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Biomedical subjects

R S Yang

Publications and source records attributed to R S Yang.

At least 37 records · Page 2Linked to original sources
PubMed2000

Theoretical study of convergent ultrasound hyperthermia for treating bone tumors.

This study investigates the optimal external parameters for using an ultrasound applicator for treating bone tumors. This system utilized spherically arranged applicators such as scanned focused ultrasound, and spherically focused multielement applicators. The power deposition pattern is modeled as geometric gain with exponential attenuation. The specific absorption rate ratio (SARR) criteria have been used to determine the proper heating domain of ultrasound driving frequency and therapeutic tumor diameter. The results demonstrate that the optimal driving frequency depends on tumor depth, ultrasound absorption of bone marrow, and diameter of bone, but it is independent of the acoustic window area and SARR. The treatable diameter of bone tumor increased when the absorption ratio of bone marrow to tumor, acoustic window of surface skin, and diameter of bone were elevated. However, the treatable diameter of bone tumor decreased when muscle thickness, SARR of bone tumor site to the surface skin, bone marrow, and bone declined. To deliver the ultrasound energy into the tumor site and to avoid the potential damage to the normal tissue as much as possible, the specific absorption rate (SAR) in the bone tumor site has to be three times higher than that in the surface skin, tumor/marrow, and marrow/bone interfaces. The temperature distributions can verify the SARR criteria in this model. This study provides the information for choosing the optimal operating frequency of the ultrasound transducer and the acoustic window on the skin surface, and for designing the ultrasound applicator for clinical implementation.

Biomedical Engineering↗
PubMed2000

Comparative hepatocarcinogenicity of hexachlorobenzene, pentachlorobenzene, 1,2,4,5-tetrachlorobenzene, and 1,4-dichlorobenzene: application of a medium-term liver focus bioassay and molecular and cellular indices.

Of the twelve different chlorobenzene isomers, a thorough evaluation of carcinogenicity has only been assessed on monochlorobenzene, 1,2-, and 1,4-dichlorobenzene, and hexachlorobenzene. In the studies presented here, we measured the ability of 1,4-dichlorobenzene (DCB), 1,2,4,5-tetrachlorobenzene (TeCB), pentachlorobenzene (PeCB), and hexachlorobenzene (HCB) to promote glutathione S-transferase pi (GSTP1-1) positive preneoplastic foci formation in rat liver, following diethylnitrosamine (DEN) initiation. The results from these studies show that TeCB, PeCB, and HCB all promote the formation of GSTP1-1 positive foci and that DCB does not. The numbers and area of foci were greatest following HCB promotion, and TeCB and PeCB were approximately equal in their promoting ability. Levels of hepatic CYP1A2, CYP2B1/2, non-focal GSTP1-1, and c-fos were measured in response to treatment with the 4 chlorobenzene isomers, as were reduced glutathione (GSH) and oxidized glutathione (GSSG) levels. Results from these studies show that induction of CYP1A2 and CYP2B1/2 have correlation with both the presence and degree of GSTP1-1 foci promotion by the 4 chlorobenzenes. Alterations in GSH and GSSG levels were similar in PeCB- and TeCB-treated animals in that GSSG levels were significantly decreased, whereas HCB and DCB did not have this effect, although HCB treatment led to a significant increase in GSH levels. We conclude that induction of CYP1A2 or CYP2B1/2 by chlorobenzene isomers may indicate promotional ability, and that this property might be exploited to predict the hepatocarcinogenicity of other chlorobenzene isomers.

Animals↗
PubMed2000

Expandable endoprosthesis reconstruction in skeletally immature patients with tumors.

Between September 1984 and January 1996, 32 expandable endoprostheses were used for limb reconstruction after resection of malignant bone tumors in patients who were skeletally immature. The 20 boys and 12 girls ranged in age from 3 to 15 years (mean, 9.7 years). One patient had a Stage IIA tumor, 22 patients had Stage IIB tumors, and seven patients had Stage III tumors according to the classification of the Musculoskeletal Tumor Society. There also were two patients with parosteal osteosarcomas. The histologic diagnosis was osteosarcoma in 23 patients and Ewing's sarcoma in nine. All patients except the patients with parosteal osteosarcoma received standard neoadjuvant therapy. Twenty-two Lewis Expandable Adjustable Prostheses, four modular Wright Medical prostheses, four modular Howmedica prostheses, and two Techmedica expandable prostheses were used. Thirteen patients died, two have no evidence of disease, and 17 are continuously disease free. Sixteen of 32 patients (50%) have not had an expansion procedure because of early death in 10 and early amputation in three. Three patients are waiting to undergo an expansion procedure. Sixteen of the 32 patients (50%) have undergone 32 expansion procedures, to a maximum of 9 cm, without any infection. To maintain range of motion before the expansion procedure, a complete resection of the pseudocapsule was done routinely. Fourteen of the 32 patients did not have complications. Eighteen of the 32 patients had 27 complications. All Lewis Expandable Adjustable Prosthesis endoprostheses and the two nonmodular Techmedica prostheses were associated with a large amount of titanium debris. The children's functional results were similar to the results reported for adults with an average Musculoskeletal Tumor Society rating of good to excellent at the knee, fair to good at the hip, and fair about the shoulder. Rehabilitation of the knee in very young patients (5-8 years) remains problematic and careful selection of patient and family is necessary. The Lewis Expandable Adjustable Prosthesis probably should be reserved for very young patients (5-8 years) and modular systems should be used for large preadolescent and adolescent children.

Adolescent↗
PubMed2000

The role of 67Ga in the early detection of spinal epidural abscesses.

In this study, we evaluated the role of 67Ga whole-body and single photon emission tomographic (SPET) imaging in the early diagnosis and lesion localization of spinal epidural abscess before confirmation by gadolinium-enhanced magnetic resonance imaging (MRI). Six patients with fever of unknown origin had a 67Ga whole-body scan, four of whom also underwent SPET imaging. For further confirmation of a spinal epidural abscess, gadolinium-enhanced MRI was performed in all patients. All patients had increased 67Ga uptake in a spinal or paraspinal area on the whole-body scan. They were later confirmed to have a spinal epidural abscess after gadolinium-enhanced MRI. Of these six patients, five underwent surgical drainage plus parenterally administered antibiotics, and had complete or partial recovery. One died before operation due to sepsis. In conclusion, we suggest performing a 67Ga whole-body survey as early as possible in patients with fever of unknown origin, fever and back pain and/or the spinal syndrome, before MRI is performed. If a spinal epidural abscess is strongly suspected, SPET is needed for further confirmation of spinal versus non-spinal and contiguous versus non-contiguous lesion(s). If MRI is unavailable, then 67Ga scintigraphy is a satisfactory method for investigating spinal epidural abscesses.

Adult↗
PubMed2000

Rhodostomin inhibits the transforming growth factor-beta1-enhanced adhesion activity of ROS 17/2.8 osteosarcoma cells.

We have investigated the effect of transforming growth factor-beta1 (TGF-beta1) on the in vitro adhesion activity of the rat osteosarcoma cell lines (ROS 17/2.8) to extracellular matrix substrata, including fibronectin, type I and IV collagen, as well as laminin. The interaction of Arg-Gly-Asp (RGD) and rhodostomin, an RGD containing snake venom, with TGF-beta1 on the cell adhesion was also evaluated. The results showed that incubation with various concentration of TGF-beta1 (1-15 ng/ml) significantly increased the adhesion activity (1.4 to 2.5 folds) of ROS 17/2.8 to fibronectin and type I collagen (p<0.01), whereas the adhesion activity to laminin and type IV collagen was slightly elevated (1.1 to 1.5 folds). The peak effect of TGF-beta1 on the cell adhesion occurred after pretreatment of ROS 17/2.8 with TGF-beta1 for 6 hours. Treatment with Arg-Gly-Asp-Ser (RGDS) and rhodostomin effectively suppressed the TGF-beta1-enhanced adhesion activity to fibronectin and type I collagen. This study demonstrated that the up-regulated cell adhesion activity of ROS 17/2.8 cells by the TGF-beta1 can be inhibited by the rhodostomin.

Animals↗
PubMed2000

Physical activity, physical fitness, and osteopenia in postmenopausal Taiwanese women.

BACKGROUND AND PURPOSE: The purpose of this cross-sectional study was to investigate whether physical activity level and physical fitness parameters differ between postmenopausal Taiwanese women with normal and subnormal bone mineral density (BMD). METHODS: Seventy-six postmenopausal women aged from 42 to 65 years participated in this study. Women taking medication that might influence BMD measurements were not included. The BMDs of the lumbar spine (L2-4) and right femoral neck were measured using dual energy x-ray absorptiometry. Thirty-one women with both BMD values within the normal ranges (1.055 +/- 0.092 g/cm2 for the spine and 0.845 +/- 0.088 g/cm2 for the right femoral neck) of premenopausal Chinese women served as the normal density group. Another 43 women with both BMD values more than one standard deviation below the normal value (0.760 +/- 0.089 g/cm2 for the spine and 0.656 +/- 0.052 g/cm2 for the femoral neck) were recruited as the osteopenic group. Physical activity level was assessed with a 7-day recall questionnaire. Physical fitness assessment included tests of flexibility, muscular strength, endurance, body composition, and cardiopulmonary fitness. A multiple linear regression model adjusted for age, body weight, height, and years since menopause was used. RESULTS: The results revealed that energy expenditure and maximal oxygen consumption were significantly lower in the osteopenic group than in the non-osteopenic group (p < 0.05), while flexibility, body composition, muscle strength and muscular endurance did not differ significantly between the two groups (p > 0.05). CONCLUSIONS: These findings indicate that physical activity may play a major role in BMD levels in postmenopausal women in Taiwan. Future studies should emphasize the effect of physical exercise training on BMD in postmenopausal women.

Adult↗
PubMed2000

Subungual squamous cell carcinoma: report of 2 cases.

Subungual squamous cell carcinoma (SCC) is a rare malignant tumor with an indolent course. Its etiology is unknown. It often involves the distal phalanx of the thumb or the index finger, and often presents as a chronic ulcer that is commonly misdiagnosed as chronic paronychia, pyogenic granuloma or verruca vulgaris. Approximately 150 cases of subungual SCC, including one in a Taiwanese patient, have been reported. Here, we report two cases of subungual SCC presenting as a chronic ulcer of the nail bed refractory to antibiotic treatment. One case involved the right thumb, while the other involved the right index finger. Radiographs of both cases showed an osteolytic bone lesion involving the distal phalanx. Excision biopsy revealed SCC in both cases. Both patients received amputation of the involved distal phalanx and showed no signs of reoccurrence during 5 years of follow-up. These findings suggest that all recalcitrant ulcers of the nail bed should be biopsied to facilitate early diagnosis and treatment of subungual SCC.

Carcinoma, Squamous Cell↗
PubMed2000

Intracortical osteosarcoma: report of a case.

Intracortical osteosarcoma is the rarest anatomic variation of osteosarcoma. There have been only 12 cases reported in the English-language literature. We present a case of osteosarcoma in an 18-year-old Taiwanese man that originated within the cortex of the tibial diaphysis. The initial radiograph revealed a lytic mass confined to the cortex, mimicking a benign bone lesion. Histopathologic examination of the biopsy specimen showed an osteoblastic osteosarcoma mingled with some fibroblastic foci. He underwent en bloc resection, and a metallic prosthetic intercalary stem was used to replace the larger bone defect. Adjuvant chemotherapy was administered before and after the operation. He was free of disease during 40 months of follow-up. A review of all reported cases of intracortical osteosarcoma revealed that the initial method of treatment plays an important role in local recurrence and distant metastasis. Local excision and curettage leads to the worst results. The outcomes of more recently reported cases have improved because of early awareness of the possibility of malignancy and advances in chemotherapy. However, whether patients with intracortical osteosarcoma have a different prognosis from those with conventional osteosarcoma cannot be determined, because of the small number of intracortical osteosarcoma cases available for analysis.

Adolescent↗
PubMed1999

Lack of promotional effects of groundwater contaminant mixtures on the induction of preneoplastic foci in rat liver.

F344 rats were exposed to drinking water mixtures of seven of the most common groundwater contaminants associated with hazardous waste sites [arsenic, benzene, chloroform, chromium, lead, phenol, and trichloroethylene (TCE)] as the full mixture or submixtures of the organic and/or inorganic chemicals. The lowest concentrations (1x) of the individual chemicals were environmentally realistic and below what would be expected to induce significant short-term toxicity. This study was intended to determine if previously reported increases in localized hepatocellular proliferation in response to these chemicals might be correlated with increased risk for hepatocarcinogenesis. Rats were exposed via a drinking water solution to the full seven- chemical mixture (at 1x and 10x concentrations), submixtures of the organic or inorganic chemicals (at 10x concentrations), a mixture of TCE, lead, and chloroform (TLC submixture at 10x and 100x concentrations), or deionized water as a control. The rats were evaluated for promotion of placental glutathione-S-transferase (GST-P) positive preneoplastic liver cell foci after diethylnitrosamine (DEN) initiation and partial hepatectomy. Focus formation, cell proliferation, and apoptosis were evaluated after exposure to DEN or saline controls, the chemical mixtures or deionized water controls, or combinations of these treatments. The total number and area of GST-P positive foci in DEN-treated rats exposed to the full seven-chemical mixture was increased as compared with the DEN-water controls, but this was statistically significant only for total focus area in the 1x dose group. In DEN-treated rats, the inorganic or TLC submixtures resulted in a significant reduction in number and area of GST-P positive foci. Focus area also was decreased in the organic submixture-treated group, but not significantly. Hepatocellular proliferation was not significantly changed in the chemical mixture saline groups as compared with the mixture water controls. After DEN treatment, however, cell proliferation was significantly decreased after the 10x seven-chemical and organic mixture treatments and the 100x TLC mixture treatment. Different groups showed either increased or decreased apoptotic rates which did not correlate well with proliferation rates or focus formation. Mixtures of these seven chemicals, therefore, did not appear to act as promoters of hepatic foci at environmentally relevant concentrations, and some mixture combinations appeared to decrease promotional activity.

Animals↗
PubMed1999

The effectiveness of cyclic and continuous oral clodronate therapy on bone density and markers in osteopenic postmenopausal women.

Bisphosphonates have been used effectively to treat established osteoporosis and prevent postmenopausal bone loss. However, the optimal manner of its administration-whether cyclic or continuous-has not been well established. This study investigated the efficacy of cyclic and continuous oral administration of clodronate in 54 newly identified osteopenic postmenopausal women in a randomized, double-blind, crossover fashion. The participants were randomly separated into two groups. The cyclic group (n = 29) received 800 mg twice daily of oral clodronate for 2 weeks every 3 months for the first 12 months followed by placebo for the second 12 months. The continuous group (n = 25) received placebo in the first 12 months and ingested 400 mg of clodronate once daily for the second 12 months. The urinary amino-terminal (NTXtrade mark) and carboxy-terminal (CrossLapstrade mark) cross-linked fragments of type I collagen, both markers of bone resorption, showed a marked decrease (25-50%) with both regimens during the period of active treatment. In the cyclic group, the levels of these two markers increased in the second 12 months with placebo, but did not return to the baseline completely. However, bone mineral density (BMD), determined by dual-energy X-ray absorptiometry (DXA), showed no significant change of BMD at various sites after 1 year of active treatment in both groups. Thoracic and lumbar spine X-ray showed no new vertebral fracture in either group after 2 years of treatment. With the two treatment protocols in this study, oral clodronate was effective in decreasing postmenopausal bone resorption, causing no significant changes in BMD at various sites.

Absorptiometry, Photon↗
PubMed1999

Proximal femoral dimension in elderly Chinese women with hip fractures in Taiwan.

To investigate the relationship between proximal femoral geometry and the occurrence of hip fracture, we compared the geometry of contralateral normal hips of 120 elderly Chinese women with hip fractures, including 63 femoral neck fractures (group A) and 57 intertrochanteric fractures (group B) due to minor trauma, with that of 72 normal elderly Chinese women (group C). The mean ages for group A, B and C subjects were 77.3, 79.7 and 72.9 years, respectively. The femoral neck length (NL), neck width (NW), diameter of femoral head, femoral shaft width just below the lesser trochanter, and neck-shaft angle (theta;) were measured on the anteroposterior plain pelvic radiographs. The mean +/- SD of NL for group A was 50.4 +/- 3.3 mm; for group B, 50.6 +/- 3.1 mm; and for group C, 48.8 +/- 3.6 mm. Statistical analysis by ANOCOVA and regression showed that only NL of women with hip fractures was significantly longer than controls after correction for age, body height and weight (p <0.01). However, the difference in NL between group A and group B was not significant. By linear regression, the probability of fracture increased only with older age (p <0.001), longer NL (p <0.005) and lighter body weight (p <0.05). By logistic regression, each standard deviation increase in NL increased the risk of hip fracture (age-adjusted odds ratio 1.84; 95% CI, 1.11-3.06). The results confirm the relationship between proximal femoral geometry and the occurrence of hip fracture in elderly Chinese women in Taiwan.

Aged↗
PubMed1999

Factor of risk for hip fracture in normal Chinese men and women in Taiwan.

We have investigated the age-related change in factor of risk (Phi) for the proximal femoral load during free fall in 548 females and 240 males aged 21-79 years. These individuals were divided into either young (age <50 years) or old group (age >/=50 years). Another 26 females with hip fractures were included for comparison. The bone mineral density (BMD) of proximal femoral neck was measured by a Norland XR-26 dual-energy X-ray absorptiometer (DXA). The estimated fracture load (L) of femoral neck was calculated from the BMD with the regression equation derived by Courtney et al. [2,3] and estimated fall force (F) by body weight and height according to the regression equation derived by Nakamura et al. [6] respectively. Phi was defined as the quotient of F/L. The results showed an age-related decrease of BMD (P < 0.001) in both genders corrected for weight and height. By multiple linear regression analysis, the F decreased significantly with aging corrected for BMD in old males (partial r = -0.255, P < 0.01) and increased with aging in all females (young, partial r=0.287, p < 0.001; old, partial r = 0.252, P < 0.001). L decreased significantly with aging corrected for height and weight in males (young, partial r = -0.401, P < 0.01; old, partial r = -0.178, P < 0.05) and females (young, partial r = -0. 168, P < 0.05; old, partial r = -0.459, P < 0.001). However Phi decreased with aging in young males (P < 0.01) and females (young: P < 0.001, old: P < 0.001). Phi increased in old women but not in old men, and was higher in old women compared with old men. The 26 patients with hip fractures had a significantly higher Phi value than 85 age-matched women. In conclusion, Phi may provide a comprehensive comparison of the risk of hip fracture in the elderly population.

Absorptiometry, Photon↗
PubMed1999

Chronic toxicity and carcinogenicity studies of ethylenediamine dihydrochloride by dietary incorporation in Fischer 344 rats.

Ethylenediamine dihydrochloride (EDA.2HCl) was incorporated into the diet and fed to Fischer 344 rats for 2 years at target doses of 0, 0.02, 0.10 or 0.35 g/kg/day (equivalent to 0.009, 0.045 and 0.158 g free EDA/kg/day). Two separate untreated control groups were used. Interim sacrifices were at 6, 12 and 18 months and the terminal sacrifice was at 24 months. Under the conditions of this study, EDA.2HCl was not carcinogenic in the Fischer 344 rat. Most toxic responses were observed at the 12-month sacrifice and thereafter. Reductions in mean body weight gain were observed in high dose group male rats throughout most of the study and in the high dose group of female rats after approximately 18 months. Conversely, there was a slight increase in the mean body weight gain for the medium level female rats from about day 21 until 21 months that was of equivocal biological significance. Increased mortality was observed in the high dose group of both sexes and the mid dose group of female rats. The cause of the decreased survival was unclear, but may have been related to the enhancement of background degenerative lesions such as chronic nephropathy. Throughout the study, male rats from the high dose group had decreased erythrocyte counts, haemoglobin concentration and haematocrit. The cause and biological significance of the haematological changes were unknown. Increased water consumption was observed in the high dose group of both sexes during the latter half of the study. Increased urine volume with concurrent decreased urine specific gravity was generally observed in the high dose group of both sexes in the last half of the study and suggested a possible alteration in kidney function. Altered urine volume and specific gravity persisted to termination in female rats only. Slight increases in absolute and relative kidney weights were also observed in the high dose group of female rats during the latter half of the study. Hepatocellular pleomorphism was observed in the high dose group of both sexes, especially the female rats, and may have contributed to increased mean liver weights observed primarily in female rats from the high dose group. Hepatocellular pleomorphism was first observed in female rats at 12 months but was not observed in male rats until the final sacrifice. Rhinitis and tracheitis were observed with greater frequency in the high dose group of male rats at 12, 18 and 24 months and in high dose group female rats at 18 months. At 24 months, rhinitis, but not tracheitis, persisted at a significantly greater frequency in high dose group female rats. The apparent no-observable-effect level (NOEL) of this study was at the lowest dose level, 0.02 g/kg/day (equivalent to 9 mg EDA/kg/day).

Animals↗
PubMed1998

Antagonistic interactions of an arsenic-containing mixture in a multiple organ carcinogenicity bioassay.

Inorganic arsenic (As), 1,2-dichloroethane (DCE), vinyl chloride (VC) and trichloroethylene (TCE) are frequently identified as groundwater contaminants near hazardous waste disposal sites. While the carcinogenicity of each of these chemicals has been extensively studied individually, little information exists regarding their carcinogenic potential in combination. Therefore, we investigated the carcinogenic promoting potential of chemical mixtures containing arsenic, DCE, VC and TCE following multiple initiator administration in a multiple organ carcinogenicity bioassay (N. Ito, T. Shirai, S. Fukushima, Medium-term bioassay for carcinogens using multiorgan models, in: N. Ito, H. Sugano (Eds.), Modification of Tumor Development in Rodents, Prog. Exp. Tumor Res., 33, 41-57, Basel, Karger, 1991). Our results reveal a dose-responsive antagonistic effect of this four-chemical mixture on the development of preneoplastic hepatic lesions (altered hepatocellular foci and glutathione S-transferase pi positive foci) as well as bronchioalveolar hyperplasia and adenoma formation.

Animals↗
PubMed1998

Use of a medium-term liver focus bioassay to assess the hepatocarcinogenicity of 1,2,4,5-tetrachlorobenzene and 1,4-dichlorobenzene.

1,2,4,5-Tetrachlorobenzene (TeCB) and 1,4-dichlorobenzene (DCB) are important environmental contaminants that have been used extensively for a variety of industrial applications. Limited data are available in the literature regarding the carcinogenicity of TeCB. DCB has been shown to cause renal adenocarcinomas in rats and hepatic adenomas and carcinomas in mice at high doses in a 2-year study. In the studies presented here, we report that TeCB can promote the formation of preneoplastic foci and DCB cannot in a medium-term initiation/promotion assay. These results suggest that TeCB is a liver tumor promoter and that DCB is not at fairly low doses (0.1 and 0.4 mmol/kg per day).

Animals↗
PubMed1998

Enhanced regional expression of glutathione S-transferase P1-1 with colocalized AP-1 and CYP 1A2 induction in chlorobenzene-induced porphyria.

A distinct, nonfocal expression pattern was observed for glutathione S-transferase P1-1 (rGSTP1-1) in rats exposed to either hexachloro-(HCB) or pentachlorobenzene (PeCB). The nonfocal expression was localized to the centrilobular region with the most intense staining nearest the central vein. A Western blot analysis revealed a 5- and 15-fold induction of rGSTP1-1 with PeCB and HCB treatment on an equal molar basis, respectively. Evaluation of porphyrin fluorescence also revealed a centrilobular accumulation with average porphyrin measurements of 0.319, 0.590, and 0.206 micrograms/g tissue for PeCB, HCB, and corn-oil controls, respectively. Due to the role of Activator Protein-1 (AP-1) in rGSTP1-1 expression and CYP 1A2 in the pathogenesis of porphyria cutanea tarda, immunohistochemical localization of c-jun, c-fos, and CYP 1A2 was also performed. Increased expression and colocalization within the liver lobule was observed for c-jun, c-fos, CYP 1A2, rGSTP1-1, and areas of porphyrin accumulation. These observations are consistent with studies that have associated the induction of GST-P with jun- and fos-related gene products.

Animals↗
PubMed1998

Use of Biobrane in pediatric scald burns--experience in 106 children.

This report describes 141 scalded children admitted from January 1993 to June 1995. The mean age of patients was 2 yr 11 months. The average burn size was 11.4 percent TBSA. The male to female ratio was 1.6:1 (87:54). One hundred and six of the children were initially diagnosed as suffering from superficial or medium partial-thickness burns. After proper evaluation and resuscitation, all of them received immediate debridement and Biobrane coverage. This biosynthetic dressing was fixed with adhesive tape and compressive dressing. No splints were used. Pain tolerance was good and these children were able to resume their daily activities as early as possible. If vital signs were stable and Biobrane adherence occurred, the patients were discharged. The dressings were easily changed on an out-patient basis; therefore, the hospital stay and ultimate cost of burn care both decreased. This experience confirmed that Biobrane is quite suitable for consideration in treating pediatric scalds. Accurate diagnosis of depth is very important. The best results can be obtained only on superficial partial-thickness burns. A high wound infection rate occurred in the medium partial-thickness burn wounds (7.8 vs. 62.1 percent).

Activities of Daily Living↗