Occupational injuries among working adolescents in New York State

OBJECTIVE: To determine the number, distribution, determinants, and health consequences of occupational injuries among working adolescents in New York State. DESIGN: A retrospective, population-based analysis of New York State workers' compensation award data and the Annual Demographic File, a supplement to the US Bureau of the Census Current Population Survey. PARTICIPANTS: Adolescents, aged 14 through 17 years, who received workers' compensation awards for occupational injury from 1980 through 1987. MAIN OUTCOME MEASURES: (1) Numbers, types, and rates of occupational injuries in working adolescents by age, sex, industry, and occupation; (2) health consequences of injury, especially disability and death; and (3) secular trends in injury award rates. RESULTS: A total of 9656 adolescents were compensated for occupational injuries; 4201 compensated adolescents (43.5%) suffered permanent disability; 31 working adolescents died. The annual mean rate of compensated occupational injury was 28.2 per 10,000 adolescent workers. Rates were higher in males than in females and ranged from 8.2 per 10,000 in 14-year-old male workers to 46.8 per 10,000 in 17-year-old male workers. Highest rates by industry were seen in manufacturing (49.0/10,000 adolescent workers) and agriculture (46.2/10,000). Unskilled labor was the most dangerous occupation (52.3/10,000). CONCLUSION: Occupational injuries are a substantial and underrecognized contributor to the continuing epidemic of injury among adolescents.     

Selective employment of chemokine receptors as human immunodeficiency virus type 1 coreceptors determined by individual amino acids within the envelope V3 loop

The chemokine receptor CCR5 acts as an essential cofactor for cell entry by macrophage-tropic human immunodeficiency virus type 1 (HIV-1) strains, whereas CXCR4 acts as an essential cofactor for T-cell-line-adapted strains. We demonstrated that the specific amino acids in the V3 loop of the HIV-1 envelope protein that determine cellular tropism also regulate chemokine coreceptor preference for cell entry by the virus. Further, a strong correlation was found between HIV-1 strains classified as syncytium inducing in standard assays and those using CXCR4 as a coreceptor. These data support the hypothesis that progressive adaptation to additional coreceptors is a key molecular basis for HIV-1 phenotypic evolution in vivo.     

Clozapine reduces rehospitalization among schizophrenia patients

Diabetes mellitus positive for antibodies to glutamate decarboxylase is heterogeneous as far as the degree of impairment of endogenous insulin release, though antibodies to glutamate decarboxylase are the most useful marker for future insulin deficiency. To investigate what determines the prognosis of diabetes mellitus positive for antibodies to glutamate decarboxylase, we measured HLA-DRB1 alleles in three groups: 77 cases of insulin-dependent diabetes mellitus (IDDM), 44 of non-insulin-dependent diabetes mellitus (NIDDM) with secondary failure of oral hypoglycemic therapy, and 22 of NIDDM well controlled by diet and/or sulfonylurea agents. The proportion of susceptible and resistant alleles to IDDM determined the degree of insulin deficiency, and comparison of IDDM to NIDDM well controlled by diet and/or sulfonylurea agents revealed significant differences in DRB1*0405 (P < 0.05; RR = 2.82 and RR = 0.89, respectively) and DRB1*1502 (P < 0.001; RR = 0.02 and RR = 2.19, respectively). This study revealed that HLA-DRB1 alleles contribute to determining the prognosis of Japanese diabetes mellitus positive for antibodies to glutamate decarboxylase.     

Insulin propeptides in conditions associated with insulin resistance in humans and their relevance to insulin measurements

Routine insulin assays measure not only biologically active insulin but also the relatively inactive propeptides, proinsulin and desdipeptide proinsulin. Such measurements may be misleading if insulin propeptide levels are increased, as has been reported in patients with non-insulin-dependent diabetes mellitus (NIDDM). Inferences regarding insulin resistance, based on hyperinsulinemia, could thus be invalidated where routine insulin assays have been used. We have measured plasma insulin levels using a routine assay, together with measurements of the major circulating insulin propeptides, intact proinsulin and des 31,32proinsulin, in various clinical situations associated with apparently increased insulin levels and insulin resistance. Major increases of insulin propeptide levels relative to insulin levels were not seen in obese subjects or in patients taking oral contraceptives or danazol, or in obese subjects compared with non-obese controls. Although the insulinemic responses observed with routine radioimmunoassay in these situations associated with insulin resistance are not confounded by major changes in the proportion of circulating insulin propeptides, further studies will be necessary to validate investigations in other insulin-resistant states.     

Resistance to atracurium in rats with experimental inflammation: role of protein binding

The influence of altered protein binding on the neuromuscular effect of atracurium has been studied in rats with experimental inflammation induced by subcutaneous injection of turpentine oil. Doses of atracurium ranging from 0.45 to 1.5 mg.kg-1 were administered to control (n = 30) and to experimental inflammation induced rats (n = 30). Neuromuscular transmission was monitored by recording the twitch tension of the tibialis-anterior muscle elicited by stimulation of the sciatic nerve. Three effect parameters were recorded: (i) intensity of the effect, measured as percentage depression of baseline twitch tension, (ii) duration of drug action (min) and (iii) recovery time (min). The dose-intensity of the effect relationship was modelled using a sigmoid Emax model. The ED50 (effective dose eliciting 50% of the maximum effect) was significantly increased (P < 0.01) in the inflammation group as compared to the control group (0.94 vs. 0.68 mg.kg-1). This change was reflected in a shift of the dose-response curve to the right in the pretreated rats. For equipotent doses ED95 (defined as the effective dose eliciting 95% of maximum effect), no differences were found in recovery time and duration of action between the two groups of rats. Mucoproteins levels (index of alpha 1-acid glycoprotein (AAG) and protein binding were significantly increased in rats with experimental inflammation as compared to control rats. Based on these results, altered serum protein binding of atracurium appears to be responsible, at least in part, for the resistance to atracurium.     

Algorithms for Bayesian background-subtracted Fourier darkfield imaging.

Formal consideration of prior information on the Fourier amplitude of background contrast in an image, using the same Bayesian principles of statistical inference which underlie thermodynamics, allows one to subtract background without favoring only selected parts of frequency space. Without the bias in frequency space which causes periodicity bleeding and mars literal interpretation of Fourier-filtered images, the shape transform of aperiodic objects can be left intact. Algorithms for Bayesian background subtraction from one- and two-dimensional images are presented which further consider, in ad hoc fashion, one's uncertainty about background amplitude. The results help explain the reported success of Fourier truncation, and indicate that Bayesian background-subtracted images can minimize root-mean-square image error, as well as periodicity bleeding, in comparison to Fourier-filtered and Fourier-truncated alternatives.     

Nqr experiments on Sc-Y alloys at very low temperatures

We have performed Nuclear Quadrupole Resonance (NQR) experiments on an alloy of scandium and yttrium. We find that the characteristic resonance frequencies in zero external field are 50 percent larger than in pure scandium. This increase in frequency makes the Sc-Y alloy a better candidate for absolute thermometry below 500 µK. However, the spin-lattice relaxation time of this alloy is more than an order of magnitude longer than in the pure scandium. In addition, we have observed an abrupt increase in the Korringa constant for temperatures below 5mK.