Melanotic Neuroectodermal Tumor of Infancy Occurring in the Left Thigh of a 6-Month-Old Female Infant

We report an exceptional case of melanotic neuro-ectodermal tumor of infancy (MNTI) occurring in the soft tissue of the left thigh of a 6-month-old female infant. The tumor consisted mainly of small round cells (neuroblasts) arranged in cords and nests that were separated by broad fibrovascular areas. In addition, there were a few medium-sized tumor cells containing melanin pigment (melano-cytic cells) that in electron microscopy contained melanosomes as well as tonofilaments. Both tumor cell types immunostained for neuron-specific enolase (NSE) and vimentin, and the melanocytic cells reacted additionally with the antikeratin antibody KL1. Within the tumor stroma, neurofilament- and S-100-protein-positive neural cells and vimentin- and desmin-positive myofibroblasts were seen. Although densecore granules were demonstrated ultrastructurally in some neuroblasts, no immunostaining for chromogranin A, Leu-7, serotonin, or regulatory peptides was found. MNTI located in an extremity can be confused with malignant small round and blue cell tumors of childhood. The distinction between MNTI and these tumors is of clinical significance because MNTI, in most cases, is a benign tumor that, in contrast to the latter, can be cured by complete excision. The presence of a biphasic cell population with neuroblasts and melanocytic cells must be considered the main diagnostic feature of MNTI.     

Birth factors and laterality: Effects of birth order,parental age,and birth stress on four indices of lateral preference

As an alternative to genetic theories of handedness, some theorists have offered an environmental mechanism, associated with birth stress, for the appearance of left-handedness. They suggest that brain damage as a result of birth difficulties can lead to a switch in hand preference from the right side to the left side. Consequently, one should find more left-handers in groups where the probability of the occurrence of birth stress is greater. Three studies are presented which explore the laterality of not only hand but also foot, eye, and ear, in a total of 5161 individuals, in an attempt to assess any relationship to birth stress. Maternal age seems to predict deviations from dextrality, dependent on the sex of the offspring, while paternal age and birth order do not. The use of a direct measure of conditions predisposing toward birth stress suggests that these results depend on prenatal or perinatal environmental trauma rather than chromosomal factors.This research was supported by grants from the Medical Research Council of Canada and from the Natural Sciences and Engineering Research Council of Canada, and represents an equal and shared contribution of both authors.     

Using linked markers to infer the age of a mutation

Advances in sequencing and genotyping technologies over the last decade have enabled geneticists to easily characterize genetic variation at the nucleotide level. Hundreds of genes harboring mutations associated with genetic disease have now been identified by positional cloning. Using variation at closely linked genetic markers, it is possible to predict the times in the past at which particular mutations arose. Such studies suggest that many of the rare mutations underlying human genetic disorders are relatively young. Studies of variation at genetic markers linked to particular mutations can provide insights into human geographic history, and historical patterns of natural selection and disease, that are not available from other sources. We review two approaches for estimating allele age using variation at linked genetic markers. A phylogenetic approach aims to reconstruct the gene tree underlying a sample of chromosomes carrying a particular mutation, obtaining a “direct” estimate of allele age from the age of the root of this tree. A population genetic approach relies on models of demography, mutation, and/or recombination to estimate allele age without explicitly reconstructing the gene tree. Phylogenetic methods are best suited for studies of ancient mutations, while population genetic methods are better suited for studies of recent mutations. Methods that rely on recombination to infer the ages of alleles can be fine‐tuned by choosing linked markers at optimal map distances to maximize the information available about allele age. A limitation of methods that rely on recombination is the frequent lack of a fine‐scale linkage map. Maximum likelihood and Bayesian methods for estimating allele age that rely on intensive numerical computation are described, as well as “composite” likelihood and moment‐based methods that lead to simple estimators. The former provide more accurate estimates (particularly for large samples of chromosomes) and should be employed if computationally practical. Hum Mutat 18:87–100, 2001. © 2001 Wiley‐Liss, Inc.     

Stimulation of cranial vessels excites nociceptive neurones in several thalamic nuclei of the cat

Summary Extracellular recordings were made in the thalamus of cats anaesthetized with chloralose and urethane following electrical, mechanical and chemical stimulation of the superior sagittal sinus or middle meningeal artery. Facial receptive fields were looked for using electrical and mechanical stimuli. The locations of fifty-six cells were verified histologically. Twenty six cells were located in the ventroposteromedial nucleus (VPM) and six in its ventral periphery (VPMvp). All units in VPM had facial receptive fields, usually involving the first trigeminal division. Cells with nociceptive receptive fields or responding to the craniovascular application of bradykinin were often found in the periphery or “shell” region of VPM. Other craniovascular nociceptive cells were found in VPMvp, in the posterior group and in the intralaminar complex. This study shows that craniovascular afferents in the cat project to several thalamic nuclei and implicate VPM especially in craniovascular nociception.     

“Cross-over” duplication of middle cerebral artery,agenesis of internal carotid artery and saccular aneurysms

Summary The authors describe a patient with anomalous branches of the left internal carotid artery, cross-over duplication of its middle cerebral artery and agenesis of the contra-lateral internal carotid artery associated with two aneurysms successfully clipped. Pertinent literature is reviewed.     

Influence of age on serum protein binding of propranolol

Summary The extent of propranolol protein binding was determined in three different age groups of healthy drug-free caucasian males. Volunteers selected for study were 6–15 years old, 25–36 years old and 68–76 years old. Ten milliliters of blood were obtained via venipuncture and collected in glass tubes from the subjects after an overnight fast. Binding determinations were performed by equilibrium dialysis using radiolabelled propranolol. Serum albumin and ₁-acid glycoprotein concentrations were determined in all subjects by radial immunodiffusion. The results obtained showed wide intersubject variability in the binding ratio of propranolol and serum concentrations of ₁-acid glycoprotein. Mean albumin serum concentration was found to be significantly lower in the elderly group as compared to the adult and pediatric groups (p<0.02). A positive correlation was found between the binding ratio of propranolol and the serum concentration of ₁-acid glycoprotein in all the subjects (r=+0.66,p<0.005). No significant correlation was found between the binding ratio of propranolol and the serum concentration of albumin (r=–0.03,p<0.88). These data suggest that the extent of propranolol binding is influenced primarily by serum concentrations of ₁-acid glycoprotein and not by differences in age.     

Prevalence of mental disorder in an urban population in central Sweden

The principal reason for this epidemiological study was the lack of psychiatric morbidity studies in a predominantly urban population, by psychiatrists in direct interviews. The psychiatric examination, covering 1970-71, included a representative selection of 2,283 persons, 18-65 years old from "former" Stockholm County, and the 12-month prevalence of mental disorders was measured. The total of non-participants was 12%. Forty-seven percent had a psychiatric diagnosis - significantly more women (54%) than men (40%). Excluding the psychosomatic diagnoses, 31% of the population received a psychiatric diagnosis, which agrees closely with other contemporary studies of mental disorder in the Nordic countries. The primary diagnoses were: neuroses 26%, psychosomatic diagnoses 16%, schizophrenic/paranoid conditions or other psychoses 0.6%, affective disorders 0.2%, psychoorganic syndromes 1.2%, psychopathy 0.2%, character neurosis 1%, drug dependence 0.2% (as a primary or a secondary diagnosis 0.6%), alcoholism 1.4% (as a primary or a secondary diagnosis 3.1%) and mental retardation 0.4% (as a primary or a secondary diagnosis 0.8%).     

徐州市直属小学学生近视与教室光环境调查研究

目的 调查徐州市直属小学学生近视现状,分析教室光环境及学龄对儿童视力的影响。方法 采用整群抽样方法,运用标准对数视力表对直属小学学生进行视力检测;随机抽取4所学校,使用TES-1332A照度计测定教室光环境;计量资料采用t检验或方差分析;计数资料采用χ2检验,等级资料采用秩和检验分析其统计学差异。结果 2018年徐州市小学生近视检出率总体为49.84%(男生45.81%,女生53.88%),女生高于男生(χ2=52.001,P<0.05),且重度近视检出率更高(Z=7.795,P<0.05)。市直属小学生近视检出率54.18%,县区直属小学46.45%,市区高于县区(χ2=47.247,P<0.05)。不同年级近视发生情况不同,二～六年级近视检出率分别为36.03%,40.5%,48.45%,58.77%,65.4%,高年级近视发生率高于低年级(χ2趋势=384.766,P<0.05),且重度近视高于低年级(χ2=742.673,P<0.05)。各检测小学不同楼层间教室黑板以及桌面照度不同 (F=3.894,P<0.05) ,但均符合国家标准。结论 徐州市直属小学学生近视检出率较高,并随学龄延长而加重,女生更严重;监测学校教室光环境符合要求。改善和保护学生视力除了保障教室光环境合格和定期监测外,应进一步探讨影响学生视力的其他因素,共同促进学生视力健康。     

粤西某市城区寄宿学校中学生不良饮食行为现状与影响因素分析

目的 了解粤西某市城区寄宿的中学生饮食行为现状与影响因素,为探索干预方法提供依据。方法 自编调查问卷,2021年10月对某城区全部有食宿条件的10所中学,用分层抽样法现场调查547名初一至高二学生,对5种饮食行为与相关因素进行描述分析和logistic回归分析。结果 饮食的5种行为不良率从高到低依次为:吃外卖(49.0%)、不吃早餐(31.7%)、喝奶茶(24.3%)、吃夜宵(11.8%)、零食代餐(1.3%);“学生可支配费用少于100元/星期”“学校饭堂饮食口味评价——不满意”两个因素均能促成5种不良饮食行为发生(P<0.05),“饮食重要性感知意识——不重要”因素对“喝奶茶”“吃夜宵”行为影响强度最大(OR=4.386,P=0.019;OR=5.780,P=0.006);女生能促成“吃外卖”(OR=1.586,P=0.015)和“喝奶茶”(OR=1.770,P=0.010),“每星期可支配消费超过200元以上”能促成“吃外卖”和“吃夜宵”(OR=2.346,P=0.001;OR=2.585,P=0.009)。结论 城区寄宿学校中学生不良饮食行为问题突出,不满学校饭堂饮食口味对促发不良饮食行为影响最广,“认为饮食不重要”是促发不良行为产生的最强因素,亟须加强寄宿中学饮食支持条件的管理,加强学生饮食健康教育,控制当前城市寄宿学校中学的学生不健康饮食行为。