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81.
The kinetics of gene expression associated with the development of cutaneous graft-versus-host disease (GVHD) were examined in a mouse model of MHC-matched allogeneic hematopoietic stem cell transplantation. Ear skin was obtained from recipient mice with or without GVHD between 7 and 40 days after transplantation for histopathological analysis and gene expression profiling. Gene expression patterns were consistent with early infiltration and activation of CD8(+) T and mast cells, followed by CD4(+) T, natural killer, and myeloid cells. The sequential infiltration and activation of effector cells correlated with the histopathological development of cutaneous GVHD and was accompanied by up-regulated expression of many chemokines and their receptors (CXCL-1, -2, -9, and -10; CCL-2, -5, -6, -7, -8, -9, -11, and -19; CCR-1 and CCR-5), adhesion molecules (ICAM-1, CD18, Ly69, PSGL-1, VCAM-1), molecules involved in antigen processing and presentation (TAP1 and TAP2, MHC class I and II, CD80), regulators of apoptosis (granzyme B, caspase 7, Bak1, Bax, and BclII), interferon-inducible genes (STAT1, IRF-1, IIGP, GTPI, IGTP, Ifi202A), stimulators of fibroblast proliferation and matrix synthesis (interleukin-1beta, transforming growth factor-beta1), and markers of keratinocyte proliferation (keratins 5 and 6), and differentiation (small proline-rich proteins 2E and 1B). Many acute-phase proteins were up-regulated early in murine cutaneous GVHD including serum amyloid A2 (SAA2), SAA3, serpins a3g and a3n, secretory leukocyte protease inhibitor, and metallothioneins 1 and 2. The kinetics of gene expression were consistent with the evolution of cutaneous pathology as well as with current models of disease progression during cutaneous GVHD.  相似文献   
82.
The image shows a pseudoaneurysm of the mitral-aortic intervalvular fibrosa and a fistula between the non-coronary sinus and the left atrium.  相似文献   
83.

Objective

The purpose of this study was to evaluate the changes in right ventricle (RV) and left ventricle (LV) function after transcatheter atrial septal defect (ASD) closure and to assess the influence of the age and the amount of shunt.

Design

Retrospective study

Patients

Fifty‐three adult patients who underwent transcatheter closure were enrolled, then divided into subgroups according to the age (< 40 years vs ≥ 40 years), and the amount of shunt flow (QpQs < 2.5 vs QpQs ≥ 2.5).

Outcome Measures

Two‐dimensional tissue Doppler imaging was performed in a four‐chamber view at the basal ventricular septum (VS) and tricuspid valve annulus (TVA) before and at 1 month and 6 months after closure. Myocardial velocities, the myocardial performance index (MPI), and isovolumic acceleration (IVA) were assessed.

Results

At the TVA, the MPI decreased slightly and then greatly increased at 6 months after closure (P = .002). The IVA improved in all patients (P < .001), and the E′/A′ ratio decreased, especially in the old age group (P = .031) and larger shunt group (P = .035). At the VS, S′ and the IVA decreased and had not recovered until 6 months in the old age (P = .02) and larger shunt (P = .02). The Qp/Qs showed a significant reverse correlation with a decrease in the E′/A′ at the TVA (r = ?0.37, P = .008), and age of patient was correlated with a decrease in the IVA at the VS (r = ?0.32, P = .019). The age at closure (β = ?0.36, P = .002), the Qp/Qs ratio (β = ?0.45, P = .01), and RV MPI changes (β = ?7.64, P < .001) were found to be associated factors with IVA decrease at the VS.

Conclusions

After ASD closure, RV global function might be impaired. In elderly patients and patients with a large shunt, impairment of LV contractility developed until 6 months after closure. Close long‐term observation is required after closure, especially in old‐age patients with a large shunt.  相似文献   
84.
The cytoskeleton in keratinocytes is a complex of highly homologous structural proteins derived from two families of type I and type II polypeptides. Keratin K2e is a type II polypeptide that is expressed in epidermis late in differentiation. Here we report the influence of keratinocyte activation, proliferation, and keratinization on K2e expression in samples of cutaneous and oral lesions. The normal expression of K2e in the upper spinous and granular layers of interfollicular epidermis is increased in keloid scars but showed distinct down-regulation in psoriasis and hypertrophic scars where keratinocytes are known to undergo activation. Unlike normal and psoriatic skin, K2e expression in hypertrophic and keloid scars began in the deepest suprabasal layer. In cutaneous basal and squamous cell carcinomas, K2e was absent in most tumor islands but the overlying epidermis showed strong expression. No significant K2e expression in nonkeratinized or keratinized oral epithelia, including buccal mucosa, lateral border of tongue and gingiva was detected. In oral lichen planus K2e expression was undetectable, but in benign keratoses of lingual mucosa induction of K2e along with K1 and K10 was observed. In mild-to-moderate oral dysplasia with orthokeratinization, K2e was highly expressed compared with parakeratinized areas but in severe dysplasia as well as in oral squamous cell carcinoma, K2e expression was undetectable. Taken together, the data suggest that K2e expression in skin is sensitive to keratinocyte activation but its up-regulation in oral lesions is a reflection of the degree of orthokeratinization.  相似文献   
85.

Background

Indiscriminate disposal of untreated wastes which are often heavily laden with sewage microorganisms some of which are pathogenic to humans into aquatic environments near cities could serve as potential dangers to human health.

Objective

A prospective study was undertaken to investigate the scope of potential bacterial pathogens and to assess the extent of pollution of the Douala lagoon.

Methods

A total of eighty water samples were collected fortnightly from the lagoon at five stations from March to October 2005 and analysed for heterotrophic bacterial densities, coliform counts, faecal coliform and faecal streptococcal counts. Bacteria were isolated and identified using standard microbiology and biochemical techniques.

Results

High heterotrophic bacterial counts (33 × 105 − 161 × 105 CFU/ mL), total coliform counts (1.8 × 102 − 2.4 × 102 CFU/100 mL), faecal coliform counts (2.2 × 102 − 2.4 × 102 CFU/ 100 mL) and faecal streptococcal counts (2.1 × 102 − 2.3 x 102 CFU/100mL were observed in all sampling stations. Eleven species of bacteria: Bacteroides fragilis, Proteus vulgaris, Klebsiella pneumoniae, E. coli, Enterococcus faecalis, Enterobacter aerogenes, Citrobacter freundii, Aeromonas hydrophila, Pseudomonas aeruginosa, Bacillus mycoides and Serratia marcesens, were frequently isolated.

Conclusion

The presence of potential bacterial agents such as Bacteroides fragilis, Pseudomonas aeruginosa, Aeromonas hydrophila, Klebsiella pneumoniae and E. coli in the lagoon may pose a serious threat to the health and well being of users of the Lagoon and calls for urgent intervention.  相似文献   
86.
87.
88.
Objective. The role of the adaptive immune system has not been explored in detail compared with the innate immune system in systemic JIA (sJIA) pathogenesis. The aim of this study was to examine the phenotype of circulating peripheral blood CD4(+) T-cell subpopulations in a cross-sectional study of sJIA patients during disease remission on medication and during acute flare of the disease. Methods. Flow cytometry was used to examine the phenotype and cytokine production of IFNγ-, IL-4- and IL-17-producing CD4(+) T cells in the peripheral blood of 10 sJIA patients with active disease, 9 sJIA with inactive disease, 14 JIA patients with oligoarticular onset, 10 adult control subjects and 10 age-matched control subjects. In parallel, we examined the proportion of FoxP3(+) Tregs. Results. IFNγ- and IL-17-producing CD4(+) T cells and IL-17-producing CD3(+)CD4(-) T cells were present at higher proportions in the peripheral blood of sJIA patients, irrespective of their disease status. Our data also confirm the known increase of the proportions of IFNγ-producing Th1 cells with increasing age and suggest an increase with age in the IL-17-producing CD4(+) T-cell population. Conclusion. This study is the first to describe significantly higher proportions of Th1 and Th17 T helper cell subsets in the peripheral blood of sJIA patients. These proinflammatory cells may play a pathogenic role in sJIA. Our data also emphasize the importance of using paediatric age-matched control subjects when evaluating the T-cell cytokine profile in JIA.  相似文献   
89.
Recent reports have shown that excellent survival outcomes can be achieved in adult Burkitt’s lymphoma with the use of DA-EPOCH-R regimen. When compared to earlier intense pediatric-type protocols, this regimen is less toxic. There are limited reports available on the use of this regimen outside the context of clinical trials. We analyzed the outcomes of patients who were treated with the DA-EPOCH-R regimen [Burkitt’s lymphoma (BL), primary mediastinal B cell lymphoma (PMBCL) and HIV-positive patients with diffuse large B cell lymphoma (DLBCL)] at our center over a 3 year period. Baseline characters, responses, and toxicity data was captured from records. Event-free survival (EFS—from therapy initiation till occurrence of event (non-achievement of complete response or relapse) and overall survival (OS—from therapy initiation till death due to any cause) were estimated using Kaplan–Meier method. Among 41 patients [median age 40 years (18–76)], the following diagnoses were included-HIV negative patients (N = 29): BL (N = 24), PMBCL (N = 5); HIV positive patients (N = 12): BL (N = 8), and DLBCL (N = 4). Among those with BL, majority had stage III/IV disease (N = 21/32, 65%). At the completion of planned therapy, 33 had achieved CR (81%). One patient died due to toxicity. The actuarial EFS and OS at 2 years were 80 and 77% respectively for all patients. The OS at 2 years was 100% for PMBCL, 80% for BL and 50% for HIV-positive DLBCL. Majority of the failures in BL were in patients with advanced disease. DA-EPOCH-R can be used in real-world setting and allows treatment of older patients with BL.  相似文献   
90.
BackgroundWe investigated whether fibrinogen to albumin ratio (FAR) at diagnosis could reflect the cross‐sectional activity and predict poor outcomes in patients with antineutrophil cytoplasmic antibody (ANCA)‐associated vasculitis (AAV).MethodsThis cross‐sectional study included 54 immunosuppressant drug‐naïve patients with AAV who had the results of plasma fibrinogen and serum albumin at diagnosis. Clinical and laboratory data at diagnosis were collected, and all‐cause mortality, cerebrovascular accident, cardiovascular disease, end‐stage renal disease occurrences were assessed as poor outcomes. FAR was calculated by the following equation: FAR = plasma fibrinogen (g/dl)/serum albumin (g/dl).ResultsThe median age was 65.5 years, and 59.3% of patients were men (33 MPA, 13 GPA and 8 EGPA). FAR was significantly correlated with Birmingham vasculitis activity score (BVAS; r = 0.271), erythrocyte sedimentation rate (ESR; r = 0.668) and C‐reactive protein (CRP; r = 0.638). High BVAS was defined as BVAS ≥16, and the cut‐off of FAR at diagnosis was set as 0.118. AAV patients with FAR at diagnosis ≥0.118 had a significantly higher risk for the cross‐sectional high BVAS than those without (RR 3.361). In the univariable linear regression analysis, CRP (β = 0.383) and FAR (β = 0.297) were significantly correlated with BVAS at diagnosis. However, in the multivariable analysis, none of them was correlated with the cross‐sectional BVAS. FAR at diagnosis could not predict poor outcomes during follow‐up in AAV patients.ConclusionsFibrinogen to albumin ratio at diagnosis could reflect the cross‐sectional BVAS but could not predict poor outcomes in patients with AAV.  相似文献   
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