The mucosal inflammatory response to non-typhoidal Salmonella in the intestine is blunted by IL-10 during concurrent malaria parasite infection.

Coinfection can markedly alter the response to a pathogen, thereby changing its clinical presentation. For example, non-typhoidal Salmonella (NTS) serotypes are associated with gastroenteritis in immunocompetent individuals. In contrast, individuals with severe pediatric malaria can develop bacteremic infections with NTS, during which symptoms of gastroenteritis are commonly absent. Here we report that, in both a ligated ileal loop model and a mouse colitis model, malaria parasites caused a global suppression of gut inflammatory responses and blunted the neutrophil influx that is characteristic of NTS infection. Further, malaria parasite infection led to increased recovery of Salmonella enterica serotype Typhimurium from the draining mesenteric lymph node (MLN) of mice. In the mouse colitis model, blunted intestinal inflammation during NTS infection was independent of anemia but instead required parasite-induced synthesis of interleukin (IL)-10. Blocking of IL-10 in coinfected mice reduced dissemination of S. Typhimurium to the MLN, suggesting that induction of IL-10 contributes to development of disseminated infection. Thus IL-10 produced during the immune response to malaria in this model contributes to suppression of mucosal inflammatory responses to invasive NTS, which may contribute to differences in the clinical presentation of NTS infection in the setting of malaria.

Management of small solitary unilateral renal cell carcinomas: impact of central versus peripheral tumor location.

PURPOSE: Recent studies have suggested that nephron sparing surgery and radical nephrectomy provide equally effective therapy for patients with small (less than 4 cm.), solitary, unilateral renal cell carcinoma and a normal contralateral kidney. We evaluate whether central versus peripheral tumor location in the involved kidney is a significant factor affecting treatment outcome in these patients. MATERIALS AND METHODS: Patients with a single, small (less than 4 cm.), localized, unilateral, sporadic renal cell carcinoma were identified from our institutional registry. From 1972 to 1995, 145 patients fulfilling these criteria were treated with either nephron sparing surgery (86) or radical nephrectomy (59). Mean postoperative followup was 51.4 months. Tumor characteristics and outcome measures were analyzed in 35 patients with central versus 110 with peripheral renal cell carcinomas according to the type of treatment. RESULTS: We detected 27 central (77%) and 75 peripheral renal cell carcinomas (68%) incidentally. Nephron sparing surgery was used to treat 19 central (54%) and 67 peripheral (61%) carcinomas. Pathological tumor stage was T1 to 2 in 33 central (94%) and 91 peripheral (82%) cases. Grade 1 to 2 renal cell carcinoma was present in 28 central (80%) and 85 peripheral (77%) tumors. Postoperatively, when comparing patients with central versus peripheral renal cell carcinomas there was no difference in 5-year cancer specific survival (100 versus 97%), tumor recurrence (5.7 versus 4.5%) or renal function (mean serum creatinine 1.43 mg./dl. in both groups). These parameters were also equivalent in patients treated with nephron sparing surgery versus radical nephrectomy overall and within the central versus peripheral renal cell carcinoma subgroups. Nephron sparing surgery was technically more complicated in central renal cell carcinomas with a longer renal ischemia time (55 versus 34 minutes, p <0.05) and more frequent entry of the collecting system (74 versus 47%, p <0.05) compared to peripheral carcinomas. Two patients (2.3%, 1 central, 1 peripheral) had local tumor recurrence after nephron sparing surgery. CONCLUSIONS: There were no significant biological differences between centrally versus peripherally located small solitary unilateral renal cell carcinomas. Nephron sparing surgery is technically more demanding in patients with central tumors. However, treatment with nephron sparing surgery or radical nephrectomy is equally effective regardless of tumor location.

A correlative investigation of simulated occupant motion and accident report in a helicopter crash.

BACKGROUND: In the late 1980's, an Army Apache helicopter crashed during a training mission, resulting in fatal injuries to the rear seat pilot and survivable injuries to the front seat copilot. U.S. Army investigators assessed the aircraft damage and aircrew injuries, and examined the helmets, restraint systems, and crashworthy seats. HYPOTHESIS: Computer simulations that approximate an actual crash event can provide insightful output (human body motions and forces on the human body) that illuminates our understanding of the injury dynamics and the effect of safety systems designed to minimize injury. METHODS: Crash kinematics and vehicle accelerations were derived from the investigation and inferred from the aircraft damage, and input to a computer-based analytical simulation that calculated the dynamics and forces to which the crew were exposed. RESULTS: We treat the simulation like a looking glass into the event, revealing how and when safety devices could have responded during the crash, and the nature of injury-producing forces experienced by the occupants. Computer simulated whole-body and head-neck motion are graphically displayed, along with plots of joint forces, seat stroke, harness belt acceleration, and occupant accelerations. CONCLUSIONS: The calculated motions and forces indicated that injuries found in the accident were likely, hence the simulation may indeed be representative of the actual event.

Management of small unilateral renal cell carcinomas: radical versus nephron-sparing surgery.

OBJECTIVES: There is controversy concerning the management of small unilateral renal cell carcinomas. The present study was undertaken to evaluate the relative efficacy of radical nephrectomy versus nephron-sparing surgery in such patients. METHODS: Patients with a single, small (less than 4 cm), localized, unilateral, sporadic renal cell carcinoma (RCC) were identified from an institutional registry. From 1975 to 1992, 88 patients fulfilling these criteria were treated with either radical nephrectomy (n = 42) or nephron-sparing surgery (n = 46). The mean postoperative follow-up interval is 48 +/- 29 months. RESULTS: The radical and nephron-sparing surgical groups were well matched for patient age, sex, renal function, diabetes, hypertension, tumor size, tumor location, and tumor stage. All patients in both groups had low pathologic stage RCC. There was no difference between the two groups in terms of the mean hospital stay, the requirement for blood transfusions, or the occurrence of surgical complications. There was no difference in the mean preoperative and postoperative serum creatinine levels for patients in the nephron-sparing surgery group. However, the mean postoperative serum creatinine levels were significantly higher than the mean preoperative levels for patients in the radical nephrectomy group (P < 0.001). A single patient in each group developed recurrent RCC postoperatively. The cancer-specific 5-year survival rate for patients in the radical and nephron-sparing surgical groups is 97% and 100%, respectively. CONCLUSIONS: Radical nephrectomy and nephron-sparing surgery each provide safe and effective curative treatment for patients with a single, small, unilateral localized RCC. The long-term renal functional advantage of nephron-sparing surgery in this setting is not established.

Improved driving performance following perceptual training in persons with brain damage.

This study investigated (1) the modifiability of perceptual deficits by simple paper-and-pencil exercises, and (2) the effects of such exercises on driving performance. Eight subjects with acquired brain damage were given 8 to 10 hours of perceptual training. The training was preceded and followed by repeated evaluations of perceptual skills and in-traffic driving performance. Results indicated that (1) perceptual skills improved following such training, (2) the training was associated with improved driving performance, and (3) the degree of driving-performance improvement was directly related to the degree of improvement of perceptual skills.