Modulation of immune responses following solid organ transplantation by microRNA

Organ transplantation, an accepted treatment for end stage organ failure, is often complicated by allograft rejection and disease recurrence. In this review we will discuss the potential role of microRNAs in allograft immunity especially leading to rejection of the transplanted organ. microRNAs (miRNAs), originally identified in C. elegans, are short non-coding 21–24 nucleotide sequences that bind to its complementary sequences in functional messenger RNAs and inhibits post-translational processes through RNA duplex formation resulting in gene silencing (Lau et al., 2001). Gene specific translational silencing by miRNAs regulates pathways for immune responses such as development of innate immunity, inflammation, T-cell and B-cell differentiation and signaling that are implicated in various stages of allograft rejection. miRNAs also play a role in development of post-transplant complicacies like fibrosis, cirrhosis, carcinogenesis often leading to graft loss and poor patient outcome. Recent advancements in the methods for detecting and quantifying miRNA in tissue biopsies, as well as in serum and urine samples, has led to identification of specific miRNA signatures in patients with allograft rejection and have been utilized to predict allograft status and survival. Therefore, miRNAs play a significant role in post-transplant events including allograft rejection, disease recurrence and tumor development impacting patient outcome.     

Indurated vascular plaques on the legs of an 85-year-old woman

This is a case of classic type Kaposi sarcoma occurring in an 85-year-old woman who presented with indurated vascular plaques on both legs below the knee that has been present for two years. A brief review of the literature on Kaposi sarcoma is included.     

A simple method for amplifying RNA targets (SMART)

We present a novel and simple method for amplifying RNA targets (named by its acronym, SMART), and for detection, using engineered amplification probes that overcome existing limitations of current RNA-based technologies. This system amplifies and detects optimal engineered ssDNA probes that hybridize to target RNA. The amplifiable probe-target RNA complex is captured on magnetic beads using a sequence-specific capture probe and is separated from unbound probe using a novel microfluidic technique. Hybridization sequences are not constrained as they are in conventional target-amplification reactions such as nucleic acid sequence amplification (NASBA). Our engineered ssDNA probe was amplified both off-chip and in a microchip reservoir at the end of the separation microchannel using isothermal NASBA. Optimal solution conditions for ssDNA amplification were investigated. Although KCl and MgCl(2) are typically found in NASBA reactions, replacing 70 mmol/L of the 82 mmol/L total chloride ions with acetate resulted in optimal reaction conditions, particularly for low but clinically relevant probe concentrations (≤100 fmol/L). With the optimal probe design and solution conditions, we also successfully removed the initial heating step of NASBA, thus achieving a true isothermal reaction. The SMART assay using a synthetic model influenza DNA target sequence served as a fundamental demonstration of the efficacy of the capture and microfluidic separation system, thus bridging our system to a clinically relevant detection problem.     

Bioevaluation of radioactive bandages in a murine model of melanoma

Purpose: To study the effectiveness of a radioactive bandage incorporating a β^? emitter for the treatment of superficial tumours like melanoma.

Materials and methods: ¹⁸⁸Re tin particles were immobilized on a bandage patch (¹⁸⁸Re bandage). The effectiveness of the ¹⁸⁸Re bandage for controlling tumour growth was tested in C57BL/6 mice bearing BL6/FIO melanoma. The effect of the single dose delivered, two‐dose treatment and time of contact of bandages on the skin was studied by following tumour size.

Results: Tumour growth was delayed significantly in treated animals compared with controls. Complete tumour regression was observed with some doses of radiation. Histology studies and dose‐rate calculations were also carried out to evaluate the effectiveness of ¹⁸⁸Re bandages.

Conclusions: Radioactive bandages could be a promising modality for the treatment of skin cancers.     

Fibroma of tendon sheath

This report describes a 60-year-old woman with a fibroma of tendon sheath of left hand. Ultrastructural study of the tumor reveals the nature of the tumor cells as fibroblasts, thus distinguishing it from the more common giant cell tumor of tendon sheath believed to be derived from synovial cells.     

Spindle cell mucoepidermoid carcinoma of submandibular gland

A malignant tumor of the submandibular gland was found to consist predominately of spindle cell elements that initially suggested a primary sarcoma. Further examination revealed that the spindled malignant cells were derived from a high-grade mucoepidermoid carcinoma.     

用电化学检测器的高效液相色谱法测定血清及尿中速尿的含量

本文报告了用电化学检测器的高效液相色谱法测定血清及尿中速尿含量的方法。样品予处理方法:血清用乙腈除蛋白,尿用蒸馏水稀释50倍。采用作者合成的FD-Val-OH作为内标物。色谱条件为:反相柱,以含35%乙醇的5mmol/L四丁基铵水溶液为流动相(pH7.50),流速1.0ml/min;用电化学检测器,检测电压0.90V:速尿及内标物的保留时间分别为10和15min。通过计算速尿对内标物的峰高比求得速尿含量。血清及尿中的最低检测浓度分别为16和9ng/ml。标准曲线在0.25～5ng/μl(血清)、0.5～10ng/μl(尿)的浓度范围内呈线性关系。血清及尿中回收率分别为100.5%和100.6%。变异系数在4.6%以下。