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At least 1,045 records · Page 58Linked to original sources
PubMed1982

Piperacillin v Carbenicillin in the therapy for serious infections.

One hundred seven patients were treated with either piperacillin (56) or carbenicillin (51) in an open randomized trial of hospitalized patients with pleuropulmonary (40), urinary tract (26), gynecologic (21), skin and soft-tissue (eight), joint (five), bone (three), and miscellaneous other infections (four). Patients with urinary tract infections were given 150 mg/kg/day of piperacillin sodium or 200 mg/kg/day or carbenicillin sodium in divided doses every six hours intravenously. Patients with other infections were given 250 mg/kg/day of piperacillin sodium and 450 mg/kg/day of carbenicillin sodium; 53/56 (95%) patients treated with piperacillin and 45/51 (88%) patients treated with carbenicillin were cured clinically. In general, the drugs were well tolerated. There were, however, more adverse experiences in the groups taking carbenicillin. Of special interest was the finding of liver function test abnormalities in 17/78 (21%) carbenicillin recipients (evaluative and nonevaluative cases). We concluded that piperacillin was effective and safe. It has potential for use in a great variety of infections.

Adult↗
PubMedDate not supplied

Open clinical trial of roxithromycin amongst patients of Jos University Teaching Hospital with lower and upper respiratory tract infections.

An open non-comparative clinical study to determine the efficacy and tolerance of Roxithromycin 150 mg twice daily was carried out amongst Nigerian patients with acute upper and lower respiratory tract infections. Twenty-four (24) patients (mean age 21.6 years, male 13; females 11 who completed the study presented with acute tonsillitis (33.3%, acute bronchitis (12.5%), lober pneumonia (12.5%), Otitis media (8%), acute pharyngitis (4%) and acute sinusitis (4%). Most of the patients had normal bacterial flora isolated (50.3%). Pathogens isolated included streptococcus pyogenes (21%), moraxella catarhalis (8.3%), streptococcus pneumonia (8.3%) and Klebsiella pneumonia (4%). The quick clinical response, lack of major adverse drug reactions and susceptibility of the bacterial isolates to Roxithromycin were very significant attributes of the drug. In addition, there was complete recovery in 95.8% of the patients. Roxithromycin is therefore a well tolerated and effective drug for the treatment of acute respiratory tract infections in Nigerian patients.

Acute Disease↗
PubMed1998

Investigation of serum minimal inhibitory concentrations of some benzimidazole, imidazole and benzothiazole derivatives and their effects on liver and renal functions.

In previous studies many benzimidazole, imidazole and benzothiazole derivatives had been synthesized and their antimicrobial activities were tested in vitro conditions. Four of these compounds showed minimal inhibitory concentrations (MIC) of 5-25 micrograms/ml against standard strains and clinical isolates. In order to determine whether these four compounds can be used for therapeutic purpose, their serum MIC values and side effects on hepatic and renal functions were determined. Different concentrations of the compounds were tested on Wistar rats. Compound 1 was administered orally, intramuscularly and intravenously; compounds 2, 3 and 4 were given orally and intramuscularly. Blood samples were taken 4 and 24 h after administration of the compounds. Serum MIC values were investigated by bioassay and serum levels of biochemical parameters by autoanalyzer. None of the tested compounds showed antimicrobial activity at their serum concentrations. Although creatinine activity was found at normal levels in all experiments, compounds 1 and 2 caused a significant increase in blood urea nitrogen (BUN) level. The values of aspartate aminotransferase and/or alanine aminotransferase and/or alkaline phosphatase which are characteristic for liver function were generally found at high levels. According to these results, it can be concluded that the tested compounds caused damage in liver and biliary tracts without antimicrobial activity by their serum concentrations.

Animals↗
PubMed2006

Using soil health to assess ecotoxicological impacts of pollutants on soil microflora.

Microorganisms are essential for a properly functioning soil ecosystem. However, few methods allow an ecotoxicological evaluation of pollutant impact on the soil microbial community. This review proposes the use of the concept of soil health as an ecotoxicological evaluation tool for soil microflora. Initially limited to sustainable agriculture, the concept of soil health is now being applied to novel situations including contaminated and remediated soils. A large amount of work has been published in the last few decades on soil health indicators, and a review of the most relevant studies is presented here. The most cited work is that of the S-5518 committee set up in 1997 by the Soil Science Society of America (SSSA), which proposed to define soil quality as being "the capacity of a soil to function within the limits of an ecosystem, to support biological production, to maintain environmental quality and to support fauna and flora health." The soil health indicators reviewed here are the ones based on this definition because it relates well to sustainability and durability of the soil functions. Several indicators proposed in these studies could be employed in the evaluation of the ecotoxicological impact of pollutants on the soil microbial community, including microbial diversity, microbial activity, and functional stability. However, research is still required to unify the concept, to set threshold values, and to standardize methodologies.

Environmental Health↗
PubMed2006

Immune privilege in sites of chronic infection: Leishmania and regulatory T cells.

Leishmania are digenetic protozoan parasites that are inoculated into the skin by vector sand flies, are taken up by macrophages, and produce a spectrum of chronic diseases in their natural reservoir and susceptible human hosts. During the early establishment of infection in the skin and lymphoid organs, Leishmania produce multiple effects on macrophage and dendritic cell functions that inhibit their innate anti-microbial defenses and impair their capacity to initiate T-helper 1 cell immunity. In addition, the skin is a site preconditioned for early parasite survival by virtue of a high frequency of steady-state, natural CD25+Foxp3+ regulatory T cells (Tregs) that function to suppress the generation of unneeded immune responses to infectious and non-infectious antigens to which the skin is regularly exposed. In murine models of infection, antigen-induced CD25+/-Foxp3-interleukin (IL)-10+ Treg cells act during the effector phase of the immune response to control immunopathology and may also delay or prevent healing. Finally, following resolution of infection in healed mice, CD25+Foxp3+ Tregs function in an IL-10-dependent manner to prevent sterile cure and establish a long-term state of functional immune privilege in the skin.

Animals↗
PubMed2005

Risk/benefit assessments of human diseases: optimum dose for intervention.

A simple procedure is proposed in order to quantify the tradeoff between a loss suffered from an illness due to exposure to a microbial pathogen and a loss due to a toxic effect, perhaps a different illness, induced by a disinfectant employed to reduce the microbial exposure. Estimates of these two types of risk as a function of disinfectant dose and their associated relative losses provide information for the estimation of the optimum dose of disinfectant that minimizes the total expected loss. The estimates of the optimum dose and expected relative total loss were similar regardless of whether the beta-Poisson, log-logistic, or extreme value function was used to model the risk of illness due to exposure to a microbial pathogen. This is because the optimum dose of the disinfectant and resultant expected minimum loss depend upon the estimated slope (first derivative) of the models at low levels of risk, which appear to be similar for these three models at low levels of risk. Similarly, the choice among these three models does not appear critical for estimating the slope at low levels of risk for the toxic effect induced by the use of a disinfectant. For the proposed procedure to estimate the optimum disinfectant dose, it is not necessary to have absolute values for the losses due to microbial-induced or disinfectant-induced illness, but only relative losses are required. All aspects of the problem are amenable to sensitivity analyses. The issue of risk/benefit tradeoffs, more appropriately called risk/risk tradeoffs, does not appear to be an insurmountable problem.

Disease↗
PubMed2001

The impact of meconium ileus on the clinical course of children with cystic fibrosis.

The present study was designed to compare the clinical course of children diagnosed with cystic fibrosis (CF) in infancy due to the presence of meconium ileus (MI) with children diagnosed by way of a newborn screening programme (non-MI). A matched case-control study design was used. Matching was performed on the basis of sex and date of birth. All children born in New South Wales, Australia after 1980 and who had attended the CF clinic at The Children's Hospital at Westmead since diagnosis were included as possible cases or controls. Parameters pertaining to the clinical course were compared in 39 matched pairs. MI children had a significantly worse pulmonary status. The forced expiratory volume in one second was 16.3 +/- 5.2% higher (p<0.001, n=21 pairs) and the forced vital capacity value 10.5 +/- 4.7%, higher (p<0.05, n=21 pairs) in non-MI children. The difference between the pairs (18.6 +/- 4.4 MI and 20.5 +/- 3.4 non-MI) in the Shwachman chest radiograph score was statistically significant (p<0.05, n=39 pairs). There were no significant differences in any other assessed parameters, such as height, weight, the presence of liver function abnormalities, the frequency of hospitalization or airway microbial colonization. Meconium ileus may be an early indication of a more severe phenotype of cystic fibrosis. This was suggested by the significantly lower pulmonary function found in children with a history of meconium ileus compared to age- and sex-matched children who did not have meconium ileus.

Case-Control Studies↗
PubMed1990

Microbial stress proteins.

There is general agreement that a function, perhaps the major function, of stress proteins under normal physiological conditions is to help assembly and disassembly of protein complexes and to catalyse protein-translocation processes. It remains unclear, however, as to what role these processes play in stressed cells. It could be that cells under stress produce abnormal, misfolded or otherwise damaged proteins and that increased synthesis of stress proteins is required to counter protein modifications. A role for stress proteins in recovery of cells from stress, as opposed to a role in helping cells to withstand a lethal stress, is thus suggested. The intracellular location of stress proteins, in the unstressed and stressed cell, is worthy of further studies. Members of the hsp70 family are associated with the cytosol, mitochondria and endoplasmic reticulum. There is evidence, particularly from studies on mammalian cells (Tanguay, 1985; Welch and Mizzen, 1988; Arrigo et al., 1988), that following stress hsps migrate to various cellular compartments and subsequently delocalize after stress. However, there is little comparable data from microbial systems for this phenomenon (e.g. Rossi and Lindquist, 1989). The question as to the role of stress proteins in the transient acquisition of thermotolerance remains to be answered. It is insufficient to equate the kinetics of stress-protein synthesis with acquisition of thermotolerance. Quantitative data on the amount of stress protein present at various times, including the recovery period, is required. The demonstration that microbial stress proteins are important antigenic determinants of micro-organisms causing major debilitating diseases in the world is an exciting observation. Studies on the interplay of pathogen and host, both carrying similar antigenic hsp determinants, will be a challenging area for future research. It is likely that E. coli and Sacch. cerevisiae, with their well-established biochemical and genetic properties, will continue to be the experimental systems of choice for studies on stress proteins. On the other hand, it is encouraging that studies on other micro-organisms have expanded in the past few years and have made substantial contributions towards our understanding of the stress response. The ubiquitous nature of the stress response and the remarkable evolutionary conservation of the stress proteins continue to be attractive areas for research.

Bacterial Proteins↗
PubMed1991

Modeling of bacterial growth as a function of temperature.

The temperature of chilled foods is a very important variable for microbial safety in a production and distribution chain. To predict the number of organisms as a function of temperature and time, it is essential to model the lag time, specific growth rate, and asymptote (growth yield) as a function of temperature. The objective of this research was to determine the suitability and usefulness of different models, either available from the literature or newly developed. The models were compared by using an F test, by which the lack of fit of the models was compared with the measuring error. From the results, a hyperbolic model was selected for the description of the lag time as a function of temperature. Modified forms of the Ratkowsky model were selected as the most suitable model for both the growth rate and the asymptote as a function of temperature. The selected models could be used to predict experimentally determined numbers of organisms as a function of temperature and time.

Food Microbiology↗
PubMed2026

Deciphering the effects of sulfonamide antibiotics on denitrification from a metagenomic perspective: Inhibition of nitrite reduction and succession patterns of functional microorganisms.

Limited research has thoroughly elucidated the impact mechanisms of antibiotics on the denitrification process at the genomic and gene levels, which has hindered the optimization and development of nitrogen removal technology for antibiotic-containing swine wastewater. Lab-scale sequencing batch reactors were constructed in this study to treat synthetic wastewater containing different sulfonamides and nitrate. Investigations were carried out on denitrification performance, microbial community diversity, denitrifier succession patterns, and functional gene distribution. The stress of sulfonamides inhibited the nitrite reduction process, transforming complete denitrification into partial denitrification and causing significant nitrite accumulation. The average nitrogen removal efficiency in the treatment groups decreased from 81.0% &#xb1; 2.2-40.1% &#xb1; 6.1%. Alicycliphilus and Thauera were identified as the key taxa, accounting for 32.2% and 16.9% of all potential denitrifying bacteria, respectively. Although metagenome-assembled genomes (MAGs) from Thauera were enriched with genes encoding nitrate reductases (nap, nar) and nitrite reductases (nir), this genus preferentially utilized nitrate as an electron acceptor, resulting in the preferential nitrate reduction and subsequent nitrite accumulation. In contrast, Alicycliphilus MAGs developed tolerance to the sulfonamides stress during later stages, with concomitant enrichment of associated functional genes. They replaced Thauera to reemerge as the dominant group, thereby restoring complete denitrification. This study provides new insights into the regulatory mechanisms governing complete versus partial denitrification in nitrogen removal from antibiotic-containing wastewater.

Denitrifier succession↗