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Biomedical subjects

K H Park

Publications and source records attributed to K H Park.

At least 19 recordsLinked to original sources
PubMed2003

Relationship between urinary profile of the endogenous steroids and postmenopausal women with stress urinary incontinence.

AIMS: The aims of this study were to investigate whether endogenous steroid hormones are (1) related to pathogenesis of stress urinary incontinence after menopause, (2) are related to severity of stress urinary incontinence, and (3) are related to prognostic parameters of stress urinary incontinence. METHODS: Twenty post-partum women with clinically diagnosed stress urinary incontinence and 20 age-matched postmenopausal women without stress urinary incontinence (control group) were evaluated. We compared urinary profile of the endogenous steroid hormones patients with stress urinary incontinence and controls, and between grade I and grade II of stress urinary incontinence. We also investigated the relationship between urinary profile of the endogenous steroid hormones and prognostic parameters of stress urinary incontinence (maximal urethral closure pressure, functional urethral length, Valsalva leak point pressure, cough leak point pressure, posterior urethrovesical angle, bladder neck descent, and stress urethral axis). The ages of the patients and those in the control group were 64.3 +/- 5.6 and 57.5 +/- 3.8 years old and the body mass indexes were 24.96 +/- 3.14 and 22.11 +/- 2.73 kg/m2 in patients and in normal subjects, respectively. Nine patients were grade I and 11 were grade II. Estrone and 17beta-estradiol only were detected in all subjects, regardless of control or patient group. It is noteworthy that there were no significant differences (P > 0.05) in the levels of estrone and 17beta-estradiol in the urine of postmenopausal normal subjects compared with in the urine of postmenopausal patients with urinary incontinence. E2/E1 ratio was not different between the two groups (P > 0.05). Among the objective steroids, DHEA, Delta4-dione, Delta5-diol, Te, DHT, 16alpha-DHT, 11-keto An, THDOC, and THB were not detected either in the urine of normal subjects and nor in the urine of the patients. After comparing androgen levels between normal subjects and patients, no significant differences (P>0.05) were detected, except for 5alpha-THB and 5alpha-THF. Neither 5alpha-THB or 5alpha-THF were detected in the patients' urine. Et/An (11beta-OH Et/11beta-OH An) concentration ratios were not significantly different between the two groups, either (P > 0.05). There were not significant differences of concentrations (micromol/g creatinine) of urinary steroids between grade I and grade II of stress urinary incontinence. Pregnanediol was significantly related to bladder neck descent in supine and sitting positions (R = 0.79, P = 0.01, and R = 0.73, P = 0.03, respectively), and pregnanetriol was significantly related to maximal urethral closure pressure and functional urethral length (R = 0.68, P = 0.04, and R = -0.79, P = 0.01, respectively). Androsterone was significantly related to bladder neck descent in supine and sitting positions (R = 0.68, P = 0.04, and R = 0.78, P = 0.01, respectively). 5-AT was significantly related to bladder neck descent in sitting position and stress urethral axis (R = 0.72, P = 0.03, and R = -0.71, P = 0.03). 11-keto Et was significantly related to bladder neck descent in supine and sitting positions and related to stress urethral axis (R = 0.82, P = 0.01, and R = 0.81, P = 0.01, R = -0.67, P = 0.04, respectively). THS was significantly related to bladder neck descent in supine and sitting positions and related to stress urethral axis (R = 0.76, P = 0.02, and R = 0.74, P = 0.02, R = -0.68, P = 0.04, respectively). THE was significantly related to bladder neck descent in sitting position (R = 0.67, P = 0.04).beta-Tetrahydrocortisol/alpha-tetrahydrocortisol (beta-THF/alpha-THF) and alpha-cortol were significantly related to maximal urethral closure pressure and functional urethral length (R = 0.74, P = 0.02, and R = -0.92, P = 0.01; R = 0.71, P = 0.36, and R = -0.87, P = 0.000, respectively). 17beta-estradiol (E2) was significantly related to bladder neck descent in supine position (R = -0.62, P = 0.04) and 17beta-estradiol/estrone (E2/E1) was significantly related to cough leak point pressure (R = 0.79, P = 0.01). In conclusion, the urinary concentrations of endogenous steroid metabolites in postmenopausal patients with stress urinary incontinence were not significantly different from normal patients and were not significantly different between grade I and grade II patients with stress urinary incontinence. Some endogenous steroid metabolites were positively or negatively significantly related to prognostic parameters of stress urinary incontinence.

Adrenal Cortex Hormones↗
PubMed2003

Misidentification of Aeromonas veronii biovar sobria as Vibrio alginolyticus by the Vitek system.

AIMS: To find the cause of misidentification of aeromonads when using the Vitek system. METHODS AND RESULTS: Two Aeromonas veronii biovar sobria isolates were misidentified as Vibrio alginolyticus by the Vitek system. Both strains' identification was confirmed by biochemical testing, API 20E/20NE kits and/or 16S RFLP analysis. Thirty-one known Aeromonas species were tested by the Vitek system using 0.45 and 0.85% saline in the suspension medium. It was not clear whether low salinity causes misidentification of Aeromonas species more frequently. CONCLUSIONS: The specified reaction time may be inappropriately short for some critical biochemical tests of some strains. An ingenious reading strategy regarding incubation time is necessary to improve identification of Aeromonas species by the Vitek system. SIGNIFICANCE AND IMPACT OF THE STUDY: To our knowledge, this is the first report of misidentification of A. veronii biovar sobria as V. alginolyticus in the Vitek system.

Aeromonas↗
PubMed2003

Comparison of localised nerve fibre layer defects in normal tension glaucoma and primary open angle glaucoma.

AIM: To compare the pattern of localised nerve fibre layer (NFL) defects in normal tension glaucoma (NTG) and primary open angle glaucoma (POAG). METHODS: 50 NTG eyes and 36 POAG eyes, all with localised NFL defects, were enrolled. On retinal NFL photography, the proximity of the defect to the centre of the fovea (angle alpha) and the sum of the angular width of the defects (angle beta) were determined. Angle alpha was the angle made by a line from the centre of the fovea to the disc centre and a line from the disc centre to the disc margin, where the nearest border of the defect met. The patterns of localised NFL defects in NTG and POAG were compared with angles alpha and beta. Independent t test was used for statistical analysis. RESULTS: Angle alpha in NTG (35.1 (SD 20.0) degrees ) was significantly smaller than that of POAG (45.9 (21.9) degrees ) (p=0.02), while angle beta in NTG (49.0 (31.9) degrees ) was significantly larger than that of POAG (33.1 (23.9) degrees ) (p=0.01). CONCLUSIONS: The pattern of NFL defects in NTG was different from that in POAG. Localised NFL defects in NTG were closer to the fovea and wider in width than those in POAG.

Adult↗
PubMed2002

Relationship between stress urinary incontinence and pelvic organ prolapse.

We investigated the objective coexisting rate of stress urinary incontinence and pelvic organ prolapse, and also compared the treatment outcomes in patients who had both conditions, treated by a corrective operation on the basis of a precise preoperative evaluation. We reviewed 97 cases who underwent urodynamic studies and evaluation of the prolapse according to the Pelvic Organ Prolapse Quantification (POP-Q) system from among patients who were admitted for treatment of either stress urinary incontinence or pelvic organ prolapse. A Burch urethropexy, either alone or with a parvaginal repair, was done to correct the stress urinary incontinence, as well as additional operations to correct prolapse of stage II or more. The patients were evaluated postoperatively for the stress urinary incontinence and the degree of prolapse at every visit. Nineteen of 30 (63.3%) patients who were admitted with stress urinary incontinence had a coexisting pelvic organ prolapse, most often of the anterior wall. In 42 of 67 (62.7%) cases admitted with pelvic organ prolapse there was a coexisting stress urinary incontinence. A total of 61 patients who had both conditions were followed for 12 months postoperatively. The recurrence rate of stress urinary incontinence and prolapse (all of which were stage II) was 3.3% and 18.0%, respectively. It was noted that the greater the preoperative stage, the higher the recurrence rate (stage II 4.35%; stage III 25.0%; stage IV 33.6%). The coexisting rates of pelvic organ prolapse in patients having stress urinary incontinence, and stress urinary incontinence in patients having a pelvic organ prolapse, were both high. Therefore, when a preoperative evaluation that simultaneously considers both conditions and the correcting surgery is based on this evaluation, the recurrence rates of both conditions could be lowered.

Aged↗
PubMed2002

The effectiveness of modified six-corner suspension in patients with paravaginal defect and stress urinary incontinence.

The purpose of our study was to evaluate the effectiveness of a modified six-corner suspension in patients with a paravaginal defect and stress urinary incontinence (SUI) by observing changes in the POP (pelvic organ prolapse) stage, substage, and the cure rates in SUI. Forty-two women patients who had a paravaginal defect and stress urinary incontinence were treated by a modified six-corner suspension at the urogynecology clinic, Yonsei University Medical Center between January 1999 and March 2000. Each patient underwent a complete physical examination and a standardized urogynecologic interview that asked about age, hormone replacement, parity, urinary symptoms and previous gynecologic surgery. From the 42 patients who had the operation, 30 patients with 1-year follow-up made up the study group. Changes from stage III ( n = 18, 60%) of the group to stage I ( n = 6, 33.3%) or stage 0 ( n = 12, 66.6%) were observed 3 months after surgery, and no further changes were observed up to 1 year after surgery, except in one case. Changes from stage IV ( n = 12) to stage 0 ( n = 3, 25%) or stage I ( n = 6, 50%) or stage II ( n = 6, 50%) were observed 3 months after surgery, but no further change was observed up to 1 year later. Changes from substage Aa (+2, +3) to -3 ( n = 27, 90%) and from substage Ba (+2,+3,+4,+5,+6,+7) to -3 ( n = 27, 90%) were observed 3 months after surgery. No further changes were observed up to 1 year. The average length of the genital hiatus was initially 4.95 cm and 2.5 cm 3 months after surgery. Little change (2.6 cm) was observed up to 1 year later. When the patients were assessed clinically by urodynamics and physical examination, none had urinary leakage symptoms up to 1 year after the operation. All patients had excellent functional results and no postoperative complaints of stress urinary incontinence. We observed that a modified six-corner suspension was surprisingly effective in patients having a paravaginal defect and a stress urinary incontinence.

Aged↗
PubMed2002

Zinc translocation accelerates infarction after mild transient focal ischemia.

Excess release of chelatable zinc (Zn(2+)) from central synaptic vesicles may contribute to the pathogenesis of selective neuronal cell death following transient forebrain ischemia, but a role in neurodegeneration after focal ischemia has not been defined. Adult male Long-Evans rats subjected to middle cerebral artery occlusion (MCAO) for 30 min followed by reperfusion developed delayed cerebral infarction reaching completion 3 days after the insult. One day after the insult, many degenerating cerebral neurons exhibited increased intracellular Zn(2+), and some labeled with the antibody against activated caspase-3. I.c.v. administration of the Zn(2+) chelator, EDTA saturated with equimolar Ca(2+) (CaEDTA), 15 min prior to ischemia attenuated subsequent Zn(2+) translocation into cortical neurons, and reduced infarct volume measured 3 days after ischemia. Although the protective effect of CaEDTA at this endpoint was substantial (about 70% infarct reduction), it was lost when insult severity was increased (from 30 to 60 min MCAO), or when infarct volume was measured at a much later time point (14 days instead of 3 days after ischemia). These data suggest that toxic Zn(2+) translocation, from presynaptic terminals to post-synaptic cell bodies, may accelerate the development of cerebral infarction following mild transient focal ischemia.

Aminoquinolines↗
PubMed2001

Modulation of the multisubstrate specificity of Thermus maltogenic amylase by truncation of the N-terminal domain and by a salt-induced shift of the monomer/dimer equilibrium.

The relation between the quaternary structure and the substrate specificity of Thermus maltogenic amylase (ThMA) has been investigated. Sedimentation diffusion equilibrium ultracentrifugation and gel filtration analyses, in combination with the crystal structure determined recently, have demonstrated that ThMA existed in a monomer/dimer equilibrium. The truncation of ThMA by removing the N-terminal domain, which is composed of 124 amino acid residues, resulted in the complete monomerization of the enzyme (ThMADelta124) accompanied by a drastic decrease in the activity for beta-cyclodextrin (beta-CD) and a relatively smaller reduction of the activity for starch. Despite the overall low activity of ThMADelta124, the activity was higher toward starch than beta-CD, and the ratio of the specific activities toward these substrates was approximately 100 fold higher than that of wild-type ThMA. Furthermore, the addition of KCl to wild-type ThMA shifted the monomer/dimer equilibrium toward the monomer. In the presence of 1.0 M KCl, the relative activity of ThMA toward beta-CD decreased to 74%, while that for soluble starch increased to 194% compared to the activities in the absence of KCl. Thus, the ThMA monomer and dimer are both inferred to be enzymatically active but with a somewhat different substrate preference. Kinetic parameters of the wild-type and truncated enzymes also are in accordance with the changes in their specific activities. We thus provide evidence in support of a model, which shows that the relative multisubstrate specificity of ThMA is influenced by the monomer/dimer equilibrium of the enzyme.

Amino Acid Sequence↗
PubMed2001

Solution conformation of alpha-conotoxin EI, a neuromuscular toxin specific for the alpha 1/delta subunit interface of torpedo nicotinic acetylcholine receptor.

A high resolution structure of alpha-conotoxin EI has been determined by (1)H NMR spectroscopy and molecular modeling. alpha-Conotoxin EI has the same disulfide framework as alpha 4/7 conotoxins targeting neuronal nicotinic acetylcholine receptors but antagonizes the neuromuscular receptor as do the alpha 3/5 and alpha A conotoxins. The unique binding preference of alpha-conotoxin EI to the alpha(1)/delta subunit interface of Torpedo neuromuscular receptor makes it a valuable structural template for superposition of various alpha-conotoxins possessing distinct receptor subtype specificities. Structural comparison of alpha-conotoxin EI with the gamma-subunit favoring alpha-conotoxin GI suggests that the Torpedo delta-subunit preference of the former originates from its second loop. Superposition of three-dimensional structures of seven alpha-conotoxins reveals that the estimated size of the toxin-binding pocket in nicotinic acetylcholine receptor is approximately 20 A (height) x 20 A (width) x 15 A (thickness).

Amino Acid Sequence↗
PubMed2001

An adenovirus expressing mutant p27 showed more potent antitumor effects than adenovirus-p27 wild type.

The main inhibitory action of p27, a cyclin-dependent kinase inhibitor (CDKI), arises from its binding with the cyclin E/cyclin-dependent kinase 2 (Cdk2) complex that results in G(1)-S arrest. Degradation of p27 is mediated by phosphorylation of Thr-187 of p27, which follows ubiquitination. In this study, we generated two adenoviruses expressing wild-type p27 (ad-p27wt) and mutant p27 (ad-p27mt), with mutation of Thr-187/Pro-188 (ACGCCC) to Met-187/Ile-188 (ATGATC), which was produced with the belief that mutant p27 would bind cyclin E/CDK2 more stably and show more potent antitumor effects. Ad-p27wt and ad-p27mt expressed p27 proteins that were indistinguishable by anti-p27 antibody. A pulse chase experiment showed that p27mt was more resistant to degradation than p27wt. In human lung cancer cell lines, ad-p27mt showed stronger growth inhibition than ad-p27wt. Both types of ad-p27 induced G(1)-S arrest and apoptosis; however, ad-p27mt induced stronger G(1)-S arrest and apoptosis. Intratumoral injection of ad-p27mt induced partial regression of established tumors and inhibited the growth of human lung cancer xenografts more strongly than ad-p27wt. From these results, we conclude that ad-p27mt has the potential to become a novel and powerful gene therapy tool.

Adenoviridae↗
PubMed2001

Calcium-dependent catalytic activity of a novel phytase from Bacillus amyloliquefaciens DS11.

The thermostable phytase from Bacillus amyloliquefaciens DS11 hydrolyzes phytate (myo-inositol hexakisphosphate, IP6) to less phosphorylated myo-inositol phosphates in the presence of Ca2+. In this report, we discuss the unique Ca2+-dependent catalytic properties of the phytase and its specific substrate requirement. Initial rate kinetic studies of the phytase indicate that the enzyme activity follows a rapid equilibrium ordered mechanism in which binding of Ca2+ to the active site is necessary for the essential activation of the enzyme. Ca2+ turned out to be also required for the substrate because the phytase is only able to hydrolyze the calcium-phytate complex. In fact, both an excess amount of free Ca2+ and an excess of free phytate, which is not complexed with each other, can act as competitive inhibitors. The Ca2+-dependent catalytic activity of the enzyme was further confirmed, and the critical amino acid residues for the binding of Ca2+ and substrate were identified by site-specific mutagenesis studies. Isothermal titration calorimetry (ITC) was used to understand if the decreased enzymatic activity was related to poor Ca2+ binding. The pH dependence of the Vmax and Vmax/Km consistently supported these observations by demonstrating that the enzyme activity is dependent on the ionization of amino acid residues that are important for the binding of Ca2+ and the substrate. The Ca2+-dependent activation of enzyme and substrate was found to be different from other histidine acid phytases that hydrolyze metal-free phytate.

6-Phytase↗
PubMed2001

Chemopreventive effect of 2-(allylthio)pyrazine (2-AP) on rat colon carcinogenesis induced by azoxymethane (AOM).

An investigation was conducted to assess the chemopreventive effects of 2-(allylthio)pyrazine (2-AP), synthesized for potential use as a chemopreventive agent, after administration during the pre-initiation and post-initiation stages in a rat colon carcinogenesis model with azoxymethane (AOM). One hundred, 5-week-old, male F344 rats were randomly divided into two experiments (n = 50 each). Experiment 1 rats were randomly divided into three groups: Group 1 rats were pre-treated with 2-AP (25 or 50 mg/kg body weight, 3 consecutive days through the route of intragastric intubations) before AOM (20 mg/kg body weight, single subcutaneous (s.c.) injection) initiation. Group 2 rats were treated with AOM alone. Group 3 rats were given 2-AP alone without AOM initiation. The animals were killed at the end of each experiment (week 5) and the aberrant crypt foci (ACF) of the colonic mucosa were assessed after staining with methylene blue. Experiment 2 rats were randomly divided into three groups: Group 1 rats were given 2-AP (10, 25 or 50 mg/kg body weight, five-times intragastric intubations per week for 5 weeks from week 3) after AOM (15 mg/kg body weight, three s.c. injections) initiation for 2 weeks. Group 2 rats were treated with AOM alone. Group 3 rats were given 2-AP alone without AOM initiation. The animals were killed at the end of the experiment (week 8) and the ACF of the colonic mucosa were quantified. Total numbers of ACF/colon in Group 1 rats (pre-treated with 2-AP) tended to decrease (2-AP, 50 mg/kg body weight) or increase (2-AP, 100 mg/kg body weight) depending on the dose level. Total numbers of ACF/colon in Group 1 rats (treated with AOM followed by 2-AP, all subgroups; 160.8 +/- 38.0; 161.8 +/- 38.1; 137.1 +/- 48.4) were decreased significantly compared with the values in Group 2 rats (AOM alone; 214.8 +/- 48.1) (P < 0.05 or 0.01). The highest dose group (2-AP, 50 mg/kg body weight) had the lowest levels of total numbers of ACF/colon among the three subgroups. Total numbers of aberrant crypts (AC)/colon of the highest dose group (340.1+/- 117.9) decreased significantly compared with the value for Group 2 rats (AOM alone; 545.1 +/- 38.3). These results thus suggest that 2-AP may have potential as a chemopreventive agent against rat colon carcinogenesis after administration of AOM during the post-initiation stage.

Animals↗
PubMed2001

Lower respiratory tract infections due to adenovirus in hospitalized Korean children: epidemiology, clinical features, and prognosis.

On occasion, outbreaks of infection with adenovirus types 3, 7, and 21 cause severe lower respiratory tract infections (LRTIs) in children. From 1990 to 1998, all cases of LRTI due to adenovirus at the Seoul National University Children's Hospital, Seoul, Korea, were reviewed. Adenoviruses were recovered from nasal aspirate specimens of 87 (5.9%) of 1472 children with LRTI. The principal adenovirus serotypes were type 2 (13 [15%] of 87 strains), type 3 (13 [15%]), and type 7 (36 [41%]). Of the 87 infections, 62 (71%) occurred in children <2 years of age, and 81 (94%) occurred in children <5 years of age. Infections due to types 3 and 7 occurred during epidemics, whereas infections due to type 2 occurred sporadically. For patients who were infected with types 3 and 7, extrapulmonary abnormalities were more common and homogeneous consolidation and pleural effusion were frequently identified on radiographs. The mortality rate was 12% overall and 19% among patients who were infected with type 7. Residual sequelae were identified in 6 (50%) of 12 patients who were infected with type 3 and in 9 (25%) of 36 who were infected with type 7. The data confirm that adenovirus types 3 and 7 can cause epidemics of severe LRTI in young children. Epidemics of LRTIs caused by adenovirus types 3 and 7 in Korea have not been described in reports published elsewhere.

Adenovirus Infections, Human↗
PubMed2001

Inhibition of beta-glycosidases by acarbose analogues containing cellobiose and lactose structures.

Acarbose analogues, containing cellobiose and lactose structures, were prepared by reaction of the two disaccharides with acarbose and Bacillus stearothermophilus maltogenic amylase. The kinetics for the inhibition by the two analogues was studied for beta-glucosidase, beta-galactosidase, cyclomaltodextrin glucanosyltransferase (CGTase), and alpha-glucosidase. Both analogues were potent competitive inhibitors for beta-glucosidase, with K(I) values in the range of 0.04-2.44 microM, and the lactose analogues were good uncompetitive inhibitors for beta-galactosidase, with K(I) values in the range of 159-415 microM, while acarbose was not an inhibitor for either enzyme at 10 and 5 mM, respectively. Both analogues were also potent mixed inhibitors for CGTase, with K(I) values in the range of 0.1-9.3 microM. The lactose analogue was a 6.4-fold better competitive inhibitor for alpha-glucosidase than was acarbose.

Acarbose↗
PubMed2001

Immunohistochemical study on the distribution of the voltage-gated potassium channels in the gerbil hippocampus.

The differential expression of specialized voltage-gated potassium (Kv) channel subtypes probably reflects the wide range of functions in the nervous system. In the present study, we investigated the distribution of six Kv1 channel subtypes in the gerbil hippocampus by immunohistochemistry. Immunoreactivities for Kv1.1, Kv1.2, Kv1.4 and Kv1.6 were observed in the pyramidal cells of the CA1-CA3 areas. In addition, many medium- to large-sized interneurons located within stratum pyramidals, stratum oriens, and stratum radiatum of CA1-CA3 were strongly immunoreactive for Kv1.4. Although there was some overlap, our results were quite different from the previous studies described in the rat and mouse hippocampus, in that we observed intense staining mainly in the cell bodies of the pyramidal cells and granule cells. As a whole, the present study has clearly shown Kv1 channel distributions in the gerbil hippocampus, which were variant between species and therefore more or less functionally significant. This study may provide useful data for the future investigations on the pathological conditions such as ischemia and epilepsy.

Animals↗
PubMed2001

Interaction of sulfonylurea-conjugated polymer with insulinoma cell line of MIN6 and its effect on insulin secretion.

A carboxylated derivative of sulfonylurea (SU), an insulinotropic agent, was synthesized and grafted onto a water-soluble polymer as a biospecific and stimulating polymer for insulin secretion. To evaluate the effect of the SU-conjugated polymer on insulin secretion, its solution in dimethyl sulfoxide was added to the culture of insulinoma cell line of MIN6 cells to make 10 nM of SU units in the medium and incubated for 3 h at 37 degrees C. The culture medium was conditioned with glucose concentration of 3.3 or 25 mM. To verify the specific interaction between the SU (K+ channel closer)-conjugated polymer and MIN6 cells, the cells were pretreated with diazoxide, an agonist of adenosine triphosphate-sensitive K+ channel (K+ channel opener), before adding the SU-conjugated polymer to the cell culture medium. This treatment suppressed the action of SUs on MIN6 cells. Fluorescence-labeled polymer with rodamine-B isothiocyanate was used to visualize the interactions, and we found that the labeled polymer strongly absorbed to MIN6 cells, probably owing to its specific interaction mediated by SU receptors on the cell membrane. The fluorescence intensity on the cells significantly increased with an increase in incubation time and polymer concentration. A confocal laser microscopic study further confirmed this interaction. The results from this study provided evidence that SU-conjugated copolymer stimulates insulin secretion by specific interactions of SU moieties in the polymer with MIN6 cells.

Acrylic Resins↗
PubMed2001

Analysis of fatty acids by graphite plate laser desorption/ionization time-of-flight mass spectrometry.

Fatty acids obtained from triglycerides (trioelin, tripalmitin), foods (milk, corn oil), and phospholipids (phosphotidylcholine, phosphotidylserine, phosphatidic acid) upon alkaline hydrolysis were observed directly without derivatization by graphite plate laser desorption/ionization time-of-flight mass spectrometry (GPLDI-TOFMS). Mass-to-charge ratios predicted for sodium adducts of expected fatty acids (e.g. palmitic, oleic, linoleic and arachidonic acids) were observed without interference. Although at present no quantitation is possible, the graphite plate method enables a simple and rapid qualitative analysis of fatty acids.

Animals↗
PubMed2001

Polycystic ovarian syndrome (PCOS) and insulin resistance.

OBJECTIVES: Polycystic ovary syndrome (PCOS) presents a high risk of developing type 2 diabetes mellitus. We studied a group of women with PCOS and evaluated this defect in insulin action. METHODS: The study population consisted of nine PCOS women, six obese type 2 diabetic patients, and five controls whose body mass index (BMI) was similar to that of the nine PCOS women. The 75-g oral glucose tolerance test (OGTT) and the hyperinsulinemic euglycemic glucose clamp test were performed. Clinical characteristics and the metabolic profiles, including the insulin sensitivity index (ISI), were compared. RESULTS: PCOS women showed significantly elevated insulin responses during OGTT, but their blood glucose levels were comparable with the controls. The subjects with PCOS had more insulin resistance than the other groups. There was no difference among the groups in terms of clinical characteristics and metabolic profiles, except age, luteinzing hormone (LH), testosterone, and sex hormone binding globulin (SHBG). CONCLUSION: We conclude that PCOS women have significant insulin resistance which is independent of adiposity.

Adult↗