Testing genetic models for multiple symptoms: An application to the genetic analysis of liability to depression

A model is presented which allows for the contribution of genes and environment to categorical data on multiple symptoms. The model distinguishes between parameters needed to express the relationship between a latent trait and observed responses and the parameters required to represent the causes of variation in the latent trait. The regression of the latent trait on covariates may also be specified. The model is applied to symptoms of depression in 1983 pairs of adult female monozygotic and dizygotic twins. A model which allows only for polygenic variation in the latent trait is supported as well as the mixed model, which also allows for the effects of a major gene. The likelihood is significantly lower when all genetic effects are ascribed to a single gene. Practical limitations of the method are discussed.This research is supported by Grants AG04954, AA06781, GM32782, GM30250, and MH40828 from the National Institutes of Health. We are indebted to Dr. Greg Carey for his incisive discussion.     

Diversity of enteric viruses detected in patients with gastroenteritis in a tertiary referral paediatric hospital

The genetic diversity of enteric viruses co-circulating in a cohort of patients with viral gastroenteritis in a large tertiary paediatric hospital in London, UK, was determined. Multiple strains of noroviruses (NV), sapoviruses (SV) and astroviruses (HAsV) were detected in these patients, indicating the likelihood of multiple introductions from different sources, possible sub-clinical infections and simultaneous infection with different viruses in immunocompromised and other patients. Routine screening of immunocompromised patients and infection control procedures are important to prevent nosocomial infection.     

Cervicovaginal (Papanicolaou) smear findings in patients with malignant mixed Müllerian tumors

Malignant mixed Müllerian tumor is a rare neoplasm that occurs most frequently in elderly patients. It is characterized by a mixture of malignant epithelial and sarcomatous components. Little has been published about Papanicolaou smear findings pertaining to malignant mixed Müllerian tumors. We present our experience, with an emphasis on cytologic detail. Nine patients (median age, 65 yr) met our study criteria. All available smears and surgical specimens were reviewed. Four smears were positive for malignancy, with a sensitivity of 44% (3 adenocarcinoma, and 1 squamous-cell carcinoma, small-cell type). The results of our study showed that Papanicolaou smear findings pertaining to malignant mixed Müllerian tumors are seen in patients with advanced-stage disease with involvement of the lower uterine segment or cervix. The usual finding is large numbers of high-grade epithelial malignant cells in a necrotic background. The mesenchymal component rarely sheds cells visible on Papanicolaou smear.     

Localization of calcium ions in mixed synapses of Mauthner neurons during exposure to substances altering the conductivity of gap junctions

The pyroantimonate method was used to study the distribution of calcium ions in the mixed synapses of Mauthner neurons after exposure to substances altering the electrotonic conductivity of these synapses mediated by gap junctions (GJ). Ecdysone, an agent which increases GJ conductivity, produced precipitates of calcium pyroantimonate coating the whole postsynaptic surface of the GJ area, making them strongly asymmetrical. Precipitate granules were also seen to appear in the clefts of desmosome-like contacts (DLC). Chlorpromazine, which decreases GJ conductivity, produced precipitates in GJ clefts and on the pre- and postsynaptic membranes. No precipitate formed in DLC clefts. These results demonstrate that ecdysone acts as an agent selectively increasing GJ conductivity without affecting DLC function. Chlorpromazine had a double action, blocking conduction through both GJ and DLC. Thus, studies of agents altering GJ permeability require consideration of the possibility that they may interact with actin-containing structures also involved in the transport of the electrotonic signal.Translated from Morfologiya, Vol. 125, No. 3, pp. 32–35, May–June, 2004.     

Recalcified plasma as nutrient additive in mixed lymphocyte culture

Animal or human blood protein is a costly but necessary additive to tissue culture. This supplemental protein is provided by the addition of pooled serum or heparinized plasma to standard tissue culture media. Many blood centers store CPDA-1 anticoagulated plasma, a form that does not provide optimal support of mixed lymphocyte culture (MLC). The optimal amount of CaCl2 (1 ml of 1 M CaCl2/100 g) added to citrate plasma and the use of glass vessels result in a completely clotted product that is comparable in MLC support to commercially available pooled human serum. Laboratories that have access to CPDA-1 plasma can replace the growing demand for serum with recalcified plasma without sacrificing quality.     

In vivo and in vitro comparison of fire ant venom and fire ant whole body extract

Thirty-four patients with a history of immediate hypersensitivity to the sting of the imported fire ant were evaluated in a study designed to compare the diagnostic usefulness of fire ant whole body extract (WBE) preparations with that of fire ant venom (IFAV). Ninety-one percent ($\text{31}\text{34}$) of the hypersensitive patients skin tested with IFAV at a maximal concentration of 1:5 × 10³, $\text{v}\text{v}$, demonstrated a wheat equal to or greater than the histamine control. Fifty-three percent ($\text{18}\text{34}$) of the group were skin test positive to a WBE preparation. When the criteria for a positive skin test were relaxed, 82% of the hypersensitive group could be identified with the IFAWBE. A comparison of skin test results in sensitive patients revealed variability in the sensitivity of the WBE preparations utilized in the study. Leukocyte histamine release demonstrated a dose-response release of histamine with both IFAV and SIWBEa preparations. Specific venom antisera produced in rabbits identified a precipitin line of common identity in a gel-diffusion system containing IFAWBE and IFAV. This finding was verified by the competitive inhibition of IFAWBE with IFAV in a solid-phase radioimmunoassay system. Fire ant WBEs contain venom constituents and are effective diagnostic agents in up to 82% of patients with hypersensitivity to the sting of the imported fire ant. Marked variability in the responsiveness of sensitive patients to different WBE preparations mandates standardization of these diagnostic preparations.     

细胞因子在清肝化瘀汤治疗慢性粒细胞性白血病中的研究

目的观察中药清肝化瘀汤治疗慢性粒细胞性白血病(慢性期)的疗效,并探讨细胞因子水平变化的意义。方法收集45例慢性粒细胞性白血病慢性期患者(治疗组),用清肝化瘀汤治疗,观察患者的临床疗效、细胞因子水平。另用20名正常人作为对照(对照组)。结果治疗组完全缓解率40％,部分缓解率46.7％,总有效率86.7％。治疗组细胞因子水平中白介素2、可溶性白介素2受体、肿瘤坏死因子a治疗前后有显著差异(P<0.05);干扰素γ水平变化无显著差异。且与正常对照组比较无显著差异(P>0.05)。结论清肝化瘀汤有清热泻肝解毒、活血化瘀消癥的功效,研究结果显示,该药对慢性粒细胞性白血病慢性期(肝热血瘀型)疗效确切,其作用机理可能与改善细胞因子水平有关。     

Three rare cases of benign mixed tumour of the skin displaying mature bone and cartilage elements

Mixed tumour of the skin is a rare adnexal tumour of sweat gland origin, which can be benign or malignant. Histologically, it is defined by the presence of epithelial, myoepithelial and mesenchymal elements. The latter can take several forms, but both bone formation and cartilage formation are independently rare features. We present three rare cases of mixed tumour of the skin. Two of these displayed both mature bone and cartilaginous mesenchymal elements, while the third displayed mature bone formation without cartilage.     

六味地黄汤含药血清对海马神经元突触活动的影响

目的：研究六味地黄汤益智作用的机理。方法：应用血清药理学和电生理方法，观察六味地黄汤含药血清对原代培养大鼠海马神经元自发突触活动的影响。结果：含药血清作用48h可明显增加海马神经元自发动作电流(spontaneous action cur-rent,sAC)和微小兴奋性突触后电流(miniature excitatory post aynaptic currenl,mEPSC)的产生频率，但并不影响mEPSC的幅度。结论：六味地黄汤可作用于突触前位点对海马神经元突触活动产生调节作用，该作用可能是其调节海马神经元的兴奋性进而发挥益智作用的机制之一。     

中西医结合治疗急性脑梗塞疗效观察

根据中医血水相关理论 ,拟定活血利水煎为基本方 ,配用西药以防严重并发症 ,治疗急性脑梗塞 85例 ,并设单纯西药治疗组 6 0例作对照。结果表明 ,治疗组的临床疗效较对照组有非常显著性差异 (P <0 0 1) ,中药活血利水煎具有改善血液流变性 ,降高血压、高血糖、高血脂的作用。活血利水为脑梗塞急性期治疗大法