Occupational neurology and the hand. Differential diagnosis

Occupationally related dysfunction of the peripheral nervous system is a common problem. The signs and symptoms of neurologic problems of the upper extremity and neck that can alter hand function and sensation are described in detail.     

Trends in infant bed sharing in the United States, 1993-2000: the National Infant Sleep Position study

BACKGROUND: Bed sharing with parents has been described as both beneficial to infant well-being and as a potentially lethal situation. OBJECTIVE: To examine trends in bed sharing between infants and caregivers, and the factors that influence this behavior. DESIGN: Annual nationally representative telephone surveys conducted between 1993 and 2000. SETTING: The 48 contiguous United States. PARTICIPANTS: Nighttime caregivers of infants born within 7 months prior to interview between 1993 and 2000. Approximately 1000 interviews were conducted each year for a total sample of 8453 nighttime caregivers. MAIN OUTCOME MEASURES: Where and with whom the infant usually slept at night in the preceding 2 weeks. RESULTS: Forty-five percent of infants spent at least some time at night on an adult bed in the last 2 weeks. Between 1993 and 2000, the proportion of infants usually sharing an adult bed at night increased from 5.5% to 12.8%. More than 90% of infants who "usually" slept on an adult bed shared it with their parents. In a multivariate analysis, factors associated with increased probability of routine bed sharing included: maternal age less than 18 years (odds ratio [OR] = 2.26; 95% confidence interval [CI], 1.22-4.21), maternal race or ethnicity reported as black (OR = 4.04; 95% CI, 3.04-5.36) or as Asian or "other" (OR = 2.72; 95% CI, 1.74-4.22), household income less than $20,000 (OR = 1.49; 95% CI, 1.15 = 1.92), living in the Southern states compared with living in the Midwest (OR, 1.59; 95% CI = 1.23, 2.06), and infant age less than 8 weeks (OR = 1.60; 95% CI, 1.10-2.33). Living in the Mid-Atlantic compared with the Midwest (OR = 0.63; 95% CI, 0.44-0.90), and being born with low birthweight and preterm (OR = 0.32; 95% CI, 0.14-0.74) were associated with decreased probability of routine bed sharing. CONCLUSIONS: Bed sharing as a routine practice is growing in the United States. Given that this practice seems to be widespread and strongly influenced by cultural factors, more studies of the consequences of bed sharing are needed to inform health care providers and parents on the risks and benefits.     

Randomized trial of tacrolimus + mycophenolate mofetil or azathioprine versus cyclosporine + mycophenolate mofetil after cadaveric kidney transplantation: results at three years

METHODS: Two hundred twenty-three recipients of first cadaveric kidney allografts were randomized to receive tacrolimus (TAC) + mycophenolate mofetil (MMF), TAC + azathioprine (AZA), or cyclosporine (Neoral; CsA) + MMF. All regimens contained corticosteroids, and antibody induction was used only in patients who experienced delayed graft function (DGF). Patients were followed-up for 3 years. RESULTS: The results at 3 years corroborate and extend the findings of the 2-year results. Patients with DGF treated with TAC+MMF experienced an increase in 3-year allograft survival compared with patients receiving CsA+MMF (84.1% vs. 49.9%, P=0.02). Patients randomized to either treatment arm containing TAC exhibited numerically superior kidney function when compared with CsA. During the 3 years, new-onset insulin dependence occurred in 6, 3, and 11 patients in the TAC+MMF, CsA+MMF, and TAC+AZA treatment arms, respectively. Furthermore, patients randomized to TAC+MMF received significantly lower doses of MMF as compared with those who received CsA+MMF. CONCLUSION: All three immunosuppressive regimens provided excellent safety and efficacy. However, the best results overall were achieved with TAC+MMF. The combination may provide particular benefit to kidney allograft recipients with DGF. In patients who experienced DGF, graft survival was better at 3 years in those patients receiving TAC in combination with either MMF or AZA as compared with the patients receiving CsA with MMF.     

Anemia and blood transfusion in trauma patients admitted to the intensive care unit

BACKGROUND: Anemia is a common occurrence in the intensive care unit (ICU). Although resuscitation, including the use of blood, is a mainstay of early treatment of trauma victims, the safety and efficacy of red blood cell (RBC) transfusion has come under scrutiny recently. The issue of blood use in critically injured patients requires evaluation. METHODS: This was a post hoc analysis of a subset of trauma patients (> or =18 years in age) from a prospective, multicenter, observational, cohort study in the United States. Patients were enrolled within 48 hours after ICU admission and followed for up to 30 days, or until hospital discharge or death. RESULTS: Five hundred seventy-six patients from 111 ICUs in 100 hospitals were enrolled between August 2000 and April 2001. At baseline, mean age was 44.1 +/- 20.2 years, 73.6% were men, and mean APACHE II score was 16.9 +/- 8.2. Mean baseline hemoglobin was 11.1 +/- 2.4 g/dL and patients remained anemic throughout the study either with or without transfusion; 55.4% of patients were transfused (mean, 5.8 +/- 5.5 units) during the ICU stay and 43.8% of patients had an ICU length of stay > or = 7 days. Mean pretransfusion hemoglobin was 8.9 +/- 1.8 g/dL. Mean age of RBCs transfused was 20.1 +/- 11.4 days. As compared with the full study population, patients in the trauma subset were more likely to be transfused and received an average of 1 additional unit of blood. CONCLUSION: Anemia is common in critically injured trauma patients and persists throughout the duration of critical illness. These patients receive a large number of RBC transfusions during their ICU course with aged blood.     

Effects of baclofen on operant performance for food pellets and vegetable shortening after a history of binge-type behavior in non-food deprived rats

Operant performance of non-food deprived rats (n=8) was assessed under progressive ratio (PR) and concurrent PR-fixed ratio schedules of food pellet and/or vegetable shortening reinforcement. Post operant baselines, rats were matched and divided into 2 groups based upon the schedule of shortening availability: High restriction binge group (H, 1-hr home cage shortening access each week on Monday, Wednesday, and Friday) and Low restriction (L, 1-hr shortening access daily). Chow and water were continuously available; only access to the shortening was restricted. After 8 weeks, operant performance was reassessed. Lever pressing for shortening increased in the H rats for all schedules, but was either unaffected or decreased in the L rats. Pellet responding under the concurrent schedules increased for both groups. The effects of four dosages of (R)-baclofen (0.3-1.8 mg/kg, i.p.) on operant performance were also assessed. For both groups, 1.0 mg/kg baclofen significantly reduced shortening responding relative to saline for all schedules except one, but had no or minimal effect on pellet responding. This suggests a specific effect of baclofen on responding maintained by fat. These results indicate that intermittent episodes of bingeing on fat can increase the reinforcing efficacy of fat and that GABAB receptor activation can attenuate this effect.     

Unilateral destruction of the dorsocentral striatum in rats produces neglect but not extinction to bilateral simultaneous stimulation

A number of previous studies have indicated that lesions of the medial agranular cortex (AGm) in rats induce multimodal neglect and extinction to bilateral simultaneous stimulation (extinction), the two major symptoms of the neglect syndrome in humans. A recent study demonstrated that lesions of dorsocentral striatum (DCS), the site of AGm projections to the striatum, produce multimodal neglect qualitatively similar to that found with AGm lesions. In the present study, the behavioral effects of unilateral DCS lesions were examined in more detail for the major manifestations of neglect: hemineglect, extinction, and allesthesia/allokinesia. Subjects were tested for extinction to bilateral simultaneous stimulation of the forepaws three times a week for 3 weeks. Neglect testing occurred twice weekly and the subjects were tested for the presence of neglect by rating the magnitude of orientation to visual, tactile, and auditory stimulation. The results indicated that DCS operates, while demonstrating severe neglect, failed to demonstrate extinction or allesthesia/allokinesia. These findings suggest that the neural mechanisms that underlie neglect and extinction are dissociable in this system. A better understanding of the neural mechanisms that underlie extinction is particularly important because humans that have recovered from neglect often continue to demonstrate the debilitating symptoms of extinction.