Search PubMed⌕ Search

Biomedical subjects

M F Rein

Publications and source records attributed to M F Rein.

At least 37 records · Page 2Linked to original sources
PubMed1983

Beta-hemolytic activity of Trichomonas vaginalis correlates with virulence.

The reasons that some women develop symptomatic trichomonal vaginitis, whereas many other infected women remain asymptomatic, are unclear, but it has been suggested that Trichomonas vaginalis strains vary in their intrinsic virulence. We describe beta-hemolytic activity in T. vaginalis which correlates with virulence in patients as well as in an animal model and in tissue culture. Fresh T. vaginalis isolates from four women with severe, symptomatic trichomoniasis had high-level (86.3 +/- 6.6%) hemolytic activity, whereas isolates from three completely asymptomatic women had low-level (45.3 +/- 8.4%) hemolytic activity (P less than 0.001). Hemolytic activity also correlated with the production of subcutaneous abscesses in mice (r = 0.74) and with destruction of CHO cell monolayers (r = 0.94). All of the 20 clinical isolates of T. vaginalis tested possessed hemolytic activity. The beta-hemolysin may be a virulence factor for T. vaginalis.

Animals↗
PubMed1982

Zinc sensitivity of Trichomonas vaginalis: in vitro studies and clinical implications.

The high zinc concentration (2.3-15.3 mM) in human prostatic secretions may be an important defense of the male lower urinary tract against infection by Trichomonas vaginalis. Trichomonads were rapidly killed by zinc salts at concentrations similar to those in prostatic fluid of normal men. There was some variation in the zinc sensitivity of 15 clinical isolates of T. vaginalis (minimal inhibitory concentration, 0.8-6.4 mM). A time-kill technique showed subtle differences in the kinetics of zinc killing of trichomonad strains. It was possible to select relatively zinc-resistant substrains of T. vaginalis from a zinc-sensitive population. Zinc resistance was a stable characteristic after multiple passages of substrains in growth medium without supplemental zinc. Variations in the zinc sensitivity of infecting T. vaginalis strains or in the zinc content of host prostatic secretions may be significant determinants of the natural history of T. vaginalis infection in men.

Animals↗
PubMed1982

Canine prostatic secretions kill Trichomonas vaginalis.

The zinc content of prostatic secretions is thought to be an important nonspecific defense against urinary tract infection in men. This investigation measured killing by prostatic fluid of Trichomonas vaginalis, a common sexually transmitted pathogen, and related this activity to zinc concentration. We used a canine model which closely resembles the human male genital tract. Prostatic secretions from all dogs killed all T. vaginalis isolates. There appear to be several mechanisms for killing of trichomonads by prostatic fluid. At prostatic fluid zinc concentrations comparable to those in normal men (greater than or equal to 3.2 mM), the rate of killing of trichomonads was proportional to the zinc concentration. At intermediate zinc levels, killing occurred by both zinc-dependent and zinc-independent mechanisms. A zinc-independent mechanism was responsible for antitrichomonal activity at relatively low zinc levels (less than 1.6 mM), comparable to those in the prostatic fluid of men with chronic prostatitis. This study suggests that the variable clinical spectrum of trichomoniasis in men may result from a balance between the zinc sensitivity of the T. vaginalis strains on one side and the content of both zinc and zinc-independent factors in prostatic fluid on the other.

Animals↗
PubMed1981

Treatment of vulvovaginal candidiasis with boric acid powder.

A double-blind comparison was made of the use of 14 daily intravaginal gelatin capsules containing 600 mg of boric acid powder versus the use of identical capsules containing 100,000 U nystatin diluted to volume with cornstarch for the treatment of vulvovaginal candidiasis albicans. Cure rates for boric acid were 92% at 7 to 10 days after treatment and 72% at 30 days, whereas the nystatin cure rates were 64% at 7 to 10 days and 50% at 30 days. The speed of alleviation of signs and symptoms was similar for the two drugs. There were no untoward side effects, and cervical cytologic features were not affected. In vitro studies found boric acid to be fungistatic and its effectiveness to be unrelated to pH. Blood boron analyses indicated little absorption from the vagina and a half-life of less than 12 hours. Acceptance by the patients was better than for "messy" vaginal creams, and self-made capsules containing boric acid powder are inexpensive (31 cents for fourteen) compared with the costly medication commonly prescribed.

Adult↗
PubMed1980

Gonococcal tenosynovitis-dermatitis and septic arthritis. Intravenous penicillin vs oral erythromycin.

Twenty-three patients with disseminated gonococcal infections--15 with acute tenosynovitis, six with septic monoarticular arthritis, and two with both--were randomly given five days of erythromycin stearate or estolate, 500 mg orally every six hours (13 patients), or crystalline aqueous penicillin G potassium, 1 million units intravenously every three hours for three days (ten patients). There were no treatment failures. Cultures taken one and seven days and two and four weeks after completion of therapy were uniformly negative. Clinical resolution was rapid in both groups, as judged by response of fever, joint tenderness, and disappearance of joint effusion. Orally administered erythromycin is a useful alternative to penicillin in the treatment of disseminated gonococcal infections, particularly in penicillin-allergic pregnant women.

Administration, Oral↗
PubMed1980

Trichomonacidal activity of human polymorphonuclear neutrophils: killing by disruption and fragmentation.

Polymorphonuclear neutrophils (PMNs) were shown to kill Trichomonas vaginalis in vitro; 10(2)-10(3) trichomonads were incubated with 3 x 10(6) PMNs on tissue culture plates, and surviving organisms were enumerated in pour plates. After 60 min of aerobic incubation at 37 C, 100% (+/- 0) of the trichomonads had been killed, and nitroblue tetrazolium was reduced at the interface between the PMNs and trichomonads. The importance of oxidative microbicidal systems was confirmed by the observations that only 12% +/- 12% of trichomonads were killed under anaerobic conditions and that aerobic killing was eliminated by the addition of catalase or superoxide dismutase. PMNs killed trichomonads in fresh or absorbed serum but not in bovine serum albumin, in heat-inactivated serum, or in the presence of 1 mM trypan blue; this finding suggested a role for alternative pathway activation of complement. Phase-contrast cinemicrography and electron microscopy revealed the pursuit and surrounding of individual trichomonads by groups of PMNs that were able to fragment the large protozoa and to phagocytize the pieces.

Animals↗
PubMed1980

Sulfamethoxazole-trimethoprim synergism for Neisseria gonorrhoeae.

Sulfamethoxazole and trimethoprim are synergistic against many bacteria in sulfamethoxazole/trimethoprim concentrations of 20:1, but single-dose therapy of gonorrhea with the combination is disappointing. We used agar dilution techniques to determine minimal inhibitory concentrations of sulfamethoxazole and trimethoprim for 168 gonococci isolated from men with acute urethritis in Atlanta, Ga. The geometric mean minimal inhibitory concentrations were 5.6 microgram of sulfamethoxazole per ml and 24.3 microgram of trimethoprim per ml, a ratio of 1:4. The concentration of sulfamethoxazole inhibiting 50% of gonococcal strains dropped only from 4.7 microgram/ml to 2.9 microgram/ml with the addition of a 1/20 dilution of trimethoprim. We studied synergism with various ratios of sulfamethoxazole to trimethoprim against 20 random strains. A ratio of 1:1 was always synergistic and was the most synergistic ratio for 15 strains, whereas the 19:1 ratio was never the most syngergistic. The 19:1 ratio failed to show synergism against seven strains, but showed antagonism at this ratio with five of these seven. The sulfamethoxazole/trimethoprim ratio of 19:1 usually achieved in serum after oral administration is minimally syngergistic and is sometimes antagonistic for gonococci.

Drug Synergism↗
PubMed1978

Accuracy of Gram's stain in identifying pneumococci in sputum.

We prospectively examined the accuracy of Gram-stained sputum for identifying pneumococci in 42 patients with community-acquired pneumonia. We considered the Gram's stain positive if a preponderant flora or more than ten Gram-positive lancet-shaped diplococci were seen per oil immersion (x1,000) field. These criteria were met in 18 (62%) of 29 specimens that actually contained pneumococci as determined by a positive quellung reaction, or culture on plates or in mice. The Gram's stain was negative in 11 of 13 specimens that did not contain pneumococci. Of the 20 specimens yielding positive Gram's stains, 18 contained pneumococci. A positive Gram-stained smear of sputum strongly suggests the presence of pneumococci, but will miss 38% of specimens containing pneumococci. Deviation from these criteria substantially reduces the overall accuracy of the test.

Acute Disease↗
PubMed1977

Treatment of gonorrhea with trimethoprim-sulfamethoxazole.

The following regimens were randomly administered to 271 men with gonococcal urethritis: 4.8 X 10(6) units of aqueous procaine penicillin G intramuscularly plus 1 g of probenecid orally (APPG); nine tablets of trimethoprim-sulfamethoxazole (TMP-SMZ; 720 mg of TMP and 3,600 mg of SMZ), orally as a single dose (TMP-SMZ-9); and 12 tablets of TMP-SMZ (960 mg of TMP and 4,800 mg of SMZ) orally as two doses of six tablets taken at a 6-hr interval (TMP-SMZ-12). The failure rates of the APPG, TMP-SMZ-9, and TMP-SMZ-12 regimens were 4%, 23%, and 19%, respectively. APPG was significantly more effective (P less than 0.05) than TMP-SMZ-9 or TMP-SMZ-12. Isolates of Neisseria gonorrhoeae from treatment failures as compared to those from treatment successes were significantly more resistant to SMZ (P less than 0.01) and to the TMP-SMZ combination in a ratio of 19 parts SMZ to one part TMP (P less than 0.05). Minimal inhibitory concentrations of SMZ, TMP, TMP-SMZ, and penicillin G showed positive correlation coefficients.

Administration, Oral↗