The epidemiology of atopic dermatitis at a tertiary referral skin center in Singapore

Atopic dermatitis is a common chronic, relapsing, pruritic ecematous skin condition with a predilection for the flexural areas and occurs in patients with a personal or family history of atopy. The aim of this study is to describe the profile of atopic dermatitis seen at the National Skin Centre in Singapore. A retrospective chart review was conducted of all the patients with atopic dermatitis seen during the first six months of 1994. There were 492 patients whose ages ranged from one month to 74 years with an equal sex ratio. The prevalence was 2%. The onset of the disease occurred before the age of 10 years in 61.2% of patients. In 13.6% of the patients, the onset was after the age of 21 years. Two hundred and fifty-four patients (52%) had "pure" atopic dermatitis without concomitant respiratory allergies. Two hundred and thirty-eight patients (48%) suffered from a "mixed" type, with 23% having allergic rhinitis, 12% having asthma and 13% having both asthma and allergic rhinitis. Two hundred and thirty-one patients (47%) had at least one first-degree family member with atropy: atopic dermatitis (17%), asthma (15%) and allergic rhinitis (15%). Most of the patients, 416 (84.5%), had subacute eczema at presentation. Ichthyosis vulgaris was present in 38 patients (8%) and pityriasis alba in 13 patients (3%). The most common infective complication was bacterial infection (impetiginized eczema, folliculitis, cellullitis) present in 95 patients (19%) followed by viral infections (eczema herpeticum, viral warts and molluscum contagiosum) in 17 patients (3%). Allergies were noted in 43 patients (9%) based on the history given. The most common was drug allergies (penicillin and co-trimoxazole) in 28 patients followed by food allergies in 11 patients. Common aggravating factors reported include heat, sweating, stress, thick clothing and grass intolerance. Most patients could be controlled with a fairly simple regimen of moisturizers, topical steroids and antibiotics for acute flares. Short courses of systemic steroids were used in 78 patients (16%). Three patients were treated with phototherapy, Two on UVAB and one on PUVA. The pattern of atopic dermatitis in Singapore is similar to that reported in the Western literature except for a lower prevalence and a significant proportion of adult onset atopic dermatitis.     

Lymphocyte proliferative responses to chlamydial antigens in human chlamydial eye infections.

In order to study the relationship between cell-mediated immune responses to Chlamydia trachomatis and the pathogenesis of human chlamydial eye disease, we have measured the peripheral blood lymphocyte proliferative responses to whole chlamydial elementary bodies in 40 subjects with oculogenital chlamydial infection of varying severity, 13 subjects with genital chlamydial infections and 12 healthy seronegative controls. The mean stimulation index was significantly higher in those with oculogenital infections than in controls. There was a strong correlation between the response to C. trachomatis serotypes B and L1. We studied the relationship between proliferative responses and four clinical parameters: follicular conjunctivitis, papillary hypertrophy, corneal pannus and epithelial punctate keratitis, but were unable to show a significant association with any of these. Nor was there any association between proliferative response and serum antibody titre to C. trachomatis (pooled serotypes D-K), duration of disease or quantitative isolation of chlamydia from the conjunctiva. The depletion of CD8+ cells had no consistent effect on proliferative responses to serotype L1 in 13 subjects.     

Characterization of knitted polymeric scaffolds for potential use in ligament tissue engineering

Different scaffolds have been designed for ligament tissue engineering. Knitted scaffolds of poly-L-lactic acid (PLLA) yarns and co-polymeric yarns of PLLA and poly(glycolic acid) (PLGA) were characterized in the current study. The knitted scaffolds were immersed in medium for 20 weeks, before mass loss, molecular weight, pH value change in medium were tested; changes in mechanical properties were evaluated at different time points. Results showed that the knitted scaffolds had 44% porosity. There was no significant pH value change during degradation, while there was obvious mass loss at initial 4 week, as well as smooth molecular weight drop of PLLA. PLGA degraded more quickly, while PLLA kept its integrity for at least 20 weeks. Young's modulus increased while tensile strength and strain at break decreased with degradation time; however, all of them could maintain the basic requirements for ACL reconstruction. It showed that the knitted polymeric structures could serve as potential scaffolds for tissue-engineered ligaments.     

Disease-bearing insects brought in by international aircraft into Singapore

Fifty-seven (17.3%) of 330 incoming aircraft landing at Changi International Airport were found to harbour mosquitoes and other insects on board. The frequency of insects detected in aircraft from the Southeast Asian countries varied from 7.1% to 32.2%. Live insects were found in 5 (6.1%) of 82 aircraft disinsectized by the "block away" method. The species of mosquitoes brought in were: Culex quinquefasciatus (96), Culex tritaeniorhynchus (1), Aedes albopictus (2) and Aedes aegypti (1). None of the 51 female Culex quinquefasciatus dissected was found to be infected with microfilariae. They key to the prevention of introduction of exotic vectors and transmission of vector- borne diseases is to continue with the existing system of vector surveillance and control at the international airport, rather than routine disinsecting of aircraft landing in Singapore.     

A multi-center study on recurrent inguinal hernias: assessment of surgeons’ compliance to guideline-based repair and evaluation of short-term outcomes

Hernia - As patients with recurrent inguinal hernia (RIH) are at a higher risk of perioperative complications, international guidelines have been developed to mitigate these risks by recommending...     

Extracellular vesicles released from irradiated neonatal mouse cheek tissue increased cell survival after radiation

Alopecia is one of the common symptoms after high-dose radiation exposure. In our experiments, neonatal mice that received 7 Gy X-ray exhibited defects in overall hair growth, except for their cheeks. This phenomenon might suggest that some substances were secreted and prevented hair follicle loss in the infant tissues around their cheeks after radiation damage. In this study, we focused on exosome-like vesicles (ELV) secreted from cheek skin tissues and back skin tissues, as control, and examined their radiation protective effects on mouse fibroblast cell lines. We observed that ELV from irradiated cheek skin showed protective effects from radiation. Our results suggest that ELV from radiation-exposed cheek skin tissue is one of the secreted factors that prevent hair follicle loss after high-dose radiation.     

Tumour necrosis factor beta (lymphotoxin) inhibits locomotion and stimulates the respiratory burst and degranulation of neutrophils.

The data presented here demonstrate that recombinant human tumour necrosis factor beta (rHuTNF beta; lymphotoxin) is a neutrophil modulator. The lymphokine inhibited the locomotion of neutrophils and augmented the neutrophil oxygen-dependent respiratory burst in response to N-formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP) and phorbol myristate acetate (PMA), as measured by their capacity to produce chemiluminescence, H2O2 and superoxide. The effects on the respiratory burst occurred at a tenth of the concentration of TNF beta required to inhibit locomotion. After incubation with TNF beta, the neutrophils could be washed without any reduction in their capacity to show augmented responses. The TNF beta enhanced granule enzyme (lysozyme and beta-glucuronidase) release of neutrophils stimulated with cytochalasin B-FMLP.     

Prognostic-significance of chromosome 5q and 17p allelic deletion in colorectal adenocarcinomas

Patient survival was analysed for 75 patients after surgery for primary colorectal adenocarcinoma with regards to allelic loss of chromosome 17p and chromosome 5q. Allelic loss of chromosome 17p occurred in 69% of patients and was not significantly associated with a poorer patient prognosis as assessed by log rank analysis of Kaplan-Meier survival plots (p = 0.161). Allelic loss of chromosome 5q occurred in 32% of patients and was significantly associated with a poorer patient prognosis as assessed by log rank analysis of Kaplan-Meier survival plots (p = 0.014). Analysis of the two variables by Cox regression analysis indicated that allelic loss of chromosome 5q was an independent variable for patient prognosis. Entry of Dukes' stage into the model resulted in a final model with Dukes' stage and allelic loss of chromosome 5q as independent significant variables in assessing patient survival. These results show that allelic loss of chromosome 5q, but not chromosome 17p provides additional prognostic information for assessing patient survival, over and above Dukes' stage.