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101.
BackgroundNeurosteroids affect the balance between neuroexcitation and neuroinhibition but have been little studied in migraine. We compared the serum levels of pregnenolone sulfate, pregnanolone and estradiol in women with menstrually-related migraine and controls and analysed if a correlation existed between the levels of the three hormones and history of migraine and age.MethodsThirty women (mean age ± SD: 33.5 ± 7.1) with menstrually-related migraine (MM group) and 30 aged- matched controls (mean age ± SD: 30.9 ± 7.9) participated in the exploratory study. Pregnenolone sulfate and pregnanolone serum levels were analysed by liquid chromatography-tandem mass spectrometry, while estradiol levels by enzyme-linked immunosorbent assay.ResultsSerum levels of pregnenolone sulfate and pregnanolone were significantly lower in the MM group than in controls (pregnenolone sulfate: P = 0.0328; pregnanolone: P = 0.0271, Student’s t-test), while estradiol levels were similar. In MM group, pregnenolone sulfate serum levels were negatively correlated with history of migraine (R2 = 0.1369; P = 0.0482) and age (R2 = 0.2826, P = 0.0025) while pregnenolone sulfate levels were not age-related in the control group (R2 = 0.04436, P = 0.4337, linear regression analysis).ConclusionLow levels of both pregnanolone, a positive allosteric modulator of the GABAA receptor, and pregnenolone sulfate, a positive allosteric modulator of the NMDA receptor, involved in memory and learning, could contribute either to headache pain or the cognitive dysfunctions reported in migraine patients. Overall, our results agree with the hypothesis that migraine is a disorder associated with a loss of neurohormonal integrity, thus supporting the therapeutic potential of restoring low neurosteroid levels in migraine treatment.Supplementary InformationThe online version contains supplementary material available at 10.1186/s10194-021-01231-9.  相似文献   
102.
BACKGROUND: The determinants of a worse outcome in diabetic patients after an acute myocardial infarction (AMI) are controversial. They include delayed hospital admission, worse clinical presentation and lesser efficacy of accepted therapeutic interventions. Therefore, to improve our knowledge, we aimed to describe the clinical characteristics, treatment options and short-term outcomes of diabetic patients in a survey of consecutive AMI subjects admitted to the Italian coronary care unit (CCU) network in the current era of reperfusion. METHODS: The BLITZ study prospectively enrolled patients with AMI, within 48 hours of symptom onset, admitted to 296 out of the 341 existing Italian CCUs from October 15 to 29, 2001. Diabetic status was recorded by collecting clinical history. In-hospital and post-discharge management and outcomes were collected up to 30 days from admission. RESULTS: Overall, 434 of 1959 enrolled patients (22%) had a clinical diagnosis of diabetes. Diabetic patients were older, more frequently women, had a worse coronary risk profile, and an unfavorable clinical presentation compared to non-diabetics. Among 1275 patients with ST-elevation AMI, diabetics (20%) received a similar proportion of any reperfusion therapy (61 vs 66%, p = 0.10), but significantly less primary percutaneous coronary angioplasty (9 vs 16%, p = 0.003). Diabetic patients were treated less often with oral beta-blockers than non-diabetics both during hospitalization (56 vs 64%, p = 0.003) and at discharge (54 vs 61%, p = 0.01). In contrast, in-hospital use of angiotensin-converting enzyme inhibitors (76 vs 67%, p = 0.0003), digitalis (10 vs 5%, p = 0.0005), and diuretics (54 vs 36%, p < 0.0001) was more frequent among diabetics. During their index admission, subjects with diabetes had higher in-hospital mortality (11 vs 6%, p = 0.0004), as well as higher rates of reinfarction (6 vs 2%, p = 0.0003), new congestive heart failure (28 vs 14%, p < 0.0001), cardiogenic shock (10 vs 5%, p = 0.0005) or recurrent angina (22 vs 16%, p = 0.0034). A similar pattern was observed at 30-day follow-up. At multivariate analysis, diabetic status was not confirmed to be an independent predictor of 30-day mortality. CONCLUSIONS: Although diabetic patients with AMI admitted to the Italian CCU network have a higher in-hospital and 30-day morbidity and mortality rates compared to non-diabetics, a clinical diagnosis of diabetes has no independent predictive value on short-term outcome.  相似文献   
103.
Patients with cirrhosis are frequently submitted to radiological procedures that require the administration of contrast media. Contrast media is a well-known cause of renal failure, particularly in the presence of some predisposing conditions. However, it is not known whether cirrhosis constitutes a risk factor for contrast media-induced renal failure. The aim of this study was to assess the possible nephrotoxicity of contrast media in patients with cirrhosis. In a first protocol, renal function was evaluated with sensitive methods (glomerular filtration rate using iothalamate I 125 clearance and renal plasma flow using iodohippurate I 131 clearance) before and 48 hours after the administration of contrast media in 31 patients with cirrhosis (20 with ascites, 5 with renal failure). Solute-free water clearance, urine sodium, prostaglandins, and markers of tubular damage were also measured. The administration of contrast media was not associated with significant changes in renal function tests, neither in the whole group of patients nor in patients with ascites or renal failure. Urinary prostaglandin E2 and N-acetyl-beta-D-glucosaminidase increased significantly, but sodium and solute-free water excretion remained unchanged. In a second protocol, a different series of 60 patients with cirrhosis and renal failure were examined prospectively. No patient had renal failure due to contrast media. Only in 1 patient with septic shock was contrast media a possible contributing factor. In conclusion, the administration of contrast media is not associated with adverse effects on renal function in patients with cirrhosis. Cirrhosis does not appear to be a risk factor for the development of contrast media-induced nephrotoxicity.  相似文献   
104.
Aim: The Child Pugh and MELD are good methods for predicting mortality in patients with chronic liver disease. We investigated their performance as risk factors for failure to control bleeding, in-hospital overall mortality and death related to esophageal variceal bleeding episodes. Methods: From a previous collected database, 212 cirrhotic patients with variceal bleeding admitted to our hospital were studied. The predictive capability of Child Pugh and MELD scores were compared using c statistics. Results: The Child-Pugh and MELD scores showed marginal capability for predicting failure to control bleeding (the area under receiver operating characteristics curve (AUROC) values were < 0.70 for both). The AUROC values for predicting inhospital overall mortality of Child-Pugh and MELD score were similar: 0.809 (CI 95%, 0.710 - 0.907) and 0.88 (CI 95% 0.77-0.99,) respectively. There was no significant difference between them (p > 0.05). The AU-ROC value of MELD for predicting mortality related to variceal bleeding was higher than the Child-Pugh score: 0.905 (CI 95% 0.801-1.00) vs 0.794 (CI 95% 0.676 - 0.913) respectively (p < 0.05). Conclusions: MELD and Child-Pugh were not efficacious scores for predicting failure to control bleeding. The Child-Pugh and MELD scores had similar capability for predicting in-hospital overall mortality. Nevertheless, MELD was significantly better than Child-Pugh score for predicting in-hospital mortality related to variceal bleeding.  相似文献   
105.
Estradiol-17beta-D-glucuronide (E(2)17G), an endogenous metabolite of estradiol, induces a potent dose-dependent and reversible inhibition of bile flow in the rat. We analyzed the effect of a single dose of E(2)17G (15 micromol/kg, intravenously) to female rats on bile flow and the endocytic retrieval and function of the canalicular multidrug resistance-associated protein 2 (Mrp2) and the effect of pretreatment with dibutyryl-cyclic AMP (DBcAMP; 20 micromol/kg) on these measures. Bile flow was maximally inhibited by 85% within 10 minutes of E(2)17G and returned to 50% and 100% of control levels within 75 and 120 minutes, respectively. Western analysis of total homogenates and mixed plasma and intracellular membranes suggested partial internalization of Mrp2 during the acute phase of cholestasis at 20 minutes and during the period of recovery from cholestasis at 75 minutes, which returned to control levels by 180 minutes after E(2)17G. Confocal analysis confirmed Western studies and demonstrated endocytic retrieval of Mrp2 from the canalicular membrane into pericanalicular and intracellular domains. The biliary concentration and excretion of the model Mrp2 substrate, dinitrophenyl-S-glutathione (DNP-SG), was impaired in parallel with the extent of Mrp2 retrieval. Pretreatment with DBcAMP partially protected against maximal E(2)17G cholestasis and the endocytic retrieval and decreased function of Mrp2 at 20 minutes and significantly accelerated the exocytic insertion of Mrp2 into the canalicular membrane and the recovery of bile flow and biliary excretion of DNP-SG. In conclusion, these data indicate that E(2)17G induces endocytic internalization of Mrp2, which occurs in parallel with decreased bile flow and Mrp2 transport activity.  相似文献   
106.

Purpose of Review

The purpose of this review is to discuss the current evidence regarding the impact of sarcopenia on patients with cirrhosis awaiting liver transplantation and to determine if its presence should be considered a criterion for expedited transplantation or a contraindication for transplantation.

Recent Findings

Sarcopenia is a negative predictor of survival in patients on a waiting list and after liver transplant. The gut-liver axis and the liver-muscle axis have been explored to understand the complex pathophysiology of sarcopenia.

Summary

Sarcopenia is a frequent finding in patients with cirrhosis. The diagnosis is ideally based on cross-sectional image analysis (CT or MRI) and treatment consists of optimization of caloric and protein intake. To date, prioritizing tools for liver transplantation have not included nutrition or sarcopenia parameters. Patients with a low Model for End-Stage Liver Disease (MELD) or MELD-Na score and sarcopenia would benefit from prioritization for transplant in order to reduce time on waiting list and therefore mortality.
  相似文献   
107.

Purpose

Endotoxin is a component of the outer membrane of gram-negative bacteria that live in the intestine. Endotoxinemia is reported in non-alcoholic fatty liver disease and in cirrhotic patients, causing various biological and clinical effects in the host. It is not known whether endotoxinemia occurs in chronic hepatitis C patients (CHC), therefore we evaluated the occurrence of endotoxinemia and its effect on inflammation, liver damage, insulin resistance (IR) and atherosclerosis.

Methods

Consecutive CHC patients assessed by liver biopsy were enrolled. Endotoxinemia was evaluated by LAL test. IR was estimated by HOMA-IR. Serum TNF-α, IL-8, adiponectin and MCP-1 were measured with ELISA tests. Oxidative stress was estimated by circulating IgG against malondialdehyde adducts with human serum albumin (MDA-HAS). Carotid atherosclerosis was assessed by ultrasonography.

Results

Endotoxinemia was found in 60% of the 126 patients enrolled. A serum level-dependent association between endotoxinemia, steatosis (p?<?0.001) and HOMA-IR (p?<?0.006) was observed. Patients with endotoxinemia showed significant increase in TNF-α and IL8 levels. TNF-α correlated with steatosis (p < ?0.001) and HOMA-IR (p?<?0.03), whereas IL8 correlated with steatosis (p?= ?<0.001), TNF-α (p?<?0.04) and atherosclerosis (p?<?0.01). The highest levels of endotoxinemia were associated with oxidative stress and a higher prevalence of carotid atherosclerosis. Multivariate logistic regression analysis showed that the independent factors associated with endotoxinemia were hepatic steatosis, HOMA-IR, IL8 and MDA-HAS.

Conclusions

Endotoxinemia occurs with high frequency in CHC patients and contributes to the development of hepatic steatosis, IR and atherosclerosis through increased pro-inflammatory cytokines and oxidative stress. Anti-endotoxin treatment could be of clinical relevance.
  相似文献   
108.
The success of scaffold‐based bone regeneration approaches strongly depends on the performance of the biomaterial utilized. Within the efforts of regenerative medicine towards a restitutio ad integrum (i.e. complete reconstruction of a diseased tissue), scaffolds should be completely degraded within an adequate period of time. The degradation of synthetic bone substitute materials involves both chemical dissolution (physicochemical degradation) and resorption (cellular degradation by osteoclasts). Responsible for bone resorption are osteoclasts, cells of haematopoietic origin. Osteoclasts play also a crucial role in bone remodelling, which is essential for the regeneration of bone defects. There is, however, surprisingly limited knowledge about the detailed effects of osteoclasts on biomaterials degradation behaviour. This review covers the relevant fundamental knowledge and progress made in the field of osteoclast activity related to biomaterials used for bone regeneration. In vitro studies with osteoclastic precursor cells on synthetic bone substitute materials show that there are specific parameters that inhibit or enhance resorption. Moreover, analyses of the bone–material interface reveal that biomaterials composition has a significant influence on their degradation in contact with osteoclasts. Crystallinity, grain size, surface bioactivity and density of the surface seem to have a less significant effect on osteoclastic activity. In addition, the topography of the scaffold surface can be tailored to affect the development and spreading of osteoclast cells. The present review also highlights possible areas on which future research is needed and which are relevant to enhance our understanding of the complex role of osteoclasts in bone tissue engineering. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
109.
110.
Papillary thyroid microcarcinoma (mPTC), is a very frequent incidental finding with a frequency varying from a few percent to 35% at postmortem histopathologic examinations. However, the presence of mPTC in patients undergoing thyroidectomy for multinodular goiter (MNG) and for Graves' disease (GD) has been found to be lower. Patients with medullary thyroid carcinoma (MTC) and papillary thyroid carcinoma (PTC) association have been published as anecdotal case reports, as well as kindred with familial MTC or multiple endocrine neoplasia (MEN) 2A with some members simultaneously affected by MTC and PTC. We studied the prevalence and the biological behavior of MTC associated with PTC, with particular attention to those cases in which a mPTC was incidentally found. Twenty-seven of 196 (13.8%) MTC cases showed an association with PTC and in particular 21 of 190 (11.05%) with an incidental mPTC. This percentage is higher than that reported in the literature on the association of mPTC with GD (2.8%-4.5%) and MNG (3%). Also the percentage of the more general association of MTC/PTC, not restricted to mPTC, found in our series (13.8%) is higher than that reported in studies that analyzed the prevalence of PTC (any size) in patients treated for MNG (7.5%). A similarly high percentage of MTC/PTC had not been reported before and in particular there are no reports on large series of MTC/PTC. We also analyzed the epidemiologic, clinical, and pathologic features of MTC associated and not associated with PTC without finding any difference. In particular the outcome of the MTC did not appear to be influenced by the presence of the PTC and the specific radioiodine treatments. Moreover, although we cannot completely exclude a shared pathogenic event as the cause of both MTC and PTC, the molecular analysis of RET gene alterations did not show any common mutation.  相似文献   
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