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1.
Sci Total Environ ; 926: 172017, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38552976

RESUMO

As global warming intensifies, extreme heat is becoming increasingly frequent. These extreme heatwaves have decreased the milk production of dairy animals such as cows and goats and have caused significant damage to the entire dairy industry. It is known that heat stress (HS) can induce the apoptosis and autophagy of mammary epithelial cells (MECs), leading to a decrease in lactating MECs. L-arginine can effectively attenuate HS-induced decreases in milk yield, but the exact mechanisms are not fully understood. In this study, we found that HS upregulated the arginine sensor CASTOR1 in mouse MECs. Arginine activated mTORC1 activity through CASTOR1 and promoted mitochondrial biogenesis through the mTORC1/PGC-1α/NRF1 pathway. Moreover, arginine inhibited mitophagy through the CASTOR1/PINK1/Parkin pathway. Mitochondrial homeostasis ensures ATP synthesis and a stable cellular redox state for MECs under HS, further alleviating HS-induced damage and improving the lactation performance of MECs. In conclusion, these findings reveal the molecular mechanisms by which L-arginine relieves HS-induced mammary gland injury, and suggest that the intake of arginine-based feeds or feed additives is a promising method to increase the milk yield of dairy animals in extreme heat conditions.


Assuntos
Transtornos de Estresse por Calor , Lactação , Feminino , Animais , Bovinos , Camundongos , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Leite/metabolismo , Resposta ao Choque Térmico , Homeostase , Arginina/metabolismo
2.
Materials (Basel) ; 17(2)2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38276415

RESUMO

In the realm of engineering rotary excavation, the rigid and brittle nature of the Polycrystal Diamond Compact (PDC) layer poses challenges to the impact resistance of conical teeth. This hinders their widespread adoption and utilization. In this paper, the Abaqus simulation is used. By optimizing the parameters of the radius of the cone top arc, we analyzed the changing law of the parameters of large-diameter D30 series conical PDC teeth, such as the equivalent force, impact force, and energy absorption of the conical teeth during the impact process, and optimized the best structure of the conical PDC teeth. After being subjected to a high temperature and high pressure, we synthesized the specimen for impact testing and analyzed the PDC layer crack extension and fracture failure. The findings reveal the emergence of a stress ring below the compacted area of the conical tooth. As the radius of the cone top arc increases, so does the area of the stress ring. When R ≥ 10 mm, the maximum stress change is minimal, and at R = 10 mm, the stress change in its top unit is relatively smooth. Optimal impact resistance is achieved, withstanding a total impact work value of 7500 J. Extrusion cracks appear in the combined layer part of PDC layers I and II, but the crack source is easy to produce in the combined layer of PDC layer II and the alloy matrix and extends to both sides, and the right side extends to the surface of the conical tooth in a "dragon-claw". The failure morphology of the conical teeth includes ring shedding at the top of the PDC layer, the lateral spalling of the PDC layer, and the overall cracking of the conical teeth. Through this study, we aim to promote the popularization and application of large-diameter conical PDC teeth in the field of engineering rotary excavation.

3.
J Oncol ; 2023: 2733232, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36968641

RESUMO

Colorectal cancer (CRC) is a common and highly lethal gastrointestinal malignancy. Immunotherapy has shown positive efficacy in the treatment of CRC; however, only a minority of patients benefit from immunotherapy. The aim of this study is to construct a cuproptosis-related lncRNA (CRLs) risk score model to predict the prognosis and immune infiltration of CRC patients. Firstly, we synthetically analyzed 19 cuproptosis-related genes (CRGs) from CRC samples derived from the TCGA and obtained 33 CRLs that were significantly associated with prognosis. Next, we defined three cuproptosis modification patterns via consensus clustering analysis (C1, C2, and C3). Further analysis showed that there were significant differences in the abundance of B cells, NK cells, fibroblasts, monocytes, CD8+ cells, bone marrow dendritic cells, and cytotoxic lymphocytes in different clusters. In addition, the LASSO regression screened out 6 individual CRLs (AC009315.1, PLS3-AS1, ZEB1-AS1, AC007608.3, AC010789.2, and AC010207.1) closely related to the prognosis of CRC. We found that the low-risk group had better survival prognoses in patients. Furthermore, the high-risk group had lower immune scores and exhibited lower CD8+ T cell infiltration. Moreover, the low-risk group had lower immune exclusion, immune dysfunction and TIDE scores than the high-risk group. Interestingly, the lncRNAs in our risk model were positively associated with most immune checkpoints. CD274 (PD-L1), CTLA4, and HAVCR2 (TIM3) were positively correlated with risk scores. Moreover, MSI-H patients had lower risk scores than MSI-L patients, and IPS scores were significantly higher in the low CRLs score group. In conclusion, we constructed a novel risk score model with6 lncRNAs related to cuproptosis, which may be a potential biomarker for evaluating the prognosis and immune treatment for CRC.

4.
Int J Surg ; 109(4): 850-860, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36974733

RESUMO

BACKGROUND: The purpose of this research was to determine the index that contributes the most to assessing the effectiveness of weight loss 1 year following bariatric surgery and to implement it as the clinical outcome to develop and confirm a nomogram to predict whether bariatric surgery would be effective. METHODS: Patient information was extracted from the Chinese Obesity and Metabolic Surgery Database for this retrospective study. The most contributing weight loss effectiveness evaluation index was created using canonical correlation analysis (CCA), and the predictors were screened using logistic regression analysis. A nomogram for estimating the likelihood of effectiveness of weight loss was constructed, and its performance was further verified. RESULTS: Information was obtained for 540 patients, including 30 variables. According to the CCA, ≥25 percentage total weight loss was found to be the most correlated with patient information and contribute the most as a weight loss effectiveness evaluation index. Logistic regression analysis and nomogram scores identified age, surgical strategy, abdominal circumference, weight loss history, and hyperlipidemia as predictors of effectiveness in weight loss. The prediction model's discrimination, accuracy, and clinical benefit were demonstrated by the consistency index, calibration curve, and decision curve analysis. CONCLUSIONS: The authors determined a 25 percentage total weight loss as an index for weight loss effectiveness assessment by CCA and next established and validated a nomogram, which demonstrated promising performance in predicting the probability of effectiveness of weight loss in bariatric surgery. The nomogram might be a valuable tool in clinical practice.


Assuntos
Cirurgia Bariátrica , Nomogramas , Humanos , Estudos Retrospectivos , Obesidade , Probabilidade
5.
Obes Surg ; 32(5): 1631-1640, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35288862

RESUMO

BACKGROUND: Long-term weight loss effect of bariatric surgeries for patients with Prader-Willi Syndrome (PWS) remains controversial since factors like postoperative home care intensity may impact the outcome. The aim of this study was to evaluate the role of home care intensity on long-term weight loss effect of bariatric surgery in patients with PWS. METHODS: This was a prospective observational study on patients with PWS undergoing bariatric surgery and patients were enrolled from July 2015 to December 2016. Detailed information of patients' weight and behaviors was recorded by caregivers postoperatively. The intensities of home care applied to patients were classified into four categories (high, moderate, low, and very low) according to the records. RESULTS: Six cases (3 males, 3 females) were enrolled in this study with LSG (n = 2), RYGB (n = 3), and LSG-DJB (n = 1) as their primary operation. The mean BMI of these participants was 46.78 ± 11.63 kg/m2, and the mean age was 17.66 ± 6.59 years. All patients had at least 5 years of follow-ups, and the %EWL were 51.57 ± 23.36%, 64.54 ± 18.97%, 35.34 ± 36.53%, 19.45 ± 41.78%, and - 4.74 ± 71.50% in the half, first, second, third, and fifth year after surgery respectively. Two patients with high-intensity home care achieved a %EWL of 70.57 ± 8.86% in the fifth year after surgery. CONCLUSIONS: Overall long-term weight loss of bariatric surgery for patients with PWS was not found through the follow-ups. Two patients with high-intensity home care maintained weight loss at the fifth-year follow-up, suggesting a pivotal role of high-intensity home care in long-term outcomes of bariatric surgery in patients with PWS.


Assuntos
Cirurgia Bariátrica , Serviços de Assistência Domiciliar , Obesidade Mórbida , Síndrome de Prader-Willi , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Obesidade Mórbida/cirurgia , Síndrome de Prader-Willi/complicações , Síndrome de Prader-Willi/cirurgia , Redução de Peso , Adulto Jovem
6.
Obes Surg ; 32(3): 819-828, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35088249

RESUMO

BACKGROUND: Postoperative nausea and vomiting (PONV) is common side effect after gastrointestinal surgery. It causses discomfort, increase risk of incision disruption, bleeding and airway blockage. This study aimed to investigate the incidence and severity of PONV and determine whether preoperative reflux or regurgitation symptoms influence PONV in patients undergoing bariatric surgery. METHODS: Patients with obesity underwent laparoscopic sleeve gastrectomy (LSG) and laparoscopic Roux-en-Y gastric bypass (LRYGB) in our center between January 2016 and December 2018 were divided into PONV and NoPONV group and analyzed retrospectively. PONV and postoperative pain visual analogue scale (VAS) were analyzed after surgery. A 1:1 propensity score matching (PSM) method was performed, and multivariable logistic regression analyses were used to identify predictors for PONV. RESULTS: There were 483 patients enrolled, with a mean age of 30.19 ± 9.96 years, and 134 pairs of matched patients were selected from PONV group and NoPONV group after PSM. PONV occurred in 288 (59.6%) patients after bariatric surgery (77.4% after LSG vs 21.5% after LRYGB, p < 0.001). In PONV group, 210 (72.9%) were female, preoperative reflux or regurgitation symptoms were 128 (33.6%). Multivariable analysis found that preoperative reflux or regurgitation symptoms were independent risk factors for PONV after LSG, with an OR of 2.78 (95% CI: 1.12-6.93, p = 0.028). CONCLUSIONS: Incidence of PONV after bariatric surgery is high. For the first time, this study valued preoperative reflux or regurgitation symptoms as risk factors that may promote PONV after bariatric surgery. Patients with preoperative symptoms undergoing LSG have a higher risk of PONV, so these patients should be carefully evaluated for the feasibility of LSG before surgery.


Assuntos
Cirurgia Bariátrica , Derivação Gástrica , Refluxo Gastroesofágico , Laparoscopia , Obesidade Mórbida , Adulto , Cirurgia Bariátrica/efeitos adversos , Feminino , Gastrectomia/efeitos adversos , Gastrectomia/métodos , Derivação Gástrica/métodos , Refluxo Gastroesofágico/epidemiologia , Humanos , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Masculino , Obesidade Mórbida/cirurgia , Complicações Pós-Operatórias/epidemiologia , Náusea e Vômito Pós-Operatórios/epidemiologia , Náusea e Vômito Pós-Operatórios/etiologia , Pontuação de Propensão , Estudos Retrospectivos , Adulto Jovem
8.
J Metab Bariatr Surg ; 9(1): 1-6, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36686896

RESUMO

Postprandial hyperinsulinemic hypoglycemia (PHH) is one of the serious complications after bariatric surgery, it can lead life-threatening neuroglycopenic symptoms, such as seizures, disorientation, impairment of version and loss of consciousness without any premonitory. The presentation, prevalence, diagnosis, pathology and treatment are reviewed in this summary.

9.
Obes Surg ; 30(2): 618-629, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31758470

RESUMO

BACKGROUND: Obesity has become a global epidemic. Surgical treatment of obesity and metabolic disorders in China is increasing rapidly, but it is still a new discipline even to health professionals. As an important member of the multidisciplinary team, the knowledge and attitudes of nurses provide crucial health care to the patients and support to surgeons. OBJECTIVES: To study the Chinese nurses' knowledge of obesity and metabolic disorders, and attitudes towards bariatric surgery and to improve their capability of work in this new discipline. METHODS: This is a multicenter study, with the questionnaire distributed to cooperative hospitals in the form of an electronic questionnaire by the First Affiliated Hospital of Jinan University in April 2018. A questionnaire was designed to investigate nurses' demographic, knowledge, and attitude towards obesity, weight loss, and bariatric surgery. RESULTS: A total of 5311 questionnaires were received, with an effective rate of 91.8% (4878 questionnaires); 65.2% of nurses had a normal BMI. Nurses generally had a high knowledge of obesity and related cardiovascular diseases (98.6%) and type 2 diabetes mellitus (90.2%). However, there was a lack of knowledge in other related aspects, for example its relations to carcinoma (49.5%), gastroesophageal reflux disease (40.1%), and psychological disorders (49.1%), which are controversial issues in bariatric surgery. It was found that education (p < 0.05) had an important influence to nurses' knowledge about the comorbidities of obesity. Female nurses had a higher tendency to choose weight loss than males, but male nurses did physical exercise more frequently than females (p < 0.05). Their acceptance of safety (25.1%) and efficacy (22.9%) of bariatric surgery is low, with concerns predominantly about postoperative complications and adverse effects. Surgical nurses had a more optimistic attitude towards surgery (p < 0.05). CONCLUSIONS: Chinese nurses have poor knowledge of obesity-related metabolic disorders and also have poor acceptance of surgical treatment modalities. Our findings suggest that it is crucial to enhance the continuing education of Chinese nurses for obesity, metabolic disorders, and bariatric surgery.


Assuntos
Atitude do Pessoal de Saúde , Cirurgia Bariátrica , Conhecimentos, Atitudes e Prática em Saúde , Enfermeiras e Enfermeiros , Obesidade/cirurgia , Adolescente , Adulto , Cirurgia Bariátrica/enfermagem , Cirurgia Bariátrica/psicologia , China/epidemiologia , Comorbidade , Escolaridade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Enfermeiras e Enfermeiros/psicologia , Enfermeiras e Enfermeiros/estatística & dados numéricos , Obesidade/enfermagem , Obesidade/psicologia , Obesidade Mórbida/enfermagem , Obesidade Mórbida/psicologia , Obesidade Mórbida/cirurgia , Inquéritos e Questionários , Redução de Peso , Adulto Jovem
10.
Entropy (Basel) ; 21(2)2019 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33266880

RESUMO

In this study, an effective way of applying Ti/Ni deposited coating to the surface of diamond single crystal particles by magnetron sputtering was proposed and novel high-entropy alloy (HEA)/diamond composites were prepared by spark plasma sintering (SPS). The results show that the interfacial bonding state of the coated diamond composite is obviously better than that of the uncoated diamond composite. Corresponding mechanical properties such as hardness, density, transverse fracture strength and friction properties of the coated diamond composite were also found to be better than those of the uncoated diamond composite. The effects of interface structure and defects on the mechanical properties of HEA/diamond composites were investigated. The research directions for further improving the structure and properties of high-entropy alloy/diamond composites were proposed.

11.
Entropy (Basel) ; 20(12)2018 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-33266648

RESUMO

This study reports the results of the addition of diamonds in the sintering process of a FCC-structured CoCrFeNiMo high-entropy alloy. The effect of raw powder states such as elemental mixed (EM) powder, gas atomization (GA) powder and mechanical alloying (MA) powder on the uniformity of constituent phase was also investigated. Examination of microstructure and evaluation of mechanical properties of the composites depending on the mixing processes were performed. As a result, GA+MA powder composite showed the highest mechanical properties. The experimental results indicated that the powder manufacturing method was an essential parameter to determine the quality of HEA/diamond composites such as the uniformity of phase and binding behavior.

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