Rupture of the posterior tibial tendon: CT and surgical findings

Computed tomography (CT) was performed in 42 patients with 49 clinically suspected tears of the posterior tibial tendon. Twenty-eight of the 49 suspected tears were subsequently surgically explored and repaired. Three patterns of tendon abnormalities were recognized on CT scans: type I-intact, hypertrophied, heterogeneous tendon; type II-attenuated tendon; and type III-absence of a portion of a tendon. Types I and II correlated with partial rupture seen during surgery, and type III correlated with complete rupture of the tendon. CT findings were accurate in 96% of the patients who underwent surgery. In four cases (14%), tendon rupture was seen on CT scans, but the extent of the injury was underestimated and the rupture was misclassified. Reactive periostitis of the distal tibia was seen in 71% of diseased tendons and may represent an important factor in the diagnosis of tendon rupture.     

Polymorphisms in manganese superoxide dismutase and catalase genes: functional study in Hong Kong Chinese asthma patients

BACKGROUND: Reactive oxygen species may contribute to the pathogenesis of asthma. Functional genetic polymorphisms of antioxidant enzymes, superoxide dismutase (SOD) and catalase are good candidates for asthma susceptibility. OBJECTIVE: To investigate the association of the manganese-containing form of SOD (MnSOD) gene at amino acid position 16 (Val16Ala) and catalase gene in the promoter at A-21T and C-262T polymorphisms and asthma in a Hong Kong Chinese population. METHODS: The association study was conducted in a case-control design in asthma patients (n=251) and healthy controls (n=316) by genotyping. The functional significance was assessed by determining erythrocyte SOD and catalase activity. RESULTS: The Val allele of MnSOD at Val16Ala and the A allele of catalase gene at A-21T were not different between patients and controls, while the C allele of catalase gene at C-262T was found to be significantly different between patients and controls (P=0.033). The less frequent variant of catalase gene (-262T) was found to be protective from the development of asthma in a Hong Kong Chinese non-smoking population (adjusted odds ratio=0.35, 0.15-0.85; P=0.017). Asthma patients had elevated erythrocyte SOD and catalase activities in comparison with healthy controls (P<0.01). However, their activities were not associated with different genotypes within healthy controls or asthma patients. CONCLUSION: This is the first report showing that SOD and catalase functional activities are not associated with their respective genetic polymorphisms but related to the presence of asthma in a Hong Kong Chinese population.     

The path to care in autism: Is it better now?

Parents of children with autism often report problems associated with obtaining a diagnosis of their child's condition, family support, information, and appropriate services. To evaluate any changes in the situation over the last two decades, the families of all members of the West Midlands Autistic Society, age 19 years and below, were asked to fill in a questionnaire that covered aspects of detection, diagnosis, help and information received, and educational provision. Responses were obtained from 127 families, the children of whom formed an older group ages 10 years and above (n=67) and a younger group ages 9 years and below (n=61). Findings show that there have been improvements for the younger group in some areas, such as earlier referral, diagnosis, and statementing. However, the situation with respect to advice given by professionals and the support and provision available after referral is still much the same as that experienced by families of the older group of children. Many difficulties and hurdles remain which hinder parents and children on the path to care in autism.     

Heroin-Induces Differential Protein Expression by Normal Human Astrocytes (NHA)

Heroin use is postulated to act as a cofactor in the neuropathogenesis of human immunodeficiency virus (HIV-1) infection. Astrocytes, integral components of the CNS, are reported to be susceptible to HIV-1 infection. Upon activation, astrocytes release a number of immunoregulatory products or modulate the expression of a number of proteins that foster the immunopathogenesis of HIV-1 infection. However, the role of heroin on HIV-1 infectivity and the expression of the proteome of normal human astrocytes (NHA) have not been elucidated. We hypothesize that heroin modulates the expression of a number of proteins by NHA that foster the neuoropathogenesis of HIV-1 infection. We utilized LTR amplification and the p24 antigen assay to quantitate the effect of heroin on HIV-1 infectivity while difference gel electrophoresis (DIGE) combined with protein identification through high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) to analyze the effects of heroin on the proteomic profile of NHA. Results demonstrate that heroin potentiates HIV-1 replication in NHA. Furthermore, heroin significantly increased protein expression levels for protein kinase C (PKC), reticulocalbin 1 precursor, reticulocalbin 1, tyrosine 3-monooxgenase/tryptophan 5-monooxgenase activation protein, chloride intracellular channel 1, cathepsin D preproprotein, galectin 1 and myosin light chain alkali. Heroin also significantly decreased protein expression for proliferating cell nuclear antigen, proteasome beta 6 subunit, tropomyosin 3, laminin receptor 1, tubulin alpha 6, vimentin, EF hand domain family member D2, Tumor protein D54 (hD54), ATP synthase, H+ transporting, mitochondrial F1 complex and ribosomal protein S14. Identification of unique, heroin-induced proteins may help to develop novel markers for diagnostic, preventative and therapeutic targeting in heroin using subjects.     

Mechanisms of connective tissue damage by crystals containing calcium

From available clinical, radiographic, and synovial fluid findings, coupled with in vivo radiolabelled crystal turnover data and in vitro experimental data, a hypothesis has been formulated relative to the pathogenesis of BCP crystal deposition diseases (Fig. 2). Synovial lining cells phagocytose BCP crystals and particulate collagens in the joint fluid. During and/or after internalization these cells are stimulated in a variety of ways: 1) protease synthesis and secretion is relentlessly stimulated, which may damage joint tissues producing clinically evident loss of collagenous tissues including cartilage, bone, and tendon, and which may release additional amounts of crystals and particulate collagens into the synovial fluid, completing a vicious cycle; 2) PGE2 production is greatly augmented; 3) DNA synthesis is stimulated as a result of increased inositol phospholipid turnover and intracellular crystal dissolution. The increased number of synovial cells also augments the total local generation of proteases and prostenoids. Mechanical factors such as trauma or joint overuse also contribute to the pathogenesis of joint destruction as discussed in the article on the clinical aspects of BCP crystal deposition.     

Partial replication of a DRD4 association in ADHD individuals using a statistically derived quantitative trait for ADHD in a family-based association test.

BACKGROUND: Previous research found an association between single nucleotide polymorphisms (SNPs) in the promoter region of DRD4 and statistically derived phenotypes generated from attention-deficit/hyperactivity disorder (ADHD) symptoms. We sought to replicate this finding by using the same methodology in an independent sample of ADHD individuals. METHODS: Four SNPs were genotyped in and around DRD4 in 2631 individuals in 642 families. We developed a quantitative phenotype at each SNP by weighting nine inattentive and nine hyperactive-impulsive symptoms. The weights were selected to maximize the heritability at each SNP. Once a quantitative phenotype was generated at each SNP, the screening procedure implemented in PBAT was used to select and test the five SNPs/genetic model combinations with the greatest power to detect an association for DRD4. RESULTS: One of the four SNPs was associated with the quantitative phenotypes generated from the ADHD symptoms (corrected p-values = .02). A rank ordering of the correlation between each of the ADHD symptoms and the quantitative phenotype suggested that hyperactive-impulsive symptoms were more strongly correlated with the phenotype; however, including inattentive symptoms was necessary to achieve a significant result. CONCLUSIONS: This study partially replicated a previous finding by identifying an association between rs7124601 and a quantitative trait generated from ADHD symptoms. The rs7124601 is in linkage disequilibrium (LD) with the SNPs identified previously. In contrast to the previous study, this finding suggests that both hyperactive-impulsive and inattentive symptoms are important in the association.     

Practice of orthokeratology by a group of contact lens practitioners in Hong Kong

Purpose: The aim of the study was to provide information about the characteristics of three main types of orthokeratology (ortho‐k) lenses used in Hong Kong and to report on their performance based on the clinical impressions of a group of ortho‐k practitioners. Method: Twelve ortho‐k practitioners were interviewed between 1 March and 30 June 2001. Results: Most ortho‐k lenses were ordered from three manufacturers: DreimLens, Fargo and Contex. The median maximum myopia reduction reported for DreimLens, Contex and Fargo lenses were 6.25 D, 6.00 D and 4.50 D respectively. The time to reduce myopia by up to 4.00 D could be up to three weeks for Contex and DreimLens and up to four weeks for Fargo. For reduction of myopia by up to 4.00 D, the treatment usually required only one or two lenses per eye for all three types of lenses. The incidence of lens binding and lens tightening after achieving the optimal reduction was reported to be higher with the DreimLens design. Good centration, less lens binding, relatively lower incidence of complications and lens tightening after achieving the optimal reduction were reported with the Fargo lenses. Conclusions: DreimLens tended to be more effective for myopia reduction. However, some practitioners were concerned with the aggressiveness of myopia reduction using this lens design and the higher potential for ocular complications. Selection of the lens design is dependent on various factors, in particular, practitioners need to be comfortable with the design they choose and to consider the needs of their patients and the final goal of the treatment.     

Defining the Role of Surgery for Primary Gastrointestinal Tract Melanoma

Objective The objective of the study was to determine the outcomes for primary gastrointestinal melanomas (PGIM). Material and methods The Surveillance, Epidemiology, and End Results database (1973–2004) was queried. Results Overall, 659 cases of PGIM were identified. The annual incidence of PGIM was approximately 0.47 cases per million in 2000. Overall median survival time was 17 months. Tumors were identified in the oral–nasopharynx (32.8%), anal canal (31.4%), rectum (22.2%), esophagus (5.9%), stomach (2.7%), small bowel (2.3%), gallbladder (1.4%), and large bowel (0.9%). Univariate analysis demonstrated age, tumor location, stage, surgery, and lymph node status were significant predictors of improved survival. MST has not been reached for tumors located in the large bowel, while tumors located in the stomach demonstrated the shortest median survival (5 months). Improvement in MST was observed for those patients undergoing surgical resection. The presence of lymph node involvement conferred a poorer prognosis. Multivariate analysis of the cohort identified that location, advanced tumor stage, failure to undertake surgical resection, positive lymph node status, and age were all independent predictors of poorer outcome. Conclusion PGIM occurs most often in the oral–nasopharynx and anal canal. Surgical extirpation is the only identifiable treatment modality that significantly improves survival.     

Retinal degeneration associated with RDH12 mutations results from decreased 11-cis retinal synthesis due to disruption of the visual cycle

Human Molecular Genetics