PubMed Health⌕ Search

Biomedical subjects

T C Lim

Publications and source records attributed to T C Lim.

At least 19 recordsLinked to original sources
PubMed2006

A comparative analysis of scaffold material modifications for load-bearing applications in bone tissue engineering.

To facilitate optimal application of appropriate scaffold architectures for clinical trials, there is a need to compare different scaffold modifications under similar experimental conditions. In this study was assessed the effectiveness of poly-e-caprolactone (PCL) scaffolds fabricated by fused deposition modelling (FDM), with varying material modifications, for the purposes of bone tissue engineering. The incorporation of hydroxyapatite (HA) in PCL scaffolds, as well as precalcification through immersion in a simulated body fluid (SBF) to produce a biomimetic apatite coating on the scaffolds, was assessed. A series of in vitro studies spanning 3 weeks as well as in vivo studies utilizing a subcutaneous nude mouse model were carried out. PCL and HA-PCL scaffolds demonstrated increasing tissue growth extending throughout the implants, as well as superior mechanical strength and mineralization, as evidenced by X-ray imaging after 14 weeks in vivo. No significant difference was found between PCL and HA-PCL scaffolds. Precalcification with SBF did not result in increased osteoconductivity and cell proliferation as previously reported. Conversely, tensile forces exerted by tissue sheets bridging adjacent struts of the PCL scaffold caused flaking of the apatite coating that resulted in impaired cell attachment, growth and mineralization. The results suggest that scaffolds fabricated by FDM may have load-bearing applications.

Animals↗
PubMed2004

Changes in the local morphology of the rectus abdominis muscle following the DIEP flap: an ultrasonographic study.

This study was undertaken to assess the changes in the local morphology of the rectus abdominis muscle following intramuscular dissection of the deep inferior epigastric artery perforators after harvesting of the deep inferior epigastric perforator (DIEP) flap. While the DIEP provides the well-known advantage of use of the lower abdominal tissue with preservation of the integrity of the abdominal wall musculature, postoperative problems such as abdominal asymmetry, bulges and reduced flexion capacity have been found. These changes may be due to rectus abdominis muscle damage from ischemia or denervation. We used ultrasonography to assess the changes in rectus abdominis muscle thickness and contractility, preoperatively, 1-month and 1-year postoperatively. The study group consisted of 17 rectus abdominis muscles in 14 patients subjected to intramuscular dissection of perforators. The control group consisted of 11 intact rectus abdominis muscles in 11 patients who had undergone unilateral DIEP flap elevation, the dissected muscles being part of the study group. We found that the resting muscle thickness in the study group was, significantly increased at 1-month postoperatively, resolving by 1-year follow-up. As these changes were not seen in the control group, the increased muscle thickness is attributed to postoperative oedema that resolves with time. All muscles in the study and control groups retained contractility showing no evidence of muscle denervation. Our date demonstrates that intramuscular dissection of perforator vessels in the DIEP flap leads to minimal changes in the local morphology and contractility of the rectus abdominis muscle.

Adult↗
PubMed2004

The superior gluteal artery perforator flap for the closure of sacral sores.

The purpose of this paper is to report the use of the superior gluteal artery perforator (SGAP) flap in the closure of sacral pressure sores here in Singapore. This fasciocutaneous flap is a refinement of the musculocutaneous flap which is popularly used for the closure of sacral sores. There were minimal complications. This is a reliable flap and gives the option of further reconstructive possibilities should a recurrence occur.

Adult↗
PubMed2004

A case of ductal carcinoma in situ of breast with Poland syndrome.

INTRODUCTION: A 51-year-old woman was diagnosed with a rare case of multi-focal ductal carcinoma in situ (DCIS) of the breast associated with Poland syndrome. CLINICAL PICTURE: Physical examination showed mild hypoplasia of the left breast with microcalcifications on mammogram. Intraoperatively, there was complete absence of the pectoralis major, which precluded the insertion of a breast implant. TREATMENT AND OUTCOME: She underwent a skin-sparing mastectomy and autologous microsurgical free flap reconstruction with deep inferior epigastric perforator (DIEP) flap. Postoperative recovery was uneventful with no evidence of recurrence at 6 months. CONCLUSION: This is the first reported case of DCIS of the breast with Poland syndrome. We performed a skin-sparing mastectomy with immediate DIEP flap recontruction. Patient recovered well postoperatively with no evidence of recurrence at 6 months.

Breast Neoplasms↗
PubMed2002

Gabapentin for neuropathic pain following spinal cord injury.

STUDY DESIGN: Retrospective review of patient data. OBJECTIVE: To present two years of experience in the use of gabapentin for the alleviation of neuropathic pain in spinal cord injury patients. SETTING: Supra-regional Spinal Cord Service, Melbourne, Australia. METHOD: Data were retrieved from the medical records of all spinal cord injury patients prescribed gabapentin for neuropathic pain. Pain was assessed prior to and during treatment at 1, 3 and 6 months with a 10 cm visual analogue scale which ranged from 0 ('no pain') to 10 ('worst pain imaginable'), or by the documentation of a verbal description of pain. RESULTS: Seventy-six per cent of patients receiving gabapentin reported a reduction in neuropathic pain. In those patients with data at all four measurement points, the mean pretreatment score was 8.86. Following treatment with gabapentin the score dropped to 5.23, 4.59 and 4.13 at 1, 3 and 6 months, respectively. Where only a verbal description of pain was documented, the trend was that the pretreatment report of 'unbearable' was replaced by 'liveable' during treatment. CONCLUSION: Our experience suggests that gabapentin offers an effective therapeutic alternative for the alleviation of neuropathic pain following spinal cord injury. Controlled clinical trials are now required to confirm these observations.

Acetates↗
PubMed2001

Evaluation of ultra-thin poly(epsilon-caprolactone) films for tissue-engineered skin.

Various natural and synthetic polymeric materials have been used as scaffold matrices for tissue-engineered skin. However, the commercially available skin replacement products pose problems of poor mechanical properties and immunological rejection. We have thus developed a film of 5 microm thickness, via biaxial stretching of poly(epsilon-caprolactone) (PCL), as a potential matrix for living skin replacements. The aim of this study was to evaluate the feasibility of using biaxially stretched PCL films as matrices for culturing human dermal fibroblasts. For this purpose, we cultured human dermal fibroblasts for 7 days on the films. Glass cover slips and polyurethane (PU) sheets were used as controls. The data from phase contrast light, confocal laser, and scanning electron microscopy suggested that biaxially stretched PCL films support the attachment and proliferation of human dermal fibroblasts. Thymidine-labeling results showed quantitatively that cell proliferation on the PCL films was superior to that on the PU samples. These results indicated that biaxially stretched PCL films supported the growth of human dermal fibroblasts and might have potential to be applied in tissue engineering a dermal equivalent or skin graft.

Bioprosthesis↗
PubMed2001

The role of DRE in the diagnosis of prostate carcinoma.

DRE has been used as a diagnostic and screening tool for prostate cancer for decades. However these are based on Western data and its local applicability has yet to be verified. We held a Prostate Health Awareness Week in August 1998 and a total of 2086 men were screened. All men aged 50 years old and above were included for the study. The subjects were evaluated on DRE findings, PSA levels and if indicated a TRUS-guided biopsy results. We concluded that DRE per se might have limited role in the screening of prostate cancer in Malaysia. Screening using DRE and PSA combined are still recognized as the most cost-effective means. Neither DRE nor PSA alone has high enough specificity for diagnosis of prostate cancer cases. Combining DRE and PSA will definitely increase the specificity significantly.

Aged↗
PubMed2001

Prevalence of symptomatic BPE among Malaysian men aged 50 and above attending screening during prostate health awareness campaign.

OBJECTIVE: To study the prevalence of symptomatic BPE among Malaysian men age 50 and above attending prostate health awareness campaign and to identify differences in prevalence between different ethnic groups residing within metropolitan Kuala Lumpur. MATERIALS AND METHODS: Demographic data and the completed International Prostate Symptom Score (IPSS), maximal uroflow rate (Qmax) and prostate size of volunteers, aged 50 and above, who attended the prostate health awareness campaign were analyzed. Subjects with known prostate diseases or prostate surgery, bladder disorders and neurological disorders were excluded. RESULTS: 2086 volunteers attended the campaign. 575 men fulfilled the inclusion criteria and their demographic data, IPSS; peak flow rate and prostate volume were analysed. Overall, 18.9% and 39.6% of the men were severely and moderately symptomatic, respectively. The prevalence of moderate to severe lower urinary tract symptoms (LUTS) in Malays, Chinese and Indians were 70%, 59% and 50% respectively (p = 0.004). The commonest bothersome symptoms were nocturia (56%), frequency (50.4%) and sense of incomplete voiding (43.5%). The mean peak flow rate of the subjects was 15.4 ml/s. 20.9% and 55.2% of the subjects had peak flow less than 10 ml/sec and 15 ml/sec respectively. The mean prostate size was 25.1 cc. There is no significant difference in term of maximal flow rate and prostate size among Malays, Chinese and Indians in Malaysia. A good correlation was found between the total symptom score and the single disease-specific quality of life question (r = 0.69, p < 0.001). The correlation between IPSS and peak flow rate (r = -0.22, p < 0.001) and prostate volume (r = 0.11, p = 0.009) was weak. There was no correlation between IPSS and age (r = 0.06, p = 0.17). The prevalence of symptomatic benign prostate enlargement (BPE) was 39.3%. The prevalence increased 8% per decade from 41.7% for men aged 50 to 59 to 65.4% for men aged 70 or more. There is no significant difference in prevalence of symptomatic BPE among the three ethnic groups. The Prevalence of BPO was 15.8%. CONCLUSION: The correlation between symptom score, maximal flow rate and prostate size was poor and one cannot predict the value of one parameter by knowing one or more of the other parameters. There is a high prevalence of LUTS suggestive of benign prostatic obstruction in the apparently healthy Malaysian aged 50 and above attending the prostate health awareness campaign.

Age Factors↗
PubMed2000

Necrospermia and chronic spinal cord injury.

OBJECTIVE: To determine whether improvement in quality of semen over 4 consecutive days of electroejaculation in men with chronic spinal cord injury (SCI) was consistent with epididymal necrospermia. DESIGN: Prospective study of a random sample of men with SCI. SETTING: A southeastern Australian SCI management center in collaboration with the specialist andrology service of a university-based department of obstetrics and gynecology in a tertiary referral hospital. PATIENT(S): Nine men with chronic spinal cord injury. INTERVENTION(S): Semen samples were obtained by using electroejaculation, and testicular biopsy samples were obtained by using fine-needle tissue aspiration. MAIN OUTCOME MEASURE(S): Semen analysis was performed according to World Health Organization criteria. Testicular biopsy and electron microscopy were done by using standard techniques. RESULT(S): During up to 4 days of consecutive-day electroejaculation, sperm motility and viability in semen obtained from men with chronic SCI increased by an average of 23% on days 2 and 3. The severity of the degenerative changes and the numbers of spermatozoa affected on day 1 became less marked by day 4. The changes were not present in late spermatids obtained from testicular biopsies. CONCLUSION(S): The asthenospermia of chronic SCI is similar to epididymal necrospermia and can be improved by consecutive-day electroejaculation.

Adult↗
PubMed2000

Ophthalmic involvement in cranio-facial trauma.

OBJECTIVES: This is a retrospective descriptive case study which will look into the spectrum of ophthalmic involvement in cases with orbital and eye injuries after cranio-facial trauma and to analyse the visual and motility outcome. MATERIAL: One hundred and four cases with ophthalmic involvement after cranio-facial trauma that were referred to and seen in the eye department of a tertiary teaching hospital in Singapore between 1991-97 were included in the study. METHODS: The case records of 104 such patients were traced. The demographic data, the mode of injury, the type of fracture sustained and presence of serious eye injury were noted. The details about visual acuity, significant diplopia and enophthalmos at the first and last visits were charted. Presence of traumatic optic neuropathy including the type of treatment given was recorded. RESULTS: There was a male preponderance (82%). The industrial accidents were 21%, only next to road traffic accidents, which constituted approximately 36.5%. The predominant types of fractures seen were blow-out orbital fractures, complex fractures comprising of Le-Fort II, III, panfacial and fronto-basilar skull fractures. Diplopia was the most common presenting feature (40%) with visual acuity disturbance (23% having <6/60) as the next most common finding. Traumatic optic neuropathy was seen in 20% of patients and serious eye injury was present in 9% of patients. The incidence of traumatic optic neuropathy was significantly higher (p<0.001) in patients with complex fractures and fronto-basilar fractures, as compared to the blow-out and zygomatico-maxillary fractures. Analysis of final results indicated 15% as having significant diplopia in one or more gazes and 12.5% as having a vision of <6/60. CONCLUSION: Diplopia and visual acuity disturbances seem to be the most common ophthalmic presentations in cranio-facial trauma. A significant number of patients suffer from poor vision and significant diplopia despite treatment.

Accidents, Occupational↗