The platelet interactivity phenotype of Streptococcus sanguis influences the course of experimental endocarditis.

A strain of Streptococcus sanguis that induced rabbit platelets to aggregate in vitro (Agg+ phenotype) was hypothesized to be a more virulent pathogen than an Agg- strain in experimental endocarditis in rabbits. A left ventricular catheter was implanted, and then an Agg+ or Agg- strain was inoculated intravenously. Vegetations formed on the aortic semilunar valves but were unaffected by the duration of implantation of the catheter. Vegetations enlarged by accumulating platelets and their mass increased directly with the duration of endocarditis. Inoculation of the Agg+ strain consistently caused endocarditis with significantly larger vegetations, a more severe clinical course (including febrile episodes, hematological changes, and signs of myocardial ischemia), more gross lesions in major organs, and greater mortality than inoculation with the Agg- strain, saline, or the Agg+ strain pretreated with monospecific rabbit immunoglobulin G or Fab fragments against its platelet aggregation-associated protein (PAAP; class II). In experimental endocarditis, PAAP expressed by Agg+ S. sanguis appeared to be an important virulence factor.     

Synovial fluid levels of fluconazole in a patient with Candida parapsilosis prosthetic joint infection who had an excellent clinical response

A 73-year-old woman presenting with persistent swelling of the right knee 30 months after total joint arthroplasty was found to have a Candida parapsilosis infection. Treatment with fluconazole resulted in full recovery.     

Calcium Concentration-dependent Mechanisms through which Ketamine Relaxes Canine Airway Smooth Muscle

Background: Ketamine is a potent bronchodilator that, in clinically used concentrations, relaxes airway smooth muscle in part by a direct effect. This study explored the role of calcium concentration (Ca2+) in this relaxation.

Methods: Canine trachea smooth muscle strips were loaded with the fluorescent probe fura-2 and mounted in a spectrophotometric system to measure force and intracellular calcium concentration ([Ca2+]i) simultaneously. Calcium influx was estimated using a manganese quenching technique. Cyclic nucleotides in the airway smooth muscle strips were measured by radioimmunoassay.

Results: In smooth muscle strips stimulated with submaximal (0.1 micro Meter) and maximal (10 micro Meter) concentrations of acetylcholine, ketamine caused a concentration-dependent decrease in force and [Ca2+]i. The sensitivity of the force response to ketamine significantly decreased as the intensity of muscarinic receptor stimulation increased; the median effective concentration for relaxation induced by ketamine was 59 micro Meter and 850 micro Meter for tissue contracted by 0.1 micro Meter or 10 micro Meter acetylcholine, respectively (P < 0.05). In contrast, the sensitivity of the [Ca2+] sub i response did not depend on the intensity of muscarinic receptor stimulation. Ketamine at 1 mM significantly inhibited calcium influx. Ketamine did not significantly increase cyclic nucleotide concentrations.     

Pharyngeal Patency in Response to Advancement of the Mandible in Obese Anesthetized Persons

Background: During anesthesia in humans, anterior displacement of the mandible is often helpful to relieve airway obstruction. However, it appears to be less useful in obese patients. The authors tested the possibility that obesity limits the effectiveness of the maneuver.

Methods: Total muscle paralysis was induced under general anesthesia in a group of obese persons (n = 9; body mass index, 32 +/- 3 kg sup -2) and in a group of nonobese persons (n = 9; body mas index, 21 +/- 2 kg sup -2). Nocturnal oximetry confirmed that none of them had sleep-disordered breathing. The cross-sectional area of the pharynx was measured endoscopically at different static airway pressures. A static pressure-area plot allowed assessment of the mechanical properties of the pharynx. The influence of mandibular advancement on airway patency was assessed by comparing the static pressure-area relation with and without the maneuver in obese and nonobese persons.

Results: Mandibular advancement increased the retroglossal area at a given pharyngeal pressure, and mandibular advancement increased the retropalatal area in nonobese but not in obese persons at a given pharyngeal pressure.     

Serum and Plasma Markers of Nutritional Status in Children Infected with the Human Immunodeficiency Virus

Objective To determine whether reduced serum or plasma protein and micronutrient levels are common in children infected with the human immunodeficiency virus (HIV) and whether these levels are different in children with growth retardation compared to those with normal growth.

Subjects Children were separated into three groups: (a) HIV-infected with growth retardation (HIV+Gr); (b) HIV-infected with normal growth (HIV+); (c) HIV-uninfected with normal growth (HIV-). All children were afebrile and free of acute infection at the time of study. During a 24-hour stay in the Pediatric Clinical Research Unit, blood was drawn for analysis of total protein, albumin, zinc, selenium, and vitamin A levels; growth measurements were obtained; and dietary intake was assessed by 24-hour weighed food intake and 24-hour dietary recall.

Statistical analysis Mean differences between groups were assessed by analysis of variance, and differences in the frequency of nutrient deficiency were determined by χ² analysis.

Results Thirty-eight children between 2 and 11 years of age were studied: 10 HIV+Gr, 18 HIV+, and 10 HIV-. No statistically significantly differences were noted in mean levels of albumin, prealbumin, zinc, and selenium. Mean serum level of vitamin A was significantly higher in the HIV+Gr group than in the other two groups. There were no significant differences between groups in the frequency of deficiency for any nutrient studied. Mean energy and nutrient intake was similar among groups.

Applications/conclusions Abnormal serum or plasma protein or micronutrient levels were uncommon in this cohort of HIV-infected children, even in children with growth retardation. Routine monitoring of the level of proteins and micronutrients studied is unnecessary in the absence of specific clinical indicators of deficiency. J Am Diet Assoc. 1997-97:1377-1381.     

Gastric Bypass for Morbid Obesity: a Standard Surgical Technique by Consensus

Background: The gastric bypass operation has evolved since 1966 when it was first introduced. The purpose of this study was to determine the present state of gastric bypass by consensus among the members of the American Society for Bariatric Surgery (ASBS). Method: A questionnaire was sent to all members of the ASBS. Forty-three percent responded reporting over 41,200 cases. Results: Results were analyzed by using χ² tests with a null hypothesis. Surgeons agreed on several technical aspects, preferring a vertical to a horizontal stapleline; estimating, rather than measuring, the pouch volume at an average of 22 cc. Few surgeons divide the short gastric vessels, and only 25% of surgeons polled use a restrictive ring or band proximal to the gastroenterostomy. Most surgeons calibrate the gastroenterostomy, reporting a preferred average diameter of 12.3 cm. There was no consensus regarding forming the gastroenterostomy, 58% preferring hand-sewn and 42% stapled anastomoses. There was no consensus regarding dividing the gastric pouch from the bypassed stomach: Conclusion: The preferred gastric bypass is vertical, with the pouch estimated at 20-25 cc, and the gastroenterostomy calibrated at 12 mm diameter. The short gastric vessels need not be divided, and restrictive bands or rings are not preferred. This technique of gastric bypass should be used as the control procedure when modifications are tested in future trials. Randomized prospective studies are suggested to probe the benefits of division of the stomach pouch from the bypassed stomach.     

Phase II trial of gallium nitrate,amonafide and teniposide in metastatic non-small cell lung cancer

Summary Fifty-five patients with metastatic non-small cell lung cancer (NSCLC) were entered into this phase II randomized study for evaluating three new agents: gallium nitrate, amonafide and teniposide. The patients had to have ECOG performance status 0 or 1, no prior chemotherapy, and adequate hematological, hepatic and renal functions. Forty-seven patients were eligible and evaluable. Fourteen were randomized to receive gallium nitrate, 18 to amonafide and 15 to teniposide. Seventy-four percent of eligible patients were male. The majority of patients (89%) had an ECOG performance status 1. ECOG grade 4 toxicity occurred twice in patients on gallium nitrate, seven times on amonafide and 18 times on teniposide. The cause of death was attributed to amonafide in one patient (from sepsis) and to teniposide in two patients (due to infection and leukopenia). There was no objective response in all the patients entered. The overall survival times ranged from 2 weeks to 156 weeks with a median of 23 weeks. There were no survival differences among the three treatment arms. We conclude that gallium nitrate, amonafide and teniposide are inactive in metastatic NSCLC and do not warrant any further testing in this disease.The contents of this study is solely the responsibility of the authors and does not necessarily represent the official views of the National Cancer Institute.     

A COMPARISON OF KETOPROFEN SR AND SULINDAC IN THE ELDERLY WITH RHEUMATOID ARTHRITIS

The elderly (age >65 years) are more vulnerable to side-effects induced by non-steroidal anti-inflammatory drugs (NSAIDs). We therefore performed a double-blind comparative study of ketoprofen SR and sulindac in patients with active rheumatoid arthritis, 65 years of age or older. Sulindac was chosen because of its possible renal sparing effects, and ketoprofen SR because of its short half life and sustained release delivery system. Eighty patients were entered. More patients withdrew from the study due to side-effects in the sulindac group; both treatment groups had a high incidence of side-effects during this study and during previous exposure to other NSAIDs, demonstrating that the elderly are susceptible to side-effects from NSAIDs.