High-Throughput Generation of P. falciparum Functional Molecules by Recombinational Cloning

Large-scale functional genomics studies for malaria vaccine and drug development will depend on the generation of molecular tools to study protein expression. We examined the feasibility of a high-throughput cloning approach using the Gateway system to create a large set of expression clones encoding Plasmodium falciparum single-exon genes. Master clones and their ORFs were transferred en masse to multiple expression vectors. Target genes (n = 303) were selected using specific sets of criteria, including stage expression and secondary structure. Upon screening four colonies per capture reaction, we achieved 84% cloning efficiency. The genes were subcloned in parallel into three expression vectors: a DNA vaccine vector and two protein expression vectors. These transfers yielded a 100% success rate without any observed recombination based on single colony screening. The functional expression of 95 genes was evaluated in mice with DNA vaccine constructs to generate antibody against various stages of the parasite. From these, 19 induced antibody titers against the erythrocytic stages and three against sporozoite stages. We have overcome the potential limitation of producing large P. falciparum clone sets in multiple expression vectors. This approach represents a powerful technique for the production of molecular reagents for genome-wide functional analysis of the P. falciparum genome and will provide for a resource for the malaria resource community distributed through public repositories.     

Hepatitis C virus-specific T-cell reactivity during interferon and ribavirin treatment in chronic hepatitis C

BACKGROUND & AIMS: The role of virus-specific T-helper lymphocyte reactivity in determining the therapeutic response in chronic hepatitis C virus (HCV) infection is not fully understood. METHODS: We studied CD4(+) T lymphocyte proliferation together with interferon (IFN)-gamma and interleukin (IL)-10 production from peripheral blood mononuclear cells in response to 4 HCV antigens (core, NS3, NS4, and NS5) in 25 patients with chronic hepatitis C undergoing antiviral therapy with IFN alone or in combination with ribavirin, prospectively, before, during, and after treatment. RESULTS: HCV-specific T-cell reactivity was uncommon at baseline but increased markedly during antiviral therapy, peaking around treatment weeks 4-8. Resolution of hepatitis C viremia was significantly more likely in patients who developed HCV-specific T-cell proliferation with increased IFN-gamma production. The main difference in T-cell reactivity of patients treated with IFN plus ribavirin was a significantly lower production of IL-10, whereas lymphocyte proliferation was similar to that in patients receiving IFN monotherapy. CONCLUSIONS: Treatment-induced control of hepatitis C viremia is associated with the development of HCV-specific T-cell responses with enhanced IFN-gamma and low IL-10 production. The greater efficacy of combination therapy with IFN-alpha plus ribavirin may be related to its ability to suppress HCV-specific IL-10 production.     

Negative effect of lockdown on juvenile idiopathic arthritis patients

Clinical Rheumatology - The aim of this study is to evaluate a possible negative action of lockdown, during the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, in the...     

Covered metal stents for management of inoperable malignant colorectal strictures

BACKGROUND: Metal stents have been reported as an effective alternative to surgery for the palliation of patients with colorectal neoplastic obstruction. Because most of the published series describe the use of uncovered stents, the purpose of our study was to prospectively evaluate the effectiveness, feasibility, safety, and outcome of covered stents for the palliative treatment of malignant colorectal strictures. METHODS: Sixteen patients with advanced distal colorectal cancer underwent placement of 10 and 12 cm long, 23 mm diameter covered stents under fluoroscopic and endoscopic control. Clinical and endoscopic follow-up was scheduled at 3- to 6-week intervals. RESULTS: Stent insertion was successful in 15 of 16 patients (93%). Perforation occurred in one patient during stent placement requiring colostomy. Relief of bowel obstruction was documented in all successfully treated patients. The median follow-up was 21 weeks (range 1 to 46). No recurrence of obstruction was observed during the follow-up period. Stent migration occurred in 2 patients, 7 and 21 days after stent placement. CONCLUSIONS: Covered stents may provide safe and effective palliation of patients with malignant rectosigmoid strictures. Prolonged luminal patency and sealing of fistulous tracts are potential advantages of covered versus uncovered stents in the palliative treatment of colorectal malignancies. ?     

Evaluation of patients with jejunostomy tubes: imaging findings

PURPOSE: To determine the frequency and nature of abnormalities observed on radiographs after placement of jejunostomy (J) tubes for enteral nutrition. MATERIALS AND METHODS: Radiology database review revealed that 280 studies of the J tube or of the small bowel with water-soluble contrast material and/or barium sulfate were performed in patients during 10 years. Review of the radiologic reports revealed abnormalities related to the placement of tubes in 105 (38%) cases. Images were reviewed to determine abnormalities in these 105 cases. Radiologic, medical, and surgical records were also reviewed to determine the clinical course and any subsequent interventions. RESULTS: One or more complications were detected in 40 (14%) of 280 cases: small-bowel obstruction in 17 (6%) cases, nonobstructive small-bowel narrowing in six (2%), extraluminal tracks or collections in seven (2%), extravasation of contrast material to the skin in 11 (4%), jejunal hematomas in five (2%), and intussusceptions in four (1%). Mechanical problems related to the tube were detected in 52 (19%) cases, including coiling, kinking, or knotting of the tube in 38 (14%), malpositioning in five (2%), retrograde flow in four (1%), occlusion in four (1%), and a hole in one (<1%). Focal thickening of small-bowel folds was detected in 24 (9%) cases. CONCLUSION: Radiographs in 280 patients with J tubes revealed one or more complications that resulted from tube placement (40 [14%] cases), mechanical problems related to location or function of the tube (52 [19%] cases), and development of focally thickened small-bowel folds (24 [9%] cases).     

Ectopic liver and hepatocarcinogenesis: report of three cases with four years' follow-up

Hepatocellular carcinoma (HCC) may arise in ectopic livers, which are autonomous islands of normal liver parenchyma located in the abdomen or thorax. The majority of HCCs in ectopic livers are reported in oriental patients. We describe here three new cases of HCC in Caucasian patients. The clinical presentation varied from dull epigastric pain in one patient, to abrupt onset with signs and symptoms of acute abdomen caused by intra-abdominal bleeding in another patient, to an unexplained progressive increase of alpha-fetoprotein serum levels in a third patient. None had risk factors for HCC or liver disease. One of the patients developed HCC at age 34 years; she is the youngest patient ever described to develop HCC in ectopic liver. Our data further strengthen the hypothesis that ectopic livers are particularly predisposed to developing HCC. The patients were followed up for 4 years after surgery: two remain free of disease, suggesting that the unique localisation and growth pattern may render these tumours particularly susceptible to curative resection.