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71.

Background

The levels and clinical relevance of Th17 cells and other interleukin-17-producing cells have not been analyzed in chronic lymphocytic leukemia. The objective of this study was to quantify blood and tissue levels of Th17 and other interleukin-17-producing cells in patients with this disease and correlate blood levels with clinical outcome.

Design and Methods

Intracellular interleukin-17A was assessed in blood and splenic mononuclear cells from patients with chronic lymphocytic leukemia and healthy subjects using flow cytometry. Interleukin-17A-producing cells were analyzed in formalin-fixed, paraffin-embedded spleen and lymph node sections using immunohistochemistry and immunofluorescence.

Results

The absolute numbers of Th17 cells in peripheral blood mononuclear cells and the percentages of Th17 cells in spleen cell suspensions were higher in patients with chronic lymphocytic leukemia than in healthy subjects; in six out of eight paired chronic lymphocytic leukemia blood and spleen sample comparisons, Th17 cells were enriched in spleen suspensions. Circulating Th17 levels correlated with better prognostic markers and longer overall survival of the patients. Two “non-Th17” interleukin-17-expressing cells were identified in chronic lymphocytic leukemia spleens: proliferating cells of the granulocytic lineage and mature mast cells. Granulocytes and mast cells in normal spleens did not express interleukin-17. Conversely, both chronic lymphocytic leukemia and healthy lymph nodes contained similar numbers of interleukin-17+ mast cells as well as Th17 cells.

Conclusions

Th17 cells are elevated in chronic lymphocytic leukemia patients with better prognostic markers and correlate with longer survival. Furthermore, non-Th17 interleukin-17A-expressing cells exist in chronic lymphocytic leukemia spleens as maturing granulocytes and mature mast cells, suggesting that the microenvironmental milieu in leukemic spleens promotes the recruitment and/or expansion of Th17 and other IL-17-expressing cells. The pathophysiology of Th17 and non-Th17-interleukin-producing cells in chronic lymphocytic leukemia and their distributions and roles in this disease merit further study.  相似文献   
72.
The majority of people throughout the world show extreme preference for the right hand. We studied lateral bias depicted in ancient Indian sculptures dating between the 7th and 9th centuries ad. A total of 288 sculptures were selected from various excavation sites/museums and the frequencies were computed on 13 different criteria in order to see the preferential bias for hand depicted in sculptures of male and female figures. The findings are discussed in the light of Hindu mythology and rituals.  相似文献   
73.
Laser speckle contrast imaging (LSCI) is a high-resolution and high contrast optical imaging technique often used to characterize hemodynamic changes in short-term physiological experiments. In this study, we demonstrate the utility of LSCI for characterizing microvascular remodeling and hemodynamic changes during wound healing angiogenesis in vivo. A 2 mm diameter hole was made in the mouse ear and the periphery of the wound imaged in vivo using LSCI over 12 days. We were able to visualize and quantify the vascular and perfusion changes that accompanied wound healing in the microenvironment proximal to the wound, and validated these changes with histology. We found that consistent with the stages of wound healing, microvessel density increased during the initial inflammatory phase (i.e., day 0–3), stayed elevated through the tissue formation phase (i.e., until day 7) and returned to baseline during the tissue remodeling phase (i.e., by day 12). Concomitant “wide area mapping” of blood flow revealed that tissue perfusion in the wound periphery initially decreased, gradually increased from day 3–7, and subsided as healing completed. Interestingly, some regions exhibited a reestablishment of tissue perfusion approximately 6 days earlier than the ~18 days usually reported for the long term remodeling phase. The results from this study demonstrate that LSCI is an ideal platform for elucidating in vivo changes in microvascular hemodynamics and angiogenesis, and has the potential to offer invaluable insights in a range of disease models involving abnormal hemodynamics, such as diabetes and tumors.  相似文献   
74.
Ethanol is widely used in various pharmaceutical and cosmetic formulations in order to enhance skin penetration of active ingredients. While it is well known that ethanol partitions into the skin and enhances the permeation of both polar and nonpolar molecules, the exact mechanisms by which it enhances skin permeability are not fully understood. Several mechanisms have been proposed including lipid extraction from the stratum corneum (SC), fluidisation of SC lipid bilayer, alteration of SC protein conformation and enhancement of the drug solubility in the SC lipids. In this study, we performed molecular dynamics (MD) simulations of SC lipid bilayers comprised of an equimolar mixture of ceramides, cholesterol and free fatty acid in the presence of aqueous mixtures of ethanol. Various unrestrained MD simulations were performed in the presence of aqueous ethanol solution at molar ratios (x) ranging from x = 0 to x = 1. It was found that ethanol enhances bilayer permeability by dual actions (a) extraction of the skin lipids and (b) enhancing the mobility of lipid chains. Ethanol''s permeation enhancing effect arises from its superior ability to form hydrogen bonds with headgroup atoms of skin lipids. Further, the free energy of extraction of ceramides (CER) and fatty acids (FFA) from the lipid bilayer was studied using umbrella sampling simulations. The free energy of extraction of CER was found to be much higher compared to FFA for all ethanol concentrations which shows that CER are difficult to extract as compared to FFA. Finally, the permeation of benzoic acid drug molecules through the skin lipid bilayer is shown in presence of ethanol molecules. It was found that ethanol selectively targets the FFA of the skin lipid bilayer and extracts it out of the lipid bilayer within few microseconds. Further, ethanol penetrates inside the lipid layer and creates the channels from which drug molecules can easily cross the lipid layer. Our observations (both in unrestrained and umbrella sampling simulations) are consistent with the experimental findings reported in the literature. The simulation methodology could be used for design and testing of permeation enhancers (acting on skin SC lipid lamella) for topical and transdermal drug delivery applications.

Concentration dependent action of mechanism of ethanol on skin SC lipid barrier.  相似文献   
75.

Introduction and hypothesis

A significant proportion of patients develop voiding dysfunction after midurethral tape (MUT) insertion, which reduces patient satisfaction. The study’s purpose was to identify predictive factors of voiding dysfunction after a retropubic MUT procedure.

Methods

This was a retrospective study of 100 patients who underwent only a retropubic MUT procedure between January 2010 and December 2011. Early voiding dysfunction was defined when patients required a Foley catheter within 48 h. Data including demographic information, urogenital symptoms, previous surgery, preoperative uroflowmetry and urodynamic parameters were analysed using SPSS v22. Univariate analysis of all demographic variables was performed; those significant at 10 % were entered into a multivariate logistic regression.

Results

Fourteen patients required Foley catheter insertion, with a median age of 58 years (26–83 years), median BMI 28 kg/m2 (20–48 kg/m2), and median parity 2 (0–4). Univariate analysis revealed peak flow rate <15 ml/s (OR 3.79; 1.07, 13.4; p?=?0.046), bladder capacity (p?=?0.044), stress incontinence versus mixed or urge incontinence (p?=?0.064) and previous surgery (OR 4.39; 1.34, 14.41; p?=?0.015) to be associated with voiding dysfunction. Multivariate analysis showed only previous pelvic floor surgery to be independently associated (OR 3.76; 1.14, 12.23, p?=?0.029).

Conclusions

Only previous pelvic-floor surgery was found to be a strong predictive factor of voiding dysfunction. The rate of voiding dysfunction was similar to those of published data. Previous studies revealed different predictive factors. A larger cohort is needed to provide a definite answer. Those with previous surgery appear to be those most at risk and pre-surgical counselling for these women could be suggested.
  相似文献   
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79.
Reported is a case of seven-year-old, migrant from Bihar state, infested with Fasciolopsis buski Strongyloides stercoralis Ascaris lumbricoides, Trichuris trichiura and Ankylostoma duodenale in feces. Patient responded to treatment with piperazine, thiabendazole and albendazole, the importance of considering multiple and non-endemicparasite infestations in migrant of poor socio-economic background is emphasized.  相似文献   
80.
BACKGROUND: Histopathological examination of products of conception from miscarriages is part of routine clinical practice. The extent of additional clinically relevant information provided by this investigation in the setting of recurrent spontaneous abortion remains uncertain. METHODS: Review of the literature was performed to identify studies reporting on findings of histological examination of routinely obtained products of conception in the setting of recurrent spontaneous abortion. The initial search identified 312 potential references, but 300 were excluded on further examination due to lack of data on specific histopathological findings in routine products of conception specimens from patients with recurrent spontaneous abortion. The 12 included studies indicated that such examination may identify hydatidiform moles, villous dysmorphic features suggesting fetal aneuploidy, chronic histiocytic intervillositis (CHI) and massive perivillous fibrin deposition and impaired trophoblast invasion. However, in most cases, morphological assessment cannot reliably determine the cause of the miscarriage or distinguish recurrent from sporadic miscarriage. Studies reporting on the use of additional immunohistochemical methods do not currently provide additional clinically useful diagnostic or prognostic information. CONCLUSION: Routine histological examination of products of conception in the setting of recurrent spontaneous abortion can provide important clinical information in a minority of cases.  相似文献   
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