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1.
J Sci Food Agric ; 103(15): 7664-7672, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37458104

RESUMEN

BACKGROUND: Nitrogen fertiliser is the major input and cost for wheat production, being required to support the development of the canopy to maximise yield and for the synthesis of the gluten proteins that are necessary for breadmaking. Consequently, current high-yielding cultivars require the use of nitrogen fertilisation levels above the yield optimum to achieve the grain protein content needed for breadmaking. This study aimed to reduce this requirement by identifying traits that allow the use of lower levels of nitrogen fertiliser to produce wheat for breadmaking. RESULTS: A range of commercial wheat genotypes (cultivars) were grown in multiple field trials (six sites over 3 years) in the UK with optimal (200 kg Ha-1 ) and suboptimal (150 kg Ha-1 ) application of nitrogen. Bulked grain samples from four sites per year were milled and white flours were baked using three types of breadmaking process. This identified five cultivars that consistently exhibited good breadmaking quality when grown with the lower nitrogen application. Chemical and biochemical analyses showed that the five cultivars were characterised by exhibiting grain protein deviation (GPD) and high dough elasticity. CONCLUSIONS: It is possible to develop novel types of wheat that exhibit good breadmaking quality by selecting for GPD and high dough strength. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Asunto(s)
Proteínas de Granos , Triticum/química , Nitrógeno/metabolismo , Fertilizantes , Pan/análisis , Fertilización
2.
Pain Pract ; 23(7): 847-850, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37074774

RESUMEN

BACKGROUND: Intrathecal baclofen (ITB) is a proven, effective treatment for refractory spasticity and chronic pain, with applications ranging from spinal cord injury to amyotrophic lateralsclerosis (ALS). Despite its effectiveness, the withdrawal syndrome of intrathecal baclofen can be life-threatening. CASE REPORT: This case describes the treatment of a patient with chronic spasticity related to ALS with an ITB pump infection requiring explant and a prolonged period of antibiotics before reimplantation. A 62-year-old man with ALS-related spasticity maintained on high-dose ITB for 20 years presented to the emergency department with one week of fever, confusion, and localized erythema to the R-side of his abdomen. Laboratories indicated a mild leukocytosis 12.9 K/uL and imaging showed a 2.9-cm fluid collection with fat stranding surrounding the ITB pump. The pack was explanted, and the patient started on intravenous antibiotics. Due to the high baclofen dosage, our pain service recommended PO (per os) baclofen 30 mg every 6 h via gastrostomy and PO diazepam 10 mg every 6 h via gastrostomy. These doses were titrated carefully to avoid oversedation while preventing withdrawal symptoms. On Day 23 postexplant, the patient had the baclofen pump reimplanted and baclofen titrated over three days to his previous dose of ITB. CONCLUSION: This case demonstrates a successful approach to avoiding severe baclofen withdrawal using PO baclofen combined with PO diazepam. The high dose of maintenance ITB (1188.8 mcg/day), the inability to reinsert the patient's intrathecal pump, and the high risk of intubation in a patient with severe neuromuscular dysfunction all made this a challenging case.


Asunto(s)
Esclerosis Amiotrófica Lateral , Dolor Crónico , Relajantes Musculares Centrales , Síndrome de Abstinencia a Sustancias , Masculino , Humanos , Persona de Mediana Edad , Baclofeno/uso terapéutico , Relajantes Musculares Centrales/uso terapéutico , Esclerosis Amiotrófica Lateral/complicaciones , Esclerosis Amiotrófica Lateral/tratamiento farmacológico , Bombas de Infusión Implantables/efectos adversos , Espasticidad Muscular/tratamiento farmacológico , Espasticidad Muscular/etiología , Diazepam/uso terapéutico , Dolor Crónico/tratamiento farmacológico , Inyecciones Espinales
3.
Am J Clin Nutr ; 111(2): 406-419, 2020 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-31851298

RESUMEN

BACKGROUND: Alaska Native (AN) people have the world's highest recorded incidence of sporadic colorectal cancer (CRC) (∼91:100,000), whereas rural African (RA) people have the lowest risk (<5:100,000). Previous data supported the hypothesis that diet affected CRC risk through its effects on the colonic microbiota that produce tumor-suppressive or -promoting metabolites. OBJECTIVES: We investigated whether differences in these metabolites may contribute to the high risk of CRC in AN people. METHODS: A cross-sectional observational study assessed dietary intake from 32 AN and 21 RA healthy middle-aged volunteers before screening colonoscopy. Analysis of fecal microbiota composition by 16S ribosomal RNA gene sequencing and fecal/urinary metabolites by 1H-NMR spectroscopy was complemented with targeted quantification of fecal SCFAs, bile acids, and functional microbial genes. RESULTS: Adenomatous polyps were detected in 16 of 32 AN participants, but not found in RA participants. The AN diet contained higher proportions of fat and animal protein and less fiber. AN fecal microbiota showed a compositional predominance of Blautia and Lachnoclostridium, higher microbial capacity for bile acid conversion, and low abundance of some species involved in saccharolytic fermentation (e.g., Prevotellaceae, Ruminococcaceae), but no significant lack of butyrogenic bacteria. Significantly lower concentrations of tumor-suppressive butyrate (22.5 ± 3.1 compared with 47.2 ± 7.3 SEM µmol/g) coincided with significantly higher concentrations of tumor-promoting deoxycholic acid (26.7 ± 4.2 compared with 11 ± 1.9 µmol/g) in AN fecal samples. AN participants had lower quantities of fecal/urinary metabolites than RA participants and metabolite profiles correlated with the abundance of distinct microbial genera in feces. The main microbial and metabolic CRC-associated markers were not significantly altered in AN participants with adenomatous polyps. CONCLUSIONS: The low-fiber, high-fat diet of AN people and exposure to carcinogens derived from diet or environment are associated with a tumor-promoting colonic milieu as reflected by the high rates of adenomatous polyps in AN participants.


Asunto(s)
Bacterias/metabolismo , Población Negra , Neoplasias Colorrectales/microbiología , Microbioma Gastrointestinal/fisiología , Adulto , Bacterias/clasificación , Estudios de Cohortes , Neoplasias Colorrectales/epidemiología , Neoplasias Colorrectales/genética , Estudios Transversales , Dieta , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , ARN Bacteriano/genética , ARN Ribosómico 16S/genética , Población Rural
4.
Neuropsychopharmacology ; 43(3): 598-606, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28948978

RESUMEN

In recent years, the boundaries of psychopathology as defined by diagnostic categories have been criticized as inadequately 'carving nature at its joints' with respect to the neurobiology of major mental disorders. In 2010 the NIMH launched the Research Domain Criteria (RDoC) framework for understanding mental illnesses as brain circuit disorders that extend beyond DSM-defined diagnoses. In the present study we focus on cognitive dysfunction, a core feature of schizophrenia (SZ) and bipolar disorder (BPD), and use functional magnetic resonance imaging (fMRI) during a cognitive control (CC) task in recent onset patients to test the hypothesis that at a behavioral and underlying neural circuitry level these deficits exist on a continuum (as opposed to showing categorical differences) across the two disorders. In total, 53 healthy controls, 24 recent (<1 y) onset patients with BPD Type I with psychotic features, and 70 recent onset patients with SZ performed the AX-Continuous Performance Task while undergoing event-related fMRI at 1.5 T. In addition to behavior task-associated response was examined in frontoparietal regions-of-interest. In an a priori contrast-based analysis, significant deficits across patient groups (vs controls) were observed on CC-associated performance as well as frontoparietal response. These analyses further revealed a continuum of deficits in which BPD showed intermediate levels of CC relative to controls and SZ. Poor CC was associated with poverty and disorganization symptoms across patient groups. These results support the hypothesis that CC dysfunction in BPD and SZ reflects a continuum of deficits that cuts across traditional, DSM-based classification. Implications for the neurobiology of these diseases are discussed.


Asunto(s)
Trastorno Bipolar/fisiopatología , Encéfalo/fisiopatología , Disfunción Cognitiva/fisiopatología , Trastornos Psicóticos/fisiopatología , Esquizofrenia/fisiopatología , Adolescente , Adulto , Trastorno Bipolar/diagnóstico por imagen , Trastorno Bipolar/psicología , Encéfalo/diagnóstico por imagen , Mapeo Encefálico , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/etiología , Función Ejecutiva/fisiología , Femenino , Humanos , Estudios Longitudinales , Imagen por Resonancia Magnética , Masculino , Pruebas Neuropsicológicas , Trastornos Psicóticos/diagnóstico por imagen , Trastornos Psicóticos/psicología , Esquizofrenia/diagnóstico por imagen , Psicología del Esquizofrénico , Adulto Joven
5.
J Comput Assist Tomogr ; 39(6): 945-50, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26418539

RESUMEN

OBJECTIVE: Superolateral Hoffa's fat pad (SHFP) edema is a previously described magnetic resonance (MR) finding located between the patellar tendon and the lateral femoral condyle. The purpose of our study was to determine the prevalence and clinical significance of SHFP edema in female collegiate volleyball players. MATERIALS AND METHODS: Sixteen female collegiate volleyball players were consented for bilateral knee evaluations which consisted of history, physical examination and MR imaging. Each MR study was reviewed for the presence of SHFP edema, and 6 patellar maltracking measurements were done. These were tibial tuberosity-trochlear groove distance, patellar translation, lateral patellofemoral angle, trochlear depth, trochlear sulcus angle, and lateral trochlear inclination angle. RESULTS: A total of 16 athletes, 32 knees (16 girls; age range, 18-22 years; mean, 19.9) were enrolled in the study. Sixteen knees (50%) in 8 athletes had SHFP edema, with 100% bilaterality; 16 knees in 8 athletes had no evidence of SHFP edema (50%). Functional outcomes and physical examination findings were within normal limits for all athletes with no difference noted between SHFP edema-positive and -negative individuals. There was a statistically significant difference in the tibial tuberosity-trochlear groove distance, patellar translation, and patellofemoral angle (P value of < 0.001, 0.03 and 0.01, respectively) between the SHFP edema-positive and -negative individuals. CONCLUSIONS: Elite female volleyball athletes have a very high prevalence of SHFP edema, which is always bilateral. Although the exact etiology of SHFP edema remains inconclusive, it could potentially be a sensitive indicator of subtle patellar maltracking which cannot be distinguished by history and physical examination findings. Given the very high prevalence of SHFP edema and this being an asymptomatic finding, there is likely little clinical significance of this in majority of high-performance athletes.


Asunto(s)
Tejido Adiposo/patología , Atletas , Edema/patología , Articulación de la Rodilla/patología , Voleibol , Adolescente , Adulto , Femenino , Fémur , Humanos , Imagen por Resonancia Magnética , Rótula , Estudios Prospectivos , Adulto Joven
6.
Nat Commun ; 6: 6342, 2015 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-25919227

RESUMEN

Rates of colon cancer are much higher in African Americans (65:100,000) than in rural South Africans (<5:100,000). The higher rates are associated with higher animal protein and fat, and lower fibre consumption, higher colonic secondary bile acids, lower colonic short-chain fatty acid quantities and higher mucosal proliferative biomarkers of cancer risk in otherwise healthy middle-aged volunteers. Here we investigate further the role of fat and fibre in this association. We performed 2-week food exchanges in subjects from the same populations, where African Americans were fed a high-fibre, low-fat African-style diet and rural Africans a high-fat, low-fibre western-style diet, under close supervision. In comparison with their usual diets, the food changes resulted in remarkable reciprocal changes in mucosal biomarkers of cancer risk and in aspects of the microbiota and metabolome known to affect cancer risk, best illustrated by increased saccharolytic fermentation and butyrogenesis, and suppressed secondary bile acid synthesis in the African Americans.


Asunto(s)
Colon/microbiología , Neoplasias del Colon/etiología , Dieta Alta en Grasa/efectos adversos , Fibras de la Dieta/estadística & datos numéricos , Mucosa Intestinal , Negro o Afroamericano/estadística & datos numéricos , Anciano , Biomarcadores/metabolismo , Colon/metabolismo , Dieta con Restricción de Grasas , Dieta Alta en Grasa/estadística & datos numéricos , Heces/química , Voluntarios Sanos , Humanos , Inflamación/etiología , Inflamación/metabolismo , Metaboloma , Microbiota , Persona de Mediana Edad , Población Rural/estadística & datos numéricos , Sudáfrica , Orina/química
7.
J Comput Assist Tomogr ; 39(1): 57-63, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25319603

RESUMEN

OBJECTIVE: We have encountered unexplained anteromedial tibial rim edema in acute anterior cruciate ligament (ACL) tears. Our goal was to determine the incidence, internal derangements, and mechanism of injury in patients with anteromedial tibial rim edema (rim sign). MATERIALS AND METHODS: A retrospective review of ACL tears diagnosed by magnetic resonance imaging over 7 years was performed. Patients were dichotomized into those with and without a rim sign. RESULTS: There were 132 acute ACL tears. Individuals with a rim sign (31, 23%) had more contusions, fractures, ligament tears (P < 0.001), posterolateral corner injuries (P = 0.001), and posterior horn lateral meniscus tears (P = 0.042) than those without. Five individuals demonstrated edema in the inferior patella, consistent with patellotibial impaction. CONCLUSIONS: The rim sign is common in ACL tears, indicating greater internal derangement. The rim sign represents patellotibial impaction with edema rarely present in the patella.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Ligamento Cruzado Anterior/patología , Contusiones/patología , Imagen por Resonancia Magnética/métodos , Rótula/lesiones , Rótula/patología , Tibia/lesiones , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Tibia/patología , Adulto Joven
8.
Arch Pathol Lab Med ; 138(4): 543-5, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23937608

RESUMEN

CONTEXT: Lung cancer is the leading cause of cancer deaths worldwide. First-generation tyrosine kinase inhibitors improve progression-free survival in lung cancers with epidermal growth factor receptor (EGFR) mutations. EGFR mutations occur predominantly in exons 19 and 21 in lung adenocarcinomas of Asians (∼30%), whites (∼15%), and African Americans (∼19%). However, minimal information exists on the prevalence or type of genetic changes that occur in lung cancers in US Hispanic patients. We investigated the EGFR mutation frequency in primary lung adenocarcinomas in US Hispanics compared with non-Hispanic whites. OBJECTIVE: To evaluate EGFR mutations in lung adenocarcinomas from US Hispanic patients compared with those from non-Hispanic white patients. DESIGN: DNA samples were extracted from paraffin-embedded tissue of consecutive lung adenocarcinomas from 83 patients. Samples were collected from 40 Hispanics and 43 non-Hispanic whites. Mutations in EGFR were analyzed using a custom assay. Results.-Fourteen of 83 patients (16.9%) had EGFR mutations in their tumor DNA, including 6 of 40 Hispanics (15.0%) and 8 of 43 non-Hispanic whites (18.6%). No association with age, sex, or tumor stage was identified. Smoking history could not be obtained for most of the 83 patients, although 8 of the 11 patients with EGFR mutations for whom smoking history was obtained were nonsmokers. Most of the tumors with EGFR mutations (12 of 14; 85.7%) were acinar with lepidic or papillary subtypes. EGFR mutations occurred in exon 19 (42.8%), exon 18 (28.6%), exon 20 (28.6%), and exon 21 (14.3%). Two cases had 2 mutations identified in different exons. CONCLUSION: The frequency of EGFR mutations is similar in US Hispanics compared with non-Hispanic whites.


Asunto(s)
Adenocarcinoma/genética , Receptores ErbB/genética , Neoplasias Pulmonares/genética , Mutación , Adenocarcinoma/patología , Adenocarcinoma del Pulmón , Adulto , Anciano , Anciano de 80 o más Años , Exones , Femenino , Frecuencia de los Genes , Hispánicos o Latinos/genética , Humanos , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Eliminación de Secuencia , Estados Unidos , Población Blanca/genética
9.
Am J Clin Nutr ; 98(1): 111-20, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23719549

RESUMEN

BACKGROUND: Epidemiologic studies have suggested that most cases of sporadic colon cancer can be attributed to diet. The recognition that colonic microbiota have a major influence on colonic health suggests that they might mediate colonic carcinogenesis. OBJECTIVE: To examine the hypothesis that the influence of diet on colon cancer risk is mediated by the microbiota through their metabolites, we measured differences in colonic microbes and their metabolites in African Americans with a high risk and in rural native Africans with a low risk of colon cancer. DESIGN: Fresh fecal samples were collected from 12 healthy African Americans aged 50-65 y and from 12 age- and sex-matched native Africans. Microbiomes were analyzed with 16S ribosomal RNA gene pyrosequencing together with quantitative polymerase chain reaction of the major fermentative, butyrate-producing, and bile acid-deconjugating bacteria. Fecal short-chain fatty acids were measured by gas chromatography and bile acids by liquid chromatography-mass spectrometry. RESULTS: Microbial composition was fundamentally different, with a predominance of Prevotella in native Africans (enterotype 2) and of Bacteroides in African Americans (enterotype 1). Total bacteria and major butyrate-producing groups were significantly more abundant in fecal samples from native Africans. Microbial genes encoding for secondary bile acid production were more abundant in African Americans, whereas those encoding for methanogenesis and hydrogen sulfide production were higher in native Africans. Fecal secondary bile acid concentrations were higher in African Americans, whereas short-chain fatty acids were higher in native Africans. CONCLUSION: Our results support the hypothesis that colon cancer risk is influenced by the balance between microbial production of health-promoting metabolites such as butyrate and potentially carcinogenic metabolites such as secondary bile acids.


Asunto(s)
Colon/microbiología , Neoplasias del Colon/microbiología , Dieta , Metagenoma , Negro o Afroamericano , Anciano , Ácidos y Sales Biliares/análisis , Ácidos y Sales Biliares/metabolismo , Población Negra , Butiratos/análisis , Butiratos/metabolismo , Carcinógenos/análisis , Carcinógenos/metabolismo , Cromatografía de Gases , Cromatografía Liquida , Colon/metabolismo , ADN Bacteriano/aislamiento & purificación , Ácidos Grasos Volátiles/análisis , Heces/química , Heces/microbiología , Femenino , Humanos , Masculino , Espectrometría de Masas , Persona de Mediana Edad , ARN Ribosómico 16S/aislamiento & purificación , Reacción en Cadena en Tiempo Real de la Polimerasa , Factores de Riesgo , Población Rural
10.
J Struct Biol ; 170(1): 32-40, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20102741

RESUMEN

Cholesterol oxidase is of significant commercial interest as it is widely used as a biosensor for the detection of cholesterol in clinical samples, blood serum and food. Increased stability of this enzyme with regards to temperature and different solvent conditions are of great importance to the reliability and versatility of its applications. We here report the crystal structure of the cholesterol oxidase of Chromobacterium sp. DS-1 (CHOLOX). In contrast to other previously characterized cholesterol oxidases, this enzyme retains high activity in organic solvents and detergents at temperatures above 85 degrees C despite its mesophilic origin. With the availability of one other homologous oxidase of known three-dimensional structure, a detailed comparison of its sequence and structure was performed to elucidate the mechanisms of stabilization. In contrast to factors that typically contribute to the stability of thermophilic proteins, the structure of CHOLOX exhibits a larger overall cavity volume, less charged residues and less salt bridge interactions. Moreover, the vast majority of residue substitutions were found on or near the protein's solvent exposed surface. We propose that the engineering of enhanced stability may also be accomplished through selective engineering of the protein periphery rather than by redesigning its entire core.


Asunto(s)
Colesterol Oxidasa/química , Chromobacterium/enzimología , Modelos Moleculares , Conformación Proteica , Aminoácidos/genética , Cristalización , Escherichia coli
11.
Artículo en Inglés | MEDLINE | ID: mdl-19194002

RESUMEN

The ethanolamine ammonia-lyase microcompartment is composed of five different shell proteins that have been proposed to assemble into symmetrically shaped polyhedral particles of varying sizes. Here, preliminary X-ray analysis of crystals of the bacterial microcompartment shell protein Eut-L from Escherichia coli is reported. Cloning, overexpression and purification resulted in highly pure protein that crystallized readily under many different conditions. In all cases the protein forms thin hexagonal plate-shaped crystals belonging to space group P3 that are of unusually high stability against different solvent conditions. The crystals diffracted to a resolution of 2.0 A using synchrotron radiation but proved to be radiation-sensitive. Preparations of heavy-atom-derivatized crystals for use in determining the three-dimensional structure are under way.


Asunto(s)
Proteínas de Escherichia coli/química , Etanolamina Amoníaco-Liasa/química , Poliproteínas/química , Cristalografía por Rayos X , Escherichia coli/enzimología , Escherichia coli/crecimiento & desarrollo , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Etanolamina/química , Etanolamina/metabolismo , Etanolamina Amoníaco-Liasa/metabolismo , Poliproteínas/genética , Poliproteínas/metabolismo
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