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1.
Pediatr Crit Care Med ; 24(9): 760-766, 2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-37171215

RESUMEN

OBJECTIVES: To compare the relative associations of lactate, albumin, and the lactate-albumin ratio (LAR) measured early in disease course against mortality and prevalence of multiple organ dysfunction syndrome (MODS) in a general sample of critically ill pediatric patients. DESIGN: Retrospective analysis of the Health Facts (Cerner Corporation, Kansas City, MO) national database. SETTING: U.S. hospitals with PICUs. PATIENTS: Children admitted to the ICU ( n = 648) from 2009 to 2018 who had lactate and albumin measured within 6 hours of admission. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: A total of 648 admissions were included, with an overall mortality rate of 10.8% ( n = 70) and a MODS prevalence of 29.3% ( n = 190). Compared with survivors, deaths had higher initial lactates (7.3 mmol/L [2.6-11.7 mmol/L] vs 1.9 mmol/L [1.2-3.1 mmol/L]; p < 0.01), lower initial albumins (3.3 g/dL [2.7-3.8 g/dL] vs 4.2 g/dL [3.7-4.7 g/dL]; p < 0.01), and higher LARs (2.2 [1.0-4.2] vs 0.5 [0.3-0.8]; p < 0.01), with similar trends in patients with MODS versus those without MODS. LAR demonstrated a higher odds ratio (OR) for death than initial lactate alone (2.34 [1.93-2.85] vs 1.29 [1.22-1.38]) and a higher OR for MODS than initial lactate alone (2.10 [1.73-2.56] vs 1.22 [1.16-1.29]). Area under the receiver operating characteristic (AUROC) curve of LAR for mortality was greater than initial lactate (0.86 vs 0.82; p < 0.01). The LAR AUROC for MODS was greater than the lactate AUROC (0.71 vs 0.66; p < 0.01). Trends of lactate, albumin, and LAR for mortality were consistent across several diagnostic subgroups (trauma, primary respiratory failure, toxicology), but not all. CONCLUSIONS: LAR measured early in the course of critical illness is significantly associated with mortality and development of MODS when compared with initial lactate or initial albumin alone in critically ill pediatric patients.


Asunto(s)
Ácido Láctico , Insuficiencia Multiorgánica , Humanos , Niño , Estudios Retrospectivos , Insuficiencia Multiorgánica/epidemiología , Enfermedad Crítica , Albúminas , Unidades de Cuidado Intensivo Pediátrico , Pronóstico
2.
J Oral Maxillofac Surg ; 80(9): 1557-1563, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35594907

RESUMEN

PURPOSE: Oral and maxillofacial surgeons frequently encounter patients who require extractions following exposure to head and neck radiation, and they must assess the risk of extraction and consider alternatives such as deliberate root retention. The purpose of this study was to determine whether dose volume would be a better predictor for osteoradionecrosis (ORN) than total dose. METHODS: This is a retrospective cohort study of patients diagnosed with ORN following head and neck radiation (administered between January 2006 and December 2018) and a comparison group selected based on site and dosage who did not develop ORN. The predictor variables were total radiation dose and mandibular dose volume, and the outcome variable was ORN occurrence. Covariates included age, sex, cancer stage and site, radiation therapy type, smoking status, alcohol use, adjuvant chemotherapy use, medical comorbidities, and concomitant tumor surgery. Logistic regression models were employed and area under receiver operating characteristic curve (AUROC) and model accuracy (Acc) were used to determine the better predictor. RESULTS: A total of 56 patients were included in the study: 27 ORN positive (ORN+) and 29 matched controls who did not develop ORN (ORN-). Most patients were male (76.8%), considered smokers (78.6%), used alcohol (80.4%), were in stage IV (66.1%), received chemotherapy (75.0%), and received intensity modulated radiation therapy radiation (55.4%). The statistical models with V50 Gy (cc) and V65 Gy (cc) dosage variables exhibited greater predictability of ORN occurrence than total dose (AUROC: 0.90 vs 0.76 and model accuracy: 0.82 vs 0.75, respectively). CONCLUSIONS: The results suggest that following head and neck radiation, dose volume may be a better predictor of ORN risk than total dose. This finding is significant, both for the oral and maxillofacial surgeon who is preoperatively assessing ORN risk following radiation exposure, and for the radiation oncologist striving to minimize the risk associated with their treatment.


Asunto(s)
Neoplasias de Cabeza y Cuello , Enfermedades Mandibulares , Osteorradionecrosis , Radioterapia de Intensidad Modulada , Femenino , Neoplasias de Cabeza y Cuello/radioterapia , Humanos , Masculino , Enfermedades Mandibulares/cirugía , Osteorradionecrosis/etiología , Osteorradionecrosis/cirugía , Dosificación Radioterapéutica , Radioterapia de Intensidad Modulada/efectos adversos , Estudios Retrospectivos
3.
Headache ; 60(10): 2357-2363, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33128398

RESUMEN

BACKGROUND: OnabotulinumtoxinA (BTX) has become a mainstream treatment for chronic migraine (CM). Patients often have varied expectations for treatment success but little is known about how these initial impressions influence continuation of therapy. OBJECTIVE: To record expectations of benefit and procedural discomfort (PD) from initial BTX treatment and to investigate their association with treatment success, defined as continuation of treatment for >3 sessions within a 2-year period. METHODS: A retrospective chart review of CM patients receiving initial treatment with BTX was performed. Patients were questioned about their expectations of benefit and PD as rated on a 0-10 scale. Responses were then compared with continuation of therapy beyond 3 sessions to identify the presence of significant association. RESULTS: Responses from patients (N = 297) were analyzed. About 173 subjects continued with BTX therapy for more than 3 sessions (173/297, 58.3%). Unadjusted odds ratios (OR) for expectation of benefit (EOB) (OR 1.11, 95% CI 0.99-1.24, P = .087) and PD (OR 1.02, 95% CI 0.90-1.16, P = .780) were not significantly predictive of continuing treatment. After considering sex, age, year of treatment, and previous headache preventative trials, only female sex (OR 2.02, 95% CI 1.09-3.74, P = .025) was found to be significantly associated with treatment continuation. CONCLUSIONS: In the usual care setting, PD and EOB are not significantly associated with therapy continuation in patients receiving initial treatment with BTX for the prevention of CM. However, after considering sex, age, year of treatment, and number of previous headache preventives attempted, we found that female patients had twice the likelihood of continuing with BTX therapy compared to male patients with CM.


Asunto(s)
Toxinas Botulínicas Tipo A/uso terapéutico , Trastornos Migrañosos/prevención & control , Fármacos Neuromusculares/uso terapéutico , Dolor Asociado a Procedimientos Médicos , Aceptación de la Atención de Salud , Satisfacción del Paciente , Adulto , Toxinas Botulínicas Tipo A/efectos adversos , Enfermedad Crónica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fármacos Neuromusculares/efectos adversos , Estudios Retrospectivos , Factores Sexuales
4.
Am J Transplant ; 18(7): 1690-1698, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29333639

RESUMEN

The Kidney Allocation System (KAS) was implemented in December 2014 with unknown impact on the pediatric waitlist. To understand the effect of KAS on pediatric registrants, deceased donor kidney transplant (DDKT) rate was assessed using interrupted time series analysis and time-to-event analysis. Two allocation eras were defined with an intermediary washout period: Era 1 (01/01/2013-09/01/2014), Era 2 (09/01/2014-03/01/2015), and Era 3(03/01/2015-03/01/2017). When using Cox proportional hazards, there was no significant association between allocation era and DDKT likelihood as compared to Era 1 (Era 3: aHR: 1.07, 95% CI: 0.97-1.18, P = .17). However, this was not consistent across all subgroups. Specifically, while highly sensitized pediatric registrants were consistently less likely to be transplanted than their less sensitized counterparts, this disparity was attenuated in Era 3 (Era 1 aHR: 0.04, 95%CI: 0.01-0.14, P < .001; Era 3 aHR: 0.33, 95% CI: 0.21-0.53, P < .001) whereas the youngest registrants aged 0-6 experienced a 21% decrease in DDKT likelihood in Era 3 as compared to Era 1 (aHR: 0.79, 95% CI: 0.64-0.98, P = .03). Thus, while overall DDKT likelihood remained stable with the introduction of KAS, registrants ≤ 6 years of age were disadvantaged, warranting further study to ensure equitable access to transplantation.


Asunto(s)
Rechazo de Injerto/mortalidad , Asignación de Recursos para la Atención de Salud/organización & administración , Trasplante de Riñón/estadística & datos numéricos , Asignación de Recursos/normas , Donantes de Tejidos/provisión & distribución , Obtención de Tejidos y Órganos/estadística & datos numéricos , Listas de Espera/mortalidad , Adolescente , Niño , Preescolar , Muerte , Selección de Donante , Femenino , Estudios de Seguimiento , Rechazo de Injerto/etiología , Supervivencia de Injerto , Prueba de Histocompatibilidad , Humanos , Lactante , Recién Nacido , Trasplante de Riñón/efectos adversos , Trasplante de Riñón/mortalidad , Masculino , Pronóstico , Factores de Riesgo , Tasa de Supervivencia , Obtención de Tejidos y Órganos/organización & administración , Receptores de Trasplantes
5.
Ann Clin Microbiol Antimicrob ; 16(1): 19, 2017 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-28356113

RESUMEN

Serratia marcescens is a Gram-negative bacterium with proven resistance to multiple antibiotics and causative of catheter-associated infections. Bacterial colonization of catheters mainly involves the formation of biofilm. The objectives of this study were to explore the susceptibility of S. marcescens biofilms to high doses of common antibiotics and non-antimicrobial agents. Biofilms formed by a clinical isolate of S. marcescens were treated with ceftriaxone, kanamycin, gentamicin, and chloramphenicol at doses corresponding to 10, 100 and 1000 times their planktonic minimum inhibitory concentration. In addition, biofilms were also treated with chemical compounds such as polysorbate-80 and ursolic acid. S. marcescens demonstrated susceptibility to ceftriaxone, kanamycin, gentamicin, and chloramphenicol in its planktonic form, however, only chloramphenicol reduced both biofilm biomass and biofilm viability. Polysorbate-80 and ursolic acid had minimal to no effect on either planktonic and biofilm grown S. marcescens. Our results suggest that supratherapeutic doses of chloramphenicol can be used effectively against established S. marcescens biofilms.


Asunto(s)
Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Cloranfenicol/farmacología , Viabilidad Microbiana/efectos de los fármacos , Serratia marcescens/efectos de los fármacos , Serratia marcescens/fisiología , Biomasa , Humanos , Polisorbatos/farmacología , Triterpenos/farmacología , Ácido Ursólico
6.
J Res Natl Inst Stand Technol ; 121: 464-475, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-34434635

RESUMEN

This article introduces in archival form the Nanolithography Toolbox, a platform-independent software package for scripted lithography pattern layout generation. The Center for Nanoscale Science and Technology (CNST) at the National Institute of Standards and Technology (NIST) developed the Nanolithography Toolbox to help users of the CNST NanoFab design devices with complex curves and aggressive critical dimensions. Using parameterized shapes as building blocks, the Nanolithography Toolbox allows users to rapidly design and layout nanoscale devices of arbitrary complexity through scripting and programming. The Toolbox offers many parameterized shapes, including structure libraries for micro- and nanoelectromechanical systems (MEMS and NEMS) and nanophotonic devices. Furthermore, the Toolbox allows users to precisely define the number of vertices for each shape or create vectorized shapes using Bezier curves. Parameterized control allows users to design smooth curves with complex shapes. The Toolbox is applicable to a broad range of design tasks in the fabrication of microscale and nanoscale devices.

7.
J Surg Res ; 189(2): 326-34, 2014 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-24694717

RESUMEN

BACKGROUND: This study reports on the development of a novel method for achieving ex vivo reanimation of hearts from a porcine donation after circulatory death (DCD) model without the use of donor pretreatment. METHODS: Porcine hearts (n = 23) were procured 10-29 min after confirmation of asystole. All hearts underwent initial flush with AQIX RS-I solution (London, UK). A 2-h preservation period followed: group 1 hearts (n1-n11) were preserved using static cold storage, group 2 hearts (n12-n17) were preserved using oxygenated, hypothermic machine perfusion (MP), and group 3 hearts (n18-n23) were subjected to retrograde oxygen persufflation. Reperfusion was performed on a Langendorff modification of a Model 33 Functional Circulation circuit. In hearts n16-n23, a dialysis circuit was incorporated into the circuit to facilitate removal of metabolites. The experimental protocol was allowed to follow an evolutionary course, with the aim of achieving greater success with reanimation. RESULTS: In group 1 (static cold storage), 7 of the 11 hearts (63.6%) achieved reanimation on the ex vivo circuit. Two of the six hearts (33.3%) in group 2 (MP) were successfully reanimated. All the six hearts (100%) in group 3 (persufflation) were successfully reanimated. The period of sustained reanimation increased when dialysis was incorporated into the circuit with a maximum of 300 min. CONCLUSIONS: Porcine DCD hearts after 29 min of warm ischemia can be reanimated using the method described. A mechanism of reoxygenation (oxygenated MP or coronary sinus oxygen persufflation) during preservation appears mandatory for hearts from DCDs. Persufflation was associated with a higher probability of successful reanimation. Dialysis in the warm phase was useful in removing metabolites that could interfere with reanimation. The results demonstrate the potential of DCDs to counter the decline affecting heart transplantation.


Asunto(s)
Muerte , Trasplante de Corazón , Recolección de Tejidos y Órganos/métodos , Animales , Técnicas In Vitro , Reperfusión Miocárdica , Porcinos
8.
J Aging Phys Act ; 22(1): 96-102, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23416307

RESUMEN

The understanding of prefrail and nonfrail older adults' postural control with and without increased environmental and cognitive stress is imperative to the development of targeted interventions to decrease fall risk within these populations. Thirty-eight individuals participated in this study. Postural control testing included the Sensory Organization Test (SOT) on a NeuroCom EquiTest. Cognitive and environmental load testing was performed during Condition 6 of the SOT. Though there were no group differences on composite equilibrium score (p = .06), the cognitive task (Stroop task) impaired equilibrium scores more than the auditory or visual distracter tasks (p < .05 and p < .01) for both groups. These results suggest that both prefrail and nonfrail older adults' postural control is reduced in demanding environments. Given these findings, the need for multimodal exercise interventions to target both physical and cognitive factors is apparent.


Asunto(s)
Accidentes por Caídas/prevención & control , Envejecimiento , Cognición , Ambiente , Equilibrio Postural , Trastornos de la Sensación/diagnóstico , Factores de Edad , Anciano , Anciano de 80 o más Años , Envejecimiento/fisiología , Envejecimiento/psicología , Diagnóstico por Computador/métodos , Terapia por Ejercicio/métodos , Terapia por Ejercicio/psicología , Femenino , Evaluación Geriátrica/métodos , Humanos , Vida Independiente , Pruebas de Inteligencia , Masculino , Persona de Mediana Edad , Evaluación de Necesidades , Evaluación de Resultado en la Atención de Salud , Desempeño Psicomotor , Medición de Riesgo
9.
J Gastrointest Oncol ; 15(1): 485-490, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38482231

RESUMEN

Background: Cholangiocarcinoma (CCA) is a rare and aggressive gastrointestinal cancer. Unfortunately, 60% to 70% of early-stage CCA patients experience disease recurrence after curative resection and standard adjuvant therapy. Currently, there is no reliable tool to identify CCA recurrence before radiographic detection. Longitudinal monitoring of circulating tumor DNA (ctDNA) has shown promising value in molecular identification of relapse prior to conventional surveillance in other solid tumors. However, there is a scarcity of data on ctDNA in CCA after curative surgery. Case Description: An 81-year-old male with stage 3A intrahepatic CCA achieved radiographic remission after curative resection and was started on standard adjuvant capecitabine on post-operative day (POD) 50. Tumor-informed ctDNA tested positive on two consecutive occasions, with the titer increasing from 0.16 mean tumor molecule (MTM)/mL on POD 92 to 0.80 MTM/mL on POD 183, despite being on capecitabine. carbohydrate antigen 19-9 (CA19-9) also continued to increase from 175.6 U/mL on POD 92 to 7,594.9 U/mL on POD 217. Notably, surveillance computed tomography (CT) scans showed no evidence of disease (NED) on POD 126, 186, and 211. Molecular profiling and next-generation sequencing (NGS) panels from CCA tissue revealed microsatellite instability-high (MSI-H). After extensive discussions with the patient regarding the rising ctDNA titer despite being on capecitabine for nearly 6 months, we initiated pembrolizumab on POD 224 prior to radiographic recurrence. Given the tumor is MSI-H, and the preferred toxicity profile compared to the front-line chemotherapy option for CCA, we started pembrolizumab. ctDNA became undetectable, and CA19-9 returned to the reference range with pembrolizumab. As of the last follow-up on POD 876, the patient has continued pembrolizumab without noticeable side effects, and imaging continues to show NED, with persistent negative ctDNA and normal CA19-9 levels. Conclusions: This case demonstrates the potential utility of tumor-informed ctDNA in CCA as (I) an early detection tool before radiographic recurrence; (II) a response monitoring tool as a surrogate biomarker that can guide therapy optimization; and (III) shows that early intervention with immunotherapy or potentially targeted agents based on ctDNA may lead to improved survival outcomes.

10.
J Surg Res ; 183(2): e39-48, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23647801

RESUMEN

BACKGROUND: Deceased cardiac donors (DCDs) have become a useful source of organs for liver transplantation; nevertheless, there are concerns about the longevity of these grafts. The aim of this study was to evaluate the use of extracorporeal membrane oxygenation (ECMO) to resuscitate DCD porcine livers as a preclinical model using hepatocyte isolation and viability as a marker to assess whole-graft preservation. MATERIALS AND METHODS: We randomized Landrace pigs into three groups after cardiac death and 30 min of warm ischemia: group 1, peritoneal cooling with intravascular cooling for 2 h; group 2, ECMO for 2 h; and group 3, control (conventional intravascular cooling and retrieval). We then reperfused group 1 and 2 livers for 2 h on an ex vivo reperfusion circuit and isolated hepatocytes. RESULTS: After reperfusion, hepatocyte viability was significantly improved in the ECMO group compared to the cooling groups, as measured by trypan blue, methylthiazolyldiphenyl-tetrazolium bromide, and seeding efficiency. Glycogen and reduced glutathione content were significantly used in the ECMO group both before and after reperfusion compared with group 2. The adenosine diphosphate:adenosine triphosphate ratio showed an improved trend (lower) in the ECMO group compared with the cooling group but did not reach statistical significance either before or after reperfusion. CONCLUSIONS: This preclinical study suggests that ECMO is a viable technique for liver preservation that gives an improved yield of hepatocytes when isolated from a DCD liver, suggesting improved liver preservation.


Asunto(s)
Muerte , Oxigenación por Membrana Extracorpórea/métodos , Hepatocitos/fisiología , Trasplante de Hígado/métodos , Hígado/fisiología , Resucitación/métodos , Donantes de Tejidos , Animales , Separación Celular , Supervivencia Celular/fisiología , Femenino , Hepatocitos/citología , Hígado/citología , Modelos Animales , Porcinos
11.
Neurol Clin Pract ; 12(2): e4-e6, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35747887

RESUMEN

Background and Objectives: We present the case of a 67-year-old man who developed encephalopathy, headaches, and seizure activity after initiating treatment with the novel tyrosine kinase inhibitor, sitravatinib. Methods: The patient was identified in routine clinical practice. Results: Brain MRI revealed lobar microhemorrhages and bihemispheric vasogenic edema. The patient met the criteria for probable cerebral amyloid angiopathy-related inflammation (CAA-ri) and responded favorably to high-dose methylprednisolone. Discussion: This report of neurologic autoimmunity in a patient receiving sitravatinib opens new lines of inquiry into the pathophysiology of CAA-ri. We emphasize the importance of early recognition and treatment of CAA-ri among patients receiving immunomodulatory chemotherapy.

12.
BMJ Case Rep ; 14(5)2021 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-33990297

RESUMEN

Malignant lesions of the vermiform appendix make up a rare subset of colorectal cancer. While colorectal cancer frequently metastasises to the liver, lung, regional lymph nodes and peritoneum, metastasis to the breast is extremely rare. Here, we describe the case of an 84-year-old woman who had the incidental finding of appendiceal adenocarcinoma following emergency laparoscopic appendectomy. She declined further operative or adjuvant treatment for her disease. She represented 1 year later with metastatic appendiceal adenocarcinoma disease to her left breast. A simple mastectomy for symptomatic treatment was performed. In this report, we describe the first case of appendiceal adenocarcinoma metastases to the breast. Due to its rarity, there is a paucity of evidence related to the management of this condition. The limited evidence is reviewed and discussed.


Asunto(s)
Adenocarcinoma , Neoplasias del Apéndice , Neoplasias de la Mama , Adenocarcinoma/cirugía , Anciano de 80 o más Años , Apendicectomía , Neoplasias del Apéndice/cirugía , Femenino , Humanos , Mastectomía
13.
Isotopes Environ Health Stud ; 57(5): 492-515, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34269607

RESUMEN

The Upper Cibolo Creek (UCC) karst watershed in Central Texas, USA, represents a portion of the drainage area that supplies water to the recharge zone for the Edwards Aquifer. However, the surface water-groundwater interactions along the UCC are not well quantified, and the hydraulic interactions are important for water budget and water quality of the aquifer. In this study, we investigated the evolution of hydrochemical and isotopic signatures (δ18O, δ2H and d-excess) from precipitation, surface water to groundwater in the UCC watershed from 2017 to 2019, and investigated surface water-groundwater interactions using samples from 14 creeks/spring sites. Factor analysis for the observed parameters demonstrates that changes in water hydrochemistry are primarily controlled by human activity, precipitation input, and water-rock interaction. Hierarchical clustering analysis of temporal isotope variations confirms that significant surface water-groundwater interactions occur in the UCC watershed. We identified relationships between nitrate concentrations at creek/spring sites and land-use conditions, and nitrate input sources were determined utilizing the dual-isotope analyses (δ15N and δ18O) of nitrate. This study provides capacity for a more precise assessment of water resources and water quality in Central Texas.


Asunto(s)
Agua Subterránea , Contaminantes Químicos del Agua , Monitoreo del Ambiente , Humanos , Texas , Contaminantes Químicos del Agua/análisis , Calidad del Agua
15.
Foods ; 9(8)2020 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-32752174

RESUMEN

Beer flavor and sensory quality are affected by storage time and temperature due to chemical breakdown and aging. This study aimed to investigate the organoleptic properties of temperature-abused, unpasteurized craft beer and analyze the chemical breakdown associated with the process. Sensory tests were performed using a triangle test to determine consumer identification of temperature-abused beer. The chemical tests were conducted to determine the chemical breakdown of the two beer groups: control beer (COB) and temperature-abused beer (TAB). The chemical analysis of the two beer groups showed significant changes in multiple chemical compounds such as ethyl esters, linear aldehydes, and sulphur-compounds; however, the sensory analysis results were not significant even though 39% of participants were able to detect differences. in this study, two factors identified that caused chemical reactions in the TABs were oxidation and live yeast cells. In conclusion, these results can be used by beer producers to ensure a quality product throughout the distribution chain by controlling time and temperature.

16.
Enzyme Microb Technol ; 134: 109476, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32044023

RESUMEN

Soybean is a most promising sustainable protein source for feed and food to help meet the protein demand of the rapidly rising global population. To enrich soy protein, the environment-friendly enzymatic processing requires multiple carbohydrases including cellulase, xylanase, pectinase, α-galactosidase and sucrase. Besides enriched protein, the processing adds value by generating monosaccharides that are ready feedstock for biofuel/bioproducts. Aspergillus could produce the required carbohydrases, but with deficient pectinase and α-galactosidase. Here we address this critical technological gap by focused evaluation of the suboptimal productivity of pectinase and α-galactosidase. A carbohydrases-productive strain A. niger (NRRL 322) was used with soybean hull as inducing substrate. Temperatures at 20 °C, 25 °C and 30 °C were found to affect cell growth on sucrose with an Arrhenius-law activation energy of 28.7 kcal/mol. The 30 °C promoted the fastest cell growth (doubling time = 2.1 h) and earliest enzyme production, but it gave lower final enzyme yield due to earlier carbon-source exhaustion. The 25 °C gave the highest enzyme yield. pH conditions also strongly affected enzyme production. Fermentations made with initial pH of 6 or 7 were most productive, e.g., giving 1.9- to 2.3-fold higher pectinase and 2.2- to 2.3-fold higher α-galactosidase after 72 h, compared to the fermentation with a constant pH 4. Further, pH must be kept above 2.6 to avoid limitation in pectinase production and, in the later substrate-limiting stage, kept below 5.5 to avoid pectinase degradation. α-Galactosidase production always followed the pectinase production with a 16-24 h lag; presumably, the former relied on pectin hydrolysis for inducers generation. Optimal enzyme production requires controlling the transient availability of inducers.


Asunto(s)
Aspergillus niger/enzimología , Poligalacturonasa/biosíntesis , Proteínas de Soja/metabolismo , alfa-Galactosidasa/biosíntesis , Biocombustibles , Fermentación , Hidrólisis , Glycine max , Temperatura
17.
Infect Immun ; 77(12): 5300-10, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19805527

RESUMEN

Pseudomonas aeruginosa is a leading cause of pneumonia, and many components of the innate immune system have been proposed to exert important effects in preventing lung infection. However, a vigorous experimental system to identify an overriding, key effector mediating innate immunity to lung infection has not been utilized. As many of the important components of innate immunity are involved in recruitment and activation of polymorphonuclear neutrophils (PMNs) to infected tissues, we hypothesized that the cells and factors needed for their proper recruitment to the lung comprised the major mediators of innate immunity. In neutropenic mice, intranasal (i.n.) doses of P. aeruginosa as low as 10 to 100 CFU/mouse produced a fatal lung infection, compared with 10(7) to >10(8) CFU for nonneutropenic mice. There was only a very modest increased mortality in mice lacking mature lymphocytes and no increased mortality in mice depleted of alveolar macrophages when administered i.n. P. aeruginosa. Recombinant mouse granulocyte colony-stimulating factor increased survival of neutropenic mice after i.n. P. aeruginosa inoculation. MyD88(-/-) mice, which cannot recruit PMNs to the lungs, were highly susceptible to fatal P. aeruginosa lung infection, with bacterial doses of <120 CFU being lethal. Activation of a MyD88-independent pathway for PMN recruitment to the lungs in MyD88(-/-) mice resulted in enhanced protection against P. aeruginosa lung infection. Overall, in the absence of PMNs, mice cannot resist P. aeruginosa lung infection from extremely small bacterial doses. There is an inescapable requirement for local PMN recruitment and activation to mediate innate immunity to P. aeruginosa lung infection.


Asunto(s)
Inmunidad Innata , Neutrófilos/inmunología , Neumonía Bacteriana/inmunología , Neumonía Bacteriana/microbiología , Infecciones por Pseudomonas/inmunología , Pseudomonas aeruginosa/inmunología , Animales , Susceptibilidad a Enfermedades , Femenino , Pulmón/inmunología , Pulmón/patología , Linfocitos/inmunología , Macrófagos Alveolares/inmunología , Ratones , Ratones Endogámicos C3H , Ratones Endogámicos C57BL , Ratones Noqueados , Infecciones por Pseudomonas/microbiología , Análisis de Supervivencia
18.
Gait Posture ; 28(1): 58-61, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18023185

RESUMEN

Individuals with vision loss are at an increased risk of falls. Understanding what factors contribute to postural instability within this population is a necessary step towards the development of physiotherapeutic programs targeted at reduction of falls within this population. Forty-six age-matched participants were evaluated with the sensory organization test (SOT) on a NeuroCom Equitest. The conditions provided accurate and inaccurate sensory information to test the participants' ability to utilize the correct information to maintain postural stability. A one-way analysis of variance was performed on composite balance scores between groups. Based on the data analysis, significant differences were apparent in equilibrium composite scores (P<.05) and strategy utilized to maintain postural stability between the visually impaired and sighted sample. Results indicate that restricted vision has a negative impact on overall postural stability and visually impaired individuals utilize greater use of hip strategy to maintain postural stability.


Asunto(s)
Ceguera/fisiopatología , Equilibrio Postural/fisiología , Adulto , Humanos , Persona de Mediana Edad , Personas con Daño Visual
20.
Percept Mot Skills ; 103(1): 231-7, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17037666

RESUMEN

For many populations the ability to move efficiently is compromised by an impaired muscular functioning. Strength development is necessary to overcome the effects of gravity to maintain posture and generate movement responses for mobility. The strength and power capabilities of individuals with total blindness (n = 12) were compared to those with partial vision (n = 12) to evaluate effects of vision on performance. Results indicate that (1) no significant differences were apparent between total blindness and partial vision, (2) significant sex differences were evident in each group, and (3) better performance was apparent at lower velocities. It was concluded that physical performance in individuals with blindness and partial vision are equally deficient.


Asunto(s)
Ceguera , Ejercicio Físico , Fuerza Muscular/fisiología , Aptitud Física , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dinamómetro de Fuerza Muscular , Índice de Severidad de la Enfermedad , Torque
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