Ratiometric Detection of Glutathione Based on Disulfide Linkage Rupture between a FRET Coumarin Donor and a Rhodamine Acceptor

Abnormal levels of glutathione, a cellular antioxidant, can lead to a variety of diseases. We have constructed a near-infrared ratiometric fluorescent probe to detect glutathione concentrations in biological samples. The probe consists of a coumarin donor, which is connected through a disulfide-tethered linker to a rhodamine acceptor. Under the excitation of the coumarin donor at 405 nm, the probe shows weak visible fluorescence of the coumarin donor at 470 nm and strong near-infrared fluorescence of the rhodamine acceptor at 652 nm due to efficient Forster resonance energy transfer (FRET) from the donor to the acceptor. Glutathione breaks the disulfide bond through reduction, which results in a dramatic increase in coumarin fluorescence and a corresponding decrease in rhodamine fluorescence. The probe possesses excellent cell permeability, biocompatibility, and good ratiometric fluorescence responses to glutathione and cysteine with a self-calibration capability. The probe was utilized to ratiometrically visualize glutathione concentration alterations in HeLa cells and Drosophila melanogaster larvae.     

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.     

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.     

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.     

Fathers and children: Predicting the quality and quantity of fathering.

This study looked at the quality and quantity of interactions between fathers and their firstborn 5-year-olds from the perspective of the family as a developmental interdependent system. The goals were to identify predictors of men's parenting from men's own adaptation (direct effects) and from their wives' characteristics (indirect effects), both measured during the expectancy. Twenty-three families from the Boston University Pregnancy and Parenthood Project made up the sample. Measures included self-report scales, observations, and semistructured interviews. Several of men's psychological characteristics, particularly their autonomy and job satisfaction, predicted their play time and the quality of their interactions with their children. Women's autonomy, occupation, and age in the expectancy predicted men's caretaking and weekday time involvement with their 5-year-olds. We suggest that the findings can best be explained by the concepts of complementarity and identification. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Differential Display of Investigative Behavior Permits Discrimination of Scent Signatures from Familiar and Unfamiliar Socially Dominant Female Marmoset Monkeys (Callithrix jacchus)

The hypothesis was tested that marmosets have differential displays of investigatory behavior towards circumgenital scent marks from socially dominant females based on degree of familiarity. In a series of two-choice behavioral discrimination bioassays, dominant males together with subordinate and dominant females were presented concurrently with scent secretions from familiar versus unfamiliar dominant females, and their investigative behaviors towards the scent were recorded. Test animals directed significantly different amounts of investigative behaviors towards familiar versus unfamiliar scents when the scent stimuli involved complete circumgenital scent marks, glandular secretion only, or urine only. When animals discriminated between the two scent samples, they did so by directing significantly increased amounts of behavior to scent from unfamiliar females. Chemical cues promoting differential displays of behavior to familiar versus unfamiliar scents appeared to be volatile in nature and were effective in the scent mark for at least one day following deposition. The reliable ability of marmosets to consistently discriminate between odors from familiar versus unfamiliar dominant females provides strong circumstantial evidence that individual female marmosets have distinct chemical signatures. The ability of marmosets to discriminate the odor from familiar versus unfamiliar dominant females may be important in the context of intergroup relations.     

Towards Focused Plan Monitoring: A Technique and an Application to Mobile Robots

Until recently, techniques for AI plan generation relied on highly restrictive assumptions that were almost always violated in real-world environments; consequently, robot designers adopted reactive architectures and avoided AI planning techniques. Some recent research efforts have focused on obviating such assumptions by developing techniques that enable the generation and execution of plans in dynamic, uncertain environments. In this paper, we discuss one such technique, rationale-based monitoring, originally introduced by Veloso, Pollack, and Cox (Proceedings for the Fourth International Conference on AI Planning Systems, Pittsburgh, PA, 1998, pp. 171–179) and we describe our use of it in a simple mobile robot environment. We review the original approach, describe how it can be adapted for a causal-link planner, and provide experimental results demonstrating that it can lead to improved plans without consuming excessive overhead. We also describe our use of rationale-based monitoring in a mobile robot office-assistant project currently in progress.