Application of Multiplex PCR for Detection and Differentiation of Entamoeba histolytica,Entamoeba dispar and Entamoeba moshkovskii

Background

Entamoeba moshkovskii and E. dispar are impossible to differentiate microscopically from the pathogenic species E. histolytica. Multiplex polymerase chain reaction (Multiplex PCR) is a widespread molecular biology technique for amplification of multiple targets in a single PCR experiment.

Methods

For detection and differentiation of the three-microscopy indistinguishable Entamoeba species in human, multiplex PCR assay using different DNA extraction methods was studied. A conserved forward primer was derived from the middle of the small-subunit rRNA gene, and reverse primers were designed from signature sequences specific to each of these three Entamoeba species.

Results

A 166-bp PCR product with E. histolytica DNA, a 580-bp product with E. moshkovskii DNA and a 752-bp product with E. dispar DNA were generated in a single-round and multiplex PCR reaction.

Conclusion

We recommend this PCR assay as an accurate, rapid, and effective diagnostic method for the detection and discrimination of these three Entamoeba species in both routine diagnosis of amoebiasis and epidemiological surveys.     

The HMG-CoA reductase inhibitor simvastatin overcomes cell adhesion-mediated drug resistance in multiple myeloma by geranylgeranylation of Rho protein and activation of Rho kinase

Primary drug resistance is a major problem in multiple myeloma, an incurable disease of the bone marrow. Cell adhesion-mediated drug resistance (CAM-DR) causes strong primary resistance. By coculturing multiple myeloma cells with bone marrow stromal cells (BMSCs), we observed a CAM-DR of about 50% to melphalan, treosulfan, doxorubicin, dexamethasone, and bortezomib, which was not reversed by secreted soluble factors. Targeting the adhesion molecules lymphocyte function-associated antigen 1 (LFA-1) and very late antigen 4 (VLA-4) by monoclonal antibodies or by the LFA-1 inhibitor LFA703 reduced CAM-DR significantly. Only statins such as simvastatin and lovastatin, however, were able to completely restore chemosensitivity. All these effects were not mediated by deadhesion or reduced secretion of interleukin 6. Targeting geranylgeranyl transferase (GGTase) and Rho kinase by specific inhibitors (GGTI-298 and Y-27632), but not inhibition of farnesyl transferase (FTase) by FTI-277, showed similar reduction of CAM-DR. Addition of geranylgeranyl pyrophosphate (GG-PP), but not of farnesyl pyrophosphate (F-PP), was able to inhibit simvastatin-induced CAM-DR reversal. Our data suggest that the 3-hydroxy-3-methylglutaryl-coenzyme-A (HMG-CoA)/GG-PP/Rho/Rho-kinase pathway mediates CAM-DR and that targeting this pathway may improve the efficacy of antimyeloma therapies by reduction of CAM-DR.     

Tissue-engineered cartilage with inducible and tunable immunomodulatory properties

The pathogenesis of osteoarthritis is mediated in part by inflammatory cytokines including interleukin-1 (IL-1), which promote degradation of articular cartilage and prevent human mesenchymal stem cell (MSC) chondrogenesis. In this study, we combined gene therapy and functional tissue engineering to develop engineered cartilage with immunomodulatory properties that allow chondrogenesis in the presence of pathologic levels of IL-1 by inducing overexpression of IL-1 receptor antagonist (IL-1Ra) in MSCs via scaffold-mediated lentiviral gene delivery. A doxycycline-inducible vector was used to transduce MSCs in monolayer or within 3D woven PCL scaffolds to enable tunable IL-1Ra production. In the presence of IL-1, IL-1Ra-expressing engineered cartilage produced cartilage-specific extracellular matrix, while resisting IL-1-induced upregulation of matrix metalloproteinases and maintaining mechanical properties similar to native articular cartilage. The ability of functional engineered cartilage to deliver tunable anti-inflammatory cytokines to the joint may enhance the long-term success of therapies for cartilage injuries or osteoarthritis.     

Artemether: a new therapeutic strategy in experimental rheumatoid arthritis

The current research was designed to determine the effect of artemether in treatment of experimental rheumatoid arthritis. Collagen-induced arthritis was induced in Lewis rats. The intramusculary administration of artemether (ART) and intraperitoneally injection of methotrexate (MTX) were started on day 25 postimmunization and continued until final assessment on day 35. During this period, clinical examination was taken intermittently. The anticollagen type II antibody (CII Ab) and nitric oxide synthesis were measured. The paws and kness were then removed for histopathology and radiography assay.The biocompatibility of ART and MTX were assessed using fibrosarcoma cell line. Data showed that i.m. injection of ART to arthritic rats induced a significant reduction in paw edema. This beneficial effect was associated with a significant decrease in anti-CII antibody response compared with untreated rats. Histopathological assessment showed a reduced inflammatory cell infiltrate in joints of treated rats; tissue edema, and bone erosion in the paws were markedly reduced following ART therapy. Furthermore, our radiography results paralleled our histological findings. Cytotoxicity analysis of ART showed greater tolerability compared with MTX. Treatment with ART significantly diminished NO formation in treated rats compared with nontreated controls. Our data shed light on the therapeutic efficacy of artemether in experimental rheumatoid arthritis compared with a choice drug (methotrexate), and it may be offered as a second-line drug in treatment of rheumatoid arthritis.     

New onset hypertension after transplantation

It has been reported that up to 90% of organ transplant recipients have suboptimal blood pressure control. Uncontrolled hypertension is a well-known culprit of cardiovascular and overall morbidity and mortality. In addition, rigorous control of hypertension after organ transplantation is a crucial factor in prolonging graft survival. Nevertheless, hypertension after organ transplantation encompasses a broader range of causes than those identified in non-organ transplant patients. Hence, specific management awareness of those factors is mandated. An in-depth understanding of hypertension after organ transplantation remains a debatable issue that necessitates further clarification. This article provides a comprehensive review of the prevalence, risk factors, etiology, complications, prevention, and management of hypertension after organ transplantation.     

A molecularly integrated grade for meningioma

BackgroundMeningiomas are the most common primary intracranial tumor in adults. Clinical care is currently guided by the World Health Organization (WHO) grade assigned to meningiomas, a 3-tiered grading system based on histopathology features, as well as extent of surgical resection. Clinical behavior, however, often fails to conform to the WHO grade. Additional prognostic information is needed to optimize patient management.MethodsWe evaluated whether chromosomal copy-number data improved prediction of time-to-recurrence for patients with meningioma who were treated with surgery, relative to the WHO schema. The models were developed using Cox proportional hazards, random survival forest, and gradient boosting in a discovery cohort of 527 meningioma patients and validated in 2 independent cohorts of 172 meningioma patients characterized by orthogonal genomic platforms.ResultsWe developed a 3-tiered grading scheme (Integrated Grades 1-3), which incorporated mitotic count and loss of chromosome 1p, 3p, 4, 6, 10, 14q, 18, 19, or CDKN2A. 32% of meningiomas reclassified to either a lower-risk or higher-risk Integrated Grade compared to their assigned WHO grade. The Integrated Grade more accurately identified meningioma patients at risk for recurrence, relative to the WHO grade, as determined by time-dependent area under the curve, average precision, and the Brier score.ConclusionWe propose a molecularly integrated grading scheme for meningiomas that significantly improves upon the current WHO grading system in prediction of progression-free survival. This framework can be broadly adopted by clinicians with relative ease using widely available genomic technologies and presents an advance in the care of meningioma patients.     

Leiomyosarcoma of somatic soft tissues: a tumor of vascular origin with multivariate analysis of outcome in 42 cases.

Leiomyosarcomas of the somatic soft tissues (SST) are rare compared with their retroperitoneal and cutaneous counterparts and, therefore, have not been extensively studied. We have analyzed the clinicopathologic features of 42 SST leiomyosarcomas referred in consultation to determine what factors affect outcome. Cutaneous, visceral, retroperitoneal, uterine, gastrointestinal, and major vessel leiomyosarcomas were excluded. By definition all lesions possessed at least focal cytologic atypia and mitotic activity, although the latter varied from <1/10 high power fields to 66/10 high power fields. The patients (21 females and 21 males) ranged in age from 26 to 86 years (mean 60 years); tumors developed in the lower (n = 28) or upper extremity (n = 11) and trunk (n = 3). Most arose in deep (n = 27) as opposed to superficial (n = 15) soft tissue; 39 arose from a small vein. During the follow-up period (mean 47 months, range 9-162 months), 3 of 38 (8%) patients developed local recurrence and 17 of 38 metastasized (45%) mostly to the lungs. In a univariate analysis age >62 years, size >4 cm, extensive necrosis, modified updated French Federation of Cancer Centers (FFCC) grade, and whether the tumor had been "disrupted" by a previous incisional biopsy or incomplete excision were significantly correlated with metastasis. AJCC stage also approached significance (p = 0.096) but could not be reliably tested because of the sparseness of the data. In multivariate analyses the logistic regression model that best predicted metastasis at 36 months incorporated the effects of age, FFCC grade, and disruption and had a sensitivity of 94.1% and a specificity of 95.2%. Disruption was the only significant risk factor for metastasis in a multivariate analysis (relative risk 2.70; p = 0.0001) but was strongly correlated with large size and deep location. Other parameters did not improve the predictive power of the model significantly. We concluded that the majority of SST leiomyosarcomas are actually of vascular origin, an observation that has clinical and possibly biologic ramifications. Our histologic definition of leiomyosarcoma to include atypia and any level of mitotic activity appears warranted by the biologic outcome in our cases. The risk of metastasis can be calculated from a model incorporating age, FFCC grade, and disruption. Because disruption correlates with size and depth, it could represent a surrogate as opposed to causal marker for metastasis. Nevertheless, in view of their vascular origin, the possibility that tumor disruption may facilitate or promote access to the bloodstream merits further study.     

The role of biomechanics and inflammation in cartilage injury and repair

Osteoarthritis is a painful and debilitating disease characterized by progressive degenerative changes in the articular cartilage and other joint tissues. Biomechanical factors play a critical role in the initiation and progression of this disease, as evidenced by clinical and animal studies of alterations in the mechanical environment of the joint caused by trauma, joint instability, disuse, or obesity. The onset of these changes after joint injury generally has been termed posttraumatic arthritis and can be accelerated by factors such as a displaced articular fracture. Within this context, there is considerable evidence that interactions between biomechanical factors and proinflammatory mediators are involved in the progression of cartilage degeneration in posttraumatic arthritis. In vivo studies have shown increased concentrations of inflammatory cytokines and mediators in the joint in mechanically induced models of osteoarthritis. In vitro explant studies confirm that mechanical load is a potent regulator of matrix metabolism, cell viability, and the production of proinflammatory mediators such as nitric oxide and prostaglandin E2. Knowledge of the interaction of inflammatory and biomechanical factors in regulating cartilage metabolism would be beneficial to an understanding of the etiopathogenesis of posttraumatic osteoarthritis and in the improvement of therapies for joint injury.