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1.
J Gen Intern Med ; 34(10): 2014-2020, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30945065

RESUMO

BACKGROUND: Measuring care coordination in administrative data facilitates important research to improve care quality. OBJECTIVE: To compare shared patient networks constructed from administrative claims data across multiple payers. DESIGN: Social network analysis of pooled cross sections of physicians treating prevalent colorectal cancer patients between 2003 and 2013. PARTICIPANTS: Surgeons, medical oncologists, and radiation oncologists identified from North Carolina Central Cancer Registry data linked to Medicare claims (N = 1735) and private insurance claims (N = 1321). MAIN MEASURES: Provider-level measures included the number of patients treated, the number of providers with whom they share patients (by specialty), the extent of patient sharing with each specialty, and network centrality. Network-level measures included the number of providers and shared patients, the density of shared-patient relationships among providers, and the size and composition of clusters of providers with a high level of patient sharing. RESULTS: For 24.5% of providers, total patient volume rank differed by at least one quintile group between payers. Medicare claims missed 14.6% of all shared patient relationships between providers, but captured a greater number of patient-sharing relationships per provider compared with the private insurance database, even after controlling for the total number of patients (27.242 vs 26.044, p < 0.001). Providers in the private network shared a higher fraction of patients with other providers (0.226 vs 0.127, p < 0.001) compared to the Medicare network. Clustering coefficients for providers, weighted betweenness, and eigenvector centrality varied greatly across payers. Network differences led to some clusters of providers that existed in the combined network not being detected in Medicare alone. CONCLUSION: Many features of shared patient networks constructed from a single-payer database differed from similar networks constructed from other payers' data. Depending on a study's goals, shortcomings of single-payer networks should be considered when using claims data to draw conclusions about provider behavior.


Assuntos
Redes Comunitárias/estatística & dados numéricos , Continuidade da Assistência ao Paciente/estatística & dados numéricos , Estudos de Coortes , Neoplasias Colorretais/terapia , Humanos , Revisão da Utilização de Seguros/estatística & dados numéricos , Medicare/estatística & dados numéricos , North Carolina , Padrões de Prática Médica/estatística & dados numéricos , Sistema de Registros , Estados Unidos
2.
Animal ; 11(4): 625-633, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27608852

RESUMO

In the dairy industry, excess dietary CP is consistently correlated with decreased conception rates. However, the source from which excess CP is derived and how it affects reproductive function in beef cattle is largely undefined. The objective of this experiment was to determine the effects of feeding excess metabolizable protein (MP) from feedstuffs differing in rumen degradability on ovulatory follicular dynamics, subsequent corpus luteum (CL) development, steroid hormone production and circulating amino acids (AA) in beef cows. Non-pregnant, non-lactating mature beef cows (n=18) were assigned to 1 of 2 isonitrogenous diets (150% of MP requirements) designed to maintain similar BW and body condition score (BCS) between treatments. Diets consisted of ad libitum corn stalks supplemented with corn gluten meal (moderate rumen undegradable protein (RUP); CGM) or soybean meal (low RUP; SBM). After a 20-day supplement adaptation period, cows were synchronized for ovulation. After 10 days of synchronization, gonadotropin releasing hormone (GnRH) was administered to reset ovarian follicular growth. Starting at GnRH administration and daily thereafter until spontaneous ovulation, transrectal ultrasonography was used to diagram ovarian follicular growth, and blood samples were collected for hormone, metabolite and AA analyses. After 7 days of visual detection of estrus, CL size was determined via ultrasound. Data were analyzed using the MIXED procedures of SAS. As designed, cow BW and BCS were not different (P⩾0.33). Ovulatory follicular wavelength, antral follicle count, ovulatory follicle size at dominance and duration of dominance were not different (P>0.13) between treatments. Cows supplemented with CGM had greater post-dominance ovulatory follicle growth, larger dominant follicles at spontaneous luteolysis, shorter proestrus, and larger ovulatory follicles (P⩽0.03) than SBM cows. No differences (P⩾0.44) in peak estradiol, ratio of estradiol to ovulatory follicle volume, or plasma urea nitrogen were observed. While CL volume and the ratio of progesterone to CL volume were not affected by treatment (P⩾0.24), CGM treated cows tended to have decreased (P=0.07) circulating progesterone 7 days post-estrus compared with SBM cows. Although total circulating plasma AA concentration did not differ (P=0.70) between treatments, CGM cows had greater phenylalanine (P=0.03) and tended to have greater leucine concentrations (P=0.07) than SBM cows. In summary, these data illustrate that excess MP when supplemented to cows consuming a low quality forage may differentially impact ovarian function depending on ruminal degradability of the protein source.


Assuntos
Bovinos/fisiologia , Glycine max/química , Folículo Ovariano/crescimento & desenvolvimento , Proteínas de Vegetais Comestíveis/metabolismo , Progesterona/sangue , Rúmen/metabolismo , Zea mays/química , Ração Animal/análise , Animais , Dieta/veterinária , Suplementos Nutricionais/análise , Feminino , Hormônio Liberador de Gonadotropina/farmacologia , Folículo Ovariano/efeitos dos fármacos , Proteínas de Vegetais Comestíveis/administração & dosagem
3.
Animal ; 11(4): 634-642, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27609083

RESUMO

In the dairy industry, excess dietary CP is consistently correlated with decreased conception rates. However, amount of excess CP effects on reproductive function in beef cattle is largely undefined. The objective of this experiment was to determine the effects of excess metabolizable protein (MP) supplementation from a moderately abundant rumen undegradable protein (RUP) source (corn gluten meal: 62% RUP) on ovarian function and circulating amino acid (AA) concentrations in beef cows consuming low quality forage. Non-pregnant, non-lactating beef cows (n=16) were allocated by age, BW and body condition score (BCS) to 1 of 2 isocaloric supplements designed to maintain BW for 60 days. Cows had ad libitum access to corn stalks and were individually offered a corn gluten meal-based supplement daily at 125% (MP125) or 150% (MP150) of National Research Council (NRC) MP requirements. After a 20-day supplement adaptation period, cows were synchronized for ovulation. After 10 days of synchronization, follicular growth was reset with gonadotropin releasing hormone. Daily thereafter, transrectal ultrasonography was performed to diagram ovarian follicular waves, and blood samples were collected for hormone, metabolite and AA analyses. After 7 days of observation of estrus, corpus luteum (CL) size was determined via ultrasound. Data were analyzed using the MIXED procedures of SAS. No differences (P⩾0.21) in BW and BCS existed throughout the study; however, plasma urea N at ovulation was greater (P=0.04) in MP150. Preovulatory ovarian follicle size at dominance, duration of dominance, size at spontaneous luteolysis, length of proestrus and wavelength were not different (P⩾0.11) between treatments. However, ovulatory follicles were larger (P=0.04) and average antral follicle count was greater (P=0.01) in MP150 than MP125. Estradiol concentration and ratio of estradiol to ovulatory follicle volume were not different due to treatment (P⩾0.25). While CL volume 7 days post-estrus was greater (P<0.01) in MP150 than MP125, circulating progesterone 7 days post-estrus and ratio of progesterone to CL volume were not different (P⩾0.21). Total AA were not different (P⩾0.76) at study initiation or completion; however, as a percent of total AA, branched-chain AA at ovulation were greater (P=0.02) in MP150. In conclusion, supplementation of CP at 150% of NRC MP requirements from a moderately undegradable protein source may enhance growth of the ovulatory follicle and subsequent CL compared with MP supplementation at 125% of NRC MP requirements.


Assuntos
Aminoácidos/sangue , Bovinos/fisiologia , Suplementos Nutricionais , Glutens/administração & dosagem , Ovário/fisiologia , Zea mays , Ração Animal/análise , Animais , Nitrogênio da Ureia Sanguínea , Corpo Lúteo/efeitos dos fármacos , Dieta/veterinária , Estradiol/sangue , Estro/efeitos dos fármacos , Feminino , Hormônio Liberador de Gonadotropina/administração & dosagem , Luteólise , Folículo Ovariano/efeitos dos fármacos , Ovulação/efeitos dos fármacos , Progesterona/sangue , Carne Vermelha , Rúmen/efeitos dos fármacos , Rúmen/metabolismo
4.
Domest Anim Endocrinol ; 46: 1-11, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24183757

RESUMO

Objectives were to examine effects of selenium (Se) supply and maternal nutritional plane during gestation on placental size at term and maternal endocrine profiles throughout gestation and early lactation. Ewe lambs (n = 84) were allocated to treatments that included Se supply of adequate Se (ASe; 11.5 µg/kg BW) or high Se (HSe; 77 µg/kg BW) initiated at breeding and nutritional plane of 60% (RES), 100% (CON), or 140% (EXC) of requirements beginning on day 40 of gestation. At parturition, lambs were removed from their dams, and ewes were transitioned to a common diet that met requirements of lactation. Blood samples were taken from a subset of ewes (n = 42) throughout gestation, during parturition, and throughout lactation to determine hormone concentrations. Cotyledon number was reduced (P = 0.03) in RES and EXC ewes compared with CON ewes. Placental delivery time tended (P = 0.08) to be shorter in HSe ewes than in ASe ewes, whereas placental delivery time was longer (P = 0.02) in RES ewes than in CON and EXC ewes. During gestation, maternal progesterone, estradiol-17ß, and GH were increased (P < 0.05) in RES ewes and decreased (P < 0.05) in EXC ewes compared with CON ewes. In contrast, maternal cortisol, IGF-I, prolactin, triiodothyronine, and thyroxine were decreased in RES ewes and increased in EXC ewes compared with CON ewes during gestation. Selenium supply did not alter maternal hormone profiles during gestation. During parturition and lactation, maternal hormone concentrations were influenced by both Se and maternal nutritional plane. During the parturient process, HSe ewes tended to have greater (P = 0.06) concentrations of estradiol-17ß than ASe ewes. Three hours after parturition a surge of GH was observed in ASe-RES ewes that was muted in HSe-RES ewes and not apparent in other ewes. Growth hormone area under the curve during the parturient process was increased (P < 0.05) in ASe-RES vs HSe-RES ewes. Ewes that were overfed during gestation had reduced (P < 0.05) estradiol-17ß but greater IGF-I, triiodothyronine, and thyroxine (P < 0.05) compared with RES ewes. Even though ewes were transitioned to a common diet after parturition, endocrine status continued to be affected into lactation. Moreover, it appears that gestational diet may partially affect lactational performance through altered endocrine status.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Fenômenos Fisiológicos da Nutrição Materna , Placenta/fisiologia , Selênio/administração & dosagem , Ovinos/fisiologia , Animais , Animais Recém-Nascidos , Suplementos Nutricionais , Estradiol/sangue , Feminino , Hormônio do Crescimento/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Lactação , Estado Nutricional , Placenta/metabolismo , Gravidez , Progesterona/sangue , Prolactina/sangue , Distribuição Aleatória , Ovinos/sangue , Tiroxina/sangue , Tri-Iodotironina/sangue
5.
Animal ; 7(9): 1500-7, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23764235

RESUMO

Dietary melatonin supplementation during mid- to late-gestation increased umbilical artery blood flow and caused disproportionate fetal growth. This melatonin-induced increase in umbilical artery blood flow may alter nutrient availability to the fetus, which may lead to alterations in fetal size. The objectives of the current experiment were to determine amino acid (AA) and glucose concentrations as well as AA and glucose flux across the uteroplacenta using a mid- to late-gestation model of intrauterine growth restriction supplemented with dietary melatonin as a 2 × 2 factorial design. At day 50 of gestation, 32 ewes were supplemented with 5 mg of melatonin (MEL) or no melatonin (CON) and were allocated to receive 100% (adequate; ADQ) or 60% (restricted; RES) of nutrient requirements. On day 130 of gestation, uterine and umbilical blood flows were determined via Doppler ultrasonography during a non-survival surgery. Blood samples were collected under general anesthesia from the maternal saphenous artery, gravid uterine vein, umbilical artery, and umbilical vein for AA analysis and glucose. Total α-AA concentrations in maternal artery and gravid uterine vein were decreased (P < 0.05) in RES v. ADQ fed ewes. Maternal arterial - venous difference in total α-AA was increased (P ⩽ 0.01) in RES v. ADQ fed ewes, while total uterine α-AA flux was not different (P > 0.40) across all treatment groups. Fetal venous - arterial difference in total α-AA as well as uteroplacental flux of total α-AA were decreased (P < 0.05) in CON-RES v. CON-ADQ, and similar (P > 0.20) in MEL-RES v. CON-ADQ. Maternal concentrations and uterine flux of branched-chain AA (BCAA) were not different across all treatment groups; however, fetal uptake of BCAA was decreased (P < 0.05) in CON-RES v. CON-ADQ, and similar (P > 0.20) in MEL-RES v. CON-ADQ. Uterine uptake of glucose was not different (P ⩾ 0.08) across all treatment groups, while uteroplacental uptake of glucose was increased (P ⩽ 0.05) in RES v. ADQ ewes. In conclusion, maternal nutrient restriction increased maternal arterial - venous difference in total α-AA, while total uterine α-AA flux was unaffected by maternal nutrient restriction. Melatonin supplementation did not impact maternal serum concentrations or uterine flux of glucose or AA; however, melatonin did improve fetal BCAA uptake during maternal nutrient restriction.


Assuntos
Aminoácidos/sangue , Suplementos Nutricionais , Retardo do Crescimento Fetal/dietoterapia , Fenômenos Fisiológicos da Nutrição Materna/fisiologia , Melatonina/farmacologia , Circulação Placentária/efeitos dos fármacos , Animais , Glicemia , Cromatografia Líquida de Alta Pressão/veterinária , Feminino , Fígado/metabolismo , Modelos Biológicos , Gravidez , Ovinos
6.
J Anim Sci ; 90(1): 325-33, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21873539

RESUMO

Many areas of the western United States have soils that have increased Se content, and ruminants grazing these rangelands may ingest increased quantities of Se. In addition, high-energy diets or increased Se intake may induce gut inflammation. The objective of this study was to evaluate the effects of maternal plane of nutrition and increased dietary Se during gestation on inflammatory responses in neonatal lamb ileal tissue, a major immune organ. Rambouillet ewes (age = 240 ± 17 d; initial BW = 52.1 ± 6.2 kg) were allocated to 4 treatments arranged in a 2 × 2 factorial. Factors included Se [adequate Se (ASe, 11.5 µg/kg of BW) or high Se (HSe, 77.0 µg/kg of BW)] initiated at breeding, and nutritional plane [100% (CON) or 140% (HIH) of requirements] initiated at d 40 of gestation. Ewes were fed individually from d 40, and lambs were removed at parturition and fed artificial colostrum and milk replacer. Lambs were necropsied at 20 d of age, and ileal tissues were sampled for immunoblotting and real-time quantitative reverse-transcription PCR analyses. The ASe-HIH and HSe-CON treatments had no effect (P = 0.179) on inflammatory signaling compared with ASe-CON. However, greater inflammatory signaling was detected in the HSe-HIH group, as shown by increased (P < 0.05) mRNA expression of tumor necrosis factor-α and chemotaxis IL-8. Consistently, phosphorylation of c-Jun N-terminal kinase, a primary inflammatory signaling mediator, was greater (P < 0.05) in the HSe-HIH group compared with other treatments. Consistent with cytokine expression, mast cell density was less in the HSe-CON group than in other treatments. The expression of transforming growth factor ß mRNA was greater (P < 0.05) in the HSe-HIH group; consistently, collagen content was increased in the HSe-HIH group compared with the ASe-CON group (P < 0.05). In conclusion, independently, neither HSe nor HIH had major effects on inflammation, but in combination, these maternal treatments induced an inflammatory response in the neonatal intestine.


Assuntos
Animais Recém-Nascidos/imunologia , Estado Nutricional , Prenhez , Selênio/farmacologia , Carneiro Doméstico/imunologia , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Western Blotting/veterinária , Citocinas/metabolismo , Dieta/veterinária , Feminino , Íleo/imunologia , Íleo/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Masculino , Fenômenos Fisiológicos da Nutrição Materna , Gravidez , Fenômenos Fisiológicos da Nutrição Pré-Natal , RNA Mensageiro/análise , Distribuição Aleatória , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Carneiro Doméstico/crescimento & desenvolvimento , Carneiro Doméstico/fisiologia
7.
J Anim Sci ; 83(12): 2762-74, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16282614

RESUMO

Two experiments were conducted to evaluate the effects of dietary Zn and Fe supplementation on mineral excretion, body composition, and mineral status of nursery pigs. In Exp. 1 (n = 24; 6.5 kg; 16 to 20 d of age) and 2 (n = 24; 7.2 kg; 19 to 21 d of age), littermate crossbred barrows were weaned and allotted randomly by BW, within litter, to dietary treatments and housed individually in stainless steel pens. In Exp. 1, Phases 1 (d 0 to 7) and 2 (d 7 to 14) diets (as-fed basis) were: 1) NC (negative control, no added Zn source); 2) ZnO (NC + 2,000 mg/kg as Zn oxide); and 3) ZnM (NC + 2,000 mg/kg as Zn Met). In Exp. 2, diets for each phase (Phase 1 = d 0 to 7; Phase 2 = d 7 to 21; Phase 3 = d 21 to 35) were the basal diet supplemented with 0, 25, 50, 100, and 150 mg/kg Fe (as-fed basis) as ferrous sulfate. Orts, feces, and urine were collected daily in Exp. 1; whereas pigs had a 4-d adjustment period followed by a 3-d total collection period (Period 1 = d 5 to 7; Period 2 = d 12 to 14; Period 3 = d 26 to 28) during each phase in Exp. 2. Blood samples were obtained from pigs on d 0, 7, and 14 in Exp. 1 and d 0, 7, 21, and 35 in Exp. 2 to determine hemoglobin (Hb), hematocrit (Hct), and plasma Cu, (PCu), Fe (PFe), and Zn (PZn). Pigs in Exp. 1 were killed at d 14 (mean BW = 8.7 kg) to determine whole-body, liver, and kidney mineral concentrations. There were no differences in growth performance in Exp. 1 or 2. In Exp. 1, pigs fed ZnO or ZnM diets had greater (P < 0.001) dietary Zn intake during the 14-d study and greater fecal Zn excretion during Phase 2 compared with pigs fed the NC diet. Pigs fed 2,000 mg/kg, regardless of Zn source, had greater (P < 0.010) PZn on d 7 and 14 than pigs fed the NC diet. Whole-body Zn, liver Fe and Zn, and kidney Cu concentrations were greater (P < 0.010), whereas kidney Fe and Zn concentrations were less (P < 0.010) in pigs fed pharmacological Zn diets than pigs fed the NC diet. In Exp. 2, dietary Fe supplementation tended to increase (linear, P = 0.075) dietary DMI, resulting in a linear increase (P < 0.050) in dietary Fe, Cu, Mg, Mn, P, and Zn intake. Subsequently, a linear increase (P < 0.010) in fecal Fe and Zn excretion was observed. Increasing dietary Fe resulted in a linear increase in Hb, Hct, and PFe on d 21 (P < 0.050) and 35 (P < 0.010). Results suggest that dietary Zn or Fe additions increase mineral status of nursery pigs. Once tissue mineral stores are loaded, dietary minerals in excess of the body's requirement are excreted.


Assuntos
Composição Corporal/efeitos dos fármacos , Compostos Ferrosos/farmacologia , Metionina/análogos & derivados , Compostos Organometálicos/farmacologia , Suínos/crescimento & desenvolvimento , Óxido de Zinco/farmacologia , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Suplementos Nutricionais , Masculino , Metionina/farmacologia , Minerais/metabolismo , Aumento de Peso/efeitos dos fármacos
9.
Org Lett ; 3(21): 3373-5, 2001 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-11594837

RESUMO

[structure: see text]. We report the incorporation of a thioamide linkage between the i + 2 and i + 3 residues of the type II' beta-turn of a peptide known to fold into a beta-hairpin conformation. Two-dimensional NMR spectroscopy and circular dichroism spectroscopy indicate that the thioxo peptide adopts a hairpin conformation similar to that of the oxo peptide and that the hairpin conformation persists at elevated temperatures. The results show that a thioamide linkage is compatible with beta-sheet secondary structure.


Assuntos
Peptídeos/síntese química , Tioamidas/química , Dicroísmo Circular , Modelos Moleculares , Ressonância Magnética Nuclear Biomolecular , Peptídeos/química , Desnaturação Proteica/efeitos dos fármacos , Estrutura Secundária de Proteína/efeitos dos fármacos , Temperatura , Tioamidas/farmacologia
10.
Gastroenterology ; 111(3): 597-603, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8780562

RESUMO

BACKGROUND & AIMS: Because the mode of Crohn's disease inheritance is unknown, age-adjusted risk estimates and knowledge of disease characteristics will aid genetic counseling and modeling. The aim of this study is to determine the prevalence of familial occurrence of inflammatory bowel disease in first-degree relatives of patients with Crohn's disease and estimate their age-adjusted risks. It also evaluates agreement in disease characteristics between generations within families with a history of Crohn's disease. METHODS: Six hundred forty patients with Crohn's disease and 800 control subjects were questioned about the occurrence of inflammatory bowel disease in their first-degree relatives. Agreement for age at diagnosis, initial disease location, disease behavior, and number of bowel resections was determined in 68 families with two or more members affected and compared with data in 100 unrelated patients with Crohn's disease. RESULTS: Probands with Crohn's disease had a more frequent positive family history than controls. The age at diagnosis between probands with and without a positive family history was insignificant. Crude and age-adjusted risk elements were higher in relatives of patients, especially daughters, compared with those of controls. The age at diagnosis was older for parents than offspring but similar between siblings. Initial disease location was especially striking between siblings. CONCLUSIONS: This study confirms familial aggregation and a high degree of disease concordance in Crohn's disease. The age at diagnosis and initial disease location was especially strong within generations.


Assuntos
Doença de Crohn/genética , Adolescente , Adulto , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Viés , Estudos de Casos e Controles , Saúde da Família , Feminino , Humanos , Masculino , Prontuários Médicos , Pessoa de Meia-Idade , Fatores de Risco
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