Hip impact velocities and body configurations for voluntary falls from standing height

OBJECTIVE: To determine prevalence of various pheno- and genotypes of Serpulina sp in young pigs in relation to diarrhea and feed medication in Swedish pig-rearing herds. DESIGN: Isolation of spirochetes. Phenotypical and genotypical classification. SAMPLE POPULATION: Young pigs (n = 358) in 19 pigrearing herds. PROCEDURE: Serpulina isolates were classified according to a biochemical scheme based on hemolysis, indole production, hippurate hydrolysis, and alpha-galactosidase, alpha-glucosidase, and beta-glucosidase activities. The 16S rRNA sequences for 10 of the field strains and 2 type strains of Serpulina spp were aligned and compared. Minimum inhibitory concentrations of olaquindox for 9 of the strains were determined. RESULTS: Weakly beta-hemolytic intestinal spirochetes (WBHIS) were isolated from 17 of the herds and 65% of the samples. More than 1 phenotype of WBHIS was found in 12 of the 19 herds. S hyodysenteriae was not isolated in any of the herds. Hippurate-positive WBHIS were isolated in 6 of 7 herds affected by diarrhea, but in only 1 of 8 herds without diarrhea. Hippurate-positive strains were closely related to the pathogenic strain P43 if judged from sequence comparisons. Strains with the same biochemical profile isolated within a herd had identical sequences, but when isolated from different herds, sequence differences were observed. The prevalence of WBHIS was reduced in herds medicated with olaquindox. Investigated field strains had minimum inhibitory concentration values < or = 1 microgram/ml for olaquindox. CONCLUSION: The presence of WBHIS, with the ability to hydrolyze hippurate, was related to diarrhea in pig herds. CLINICAL RELEVANCE: Potentially pathogenic WBHIS can be distinguished from nonpathogenic strains by the hippurate hydrolysis test.     

Modeling of acute spinal cord injury in the rat: neuroprotection and enhanced recovery with methylprednisolone, U-74006F and YM-14673

We used a new injury device that produces consistent spinal cord contusion injuries (T8) in rats to compare the behavioral and histologic effects of methylprednisolone sodium succinate (MPSS) administration, the clinical standard of therapy after acute spinal cord injury (ASCI), with the 21-aminosteroid, U-74006F (U74), and the TRH analogue, YM-14673 (YM), at different trauma doses. Three sequential experiments were conducted: Experiment 1. U74 (3.0/1.5/1.5 mg/kg; 10/5/5 mg/kg; 30/15/15 mg/kg), MPSS (30/15/15 mg/kg), or vehicle were administered intravenously (i.v.) at 5 min, 2 and 6 h after the injury (n = 8/group). U74 (10/5/5 mg/kg) and MPSS animals scored better than controls (Days 8-43) in open field walking (OFW); no other differences were seen between groups. Experiment 2. Dose-response evaluation of MPSS determined more effective doses. Groups (n = 16) receiving 30/30/30/30 mg/kg and 60/60/60/60 mg/kg i.v. at 5 min and 2, 4, and 6 h after the injury had better OFW scores than controls (Days 8-29; Day 29). Both groups performed better than controls (Days 8-29) on inclined plane (IP); 30 mg/kg animals scored higher on Day 29. Percentage tissue spared (%TS) at the lesion center was greater for 60 mg/kg animals (23.4%) than controls (17.3%). Experiment 3. Compounds were administered as in experiment 2 (n = 15/group); MPSS (60/30/30/30 mg/kg) and YM (1/1/1/1 mg/kg and 1 mg/kg/day ip) were most effective. YM and MPSS combination produced no additive effects. YM animals scored better than MPSS and control animals in OFW (Days 8-29) and better than controls on IP (Days 8-29; Day 29) and grid walking (Day 29). MPSS animals scored better than controls on IP (Days 8-29). YM and MPSS groups had greater %TS than controls. This series of experiments demonstrates the utility of this injury model and simple behavioral measures for preclinical assessment of pharmacologic agents. Under these experimental conditions, U74 demonstrated equivalent efficacy to MPSS, and YM demonstrated greater efficacy than MPSS in the treatment of ASCI.     

Polymorphism of bacteriophage T7

For viruses made of nucleic acid and protein, the structure of the protein outer shell has, in the past, been found to be uniquely determined by the viral genome. However, here, non-denaturing agarose gel electrophoresis of bacteriophage T7 reveals two states of the mature T7 capsid; the conditions of growth are found to alter the population by T7 of these two electrophoretically defined states. Both states have been previously observed for a genetically altered T7 and they are observed here for wild-type T7. The average electrical surface charge density of a bacteriophage particle (delta) determines its state; the delta of particles in both states is negative. For a given condition of growth, the population of these two states is influenced by the extent to which the major T7 outer shell protein, p10A, is accompanied by its minor readthrough variant, p10B. Comparison of the two electrophoretic states reveals the following. (1) No difference in radius is present in the outer shell (+/-2%). (2) As the pH of electrophoresis is either increased or decreased from neutrality, the state becomes more highly populated for which delta is greater in magnitude (state 1). By changing the pH, some T7 particles are made to change state. (3) Particles in state 1 adsorb less quickly to host cells than do the particles in the alternative state (state 2). This latter observation suggests the hypothesis that state 1 evolved to reduce the probability of re-initiating an infection when conditions are not favorable for growth. This hypothesis is supported by the observation that, as conditions of growth become apparently more unfavorable, progeny increasingly populate state 1.     

Modulation of embryonic glutathione peroxidase activity and phenytoin teratogenicity by dietary deprivation of selenium in CD-1 mice

Selenium (Se)-dependent and -independent glutathione (GSH) peroxidases detoxify H2O2 and lipid hydroperoxides, which may mediate the teratogenicity of phenytoin and related xenobiotics. To test this hypothesis, CD-1 mice were placed on Se-deficient diets for 15, 25 or 40 days and bred so that the day of analysis corresponded to gestational day 11. In Se-replete control animals, embryonic peroxidase activities were only 5% of activities in maternal liver (P < .05). After 15 days of Se deprivation, maternal activities for H2O2 (reflecting Se-dependent peroxidase) and cumene hydroperoxide (CmOOH) (reflecting both Se-dependent and -independent peroxidases) were reduced to 20% (P < .05) and 35% of controls, respectively. At this time, the incidence of fetal cleft palates initiated by phenytoin (55 mg/kg intraperitoneally on gestational days 11, 12 and 13) was doubled, from 12% to 25% (P < .05). Selenite rescue (Na2SeO3, 350 micrograms/kg intraperitoneally on day 9) restored maternal and embryonic peroxidase activities and completely inhibited phenytoin-initiated postpartum lethality and fetal resorptions in animals that had been Se depleted for 15 days. After 40 days of Se deprivation, maternal and embryonic peroxidase/H2O2 activities were reduced to < 1% and 27% of Se-replete controls, respectively. In contrast, maternal peroxidase/CmOOH activity was increased to 70% of controls, reflecting induction of Se-independent peroxidase, compared with that with 15 days' depletion. Phenytoin-initiated cleft palates with 40 days' depletion appeared to be reduced (16%) compared with Se-replete controls (24%) (P < .07). In 40-day Se-depleted animals given selenite rescue, the 10% incidence of cleft palates was significantly lower than that in the 40-day Se-replete group (24%) but not the Se-depleted group (16%). This is the first demonstration of reduced Se-dependent GSH peroxidase activities in embryonic tissues with dietary Se-deprivation. The results implicate reactive oxygen species and lipid hydroperoxides in the mechanism of phenytoin teratogenicity and suggest that GSH peroxidases are important embryoprotective enzymes.     

"Cadism": Odd man out.

Comments that L. B. Silverstein's (see record 1992-05293-001) article on child care and maternal employment contributes unfounded and damaging misbeliefs regarding fathers. The dad-as-cad myth suggests intentional malevolence or at least blatant failure by fathers to care for others, and suggests that their failure to share equally in child care and household management is the primary cause of marital conflict. W. B. Johnson and D. Hayes propose a research agenda for fathering that originates in a coherent model of male development in the context of ever-changing environmental demands. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Co-morbidities and survival of men with localized prostate cancer treated with surgery or radiation therapy

PURPOSE: We determined the impact of preexisting co-morbidities on survival of men with clinical stages T1b and T2NXM0 prostate cancer treated with surgery or radiation therapy. MATERIALS AND METHODS: A weighted co-morbidity score was determined for 276 consecutive men treated with surgery (138) or radiation therapy (138) at a Veterans Affairs medical center and was correlated with actuarial freedom from death due to co-morbid disease. RESULTS: After a median potential followup of 7.0 years 91 patients (33%) died of co-morbid disease and 20 (7%) died of cancer related causes. There were highly significant correlations between actuarial survival and weighted co-morbidity (p < 0.000001), and the 10-year actuarial survivals in men with no or severe co-morbidities were 66 and 9%, respectively. Associations between patient age and co-morbidity score were highly significant (p < 0.0001). The age adjusted risk of co-morbid death was 5.7 times greater in men with severe compared to no co-morbidities. There were also significant correlations between actuarial survival and weighted co-morbidity among patients treated with surgery (p = 0.02) and radiation therapy (p = 0.0002). Patient age and severity of co-morbidities were significantly greater among men treated with radiation therapy compared to surgery, and age adjusted risk of co-morbid death among men with a co-morbidity score of 1 was 3.8 times greater among men treated with radiation therapy (p = 0.025). CONCLUSIONS: Cancer related deaths are unusual within 5 to 10 years after surgery or radiation therapy in men with stages T1b and 2 prostate cancer. The risk of death during this interval is directly related to the severity of co-morbid conditions, which should be factored in an individual when assessing the advisability of therapeutic intervention. Since patient co-morbidities impact all cause survival, quantitative assessment of co-morbidities using validated instruments offers a method to control partially for the variabilities of health status among men receiving different treatments for localized prostate cancer.     

Nonlinearity of p-i-n photodetectors

At higher operating frequencies, the field dependence of the carrier velocity in p-i-n photodetectors generates harmonics and intermodulation products that can degrade the dynamic range of RF fiber-optic links. The authors present both a perturbational theory and measured harmonic data for a p-i-n photodiode operated at very high power densities which show that this and other detector nonlinear effects need not seriously compromise link performance. In particular, neither transit-time nor static nonlinearities in p-i-n photodiodes need limit the dynamic range of fiber-optic links operating below 5 GHz. The fact that the theoretical bandwidth of the photodiode, with all parasitic capacitance and inductance ideally removed, is 17 GHz, suggests that comparable spur-free performance should be achievable at X and Ku-band frequencies, once packaging parasitics are reduced