Linking perceptions of the community to behavior: are protective social factors associated with physical activity?

Although the relationship of psychosocial factors to physical activity has been explored, there is increased interest in how perceptions of the community environment influence behavior. However, few methodological studies have incorporated perceptions of the social and community environment (protective social factors) or addressed key measurement issues. Computer-assisted telephone interviews were administered to a national sample of 1,818 U.S. adults. Unadjusted and multivariate-adjusted odds ratios were calculated to compare active and inactive participants by Protective Social Factors (PSF) scores and selected sociodemographics. Confirmatory factor analysis and reliability analysis suggested strong PSF scale psychometric properties (alpha = .92). After adjustment for potential confounders, a 10-point rise in the PSF score resulted in a 12% increased likelihood of meeting Centers for Disease Control and Prevention/American College of Sports Medicine recommendations. Additional analyses indicated that greater perceived PSFs were associated with meeting these recommendations among Whites but not among African Americans.     

Use of Sentinel blood culture system for analysis of specimens from potentially infected prosthetic joints.

The Sentinel blood culture system was used for the analysis of 657 specimens from infected prosthetic joints and blood cultures (83 from prosthetic joints and 574 from standard blood cultures). The positivity rate was similar for specimens from prosthetic joints and blood cultures (18% compared with 14%). However, there was an unacceptable rate of false positive results with specimens from prosthetic joints (58% compared with 8%). This high false positivity rate was due to (i) prolonged incubation and (ii) the lack of blood in these specimens. It is therefore recommended that the Sentinel system should only be used for the initial seven days of incubation of specimens taken from prosthetic joints. Further incubation should take place in a standard incubator and a terminal subculture performed after 21 days.     

Two classes of spontaneous GABA-mediated miniature synaptic currents in cultured rat hippocampal neurons.

Amplitude and time course of spontaneous gamma-aminobutyric acid (GABA)-mediated miniature postsynaptic currents (MPSCs), recorded in cultured embryonic hippocampal neurons in presence of either tetrodotoxin (TTX) or increased external [Mg2+/Ca2+] ratio, revealed that they form two classes. The distribution of the most commonly recorded MPSCs was skewed both in terms of peak amplitude and rise-time (skew-MPSCs, mode: 70-120 pS). Another, less frequent class (mode: 1-3 nS) formed bell-shaped (bell-MPSCs) amplitude and rise-time distributions. MPSC initial slope did not correlate with rise time, indicating that smaller MPSCs were not electrotonically attenuated. Bell-MPSCs did not result from the integration of skew-MPSCs and both classes appeared to be composed of subunits.     

Intra-arterial chemotherapy for head and neck cancer. An update on the totally implantable infusion pump

Intra-arterial chemotherapy for the treatment of localized malignant neoplasms in the head and neck is an appealing approach for several reasons. Perhaps the most important is the possibility of obtaining a regional advantage such that an increased drug concentration is delivered systemically. The patient may, therefore, be spared systemic toxicity. We report our accumulated experience using a totally implantable infusion pump in 37 patients. A total of 42 pumps were implanted: 28 single-catheter pumps and 14 dual-catheter pumps. Radionuclide imaging demonstrated total perfusion of the tumor in all patients. A combination of cisplatin (50 to 100 mg/m2) and floxuridine (0.01 to 0.045 mg/kg/d) was used to treat 26 patients. For these heavily pretreated patients, we observed a 43% complete and partial response rate in the subgroup of patients with squamous cell carcinoma. These results are comparable with those reported for these drugs administered systemically and for other drug combinations tested in the treatment of recurrence disease.     

Haemodynamic assessment of the femoropopliteal segment: comparison of pressure and Doppler methods using ROC curve analysis

Combined aorto-iliac and femoropopliteal vascular disease remains a problem in vascular surgery. Arteriography does not provide information on the relative contributions of the two lesions to the presenting symptoms. Aorto-iliac haemodynamics may reveal occult aorto-iliac disease but does not show whether combined proximal and distal reconstruction will be required to provide symptomatic relief. Haemodynamic assessment of both segments may help in this respect. A haemodynamic assessment of the femoropopliteal segment of 72 limbs in 38 patients is reported. The segmental pressure drop between a common femoral arterial cannula and a below-knee occlusion cuff is compared with a non-invasive Doppler method combining both transit time and damping factor. Comparison is made using receiver operating characteristic (ROC) curve analysis. The measurement of segmental pressure drop is more accurate than the Doppler method in detection of femoropopliteal stenoses of greater than 50 per cent of the luminal diameter (P less than 0.05).     

Effect of meal on the physiological and physicochemical actions of potassium citrate

The effect of meals on the physiological and physicochemical actions of potassium citrate was examined in 8 patients with nephrolithiasis maintained on a constant metabolic dietary regimen. Potassium citrate (20 mEq. 3 times per day), whether given with food or on an empty stomach, significantly increased urinary pH, citrate and potassium, and decreased urinary calcium and ammonium. Moreover, potassium citrate decreased urinary saturation of calcium oxalate and uric acid, although it slightly increased that of brushite. However, there was no significant difference in these measures when the drug was given with meals from the time when it was given on an empty stomach. Thus, the effect of potassium citrate on urinary risk factors is unaffected by food.     

Tourette syndrome and neuropsychological performance

This study examined performance on a battery of neuropsychological tests in a sample of 28 patients with Tourette's syndrome (TS). Test scores were converted to age-corrected T-scores to control for the effect of age on test performance. The frequency of abnormal test performances was variable, but more frequent on motor and sensory tasks. Symptom severity as measured by the Tourette Syndrome Global Scale was inversely related to neuropsychological performance. In general, neuropsychological performance was mildly below average. The pattern of performance was similar to previous studies of TS patients.     

Dog bites in urban children

As a result of a perceived increase in pit bull injuries, all children who presented to The Children's Hospital of Philadelphia during 1989 for evaluation of dog bite injuries were prospectively studied. Epidemiologic information was collected from parents, either at the time of visit or by phone on the following day. A total of 168 children were enrolled; the mean age was 8 years. Males outnumbered females 1.5:1. Most (61%) injuries occurred in or around the home and involved dogs known to the patient (77%). Types of injuries included abrasions (33%), punctures (29%), and lacerations (38%). Thirteen bites had associated complications; nine developed infection. Twelve (7%) children required admission to the hospital. More than 12 different purebreeds or cross-breeds were identified as perpetrators, including German shepherds (n = 35), pit bulls (n = 33), rottweilers (n = 9), and Dobermans (n = 7). Most (54%) animals were contained (ie, leashed, fenced, in-house) at the time of injury. Fewer (46%) were provoked prior to biting. Significantly more pit bull injuries (94% vs 43%, P less than .001) were the consequence of unprovoked attacks and involved freely roaming animals (67% vs 41%, P less than .01). Children aged 5 or younger were more likely to provoke animals prior to injury than were older children (69% vs 36%, P less than .001). It is recommended that families with young children be the target of pet safety education and that measures be sought that would lead to early identification of a potentially dangerous dog and restrict ownership.     

Evidence for a decrease in sympathetic control of intestinal function in the aged rat.

The ability of carbachol and isoprenaline to contract and relax respectively the longitudinal layer of ileal smooth muscle has been compared in rats aged six and twenty-four months. The concentration response curve to carbachol did not vary with the age of the animal. In contrast, the ability of isoprenaline to relax longitudinal smooth muscle precontracted with carbachol was significantly (p less than 0.02) reduced in the twenty-four month age group. This reduced response was due to a decrease in the maximal relaxation induced by isoprenaline rather than by a shift to the right of its dose-response curve. These results are discussed in the context of previous histochemical and microscopical studies which have shown a marked reduction in the density of the sympathetic innervation of the rat small intestine in old age.