Absence Of Bacterial Pathogens Research Articles

Occurrence of Cryptosporidium and other enteropathogens and their association with diarrhea in dairy calves of Buenos Aires province, Argentina

Cryptosporidiosis of neonatal dairy calves causes diarrhea, resulting in important economic losses. In Argentina, prevalence values of Cryptosporidium spp. and other enteropathogens such as group A rotavirus (RVA), bovine coronavirus (BCoV) and enterotoxigenic Escherichia coli (ETEC, endotoxin STa+), have been independently studied in different regions. However, an integrative epidemiological investigation on large-scale farms has not been carried out. In this study, fecal samples (n=908) were randomly collected from diarrheic and healthy calves from 42 dairy farms, and analyzed for the presence of Cryptosporidium spp., RVA, BCoV, ETEC (STa+) and Salmonella spp. In all sampled dairy farms, dams had been vaccinated against rotavirus and gram-negative bacteria to protect calves against neonatal diarrhea. The proportion of calves shedding Cryptosporidium spp., RVA, and BCoV in animals younger than 20days of age were 29.8%, 12.4% and 6.4%, and in calves aged between 21 and 90days, 5.6%, 3.9%, and 1.8%, respectively. ETEC was absent in the younger, and occurred only sporadically in the older group (0.9%), whereas Salmonella spp. was absent in both. The observed sporadic finding or even absence of bacterial pathogens might be explained by the frequent use of parenteral antibiotics in 25.3% and 6.5% of the younger and the older group of calves, respectively, within 2days prior to sampling and/or vaccination of dams against gram-negative bacteria. Diarrhea was observed in 28.8% (95% CI, 24.7-32.8%) of the younger calves and 11.7% (95% CI, 9.1-15.5%) of the older calves. Importantly, Cryptosporidium spp. (odds ratio (OR)=5.7; 95% CI, 3.3-9.9; p<0.0001) and RVA (OR=2.5; 95% CI, 1.2-5.1; p<0.05) were both found to be risk factors for diarrhea in calves younger than 20days old. Based on its high prevalence and OR, our results strongly suggest that Cryptosporidium spp. is the principal causative factor for diarrhea in the group of neonatal calves, whereas RVA seems to play a secondary role in the etiology of diarrhea in the studied farms, with about three-times lower prevalence and a half as high OR. Furthermore, a coinfection rate of Cryptosporidium spp. and RVA of 3.7% was observed in the group of younger calves, which strengthens the assumption that these events are independent. In contrast, due to a low infection rate of enteropathogens in older calves, mixed infection (<< 1%) was virtually absent in this group.

Microbial Colonization Activates an Immune Fight-and-Flight Response via Neuroendocrine Signaling

The ability to distinguish harmful and beneficial microbes is critical for the survival of an organism. Here, we show that bloating of the intestinal lumen of Caenorhabditis elegans caused by microbial colonization elicits a microbial aversion behavior. Bloating of the intestinal lumen also activates a broad innate immune response, even in the absence of bacterial pathogens or live bacteria. Neuroendocrine pathway genes are upregulated by intestinal bloating and are required for microbial aversion behavior. We propose that microbial colonization and bloating of the intestine may be perceived as a danger signal that activates an immune fight-and-flight response. These results reveal how inputs from the intestine can aid in the recognition of a broad range of microbes and modulate host behavior via neuroendocrine signaling.

VIRAL ETIOLOGY OF RECURRENT URINARY TRACT INFECTIONS

Introduction. Recurrent urinary tract infection is an actual problem of modern urology. Objective. Complex investigation of urinary tract infections including viral etiology for chronic recurrent cystitis in women Materials and methods. The study included 31 women with recurrent infection of urinary tract. Inclusion criteria were the presence of lower urinary tract symptoms caused by infection, severe recurrent course, the lack of anatomical and functional disorders of the urinary tract, the absence of bacterial pathogens during the study, taking into account the culture of aerobic and anaerobic culturing techniques. Results. The analysis of the clinical manifestations, the dominant in the study group were pain and urgency to urinate at 100% and 90% of women surveyed, respectively, and less frequent urination were recorded in 16.1% of patients. In general clinical examination of urine in all cases identified leukocyturia and 90% of the hematuria. By using a polymerase chain reaction (PCR) in midstream urine of all examined was verified 10 types of human papilloma virus (HPV) with the predominance of 16 and 18 types . Considering the presence of recurrent infectious and inflammatory processes of the urinary tract, cystoscopy with bladder biopsy was performed for all patients. When histomorphological biopsies of all patients surveyed noted the presence of the specific characteristics of HPV: papillary hyperplasia with squamous koilocytosis, pale cytoplasm and shrunken kernels. When analyzing the results of PCR biopsy data corresponded with the results of PCR in midstream urine in all biopsies was detected HPV. Conclusions. Human papillomavirus infection may be involved in the development of viral cystitis. In the etiological structure of viral cystitis, both highly oncogenic and low oncogenic HPV types can act.

Microbiological quality and aflatoxin B1 content of some spices and additives used in meat

Introduction Being a product of agricultural practice, spices can carry high numbers of microorganisms as well as mycotoxins, especially aflatoxin B1. Thus, effective control of these parameters is a prerequisite for their utilization in the food sector. Objectives The objective of this study was to assess the microbiological quality and the aflatoxin B1 content of 15 additives, 13 spices and 38 spice mixtures used in the meat industry. Methods Three series of samples were taken for analyses. Standard and established methods were used for both microbiological analyses and aflatoxin B1 detection. Results and Conclusion Staphylococcus aureus, enterococci, Bacillus sp., Bacillus cereus, sulphur-reducing clostridia and Escherichia coli were below detection limit in all samples examined. This was also the case regarding the total aerobic mesophilic count, Enterobacteriaceae, coliforms and yeasts/moulds counts of additives. On the other hand, 12 out of 13 spices and 20 out of 38 spice mixtures were found to be contaminated with some of them being of unacceptable microbiological quality according to Recommendation 2004/24/EC. Analyses for aflatoxin B1 content revealed absence or, at least, presence of this contaminant below the detection limit of 1.0 p.p.b. in all samples. The absence of bacterial pathogens and aflatoxin B1 is an important finding regarding the safety of additive, spice and spice mixtures in the meat industry. However, the presence of members of the Enterobacteriaceae family, raise questions regarding the hygienic status of their handling.

Clinical mastitis perceptions of Kansas dairy producers (2003)

Mastitis is considered the most costly disease in the U.S. dairy industry. Treatment of clinical mastitis is the major reason for antibiotic contamination of products on U.S. dairy farms. A survey of 183 dairy producers was conducted to determine their perceptions regarding clinical mastitis treatments and what constituted their treatment regimens. Results indicated that 33% of dairy producers used a coliform vaccine, 10% used a Staphylococcus aureus vaccine, and 38% did no prestripping before milking cows. Obtaining a clinical cure (restoration of normal milk) was considered the most important aspect of mastitis treatment success (110/183; 60%) compared to bacteriological cure (absence of bacterial pathogen), somatic cell count cure (cells count back to near normal concentrations), milk production (back to near pre-mastitis levels), and udder firmness (back to near normal firmness). Average treatment success for mastitis reported by the 183 producers was 70%, with a range of 10 to 100%. Seventy-three (92%) producers listed “off-feed” as a good measure of the severity of clinical mastitis, followed closely by general appearance (91%). Appearance of udder and milk, droopy ears, appearance of the eyes, and low milk production were other popular methods used to determine the severity of clinical mastitis. Dairy producers believed that 5.3 days (range of 1 to 45 days) passed between first recognition of a clinical case until normal milk was restored. Only 34% of producers utilized rectal temperatures as a diagnostic tool for mastitis. Many treatments used were extra-label and some were potentially illegal. However, the results presented demonstrate a wide diversity of products used and a general lack of consensus of what is considered efficacious mastitis treatment. In addition, drug dosages and duration of therapy varied considerably. Greater education on proper dosages, durations, and potential efficacy of treatments should be beneficial. A clear need exists for conducting efficacy studies to help establish necessary and justified treatments for clinical mastitis.

Vaginal pH as a marker for bacterial pathogens and menopausal status

OBJECTIVES: Our purpose was to confirm the elevation of vaginal pH expected in patients with bacterial pathogens in premenopausal women and to examine the relationship of serum follicle-stimulating hormone and estradiol levels to vaginal pH in menopausal patients without and with hormone replacement therapy. STUDY DESIGN: Vaginal pH was determined by phenaphthazine (Nitrazine) pH paper in 253 patients seen in a solo private practice for routine speculum examination. None of the patients were pregnant. Measurements were made of serum levels of follicle-stimulating hormone and estradiol for 172 patients and vaginal cultures were taken from 82 patients. Vaginal pH was correlated with vaginal cultures and serum follicle-stimulating hormone and estradiol levels by use of statistical analysis. RESULTS: Vaginal pH was elevated in all premenopausal patients with documented bacterial pathogens. Serum estradiol levels showed an inverse and serum follicle-stimulating hormone levels a direct statistical correlation with vaginal pH in menopausal patients. CONCLUSIONS: Measurement of vaginal pH is useful, effective, and inexpensive for screening purposes. A vaginal pH of 4.5 is consistent with a premenopausal serum estradiol level and the absence of bacterial pathogens. An elevated vaginal pH in the 5.0 to 6.5 range suggests a diagnosis of either bacterial pathogens or decreased serum estradiol. In patients with an elevated pH, vaginal culture should establish the diagnosis. In the absence of bacterial pathogens, a vaginal pH of 6.0 to 7.5 is strongly suggestive of menopause. Titration of estradiol level by vaginal pH during estrogen replacement therapy may help menopausal women avoid side effects or cessation of therapy. (Am J Obstet Gynecol 1997;176:1270-7.)

Rotaviruses as a cause of nosocomial, infantile diarrhoea in northern Brazil: pilot study.

Faecal samples were obtained from 190 children, aged 0 to 5 years, admitted to a public hospital in Belém, Pará, Brazil. These patients were placed in a pediatric ward with 40 beds distributed in six rooms. Cases were classified into three groups: (a) nosocomial: children who developed gastroenteritis 72 hr or later after admission; (b) community-acquired: patients admitted either with diarrhoea or who had diarrhoea within 72 hr following admission; (c) non-diarrhoeic: those children who had no diarrhoea three days before and three days after collection of formed faecal sample. Specimens were routinely processed for the presence of rotaviruses, bacteria and parasites. Rotaviruses were detected through enzyme-linked immunosorbent assay (ELISA) and subsequently serotyped/electrophoretyped. Rotaviruses were the most prevalent enteropathogens among nosocomial cases, accounting for 39% (9/23) of diarrhoeal episodes; on the other hand, rotaviruses occurred in 8.3% (11/133) and 9% (3/34) of community-acquired and non-diarrhoeic categories, respectively. Mixed infections involving rotavirus and Giardia intestinalis and rotavirus plus G. intestinalis and Entamoeba histolytica were detected in frequencies of 8.6 and 4.3%, respectively, in the nosocomial group. The absence of bacterial pathogens in this category, and the unusual low prevalence of these agents in the other two groups may reflect the early and routine administration of antibiotics following admission to this hospital. Rotavirus serotype 2 prevailed over the other types, accounting for 77.8% of isolates from nosocomial diarrhoeal episodes. In addition, at least five different genomic profiles could be observed, of which one displayed an unusual five-segment first RNA cluster. Dehydration was recorded in all cases of hospital-acquired, rotavirus-associated diarrhoea, whereas in only 57% of nosocomial cases of other aetiology. It was also noted that nosocomial, rotavirus-associated diarrhoeal episodes occur earlier (7 days), following admission, if compared with those hospital-acquired cases of other aetiology (14 days).

Monocyte Fc gamma receptor cross-linking induces IL-8 production.

In response to bacterial cell wall products such as LPS, monocytes produce IL-8, a powerful neutrophil chemotaxin. However, in the absence of bacterial pathogens, immune complex-mediated diseases such as rheumatoid arthritis are associated with high levels of IL-8 in monocyte-rich compartments. Since it is known that IgG-containing immune complexes can recruit neutrophils via an Fc gamma R-dependent process, we hypothesized that cross-linking of monocyte Fc gamma receptors may induce IL-8. To test this hypothesis, peripheral blood mononuclear cells were evaluated for IL-8 induction in response to immobilized LPS-free pooled human IgG. Immobilized IgG, but not soluble IgG, induced IL-8 in a dose-dependent manner (p < 0.05, r = 0.99). This induction corresponded with an up-regulation in IL-8 steady state mRNA levels that peaked at 4 h. The released IL-8 was functional, since supernatants induced concentration-dependent neutrophil migration that was inhibited by a monoclonal anti-IL-8 Ab. Evaluation of purified monocytes for IL-8 production, as well as FACS analysis of IgG-stimulated PBMC preparations, demonstrated that monocytes are the principal IL-8 producer cell. Thus, monocyte Fc gamma R cross-linking induces biologically active IL-8, which may participate in the pathogenesis of immune complex-mediated diseases.

Clinical Aspects of Legionnaires' Disease

Since the initial description of Legionnaires' disease 2 years ago, a clearer picture of its clinical manifestations has emerged as a result of investigations of further epidemics and studies of laboratory-confirmed sporadic cases. Although individual clinical features are not sufficiently distinctive to distinguish Legionnaires' disease from other types of acute pneumonia, a composite can provide a sufficiently characteristic clinical profile to indicate the likelihood of this diagnosis. Such a profile includes high fever (above 39.4 degrees C); recurrent chills; relative bradycardia; early gastrointestinal symptoms (particularly diarrhea); prominent myalgias; microscopic hematuria; liver function abnormalities; toxic encephalopathy; nonproductive cough; absence of bacterial pathogens on Gram stain and culture of transtracheal aspirate; progression from patchy bronchopneumonia to lobar and multilobar consolidation; and frequently prompt and sometimes dramatic response to treatment with erythromycin.

Aseptic meningitis following posterior fossa surgery in children.

✓ The results of suboccipital craniectomy for varying types of posterior fossa pathology in 50 children are reported. Thirty-five (70%) experienced aseptic meningitis postoperatively, with spiking fever and meningismus; cerebrospinal fluid (CSF) studies revealed pleocytosis, high protein values, and depression of glucose. The absence of bacterial pathogens in serial CSF cultures distinguishes this syndrome from septic meningitis. Aseptic meningitis does not respond to antibiotics, but steroids in suitable doses will modify or suppress the clinical and CSF picture. This syndrome may predispose to postoperative hydrocephalus, but steroid therapy may diminish this risk.

A survey of selected bacteriological infections of the Chacma Baboon &lt;i&gt;Papio Ursinus&lt;/i&gt; from the Kruger National Park

An absence of bacterial pathogens and zoonosesemerged as the salient feature in a bacteriological survey ofchacma baboons from the Kruger National Park. Totals varyingfrom 100 to 178 baboons were assayed for salmonellosis, shigel-losis, tuberculosis, brucellosis and leptospirosis. It is conjecturedthat with Kruger National Park baboons, the abovementionedpathogens are not expected to complicate handling proceduresor experimentation, provided a clean or pathogen-free environment is maintained from the day of capture onwards.