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Objective: To evaluate the reliability and validity of the Chinese Criteria of Health Scale for the elderly people. Methods: A cross-sectional study was performed among older adults of Meiyuan Community in Haidian District, Beijing and Nanwangkong Village in Qingzhou City,Shandong Province during July 2021. Using a cluster sampling method, totally 667 elderly people were investigated by face-to-face interview, using the scale which was formulated after two rounds of the Delphi method and pilot study. The overall scale includes physical health, mental health and social health subscales, including 9, 52 and 15 items, respectively. Four weeks after the survey, 56 elderly people were randomly selected and repeated the survey with the same method. The test-retest reliability, split-half reliability and internal consistency reliability of the scale were evaluated, and the validity was evaluated at the same time, including construct validity and content validity. Results: A total of 710 questionnaires were distributed and 667 valid questionnaires were obtained, with a total effective rate of 93.94%. The score of the overall scale was 79.79±16.22, the scores of the physical health, mental health, social health sub-scores were 41.64±9.76, 26.82±3.92 and 11.34±5.19, respectively. The scale had excellent reliability. In the test-retest reliability, the intraclass correlation coefficient (ICC) of the overall scale and each subscale were 0.766-0.861, and the weighted Kappa values were 0.762-0.817. The Spearman-Brown coefficient of the overall scale and each subscale in the split-half reliability were 0.722-0.855 (all P<0.001). The Cronbach's α coefficients of the overall scale of internal consistency reliability and each subscale were 0.748-0.899, and the Cronbach's α coefficients of each dimension were from 0.709 to 0.963(all P<0.001). At the same time, the scale had good construct validity and content validity. The correlation coefficients between the score of each dimension and its sub-scale were larger, from 0.641 to 0.873 (all P<0.05). The cumulative variance contribution rates of the scale and three subscales were all more than 50% of the approved standard. A total of 11 common factors were extracted, and all the load values of each item on the corresponding factors were ≥0.04. Conclusion: The Chinese Criteria of Health Scale for the elderly people has good validity and excellent reliability. It can be used as a basis for the scientific division of the health status of the elderly, the formulation of relevant policies by the government and the provision of appropriate health services for the elderly.
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População do Leste Asiático , Humanos , Idoso , Reprodutibilidade dos Testes , Estudos Transversais , Projetos Piloto , Inquéritos e Questionários , Psicometria/métodos , ChinaRESUMO
Objective: To analyze the gender disparity and relevant factors of frailty in the elderly of communities in Beijing. Methods: From November 2015 to January 2016, 1 557 participants aged 60 and older in four communities of Dongcheng district in Beijing were recruited by cluster sampling. The information of demographic characteristics, social support, economic status, health status, prevalence situation, cognitive function, emotion and comprehensive assessment of the elderly were collected by a self-made questionnaire. The frailty index (FI) model was used to evaluate the frailty of the elderly. Multivariate nonconditional logistic regression model and Fairlie decomposition method were applied to analyze the relevant factors and their contribution rate to the difference between males and females. Results: The age of subjects was (74.5±8.5) years old, ranging from 60-102 years old, among which 641 were males, accounting for 41.2%. The M (Q1, Q3) of FI was 0.09 (0.06, 0.14), among which the value in males was 0.08 (0.05, 0.13), lower than females [0.10 (0.06, 0.15)] (P<0.001).The frail proportion in female was 14.9% (137/916), higher than that of male [8.4% (54/641)] (P<0.001). Multivariate nonconditional logistic regression model analysis demonstrated that common relevant factors associated with frailty in older women and men include: age ≥80 years old, marital status as not married (unmarried, separated, divorced, or widowed), living alone increased the risk of frailty; participating in group activities ≥3 times/week and exercising regularly decreased the risk of frailty (all P<0.05). Fairlie decomposition method showed that the contribution rate of life style, family support, marital status and social support were 32.21%, 15.26%, 8.23% and 4.34%, respectively (all P<0.05). Conclusions: The frailty degree and frailty proportion of elderly women in communities in Beijing were higher than those of men of the same age. The frailty gender difference was related to lifestyle, family support, marital status and social support.
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Fragilidade , Idoso , Idoso de 80 Anos ou mais , Pequim , Exercício Físico , Feminino , Idoso Fragilizado , Fragilidade/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , PrevalênciaRESUMO
The radiation pressure of light can act to damp and cool the vibrational motion of a mechanical resonator, but even if the light field has no thermal component, shot noise still sets a limit on the minimum phonon occupation. In optomechanical sideband cooling in a cavity, the finite off-resonant Stokes scattering defined by the cavity linewidth combined with shot noise fluctuations dictates a quantum backaction limit, analogous to the Doppler limit of atomic laser cooling. In our work, we sideband cool a micromechanical membrane resonator to the quantum backaction limit. Monitoring the optical sidebands allows us to directly observe the mechanical object come to thermal equilibrium with the optical bath. This level of optomechanical coupling that overwhelms the intrinsic thermal decoherence was not reached in previous ground-state cooling demonstrations.
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AIM: The current study aimed to visualize the damage caused by enterolysin A to the cells of sensitive strains and to find out cleavage site within the peptidoglycan moiety of bacterial cell walls. METHODS AND RESULTS: Enterolysin A produced by a local isolate, Enterococcus faecalis B9510 was found to rapidly kill cells of the sensitive strain Lactococcus lactis ssp. cremoris 2144 during 120 min of treatment as compared to the untreated control where no such effect was observed. Transmission electron microscopy of the enterolysin A-treated cells revealed leaking of the cytoplasmic contents ultimately resulting in complete lysis of cell walls. To find the cleavage site, purified cell walls of L. lactis ssp. cremoris 2144, Pediococcus pentosaceus 43201 and Lactobacillus delbrueckii ssp. bulgaricus ATCC 11842 were treated with enterolysin A, and liberated amino acids were derivatized for N and C terminals and analysed using thin layer chromatography on silica gel with isopropanol as solvent. The results showed that enterolysin A cleaves the peptide bonds at two locations within peptidoglycan subunits. The first location is between L-alanine and D-glutamic acid of the stem peptide and the other location is between L-lysine of the stem peptide and D-aspartic acid of the interpeptide bridge. CONCLUSIONS: Enterolysin A cleaves the peptide bonds within the stem peptide as well as in the interpeptide bridge of Gram-positive bacterial cell walls. This gives a possible reason for the broad spectrum of enterolysin A activity. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report identifying the cleavage site of enterolysin A within the cell walls of sensitive bacteria. This will help in identifying potential applications for enterolysin A.
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Antibacterianos/farmacologia , Bacteriocinas/farmacologia , Sequência de Aminoácidos , Antibacterianos/química , Antibacterianos/toxicidade , Bacteriocinas/química , Bacteriocinas/toxicidade , Parede Celular/efeitos dos fármacos , Parede Celular/metabolismo , Enterococcus faecalis/metabolismo , Lactococcus lactis/efeitos dos fármacos , Dados de Sequência Molecular , Pediococcus/efeitos dos fármacos , Peptidoglicano/química , Peptidoglicano/metabolismo , Homologia de Sequência de AminoácidosRESUMO
AIM: This study aimed to develop a simplified chemically defined medium that could sustain the growth and bacteriocin (enterolysin A) production by Enterococcus faecalis B9510. METHODS AND RESULTS: The nutritional requirements of E. faecalis B9510 in a chemically defined medium were determined by single omission experiments. It was observed that eight amino acids (arginine, glycine, histidine, isoleucine, leucine, methionine, tryptophan and valine), three B vitamins (nicotinic acid, Ca-pantothenic acid and pyridoxal) and magnesium sulphate were essential for growth. Based on this information, a Simplified Defined Medium (SDM) was formed consisting of 26 components. Comparison of SDM with M-17 showed that growth and bacteriocin production in SDM was similar to that in M-17. The bacteriocin from SDM was then purified by ultrafiltration. The retentate of ultrafiltration step was analysed by SDS-PAGE and the results showed a single active band in the gel, which was excised and analysed by mass spectrometry, which indicated that the active band was enterolysin A, a cell wall degrading bacteriocin. CONCLUSIONS: A simplified defined medium can be formulated for the growth and bacteriocin production by Enterococcus faecalis, whose efficiency is comparable with that of a complex commercial medium. SIGNIFICANCE AND IMPACT OF THE STUDY: The development of such a medium can be useful for bacteriocin production and subsequent purification in a simplified manner and, therefore, helpful in the identification of novel bacteriocins.
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Bacteriocinas/biossíntese , Meios de Cultura/química , Enterococcus faecalis/metabolismo , Aminoácidos/química , Bacteriocinas/isolamento & purificação , Técnicas Bacteriológicas , Reatores Biológicos , Complexo Vitamínico B/químicaRESUMO
We study the mechanical quality factors of bilayer aluminum-silicon-nitride membranes. By coating ultrahigh-Q Si(3)N(4) membranes with a more lossy metal, we can precisely measure the effect of material loss on Q's of tensioned resonator modes over a large range of frequencies. We develop a theoretical model that interprets our results and predicts the damping can be reduced significantly by patterning the metal film. Using such patterning, we fabricate Al-Si(3)N(4) membranes with ultrahigh Q at room temperature. Our work elucidates the role of material loss in the Q of membrane resonators and informs the design of hybrid mechanical oscillators for optical-electrical-mechanical quantum interfaces.
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Objective: To analyze the relationship between frailty status and the risk of death in the elderly based on the frailty index (FI). Methods: Data from a prospective cohort study conducted between 2005 and 2015 in elderly people of an urban community in Beijing were analyzed. The variables related to health and frailty status based on the 2005 baseline survey and death as outcome variables collected in 2015 were used. A FI model was used to evaluate the correlation between FI and mortality in the elderly people in different age groups was analyzed. Cox regression was applied to evaluate the influence of FI on the risk of death, and Kaplan-Meier curves was used to show the survival rate of different frailty levels in the elderly adults. Results: Of the 1 301 elderly people included in the analysis, 403 died during 2005-2015, with the 10-year mortality rate of 31.0%(403/1 301). The mortality rate of the elderly increased with the increase of FI, but, with the increase of FI value, the rate of mortality increased slowly. The limit value of FI causing death was around 0.70, indicating any new health problem might cause death at this value. Cox regression analysis showed that higher FI was associated with higher risk for death (HR=1.143, 95%CI: 1.034-1.248, P=0.000), and FI was more significantly associated with death than age (HR=1.143 vs. HR=1.048, t=5.827, P=0.000). With the increase of age, the effect of frailty on the risk of death decreased (HR=1.179 to HR=1.120). Kaplan-Meier curves showed that the survival rate of the elderly in all age groups decreased with the increase of frailty (Log-rank=317.812, 354.203, 247.258, all P=0.000). The survival time between different frailty levels in the elderly were significantly different, except for the elderly adults aged ≥80 years with severe frailty level (0.4≤FI<0.5, FI≥0.5, P=0.368). Conclusions: Compared with other evaluation tools of frailty, FI model can better reflect the frailty status of the elderly in communities in Beijing and has a high sensitivity in predicting adverse outcomes such as mortality. In the intervention of frailty in the elderly, focusing on relatively young elderly might be more effective in reducing the adverse outcomes caused by frailty.
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Idoso Fragilizado , Fragilidade , Mortalidade , Idoso , Idoso de 80 Anos ou mais , Pequim/epidemiologia , Idoso Fragilizado/estatística & dados numéricos , Fragilidade/epidemiologia , Humanos , Mortalidade/tendências , Estudos Prospectivos , RiscoRESUMO
Objective: To evaluate the frailty status and understand the relationship between the incidence of fall and frailty status in the elderly in Beijing. Methods: A cross-sectional study was conducted in old people aged ≥60 years in Longtan community of Dongcheng district in Beijing from November 2015 to January 2016. The information about any fall during the past year and frailty status of the elderly were collected with a standardized structured questionnaire in face-to-face interviews. The frailty status of elderly people was assessed with frailty index (FI) method. Logistic regression analysis was used to explore the relationship between fall and frailty status among the elderly. Results: Among 1 557 old people surveyed, the incidence of fall was 17.8% (277/1 557) during the past year. The incidence of fall in women (21.0%, 192/277) was statistically higher than that in men (13.3%, 85/277) (χ(2)=15.288, P=0.000). The median (quartile) value of FI of the elderly surveyed was 0.09 (0.08); and women had a higher FI median value than men [0.10 (0.08) versus 0.08 (0.07)](Z=5.376, P=0.000). The median FI value (quartile range) of 277 old people with history of fall in previous year was 0.12 (0.11), which was higher than the median FI value of 0.08 (0.07) of 1 280 old people without fall history (Z=7.501, P=0.000). Logistic regression analysis showed that higher FI value was associated with more risks for fall; and FI value showed the greatest impact on the incidence and frequency of fall (OR=1.093, 2.234) compared with other related factors of fall, such as age and gender. Conclusion: Frailty status has a greater impact on both incidence and frequency of fall compared with other factors in elderly people in Beijing; more attention should be paid to weak and old adults in the prevention of fall.
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Acidentes por Quedas/estatística & dados numéricos , Idoso Fragilizado , Fragilidade , Adulto , Idoso , Pequim , Estudos Transversais , Feminino , Avaliação Geriátrica , Humanos , Incidência , Masculino , População UrbanaRESUMO
OBJECTIVE: Long noncoding RNAs (lncRNAs) have been reported to participate in many diseases. Fracture healing is one of these ordinary diseases. This study aims to identify how lncRNA HOXA11-AS affects the progression of fracture healing. MATERIALS AND METHODS: RT-qPCR was performed to detect the level of HOXA11-AS. Moreover, function assays including cell growth assay and cell apoptosis assay were performed to explore how HOXA11-AS functions in fracture healing. Furthermore, the interaction between HOXA11-AS and mir-124-3p was studied by RT-qPCR, luciferase assay, and RNA immunoprecipitation assay. Rescue experiments were performed to verify the interaction between HOXA11-AS and mir-124-3p in vitro. RESULTS: In the research, function assays revealed that HOXA11-AS overexpression inhibited cell proliferation, while HOXA11-AS knockdown promoted cell proliferation in vitro. Moreover, HOXA11-AS overexpression promoted cell apoptosis, while HOXA11-AS knockdown inhibited cell apoptosis in vitro. Furthermore, mechanism assays demonstrated that HOXA11-AS acts a ceRNA via sponging mir-124-3p. Rescue assay demonstrated that HOXA11-AS suppressed cell proliferation and promoted cell apoptosis via targeting mir-124-3p. CONCLUSIONS: These results indicate that HOXA11-AS could inhibit cell proliferation and promote cell apoptosis of osteoblast via sponging mir-124-3p, which may offer a new vision for interpreting the mechanism of fracture healing.
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Consolidação da Fratura/genética , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Antagomirs/metabolismo , Apoptose , Sequência de Bases , Linhagem Celular Tumoral , Proliferação de Células , Células HEK293 , Humanos , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Interferência de RNA , RNA Longo não Codificante/antagonistas & inibidores , RNA Longo não Codificante/genética , RNA Interferente Pequeno/metabolismo , Alinhamento de SequênciaRESUMO
OBJECTIVE: To discuss the suitability of frailty index for comprehensive geriatric assessment(FI-CGA)in the elderly in China, and evaluate the application of FI-CGA in China. METHODS: A comprehensive geriatric assessment was conducted among 118 old adults receiving health examination, and frailty index was calculated. Clinical frailty scale(CFS)was also used to evaluate the frail status of the old adults. The correlation between FI-CGA value and CFS level of the old adults was analyzed. RESULTS: The mean value of FI-CGA was 0.19 ± 0.07, and the average level of CFS was 3.11 ± 1.46. Women had higher mean value of FI-CGA and higher CFS level than men(FI-CGA= 0.20 ± 0.02 for women, 0.19 ± 0.07 for men; CFS =3.40 ± 0.55 for women, 3.10 ± 1.48 for men), but the differences had no significance(t=0.270, 0.452, P=0.788, 0.652). The FI-CGA value and CFS level increased with age(F=10.437, 5.651, P=0.000, 0.001); and there was a positive correlation between FI-CGA value and CFS level(r=0.615, P=0.000). CONCLUSION: FI-CGA is an effective model for the quantitative evaluation of the frail status of the elderly, and can be used in the clinical practice of geriatric medicine.
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Idoso Fragilizado/estatística & dados numéricos , Avaliação Geriátrica/métodos , Idoso , China , Avaliação da Deficiência , Feminino , Avaliação Geriátrica/estatística & dados numéricos , Humanos , Masculino , Valor Preditivo dos TestesRESUMO
The triacylglycerol content and the in vivo lipogenesis rates of the liver and the carcass of 12 groups of mice were studied. They were mice of three strains and affected by mutations at three loci: C57BL/6J-ob/ob and normal mice; C57BL/KsJ-db/db and normal mice; and VY/WfL-Avy/a and normal mice. Each type of mice was studied at two body weight levels, before and after the mutants became grossly obese. It was found that the C57BL/6J-ob/ob and the C57BL/KsJ-db/db mice had the characteristics of juvenile type obesity. They had higher lipogenesis rates and accumulated more triacylglycerol when they were young. They gained weight rapidly mainly due to the accumulation of more triacylglycerol as they matured. Their total triacylglycerol content could reach 50% of their body weight. At maturity, their lipogenesis rates had decreased to normal. In contrast, the VY/WfL-Avy/a mice had the characteristics of maturity-onset type obesity. When they were young, they did not have higher lipogenesis rates and had only a moderate amount of triacylglycerol stored. They did not gain weight rapidly as they matured. However, when they reached maturity, their lipogenesis rate did not decrease. Their body triacylglycerol content was about 25% of their weight.
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Lipídeos/biossíntese , Triglicerídeos/metabolismo , Animais , Peso Corporal , Diabetes Mellitus/metabolismo , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Camundongos Obesos , Tamanho do Órgão , Água/metabolismoRESUMO
The thymidylate synthase (TS) gene from Lactococcus lactis has been highly expressed in Escherichia coli. The TS protein was purified by sequential chromatography on Q-Sepharose and phenyl-Sepharose. Six grams of cell pellet yielded 140 mg of homogeneous TS. TS is a highly conserved enzyme, and several of the conserved amino acid residues that have been implicated in catalytic function are altered in L. lactis TS. By use of a 3-dimensional homology model, we have predicted covariant changes that might compensate for these differences. With the large amounts of L. lactis TS now available, studies can be pursued to understand the structure-function relationships of this enzyme compared to other TSs and to confirm the presumed roles of the compensatory changes predicted in the homology model.
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Expressão Gênica , Lactococcus lactis/enzimologia , Timidilato Sintase/genética , Sequência de Aminoácidos , Sítios de Ligação , Cristalização , Escherichia coli/genética , Concentração de Íons de Hidrogênio , Lactococcus lactis/genética , Modelos Moleculares , Dados de Sequência Molecular , Estrutura Molecular , Concentração Osmolar , Proteínas Recombinantes , Relação Estrutura-Atividade , Timidilato Sintase/química , Timidilato Sintase/isolamento & purificaçãoRESUMO
The genetic basis of hyperactivity of the sympathetic nervous system (SNA) in spontaneously hypertensive rats (SHR) was assessed by measuring SNA in animals derived from a backcross (BC) breeding program designed to isolate single gene differences causing changes in blood pressure. Selective breeding of the male hypertensive rats with inbred normotensive female Wistar/Lewis rats yielded progeny with a range of blood pressures, but whose group mean pressures were lower than the group mean pressures of the original SHR. Progressive generations had progressively lower group mean pressures. There was a positive correlation between SNA and mean arterial pressure in BC rats. These results indicate that the genetic defect in SHR may be abnormality in SNA, and the hypertension in these animals is a secondary result of this primary defect. Baroreceptor function was also assessed in SHR and in BC rats. In young (8 to 24 weeks old) SHR, baroreceptor function was similar to that in BC rats, whereas SNA was markedly increased. Only in older (24 to 40 weeks old) SHR was there an abnormality in the gain of baroreceptors. The development of hypertension in SHR therefore appears to be due to increased SNA resulting from a defect in the central nervous system. Changes in baroreceptor function are secondary to the hypertension and occur after the hypertension is established.
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Pressão Sanguínea , Hipertensão/genética , Ratos Endogâmicos/genética , Sistema Nervoso Simpático/fisiologia , Envelhecimento , Animais , Cruzamentos Genéticos , Frequência Cardíaca , Hipertensão/fisiopatologia , Masculino , Pressorreceptores/fisiologia , RatosRESUMO
Because few previous studies have shown the immunohistochemical localization of tryptophan 5-hydroxylase (TPH) in the gastrointestinal tract, we developed a specific antibody against TPH purified from mouse mastocytoma P-815 and stained human and rat gastrointestinal tracts. The specificity of the antibody was examined by Western blotting and by immunohistochemistry in brain sections. Human ileum and colon specimens, rat stomach, duodenum, jejunum, ileum and colon specimens, with and without colchicine treatment were prepared for immunohistochemistry. Immunoelectron microscopic double staining of TPH and serotonin/chromogranin A and immunofluorescence double staining of TPH and serotonin were performed to identify the cell types. Epithelial enterochromaffin (EC) cells, mast cells in the lamina propria and submucosa, and varicose fibers in the submucosa and muscle layer showed positive immunoreactivity in all segments examined from human and normal rat specimens. In colchicine-treated rat specimens, nerve cell bodies in the myenteric plexus were stained. Because the antibody does not cross react with tyrosine hydroxylase as defined in Western blotting or brain sections, these positive structures may contain TPH. The present results show evidence that EC cells, mast cells, and nerve cell bodies and fibers in the gastrointestinal tracts of both the human and the rat contain TPH and therefore may have the ability to synthesize serotonin from tryptophan.
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Sistema Digestório/enzimologia , Triptofano Hidroxilase/análise , Animais , Epitopos , Feminino , Imunofluorescência , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Microscopia Imunoeletrônica , Células PC12 , Ratos , Células Tumorais CultivadasRESUMO
The effectiveness of central parenteral nutrition (CPN) versus peripheral parenteral nutrition (PPN) plus enteral nutrition in reversing protein-energy malnutrition was evaluated in 19 children (nine CPN, 10 PPN) with advanced neuroblastoma or Wilms' tumor. Weekly dietary, anthropometric, and biochemical measurements were compared for 15 patients (eight CPN, seven PPN) who completed more than 25 days of nutrition support. The groups had similar mean energy and protein intakes (CPN: 95 +/- 5% of healthy children, 2.5 +/- 0.3 g/kg; PPN: 102 +/- 5% of healthy children, 2.9 +/- 0.3 g/kg). Increases in weight (p less than 0.001), subscapular skinfold thickness (p less than 0.001), albumin (p less than 0.05), and transferrin (p less than 0.05) for the first 28 days were significant and did not differ between groups. Fever, sepsis, elevated SGOT, and severe anemia occurred with both CPN and PPN. PPN resulted in subcutaneous infiltrations and more psychological trauma. PPN with enteral nutrition seems most appropriate for short term intravenous nutrition support or as a temporary substitute for CPN; CPN is preferred for long-term support.
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Nutrição Enteral/normas , Neoplasias Renais/terapia , Neuroblastoma/terapia , Nutrição Parenteral/normas , Desnutrição Proteico-Calórica/terapia , Tumor de Wilms/terapia , Peso Corporal , Criança , Pré-Escolar , Feminino , Humanos , Neoplasias Renais/complicações , Masculino , Neuroblastoma/complicações , Nutrição Parenteral/efeitos adversos , Nutrição Parenteral/métodos , Nutrição Parenteral Total/normas , Desnutrição Proteico-Calórica/complicações , Dobras Cutâneas , Tumor de Wilms/complicaçõesRESUMO
Sixty-four patients with possible, probable, or definite multiple sclerosis (McAlpine criteria) were clinically evaluated using the expanded disability status scale (EDSS) and Scripps neurologic rating scale (NRS). All were examined with a 0.15T magnetic resonance scanner using T2- and T1-weighted images. Correlations between EDSS and NRS scores and severity of disease detected on magnetic resonance imaging were determined. Significant correlations existed between EDSS and NRS with magnetic resonance ratings. Moderate correlations were observed in the motor, cerebellar, and brainstem subgroups of the clinical scales. Significant low correlations existed in the mood/mentation, vision (optic nerves), and bowel/bladder subgroups. Clinical and neuroimaging limitations may account for the lack of higher correlations. Significant correlations suggest the utility of magnetic resonance imaging in monitoring disease progression, and it may prove to be the technique of choice in following up patients with multiple sclerosis.
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Encéfalo/patologia , Espectroscopia de Ressonância Magnética , Esclerose Múltipla/diagnóstico , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
MRI of the brain, peripheral blood (PB) T cell subsets and B cells, CSF T cell subsets, CSF IgG concentration and incidence of CSF oligoclonal bands (OB), and plasma cells were studied in 32 clinically suspected MS patients. The CSF in MS patients with MRI lesions showed increased IgG concentration and higher incidence of plasma cells and OB compared with those without MRI lesions. In PB, the percentage of kappa light-chain positive B cells was significantly increased in patients with abnormal MRI as compared with controls. The correlation of MRI of the head and immunologic studies in MS will be helpful in better understanding the pathogenesis and dynamics of the disease.
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Espectroscopia de Ressonância Magnética , Esclerose Múltipla/diagnóstico , Adulto , Feminino , Humanos , Imunoglobulina G/líquido cefalorraquidiano , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/imunologia , Linfócitos T/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Reguladores/imunologiaRESUMO
The gene encoding the bifunctional dihydrofolate reductase (DHFR) and thymidylate synthase (TS) of Trypanosoma brucei brucei has been isolated and expressed in Escherichia coli, and the enzyme has been purified and characterized. The coding sequence of the DHFR-TS is 1581 nt, encoding a 527-amino-acid protein of 58,505 Da. The gene was expressed under control of the trc promoter in pKK233-2. The resulting expression plasmid conferred trimethoprim resistance to E. coli DH5 alpha and complemented the TS deficiency in chi 2913recA cells indicating the presence of active DHFR and TS. DHFR-TS was purified by methotrexate-Sepharose chromatography. In addition to the full-length enzyme, the purified enzyme contained 31 and 31.5-kDa forms of the enzyme that cross-reacted with anti-L. major DHFR-TS antibodies; one was truncated at the N- and C termini, and the other at only the C terminus. Despite the presence of sufficient TS for complementation, TS activity was not detectable in the crude extract or in the final purified enzyme preparation. Although the majority of the enzyme appears to be full length, it is possible that the TS domain has been degraded by one of more residues, which would inactivate the ability to synthesize thymidylate. Kinetic analysis of DHFR yielded kcat and Km values similar to those of related enzymes. The T. brucei DHFR has Ki values for antimicrobial antifolates pyrimethamine and trimethoprim which are significantly lower than the closely related T. cruzi or L. major DHFRs or than human DHFR.
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Genes de Protozoários , Proteínas de Protozoários/genética , Tetra-Hidrofolato Desidrogenase/genética , Timidilato Sintase/genética , Trypanosoma brucei brucei/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Indução Enzimática , Antagonistas do Ácido Fólico/farmacologia , Humanos , Cinética , Dados de Sequência Molecular , Proteínas de Protozoários/antagonistas & inibidores , Proteínas de Protozoários/metabolismo , Pirimetamina/farmacologia , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Especificidade da Espécie , Tetra-Hidrofolato Desidrogenase/metabolismo , Timidilato Sintase/antagonistas & inibidores , Timidilato Sintase/metabolismo , Trimetoprima/farmacologia , Trypanosoma brucei brucei/enzimologia , Trypanosoma cruzi/genéticaRESUMO
The effect of nonnutritive sucking during gavage feeding on nutritional outcome and gastrointestinal transit time was evaluated in 18 premature appropriate for gestational age infants whose birth weights were less than or equal to 1,400 g and gestational ages were less than or equal to 30 weeks. Infants were randomized to a treatment (nonnutritive sucking infants received a pacifier for 30 minutes with each feeding, 12 times per day until they reached a weight of 1,500 g, eight times per day thereafter) or control (no pacifier) group. The nine nonnutritive sucking (five girls, four boys) and nine control (five girls, four boys) infants were treated for 14 days. Infants were without medical complications and were fed a single premature formula by intermittent gastric gavage at exactly 120 kcal/kg/d throughout the study period. Weight gain, linear growth, subscapular and triceps skinfold, and arm circumference accretions were assessed weekly. Serum proteins (albumin, prealbumin, retinol-binding protein, and transferrin) were measured weekly. Gastrointestinal transit times were measured weekly using carmine red markers. In contrast to previous studies, these data indicate no apparent effect of nonnutritive sucking on growth outcome, serum proteins, or gastrointestinal transit time in growing, very low birth weight infants when nutrient intake was controlled. In a subgroup of eight boys (four nonnutritive sucking, four control), energy and fat excretions were determined from 72-hour fecal collections and energy expenditure was estimated from six-hour cumulative heart rate measurements. Neither excretion of fat and calories nor estimated energy expenditure was affected significantly by nonnutritive sucking in this subgroup of baby boys. Fat excretion correlated well (r = .987) with energy excretion.
Assuntos
Cuidado do Lactente , Recém-Nascido de Baixo Peso/crescimento & desenvolvimento , Comportamento de Sucção/fisiologia , Metabolismo Energético , Feminino , Trânsito Gastrointestinal , Humanos , Alimentos Infantis , Recém-Nascido , Recém-Nascido Prematuro/crescimento & desenvolvimento , Masculino , Estudos Prospectivos , Distribuição AleatóriaRESUMO
Several methods have been proposed for the separation and labeling of white blood cells for the diagnosis of suspected infection. We retrospectively compared 105 patients imaged with 111In purified granulocytes (GRAN) to 106 patients imaged with 111In mixed leukocytes (MIX). We found that in acute infection the sensitivity of GRAN and MIX were both high and not statistically different. In chronic infections the sensitivities were lower than for acute infections. Again, there was no significant difference between GRAN and MIX with the borderline significant exception of MIX being superior to GRAN in chronic soft tissue infections (p = 0.06). We then had independent observers blindly grade the degree of lesion visualization. We found that delayed images visualized the lesions better than early images (p = 0.0001) and acute infection was better visualized than chronic infection (p = 0.03). We concluded that, in routine clinical practice, MIX is probably the agent of choice for three reasons: (a) easier preparation, (b) comparable sensitivity in acute infection and, (c) borderline superior sensitivity in chronic infection.