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PubMed2026

Characterization of the oral microbiota and antimicrobial resistance genes in shelter dogs in Japan.

Companion animals can serve as reservoirs of antimicrobial resistance genes and zoonotic microorganisms, yet information on shelter dogs remains limited. This study characterized the oral microbiota and screened for antimicrobial resistance genes in shelter dogs in Japan. Oral swabs were collected from 81 dogs, microbial genomic DNA was extracted, bacterial communities were profiled by 16S rRNA gene amplicon sequencing, and antimicrobial resistance genes were screened by PCR. We detected genes conferring resistance to several antimicrobial classes, including β-lactams, tetracyclines, macrolide-lincosamide-streptogramin B, phenicols, and sulfonamides. cfxA was detected in all 81 samples, followed by sul1 (66/81), tet(M) and sul2 (65/81), floR (39/81), mecA (17/81), and erm(B) (15/81). We identified potentially pathogenic genera including Capnocytophaga, Pasteurella, Fusobacterium, Campylobacter and Corynebacterium. Microbiome analysis revealed that at the phylum level, Pseudomonadota and Bacteroidota were the most dominant, while Porphyromonas, Frederiksenia and Moraxella were the most prevalent genera. Our findings highlight that (i) the oral microbiota of shelter dogs broadly resembles that reported in companion dogs and (ii) shelter dogs represent an overlooked reservoir of clinically relevant antimicrobial resistance genes and potentially zoonotic bacteria. Therefore, it is necessary to include shelter animals in antimicrobial resistance surveillance programs to capture any potential gaps in the antimicrobial resistance prevalence in companion animals and prevent dissemination of resistant bacteria to humans following adoption of shelter dogs and cats.

antimicrobial resistance gene↗
PubMed2004

Methicillin-resistant Staphylococcus aureus in horses and horse personnel.

Fortunately, MRSA infection and colonization are currently uncommon in veterinary medicine. Nevertheless, the increasing reports of the occurrence of MRSA infection in horses, veterinarians, and equine personnel dictate that serious consideration be given to the control of this pathogen in veterinary hospitals as well as in the equine community. It is unclear whether extrapolation from human hospitals and people in the community is appropriate; however, given the rapid increase in nosocomial MRSA in human hospitals and the recent shift of certain clones of MRSA into the community, it would be unwise to ignore this potential pathogen. If equine MRSA did, indeed, originate in the human population, complete eradication in the equine population is unlikely, regardless of the prevalence of infection in horses and the intensity of infection control measures, without concurrent eradication of MRSA in the human population, which is surely an impossible feat. Early institution of appropriate surveillance and other infection control measures should be used to attempt to limit the impact of MRSA in veterinary medicine, however. It has been stated, "The time to act is now, before the prevalence of MRSA in the community begins to rise and we end up with 50% of the community strains becoming methicillin-resistant". This statement was directed at control of MRSA in people; however, it is equally relevant in the veterinary context and should receive strong consideration.

Animals↗
PubMed1976

Incidence of Salmonella spp., Clostridium botulinum, and Vibrio parahaemolyticus in an estuary.

A study of the incidence of Salmonella spp., Vibrio parahaemolyticus-like organisms, and clostridium botulinum in samples collected at five stations located in the Upper Chesapeake Bay, a major estuary on the Atlantic Coast of the United States, was conducted in December 1973 through December 1974. C. botulinum types B and E were detected in 12.3% of the total sediment samples examined. V. parahaemolyticus was recovered from 10.4% of a total of 86 water, sediment, and suspended sediment samples. Of 131 samples examined for the presence of Salmonella spp., approximately 3% were found to be positive for serologically confirmed Salmonella isolates. Shellfish examined during the investigation were also found to be free of enteric pathogens. The low frequency of occurrence of V. parahaemolyticus was attributed to the low salinities encountered at the sites included in the study. A low incidence of Salmonella spp. in the Upper Chesapeake Bay samples was found, whereas the distribution of C. botulinum appeared to be both random and autochthonous. A strong relationship between presence of potential pathogens and other generally accepted microbiological indicators of pollution was not observed.

Animals↗
PubMed1983

Human Edwardsiellosis traced to ornamental fish.

Protracted diarrhea in a 2-month-old Belgian infant was associated with Edwardsiella tarda as the only potential pathogen. The same organism was isolated from a tropical aquarium fish in the home of the patient. The enteropathogenic role of E. tarda and the role of fish as a reservoir of infection are reviewed. Additional observations, volunteer studies, and careful prospective surveys in tropical countries will be needed to produce firm evidence of the enteropathogenic potential of E. tarda.

Animals↗
PubMed1996

Problems and priorities for controlling opportunistic pathogens with new antimicrobial strategies; an overview of current literature.

An International Study Group on New Antimicrobial Strategies (ISGNAS) has been formed in response to the recognition that development of microbial resistance to antibiotics is becoming a serious, world-wide problem. The group met in 1993 for the first time to discuss the feasibility of developing rational alternatives to the use of antibiotics and prepared, as a result, a comprehensive overview of normal (physiological) mechanisms involved in the control of potentially pathogenic (oppotunistic) microorganisms. One objective of ISGNAS is to understand the conditions which allow opportunistic microbes present among the symbionts to cause an infection. There is a need for more coherent information concerning the habitat, growth requirements and host and pathogen properties which allow opportunistic pathogens to cause life-threatening infections. In particular, information is urgently being sought to understand the complexity of the interactions between the vast number of microbial species, and the interactions between the microbes and their host. Another goal is to inspire and enable basic and clinical research that will lead to the development of new therapies for regulating colonization, translocation and infection by opportunistic micro-organisms in patients during periods of decreased resistance. With a sufficient amount of knowledge of how healthy individuals keep opportunistic micro-organisms under control, it may become feasible for physicians to maintain host resistance and inter-microbial factors involved in the containment of opportunistic microbes. Therapies aimed at boostering natural resistance mechanisms will be of critical importance to individuals whose resistance has been compromised as a result of another clinical condition.

Adjuvants, Immunologic↗
PubMed2006

Molecular mimicry: sensitization of Lewis rats with Campylobacter jejuni lipopolysaccharides induces formation of antibody toward GD3 ganglioside.

Recently we have reported cases of demyelinating inflammatory neuropathy showing elevated titers of anti-GD3 antibodies, which occurs rarely in Guillain-Barré syndrome. To examine the correlation between the anti-GD3 antibody titer and Campylobacter jejuni infection, we sensitized female Lewis rats with lipopolysaccharides (LPSs) from serotype HS19 of C. jejuni and examined changes in nerve conduction velocity and nerve conduction block (P/D ratio). After 16 weeks of sensitization, animals revealed decreases of nerve conduction velocity and conduction block (P/D ratio) and high titer of anti-GD3 antibodies. These anti-GD3 antibodies also blocked transmission in neuromuscular junctions of spinal cord-muscle cells cocultures. The GD3 epitope was verified to be located on the Schwann cell surface and nodes of Ranvier in rat sciatic nerve. To determine the target epitope for GD3 antibodies in causing nerve dysfunction, the LPS fraction containing the GD3 epitope was purified from the total LPS by using an anti-GD3 monoclonal antibody-immobilized affinity column. Subsequently, chemical analysis of the oligosaccharide portion was performed and confirmed the presence of a GD3-like epitope as having the following tetrasaccharide structure: NeuAcalpha2-8NeuAc2-3Galbeta1-4Hep. Our data thus support the possibility of a contribution of GD3 mimicry as a potential pathogenic mechanism of peripheral nerve dysfunction.

Animals↗
PubMed2003

Bacterial replacement therapy: adapting 'germ warfare' to infection prevention.

The individual bacterial members of our indigeneous microbiota are actively engaged in an on-going battle to prevent colonisation and overgrowth of their terrain by competing microbes, some of which might have pathogenic potential for the host. Humans have long attempted to intervene in these bacterial interactions. Ingestion of probiotic bacteria, particularly lactobacilli, is commonly practiced to promote well-balanced intestinal microflora. As bacterial resistance to antimicrobials has increased, so too has research into colonisation of human tissues with specific effector strains capable of out-competing known bacterial pathogens. Recent progress is particularly evident in the application of avirulent Streptococcus mutans to the control of dental caries, alpha hemolytic streptococci to reduction of otitis media recurrences and Streptococcus salivarius to streptococcal pharyngitis prevention.

Bacteria↗
PubMed1997

Antimicrobial activity of 12 broad-spectrum agents tested against 270 nosocomial blood stream infection isolates caused by non-enteric gram-negative bacilli: occurrence of resistance, molecular epidemiology, and screening for metallo-enzymes.

A total of 270 recent nosocomial blood stream isolates of non-Enterobacteriaceae Gram-negative bacilli representing nearly 50 U.S. medical centers were characterized. The numbers of isolates of individual organisms were: Pseudomonas aeruginosa (n = 204), Acinetobacter spp. (n = 48), and Stenotrophomonas maltophilia (n = 18). MICs were determined using the broth microdilution susceptibility method with 12 antimicrobial agents: piperacillin, piperacillin/tazobactam, ceftriaxone, ceftazidime, cefepime, imipenem, ciprofloxacin, ofloxacin, amikacin, gentamicin, tobramycin, and trimethoprim/sulfamethoxazole. Based on current National Committee for Clinical Laboratory Standards breakpoints, rates of resistance to cefepime, ceftazidime, and imipenem were as follows: P. aeruginosa, 3, 9, and 5%; Acinetobacter spp., 2, 37, and 0%; and S. maltophilia, 88.7, 35.3, and 100%, respectively. Trimethoprim/sulfamethoxazole was the most active agent against S. maltophilia (100% susceptible). Twenty-eight isolates of P. aeruginosa that expressed high levels of resistance to ceftazidime (MIC, > 256 micrograms/mL) and imipenem (MIC, > 32 micrograms/mL) were examined for potential metallo-beta-lactamase production by polymerase chain reaction and were found to be negative. Molecular typing of P. aeruginosa isolates revealed many patient-unique strains, but also noted clustering of infections due to isolates of the same DNA type, suggesting possible nosocomial transmission in 9 of 14 medical centers. Given the resistance profile and pathogenic potential of these non-enteric Gram-negative bacilli, considerable effort should be exerted to develop and enforce infection control and antimicrobial utilization practices that will limit the spread of these organisms in the hospital environment.

Acinetobacter↗
PubMed1999

The safety and usefulness of routine bronchoscopy before stem cell transplantation and during neutropenia.

Fibreoptic bronchoscopy with bronchoalveolar lavage (BAL) is used for clinical investigation and research into pulmonary complications of stem cell transplantation. Adverse effects of BAL are common in neutropenic patients with lung disease; there are few data on its safety when used routinely in transplant recipients without lung impairment. We describe the complications and usefulness for infection surveillance of routine BAL pre-transplantation and during neutropenia. Thirty-three patients before autologous or allogeneic BMT or PBSCT (B1) and 24 during post-transplant neutropenia (B2) underwent BAL; patients with pulmonary disease were excluded. Subjects were monitored for adverse effects, and BAL fluid was examined for pathogens. Complications of B2 were compared with events seen in 35 neutropenic patients who did not undergo BAL (C). Eighteen percent B1 and 33% B2 subjects showed complications of BAL. Fever occurred in 12% B1 and 26% previously afebrile B2 subjects, compared to 11% of C (P = 0.3). Epistaxis occurred in one B2 subject and two C. Potentially pathogenic organisms were isolated from 18% B1 and 13% B2 BAL fluids; none caused later respiratory infection. Bronchoscopy and BAL pre- and post-transplant had acceptable safety for a research procedure, but were not clinically helpful for infection surveillance.

Adolescent↗
PubMed1979

Chorioamnionitis and funisitis due to Corynebacterium kutscheri.

When isolated from the female genital tract, diphtheroids are usually regarded as commensal organisms. Corynebacterium kutscheri however is a pathogen in laboratory rodents. We report a case in which C. kutscheri was isolated as a pure culture from the umbilical cord and from other surface sites in an infant. Histological examination of the cord and membranes demonstrated the organisms within these fetal tissues. The organisms evoked a fetal cellular response. The importance of recognising commensals as potential pathogens in states of altered host resistance in stressed.

Corynebacterium↗
PubMed2003

Ceftriaxone (1 g intravenously) penetration into abdominal tissues when administered as antibiotic prophylaxis during nephrectomy.

A pharmacokinetics study was conducted to determine the effects of ceftriaxone administered before nephrectomy on the occurrence of postoperative wound infection. Ceftriaxone was administered as antibiotic prophylaxis in 11 consecutive patients undergoing nephrectomy who received 1,000 mg intravenously 30 min before surgery. Simultaneous blood and tissue samples were collected at three stages of the surgical procedure: opening of the abdominal cavity, nephrectomy, and closure of the abdominal cavity. Samples of following tissues were assayed: abdominal-wall fat, perirenal fat, kidney cortex and medulla, and urine. During the different stages of surgical procedures, ceftriaxone concentrations remained higher than the MIC90 of the potential pathogens (Staphylococcus aureus, Escherichia coli, and Enterobacteriaceae). In selected patients undergoing nephrectomy and requiring antimicrobial prophylaxis such as malnourished, debilitated, diabetic or immunosuppressed patients, the use of a single dose of ceftriaxone (1,000 mg) makes it possible to offer an optimal bacterial coverage for the prevention of postoperative infection. According to our kinetic evaluation, ceftriaxone is potentially a good antibiotic for prophylaxis in urological surgery.

Abdomen↗
PubMed2003

Colitogenic Th1 cells are present in the antigen-experienced T cell pool in normal mice: control by CD4+ regulatory T cells and IL-10.

CD4(+) regulatory T cells have been shown to prevent intestinal inflammation; however, it is not known whether they act to prevent the priming of colitogenic T cells or actively control these cells as part of the memory T cell pool. In this study, we describe the presence of colitogenic Th1 cells within the CD4(+)CD45RB(low) population. These pathogenic cells enrich within the CD25(-) subset and are not recent thymic emigrants. CD4(+)CD45RB(low) cells from germfree mice were significantly reduced in their ability to transfer colitis to immune deficient recipients, suggesting the presence of commensal bacteria in the donor mice drives colitogenic T cells into the Ag-experienced/memory T cell pool. This potentially pathogenic population of Ag-experienced T cells is subject to T cell-mediated regulation in vivo by both CD4(+)CD25(+) and CD4(+)CD25(-) cells in an IL-10-dependent manner. Furthermore, administration of an anti-IL-10R mAb to unmanipulated adult mice was sufficient to induce the development of colitis. Taken together, these data indicate that colitogenic Th1 cells enter into the Ag-experienced pool in normal mice, but that their function is controlled by regulatory T cells and IL-10. Interestingly, IL-10 was not absolutely required for CD4(+)CD25(+) T cell-mediated inhibition of colitis induced by transfer of naive CD4(+)CD45RB(high) cells, suggesting a differential requirement for IL-10 in the regulation of naive and Ag-experienced T cells.

Animals↗
PubMedDate not supplied

[Iron and infection].

Iron is essential nutrient for the growth of the most pathogenic microorganisms. However in vivo iron is complexed with host proteins such as transferrin in the blood and lactoferrin in secretions so that it is not available as a free ionic iron. Restriction in the availability of free iron in the host, the so-called nutritional immunity plays a key role in nonspecific defence strategy against potential pathogens. To overcome the lack of free iron, microorganisms produce substances that chelate iron and they are called siderophores. The outcome of every infection is therefore dependent on both the level of free iron present in the host and the efficiency of siderophore-mediated iron uptake system of the pathogen.

Bacteria↗
PubMed1986

Branhamella catarrhalis as a lower respiratory tract pathogen in patients with chronic lung disease.

To determine the possible role of Branhamella (formerly Neisseria) catarrhalis as a respiratory pathogen, we screened quality sputa (defined by cellular criteria) that showed numerous gram-negative cocci on Gram's stain for the presence of B catarrhalis. In an eight-month period, 52 isolates of B catarrhalis were identified in adults attending a hospital for chest diseases. During this period B catarrhalis was the third most common potential pathogen isolated from sputa. Twenty-two patients (42%) had associated patchy bronchopneumonic or lobar infiltrates. All had negative blood cultures and a generally mild clinical course. The majority of strains (73%) of B catarrhalis produced beta-lactamase and were resistant to penicillin and ampicillin. Isolates (including beta-lactamase-producing strains) were susceptible to erythromycin, tetracycline, and trimethoprim-sulfamethoxazole. These studies demonstrate that in patients with chronic lung disease, the presence of B catarrhalis in sputum can be suspected on the basis of a Gram's stain and may be associated with the development of new pneumonic infiltrates. Since these organisms frequently produce beta-lactamase, empiric antimicrobial therapy should include agents other than the penicillins.

Aged↗
PubMed2002

Rapidly growing mycobacterial pulmonary infection in association with severe gastroesophageal reflux disease.

Pulmonary infection due to rapidly growing mycobacteria (Runyan group IV) is uncommon and may be overlooked or misdiagnosed. Esophageal disorders have been recognized as a potential risk factor predisposing for this infection. A 35-year-old Sri Lankan patient, with severe gastroesophageal reflux disease and a hiatus hernia, contracted a pulmonary infection with Mycobacterium fortuitum-chelonae. He had severe airway obstruction and focal bronchiectasis, and responded to treatment with ciprofloxacin and clarithromycin. The case is reported to alert clinicians to the pathogenic potential of these organisms and to the prompt institution of appropriate chemotherapy once infection is recognized.

Adult↗
PubMedDate not supplied

Effects of the consumption of alcohol in the oral cavity: relationship with oral cancer.

In an epidemiologic point of view the consumption of alcoholic beverages is found to be associated to an increased risk for developing an upper gastrointestinal tract cancer. The relation of the studies that establish this connection is complicated due to both the confluence of various risk factors within the same person such as alcohol and tobacco, and to the lack of data that can be verifiable by the clinician. For this reason the exact pathogenic mechanism responsible for this increase of risk is not known since ethanol per se was not confirmed to be carcinogenic. Different hypotheses have been proposed, explaining how ethanol, by oral or systemic route, can act as a risk factor for the development of oral cancer. This article serves as a review of the actual situation of the potential pathogenic mechanisms, dividing them in local and systemic effects. Within the aforementioned special reference is made on the alteration of the oral mucosa permeability, the action of acetaldehyde and the role of retinoids.

Alcohol Drinking↗
PubMed1998

Detection of pathogenic Yersinia enterocolitica in enrichment media and pork by a multiplex PCR: a study of sample preparation and PCR-inhibitory components.

A multiplex PCR assay including sample preparation was developed to detect viable pathogenic strains of Yersinia enterocolitica in PCR-inhibitory samples, such as pork and enrichment media. The method developed was used to simultaneously detect the plasmid-borne virulence gene yadA and a Yersinia-specific region of the 16S rRNA gene. According to an auto-agglutination test for virulence-plasmid-bearing strains of Y. enterocolitica, all potential pathogenic strains tested were detected by the assay. A DNA extraction procedure, an aqueous two-phase system composed of polyethylene glycol 4000 and dextran 40 and a buoyant density centrifugation method, based on Percoll, were compared with regard to their efficiency in separating Yersinia enterocolitica from PCR inhibitors originating from enrichment media and pork. Using the density gradient centrifugation method resulted in a detection level of 4.0 x 10(2) CFU Y. enterocolitica per ml enrichment media. To ensure detection of viable bacteria a short enrichment step was included in the sample preparation together with the density gradient centrifugation. When this sample treatment method was evaluated with a selective enrichment medium together with a background flora inoculated with approximately 1.0 x 10(1) CFU per ml of Y. enterocolitica and incubated at 25 degrees C, a positive PCR result was obtained after 6 to 8 h. Our results indicate that selective enrichment followed by buoyant density gradient centrifugation provides a convenient and user-friendly sample preparation method prior to PCR.

Agglutination Tests↗
PubMed1995

Splenectomy as part of cytoreductive surgery for ovarian carcinoma.

Splenectomy is sometimes necessary to achieve optimal cytoreduction or manage iatrogenic injury in the surgical management of epithelial ovarian cancer (EOC) and related conditions. To determine the place of splenectomy in cytoreductive surgery a retrospective review was made of patient hospital records. Between April 1989 and August 1994, 18 patients were found to have undergone a splenectomy as a component of their surgery leading to optimal debulking. Morbidity attributable to the splenectomy was minimal, with no significant increase in operative time or blood loss. The morbidity attributable to the splenectomy was as follows: atelectasis and/or effusion (8), pancreatic tail injury (4), thrombocytosis > 10(6)/microliters (3), pancreatic pseudocyst (1), partial left adrenalectomy (1), and pulmonary embolism (1). There were no instances of overwhelming postsplenectomy infection. Five patients were anticipated to require splenectomy and may have benefitted from preoperative vaccination against potential pathogens. Three patients were found to have splenic parenchymal metastases. Consistent with the international literature, these patients had other features consistent with stage IV disease, recurrent disease, or poor survival. Consideration should be given to expanding the FIGO stage IV classification to include splenic parenchymal disease. Splenectomy is a feasible and safe procedure to facilitate optimal tumor debulking; however, the potential associated morbidity mitigates against this procedure if significant, suboptimal residual disease is left elsewhere.

Adult↗