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Abstract
Browsing through some literatures, I happened to find out some records on the rite of imitation of the child's head to brachycephaly. In 1976, two skulls showing extraordinary forms were excavated out of an ancient tomb at Yean village of Daedong township in Kimhae County in Kyungnam Province, the Republic of Korea. The deformation in Yean village is judged to be an intentional frontal flattening. The frontal bone of deformed individuals is remarkably flattened by a primary deforming force. The parietal bone expands laterally and superoposteriorly as a major compensatory growth. The lambdoid or occipital flattening induced by the counterforce is light and unstable. In the facial skeleton, the maxilla shifts downward as a minor compensatory growth. These findings might be substantially correspondent to the custom in the southern area of Korea in the 4th century A.D. paragraphed by Han chuan of Wei-dynasty record, History of the Three Kingdoms. It described that the people gave a pressure onto the child's forehead with stones in order to mold it for preference. Flatheaded meant "free" among the Chinook and Salish tribes of American Indians. Babies of slaves were denied the year-long beauty treatment--a board tied to the infants' padded skull--that permanently flattened the foreheads of tribal members. Referring to these records, I presume that brachycephaly can be induced by direct extrinsic pressure at least until the soft infant's head gets hard.
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102
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Hwang W, Kim H, Lee E, Lim J, Roh S, Shin T, Hwang K, Lee B. Purification and embryotropic roles of tissue inhibitor of metalloproteinase-1 in development of "HanWoo" (Bos taurus coreanae) oocytes co-cultured with bovine oviduct epithelial cells. J Vet Med Sci 2000; 62:1-5. [PMID: 10676882 DOI: 10.1292/jvms.62.1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
This study was conducted to purify a tissue inhibitor of metalloproteinase (TIMP)-1 in a serum-free medium conditioned with bovine oviduct epithelial cells (BOEC) and to evaluate its effect on development of "HanWoo" (Bos taurus coreanae) embryos to the blastocyst stage. In the first study using SDS-PAGE electrophoresis, the presence of 32 kDa proteins, which contains TIMP-1, was detected in the medium conditioned with BOEC, and TIMP-1 was then purified from the medium by gel filtration and HPLC techniques. When examined TIMP-1 secretion, fluorescent foci indicating the secretion of TIMP-1 were found after stained BOEC with fluorescein isothiocyanate. In the next experiment, two-cell embryos derived from in vitro-fertilization were cultured in a serum-free medium, to which 0, 1.25, 2.5 or 5 microg/ml of purified TIMP-1 was supplemented. More (P<0.05) embryos developed to the morula and blastocyst stages after the addition of 2.5 microg/ml to culture medium than after no addition. In conclusion, our data indicate that BOEC secrete TIMP-1 and this glycoprotein promotes the prehatched development of "HanWoo" embryos derived from in vitro-fertilization.
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103
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Seo B, Yun J, Lee S, Kim M, Hwang K, Kim J, Min KR, Kim Y, Moon D. Barbarin as a new tyrosinase inhibitor from Barbarea orthocerus. PLANTA MEDICA 1999; 65:683-686. [PMID: 10630104 DOI: 10.1055/s-1999-14092] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A tyrosinase inhibitor was isolated from the whole plant of Barbarea orthocerus Led. (Brassicaceae) by activity-guided fractionation, and identified as (R)-5-phenyl-2-oxazolidinethione (barbarin) by structural analysis followed by comparison with reported spectral data. The compound exhibited significant inhibitory effects on mushroom and murine tyrosinases at more than 1.6 x 10(-5) M. Barbarin exhibited IC50 values of 4.2 x 10(-5) M on mushroom tyrosinase and of 4.8 x 10(-5) M on murine tyrosinase. Kojic acid as a positive control exhibited IC50 values of 3.4 x 10(-5) M and 6.0 x 10(-5) M on mushroom and murine tyrosinases, respectively. Therefore, barbarin exhibited a similar level of inhibitory potency with kojic acid used as a positive control. In a kinetic study with various concentrations of L-dopa as the substrate, barbarin was identified as an uncompetitive inhibitor and kojic acid as a mixed inhibitor of both mushroom and murine tyrosinases. Barbarin exhibited KEIS values of 3.3 x 10(-5) M and 3.6 x 10(-5) M on mushroom and murine tyrosinases, respectively. Kojic acid exhibited KEIS and KEI values of 2.4 x 10(-5) M and 2.2 x 10(-5) M on mushroom tyrosinase and those of 8.9 x 10(-5) M and 7.2 x 10(-5) M on murine tyrosinase, respectively.
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104
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Hwang K, Lee DK, Lee SI. Tenosynovial giant cell tumor of finger, localized type: a case report. J Korean Med Sci 1999; 14:682-4. [PMID: 10642950 PMCID: PMC3054441 DOI: 10.3346/jkms.1999.14.6.682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The authors report a typical case of tenosynovial giant cell tumor of the right middle finger of a 31-year-old man. Histologically, this tumor is characterized by a discrete proliferation of rounded synovial-like cells accompanied by a variable number of multinucleated giant cells, inflammatory cells, and xanthoma cells. Clinicopathologically, this tumor is a benign lesion that nonetheless possesses a capacity for local recurrence. Local excision with a small cuff of normal tissue is the treatment of choice in this tumor.
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Abstract
The authors describe a simple technique for reducing zygomatic arch fractures with a towel clip. The orbital rim and zygomatic arch are outlined with a marking pen. The exact fracture site is then marked by palpation. The depressed fracture site is held with a towel clip and pulled outward gently. A clicking noise may be heard. The clip is then released. The contour of the zygomatic arch is compared with the other side. Using this technique the authors reduced 11 fractured zygomatic arches (arch only, displaced medially) in 11 patients and the results were satisfactory in all patients. The towel clip method is one procedure to reduce zygomatic arch fracture.
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106
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Abstract
New instrumentation and techniques for skeletal fixation have been developed in response to concerns regarding variability of the skull base and the calvaria. The fear of intracranial penetration has limited the use of internal or external fixation to the skull base and the calvaria. Despite potential clinical usefulness, limited anthropometric data have been reported on the skull base and the calvaria. The purpose of this study was to measure the average thickness of various points of the skull base and the calvaria of Korean adults. Fifty-one Korean adult skull bases and calvaria, which were cut 2 cm above the supraorbital margin anteriorly and 2 cm above the inion posteriorly, were measured in this study. Thickness of 13 clinically important points were measured with a Teclock GM-21 Calipergauge (Teclock Co., Tokyo, Japan). The mean thickness of the two opposite sides were compared using paired t-tests. They did not differ significantly from the others except for three points. Frontal bone A (located 1 cm above the supraorbital margin and 1.5 cm lateral to the midline) was 6.35 +/- 2.88 mm, frontal bone B (located at the midpoint of the frontal midpoint and the frontoparietal suture on the cut edge) was 5.24 +/- 1.50 mm, frontal bone C (located at the midpoint of the vertex and frontal bone B) was 6.63 +/- 1.77 mm, the pterion was 3.19 +/- 0.85 mm, the midpoint of the squamous temporal was 1.96 +/- 0.65 mm, parietal bone A (located 1.5 cm below the middle meningeal groove) was 3.99 +/- 1.11 mm; parietal bones B and C (divided at the distances between the frontoparietal suture and the occipital midpoint with a ratio of 1:3 and 2:3 respectively on the cut edge) were 4.71 +/- 1.06 mm and 5.35 +/- 0.91 mm respectively, occipital bone A (located 1.5 cm posterolateral from the foramen magnum) was 2.31 +/- 1.00 mm, occipital bone B (located 1.5 cm lateral to the midline and 0.5 cm above the inion) was 5.41 +/- 1.50 mm, occipital bone C (located occipital to the midpoint and 2 cm above the inion) was 8.2 +/- 1.67 mm, the orbital roof was 1.37 +/- 1.08 mm, and the orbital lateral wall was 2.25 +/- 1.06 mm. The data give practical information for determining the position and depth for safe and effective internal or external fixation during craniofacial procedures.
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107
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Hwang K, Jeong DW, Lee JW, Kim IH, Chang HI, Kim HJ, Kim IY. Alteration of the NAD+/NADH ratio in CHO cells by stable transfection with human cytosolic glycerol-3-phosphate dehydrogenase: resistance to oxidative stress. Mol Cells 1999; 9:429-35. [PMID: 10515608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023] Open
Abstract
The intracellular level of the NAD+/NADH ratio plays a vital role in sustaining and coordinating the catabolic reaction of the cell, and reflects the redox state of cytosol. Antioxidants play a role to protect cytosol and membrane from free radicals. This role of antioxidants involves sustaining cell viability and the procedure is thought to be regulated by the equilibrium of the redox state of the cell. However, there is very little known about how the NAD+/NADH level is set and changed. To alter the ratio, human NAD-dependent glycerol-3-phosphate dehydrogenase (cGPDH) cDNA was transfected stably in CHO dhfr- cells. When compared to parental CHO cells, cGPDH activities of the transfected cells were increased 8-12 fold, but the NAD+/NADH ratio was decreased. Specific growth rate of the transfected cells was similar to or slight lower than that of wild type CHO cells. Cell viability of the stable transformants against H2O2 was increased without change of either catalase or glutathione peroxidase activity. However, the increase of cell viability was correlated with the decrease of NAD+/NADH ratio in transfectants. From these results, it is suggested that the overexpression of cGPDH changes the NAD+/NADH ratio toward a decrease, and by this change in the redox state the cell confers more resistance against H2O2.
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108
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Hollinger JO, Schmitt JM, Hwang K, Soleymani P, Buck D. Impact of nicotine on bone healing. JOURNAL OF BIOMEDICAL MATERIALS RESEARCH 1999. [PMID: 10321701 DOI: 10.1002/(sici)1097-4636(19990615)45] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
A limited number of experimental animal studies and in vitro data confirm that nicotine impairs bone healing, diminishes osteoblast function, causes autogenous bone graft morbidity, and decreases graft biomechanical properties. Therefore, our long-term goal is to develop an effective therapy to reverse the adverse impact of nicotine from tobacco products. However, before accomplishing this goal, we had to develop an animal model. Our hypotheses were nicotine administration preceding and following autogenous bone grafting adversely affected autograft incorporation and depressed donor site healing in a characterized animal wound model. Hypothesis testing was accomplished in bilateral, 4-mm diameter parietal bone defects prepared in 60 Long-Evans rats (male, 35-day-old). A 4-mm diameter disk of donor bone was removed from the left parietal bone and placed in the contralateral defect. The donor site served as a spontaneously healing bone wound. The rats were partitioned equally among three doses of nicotine administered orally in the drinking water (12.5, 25, and 50 mg/L). For each dose, the duration and sequence of nicotine treatment followed four courses, including no nicotine and designated combinations of nicotine administration and abatement prior to and following osseous surgery. Experimental sites were recovered on 14 and 28 days postsurgery, responses quantitated, and data analyzed by analysis of variance and post hoc statistics (p < or = 0.05). We developed a convenient and effective osseous model, and the results validated our hypothesis that nicotine negatively impacts on bone healing.
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109
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Hwang K, Kim DJ. Attachment of the deep temporal fascia to the zygomatic arch: an anatomic study. J Craniofac Surg 1999; 10:342-5. [PMID: 10686884 DOI: 10.1097/00001665-199907000-00012] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
It is generally acknowledged that the superficial layer of the deep temporal fascia attaches to the lateral surface and its deep layer along the medial surface of the zygomatic arch. However, Ramírez asserts that the superficial and the deep layer of the deep temporal fascia fuse consistently approximately 1 cm above the upper ridge of the arch and attach to the outer surface of the arch, blending with the superficial fascia of the masseter muscle. In this study the authors clarify the precise anatomic relations between the fascia and the zygomatic arch. Coronal sections crossing the midpoint between the zygomaticotemporal suture and the tubercle of zygoma were observed grossly and histologically in 32 hemifaces from 16 Korean adult cadavers. This study demonstrates that the superficial and the deep layers of the deep temporal fascial fuse and insert onto the superior margin of the arch in 18 dissections (56%) and insert onto the superolateral surface in 14 dissections (44%). The contacting surface of the fused deep temporal fascia to the periosteum of the zygomatic arch is less than 2 mm. The following route is safer and is recommended for reaching the zygomatic arch region: Just above the split of the deep temporal fascia, a dissection is carried through the deep temporal fasica, continuing downward to the superior margin of the arch along the undersurface of the fascia. At this spot the periosteum of the arch is dissected.
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110
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Hollinger JO, Schmitt JM, Hwang K, Soleymani P, Buck D. Impact of nicotine on bone healing. JOURNAL OF BIOMEDICAL MATERIALS RESEARCH 1999; 45:294-301. [PMID: 10321701 DOI: 10.1002/(sici)1097-4636(19990615)45:4<294::aid-jbm3>3.0.co;2-1] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
A limited number of experimental animal studies and in vitro data confirm that nicotine impairs bone healing, diminishes osteoblast function, causes autogenous bone graft morbidity, and decreases graft biomechanical properties. Therefore, our long-term goal is to develop an effective therapy to reverse the adverse impact of nicotine from tobacco products. However, before accomplishing this goal, we had to develop an animal model. Our hypotheses were nicotine administration preceding and following autogenous bone grafting adversely affected autograft incorporation and depressed donor site healing in a characterized animal wound model. Hypothesis testing was accomplished in bilateral, 4-mm diameter parietal bone defects prepared in 60 Long-Evans rats (male, 35-day-old). A 4-mm diameter disk of donor bone was removed from the left parietal bone and placed in the contralateral defect. The donor site served as a spontaneously healing bone wound. The rats were partitioned equally among three doses of nicotine administered orally in the drinking water (12.5, 25, and 50 mg/L). For each dose, the duration and sequence of nicotine treatment followed four courses, including no nicotine and designated combinations of nicotine administration and abatement prior to and following osseous surgery. Experimental sites were recovered on 14 and 28 days postsurgery, responses quantitated, and data analyzed by analysis of variance and post hoc statistics (p < or = 0.05). We developed a convenient and effective osseous model, and the results validated our hypothesis that nicotine negatively impacts on bone healing.
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111
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Hwang K. Evaluation of the Quality of Surgical Gloves Among Four Different Manufactures. ANNALS OF OCCUPATIONAL HYGIENE 1999. [DOI: 10.1016/s0003-4878(99)00024-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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112
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Schmitt JM, Hwang K, Winn SR, Hollinger JO. Bone morphogenetic proteins: an update on basic biology and clinical relevance. J Orthop Res 1999; 17:269-78. [PMID: 10221845 DOI: 10.1002/jor.1100170217] [Citation(s) in RCA: 241] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The regeneration of bone is a remarkable, complex physiological process, and BMPs are a formidable clinical tool to promote its regeneration. By defining roles played by BMPs in developmental biology and bone regeneration, significant progress has been made to identify cell-signaling molecules and their regulators. For example, the regulators of BMPs that include noggin, chordin, cerberus, dan, and gremlin may be harnessed as therapies to offset calcification encountered after total hip arthroplasties. Furthermore, exploiting BMPs and Smads may generate new therapeutic options for bone repair. Another compelling clinical consideration is the trans-acting factor osteoblast-specific factor-2, which can promote osteoblast differentiation. Moreover, the affiliation of osteoblast-specific factor-2 with heritable disorders merits exploration. A recognized daunting challenge includes a carrier/delivery system for the powerful morphogenetic therapeutic tools, as well as osteoprogenitor cells and intracellular transduction and transcriptional factors. In addition, the long-term effects of administering superphysiological doses of rhBMPs to patients must be assessed systematically. A new generation carrier/delivery system may be the answer to offset dosing liabilities as well as to provide residence for exogenous, BMP-receptive osteoprogenitor cells (111,112). The areas highlighted in this review offer fertile territory for thought and research to develop rational clinical treatments to promote bone regeneration and to understand some of the biological roles of BMPs.
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113
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Abstract
When operating in and around the orbit, the key to a successful result is precise anatomical localization. However, there is no precise study about the localization of vital orbital structures from reliable periorbital bony anatomy of the Korean adult. This study was constructed to give pertinent anatomical measurements to which the plastic and maxillofacial surgeon may refer. The 82 orbits obtained from 41 skulls of adult Koreans were measured with Vernier calipers and Marshac calipers. Superiorly, the supraorbital fissure was 40.0 +/- 2.5 mm from the supraorbital notch. Medially, the posterior ethmoidal foramen was 31.7 +/- 3.0 mm from the anterior lacrimal crest. Inferiorly, the infraorbital fissure where the infraorbital groove started was 26.4 +/- 2.6 mm from the infraorbital foramen. Laterally, the supraorbital fissure was 34.3 +/- 2.7 mm from the frontozygomatic suture. These distances are suggested as appropriate safe distances from each periorbital bony landmark. Dissection beyond that distance should be done with great caution.
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114
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Hwang K, Kim DJ, Chung RS, Lee SI, Hiraga Y. An anatomical study of the junction of the orbital septum and the levator aponeurosis in Orientals. BRITISH JOURNAL OF PLASTIC SURGERY 1998; 51:594-8. [PMID: 10209461 DOI: 10.1054/bjps.1998.0300] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The anatomical relationships of the orbital septum and levator aponeurosis has been studied in 40 eyelids subjected to blepharoplasty and corrective ptosis surgery by dissection in 10 cadavers and in histological sections. The orbital septum originates from the arcus marginalis of the frontal bone and consists of two layers. The whitish outer (superficial) layer, containing vertically running vessels, descends just inside the orbicularis oculi muscle to interdigitate with the levator aponeurosis with loose connective tissue, then disperses inferiorly. The inner (deep) layer follows the superficial one initially, then reflects at the levator aponeurosis and continues posteriorly with the levator sheath. We reconfirmed Whitnall's original description that the levator sheath thickens to form the superior transverse ligament runs continuously inferiorly anterior to the levator aponeurosis and forms the inner layer of the orbital septum. This detailed anatomical analysis should assist in performing upper eyelid surgery such as the Oriental double fold operation or levator resection.
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115
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Choi YH, Fischer E, Hoda SA, Rubenstein WA, Morrissey KP, Hertford D, Hwang K, Ramirez de Arellano E, Kazam E. Appendiceal CT in 140 cases. Diagnostic criteria for acute and necrotizing appendicitis. Clin Imaging 1998; 22:252-71. [PMID: 9699047 DOI: 10.1016/s0899-7071(97)00080-6] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Computed tomography (CT) was performed in 140 patients with suspected acute appendicitis. Thin collimation (5 mm), intravenous contrast enhancement, 1-second scan times, and supplementary cecal air insufflation were emphasized. CT accuracy was 98% overall (137/140), and 99% in the 124 cases with early surgery. Necrotizing appendicitis was diagnosed by CT with 86% accuracy and 90% positive predictive value.
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116
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Hwang K, Baik SH. Distribution of hairs and sweat glands on the bodies of Korean adults: a morphometric study. ACTA ANATOMICA 1997; 158:112-20. [PMID: 9311420 DOI: 10.1159/000147920] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
A morphometric study was made of the number of sweat glands and hairs per square centimeter of skin on different body regions of Korean adults. For this purpose, samples of skin from 30 body regions were obtained by punch biopsy from 74 cadavers of Korean adults. Serial transverse sections that extended through the papillary layer of the dermis were prepared in each case and subjected to routine histological staining. Sections of skin were examined under low magnification and the sweat ducts and hair follicles in each section were counted and recorded in terms of the number per square centimeter of skin. Arithmetic means and standard deviations for each region were also obtained for comparison of the densities of distribution. The soles (male) and the palms (female) were the regions of most densely distributed sweat glands while the mammary area in both sexes was the region of lowest density. Hairs were distributed most densely in the buccal region in males and on the mental (chin) region in females. The region of lowest density of hairs was the dorsum of the middle phalanx of the fingers in both sexes. Seven regions of the body exhibited significant sexual dimorphism in terms of the density of sweat glands while only four regions showed significant sexual dimorphism in terms of the density of hairs. Hairs appeared to be more densely distributed in the buccal regions of females than of males. However, the density of hairs in the dermis was not always proportional to the density of visible hairs.
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117
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Abstract
The iliac bone is one of the most common donor sites for bone graft. Despite such potential and clinical usefulness, the anthropometric data on the iliac bone are lacking. The purpose of this study is to construct a thickness map that provides the mean iliac bone thickness of its various points and their differences. We studied 58 hip bones (from 23 males and 35 females) from Korean adults. We measured the iliac bone thickness at 26 points, which were positioned at regular intervals on each given iliac bone, using a Techlock GM 21 caliper gauge. The mean thickness of each measuring point of the male and the female, and of the right and the left, was compared with each other through paired t-test; the measurements did not differ significantly. From the anteriorposterior perspective, the region between anterior superior iliac spine (ASIS) and iliac tubercle was relatively thick. However, it became progressively thinner before it reached the sacroiliac articulation. It became thicker again toward the posterior superior iliac spine (PSIS), the thickest area. From the superoinferior perspective of superior iliac crest and inferior acetabulum, the thickness became inferiorly thinner in the anterior part between ASIS and iliac tuberosity. However, in the posterior part between the sacroiliac joint and PSIS, there was no significant difference of thickness. We hope that our thickness map can serve as a practical guide to the choice of an ideal site of the iliac bone for bone graft to obtain desired thickness.
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118
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Abstract
The parietal bone remains the most common donor site for a bone graft in treating facial bone fractures, especially those involving orbital walls. Despite this potential clinical usefulness, anthropometric data on the parietal bone is lacking. Only one Korean and a few foreign studies report on its thickness, measured at two and three points of each of two parietal bones in a given subject, respectively. These studies, however, fall short of offering enough information for locating the optimal harvest point of the parietal bone for bone grafting. This study was thus aimed at constructing a thickness map that provides the mean parietal bone thickness at various points and determines the difference between them. Eighty-eight parietal bones were obtained from 44 Korean adult skulls for this study. Parietal bone thickness was measured at 15 points, spaced at regular intervals on each parietal bone of a given skull, using a Techlock GM 21 caliper gauge. The mean bone thickness at each of the 15 points of the bone and at the corresponding points of the opposite parietal bone was obtained in all skulls studied. The mean thickness at each point of measurement on two opposite parietal bones was compared using the paired Student's t test. Mean thickness did not differ significantly. The thickness in the same bone varied widely depending on the points of measurement. The thickest part, the posteromedial region of the parietal bone near the lambda, was 6.67 +/- 1.41 mm (mean +/- standard deviation [SD]) thick, and it became thinner toward the diagonal (anterolateral) direction, to the thinnest part, 4.73 +/- 1.19 mm (mean +/- SD) thick, near the pterion. It is hoped that our thickness map can serve as a practical guide for choosing an ideal site on the parietal bone for a bone graft of desired thickness.
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119
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Hwang K, Milner JA. Intracellular distribution of selenium and the growth of mammary cells in culture. Biol Trace Elem Res 1996; 51:133-47. [PMID: 8907017 DOI: 10.1007/bf02785433] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Retention of Se in CMT-13 cells increased with an increase in the concentration of selenite in the incubation medium, the duration of exposure, and the density of the culture. The enhanced toxicity of selenite coincided with a proportional increase in Se in both the cytoplasm and nucleus. About 90% of the accumulated Se was isolated with cytoplasmic macromolecules. Increased nuclear Se retention correlated with increased cytoplasmic Se retention. Greater quantities of cytosolic Se-containing proteins (74, 55, 41, 34, and 28 kDa) and a nuclear Se-containing protein (56 kDa) were detected as the quantity of Se within CMT-13 cells increased. These findings suggest that cellular retention and distribution of Se are determinants of the degree of cellular growth inhibition caused by this trace element.
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120
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Zhiwei Xu, Hwang K. Modeling communication overhead: MPI and MPL performance on the IBM SP2. ACTA ACUST UNITED AC 1996. [DOI: 10.1109/88.481662] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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121
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Hwang K, Schmittmann B, Zia RK. Three-point correlation functions in uniformly and randomly driven diffusive systems. PHYSICAL REVIEW. E, STATISTICAL PHYSICS, PLASMAS, FLUIDS, AND RELATED INTERDISCIPLINARY TOPICS 1993; 48:800-809. [PMID: 9960661 DOI: 10.1103/physreve.48.800] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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122
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Abstract
Previously, a mouse hepatitis virus (MHV) genomic sequence necessary for defective interfering (DI) RNA packaging into MHV particles (packaging signal) was mapped to within a region of 1,480 nucleotides in the MHV polymerase gene by comparison of two DI RNAs. One of these, DIssF, is 3.6 kb in size and exhibits efficient packaging, whereas the other, DIssE, which is 2.3 kb, does not. For more precise mapping, a series of mutant DIssF RNAs with deletions within this 1,480-nucleotide region were constructed. After transfection of in vitro-synthesized mutant DI RNA in MHV-infected cells, the virus product was passaged several times. The efficiency of DI RNA packaging into MHV virions was then estimated by viral homologous interference activity and by analysis of intracellular virus-specific RNAs and virion RNA. The results indicated that an area of 190 nucleotides was necessary for packaging. A computer-generated secondary structural analysis of the A59 and JHM strains of MHV demonstrated that within this 190-nucleotide region a stable stem-loop of 69 nucleotides was common between the two viruses. A DIssE-derived DI DNA which had these 69 nucleotides inserted into the DIssE sequence demonstrated efficient DI RNA packaging. Site-directed mutagenic analysis showed that of these 69 nucleotides, the minimum sequence of the packaging signal was 61 nucleotides and that destruction of the secondary structure abolished packaging ability. These studies demonstrated that an MHV packaging signal was present within the 61 nucleotides, which are located on MHV genomic RNA 1,381 to 1,441 nucleotides upstream of the 3' end of gene 1.
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123
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Hwang K, Schmittmann B, Zia RK. Three-point correlations in driven diffusive systems with Ising symmetry. PHYSICAL REVIEW LETTERS 1991; 67:326-329. [PMID: 10044860 DOI: 10.1103/physrevlett.67.326] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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124
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Collins EJ, Robertus JD, LoPresti M, Stone KL, Williams KR, Wu P, Hwang K, Piatak M. Primary amino acid sequence of alpha-trichosanthin and molecular models for abrin A-chain and alpha-trichosanthin. J Biol Chem 1990; 265:8665-9. [PMID: 2341399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Ricin A-chain, abrin A-chain, and alpha-trichosanthin are members of a larger group of proteins called ribosome-inactivating proteins. These proteins all function to catalytically inactivate eukaryotic 60 S ribosomal subunits leading to rapid shutdown of protein synthesis. They are homologous in sequence and are probably evolutionarily related. We have determined the complete primary amino acid sequence of alpha-trichosanthin and have found it to be homologous, as expected, to that of abrin A-chain and ricin A-chain. A crystal structure for ricin, which includes ricin A-chain and ricin B-chain, has been determined from x-ray diffraction data. Based on the sequence homologies of these proteins, we fit the primary sequences of abrin A-chain and alpha-trichosanthin to the backbone structure for ricin A-chain and have generated energy-minimized molecular models for them. These models should prove useful in studying the structural-functional relationships of these proteins in particular and of the class in general.
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Collins EJ, Robertus JD, LoPresti M, Stone KL, Williams KR, Wu P, Hwang K, Piatak M. Primary amino acid sequence of alpha-trichosanthin and molecular models for abrin A-chain and alpha-trichosanthin. J Biol Chem 1990. [DOI: 10.1016/s0021-9258(19)38939-2] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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