<Emphasis Type="Italic">In Vivo</Emphasis> Detection of miRNA Expression in Tumors Using an Activatable Nanosensor

Purpose

The development of tools for the analysis of microRNA (miRNA) function in tumors can advance our diagnostic and prognostic capabilities. Here, we describe the development of technology for the profiling of miRNA expression in the tumors of live animals.

Procedures

The approach is based on miRNA nanosensors consisting of sensor oligonucleotides conjugated to magnetic nanoparticles for systemic delivery. Feasibility was demonstrated for the detection of miR-10b, implicated in epithelial to mesenchymal transition and the development of metastasis. The miR-10b nanosensor was tested in vivo in two mouse models of cancer. In the first model, mice were implanted subcutaneously with MDA-MB-231-luc-D3H2LN tumors, in which miR-10b was inhibited. In the second model, mice were implanted bilaterally with metastatic MDA-MB-231 and nonmetastatic MCF-7 cells. The nanosensors were injected intravenously, and fluorescence intensity in the tumors was monitored over time.

Results

We showed that the described nanosensors are capable of discriminating between tumors based on their expression of miR-10b. Radiant efficiency was higher in the miR-10b-active tumors than in the miR-10b-inhibited tumors and in the MDA-MB-231 tumors relative to the MCF-7 tumors.

Conclusions

The described technology provides an important tool that could be used to answer questions about microRNA function in cancer.

     

An Evaluation of Coverage and Compliance of Mass Drug Administration 2006 for Elimination of Lymphatic Filariasis in Endemic Areas of Gujarat

Background:

Mass drug administration (MDA) means once-in-a-year administration of diethyl carbamazine (DEC) tablet to all people (excluding children under 2 years, pregnant women and severely ill persons) in identified endemic areas. It aims at cessation of transmission of lymphatic filariasis.

Objective:

What has been the coverage and compliance of MDA in Gujarat during the campaign in December 2006?

Study Design:

Cross-sectional population based house-to-house visit.

Setting:

Urban and rural areas in Gujarat identified as endemic for filariasis where MDA 2006 was undertaken.

Study Variables:

Exploratory - Rural and urban districts; Outcome - coverage, compliance, actual coverage, side effects.

Analysis:

Percentage and proportions.

Results:

Twenty-six clusters, each comprising 32 households from six endemic districts, yielded an eligible population of 4164. The coverage rate was 85.2% with variation across different areas. The compliance with drug ingestion was 89% with a gap of 11% to be targeted by intensive IEC. The effective coverage (75.8%) was much below the target (85%). Side effects of DEC were minimum, transient and drug-specific. Overall coverage was marginally better in rural areas. The causes of poor coverage and compliance have been discussed and relevant suggestions have been made.     

Angiomatoid malignant fibrous histiocytoma

Angiomatoid malignant fibrous histiocytoma (MFH), is a rare but distinct fibrohistiocytic tumour of children and young adults, simulating a vascular neoplasm. A case of angiomatoid malignant fibrous histiocytoma in a 12 year old male is reported.     

Long Term Outcome and Prognostic Factors for Large Hepatocellular Carcinoma (10 cm or more) after Surgical Resection

Background Surgical resection is the standard treatment for hepatocellular carcinoma (HCC). However, the role of surgery in treatment of large tumors (10 cm or more) is controversial. We have analyzed, in a single centre, the long-term outcome associated with surgical resection in patients with such large tumors. Methods We retrospectively investigated 166 patients who had undergone surgical resection between July 1995 and December 2006 because of large (10 cm or more) HCC. Survival analysis was done using the Kaplan-Meier method. Prognostic factors were evaluated using univariate and multivariate analyses. Results Of the 166 patients evaluated, 80% were associated with viral hepatitis and 48.2% had cirrhosis. The majority of patients underwent a major hepatectomy (48.2% had four or more segments resected and 9% had additional organ resection). The postoperative mortality was 3%. The median survival in our study was 20 months, with an actuarial 5-year and 10-year overall survival of 28.6% and 25.6%, respectively. Of these patients, 60% had additional treatment in the form of transarterial chemoembolization, radiofrequency ablation or both. On multivariate analysis, vascular invasion (P < 0.001), cirrhosis (P = 0.028), and satellite lesions/multicentricity (P = 0.006) were significant prognostic factors influencing survival. The patients who had none of these three risk factors had 5-year and 10-year overall survivals of 57.7% each, compared with 22.5% and 19.3%, respectively, for those with at least one risk factor (P < 0.001). Conclusions Surgical resection for those with large HCC can be safely performed with a reasonable long-term survival. For tumors with poor prognostic factors, there is a pressing need for effective adjuvant therapy.     

Immunolocalization of secretory proteins of Aspergillus fumigatus using monospecific polyclonal antibodies in a murine model

The incidence of life-threatening mycoses caused by opportunistic fungi has increased dramatically in recent years with members of the genera Candida and Aspergillus being the most commonly encountered species. Prompt initiation of antifungal therapy for good prognosis of such cases is highly dependent on accurate diagnosis. The potential of metabolic antigens in the diagnosis of aspergillosis was investigated in the present study. Two proteins of 18 and 70 kDa were identified with success rate of 35% and 60% respectively based on their reactivity with patient sera of clinically diagnosed cases of aspergillosis. The antibodies raised against 70 and 18 kDa proteins in rabbits were found to be useful in detection of A. fumigatus in the kidneys of a mouse model of aspergillosis.     

Monoclonal immunoglobulin G1 directed against Aspergillus fumigatus cell wall glycoprotein protects against experimental murine aspergillosis

Most of the biological functions related to pathogenicity and virulence reside in the fungal cell wall, which, being the outermost part of the cell, mediates the host-fungus interplay. For these reasons much effort has focused on the discovery of useful inhibitors of cell wall glucan, chitin, and mannoprotein biosynthesis. In the absence of a wide-spectrum, safe, and potent antifungal agent, a new strategy for antifungal therapy is directed towards the development of monoclonal antibodies (MAbs). In the present study the MAb A9 (immunoglobulin G1 [IgG1]) was identified from hybridomas raised in BALB/c mice immunized with cell wall antigen of Aspergillus fumigatus. The immunoreactive epitopes for this IgG1 MAb appeared to be associated with a peptide moiety, and indirect immunofluorescence microscopy revealed its binding to the cell wall surface of hyphae as well as with swollen conidia. MAb A9 inhibited hyphal development as observed by MTT [3-(4,5-dimethythiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay (25.76%), reduced the duration of spore germination, and exerted an in vitro cidal effect against Aspergillus fumigatus. The in vivo protective efficacy of MAb A9 was also evaluated in a murine model of invasive aspergillosis, where a reduction in CFU (>4 log(10) units) was observed in kidney tissue of BALB/c mice challenged with A. fumigatus (2 x 10(5) CFU/ml) and where enhanced mean survival times (19.5 days) compared to the control (7.1 days) and an irrelevant MAb (6.1 days) were also observed.