槲寄生化学成分的研究——Ⅵ.槲寄生新甙Ⅵ中手性碳的绝对构型测定

本文采用降解及与已知构型的化合物进行对比的方法,确定了新黄酮甙槲寄生新甙Ⅳ中酸性部分手性碳的绝对构型     

New hepatitis B virus mutant form in a blood donor that is undetectable in several hepatitis B surface antigen screening assays

BACKGROUND: Envelope mutant forms of hepatitis B virus (HBV), impairing HBV antibody recognition, have been reported with mutations in single or multiple sites of the hepatitis B surface antigen (HBsAg) group- specific "a" determinant. Blood donors infected with such an HBsAg mutant form of HBV may escape detection by HBsAg screening assays and therefore may affect the safety of the blood supply. CASE REPORT: A repeat blood donor became HBsAg-reactive in an enzyme immunoassay. Confirmatory testing yielded negative results for HBsAg in a radioimmunoassay and in four enzyme immunoassays used in blood donor screening. The specificity of the HBsAg reactivity in the first enzyme immunoassay was confirmed by HBsAg neutralization with antibody to HBsAg. Additional HBV confirmatory test results were positive for antibody to hepatitis B core antigen and antibody to hepatitis B e antigen; negative for antibody to HBsAg and for hepatitis B e antigen; and positive for HBV DNA. DNA sequence analysis of the "a" determinant region of HBsAg revealed amino acid substitutions from Q (Gln) to R (Arg) at codon 129 and from M (Met) to T (Thr) at codon 133. CONCLUSION: This case illustrates the presence of HBsAg mutant forms of HBV in a West European blood donor population that were undetected by several HBsAg screening assays. Adaptation of HBsAg screening is indicated to overcome deficiencies in sensitivity in detecting HBsAg mutant forms of HBV. Screening for antibody to hepatitis B core antigen or HBV DNA may also detect blood donors infected with HBsAg mutant forms of HBV     

Angular deformity of the lower extremity: evaluation with quantitative bone scintigraphy. Work in progress

A technique for quantitative analysis of growth plates in varus or valgus deformity about the knee has been developed. Computer-generated regions of interest are placed on magnification scintigraphs to divide distal femoral and proximal tibial physes into four equal segments. The ratio of counts in the medial half to counts in the lateral half was studied in 34 children (23 healthy, 11 with angular deformity). Normal ratios were 0.74-0.98 for femurs and 0.98-1.20 for tibias. An above-normal ratio correlated with the presence of valgus deformity and a below-normal ratio with varus deformity. This technique may provide a means of monitoring growth after trauma or infection.     

槲寄生化学成分的研究——Ⅵ.槲寄生新甙Ⅵ中手性碳的绝对构型测定

本文采用降解及与已知构型的化合物进行对比的方法,确定了新黄酮甙槲寄生新甙Ⅳ中酸性部分手性碳的绝对构型。     

Neurofibromas: location by scanning with Tc-99m DTPA. Work in progress

The accumulation of technetium-99m diethylenetriamine pentaacetic acid (Tc-99m DTPA) in benign soft-tissue neurofibromatosis tumors is reported. In a series of 16 patients with clinical stigmata of neurofibromatosis, 28 sites of abnormal soft-tissue localization of the isotope observed scintigraphically were documented to be sites of soft-tissue tumor by clinical and/or radiographic (predominantly computed tomographic) correlations. The smallest lesion detected was a 1.5-cm subcutaneous neurofibroma. Normal physiologic nonrenal distribution of the Tc-99m DTPA was established by scintigraphic imaging of a control population.     

Central nervous system lesions in pediatric patients: Gd-DTPA-enhanced MR imaging

Twenty pediatric patients, aged 2-18 years, with known or suspected masses in the brain and/or spinal cord were studied with magnetic resonance imaging at 0.6T with and without use of 0.1 mmol/kg gadolinium diethylenetriaminepentaacetic acid (Gd-DTPA). The multisection, multiecho imaging mode was utilized. Surgically proved mass lesions included astrocytoma (n = 6), medulloblastoma (n = 2), ependymoma (n = 1), craniopharyngioma (n = 1), oligodendroglioma (n = 1), germinoma (n = 1) and fibrosarcoma (n = 1). Presumptive diagnoses included astrocytoma (n = 3), arachnoid cyst (n = 1), tuberous sclerosis (n = 1), cryptic vascular malformation (n = 1), and normal (n = 1). There was dramatic enhancement in 11 of 20 patients, with improved definition of the presence and extent of lesions in six patients. No adverse effects were noted in any of the 20 patients. It is concluded that Gd-DTPA is useful in delineating the presence, extent, and number of certain lesions of the central nervous system in children.     

Rapid Preparation of High-Quality Frozen Sections Using a Membrane and Vacuum System Embedding Machine

BACKGROUND A wide variety of embedding techniques have been employed to process frozen sections for Mohs micrographic surgery. Prospective data comparing different techniques are lacking.
OBJECTIVE The purpose of this study was to compare tissue processing times and slide quality using the three embedding techniques.
METHODS Seventy-five consecutive Mohs surgery tissue specimens, measuring 1 cm in diameter, were prospectively randomized to processing with the CryoHist, the Cryocup, or the Miami Special. Tissue preparation times were recorded, and slide quality was evaluated. Tissue specimen preparation was standardized to exclude the use of relaxing incisions or other tissue manipulations. In a separate evaluation, slide quality was retrospectively evaluated for 50 large specimens (>2.5 cm) processed with the CryoHist machine.
RESULTS The mean tissue processing time was 11.4 minutes using the CryoHist, 12.9 minutes using the Cryocup, and 12.6 minutes using the Miami Special. Slide quality, using epidermal edge as a primary end point, was superior with the CryoHist compared to the other methods. For large (>2.5 cm) en bloc Mohs specimens processed using the CryoHist, the slide quality was excellent with 92.3% of epidermal edge obtained.
CONCLUSIONS The fully automated CryoHist embedding machine enables high-quality frozen sections to be processed in less time than the Cryocup or the Miami Special. Slide quality is excellent, even for larger specimens.     

灰毡毛忍冬化学成分研究V灰毡毛忍冬素F和G的结构测定

Lonicera macranthoides Hand. -Mazz of Caprifoliaceae is the sources of Jinyinhua, which is a well known antipyretic and antidote in traditional Chinese medicine. Chemical studies led us to isolate 11 new compounds.Further purification of a bioactive fraction from the EtOAc soluble portion yielded two new compounds named macranthoin F and G,Their structures wereelucidated as methyl 3,4-O-dicaffeoylquinate(Ⅰ)and methyl 3,5-O-dicaffeoylquinate(Ⅱ).