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101.
102.
All lentiviruses contain an open reading frame located shortly upstream or inside of the env gene and encoding a small protein which has been designated Tat. This designation was mainly with respect to the positional analogy with the first exon of the trans-activator protein of the well studied human immunodeficiency virus type 1 (HIV-1). In this work we comparatively studied the trans- activation activity induced by Tat proteins of the small ruminant Maedi Visna virus (MVV) of sheep and Caprine arthritis encephalitis virus (CAEV) of goats on MVV and CAEV LTRs with that induced by the human lentivirus HIV-1 on its own LTR. The HIV-1 LTR alone weakly expresses the reporter GFP gene except when the HIV-1 Tat protein is coexpressed, the GFP expression is increased 60-fold. In similar conditions only minimal trans-activation increasing two- to three-fold the MVV and CAEV LTR activity was found with MVV Tat protein, and no trans-activation activity was detected in any used cell type or with any virus strain when CAEV Tat was tested. These results indicate that the small ruminant lentiviruses (SRLV) differ from the primate lentiviruses in their control of expression from the viral LTRs and put into question the biological role of the encoded protein named "Tat."  相似文献   
103.
The global burden of disease associated with wounds is an increasingly significant public health concern. Current treatments are often expensive, time‐consuming and limited in their efficacy in chronic wounds. The challenge of overcoming current barriers associated with wound care requires innovative management techniques. Regenerative medicine is an emerging field of research that focuses on the repair, replacement or regeneration of cells, tissues or organs to restore impaired function. This article provides an overview of the pathophysiology of wound healing and reviews the latest evidence on the application of the principal components of regenerative medicine (growth factors, stem cell transplantation, biomaterials and tissue engineering) as therapeutic targets. Improved knowledge and understanding of the pathophysiology of wound healing has pointed to new therapeutic targets. Regenerative medicine has the potential to underpin the design of specific target therapies in acute and chronic wound healing. This personalised approach could eventually reduce the burden of disease associated with wound healing. Further evidence is required in the form of large animal studies and clinical trials to assess long‐term efficacy and safety of these new treatments.  相似文献   
104.
Pharmaceutical Chemistry Journal - Various parts of Crataegus oxyacantha (hawthorn) plant have been used in traditional medicine in many countries including Algeria. In this study, antioxidant...  相似文献   
105.
TP53 abnormalities lead to resistance to purine analogues and are found in over 40% of patients with refractory chronic lymphocytic leukemia (CLL). At diagnosis, no more than 5% of patients carry the 17p deletion, most cases harbour mutations within the other TP53 allele. The incidence of a TP53 mutation as the only alteration is approximately 5%, but this depends on the sensitivity of the technique. Recently, having a complex karyotype has been considered a strong adverse prognostic factor. However, there are no longitudinal studies simultaneously examining the presence of the 17p deletion, TP53 mutations and karyotype abnormalities. We conducted a retrospective longitudinal study of 31 relapsed/refractory CLL patients. Two to six blood samples per patient were analyzed, with a median follow‐up of 8 years. In this report, we assessed the sequence of events of TP53 clonal evolution and correlated the presence of TP53 abnormalities to genetic instability during progression and treatment. Next‐generation sequencing allowed the early detection of TP53 mutated clones and was able to be performed on a routine basis, demonstrating an excellent correlation between the Illumina and Ion Torrent technologies. We concluded that TP53 mutations are early events and precede clonal evolution to complex karyotypes. We strongly recommend the early and iterated detection of TP53 mutations in progressive cases.  相似文献   
106.
From April 2003 to December 2006, 195 patients with de novo symptomatic myeloma and younger than 60 years of age were randomly assigned to receive either tandem transplantation up front (arm A, n = 97) or one autologous stem-cell transplantation followed by a maintenance therapy with thalidomide (day + 90, 100 mg per day during 6 months) (arm B, n = 98). Patients included in arm B received a second transplant at disease progression. In both arms, autologous stem-cell transplantation was preceded by first-line therapy with thalidomide-dexamethasone and subsequent collection of peripheral blood stem cells with high-dose cyclophosphamide (4 g/m(2)) and granulocyte colony stimulating factor. Data were analyzed on an intent-to-treat basis. With a median follow-up of 33 months (range, 6-46 months), the 3-year overall survival was 65% in arm A and 85% in arm B (P = .04). The 3-year progression-free survival was 57% in arm A and 85% in arm B (P = .02). Up-front single autologous transplantation followed by 6 months of maintenance therapy with thalidomide (with second transplant in reserve for relapse or progression) is an effective therapeutic strategy to treat multiple myeloma patients and appears superior to tandem transplant in this setting. This study was registered at www.ClinicalTrials.gov as (NCT 00207805).  相似文献   
107.
108.
Background: Synchronous bilateral breast cancer (SBBC) provides a special condition where two independent breast tumors are exposed to cancer pharmacotherapy within a uniform pharmacokinetic milieu. Both senescence and apoptosis are established responses to therapy; however, they have potentially variable contributions to the overall outcome of treatment, which are yet to be determined. Methods: In this report, we describe the clinicopathological picture of two SBBC cases that received standard anticancer treatment and assess their expression profile of several molecular hallmarks of senescence and apoptosis. Results: Our analysis identified that synchronous tumors have variable expression profiles of both senescence- and apoptosis-associated biomarkers, despite comparable pathological responses to neoadjuvant chemotherapy and current survival rates. Conclusions: Our results highlight the variable expression of senescence- and apoptosis-associated markers in breast tumors (despite the shared somatic genetic background) and invites a large-scale assessment of both senescence and apoptosis in breast cancer tissue in vivo and their contribution to the pathological response and overall survival.  相似文献   
109.

Objective

To investigate the effects of intraarticular glucocorticoid treatment on macrophage infiltration, the expression of the chemokines monocyte chemoattractant protein 1 (MCP‐1) and macrophage inflammatory protein 1α (MIP‐1α), and the expression of matrix metalloproteinases 1 and 3 (MMPs 1 and 3) and their inhibitors, the tissue inhibitors of metalloproteinases 1 and 2 (TIMPs 1 and 2), in osteoarthritis (OA) synovial membranes.

Methods

Forty patients underwent arthroscopic biopsy before and 1 month after intraarticular injection of glucocorticoids. Twenty‐one patients received 120 mg of methylprednisolone acetate (Depo‐Medrol; Upjohn, Kalamazoo, MI), and 20 patients received placebo (1 patient received placebo in 1 knee and methylprednisolone acetate in the other). Immunoperoxidase staining for the expression of CD68, MCP‐1, MIP‐1α, MMP‐1, MMP‐3, TIMP‐1, and TIMP‐2 was performed, and the immunostaining was quantified by color video image analysis.

Results

CD68, MCP‐1, MIP‐1α, MMP‐1, MMP‐3, TIMP‐1, and TIMP‐2 immunostaining was observed in all synovial membranes. Intraarticular glucocorticoid treatment was associated with a small (30%) but statistically significant (P = 0.048) reduction in CD68+ macrophage staining in the synovial lining layer, but there was no change in the CD68 expression in the synovial sublining layer. No significant differences were observed for MCP‐1, MIP‐1α, MMP‐1, MMP‐3, TIMP‐1, and TIMP‐2 immunostaining in the synovial lining or sublining layers.

Conclusion

Intraarticular glucocorticoids may reduce CD68+ macrophage infiltration into the synovial lining layer, but not the expression of MCP‐1, MIP‐1α, MMP‐1, MMP‐3, TIMP‐1, and TIMP‐2 in the synovial membrane, in patients with OA.
  相似文献   
110.

Background:

Bacteremia become fearsome in hematopoietic stem cell transplant (HSCT) recipients with the emergence of multidrug-resistant (MDR) strains.

Aim:

Our purpose was to investigate the prevalence of MDR bacteremia in HSCT recipients at the Tunisian National Bone Marrow Transplant Center, associated factors and attributable mortality rate.

Methods:

Our retrospective study (January 2010-December 2017) included all MDR bacteremia in the Hematology department. MDR rods were: extended spectrum beta-lactamase producing Enterobacterales (ESBL-E), P. aeruginosa and A. baumannii resistant to at least three families of antibiotics, methicillin-resistant S. aureus (MRSA) and vancomycin resistant E. faecium (VRE).

Results:

The prevalence of MDR bacteremia among HSCT recipients was 5.9% (48/816) with a stable trend over time (rs=0.18). Neutropenia, prior hospitalization, prior antibiotherapy and prior colonization with MDR pathogens were observed in 59%, 58%, 48% and 31% of cases, respectively. Imipenem was the most prescribed first-line antibiotic (50%). The attributable mortality rate was 13%. MDR bacteria (n=48) belonged to ESBL-E (60%), P. aeruginosa (19%), A. baumannii (13%), MRSA (4%) and VRE (4%). For ESBL-E and P. aeruginosa, the rates of antibiotic resistance were respectively, 17% and 44% to imipenem, 31% and 56% to amikacin and 15% and 0% to colistin. Strains of A. baumannii were susceptible only to colistin. The MRSA (n=2) were resistant to ciprofloxacin and gentamicin and susceptible to glycopeptides. The VRE (n=2) were susceptible to linezolid and tigecycline.

Conclusion:

Low prevalence of MDR bacteremia in HSCT recipients but high attributable mortality rate, requiring reinforcement of hygiene measures.  相似文献   
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