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981.
Miller M, Wong WK, Wu J, Cavenett S, Daniels L, Crotty M. Upper-arm anthropometry: an alternative indicator of nutritional health to body mass index in unilateral lower-extremity amputees?

Objective

To evaluate the utility of body mass index (BMI) and corrected-arm-muscle area (CAMA) as measures of nutritional health for lower-limb amputees attending prosthetics clinics.

Design

Cross-sectional study.

Setting

Prosthetics clinic in Australia.

Participants

Unilateral lower-extremity amputees (N=58; age range, 21-91y; 37 transtibial, 21 transfemoral) attending a regional prosthetics clinic between May and November 2003.

Interventions

Not applicable.

Main Outcome Measures

Weight (without prosthesis), corrected and uncorrected for the amputated limb was used with height estimated from knee height to calculate corrected BMI (cBMI) and uncorrected BMI (uBMI). CAMA was calculated using the mean of triplicate mid-upper-arm circumference (MUAC) and triceps skinfold thickness (TST) measurements. The Mini Nutritional Assessment (MNA) and Assessment of Quality of Life were administered according to recommended protocols. The Pearson correlation was used to determine the strength and significance of associations between variables, and bivariate regression analyses were performed to determine whether an association existed between the nutritional variables (BMI, CAMA, MNA) and quality of life (QOL).

Results

There were no statistically significant differences in the measures of nutritional health according to site (transtibial, transfemoral) of amputation. MUAC, TST, and CAMA all showed moderate to high positive correlations (r range, .541−.782) with both cBMI and uBMI. The strength of the relationship between the MNA and cBMI/uBMI was weaker (r=.383, r=.380, respectively) but remained positive and statistically significant (P=.003). QOL was not associated with cBMI or uBMI but was related to CAMA (β=−.132; P=.030) and MNA (β=−.561; P=.017).

Conclusions

For persons with unilateral lower-extremity amputation, measurement of upper-arm anthropometry may be a more useful indicator of nutritional health and its consequences than BMI.  相似文献   
982.
BACKGROUND: Cobalamin (Cbl) and folate deficiencies and gene polymorphism of key enzymes or carriers can impair homocysteine metabolism and may change the serum values of S-adenosylmethionine (SAM) and S-adenosylhomocysteine (SAH). We investigated the nutritional and genetic determinants for total homocysteine (tHcy), methylmalonic acid (MMA) and SAM/SAH in healthy Brazilian childbearing-age women. METHODS: Serum concentrations of Cbl, folate, red blood cell folate, ferritin, tHcy, MMA, SAM, SAH and other metabolites were measured in 102 healthy unrelated women. The genotypes for MTHFR C677T, MTHFR A1298C, MTR A2756G, MTRR A66G, TC2 C776G, TC2 A67G and RFC1 A80G gene polymorphisms were identified by PCR-RFLP. RESULTS: Serum folate and Cbl were inversely correlated with tHcy and serum MMA, respectively. Cbl deficiency was associated with increased MMA and reduced alpha-aminobutyrate, serine and N-methylglycine concentrations. No variable was associated with SAM/SAH ratio. In addition, gene polymorphisms were not selected as determinants for tHcy, MMA and SAM/SAH ratio. Iron, Cbl and folate deficiencies were found respectively in 30.4%, 22.5% and 2.0% of individuals studied. CONCLUSIONS: There was a high frequency of Cbl and iron deficiency in this group of childbearing-age women. Serum folate and Cbl were the determinants of serum tHcy and MMA concentration, respectively.  相似文献   
983.
Neurodegeneration in familial amyotrophic lateral sclerosis (ALS) is associated with enhanced redox stress caused by dominant mutations in superoxide dismutase-1 (SOD1). SOD1 is a cytosolic enzyme that facilitates the conversion of superoxide (O(2)(*-)) to H(2)O(2). Here we demonstrate that SOD1 is not just a catabolic enzyme, but can also directly regulate NADPH oxidase-dependent (Nox-dependent) O(2)(*-) production by binding Rac1 and inhibiting its GTPase activity. Oxidation of Rac1 by H(2)O(2) uncoupled SOD1 binding in a reversible fashion, producing a self-regulating redox sensor for Nox-derived O(2)(*-) production. This process of redox-sensitive uncoupling of SOD1 from Rac1 was defective in SOD1 ALS mutants, leading to enhanced Rac1/Nox activation in transgenic mouse tissues and cell lines expressing ALS SOD1 mutants. Glial cell toxicity associated with expression of SOD1 mutants in culture was significantly attenuated by treatment with the Nox inhibitor apocynin. Treatment of ALS mice with apocynin also significantly increased their average life span. This redox sensor mechanism may explain the gain-of-function seen with certain SOD1 mutations associated with ALS and defines new therapeutic targets.  相似文献   
984.
blaCTX-M genes, particularly blaCTX-M-15, are the dominant extended-spectrum β-lactamase (ESBL) genes among clinical isolates of Escherichia coli and Klebsiella pneumoniae in Sydney, Australia, where we also found one example of blaCTX-M-62, encoding a novel enzyme conferring ceftazidime resistance. ESBL genes were present in diverse community isolates and in a variety of associated conjugative plasmids.  相似文献   
985.
This study evaluated a computerized intervention designed to assist high school-aged smokers to consider not smoking and move forward in the "Stages of Change." A pretest-posttest pilot was conducted with 121 high school students who completed self-reported questionnaires that provided information about smoking history and exposure, smoking dependence, stage of change, and social support. Following baseline assessment, the experimental group (n = 61) completed four, 30-minute computerized sessions known as the Computerized Adolescent Smoking Cessation Program (CASCP). Immediately following completion of the program and 1 month later, the experimental subjects were reassessed. Control subjects completed baseline assessment and were reassessed 4 to 5 weeks later. CASCP increased the number of quit attempts. At 1 month after the intervention, 20% of the experimental group quit smoking. Of those subjects who did not quit smoking, nicotine dependence and the number of cigarettes smoked daily decreased, which decreased their nicotine dependence. Overall, there was a forward movement in the experimental group's stage of change. CASCP was found to be an effective and inexpensive intervention that motivates adolescent smokers to consider smoking cessation, move forward in the stage of change, and decrease nicotine dependence.  相似文献   
986.
Those who attempt suicide have often been described as 'crying for help', and there are implications if such cries are not taken seriously. This paper examines how users of an Internet forum for 'suicidal thoughts' work up their authenticity in their opening posts, and how these are responded to by fellow forum users. Data were taken from two Internet forums on suicide over a period of one month and were analysed using discursive psychology. The analysis demonstrates that participants display their authenticity through four practices: narrative formatting, going 'beyond' depression, displaying rationality and not explicitly asking for help. Furthermore, both initial and subsequent posts worked up identities as being psychologically 'on the edge' of life and death. The analysis suggests that the forum in part works as a site for suicidal identities to be tested out, authenticated and validated by individuals. We conclude with some suggestions for the supportive work of suicide 'postvention'.  相似文献   
987.
Recent feminist analyses, particularly from those working within a poststructuralist framework, have highlighted a number of historically located and contradictory socio-cultural constructions and practices which women are faced with when negotiating infant feeding, especially breastfeeding, within contemporary western contexts. However, there has been little explicit analysis of the practice of expressing breast milk. The aim of this article is to explore the embodied practice of expressing breast milk. This is done by analysing, from a feminist poststructuralist perspective, discourse surrounding expressing breast milk in sixteen first time mothers' accounts of early infant feeding. Participants were recruited from a hospital in the South Midlands of England. The data are drawn from the first phase of a larger longitudinal study, during which mothers kept an audio diary about their breastfeeding experiences for seven days following discharge from hospital, and then took part in a follow-up interview. Key themes identified are expressing breast milk as (i) a way of managing pain whilst still feeding breast milk; (ii) a solution to the inefficiencies of the maternal body; (iii) enhancing or disrupting the ‘bonding process’; (iv) a way of managing feeding in public; and (v) a way to negotiate some independence and manage the demands of breastfeeding. Links between these and broader historical and socio-cultural constructions and practices are discussed. This analysis expands current feminist theorising around how women actively create the ‘good maternal body’. As constructed by the participants, expressing breast milk appears to be largely a way of aligning subjectivity with cultural ideologies of motherhood. Moreover, breastfeeding discourses and practices available to mothers are not limitless and processes of power restrict the possibilities for women in relation to infant feeding.  相似文献   
988.
989.
990.
OBJECTIVE: Recommendations for improving care include increased patient-clinician collaboration, patient empowerment, and greater relational continuity of care. All rely upon good clinician-patient relationships, yet little is known about how relational continuity and clinician-patient relationships interact, or their effects on recovery from mental illness. METHODS: Individuals (92 women, 85 men) with schizophrenia, schizoaffective disorder, affective psychosis, or bipolar disorder participated in this observational study. Participants completed in-depth interviews detailing personal and mental health histories. Questionnaires included quality of life and recovery assessments and were linked to records of services used. Qualitative analyses yielded a hypothesized model of the effects of relational continuity and clinician-patient relationships on recovery and quality of life, tested using covariance structure modeling. RESULTS: Qualitative data showed that positive, trusting relationships with clinicians, developed over time, aid recovery. When "fit" with clinicians was good, long-term relational continuity of care allowed development of close, collaborative relationships, fostered good illness and medication management, and supported patient-directed decisions. Most valued were competent, caring, trustworthy, and trusting clinicians who treated clinical encounters "like friendships," increasing willingness to seek help and continue care when treatments were not effective and supporting "normal" rather than "mentally ill" identities. Statistical models showed positive relationships between recovery-oriented patient-driven care and satisfaction with clinicians, medication satisfaction, and recovery. Relational continuity indirectly affected quality of life via satisfaction with clinicians; medication satisfaction was associated with fewer symptoms; fewer symptoms were associated with recovery and better quality of life. CONCLUSIONS: Strong clinician-patient relationships, relational continuity, and a caring, collaborative approach facilitate recovery from mental illness and improved quality of life.  相似文献   
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