The utility of traditional prehospital interventions in maintaining thermostasis

Objective. Hypothermia can have a negative effect on the metabolic and hemostatic functions of patients with traumatic injuries. Multiple methods of rewarming are currently used in the prehospital arena, but little objective evidence for their effectiveness in this setting exists. The purpose of this study was to assess the relative effectiveness of traditional prehospital measures in maintaining thermostasis in trauma patients. Methods. Participating helicopter and ground ambulance ALS units were prospectively randomized to provide either routine care only (passive or no warming) or routine care (passive warming) in conjunction with active warming (either reflective blankets, hot pack rewarming, or warmed IV fluids). A total of 174 trauma code patients, aged >14 years, who met inclusion criteria were prospectively enrolled by prehospital providers. Patients who received a non-assigned intervention or who had incomplete temperature data were dropped from the analysis. A total of 134 patients were included in the final analysis. Results. Patients who received hot pack rewarming showed a mean increase in body temperature during transport (+1.36°F/0.74°C), while all other groups (no intervention, passive rewarming, reflective blankets, warmed IV fluids, warmed IV fluid plus reflective blanket) showed a mean decrease in temperature during transport [-0.34 to -0.61°F (-0.2 to -0.4°C); p < 0.01]. In addition, the hot pack group was consistent, with every patient who received hot pack warming showing an increase in body temperature during transport, while in all other groups there were patients who had both increases and decreases in temperature. The intervention groups did not differ significantly on exposure to precipitation, transport unit temperature, total prehospital time, initial vital signs, amount of fluid administered, Injury Severity Score, or Glasgow Coma Score. Conclusions. Most traditional methods of maintaining trauma patient temperature during prehospital transport appear to be inadequate. Aggressive use of hot packs, a simple, inexpensive intervention to maintain thermostasis, deserves further study as a potential basic intervention for trauma patients.     

Prevalences, genotypes, and risk factors for HIV transmission in South America

HIV cross-sectional studies were conducted among high-risk populations in 9 countries of South America. Enzyme-linked immunosorbent assay screening and Western blot confirmatory testing were performed, and env heteroduplex mobility assay genotyping and DNA sequencing were performed on a subset of HIV-positive subjects. HIV prevalences were highest among men who have sex with men (MSM; 2.0%-27.8%) and were found to be associated with multiple partners, noninjection drug use (non-IDU), and sexually transmitted infections (STIs). By comparison, much lower prevalences were noted among female commercial sex workers (FCSWs; 0%-6.3%) and were associated mainly with a prior IDU and STI history. Env subtype B predominated among MSM throughout the region (more than 90% of strains), whereas env subtype F predominated among FCSWs in Argentina and male commercial sex workers in Uruguay (more than 50% of strains). A renewed effort in controlling STIs, especially among MSM groups, could significantly lessen the impact of the HIV epidemic in South America.     

Comparison of MICs of ceftiofur and other antimicrobial agents against bacterial pathogens of swine from the United States, Canada, and Denmark.

The MICs of ceftiofur and other antimicrobial agents, tested for comparison, for 515 bacterial isolates of pigs from the United States, Canada, and Denmark with various diseases were compared. The organisms tested included Actinobacillus pleuropneumoniae, Escherichia coli, Pasteurella multocida, Salmonella choleraesuis, Salmonella typhimurium, Streptococcus suis, Streptococcus dysgalactiae subsp. equisimilis, Streptococcus equi subsp. equi, and Streptococcus equi subsp. zooepidemicus. In addition to ceftiofur, the following antimicrobial agents or combinations were tested: enrofloxacin, ampicillin, sulfamethazine, trimethoprim-sulfadiazine (1:19), erythromycin, lincomycin, spectinomycin, lincomycin-spectinomycin (1:8), tilmicosin, and tetracycline. Tilmicosin was only tested against the U.S. isolates. Overall, ceftiofur and enrofloxacin were the most active antimicrobial agents tested against all isolates, with MICs inhibiting 90% of isolates tested (MIC90s) of < or = 2.0 and < or = 1.0 microgram/ml, respectively. Erythromycin, sulfamethazine, spectinomycin, and lincomycin demonstrated limited activity against all of the organisms tested, with MIC90s of > or = 8.0, > or = 256.0, > or = 32.0, and > or = 16.0 micrograms/ml, respectively. Trimethoprim-sulfadiazine was active against isolates of A. pleuropneumoniae, S. choleraesuis, S. typhimurium, P. multocida, S. equi, and S. suis (MIC90s, < or = 0.5 microgram/ml) but was less active against the E. coli strains tested (MIC90, > 16.0 micrograms/ml). Ampicillin was active against the P. multocida, S. suis, and S. equi isolates tested (MIC90s, 0.5, 0.06, and 0.06 micrograms/ml, respectively) and was moderately active against S. typhimurium (MIC90s, 2.0 micrograms/ml). However, this antimicrobial agent was much less active when it was tested against A. pleuropneumoniae, S. cholerae-suis, and E. coli (MIC90s, 16.0, > 32.0, and 32.0 micrograms/ml, respectively). Against the U.S. isolates of A. pleuropneumoniae and P. multocida, tilmicosin was moderately active (MIC90s, 4.0 and 8.0 micrograms/ml, respectively). However, this compound was not active against the remaining U.S. isolates (MIC90s, > 64.0 micrograms/ml). Differences in the MICs from one country to another were not detected with enrofloxacin, ceftiofur, or lincomycin for the strains tested, but variations in the MICs of the remaining antimicrobial agents were observed.     

The Association Between Toddlerhood Self-Control and Later Externalizing Problems

Lower self-control is a significant correlate or predictor of a wide range of adult outcomes, and this association may be due to more general tendencies toward childhood externalizing problems. The present study examined the association between toddlerhood self-control expressed within a “don’t” compliance task (at 14–36 months) and later externalizing problems (parent-reported externalizing problems from age 4 to 12 years, teacher-reported externalizing problems from age 7 to 12 years, and self-reported conduct disorder symptoms at age 17 years) in a longitudinal, genetically informative study. The slope of self-control, but not its intercept, predicted later teacher-reported, but not parent- or self-reported, externalizing problems. That is, increase in self-control during toddlerhood was associated with lower levels of later teacher-reported externalizing problems. The slope of self-control was no longer a significant predictor of teacher-reported externalizing problems after controlling for observed disregard for others, a robust predictor of externalizing problems. Thus, the hypothesis that self-control is the primary predictor of externalizing problems was not supported. Results from genetic analyses suggested that the covariance between the slope of self-control and teacher-reported externalizing problems is due to both genetic and shared environmental influences.     

Gonadal steroids influence neurophysin II distribution in the forebrain of normal and mutant mice

The distribution of arginine vasopressin-associated neurophysin (neurophysin II) immunoreactivity was investigated in normal and mutant house mice during development and after various gonadal steroid manipulations. During postnatal development of normal mice dense networks of neurophysin II immunoreactivity in the lateral septal nucleus and lateral habenular nucleus appeared earlier in male than in female mice, with an adult pattern of immunoreactivity being attained by 8 weeks and 12 weeks of age, respectively. The neurophysin II immunoreactivity in the male was denser than that in female mice. After gonadectomy of adult normal mice there was a gradual loss of neurophysin II immunoreactivity in the lateral septum and lateral habenula over a period of 15 weeks. In hypogonadal mice, a mutant in which gonadal development is arrested postnatally due to a deficiency in hypothalamic gonadotrophin releasing hormone, no immunoreactive neurophysin II could be detected in the lateral septum or lateral habenula. A pattern of neurophysin II immunoreactivity similar to that in normal control mice was observed in hypogonadal mice which had been implanted for 4 weeks with silicone elastomer capsules containing testosterone or oestradiol-17 beta, but not 5 alpha-dihydrotestosterone or progesterone. Stimulation of gonadal development and endogenous steroid production in hypogonadal mice by third ventricular grafts of preoptic area tissue from normal neonatal animals also produced a normal pattern of neurophysin II immunoreactivity in the lateral septum and lateral habenula. In the androgen-insensitive testicular feminized mouse immunoreactive neurophysin II was undetectable in the lateral septum and lateral habenula. Treatment of testicular feminized mice with oestradiol-17 beta, but not progesterone, produced a normal pattern of neurophysin II immunoreactivity. The main immunohistological findings were confirmed by radioimmunoassay of tissue extracts which showed that the concentration of arginine vasopressin in lateral septum was far greater in normal males than females and was undetectable in hypogonadal mice; no oxytocin could be detected in the septum of normal or hypogonadal mice. These results show that the expression of neurophysin II immunoreactivity in the lateral septum and lateral habenula of the mouse brain is dependent on the presence of aromatizeable androgens or oestrogens.     

Assessment of new radioimmunoassay kit for determining urinary albumin at low concentrations: comparison with radial immunodiffusion.

The assay characteristics of a new radioimmunoassay kit for determining urinary albumin at low concentrations were studied. The sensitivity for urinary albumin was 2 mg/l, the analytical range 2 to 40 mg/l, and interassay coefficient of variation less than 12%. In a method comparison study entailing diabetic urine samples covering an albumin concentration of 2 to 150 mg/l the kit compared adequately with radial immunodiffusion (mean difference between methods = 2 mg/l; residual standard deviation = 4.6 mg/l), absolute variation between methods increasing with the concentration. The kit required much less skill than radial immunodiffusion but its capital and running cost were higher.     

51-year-old woman with double vision

A 51-year-old woman presented with a 2-month history of double vision and numbness around her left ear. She subsequently became unsteady on her feet and developed further cranial nerve abnormalities, before complaining of headache, nausea and vomiting. Imaging revealed features suggestive of two intracranial lesions; one non-contrast-enhancing high-signal area in the cerebellum with associated calcification, and a second contrast-enhancing low-signal area in association with the fourth ventricle, and at surgery there were two apparent components to the tumor. The histopathological features were those of a low-grade, focally calcified tumor comprising atypical ganglion and glial cells with interspersed Rosenthal fibres. Mitotic figures were not seen, and there was no necrosis. An infiltrate of small reactive lymphocytes was interspersed among the neoplastic cells. Immunohistochemistry revealed expression of synaptophysin by many of the dysplastic ganglion cells, with some co-expressing neurofilament protein and occasionally glial fibrillary acidic protein (GFAP). Several of the dysplastic ganglion cells also expressed CD34. The glial cell population was highlighted by GFAP. Ki-67 (MIB-1) activity was not noted among the neoplastic populations--the few positive nuclei in these areas were those of interspersed reactive CD3-positive T lymphocytes. In addition, at the edge of one of the biopsies was a dense infiltrate of mitotically-active large atypical CD 20-positive B lymphocytes, among which the Ki-67 (MIB-1) labeling index reached 80%. The final diagnosis was diffuse large B cell lymphoma arising within a ganglioglioma of the cerebellum, and this is believed to be the first reported case.     

Candesartan Normalizes Changes in Retinal Blood Flow and p22phox in the Diabetic Rat Retina

Angiotensin II has been implicated in the progression of diabetic retinopathy, which is characterized by altered microvasculature, oxidative stress, and neuronal dysfunction. The signaling induced by angiotensin II can occur not only via receptor-mediated calcium release that causes vascular constriction, but also through a pathway whereby angiotensin II activates NADPH oxidase to elicit the formation of reactive oxygen species (ROS). In the current study, we administered the angiotensin II receptor antagonist candesartan (or vehicle, in untreated animals) in a rat model of type 1 diabetes in which hyperglycemia was induced by injection of streptozotocin (STZ). Eight weeks after the STZ injection, untreated diabetic rats were found to have a significant increase in tissue levels of angiotensin converting enzyme (ACE; p < 0.05) compared to non-diabetic controls, a 33% decrease in retinal blood flow rate (p < 0.001), and a dramatic increase in p22phox (a subunit of the NADPH oxidase). The decrease in retinal blood flow, and the increases in retinal ACE and p22phox in the diabetic rats, were all significantly attenuated (p < 0.05) by the administration of candesartan in drinking water within one week. Neither STZ nor candesartan induced any changes in tissue levels of superoxide dismutase (SOD-1), 4-hydroxynonenal (4-HNE), or nitrotyrosine. We conclude that one additional benefit of candesartan (and other angiotensin II antagonists) may be to normalize retinal blood flow, which may have clinical benefits in diabetic retinopathy.     

Finger opening in an overarm throw is not triggered by proprioceptive feedback from elbow extension or wrist flexion

 Accuracy in an overarm throw requires great precision in the timing of finger opening. We tested the hypothesis that finger opening in an overarm throw is triggered by proprioceptive feedback from elbow extension or wrist flexion. The hypothesis was tested in two ways: first, by unexpectedly perturbing elbow extension or slowing wrist flexion and determining whether changes occurred in finger opening, and second, by measuring the latency from the start of these joint rotations to the start of finger opening. Subjects threw balls fast and accurately from a sitting or standing position while joint rotations were recorded with the search-coil technique. Elbow extension was unexpectedly blocked near the start of forward motion of the hand by a rope attached to the wrist that passed through a catch mechanism located behind the subject. In spite of a slowing or complete block of elbow extension, and in some cases a replacement of elbow extension by elbow flexion, finger opening always occurred and at the same latency as for normal throws. Wrist flexion was slowed in seven of eight subjects when subjects changed from throwing with a light ball (14 g, 70 mm diam.) to a heavy ball (210 g, 65 mm diam.). For the first throw with the heavy ball, this slowing was neither fully anticipated by the subject nor compensated for by the changed proprioceptive feedback associated with the slowing. Consequently, the timing of finger opening was unchanged and (to the surprise of the thrower) the ball went high. Furthermore, in unperturbed throws with tennis balls, the latency from onset of wrist flexion or elbow extension to onset of finger opening was too short for either to have triggered finger opening (across subjects means were 4 ms for wrist flexion and 21 ms for elbow extension). In additional analysis, no relation was found between the time of onset of earlier occurring rotations at the shoulder and the time of onset of finger opening. We concluded that, although a role for all proprioceptive feedback in triggering finger opening cannot be disproved by these experiments, it can be ruled out for feedback arising from elbow extension and wrist flexion, and it seems unlikely for feedback arising from events occurring very early in the throw. The more likely possibility is that finger opening in an overarm throw is triggered by a central command based on an internal model of hand trajectory. Received: 6 July 1998 / Accepted: 16 October 1998     

Serum lipids, lipoproteins and apolipoproteins in pregnant non-diabetic patients.

AIMS--To investigate the effect of pregnancy on serum concentrations of lipids, lipoproteins, and apolipoproteins. METHODS--Fasting serum concentrations of total cholesterol, triglyceride, low density lipoprotein cholesterol (LDL), high density lipoprotein cholesterol (HDL), apolipoproteins AI, AII, and B, and lipoprotein (a) were measured in 178 women with normal glucose tolerance in the second and third trimesters of pregnancy and in a control group of 58 non-pregnant women of similar age. Data were analysed using the unpaired t test and by one-way analysis of variance. RESULTS--The pregnant women had significantly higher concentrations of total cholesterol, triglyceride, LDL cholesterol, HDL cholesterol, and apolipoproteins AI and B (p < 0.001) and apolipoprotein AII (p = 0.003) than the control women. The ratio of apolipoprotein B:apolipoprotein AI was significantly higher in the pregnant women than in the controls (p < 0.001), but the total cholesterol:HDL cholesterol ratio was not significantly different. No significant difference was found in the concentration of lipoprotein (a). CONCLUSIONS--Hyperlipidaemia is common in the second half of pregnancy. This may be a purely physiological response to pregnancy or it may be indicative of pathology in some women. These results warrant a follow up study to investigate whether the hyperlipidaemic response to pregnancy is variable and if so, whether it can predict future hyperlipidaemia in a manner analogous to that of impaired glucose tolerance during pregnancy, predicting non-insulin dependent diabetes in later life.