Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 95
Filtrar
1.
Urol Oncol ; 41(5): 211-218, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36266219

RESUMO

Bacillus Calmette-Guerin (BCG) remains the only FDA-approved first-line therapy in patients with high-risk non-muscle invasive bladder cancer. Recurrences, even after adequate BCG therapy, are common and the efficacy of second-line therapies remains modest. Therefore, early identification of patients likely to recur and treatment after recurrence remain critical unmet needs in the clinical care of bladder cancer patients. To address these deficits, a better understanding of the mechanisms of resistance to BCG-therapy is needed. The virtual update of the International Bladder Cancer Network (IBCN) on the biology of response to BCG focused on potential mechanisms and markers of resistance to intravesical BCG therapy. The insights from this meeting will be highlighted and put into context of previously reported mechanisms of resistance to BCG in this review.


Assuntos
Neoplasias não Músculo Invasivas da Bexiga , Neoplasias da Bexiga Urinária , Humanos , Adjuvantes Imunológicos/uso terapêutico , Vacina BCG/uso terapêutico , Imunoterapia , Administração Intravesical , Neoplasias da Bexiga Urinária/tratamento farmacológico , Biologia , Invasividade Neoplásica , Recidiva Local de Neoplasia/tratamento farmacológico
2.
Hormones (Athens) ; 19(2): 205-214, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32077039

RESUMO

PURPOSE: Testosterone (T) plays an important role in men's health and its deficiency is linked with poorer health. However, the role of nutritional and lifestyle factors in T regulation and production remains unclear. The objectives are to comprehensively test the cross-sectional associations of nutritional and lifestyle factors with T deficiency and to validate the associations in the NHANES survey. METHODS: We performed weighted multivariable logistic regression analysis to examine the association of 173 nutritional and lifestyle factors with T deficiency (total testosterone ≤ 3.5 ng/mL) in NHANES III as the discovery set (mean age 41). We controlled for multiple comparisons with a false discovery rate (FDR) < 5% and replicated in NHANES 1999-2004 (mean age 44). RESULTS: We identified seven nutritional factors as being inversely associated with T deficiency in NHANES 1999-2004, namely dietary intake of vitamin A, protein, saturated fatty acids, monounsaturated fatty acids, total fats, saturated fatty acid 16:0, and phosphorus. In a multivariable model, only vitamin A intake remained significantly associated with T deficiency (OR 0.97, 95% CI 0.94-0.99). Principal component analysis suggested that the two principal components, (1) dietary fats, protein, and phosphorous and (2) total vitamin A, may be associated with T deficiency. CONCLUSION: Our systematic evaluation provided new insight into the modifiable factors that could play a role in the regulation of T production. This study has the potential to contribute to the current body of literature which seeks to formulate a clinical definition of T deficiency after taking into account nutritional and lifestyle factors.


Assuntos
Ingestão de Alimentos , Estilo de Vida , Estado Nutricional , Testosterona/deficiência , Adulto , Estudos Transversais , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Análise de Componente Principal , Testosterona/sangue , Estados Unidos
3.
Prostate Cancer Prostatic Dis ; 20(3): 300-304, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28349981

RESUMO

BACKGROUND: Physician practices that offer ancillary medical services may refer their patients for such services, a process known as self-referral. We wanted to evaluate how utilization and cost of care differ for men diagnosed with prostate cancer in a self-referral practice (SRP) compared to a traditional urologic practice. METHODS: A total of 17 982 men aged 66 years and older diagnosed with localized prostate cancer from 2006 to 2009 were identified from the Texas Cancer Registry. A total of 13 SRPs in the state of Texas were evaluated. We used multilevel logistic regression models that evaluated the odds of receiving a specific type of treatment. RESULTS: Men diagnosed in SRPs were more likely to receive upfront treatment (vs watchful waiting/active surveillance) than men diagnosed by traditional practices (92.7% vs 89%; adjusted odds ratio (AOR) 1.61, 95% confidence interval (CI) 1.30-2.00; P<0.001) and were more likely to be treated with external beam radiation (47.4% vs 34.1%; AOR 1.59, 95% CI 1.37-1.84; P<0.001). This persisted for both favorable and unfavorable risk cancer. Median annual prostate cancer care cost was $2460 (95% CI $1663-$3368) higher for men diagnosed by SRPs. Limitations include data limited to men aged 65 years or older and geographic concentration of SRPs in Texas may not depict nationwide patterns. CONCLUSIONS: Older men diagnosed with prostate cancer in SRPs are more likely to undergo upfront treatment and to receive radiation treatment. This may increase appropriate treatment of unfavorable disease but contribute to overtreatment of favorable disease.


Assuntos
Neoplasias da Próstata/radioterapia , Radioterapia/instrumentação , Idoso , Idoso de 80 Anos ou mais , Custos de Cuidados de Saúde , Humanos , Masculino , Neoplasias da Próstata/diagnóstico , Radioterapia/economia , Resultado do Tratamento , Urologistas
4.
J Stored Prod Res ; 69: 22-25, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27990030

RESUMO

We assessed the performance of hermetic triple layer Purdue Improved Crop Storage (PICS) bags for protecting Hibiscus sabdariffa grain against storage insects. The major storage pest in the grain was a bruchid, Spermophagus sp.. When we stored infested H. sabdariffa grain for six months in the woven polypropylene bags typically used by farmers, the Spermophagus population increased 33-fold over that initially present. The mean number of emergence holes per 100 seeds increased from 3.3 holes to 35.4 holes during this time period, while grain held for the same length of time in PICS bags experienced no increase in the numbers of holes. Grain weight loss in the woven control bags was 8.6% while no weight loss was observed in the PICS bags. Seed germination rates of grain held in woven bags for six months dropped significantly while germination of grain held in PICS bags did not change from the initial value. PICS bags can be used to safely store Hibiscus grain after harvest to protect against a major insect pest.

5.
Minerva Urol Nefrol ; 67(1): 47-53, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25424387

RESUMO

Over the past decade, the robotic assisted radical prostatectomy (RARP) has grown increasingly popular and quickly equated itself as the most commonly used modality to treat locally-confined prostate cancer. Despite increased utilization, there is limited comparative research demonstrating superiority for RARP over the conventional radical retropubic prostatectomy (RRP). Furthermore, though perioperative and short-term oncologic outcomes are equivalent if not superior for the robotic approach, the optimal utilization of robotic technology remains to be determined with cost serving as a primary driver. In this review, we performed a literature search to identify comparative effectiveness research as it pertains to RARP versus RRP. We performed a PubMed literature search for a review of articles published between 2000 and 2014 using the following keywords to identify pertinent research: "robot or robotic prostatectomy", "open or retropubic prostatectomy", "cost", "resource utilization". Long-term data comparing RARP and RRP remains limited, though short-term positive surgical margins, biochemical recurrence-free survival, and need for adjuvant therapy appear at least equivocal, if not in favor of RARP versus RRP. Functional outcomes including return of continence and potency favor RARP while cost still favors RRP. Nonetheless, the generalization of results remains difficult with surgeon volume playing a large role in improving efficiency and quality. For the foreseeable future, an increasing number of prostatectomies will continue to be performed robotically. Though RARP appears to offer improved functional outcomes with good short-term oncologic outcomes, there is a need for longer-term studies to assess the true value of RARP. Outcomes aside, rigorous, prospective randomized-controlled trials must also be performed on the cost-effectiveness of RARP to determine its overall utility in an era of health care delivery reform.


Assuntos
Prostatectomia/economia , Prostatectomia/métodos , Procedimentos Cirúrgicos Robóticos/economia , Análise Custo-Benefício , Medicina Baseada em Evidências , Humanos , Los Angeles , Masculino , Neoplasias da Próstata/cirurgia , Procedimentos Cirúrgicos Robóticos/instrumentação , Procedimentos Cirúrgicos Robóticos/normas , Resultado do Tratamento
6.
J Urol ; 186(6): 2245-8, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22014805

RESUMO

PURPOSE: Percent of embryonal carcinoma and lymphovascular invasion in the primary tumor are risk factors for occult retroperitoneal metastatic disease. High risk patients with clinical stage I and IIA nonseminomatous germ cell tumor who underwent primary retroperitoneal lymph node dissection were identified to discern any other risk factors for metastatic disease. MATERIALS AND METHODS: Patients who had undergone retroperitoneal lymph node dissection at our institution from 1993 to 2009 were identified and clinical charts were reviewed. A total of 90 patients with orchiectomy specimens containing more than 30% embryonal carcinoma who underwent primary retroperitoneal lymph node dissection were identified and perioperative data were obtained. RESULTS: Of 353 patients 90 (25%) had greater than 30% embryonal carcinoma and underwent primary retroperitoneal lymph node dissection. Of these patients 45 (50%) had lymphovascular invasion. Median followup was 1.1 years. Positive lymph nodes identified at retroperitoneal lymph node dissection were noted in 30 (46%) and 15 (60%) patients with clinical stage I vs clinical stage II disease. On multivariate analysis embryonal carcinoma (OR 1.02, 95% CI 1.00-1.04) and lymphovascular invasion (OR 3.52, 95% CI 1.43-8.67) were associated with positive lymph nodes at retroperitoneal lymph node dissection. The positive predictive value for 100% embryonal carcinoma was 65.5%, although the negative predictive value for 30% embryonal carcinoma was 85.7%. CONCLUSIONS: Embryonal carcinoma and lymphovascular invasion were significantly and independently associated with the risk of occult retroperitoneal metastatic disease. These results should be considered when counseling patients about appropriate treatment options.


Assuntos
Neoplasias Embrionárias de Células Germinativas/secundário , Neoplasias Testiculares/patologia , Adulto , Humanos , Metástase Linfática , Masculino , Estadiamento de Neoplasias , Neoplasias Embrionárias de Células Germinativas/cirurgia , Valor Preditivo dos Testes , Espaço Retroperitoneal , Fatores de Risco , Neoplasias Testiculares/cirurgia
7.
Vet Rec ; 168(15): 407, 2011 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-21493454

RESUMO

To establish the current status of canine hydrotherapy in the UK and to ascertain information regarding the current use of hydrotherapy, a questionnaire was sent to 152 hydrotherapy centres throughout the UK, from which 89 responded. Hydrotherapy was found to be a rapidly growing business. Stand-alone centres were in existence; however, many centres were connected to other businesses, including boarding kennels and general practice veterinary surgeries. The dogs using the facility were mainly pedigree breeds, particularly labrador retrievers (30 per cent), and the most commonly encountered conditions were rupture of the cranial cruciate ligament (25 per cent), hip dysplasia (24 per cent) and osteoarthritis (18 per cent). The proportion of qualified versus unqualified staff varied between centres, highlighting a need for improved regulation of this aspect of the industry. However, all the dogs treated by the hydrotherapy centres surveyed were direct veterinary referrals, suggesting a good degree of professionalism in the field and a high regard for the benefits of hydrotherapy.


Assuntos
Doenças do Cão/terapia , Hidroterapia/veterinária , Medicina Veterinária/métodos , Animais , Lesões do Ligamento Cruzado Anterior , Cães , Feminino , Displasia Pélvica Canina/terapia , Masculino , Osteoartrite/terapia , Osteoartrite/veterinária , Linhagem , Encaminhamento e Consulta , Inquéritos e Questionários , Resultado do Tratamento
8.
Theor Appl Genet ; 121(7): 1227-37, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20563549

RESUMO

The ß-, γ- and δ-kafirin genes were sequenced from 35 Sorghum genotypes to investigate the allelic diversity of seed storage proteins. A range of grain sorghums, including inbred parents from internationally diverse breeding programs and landraces, and three wild Sorghum relatives were selected to encompass an extensive array of improved and unimproved germplasm in the Eusorghum. A single locus exists for each of the expressed kafirin-encoding genes, unlike the multigenic α-kafirins. Significant diversity was found for each locus, with the cysteine-rich ß-kafirin having four alleles, including the first natural null mutant reported for this prolamin subfamily. This allele contains a frame shift insertion at +206 resulting in a premature stop codon. SDS-PAGE revealed that lines with this allele do not produce ß-kafirin. An analysis of flour viscosity reveals that these ß-kafirin null lines have a difference in grain quality, with significantly lower viscosity observed over the entire Rapid ViscoAnalyser time course. There was less diversity at the protein level within the cysteine-rich γ-kafirin, with only two alleles in the cultivated sorghums. There were only two alleles for the δ-kafirin locus among the S. bicolor germplasm, with one allele encoding ten extra amino acids, of which five were methionine residues, with an additional methionine resulting from a nucleotide substitution. This longer allele encodes a protein with 19.1% methionine. The Asian species, S. propinquum, had distinct alleles for all three kafirin genes. We found no evidence for selection on the three kafirin genes during sorghum domestication even though the δ-kafirin locus displayed comparatively low genetic variation. This study has identified genetic diversity in all single copy seed storage protein genes, including a null mutant for ß-kafirin in Sorghum.


Assuntos
Alelos , Mutação da Fase de Leitura/genética , Genes de Plantas , Proteínas de Plantas/genética , Prolaminas/genética , Sorghum/genética , Sequência de Bases , Mapeamento Cromossômico , Cisteína/metabolismo , Grão Comestível/química , Grão Comestível/genética , Grão Comestível/metabolismo , Genótipo , Metionina/química , Metionina/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Alinhamento de Sequência , Sorghum/química , Sorghum/metabolismo
10.
J Exp Biol ; 212(Pt 4): 550-65, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19181903

RESUMO

Animals in their natural environments are confronted with a regular need to perform rapid accelerations (for example when escaping from predators or chasing prey). Such acceleration requires net positive mechanical work to be performed on the centre of mass by skeletal muscle. Here we determined how pelvic limb joints contribute to the mechanical work and power that are required for acceleration in galloping quadrupeds. In addition, we considered what, if any, biomechanical strategies exist to enable effective acceleration to be achieved. Simultaneous kinematic and kinetic data were collected for racing greyhounds undergoing a range of low to high accelerations. From these data, joint moments and joint powers were calculated for individual hindlimb joints. In addition, the mean effective mechanical advantage (EMA) of the limb and the ;gear ratio' of each joint throughout stance were calculated. Greatest increases in joint work and power with acceleration appeared at the hip and hock joints, particularly in the lead limb. Largest increases in absolute positive joint work occurred at the hip, consistent with the hypothesis that quadrupeds power locomotion by torque about the hip. In addition, hindlimb EMA decreased substantially with increased acceleration - a potential strategy to increase stance time and thus ground impulses for a given peak force. This mechanism may also increase the mechanical advantage for applying the horizontal forces necessary for acceleration.


Assuntos
Cães/fisiologia , Membro Posterior/fisiologia , Locomoção , Animais , Fenômenos Biomecânicos , Articulações/fisiologia , Modelos Biológicos , Pelve/fisiologia
11.
J Anat ; 213(4): 373-82, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19034998

RESUMO

We provide quantitative muscle-tendon architecture and geometry data for the racing greyhound thoracic limb. Muscle mass, belly length, fascicle lengths, pennation angles and moment arms were measured, as were tendon masses and lengths. Maximum isometric force and maximum power were estimated for muscles, and maximum stress and strain were estimated for tendons. Results are compared with other fast quadrupedal runners, and to previously published data in mixed-breed dogs. The implications of the functional adaptations of the greyhound thoracic limb for sprinting performance are discussed. The thoracic limb was found to benefit from a similar proportion of locomotor muscle mass to the pelvic limb, suggesting that it may be used to some extent in propulsion, or alternatively that stabilisation is very important in this animal. Extrinsic muscles, especially latissimus dorsi and pectoralis profundus, were predicted to be powerful and important for generating net positive work during accelerations. Proximal biarticular muscles show specialisation toward preventing collapse of the shoulder and elbow joints to enable strut-like limb function, or some form of dynamic control. Distal muscles did not appear specialised for elastic energy storage, a functional difference to pelvic limb muscles, and the equivalents in horse thoracic limbs. The greyhound thoracic limb appears to possess substantial differences from both that of more 'sub-maximal specialist' quadrupeds, and from the greyhound pelvic limb.


Assuntos
Cães/anatomia & histologia , Membro Anterior , Marcha , Músculo Esquelético/anatomia & histologia , Adaptação Fisiológica , Animais , Fenômenos Biomecânicos , Cães/fisiologia , Contração Isométrica , Articulações/anatomia & histologia , Articulações/fisiologia , Músculo Esquelético/fisiologia , Amplitude de Movimento Articular , Tendões/anatomia & histologia , Tendões/fisiologia
12.
J Anat ; 213(4): 361-72, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18657259

RESUMO

We provide quantitative anatomical data on the muscle-tendon architecture and geometry of the pelvic limb of an elite sprint athlete, the racing greyhound. Specifically, muscle masses, muscle lengths, fascicle lengths, pennation angles and muscle moment arms were measured. Maximum isometric force and power of muscles, the maximum muscle torque at joints and tendon stress and strain were estimated. We compare data with that published for a generalized breed of canid, and other cursorial mammals such as the horse and hare. The pelvic limb of the racing greyhound had a relatively large volume of hip extensor muscle, which is likely to be required for power production. Per unit body mass, some pelvic limb muscles were relatively larger than those in less specialized canines, and many hip extensor muscles had longer fascicle lengths. It was estimated that substantial extensor moments could be created about the tarsus and hip of the greyhound allowing high power output and potential for rapid acceleration. The racing greyhound hence possesses substantial specializations for enhanced sprint performance.


Assuntos
Cães/anatomia & histologia , Cães/fisiologia , Marcha , Membro Posterior , Articulações/anatomia & histologia , Músculo Esquelético/anatomia & histologia , Adaptação Fisiológica , Animais , Fenômenos Biomecânicos , Contração Isométrica/fisiologia , Articulações/fisiologia , Músculo Esquelético/fisiologia , Pelve , Amplitude de Movimento Articular , Tendões/anatomia & histologia , Tendões/fisiologia
13.
J Anat ; 210(4): 491-505, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17428206

RESUMO

We provide quantitative anatomical data on the muscle-tendon architecture of the hare thoracic limb (specifically muscle mass, fascicle length, pennation angle, tendon mass and length). In addition, moment arms of major thoracic limb muscles were measured. Maximum isometric force and power of muscles, the moment of force about a joint, and tendon stress and strain were estimated. Data are compared with those from other cursorial mammals. The thoracic limb of the hare consists predominantly of extrinsic musculature with long parallel fascicles, specialised for generating force over a large range. A large shoulder flexor/elbow extensor muscle mass is present, in particular Triceps brachii. The pennate nature of the long head of this muscle suggests it has an important role in stabilising the elbow joint during stance, whilst moment arm curves suggest that it may also play a role in initiating shoulder flexion. In addition, Supraspinatus and Infraspinatus are capable of generating high forces, potentially to stabilise the shoulder joint during the stance phase of locomotion. Supraspinatus may in addition play an important role in forelimb protraction. The Subscapularis muscle was capable of generating surprisingly high forces, suggesting that the hare must be able to withstand/produce high forces during activities that need medio-lateral stability, such as turning. Distally, tendons were relatively short, showing little potential for elastic energy storage when compared with both their pelvic limb counterparts and their equivalents in the horse thoracic limb. Thus, a 'stiffer' thoracic limb may be beneficial in terms of behaving like a strut, simply supporting and deflecting the body during high-speed running. This more distal/less proximal distribution of limb mass is also likely to be important in retaining the manipulative/adaptive/non-locomotor capabilities of the limb.


Assuntos
Adaptação Fisiológica , Membro Anterior/anatomia & histologia , Marcha , Lebres/anatomia & histologia , Animais , Fenômenos Biomecânicos , Membro Anterior/fisiologia , Lebres/fisiologia , Contração Isométrica , Articulações/anatomia & histologia , Articulações/fisiologia , Movimento , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/fisiologia , Tendões/anatomia & histologia , Tendões/fisiologia
14.
J Anat ; 210(4): 472-90, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17362487

RESUMO

We provide quantitative anatomical data on the muscle-tendon architecture of the hare pelvic limb (specifically muscle mass, fascicle length, pennation angle, tendon mass and length). In addition, moment arms of major pelvic limb muscles were measured. Maximum isometric force and power of muscles, the moment of force about a joint, and tendon stress and strain were estimated. Data are compared with published data for other cursorial mammals such as the horse and dog, and a non-specialised Lagamorph, the rabbit. The pelvic limb of the hare was found to contain substantial amounts of hip extensor and adductor/abductor muscle volume, which is likely to be required for power production and stability during rapid turning. A proximal to distal reduction in muscle volume and fascicle length was also observed, as is the case in other cursorial quadrupeds, along with a reduction in distal limb mass via the replacement of muscle volume by long distal limb tendons, capable of storing large amounts of elastic energy. The majority of hare pelvic limb muscle moment arms varied with joint position, giving the hare the capacity to vary muscle function with limb posture and presumably different locomotor activities.


Assuntos
Adaptação Fisiológica , Marcha , Lebres/anatomia & histologia , Membro Posterior/anatomia & histologia , Animais , Fenômenos Biomecânicos , Lebres/fisiologia , Membro Posterior/fisiologia , Contração Isométrica , Articulações/anatomia & histologia , Músculo Esquelético/anatomia & histologia , Resistência Física , Amplitude de Movimento Articular , Tendões/anatomia & histologia
15.
J Anim Sci ; 83(2): 386-92, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15644511

RESUMO

Three experiments were conducted to determine the effects of phytase, excess Zn, or their combination in diets for nursery pigs. In all experiments, treatments were replicated with five to seven pens of six to seven pigs per pen, dietary Ca and available P (aP) levels were decreased by 0.1% when phytase was added to the diets, excess Zn was added as ZnO, a basal level of 127 mg/kg of Zn (Zn sulfate) was present in all diets, and the experimental periods were 19 to 21 d. In Exp. 1, pigs (5.7 kg and 18 d of age) were fed two levels of phytase (0 or 500 phytase units/kg) and three levels of excess Zn (0, 1,000, or 2,000 ppm) in a 2 x 3 factorial arrangement. Added Zn linearly increased ADG and ADFI during Phase 1 (P = 0.01 to 0.06), Phase 2 (P = 0.02 to 0.09), and overall (P = 0.01 to 0.02). Gain:feed was linearly increased by Zn during Phase 1 (P = 0.01) but not at other times. Dietary phytase decreased ADG in pigs fed 1,000 or 2,000 ppm Zn during Phase 2 (Zn linear x phytase interaction; P = 0.10), did not affect (P = 0.27 to 0.62) ADFI during any period, and decreased G:F during Phase 2 (P = 0.01) and for the overall (P = 0.07) period. Plasma Zn was increased by supplemental Zn (Zn quadratic, P = 0.01) but not affected (P = 0.70) by phytase addition. In Exp. 2, pigs (5.2 kg and 18 d of age) were fed two levels of phytase (0 or 500 phytase units/kg) and two levels of Zn (0 or 2,000 ppm) in a 2 x 2 factorial arrangement. Supplemental Zn increased ADG and G:F during Phase 2 (P = 0.02 to 0.09) and overall (P = 0.07 to 0.08), but it had no effect (P = 0.11 to 0.89) on ADG during Phase 1 or ADFI during any period. Phytase supplementation increased ADG (P = 0.06) and G:F (P = 0.01) during Phase 2. Gain:feed was greatest for pigs fed 2,000 ppm Zn and phytase (Zn x phytase interaction; P = 0.01). Bone (d 20) and plasma Zn (d 7 and 20) were increased (P = 0.01) by added Zn but not affected (P = 0.51 to 0.90) by phytase. In Exp. 3, pigs (5.7 kg and 19 d of age) were fed a basal diet or the basal diet with Ca and aP levels decreased by 0.10% and these two diets with or without 500 phytase units/kg. Supplemental phytase had no effect (P = 0.21 to 0.81) on growth performance. Reduction of dietary Ca and aP decreased (P = 0.02 to 0.08) ADG, ADFI, and G:F for the overall data. These results indicate that excess dietary supplemental Zn increases ADG and plasma and bone Zn concentrations. Dietary phytase did not affect plasma or bone Zn concentrations.


Assuntos
6-Fitase/farmacologia , Dieta/veterinária , Suínos/crescimento & desenvolvimento , Aumento de Peso/efeitos dos fármacos , Zinco/farmacologia , Ração Animal/análise , Animais , Cóccix/química , Suplementos Nutricionais , Feminino , Crescimento/efeitos dos fármacos , Crescimento/fisiologia , Masculino , Suínos/fisiologia , Desmame , Zinco/sangue
16.
J Anim Sci ; 82(3): 705-14, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15032427

RESUMO

Two experiments were conducted to determine the effect of phytase on plasma metabolites and AA and energy digestibility in swine. In Exp. 1, eight barrows (surgery BW = 52 kg) were fitted with steered ileocecal cannulas. The experiment was a Latin rectangle and the treatments were 1) corn-soybean meal diet adequate in Ca and P (0.5% Ca, 0.19% available P [aP]), 2) corn-soybean meal diet with reduced Ca and P (0.4% Ca, 0.09% aP), 3) Diet 1 with 500 phytase units/kg, or 4) Diet 2 with 500 phytase units/kg. Pigs were fed twice daily to a total daily energy intake of 2.6 x maintenance (106 kcal of ME/kg of BW(0.75)). For each ileal digesta sample, digesta samples were collected for two 24-h periods and combined for each pig. The combination of supplementing with phytase and decreasing the concentration of dietary Ca and P increased average ileal AA (P < 0.02), starch (P < 0.02), GE (P < 0.04), and DM (P < 0.03) digestibilities. In Exp. 2, a feeding challenge was conducted with barrows (eight per treatment; average BW of 53 kg). The treatments consisted of a corn-soybean meal diet or corn-soybean meal diet + 500 phytase units per kilogram of diet. In the diet with no phytase, Ca and aP were at 0.50% and 0.19%, respectively, and, in the diet with phytase, Ca and aP were each decreased by 0.12%. A catheter was surgically inserted into the anterior vena cava of each pig 6 d before the start of the feeding challenge. The barrows were penned individually, and the diets were fed for 3 d before the challenge. The pigs were held without feed for 16 h, and blood samples were obtained at -60, -30, and 0 min before the pigs were fed (2% of BW). Blood samples were then collected at 10, 20, 30, 40, 50, 60, 75, 90, 105, 120, 150, 180, 210, 240, 270, and 300 min after feeding. Glucose area under the response curve and plasma glucose, insulin, urea N, and total alpha-amino N concentrations were increased (P < 0.05) in pigs fed the diet with reduced Ca and P and the phytase addition. Area under the response curve for insulin, urea N, and total alpha-amino N; insulin:glucose; and plasma NEFA concentration, clearance, and half-life were not affected by diet. In conclusion, the combination of Ca and P reduction and phytase addition increased nutrient and energy digestibility in diets for pigs and increased plasma concentrations of glucose, insulin, urea N, and alpha-amino N.


Assuntos
6-Fitase/administração & dosagem , Cálcio da Dieta/administração & dosagem , Digestão/efeitos dos fármacos , Fósforo na Dieta/administração & dosagem , Suínos/metabolismo , 6-Fitase/metabolismo , Aminoácidos/sangue , Aminoácidos/metabolismo , Ração Animal , Animais , Área Sob a Curva , Glicemia/análise , Nitrogênio da Ureia Sanguínea , Cálcio da Dieta/metabolismo , Relação Dose-Resposta a Droga , Metabolismo Energético/fisiologia , Ácidos Graxos não Esterificados/sangue , Íleo/metabolismo , Insulina/sangue , Masculino , Fósforo na Dieta/metabolismo , Distribuição Aleatória , Suínos/sangue , Suínos/crescimento & desenvolvimento
17.
Annu Rev Genet ; 37: 513-43, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14616072

RESUMO

Cyanobacteria such as Synechococcus elongatus PCC 7942 exhibit 24-h rhythms of gene expression that are controlled by an endogenous circadian clock that is mechanistically distinct from those described for diverse eukaryotes. Genetic and biochemical experiments over the past decade have identified key components of the circadian oscillator, input pathways that synchronize the clock with the daily environment, and output pathways that relay temporal information to downstream genes. The mechanism of the cyanobacterial circadian clock that is emerging is based principally on the assembly and disassembly of a large complex at whose heart are the proteins KaiA, KaiB, and KaiC. Signal transduction pathways that feed into and out of the clock employ protein domains that are similar to those in two-component regulatory systems of bacteria.


Assuntos
Ritmo Circadiano/fisiologia , Cianobactérias/fisiologia , Ritmo Circadiano/genética , Cianobactérias/genética , Regulação Bacteriana da Expressão Gênica/fisiologia , Fatores de Tempo , Transcrição Gênica/fisiologia
20.
Med Phys ; 28(6): 1006-9, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11439469

RESUMO

A computer controlled multileaf collimator (MLC) is being designed to replace the multirod collimator (MRC) at present used to shape the d(48.5) + Be neutron beam from the Harper Hospital superconducting cyclotron. The computer controlled MLC will improve efficiency and allow for the future development of intensity modulated radiation therapy with neutrons. The existing MRC uses tungsten rods, while the new MLC will use steel as the leaf material. In the current study the attenuation and activation characteristics of steel are compared with those of tungsten to ensure that (a) the attenuation achieved in the MLC is at least equivalent to that of the existing MRC, and (b) that the activation of the steel will not result in a significant change in the activation levels within the treatment room. The latter point is important since personnel exposure (particularly to the radiation therapy technologists) from induced radioactivity must be minimized. Measurement of the neutron beam attenuation in a broad beam geometry showed that a 30 cm thick steel leaf yielded 2.5% transmission. This compared favorably with the 4% transmission obtained with the existing MRC. Irradiation of steel and tungsten samples at different depths in a 30 cm steel block indicated that the activation of steel should be no worse than that of tungsten.


Assuntos
Nêutrons Rápidos/uso terapêutico , Radioterapia Conformacional/instrumentação , Aço , Tungstênio , Fenômenos Biofísicos , Biofísica , Ciclotrons , Humanos , Planejamento da Radioterapia Assistida por Computador/estatística & dados numéricos , Radioterapia Conformacional/estatística & dados numéricos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...