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1.
Phys Chem Chem Phys ; 25(21): 14992-14999, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37211874

RESUMO

Magnetic antiperovskites, having chiral noncollinear antiferromagnetic ordering, have shown remarkable properties that range from negative thermal expansion to anomalous Hall effects. Nevertheless, details on the electronic structure, related to the oxidation states and the octahedral center's site effects, are still scarce. Here, we show a theoretical study, based on first-principles calculations in the framework of density-functional theory (DFT), on the electronic properties associated with the nitrogen site effects on the structural, electronic, magnetic, and topological degrees of freedom. Thus, we show that the nitrogen vacancy increases the value of the anomalous Hall conductivity and retains the chiral Γ4g antiferromagnetic ordering. Moreover, we reveal, based on the Bader charges and the electronic structure analysis, the negative and positive oxidation states of the Ni- and Mn-sites, respectively. This is in agreement with the expected A3α+Bß-Xδ- oxidation states to satisfy charge neutrality in antiperovskites, but the negative charge is rare for transition metals. Finally, we extrapolate our findings on the oxidation states to several Mn3BN compounds, showing that the antiperovskite structure is an ideal platform to encounter negative oxidation states for metals sitting at the corner B-sites.

2.
Phys Rev Lett ; 121(11): 117601, 2018 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-30265112

RESUMO

Herewith, first-principles calculations based on density functional theory are used to describe the ideal magnetization reversal through polarization switching in BaCuF_{4} which, according to our results, could be accomplished close to room temperature. We also show that this ideal coupling is driven by a single soft mode that combines both polarization, and octahedral rotation. The later being directly coupled to the weak ferromagnetism of BaCuF_{4}. This, added to its strong Jahn-Teller distortion and its orbital ordering, makes this material a very appealing prototype for crystals in the ABX_{4} family for multifunctional applications. The described mechanism behaves ideally as it couples the ferroelectric and the magnetic properties naturally and it has not been reported previously.

3.
Pharmacogenomics J ; 14(3): 223-8, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24018621

RESUMO

Using a derivation cohort (N=349), we developed the first warfarin dosing algorithm that includes recently discovered polymorphisms in VKORC1 and CYP2C9 associated with warfarin dose requirement in African Americans (AAs). We tested our novel algorithm in an independent cohort of 129 AAs and compared the dose prediction to the International Warfarin Pharmacogenetics Consortium (IWPC) dosing algorithms. Our algorithm explains more of the phenotypic variation (R(2)=0.27) than the IWPC pharmacogenomics (R(2)=0.15) or clinical (R(2)=0.16) algorithms. Among high-dose patients, our algorithm predicted a higher proportion of patients within 20% of stable warfarin dose (45% vs 29% and 2% in the IWPC pharmacogenomics and clinical algorithms, respectively). In contrast to our novel algorithm, a significant inverse correlation between predicted dose and percent West African ancestry was observed for the IWPC pharmacogenomics algorithm among patients requiring ⩾60 mg per week (ß=-2.04, P=0.02).


Assuntos
Anticoagulantes/uso terapêutico , Farmacogenética , Varfarina/uso terapêutico , Anticoagulantes/farmacocinética , Estudos de Coortes , Citocromo P-450 CYP2C9/genética , Feminino , Humanos , Masculino , Vitamina K Epóxido Redutases/genética , Varfarina/farmacocinética
4.
J Digit Imaging ; 27(3): 351-68, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24197278

RESUMO

We present a novel algorithm for the extraction of cavity features on images of human vessels. Fat deposits in the inner wall of such structure introduce artifacts, and regions in the images captured invalidating the usual assumption of an elliptical model which makes the process of extracting the central passage effectively more difficult. Our approach was designed to cope with these challenges and extract the required image features in a fully automated, accurate, and efficient way using two stages: the first allows to determine a bounding segmentation mask to prevent major leakages from pixels of the cavity area by using a circular region fill that operates as a paint brush followed by Principal Component Analysis with auto correction; the second allows to extract a precise cavity enclosure using a micro-dilation filter and an edge-walking scheme. The accuracy of the algorithm has been tested using 30 computed tomography angiography scans of the lower part of the body containing different degrees of inner wall distortion. The results were compared to manual annotations from a specialist resulting in sensitivity around 98 %, false positive rate around 8 %, and positive predictive value around 93 %. The average execution time was 24 and 18 ms on two types of commodity hardware over sections of 15 cm of length (approx. 1 ms per contour) which makes it more than suitable for use in interactive software applications. Reproducibility tests were also carried out with synthetic images showing no variation for the computed diameters against the theoretical measure.


Assuntos
Angiografia/métodos , Interpretação de Imagem Assistida por Computador/métodos , Reconhecimento Automatizado de Padrão/métodos , Radiografia Intervencionista/métodos , Algoritmos , Artefatos , Humanos , Intensificação de Imagem Radiográfica , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Software , Tomografia Computadorizada por Raios X/métodos
5.
Meat Sci ; 205: 109297, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37544261

RESUMO

This study evaluated the effects of a constant current electrical stimulation (CCES) system and hormonal growth-promoting (HGP) implants on the quality and palatability of the longissimus thoracis et lumborum (LTL) from yearling-finished steers. The experiment used a total of 46 Angus cross steers, which were either non-implanted (n = 20) or implanted with trenbolone acetate and estradiol benzoate (n = 26). The CCES was applied to one side of each carcass during the slaughter process, whereas the other side remained unstimulated. Regardless of the application of HGP implants, the CCES reduced pH at 3 and 72 h post-mortem and shear force at all ageing times (P < 0.05), improved colour at 72 h post-mortem and during the retail display (P < 0.05), increased initial and overall tenderness (P < 0.01), and decreased the amount of perceived connective tissue and the proportion of trained panelists detecting spongy texture (P < 0.05) compared to meat from unstimulated carcass sides. Although CCES increased meat purge losses and reduced moisture content (P < 0.05), this did not affect meat juiciness (P > 0.10). CCES interacted with HGP to prevent increase in drip loss (P > 0.10), increase frequency of panelists detecting bloody/serumy flavour and typical texture, and reduce the proportion of panelists detecting rubbery texture in meat (P < 0.05). Regardless of stimulation treatment, meat from implanted animals had a more pronounced pH decline at 72 h post-mortem (P < 0.05) and a higher proportion of panelists finding no off-flavours (P < 0.05) or bloody/serumy flavour (P < 0.01) than non-implanted cattle. The CCES system tested in this study improved LTL quality and palatability of heavier beef carcasses.


Assuntos
Anabolizantes , Músculo Esquelético , Bovinos , Animais , Músculo Esquelético/fisiologia , Carne , Acetato de Trembolona/farmacologia , Anabolizantes/farmacologia , Estimulação Elétrica
6.
Meat Sci ; 202: 109219, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37172551

RESUMO

This study evaluated the effects of in-the-bag dry-ageing (BDA) (21 and 42 d) on meat quality, palatability, and volatile compounds of clod heart, brisket, and flat iron cuts from steers. In all cuts, BDA increased moisture losses (P < 0.05), but this did not reduce the juiciness of 21 d BDA versus wet-aged (WA) steaks. In clod heart, BDA increased overall tenderness at 21 d compared to 21 d WA (P < 0.01). Regardless of ageing period, BDA of clod heart increased beef flavour and salty taste and decreased sour-dairy and stale/cardboard flavours and concentrations of volatile compounds derived from lipid oxidation compared to WA (P < 0.05). In brisket, BDA increased salty taste and fatty aroma and reduced bloody/serumy flavour, whereas decreased beef and buttery flavours and intensified some unpleasant aromas/flavours (P < 0.05) for both ageing periods. The BDA of flat iron increased several undesirable aromas/flavours and decreased sweet taste and beef and buttery flavours (P < 0.05), regardless of ageing period. Overall, BDA for 42 d decreased meat quality and palatability and increased concentrations of volatile compounds from lipid oxidation, especially in flat iron cuts. Value could be recovered by customizing BDA periods by cut.


Assuntos
Carne , Paladar , Animais , Bovinos , Carne/análise , Aromatizantes , Envelhecimento , Lipídeos
7.
Meat Sci ; 188: 108800, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35305444

RESUMO

This study evaluated the effects of in-the-bag dry-ageing on eating quality and volatile compounds of longissimus lumborum from cows and steers. Compared to wet-ageing, in-the-bag dry-ageing increased purge loss (P < 0.0001), cooking time (P < 0.0001), salty taste (P < 0.05) and sour-dairy flavour (P < 0.01), whereas decreased cooking loss (P < 0.0001), amount of perceptible connective tissue (P < 0.05) and livery flavour (P < 0.05) in both cow and steer meat. This dry-ageing technology also increased juiciness (P < 0.01) and brown-roasted aroma (P < 0.05) in steer meat, whereas decreased the juiciness (P < 0.01) of cow meat. Regardless of the ageing method, cow meat was tougher (P < 0.0001), less juicy (P < 0.001) and sweeter (P < 0.05) and presented higher amount of perceived connective tissue (P < 0.0001) than steer meat, whereas steer meat had higher ratings for beef (P < 0.05) and brown-roasted (P < 0.01) flavours. Volatile compounds were largely affected (P < 0.05) by animal-type, most of them being higher in cow than steer meat. In contrast, in-the-bag dry-ageing affected a few volatile compounds such as alcohols, aldehydes and ketones.


Assuntos
Manipulação de Alimentos , Músculo Esquelético , Animais , Bovinos , Culinária , Feminino , Manipulação de Alimentos/métodos , Carne/análise , Paladar
8.
J Cell Biol ; 40(2): 395-414, 1969 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-4178321

RESUMO

Two methods used for the electron microscopic detection of glycoproteins were applied to a variety of cell types in the rat; one involved successive treatment of sections with periodic acid, chromic acid, and silver methenamine; and the other, a brief treatment with a chromic acid-phosphotungstic acid mixture. The results obtained with the two methods were identical and, whenever the comparison was possible, similar to those obtained with the periodic acid-Schiff technique of light microscopy. In secretory as well as in nonsecretory cells, parts of the Golgi apparatus are stained. The last saccule on one side of each Golgi stack is strongly reactive (mature face), and the last saccule on the other side shows little or no reactivity (immature face); a gradient of reactivity occurs in between these saccules. The more likely explanation of the increase in staining intensity is that carbohydrate is synthesized and accumulates in saccules as they migrate toward the mature face. In many secretory cells, the mature face is associated with strongly stained secretory granules. Other structures stained are: (1) small vesicles, dense and multivesicular bodies, at least some of which are presumed to be lysosomal in nature; (2) cell coat; and (3) basement membrane. The evidence suggests that the Golgi saccules provide glycoproteins not only for secretion, but also for the needs of the lysosomal system as well as for incorporation into the cell coat and perhaps basement membrane.


Assuntos
Glicoproteínas/análise , Complexo de Golgi/análise , Coloração e Rotulagem , Animais , Células Sanguíneas/análise , Cromatos , Epididimo/análise , Epitélio/análise , Intestinos/análise , Rim/análise , Masculino , Métodos , Microscopia Eletrônica , Neurônios/análise , Pâncreas/análise , Ácido Periódico , Ácido Fosfotúngstico , Ratos , Retina/análise , Prata , Espermatozoides/análise
9.
J Immunoassay Immunochem ; 29(4): 370-89, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18821411

RESUMO

Methods of lymphocyte enrichment tend to vary across species, with the most common techniques employed being density-gradient separation and erythrocyte lysis buffer enrichment. In this study, we assessed lymphocyte viability and proliferation of avian, equine, and murine lymphocytes enriched by a commercial density-gradient technique and under identical, standardized culture conditions. The results of this study clearly show that, under identical enrichment and culture conditions, lymphocyte viability and function can be quite different among the equine, bird, and mouse species. Secondly, the type of enrichment technique employed in the mouse can impact the quality of the immune data generated.


Assuntos
Separação Celular/métodos , Linfócitos/citologia , Linfócitos/fisiologia , Animais , Apoptose , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular , Células Cultivadas , Galinhas , Concanavalina A/farmacologia , Feminino , Cavalos , Contagem de Linfócitos , Masculino , Camundongos
10.
J Thromb Haemost ; 15(4): 735-743, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28135054

RESUMO

Essentials Genetic variants controlling gene regulation have not been explored in pharmacogenomics. We tested liver expression quantitative trait loci for association with warfarin dose response. A novel predictor for increased warfarin dose response in African Americans was identified. Precision medicine must take into account population-specific variation in gene regulation. SUMMARY: Background Warfarin is commonly used to control and prevent thromboembolic disorders. However, because of warfarin's complex dose-requirement relationship, safe and effective use is challenging. Pharmacogenomics-guided warfarin dosing algorithms that include the well-established VKORC1 and CYP2C9 polymorphisms explain only a small proportion of inter-individual variability in African Americans (AAs). Objectives We aimed to assess whether transcriptomic analyses could be used to identify regulatory variants associated with warfarin dose response in AAs. Patients/Methods We identified a total of 56 expression quantitative trait loci (eQTLs) for CYP2C9, VKORC1 and CALU derived from human livers and evaluated their association with warfarin dose response in two independent AA warfarin patient cohorts. Results We found that rs4889606, a strong cis-eQTL for VKORC1 (log10 Bayes Factor = 12.02), is significantly associated with increased warfarin daily dose requirement (ß = 1.1; 95% confidence interval [CI] 0.46 to 1.8) in the discovery cohort (n = 305) and in the replication cohort (ß = 1.04; 95% CI 0.33 -1.7; n = 141) after conditioning on relevant covariates and the VKORC1 -1639G>A (rs9923231) variant. Inclusion of rs4889606 genotypes, along with CYP2C9 alleles, rs9923231 genotypes and clinical variables, explained 31% of the inter-patient variability in warfarin dose requirement. We demonstrate different linkage disequilibrium patterns in the region encompassing rs4889606 and rs9923231 between AAs and European Americans, which may explain the increased dose requirement found in AAs. Conclusion Our approach of interrogating eQTLs identified in liver has revealed a novel predictor of warfarin dose response in AAs. Our work highlights the utility of leveraging information from regulatory variants mapped in the liver to uncover novel variants associated with drug response and the importance of population-specific research.


Assuntos
Variação Genética , Tromboembolia/etnologia , Tromboembolia/genética , Varfarina/administração & dosagem , Adulto , Negro ou Afro-Americano , Idoso , Algoritmos , Proteínas de Ligação ao Cálcio/genética , Estudos de Coortes , Citocromo P-450 CYP2C9/genética , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Genótipo , Humanos , Desequilíbrio de Ligação , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Pessoa de Meia-Idade , Farmacogenética , Medicina de Precisão , Locos de Características Quantitativas , Tromboembolia/tratamento farmacológico , Vitamina K Epóxido Redutases/genética
11.
Obstet Gynecol ; 49(1 suppl): 59-63, 1977 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-831181

RESUMO

Three cases of mixed mesodermal sarcoma (MMS) are reported and a review of 90 cases from the English literature is presented. All cases were analyzed with regard to clinical features, prognosis, and therapeutic efficacy. The histogenesis of these rare tumors is discussed and a new classification of ovarian sarcomas is proposed. MMS usually afflicts the postmenopausal women and occurs more often in the nulliparous female. The disease is usually advanced (Stage III) when diagnosed and thus provides a difficult challenge to any postoperative therapy.


Assuntos
Mesenquimoma/patologia , Neoplasias Ovarianas/patologia , Sarcoma/patologia , Adolescente , Adulto , Fatores Etários , Idoso , Antineoplásicos/uso terapêutico , Feminino , Humanos , Mesenquimoma/mortalidade , Mesenquimoma/terapia , Pessoa de Meia-Idade , Paridade , Prognóstico , Grupos Raciais , Sarcoma/classificação
12.
Obstet Gynecol ; 56(2): 226-30, 1980 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6994003

RESUMO

Midline abdominal wound closure with the Smead-Jones technique was reviewed on an oncology service. No dehiscences were recorded for 747 patients. This result was compared with a lower-risk gynecologic service that used layered wound closures. The mass closure was superior in prevention of wound disruption.


Assuntos
Abdome/cirurgia , Deiscência da Ferida Operatória/prevenção & controle , Técnicas de Sutura , Adulto , California , Feminino , Humanos , Pessoa de Meia-Idade , Infecção da Ferida Cirúrgica/epidemiologia
13.
Alcohol ; 13(1): 75-8, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8837939

RESUMO

Nitrogen narcosis is often compared to alcohol intoxication, but no actual studies have been carried out in humans to test the comparability of these effects. If a common mechanism of action is responsible for the behavioral effects of these substances, biological variability of response to alcohol should correlate to that of nitrogen in the same individual. To test this hypothesis, subjective feelings were assessed in two separate occasions in 14 adult male, healthy volunteers, nonprofessional divers. In one occasion, each subject received 0.75 ml/kg (0.60 g/kg) alcohol 50% (v/v PO) and in another day underwent a simulated dive at 50 m for 30 min in a hyperbaric chamber. There was a significant correlation between reported feelings in the two sessions; subjects who felt less intoxicated after drinking also felt less nitrogen narcosis during the simulated dive. The results, although preliminary, raise the hypothesis that ethanol and nitrogen may share the same mechanisms of action in the brain and that biological differences might account for interindividual variability of responses to both ethanol and nitrogen.


Assuntos
Intoxicação Alcoólica/fisiopatologia , Narcose por Gás Inerte/fisiopatologia , Adulto , Pressão Atmosférica , Mergulho , Etanol/sangue , Etanol/farmacologia , Humanos , Masculino , Nitrogênio/farmacologia , Projetos Piloto
14.
J Am Podiatr Med Assoc ; 89(10): 534-9, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10546427

RESUMO

Complex regional pain syndrome is a chronic pain syndrome that is often instigated by postoperative or post-traumatic events. The disease process can progress through three stages, the first of which tends to respond best to treatment. A review of the literature is presented, followed by a report of a patient who developed symptoms of complex regional pain syndrome following a water-skiing accident.


Assuntos
Síndromes da Dor Regional Complexa/diagnóstico , Síndromes da Dor Regional Complexa/terapia , Traumatismos do Tornozelo/complicações , Traumatismos em Atletas/complicações , Síndromes da Dor Regional Complexa/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Entorses e Distensões/complicações
15.
J Am Podiatr Med Assoc ; 81(7): 366-72, 1991 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1941580

RESUMO

The evaluation and treatment of bursitis in the foot is a complex problem for the clinician. There is no one standard approach or set treatment for the patient who presents with pain suspected of being secondary to bursal involvement, primarily because there are myriad conditions and anatomical sites involved. Compounding this problem is the wide variation in the presence of these structures from patient to patient. Therefore, each distinct pathologic situation must be examined, diagnosed, and treated, based on its individual anatomical and etiologic factors. In the interest of completeness, the special anatomy of bursae and their specific pathologic conditions are reviewed.


Assuntos
Bursite , Doenças do Pé , Pé/anatomia & histologia , Tenossinovite , Bolsa Sinovial/anatomia & histologia , Bursite/etiologia , Bursite/fisiopatologia , Doenças do Pé/etiologia , Doenças do Pé/fisiopatologia , Humanos , Dor/etiologia , Membrana Sinovial/anatomia & histologia , Tendões/anatomia & histologia , Tenossinovite/etiologia , Tenossinovite/fisiopatologia , Dedos do Pé
16.
Clin Podiatr Med Surg ; 6(1): 197-208, 1989 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2653609

RESUMO

The Lapidus procedure for correction of hallux valgus has fallen into disfavor over the years because of its complexity and often poor results. This article re-examines the Lapidus and describes its indications and use. The authors contend that the procedure does have efficacy and a place in the foot surgeon's armamentarium.


Assuntos
Hallux Valgus/cirurgia , Artrodese , Humanos , Ossos do Metatarso/cirurgia , Osteotomia , Ossos do Tarso/cirurgia
17.
Acta Gastroenterol Latinoam ; 29(3): 95-9, 1999.
Artigo em Espanhol | MEDLINE | ID: mdl-10533654

RESUMO

Two patients with cancer of the right colon fistulized in duodenum underwent simultaneous right hemicolectomies and cephalic duodenopancreatectomies. There were no important post-operative complications and they are both alive eleven and ten years after surgery. In another case a piece of duodenum adherent to colon was resected and the duodenum was transversally sutured, segments IV and V of the liver were also resected because of a infiltration. The patient is well more than three years after surgery. Another similar patient who underwent resection of a part of the duodenum during a right hemicolectomy due to adenocarcinoma, developed the head of the pancreas ten months later which was resected by means of a cephalic duodenopancreatectomy. He survived the second operation for three years and a half and died with carcinomatosis. A fourth female patient who had been referred due to jaundice caused by cephalopancreatic cancer was reoperated two months later with resection of the tumor Seven months after duodenopancreatectomy she underwent another operation for resection of a bleeding cancer of the rectum by means of anterior resection. She survived for four and a half years. Cancers of body and tail of the pancreas sometimes invade the left colon and make necessary resection in the same operation. This happened in four other cases. In two of them it was necessary to resect stomach and the first jejunal loop. Respective survivals were of two years and nine months in two cases, others are 4111 alive more than two years after surgery. But the fourth case, who had an acinar carcinoma, died a month later with en hepatic metastasis which grew rapidly. The opposite happened to the tenth patient because colon cancer invaded pancreas and stomach, that were partially resected. The patient is alive two and a half years later.


Assuntos
Neoplasias do Colo/cirurgia , Neoplasias Duodenais/cirurgia , Neoplasias Primárias Múltiplas/cirurgia , Neoplasias Pancreáticas/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Colectomia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pancreaticoduodenectomia
18.
Rev. med. vet. zoot ; 66(1): 43-52, ene.-abr. 2019. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1014236

RESUMO

ABSTRACT The aim of this study was to classify and characterize the compositional quality of milk from river buffaloes (Bubalus bubalis) and cows (Bos spp.) in Colombia based on the fat, protein, and total solid (TS) contents. Using a hierarchical procedure, data on milk from river buffaloes (n = 7,726) and cows (n = 49,330) were filtered and subjected to cluster analysis in order to generate three groups: Normal (N), High quality (HQ) and Poor Quality (PQ). The categorized database was then randomly separated into two sets (training and validation) and a discriminant analysis was applied. In total, 37.3% of river buffalo milk samples were classified as N (6.80% fat, 4.34% protein, and 16.80% TS), 13% as HQ (9.41% fat, 4.93% protein, and 19.50% TS), and 43.7% as PQ (3.95% fat, 3.92% protein, and 13.7% TS). In contrast, 41.8% of cow milk samples were classified as N (3.64% fat, 3.37% protein, 12.42% TS), 41.2% as PQ (2.71% fat, 3.08% protein, and 10.6% TS), and 16.9% as HQ (5.46% fat, 4.01% protein, and 14.82% TS). The discriminant models for both river buffalo and cow milk were able to classify milk in the N and PQ groups with >90% accuracy, and that in the HQ group with >85% accuracy.


RESUMEN El objetivo de este estudio fue caracterizar y clasificar la calidad composicional de la leche de búfala (Bubalus bubalis) y de vaca (Bos spp.) en Colombia con base en los contenidos de grasa, proteína y sólidos totales. Mediante un procedimiento jerárquico los datos de leche de búfalos de agua (n = 7,726) y vacas (n = 49,330) se filtraron y se sometieron a análisis de conglomerados para generar tres grupos: Normal (N), Alta calidad (HQ) y Calidad deficiente (PQ). La base de datos categorizada se separó aleatoriamente en dos conjuntos (entrenamiento y validación) y se aplicó un análisis discriminante. En total, 37,3% de las muestras de leche de búfalo de agua se clasificaron como N (6,80% de grasa, 4,34% de proteína y 16,80% de TS); 13% como HQ (9,41% de grasa, 4,93% de proteína y 19,50% de TS) y 43,7 % como PQ (3,95% de grasa, 3,92% de proteína y 13,7% de TS). En contraste, el 41,8% de las muestras de leche de vaca se clasificaron como N (3,64% grasa, 3,37% proteína, 12,42% TS); 16,9% como HQ (5,46% de grasa, 4,01% de proteína y 14,82% de TS) y 41,2% como PQ (2,71% grasa, 3,08% proteína y 10,6% TS). Los modelos discriminantes para el búfalo de agua y la leche de vaca fueron capaces de clasificar la leche en los grupos N y PQ con una precisión >90% y en el grupo HQ con >85% de precisión.

19.
J Appl Physiol (1985) ; 112(4): 671-80, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22134700

RESUMO

Sleep is associated with marked alterations in ventilatory control that lead to perturbations in respiratory timing, breathing pattern, ventilation, pharyngeal collapsibility, and sleep-related breathing disorders (SRBD). Mouse models offer powerful insight into the pathogenesis of SRBD; however, methods for obtaining the full complement of continuous, high-fidelity respiratory, electroencephalographic (EEG), and electromyographic (EMG) signals in unrestrained mice during sleep and wake have not been developed. We adapted whole body plethysmography to record EEG, EMG, and respiratory signals continuously in unrestrained, unanesthetized mice. Whole body plethysmography tidal volume and airflow signals and a novel noninvasive surrogate for respiratory effort (respiratory movement signal) were validated against simultaneously measured gold standard signals. Compared with the gold standard, we validated 1) tidal volume (correlation, R(2) = 0.87, P < 0.001; and agreement within 1%, P < 0.001); 2) inspiratory airflow (correlation, R(2) = 0.92, P < 0.001; agreement within 4%, P < 0.001); 3) expiratory airflow (correlation, R(2) = 0.83, P < 0.001); and 4) respiratory movement signal (correlation, R(2) = 0.79-0.84, P < 0.001). The expiratory airflow signal, however, demonstrated a decrease in amplitude compared with the gold standard. Integrating respiratory and EEG/EMG signals, we fully characterized sleep and breathing patterns in conscious, unrestrained mice and demonstrated inspiratory flow limitation in a New Zealand Obese mouse. Our approach will facilitate studies of SRBD mechanisms in inbred mouse strains and offer a powerful platform to investigate the effects of environmental and pharmacological exposures on breathing disturbances during sleep and wakefulness.


Assuntos
Pletismografia Total , Polissonografia , Respiração , Sono , Animais , Eletroencefalografia , Eletromiografia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Volume de Ventilação Pulmonar
20.
Prostate Cancer Prostatic Dis ; 15(4): 359-64, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22801071

RESUMO

BACKGROUND: Prostate cancer (PCa) is a common malignancy and a leading cause of cancer death among men in the United States with African-American (AA) men having the highest incidence and mortality rates. Given recent results from admixture mapping and genome-wide association studies for PCa in AA men, it is clear that many risk alleles are enriched in men with West African genetic ancestry. METHODS: A total of 77 ancestry informative markers (AIMs) within surrounding candidate gene regions were genotyped and haplotyped using Pyrosequencing in 358 unrelated men enrolled in a PCa genetic association study at the Howard University Hospital between 2000 and 2004. Sequence analysis of promoter region single-nucleotide polymorphisms (SNPs) to evaluate disruption of transcription factor-binding sites was conducted using in silico methods. RESULTS: Eight AIMs were significantly associated with PCa risk after adjusting for age and West African ancestry. SNP rs1993973 (intervening sequences) had the strongest association with PCa using the log-additive genetic model (P=0.002). SNPs rs1561131 (genotypic, P=0.007), rs1963562 (dominant, P=0.01) and rs615382 (recessive, P=0.009) remained highly significant after adjusting for both age and ancestry. We also tested the independent effect of each significantly associated SNP and rs1561131 (P=0.04) and rs1963562 (P=0.04) remained significantly associated with PCa development. After multiple comparisons testing using the false discovery rate, rs1993973 remained significant. Analysis of the rs156113-, rs1963562-rs615382l and rs1993973-rs585224 haplotypes revealed that the least frequently found haplotypes in this population were significantly associated with a decreased risk of PCa (P=0.032 and 0.0017, respectively). CONCLUSIONS: The approach for SNP selection utilized herein showed that AIMs may not only leverage increased linkage disequilibrium in populations to identify risk and protective alleles, but may also be informative in dissecting the biology of PCa and other health disparities.


Assuntos
População Negra/genética , Marcadores Genéticos , Neoplasias da Próstata/genética , África Ocidental , Idoso , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Genótipo , Haplótipos , Humanos , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/epidemiologia , Fatores de Risco , Estados Unidos
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