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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

Bacteriuria asintomática y su relación con mal control glicémico en pacientes diabéticos tipo 2 en un hospital de Callao, Perú

Colán Tello, Cristina Tatiana, Gálvez- Gastelú, Andrea 02 March 2015 (has links)
Objetivo: Determinar la relación entre mal control glicémico y bacteriuria asintomática (BA) en pacientes diabéticos tipo 2. Materiales y Métodos: Se llevó a cabo un estudio transversal analítico que incluyó 356 pacientes diabéticos atendidos en el Hospital Nacional Alberto Sabogal Sologuren (HNASS)durante el 2011 y 2012. Las variables bacteriuria asintomática, hemoglobina glicosilada (HbA1c), creatinina sérica, microalbuminuria, tiempo de diagnóstico, índice de masa corporal (IMC), fecha de última menstruación, antecedente de patología prostática e incontinencia urinaria se obtuvieron de las historias clínicas. Resultados: De 356 pacientes con DM2 se encontró presencia de BA en 51,9% de la población estudiada. Se halló asociación entre HbA1c mayor o igual a 6,5% y la presencia de BA (RP= 3,4, IC 95% 2,2 – 5,2). En el análisis multivariado, la variable control metabólico, ajustada por las variables IMC, género y tiempo de diagnóstico de DM2, estuvo asociada con BA (RP= 3,3, IC 95% 2,2 – 5). Conclusiones: Los valores de HbA1c elevados se encuentran asociados a la presencia de bacteriuria asintomática, por lo cual se recomienda mantener niveles inferiores a 6,5%; con la finalidad de reducir el riesgo de BA y su predisposición a infección urinaria y daño renal. . / Objective: To determine the relationship between bad glycemic control and asymptomatic bacteriuria (AB) in type 2 diabetic patients. Materials and Methods: a cross-sectional study, including 356 diabetic patients treated at NationalHospital Alberto Sabogal Sologuren (HNASS) during the years 2011 and 2012. The variables are asymptomatic bacteriuria, Hemoglobin A glycosylated (HbA1c), serum creatinine, microalbuminuria, time to diagnosis, date last menstrual period, history of prostate pathology and urinary incontinence were obtained from medical records. Results: From 356 patients with DM2 was found 51.9% presence of AB in the study population. Association was found between HbA1c greater than or equal to 6.5% and AB (PR= 3.4, CI95% 2.2 – 5.2). In addition, male gender was found between AB and prostatic syndrome (p <0.05). In multivariate analysis, the variable metabolic control adjusted for BMI variables, gender and time of diagnosis of type 2 diabetes mellitus was associated with AB (PR = 3.3, CI 95% 2.2 – 5). Conclusions: elevated HbA1c values were associated with the presence of AB, so we recommend keeping HbA1c levels <6.5% because AB may predispose the patient to urinary tract infection and possible kidney damage.
142

Efeito da temperatura e alta pressão hidrostática na termodinâmica da dissociação da hemoglobina extracelular / Temperature and high pressure effect on thermodynamic of the extracellular hemoglobin dissociation

Norberto, Douglas Ricardo, 1970- 03 December 2007 (has links)
Orientador: Carlos Francisco Sampaio Bonafé / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-18T11:09:06Z (GMT). No. of bitstreams: 1 Norberto_DouglasRicardo_M.pdf: 4245356 bytes, checksum: 8a2d8041749dec81554527bd8729d8ea (MD5) Previous issue date: 2007 / Resumo: A hemoglobina extracelular de Glossoscolex paulistus (eritrocruorina) foi investigada com respeito ao efeito da temperatura na dissociação induzida por alta pressão hidrostática. O aumento de temperatura e pressão induziu o processo de dissociação, como observado pela significativa diminuição da intensidade de espalhamento de luz. Tais informações foram confirmadas através de HPLC em gel filtração e microscopia eletrônica. Ocorreu uma redução dos valores de energia livre de Gibbs de dissociação indicando um processo predominantemente endotérmico. A variação de entalpia (?H) observada no processo foi de 27,82 MJ/mol de hemoglobina (Hb) e a de entropia (T?S), à temperatura de 293 K, de 23,91 MJ/mol de Hb. Foi encontrada uma redução da mudança de volume de dissociação (?V) de -78,20 para -10,44 mL/mol de subunidade de Hb. Em condições atmosféricas e temperatura de 293 K, a variação da energia interna de dissociação (?U) foi de 27,82 MJ/mol de Hb e da energia livre de Helmholtz, (?A), de 3,92 MJ/mol de Hb. Os resultados da dissociação oligomérica em alta pressão no intervalo de temperatura investigado mostraram a ocorrência de etapas distintas de mudança de estabilidade conformacional. Complementarmente, foi realizado um estudo das interações intersubunidades e da área de exposiçao da proteína ao solvente no processo de dissociação, permitindo a obtenção de importantes dados quantitativos no processo / Abstract: Glossoscolex paulistus extracelluar hemoglobin (erithrocruorin) was studied with respect of thermal effect on the dissociation induced by high hydrostatic pressure. The increase of temperature and pressure led to dissociation process, as observed by the significant decrease in the intensity of light scattering values. Such information was confirmed by HPLC gel filtration and electron microscopy. A predominantly endothermic process was observed with the reduction in the Gibbs free energy of dissociation. The enthalpy change (?H) obtained was of 27,82 MJ/mol of hemoglobin (Hb) and the entropy change (T?S), at a temperature of 273 K, 23,91 MJ/mol of Hb. The estimated volume change of dissociation (?V) decreased from -78,20 to -10,44 mL/mol of subunit of Hb. The change of internal energy of dissociation (?U), at atmospheric conditions and temperature of 293K, was of 27,82 MJ/ mol of Hb and the change of free energy of Helmholtz (?A) was of 3,92 MJ/mol of Hb. The results also indicated that the dissociation of oligomeric Hb at high pressure and at investigated temperature range occurs in distinct steps of conformational stability and allowed to obtain significant quantitative data in the process. In addition, it was studied the subunity interactions and related exposed area of the protein solvent dissociation, attempting to obtain an quantitative description of the process / Mestrado / Bioquimica / Mestre em Biologia Funcional e Molecular
143

Computação inteligente no estudo de variantes de hemoglobina / Intelligent computation applied to the study of hemoglobin variants

Thaís Helena Samed e Sousa 29 October 2004 (has links)
A evolução in vitro é um método laboratorial criado para a evolução de moléculas, principalmente de proteínas. Por meio de mutações, o método busca novas propriedades de moléculas, objetivando criar novas proteínas e, com isso, intensificar o estudo e a cura de doenças, pelo desenvolvimento de novos fármacos. O grande desafio na evolução in vitro é criar o maior número possível de moléculas de proteínas que atinjam propriedades desejadas, uma vez que apenas uma fração infinitesimal das diversidades geradas utilizando-se seqüências de DNA é aproveitada. Para se obter moléculas com funcionalidade adequada por meio dessa técnica, é requerido muito tempo e aporte financeiro. Com o objetivo de avaliar computacionalmente a funcionalidade de proteínas variantes a partir das seqüências de aminoácidos buscando reduzir o custo e o tempo desprendido em laboratório, este trabalho propõe o uso de técnicas de computação inteligentes (evolução in silicio), baseadas em aprendizado de máquina e computação evolutiva. Para o emprego de técnicas de AM, bancos de dados com elevado número de informações são fundamentais. Neste sentido, escolheu-se investigar as moléculas mutantes de hemoglobina, uma vez que a quantidade de informações disponíveis sobre a mesma é bastante extensa na literatura. Os resultados obtidos mostram que é possível desenvolver algoritmos eficientes para determinar a funcionalidade de variantes de hemoglobina. Com esses resultados, busca-se contribuir no desenvolvimento de técnicas de evolução dirigida com suporte computacional / In vitro evolution is a laboratorial method developed to molecule evolution mainly proteins. By producing mutations, this method looks for new molecule properties, aiming achieve new proteins for the development of drugs for diseases. The great challenge of in vitro evolution is the development of the highest possible number of molecules that reaches desired properties. This objective is a great challenge to be transposed, since only one infinitesimal fraction of generated proteins using DNA sequencies is usefull to obtain molecules with the desired function. Besides high financial support and time are required to apply this technique. With the objective of evaluating computacionaly and functionality of proteins mutants starting from aminoacids sequences looking for to reduce the cost and the time loosened at laboratory, this work proposes the use of intelligent computation techniques based on learning of it conspires and evolutionary computation. On the other hand, when machine learning techniques are used, it is fundamental to access data mining with high number of information. In order to reduce these difficulties, this work proposes a machine learning (ML) based on approach to evaluate computationaly hemoglobin variants. ML techniques require, in general, large data base. In order to supply this requirement, hemoglobin variants were used because there is a large number of hemoglobin variants available in the literature. The obtained results shown that is possible to develop efficient algorithms to determine hemoglobin variant function. These results can contribute for development of molecule evolution techniques
144

Characterization of the gut microbiota in diabetes mellitus II patients with adequate and inadequate metabolic control

Hamasaki-Matos, Angie Joyce, Cóndor-Marín, Katherine Marlene, Aquino-Ortega, Ronald, Carrillo-Ng, Hugo, Ugarte-Gil, Cesar, Silva-Caso, Wilmer, Aguilar-Luis, Miguel Angel, del Valle-Mendoza, Juana 01 December 2021 (has links)
El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / Objective: The objective of this study was to characterize the composition of the gut microbiota in type 2 Diabetes Mellitus (T2DM) patients with adequate and inadequate metabolic control, and its relationship with fiber consumption. Results: A total of 26 patients with type 2 diabetes mellitus (T2DM) were enrolled, of which 7 (26.9%) cases had adequate metabolic control (HbA1c < 7%) and 19 (73.1%) inadequate metabolic control (HbA1c ≥ 7%). It was observed that among patients with controlled T2DM, 2 (28.6%) cases presented good intake of fiber and 5 (71.4%) cases a regular intake. In contrast, in patients with uncontrolled T2DM, 13 (68.4%) patients reported a regular intake and 6 (31.6%) a poor intake. In relation to the identification of the gut microbiota, both groups presented a similar characterization. There were differences in the population of bacteria identified in both groups, however, the results were not statistically significant. The most frequently identified bacteria in controlled and uncontrolled T2DM patients were Prevotella (71.4% vs 52.6%), followed by Firmicutes (71.4% vs 42.1%), Proteobacteria (71.4% vs 36.8%) and Bacteroidetes (57.1% vs 37.8%). On the other hand, Fusobacterium, Actinobacteria were not identified in either of the two groups of study. / Revisión por pares
145

Hematologic and Vitamin Status of African American Women and Their Relationships to Pregnancy Outcome

Knight, Enid M., Spurlock, Bernice G., Johnson, Allan A., Oyemade, U. Jean, Cole, O. Jackson, West, William L., Manning, Malcolm G., Nolan, George, Bonds, Duane, Laryea, Haziel, Jones, Sidney, Westhey, Lennox, Edwards, Cecile H. 01 January 1991 (has links)
A prospective observational study was conducted to investigate the effects of nutrition and related factors on the outcome of pregnancy in nulliparous African American women 16-35 years of age. Blood samples from a subset of these subjects were taken during the first (1st), second (2nd) and third (3rd) trimesters of pregnancy and at delivery. Cord blood samples were also collected at delivery. Levels of selected biochemical variables including serum ferritin, vitamin B12 and folate as well as whole blood folate, and selected hematologic indices were determined and correlated with pregnancy outcome variables. During the second trimester of pregnancy, values for hematocrit and hemoglobin were less than 30% and 11 g/dL, respectively, in 16% and 30% of the participants, respectively. Serum and whole blood (WB) folate increased sequentially during pregnancy. Cord concentrations of serum folate were significantly higher than maternal concentrations at delivery (P<0.05). Serum ferritin declined significantly from 36±5.6 ng/ml in the first trimester to 17±1.5 ng/ml during the 3rd trimester (P<0.05), and returned to the 2nd trimester level (26±2.0 ng/ml) at delivery. Second trimester WB folate was positively related to birth weight (R2=0.21), while gestational age was inversely correlated with 3rd trimester vitamin B12 (R2=0.34). These data suggest that vitamin B12 and folate play an important role in the outcome of pregnancy in this population.
146

Reactions of Nitrite With Hemoglobin Measured by Membrane Inlet Mass Spectrometry

Tu, Chingkuang, Mikulski, Rose, Swenson, Erik R., Silverman, David N. 01 January 2009 (has links)
Membrane inlet mass spectrometry was used to observe nitric oxide in the well-studied reaction of nitrite with hemoglobin. The membrane inlet was submerged in the reaction solutions and measured NO in solution via its flux across a semipermeable membrane leading to the mass spectrometer detecting the mass-to-charge ratio m/z 30. This method measures NO directly in solution and is an alternate approach compared with methods that purge solutions to measure NO. Addition to deoxy-Hb(FeII) (near 38 μM heme concentration) of nitrite in a range of 80 μM to16 mM showed no accumulation of either NO or N2O3 on a physiologically relevant time scale with a sensitivity near 1 nM. The addition of nitrite to oxy-Hb(FeII) and met-Hb(FeIII) did not accumulate free NO to appreciable extents. These observations show that for several minutes after mixing nitrite with hemoglogin, free NO does not accumulate to levels exceeding the equilibrium level of NO. The presence of cyanide ions did not alter the appearance of the data; however, the presence of 2 mM mercuric ions at the beginning of the experiment with deoxy-Hb(FeII) shortened the initial phase of NO accumulation and increased the maximal level of free, unbound NO by about twofold. These experiments appear consistent with no role of met-Hb(FeIII) in the generation of NO and an increase in nitrite reductase activity caused by the presumed binding of mercuric to cysteine residues. These results raise questions about the ability of reduction of nitrite mediated by deoxy-Hb(FeII) to play a role in vasodilation.
147

The Effect of BI-Level Positive Airway Pressure on Postoperative Pulmonary Function Following Gastric Surgery for Obesity

Ebeo, C. T., Benotti, P. N., Byrd, R. P., Elmaghraby, Z., Lui, J. 01 January 2002 (has links)
The severely obese patient has varying degrees of intrinsic reduction of expiratory flow rates and lung volumes. Thus, the severely obese patient is predisposed to postoperative atelectasis, ineffective clearing of respiratory secretions, and other pulmonary complications. This study evaluated the effect of bi-level positive airway pressure (Bi-PAP) on pulmonary function in obese patients following open gastric bypass surgery. Patients with a body mass index (BMI) of at least 40 kg/m2 who were undergoing elective gastric bypass were eligible to be randomized to receive either BiPAP during the first 24 h postoperatively or conventional postoperative care. Patients with significant cardiovascular and pulmonary diseases were excluded from the study. Forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1.0), peak expiratory flow rate (PEFR), and percent hemoglobin oxygen saturation (SpO2) were measured preoperatively, and on postoperative days 1, 2, and 3. Twenty-seven patients were entered in the study, 14 received BiPAP and 13 received conventional postoperative care. There was no significant difference preoperatively between the study and control groups in regards to age, BMI, FVC, FEV1.0, PEFR or SpO2. Postoperatively, expiratory flow was decreased in both groups. However, the FVC and FEV1.0 were significantly higher on each of the three consecutive postoperative days in the patients who received BiPAP therapy. The SpO2 was significantly decreased in the control group over the same time period. Prophylactic BiPAP during the first 12--24 h postoperatively resulted in significantly higher measures of pulmonary function in severely obese patients who had undergone elective gastric bypass surgery. These improved measures of pulmonary function, however, did not translate into fewer hospital days or a lower complication rate in our study population of other wise healthy obese patients. Further study is necessary to determine if BiPAP therapy in the first 24 postoperative hours would be of benefit in severely obese patients with comorbid illnesses who have undergone elective gastric bypass.
148

The effects of elevated hemoglobin A1C on cognitive function in elderly type II diabetics in the Look Ahead study

Goldring, Anne E. 22 January 2016 (has links)
OBJECTIVE: Prolonged elevation of blood glucose levels in Type 2 Diabetes is related to a host of medical complications, most of which are mediated by micro and macro vascular damage. Importantly, diabetes is associated with accelerated cognitive decline and compromised brain health as the cerebral vasculature undergoes negative changes stemming from hyperglycemia. It is hypothesized that participants in the Look Ahead Brain study with higher HbA1c levels will exhibit worse performance on the cognitive measures, specifically on tasks assessing executive function. METHODS: Data on participants from the Look Ahead study who also participated in the Look Ahead Brain ancillary study (n = 113) were analyzed. This included HbA1c levels at year 10 (the year that participants were administered the cognitive assessment), mean HbA1c, and change in HbA1c from baseline to year. In order to assess executive function the results on two cognitive tests, the Modified Stroop Color and Word Test and the Trail Making Test, were analyzed. Then, relationships between HbA1c and performance on each of these cognitive tasks were analyzed using two approaches. First, the cohort was split into two group based on HbA1c (HbA1c ≤ 7% vs HbA1c > 7%). The latter of the two groups represented participants will poorer glycemic control. Second, linear correlations were assessed using the full range of HbA1c values as a continuous variable. RESULTS: There were no significant differences between HbA1c groups and performance on either of the cognitive tests. Interestingly, although not statistically significant, those with higher HbA1c levels performed slightly better on cognitive tasks. Correlation analyses revealed further trends in the direction opposite than expected, such that higher HbA1c levels were associated with better scores on both tests. CONCLUSION: The surprising results of this study are evidence of the fact that a great deal has yet to be learned about the effects of T2DM and cognitive decline. There are many potential future directions for the Look Ahead Brain data, and further analyses might provide clarifications to the results of this study.
149

A Patient-Centered Approach to Diabetes Education in a Rural Clinic

Okpuzor, Paul 01 January 2018 (has links)
Type 2 diabetes mellitus (T2DM) is a heterogeneous metabolic disease impacting more than 8.3% of adults in the United States. Diabetes-related care accounts for more than 11% of all patient care expenditures. The purpose of this project was to identify the primary concerns of members of the T2DM patient population in an underserved clinic in rural southcentral United States and to make recommendations for a staff diabetes education program to address these concerns. Orem's theory of self care outlined the importance of educating and supporting patients in their efforts to manage their own healthcare. Knowles's assumptions of how adult's learn guided the design and provided guidelines for the planning and implementation of the education program. The practice-focused question explored the major concerns of T2DM patients receiving care at the primary care clinic. Clinic providers completed the Diabetic Care Concern Assessment (DCCA) with all adult patients (n = 45) diagnosed with T2DM during primary care patient visits. DCCA responses were placed on an excel spreadsheet and analyzed for themes. Major themes from qualitative analysis of participant responses included fear of the disease, managing daily diabetes control, having additional education on diabetes, learning more about control strategies for diabetes, and helping with daily diabetes management. Findings will promote positive social change at the clinic as providers target specific concerns of their individual patients. T2DM patients may experience improved quality of life as they become empowered to manage their disease. The education program will also lead to the development and implementation of patient treatment plans that potentially decrease complications associated with diabetes.
150

Cause and Prevention of Liver Off-Flavor in Five Beef Chuck Muscles

Wadhwani, Ranjeeta 01 December 2008 (has links)
Liver off-flavor is a sporadic problem that limits the consumer acceptance of several beef chuck muscles, including the infraspinatus (flat iron steak). Residual blood hemoglobin is known to contribute to liver off-flavor development. This study was conducted to evaluate factors affecting development of liver off-flavor after cooking of beef chuck (shoulder) muscles. The study was conducted in three parts. The objective of part 1 was to determine effects of muscle (infraspinatus, longissimus dorsi, serratus ventralis, supraspinatus, teres major) and processing (with or w/o carcass electrical stimulation) on residual blood hemoglobin content and total pigment content of raw muscle and sensory characteristics after cooking to 71 or 82?C. The objective of part 2 was to evaluate the effect of antioxidant treatment and anaerobic packaging to possibly reduce the incidence of liver and other off-flavors of beef infraspinatus (IF) steaks. The objective of part 3 was to determine the effect of animal age (commercial grade; >42 months, compared to select grade; <30>months), antioxidant treatment, and anaerobic packaging on sensory characteristics of beef IF steaks. Among beef chuck muscles, the infraspinatus had highest mean liver flavor score of 2.08±1.00 where 2=slightly intense liver flavor. Other muscles (longissimus dorsi, serratus ventralis, supraspinatus, teres major) had mean liver flavor scores less than 2. Liver flavor score, myoglobin, hemoglobin, and total pigment content were higher (p<0.05) for infraspinatus muscle from older animals. Among select grade muscles, carcass electrical stimulation had no significant effect on liver flavor score. Rancid flavor scores were significantly increased from 1.34±0.65 to 1.58±0.84 as internal cook temperature increased from 71 to 82°C but mean TBA values as a measure of rancidity (0.25±0.15 and 0.29±0.13, respectively) were not affected by cook temperature. Antioxidant treatment significantly reduced TBA values, rancid, and liver flavor scores for aerobically packaged steaks (PVC or 80% O2-MAP) but had little effect on scores of steaks in anaerobic packaging (0.4% CO-MAP). Results of this study indicate that infraspinatus steaks from older animals are most likely to have objectionable liver, sour/grassy, or rancid flavors. Objectionable flavor scores were lower in steaks receiving antioxidant injection or packaged anaerobically in 0.4% CO-MAP.

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