Rigid spine syndrome with fiber type disproportion.
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Biomedical subjects
Publications and source records attributed to E Tan.
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Hypergammaglobulinaemic purpura, first described by Waldenstrom, is a rare skin disease. The essential features are the presence of purpura with polyclonal hypergammaglobulinaemia. We describe a case of hypergammaglobulinaemic purpura occurring in a Chinese man with reticulate purpura and haemorrhagic blisters.
We report a study of the sensitization rate to sesquiterpene lactone (SL) mix at the National Skin Centre, Singapore. This is a retrospective review of 1256 patients who were patch tested to SL mix (0.1%) from January 1995 to December 1997. 18 out of 1256 patients (1.43%) reacted positively to SL mix. Their ages ranged from 13 to 58 years (average 33.8 years). There were 15 Chinese, 2 Indian and 1 Malay patients. There was a female preponderance, with a female: male ratio of 3.5:1. The most common clinical presentation were dermatitis of the hands (8; 44%), face (5; 28%), and generalized involvement (5; 28%). After extensive evaluation, only 2 patients had a positive patch test reaction that was of current clinical relevance. 13 patients had concomitant sensitization to other allergens. The 3 commonest concomitant allergens were nickel, balsam of Peru and fragrance mix. In our series, SL allergy is observed to be more common in females and the mean age is lower compared to the classical Compositae dermatitis. The sensitization rate is comparable to other studies, although the clinical relevance is only 11%.
The mechanisms of nitric oxide (NO)-mediated inhibition of vascular smooth muscle (VSM) cell proliferation are still obscure. Cyclins A and E in association with cyclin-dependent kinase 2 (cdk2) serve as positive regulators for mammalian cell cycle progression through the G1/S checkpoint of the cell cycle and subsequent cell proliferation. Therefore, we have tested the effect of adenovirus-mediated transfection of the endothelial nitric oxide synthase (eNOS) gene into guinea pig coronary VSM cells on platelet-derived growth factor (BB homodimer) (PDGF-BB)-stimulated cell proliferation and the expression of cell cycle regulatory molecules. Transfection of the eNOS gene (eNOS) into VSM cells significantly inhibited (P < 0.05) [3H]thymidine incorporation into the DNA in response to PDGF-BB stimulation compared with lacZ-transfected control cells. The eNOS transfer significantly inhibited (P < 0.05) PDGF-BB-induced proliferating cell nuclear antigen (PCNA) and cyclin A expression in VSM cells compared with cells transfected with the control vector. The time course of cyclin E expression in response to PDGF-BB stimulation was delayed in eNOS-transfected cells. Levels of cyclin-dependent kinase inhibitors p21 and p27 were not significantly affected by eNOS transfer. eNOS transfer did not decrease PDGF-beta receptor number, affinity, and autophosphorylation measured by radioreceptor assay and Western analysis. These results suggest that inhibition of PDGF-stimulated expression of cyclin A, cyclin E, and PCNA is the target of NO action. These findings could explain, at least in part, NO-mediated inhibition of VSM cell proliferation.
The zonal uptake of estrone sulfate (E1S; 1 to 400 microM) was investigated in periportal and perivenous rat hepatocytes and cells isolated from whole liver (regular hepatocytes). Transport of E1S by periportal, perivenous, and regular hepatocytes was described by saturable (Kms of 24 to 26 microM and Vmaxs of 1.8 nmol/min/mg protein) and nonsaturable components (2.5 to 3.2 microl/min/mg protein) that were not different among the zonal regions (p >.05, ANOVA). These kinetic constants represented pooled values for the entire complement of transporters for E1S, including two known transporters of E1S: Ntcp, Na+-taurocholate cotransporting polypeptide, and oatp1, the organic anion transporting polypeptide cloned from rat liver. Uptake of E1S was significantly reduced by estradiol 17beta-glucuronide (50 microM) and bumetanide (200 microM), and was inhibited strongly and competitively by pregnenolone sulfate with an inhibition constant of 6.7 microM. Further segregation of the kinetic constants as the sodium-dependent and -independent systems was achieved through simultaneous fitting of data obtained in the presence and absence of sodium from parallel hepatocytic uptake studies. For the periportal, perivenous, and regular hepatocytes, two saturable systems: a sodium-dependent transport system, characterized by similar Vmaxs (1.1 to 1.4 nmol/min/mg protein) and Kms (49 to 55 microM), a sodium-independent transport system of comparable Vmaxs (0.70 to 0.84 nmol/min/mg protein) and Kms (16 to 22 microM), and a linear clearance of 1.7 to 2.7 microl/min/mg protein (ANOVA, p >.05) were obtained. The data suggest that hepatic uptake of E1S involved sodium-dependent and -independent transporter systems. No heterogeneity in transport was observed.
Idiopathic hypereosinophilic syndrome (HES) is a disorder of the hematopoietic system, characterized by persistent elevation in the total eosinophil count (> 1500/microliter) for over 6 months, associated with organ damage and no detectable underlying cause. Treatment is centered on the reduction of total circulating eosinophils, which generally leads to remission of symptoms. We report a 68-year-old female patient with HES and peripheral neuropathy, presenting with cutaneous lesions, mental changes, cardiac and pulmonary symptoms, followed by right foot drop and eventually paraparesis, which caused an inability to ambulate. Weakness progressed to include the upper extremities despite adequate control of eosinophilia by steroids. Worsening of the peripheral neuropathy can occur despite lowering of the eosinophil levels.
We report a 58-year-old Chinese female who presented with a pigmented skin lesion on the right thigh, associated with a single ipsilateral inguinal lymph node without distant metastases detected. A wide excision of the tumour, split skin graft coverage and an en-bloc ipsilateral superficial groin dissection was performed. Histopathology revealed malignant skin adnexal tumour or porocarcinoma, with nodal metastases. She is presently at six months follow-up without any recurrence.
We assessed the impact of zonal factors on the hepatic reduced glutathione (GSH) conjugation of ethacrynic acid (EA). Uptake of EA by enriched periportal (PP) and perivenous (PV) rat hepatocytes was characterized by both saturable (V(max)(uptake) = 3.4 +/- 1.7 and 3. 2 +/- 0.8 nmol/min/mg protein and K(m)(uptake) = 51 +/- 13 and 44 +/- 15 microM) and nonsaturable (12 +/- 5 and 12 +/- 3 microl/min/mg protein) components. Values for the overall GSH conjugation rates of EA (200 microM) were similar among the zonal hepatocytes and resembled those for the influx transport rates. In the absence of the hepatocyte membrane, GSH conjugation in PV and PP hepatocyte cytosol was similar, but a higher perivenous GSH conjugation activity toward EA (PV/PP of 2.4) that mirrored the higher PV/PP ratios of immunodetectable GSTs Ya (1.7) and Yb2 (2.5) was found in cell lysates obtained by the dual-digitonin-pulse perfusion technique. The GSH conjugation rates in the subcellular fragments were, however, much greater than those observed for intact hepatocytes. Efflux rates of the glutathione conjugate EA-SG from zonal hepatocytes were similar, as were levels of the immunodetectable multidrug-resistance protein 2/canalicular multispecific organic anion transporter (Mrp2/cMoat) in the 100,000g pellets. The composite results suggest that the GSTs responsible for EA metabolism are more abundant in the PV region, albeit that the gradient of enzymatic activities is shallow. Despite the existence of zonal metabolic activity, the overall GSH conjugation rate of EA is homogeneous among cells because the reaction is rate limited by uptake, which occurs evenly. Results on EA-SG efflux suggest the acinar homogeneity in Mrp2/cMoat function for canalicular transport.
This retrospective study characterises the clinical manifestations and outcome of 34 patients diagnosed with Behcet's disease seen at the National Skin Centre from 1990 to 1997. The 2 diagnostic criteria used were the International Study Group and the O'Duffy criteria. Seventy-six per cent satisfied both criteria and the remaining 24% satisfied only the incomplete form of the O'Duffy criteria. We found that the male to female ratio was 1:1.8. The mean age of presentation was 33 years (range 21 to 63 years). The majority were Chinese (73%). In our series, patients had prominent mucocutaneous involvement. These findings may be attributed to patient selection to a tertiary dermatology clinic. Oral (100%) and genital (99%) ulceration were the 2 commonest symptoms. The other cutaneous features included papulo-pustular or acneiform eruption (26%), erythema nodosum (14.7%) and positive pathergy test. Five patients (15%) had arthritis, 1 patient had recurrent thrombophlebitis and 2 patients had eye complications. The outcome of our patients was generally good with minimal functional impairment and no mortality detected. Our patients were primarily outpatient referrals and this may explain why systemic complications were rare in our series.
The authors determined the cost-effectiveness of computed tomography (CT) of the inadequately visualized C7-T1 level on conventional radiography in a retrospective cohort study. Routine cervical spine radiography was performed in 360 trauma patients in whom the C7-T1 level was not adequately visualized, but there was no evidence of lower cervical spine injury. In these patients, CT of C7-T1 was performed and reviewed for the presence, location, and pattern of fracture. An orthopaedic surgeon was consulted regarding his proposed treatment and the presumed natural history without treatment of each C7-T1 injury identified. Based on Medicare reimbursement data, cost-effectiveness was then calculated for 1) each fracture identified, 2) each fracture that required surgical fixation secondary to risk of further neurologic sequelae (definitely unstable), and 3) each fracture that required either surgical fixation or halo immobilization secondary to the risk of development of cervical instability and arthritis (potentially or definitely unstable). Eleven of 360 fractures of C7-T1 were identified. The cost-effectiveness of CT for averting potential sequelae was $9,192 for each fracture identified, $16,852 identified for each potentially or definitely unstable fracture identified, and $50,557 for each definitely unstable fracture identified. Computed tomography of the inadequately visualized C7-T1 level on plain radiography is cost-effective, especially given the relatively young age of the trauma population and therefore the high associated morbidity of the sequelae of these injuries over time.
BACKGROUND: A strong association has been found between skin cancer and exposure to UV radiation. The p53 tumor suppressor gene (also known as TP53), which is frequently mutated in human cancers, is believed to be an early target in UV radiation-associated skin carcinogenesis. We have previously developed a sensitive, polymerase chain reaction-based method capable of detecting and quantifying a UV radiation-specific mutation in the p53 gene (codons 247 and 248: AAC CGG --> AAT TGG) in normal skin. We have used this method to examine whether UV radiation-specific mutation frequency is associated with risk of basal cell carcinoma (BCC) and with sun exposure. METHODS: This case-control study in Australia involved 53 case subjects with BCC and 75 control subjects. DNA was isolated from normal skin (mirror-image anatomic site to the cancer site for case subjects and a randomly selected site for control subjects) and assayed for p53 mutation. Relationships between p53 mutation frequency and risk of BCC, sun sensitivity, or sun exposure were estimated by use of odds ratios (ORs) and 95% confidence intervals (95% CIs). RESULTS: Case subjects were more likely to have a p53 mutation than control subjects (OR = 3.1; 95% CI = 1.3-7.1). In addition, the odds of BCC increased monotonically with increasing frequency of p53 mutation. No statistically significant associations could be demonstrated between p53 mutation frequency and age, sex, sensitivity to the sun, pigmentary characteristics, total lifetime sun exposure, or sun exposure to the biopsy site. CONCLUSIONS: Our results indicate that tandem CC --> TT mutations involving codons 247 and 248 of the p53 gene are associated with an increased risk of BCC but cannot be used as an accurate measure of total UV-radiation exposure.
Aeromonas hydrophila is a Gram-negative bacterium that is pathogenic in fish, causing motile aeromonad septicaemia. It can enter (invade) fish cells, and survive as an intracellular parasite. The host-pathogen interaction and signal transduction pathway were studied by screening signal transduction inhibitors using carp epithelial cells and a virulent strain of the bacterium, PPD134/91. Genistein, a tyrosine kinase inhibitor, postponed internalization of A. hydrophila into host cells, suggesting that tyrosine phosphorylation plays a role in internalization. In contrast, staurosporine, a protein kinase C inhibitor, and sodium orthovanadate, a protein tyrosine phosphatase inhibitor, accelerated internalization of PPD134/91. Other virulent strains of A. hydrophila were also examined and it is likely that all strains, irrespective of serogroup, use the same signalling pathway to facilitate bacterial uptake.
An 87-year-old female presented with a 3 month history of hyperkeratotic nodules on her left shin. An initial clinical and histological diagnosis of multiple squamous cell carcinomas on the left shin was made. Review of the biopsy, however, showed hypertrophic lichen planus with pseudoepitheliomatous hyperplasia. Typical lichen planus was seen affecting the oral mucosa, nails and skin elsewhere.
OBJECTIVE: To determine if the performance of the sperm penetration assay (SPA) is useful in predicting successful in vitro fertilization (IVF). METHODS: A meta-analysis was set up to determine the performance of SPA in the prediction of IVF success. We collected data on 647 patients in 24 studies. For each study, a two-by-two table was constructed from the results of SPA and IVF. RESULTS: The sensitivity and specificity of SPA as compared to IVF were heterogeneous. A summary receiver operating characteristics curve could be estimated, showing that the sensitivity of SPA was only 37%, with a specificity of 95%. Subgroup analysis did not explain the lack of homogeneity. CONCLUSION: Since withholding IVF inappropriately has major consequences, performing SPA is insufficient for selecting patients for treatment with IVF-embryo transfer.
Autosomal recessive limb girdle muscular dystrophy (LGMD2) is a clinically and genetically heterogenous group of diseases involving at least six different loci. Five genes have already been identified: calpain-3 at LGMD2A (15q15), and four members of the sarcoglycan (SG) complex, alpha-SG at LGMD2D (17q21), beta-SG at LGMD2E (4q12), gamma-SG at LGMD2C (13q12), and delta-SG at LGMD2F (5q33-q34). The gene product at LGMD2B (2p13-p16) is still unknown and at least one other gene is still unmapped. We investigated 20 Turkish families (18 consanguineous) diagnosed as having LGMD2. Most of our patients had onset of symptoms before age 10. The phenotypes varied from severe to benign. We analyzed the SG complex by immunofluorescence and/or western blot. Genotyping was performed using markers defining the six known loci and the suspected genes were screened for mutations. Six of 17 index cases showed deficiency of the SG complex, by immunofluorescence and/or western blot. Seven cases involved one of the known genes of the SG complex (alpha, 2; beta, 1; and gamma, 4 cases), and five mutations were documented in the alpha- and gamma-SG genes. After linkage analysis, 10 families were characterized as having LGMD2A (calpain-3 deficiency), and all mutations were eventually identified. One family was classified as having LGMD2B and 1 family that has normal SGs was linked to the chromosome 5q33-q34 locus (LGMD2F). In 1 family there was no linkage to any of the known LGMD2 loci. It appears that in Turkey, there is a broad spectrum of genes and defects involved in LGMD2. It may be possible to correlate genotype to phenotype in LGMD2. All severe cases belonged to the gamma-SG-deficiency group. Nine calpain-3-deficient cases had intermediate and 1 had moderate clinical courses. The LGMD2B patient had a moderate clinical expression, whereas the LGMD2F case was truly benign.
Merosin-deficient congenital muscular dystrophy (CMD) is an autosomal recessive condition usually with onset at birth or within the first months of life. Affected children are severely disabled and usually do not achieve the ability to walk without support. They invariably have white matter abnormalities on brain magnetic resonance imaging (MRI). We report a 29-year-old man with a late childhood onset limb-girdle type muscular dystrophy and cerebral white matter changes on MRI. Immunocyto-chemical studies of the patient's muscle biopsy showed a reduction in expression of the laminin alpha 2 chain of merosin. The patient had three affected siblings, and microsatellite genotyping confirmed linkage to the laminin alpha 2 locus (LAMA2) on chromosome 6q2 in this family. This case probably represents a milder allelic variant of classical merosin-deficient CMD. Merosin status should be assessed in patients with late-onset limb girdle muscular dystrophy.
OBJECTIVES: To determine the levels of two quinolones, ofloxacin and ciprofloxacin, potent broad-spectrum antibiotics with very good oral bioavailability and low minimum inhibitory concentrations (MICs) for most pathogens, in the prostates of patients who underwent transurethral resection of the prostate (TURP) after oral ingestion for surgical prophylaxis. PATIENTS AND METHODS: Twenty-eight patients with BPH requiring a TURP ingested 250 mg of both drugs 2-4 h before operation. The levels of the drugs in the serum and prostate were measured using high-performance liquid chromatography and the levels of both drugs determined at the 6 and 9 o'clock positions in the prostate to examine any local variations in drug concentration. RESULTS: Ofloxacin concentrations were significantly higher in the serum and prostatic tissues compared with ciprofloxacin for the same dose, but its penetrance into the prostate was lower. This mainly reflected its higher oral bioavailability. Both drugs were present in concentrations 50% higher at the 6 o'clock than at the 9 o'clock position but both exceeded the MICs for most Gram-negative organisms except Pseudomonas. CONCLUSION: Ofloxacin has the advantage against ciprofloxacin of exceeding the MICs for Staphylococcus and Chlamydia. However, ciprofloxacin has the advantage of having prostate-to-serum ratios of unity, but for the same dose the prostatic concentrations of ofloxacin is significantly higher.