In vivo administration of antibody to interleukin-5 inhibits increased generation of eosinophils and their progenitors in bone marrow of parasitized mice

Bone marrow of mice parasitized with Nippostrongylus brasiliensis showed increased numbers of eosinophils as early as 4 days after infection. By day 7, their bone marrow also contained elevated numbers of progenitors that form small eosinophil colonies (20 to 50 cells) in soft agar cultures supplemented with interleukin-5 (IL-5). However, when mice were infused with anti-IL-5 antibodies at the time of infection, the number of recognizable eosinophils present in bone marrow remained low and eventually dropped below normal levels. The antibody treatment also prevented increased generation of IL-5- responsive precursors capable of differentiating into mature eosinophils in liquid culture and inhibited the generation of progenitor cells capable of forming small eosinophil colonies or clusters in soft agar cultures. The results of these in vivo experiments directly show that IL-5 is an essential regulatory molecule required for the bone marrow-dependent phase of a parasite-induced eosinophilia.     

The etiology of anorectal infections in homosexual men

The infectious etiology of symptomatic anorectal disease was studied in 52 homosexual men who did not have gonococci on initial Gram stain of anorectal exudate. Herpes simplex virus (HSV) was isolated from the anal canal or rectum in 15 of the 52 (29 percent) men and characteristically caused severe anorectal pain and focal ulcerations visible on sigmoidoscopy. Despite negative initial Gram stains, seven men (14 percent) had anorectal gonococcal infection. Six (12 percent) had syphilis, including two with dark-field positive anal lesions. Four were infected with enteric pathogens, including Giardia lamblia, Entamoeba histolytica or Campylobacter fetus ssp. jejuni. Chlamydia trachomatis (LGV 2 strain) was isolated from one patient with severe granulomatous proctitis. One or more etiologic pathogens were identified in 28 (67 percent) of 42 men who had anorectal leukocytic exudate and in two of 10 who did not (p = 0.01). A review of the prominent features of different etiologic forms of anorectal infection in homosexuals is presented.     

Cryptic structural lesions in refractory partial epilepsy: MR imaging and CT studies

Results of contrast material-enhanced computed tomography (CT) and T2-weighted spin-echo magnetic resonance (MR) imaging were correlated with pathologic findings in 25 patients treated surgically for refractory partial epilepsy. Of 12 lesions present, ten (83%) were detected by MR imaging and seven (58%) by CT scanning. Of nine low-grade gliomas, eight were detected by MR imaging and four by CT scanning. One posttraumatic scar and one case of temporal lobe atrophy were better demonstrated by MR imaging. A small, thrombosed arteriovenous malformation was the only lesion detected by CT scanning but not by MR imaging. No lesions were detected in 13 patients with mild gliosis and one patient with a 1.2-cm grade 1 astrocytoma. Although more sensitive than CT for detection of structural lesions in patients with refractory partial epilepsy, MR imaging resulted in a 25% false-negative diagnostic rate when a repetition time of 2,000 msec and echo time of 60 msec were used. Multi-echo imaging with at least one long echo time may be needed to increase the sensitivity of MR imaging in these patients.     

Rotator cuff sonography: a reassessment

This study is both a retrospective and prospective evaluation of the clinical usefulness of shoulder sonography. Ninety-eight patients suspected of having rotator cuff tears underwent sonography of both shoulders. Sixty-two patients underwent double-contrast arthrography performed on the same day as sonography, and 38 patients underwent surgery after sonography. A comparison of the results from ultrasound and arthrography, using published diagnostic criteria, demonstrated a sensitivity of 75% and a specificity of 43% for detection of a rotator cuff tear. In this study, use of more restricted criteria, a subset of the published criteria, yielded a sensitivity of 68% and a specificity of 90%. A comparison of sonography with surgery, using this study's criteria, demonstrated a sensitivity of 57% and a specificity of 76%. This report shows that shoulder sonography is less reliable than previously reported and appears to have a very limited role in the evaluation of rotator cuff injuries.     

Ondansetron--the first of a new class of antiemetic agents.

The chemistry, pharmacokinetics, adverse effects, stability, compatibility, and dosage of ondansetron hydrochloride are described, and clinical studies of the use of ondansetron for the prophylaxis of nausea and vomiting induced by antineoplastic therapy are reviewed. Ondansetron hydrochloride is a specific antagonist of serotonin type 3 (5-HT3) receptors, both in the chemoreceptor trigger zone and in the GI tract. Peak plasma concentrations of ondansetron occur approximately one hour after an oral dose and 6 to 20 minutes after an i.v. dose. The mean elimination half-life is approximately 3.5 hours in healthy volunteers, but it is extended in elderly patients (mean of 7.9 hours). In clinical trials, ondansetron has been shown to provide excellent control of nausea and vomiting in patients treated with cisplatin. Comparisons of ondansetron with metoclopramide in patients treated with various types of chemotherapy have shown better response rates with ondansetron. Ondansetron has also been shown to be effective in controlling nausea and vomiting in patients receiving cyclophosphamide with an anthracycline and in patients receiving combination therapy with cyclophosphamide, methotrexate, and fluorouracil. Adverse effects appear to be mild and include headache, constipation, diarrhea and transient abnormalities in liver function tests. The dose of ondansetron (as the hydrochloride salt) for the prophylaxis of chemotherapy-induced nausea and vomiting in adults is 0.15 mg/kg i.v. every four hours for three doses, beginning 30 minutes before antineoplastic therapy. The efficacy of ondansetron is comparable to that of metoclopramide, and the adverse-effect profile is much less problematic. The cost of ondansetron is much higher than that of metoclopramide; thus its use should be limited to patients at high risk for metoclopramide-induced adverse effects and patients in whom metoclopramide is ineffective.     

Retrospective evaluation of piperacillin use in a university hospital.

A retrospective review was conducted to evaluate the appropriateness of empiric and definitive piperacillin use and to determine if less expensive, more appropriate antibiotics could have been used. The criteria were approved by the chief of infectious diseases and the drug utilization review committee at this institution. One hundred courses of piperacillin use in adult patients were reviewed. Therapy was categorized as appropriate in 78 of the 100 courses: 21 were appropriate empiric, 32 were appropriate empiric changed to definitive due to culture and sensitivity reports, and 25 were appropriate definitive. Reasons for this high percentage of appropriate use include: 1) 40% of the infections involved Pseudomonas aeruginosa; 2) 18% of the organisms that were sensitive to piperacillin were resistant to ticarcillin and mezlocillin; and 3) 64% of the courses of therapy involved critically ill patients with diagnoses such as neutropenia secondary to cancer chemotherapy, burns, sepsis, and hospital-acquired pneumonia. Although only 19.7% of the 11,845 grams of piperacillin used were categorized as inappropriate, the cost is relatively high (annualized to $19,648) and cost savings could be realized if piperacillin use were monitored more closely.