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11.
Hyper-pigmentation is a common, acquired dermatological skin-disorder manifesting and identifiable as irregular brown or greyish-brown facial discolouration, and sometimes referred to as melanosis, melasma or hypermelanosis. Purpose and Objective: To identify the site of melanin deposition in skin-layers regarding facial hyper-pigmentation, based on a histological study of full-thickness skin-facial biopsies in aged Caucasian-cadavers. Hypothesis: Recalcitrant hyper-pigmentation, is chiefly characterised by hyper-melanosis restricted to the dermal-layer of the integument. Method: The histological features of facial hyper-pigmentation and solar-lentigenes were evaluated in a pilot-study of 5-randomly selected Caucasian-cadavers with pigmentation (15 facial biopsies), ranging in age between 75 and 102 years (mean 77-years). Selection-criteria included, both genders, age 〉 75, focal and confluent hyper-pigmented lesions, involving sun-exposed areas of skin (centrifacial, scalp, malar, mandibular and cervical). Study groups included (Grp-1: Control skin-histology in otherwise normal aged, human-cadavers; Grp-2: Histology of pigmented facial skin-lesions in man; Grp-3: Comparative histological skin-controls in non-human primates). No obvious hepatic disease was evident in the cohort studied. Twenty-five histological controls were obtained from non-pigmented areas. Histological evaluation of full-thickness skin-biopsies (including the lesion, edge and peri-]esion skin), was under a Leitz~-light-microscope, and staining included H&E, Masson-trichrome, Masson-fontana, Alcian-blue and Verhoef technology. Histological-scoring used was on histological deposition of melanin in skin-layers: epidermal, dermal, mixed, and indeterminate melanin-deposition (score 1-4). Controls included cadaveric skin-biopsies of human races of colour and non-human primate, Cercopethicus Aethiops (latter is known to have predominantly dermal-melanin deposition). Pigmented and non-pigmented areas were compared in both species. Results: The majority of clinically visible individual and confluent areas of hyper-pigmentation studied were maeroscopically present on the forehead, frontal scalp in hair-receded cadavers, molar and temporal zones. Histologically, documented features of age-related changes without pigment were present in almost all the embalmed cadaver-skins, with a melanin-score of 1. Computer enhanced skin geometry and biometrics confirmed the presence of an aged-skin, pigmentation and features of solar damage. The human embalmed-tissue was well preserved and minimal autolytic changes were present. Special stains of full-thickness biopsies (Masson-Fontana), showed that melanin in the subhuman-primate is lodged in the deep dermis (reticular dermis), within the extra-cellular matrix (ECM) and superficial to the hypodermal adipose-tissue (melanin-score 3). Fifteen pigmented lesions studied in five (5) aged-cadavers (forehead, molar and mandibular areas) all showed predominantly epidermal-deposition of melanin in the basal, suprabasal and stratum corneum with tiny focal areas of dermal melanosis in single-cell macrophages in the papillary-dermis but not reticular-dermis (melanin-score 2). A melanin-deposition localization ratio of epidermis to dermis was approximately 98 to 2% in cadavers with hyper-pigmentation. Conclusion: The skin-strata localization of the melanin with regards hyper-pigmentation of the face and forehead in this aged, human adult Caucasian, cadaveric-study, was predominantly in the epidermis and sparse in the papillary dermis.  相似文献   
12.
Although adult skeletal muscle is composed of fully differentiated fibers, it retains the capacity to regenerate in response to injury and to modify its contractile and metabolic properties in response to changing demands. The major role in the growth, remodeling and regeneration is played by satellite cells, a quiescent population of myogenic precursor cells that reside between the basal lamina and plasmalemma and that are rapidly activated in response to appropriate stimuli. However, in pathologic conditions or during aging, the complete regenerative program can be precluded by fibrotic tissue formation and resulting in functional impairment of the skeletal muscle. Our study, along with other studies, demonstrated that although the regenerative program can also be impaired by the limited proliferative capacity of satellite cells, this limit is not reached during normal aging, and it is more likely that the restricted muscle repair program in aging is presumably due to missing signals that usually render the damaged muscle a permissive environment for regenerative activity.  相似文献   
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15.

Objective:

To evaluate quantitative measurements of background parenchymal enhancement (BPE) on breast MRI and compare them with observer-based scores.

Methods:

BPE of 48 patients (mean age: 48 years; age range: 36–66 years) referred to 3.0-T breast MRI between 2012 and 2014 was evaluated independently and blindly to each other by two radiologists. BPE was estimated qualitatively with the standard Breast Imaging Reporting and Data System (BI-RADS) scale and quantitatively with a semi-automatic and an automatic software interface. To assess intrareader agreement, MRIs were re-read after a 4-month interval by the same two readers. The Pearson correlation coefficient (r) and the Bland–Altman method were used to compare the methods used to estimate BPE. p-value <0.05 was considered significant.

Results:

The mean value of BPE with the semi-automatic software evaluated by each reader was 14% (range: 2–79%) for Reader 1 and 16% (range: 1–61%) for Reader 2 (p > 0.05). Mean values of BPE percentages for the automatic software were 17.5 ± 13.1 (p > 0.05 vs semi-automatic). The automatic software was unable to produce BPE values for 2 of 48 (4%) patients. With BI-RADS, interreader and intrareader values were κ = 0.70 [95% confidence interval (CI) 0.49–0.91] and κ = 0.69 (95% CI 0.46–0.93), respectively. With semi-automated software, interreader and intrareader values were κ = 0.81 (95% CI 0.59–0.99) and κ = 0.85 (95% CI 0.43–0.99), respectively. BI-RADS scores correlated with the automatic (r = 0.55, p < 0.001) and semi-automatic scores (r = 0.60, p < 0.001). Automatic scores correlated with the semi-automatic scores (r = 0.77, p < 0.001). The mean percentage difference between automatic and semi-automatic scores was 3.5% (95% CI 1.5–5.2).

Conclusion:

BPE quantitative evaluation is feasible with both semi-automatic and automatic software and correlates with radiologists'' estimation.

Advances in knowledge:

Computerized BPE quantitative evaluation is feasible with both semi-automatic and automatic software. Computerized BPE quantitative scores correlate with radiologists'' estimation.  相似文献   
16.

Background

Phosphodiesterase 5 inhibitors (PDE5-Is) are a mainstay in the therapy of erectile dysfunction (ED). The primary end point of clinical efficacy, both in clinical studies and normal practice, is represented by the International Index of Erectile Function (IIEF).

Objective

To evaluate if platelet cyclic guanosine monophosphate (cGMP) could represent a valuable marker for PDE5-I activity in ED.

Design, setting, and participants

The study enrolled 46 patients with psychogenic, organic, and mixed ED (20–71 yr of age; IIEF score <26). Patients were randomized to 6 wk of vardenafil, 5 mg/d at bedtime, or placebo.

Intervention

All patients donated two blood samples, one before starting the protocol and the second after 6 wk of treatment.

Measurements

Platelet cGMP was measured in both placebo and vardenafil groups. All the patients completed the IIEF-Erectile Function (EF) domain and the sexual encounter profile (SEP) and underwent visual sexual stimulation (VSS) coupled with Rigiscan. All the measurements were performed prior to starting the protocol and after the 6 wk of treatment.

Results and limitations

Platelet cGMP production was significantly (p < 0.05) elevated in patients taking 5 mg vardenafil versus placebo. Vardenafil was not superior to placebo in improving IIEF-EF and SEP scores. Conversely, VSS-Rigiscan revealed a significant amelioration (p < 0.028) in the vardenafil group versus placebo. The changes in platelet cGMP level correlated well with VSS-Rigiscan (p = 0.0037) but not with IIEF-EF and SEP.

Conclusions

Platelet cGMP could represent a relatively simple, reliable, and objective biomarker of PDE5-I activity in ED clinical studies. Larger clinical studies are needed to further validate the use, utility, and limits of this assay.  相似文献   
17.
Apomorphine is used in the erectile dysfunction therapy and its action has been ascribed to the stimulation of central dopamine receptor. At the present stage, very little is known about the peripheral action of apomorphine on human corpus cavernosum (HCC). We have investigated the peripheral action of apomorphine and the role of dopamine receptors in HCC. We here demonstrate that both D1 and D2 receptors were expressed in the HCC, D1 receptors were two-fold more abundant than D2 and that both receptors were mainly localized on the smooth muscle cell component. Apomorphine in vitro exerted an anti-alpha1 adrenergic activity in human cavernosal strips since it prevented contraction induced by phenylephrine (PE), but not by U46619 or endothelin. Apomorphine elicited endothelium-independent and concentration-dependent relaxation of the strips contracted by PE, U46619 or endothelin. The EC50 values (microM) for apomorphine, in the presence and absence of endothelium, were 51.0+/-16 and 16.0+/-14, 120+/-19 and 150+/-18, 59.0+/-15 and 140+/-50 on PE-, U46619- or endothelin-induced contraction, respectively. Selective dopamine receptor agonist A-68930 (D1-like), but not quinpirole (D2-like), caused concentration-dependent relaxation of the cavernosal strips, which was partially prevented by endothelium removal or by treatment with an inhibitor of nitric oxide (NO) synthase. In conclusion, we show that (1) apomorphine has a peripheral relaxant direct effect as well as an antiadrenergic activity, (2) HCC possesses more D1-like (D1 and D5) than D2-like (D2, D3 and D4) receptors, (3) both D1- and D2-like receptors are mainly localized on smooth muscle cells and (4) the relaxant activity is most probably mediated by D1-like receptor partially through NO release from endothelium.  相似文献   
18.
This statement, focused on melanonychia and nail plate dermoscopy, is intended to guide medical professionals working with melanonychia and to assist choosing appropriate management for melanonychia patients. The International Study Group on Melanonychia was founded in 2007 and currently has 30 members, including nail experts and dermatopathologists with special expertise in nails. The need for common definitions of nail plate dermoscopy was addressed during the Second Meeting of this Group held in February 2008. Prior to this meeting and to date (2010) there have been no evidence-based guidelines on the use of dermoscopy in the management of nail pigmentation.  相似文献   
19.
Lens opacities in adults in Pakistan: prevalence and risk factors   总被引:1,自引:0,他引:1  
PURPOSE: To investigate the prevalence and risk factors for lens opacity (LO) amongst a nationally representative sample of the adult population of Pakistan. METHODS: This national study of blindness and visual impairment (adults > or =30 years) used multistage, stratified, cluster random sampling. Grading of LO was conducted using the Mehra/Minassian classification system. LO, partly or wholly obscuring the red reflex, or previous cataract surgery were indicators of opacity. RESULTS: 16,402 (94.7%) adults were included in this analysis (study conducted 2002-2003). A total of 4,096 (standardized prevalence 20.9%, 95%CI: 20.3, 21.5%) adults were found to have LO. The highest prevalence of LO was found in Punjab province (22.2%), the lowest in Balochistan Province (18.0%). Significant positive associations were increasing age (multivariable odds ratio (OR) 3.2: 95%CI: 3.1, 3.4), hypertension (OR 1.2, 95%CI: 1.1, 1.3), history of diabetes (OR 2.6: 95%CI 2.0, 3.2) and smoking (OR 1.3: 95%CI: 1.1, 1.5). Higher body mass index (BMI) (OR 0.8: 95%CI 0.7, 0.9, heavy vs. normal BMI) and attendance to school (OR 0.6: 95%CI: 0.5, 0.8) were associated with lower risk of LO. Individuals in districts classified as hot were at significantly increased risk (OR 1.3: 95%CI: 1.1, 1.5), and those in wet districts (> 600 mm annual rainfall) had lower odds than individuals living in dry districts (OR 0.7: 95%CI: 0.6, 0.8). CONCLUSIONS: Almost a fifth of the adult population had LO. Significant positive associations were age, smoking status, hypertension, diabetes, and increased deprivation level. Protective factors included high BMI and educational achievement. The climatic associations offer novel hypothesis for further research into cataractogenesis.  相似文献   
20.
Reliable flow cytometric analysis of normal and diseased skin requires pure epidermal single-cell suspensions. Several methods to separate the dermis from the epidermis are available. The proteolytic enzyme thermolysin separates the epidermis from the dermis at the lamina lucida and therefore permits reliable dermoepidermal separation. In the present study an optimized cell isolation procedure using thermolysin and trypsin is described, which is particularly suitable for punch biopsies. A 16–20-h (overnight) incubation of biopsies taken from normal and hyperproliferative skin with thermolysin (0.5 mg/ml) at 4°C produced a selective separation of the dermis and epidermis. After a 30-min trypsin incubation (0.25 mg/ml) at 37°C a cell suspension was produced which was characterized by minimal cell damage (cellular debris and clumps), a high recovery of basal cells and high quality DNA histograms. Furthermore, dermal contamination was very low. The thermolysin-trypsin separation methodology followed by triple-labelling flow cytometry provided a precise quantification of the percentage of keratin 10-positive cells, vimentin-positive cells and cells in S and G2M phases. Proliferative activity was selectively measured in the basal, the suprabasal and the non-keratinocyte compartment at various time intervals during epidermal regeneration after adhesive tape stripping. In contrast to the non-keratinocytes, the percentage of cells in S and G2M phases in the basal keratinocytes and in the suprabasal compartment increased 44–48 h after stripping. The increased proliferation following tape stripping was paralleled by an increased invasion of vimentin-positive cells into the epidermis and preceded by a decreased number of keratin 10-positive cells. Thermolysin-trypsin separation followed by three-colour flow cytometry permits a highly selective characterization of normal and hyperproliferative epidermis.  相似文献   
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