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S Kim

Publications and source records attributed to S Kim.

At least 793 records · Page 44Linked to original sources
PubMed1997

[Role of the renin-angiotensin system in cardiovascular and renal diseases].

Accumulating evidence indicate that various growth-related genes, growth factors and extracellular matrix components play a central role in the pathogenesis of cardiovascular and renal diseases by regulating cellular phenotype, growth and migration or promoting tissue fibrosis. Treatment of hypertensive rats with an angiotensin II type 1-receptor (AT1-receptor) antagonist normalizes cardiac phenotypic modulation and the increased fibrosis-related gene expressions in hypertrophied heart, leading to the improvement of cardiac dysfunction. The AT1-receptor antagonist can inhibit protooncogenes (c-fos, c-jun and Egr-1) and fibronectin gene expressions in rat balloon-injured artery, which is associated with the inhibition of neointima formation. Furthermore, the AT1-receptor antagonist prevents either the phenotypic modulation of glomerular mesangial cells or the increase in transforming growth factor-beta 1 expression in nephrosclerosis. Thus, the AT1-receptor antagonist in vivo potently inhibits the expression of growth-related gene and extracellular matrix and inhibits cellular phenotypic modulation. The AT1-receptor is responsible for the pathogenesis and development of cardiovascular and renal diseases.

Angiotensin Receptor Antagonists↗
PubMed1997

Effects of angiotensin AT1 receptor antagonist on volume overload-induced cardiac gene expression in rats.

The present study was undertaken to examine the effects of volume overload on cardiac gene expression and the possible role of angiotensin AT1 receptor in such expression. Cardiac volume overload was prepared by abdominal aortocaval shunt in rats. Rats with aortocaval shunt were treated with 1) vehicle, 2) an angiotensin AT1 receptor antagonist, CS-866 (10 mg/kg/d), or 3) an angiotensin-converting enzyme inhibitor, temocapril (10 mg/kg/d), for 7 days. Cardiac tissue mRNA was measured by Northern blot analysis with specific probes. Aortocaval shunt not only caused cardiac hypertrophy but also upregulated the gene expression of atrial natriuretic polypeptide, collagen III, and downregulated Ca(2+)-ATPase expression in the left ventricle. These changes were prevented by treatment with CS-866, while temocapril failed to normalize left ventricular Ca(2+)-ATPase expression. Unlike the left ventricle, the significant downregulation of alpha-myosin heavy chain and transforming growth factor-beta 3 by aortocaval shunt was observed in the right ventricle, and CS-866 normalized this decreased expression of transforming growth factor-beta 3. The left and right atria showed increased expression of collagen type I as well as of collagen type III and atrial natriuretic polypeptide, and these increases were more effectively prevented by CS-866 than by temocapril. Thus, the effects of cardiac volume overload on cardiac performance-related gene expression differ between the ventricles and atria. Our results suggest that AT1 receptor partially contributed to volume overload-induced changes in cardiac gene expression and that AT1 receptor antagonists and angiotensin-converting enzyme inhibitors have different effects in this model of cardiac hypertrophy.

Actins↗
PubMed1997

Analysis of tube thoracostomy performed by pulmonologists at a teaching hospital.

STUDY OBJECTIVE: To evaluate all tube thoracostomies (TTs) done by pulmonary/critical care fellows and attending physicians in the Medical University of South Carolina's health-care system documenting patient demographics, indication for placement, size and characteristics of the tube, and associated problems. DESIGN: Prospective. SETTING: University health-care system, including a university hospital, a Veterans Affairs hospital, and a county hospital. PATIENTS: All adult patients requiring consultation by a member of the pulmonary/critical care staff for a tube thoracostomy. RESULTS: One hundred twenty-six tube thoracostomies were performed over a 24-month period in 91 patients. The most common initial indication for a TT was pneumothorax (69/103, 67%). Overall mortality in the patient population was 35% (32/91). Early problems (< 24 hours following placement) occurred in 3% (4/126); late problems (> 24 h after placement) occurred in 8% (10/126). Problems occurred in 36% (4/11) of small-bore tube placements vs 9% (10/115) of standard TT placements (p=0.02). CONCLUSIONS: Tube thoracostomy can be safely performed by pulmonologists with relatively few associated problems.

Adolescent↗
PubMed1997

Mechanisms of edema formation after intracerebral hemorrhage: effects of thrombin on cerebral blood flow, blood-brain barrier permeability, and cell survival in a rat model.

Recently, the authors showed that thrombin contributes to the formation of brain edema following intracerebral hemorrhage. The current study examines whether the action of thrombin is due to an effect on cerebral blood flow (CBF), vasoreactivity, blood-brain barrier (BBB) function, or cell viability. In vivo solutions of thrombin were infused stereotactically into the right basal ganglia of rats. The animals were sacrificed 24 hours later; CBF and BBB permeability were measured. The actions of thrombin on vasoreactivity were examined in vitro by superfusing thrombin on cortical brain slices while monitoring microvessel diameter with videomicroscopy. In separate experiments C6 glioma cells were exposed to various concentrations of thrombin, and lactate dehydrogenase release, a marker of cell death, was measured. The results indicate that thrombin induces BBB disruption as well as death of parenchymal cells, whereas CBF and vasoreactivity are not altered. The authors conclude that cell toxicity and BBB disruption by thrombin are triggering mechanisms for the edema formation that follows intracerebral hemorrhage.

Animals↗
PubMed1997

Idiopathic retroperitoneal fibrosis presented as an abdominal mass and nephrotic syndrome.

We present a 30-year-old male patient who was initially diagnosed as minimal change nephrotic syndrome, 5 years later, the patient developed a localized form of idiopathic retroperitoneal fibrosis (IRF). An elevated ESR and concomitant nephrotic syndrome in the patient suggested the immunologic nature of IRF, IRF has been reported in association with collagen diseases and rarely with proliferative and nonproliferative glomerulopathies. To our knowledge, the association between minimal change lesion (MC) and IRF has not been reported. Furthermore, the fact that IRF presented itself as an abdominal mass and lacked systemic symptoms was also unusual.

Adult↗
PubMed1997

Learning from other lands. Caring for elderly demented Koreans.

The aims of the study reported here were to describe the socio-demographic characteristics of caregivers of demented elders in Korea and their care recipients and to compare the positive and negative meanings and outcomes of the caregiving experiences of caregivers who had admitted their elderly demented relative to a nursing home (G1: n = 24) and caregivers still caring for their elderly demented relatives at home (G2: n = 30). Most caregivers were female (80%), married (89%), and related to the care receiver as daughter-in-law (39%), daughter (22%), wife (15%), son (13%), or neighbor (6%). Social class differences were found between the home care and nursing home groups: the upper classes were significantly more likely to have placed their demented elder in a nursing home, whereas the low social classes were more likely to keep taking care of their demented elder at home instead of placing them in a nursing home. Caregivers who had admitted their relative to a nursing home (G1) reported significantly more difficulties from disturbed sleep, disrupted children's studies, and limited personal life when they were caring for the elder at home (p < .05). Caregivers in the home care group (G2) had significantly greater satisfaction in serving as a model for their children and practicing religion (p < .05), and they also reported a better relationship with the care receiver than those who have placed their demented elder in a nursing home, although the difference in this case was not significant.

Adult↗
PubMed1997

Chronic infection with Toxoplasma gondii does not prevent acute disease or colonization of the brain with tissue cysts following reinfection with different strains of the parasite.

Two strains of Toxoplasma gondii with different capacities to induce disease and brain lesions in mice were used to study the effects of reinfection with the parasite on a previously infected host. In spite of marked antibody and cell-mediated immune responses, chronically infected mice developed disease and died of acute toxoplasmosis when reinfected with a strain different from the one causing the primary infection. Moreover, the marked antibody and cell-mediated immune responses of the chronically infected mice did not prevent invasion of their brains and formation of tissue cysts by the reinfecting strain. Tissue cysts of the reinfecting strain were demonstrated in the brains of the chronically infected and subsequently reinfected mice. These results highlight the importance of strain differences in the pathogenesis of toxoplasmosis.

Acute Disease↗
PubMed1997

The effect of a brief education program on glaucoma patients.

PURPOSE: To assess our patients' knowledge of glaucoma and to measure the effect of a brief education program on their understanding of glaucoma. METHODS: Patients attending glaucoma clinics at a university and a Veterans' Affairs hospital were randomized into two groups: "exposed" and "unexposed" to a simple education program of a video and brochures. Glaucoma knowledge was assessed twice by an oral questionnaire, at 2 weeks and 6 months after randomization plus or minus education. RESULTS: Younger patients and those with more years of formal schooling knew more about glaucoma. Two weeks after the education program, the exposed group performed significantly better than did the unexposed group. Analysis of the results showed benefit from both brochures and video. This effect of education was not seen at retesting 6 months later. CONCLUSION: Older patients and those with less formal education know less about glaucoma. A brief, simple education program can significantly improve levels of knowledge about glaucoma, even in a relatively well-informed population. However, patient education must be repeated to maintain a useful effect.

Aged↗
PubMed1997

Principles of endodontic microsurgery.

With bright illumination and magnification under the operating microscope, and addition of many microinstruments, endodontic surgery has become microsurgery. The microsurgical approaches allow the clinicians to perform endodontic surgery with smaller osteotomies, shallow bevels, preparation of isthmuses, examination of resected root surfaces, retropreparation in line with root canal, and precise placement of new filling materials. This article illustrates the advantages of microsurgery in endodontics.

Alveolectomy↗
PubMed1997

Hemostasis in endodontic microsurgery.

There are numerous ways to achieve hemostasis. With the abundance of hemostatic agents available and with the introduction of new products, one has to make an objective decision. A good agent achieves hemostasis within a short period of time, is easy to manipulate, is biocompatible, does not impair or retard healing, must be relatively inexpensive, is reliable, and works best for the particular surgical procedure. With these purposes in mind, the following sequence is recommended to achieve hemostasis during endodontic microsurgery. I. Presurgical: Give 2 to 3 Carpules of 1:50,000 epinephrine local anesthetic with multiple infiltration sites throughout the entire surgical field. II. Surgical: A. Remove all granulation tissue. B. Place an epinephrine pellet into the bony crypt followed by dry sterile cotton pellets. Apply pressure for 2 minutes. Remove all the cotton pellets except the first epinephrine pellet. Continue with the surgical procedure and remove the epinephrine pellet before final irrigation and closure. C. Alternatively, calcium sulfate can be mixed into a thick putty and packed against the bone cavity. Because it is a biodegradable material, calcium sulfate can be left in situ. In fact, in large bone defects and through-and-through lesions, additional calcium sulfate can be placed to fill the entire bone cavity as a barrier material. Healing is more predictable with little chance of scar tissue formation. Calcium sulfate resorbs in 2 to 4 weeks. D. Small bleeding sites in the bone can be brushed with ferric sulfate solution. III. Postsurgical: Tissue compression before and after suturing cuts down on postsurgical bleeding and swelling. Hemostasis is imperative in endodontic microsurgery for better visualization, a good environment for placement of retrograde filling material, and a more efficient surgical procedure with less blood loss.

Alveolectomy↗
PubMed1997

The resected root surface. The issue of canal isthmuses.

Incomplete debridement of the canal isthmus is responsible for some surgical and nonsurgical endodontic failures. This article reviews the formation of canals isthmus and the new classification system. Recent research findings regarding the incidence of isthmus at different root end levels are included.

Apicoectomy↗
PubMed1997

Barrier membrane techniques in endodontic microsurgery.

The ultimate goal in endodontic microsurgery is the predictable regeneration of periapical tissues. One of the main concerns in treating an endodontically treated tooth which has a through-and-through osseous defect is that incomplete bone healing may be inevitable. This article reviews the use of different barrier membranes for bone regeneration. In addition, the indications, techniques, and prognosis of calcium sulfate in guided bone regeneration are presented.

Alveolectomy↗
PubMed1997

Loss of heterozygosity at chromosome segment Xq25-26.1 in advanced human ovarian carcinomas.

To determine whether a tumor suppressor gene of importance to epithelial ovarian cancer resides on the X chromosome, we examined loss of heterozygosity (LOH) in 123 epithelial ovarian cancer cases. In 54 such cases, we examined LOH at 26 loci on the human X chromosome. In eight cases, we examined LOH in 14 loci and in 61 cases we examined LOH in 13 loci. Matched DNA samples from tumors and corresponding normal tissues were analyzed by polymerase chain reaction (PCR) amplification of microsatellite markers. Frequent losses were found in epithelial carcinomas at the Xq25-26.l region, including DXS1206 (34.5% loss in informative cases), DXS1047 (27.7%), HPRT (24.1%), and DXS1062 (33.3%). The minimum overlapping region of LOH was approximately 5 megabases (Mb), flanked by DXS1206 (Xq25) and HPRT (Xq26.1). The methylation status of the remaining allele of the androgen receptor gene in the tumors exhibiting LOH at the Xq25-26.1 region suggested that the loss was exclusively in the inactive X chromosome. We next determined whether a significant relationship exists between Xq LOH and other parameters, including histologic grade and/or clinical stage of the tumors and LOH at TP53. The Xq LOH had a significant association with grade 2 to 3 tumors at stages II to IV. Sixteen of 18 cases that showed Xq LOH revealed LOH at the TP53 locus, and 45% of tumors exhibiting LOH at TP53 showed Xq LOH. These results suggest that there may be a tumor suppressor gene or genes which escape inactivation of the X chromosome at Xq25-26.1, and that the loss of the gene(s) at Xq25-26.1 is frequently accompanied by loss of the TP53 or loss of another gene on chromosome 17. These losses may contribute to the progression from a well-differentiated to a more poorly differentiated state or to metastatic aggressiveness.

Carcinoma↗
PubMed1997

Longer occupancy of opioid receptors by nalmefene compared to naloxone as measured in vivo by a dual-detector system.

UNLABELLED: Surgical procedures usually involve the administration of narcotic drugs as anesthetics or adjuvants. To reverse the effects of anesthesia, opioid antagonists such as naloxone are commonly used. Due to its short lasting effects, patients receiving naloxone must be monitored carefully. Nalmefene, a pure opiate antagonist with a longer duration of action than naloxone, has shown promise in the reversal of opioid anesthesia. METHODS: A simple dual-detector positron radiation detector system and [11C]carfentanil were used to compare the duration of blockade of cerebral mu opioid receptors by naloxone and nalmefene in eight normal volunteers. Carbon-11-carfentanil brain kinetics were monitored for 5 min and 2, 4, 8 and 24 hr after the administration of either nalmefene (1 mg or 1 microg/kg) or naloxone (2 mg or 2 microg/kg). Blood samples were obtained at the same times for plasma determinations. RESULTS: Clearance half-times from opioid receptors were 28.7 +/- 5.9 hr for 1 mg of nalmefene and 2.0 +/- 1.6 hr for 2 mg of naloxone. Brain clearance times were about 21.1 and 3.4 times slower than plasma clearance times for nalmefene and naloxone, respectively. CONCLUSION: These findings suggest that the prolonged effects of nalmefene are related to the slow dissociation of nalmefene from opioid receptors, which are not reflected in the plasma curve. This longer blockade of opioid receptors by nalmefene represents an advantage in the clinical management of postsurgical reversal of narcotic anesthesia and opioid side effects as well as the reversal of opioid overdose.

Adult↗
PubMed1997

Lymphocyte recruitment and the kinetics of adhesion receptor expression during the pulmonary immune response to particulate antigen.

The selectins and beta2 integrins participate in the recruitment of neutrophils in acute pulmonary inflammation. However, the cell adhesion receptors that mediate lymphocyte trafficking into the lung have not been defined. This study examined the relationship between cell adhesion molecules on the pulmonary vasculature and on lymphocytes recovered from the lung during a pulmonary immune response to intratracheal (I.T.) sheep red blood cells (SRBCs) in sensitized C57BL/6J mice. Silver-enhanced immunogold staining and reverse transcriptase polymerase chain reaction of lung tissues revealed sustained induction of VCAM-1, E-selectin, and P-selectin on the pulmonary vasculature for up to 7 days after I.T.-SRBC challenge. Neither the MECA 79 nor MECA 367 antigens were induced on the pulmonary vasculature during this period. In the peripheral blood, both CD4 and CD8 T-cell subsets showed an initial increase in P-selectin ligand expression after I.T.-SRBC challenge. The number of P-selectin ligand-positive T cells in the peripheral blood fell as T cells with both P-selectin and, to a lesser extent, E-selectin ligands accumulated in the bronchoalveolar lavage fluid. We conclude that I.T.-SRBC challenge in sensitized mice elicits prolonged synthesis of P-selectin, E-selectin, and VCAM-1 by the lung vasculature as well as selectin ligand synthesis by responding T cells. Furthermore, the entry of selectin-ligand-positive T cells into the circulation and their accumulation in the bronchoalveolar lavage fluid indicates that these receptors may contribute to T cell recruitment. Finally, VCAM-1 on the vasculature may also participate; however, the vascular addressins, required for homing to peripheral and mucosal lymphoid organs, are not essential for T-cell entry into the lung following I.T.-SRBC challenge.

Animals↗
PubMed1997

Involvement of angiotensin II in cardiovascular and renal injury: effects of an AT1-receptor antagonist on gene expression and the cellular phenotype.

OBJECTIVES: We investigated the effects of an angiotensin II type 1 (AT1)-receptor antagonist on experimental cardiac hypertrophy, vascular thickening and nephrosclerosis, in order to determine the involvement of this receptor in the development of cardiovascular and renal damage. DESIGN: Accumulating evidence indicates that various growth-related genes, growth factors and extracellular matrix components play a central part in the pathogenesis and development of cardiovascular and renal diseases, either by regulating cell growth and migration or by promoting tissue fibrosis. MATERIALS AND METHODS: Stroke-prone spontaneously hypertensive rats were given candesartan cilexetil, a specific non-peptide AT1-receptor antagonist, for 10 weeks, and cardiac phenotypic and fibrosis-related gene expression and aortic and mesenteric arterial gene expressions were determined. Balloon-injured carotid arteries and deoxycorticosterone acetate (DOCA)-salt hypertensive rats were also similarly examined. RESULTS: Treatment of hypertensive rats with an AT1-receptor antagonist led to the regression of cardiac hypertrophy, suppression of cardiac phenotypic changes to a fetal phenotype and an increase in fibrosis-related gene expression in the hypertrophied heart. Balloon injury-induced neointima formation in the rat carotid artery was prevented by the AT1-receptor antagonist, which was associated with the inhibition of the induction of proto-oncogenes such as c-fos, c-jun and Egr-1 and of increased fibronectin gene expression. Furthermore, the AT1-receptor antagonist prevented either the phenotypic modulation of glomerular cells or an increase in transforming growth factor-beta 1 expression in an experimental model of nephrosclerosis. CONCLUSIONS: AT1-receptor antagonists in vivo potently inhibit the expression of the growth-related and extracellular matrix genes, as well as cellular phenotypic modulation. These molecular effects of the AT1-receptor antagonist may contribute to their protective effects on cardiovascular and renal diseases.

Angiotensin II↗