A rare case of centric fission and fusion in a river buffalo (Bubalus bubalis, 2n = 50) cow with reduced fertility.

A 5-year-old river buffalo cow underwent cytogenetic investigation since it had only one male offspring, apparently with normal body constitution, which died one month after birth. The female carrier had normal body conformation and internal sex adducts, as revealed by rectal palpation performed by a specialist veterinary practitioner. The cow was found to carry a complex and rare chromosome abnormality. Indeed, a centric fission of one river buffalo (BBU) chromosome 1 with a subsequent (or simultaneous) centric fusion of BBU1p with BBU23 was revealed by both RBA-banding and specific molecular markers of BBU1p (DEFB1) and BBU23 (ACTA2). CBA-banding revealed a pale, very small C-band in the der1 (BBU1q) and a prominent C-band on the new biarmed chromosome originated by rob(1p;23). Both telomeric probes and AgNOR staining confirmed the Robertsonian translocation (rob), both FITC-signals and the NORs (BBU23) being telomerically located. Furthermore, telomeric signals on der1 (BBU1q) indicate that these 2 chromosomal events may be the result of a reciprocal translocation which occurred between BBU1 and BBU23.

Nosocomial transmission clusters and risk factors in Moraxella catarrhalis.

We report an objective examination of nosocomial transmission events derived from long-term (10-year) data from a single medical centre. Cluster analysis, based on the temporal proximity of genetically identical isolates of the respiratory pathogen Moraxella catarrhalis, identified 40 transmission events involving 33 of the 52 genotypes represented by multiple isolates. There was no evidence of highly transmissible or outbreak-prone genotypes. Although most clusters were small (mean size 3.6 isolates) and of short duration (median duration 25 days), clustering accounted for 38.7% of all isolates. Significant risk factors for clustering were multi-bed wards, and winter and spring season, but bacterial antibiotic resistance, manifested as the ability to produce a beta-lactamase was not a risk factor. The use of cluster analysis to identify transmission events and its application to long-term data demonstrate an approach to pathogen transmission that should find wide application beyond hospital populations.

Bioelectrical impedance analysis for the prediction of fat-free mass in buffalo calf.

The objective of this study has been to develop a prediction equation of fat-free mass (FFM) from buffalo calves. Twenty buffaloes were fed ad libitum access at unifeed, with vitamin-mineral integration, for 14 months. Seven days before slaughtering, the animals were weighed and bioelectrical impedance measurements were collected. The data were analyzed by multiple linear regressions to evaluate the relationship between FFM and various predictor variables. Stepwise regression was used to eliminate variables that did not influence variation in the model. The value of resistance collected showed a decrease when the electrical frequency increases, while the values of reactance (Xc) increase. When using live weight (LW) and reactance at 500 and at 1000 kHz as independent variables, we obtained the best R2 Adj (0.967) and Durbin Watson statistic (2.596) that explain the prediction model (FFM = - 30.59 + 0.993LW + 0.150Xc500 - 0.123Xc1000 + 9.11). These results indicate that the use of bioelectrical impedance analysis has excellent potential as a rapid method, with minimal perturbation for the animal, to predict FFM in buffalo.

An outbreak of infections caused by non-typeable Haemophilus influenzae in an extended care facility.

Nosocomial outbreaks of infection due to non-typeable Haemophilus influenzae (NTHi) are rarely described. There are a few published reports that suggest that elderly patients with underlying pulmonary disease are at risk and that person-to-person spread is key to disease transmission. During the summer months of 2005, we documented an outbreak of NTHi infections in a Veterans Affairs nursing home. Thirteen patients developed conjunctivitis or lower respiratory infection involving a beta-lactamase-negative biotype III NTHi isolate, with an indistinguishable SmaI macrorestriction pattern. Patients were elderly males usually with underlying cardiac and pulmonary disease. A case-control study failed to demonstrate any specific significant risk factor for NTHi infection and there was no evidence of spatial clustering of cases within the nursing home. A random throat culture survey involving nursing home patients during the outbreak showed that only one of 19 persons was colonized with NTHi. The outbreak concluded following appropriate treatment and an emphasis on universal and respiratory droplet precautions. All patients recovered and a specific inciting event for the outbreak was never defined. Literature review revealed a spectrum of responses to nosocomial NTHi infections and a lack of consensus regarding the infection control approach towards NTHi outbreaks.

The accumulation of alpha-Tocopherol and Retinol in the milk of water buffalo is correlated with the plasma levels of triiodothyronine.

Milk is the most important source of Retinol and alpha-Tocopherol for calves. These antioxidants save the food quality and prevent lipid oxidation in the mammary gland and the calf growing tissues. In Bubalus bubalis, seasonal changes for the plasma levels of both antioxidants were not found. The levels of Retinol and alpha-Tocopherol in the milk were 2 and 1.7 times higher in winter than in summer, respectively. These levels were correlated with the plasma level of triiodothyronine, and markedly increased in cows injected with triiodothyronine in summer. The cytosol from alveolar epithelial cells of mammary glands was incubated with alpha-Tocopherol and 3H-Retinol and, after gel filtration chromatography, both antioxidants were found associated with proteins migrating as a single peak of 33 kD. The amount of alpha-Tocopherol and Retinol binding proteins was 1.5 and 2.3 times higher in winter than in summer respectively. The Retinol binding proteins migrated as two bands (33 and 16 kD) by electrophoresis in denaturing and reducing conditions. Our data suggest that triiodothyronine enhances the transport of both liposoluble antioxidants through the blood-mammary barrier, and demonstrate that proteins of the mammary epithelial cells are involved in such a transport.

A pericentric inversion in the cattle Y chromosome.

Sixteen male Podolian cattle, two sires and their 14 male offspring, were investigated cytogenetically on the basis of a female-like phenotype found in one of them. Eleven male offspring, including the one with female traits, and one of the two sires were found to carry an abnormal Y chromosome which originated from a pericentric inversion of the proximal half of the Yq arm (Yq11-->q12.2), as demonstrated by both banding and FISH mapping techniques with Y-specific molecular markers.

The epidemiology of mupirocin resistance among methicillin-resistant Staphylococcus aureus at a Veterans' Affairs hospital.

OBJECTIVE: To describe the clinical and molecular epidemiology of mupirocin-resistant (MR) and mupirocin-susceptible (MS) methicillin-resistant Staphylococcus aureus (MRSA) at a Veterans' Affairs hospital and to assess risk factors associated with the acquisition of MR MRSA. DESIGN: All clinical MRSA isolates for the period October 1990 through March 1995 underwent susceptibility testing to mupirocin. Mupirocin resistance trends were measured, and MS MRSA and MR MRSA isolates underwent typing by pulsed-field gel electrophoresis (PFGE). A retrospective case-control study was conducted to evaluate risk factors for having MR versus MS MRSA. SETTING: The James H. Quillen Veterans' Affairs Medical Center in Mountain Home, Tennessee, included a 324-bed acute-care hospital, a 120-bed nursing home, and a 525-bed domiciliary. Colonizations and infections with MRSA were endemic, and mupirocin ointment was commonly used. PATIENTS: Inpatients and outpatients at the facility. RESULTS: MS MRSA was recovered from 506 patients and MR MRSA from 126. Among MR MRSA isolates, 58% showed low-level mupirocin resistance (minimum inhibitory concentration [MIC] > or = 4 to 256 microg/mL), and 42% showed high-level mupirocin resistance (MIC > or = 512 microg/mL). A significant increase (P=.002) in the number of high-level MR isolates occurred during the 1993 to 1995 period. A case-control study showed that presence of a decubitus ulcer correlated with high-level resistant isolates (P<.05). The distribution of PFGE patterns did not differ for MR and MS MRSA CONCLUSIONS: Use of mupirocin ointment in a program aimed at managing endemic MRSA infection or colonization resulted in a significant increase in the recovery of high-level MR MRSA isolates. These isolates appeared to emerge from our existing MRSA pool. A case-control study provided few clues concerning patients likely to harbor MR MRSA. We confirmed the position that the extended use of mupirocin ointment should be avoided in settings where MRSA is endemic.

The cardiovascular and metabolic complications of HIV infection.

With the advent of more effective therapies for human immunodeficiency virus (HIV) infection, HIV-infected patients are living longer and cardiovascular disease is becoming more obvious in this population. Patients with HIV infection represent one of the most rapidly developing groups with cardiovascular disease globally. Cardiovascular disease complicating HIV infection is likely to contribute to burgeoning healthcare costs. Pericarditis, myocarditis, cardiomyopathy, atherosclerotic coronary vasculopathy, arterial aneurysms, pulmonary hypertension, and endocarditis occur with increased frequency in these patients. Pericardial tamponade, dilated cardiomyopathy, endocarditis, and vasculopathy can lead to fatal outcomes in this population. The advent of cardiomyopathy heralds a very poor prognosis in patients infected with HIV. Coronary vasculopathy without obvious risk factors can lead to myocardial ischemia in young patients infected with the virus. Moreover, the protease inhibitors used to treat HIV infection induce a syndrome of lipodystrophy and dyslipidemia that may be associated with accelerated atherosclerosis as well as insulin resistance. All these factors contribute to increased cardiovascular morbidity and mortality in the HIV-infected population. HIV infection, opportunistic infections, secreted viral proteins such as gp120 (envelope protein) or Tat (transactivator of viral transcription), and cytokines elaborated during the course of HIV infection of the immune system all contribute to pathogenesis of these disorders. Further basic and clinical studies are required to understand the pathogenesis of cardiovascular complications and develop appropriate management strategies for these patients.

Blastomycosis in northeast Tennessee.

STUDY OBJECTIVES: To study the epidemiologic and clinical features of blastomycosis in northeast Tennessee. DESIGN: Retrospective review of blastomycosis cases in the region from 1980 through 1995. SETTING: Hospitals located in the Tri-Cities region of northeast Tennessee. PATIENTS: Seventy-two patients with confirmed blastomycosis infection. INTERVENTIONS: None. RESULTS: During the 1980 to 1995 study period, we documented 72 cases of blastomycosis. The mean age was 52 years (range, 13 to 86 years), most were male (69.4%), and nine were immunocompromised. A possible environmental exposure was noted for 28 patients. Pulmonary involvement represented the most common site of infection (61 cases), but multiorgan involvement was common (17 cases). Most patients with pulmonary blastomycosis (66%) presented with a chronic illness, and radiologic findings usually revealed local consolidation or a mass-like lesion. Nine patients developed ARDS with an associated mortality rate of 89%, compared with a 10% mortality for non-ARDS pulmonary cases. Antifungal treatment regimens varied widely, with amphotericin B often used for sicker patients. An epidemiologic evaluation revealed that the mean yearly incidence rate for blastomycosis quadrupled between 1980 and 1987 (0.31 cases/ 100,000 population) and 1988 to 1995 (1.23 cases/100,000 population) (p=0.00001). Most new blastomycosis cases in the 1988 to 1995 period occurred in three counties in the region where significant new construction projects have been underway. CONCLUSION: Blastomycosis is endemic in northeast Tennessee and the number of cases is increasing, coinciding with major new construction in the region. Clinicians in the area must be alert to this condition.

Spinal epidural abscess associated with the use of temporary epidural catheters: report of two cases and review.

Spinal epidural abscess has rarely been associated with the use of epidural catheters. We describe two patients with epidural abscesses that occurred in relation to the use of temporary epidural catheters; a literature review yielded 20 additional well-described cases. The mean age of these 22 patients was 49.9 years, the median duration of epidural catheter use was 3 days, and the median time to onset of clinical symptoms after catheter placement was 5 days. The majority of patients (63.6%) had major neurological deficits, and 22.7% also had concomitant meningitis. Staphylococcus aureus was the predominant pathogen. Despite antibiotic therapy and drainage procedures, 38% of the patients continued to have neurological deficits. These unusual but serious complications of temporary epidural catheter use require efficient and accurate diagnostic evaluation, as they can be substantial.

Susceptibility of antibiotic-susceptible and antibiotic-resistant hospital bacteria to disinfectants.

OBJECTIVE: To evaluate whether hospital strains of antibiotic-resistant bacteria exhibited altered susceptibility to disinfectants. DESIGN: Antibiotic-susceptible bacteria were obtained from American Type Culture Collection: Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Klebsiella pneumoniae, Salmonella choleraesuis, and Pseudomonas aeruginosa. Hospital strains of antibiotic-resistant bacteria were obtained from clinical isolates, including: S aureus, S epidermidis, E coli, Enterococcus species, K pneumoniae, and P aeruginosa. The Association of Official Analytical Chemist's use-dilution method was used to test these 12 strains of 7 bacterial pathogens for their susceptibility to a phenol and a quaternary ammonium compound. For five pathogens, we tested a susceptible and a more resistant strain in 20 comparative trials (5 pathogens, 2 disinfectants, 2 dilutions per disinfectant). RESULTS: In our 20 comparative trials, the antibiotic-resistant strains exhibited an increased resistance to the disinfectant in only a single instance. CONCLUSIONS: Our data demonstrate that the development of antibiotic resistance does not appear to be correlated to increased resistance to disinfectants.

Enterococcal meningitis: report of four cases and review.

Enterococci, a significant cause of human infections outside of the CNS, have only rarely been documented to cause meningitis. To add to our understanding of this uncommon infectious process, we report our experience with four patients with enterococcal meningitis and summarize findings associated with 28 additional cases found in the medical literature. The majority of the adult patients with this condition had coexistent chronic underlying illnesses and were frequently exposed to immunosuppressive therapy. In addition, more than one-third of these patients had experienced CNS trauma or surgery, and 31% had an infection with enterococci at a site other than the CNS. Pediatric patients predominantly had underlying CNS pathology primarily consisting of neural tube defects or hydrocephalus. Primary meningitis occurred in 25% of pediatric patients, with most of these episodes occurring in neonates. Most patients presented with expected signs, symptoms, and physical features of acute bacterial meningitis and had typical CSF abnormalities, including leukocytic pleocytosis, elevated protein levels, and hypoglycorrhachia. The overall mortality rate among patients with enterococcal meningitis was 13%. The small number of patients in this review failed to demonstrate a definite difference in mortality among patients treated with cell wall-active agents alone vs. those treated with combination therapy with an aminoglycoside, although studies of patients with other complicated enterococcal infections suggest that combination therapy would be preferable.

Comparative activity of meropenem (SM-7338) against major respiratory pathogens and amikacin-resistant nosocomial isolates.

Meropenem, a new broad-spectrum carbapenem antibiotic, demonstrated excellent in vitro activity against major respiratory pathogens including Moraxella catarrhalis, Haemophilus influenzae and Streptococcus pneumoniae. Minimal inhibitory concentrations of meropenem for Moraxella catarrhalis and Haemophilus influenzae isolates were frequently less than those of imipenem. For nosocomial amikacin-resistant gram-negative bacilli, meropenem had eightfold lower MIC90 values compared to imipenem against strains of Serratia marcescens, Enterobacter cloacae and Escherichia coli; it was 32-fold more active than imipenem against Proteus mirabilis isolates. Activity was similar to that of imipenem against Pseudomonas aeruginosa isolates. Overall, meropenem showed excellent activity against common community-acquired pathogens as well as amikacin-resistant nosocomial pathogens.

Randomized comparative study of cefixime versus cephalexin in acute bacterial exacerbations of chronic bronchitis.

Patients with purulent exacerbation of chronic bronchitis were randomized to receive either a single 400-mg daily dose of cefixime or 250 mg of cephalexin, orally, four times a day. Patients were males with a mean age of 63 years. Of the 86 patients, 71 (82%) had bronchitis caused by a single organism (29 by Haemophilus influenzae, 27 by Branhamella catarrhalis, 9 by gram-negative enteric organisms, 6 by Streptococcus pneumoniae), while more than one pathogen was implicated in 15 patients (18%). A total of 70.8% of the cefixime group and 50% of the cephalexin group were clinically cured (chi 2 = 3.89, P less than 0.05); however, when the categories of cured and improved were combined, no significant difference was noted between treatment groups (chi 2 = 3.39, P = 0.06). Analysis of side effects included all 130 evaluable and nonevaluable patients: diarrhea was noted in six patients in the cefixime group and none of the patients in the cephalexin group (P = 0.013 by the Fisher exact test). The diarrhea was mild and self-limited in all cases. B. catarrhalis has emerged as a major cause of exacerbation of bronchitis in our experience; there is an increased need to emphasize the examination of sputum samples by Gram staining if cost-effective antibiotic choices are to be made; any empirically chosen antibiotic should have activity against beta-lactamase-producing strains of B. catarrhalis as well as S. pneumoniae and H. influenzae.

Respiratory infections caused by Branhamella catarrhalis. Selected epidemiologic features.

PURPOSE: This work reviewed existing literature pertaining to the epidemiologic aspects of respiratory tract infections caused by Branhamella catarrhalis, examined certain epidemiologic features of B. catarrhalis infections occurring at this facility, and identified relevant areas in need of further study. PATIENTS AND METHODS: Literature dealing with the epidemiology of B. catarrhalis infections was reviewed. Records in this Veterans Administration hospital microbiology laboratory were reviewed and all B. catarrhalis isolates and pure cultures of Hemophilus influenzae and Streptococcus pneumoniae were noted for the January 1986 to June 1989 study period. RESULTS: B. catarrhalis is now recognized as a disease-causing pathogen that is particularly noted for its association with acute otitis media in children and lower respiratory tract infections in adults with underlying cardiopulmonary disease. It was recovered from 2.7 percent of all respiratory specimens submitted over a 42-month period at this Veterans hospital. When compared with H. influenzae and S. pneumoniae, B. catarrhalis was found to be the second most commonly isolated respiratory pathogen. It was frequently found in pure culture (53 percent) or in combination with H. influenzae, gram-negative bacilli, or S. pneumoniae. The seasonal recovery of B. catarrhalis was apparent for the November to May period compared with the June to October period (p less than 0.001). CONCLUSION: B. catarrhalis has emerged as a major respiratory pathogen in pediatric and adult patient populations. There is a distinct seasonal pattern associated with its recovery and reasons for this are unclear. Prevalence studies aimed at identifying colonization rates among "low" and "high" risk groups are needed. The availability of restriction endonuclease analysis as a typing system for B. catarrhalis should favorably impact upon future epidemiologic studies. Many B. catarrhalis isolates produce beta-lactamase, and therapeutic options must reflect this.

Corynebacterium xerosis as a cause of vertebral osteomyelitis.

We report a patient who developed Corynebacterium xerosis vertebral osteomyelitis 6 months following a decompressive laminectomy. Prolonged parenteral and subsequent oral therapy for 11 months resulted in apparent cure. This is the first reported case of vertebral osteomyelitis caused by C. xerosis.

Urbs in rure: human immunodeficiency virus infection in rural Tennessee.

Although the AIDS Commentaries published over the past 18 months have focused on clinical questions relevant to all practicing infectious diseases physicians, they have emphasized clinical information gathered from the large epicenters of the epidemic. We need to remember that clinicians dealing with HIV-infected patients outside metropolitan areas may face problems that are unique. For example, fighting the stigma of AIDS in a low-prevalence population may be as important an issue as treating pneumocystic pneumonia. In this AIDS Commentary, Drs. Abraham Verghese, Steven L. Berk, and Felix Sarubbi of the Veterans Administration Medical Center, East Tennessee State University and describe their experiences in such an environment, discuss some of the problems they've faced, and offer suggestions about what physicians and health officers need to do to prepare for the inevitable spread of AIDS to rural communities.

Epidemiology of tuberculosis in North Carolina, 1966 to 1986: analysis of demographic features, geographic variation, AIDS, migrant workers, and site of infection.

We analyzed all cases of tuberculosis reported in North Carolina between 1966 and 1986, and related the incidence rate of tuberculosis (per 100,000 population) to age (0 to 4 years, 7.59; 5 to 14 years, 3.44; 15 to 24 years, 6.30; 25 to 44 years, 15.92; 45 to 64 years, 33.85; greater than 65 years, 51.54), race (white 9.03, nonwhite 47.40), and gender (male 25.49, female 11.25). Over the 21-year study period the annual number of cases declined from 1,248 to 711 (43%), and the incidence rate from 25.56 to 11.25 (56%). Although the incidence rate of tuberculosis fell for all subgroups, nonwhites continued to have an incidence rate 3.2 to 22.5 times higher than whites, depending on age. The standardized morbidity ratio (SMR) (by age, race, and gender) of tuberculosis in the eastern region of North Carolina was nearly twice that of the western region and unexplainable by its demographics. Between 1983 and 1986 only a small percentage of cases of tuberculosis in North Carolina were accounted for by migrant farm workers (1.7% to 2.7%) and patients with the acquired immunodeficiency syndrome (less than 1%). Tuberculosis is increasingly a disease of the elderly, especially nonwhite men. Tuberculosis is a geographically and demographically focal disease in North Carolina, and preventive strategies should be appropriately targeted.