Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “HS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 613 records · Page 34Linked to original sources
PubMed1995

Color flow Doppler determination of transmitral flow and orifice area in mitral stenosis: experimental evaluation of the proximal flow-convergence method.

To evaluate the in vivo accuracy of color Doppler flow-convergence methods for determining transmitral flow volumes and effective orifice areas in mitral stenosis, we studied two models for flow-convergence surface geometry, a hemispheric (HS) model and an oblate hemispheroid (OH) model in a chronic animal model with quantifiable mitral flows. Color Doppler flow mapping of the proximal flow-convergence region has been reported to be useful for evaluation of intracardiac flows. Flow-convergence methods in patients with mitral stenosis that use HS assumption for the isovelocity surface have resulted in underestimation of actual flows. Chronic mitral stenosis was created surgically in six sheep with annuloplasty rings (group 1) and 11 sheep with bioprosthetic porcine valves (group 2). Hemodynamic and echocardiographic/Doppler studies (n = 18 in group 1; n = 21 in group 2) were performed 20 to 34 weeks later. Left ventricular inflow obstruction was of varied severity, with mean transmitral valve gradients in group 1 ranging from 1.3 to 18 mm Hg and in group 2 ranging from 6.3 to 25.6 mm Hg. Although transmitral flows derived by both geometric flow convergence models showed significant correlations with reference cardiac outputs, the correlations for the OH model were better than those for the HS model (group 1, r = 0.86 for the OH model vs r = 0.72 for the HS model; group 2; r = 0.84 for the OH model vs r = 0.62 for the HS model). The OH model was also superior to the HS model in determining effective orifice areas compared to reference orifice areas determined by postmortem planimetry of anatomic orifices (group 1 only, r = 0.64 for OH vs 0.58 for HS), by the Gorlin and Gorlin formula (group 1, r = 0.63 for OH vs 0.72 for HS; group 2, r = 0.82 for OH vs 0.76 for HS), and by the Doppler pressure half-time method (group 1, r = 0.76 for OH vs 0.69 for HS; group 2, r = 0.84 for OH vs 0.62 for HS).(ABSTRACT TRUNCATED AT 400 WORDS)

Analysis of Variance↗
PubMed1994

A new ELISA for the detection of anti-heparan sulfate reactivity, using photobiotinylated antigen.

Autoantibodies reacting with a great variety of autoantigens are characteristic for the autoimmune disease systemic lupus erythematosus (SLE). Although reactivity with heparan sulfate (HS) in sera of patients with SLE is found in association with the occurrence of nephritis, the aetiological significance of this association is not clear. The assay which is generally used to measure anti-HS reactivity is subject to false-positive results, as a consequence of the binding of negatively charged moieties within immune complexes to the precoat employed (protamine sulfate). Therefore, we have developed a new ELISA in which photobiotinylated HS is efficiently and reproducibly bound to streptavidin-coated wells. We compared the new ELISA with the classical anti-HS ELISA by testing culture supernatants of 20 murine monoclonal antibodies (mAb) to DNA (containing free anti-DNA and anti-DNA/nucleosome immune complexes) and preparations of these mAb (containing only free anti-DNA), purified under dissociating conditions. In the classical anti-HS ELISA, 14 out of 20 of the culture supernatants reacted positively with HS; after purification no reactivity remained. The discrepancy must be due to anti-DNA/nucleosome immune complexes present in the culture supernatants. In the new ELISA only four out of 20 culture supernatants and one of the purified preparations reacted with HS. This latter reactivity is probably not specific, since this mAb also reacted with streptavidin alone. To find out whether there is a correlation between the occurrence of nephritis and anti-HS reactivity, measured in this new anti-HS ELISA, we tested sera of patients with a renal- or non-renal exacerbation of SLE in the newly developed anti-HS ELISA. We observed a correlation between anti-HS reactivity and nephritis.

Animals↗
PubMed1984

Evidence for diabetes-induced alterations in the sulfation of heparin sulfate intestinal epithelial cells.

35S-heparan sulfate (HS) metabolism by intestinal epithelial cells isolated from streptozotocin-diabetic and control rats was studied. In diabetic cells, a greater amount of 35S-radioactivity was incorporated into HS, however specific radioactivity of this polysaccharide was decreased. Studies into the distribution of sulfate residues in HS after selective deamination of the glucosamine units within the glycosaminoglycan (GAG)-chain, demonstrated that O-sulfate groups are preferentially located in relatively small deamination products: tetrasaccharides and disaccharides. A lower amount of radioactivity related to N-sulfate groups was found in HS from diabetic cells compared to that of control cells demonstrating that, in diabetes, less glucosamine residues within HS chains are subjected to N-sulfation. An increase in the percentage of 35-sulfate and in the percentage amount of uronic acid in tetrasaccharides of HS of diabetic cells indicated that a greater number of tetrasaccharides were generated by deaminative degradation of this HS. Since a decrease in the specific activity of uronic acid in disaccharides as in tetrasaccharides from HS of diabetic cells was observed, it is clear that the degree of O-sulfation of this HS is reduced. It is suggested, that "in vivo" changes in HS metabolism in diabetic intestinal epithelial cells lie in a disturbance in the degree of N- and O-sulfation of disaccharide units within the HS macromolecule.

Animals↗
PubMed2005

Characterization of the structure of antithrombin-binding heparan sulfate generated by heparan sulfate 3-O-sulfotransferase 5.

The 3-O-sulfation of glucosamine is a key modification step during the biosynthesis of anticoagulant heparan sulfate (HS). Both heparan sulfate 3-O-sulfotransferase -1 (3-OST-1) and 3-O-sulfotransferase-5 (3-OST-5) transfer sulfate to the 3-OH group of glucosamine to generate antithrombin-binding heparan sulfate (HS(act)). Here, we reported the isolation and characterization of the antithrombin-binding HS oligosaccharides generated by 3-OST-5 (3-OST-5 oligo(act)). (3)H-labeled HS of Chinese hamster ovary cells was exhaustively modified by 3-OST-1 to remove the 3-OST-1 modification sites followed by antithrombin-affinity fractionation. The non-antithrombin-binding fraction of 3-OST-1 pretreated HS was further modified by 3-OST-5 to generate additional antithrombin-binding HS, which was designated as 3-OST-5 HS(act). Structural analysis of 3-OST-5 HS(act) revealed that the antithrombin-binding site of 3-OST-5 HS(act) is located within a domain clustered with N-sulfated glucosamine units. We also isolated 3-OST-5 antithrombin-binding oligosaccharides (3-OST-5 oligo(act)) from high pH nitrous acid degraded 3-OST-5 HS(act). A disaccharide analysis revealed that 3-OST-5 oligo(act) were composed of multiple 3-O-sulfated glucosamine units. Our results provide additional insights on the relationship between the anticoagulant activity and structure of HS.

Animals↗
PubMed2005

Fos expression variances in mouse hypothalamus upon physical and osmotic stimuli: co-staining with vasopressin, oxytocin, and tyrosine hydroxylase.

Fos expression in the hypothalamus and its quantification in vasopressinergic (AVP), oxytocinergic (OXY) and tyrosine hydroxylase (TH) immunoreactive cells in the hypothalamic paraventricular (PVN), supraoptic (SON), suprachiasmatic (SCh), and arcuate (Arc) nuclei was performed in response to physiologically two different, i.e. osmotic (i.p. hypertonic saline, HS) and immobilization (IMO), stimuli in mouse using a dual Fos-neuropeptide immunohistochemistry. Both 60 min of HS and 120 min of IMO evoked Fos induction in many hypothalamic structures, whereas, HS evoked more extensive Fos labeling than IMO in the SON, ventromedial (VMN) and dorsomedial (NDM) hypothalamic nuclei and the retrochiasmatic area (RCh). Other hypothalamic structures including the anterior hypothalamic area (AHA), the latero-anterior hypothalamic nucleus (LA), the Arc, the perifornical nucleus (PeF), and the lateral hypothalamic area (LH) showed similar Fos incidence after both HS and IMO. However, after both stimuli explicitly most extensive Fos expression was observed in the PVN. In addition, in the PVN substantially more Fos-AVP (62-67% versus 10-15%) and Fos-OXY (38-45% versus 4-8%) perikarya were observed after HS than IMO, respectively. Incidence of TH-immunoreactive Fos labeled cells in the PVN was also more frequent after HS. In the SON, HS activated more than 50% of AVP and OXY neurons while IMO less than 4%. The number of TH activated neurons in Arc was also higher after HS (11%) than IMO (4%). Lowest number of colocalizations was revealed in the SCh where both HS and IMO activated around 2% of AVP neurons. The present data demonstrate that both HS and IMO are powerful stimuli for the majority of hypothalamic structures displaying considerable topographic similarity in Fos expression suggesting their multifunctional involvement. The quantity and phenotypic differences of activated hypothalamic neurons may speak out for functional dissimilarities in response to HS and IMO.

Animals↗
PubMed2005

High incidence, early onset of histiocytic sarcomas in mice with Hertwig's anemia.

OBJECTIVE: Histiocytic sarcoma (HS) is a rare, rapidly disseminated, usually lethal tumor in humans. Treatment specific for HS has not been developed primarily due to deficiencies of appropriate animal models with high incidence/early onset. Mice with Hertwig's anemia (an/an) provide a potential model. METHODS: Here, we compare HS susceptibility in an/an and unaffected control mice maintained on three genetic backgrounds. As a potential therapeutic measure, genetically marked bone marrow is transplanted between high and low susceptibility animals. RESULTS: HS is detected earlier and the overall incidence is 15-fold higher in WBB6F1(F1)-an/an than in F1-+/?, B6-an/an and -+/? mice. Neither WB-an/an nor their normal WB-+/? littermates present with HS. Liver myelopoiesis and aneuploidy coexist with HS but the former is also rampant (33.7% incidence) in HS-free +/? and an/an mice. Marrow transplantation experiments provide evidence that (1) myelopoiesis is associated with HS and (2) early-onset/high-incidence HS is blocked by using late-onset F1-+/+ mice, as either donor or recipient. CONCLUSIONS: Homozygosity for an on an F1 genetic background is essential for high-incidence/early-onset HS; myelopoiesis and HS coexist; and therapeutic transplantation may be feasible.

Animals↗
PubMed2006

Headspace gas chromatographic determination of ethanol: the use of factorial design to study effects of blood storage and headspace conditions on ethanol stability and acetaldehyde formation in whole blood and plasma.

Our headspace gas chromatographic flame ionization detection (HS-GC-FID) method for ethanol determination showed slightly, but consistently, low ethanol concentrations in whole blood (blood) in proficiency testing programs (QC-samples). Ethanol and acetaldehyde were determined using HS-GC-FID with capillary columns, headspace equilibration temperature (HS-T degrees ) of 70 degrees C and 20 min equilibration time (HS-EqT). Full factorial designs were used to study the variables HS-T degrees (50 degrees -70 degrees C), HS-EqT (15-25 min), ethanol concentration (0.20-1.20 g/kg) and storage at room temperature (0-6 days) with three sample-sets; plasma, hemolyzed blood and non-hemolyzed blood. A decrease in the ethanol concentration in blood was seen as a nearly equivalent increase in the acetaldehyde concentration. This effect was not observed in plasma, indicating chemical oxidation of ethanol to acetaldehyde in the presence of red blood cells. The variables showed different magnitude of effects in hemolyzed and non-hemolyzed blood. A decrease in ethanol concentration was seen even after a few days of storage and also when changing the HS-T degrees from 50 to 70 degrees C. The formation of acetaldehyde was dependent on all the variables and combinations of these (interactions) and HS-T degrees was involved in all the significant interaction effects. Favorable instrumental conditions were found to be HS-T degrees of 50 degrees C and HS-EqT of 15-25 min. The ethanol concentrations obtained for the range 0.04-2.5 g/kg after analyzing authentic forensic blood samples with a HS-T degrees of 50 degrees C were statistically significantly higher than at 70 degrees C (+0.0154 g/kg, p < 0.0001, n = 180). In conclusion, chemical oxidation of ethanol to acetaldehyde in the presence of red blood cells has been shown to contribute to lowered ethanol concentrations in blood samples. Storage conditions before analysis and the headspace equilibration temperature during analysis were important for the determination of blood ethanol concentrations.

Acetaldehyde↗
PubMedDate not supplied

Timing of hyperthermic preconditioning affects islet resistance against inflammation.

BACKGROUND: Heat exposure of isolated islets enhances resistance against inflammation but decreases islet graft function. In contrast, donor preconditioning by whole-body hyperthermia increases islet ischemic tolerance and improves viability of pancreatic isografts. This study aimed to compare yield, viability, and inflammatory resistance of rat islets subjected to heat shock prior to (pre-HS) or after isolation (post-HS). METHODS: Islets were isolated as previously described. HS (42 degrees C/45 min) was induced 12 hours before islet isolation (pre-HS, n = 31) or in freshly isolated islets prior to 12 hours of recovery at 37 degrees C (post-HS, n = 12). Islets continuously incubated at 37 degrees C served as controls (n = 33). Proinflammatory treatment included incubation with 0.05 mmol/L H(2)O(2), 1.0 mmol/L DETA-NO or cytokines (interleukin-1beta + tumor necrosis factoralpha + interferongamma). RESULTS: Purified islet yield was 1200 +/- 80 IEQ in unconditioned donors (n = 45) and 980 +/- 80 IEQ after pre-HS (ns). Islet viability was not affected by post-HS, but the glucose stimulation index (P < 0.001, P < 0.01) and formazan production (P < 0.05) were significantly lower compared to pre-HS or sham treatment. The expression of heat shock protein HSP70 in pre-HS islets was slightly higher compared to controls (ns) but lower compared to post-HS islets (P < 0.05), correlating with the resistance against H(2)O(2) and DETA-NO compared to post-HS islets (P < 0.05) or controls (ns). Cytokines did not affect mitochondrial formazan production. CONCLUSIONS: The findings indicate that hyperthermic islet treatment is less harmful if performed in the native pancreatic environment. This beneficial effect is associated with a decreased HSP70 expression resulting in a reduced resistance against inflammatory mechanisms.

Animals↗
PubMed1997

Characterization of Campylobacter jejuni isolates from patients with Guillain-Barré syndrome.

Campylobacter jejuni is a major pathogen preceding Guillain-Barré syndrome (GBS), and most C. jejuni isolates from GBS patients belong to Penner serotype 19 (heat-stable; HS-19). We analyzed sixteen independent clinical isolates from GBS patients, twelve of which belonged to HS-19, three to HS-2, and one to HS-4, using PCR-based RFLP analysis of a flagellin-A (flaA) gene. Two isolates from patients with Miller Fisher syndrome (MFS), and 27 from patients with uncomplicated enteritis were also examined. All HS-19 isolates, regardless of GBS, showed an identical pattern (Cj-1) by RFLP typing and were distinguishable from those of the other Penner serogroups. In contrast, HS-2 and HS-4 isolates were divided into several different RFLP groups, suggesting HS-19 strains are genetically distinctive among C. jejuni isolates. A DNA fingerprinting method also failed to detect any specific band pattern for GBS-related C. jejuni isolates. We examined relationships among anti-GM1 antibody titres in the sera of GBS patients, clinical forms of GBS, serotype of C. jejuni, and the presence of GM1-like structures in lipopolysaccharide (LPS) components from C. jejuni isolates by immunoblotting. HS-19 related GBS was significantly associated with elevated anti-GM1 antibody titers in the sera of the patients, but not associated with any clinical pattern of GBS. No significant correlations were found between anti-GM1 antibody and the pattern of disease, or between GBS-related C. jejuni strains and the presence of GM1-like structures. HS-19 strains seem to be unique among C. jejuni isolates, and HS-19-related GBS may provide an excellent model for clarification of the pathogenesis of GBS.

Blotting, Western↗
PubMed2000

The influence of humic substances on the speciation and bioavailability of dissolved mercury and methylmercury, measured as uptake by Chaoborus larvae and loss by volatilization.

The influence of dissolved humic substances (HS) on the bioavailability of dissolved inorganic and methyl mercury (Hg) was quantified by measuring the direct uptake of 203Hg in Chaoborus larvae using laboratory microcosms containing artificial freshwater. The animals were exposed individually in triplicate aquaria at 10 different concentrations of HS covering the whole range found in natural freshwaters (0-110 mg C l(-1)). Mercury-203 concentrations were monitored repeatedly in the same individuals and in their ambient water during up to 10 days. Near-steady state Hg concentrations in Chaoborus were usually reached within 5 days. The bioconcentration factor (BCF, direct uptake only) for the larvae in the absence of HS was 0.55+/-0.09 (S.E.) ml individual(-1) for inorganic Hg and 5.3+/-0.7 ml individual(-1) for methyl Hg, thus showing a 10-fold difference. Normalizing to the organic carbon content of the larvae yields a BCF(OC) in the absence of HS of 2.8+/-0.4 x 10(3) ml (gC)(-1) for inorganic Hg and 2.7+/-0.3 x 10(4) ml (gC)(-1) for methyl Hg. The uptake of both inorganic and methyl Hg decreased markedly with increasing concentration of HS. For inorganic Hg, the decrease in uptake was most pronounced at HS concentrations below 0.2 mg C l(-1). For methyl Hg, the relationship between uptake and log([HS]) was sigmoid, showing a reduction by > 90% when increasing HS concentrations from 1 to 50 mg C l(-1). Similar patterns were observed for losses of Hg from the water phase, mainly through volatilization. These results have implications for both the biouptake and the abiotic cycling of Hg in natural ecosystems and suggest that most dissolved inorganic Hg is bound to dissolved organic matter in most natural freshwaters, whereas dissolved methyl Hg is bound only in humic waters. Assuming that only free aqueous Hg is taken up by the organisms, the rather simple methodology employed here can be used for estimating distribution coefficients (K(OC)) for Hg between HS and water. In this study, the K(OC) values were 2.5+/-0.7 (S.E.) x 10(7) ml (gC)(-1) for inorganic Hg and 1.5+/-0.6 x 10(5) ml (gC)(-1) for methyl Hg. Values of similar magnitude were derived from observed losses of Hg from the water phase, supporting the assumption of an immobilization of both inorganic and methyl Hg by HS. The strong negative influence of dissolved HS on the bioavailability of both inorganic and methyl Hg in freshwater suggests that the high Hg levels often found in fish from humic lakes in the boreal forest zone cannot be explained alone by direct uptake of methyl Hg from the water phase into biota at low trophic levels.

Animals↗
PubMed2001

Efficacy and tolerability of fluvastatin extended-release delivery system: a pooled analysis.

BACKGROUND: At high doses, the pharmacokinetics of fluvastatin immediate-release (IR) are nonlinear, possibly due to saturation of hepatic uptake. Fluvastatin delivery to the liver in a slower but sustained fashion would be expected to avoid hepatic saturation without elevating systemic drug levels. OBJECTIVE: This pooled analysis compared the efficacy and tolerability of extended-release (XL) 80-mg and IR 40-mg formulations of fluvastatin in lowering low-density lipoprotein cholesterol (LDL-C) and triglyceride (TG) levels and raising high-density lipoprotein cholesterol (HDL-C) levels in patients with hypercholesterolemia. METHODS: Data were pooled from 3 double-blind, randomized, active-controlled, multicenter, parallel-group studies that compared changes in lipid and apolipoprotein levels with fluvastatin XL 80 mg at bedtime (HS) with changes in fluvastatin IR 40 mg HS or BID in patients aged > or =18 years with primary hypercholesterolemia (consistently elevated LDL-C level [> or =160 mg/dL] and plasma TG levels < or =400 mg/dL). The primary efficacy variable was percent change in LDL-C from baseline. RESULTS: The pooled analysis provided an intent-to-treat efficacy study population of 1674 patients. At 4 weeks, fluvastatin XL 80 mg HS reduced LDL-C levels by a mean of 36.3% (median 38%), significantly greater than a mean reduction of 25.9% (median 27%) seen with fluvastatin IR 40 mg HS, and an incremental additional mean reduction in LDL-C of 10.4% (P < 0.001). At 4 and 24 weeks, fluvastatin XL 80 mg HS provided an LDL-C reduction equivalent to fluvastatin IR 40 mg BID (P < 0.001 for noninferiority). Significant, dose-related changes in HDL-C, LDL-C:HDL-C ratio, total cholesterol, TG, and apolipoprotein A-I and apolipoprotein B levels also occurred. Mean HDL-C level increased by 8.7% and median TG level decreased by 19% with fluvastatin XL 80 mg HS (P < 0.001 and P < 0.05 vs fluvastatin IR 40 mg HS, respectively). Maximum mean increases in HDL-C level (21%) and median decreases in TG level (31%) with fluvastatin XL 80 mg HS occurred in patients with type IIb dyslipidemia and the highest baseline TG. Adverse events were mild, with similar frequency in all treatment groups. CONCLUSIONS: Once-daily administration of fluvastatin XL 80 mg provides enhanced efficacy with an additional 10.4% reduction in LDL-C levels compared with fluvastatin IR 40 mg HS, and superior increases in HDL-C levels, particularly in patients with elevated TG levels (P < 0.05 vs fluvastatin IR 40 mg HS). Fluvastatin XL 80 mg HS has a good tolerability profile and is effective as starting and maintenance lipid-lowering treatment in patients with type II hypercholesterolemia.

Adult↗
PubMed1998

[Claude Bernard-Horner syndrome and its opposite, Pourfour du Petit syndrome, in anesthesia and intensive care].

OBJECTIVE: To analyse cases of Horner's syndrome (HS) and its opposite, Pourfour du Petit's syndrome (PPS), occurring in anaesthesia and intensive therapy with consideration of the data of current literature. DATA SOURCES: For this paper we have reviewed the French, English and German literature published in anaesthesia and intensive care journals using Medline search and the current textbooks. STUDY SELECTION: All observational studies on these syndromes, whether clinical cases or letters to the editor, form the basis for this article. DATA EXTRACTION: The articles were analysed mainly with regard to diagnosis, therapy and prognosis of syndromes due to iatrogenic causes. DATA SYNTHESIS: HS is caused by a paralysis of the ipsilateral sympathetic cervical chain and includes a ptosis of the upper eyelid, a slight elevation of the lower lid, a sinking of the eyeball, a constriction of the pupil, a narowing of the palpebral fissure, a nasal stuffiness associated with anhidrosis, and flushing of the affected side of the face. Regional anaesthesia (intra-oral anaesthesia, brachial plexus block, epidural anaesthesia whether by thoracic, lumbar or caudal approach, as well as interpleural analgesia) is the main anaesthetic cause for HS. HS due to the effect of a local anaesthetic is transient, it can precede a high spinal block and a cardiovascular collapse. HS from puncture of the internal jugular vein is most often permanent. When transient, HS regresses within 3 months after puncture. Other causes of HS include intraoperative posture, pleural drain, neck surgery, neck trauma. A mydriatic collyrium, such as phenylephrine, resolves ptosis for less than 1 hour and results in blurred vision from pupillary dilation. Major ptosis requires surgery. PPS is the reciprocal HS and is caused by a stimulation of the ipsilateral sympathetic cervical chain. PPS can precede HS. It carries a risk for conjunctivitis, keratitis and epiphora in case of major exophthalmia. PPS is often reported as an unilateral mydriasis. PPS has the same causes as HS. Myotic collyriums are relatively inefficient. Major lid retraction requires a tarsorraphy, pomades and nocturnal lid occlusion. A part of HS and most PPS occurring in anaesthesia and intensive care remain unrecognized or are recognized with delay, especially if they remain minor and transient or when they occur in unconscious patients, in horizontal posture.

Adolescent↗
PubMed1999

Prediction of presence of hippocampal sclerosis from intracarotid amobarbital procedure memory asymmetry scores and epilepsy on set age.

Identification of the pathological status of the hippocampus prior to surgery is important since the absence of hippocampal sclerosis (HS) carries risks to memory function following anterior temporal lobectomy (ATL). We studied 62 patients undergoing ATL (31 L, 31 R) for intractable epilepsy of temporal lobe origin in whom no pathology was identified apart from HS. An intracarotid amobarbital procedure (IAP) was performed as part of the preoperative evaluation. All patients were left hemisphere dominant for language. IAP memory testing was according to the protocol of Loring. We examined IAP memory asymmetry scores at four levels of difference (<2, > or =2, > or =4, > or =6) as a function of the presence (HS+) or absence (HS-) of HS. A logistic regression analysis was performed with HS+ as the dependent variable, and age at onset of epilepsy, age at time of surgery, gender, side of surgery and significant IAP memory asymmetry as independent variables. At each level of memory asymmetry, onset age and memory asymmetry were the only predictors of HS+. Younger age at onset was associated with HS+. Curves were constructed showing probability of HS+ for age at onset for each level of asymmetry. These can be used to predict the likelihood of presence of HS based on age at onset of epilepsy and the IAP memory asymmetry score. It is concluded that IAP memory asymmetry scores reflect the functional and pathological status of the hippocampus, and greater asymmetry increases the probability of finding HS in the resected hippocampus.

Adult↗
PubMed1998

Potassium and sodium intake and excretion in calcium stone forming patients.

OBJECTIVE: To determine mean potassium (K) intake and its correlation with urinary calcium (uCa) and citrate excretion, as well as uCa, sodium (Na), and K levels of calcium stone forming patients. We determined the K-rich foods most commonly consumed by these patients. DESIGN: Case-control. SETTING: University-affiliated outpatient renal Lithiasis Unit. PATIENTS AND CONTROLS: One hundred hypercalciuric calcium stone forming patients (CSF, 54 men/46 women), 37 with associated hypocitraturia, were sequentially enrolled in the study that was performed before the initiation of any care for their renal stones. The control group consisted of 100 age-matched healthy subjects (HS, 47 men/53 women) who were laboratory employees with no history of renal stones. INTERVENTION: The analyses consisted of a 3-day dietary record to determine the mean K and calcium (Ca) intakes, and a 24-hour urine sample with measurements of K, Ca, Na, and citrate. MAIN OUTCOME MEASURE: K and Na intake determined by dietary record. RESULTS: uCa and Na levels and the Na/K ratio were significantly higher for CSF versus HS (238 +/- 118 v 148 +/- 74 mg/24 hours, 238 +/- 100 v 181 +/- 68 mEq/24 hours, 6.6 +/- 3.5 v 5.1 +/- 2.3, respectively, P < .05). The mean citrate excretion was lower in CSF than in HS patients (410 +/- 265 v 530 +/- 240 mg/24 hours). Mean uCa did not differ between groups. CSF patients showed a higher sodium chloride intake compared with HS (14 +/- 4 vs 8 +/- 3 g/day). The mean Ca intake of CSF and HS were 559 +/- 327 and 457 +/- 363 mg/day, respectively. The mean K intake of CSF and HS were 58 +/- 17 and 51 +/- 27 mEq/day. A positive correlation was observed between uCa and urinary sodium (r = .40 and r = .65, P < .05), urinary potassium and urinary citrate (r = .25 and r = .53, P < .05), uCa and Na/K (r = .33 and r = .56, P < .05) respectively for CSF and HS. The following were the K-rich foods consumed at least once a day by these groups: beans (by 70% of CSF and 75% of HS), tomatoes (by 42% of CSF and 50% of HS), oranges (by 30% of CSF and 55% of HS), and bananas (by 42% of CSF and 23% of HS). CONCLUSION: Despite the consumption of K-rich foods at least once a day, the mean K intake by CSF patients was 58 mEq/day. This intake can still be considered to be low, although it meets recommended daily dietary allowance requirements. Therefore, we describe herein a population of CSF with high-Na intake and normal- to low-K intake, which may contribute to stone formation.

Adult↗
PubMed2006

Dual effects of heat stress on tumor necrosis factor-alpha-induced hepatocyte apoptosis in mice.

The major heat shock protein, HSP70, plays a critical role in cell survival in response to stress, possibly by inhibiting a number of antisurvival pathways. However, heat stress (HS) and HSPs also sensitize cells to certain apoptotic stimuli, such as TNF-alpha. To clarify the relations between HS and apoptosis, we examined the differential effects of the intensity of HS on liver injury and apoptosis induced by TNF-alpha in mice. TNF-alpha was injected into D-galactosamine (GalN)-sensitized mice that were pretreated with or without HS. Liver injury was assessed biochemically and histologically. In GalN-sensitized mice, application of HS for 7 days led to significant enhancement of TNF-alpha-induced hepatotoxicity, despite upregulation of HSP70 in the liver. In contrast, application of HS for 1 day led to attenuation of TNF-alpha-induced liver injury. Repeated HS decreased the levels of the FLICE inhibitory protein short (FLIP(S)) and activated caspase-8 in the liver. The caspase-8 inhibitor Z-IETD-FMK effectively protected both the nontreated and HS-pretreated mice from the hepatotoxicity induced by GalN/TNF-alpha. HS shows dual effects on TNF-alpha-induced hepatocyte apoptosis. Exposure to repeated HS, but not to single HS, leads to enhancement of TNF-alpha-induced hepatocyte apoptosis via the interaction of FLIP and caspase-8.

Animals↗
PubMed1995

Brefeldin A inhibits the endocytosis of plasma-membrane-associated heparan sulphate proteoglycans of cultured rat ovarian granulosa cells.

Rat ovarian granulosa cells were labelled with [35S]sulphate for 0.5-20 h and chased in the presence or absence of 1-2 micrograms/ml of brefeldin A (BFA) for up to 21 h. Heparan [35S]sulphate (HS) proteoglycans from the culture medium, plasma membrane and intracellular fractions were then analysed by gel chromatography. In the absence of BFA, about 85% of the plasma membrane-associated HS proteoglycans were endocytosed and subsequently degraded intracellularly. Recirculation of the HS proteoglycans between the intracellular pool and the cell surface was not observed. Exposing the cells to BFA for less than 1 h did not influence the turnover of the HS proteoglycans, whereas the effect of the drug on the Golgi functions reached a maximum in approx. 10 min. When the cells were treated with BFA for more than 1-2 h, the rate of endocytosis of HS proteoglycans was reduced to about 50% of the control. The delivery of endocytosed HS proteoglycans to lysosomes were not affected by the drug. Cycloheximide also reduced the endocytosis of HS proteoglycans, but not as much as BFA, indicating that the inhibitory effect of BFA can be only partly accounted for by a block of protein transport from the endoplasmic reticulum to the plasma membrane. In contrast with the endocytosis of HS proteoglycans, neither that of 125I-transferrin, known to be mediated by clathrin-coated vesicles, nor that of 125I-ricin, a marker molecule for bulk endocytosis, was affected by BFA. The half-life of 125I-transferrin and 125I-ricin in the plasma membrane was about 10 and 25 min respectively compared with about 5 h for the HS proteoglycans. Altogether, these results indicate that the endocytosis of plasma-membrane-associated HS proteoglycans is mediated by different mechanisms than the endocytosis of most other cell-surface proteins. Further, the mechanisms involved in the endocytosis of HS proteoglycans are sensitive to BFA.

Animals↗
PubMed1990

Heparan sulphate proteoglycans on rat parathyroid cells recycle in low Ca2+ medium.

A rat parathyroid cell line, with some differentiated properties of the parathyroid gland, synthesizes predominantly a heparan sulphate proteoglycan (HS-PG) typical of cell surface HS-PGs (core protein = approximately 70 kDa, three to four HS chains of approximately 30 kDa). A 10 min pulse-chase protocol was used to determine the metabolic fate of the HS-PGs for cells maintained in 2.1 mM-Ca2+ (high Ca) or in 0.05 mM-Ca2+ (low Ca). In low Ca, approximately 60% of the labelled HS-PGs reach the cell surface (t1/2 = approximately 15 min) as determined by trypsin accessibility. This population of HS-PGs recycles (t1/2 = approximately 9 min) between the cell surface and an intracellular (presumably endosome) compartment. After approximately 2 h, this population of HS-PGs is internalized and rapidly degraded in lysosomes. In high Ca, only approximately 10% of the HS-PGs reach the cell surface, where they do not recycle. Changing from high to low Ca any time between 30-120 min of chase, rapidly (t1/2 less than 4 min) redistributes the HS-PGs to the cell surface where they begin recycling; conversely, changing from low to high Ca leads to a rapid sequestration of the cell surface HS-PGs within the cells. Other divalent cations fail to mimic the response to Ca2+. The results suggest that most of the HS-PGs in this cell line are anchored in a membrane compartment involved in a transport process between endosomes and the cell surface which is regulated by the concentration of extracellular Ca2+.

Animals↗
PubMed2003

Neocortical temporal FDG-PET hypometabolism correlates with temporal lobe atrophy in hippocampal sclerosis associated with microscopic cortical dysplasia.

PURPOSE: Medically intractable temporal lobe epilepsy (TLE) due to hippocampal sclerosis (HS), with or without cortical dysplasia (CD), is associated with atrophy of the hippocampal formation and regional fluorodeoxyglucose positron-emission tomography (FDG-PET) hypometabolism. The relation between areas of functional and structural abnormalities is not well understood. We investigate the relation between FDG-PET metabolism and temporal lobe (TL) and hippocampal atrophy in patients with histologically proven isolated HS and HS associated with CD. METHODS: Twenty-three patients underwent en bloc resection of the mesial and anterolateral neocortical structures. Ten patients were diagnosed with isolated HS; 13 patients had associated microscopic CD. Temporal lobe volumes (TLVs) and hippocampal volumes were measured. Magnetic resonance imaging (MRI) and PET were co-registered, and regions of interest (ROIs) determined as gray matter of the mesial, lateral, and anterior temporal lobe. RESULTS: All patients (HS with or without CD) had significant ipsilateral PET hypometabolism in all three regions studied (p < 0.0001). In patients with isolated HS, the most prominent hypometabolism was in the anterior and mesial temporal lobe, whereas in dual pathology, it was in the lateral temporal lobe. TLVs and hippocampal volumes were significantly smaller on the epileptogenic side (p < 0.05). The PET asymmetries ipsilateral/contralateral to the epileptogenic zone and TLV asymmetries correlated significantly for the anterior and lateral temporal lobes (p < 0.05) in the HS+CD group, but not in the isolated HS group. Mesial temporal hypometabolism was not significantly different between the two groups. CONCLUSIONS: Temporal neocortical microscopic CD with concurrent HS is associated with more prominent lateral temporal metabolic dysfunction compared with isolated HS in TL atrophy. Further studies are needed to confirm these findings and correlate the PET hypometabolic patterns with outcome data in patients operated on for HS with or without CD.

Adolescent↗