The extent of immune response impairment vs. the prevalence and clinical form of oral candidiasis in HIV patients

The objective of the study was a mycological and clinical evaluation of the course of oral cavity fungal infection in HIV patients in relation to the immune response impairment. The patients were examined physically (symptoms and signs) and mycologically (isolation and identification of fungi, semiquantitative evaluation their growth abundance in the cultures); the immunity status was expressed in terms of the number of CD4 lymphocytes. The most frequently isolated fungal species was Candida albicans. The decreasing immunity was conductive to more abundant fungal growth in the oral cavity as well as to more frequent occurrence of clinical manifestations of candidiasis.     

Bacterial-fungal associations in the intestine under the conditions of colonization by yeast-like fungi of the genus Candida

The composition of the fecal microflora in somatic patients and patients with enteric infections under the conditions of surpluscolonization by yeast-like fungi of the genus Candida was analyzed. The study revealed that the high level of fungal contamination was linked with decreased colonization resistance of the intestine (deficiency in bifidoflora) and with the presence of opportunistic microorganisms: Staphylococcus aureus, hemolytic and lactose-negative Escherichia coli, as well as nonfermenting Gram negative bacteria. The antilysozyme activity of enterobacteria was found to increase in the course of their joint cultivation with fungi of the genus Candida, that may be regarded as one of the mechanisms of the formation and maintenance of pathobiocenosis.     

HLA-DR expression on CD8 lymphocytes from gastric mucosa in urease-positive and urease-negative gastritis

Abstract We isolated lymphocytes from chronically inflamed gastric mucosa. We analysed the expression of IL-2 receptors (CD25), transferin receptors (CD71) and HLA-DR molecules on T lymphocytes by flow cytometric analysis in 16 patients with urease-positive and in 7 patients with urease-negative chronic gastritis. In G0, G1 and G2 histological type (Sydney classification) of gastritis the number of lymphocytes obtained from the gastric mucosa biopsies was too low for the flow cytometric analysis. However, in G3 histological type of chronic gastritis we obtained enough cells for the flow cytometric analysis in 75 %. We demonstrated a significant increase in HLA-DR expression on CD8 cells from patients with urease-positive gastritis compared to urease-negative gastritis. We also observed a statistically non-significant increase in HLA-DR expression on CD3 cells, and in CD71 expression on both CD3 and CD8 cells in urease-positive gastritis. However, no difference in CD25 expression was found between the two types of gastritis.     

The antilysozyme activity of yeasts in the genus Candida

The fungi of the genus Candida isolated from patients with oral mucosa candidiasis and from candidiasis carriers have been studied for their antilysozyme activity. These fungi (Candida albicans, C. tropicalis, C. krusei, C. quilliermondii) are antilysozyme-active. A high antilysozyme activity of the fungi isolated from patients with oral mucosa candidiasis permits supposing that the presence of this trait may be one of the factors of microorganism pathogenicity. The effective antimycotic therapy (clotrimasole, sanguirhitrin) decreases the antilysozyme activity of fungi of the genus Candida.     

Antibacterial protection and the microbiological status of the oral cavity in Sj?gren's disease

The microflora of the oral cavity was studied with a view to the evaluation of the microbiological status and the content of lysozyme in mixed saliva samples from 14 patients with Sj?gren's syndrome and the control group of 19 persons. Disturbances in the biocenosis of the oral cavity of the patients, characterized by the increased occurrence of rod-shaped forms of lactobacilli, yeast-like fungi of the genus Candida and cariogenic streptococci (S. mutans) in the cultures obtained by the inoculation of oral smears, was detected. This "cariogenic situation" was confirmed by clinical data on the stomatological status. In patients with Sj?gren's syndrome the intensity of caries, determined by the ratio of carious, filled and extracted teeth, was high and reached 27.4 +/- 1.0 in comparison with 15.3 +/- 0.7 in the control group (P less than 0.05). A decrease in the level of mixed saliva secretion and in the content of lysozyme in secreted saliva was noted in the patients in comparison with the control group (P less than 0.05). The results thus obtained indicate that in Sj?gren's syndrome the use of the preparations of eubiotic microorganisms with a view to the correction of the microflora of the oral cavity, as well as the application of 0.1% lysozyme solution to the mucous membrane of the oral cavity, may be recommended among other therapeutic measures.     

Species Distribution and Virulence Factors of Candida spp. Isolated from the Oral Cavity of Kidney Transplant Recipients in Brazil

Although yeasts belonging to the genus Candida are frequently seen as commensals in the oral cavity, they possess virulence attributes that contribute for pathogenicity. The aims of the present study were to study the prevalence of Candida spp. isolated from the oral cavity of renal transplant recipients and to analyze strains virulence factors. We isolated a total of 70 Candida strains from 111 transplant recipients, and Candida albicans was the most prevalent species (82.86 %). Oral candidiasis was diagnosed in 14.4 % kidney transplant patients, while 11 isolates (15.7 %) corresponded to non-Candida albicans Candida (NCAC) species. C. albicans adhered to a higher extension than NCAC strains. Some isolates of Candida tropicalis were markedly adherent to human buccal epithelial cells and highly biofilm-forming strains. Regarding proteinase activity, Candida orthopsilosis was more proteolytic than Candida metapsilosis. Candida glabrata and Candida dubliniensis showed very low ability to form biofilm on polystyrene microtiter plates. We have demonstrated here diverse peculiarities of different Candida species regarding the ability to express virulence factors. This study will contribute for the understanding of the natural history and pathogenesis of yeasts belonging to the genus Candida in the oral cavity of patients who were submitted to kidney transplant and are under immunosuppressive therapies.     

The microflora of ulzerous zone mucosa in patients with duodenal ulcer

Bacteriological study of the biopsies taken from gastric and duodenal mucosa of 10 healthy volunteers and 74 patients with duodenal ulcer, was carried out. In the gastroduodenal zone of healthy subjects microorganisms of 6 genera (Streptococcus, Candida, Staphylococcus, Bacillus, Helicobacter and Lactobacillus) were detected. H. pylori was isolated in 20% of cases only in biopsy specimens taken from the antral section of the stomach of healthy as monoculture or in combination with C. albicans. In patients with duodenal ulcer activation of opportunistic microflora was observed in the periulcerous zone. More often H. pylori occurred in associations with fungi of the genus Candida, streptococci, staphylococci, enterobacteria, Pseudomonas and other microorganisms (of more than 30 genera). Quantitatively the dominating microorganisms (3.8-5.7 lg CFU/g) were H. pylori, fungi of the genus Candida, bacteria of the genera Streptococcus, Peptostreptococcus, Bacteroides, Gemella, Prevotella, Veillonella, Peptococcus, Bacillus, different species of opportunistic enterobacteria, as well as bacteria of the genera Staphylococcus, Micrococcus, Corynebacterium, Neisseria, Pseudomonas, etc. Opportunistic bacteria detected in the ulcerous zone, as a rule, expressed hemolytic, lecithinase, RNAase, caseinolytic, catalase and urease activity. Sonicated filtrates of such cultures produced a cytotoxic effect on cells HEp-2. Ulcer is an infected wound that needs sanitation.     

Vaginal microflora in girls of prepuberal age

The bacteriological study of vaginal microflora in 24 clinically healthy girls aged 7-8 years was carried out. Two criteria of normal vaginal biocenosis in girls of prepuberal age were proposed. The proportion of hemolytic bacteria in the vagina of a girl of prepuberal age could reach 100% of all microflora, provided the total bacterial count (TBC) exceed average values. A high proportion of hemolytic bacteria in the vaginal microflora of girls of prepuberal age in combination with a high level of TBC (even with TBC not exceeding the upper limit of its normal value) could probably by regarded as a border state. No fungi of the genus Candida should be isolated from vagina in girls of prepuberal age. Facultative anaerobic microflora was represented mainly by Staphylococcus epidermidis and S. saprophyticus. In 64.3 +/- 12.8% of cases bifidobacteria were detected in the girls vagina.     

In Vitro Evaluation of Putative Virulence Attributes of Oral Isolates of <Emphasis Type="Italic">Candida</Emphasis> spp. Obtained from Elderly Healthy Individuals

Identification of Candida isolates obtained from oral cavity of elderly healthy individuals revealed the predominance of non-albicans Candida species (88.9%) compared to Candida albicans (11%). CHROMagar Candida differential medium and PCR revealed the presence of Candida tropicalis (33.3%), Candida glabrata (27.8%), and Candida krusei (16.7%). We investigated the presence of virulence attributes in a total of 18 isolates, including acid protease and phospholipase production, hemolytic activity, and biofilm production. Extracellular protease was found in five isolates (27.8%) whereas extracellular phospholipase was found in three isolates (17%). All isolates showed hemolytic activity. About 56% of the isolates were weakly positive for biofilm formation (score +) whereas a minority (5.6%) of them showed strong biofilm formation (score 4+). Susceptibility in vitro of the isolates to fluconazole was carried out by microdilution method. Fluconazole showed a strong inhibition against most buccal isolates. The resistant isolates were 2 C. tropicalis, 2 C. glabrata, and 1 C. krusei.     

Antistaphylococcal activity of the complex of natural cytokines

The in vitro study of the action of the complex of natural cytokines (CNC), or preparation Superlymph, on different microbial test strains (Staphylococcus aureus, Escherichia coli, yeast-like fungi of the genus Candida) was carried out. CNC suppressed the growth of S. aureus test culture, depending on the concentration of the preparation. The inhibiting effect was observed in the presence of Ca and Mg bivalent cations in the medium. Under the chosen conditions of the experiment CNC did not inhibit the growth of E. coli test cultures, as well as test cultures of yeast-like fungi of the genus Candida. In addition to its antibacterial effect, Superlymph also produced some effect on the release of cathepsin G, the lysosomal enzyme of human leukocyte granules.     

Activity of hydrolytic enzymes of Candida albicans strains isolated from patients with periodontal and membrane mucosae of oral cavity diseases

Fungi are elements of the ontocenosis of the oral cavity and causal factors of inflammatory lesions in its mucous membrane. The objective of the study was to find differences in the activity of hydrolytic enzymes of Candida albicans isolated from patients with diseases of the periodontium and mucous membrane of the oral cavity. Of 235 patients examined, 31 were diagnosed with gingivitis, 38 with glossitis, 28 with leucoplakia, 37 with adult periodontitis, 25 with juvenile periodontitis, 36 with stomatitis prothetica and 40 with stomatitis atrophica. In 196 patients (83.4 ± 2.4%), fungi belonging to Candida species were detected. In the evaluation of Candida albicans strains (146) properties, bioMerieux API ZYM tests containing substrates for the detection of 19 hydrolases were used. All the investigated strains were characterized by the activity of 14 enzymes, i.e. phosphatase alcaline, esterase (C4), esterase lipase (C8), leucine and valine arylamidase, phosphatase acid, naphthol-AS-BI-phosphohydrolase, α galactosidase, β galactosidase, α glucosidase, β glucosidase, N-acetyl-β-glucosaminidase, α mannosidase and α fucosidase. Strains isolated from the oral cavity of patients with diseases of periodontium and mucous membrane are characterised by the highest phosphatase acid activity. The greatest enzymatic activity is characteristic of Candida albicans isolated from patients with stomatitis atrophica or stomatitis prothetica, and the lowest in strains from gingivitis or juvenile periodontitis cases. Differences in the activity of hydrolases are statistically significant (p<0.01) for: esterase (C4), leucine and valine arylamidase, phosphatase acid, naphthol-AS-BI-phosphohydrolase, β glucosidase, N-acetyl-β-glucosaminidase, of fungi isolated from patients with particular clinical diagnoses. This revised version was published online in June 2006 with corrections to the Cover Date.     

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.     

Dysbacteriosis in patients with colon polyposis

The study revealed the most profound changes in the composition of intestinal microflora in patients with polyposis of the large intestine. In these patients anaerobic microflora (bifidobacteria, lactic acid bacteria) was more often suppressed than in other examined groups, in particular, patients with cholelithic disease. The associations of hemolytic Escherichia with Klebsiella pneumoniae, Pseudomonas aeruginosa, Citrobacter freundii were often observed as well as the increased content of enterococci and fungi of the genus Candida. The determination of frequency and degree of manifestations showed that dysbacteriosis was registered in the absolute majority of patients (97.4%) with polyposis of the large intestine. Among patients with cholelithic disease disturbances in microbiocenosis were detected in 60.0% of cases, the profundity and character of the microflora composition changes being less pronounced.     

Role of persisting opportunistic bacteria in the pathogenesis of the gastric and duodenum ulcer

Dynamic study of the bacterial microflora of 122 patients with gastric and duodenal ulcer was carried out. Microflora examination of the bioptic samples of mucosa, obtained from the ulcerous zone of the patients, revealed that an open ulcer is like an infected wound needing sanitation. In the focus of lesion microorganisms of 32 genera and species, including Helicobacter pylori, fungi of the genus Candida, representatives of the genera Streptococcus, Staphylococcus, Corynebacterium, Bacteroides, etc., were detected. Opportunistic microorganisms were isolated in associations (up to 8 different cultures), possessing cytotoxic, hemolytic, antilysozyme, lecithinase, caseinolytic and RNAase activities. To inhibit the microflora, chitosan was used; 82-85% of the cultures of different bacteria under study proved to be sensitive to it. The inclusion of chitosan into the complex therapy suppressed the persistence of H. pylori, ensured the sanitation of mucosa affected by opportunistic bacteria and accelerated ulcers cicatrization.     

Malignant pleural effusions due to small cell carcinoma of the lung. An immunocytochemical cell-surface analysis of lymphocytes and tumor cells

Thirteen malignant pleural effusions due to small cell carcinoma (SCC) of the lung were immunocytochemically studied using the peroxidase-antiperoxidase adhesive slide assay for the determination of cell surface antigens. A panel of monoclonal antibodies (MAbs) was used to determine the lymphocyte subpopulations and the reactivity of the tumor cells. Of the lymphocytes, 87 +/- 1% were CD3+ T cells, with 72 +/- 10% CD4+ helper/inducer T cells and 20 +/- 5% CD8+ suppressor/cytotoxic T cells. Only a minority of T lymphocytes were activated in terms of expressing the surface markers CD38 and HLA-DR. The distribution of the lymphocyte subpopulations was not significantly different from the distribution in other malignant and nonmalignant pleural diseases previously studied, indicating that the reaction pattern of the lymphocytes in the pleural cavity is similar in different diseases. The tumor cells from all cases were positive for LeuM1, CD16 and HLA-DR; 10 of 11 cases were positive for HEA-125, Sam 2 and Sam 10. Positivity for epithelial membrane antigen was observed in 11 cases, for OKT9 in 8 cases and for carcinoembryonic antigen in 6 cases. A total or partial loss of the reactivity with HLA-1 was found in nine cases. The reactivity pattern of the tumor cells with the MAbs used in this study is not specific for SCC of the lung because other carcinoma cells also reacted with these markers. Additional morphologic criteria, such as cell size and cell configuration, are needed to recognize the immunocytochemically positive-reacting cells as tumor cells from SCC of the lung. However, the immunostaining allows a better identification of the tumor cells, especially in cases with a small quantity of tumor cells.     

Beta-glucan,extracted from oat,enhances disease resistance against bacterial and parasitic infections

The effect of beta-glucan, extracted from oats, on the enhancement of resistance to infections caused by Staphylococcus aureus and Eimeria vermiformis was studied in mice. In vitro study using macrophages isolated from the peritoneal cavity showed that beta-glucan treatment significantly enhanced phagocytic activity. In vivo study further demonstrated that beta-glucan treatment induced a significant (P<0.05) protection against the challenge with 5 x 10(8) of S. aureus in mice. Fecal oocyst shedding in the C57BL/6 mice infected with E. vermiformis was diminished by beta-glucan treatment by 39.6% in intraperitoneal and 28.5% in intragastric group compared to non-treated control. Patency period was shorter and antigen (sporozoites and merozoites) specific antibodies were significantly (P<0.05-0.01) higher in beta-glucan-treated group compared to non-treated control group. There were an increasing number of splenic IFN-gamma-secreting cells in glucan-treated group via intraperitoneal route, which might be responsible for the enhancement of the disease resistance. Glucan treatment was able to effectively change the lymphocytes population (Thy 1.2(+), CD4(+) and CD8(+) cells) in the mesenteric lymph nodes and Peyer's patches in mice infected with E. vermiformis. In conclusion, the oral or parenteral oat beta-glucan treatment enhanced the resistance to S. aureus or E. vermiformis infection in the mice.     

Microbiological aspects of enteric dysbacteriosis in patients of different age groups, visiting outpatient clinics of Moscow

The analysis of the intestinal microflora in 2,378 patients of different age revealed changes in the state of enteric microflora in all examined patients. In the maximum percent of cases a decrease in the amount of bifidobacteria was observed in children of up to 1 month old and in the amount of lactobacilli, in children aged 6 - 14 years. In patients of all age groups the representatives of such facultative microflora as Staphylococcus aureus or fungi of the genus Candida dominated. The highest proportion of isolated staphylococci was characteristic of children in the first year of life. In the highest percent of cases a decrease in the amount of Escherichia coli with typical properties was observed in persons over 65 years old. Other enterobacteria were most often isolated from adults aged 56 - 65, but the percentage of their isolation was 1.5 times lower than that of Candida. The conclusion was made that the treatment of patients with quantitative and qualitative disturbances of normal enteric microflora needed individual approach in each concrete case with due regard to the patient's age.     

Antigen-driven expansion and contraction of CD8+-activated T cells in primary EBV infection.

The origin of the increased numbers of CD8+ atypical lymphocytes, expressing activated markers such as HLA-DR or CD45RO, in the peripheral blood of patients with infectious mononucleosis (IM) has been debated. Using a recently developed assay to detect intracellular accumulation of IFN-gamma in EBV-reactive T cells by FACS, we have demonstrated that 34-54% of HLA-DR+/CD8+ and 34-60% of CD45RO+/CD8+ T cells in the PBMCs of febrile patients suffering from IM are EBV-specific. The EBV-specific CD8+ T cell counts in the PBMCs of four febrile patients suffering from IM ranged between 2,260 and 8,200/microl, decreasing to 5.1% and 7.9% of the counts in the first samples over 10 days in two donors. The decline of CD8+ T cell subpopulations, namely HLA-DR+, CD45RO+, and EBV-specific T cells, was in parallel with the drop in the EBV genome load. These data indicate that the Ag-driven expansion of CD8+ T cells and subsequent contraction with the Ag decline in vivo in humans is effective for clearing virus-infected cells with minimal disturbance of the homeostasis of the immune system.     

Frequency analysis of IgE-secreting B lymphocytes in persons with normal or elevated serum IgE levels

The immunoregulatory mechanisms that determine the high serum IgE antibody levels in disorders such as helminth parasite infections and the hyper-IgE recurrent infection syndrome (HIE) remain poorly understood. To assess whether elevated serum IgE levels result from an increased number of B lymphocytes committed to IgE production, the proportion of IgE-producing B lymphocytes was determined by a filter immunoplaque assay using PBMC from persons with a broad range of serum IgE levels that included normal persons (n = 9) and patients with loiasis (n = 12), tropical pulmonary eosinophilia (TPE) (n = 6), lymphatic filariasis (n = 28), and HIE (n = 8). PBMC from these persons were assessed for production of in vitro IgE. The geometric mean number of IgE-secreting cells in 10(5) B lymphocytes in PBMC was 0.42 (range 0-2.2) in normal persons, 5.6 (range 0.1-35.5) among patients with loiasis, 9.4 (range 0-53.2) among patients with lymphatic filariasis, 52 (range 31.5-115) among patients with TPE, and 218 (range 56-1404) among patients with HIE. When all study subjects were grouped, there were significant correlations with serum IgE levels (r2 = 0.78; p less than 0.0001) and net spontaneous in vitro IgE production (r2 = 0.8; p less than 0.0001). Estimates of the amount of IgE production per B lymphocyte were similar among normal persons, patients with filarial infections, and patients with TPE (geometric means of 134, 96, and 141 pg/ml/cell, respectively); in contrast, for HIE patients, IgE production by individual B cells was significantly lower (geometric mean 28 pg/ml/cell; p less than 0.001). These observations demonstrate that clonal expansion of IgE-producing B lymphocytes is a major mechanism underlying the elevated serum IgE levels seen in persons with hyper-IgE states.     

The dynamic immunological indices in in vivo stimulation with a Candida antigen

The results of the study of some immunity characteristics in patients with broncho-pulmonary diseases of allergic etiology, appearing under the influence of yeast-like fungi of the genus Candida, before the intradermal injection of Candida antigen and 24 and 48 hours after such injection are presented. A decrease in the content of peripheral blood lymphocytes, in the levels of T- and B-cells, changes in the frequency and intensity of immediate and delayed hypersensitivity reactions under the influence of antigenic stimulation have been established.