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T Y Chuang

Publications and source records attributed to T Y Chuang.

At least 19 recordsLinked to original sources
PubMed2006

Insulin sensitivity and resistin expression in nitric oxide-deficient rats.

AIMS/HYPOTHESIS: The aim of this study was to investigate changes in insulin sensitivity and expression of the gene encoding resistin (Retn) in adipocytes from long-term nitric oxide (NO)-deficient rats. METHODS: Male Sprague-Dawley rats received [Formula: see text]-nitro-L: -arginine methyl ester (L-NAME 0.5 mg/ml) in their drinking water for 4 weeks, while control rats received plain drinking water. During the experimental period, changes in plasma glucose, insulin and C-peptide levels were measured. After administration of L-NAME for 4 weeks, insulin sensitivity was evaluated in vivo and in vitro. An insulin binding assay was also performed to determine the number and binding affinity of insulin receptors in adipocytes. Adipocyte Retn mRNA levels were examined using northern blotting. RESULTS: Successful induction of NO deficiency was demonstrated by an increase in systemic blood pressure. No difference in plasma glucose levels was found between the two groups. Compared with the control rats, plasma insulin and C-peptide levels were significantly decreased in the NO-deficient rats, and insulin sensitivity was significantly increased. Insulin-stimulated glucose uptake and insulin binding capacity, but not binding affinity, were significantly increased in adipocytes isolated from NO-deficient rats. In addition, adipocyte Retn mRNA levels, but not plasma resistin levels, were significantly decreased in NO-deficient rats, and the Retn mRNA levels were negatively correlated with insulin sensitivity. CONCLUSIONS/INTERPRETATION: Insulin sensitivity was increased in NO-deficient rats and this was associated with insulin binding capacity and downregulated Retn expression. These findings suggest that NO plays a regulatory role in metabolism. Dysregulation of NO production may result in the development of metabolic disorders.

Adipocytes↗
PubMed2004

Temporal differences in relative phasing of gait initiation and first step length in patients with cervical and lumbosacral spinal cord injuries.

STUDY DESIGN: Comparison group design. OBJECTIVE: To compare the temporal distance factors during gait initiation between patients with incomplete cervical spinal cord injury, incomplete lumbosacral spinal lesion, and unimpaired control adults. SETTING: Human performance and movement analysis laboratory, Taiwan. PARTICIPANTS: Five patients with an incomplete cervical spinal cord injury (Group 1), five patients with an incomplete lumbosacral spinal lesion (Group 2) and nine unimpaired control adults (Group 3). METHODS: Subjects underwent a three-dimensional gait analysis. The total gait initiation period, reaction time, each relative phasing of gait initiation and the length of the first step were identified by using the kinematic measurement system. MAIN OUTCOME MEASURES: The total gait initiation period (start of the auditory cue for gait initiation to heel-strike of the first swing leg); each relative phasing of gait initiation indicated that the duration of the preparatory phase (start of auditory cue for gait initiation to heel-off of the first swing leg), the duration of the push-up phase (heel-off to toe-off of the first swing leg), and the duration of the single-stance phase (toe-off to heel-strike of the first swing leg) established by the total gait initiation period; and the length of the first step. RESULTS: The gait initiation period was greater in Groups 1 and 2 than that of Group 3 (P<0.05). Each relative phasing including the duration of the preparatory phase, the push-up phase, and the swing phase relative to the total gait initiation period, did not differ among Groups 1-3 (P>0.05). The length of the first step, measured while the nonpreferred leg stepped first in Groups 1 and 2, was shorter than that of Group 3 (P<0.05). CONCLUSIONS: Patients with incomplete cervical spinal cord injuries or lumbosacral spinal lesions took more time in gait initiation than unimpaired control adults. The first step length also reduced in these patients while the nonpreferred leg stepped first, as compared to unimpaired control adults. The data indicated that centrally programmed gait initiation might be preserved in ASIA-D spinal patients who, in this study, executed gait initiation with varying temporal distance strategies to compensate for peripheral impairments, as compared to unimpaired control adults.

Adult↗
PubMed2001

Neurourologic findings in patients with traumatic thoracolumbar vertebra junction lesions.

OBJECTIVE: To investigate neurourologic involvement in injuries to the thoracolumbar vertebra junction with magnetic resonance imaging (MRI) and electrophysiologic and urodynamic measurements and to characterize the neurogenic mechanisms of voiding dysfunctions. DESIGN: Baseline comparisons among 3 anatomic groups before neural repair. SETTING: Tertiary care center. PATIENTS: Thirty-five T11 to L2 spinal cord injury patients consecutively admitted to a rehabilitation unit. Eight patients (Group 1) had above-conus lesions without denervation and polyphasic waves revealed in the anal sphincter electromyography; 13 patients (Group 2) had conal and/or above-conus lesions and anal sphincter electromyographic abnormalities; and 14 patients (Group 3) had below-conus lesions and anal sphincter electromyographic abnormalities. MAIN OUTCOME MEASURES: Comparison of features identified on pudendal nerve terminal motor latency, urethral pressure profiles, and multichannel voiding pressure-flow study. RESULTS: The pudendal nerve terminal motor latency in Group 3, showing a significantly higher abnormal ratio (100%; p =.011, Fisher's exact test), indicated that cauda equina lesions might be the cause. Urodynamic data from Group 3 showed a significant decrease in maximal urethral closure pressure (48 +/- 17cm H2O, p =.0022, analysis of variance [ANOVA], repeated measure) and an increase in bladder capacity (429 +/- 194mL, p =.037, ANOVA, repeated measure). There were no significant changes in the other groups. CONCLUSION: Neurourologic abnormalities are less predictable with injuries to thoracolumbar junction, except in patients with cauda equina lesions.

Adult↗
PubMed2001

The specialty of the treating physician affects the likelihood of tumor-free resection margins for basal cell carcinoma: results from a multi-institutional retrospective study.

BACKGROUND: Basal cell carcinoma (BCC) is the most common cutaneous malignancy. Surgical experience and physician specialty may affect the outcome quality of surgical excision of BCC. METHODS: We performed a multicenter retrospective study of BCC excisions submitted to the respective Departments of Pathology at 4 major university medical centers. Our outcome measure was presence of histologic evidence of tumor present in surgical margins of excision specimens (incomplete excision). Clinician experience was defined as the number of excisions that a clinician performed during the study interval. The analytic sample pool included 1459 tumors that met all inclusion and exclusion criteria. Analyses included univariate and multivariate techniques involving the entire sample and separate subsample analyses that excluded 2 outlying dermatologists. RESULTS: Tumor was present at the surgical margins in 243 (16.6%) of 1459 specimens. A patient's sex, age, and tumor size were not significantly related to the presence of tumor in the surgical margin. Physician experience did not demonstrate a significant difference either in the entire sample (P <.09) or in the subsample analysis (P >.30). Tumors of the head and neck were more likely to be incompletely excised than truncal tumors in all the analyses (P <.03). Compared with dermatologists, otolaryngologists (P <.02) and plastic surgeons (P <.008) were more likely to incompletely excise tumors; however, subsample analysis for plastic surgeons found only a trend toward significance (P <.10). Dermatologists and general surgeons did not differ in the likelihood of performing an incomplete excision (P >.4). CONCLUSION: The physician specialty may affect the quality of care in the surgical management of BCC.

Aged↗
PubMed2001

Use of the Dermatology Life Quality Index (DLQI) in a midwestern US urban clinic.

BACKGROUND: The Dermatology Life Quality Index (DLQI), a self-administered general dermatology quality of life instrument, was originally developed and published in a dermatology clinic at University Hospital of Wales. OBJECTIVE: Our goal was to test the feasibility of having patients answer the DLQI in a busy dermatology clinic and to find out to what extent results vary from those published in Wales. We also wanted to examine the validity of the index in terms of the correlation between DLQI scores and stage of illness (disease severity). METHODS: We administered the DLQI to 200 consecutive patients who were seen in a dermatology clinic at Indiana University Medical Center. Results were examined in light of results found by those who originated the DLQI. A pilot group of patients were given the DLQI and rated for severity of disease by means of the Dermatology Index of Disease Severity (DIDS). RESULTS: Overall, the DLQI is easy to administer and can be completed within 3 minutes. The scores in our study were compatible with those previously reported by the DLQI originators. There was a "ceiling" effect in that 11% of the patients indicated no quality of life impairment on the DLQI rating. This index shows stratification with severity of disease. CONCLUSION: The DLQI is an easy and efficient instrument for assessing quality of life in dermatology patients. Patients needed minimal assistance with the form. Our results were similar to those of the DLQI originators, and this further shows reliability and validity of the DLQI. In addition, this study further supports the use of DLQI as a quality of life instrument suitable for use in international studies.

Adolescent↗
PubMed2000

Predicting sentinel and residual lymph node basin disease after sentinel lymph node biopsy for melanoma.

BACKGROUND: The selection of patients for sentinel lymph node biopsy (SNB) and selective lymphadenectomy for histologically positive sentinel lymph nodes (SLND) are areas of debate. The authors of the current study attempted to identify predictors of metastases to the sentinel and residual nonsentinel lymph nodes in patients with melanoma. METHODS: The Indiana University Interdisciplinary Melanoma Program computerized database was queried to identify all patients who underwent SNB for clinically localized cutaneous melanoma. Demographic, surgical, and histopathologic data were recorded. Univariate and multivariate logistic regression analyses were performed to identify associations with SNB and nonsentinel lymph node positivity. Classification tree and logistic procedures were performed to identify the ideal tumor thickness cutpoint at which to perform SNB. RESULTS: Two hundred seventy-five SNB procedures were performed to stage 348 regional lymph node basins for occult metastases from melanoma. Of the 275 melanomas, 54 (19.6%) had a positive SNB, as did 58 of 348 basins (16.7%). Classification and logistic regression analysis identified a Breslow depth of 1.25 mm to be the most significant cutpoint for SNB positivity (odds ratio 8. 8:1; P = 0.0001). By multivariate analyses, a Breslow thickness cutpoint >/= 1.25 mm (P = 0.0002), ulceration (P = 0.005), and high mitotic index (> 5 mitoses/high-power field; P = 0.04) were significant predictors of SNB results. SLND was performed in 53 SNB positive patients, 15 of whom (28.3%) had at least 1 additional positive lymph node. SLND positivity was noted across a wide range of primary tumor characteristics and was associated significantly with multiple positive SN, but not with any other variable. SNB result correlated significantly with disease free and overall survival. CONCLUSIONS: Patients with a Breslow tumor thickness >/= 1. 25 mm, ulceration, and high mitotic index are most likely to have positive SNB results. SLND is recommended for all patients after positive SNB because it is difficult to identify patients with residual lymph node disease.

Adolescent↗
PubMed2000

Ipsilateral hip and distal femoral fractures.

We tried to find the trauma mechanism and treatment rationale of ipsilateral concomitant hip and distal femoral fractures involving the articular surface. Between 1988 and 1995, 15 cases of ipsilateral hip (confined to neck or trochanteric areas of the femur) and distal (confined to supra- and intercondylar area of the femur) femoral articular fractures were collected. The hip fractures consisted of 10 trochanteric fractures and five neck fractures, which were managed with reduction and fixation in 14 (Knowles' pin in eight, DHS in four and standard Gamma nail in two), and primary bipolar hemiarthroplastry in one. The distal femoral articular fractures were open in 11; these were managed with radical debridement, implantation of Septopal chains and immediate internal fixation, followed by prophylactic autogenous bone grafting 6 weeks later in the recent six cases (five Judet plates, four dynamic condylar screws and two condylar plates). The other four closed distal femoral fractures were managed with early reduction and internal fixation (two Judet plate, one dynamic condylar screw and one condylar plate). The union time was 20.3 (12-48) weeks for proximal fractures and 23.7 (12-36) weeks for distal fractures. Early infection developed in three cases. Nonunion of a femoral neck fracture developed in one case. The other complications were implant failure in one, coxa vara in one, refracture in one, delayed union in one and knee stiffness in one.

Adult↗
PubMed2000

Current therapy of cutaneous melanoma.

Melanoma is a growing public health problem. Optimal care of the melanoma patient is multidisciplinary, but plastic surgeons and other surgical specialties play a central role in the management of these patients. Although surgery remains the mainstay of therapy for melanoma, several recent clinical studies have helped to clarify the biology of the disease and have changed the patterns of care for patients with melanoma. The advent of lymphatic mapping for interrogation of regional lymph nodes and interferon as the first effective postsurgical adjuvant therapy have had a major impact on the care of melanoma in the United States and elsewhere. This article will review the current clinical approach and therapy for cutaneous melanoma. The diagnosis, prognostic variables, staging evaluation, current surgical and medical treatment, and follow-up guidelines for patients with all stages of melanoma are reviewed. Recent studies, controversies, and directions of future investigational therapies will be discussed.

Combined Modality Therapy↗
PubMed2000

Sudomotor abnormalities in reflex sympathetic dystrophy.

BACKGROUND: Intractable pain and sweating dysfunction can occur in patients with reflex sympathetic dystrophy (RSD). We, therefore, investigated autonomic function by measuring sympathetic skin response (SSR) in these patients. This method provides useful information regarding the pathophysiologic changes in and clinical evaluation of RSD. METHODS: Twenty-six RSD patients and 22 age-matched normal subjects were involved in our investigation. Three significant stages of RSD were classified through three-phase bone scanning of the wrist, carpal and metacarpal bones. There were 11 patients in stage I RSD, nine in stage II and six in stage III. SSRs were recorded from the bilateral palms of each subject simultaneously using electrical stimulation of the median nerve in the wrist. Latency and amplitude side ratios were calculated and compared with the control group. RESULTS: The affected/normal (A/N) hand amplitude ratios were significantly lower in stage I RSD, and stage II RSD patients exhibited significantly higher A/N amplitude ratios compared with the control group. A/N amplitude and A/N latency ratios in stage III RSD did not change significantly. The A/N latency ratios in stage I RSD were significantly higher than those of the control group and those of stage II RSD. In one stage I patient and three stage III patients, SSRs were bilaterally unobtainable. CONCLUSIONS: It appears that abnormal SSRs may be associated with autonomic disturbance in RSD patients.

Adult↗
PubMed2000

Lobular capillary hemangiomas: An epidemiologic report, with emphasis on cutaneous lesions.

BACKGROUND: Lobular capillary hemangiomas (pyogenic granulomas) occur on both mucosal and cutaneous surfaces. There are conflicting data regarding the increased prevalence of lobular capillary hemangiomas in female versus male subjects. Some studies have noted a female predominance of lobular capillary hemangiomas, but other studies do not reveal such a disparity. Because of an increased prevalence during pregnancy, oral tumors are also known as "granuloma gravidarum" or "pregnancy tumors." A hormonal influence for these mucosal lesions has been postulated. There are, however, no studies that address a possible relationship between hormones and cutaneous lesions. OBJECTIVE: This study presents the epidemiology of lobular capillary hemangiomas, with an emphasis on cutaneous lesions. METHODS: We reviewed 63,759 dermatopathology reports from a regional, private dermatopathology laboratory and found 325 cases of lobular capillary hemangiomas over a 1-year period. RESULTS: In our study of lobular capillary hemangiomas, cutaneous lesions accounted for 86%, with mucosal lesions representing only 12% of cases. Seven cases were excluded (one was intravascular, two were subcutaneous, and in 4 the location was not specified). Overall, male patients outnumbered female patients. The peak incidence for cutaneous lobular capillary hemangiomas was found in the second decade of life. The most common cutaneous sites were the trunk, upper extremities, and head. Mucosal lesions were primarily seen on the lips, gingiva, and tongue, and these affected females more than males by a ratio of 2:1, most commonly in the fourth decade of life. CONCLUSION: Cutaneous lobular capillary hemangiomas were equally prevalent in male and female patients. This would refute a female hormonal influence in the induction of cutaneous lobular capillary hemangiomas. Our data may suggest a hormonal influence on mucosal lesions because mucosal lobular capillary hemangiomas were twice as common in female patients. However, the small number of lesions in our study precludes us from making such a conclusion.

Adolescent↗
PubMed2000

Treatment of acetabular fractures: 10-year experience.

BACKGROUND: Acetabular fracture is a controversial and difficult fracture to manage. We retrospectively evaluated the outcome of the traditional management of acetabular fractures. METHODS: From 1987 to 1996, 112 cases of acetabular fracture presented at the Taipei Veterans General Hospital and were managed surgically in 73 cases and nonsurgically in 39 cases. The follow-up period was 90 (36-140) months. RESULTS: In the nonsurgically managed group, congruent reduction was achieved in 29 cases (74.3%) and good to excellent functional results were achieved in 25 cases (64.1%). In the surgically managed group, congruent reduction was achieved in 60 cases (82.2%) and good to excellent functional results were achieved in 57 cases (74.3%). In 51 (45.5%) cases, early or late complications developed after management, including one femoral artery perforation, one screw penetration, three wound infections, one iatrogenic sciatic nerve injury, one deep vein thrombosis, 21 heterotopic ossifications, two chondrolyses, three avascular necroses of the femoral head and 18 cases of symptomatic traumatic arthritis. CONCLUSIONS: The functional results correlated well with the final congruity of the joints and the severity of the complications.

Acetabulum↗
PubMed1999

Hepatitis C virus and lichen planus: A case-control study of 340 patients.

Lichen planus (LP) has been associated with liver disease, particularly hepatitis C virus (HCV) infection, in several studies to date. Most of these reports, especially the larger series, were conducted in Europe. In addition, the type of LP associated with HCV was reported to be oral LP in most studies. We conducted a case-control study in a US metropolitan population known to have a low seroprevalence of HCV infection to explore the impact of geography and endemicity of HCV on the association between cutaneous LP and HCV. The study comprised 340 patients with cutaneous LP (as case ) against 577 patients with psoriasis (as control-1 ). Hepatitis antibody titers and liver function abnormalities were our main outcome measures. Prevalence of HCV antibody among 149,756 regional volunteer blood donors (as control-2 ) was also used for comparison. Twelve (55%) of 22 patients with LP tested for HCV were antibody positive. This was significantly higher than 25% of 40 psoriasis patients tested for HCV antibody (P =.04) or than 0.17% of blood donors tested for HCV antibody (P < 10(-5)). Thus a small but significant percentage of US patients with cutaneous LP had HCV antibody. Because LP may be the first presentation of HCV infection, it is important for clinicians to actively look for such infection in patients with LP.

Case-Control Studies↗
PubMed1999

Porphyria cutanea tarda and hepatitis C virus: a case-control study and meta-analysis of the literature.

BACKGROUND: Porphyria cutanea tarda (PCT) and hepatitis C virus (HCV) infection have been associated in several reports with the prevalence of HCV exhibiting considerable regional variation. However, most reports were confounded by selection bias and a regional prevalence of HCV in the populations studied. In the United States, only a few cases of this association have been reported to date. OBJECTIVE: We concluded a study to evaluate the association between PCT and HCV in a US population. We used a case-control study design to control the systemic error that may occur during a selecting process or sampling procedure. METHODS: We reviewed the medical records of Wishard Memorial Hospital, a county hospital serving metropolitan Indianapolis, Indiana, to perform a retrospective case-control study of 26 patients with PCT (as case) against 149,756 regional volunteer blood donors (as control-1) and 51 patients receiving methotrexate for psoriasis (as control-2). HCV antibody titers and other liver abnormalities were our main outcome measures. We then performed a weighted meta-analysis of 17 reports that had at least 17 patients in their study populations. RESULTS: Sixteen (94%) of 17 PCT patients tested for HCV were antibody positive. Among blood donors, only 255 or 0.17% were HCV antibody positive (P < 10(-5), two-sided chi-square test). Of 5 psoriasis patients tested for HCV, none were HCV antibody positive (P = .0002, two-sided Fisher's exact test). For geographic comparison, meta-analysis of the literature demonstrated a varying regional prevalence of HCV in PCT patients as follows: Northern Europe 17%, Australia/New Zealand 20%, and Southern Europe 65%. CONCLUSION: Although a marked geographic variation was found in the worldwide prevalence of HCV in PCT patients, a very large percentage of US patients with PCT had HCV infection. Our results emphasize the need for clinicians to actively look for HCV in patients with PCT.

Australia↗
PubMed1999

The diagnostic yield in submitting nevi for histologic examination.

BACKGROUND: Dermatologists have expertise in the clinical diagnosis of benign melanocytic nevi. However, there are no data to confirm the accuracy of diagnosis. Differences in the diagnostic accuracy between dermatologists and nondermatologists with regard to cutaneous tumors has been infrequently studied. OBJECTIVE: We examined the rate of malignant tumors occurring in lesions submitted for routine microscopic examination that were clinically diagnosed as benign melanocytic nevi. METHODS: We conducted a study at a regional, non-hospital-based dermatopathology laboratory using specimens submitted by physicians of various specialties who were practicing in a 5-state Midwest region of the United States. The preoperative and postoperative diagnoses were examined on the basis of information provided by the clinician and of the subsequent histopathologic diagnosis. A total of 7734 cutaneous pathology reports were reviewed. Specimens submitted with a preoperative clinical diagnosis of mole or nevus, with or without a modifier, were examined and compared with postoperative microscopic diagnoses. RESULTS: Of 1946 specimens clinically diagnosed and submitted as benign nevi, 45 (2.3%) were histologically diagnosed as malignant tumors. This included 12 melanomas, 30 basal cell carcinomas, and 3 squamous cell carcinomas. For specimens submitted by dermatologists, the rate of malignant tumors increased when clinical information suggested findings beyond the classic benign clinical presentation with the addition of modifiers such as irritated or atypical, or if a malignancy was considered in the differential diagnosis (trend for increasing clinical suspicion: P = .00002). Fewer dermatologists than nondermatologists mistook a malignant tumor for a benign nevus (1.3% vs 3.8%, P = .003). CONCLUSION: Our data document that 2.3% of clinically diagnosed benign nevi were microscopically diagnosed as malignant tumors. Whether this malignancy rate in clinically diagnosed, benign, melanocytic nevi is above or below the threshold to establish a policy for submission for histopathologic examination remains to be determined as a collective societal and medical professional responsibility.

Biopsy↗