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S J Shin

Publications and source records attributed to S J Shin.

At least 73 records · Page 4Linked to original sources

Increased nitric oxide synthase mRNA expression in the renal medulla of water-deprived rats.

UNLABELLED: Increased nitric oxide synthase mRNA expression in the renal medulla of water-deprived rats. BACKGROUND: Experiments were performed to investigate whether renal nitric oxide synthase (NOS) mRNA and protein expression are responsive to the alteration of body volume. METHODS: Four days of water deprivation (WD) was initiated in 16 male Wistar rats, and 16 normal rats (NC) served as the control group. Neuronal NOS (nNOS), endothelial NOS (eNOS), and inducible NOS (iNOS) mRNAs and immunoreactivity were measured by reverse transcription-polymerase chain reaction (RT-PCR) followed by Southern blot hybridization and immunohistochemistry, respectively. Plasma angiotensin II, vasopressin, and atrial natriuretic peptide (ANP) concentrations were measured by radioimmunoassay. RESULTS: The four-day WD increased plasma sodium and osmolality levels, but severely decreased daily urine sodium excretion and urine volume. Plasma angiotensin II and vasopressin concentrations were increased, but the plasma ANP level was significantly decreased in WD rats. nNOS, eNOS, and iNOS mRNA levels were increased by 5.2-, 3.3-, and 3. 4-fold in the outer medulla and 1.7-, 1.5-, and 1.8-fold in the inner medulla, whereas no significant difference was found in the renal cortex of WD rats as compared with NC rats. Additionally, immunohistochemistry revealed that the immunostaining intensity of nNOS, eNOS, and iNOS was clearly enhanced in the medullary thick ascending limb, proximal straight tubule, inner medullary collecting duct, and proximal convoluted tubule in WD rats. Kidney angiotensin II content as well as renin mRNA levels in renal cortex, outer medulla, and inner medulla in WD rats were apparently increased. CONCLUSIONS: Our results indicate that the increases of nNOS, eNOS, and iNOS synthesis in the kidney, particularly in the renal medulla, may have a role in the adaptation of renal function to volume depletion in the face of an increase of systemic and intrarenal vasoconstrictive substances.

Angiotensin II↗

Salmonella enterica serotype Dublin infection: an emerging infectious disease for the northeastern United States.

Salmonella enterica subspecies enterica serotype Dublin (S. enterica Dublin) emerged for the first time in New York, Pennsylvania, and Ohio in 1988. Since that time this host-adapted serotype has spread throughout the veal- and dairy beef-raising operations in the region; very few dairy farms have experienced clinical S. enterica Dublin infections. This study details the epidemiology of the outbreaks in cattle. During the period 1988 through 1995, nine New York and four Pennsylvania counties have been affected; 13 different locations were involved in New York, and 10 were involved in Pennsylvania. The morbidity and mortality and seasonal distribution of outbreaks, which totaled 35, is described. The antimicrobial susceptibility pattern of isolates revealed that many of the strains were resistant to a number of commonly used drugs. Clinical case details and pathology information are provided, with a caution to clinicians and microbiologists presented with suspect animals, i.e., most cases occurred in older calves, which is atypical for salmonellosis for this region (calves were 8 or more weeks old) and presented as pneumonia and septicemia rather than the primarily diarrheal syndrome that is more typically recognized for the region. The epidemiology of cases is analyzed through cluster analysis of bacterial isolates and their fatty acid methyl ester profiles; at least six clones appeared in the region during the study period. Results of the epidemiology analysis are used to support a hypothesis regarding the source of S. enterica Dublin for the region and its manner of dissemination.

Animals↗

Increased urinary atrial natriuretic peptide-like immunoreactivity excretion but decreased plasma atrial natriuretic peptide concentration in patients with hyperosmolar-hyperglycemic nonketotic syndrome.

OBJECTIVE: This study was undertaken to measure urinary atrial natriuretic peptide-like immunoreactivity (ANP-LI) and plasma ANP concentration in patients with hyperosmolar-hyperglycemic nonketotic syndrome (HHNS) to investigate the change of renal ANP-LI and cardiac ANP synthesis in volume-depleted diabetic patients. RESEARCH DESIGN AND METHODS: The urine ANP-LI:creatinine ratio, plasma ANP level, and plasma renin activity (PRA) were measured in 12 patients with HHNS during the acute stage and after recovery, in 28 oral hypoglycemic agent (OHA)-treated type 2 diabetic patients, and in 23 normal subjects. ANP and PRA were measured by radioimmunoassay. RESULTS: These HHNS patients had severe hyperglycemia and hyperosmolality as well as increased blood urea nitrogen, creatinine, and PRA levels, as compared with normal subjects and OHA-treated type 2 diabetic patients. In these patients, the urinary ANP-LI:creatinine ratio (11.69 +/- 2.11 pmol/mmol) was significantly increased in comparison with the normal group (1.78 +/- 0.11 pmol/mmol) and OHA-treated diabetic patients (2.43 +/- 0.45 pmol/mmol), whereas plasma ANP concentration (5.12 +/- 0.72 pmol/l) was significantly lower than the corresponding values of the normal group (7.39 +/- 0.85 pmol/l) and OHA-treated diabetic patients (8.43 +/- 1.05 pmol/l). All of these abnormalities were significantly ameliorated after insulin, fluid, and electrolyte replacement. CONCLUSIONS: Our data show that urinary ANP-LI was significantly increased, whereas plasma ANP concentration was decreased, in the face of raised PRA in HHNS patients. This study indicates that renal ANP-LI substances and cardiac ANP may exhibit different responsiveness in diabetic patients with HHNS.

Analysis of Variance↗

The role of radiotherapy in the treatment of aggressive fibromatosis.

Aggressive fibromatosis is a rare benign soft tissue tumor that is difficult to cure because of its infiltrative nature and high tendency to recur locally. The authors retrospectively analyzed 20 patients with histologically-confirmed fibromatosis. All patients underwent surgery with a wide or marginal margin. Five (25%) cases with histologically-negative margins had recurred. External beam radiotherapy was administered to patients whose margins were positive or who had local recurrence. However, out of concern for safety, radiotherapy was not given to two babies and a reproductive-aged woman. The average dose was 5,020 cGy. During the follow-up (mean 32.6 months), all the patients undergoing radiotherapy showed no evidence of local recurrence. A wide local excision has traditionally been the treatment of choice. However, postoperative radiotherapy could be an effective measure for preventing local recurrence in patients with a histologically-positive surgical margin and recurrence independent of any signs of relapse.

Adolescent↗

Technical evolution of arthroscopic knee surgery.

The widespread growth of arthroscopic techniques and their use has dramatically changed the practice of orthopaedic surgery. A high degree of clinical accuracy and minimally invasive procedure with a low surgical morbidity have encouraged the use of arthroscopy to assist in diagnosis, to determine prognosis and to provide treatment. In particular, the knee is the proper joint in which arthroscopy has its diagnostic and intraarticular surgical application. The rapid advancement of arthroscopic techniques has demonstrated a variety of surgical techniques in procedures such as meniscectomy, meniscal repair and cruciate ligament reconstruction during the last decade. This article reviews the past history of arthroscopy and technical evolution of arthroscopy in knee surgery in our department.

Anterior Cruciate Ligament↗

Ovarian teratomas appearing as solid masses on ultrasonography.

The purposes of this study were to evaluate the prevalence and imaging characteristics of ovarian teratomas that appear as solid masses on ultrasonography and to compare the ultrasonographic imaging features of the tumors with their pathologic findings. The ultrasonographic images of 202 ovarian teratomas were reviewed retrospectively. Solid-appearing masses were selected from among them and were evaluated in terms of internal echotexture, the presence or lack of peripheral hypoechogenicity, posterior sonic attenuation, and tumoral calcification. Seventy-six (37.6%) masses of 202 belonged to the atypical solid-appearing masses on ultrasonography. Of 76 masses, 57 (75.0%) had peripheral hypoechogenicity; 38 masses had well-defined thin hypoechoic rims, whereas 19 had poorly demarcated peripheral hypoechogenicity. Posterior sonic attenuation was evident in 18 (23.7%) masses. The presence of peripheral hypoechogenicity, which is suggestive of the fluid portion of the tumor, might be one of the characteristic findings of solid-appearing ovarian teratomas on ultrasonography.

Adolescent↗

Increased urinary endothelin-1 excretion in newly diagnosed type 2 diabetic patients.

To investigate whether urinary and plasma endothelin (ET)-1 concentrations are responsive to the alteration of intravascular blood volume in uncontrolled diabetic patients, we determined urinary ET-1 excretion and plasma ET-1 concentration in 42 newly diagnosed type 2 diabetic patients and 38 normal subjects. Mean fasting plasma glucose value (12.8 +/- 0.72 mmol l-1) and plasma renin activity (PRA, 2.80 +/- 0.44 ng ml-1 hr-1) in diabetic patients were significantly higher as compared to normal controls (mean plasma glucose value: 5.2 +/- 0.83 mmol l-1; mean PRA value: 1.34 +/- 0.17 ng ml-1 hr-1), whereas plasma ET-1 value (1.33 +/- 0.07 pmol l-1) was not significantly different from that (1.29 +/- 0.06 pmol l-1) of normal controls. Mean urinary ET-1 excretion level (7.53 +/- 0.74 nmol mol-1 creatinine) was significantly higher than that (5.36 +/- 0.37 nmol mol-1 creatinine) of normal controls. Urinary ET-1 excretion was correlated with plasma glucose value (r = 0.360, p < 0.05) and PRA value (r = 0.381, p < 0.05). Urinary ET-1 excretion rate (5.17 +/- 0.37 nmol mol-1 creatinine) and PRA value (1.42 +/- 0.18 ng ml-1 hr-1) declined to normal levels when mean plasma glucose value decreased to the level of 7.1 +/- 0.39 mmol l-1 in diabetic patients after 4 months of glycemic control. Our results indicated that renal-derived ET-1 was responsive to the alteration of intravascular blood volume in untreated newly diagnosed type 2 diabetic patients.

Aged↗

Increased renal ANP synthesis, but decreased or unchanged cardiac ANP synthesis in water-deprived and salt-restricted rats.

BACKGROUND: Experiments were performed to examine the effect of water deprivation and salt restriction on ANP synthesis in the kidneys and hearts of normal rats. METHODS: A 4-day water deprivation (WD) and 7-day salt restriction (SR; 0.01% NaCl) were performed in 12 and 14 rats, respectively. Atrial natriuretic peptide (ANP) mRNA expression in the kidney was assessed with reverse transcription-polymerase chain reaction coupled with Southern blot hybridization, while the ANP mRNA in the hearts was measured by Northern blot hybridization. ANP and angiotensin II concentrations in the extracted plasma were measured by radioimmunoassay. The molecular form of renal ANP-like protein was characterized by reverse phase-high-performance liquid chromatography (RP-HPLC). RESULTS: Renal outer and inner medullary ANP mRNA showed a respective 11-fold and ninefold increase in WD rats, and an eightfold and fivefold increase in SR rats as compared to corresponding control groups. Inversely, cardiac atrial ANP mRNA and plasma ANP were decreased in WD rats, whereas they did not change in the SR group. Plasma angiotensin II concentration increased in conjunction with the decrease of urine sodium excretion in both groups. RP-HPLC analysis revealed a 45% extraction of ANP in the WD rat kidneys, whereas only 3% ANP in the control kidneys migrated in a molecular form similar to cardiac atrial proANP. CONCLUSIONS: Our results demonstrate that water deprivation and salt restriction markedly enhance renal ANP mRNA, whereas water deprivation suppresses cardiac atrial ANP mRNA and plasma ANP concentrations. The current study indicates that renal ANP and cardiac atrial ANP appear to be two distinct systems regulated by different mechanisms and possibly exhibiting different intra-renal paracrine and systemic endocrine functions.

Actins↗

Interpretations of antibody responses to Salmonella enterica serotype enteritidis gm flagellin in poultry flocks are enhanced by a kinetics-based enzyme-linked immunosorbent assay.

Many regulatory and diagnostic programs for the detection of Salmonella enterica serotype Enteritidis infection in commercial poultry flocks have relied on rapid Pullorum agglutination tests to screen birds because of the shared antigens of S. enterica Enteritidis and S. enterica Pullorum and Gallinarum; however, the use of the enzyme-linked immunosorbent assay (ELISA) format affords better analytical sensitivity than crude agglutination tests. In this study, we adapted our earlier conventional indirect ELISA, using gm flagellin as the antigen, to a kinetics-based, computer-controlled ELISA (KELA). The KELA was used to screen for flagellin antibody from three commercial flocks: (i) a large flock involved in a U.S. Department of Agriculture trace back from a human S. enterica Enteritidis foodborne outbreak (n = 3,209), (ii) a flock infected with the endemic S. enterica Enteritidis serotype but which also had multiple other Salmonella serotypes (n = 65), and (iii) an S. enterica Pullorum-infected flock (n = 12). The first flock (S. enterica Enteritidis prevalence of 2.45% based on culture) provided a field test of the KELA and allowed the calculation of diagnostic sensitivity (D-Sn) and diagnostic specificity (D-Sp). With a cutoff of 10 (used for screening flocks [i.e., high sensitivity]), the KELA has a D-Sn of 95.2% and a D-Sp of 18.5%; with a cutoff of 140 (used in confirmatory flock testing [i.e., high specificity]), the KELA has a D-Sn of 28.0% and a D-Sp of 99.1%. We found that with a cutoff of 60 (D-Sn = 63.1%; D-Sp = 91.6%), we could eliminate reactions in the KELA caused by other non-S. enterica Enteritidis salmonellae. The KELA was also compared to two commercial rapid Pullorum tests, the Solvay (D-Sn = 94.9%; D-Sp = 55.5%) and the Vineland (D-Sn = 62.0%; D-Sp = 75.3%).

Animals↗

Detection of human granulocytic ehrlichiosis agent and Borrelia burgdorferi in ticks by polymerase chain reaction.

Adult ixodid ticks were collected from Westchester County, New York, and Ipswich, Massachusetts, to determine the presence of infection with a human granulocytic ehrlichiosis (HGE) agent by using the polymerase chain reaction (PCR). The presence of Borrelia burgdorferi in ticks collected from New York was also determined by PCR. Of the 229 ticks from New York and 47 ticks from Massachusetts, 9% (22/229) and 25% (12/47) of ticks contained HGE agent, respectively. Fifty-four percent (123/229) of the ticks collected from New York were B. burgdorferi positive; 4% (9/229) of these ticks contained both HGE agent and B. burgdorferi. This finding indicates that animals with Lyme borreliosis may be also exposed to the etiologic agent of HGE. More extensive laboratory diagnosis may be necessary when multiple tick-borne diseases are suspected in animals.

Animals↗

Increased C-type natriuretic peptide mRNA expression in the kidney of diabetic rats.

To investigate the responsiveness of renal-synthesized C-type natriuretic peptide (CNP) to changes in water and electrolyte balance, we measured renal CNP mRNA levels, plasma CNP concentrations and urinary CNP excretion rates in streptozotocin-induced diabetic rats eating a normal (0.26% NaCl) or low (0.04% NaCl) salt diet. Using reverse transcription-PCR followed by Southern blot analysis, we found that renal cortical and medullary CNP mRNA levels were markedly enhanced in diabetic rats from the 14th day and remained enhanced with an accompanying elevation of urinary CNP excretion rates for the entire 60-day study period. All increases of renal CNP mRNA and urinary CNP excretion rates in diabetic rats were attenuated in low salt diet-treated diabetic rats as well as insulin-treated diabetic rats. These results demonstrate that renal CNP synthesis is enhanced in diabetic rats and the increase of renal CNP mRNA is ameliorated by salt restriction and insulin treatment. These results imply that renal-synthesized CNP is responsive to the alteration of water and electrolyte homeostasis in diabetic rats.

Animals↗

Photoaffinity labeling of the ATP transporter of rat liver microsomes.

A photoreactive azido derivative of ATP, 3 (2')-O-(p-azidobenzoyl)-ATP (AB-ATP), was synthesized by the reaction of ATP with N-hydroxysuccinimidyl-4-azidobenzoate (NHS-AB) to photolabel the ATP transporter of rat liver microsomes. AB-ATP specifically inhibited the transport of ATP into microsomes, which indicates that AB-ATP has a high affinity for the ATP transporter, so it can be utilized as a photoaffinity probe for the identification of the ATP transporter in rat liver microsomes. An SDS-polyacrylamide gel electrophoresis (SDS-PAGE) analysis of microsomes photolabeled with [gamma-32P]AB-ATP indicates the presence of four major protein bands with apparent molecular sizes of 97, 56, 53, and 47 kDa. Among these labeled proteins, the 56 kDa protein was completely protected from the photoaffinity labeling by 30 microM ATP but not by the same amount of GTP, which is consistent with the specific labeling of the ATP binding site of the ATP transporter. The specific labeling of the only 56 kDa protein among them was sensitive to the anion transport inhibitor, 4,4'-diisothiocyano-2,2'-disulfonic acid stilbene (DIDS) but not sensitive to the mitochondrial ADP/ATP carrier inhibitor, atractyloside (ATR). Moreover, the 56 kDa protein was uniquely photolabeled with [gamma-32P]AB-ATP in the highly purified rough endoplasmic reticulum (RER) vesicles. These results strongly suggested that the 56 kDa protein represents the ATP transporter of rat liver endoplasmic reticulum (ER).

ATP-Binding Cassette Transporters↗

Oxidized low-density lipoprotein stimulates endothelin-1 release and mRNA expression from rat mesangial cells.

Evidence indicates that the glomerular injuries and renal hemodynamic abnormalities in hyperlipidemia are caused by the interaction of low-density lipoprotein (LDL) and oxidized LDL (Ox-LDL) with mesangial cells. Experiments were designed to investigate whether the synthesis of mesangial cell endothelin-1 (ET-1), a potent renal vasoconstrictor and mitogen for mesangial cells, is modulated by LDL and Ox-LDL. Using competitive semi-quantitative reverse transcription polymerase chain reaction (PCR), we report that the expression of cultured rat mesangial cell ET-1 mRNA was increased after treatment with Ox-LDL but not native LDL. Ox-LDL stimulated the release of ET-1 peptide into the culture medium in a time- and concentration-dependent manner. The maximal effect was observed at a concentration of 100 microg/ml, and a higher dose of Ox-LDL was found to be cytotoxic to the mesangial cells. Our results suggest that ET-1 released by Ox-LDL stimulation may be an important pathogenetic factor contributing to the renal hemodynamic alterations and progressive chronic renal diseases induced by hypercholesterolemia.

Animals↗

Increased atrial natriuretic peptide mRNA expression in the kidney of diabetic rats.

To investigate whether renal synthesis of atrial natriuretic peptide (ANP) is influenced in diabetes, we measured renal ANP mRNA levels, urine volume, urinary ANP and sodium excretion rates in streptozotocin (STZ)-induced diabetic rats. By using reverse transcription-polymerase chain reaction (RT-PCR) followed by Southern blot analysis, we found that renal cortical and outer medullary ANP mRNA levels in untreated diabetic rats were markedly increased as early as the second day after the onset of hyperglycemia and remained elevated for the entire 42-day study period. Plasma ANP concentrations in untreated diabetic rats were increased on the 42nd day, whereas plasma renin activity were suppressed. The urine volume, urinary ANP and sodium excretion rates in untreated diabetic rats were also significantly elevated on the second day and remained elevated for the entire 42-day study period. Urinary ANP excretion rates were well correlated with urine volume, and urinary sodium excretion rate in normal rats and diabetic rats on days 2, 4, 7, 14 and 42. Our results indicate that renal ANP mRNA expression is enhanced in diabetic rats, and that renal-synthesized ANP as one of regulators to handle water and sodium balance in diabetic rats is worthy of further investigation.

Animals↗

Relationships between beta-cell function and diabetic duration and albuminuria in type 2 diabetes mellitus.

To clarify whether beta-cell function deteriorates with increasing albuminuria and duration of diabetes, we investigated the insulin and c-peptide response to oral glucose tolerance test in 47 healthy subjects and 75 normoalbuminuric (group 1), 30 microalbuminuric (group 2), and 35 macroalbuminuric (group 3) Type 2 diabetes mellitus patients. The total area under the insulin curve (AUCI) values of groups 1, 2, and 3 were 245 +/- 16, 193 +/- 17, and 88 +/- 8 pmol/L.h, respectively, significantly lower than that (624 +/- 34 pmol/L.h) of the healthy group. The mean total area under the c-peptide curve (AUCC-P) values of groups 1, 2, and 3, respectively, were 2.50 +/- 0.11, 2.05 +/- 0.15, and 1.73 +/- 0.07 nmol/L.h, respectively, significantly lower than that (5.47 +/- 0.19 nmol/L.h) of the healthy controls. The mean AUCI and AUCC-P values of group 3 were significantly reduced compared to those of group 1. The mean AUCI and AUCC-P values of patients with 0-5, 5-10, 10-15, and > 15 years' duration were significantly decreased compared to those of healthy subjects. The mean AUCI and AUCC-P values of patients with > 15 years' duration were significantly lower than those of patients with 0-5 years' duration. The mean hemoglobin Alc values of the three diabetic groups were not significantly different. These data suggest that beta-cell function deterioration was associated with increasing albuminuria and diabetic duration in Type 2 diabetic patients.

Albuminuria↗

Evaluation of ventilatory responses in severe acidemia in diabetic ketoacidosis.

Ventilatory response in patients with severe acidemia in diabetic ketoacidosis (DKA) was unresolved. Thus, 83 patients with uncomplicated DKA were studied for the relation between arterial blood pH, calculated bicarbonate concentration (HCO3) and carbon dioxide tension (PCO2). The equation for the PCO2/HCO3 pair was: PCO2 = 1.58 x HCO3 + 7.6 (SE 2.55, r = 0.95, p < 0.01); for the PCO2/pH pair was: PCO2 = 43.8 x pH-293 (SE 6.23, r = 0.66, p < 0.01). The correlation coefficient for the PCO2/HCO3 pair was significantly greater compared to the PCO2/pH pair (p < 0.001). Multiple regression analysis showed that severe acidemia (pH < or = 7.10) per se was independently associated with PCO2 for the PCO2/HCO3 pair, but not for the PCO2/pH pair. Thus, our patients were divided into 2 groups for the PCO2/HCO3 pair: group 1 with pH < or = 7.10 (n = 25) and group 2 with pH > 7.10 (n = 58). The equations were: group 1:PCO2 = 3.18 x HCO3 + 2.88 (SE 1.72, r = 0.87, p < 0.01); group 2:PCO2 = 1.65 x HCO3 + 6.6 (SE 2.6, r = 0.95, p < 0.01). There was a significant difference between these 2 equations (p < 0.01). Mathematical simulations with 10 sets of 25 or 58 random pH/PCO2 pairs (and calculated HCO3) for "group 1' and "group 2' also showed similar results, albeit with less precision. Hence, ventilatory response in DKA varies between patients with severe acidemia and those with moderate acidemia by the PCO2/HCO3 pair, but not by the PCO2/pH pair.

Adult↗

Acute myopathy induced by colchicine in a cyclosporine-treated renal transplant recipient--a case report and review of the literature.

We report a case of colchicine-induced myopathy related to short-term, customary administration of colchicine. A 49-year-old male was admitted because of muscle weakness and myalgia that had developed 10 days previously. He had received renal transplantation 5 years previously and took cyclosporine as an immunosuppressant. Two weeks before admission, gout was developed and he took colchicine (1.2 mg b.i.d) by himself for three days. Colchicine-induced myopathy was clinically suspected, and colchicine intake was stopped immediately. After that, clinical symptoms gradually improved and serum muscle enzyme returned to normal. In this case, mild renal dysfunction and drug interaction between cyclosporine and colchicine wee suggested to be the precipitating factors of colchicine-induced myopathy.

Colchicine↗