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1.
Animal ; 18(3): 101084, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38367312

RESUMO

Procedures such as transport and marketing can subject animals to water and feed deprivation and impair animal health and performance. Maintaining the mineral status of animals under these conditions can bring benefits to health and performance. The use of hydroxychloride mineral sources can improve mineral status, nutrient digestibility and performance. Two studies were conducted to investigate how the supplementation of 02 trace mineral sources of Cu and Zn and 48-hour water/feed deprivation would affect the performance and metabolism of grass-fed beef cattle. In the first study, 20 castrated and rumen-canulated Nellore steers (BW = 350 ±â€¯132 kg; 20 m) were distributed in individual pens, in a 2 × 2 factorial arrangement: supplemental Cu and Zn sources from inorganic vs hydroxychloride (HTM) and 48-hours deprivation (WFD) vs unrestricted (WFU) access to water and feed. The 57d of study was divided into two periods: (1) Adaptation from -21d to -1d and (2) evaluation from 0d to 36d. Interaction between deprivation × period was detected (P < 0.05) for digestibility of DM (DMD), organic matter (OMD), neutral detergent fiber (NDFD), and acid detergent fiber (ADFD). Deprivation increased DMD, OMD, NDFD, and ADFD immediately after the deprivation period (3-5d), but impaired digestibility at longer periods such as 11-13d and 32-34d. DM (DMI) and nutrient intake (P = 0.075), as well as NDFD were higher in HTM. Several ruminal parameters were affected by deprivation: short-chain fatty acids concentration decreased, while rumen pH increased (deprivation × time; P < 0.05); decreased propionate, butyrate and increased isobutyrate, isovalerate, and valerate in WFD (deprivation × time; P < 0.05), respectively. In the second study, eighty-four intact Nellore males (BW = 260 ±â€¯35 kg) were blocked by BW and randomly assigned to Urochloa brizantha cv. Marandu paddocks for 131d in a 2 × 2 factorial arrangement. Liver Cu was higher in WFU/HTM animals (mineral × deprivation; P < 0.05). Interaction between deprivation × period (P < 0.05) was detected for BW and average daily gain (ADG). On 2d and 12d after deprivation, WFD increased ADG and recovered the BW lost. In conclusion, water and feed deprivation imposed in these trials were able to impact several nutrient digestibility and ruminal fermentation parameters in short- and long-term. Performance was not affected by the studied factors. Furthermore, supplementation with sources of Cu and Zn hydroxychloride increased Cu in the liver and tended to increase DMI and NDFD.


Assuntos
Cobre , Zinco , Masculino , Bovinos , Animais , Suplementos Nutricionais , Dieta/veterinária , Água/metabolismo , Detergentes/metabolismo , Digestão , Minerais/metabolismo , Fermentação , Ração Animal/análise , Rúmen/metabolismo
2.
Animal ; 18(9): 101260, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39116470

RESUMO

In Brazil, heifers typically calve at 36-48 months. Due to the high demand for meat and the need to reduce slaughter age, high supplementation has become commonly used in beef cattle farming. However, the literature remains scarce on studies that explore the impact of grazing management during the background phase on the productivity and reproductive efficiency of young Nellore heifers. This study aimed to evaluate the effects of two-herbage allowances (HA) on forage characteristics, performance, physiology and reproductive parameters of replacement Nellore heifers. Ninety weaned heifers [169 ± 19 kg of shrunk body weight (SBW); 210 ± 28 days of age] were blocked by initial BW and randomly assigned to receive different HA: (1) High herbage allowance (HHA: 7.2 kg DM/kg BW) and (2) Low herbage allowance (LHA: 3.3 kg DM/kg BW); and divided into six paddocks, totaling 12 paddocks. The experimental period was divided into the growing phase (D173) and the reproductive season (D83). Continuous stocking with a variable stocking rate was used. The supplement was provided daily with expected intake of around 10 g/kg of BW. The HHA pasture showed greater values of canopy height, greater HA, and lower values of CP and CP: in vitro digestible DM ratio than the LHA pasture over the days of the study (P ≤ 0.05). Herbage mass and the green stem proportion were lower in LHA pasture (P < 0.01), while the green leaf (g/kg DM) and senescent stem proportions (g/kg DM) were higher (P = 0.080) when compared to HHA pasture. Heifers maintained on HHA pasture had a higher average daily gain (P < 0.01), forage intake (P < 0.003), higher SBW (P < 0.01), Longissimus area (P < 0.01), and 12th-rib fat thickness (P < 0.01) than those kept in the LHA pasture. The proportion of heifers that reached the weight at maturity on D173 (P = 0.027) and the proportion of pubertal pregnancy heifers (P = 0.042) were greatest in the HHA treatment. The blood urea nitrogen (P = 0.002) was higher in heifers maintained in the LHA pasture. Heifers maintained in HHA pasture showed higher values of relative abundance of mRNA for UGT1A6 (P = 0.004) and IGFBP3 (P = 0.072). The use of HHA criteria increased forage intake, body gain, and carcass attributes of animals, which led to better reproductive performance of Nellore heifers.


Assuntos
Ração Animal , Dieta , Suplementos Nutricionais , Reprodução , Animais , Bovinos/fisiologia , Feminino , Ração Animal/análise , Suplementos Nutricionais/análise , Reprodução/efeitos dos fármacos , Brasil , Dieta/veterinária , Criação de Animais Domésticos/métodos , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Distribuição Aleatória
3.
Pediatr Surg Int ; 28(1): 75-8, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21681581

RESUMO

Bronchial carcinoid tumors are the most common primary pulmonary neoplasm in the pediatric population. The widely accepted treatment for carcinoid tumors is surgical, specifically aiming at being as much as conservative on lung parenchyma, while the entire tumor is resected. A brief case is described, highlighting the importance and advantages of a surgical and endoscopic combined approach.


Assuntos
Neoplasias Brônquicas/cirurgia , Broncoscopia/métodos , Tumor Carcinoide/cirurgia , Pneumonectomia/métodos , Neoplasias Brônquicas/diagnóstico , Tumor Carcinoide/diagnóstico , Criança , Diagnóstico Diferencial , Feminino , Seguimentos , Humanos , Período Intraoperatório , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X
4.
IEEE Trans Neural Netw ; 9(6): 1483-94, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-18255825

RESUMO

A variety of computational tasks in early vision can be formulated through lattice networks. The cooperative action of these networks depends on the topology of interconnections, both feedforward and recurrent ones. This paper shows that it is possible to consider a distinct general architectural solution for all recurrent computations of any given order. The Gabor-like impulse response of a second-order network is analyzed in detail, pointing out how a near-optimal filtering behavior in space and frequency domains can be achieved through excitatory/inhibitory interactions without impairing the stability of the system. These architectures can be mapped, very efficiently at transistor level, on very large scale integration (VLSI) structures operating as analog perceptual engines. The problem of hardware implementation of early vision tasks can, indeed, be tackled by combining these perceptual agents through suitable weighted sums. A 17-node analog current-mode VLSI circuit has been implemented on a CMOS 2 microm, NWELL, single-poly, and double-metal technology, to demonstrate the feasibility of the approach. Applications of the perceptual engine to various machine vision algorithms are proposed.

5.
Eur J Pediatr Surg ; 4(2): 67-9, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8025098

RESUMO

The final aim of the treatment of oesophageal atresia is to restore continuity without the interposition of intestinal segments. The authors present the results of a new diagnostic method combining endoscopy and radiology to evaluate the development of pouches in oesophageal atresia. This new method has been successfully adopted in four patients aged between 4 and 8 months, three with type I and one with type III complicated atresia. Direct end-to-end anastomosis was performed in all patients. We think this method can be easily applied and is a suitable diagnostic examination in all cases in which surgical strategy aims at restoring oesophageal continuity by means of direct anastomosis.


Assuntos
Atresia Esofágica/diagnóstico , Anastomose Cirúrgica , Atresia Esofágica/diagnóstico por imagem , Atresia Esofágica/cirurgia , Esofagoscopia , Esôfago/cirurgia , Humanos , Lactente , Radiografia
6.
Eur J Pediatr Surg ; 4(5): 287-92, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7857885

RESUMO

The authors present a review of 431 children biopsied and studied with the following histochemical and immunohistochemical techniques: 1) acetylcholinesterase activity; 2) alphanaphthylesterase activity; 3) S-100 protein immunohistochemical technique; 4) glyoxylic acid method. Two hundred forty-eight patients of our series presented different forms of dysganglionosis, 12 of them (4.8%) presenting neuronal intestinal dysplasia type B. In 7 cases, NID type B was diffuse, whereas in 5 recto-colonic NID type B was confined to the splenic flexure. Male:female ratio was 9:3. Familial recurrence was present in 2 of the 12 cases of our series, affected by severe neuronal intestinal dysplasia extended to the small intestine, associated with intestinal malrotation and short bowel syndrome. Four of the 7 cases of diffuse NID type B and 2 of the 5 cases of rectocolonic NID type B were surgically treated. Three patients with diffuse NID died from sepsis within the 2nd year of life. This study confirms that NID type B is a form of dysganglionosis which can be diagnosed in a Mediterranean country if histochemical techniques are applied in the study of a large series of constipated and pseudo-Hirschsprung patients. From a pathogenetic point of view, the authors compared the histochemical findings of biopsies from their series of NID patients with those of recto-colonic biopsies from patients with MEN II B syndrome. The similarity of GI symptoms in MEN II B and NID pediatric patients suggests that the two disorders could be the result of mutations affecting the same domain of the RET proto-oncogene.


Assuntos
Doença de Hirschsprung/patologia , Plexo Mientérico/patologia , Plexo Submucoso/patologia , Acetilcolinesterase/metabolismo , Biomarcadores , Biópsia , Criança , Pré-Escolar , Colo/inervação , Colo/cirurgia , Feminino , Doença de Hirschsprung/classificação , Doença de Hirschsprung/genética , Doença de Hirschsprung/cirurgia , Humanos , Imuno-Histoquímica , Lactente , Itália , Masculino , Naftol AS D Esterase/metabolismo , Proto-Oncogene Mas , Reto/inervação , Reto/cirurgia , Proteínas S100/metabolismo
7.
Eur J Pediatr Surg ; 3(5): 306-8, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8292586

RESUMO

The authors report a case of leiomyosarcoma of the cecum and review all the Italian reports of mesenchymal neoplasms registered in the RMS-Italy register. They emphasize the extreme rarity of intestinal leiomyosarcoma, especially with colon involvement: their case appears to be the only one registered in Italy in the last 12 years.


Assuntos
Neoplasias do Ceco/cirurgia , Leiomiossarcoma/cirurgia , Neoplasias do Ceco/diagnóstico , Neoplasias do Ceco/patologia , Ceco/patologia , Criança , Colectomia , Feminino , Humanos , Leiomiossarcoma/diagnóstico , Leiomiossarcoma/patologia , Mitose/fisiologia , Reoperação
8.
Minerva Chir ; 48(9): 485-9, 1993 May 15.
Artigo em Italiano | MEDLINE | ID: mdl-8355878

RESUMO

Necrotizing enterocolitis (NEC) is an important cause of neonatal morbidity and mortality. During the last few years, there was an increase in the incidence of this disease, associated with a better knowledge of NEC, and an increase in survival rate, associated with the development, even from a technological point of view, of neonatal intensive care units. In this study, the authors first perform the diagnostic procedures and describe the anatomical and clinical characteristics of NEC, then evaluate by standard criteria a series of patients observed during the last 5 years, revising the various surgical treatments adopted and the results obtained.


Assuntos
Enterocolite Pseudomembranosa/diagnóstico , Colo/patologia , Colo/cirurgia , Colostomia , Terapia Combinada , Enterocolite Pseudomembranosa/patologia , Enterocolite Pseudomembranosa/cirurgia , Humanos , Ileostomia , Íleo/patologia , Íleo/cirurgia , Recém-Nascido
14.
Neural Comput ; 9(3): 525-31, 1997 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-9097472

RESUMO

The spatial organization of cortical axon and dendritic fields could be an interesting structural paradigm to obtain a functional specificity without postulating highly specific feedforward connections. In this article, we investigate the functional implications of recurrent intracortical inhibition when it occurs through clustered medium-range interconnection schemes (Wörgötter & Koch, 1991; Somogyi, 1989; Kritzer, Cowey, & Somogyi, 1992). Moreover, the interaction between the inhibitory schemes and visual orientation maps is explored. Assuming linearity, we show that clustered inhibitory mechanisms can trigger a propagation process that allows the development of extra (i.e., induced) interactions among the cortical sites involved in the recurrent loops. In addition, we point out how these interactions functionally modify the response of cortical simple cells and yield to highly structured Gabor-like receptive fields. This study should be considered not as a realistic biological model of the primary visual cortex but as an attempt to explain possible computational principles related to intracortical connectivity and to the underlying single-cell properties.


Assuntos
Córtex Cerebral/fisiologia , Redes Neurais de Computação , Neurônios/fisiologia , Córtex Cerebral/citologia , Modelos Lineares , Modelos Neurológicos , Vias Neurais/fisiologia , Orientação/fisiologia , Córtex Visual/fisiologia , Campos Visuais/fisiologia
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