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Avaliação da atividade gastroprotetora da fucana livre e nanoencapsulada em lipossomasMELO, Audenes de Oliveira 31 July 2013 (has links)
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Previous issue date: 2013-07-31 / CAPES / O objetivo deste trabalho foi encapsular a fucana (Sargassum cymosum), em
lipossomas e avaliar a atividade gastroprotetora, tanto na sua forma livre, como
encapsulada. Os lipossomas foram obtidos e caracterizados por testes físico-químicos
e de estabilidade. A atividade gastroprotetora in vivo foi realizada utilizando ratos
Wistar, pré-tratados durante 14 dias com a fucana livre (Fuc), nanoencapsulada (Lipo-
Fuc), e com os controles positivo (sem úlcera) e negativo (com úlcera e sem
tratamento), por via oral. Após jejum (48 horas), a úlcera foi induzida com ácido
acetilsalisílico (200 mg/Kg), o estômago e o duodeno foram removidos para análises
histológicas avaliando-se a área com muco, espessura do epitélio glandular e
vilosidades intestinais. Os resultados foram analisados pelos testes t-Student e
Kruskal-Wallis. Lipossomas contendo fucana foram obtidos apresentando tamanho
médio de partícula de 125,9 ± 1,2 nm, com índice de polidispersão 0,39 ± 0,02 e pH
6,89 ± 0,05 e carga positiva, permanecendo estáveis por 30 dias. Em relação à área
de muco no estômago, os resultados mostraram que, no grupo pré-tratado com a Fuc,
os animais permaneceram com média da área de muco semelhante ao grupo que não
foi realizada indução da úlcera (7,5 ± 4,5 μm2 e 9 ± 6,7 μm2, respectivamente). Por
outro lado, a fucana encapsulada exibiu uma área (2,6 ± 1,6 μm2) similar ao grupo com
úlcera não tratada (3,5 ± μm2), sugerindo que o composto possivelmente não foi
liberado a partir das vesículas no estômago, não promovendo, portanto nenhuma
ação. No estudo dos danos epiteliais o grupo da Fuc apresentou valores superiores
aos demais grupos tratados revelando novamente sua ação gastroprotetora. As
análises no duodeno revelaram uma área média de 7,52 ± 2,42 μm2 para um epitélio
normal (sem úlcera), 6,00 ± 3,17 μm2 para o epitélio com úlcera sem tratamento, 6,43
± 1,82 μm2 e 6,62 ± 1,31 μm2 para epitélio com úlcera após tratamento com a fucana
livre e encapsulada, respectivamente. Neste local, pode ser observado valor maior
para tratamento com a Lipo-Fuc quando comparado ao obtido na Fuc, sugerindo que
houve liberação da fucana a partir dos lipossomas, ao contrário do encontrado no
estômago. Em relação à análise das vilosidades intestinais a fucana encapsulada
exerceu uma atividade citoprotetora com uma extensão média de 395,53 ± 118,64 μm,
inferior ao grupo com o composto livre, mas superior ao grupo referente ao controle
negativo, o qual apresentou uma área de 314,10 ± 59,71 μm. Os resultados revelaram
ação gastroprotetora da fucana (Sargassum cymosum), até então nunca estudada
fornecendo subsídios para novas pesquisas utilizando esta molécula.
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The pharmacokinetics of ranitidine in patients with chronic duodenal ulceration and in patients with chronic renal failureMcFadyen, Margaret Lynn January 1981 (has links)
The pharmacokinetics of orally administered ranitidine were studied in 10 patients with endoscopically proved duodenal ulceration after a single 150 mg dose and after 4 weeks 1 ranitidine treatment (150 mg twice daily), at which time there was endoscopic evidence of complete ulcer healing. After a single dose the median elimination half-life was 135 minutes and the median area under the curve (AUC) was l 844 ng/ml.hr. Although the maximum concentration after a single dose (Cmax = 365 ng/ml) was significantly different from that after continuous treatment (Cmax = 562 ng/ml) (p <0,05) there was no significant difference between the minimum concentrations at 12 hours post-dosing (Cmin = 35 ng/ml and 30 ng/ml respectively) and the median half-lives were identical. No accumulation of ranitidine occurred in these patients after 4 weeks' chronic ranitidine treatment. Five patients received 20 mg ranitidine intravenously. The apparent volume of distribution of the central compartment ranged from 10,5 to 28,4 1 while the elimination rate constant β range from 0,34 to 0,78 h⁻¹ with the t½ ranging from 53 to 122 minutes. The mean oral bioavailability was 51%. The pharmacokinetics of ranitidine were studied in a further 7 patients with chronic duodenal ulceration who showed endoscopic evidence of unhealed ulcers after at least 8 weeks' treatment with ranitidine. There were no significant differences in any of the pharmacokinetic parameters when these patients were compared with the 10 responders above after multiple-dosage except that the disposition rate constant was smaller in non-responders (0,24 h⁻¹ compared with 0,31 h⁻¹, p <0,002). Two patients did, however, have very low plasma concentrations with above average basal and maximal acid output which may have contributed to the lack of response to ranitidine treatment. Single- and multiple-dose pharmacokinetic studies of oral ranitidine were carried out in 6 patients with chronic renal failure (RF) (creatinine clearance <25 ml/min) and compared with those obtained for the 10 patients with chronic duodenal ulceration with normal renal function (creatinine clearance >65 ml/min). There appeared to be no significant differences in absorption rate or amount absorbed but the median elimination rate constant was significantly reduced from 0,31 h⁻¹ in controls to 0,14 h⁻¹ in RF (p <0,002) resulting in a two-fold increase in t½ (312 minutes) after a single dose. Cmax did not differ significantly although Cmin and AUC were significantly larger in RF patients (both p <0,002). It is suggested that the dosage of ranitidine be reduced from 150 mg to 75 mg twice daily in severe renal failure although it was not possible to relate half-life, elimination rate constant or AUC directly to creatinine clearance.
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Systematic Review with Meta-Analysis: Endoscopic and Surgical Resection for Ampullary LesionsHeise, Christian, Abou Ali, Einas, Hasenclever, Dirk, Auriemma, Francesco, Gulla, Aiste, Regner, Sara, Gaujoux, Sébastien, Hollenbach, Marcus 20 April 2023 (has links)
Ampullary lesions (ALs) can be treated by endoscopic (EA) or surgical ampullectomy (SA) or pancreaticoduodenectomy (PD). However, EA carries significant risk of incomplete resection while surgical interventions can lead to substantial morbidity. We performed a systematic review and meta-analysis for R0, adverse-events (AEs) and recurrence between EA, SA and PD. Electronic databases were searched from 1990 to 2018. Outcomes were calculated as pooled means using fixed and random-effects models and the Freeman-Tukey-Double-Arcsine-Proportion-model. We identified 59 independent studies. The pooled R0 rate was 76.6% (71.8–81.4%, I2 = 91.38%) for EA, 96.4% (93.6–99.2%, I2 = 37.8%) for SA and 98.9% (98.0–99.7%, I2 = 0%) for PD. AEs were 24.7% (19.8–29.6%, I2 = 86.4%), 28.3% (19.0–37.7%, I2 = 76.8%) and 44.7% (37.9–51.4%, I2 = 0%), respectively. Recurrences were registered in 13.0% (10.2–15.6%, I2 = 91.3%), 9.4% (4.8–14%, I2 = 57.3%) and 14.2% (9.5–18.9%, I2 = 0%). Differences between proportions were significant in R0 for EA compared to SA (p = 0.007) and PD (p = 0.022). AEs were statistically different only between EA and PD (p = 0.049) and recurrence showed no significance for EA/SA or EA/PD. Our data indicate an increased rate of complete resection in surgical interventions accompanied with a higher risk of complications. However, studies showed various sources of bias, limited quality of data and a significant heterogeneity, particularly in EA studies.
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Early detection of duodenal cancer by upper gastrointestinal-endoscopy in Lynch syndromeVangala, Deepak B., Ladigan-Badura, Swetlana, Engel, Christoph, Hüneburg, Robert, Perne, Claudia, Buksch, Karolin, Nattermann, Jacob, Steinke-Lange, Verena, Rahner, Nils, Weitz, Jürgen, Kloor, Matthias, Tomann, Judith, Canbay, Ali, Nguyen, Huu-Phuc, Strassburg, Christian, Möslein, Gabriele, Morak, Monika, Holinski-Feder, Elke, Büttner, Reinhard, Aretz, Stefan, Löffler, Markus, Schmiegel, Wolff, Pox, Christian, Schulmann, Karsten, for Familial Intestinal Cancer, German Consortium 05 June 2023 (has links)
Small bowel cancer (SBC) is the malignancy with the highest standardized incidence ratio in Lynch syndrome (LS) patients. Of all SBCs, about 50% are duodenal cancers (DCs), therefore being accessible by esophago-gastro-duodenoscopy (EGD) for surveillance. We asked whether early detection of DC is possible for LS patients undergoing surveillance by EGD and if surveillance should be limited to specific subgroups. Data for LS patients with DC were retrieved from the registry of the German Consortium for Familial Intestinal Cancer. Patients undergoing active surveillance by EGDs (surveillance group) were compared to those who did not (nonsurveillance group) regarding tumor stage at diagnosis. Union for International Cancer Control stages I-IIA were defined as early stage disease and IIB-IV as advanced stage disease. Statistical analysis was performed using Fisher's exact test. Among 2015 patients with pathogenic variants in any mismatch-repair-gene, 47 patients with 49 DCs were identified. In 10% of cases, patients were under 35 years at diagnosis; family and personal tumor history did not correlate with DC diagnosis. Pathogenic germline variants in MSH6, PMS2 or EPCAM were present in 10% of patients. Statistical analysis could be performed on 13 DC patients in the surveillance group and 14 in the nonsurveillance group. Early detection was possible for 71% of patients in the surveillance group and 29% of patients in the nonsurveillance group (P = .021). Early detection of DC by EGD in LS patients is feasible regardless of family history, mutational status and should start no later than 25 years of age.
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Mechanisms for the recovery of type 2 diabetes mellitus following bariatric surgeryGamby, Danielle Nicole 12 March 2016 (has links)
Studies have shown that following bariatric surgery, there is an almost immediate reversal of type 2 diabetes. However, there still remains questions as to why this occurs and what possible explanations there may be.
This paper aims to focus on several studies that have found a reversal of diabetes in obese patients who have undergone bariatric surgery. Furthermore, it explores several possibilities for the reasons behind this reversal including the role of AMP-activated protein kinase, the incretins gastric inhibitory peptide and glucagon-like peptide-1, and also looks at genetics.
Bariatric surgery and a description of certain mechanisms are first described for an understanding. Following is a literature review of published studies on bariatric surgery, the reversal of diabetes following the procedure, and roles of AMPK and incretins.
Because of the possibility that reduced caloric intake may not be the major factor in the diabetic reversal, it is suggested that further research be done on obese and normal weight patients and observe the levels of the mentioned mechanisms and also various genes to see if they offer a more thorough explanation.
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Double Bubble Trouble: Misdirection in the Diagnosis of Pyloric StenosisHelmey, Nancy, Schweitzer, John 25 April 2023 (has links) (PDF)
Infantile hypertrophic pyloric stenosis (IHPS) is a disorder characterized by hypertrophy of the pylorus causing obstruction of the gastric outlet. IHPS occurs in 1 to 3.5 per 1000 live births and normally develops between weeks 3 to 5 of age. Patients commonly present forceful, projectile, nonbilious vomiting. The diagnosis is confirmed with ultrasound in which pyloric muscle thickness (PMT) and pyloric canal length (PCL) are measured as less than or equal to 3.0 mm and 14.5 mm, respectively. Definitive treatment is surgicalpyloromyotomy. Similarly, duodenal atresia can cause projectile, nonbilious vomiting. However, it typically presents within the first 24 to 38 hours of birth. If not diagnosed antenatally, then the classic “double bubble sign” on abdominal x-ray or upper GI series is pathognomonic.
In this case study, we discuss a case in which diagnostic imaging leads to the misdiagnosis of a patient presenting with projectile vomiting. Initial presentation, differential diagnosis, and hospital workup will be discussed. We present this case study to raise awareness of the possible misdiagnosis of a common childhood illness due to aberrant radiographic presentation.
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Self-expandable metal stent placement for the palliation of malignant gastroduodenal obstruction: experience in a large, single, UK centreLowe, A.S., Beckett, C.G., Jowett, S., May, J., Stephenson, S., Scally, Andy J., Tam, E., Kay, C.L. January 2007 (has links)
No / To assess the technical success rate, and evaluate the clinical outcome, length of hospital stay, and cost of palliative gastro-duodenal stenting in a single-centre.
Materials and methods
Eight-seven patients referred for insertion of a gastroduodenal stent between April 1999 and April 2004 were recruited to a non-randomized, before and after intervention study performed in a single centre. Demographic data, diagnosis and symptoms along with clinical and technical outcomes were recorded.
Results
The technical success rate was 84/87 (96.6%), with inability to traverse the stricture in three patients. No immediate complications were demonstrated. There was marked improvement after stent placement with resolution of symptoms and commencement of dietary intake in 76 patients (87%). Stenting resulted in improved quality of life as reflected by an increase in Karnofsky score from 44/100, to 63/100 post-procedure. Late complications included perforation (n=1), migration (n=1) and stent occlusions due to tumour ingrowth/overgrowth (n=7; mean 165 days). Mean survival was 107 days (range 0¿411 days). Median hospital stay post-stent placement was 5.5 days, (range 1¿55 days) with a majority of patients (75%) discharged home. The mean cost of each treatment episode was £4146 ($7132 $US, ¿6,028 EUROS).
Conclusion
The present series confirms that combined endoscopic and radiological gastroduodenal stenting is a highly favourable treatment for patients with inoperable malignant gastric outlet obstruction. The results suggest that this minimally invasive procedure has a very high technical success rate, whilst at the same time providing excellent palliation of symptoms with improved quality of life in the majority of patients.
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Métodos de pesquisa em nutrição de ruminantes: indicadores de índice fecal, n-alcanos e fibra em detergente ácido para estimativa do consumo e/ou fluxo intestinal de nutrientes / Research methods in ruminants nutrition: fecal index, n-alkanes and acid detergent fiber to estimate intake and intestinal flow of nutrientsCollet, Silvana Giacomini 11 November 2011 (has links)
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Previous issue date: 2011-11-11 / The aim of this study was to validate the use of n-alkanes C31, C32 and C33 on estimates of intake and digestibility and assess the accuracy of the use of indicators and acid detergent fiber (ADF), compared to the lignin in the studies of duodenal flow of nutrients. In addition, was to studied the use of indicators of fecal content in the estimation of digestibility and forage intake in lambs receiving ryegrass green. Two assays were conducted digestibility "in vivo" with 16 days each (11 for adaptation and 5 collection). The treatments consisted of diets composed by Italian ryegrass (Lolium multiflorum Lam.), in two successive cycles of grazing (28 and 35 days regrowth). The n-alkane C33 showed fecal recovery close to 1,0 in both tests and was more accurate in predicting the digestibility of C31. The intestinal flows of dry matter (DM) estimated from the C31, FDA or lignin were similar. In addition, the flow estimates obtained by internal ADF and lignin markers proved closely associated (linear coefficient = 1,016, r2 = 0,809). In local validation of the use of n-alkanes to estimate the consumption pair C33: C32 showed better relationship with the observed dry matter intake, since it held the correction for recovery rate of fecal C32. For the study of fecal indicators index the best estimates of consumption of organic matter (IOM) were obtained when using the amounts excreted nitrogen (g / day) and neutral detergent fiber (NDF, g / day) associated with the content forage NDF (r² = 0,78, rsd = 0,095). In conclusion, estimates of consumption and / or digestibility using the technique of n-alkanes should be preceded by local validation tests, studies of the intestinal flow of nutrients the FDA can be used instead of the lignin and estimates of forage intake in sheep may be made depending on the amount of nitrogen excreted per day and NDF / Os objetivos deste trabalho foram validar o uso dos n-alcanos C31, C32 e C33 em estimativas de consumo e digestibilidade e avaliar a exatidão do uso destes indicadores e da fibra em detergente ácido (FDA), em comparação à lignina, nos estudos de fluxo duodenal de nutrientes. Além disso, foi estudado o uso de indicadores de índice fecal na estimativa da digestibilidade e do consumo de forragem em ovinos recebendo azevém anual verde. Foram conduzidos dois ensaios de digestibilidade in vivo com 16 dias de duração cada (11 de adaptação e 5 de coleta). Os animais utilizados foram oito ovinos machos, castrados, mantidos em gaiolas de metabolismo. A dieta fornecida foi composta exclusivamente de azevém anual (Lolium multiflorum Lam.) verde em dois ciclos de desenvolvimento (28 e 35 dias de rebrote). O n-alcano C33 apresentou recuperação fecal próxima de 1,0 em ambos os ensaios e se mostrou mais exato na predição da digestibilidade aparente que o C31. Os fluxos intestinais de matéria seca (MS) estimados a partir do C31, FDA ou lignina foram semelhantes. Além disso, as estimativas de fluxo obtidas pelos marcadores internos FDA e lignina se mostraram estreitamente associadas (coeficiente linear = 1,016; r2 = 0,809). Na validação local da utilização dos n-alcanos para estimativa do consumo o par C33:C32 mostrou melhor relação com o consumo de matéria seca observado, desde que realizada a correção pra taxa de recuperação fecal do C32. Para o estudo com indicadores de índices fecais as melhores estimativas do consumo de matéria orgânica (CMO) foram obtidas quando se utilizou as quantidades excretadas de nitrogênio (g/dia) e fibra em detergente neutro (FDN, g/dia) associados ao teor de FDN na forragem (r² = 0,78; dpr = 0,095). Em conclusão, estimativas do consumo e/ou digestibilidade aparente utilizando a técnica dos n-alcanos devem ser precedidas de ensaios de validação local; nos estudos do fluxo intestinal de nutrientes o FDA pode ser utilizado em substituição a lignina e estimativas do consumo de forragem em ovinos podem ser efetuadas em função da quantidade de nitrogênio e FDN excretados por dia
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Biodistribui??o do pertecnetato de s?dio ap?s cirurgia do Switch DuodenalAra?jo Filho, Irami 15 August 2007 (has links)
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Previous issue date: 2007-08-15 / The biliopancretic diversion with duodenal switch is one of the mixing techniques used in the treatment of morbid obesity. The duodenal switch reduces the stomach capacity and leaves only 50-100 cm of small intestine for nutrition and absorption. The surgery produces hormonal, structural and biochemical changes, which can influence on the result of scintigraphic examinations in operated patients. With the objective of evaluate the postoperative biodistribution of sodium pertechnetate (Na99mTcO4) in brain, thyroid, heart, lung, liver, spleen, kidney, stomach, duodenum, pancreas, small intestine, bladder, muscle and bone of Wistar rats. The rats were randomly allocated into 3 groups of 7 rats each: the duodenal switch group (DS), the control group (C) and the sham group (S). They were operated under anesthesia and aseptic technique. In the tenth postoperative day, 0.1mL of sodium pertechnetate was injected via orbital plexus. After 30 min the animals were killed with overdose of anesthetic and samples of liver, spleen, pancreas, stomach, duodenum, small intestine, thyroid, lung, heart, kidney, bladder, muscle, bone and brain were harvested, washed with saline and weighed. The detention of radioactivity was made using the automatic Gamma Counter Wizard, PerkinElmer and the percentage of activity per gram of tissue (%ATI/g) was calculated. There was no early or late mortality in either rats groups. The values of percent radioactivity per gram of tissue (%ATI/g), showed no significant difference in liver, stomach, small bowel, duodenum, kidney, heart, bladder, bone and brain, when compared the DS rats with sham and controls rats. A postoperative significant increase in mean %ATI/g levels was observed in spleen, pancreas and muscle in group DS rats, as compared to group S and C rats (p<0.05). In the lung there was an increase and in thyroid a decrease in mean %ATI/g of DS rats, when compared to sham rats (p>0.05). In conclusion, the biliopancreatic diversion with duodenal switch in rats modified the biodistribution of sodium pertechnetate in thyroid, lung, pancreas, spleen and muscle. The study had the participation of the departments and laboratories researches, as Nucleus of Experimental Surgery, Department of Surgery, Laboratory of Radiobiology, Department of Pathology and Service of Nuclear Medicine, certifying the character of a multidisciplinary research / A cirurgia do desvio biliopancre?tico ? uma das t?cnicas mistas utilizada no tratamento da obesidade m?rbida. O Switch duodenal reduz o est?mago a ? de sua capacidade e deixa apenas 50-100 cm de intestino delgado para nutri??o e absor??o. Isso leva a altera??es estruturais, hormonais e bioqu?micas que podem influenciar no resultado de exames cintilogr?ficos de pacientes operados. Com o objetivo de avaliar a biodistribui??o p?s-operat?ria do pertecnetato de s?dio (Na99mTcO4) em ?rg?os de diversos sistemas como c?rebro, tire?ide, cora??o, pulm?o, f?gado, ba?o, rim, est?mago, duodeno, p?ncreas, intestino delgado, bexiga, m?sculo e f?mur de ratos Wistar submetidos ? t?cnica do switch duodenal, foram utilizados ratos com 3 meses de idade alocados aleatoriamente em: grupo tratado, submetido ? cirurgia de desvio biliopancre?tico, t?cnica do switch duodenal (SD), o grupo controle (C) e o grupo submetido a uma simula??o de cirurgia, denominado sham (S). No d?cimo dia de p?s-operat?rio, 0,1 mL do pertecnetato de s?dio (Na99mTcO4) foi injetado via plexo orbital (IV). Decorridos trinta minutos da administra??o do radiof?rmaco, os animais foram sacrificados e submetidos a toracolaparotomia mediana para retirada do f?gado, ba?o, p?ncreas, est?mago, duodeno, intestino delgado, tire?ide, pulm?o, cora??o, rim, bexiga, m?sculo, f?mur e c?rebro. A detec??o da radioatividade foi feita com Contador Gama (Wizard, PerkinElmer USA), autom?tico. Calculou-se em seguida o percentual de atividade por grama de tecido (%ATI/g) do pertecnetato de s?dio (Na99m TcO4) em cada ?rg?o. Os valores da biodistribui??o do pertecnetato no ba?o, p?ncreas e m?sculo nos animais do grupo switch tiveram uma diferen?a significativamente maior do que os dos grupos C e S (p<0,05). Na tire?ide dos animais do grupo SD o pertecnetato teve menor capta??o em rela??o aos demais grupos, sendo estatisticamente significante quando comparada ao grupo S (p<0,05). A biodistribui??o pulmonar nos animais do grupo SD s? foi significativamente maior quando comparada a do grupo S (p<0,05). N?o houve diferen?a significante, para os demais ?rg?os. Em conclus?o, a t?cnica do desvio biliopancre?tico com switch duodenal alterou a biodistribui??o p?s-operat?ria do Na99mTcO4 em ?rg?os como tire?ide, pulm?o, ba?o, p?ncreas e m?sculo de ratos operados, devido a prov?veis altera??es metab?licas e estruturais causadas por t?cnica cir?rgica mutilante. O trabalho teve um car?ter multidisciplinar com a participa??o de pesquisadores de diferentes departamentos e laborat?rios, como N?cleo de Cirurgia Experimental, Departamento de Cirurgia, Laborat?rio de Radiobiologia e o Servi?o de Medicina Nuclear da Liga Norte-Riograndense contra o C?ncer, atestando o car?ter multidisciplinar da pesquisa
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Effects of Cannulation, BST Administration and Protein Degradability on Rumen and Duodenal Characteristics and Milk Production Response in Holstein Dairy CowsWinsryg, Margaret D. 01 May 1990 (has links)
Bovine somatotropin (bST) is a protein synthesized at the base of the brain and released by the pituitary gland into the circulatory system. BST is transported by the circulatory system and absorbed only by cells of target organs that possess cell surface receptors for the protein (11, 41). Its effect is initiated via a protein receptor initiation and cyclic AMP cascade . This effect on the cell continues well past the degradation of the bST molecule. BST is likely transported into the cell, where it is degraded . Its constituent blocks, amino acids, are used to synthesize new proteins or converted to other metabolites such as sugars (1).
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