Transmission of multidrug-resistant tuberculosis in Shanghai: roles of residential status.

SETTING: Shanghai is a mega city where 39% of the population comprises internal migrants. OBJECTIVE: To examine the different roles played by migrants and permanent residents in the transmission of multidrug-resistant tuberculosis (MDR-TB). DESIGN: We conducted a population-based cohort study to assess MDR-TB transmission in Shanghai between 1 January 2009 and 31 December 2012 using genotyping and geospatial analyses. RESULTS: A total of 367 MDR-TB cases formed the study cohort. Significant differences between MDR-TB cases who were internal migrants and those who were permanent residents were found with regard to age, sex, region, genetic characteristics and treatment outcomes. Permanent residents had a higher transmission rate than internal migrants (OR 3.36, 95%CI 1.86-6.09). Permanent residents and genotypic clustering cases had similar clusters in central downtown and some parts of suburban areas. Most of the clusters of internal migrants were found in rural areas bordering suburban areas. Clusters of genotypic non-clustering cases showed patterns that closely matched those of internal migrants, suggesting acquired drug resistance in migrants. CONCLUSION: In Shanghai, permanent residents were significantly associated with recent transmission of MDR-TB in central downtown areas. Clustered cases of internal migrants in rural areas were most likely to have contracted MDR-TB through acquired resistance.

Prevalence of motor problems in children with attention deficit hyperactivity disorder in Hong Kong.

INTRODUCTION: Local data on the occurrence of motor problems in children with attention deficit hyperactivity disorder are not available but an understanding of this important issue may enable better planning of medical services. We aimed to determine the prevalence of motor problems in children with attention deficit hyperactivity disorder in a local population. METHODS: In this descriptive cross-sectional study, children aged 6 to 9 years diagnosed with attention deficit hyperactivity disorder over a period of 6 months from 1 July to 31 December 2011 were recruited from the Joint Paediatric and Child Psychiatric ADHD Program in New Territories East Cluster in Hong Kong. Movement Assessment Battery for Children and Developmental Coordination Disorder Questionnaire-Chinese version were used to determine the presence of motor problems. RESULTS: Data from 95 participants were included in the final analysis. The number of children who had no, borderline, or definite motor problems was 63, 15, and 17, respectively. It is estimated that up to one third of local children with attention deficit hyperactivity disorder might have developmental coordination disorder. CONCLUSIONS: Motor problems are common in local children with attention deficit hyperactivity disorder and figures are comparable with those from other parts of the world. Despite the various limitations of this study, the magnitude of the problem should not be overlooked.

Health-related quality of life of children with epilepsy in Hong Kong: how does it compare with that of youth with epilepsy in Canada?

OBJECTIVE: The primary aim of our study was to compare the health-related quality of life (HRQL) of children with epilepsy in Hong Kong with that of children with epilepsy in Canada, and to explore possible factors affecting these findings. A second interest was to determine agreement between proxy reports and self-ratings among children with epilepsy in Hong Kong, compare these with findings in Canada, and identify factors that influence the concordance. METHODS: Child self-report and parent-proxy questionnaires on an epilepsy-specific HRQL measure, appropriately translated and validated in Chinese, were administered to 266 Hong Kong children and their parents. An unpaired t test was used to compare the scores with published results from 381 Canadian children and their parents, who used the original English version of the measure. Demographic characteristics of the two groups were compared using t tests, chi2 tests, and Fisher's exact tests. Agreement between parents' and children's scores was evaluated with intraclass correlation coefficients (ICCs) and standardized response means (SRMs). The total HRQL score differences between parents and children in Hong Kong were compared with those in Canada using an unpaired t test. Factors that might affect the parent-child score difference were studied using Pearson correlation analysis, chi2 test, and analysis of variance. Factors studied included: sex, current age, age at diagnosis, duration of epilepsy, number of antiepileptic drugs used, type of seizure, seizure severity, cognition of the child, the type of school attended, presence of neurological problems, presence of behavioral problems, recent health care usage, education and employment status of both parents, housing status of the family, and relationship of the proxy respondent to the child. RESULTS: (1) In contrast to the Canadian sample, Hong Kong children with epilepsy were older (P<0.01), had a longer duration of epilepsy (P<0.01) and less severe seizures (P<0.01), and were more likely to attend normal schools (P<0.01). Children in Hong Kong reported more interpersonal/social difficulties (P<0.01), more worries (P<0.01), and more secrecy about their epilepsy (P<0.01). Parents in Hong Kong believed that their children perceived more worries (P<0.01) and were more secretive about their epilepsy (P<0.01). (2) Moderate to good agreement between parent-proxy response scores and child self-report scores was demonstrated (ICC=0.50-0.69, SRM=0.19-0.33). The total HRQL score differences between parent and child in Hong Kong were not different from those in Canada. None of the factors studied were related to the parent-child score difference. CONCLUSIONS: Youth with epilepsy in Hong Kong and their parents reported poorer quality of life than children with epilepsy in Canada. Further studies are necessary to identify the determinants of HRQL in children with epilepsy in different cultures. Acceptable agreement between the two ratings suggests that proxy reports can be used when child self-reports cannot be obtained.

Prevalence study of cerebral palsy in Hong Kong children.

OBJECTIVES: To investigate the prevalence of cerebral palsy in local children aged 6 to 12 years and to evaluate service utilisation by those children who attend mainstream schools. DESIGN: Cross-sectional survey. SETTING: Mainstream primary schools and special needs schools in Hong Kong. PARTICIPANTS: Headmasters or headmistresses of special needs schools, and various organisations that provide services to children with cerebral palsy in the school year September 2003 to June 2004. MAIN OUTCOME MEASURES: Prevalence of cerebral palsy and support services used by children with cerebral palsy who attend a mainstream school. RESULTS: Of 435 572 children, 578 with cerebral palsy were identified. The overall point prevalence was 1.3 per 1000 children. The age-specific prevalence rate varied from 1.04 to 1.50 per 1000 children. Approximately 38% of children with cerebral palsy attended a mainstream school. Among those studying in special needs schools, 96% attended a school for the physically handicapped or a school for the severely mentally handicapped. Among 219 children with cerebral palsy in mainstream schools, 57 (26%) received educational support, and 134 (61%) received out-patient therapy support. Only 12% received both supporting services. No educational or therapeutic support was received by 26% of children. CONCLUSIONS: Compared with overseas data, the low prevalence of cerebral palsy detected in local children in this investigation may be due to the differences in study design or a genuinely low prevalence. Setting up a cerebral palsy registry could help monitor the local prevalence of this childhood disability more accurately, thereby providing more reliable information for planning support services for this subgroup of children.

On differential variability of expression ratios: improving statistical inference about gene expression changes from microarray data.

We consider the problem of inferring fold changes in gene expression from cDNA microarray data. Standard procedures focus on the ratio of measured fluorescent intensities at each spot on the microarray, but to do so is to ignore the fact that the variation of such ratios is not constant. Estimates of gene expression changes are derived within a simple hierarchical model that accounts for measurement error and fluctuations in absolute gene expression levels. Significant gene expression changes are identified by deriving the posterior odds of change within a similar model. The methods are tested via simulation and are applied to a panel of Escherichia coli microarrays.

Enhanced accuracy of needle placement in horizontal stereotactic core biopsy by a plastic slot.

Horizontal stereotactic core biopsy can be used in the investigation of clinically occult mammographic abnormalities especially when breast thickness is less than 3 cm. We designed a 6-mm plastic slot that can be inserted between the bushing and the biopsy gun to enhance the accuracy of needle placement within the lesion. With this device, the centre of the lesion can be targeted at the centre of the biopsy trough. We advocate the use of this piece of small, simple and inexpensive instrument in every case of horizontal stereotactic core biopsy.

Large needle core biopsy--avoidance of biopsy table bombardment by the biopsy needle in stereotactic guided breast biopsy.

Table bombardment by automated biopsy needle is an occasional technical problem during stereotactic core biopsy of the breast. It is most commonly encountered in small breasts and when lesions are close to the biopsy table. A reference chart is devised for stereotactic core biopsy using an add-on erect stereotactic biopsy table and automated spring-loaded biopsy gun. The chart serves as a reference for pre-biopsy assessment of the feasibility of core biopsy in the vertical approach due to the constraints of lesion depth and breast thickness. It allows easy and quick reference for the required needle length input for the stereotactic system to prevent table bombardment.

Analysis of expressed sequence tags from a fetal human heart cDNA library.

Single-pass sequencing of randomly selected cDNA clones to generate expressed sequence tags (ESTs) has been widely used to identify novel genes and to study gene expression in a variety of tissues. We have generated 2244 ESTs from a human fetal heart library (GenBank Accession Nos. R30692-30774 and R56965-58824), which we present in this report. Of these, 51.7% showed no homology to known genes or were similar only to other ESTs, while 48.4% demonstrated homology to known transcripts. A total of 764 ESTs corresponding to known genes were used to study gene expression patterns in the fetal heart and to analyze differences in these patterns from those observed in the adult heart. These analyses demonstrate the utility of ESTs and sequence-tagged clones in comparative studies of gene expression in the cardiovascular system, and they reveal that differential gene expression underlies the structural and functional characteristics of the developing heart.

Sister-chromatid exchanges in lymphocytes from methimazole-induced hypothyroid mice.

The inhibitory effect of an antithyroid drug on mouse T lymphocytes was investigated. Inbred C57BL/6 mice were provided with an antithyroid drug, methimazole, for 2, 4 and 6 weeks and the in vitro responses of the lymphocytes were studied. The proliferative responses of T lymphocytes from the spleen of methimazole (MMI)-treated mice significantly (p < 0.05) decreased following concanavalin A stimulation, and the inhibitory effect became prominent with the increased duration of MMI treatment. A concomitant increase in the frequency of induced sister-chromatid exchanges was also observed in these T lymphocytes. When the splenocytes were stimulated with concanavalin A for 24 h, their ability to produce interleukin-2 (IL-2) was significantly decreased (p < 0.05). The results indicated that methimazole interfered with the normal proliferation of T lymphocytes by suppressing the production of IL-2, a cytokine also known as T cell growth factor, as well as inducing a higher incidence of sister-chromatid exchange during cell division.

Activation of peritoneal macrophages by polysaccharopeptide from the mushroom, Coriolus versicolor.

Polysaccharopeptide (PSP) is a substance produced by an edible mushroom, Coriolus versicolor which has been claimed to possess antitumor activity. However, neither tumoricidal activity nor cytotoxicity was observed when five tumor cell lines and mouse peritoneal macrophages were cultured in vitro in the presence of 2.5-10 micrograms/ml PSP. An increase in the production of reactive nitrogen intermediates, reactive oxygen intermediates (superoxide anions) and tumor necrosis factor was measured in peritoneal macrophages collected from inbred C57 mice which had received PSP in the drinking water for 2 weeks. Northern blot analysis also demonstrated that PSP activated the transcription of tumor necrosis factor gene in these cells, indicating that PSP exerted an immunomodulatory effect on the defensive cells.

Repressed activity of peritoneal macrophages in methimazole-induced hypothyroid mice.

In this study we compared the functions of normal peritoneal macrophages with those from methimazole-induced hypothyroid C57BL/6 mice. Methimazole (MMI) suppressed the expression of the tumor necrosis factor (TNF) gene in peritoneal macrophages (MAM) at both transcriptional and translational levels. The kinetics of TNF synthesis by MAM following in vivo and in vitro lipopolysaccharide (LPS) challenge were different, but both treatments resulted in significant decreases (P < 0.05) in TNF mRNA and protein after 60 min. Similarly, the production of reactive nitrogen and oxygen intermediates by MAM were significantly (P < 0.05) lower compared with control macrophages (CAM). In addition, the serum TNF protein was significantly lower (P < 0.05) in MMI-treated mice following intravenous LPS challenge for 90 min. These data suggested that peritoneal macrophages were inactivated in MMI-induced hypothyroid mice.