High prevalence and seasonality of cryptosporidiosis in a small rural village occupied predominantly by aged people in the Republic of Korea.

The prevalence of Cryptosporidium parvum infection and its seasonality were studied in a small rural village occupied predominantly by aged people in Hwasun-gun, Chollanam-do, Republic of Korea. Fecal samples were collected monthly from November 1996 to October 1997 and examined for enteric parasites. To detect oocysts of C. parvum, the modified acid-fast stain was applied. To determine effects of climatic factors, local weather reports were collected. The overall oocyst prevalence during 1 year was 57.0% (77 of 135), and was significantly higher (P < 0.0001) in aged people--those aged 50-59 years (80.0%) and those aged 60-69 years (69.0%)--than in younger groups. No significant difference (P > 0.05) was noted between men and boys (53.6%) and women and girls (59.5%), but significant (P < 0.05) household clustering was recognized. People aged > 50 years tended to be more repeatedly positive than people in the younger group. The rate varied monthly from 7.8 to 20.0% (average, 12.6%), with significantly higher (P < 0.05) rates in spring than in summer and winter months. This seasonality had little relation with temperature (r = 0.04), but a weak correlation was found with rainfall (r = 0.4). It is of special interest that cryptosporidiosis is highly endemic among the aged population.     

新生儿TSH测定与成人尿碘测定的对比

本文报道了用纸片法测定沈阳碘缺乏病区新生儿 TSH6498人,结果显示亚临床甲低人群占11.9%,与尿碘测定显示结果12.0%是一致的。进一步比较各县区新生儿 TSH 值与成人尿碘值,发现二者之间成高度负相关,且有较好的直线回归关系。笔者对两种测定方法做了简单对比,认为新生儿纸片TSH 测定是碘缺乏病监测的可靠指标,建议在我国逐步推广应用。     

Role of mitogen-activated protein kinases in hydrogen peroxide-induced cell death in osteoblastic cells

Oxidative stress is known to induce cell death in a wide variety of cell types, apparently by modulating intracellular signaling pathways. However, the underlying mechanism by which oxidants induce cell death remains unclear. The present study was undertaken to determine the role of the mitogen-activated protein kinase subfamilies in hydrogen peroxide (H2O2)-induced cell death of osteoblastic cells. H2O2 resulted in a time- and dose-dependent cell death, which was, in part, attributed to apoptosis. H2O2-induced cell death was prevented by iron chelator, hydroxyl radical scavengers. But H2O2-induced cell death was not affected by 3-aminobenzamide, an inhibitor of poly (ADP-ribose) polymerase activation. H2O2 treatment caused a transient activation of extracellular signal-regulated kinase (ERK), followed by sustained activation. Cell death induced by H2O2 was prevented by PD98059, an inhibitor of ERK upstream kinase MEK1/2. But H2O2 induced a transient activation of p38 and c-Jun N-terminal kinase (JNK) without sustained activation and inhibitors of these kinses were not effective in preventing the cell death. H2O2 increased Bax expression and produced hyperpolarization of mitochondrial membrane potential and its effect was prevented by PD98059. The ERK activation and cell death induced by H2O2 were not dependent on the phosphorylation of epidermal growth factor receptor. Taken together, these findings suggest that the ERK signaling pathway plays an active role in mediating H2O2-induced apoptosis of osteoblasts and functions upstream of mitochondria-dependent pathway to initiate the apoptotic signal.     

11C-PIB在轻度认知障碍及阿尔茨海默病诊断中的价值及其影响因素

目的研究¹¹C-匹兹堡化合物B(PIB)在轻度认知障碍(MCI)与阿尔茨海默病(AD)患者诊断中的应用价值及可能影响¹¹C-PIB结合的因素。方法回顾性分析2017年1月至2019年12月期间在陆军军医大学大坪医院行¹¹C-PIB PET显像的6例认知功能正常患者(NC)[男、女各3例,年龄(64.5±12.3)岁]、11例MCI患者[男4例,女7例,年龄(64.5±9.8)岁]和21例AD患者[男7例,女14例,年龄(68.1±9.1)岁]对¹¹C-PIB的摄取情况,采用标准摄取值比值(SUVR)法及视觉分析评估¹¹C-PIB在患者脑皮质的分布区域和结合量,并收集患者相关临床资料[包括年龄、性别、文化程度、认知障碍程度、神经心理学量表评分、血管危险因素(VRF)、载脂蛋白E(ApoE)基因等]。采用单因素方差分析或Fisher确切概率法进行组间比较,两两比较采用最小显著差异t检验,采用多元线性回归分析可能影响11C-PIB结合的因素。结果NC、MCI及AD组各脑叶组间比较SUVR差异均有统计学意义(3组各脑叶SUVR均值范围:1.16~1.26、1.19~1.35和1.40~1.61;F值:5.331~9.279,均P<0.05)。NC组与PIB阳性的MCI患者比较,后扣带回及楔前叶SUVR差异均有统计学意义(1.20±0.15与1.50±0.12,1.18±0.15与1.59±0.13;F值:6.389和10.668,t值:-2.33和-3.10,均P<0.05);PIB阳性的MCI与PIB阳性的AD比较各脑叶SUVR差异均无统计学意义(t值:-1.29~-0.51,均P>0.05)。视觉分析结果显示,AD组额叶[85.7%(18/21)]、后扣带回[85.7%(18/21)]、楔前叶[81.0%(17/21)]、颞叶[81.0%(17/21)]和枕叶[47.6%(10/21)]PIB阳性率明显高于MCI组(4/11、4/11、4/11、3/11和1/11;均P<0.05)。多元线性回归分析示认知障碍程度是影响各脑叶SUVR的独立危险因素(b值:0.377~0.536,均P<0.05),携带ApoEε4基因是影响楔前叶SUVR的独立危险因素(b=0.290,P<0.05)。结论¹¹C-PIB有助于临床对MCI及AD患者的诊断;认知障碍程度及ApoEε4基因携带是影响¹¹C-PIB结合的独立危险因素。     

A Tissue Mimicking Polyacrylamide Hydrogel Phantom for Visualizing Thermal Lesions Generated by High Intensity Focused Ultrasound

An optically transparent tissue-mimicking (TM) phantom whose acoustic properties are close to those of tissue was constructed for visualizing therapeutic effects by high intensity focused ultrasound (HIFU). The TM phantom was designed to improve a widely used standard bovine serum albumin (BSA) polyacrylamide hydrogel (PAG), which attenuated ultrasound far less than tissue and, unlike tissue, did not scatter ultrasound. A modified recipe has been proposed in the study by adding scattering glass beads with diameters of 40–80 μm (0.002% w/v) and by raising the concentration of acrylamide (30% v/v). The TM BSA-PAG constructed has an acoustic impedance of 1.67 MRayls, a speed of sound of 1576 m/s, an attenuation coefficient of 0.52 dB/cm at 1 MHz, a backscattering coefficient of 0.242 × 10⁻³ 1/sr/cm at 1 MHz and a nonlinear parameter (B/A) of 5.7. These parameters are close to those of liver. The thermal and optical properties are almost the same as the standard BSA-PAG. The characteristic features of the thermal lesions by HIFU were observed to be more accurately visualized in the TM BSA-PAG than in the standard BSA-PAG. In conclusion, the proposed TM BSA-PAG acoustically mimics tissue better than the standard BSA-PAG and is expected to be preferentially used for assuring if a clinical HIFU device produces the thermal lesion as planned.     

Prevalence of primary immunodeficiency in Korea

This study represents the first epidemiological study based on the national registry of primary immunodeficiencies (PID) in Korea. Patient data were collected from 23 major hospitals. A total of 152 patients with PID (under 19 yr of age), who were observed from 2001 to 2005, have been entered in this registry. The period prevalence of PID in Korea in 2005 is 11.25 per million children. The following frequencies were found: antibody deficiencies, 53.3% (n = 81), phagocytic disorders, 28.9% (n = 44); combined immunodeficiencies, 13.2% (n = 20); and T cell deficiencies, 4.6% (n = 7). Congenital agammaglobulinemia (n = 21) and selective IgA deficiency (n = 21) were the most frequently reported antibody deficiency. Other reported deficiencies were common variable immunodeficiencies (n = 16), X-linked agammaglobulinemia (n = 15), IgG subclass deficiency (n = 4). Phagocytic disorder was mostly chronic granulomatous disease. A small number of patients with Wiskott-Aldrich syndrome, hyper-IgE syndrome, and severe combined immunodeficiency were also registered. Overall, the most common first manifestation was pneumonia. This study provides data that permit a more accurate estimation PID patients in Korea.