Maximal amounts of prodigiosin were synthesized in either minimal or complete medium after incubation of cultures at 27 C for 7 days. Biosynthesis of prodigiosin began earlier and the range of temperature for formation was greater in complete medium. No prodigiosin was formed in either medium when cultures were incubated at 38 C; however, after a shift to 27 C, pigmentation ensued, provided the period of incubation at 38 C was not longer than 36 hr for minimal medium or 48 hr for complete medium. Washed, nonpigmented cells grown in either medium at 38 C for 72 hr could synthesize prodigiosin when suspended in saline at 27 C when casein hydrolysate was added. These suspensions produced less prodigiosin at a slower rate than did cultures growing in casein hydrolysate at 27 C without prior incubation at 38 C. Optimal concentration of casein hydrolysate for pigment formation by suspensions was 0.4%; optimal temperature was 27 C. Anaerobic incubation, shift back to 38 C, killing cells by heating, or chloramphenicol (25 gg/ml) inhibited pigmentation. Suspensions of washed cells forming pigment reached pH 8.0 to 8.3 rapidly and maintained this pH throughout incubation for 7 days. Measurements of viable count and of protein, plus other data, indicated that cellular multiplication did not occur in suspensions of washed cells during pigment formation. By this procedure utilizing a shift down in temperature, biosynthesis of prodigiosin by washed cells could be separated from multiplication of bacteria.
Viral respiratory infections are common causes of illness in infants and children. Examination of clinical specimens submitted for diagnosis during a 3-year period (August 1993-July 1996) at King Faisal Specialist Hospital and Research Center (KFSH & RC) in Riyadh revealed a wide spectrum of diseases associated with the isolation of five respiratory viruses. Severity of disease ranged from mild upper respiratory illness to threatening lower respiratory illnesses including bronchiolitis and pneumonia. Of the 256 isolates, respiratory syncytial virus (RSV) accounted for 73 (28.5%), adenoviruses for 70 (27.3%), influenza viruses for 61 (23.8%), enteroviruses for 39 (15.2%) and para-influenza for 13 (2.3%). Viruses were found more frequently in children attending emergency or paediatric wards than in outpatients. RSV appears in November and the seasonal peak occurs during January and February. Influenza activity begins in September and peaks in November and December. Para-influenza type I emerges in winter and para-influenza type III follows the influenza epidemic and may be detected sporadically in summer. The other viruses (enteroviruses, adenoviruses) were isolated throughout the year.
The efficacy and safety of oral fluconazole versus a polyene regimen in preventing mycoses in neutropenic patients was compared. Patients with haematological malignancy or bone marrow transplantation received as antifungal prophylaxis either fluconazole 200 mg daily or a regimen consisting of clotrimazole trouches 10 mg twice daily with mycostatin, 500,000 I.U. four times daily, benadryl and cepacol mouthwash. Ninety patients at risk for fungus infection were evaluable. Four of 42 patients (9.5%; confidence interval 2%-23%) on fluconazole and 17 of 48 patients (35.4%; confidence interval 22%-52%) (p < 0.01) on the clotrimazole regimen developed a clinically significant fungal infection, including 3 (7.1%) and 11 (22.9%) patients respectively who had severe fungal infection, mainly pulmonary aspergillosis. Death directly due to a fungal infection within 100 days of the start of prophylaxis occurred in 2 of 42 patients (4.8%) and 9 of 48 patients (18.8%) respectively (p < 0.06). Kaplan-Meier analysis showed that the chance of survival on fluconazole was statistically greater than for the clotrimazole regimen (p < 0.04). A decrease of candidal colonisation of the gastrointestinal and genitourinary tracts occurred only in patients receiving fluconazole. No significant toxicity occurred. A 200 mg daily dose of fluconazole given to these patients thus appears to be well tolerated and to provide a protective effect against the development of fungal infection and death from severe fungal disease.
To determine the causes of gastroenteritis at a major referral centre in Saudi Arabia, retrospective study was carried out on 58,110 fresh stools from 42,035 patients. Examination of stool specimens for pathogens was based on the clinical judgement of the physician responsible, so that all specimens were not tested for the presence of all pathogen groups. Bacterial enteropathogens were found in 7.7% of patients; Salmonella species (51.7%) were found to be the most frequent pathogens followed by Campylobacter jejuni (28%) and Shigella species (14.9%). Protozoan or metazoan parasites were detected in 27.8% of patients examined, the most common being Giardia lamblia and Hymenolepsis nana. Of the patients tested for viruses in stool, 14.1% had rotavirus, 5.3% adenovirus, 1.2% small round viruses and 0.3% coronavirus. Clostridium difficile toxin was also found in 9.5% of patients examined.
The effectiveness of treatment of human brucellosis caused by Brucella melitensis with ciprofloxacin alone was investigated in a prospective nonrandomized study. Subjects with central nervous system involvement, endocarditis, or severe renal dysfunction; children under 16 years of age; and pregnant women were excluded from the study. Of 19 patients, 16 completed the study; 7 were diagnosed as having acute systemic brucellosis, and 9 had acute brucella arthritis-diskitis. A rapid response to ciprofloxacin was seen in all 16 patients, but the blood cultures of 1 patient remained positive and the treatment was changed. During a 104-week follow-up period, 4 of the 15 responding patients relapsed or were reinfected within 8 to 32 weeks after completion of therapy. We conclude that treatment with ciprofloxacin alone, although effective for the acute symptoms, is associated with an appreciable rate of relapse; therefore, it should be given with other agents for treatment of brucellosis.Brucellosis is a common illness in developing countries. The disease remains hyperendemic in Kuwait, Saudi Arabia, and the Mediterranean region. This is due to the prevalence of infected domestic animals in these regions: camels, goats, and sheep. The most effective, least toxic chemotherapy for human brucellosis is still undecided. Brucella melitensis is susceptible to a wide variety of antibiotics. In Saudi Arabia, the MICs and MBCs of streptomycin, gentamicin, and netilmicin are similar but there is an appreciable gap between the MICs and the MBCs of rifampin, tetracycline, and trimethoprim-sulfamethoxazole.Brucella species are facultative intracellular parasites; therefore, it is important to treat patients with antimicrobial agents which penetrate macrophages and are bactericidal. Ciprofloxacin is a broad-spectrum synthetic fluoroquinolone which inhibits the growth of gram-positive and gram-negative bacteria. High oral bioavailability, high concentration in tissue, and rapid bacterial killing make it attractive for the treatment of intracellular infections (4, 10, 13). In vitro studies have shown that all clinical isolates of B. melitensis tested prior to therapy were susceptible to ciprofloxacin (3,6,14 Pharmacy and Therapeutics Committee and the ResearchCommittee approved the study prior to its inception.Patients with central nervous system involvement or endocarditis were excluded from the study. Individuals who had received antimicrobial therapy after recognition of the initial symptoms, pregnant women, those under 16 years of age, those allergic to nalidixic acid or its derivatives, and those with severe renal dysfunction were also excluded.The diagnostic criteria used were isolation of Brucella species from blood or other tissues or fluids or positive serology, i.e., total agglutinating antibodies (agglutination titer, 1:640) in the presence of compatible clinical findings. Patients initially seen with acute onset of fever, chills, sweating, and malaise with positive brucella serology or positive brucella culture were defined...
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