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M M Hill

Publications and source records attributed to M M Hill.

17 recordsLinked to original sources
PubMed1988

Phenotypic selection of small-colony variant forms of Staphylococcus epidermidis in the rat model of endocarditis.

Four pathogenic strains of Staphylococcus epidermidis (sensu strictu)-EC, RP62A, LW, and HBSN--exhibited a mixed population of colony phenotypes when plated onto a high-salt, low-glucose agar ("Memphis agar"). When compared with challenge inocula, significant shifts in colony populations to the small-colony variant forms occurred for all four strains for isolates recovered from infected vegetations of rats with catheter-induced endocarditis. Various colony phenotypes of the HBSN strain were compared in virulence studies by using the rat model of endocarditis. The infectivity rate of the small-colony variant forms was significantly less than that of either the normal parent form (P less than .05) or the mixed phenotypic inoculum (P less than .05). These data indicate that the small-colony variant forms may be selected for, once endocardial infections are established, and that the small-colony variant forms alone are much less able to initiate and/or sustain intracardiac infections in experimental endocarditis.

Animals↗
PubMed1988

Proposed virulence factors among coagulase-negative staphylococci isolated from two healthy populations.

Proposed virulence factors, including multiple antibiotic resistance and slime-mediated adherence, among coagulase-negative staphylococci colonizing healthy individuals from two different study populations were examined. Resistance to methicillin was more commonly seen than initially anticipated. In addition, adherence characteristics, as quantitated by a microtiter plate method, were very similar to those of strains of coagulase-negative staphylococci causing nosocomial infections.

Bacterial Adhesion↗
PubMed1986

Effects of exercise training during hemodialysis.

Fourteen maintenance hemodialysis patients volunteered to participate in a 6-month program of exercise training. The exercise was performed on a stationary bicycle during the hemodialysis treatment. Six maintenance hemodialysis patients served as control without exercise training. Exercising patients participated in 91% of all possible exercise sessions. The exercise group showed a significant (23%) increase in maximal oxygen consumption over the 6 months. No change in exercise capacity resulted in the control group. Five of eight hypertensive patients in the exercise group decreased or discontinued antihypertensive medications. No changes occurred in hematocrit or lipid profiles in either group. We conclude that exercise training during the hemodialysis treatment is technically feasible and safe for appropriately screened patients and will increase exercise capacity, and in some patients improve blood pressure control. Exercise during dialysis also improves compliance to regular exercise and facilitates supervised exercise sessions, which are desirable in this patient group.

Antihypertensive Agents↗
PubMed1970

Sex and gender.

Explore the source record for details and available documents.

Adolescent↗
PubMedDate not supplied

Antimicrobial prophylaxis of experimental endocarditis caused by Staphylococcus epidermidis.

Using two different strains of Staphylococcus epidermidis in a rat model of experimental endocarditis, we examined the prophylactic efficacy of cefamandole (200 mg/kg/dose), cefazolin (200 mg/kg/dose), nafcillin (200 mg/kg/dose), and vancomycin (20 mg/kg/dose). In vitro susceptibility testing demonstrated that both test strains were resistant to methicillin and cefazolin and susceptible to cefamandole and vancomycin. A 10(6) cfu inoculum was used for both strains, an inoculum which produced endocardial infections in greater than 90% of rats. Initial doses of each antibiotic were given 45 min to 1 h prior to bacterial challenge and were followed by six additional doses of each antibiotic administered subcutaneously every 6 h. The efficacy rates of cefamandole (84.0%) and cefazolin (70.8%) were exactly the same for rats infected with either S. epidermidis strain. Similar efficacy rates were seen in rats infected with either strain and treated with vancomycin (94.4% and 86.7%). Unlike the other three drugs, the efficacy of nafcillin was quite different in rats challenged with the two strains (62.5% and 38.5%, p = 0.19). It appears that cefamandole and cefazolin may have considerable prophylactic efficacy against certain infecting strains of methicillin-resistant, coagulase-negative staphylococci when relatively large doses of cephalosporins are administered subcutaneously in this animal model.

Animals↗
PubMedDate not supplied

Differences in CT findings within schizophrenics may be due to varying severity of the illness.

The authors investigated the importance of severity and duration of illness in schizophrenia with regard to findings on computerised tomographic (CT) scans. Two groups are compared, one from a state hospital's chronic ward and the other group from a university hospital. They provide evidence to propose increased ventricular size is an indicator of severity of illness.

Adult↗