Biomedical subjects

D H Lee

Publications and source records attributed to D H Lee.

At least 127 records · Page 7Linked to original sources

PubMed2000

Tissue engineered artificial skin composed of dermis and epidermis.

We made an artificial skin comprised of a stratified layer of keratinocytes and a dermal matrix with a type I collagen containing fibroblasts. In this work, we showed keratinocyte behavior under primary culture, gel contractions varying with concentration of collagen solution, and cell growth plots in the collagen gel. The optimum behavior of dermal equivalent could be obtained using 3.0 mg/ml collagen solution and attached gel culture. The attached gel culture had a jumping effect of growth factor on cell growth at the lag phase. To develop the artificial skin, 1x10(5) cells/cm2 of keratinocytes were cultured on the dermal equivalent at air-liquid interface. Finally, to overcome the problem that artificial skin of collagen gel was torn easily during suturing of grafting, we prepared histocompatible collagen mesh and attached the mesh to the bottom of the gel. Cultured artificial skins were successfully grafted onto rats.

Animals↗

PubMed2000

Specific determination of endothelial cell viability in the whole cell fraction from cryopreserved canine femoral veins using flow cytometry.

Abstract: An efficient method for specifically determining the viability of endothelial cells (EC) from cells dissociated from the human saphenous vein was investigated. Three different methods, trypan blue staining assay, [3H]-proline incorporation assay, and flow cytometry (FCM), combined with the fluorescein isothiocyanate conjugated with Griffonia simplicifolia agglutins (GS1-FITC)/propidium iodide (PI) double staining, were used. Both trypan blue staining and [3H] proline incorporation assays demonstrated less sensitivity to determine viability of EC differentially from the other cells. FITC-GS1 showed prominent binding to the vascular EC and could be counted by FCM including PI on dead cells. Following the cryopreservation process, the GS1-FITC/PI FCM analytical method was adopted to test simultaneously the viability of whole cells and EC from the same tissue, human saphenous veins, and mongrel dogs' femoral veins after harvesting, antibiotic solution treatment, and thawing. The viability of the whole cells from veins decreased with a significant difference (p < 0.05) from that of EC after thawing.

Animals↗

PubMed2000

Ultrasound evaluation of flexor tendon lacerations.

Thirteen injured digits in 10 patients (10 hands) with 20 potentially injured flexor tendons were preoperatively evaluated using real-time ultrasonography. The time interval between injury and ultrasonographic evaluation averaged 22 days. If a complete tendon laceration was found, the location of the proximal tendon stump was determined. Surgery was performed an average of 4 days after the ultrasonographic evaluation to determine the accuracy of the ultrasound study. Ultrasonography accurately identified the status of the flexor tendon in 11 of 13 digits and in 18 of 20 flexor tendons (12 intact, 2 partial lacerations, and 6 complete tendon lacerations). With complete tendon lacerations the location of the proximal tendon stump was accurately identified in 5 of 6 digits. There were 2 false ultrasound findings, including incorrectly identifying a 75% laceration in an intact index flexor and a complete tendon laceration in a 75% lacerated index finger flexor. Ultrasonography can help to evaluate the preoperative status of injured flexor tendons and, in cases of completely lacerated tendons, can help identify the location of the proximal tendon stump.

Adolescent↗

PubMed2000

Second toe to index finger transfer.

Between April 1994 and May 1998, 15 amputated index fingers were treated based on three classifications: group 1 consisted of patients with index finger defects immediately proximal to, yet including, the distal interphalangeal joint, group 2 were those patients with defects from the proximal part of the distal interphalangeal joint to the distal part of the proximal interphalangeal joint and group 3 comprised patients with more proximal defects than group 2. With a total of six men and nine women, seven cases were included in group 1, five in group 2 and three in group 3. For the patients in groups 1 and 2, only a partial length of the second toe was transferred to the index finger, whereas in group 3 the total length of the toe needed to be transferred. The results can be summarised as follows:1. The two-point discrimination of the reconstructed index tip was 2.2 mm for group 1, 2 mm for group 2 and 2.3 mm for group 3.2. In group 1, the average range of motion in the transferred toe was 43.8>> in the distal interphalangeal joint. In groups 2 and 3, the average range of motion in the transferred toe was 30>> and 30.7>> in the distal interphalangeal joint, and 50>> and 39.3>> in the proximal interphalangeal joint, respectively.3. When compared with the contralateral index finger, the pinching power was measured at 83% in group 1, 70% in group 2 and 60% in group 3.4. Excellent results were obtained in group 1, good results in group 2 and fair results in group 3. Accordingly, the more proximal the defect in the index finger, the less satisfactory the result obtained.

Adult↗

PubMed2000

Lack of pre-emptive analgesic effects of local anaesthetics on neuropathic pain.

We investigated the significance of pre-emptive analgesia using a well-known model of neuropathic pain in rats. Lignocaine, bupivacaine or saline was applied locally to the left L5-L6 spinal nerve before or 4 days after nerve injury. Mechanical allodynia was then evaluated before and after injury. Pre- and post-injury treatment with local anaesthetics both resulted in a two- to threefold increase in the pain threshold, as manifested by a significant increase in von Frey measurements. However, this effect lasted only 24 h. Our study in rats questions the beneficial effect of a single dose of local anaesthetic as pre-emptive analgesia.

Anesthetics, Local↗

PubMed2000

Thermosoftening treatment of the nasotracheal tube before intubation can reduce epistaxis and nasal damage.

UNLABELLED: We evaluated whether a thermosoftening treatment with warm saline of a nasotracheal preformed tube can improve navigability through the nasal passageways and reduce epistaxis and nasal damage. A total of 150 patients were randomly allocated to three groups: Group I (untreated tube group, n = 50), Group II (35 degrees C treated tube group, n = 50), and Group III (45 degrees C treated tube group, n = 50). In Groups II and III, the tubes were softened at 35 +/- 2 degrees C and 45 +/- 2 degrees C with warm saline, respectively. In Group I the tube was prepared at room temperature (25 +/- 2 degrees C). The incidence of epistaxis and nasal damage in Groups II and III was significantly less than that of Group I (P: < 0.05). Despite the more frequent incidence of smooth passage in Group III, no statistical difference was found among the groups. Logistic regression analysis also confirmed that epistaxis was more likely to be reduced when the tube had been thermosoftened (odds ratio = 1.46, 95% confidence interval = 1.02, 2.11). We conclude that simple thermosoftening treatment of the nasotracheal tube with warm saline helps to reduce epistaxis and nasal damage. IMPLICATIONS: Thermosoftening treatment of a nasotracheal tube with warm saline before intubation can effectively reduce epistaxis and nasal damage. This technique is safe, easy, and suitable for all types of tubes and does not require additional implements.

Adult↗

PubMed2000

Replantation of avulsed scalps and secondary aesthetic correction.

Five patients with avulsed scalps were treated with replantation between 1992 and 1998. All patients were women age 20 to 36 years. The percentage of the avulsed scalp ranged from 50% to 100% of the whole scalp. The vessels chosen for anastomosis were the superficial temporal artery, occipital artery, and superficial temporal vein. A vein graft harvested from the cephalic vein of the forearm was performed on the venous and arterial sides in 1 patient. Two patients experienced complete survival of the replanted scalp. Three patients showed 40%, 50%, and 80% survival areas, with the remaining defects resurfaced as split-thickness skin grafts. Six months later, the scar areas in the last 3 patients were reconstructed with an expansion of the normal or replanted scalp. The follow-up period ranged from 1 to 7 years. In 4 patients a partial return of sensation in the replanted scalp and motor function of the frontalis muscle were observed. All patients were satisfied with the aesthetic results of their surgery.

Adult↗

PubMed2000

Balloon catheter dilation in common canalicular obstruction of the lacrimal system: safety and long-term effectiveness.

PURPOSE: To evaluate the safety and long-term effectiveness of balloon catheter dilation in the treatment of common canalicular obstruction of the lacrimal system. MATERIALS AND METHODS: Fluoroscopically guided dilation with a 3-mm-diameter balloon catheter was attempted in 195 eyes of 148 patients (26 men, 122 women; mean age, 57 years; age range, 33-78 years) with epiphora due to common canalicular obstruction. Eighty-four of 195 eyes had complete obstruction, and 111 had partial obstruction. RESULTS: Complications were self-limited nasal bleeding (n = 8), false passage (n = 7), and extravasation of contrast material (n = 6). Initial technical success was achieved in 76 (90%) of 84 eyes with complete obstruction and in 104 (94%) of 111 eyes with partial obstruction. In the 180 eyes with technical success, immediate clinical improvement was achieved in 76 eyes with complete obstruction and in 100 eyes with partial obstruction. The mean follow-up period was 36 weeks (range, 4-168 weeks). The cumulative patency rates were 51% at 6-month, 43% at 12-month, and 40% at 24-month follow-up. CONCLUSION: Although the long-term recurrence rate is relatively high, balloon catheter dilation is a safe and effective therapeutic technique to be used initially in common canalicular obstruction.

Adult↗

PubMed2000

Covered retrievable expandable nitinol stents in patients with benign esophageal strictures: initial experience.

PURPOSE: To investigate the safety and clinical effectiveness of covered retrievable expandable nitinol stents in 25 patients with a benign esophageal stricture. MATERIALS AND METHODS: Under fluoroscopic guidance, covered retrievable expandable nitinol stents were placed in 25 patients with a benign esophageal stricture and were removed with a retrieval hook 1-8 weeks later. RESULTS: Stent placement was successful in all patients, with no procedural complications. After stent placement, all patients could ingest solid food. The stents were successfully removed from all but two patients. One patient passed the stent via the rectum, and the other regurgitated a high cervical stent. After stent removal, one patient developed a small esophagobronchial fistula, which spontaneously sealed within 1 week of stent removal. After stent removal or migration, all patients could ingest solid food. During follow-up (mean, 13 months; range, 2-25 months) after stent removal or migration, 12 patients maintained their improvement in dysphagia and needed no further treatment. Thirteen patients with recurrence were treated by means of repeat balloon dilation. CONCLUSION: Use of retrievable expandable nitinol stents seems to be a safe and effective method of treatment in selected patients with benign esophageal strictures.

Adult↗

PubMed2000

Measurement of surface area in human mastoid air cell system.

The total surface areas of human mastoid air cells were measured using digital CT scans. Using 24 normal ears, the lining of the mastoid air cells was digitally scanned, traced and analysed. The mean surface area of the mastoid air cell system was 167.0 cm2 and ranged from 74.78 to 330.01 cm2. The volume was also measured, the mean being 10.43 cm3 ranging from 6.25 to 20.52 cm3. The correlation coefficient between surface area and volume was 0.95. These results indicate that well pneumatized mastoid air cells serve to provide an extremely large surface area in the temporal bone which in normal mastoid air cells is proportional to the volume.

Adult↗

PubMed2000

Apoplexy of pituitary macroadenoma after combined test of anterior pituitary function.

Pituitary apoplexy has been reported as a very rare complication of combined tests of anterior pituitary function and of TRH or gonadotropin-releasing hormone (GnRH) administration in pituitary tumor. A 34-year-old man with a GH-secreting pituitary macroadenoma and diabetes mellitus received an injection of 400 microg TRH, 100 microg GnRH, and 0.15 U/Kg regular insulin. Twenty minutes later, he complained of a severe headache and vomited. Visual acuity and visual field did not change and his headache was persistent during the next 24 hours of conservative management. Magnetic resonance imaging (MRI) of the sella turcica done the day after the event showed definitive elevation of the optic chiasm and slight enlargement of tumor and focal areas of mixed high signal and low signal intensities in the macroadenoma on noncontrast T1-weighted images. Headache subsided markedly within a day of octreotide therapy. Transsphenoidal removal of the pituitary tumor was performed 9 days after the hormone study. Ischemic necrosis and hemorrhage were confirmed in the acidophilic adenoma with positive immunostaining for GH. Postoperative course was uneventful and his serum insulin-like growth factor-1 (IGF-1) level and blood glucose levels were normalized. Three months after the surgery the dynamic test was repeated without adverse effects. To our knowledge, this is a very rare case of apoplexy of GH-secreting pituitary adenoma after a combined stimulation test of anterior pituitary function.

Acromegaly↗

PubMed2000

Platelet substitutes and novel platelet products.

Despite many advances in the safety, processing and storage of conventional 22 degrees C liquid-stored allogeneic platelet concentrates, there are still significant drawbacks to standard platelet concentrates used in transfusions for patients with thrombocytopenia. Efforts to overcome these shortcomings have been undertaken in both academic and commercial settings, resulting in an array of novel platelet products and substitutes that are currently at various stages of development. This review summarises the recent developments in lyophilised platelets, infusible platelet membranes (IPM), red cells bearing arginine-glycine-aspartic acid (RGD) ligands, fibrinogen-coated albumin microcapsules and liposome-based agents as putative alternatives to conventional transfusions involving allogeneic platelet concentrates. These various products are designed to replace the use of allogeneic donor platelets with modified or artificial platelets, to augment the function of existing platelets and/or provide a procoagulant material capable of achieving primary haemostasis in patients with thrombocytopenia. Preclinical studies have been encouraging for several of these platelet substitutes and novel platelet products, however, to date, only a few of these products have entered human trials. With the ongoing development of these diverse products, properties necessary for haemostatic effectiveness will become apparent. Safety and efficacy, however, must be demonstrated in preclinical and Phase I - III clinical trials, before these novel agents can be used clinically for patients with thrombocytopenia.

Animals↗

PubMed2000

Intestinal parasite infections at an institution for the handicapped in Korea.

Stool and cellotape anal swab examinations were carried out in August 1997 on handicapped people at an institution located in Chorwon-gun, Kangwon-do, Korea. A total of 112 stool samples (78 males and 34 females) revealed three cases of Trichuris trichiura infection and one case of Enterobius vermicularis infection. Other helminth eggs were not detected. The overall prevalence rate was 35.7% (38.5% for males and 29.4% for females). More than two different kinds of parasites were found in 42.0% of the positive stool samples (17 cases). The infection rates for protozoan cysts are as follow: Entamoeba coli (25.0%), E. histolytica (1.8%), Endolimax nana (21.4%), Iodoamoeba bütschlii (1.8%) and Giardia lamblia (0.9%). In cellotape anal swab examinations (165 samples), the prevalence rate of E. vermicularis was 20.6% (25.7% of males and 9.6% of females). In conclusion, the handicapped people in the institution showed higher infection rates of protozoan parasites and E. vermicularis, possibly due to more accessibility to the infection.

Adolescent↗

PubMed2000

Viability of cells in cryopreserved canine cardiovascular organs for transplantation.

To determine applicability of the cryopreservation procedure for vessel grafts, the viability of endothelial cells (ECs) among the whole cells in three kinds of organs artery, vein, trachea in mongrel dogs was evaluated on the basis of histological analysis. The Griffonia simplicifolia agglutins-fluorescein isothiocyanate (GSA-FITC) and propidium iodide (PI) double staining methods were combined with flow cytometry (FCM), which was able to simultaneously determine the viability of whole cells and ECs from the same tissue, were performed after harvesting, after antibiotic solution treatment, and after cryopreservation and thawing. In most cases, the viability of ECs is lower than that of whole cells from veins and arteries. The viability of whole cells in veins was maintained until the antibiotic solution treatment and then decreased significantly after cryopreservation and thawing, while the ECs began to decrease significantly after the antibiotic solution treatment and more markedly decreased after thawing. The viability of ECs and whole cells from arteries was similar to that of the veins' conditions. The viability of whole cells from the trachea decreased with a similar pattern to that of the ECs from vessels. In consideration of maintaining cell viability among the three kinds of organs, the viability of arteries was better than that of the others. The cells in the trachea demonstrated a lower viability than the vessels. The effect of antibiotic solution treatment on the reduction of cell viability depends on the treatment time and temperature.

Animals↗

PubMed2000

Non-Hodgkin's lymphoma of the thyroid and adrenal glands.

We report a case of non-Hodgkin's lymphoma(NHL) with simultaneous involvement of both thyroid and bilateral adrenal glands. Literature review on a computerized search showed that this is an extremely rare condition. The final diagnosis of diffuse large B cell lymphoma was confirmed by biopsies of thyroid gland, enlarged cervical lymph node, and adrenal gland. The significant endocrine dysfunction of the thyroid, adrenal or other endocrine glands was absent in our case. The patient responded dramatically to three cycles of chemotherapy with no complication or endocrine dysfunction and continues to be followed.

Adrenal Gland Neoplasms↗

PubMed2000

Incidence and characterization of Listeria monocytogenes from domestic and imported foods in Korea.

A total of 1,537 domestic and imported food products were examined for the incidence of Listeria monocytogenes between 1993 and 1997 in Korea. L. monocytogenes was detected using the U.S. Department of Agriculture isolation method. Isolated L. monocytogenes was confirmed by polymerase chain reaction with hly1 and hly2 primers designed from the listeriolysin O. Overall, 122 samples (7.9%) contained L. monocytogenes. The rate of isolation was 4.3% for beef, 19.1% for pork, 30.2% for chicken, 1.2% for shellfish, 4.4% for raw milk, 4.4% for frozen smoked mussels, and 6.1% for ice cream. No L. monocytogenes was found in pasteurized milk, pasteurized processed cheese, saltwater fish, dried seafoods, or ham. The overall incidence was lower than that reported in previous studies from other countries. Most isolates were serotype 1/2b except for chicken, in which serotype 1/2a was predominant. The serotyping results might imply the presence of food or geography-specific L. monocytogenes strains.

Animals↗

PubMed2000

Treatment of prostatic abscess: value of transrectal ultrasonographically guided needle aspiration.

The purpose of this study was to assess the effectiveness of transrectal ultrasonographically guided needle aspiration in the treatment of prostatic abscess. Fourteen patients with prostatic abscess were evaluated with this technique and treated with sonographically guided needle aspiration. Using this technique, all cases (100%) had one or more hypoechoic areas within the prostate that contained inhomogeneous materials; in 10 patients (71.0%), the lesion showed internal septa or solid portion. The margins of the hypoechoic area were well defined and thick in 11 patients (79.0%) and poorly defined in 3 patients (21.0%). The estimated volume of the prostatic abscess ranged between 2 and 28 ml (mean, 12.0 ml). The presence of a pus collection within the prostate was confirmed by transrectal ultrasonographically guided aspiration in all patients. However, successful treatment of prostatic abscess with transrectal needle aspiration was done in 12 (86.0%) of 14 patients; the treatment failed in 2 (14.0%) of 14 patients. One patient was treated with perineal incision and drainage and the other with transurethral resection. The amount of pus drained ranged between 1 and 39 ml (mean, 12.0 ml). On follow-up transrectal ultrasonographic examination, no remaining abscess pocket was found within the prostate in any of the cases. One year later, the prostatic abscess recurred in one case. In conclusion, transrectal ultrasonographic guidance is useful in the diagnosis of prostatic abscess as well as in the guidance for aspiration and the drainage of such abscesses. Transrectal ultrasonographically guided needle aspiration could be an effective method for treating prostatic abscess.

Abscess↗

PubMed2000

Effect of the factor V Leiden mutation on the clinical expression of severe hemophilia A.

To determine whether the factor V Leiden mutation is associated with decreased bleeding in individuals with severe hemophilia A, factor concentrate utilization, maximum annual number of bleeding episodes, and the prevalence of hemophilic arthropathy between carriers and non-carriers of the factor V Leiden mutation were compared. Heterozygosity for the factor V Leiden mutation was found in 6 of 137 subjects (4.4%). Carriers of the factor V Leiden mutation utilized less factor concentrate (geometric mean: 310 vs. 1185 units/kg/year) and had fewer bleeding episodes than non-carriers (proportion with 10 or fewer bleeding episodes in their worst year: 50 vs. 11%). However, the factor V Leiden mutation was not associated with the absence of arthropathy. The intron 22 inversion mutation of the factor VIII gene was tested for in a subgroup of 80 subjects, but it was not found to be a significant variable for any of the bleeding endpoints. The results of this small study are consistent with the hypothesis that the factor V Leiden mutation imparts a protective effect; however, a larger confirmatory study in which the factor VIII molecular defects can be controlled for is needed. Furthermore, most severe hemophiliacs who used fewer than 200 units/kg/year of factor concentrate or who had experienced 10 or fewer bleeding episodes per year did not carry the factor V Leiden mutation, suggesting that the proportion of severe hemophiliacs whose mild clinical course can be attributed to the factor V Leiden mutation is small.

Adolescent↗