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51.
Behavioral and neurochemical effects induced by subchronic combined exposure to toluene at 40 ppm and noise at 80 dB-A in rats 总被引:1,自引:0,他引:1
We investigated whether exposure to noise, in addition to its well-known potentiating effect on toluene-induced ototoxicity, may also exacerbate behavioral disturbances and brain neurochemical alterations produced by subchronic exposure to low toluene concentration. To test this hypothesis, we evaluated whether subchronic combined exposure (16 weeks, 104 h per week) to noise at 80 dB-A and toluene at 40 ppm potentiates the recently reported neurotoxic effects of subchronic exposure to 40 ppm toluene. Locomotor and rearing activities, sensitization to narcosis induced by acute toluene at high concentration, and tyrosine and tryptophan hydroxylase activities in the caudate-putamen and hippocampus were investigated in both male and female rats. Our results confirm that subchronic exposure to 40 ppm toluene significantly decreases rearing activity and leads to a sensitization to toluene-induced narcosis, as evaluated by loss of righting reflex, but fails to demonstrate any adverse effect of noise, alone or in combination with toluene. Given that toluene has addictive properties, the lack of potentiating behavioral and neurochemical effect of noise is discussed with regards to a recent study that has shown that methamphetamine neurotoxicity is potentiated by exposure to loud noise. 相似文献
52.
Amadou Kane Edmond Ekué Creppy Angelika Roth Robert Röschenthaler Guy Dirheimer 《Archives of toxicology》1986,58(4):219-224
The distribution of a single low dose of [3H]ochratoxin A (OTA) in different tissues of male Wistar rats, after administration by intubation, was investigated after 5 h, 24 h and 48 h. This dose corresponds to concentrations encountered in naturally contaminated feed (4 ppm). The distribution of [3H]-label varied with the time elapsed after administration; at 5 h the highest specific label was found in the stomach contents and in decreasing order in: intestinal contents, lung, liver, kidney, heart, fat, intestine, testes, and the lowest in muscles, spleen and brain. With exception of brain, fat, stomach and lung, all tissues showed maximum levels at 24 h, after which time the label decreased steadily, whereas in fat it increased.After a 12-week feeding experiment, with doses of 288.8 g/kg corresponding to an intake of 4 ppm in feed each 48 h, the DNA in liver and kidneys was investigated for damage. By the alkaline elution method combined with micro-spectrofluorimetric determinations of DNA, evidence for DNA single-strand breaks was obtained. These findings support reports on the carcinogenic action of OTA. 相似文献
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Isabel M. A. Brüggenwirth Maureen J. M. Werner René Adam Wojciech G. Polak Vincent Karam Michael A. Heneghan Arianeb Mehrabi Jürgen L. Klempnauer Andreas Paul Darius F. Mirza Johann Pratschke Mauro Salizzoni Daniel Cherqui Michael Allison Olivier Soubrane Steven J. Staffa David Zurakowski Robert J. Porte Vincent E. de Meijer all the other contributing centers the European Liver Intestine Transplant Association 《Transplant international》2021,34(10):1928-1937
High-risk combinations of recipient and graft characteristics are poorly defined for liver retransplantation (reLT) in the current era. We aimed to develop a risk model for survival after reLT using data from the European Liver Transplantation Registry, followed by internal and external validation. From 2006 to 2016, 85 067 liver transplants were recorded, including 5581 reLTs (6.6%). The final model included seven predictors of graft survival: recipient age, model for end-stage liver disease score, indication for reLT, recipient hospitalization, time between primary liver transplantation and reLT, donor age, and cold ischemia time. By assigning points to each variable in proportion to their hazard ratio, a simplified risk score was created ranging 0–10. Low-risk (0–3), medium-risk (4–5), and high-risk (6–10) groups were identified with significantly different 5-year survival rates ranging 56.9% (95% CI 52.8–60.7%), 46.3% (95% CI 41.1–51.4%), and 32.1% (95% CI 23.5–41.0%), respectively (P < 0.001). External validation showed that the expected survival rates were closely aligned with the observed mortality probabilities. The Retransplantation Risk Score identifies high-risk combinations of recipient- and graft-related factors prognostic for long-term graft survival after reLT. This tool may serve as a guidance for clinical decision-making on liver acceptance for reLT. 相似文献
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Insulin resistance is the rate-limiting step in the development of metabolic diseases, including type 2 diabetes. The gut microbiota has been implicated in host energy metabolism and metabolic diseases and is recognized as a quantitatively important organelle in host metabolism, as the human gut harbors 10 trillion bacterial cells. Gut microbiota break down various nutrients and produce metabolites that play fundamental roles in host metabolism and aid in the identification of possible therapeutic targets for metabolic diseases. Therefore, understanding the various effects of bacterial metabolites in the development of insulin resistance is critical. Here, we review the mechanisms linking gut microbial metabolites to insulin resistance in various insulin-responsive tissues. 相似文献
57.
Introduction1 Hepatic cavernous hemangioma (HCH) is a common benign lesion of the liver. The radiological features of HCH can resemble those of hepatic malignancies such as metastatic liver cancer, which make the preoperative definitive diagnosis difficult.Presentation of caseWe report the case of a 77-year-old woman who presented with a 2-month history of abdominal pain and per rectum fresh bleeding. The initial diagnosis at the referral hospital, based on computed tomography (CT) scan of the chest, abdomen, and pelvis, was sigmoid colon cancer with liver metastasis. Further evaluation at our hospital, the patient underwent colonoscopy and biopsy. Histopathological examination of the biopsy revealed an invasive moderately differentiated adenocarcinoma. The patient underwent laparoscopic sigmoidectomy and left hepatectomy. The histopathological examination of the sigmoid colon mass revealed an invasive moderately to poorly differentiated adenocarcinoma. One out of twenty lymph nodes is positive for metastatic carcinoma. The pathological stage is pT3, pN1a, pM0. The histopathological examination of the left hepatic lobe revealed two hyalinized cavernous hemangiomas with no malignancy is seen. The postoperative recovery was uneventful, and the patient was discharged home with regular follow-up in our outpatient clinic.DiscussionHCH is congenital vascular malformation and is the most common benign hepatic tumors. Fine-needle biopsy during diagnostic laparoscopy for undiagnosed multiple liver tumor can differentiate atypical HCH from colorectal metastasis but can potentially lead to rupture or seeding of cancer cells.ConclusionSurgical resection is necessary to determine if the mass is malignant in some atypical HCH mimicking liver metastasis to confirm the diagnosis with histopathologic examination. 相似文献
58.
Introduction and importanceThe incidence of patients with liver cirrhosis (LC) is increasing. Patients with LC are known to have a greater risk of postoperative morbidity and mortality than patients without LC. A treatment option such as pancreaticoduodenectomy (PD) has not been validated to be safe for these patients, especially those with pancytopenia due to portal hypertension (PH). Providing an effective treatment option for these patients is essential.Case presentationHerein, we describe a patient with pancreatic cancer with pancytopenia due to LC that was successfully treated with PD combined with splenectomy. The patient was a 70-year-old woman who was referred to our hospital for evaluation of a mass in the pancreatic head after she developed obstructive jaundice. She was diagnosed with T2N0M0, Stage IB pancreatic cancer and pancytopenia due to PH associated with LC. She received 2 cycles of adjuvant gemcitabine/S-1 chemotherapy and underwent radical subtotal stomach-preserving pancreaticoduodenectomy with splenectomy to improve her pancytopenia. Histopathological examination of the resected specimen revealed an R0 resection showing an Evans grade IIa histological response. Her pancytopenia improved rapidly after surgery.Clinical discussionStrict indications for PD, haemostatic control of intraoperative bleeding, and optimal perioperative management were important for preventing hepatic decompensation in this patient. Splenectomy is effective for thrombocytopenia due to LC; however, attention to postoperative complications such as overwhelming post-splenectomy infection and portal vein thrombosis is required.ConclusionFor patients with pancreatic cancer with pancytopenia due to LC, PD combined with splenectomy plus optimal perioperative management is effective. 相似文献
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60.
Attallah AM Tabll AA El-Sadany M Ibrahim TA El-Dosoky I 《Clinical and experimental medicine》2003,3(3):181-185
Immunological factors are important in the pathogenesis of a wide spectrum of hepatobiliary diseases. Using flow cytometry, we determined the changes in lymphocyte subsets and natural killer cells in 123 individuals (81 patients with liver disease and 42 healthy volunteers). The liver diseases included periportal fibrosis (PPF, 10 patients), liver cirrhosis (LC, 31 patients), and hepatocellular carcinoma (HCC, 40 patients). Schistosomiasis and viral hepatitis B and C were the putative etiological agents of liver diseases. Immunophenotyping by indirect immunofluorescence was conducted using monoclonal antibodies to CD3 (T-lymphocytes), CD4 (helper/inducer T-cells), CD8 (suppressor/cytotoxic T-cells), and CD57 (natural killer cells) cell surface markers. Immunophenotyping of PPF patients showed no significant changes in all markers compared with the healthy controls. However, there was a significant decrease ( P<0.01) in CD3 and CD4 T-cells, and a highly significant increase ( P<0.001) in CD57 T-cells in patients with LC or HCC. In addition, LC and HCC patients showed no significant change in CD8 T-cells compared with controls. In conclusion, the progression of liver diseases is associated with a dysregulation of cellular immune responses. T-lymphocytes and natural killer cells may play a role in the immunopathogenesis of liver cirrhosis and HCC. 相似文献