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Results for “Potentially pathogenic bacteria”

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At least 19 recordsLinked to original sources

PubMed1977

Fiberoptic bronchoscopy and culture bacteria from the lower respiratory.

Forty-five specimens were obtained by sequential translaryngeal aspiration and fiberoptic bronchoscopy from 31 clinically unifected patients with lung cancer in order to evaluate the reliability of routine fiberoptic bronchoscopy for culture of the lower respiratory tract. Bacteria were recovered brom 98 percent (44) of the specimens obtained via fiberoptic bronchoscopy and from 58 percent (26) of the specimens obtained by the preceding translaryngeal aspiration. The microorganisms grown from cultures of specimens obtained by fiberoptic bronchoscopy consisted of mixtures of both nonpathogenic and potenitally pathogenic bacteria. Potentially pathogenic bacteria were present in 87 percent (39) of the specimens from fiberoptic bronchoscopy and 31 percent (14) of specimens from translayngeal aspiration. The results of cultures from the two procedures agreed completely in only a single instance. Culture of washings or secretions obtained by routine fiberoptic bronchoscopy is not recommended because it provides inaccurate and clinically confusing information about the presence or types of bacteria in the lower respiratory tract prior to instrumentation.

Aged↗

PubMed1978

Colonization resistance against potentially pathogenic bacteria in hexaflora-associated gnotobiotic mice.

A study of colonization resistance against potentially pathogenic bacteria (Escherichia coli and Pseudomonas aeruginosa) was conducted in hexaflora-associated gnotobiotic mice. Groups of germfree AKR mice were swabbed with five bacterial and a single gastrointestinal yeast species: Streptococcus faecalis. Lactobacillus brevis. Staphylococcus epidermidis, Enterobacter aerogenes, Bacteroides fragilis var. vulgatus, and Torulopsis sp. All species became established in the gut in 8 weeks. Later these associated mice were divided and challenged by four graded doses of E. coli or P. aeruginosa. The presence of challenge organism was monitored specifically in the freshly voided fecal specimens of the challenged mice. Escherichia coli colonized the gut of each mouse at each level up to 60 days post challenge. Pseudomonas aeruginosa was completely eliminated from each mouse at each dose level after 30 days post challenge. Evidence suggests that all six species were sufficient to prevent the colonization of P. aeruginosa and not of E. coli in the gut of the gnotobiotic mice.

Animals↗

PubMed1975

Secondary ocular bacterial infection in hypovitaminosis a xerophthalmia.

Extraocular bacterial culture was performed in 100 patients with hypovitaminosis A xerophthalmia. There was corneal ulceration in 29 cases and corneal perforation in 22 cases. Eighty-six percent of the patients harbored frankly pathogenic bacteria (46 patients) and potentially pathogenic bacteria (40 patients). All but two patients with either cornal ulceration or perforation harbored potentially pathogenic or frankly pathogenic bacteria. Pseudomonas aeruginosa, Diplococcus pneumoniae, and Moraxella species were isolated in 37% (19 patients) of cases with corneal ulceration and perforation. I cultured P. aeruginosa from 36% (eight patients) of cases with corneal perforation. The many ocular secondary bacterial infections in the early stages of xerophthalmia seem to suggest that bacterial action plays a major role in causing the corneal ulceration and perforation in hypovitaminosis A xerophthalmia.

Adolescent↗

PubMed2024

Filamentous bacteria-induced sludge bulking can alter antibiotic resistance gene profiles and increase potential risks in wastewater treatment systems.

Sludge bulking caused by filamentous bacteria is a prevalent issue in wastewater treatment systems. While previous studies have primarily concentrated on controlling sludge bulking, the biological risks associated with it have been overlooked. This study demonstrates that excessive growth of filamentous bacteria during sludge bulking can significantly increase the abundance of antibiotic resistance genes (ARGs) in activated sludge. Through metagenomic analysis, we identified specific ARGs carried by filamentous bacteria, such as Sphaerotilus and Thiothrix, which are responsible for bulking. Additionally, by examining over 1,000 filamentous bacterial genomes, we discovered a diverse array of ARGs across different filamentous bacteria derived from wastewater treatment systems. Our findings indicate that 74.84% of the filamentous bacteria harbor at least one ARG, with the occurrence frequency of ARGs in these bacteria being approximately 1.5 times higher than that in the overall bacterial population in activated sludge. Furthermore, genomic and metagenomic analyses have shown that the ARGs in filamentous bacteria are closely linked to mobile genetic elements and are frequently found in potentially pathogenic bacteria, highlighting potential risks posed by these filamentous bacteria. These insights enhance our understanding of ARGs in activated sludge and underscore the importance of risk management in wastewater treatment systems.

Sewage↗

PubMed2026

Unveiling microbial risks in Chinese household dust: a comprehensive analysis from absolute abundance to virulence unit.

BACKGROUND: People spend the majority of their lives indoors, yet the risk and virulence potential of household microbiota remain largely unexplored, particularly in developing countries. RESULTS: Here, we conducted a nationwide survey on both dust samples and health information across 118 Chinese households. The microbiota composition and its functional units were analyzed using absolute 16S rRNA/ITS sequencing, metagenomics, and metaproteomics. Cross-domain network analysis of the core microbial communities revealed robust co-occurrence patterns in household dust. The mean absolute abundance of potentially pathogenic bacteria and fungi in households was 2.39 × 105 and 2.83 × 106 DNA copies/g dust. The potentially pathogenic community was primarily influenced by latitude, relative humidity, and average temperature. Although total absolute abundance was substantially lower in urban areas, the relative abundance of potentially pathogenic bacteria was markedly higher compared to rural environments. While urban-rural differences existed, the underlying statistical drivers were the environmental variables. The absolute abundance of potential pathogens was significantly associated with the prevalence of rhinitis, wheeze, and dermatitis in 266 participants. Children were identified as the highest-risk group from inhalation exposure of average daily dose. A total of 170 bacterial, 223 fungal virulence factors (VFs), and 370 antibiotic resistance genes (ARGs) were detected in dust and dust extracellular vesicle (EV)-associated DNA. EV-associated cargoes contributed 47.13% to the bacterial VF profiles, 11.90% to fungal VF profiles, and 44.45% to ARG profiles. Metaproteomic analysis confirmed the presence of VF profiles in dust EVs, which was further verified by curated proteomics data from 35 household pathogens. CONCLUSIONS: This study provides a comprehensive, quantitative framework linking indoor microbial exposure to health risks, highlighting EVs as a non-negligible, novel, extracellular mechanistic pathway for health impact in household environments. Video Abstract.

Child↗

PubMed2026

Spiramycin fermentation residue-derived biochar regulates soil nutrient cycling, microbial communities, and antibiotic resistance gene dynamics.

Spiramycin fermentation residues (SFR) are hazardous wastes enriched with residual antibiotics, yet they can serve as potential feedstocks for resource recovery after appropriate treatment. In this study, SFR-derived biochar (SFR-BC) was produced by pyrolysis and applied to agricultural soil to evaluate its effects on soil properties, microbial communities, potential pathogenic bacteria, antibiotic resistance genes (ARGs), and mobile genetic elements (MGEs). A 60-day soil incubation experiment was conducted with one control and three SFR-BC application rates of 0.5%, 1.0%, and 2.0%. SFR-BC improved soil physicochemical properties, nutrient status, enzyme activities, and microbial alpha diversity. Metagenomic analysis showed that SFR-BC altered the abundance of functional genes associated with carbon and nitrogen cycling, indicating shifts in microbial functional potential. SFR-BC also changed bacterial co-occurrence patterns, with the high-dose treatment showing a more complex and highly connected network structure during incubation. In addition, high-dose SFR-BC reduced several potential pathogenic bacteria, including major plant pathogenic taxa. SFR-BC decreased soil ARG abundance by 9.38%-33.67% and MGE abundance by 6.49%-27.89% relative to the control, showing a dose-dependent reduction in antibiotic resistance-related genetic elements. Network and PLS-PM analyses further indicated that ARG variation was statistically associated with soil physicochemical properties, microbial diversity, potential bacterial hosts, and MGEs. Overall, these results suggest that SFR-BC can improve short-term soil nutrient status and reduce ARGs, MGEs, and several potential pathogenic taxa under controlled incubation conditions, providing useful evidence for the potential valorization of antibiotic fermentation residues through pyrolysis.

Charcoal↗

PubMed2026

Dynamics of antibiotic resistance genes co-occurrence with pathogenic and non-pathogenic bacteria throughout wastewater treatment processes.

Wastewater treatment plants (WWTPs) are recognized hotspots for antibiotic resistance genes (ARGs) and pathogenic bacteria. Despite advancements in treatment technologies, the persistence of ARGs and pathogenic bacteria remains a concern. In this study, we analyzed the dynamic changes in ARGs and bacterial communities throughout the treatment processes within an anaerobic-anoxic-oxic (AAO) WWTP over one week by using HT-qPCR coupled with 16S rRNA gene amplicon sequencing. The connectedness index, based on network analysis, showed that the dynamics of ARGs and mobile genetic elements (MGEs) were more strongly associated with potentially pathogenic bacteria than with non-pathogenic bacteria, suggesting that ARG immigration and dissemination in the WWTP were likely driven by potentially pathogenic taxa. The AAO treatment significantly reduced ARGs in final effluent (EF) (∼64 %) and residual sludge (RS) (∼81 %); however, potential hosts of ARGs such as Comamonas testosteroni and Clostridioides difficile persisted with minimal changes in relative abundance and remained detectable in EF and RS. Notably, the abundance of ARGs was lower in RS than in EF, and source tracking analysis identified influent as the primary source of ARGs and potentially pathogenic taxa in EF, underscoring the greater health risks associated with effluent discharge.

Wastewater↗

PubMed1976

[Maceration of the interdigital spaces and gram-negative infection of feet].

The microbiological flora of the macerated skin of the interdigital spaces of the feet of 64 patients were compared to those of 64 other control patients who had normal toe webs. In the control group coagulase-negative staphylococci and aerobic corynebacteria ("diphtheroids") were the most common bacteria found compared to a great number of different organisms including a high percentage of potentially pathogenic bacteria and fungi that were isolated from the macerated toe webs. The clinical appearance was not helpful in suggesting the nature of the causative organism. In order to prevent therapeutical errors bacteriological and mycological cultures are necessary before treatment.

Candida↗

PubMed1992

Handwashing and disinfection of heavily contaminated hands--effective or ineffective?

Hands are among the principal vehicles for transfer of nosocomial pathogens in hospitals. Often, outbreaks of infection are thought to be caused by a lack of compliance with handwashing guidelines, rather than due to the inadequacy of the handwashing agents used. In this study the effectiveness of proper handwashing and the use of three different hand disinfectants: ethanol 70% (E), isopropanol 40% (I) and alcoholic chlorhexidine (70%) (AC) was compared using three volunteers whose fingertips were heavily contaminated with a succession of bacteria including: Enterococcus faecalis, Staphylococcus aureus, Escherichia coli and Enterobacter cloacae. After each contamination, thorough handwashing and application of one disinfectant on the hands were performed three times. Fingerprint-samples were taken before and 1 min after application of the disinfectants. Thorough handwashing with an ordinary liquid soap ('Sterisol') did not reduce the confluent growth of bacteria on fingertips for any of the species used (197 examinations). Only AC had a significant effect on fingers heavily contaminated with S. aureus (126 examinations; AC compared with E and I; P less than 0.0002 and P less than 0.0002 respectively), but did not completely eradicate the bacteria. After contamination with Ent. cloacae (118 examinations), none of the three agents were particularly effective, but E and AC seemed to be somewhat more effective than I (P less than 0.0002 and P less than 0.01 respectively). When successive contamination was performed using all bacterial species, AC was the most effective decontaminant. However, Ent. cloacae was still present on the fingertips after 15 repeated courses of handwashing and applications of disinfectants. Bathing of hands in AC for 20s completely eradicated all bacteria from the hands. The study demonstrates that, when heavily contaminated, an ordinary handwashing followed by disinfectants is not enough to eradicate potentially pathogenic bacteria from the hands.

1-Propanol↗

PubMed1975

Bacteria in flower vase water: incidence and significance in general ward practice.

Culture of flower vase water from wards in the David Lewis Northern Hospital, Liverpool, revealed large numbers of potentially pathogenic bacteria. The types of organisms isolated may reflect the particular ecology of this hospital as they differed in some ways from those reported from other centres. The incidence of wound infections during the period of study was low (5-2 per cent) despite the regular overgrowth of bacteria in flower vases, and there did not appear to be any definite correlation between the types of bacteria isolated from flower vase water and those responsible for wound infections. The addition of hydrogen peroxide to flower vases proved a very effective antiseptic and is recommended for general use as a precautionary measure.

Cross Infection↗

PubMed1979

Aerobic and anaerobic bacterial flora of the maternal cervix and newborn gastric fluid and conjunctiva: a prospective study.

Aerobic and anaerobic cultures were performed on cervical swabs from 35 mothers and their newborn infants' gastric aspirates and conjunctival sacs. Four hundred seventy-nine isolates were obtained; 287 were aerobes and 192 were anaerobes. The cervical and gastric cultures overall yielded a similar flora, but this was not always the case when one compared mothers with their own newborn infants. The conjunctival cultures yielded about half of the number of bacteria per specimen that the gastric contents yielded, and a repeat conjunctival culture done 48 hours later showed a marked reduction in the number of potentially pathogenic bacteria isolated. The predominant aerobes isolated were Staphylococcus epidermidis, diphtheroids, viridans streptococci and Haemophilus vaginalis. The predominant anaerobes were the Bacteroides fragilis group, Propionibacterium acnes, Peptococcus, other Bacteroides and Peptostreptococcus organisms. Statistical analysis revealed significant positive correlation between the isolation of certain groups of organisms and increased duration of pregnancy, increased baby's weight, and prolonged duration of labor.

Bacteria↗

PubMed1992

The housefly (Musca domestica) as a carrier of pathogenic microorganisms in a hospital environment.

Houseflies have long been regarded as potential carriers of microorganisms. Since pathogenic microorganisms are widespread in the hospital environment, there is abundant opportunity for flies to become contaminated and, in turn, to contaminate the patient environment. In the present study, an attempt was made to isolate and identify pathogenic bacteria, fungi and parasites from the housefly Musca domestica collected in the surgical ward of the All India Institute of Medical Sciences Hospital and also in a remote residential area located 5 km from the hospital. A total of 113 flies were collected: 65 from a surgical ward (test) and 48 from a residential area for comparison. Ten genera of bacteria were isolated from the test group of flies compared with nine from the control group. In primary isolations, it was observed that the load of bacteria carried by the test group of flies was significantly more (P less than 0.001) than for the control flies. Pseudomonas aeruginosa, Enterococcus faecalis and viridans streptococci were isolated only from the test flies. The isolation rate of Staphylococcus aureus was significantly higher (P less than 0.001) in test houseflies than in the control houseflies. There was no significant difference in isolation of parasitic ova and cysts from test and control houseflies. Candida spp. were isolated in almost equal numbers from both groups of houseflies, yet none of these was Candida albicans. Houseflies therefore may act as vectors of potentially pathogenic bacteria in a hospital environment.

Animals↗

PubMed1979

The prevention of wound infections in burn patients.

To investigate the necessity of "protective isolation" and/or gastrointestinal tract decontamination in the prevention of infections in burn patients treated under ward conditions, a bacteriological inventory of burn sites, oropharynx and faeces was made 3 times a week. The origin of bacteria isolated from the lesions was determined by typing. In addition, the effect of local protection by topical application of silver-sulphadiazine or nitrofuralum was investigated. Of potentially pathogenic bacteria known to cause infections in burn, St. aureus was found to be almost exclusively exogenous in origin. Str. pyogenes, on the other hand, appeared either to be strongly inhibited by topical treatment or else to have colonized the wounds only from endogenous sources. Endogenous (gi-tract) Enterobacteriaceae biotype-positive samples were restricted to burn sites near the mouth and the anus. Enterobacteriaceae biotypes of exogenous origin appeared to colonize wounds of about one third of the patients. It is concluded that topical protection is insufficient in the prevention of bacterial colonization of the lesions. Therefore, protective isolation (St. aureus, etc.) and selective gastrointestinal decontamination are to be considered for infection prevention.

Bacterial Infections↗

PubMed1992

Role of human microflora in health and disease.

The human host and its microbial flora constitute a complex ecosystem whose equilibrium serves as a remarkable example of reciprocal adaptation. Intestinal bacteria play an important role in the development of the immune system. The normal intestinal flora is responsible for resistance to colonization by exogenous pathogenic microorganisms. Nevertheless, it also constitutes a reservoir of potentially pathogenic bacteria in close contact with the host. These bacteria are responsible for opportunistic infections in immunocompromised hosts. The equilibrium of the flora can be upset by antibiotics, leading to infections as a result of proliferation of antibiotic-resistant pathogenic bacteria.

Animals↗

PubMed1979

The nitroblue tetrazolium (NBT) reduction of neutrophil granulocytes from newborn infants and their mothers in relation to the occurrence of bacteria in amnion fluid and cord blood.

The nitroblue tetrazolium (NBT) reduction of granulocytes from cord blood, when measured without in vitro stimulation with bacteria, was significantly higher than that of maternal granulocytes. This elevated activity may be an adequate response to the presence in cord blood of degradation products from the placenta but also of potentially pathogenic bacteria, found in cord blood of infants with high NBT values. On in vitro stimulation cord blood granulocytes displayed the same high NBT activity as those of the mothers and of healthy non-pregnant women. All but one blood culture from the infants 25--48 h after delivery were sterile. The only child with a low non-stimulated NBT activity of cord blood granulocytes was also the only one presenting a clinical picture of neonatal septicemia, though not bacteriologically verified.

Adult↗

PubMed1978

A survey of rotavirus associated with gastroenteritis in Aboriginal children in Western Australia.

In a year-long survey which was carried out between April, 1975, and March, 1976, faecal specimens from Aboriginal and some non-Aboriginal children who suffered from gastroenteritis were examined by electron microscopy for rotavirus, and also tested for bacteria and parasites. The children were under six years of age and came from all parts of Western Australia, except Perth. Rotaviruses, "astroviruses" and adenoviruses were detected as well as the usual potentially pathogenic bacteria and parasites. Two peaks of rotavirus incidence were found during the year in specimens from Kalgoorlie, but only one peak occurred in Derby. Rotavirus was somewhat more frequently seen in non-Aboriginal than Aboriginal children.

Age Factors↗

PubMed1979

Purulent ocular discharge in neonates: significance of Chlamydia trachomatis.

We obtained cultures for bacteria and chlamydiae from 100 infants with conjunctivitis that began during the first month of life. Sixty-nine infants were evaluated during well-child visits (group A); 31 were seen specifically for the ocular discharge (group B). Potentially pathogenic bacteria, predominantly Staphylococcus aureus, were cultured from one third of the infants in each group. Chlamydia trachomatis was recovered from three infants (4%) in group A and from ten (32%) in group B. Three infants with chlamydial conjunctivitis (two in group A, one in group B) had only mild inflammation. Initial treatment with topical antibiotics was unsuccessful in eliminating the organism from seven of 11 infants.

Conjunctivitis↗

PubMed1978

Use of gentamicin to prevent intestinal side effects of lincomycin therapy.

Mild to severe and persisting diarrhea and even colitis have been reported as a side effect of therapy with lincomycin and clindamycin. An alteration in the normal bowel flora with an overgrowth of coliforms and other antibiotic-resistant bacteria has been postulated as a mechanism for the development of diarrhea. Investigations were undertaken in men to observe whether the simultaneous administration of gentamicin was capable of preventing lincomycin-associated intestinal disturbances. Of the 30 subjects treated only with lincomycin 11 (36.6%) developed diarrhea. Of the 18 subjects treated with lincomycin and simultaneously with oral gentamicine, none developed diarrhea. Results of bacteriological examinations indicate that in subjects treated with lincomycin, some potentially pathogenic bacteria, like coliforms and clostridia, are still present in intestinal flora; the simultaneous absence of bifidobacteria and bacteriodes could result in the abolishment of the host resistance to the noxious activity of these endogenous bacteria, as some reported data of the literature suggest. Coliforms and the majority of clostridia strains are not present in subjects treated simultaneously with gentamicin.

Adult↗