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Amanda M. Nelson Zhaoyuan Cong Samantha L. Gettle Amy L. Longenecker Michal Kidacki Joslyn S. Kirby David R. Adams Douglas B. Stairs Frederick W. Danby 《Experimental dermatology》2019,28(7):867-871
Hidradenitis suppurativa (HS) is a chronic, inflammatory skin disease affecting the pilosebaceous units in the axilla, groin and buttocks. While the pathogenesis of HS is not clear, mechanical stress exacerbates HS. In this study, we aimed to determine whether intracellular adhesive junctions may be aberrant in HS patient skin. Strikingly, we observed loss of E‐cadherin and p120ctn protein expression, two key adherens junction proteins, in ~85% of HS severe skin lesions. Moreover, loss of protein expression was apparent in non‐lesional skin from HS patients and the degree of loss positively correlated with HS Hurley Stage of disease. E‐cadherin expression was unaltered in other inflammatory skin conditions including chronic wound epithelium, atopic dermatitis, and acne vulgaris compared with healthy skin suggesting that its loss may be uniquely relevant to HS pathogenesis. A complete loss of α‐catenin, β‐catenin and ZO‐1 was not observed; however, some cytoplasmic staining of the catenins was noted in HS epithelium. We also demonstrated diminished desmosome size in HS lesional skin. Overall, our data suggested that loss of adherens junction proteins and diminished desmosome size in HS skin contributes to the skin's inability to withstand mechanical stress and provides rationale as to why mechanical stress exacerbates HS symptoms. 相似文献
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Periosteal new bone formation (PNBF) is a common finding in a large spectrum of diseases. In clinical practice, the morphology and location of periosteal lesions are frequently used to assist in the differential diagnosis of distinct bone conditions. Less commonly reported is the presence of PNBF on the ribs. This contrasts with the data retrieved from the study of skeletonized human remains that shows a high frequency of cases and a strong, albeit not specific, association between periosteal rib lesions and pulmonary conditions (e.g. tuberculosis). Despite that, an overall disagreement regarding the specificity and non‐specificity of periosteal reactions exists in the study of dry bone remains. The insufficient number of clinical models exploring the morphology and the pathophysiology of PNBF's and the lack of systematic studies of pathological samples with a known diagnosis are claimed as major reasons for the disagreements. This study aimed to describe and compare the macroscopic and the histomorphologic appearance of periosteal rib lesions and to discuss their usefulness as diagnostic indicators. To pursue this goal, an assemblage of 13 rib samples (males = 11, females = 2, mean age‐at‐death = 36.6 years old) was collected from the Luis Lopes Skeletal Collection (Museu Nacional de História Natural e da Ciência, Universidade de Lisboa, Portugal). The assemblage belongs to individuals who died from pulmonary‐TB (group 1), non‐TB pulmonary infections (group 2) and other conditions (group 3). Prior to sample preparation, the ribs were visually inspected and the PNBF described according to its thickness, the degree of cortical integration and the type of new bone formed (e.g. woven, lamellar or both). After sampling, each bone sample was prepared for histological analysis under plane and polarized light microscopy. Macroscopically, the results showed no differences in the new bone composition between cause‐of‐death groups. Only slight differences in the degree of cortical integration, which was most frequently classified as mild to high in the pulmonary‐TB group, were observed. Histologically, no distinguishing features were identified by pathological group. However, new bone microarchitectures were observed compatible with (1) acute, fast‐growing processes (e.g. spiculated reactions), (2) long‐standing processes with a rapid bone formation (e.g. appositional layering of bone) and/or (3) chronic, slow‐growing processes (e.g. layers of compact lamellae). To some extent, these distinct rates of disease progression resonate with the cause‐of‐death listed for some individuals. Despite the small sample size, the results of this investigation are in agreement with previous studies, according to which the macroscopic and histological appearance of periosteal formations are not specific for a particular pathological conditions. Nevertheless, the results support the conclusion that the morphology of periosteal lesions is a good biological indicator for inferring the rate of progression and duration of pathological processes. This study provides important reference data regarding the histomorphology of periosteal lesions that can be used for comparative purposes, as well as to narrow down the differential diagnosis in unidentified skeletal remains. 相似文献
105.
Paulo Roberto Lima Falco do Vale Sheila Cerqueira Hudson P. Santos Beth P. Black Evanilda Souza de Santana Carvalho 《Nursing inquiry》2019,26(1)
The rapidly increasing number of cases of Zika virus and limited understanding of its congenital sequelae (e.g., microcephaly) led to stories of fear and uncertainty across social media and other mass communication networks. In this study, we used techniques generic to netnography, a form of ethnography, using Internet‐based computer‐mediated communications as a source of data to understand the experience and perceptions of families with infants diagnosed with Zika‐related microcephaly. We screened 27 YouTube? videos published online between October 2015 and July 2016, during which the Zika epidemic started, peaked, and declined. We identified three themes: (a) experiencing the news of a diagnosis of Zika‐associated microcephaly; (b) experiencing feelings and expectations of the ‘imperfect’ child; and (c) seeking to understand microcephaly to care for the child. We found that families experienced distressing feelings of shock, sadness, hopelessness, and pain, while dealing with emerging and sometimes conflicting information being transmitted by news outlets, uncertainty about the child's health, and healthcare providers’ lack of clarity to guide the family members. The ‘unknown’ factor of ZIKA was an additional stressful factor in the experience of the families. 相似文献
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《Clínica e investigación en ginecología y obstetricia》2019,46(3):134-141
The increasing prevalence of obese women of childbearing age is a public and social health crisis. Contraception is a key issue in women with obesity. Obese women have a sexual activity no different from women of normal weight, and the use of contraception is considered less effective, as there is a higher risk of having an unwanted pregnancy. Due to a variety of metabolic disorders, obesity is a cardiovascular risk factor that can increase when combined with hormonal contraception. All these factors should be considered when choosing a contraceptive method in an obese woman. The objective of this review is to evaluate the risk-benefit of each type of available contraception, and the problem of contraception after bariatric surgery, in order to provide doctors with a practical guide on the use of oral contraceptive pills in obese women. 相似文献
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Members of the Acomys genus, known as spiny mice, are unique among mammals in being perfectly capable of regenerating large areas of skin that have been removed. During this regenerative process hairs, sebaceous glands, erector pili muscles, adipocytes and the panniculus carnosus all regenerate and the dermis does not scar. We review here the processes that the epidermis and the individual components of the dermis undergo during spiny mouse regeneration as well as the molecules that have been identified as potentially important in regeneration. We then relate this to what has been proposed as playing a role in studies from the laboratory mouse, Mus musculus. Differences in the immune systems of spiny mice and laboratory mice are also highlighted as this is suggested to play a part not only in the perfect wound healing that embryos display but also in regeneration in lower vertebrates. 相似文献
110.
《Nutrition, metabolism, and cardiovascular diseases : NMCD》2019,29(7):653-664
Background and aimEffects of whole egg consumption on cardiovascular diseases (CVD) risk in the middle-aged and older population remain unclear due to inconsistent findings from observational and randomized controlled trials (RCTs). This meta-analysis aimed to assess the impacts of whole egg and egg category (whole eggs versus egg substitutes) intake quantity on CVD risk factors from systematically searched RCTs. Egg substitutes were hypothesized to have minimal effects of the blood lipid and lipoprotein profile as they are void of dietary cholesterol.Methods and resultsAs many as 434 studies identified from PubMed, Cochrane Library, CINAHL and Medline (Ovid) databases were screened and data were extracted from 8 selected RCTs. Quality of the selected studies were assessed and the overall effect sizes of weighted mean differences (WMD) were calculated using a random effects model. Non-differential effects in blood pressures, lipids and lipoproteins were observed when >4 whole eggs/week compared to ≤4 whole eggs/week were consumed. Intake of >4 whole eggs/week compared to equivalent amounts of egg substitutes caused greater elevations in blood total cholesterol (WMD: 0.198 mmol/L; 95% CIs: 0.056, 0.339), HDL cholesterol (WMD: 0.068 mmol/L; 95% CIs: 0.006, 0.130) and LDL cholesterol (WMD: 0.171 mmol/L; 95% CIs: 0.028, 0.315) but did not differentially affect triglycerides concentration.ConclusionOverall, the results support the notion that quantity of whole egg intake does not affect CVD risk factors and consuming egg substitutes may also be beneficial compared to whole eggs on lowering CVD risk in the middle-aged and older population. 相似文献