422 resultados para primary epidermal laminae


Relevância:

20.00% 20.00%

Publicador:

Resumo:

For persons without cardiovascular disease, the benefit of aspirin in primary prevention has been controversial until the recent publication of several major randomized controlled trials. Since then, several medical societies recommend that clinicians discuss aspirin prevention with adults at high cardiovascular risk. Patients with low cardiovascular risk are unlikely to benefit from aspirin, as potential harms (hemorrhagic strokes, gastrointestinal bleedings) may outweigh benefits. Aspirin should be recommended in primary prevention only in patients with a 10-year cardiovascular risk > or = 10% or in diabetic patients aged > or = 40 years with a concomitant cardiovascular risk factor, after assessing contraindications for aspirin and individual's preferences for the risks and benefits associated with aspirin.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The skin is privileged because several skin-derived stem cells (epithelial stem cells from epidermis and its appendages, mesenchymal stem cells from dermis and subcutis, melanocyte stem cells) can be efficiently captured for therapeutic use. Main indications remain the permanent coverage of extensive third degree burns and healing of chronic cutaneous wounds, but recent advances in gene therapy technology open the door to the treatment of disabling inherited skin diseases with genetically corrected keratinocyte stem cells. Therapeutic skin stem cells that were initially cultured in research or hospital laboratories must be produced according strict regulatory guidelines, which ensure patients and medical teams that the medicinal cell products are safe, of constant quality and manufactured according to state-of-the art technology. Nonetheless, it does not warrant clinical efficacy and permanent engraftment of autologous stem cells remains variable. There are many challenges ahead to improve efficacy among which to keep telomere-dependent senescence and telomere-independent senescence (clonal conversion) to a minimum in cell culture and to understand the cellular and molecular mechanisms implicated in engraftment. Finally, medicinal stem cells are expansive to produce and reimbursement of costs by health insurances is a major concern in many countries.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Trust is essential to foster and preserve a long-term relationship between primary care physicians and their patients suffering from chronic diseases. However, this relation remains insufficient to successfully manage more complex situations, such as those of older patients with multiple diseases and disability. For the primary care physician, a significant limitation is the time required to plan and coordinate interventions supplied by different health and social care providers. This article describes a structured approach to support primary care physicians in this difficult task and help them to identify vulnerable older patients requiring to mobilize and coordinate health and social care resources. Current and future resources available to family physicians to complete this challenging task are further described.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Head and neck cancer patients are at high risk for developing second primary tumors. This is known as field cancerization of the aero-digestive tract. In a previous study, we showed that patients with multiple primary tumors were more likely to have p53 mutations in histologically normal mucosae than patients presenting with an isolated tumor. Based on this observation, we postulated that p53 mutations in normal tissue samples of patients bearing a single primary tumor could have a clinical value as a biomarker for the risk of developing second primary tumors. Thirty-five patients presenting with a single primary tumor were followed-up for a median of 51 months (range 1 month to 10.9 years) after biopsies of histologically normal squamous cell mucosa had been analyzed for p53 mutations with a yeast functional assay at the time of the primary tumor. During this follow-up, recurrences and non-sterilization of the primary tumor, occurrence of lymph node metastases, and of second primary tumors were evaluated. Sixteen (45.7%) patients were found to have p53 mutations in their normal squamous cell mucosa, and 19 (54.3%) patients showed no mutation. No relationship was found between p53 mutations and the occurrence of evaluated events during follow-up. Notably, the rate of second primary tumors was not associated with p53 mutations in the normal squamous mucosa. The correlation between p53 mutations in histologically normal mucosae and the incidence of second primary tumors is generally low. The benefit of analyzing p53 mutations in samples of normal squamous cell mucosa in every patient with a primary tumor of the head and neck is doubtful.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Rationale: Human keratinocytes used for transplants are cultivated on a feeder layer which may be composed of autologous human fibroblasts or 3T3 murine fibroblasts. Using the latter method spares 15 additional days of preparation. In this study we investigate the potential presence of residual murine feeder cell contaminants in epidermal cultures prepared for transplantation. Methods: Monolayers of cultured 3T3-J2 murine fibroblasts were treated with 4 μg/mL of mitomycin C (MMC) for 2 h and used to track cell survival kinetics. Using similar 3T3 cells, human keratinocyte cultures were grown following a modified protocol based on the method described by Rheinwald and Green. Cell sheets were mechanically detached and rinsed 4 times following the same procedure used for transplant preparation. The elimination of 3T3 cells during culture was visually tracked using phase contrast microscopy. Epidermal cultures were then dissociated to produce cell suspensions and analyzed by flow cytometry using a murine-specific antibody, CD90, conjugated to a fluorescein isothiocyanate (FITC) marker. Dead cells were identified using 7-amino-actinomysin D (7-AAD) which binds to DNA in permeabilized cells. Results: 3T3 cells treated with MMC display clear morphological signs of apoptosis, disappearing completely in 9-10 days following kinetics similar to 30 Gy gamma irradiated 3T3 cells. Histological analysis of cultured epidermal sheets revealed homogenous keratinocytic tissue with no 3T3 cells. MMC treated and untreated 3T3 cells displayed strong CD90 expression. Cell suspensions obtained from epidermal cultures were, however, negative for that marker. Conclusion: Results obtained demonstrate the absence of contaminating murine 3T3 feeder cells in human keratinocyte cultures. These findings highlight our success in developing cultured human epidermal autografts.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Recent findings have implicated Fas/Fas ligand (FasL) in mediating the death of keratinocytes in spongiotic lesions. We asked whether dying keratinocytes could potentially initiate a protective response of the skin to limit the destruction of the epidermis in the spongiotic areas. In addition to apoptosis, treatment of keratinocyte cultures in vitro with FasL triggers a profound phoshorylation of the epidermal growth factor receptor (EGFR) and of its downstream effectors ERK and protein kinase B (PKB/Akt). Using a variety of inhibitors and blocking antibodies, we demonstrated that: (i) apoptosis is required for the generation of the signal(s) leading to the activation of EGFR, ERK, and Akt; (ii) the activation of EGFR, ERK, and Akt by FasL is indeed mediated by its bona fide receptor Fas; (iii) the activation of EGFR is essential for the subsequent activation of ERK and Akt; and (iv) apoptotic keratinocytes secrete soluble EGFR ligands (including amphiregulin) that are processed from membrane-bound proligand forms by metalloproteinase(s). Our findings demonstrate a potential mechanism for the restriction and repair of spongiotic damage in eczemas.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

OBJECTIVE: The basolateral Na pump drives renotubular reabsorption. In cultured renal cells, mutant adducins, as well as sub-nanomolar ouabain concentrations, stimulate the Na-K pump. METHODS: To determine whether these factors interact and affect Na handling and blood pressure (BP) in vivo, we studied 155 untreated hypertensive patients subdivided on the basis of their plasma endogenous ouabain or alpha-adducin genotype (ADD1 Gly460Trp-rs4961). RESULTS: Under basal conditions, proximal tubular reabsorption and plasma Na were higher in patients with mutated Trp ADD1 or increased endogenous ouabain (P = 0.002 and 0.05, respectively). BPs were higher in the high plasma endogenous ouabain group (P = 0.001). Following volume loading, the increment in BP (7.73 vs. 4.81 mmHg) and the slopes of the relationship between BP and Na excretion were greater [0.017 +/- 0.002 vs. 0.009 +/- 0.003 mmHg/(muEq min)] in ADD1 Trp vs. ADD1 Gly carriers (P < 0.05). BP changes were similar, whereas the slopes of the relationship between BP and Na excretion were lower [0.016 +/- 0.003 vs. 0.008 +/- 0.002 mmHg/(muEq min)] in patients with low vs. high endogenous ouabain (P < 0.05). In patients with high endogenous ouabain, volume loading increased the BP in the ADD1 Trp group but not in the Gly group (P < 0.05). Thus, patients with ADD1 Trp alleles are sensitive to salt and tubular Na reabsorption remains elevated after volume expansion. CONCLUSION: With saline loading, BP changes are similar in high and low endogenous ouabain patients, whereas tubular Na reabsorption increases in the high endogenous ouabain group. Saline loading unmasks differences in renal Na handling in patients with mutant adducin or high endogenous ouabain and exposes an interaction of endogenous ouabain and Trp alleles on BP.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The aims of this review were to describe the case of a patient with debilitating neuroarthropathy of the ankles and feet and reveal a primary systemic (amyloid light chain, AL) amyloidosis and to review the relevant literature concerning the peripheral neuropathy and neuroarthropathy due to amyloidosis. We will emphasize the diagnostic pitfalls and discuss prognosis and treatments of both the peripheral neuropathy and the arthropathy related to AL amyloidosis. This is a descriptive case report of a patient with neuroarthropathy of the lower limbs due to AL amyloidosis. A review and discussion of relevant literature were conducted, based on a PubMed search from 1973 to December 2013. A 51-year-old female was diagnosed with AL amyloidosis after 20 months of investigation of small painful deformities of the feet. Chronic peripheral neuropathy occurs as a manifestation of AL amyloidosis in 25 % of cases. It may exceptionally be complicated by neuroarthropathy. In this case, the paucity of clinical and electrophysiological signs of the neuropathy delayed the diagnosis, leading to a severe arthropathy. The massive destruction of the joints dominated the clinical and the poor functional outcome. Diagnosis of AL amyloidosis should be considered in the presence of a mild peripheral neuropathy and a distal destructive and painless arthropathy. The two key diagnostic procedures are serum protein electrophoresis and nerve biopsy. Delay in treatment worsens the prognosis.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The epidermal growth factor (EGF) receptor/ligand system stimulates multiple pathways of signal transduction, and is activated by various extracellular stimuli and inter-receptor crosstalk signaling. Aberrant activation of EGF receptor (EGFR) signaling is found in many tumor cells, and humanized neutralizing antibodies and synthetic small compounds against EGFR are in clinical use today. However, these drugs are known to cause a variety of skin toxicities such as inflammatory rash, skin dryness, and hair abnormalities. These side effects demonstrate the multiple EGFR-dependent homeostatic functions in human skin. The epidermis and hair follicles are self-renewing tissues, and keratinocyte stem cells are crucial for maintaining these homeostasis. A variety of molecules associated with the EGF receptor/ligand system are involved in epidermal homeostasis and hair follicle development, and the modulation of EGFR signaling impacts the behavior of keratinocyte stem cells. Understanding the roles of the EGF receptor/ligand system in skin homeostasis is an emerging issue in dermatology to improve the current therapy for skin disorders, and the EGFR inhibitor-associated skin toxicities. Besides, controlling of keratinocyte stem cells by modulating the EGF receptor/ligand system assures advances in regenerative medicine of the skin. We present an overview of the recent progress in the field of the EGF receptor/ligand system on skin homeostasis and regulation of keratinocyte stem cells.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

OBJECTIVE: To compare the prevalence of intermediate and premutation FMR1 alleles in women with occult primary ovarian insufficiency (oPOI) and in controls. DESIGN: Observational study. SETTING: Division of Infertility and Service of Genetic Medicine, Geneva University Hospitals. PATIENT(S): The study group consisted of 27 infertile women with oPOI referred by infertility specialists for FMR1 testing in 2005-6 because of unexplained poor response to controlled ovarian hyperstimulation or altered hormonal profiles. The control group consisted of 32 women undergoing genetic testing for conditions unrelated to mental retardation or ovarian function. The DNA samples were anonymized. INTERVENTION(S): In the study group, data were collected concerning reproductive/family history, hormonal markers, possible fertility treatment outcomes, and results of karyotype and FMR1 testing. In the control group, FMR1 gene testing was done. The only clinical data available in controls were sex and indication for genetic testing. MAIN OUTCOME MEASURE(S): Distribution of FMR1 alleles. RESULT(S): Six (22%) of 27 women with oPOI had FMR1 alleles of >40 repeats (intermediate to premutation range), compared with one (3%) of 32 controls. CONCLUSION(S): These results suggest that women with oPOI might be at risk of carrying alleles in the intermediate and premutation range.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Background We previously reported the results of a phase II study for patients with newly diagnosed primary central nervous system lymphoma treated with autologous peripheral blood stem-cell transplantation (aPBSCT) and response-adapted whole-brain radiotherapy (WBRT). Now, we update the initial results. Patients and methods From 1999 to 2004, 23 patients received high-dose methotrexate. In case of at least partial remission, high-dose busulfan/thiotepa (HD-BuTT) followed by aPBSCT was carried out. Patients refractory to induction or without complete remission after HD-BuTT received WBRT. Eight patients still alive in 2011 were contacted and Mini-Mental State Examination (MMSE) and the European Organisation for Research and Treatment of Cancer quality-of-life questionnaire (QLQ)-C30 were carried out. Results Of eight patients still alive, median follow-up is 116.9 months. Only one of nine irradiated patients is still alive with a severe neurologic deficit. In seven of eight patients treated with HD-BuTT, health condition and quality of life are excellent. MMSE and QLQ-C30 showed remarkably good results in patients who did not receive WBRT. All of them have a Karnofsky score of 90%-100%. Conclusions Follow-up shows an overall survival of 35%. In six of seven patients where WBRT could be avoided, no long-term neurotoxicity has been observed and all patients have an excellent quality of life.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The highly amiloride-sensitive epithelial sodium channel ENaC is well known to be involved in controlling whole body sodium homeostasis and lung liquid clearance. ENaC expression has also been detected in the skin of amphibians and mammals. Mice lacking ENaC expression lose rapidly weight associated with an epidermal barrier defect that develops following birth. This dehydration is accompanied with a highly abnormal lipid matrix composition and an impaired skin surface acidification. This strongly suggests a role of ENaC in the maturation of barrier function rather than in the prenatal generation of the barrier, and may be as such an important modulator for skin hydration. In parallel, gene targeting experiments of regulators of ENaC activity, membrane serine proteases, also termed channel activating proteases, like CAP1/Prss8 and matriptase/MT-SP1 by themselves have been shown to be crucial for the epidermal barrier function. In our review, we mainly focus on the role of ENaC and its regulators in the skin and discuss their importance in the epidermal permeability barrier function.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

BACKGROUND: Primary ciliary dyskinesia (PCD) is characterised by recurrent infections of the upper respiratory airways (nose, bronchi, and frontal sinuses) and randomisation of left-right body asymmetry. To date, PCD is mainly described with autosomal recessive inheritance and mutations have been found in five genes: the dynein arm protein subunits DNAI1, DNAH5 and DNAH11, the kinase TXNDC3, and the X-linked retinitis pigmentosa GTPase regulator RPGR. METHODS: We screened 89 unrelated individuals with PCD for mutations in the coding and splice site regions of the gene DNAH5 by denaturing high performance liquid chromatography (DHPLC) and sequencing. Patients were mainly of European origin and were recruited without any phenotypic preselection. RESULTS: We identified 18 novel (nonsense, splicing, small deletion and missense) and six previously described mutations. Interestingly, these DNAH5 mutations were mainly associated with outer + inner dyneins arm ultrastructural defects (50%). CONCLUSION: Overall, mutations on both alleles of DNAH5 were identified in 15% of our clinically heterogeneous cohort of patients. Although genetic alterations remain to be identified in most patients, DNAH5 is to date the main PCD gene.