaining the functions of DCs and thus is essential for the connection between innate and adaptive immune responses.     

Immunoregulation of the population of intestinal gram-negative microflora

The authors present summarized data obtained in their studies on the presence of close feedback relationship between the state of immunity to common antigenic determinants of lipopolysaccharides (LPS), localized on the cell-wall surface of Gram-negative bacteria, and the development of intestinal dysbacteriosis. The problems dealing with the regulation of the amount of intestinal microflora with immunity factors taking part in the mechanism of such regulation are discussed and analyzed. The state of immunity to common antigenic determinants of LPS of Gram-negative bacteria re-flects, seemingly, the total resistance level of the body, i.e. the functional state of the immune system as a whole. The suggestion has been made that the development of intestinal dysbacteriosis may be basically caused by functional disturbances of the immune system, induced by different exogenous and endogenous damaging factors.     

Role of dysbacteriosis in the formation of chronic noninfectious pathology in children

The results of clinical observations and laboratory data make it possible to regard dysbacteriosis as an important factor in the pathogenesis of chronic noninfectious pathology in children. The adequate complex correction of intestinal dysbacteriosis on the basis of probiotic therapy facilitates the prolonged remission of the disease in children with diabetes mellitus of type 1 (DM1) and myopathy, decreases severity of late complications of DM1. A suggestion is made on the role of dysbiotic microflora in the development of chronic non-infectious pathology in children.     

Detection rate of enterotoxigenic Staphylococcus aureus isolated from children with intestinal disbacteriosis

Detection rate of enterotoxigenic Staphylococcus aureus isolated from faeces of 62 children aged from 3 months old to 7 years old with intestinal dysbacteriosis was studied by indirect hemagglutination assay and enzume immunoassay. It was shown that strains of S.aureus producing staphylococcal enterotoxin A (SEA) are prevailed (40.3%) in children with disturbances of intestinal microflora while staphylococcal enterotoxin B (SEB)-producing strains were detected in 20.9% of children. Amount of produced enterotoxin varied for SEA from 125 ng/ml to 2000 ng/ml and for SEB--from 125 ng/ml to 250 ng/ml. Inverse dependence of detection rate of enterotoxin-producing strains in faeces on age of children was established. The most number of enterotoxigenic strains of S.aureus was detected in infants. These data point to expediency of determination of enterotoxin-producing ability of S. aureus strains isolated from children with dysbacteriosis as measure of danger of this microorganism for children's health and indication for adequate actions for its elimination.     

Participation of conditionally pathogenic enterobacteria in the processes of intestinal dysbacteriosis

The presence of a number of conditioned-pathogenic enterobacteria (Klebsiella, Citrobacter, Enterobacter) in patients with intestinal dysbacteriosis, and also their detection in derangement of normal intestinal biocenosis in patients with chronic intestinal disturbances with clinical manifestations of this condition, even in the absence of known bacteriological indications of dysbacteriosis was revealed. Results of investigations led the authors to the conclusion on the participation of a number of conditioned pathogenic enterobacteria in intestinal dysbacteriosis, and permit a suggestion on the necessity of proper assessment of the fact of presence of these bacteria as a possible dysbacteriosis indication.     

Disturbances in the intestinal microflora and immune system in children with vitiligo

A total of 91 children, aged 3-16 years, with vitiligo were examined. These examinations showed that the total number of T lymphocytes decreased irrespective of the degree of intestinal dysbacteriosis. The average number of T suppressors increased as dysbiotic changes in the intestine became more profound. The amount of natural killers, B lymphocytes, as well as the content of IgG and IgA (p < 0.001), increased irrespectively of the degree of intestinal dysbacteriosis. Thus the unbalance of the immunity system and dysbiotic changes in the intestine of children having vitiligo were Inter-related.     

Gut dysbacteriosis and intestinal disease: mechanism and treatment

The gut microbiome functions like an endocrine organ, generating bioactive metabolites, enzymes or small molecules that can impact host physiology. Gut dysbacteriosis is associated with many intestinal diseases including (but not limited to) inflammatory bowel disease, primary sclerosing cholangitis-IBD, irritable bowel syndrome, chronic constipation, osmotic diarrhoea and colorectal cancer. The potential pathogenic mechanism of gut dysbacteriosis associated with intestinal diseases includes the alteration of composition of gut microbiota as well as the gut microbiota–derived signalling molecules. The many correlations between the latter and the susceptibility for intestinal diseases has placed a spotlight on the gut microbiome as a potential novel target for therapeutics. Currently, faecal microbial transplantation, dietary interventions, use of probiotics, prebiotics and drugs are the major therapeutic tools utilized to impact dysbacteriosis and associated intestinal diseases. In this review, we systematically summarized the role of intestinal microbiome in the occurrence and development of intestinal diseases. The potential mechanism of the complex interplay between gut dysbacteriosis and intestinal diseases, and the treatment methods are also highlighted.     

菌群失调小鼠感染鼠伤寒沙门菌后Th1和Th2细胞因子的动态研究

目的研究鼠伤寒沙门菌感染小鼠在菌群失调下Th细胞因子的动态变化,以探讨菌群失调对沙门菌感染的免疫机制。方法分别建立菌群失调、感染和空白对照的小鼠模型。各组动物在感染不同时点处死,观察小肠、肝脏和脾脏病理改变。采用流式细胞仪检测脾脏细胞中IFN-γ和IL-4表达,以此代表Th1和Th2细胞。结果菌群失调组病理损害最重,Th1明显增加,表达水平高,Th2变化不大,Th1/Th2比值升高。结论菌群失调后,能够加重小鼠感染鼠伤寒沙门菌引起的的Th1型反应,产生炎症性损伤。     

菌群失调腹泻造模及七味白术散治疗对小鼠乳糖酶基因13910多态性的影响

目的探讨抗生素及七味白术散对菌群失调腹泻小鼠乳糖酶基因13910位点多态性的影响。方法将36只SPF级小鼠随机分为正常组(12只)、模型组(12只)、七味白术散组(6只)和乳糖酶组(6只),除正常组外的其余小鼠采用混合抗生素造成菌群失调腹泻模型,然后分别灌胃七味白术散和乳糖酶治疗。造模成功和治疗后分别提取小鼠肠道内容物和肠道黏膜宏基因组,对包括小鼠乳糖酶基因13910位点在内的1 036bp长度的DNA片段进行单核苷酸多态性(SNP)测序分析。结果造模和治疗后,小鼠乳糖酶基因13910位点没有发生碱基的变异,均为A/A型,13910位点在内的1 036bp范围内也没有新的SNP位点出现。结论菌群失调腹泻造模与七味白术散治疗对小鼠乳糖酶活性的干预均与小鼠乳糖酶基因13910位点多态性没有相关性,可能存在其他多态性位点或其他方面的调控机制。     

肠道菌群失调与脂肪肝患者血脂和丙氨酸氨基转移酶的变化研究

目的探讨脂肪肝患者体内甘油三酯(TG)、血清总胆固醇(CHOL)、高密度脂蛋白(HDL)、低密度脂蛋白(LDL)、丙氨酸氨基转移酶(ALT)与肠道菌群失调的关系。方法单一他汀类降脂药物治疗高脂血症,测定肠道菌群失调与肠道菌群正常的脂肪肝患者血清TG、CHOL、HDL、LDL、ALT。结果无菌群失调组,ALT升高者占11%,治疗缓解率为87%,而菌群失调组ALT升高占37%,治疗缓解率为67%,两者差异有显著性。结论正常肠道的菌群对血脂代谢以及高脂血症的治疗起着重要作用。     

两种肠内营养方案对重症急性胰腺炎患者 肠道菌群及预后的影响

目的探讨肠内免疫微生态营养和免疫增强型肠内营养方案对重症急性胰腺炎患者肠道菌群及远期预后的影响。方法选择2014年1月至2017年6月在我院就诊的重症急性胰腺炎患者156例。按照随机数字表法将患者分为A组(肠内免疫微生态营养方案组)、B组(免疫增强型肠内营养方案组)和对照组(常规肠内营养方案组),各52例。检测患者治疗前后T淋巴细胞及其亚群NK细胞、B淋巴细胞,血清免疫球蛋白及ALB、TF、PA等营养指标。同时检测患者肠道菌群,判定3组患者肠道菌失调症发生率。治疗后对患者随访6个月,记录并发症及不良预后。结果治疗后A组和B组患者患者CD+4细胞、CD+8细胞、CD+4/CD+8、NK细胞、B淋巴细胞水平显著高于治疗前,对照组患者除CD+8细胞和NK细胞外,其余各细胞水平亦显著高于治疗前(P0.05),且A组和B组患者治疗后各细胞水平高于对照组(P0.05)。治疗后A组和B组患者IgA、IgG、IgM水平显著升高,且A组和B组高于对照组(P0.05),同时3组患者治疗后ALB水平显著高于治疗前,且A、B组高于对照组,但A组和B组治疗后ALB水平比较差异无统计学意义(P0.05)。发病7～10d后,A组患者菌群失调发生率为5.77%,低于B组(19.23%)和对照组(36.54%),两两比较差异均有统计学意义(P0.05)。治疗6个月后,A组患者出现1例胰腺及胰周感染,1例MODS,0例病死;B组出现1例胰腺及胰周感染,2例MODS,3例菌血症,1例腹腔感染,2例病死;对照组出现6例胰周胰腺感染,7例MODS,5例菌血症,3例腹腔感染,3例病死。A组和B组预后显著优于对照组,且A组预后优于B组(P0.05)。结论肠内免疫微生态营养与免疫增强型肠内营养均能显著提高重症急性胰腺炎患者营养状况,提高免疫水平,且肠内免疫微生态营养在改善肠道菌群及预后方面具有更好的效果,值得临床推广。     

The frequency of staphylococcal colonization of the intestines in children with the manifestations of dysbacteriosis

In 2100 children of different age groups the microbiocenosis of the large intestine was studied. The study revealed that the colonization of the mucous membrane of the large intestine with staphylococci developed in 30% of children with intestinal dysbacteriosis. Young children were mainly affected (91%). The prevailing species among isolated staphylococci was S. aureus (86%), capable of persistence in the intestine (30.9%). In children non typing S. aureus strains mainly circulated (70%), and among phage-typing strains isolates of phage group III prevailed (70.2%). The colonization of the intestine with coagulase-negative staphylococci was possible (14%). Microecological intestinal disturbances in children of different age groups were characterized by different degrees of changes in normal microflora with the prevalence of opportunistic microorganisms in the microbial picture.     

Use of antibiotic-resistant Bifidobacterium in treating ulcerative-necrotic enterocolitis in young children

Ulceronecrotic colitis in premature children is accompanied by the development of pronounced intestinal dysbacteriosis characterized by a sharp increase in the number of Escherichia, enterococci, staphylococci and the appearance of opportunistic enterobacteria (Klebsiella, Serratia, Citrobacter, Proteus) in large amounts. Clinical convalescence was observed in 2 weeks in children receiving antibiotic-resistant bifidobacteria with antibiotics and in 3-4 weeks in children receiving commercial bifidobacteria with antibiotics, while children treated only with antibiotics showed no signs of clinical convalescence during the whole course of treatment. After the course of treatment the most effective recovery of the intestinal microflora was observed in the group of patients who had received antibiotics in combination with antibiotic-resistant bifidobacteria. It was manifested by a decrease in the number of Escherichia, Klebsiella, Proteus, Serratia, staphylococci and enterococci simultaneously with an increase in the number of endogenous lactobacilli and bifidobacteria. In those children who had received commercial bifidobacteria in combination with antibiotics or had been treated only with antibiotics the process of the recovery of the intestinal microflora was considerably less pronounced than in the patients of the first group; a decrease in the number of Escherichia, Klebsiella, Proteus and Serratia occurred to a lesser extent, and at the same time an essential increase in the number of enterococci and staphylococci was observed. The level of endogenous lactobacilli and bifidobacteria was considerably reduced. Antibiotic-resistant bifidobacteria actively took in the intestine of the patients. On day 5 after the course of treatment was over their level was (4.3 +/- 0.4) X 10(4) cells/g feces.     

Formation of intestinal microflora in children during the first year of their life

In 525 young children the state of intestinal microbiocenosis was studied every month of the first year their life. The study revealed that the process of the microflora formation lasted throughout the first year of their life and was characterized by dysbiotic disturbances. During this period the aggravation of dysbiotic changes in the intestine of these children on months 3, 6-7 and 11-12 was of particular importance. The formation of stable dysbacteriosis led to a decrease in the immunological status of the child, which was manifested by the increased content of such microorganisms as hemolytic cocci, Proteus and a decrease in the quantitative level of bifidobacteria in the total intestinal microbiocenosis by the end of the first year of child's life.     

Microbiocenosis of the large intestine in acute complicated pneumonia in children

Fifty-six children of early age with pneumonia developed on the background of frequent respiratory infections were placed under observation. In 91.1% of these cases microecological disturbances in the intestine were detected, 46.6% of the patients having third-degree dysbacteriolysis. In such cases it is more correct to regard the "intestinal" syndrome as the clinical manifestation of disturbances in the biocenosis of the intestine, the state of its microflora. Intestinal dysbacteriosis aggravates the course of acute aggravated pneumonia in children and requires the inclusion of special therapy aimed at normalizing intestinal microflora.     

Genetic determinants of Escherichia coli pathogenicity isolated from urine and feces of children with different clinical variants of urinary system infection

In the process of examination of 156 children of different age groups 176 E. coli cultures were isolated; of these, 98 cultures were isolated from acute cystitis and pyelonephritis patients, 28--from urine in cases of aysmptomatic bacteriuria, 30--from feces in cases of asymtomatc bacteriuria and intestinal dysbacteriosis, while 20 cultures--from feces of healthy children. In these bacteria the presence of genes associated with pathogenicity islets (PI) hlyA, hlyB, cnf-1, papC, sfaG and gene irp-2 (iron-regulated protein) was established with PCR. The detection rate of PI determinants in uropathogenic E. coli (UPEC) was shown to depend on the variants of the clinical manifestation of urinary tract infection. The total detection rate of PI gene fragments in UPEC cultures of different origin was indicative of their definitely less frequent occurrence in asymptomatic bacteriuria, observed simultaneously with intestinal dysbacteriosis, in comparison with acute urological infection. Practically the same detection rate of PI determinants in E. coli, isolated in asymptomatic bacteriuria in children, reflected high probability of genetic exchange in the above-mentioned fragments and made it possible to presume the existence of DNA sites, characteristic mainly of pathogenic clones. The established heterogeneity of the detection rate of PI determinants in E. coli clinical isolates requires further study.     

The determination of the antagonistic activity of Solco lactobacteria (Lactobacillus acidophilus Lat 11/83) using gnotobiotic technology

Lactobacillus acidophilus strain Lat 11/83 has been used for the study of its antagonistic activity with respect to pathogenic microorganisms in experiments on conventional germ-free animals. The results of these experiments indicate that the above strain may be recommended as a highly active antagonist for the treatment and prophylaxis of intestinal dysbacteriosis of different etiology.     

The effect of enterococci on normalizing the intestinal microflora in experimental dysbacteriosis

The normal microflora of the intestine produces essential influence on the vital activity of the host. The exposure of the body to the action of different unfavorable factors (roentgen radiation, the administration of antibiotics, Salmonella infection, etc) results in changes in the normal microflora of the gastrointestinal tract. This work was aimed at the study of the influence of Streptococcus faecium YDC-48 on the intestinal microflora of mice in experimental (chemotherapeutic, postirradiation) dysbacteriosis and Salmonella infection. The effect of the oral administration of S. faecium YDC-48 on the correction of the intestinal microflora of mice in cases of dysbacteriosis etiology was studied. The intragastric administration of S. faecium YDC-48 was found to induce an increase in the level of lactobacterin and a decrease in the number of opportunistic microorganisms in chemotherapeutic and postirradiation dysbacteriosis. The oral administration of S. faecium YDC-48 decreased the manifestations of intestinal dysbacteriosis in experimental Salmonella infection. The possibility of developing a preparation on the basis of S. faecium YDC-48, a representative of normal intestinal microflora, is discussed.     

Antibiotic resistance and putative origin of Staphylococcus aureus and Klebsiella strains isolated from the children with intestinal dysbacteriosis

The results of the statistical treatment of data on the analyses of 766 children, the residents of Moscow, for dysbacteriosis are presented; of these children, 34 were aged up to 1 month and 732, from 1 month to 1 year. This study revealed that in the fist year of life in children with dysbacteriosis the dominating bacterial species were S. aureus, bacteria of the genus Klebsiella and fungi of the genus Candida. From the intestine of children aged up to 1 month S. aureus and Klebsiella were isolated more often than from children aged up to 1 year. The results of the study of antibioticograms demonstrated that 21.6% of S. aureus strains and 74.4% of Klebsiella strains were multiresistant to antibiotics. Taking into account the fact that multiresistance to antibiotics was characteristic of hospital strains, the suggestion was made that the isolated strains were of hospital origin and such strains could colonize the intestine of children in maternity hospitals.