160 resultados para Meibomian gland dysfunction


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The acute renal effects of hypoxemia and the ability of the co-administration of an angiotensin converting enzyme inhibitor (perindoprilat) and an adenosine receptor antagonist (theophylline) to prevent these effects were assessed in anesthetized and mechanically-ventilated rabbits. Renal blood flow (RBF) and glomerular filtration rate (GFR) were determined by the clearances of para-aminohippuric acid and inulin, respectively. Each animal acted as its own control. In 8 untreated rabbits, hypoxemia induced a significant drop in mean blood pressure (-12 +/- 2%), GFR (-16 +/- 3%) and RBF (-12 +/- 3%) with a concomitant increase in renal vascular resistance (RVR) (+ 18 +/- 5%), without changes in filtration fraction (FF) (-4 +/- 2%). These results suggest the occurrence of both pre- and postglomerular vasoconstriction during the hypoxemic stress. In 7 rabbits pretreated with intravenous perindoprilat (20 microg/kg), the hypoxemia-induced changes in RBF and RVR were prevented. FF decreased significantly (-18 +/- 2%), while the drop in GFR was partially blunted. These results could be explained by the inhibition of the angiotensin-mediated efferent vasoconstriction by perindoprilat. In 7 additional rabbits, co-administration of perindoprilat and theophylline (1 mg/kg) completely prevented the hypoxemia-induced changes in RBF (+ 11 +/- 3%) and GFR (+ 2 +/- 3%), while RVR decreased significantly (-14 +/- 3%). Since adenosine and angiotensin II were both shown to participate, at least in part, in the renal changes induced by hypoxemia, the beneficial effects of perindoprilat and theophylline in this model could be mediated by complementary actions of angiotensin II and adenosine on the renal vasculature.

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SUMMARY Radiotherapy is commonly and efficiently used to treat solid cancer in the clinic. Experimental evidence however suggests that radiation can promote tumor progression by inducing chronic modifications of the tumor microenvironment. Clinically, these observations are highly relevant to aggressive tumoral lesions relapsing after radiation therapy, a leading cause of patients' death. The investigation and understanding of the biological mechanisms implicated in the malignant progression of post-radiation relapses are therefore of major importance. Here we used a syngeneic (immunocompetent) breast cancer orthotopic xenograft model, to show that local irradiation of the mammary gland promotes the appearance of an invasive and metastatic tumor phenotype. Previous studies in our laboratory revealed that inhibition of tumor-induced angiogenesis and consequent increase in tumor hypoxia promotes metastasis formation through the activation of pro-invasive programs in the tumor cells. Our results extend these observations suggesting that mammary gland irradiation induces the recruitment of CD11b+ cells to both the primary tumor and the lungs at pre-metastatic stages through the hypoxia-dependent induction of Kit-ligand (KITL) expression in primary tumors. Abrogation of KITL expression in tumor cells prevented CD11 b+ cells accumulation in both the primary tumor and lungs and significantly reduced metastases of tumors growing in irradiated mammary gland. Importantly, irradiated mammary gland enhanced tumor-induced mobilization of circulating CD11b+cKit+ myelomonocytic cells through a HIF1- and KITL-dependent process. By cell transfer experiments, mobilized circulating CD11b+cKit+ cells were shown to supply both tumor- and lungs infiltrating CD11b+ cells. Using a blocking antibody against cKit (the KITL receptor), the mobilization of CD11b+cKit+ ceils was prevented as well as lung metastases derived from tumors growing in irradiated mammary gland. Taken together, these results indicate that tumors growing in a pre-irradiated mammary gland partially promote their malignant progression through the distant mobilization of circulating myelomonocytic precursor cells. They identify KITL inhibition and/or cKit receptor neutralization as potentially promising therapeutic approaches for post-radiation relapses. RESUME La radiothérapie est largement utilisée comme traitement de choix de nombreux types de cancers. L'agressivité des récidives tumorales observée en clinique après radiothérapie suggère cependant que le recours à l'irradiation pourrait dans certains cas accélérer la progression tumorale. De récents travaux expérimentaux ont en effet permis d'appuyer cette hypothèse, en montrant notamment l'effet néfaste des modifications chroniques de l'environnement induites par l'irradiation sur la progression tumorale. A l'aide d'un modèle murin syngénique orthotopique de cancer de sein, nous avons pu montrer que l'irradiation locale de la glande mammaire facilite l'invasion et la dissémination métastatique des cellules tumorales en favorisant le recrutement de cellules myéloïdes CD11 b+ vers la tumeur primaire et les poumons à un stade pré-métastatique. Comme mécanisme impliqué dans le recrutement des cellules CD11b+, nous avons pu observer après irradiation locale de la glande mammaire une expression augmentée de Kit-ligand (KITL) dans la tumeur (induite par l'hypoxie) ainsi que la mobilisation de cellules myéloïdes circulantes exprimant le récepteur cKit et précurseurs des cellules CD11b+ infiltrant la tumeur et les poumons. En empêchant la mobilisation par la tumeur de cellules circulantes cKit+ par des approches à la fois génétique et pharmacologique nous avons pu prévenir l'accumulation de cellules myéloïdes CD11 b+ dans la tumeur primaire et les poumons ainsi que la dissémination métastatique induites par' l'irradiation de la glande mammaire. De façon générale, ces résultats montrent que la progression agressive des tumeurs qui se développent dans un environnement irradié repose à la fois sur l'expression tumorale de KITL et la mobilisation de cellules myéloïdes précurseurs cKit*. Ils auront permis d'identifier KITL et/ou cKit comme des cibles thérapeutiques potentielles intéressantes pour le traitement des récidives tumorales après radiothérapie.

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OBJECTIVES: To evaluate the combination of ultrasound (US) + fine-needle aspiration (FNA) in the assessment of salivary gland tumours in the hands of the otolaryngologist. DESIGN: A retrospective review of case notes was performed. SETTING: Two university teaching hospitals in Switzerland. PARTICIPANTS: One hundred and three patients with a total of 106 focal masses of the salivary glands were included. Clinician-operated US + FNA were the first line of investigation for these lesions. All patients underwent surgical excision of the lesion, which allowed for confirmation of diagnosis by histopathology in 104 lesions and by laboratory testing in two lesions. MAIN OUTCOME MEASURES: Primary--diagnostic accuracy in identifying true salivary gland neoplasms and detecting malignancy. Secondary--predicting an approximate and specific diagnosis in these tumours. RESULTS: The combination of US + FNA achieved a diagnostic accuracy of 99% in identifying and differentiating true salivary gland neoplasms from tumour-like lesions. In detecting malignancy, this combination permitted an accuracy of 98%. An approximate diagnosis was possible in 89%, and a specific diagnosis in 69% of our patients. CONCLUSIONS: Due to economic factors and a high diagnostic accuracy, the combination of US + FNA represents the investigation method of choice for most salivary gland tumours. We suggest that the otolaryngologist be employed in carrying out these procedures, as is already the rule in other medical specialties, while computed tomography and magnetic resonance imaging should be reserved to those few lesions, which cannot be delineated completely by sonography.

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PURPOSE: To report a patient with an adenocarcinoma in a pleomorphic adenoma of the lacrimal gland. Adenocarcinoma constitutes a distinct group of epithelial malignancies of the lacrimal gland. METHODS: The clinical presentation, workup, surgical approach, and pathological findings were reviewed. RESULTS: A 56-year-old man presented with a 3-month history of a lacrimal fossa mass. This patient presented a painless mass in the upper outer eyelid with significant displacement of the globe. The tumor was localized to the lacrimal gland. Radiological investigations showed a round, well-defined lesion in the fossa of the lacrimal gland. We performed a lateral orbitotomy; en bloc resection was accomplished. The final specimen showed an adenocarcinoma in a pleomorphic adenoma. No recurrences were detected during follow-up. CONCLUSION: Although adenocarcinoma has rarely been reported in association with a pleomorphic adenoma of the lacrimal gland, this combination can exist. If the malignant tumor is limited in the pleomorphic adenoma, the prognosis appears to be better than in cases of local extension. Adjuvant therapy, radiation or others, are not useful.

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BACKGROUND: In heart transplantation, antibody-mediated rejection (AMR) is diagnosed and graded on the basis of immunopathologic (C4d-CD68) and histopathologic criteria found on endomyocardial biopsies (EMB). Because some pathologic AMR (pAMR) grades may be associated with clinical AMR, and because humoral responses may be affected by the intensity of immunosuppression during the first posttransplantation year, we investigated the incidence and positive predictive values (PPV) of C4d-CD68 and pAMR grades for clinical AMR as a function of time. METHODS: All 564 EMB from 40 adult heart recipients were graded for pAMR during the first posttransplantation year. Clinical AMR was diagnosed by simultaneous occurrence of pAMR on EMB, donor specific antibodies and allograft dysfunction. RESULTS: One patient demonstrated clinical AMR at postoperative day 7 and one at 6 months (1-year incidence 5%). C4d-CD68 was found on 4,7% EMB with a "decrescendo" pattern over time (7% during the first 4 months vs. 1.2% during the last 8 months; P < 0.05). Histopathologic criteria of AMR occurred on 10.3% EMB with no particular time pattern. Only the infrequent (1.4%) pAMR2 grade (simultaneous histopathologic and immunopathologic markers) was predictive for clinical AMR, particularly after the initial postoperative period (first 4 months and last 8 months PPV = 33%-100%; P < 0.05). CONCLUSION: In the first posttransplantation year, AMR immunopathologic and histopathologic markers were relatively frequent, but only their simultaneous occurrence (pAMR2) was predictive of clinical AMR. Furthermore, posttransplantation time may modulate the occurrence of C4d-CD68 on EMB and thus the incidence of pAMR2 and its relevance to the diagnosis of clinical AMR.

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Endocannabinoids and cannabinoid 1 (CB(1)) receptors have been implicated in cardiac dysfunction, inflammation, and cell death associated with various forms of shock, heart failure, and atherosclerosis, in addition to their recognized role in the development of various cardiovascular risk factors in obesity/metabolic syndrome and diabetes. In this study, we explored the role of CB(1) receptors in myocardial dysfunction, inflammation, oxidative/nitrative stress, cell death, and interrelated signaling pathways, using a mouse model of type 1 diabetic cardiomyopathy. Diabetic cardiomyopathy was characterized by increased myocardial endocannabinoid anandamide levels, oxidative/nitrative stress, activation of p38/Jun NH(2)-terminal kinase (JNK) mitogen-activated protein kinases (MAPKs), enhanced inflammation (tumor necrosis factor-α, interleukin-1β, cyclooxygenase 2, intracellular adhesion molecule 1, and vascular cell adhesion molecule 1), increased expression of CB(1), advanced glycation end product (AGE) and angiotensin II type 1 receptors (receptor for advanced glycation end product [RAGE], angiotensin II receptor type 1 [AT(1)R]), p47(phox) NADPH oxidase subunit, β-myosin heavy chain isozyme switch, accumulation of AGE, fibrosis, and decreased expression of sarcoplasmic/endoplasmic reticulum Ca(2+)-ATPase (SERCA2a). Pharmacological inhibition or genetic deletion of CB(1) receptors attenuated the diabetes-induced cardiac dysfunction and the above-mentioned pathological alterations. Activation of CB(1) receptors by endocannabinoids may play an important role in the pathogenesis of diabetic cardiomyopathy by facilitating MAPK activation, AT(1)R expression/signaling, AGE accumulation, oxidative/nitrative stress, inflammation, and fibrosis. Conversely, CB(1) receptor inhibition may be beneficial in the treatment of diabetic cardiovascular complications.

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Context: Subclinical thyroid dysfunction is common in older people. However, its clinical importance is uncertain. Objective: Our objective was to determine the extent to which subclinical hyperthyroidism and hypothyroidism influence the risk of heart failure and cardiovascular diseases in older people. Setting and Design: The Prospective Study of Pravastatin in the Elderly at Risk (PROSPER) is an prospective cohort study. Patients: Patients included men and women aged 70-82 yr (n = 5316) with known cardiovascular risk factors or previous cardiovascular disease. Main Outcome Measures: Incidence rate of heart failure hospitalization, atrial fibrillation, and cardiovascular events and mortality according to baseline thyroid status were evaluated. Euthyroid participants (TSH =0.45-4.5 mIU/liter) were compared with those with subclinical hyperthyroidism (TSH <0.45 mIU/liter) and those with subclinical hypothyroidism (TSH ≥4.5 mIU/liter, both with normal free T(4)). Results: Subclinical hyperthyroidism was present in 71 participants and subclinical hypothyroidism in 199 participants. Over 3.2 yr follow-up, the rate of heart failure was higher for subclinical hyperthyroidism compared with euthyroidism [age- and sex-adjusted hazard ratio (HR) = 2.93, 95% confidence interval (CI) = 1.37-6.24, P = 0.005; multivariate-adjusted HR = 3.27, 95% CI = 1.52-7.02, P = 0.002). Subclinical hypothyroidism (only at threshold >10 mIU/liter) was associated with heart failure (age- and sex-adjusted HR = 3.01, 95% CI = 1.12-8.11, P = 0.029; multivariate HR = 2.28, 95% CI = 0.84-6.23). There were no strong evidence of an association between subclinical thyroid dysfunction and cardiovascular events or mortality, except in those with TSH below 0.1 or over 10 mIU/liter and not taking pravastatin. Conclusion: Older people at high cardiovascular risk with low or very high TSH along with normal free T(4) appear at increased risk of incident heart failure.

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Background: Postoperative cognitive dysfunction (POCD) occurs frequently after cardiac surgery. Some data suggest that inflammation plays a key role in the development of POCD. N-3 fatty acids have been shown to have a beneficial effect on inflammation. We hypothesised that perioperative n-3 enriched nutrition therapy would reduce the incidence of POCD in this group of patients. Methods: Randomized, double blind placebo controlled trial in patients aged 65 or older undergoing elective cardiac surgery with cardiopulmonary bypass. 2x 250 mL placebo (Ensure Plus™, Abbott Nutrition) or n-3 enriched nutrition therapy (ProSure™ Abbott Nutrition) were administered for ten days starting 5 days prior to surgery. Cognition was assessed preoperatively and 7 days after surgery with the Consortium to Establish a Registry for Alzheimer's Disease - Neuropsychological Assessment Battery (CERAD-NAB) [1]. Results: 16 patients were included. Mean age was 72 } 5.3 for placebo and 75 } 4.8 for ProSure™ respectively. CRP and IL-6 did not differ significantly between groups preoperatively and on postoperative days 1, 3, and 7. Preoperative CERAD total scores were 86 } 10 and 81 } 9 (p = n.s.) for Placebo and ProSure™, respectively. Postoperative scores were 88 } 12, and 77 } 19 (p = n.s.) The change in score was not different between the two groups (Placebo: +3 } 5; ProSure: -5 } 11). Conclusion: In this very small sample no effect of preoperatively started n-3 enriched nutritional supplements on inflammation or cognitive functions were detected. However, there is a large likelihood of a type II error and more patients need to be included to assess possible beneficial effects of this intervention in elderly patients undergoing elective cardiac surgery. 1 Chandler MJ, et al. Neurology. 2005;65:102-6.

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BACKGROUND: Data on the association between subclinical thyroid dysfunction and fractures conflict. PURPOSE: To assess the risk for hip and nonspine fractures associated with subclinical thyroid dysfunction among prospective cohorts. DATA SOURCES: Search of MEDLINE and EMBASE (1946 to 16 March 2014) and reference lists of retrieved articles without language restriction. STUDY SELECTION: Two physicians screened and identified prospective cohorts that measured thyroid function and followed participants to assess fracture outcomes. DATA EXTRACTION: One reviewer extracted data using a standardized protocol, and another verified data. Both reviewers independently assessed methodological quality of the studies. DATA SYNTHESIS: The 7 population-based cohorts of heterogeneous quality included 50,245 participants with 1966 hip and 3281 nonspine fractures. In random-effects models that included the 5 higher-quality studies, the pooled adjusted hazard ratios (HRs) of participants with subclinical hyperthyroidism versus euthyrodism were 1.38 (95% CI, 0.92 to 2.07) for hip fractures and 1.20 (CI, 0.83 to 1.72) for nonspine fractures without statistical heterogeneity (P = 0.82 and 0.52, respectively; I2= 0%). Pooled estimates for the 7 cohorts were 1.26 (CI, 0.96 to 1.65) for hip fractures and 1.16 (CI, 0.95 to 1.42) for nonspine fractures. When thyroxine recipients were excluded, the HRs for participants with subclinical hyperthyroidism were 2.16 (CI, 0.87 to 5.37) for hip fractures and 1.43 (CI, 0.73 to 2.78) for nonspine fractures. For participants with subclinical hypothyroidism, HRs from higher-quality studies were 1.12 (CI, 0.83 to 1.51) for hip fractures and 1.04 (CI, 0.76 to 1.42) for nonspine fractures (P for heterogeneity = 0.69 and 0.88, respectively; I2 = 0%). LIMITATIONS: Selective reporting cannot be excluded. Adjustment for potential common confounders varied and was not adequately done across all studies. CONCLUSION: Subclinical hyperthyroidism might be associated with an increased risk for hip and nonspine fractures, but additional large, high-quality studies are needed. PRIMARY FUNDING SOURCE: Swiss National Science Foundation.

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The mouse mammary gland develops postnatally under the control of female reproductive hormones. Estrogens and progesterone trigger morphogenesis by poorly understood mechanisms acting on a subset of mammary epithelial cells (MECs) that express their cognate receptors, estrogen receptor alpha (ERalpha) and progesterone receptor (PR). Here, we show that in the adult female, progesterone drives proliferation of MECs in two waves. The first, small wave, encompasses PR(+) cells and requires cyclin D1, the second, large wave, comprises mostly PR(-) cells and relies on the tumor necrosis factor (TNF) family member, receptor activator of NF-kappaB-ligand (RANKL). RANKL elicits proliferation by a paracrine mechanism. Ablation of RANKL in the mammary epithelium blocks progesterone-induced morphogenesis, and ectopic expression of RANKL in MECs completely rescues the PR(-/-) phenotype. Systemic administration of RANKL triggers proliferation in the absence of PR signaling, and injection of a RANK signaling inhibitor interferes with progesterone-induced proliferation. Thus, progesterone elicits proliferation by a cell-intrinsic and a, more important, paracrine mechanism.

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Background: Guidelines of the Diagnosis and Management of Heart Failure (HF) recommend investigating exacerbating conditions, such as thyroid dysfunction, but without specifying impact of different TSH levels. Limited prospective data exist regarding the association between subclinical thyroid dysfunction and HF events. Methods: We performed a pooled analysis of individual participant data using all available prospective cohorts with thyroid function tests and subsequent follow-up of HF events. Individual data on 25,390 participants with 216,247 person-years of follow-up were supplied from 6 prospective cohorts in the United States and Europe. Euthyroidism was defined as TSH 0.45-4.49 mIU/L, subclinical hypothyroidism as TSH 4.5-19.9 mIU/L and subclinical hyperthyroidism as TSH <0.45 mIU/L, both with normal free thyroxine levels. HF events were defined as acute HF events, hospitalization or death related to HF events. Results: Among 25,390 participants, 2068 had subclinical hypothyroidism (8.1%) and 648 subclinical hyperthyroidism (2.6%). In age- and gender-adjusted analyses, risks of HF events were increased with both higher and lower TSH levels (P for quadratic pattern<0.01): hazard ratio (HR) was 1.01 (95% confidence interval [CI] 0.81-1.26) for TSH 4.5-6.9 mIU/L, 1.65 (CI 0.84-3.23) for TSH 7.0-9.9 mIU/L, 1.86 (CI 1.27-2.72) for TSH 10.0-19.9 mIUL/L (P for trend <0.01), and was 1.31 (CI 0.88-1.95) for TSH 0.10-0.44 mIU/L and 1.94 (CI 1.01-3.72) for TSH <0.10 mIU/L (P for trend=0.047). Risks remained similar after adjustment for cardiovascular risk factors. Conclusion: Risks of HF events were increased with both higher and lower TSH levels, particularly for TSH ≥10 mIU/L and for TSH <0.10 mIU/L. Our findings might help to interpret TSH levels in the prevention and investigation of HF.

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High altitude constitutes an exciting natural laboratory for medical research. While initially, the aim of high-altitude research was to understand the adaptation of the organism to hypoxia and find treatments for altitude-related diseases, over the past decade or so, the scope of this research has broadened considerably. Two important observations led to the foundation for the broadening of the scientific scope of high-altitude research. First, high-altitude pulmonary edema (HAPE) represents a unique model which allows studying fundamental mechanisms of pulmonary hypertension and lung edema in humans. Secondly, the ambient hypoxia associated with high-altitude exposure facilitates the detection of pulmonary and systemic vascular dysfunction at an early stage. Here, we review studies that, by capitalizing on these observations, have led to the description of novel mechanisms underpinning lung edema and pulmonary hypertension and to the first direct demonstration of fetal programming of vascular dysfunction in humans.

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Focal therapy is a novel treatment strategy in prostate cancer aiming to treat only the area of the gland harbouring clinically significant disease. The overall objective is to maintain the oncological benefit of active treatment while minimising treatment-related morbidity. Leading centres are currently evaluating various minimally invasive technologies in a rigorous manner. Oncological and functional results in mid-term are encouraging with low rate of urinary incontinence and erectile dysfunction. However, the oncological outcome needs to be evaluated in the long-term in the light of the prolonged natural history of the disease.

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Context: Fibroblast growth factor (FGF) 8 is important for GnRH neuronal development with human mutations resulting in Kallmann syndrome. Murine data suggest a role for Fgf8 in hypothalamo-pituitary development; however, its role in the etiology of wider hypothalamo-pituitary dysfunction in humans is unknown.Objective: The objective of this study was to screen for FGF8 mutations in patients with septo-optic dysplasia (n = 374) or holoprosencephaly (HPE)/midline clefts (n = 47).Methods: FGF8 was analyzed by PCR and direct sequencing. Ethnically matched controls were then screened for mutated alleles (n = 480-686). Localization of Fgf8/FGF8 expression was analyzed by in situ hybridization in developing murine and human embryos. Finally, Fgf8 hypomorphic mice (Fgf8(loxPNeo/-)) were analyzed for the presence of forebrain and hypothalamo-pituitary defects.Results: A homozygous p.R189H mutation was identified in a female patient of consanguineous parentage with semilobar HPE, diabetes insipidus, and TSH and ACTH insufficiency. Second, a heterozygous p.Q216E mutation was identified in a female patient with an absent corpus callosum, hypoplastic optic nerves, and Moebius syndrome. FGF8 was expressed in the ventral diencephalon and anterior commissural plate but not in Rathke's pouch, strongly suggesting early onset hypothalamic and corpus callosal defects in these patients. This was consolidated by significantly reduced vasopressin and oxytocin staining neurons in the hypothalamus of Fgf8 hypomorphic mice compared with controls along with variable hypothalamo-pituitary defects and HPE.Conclusion: We implicate FGF8 in the etiology of recessive HPE and potentially septo-optic dysplasia/Moebius syndrome for the first time to our knowledge. Furthermore, FGF8 is important for the development of the ventral diencephalon, hypothalamus, and pituitary. (J Clin Endocrinol Metab 96: E1709-E1718, 2011)