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1.
J Chem Phys ; 140(6): 064304, 2014 Feb 14.
Article in English | MEDLINE | ID: mdl-24527912

ABSTRACT

Photoionization spectra and Rydberg-state-resolved threshold-ionization spectra of the gerade triplet np Rydberg states of (4)He2 located in the vicinity of the X(+) (2)Σ(u)(+) (ν(+) = 0) ionization threshold were recorded from the 2sσ a (3)Σ(u)(+) metastable state. An accuracy of 0.01 cm(-1) was achieved for the experimental term values of the observed Rydberg states. The data were combined with spectroscopic data on low-lying triplet np and nf Rydberg states from the literature to derive energy- and internuclear-distance-dependent eigenquantum-defect parameters of multichannel quantum-defect theory (MQDT). The MQDT calculations reproduce the experimental data within their experimental uncertainties and enabled the derivation of potential-energy curves for the lowest triplet p Rydberg states (n = 2-5) of He2. The eigenquantum-defect parameters describing the p -f interaction were found to be larger than 0.002 at the energies corresponding to the high-n Rydberg states, so that the p -f interaction plays an important role in the autoionization dynamics of np Rydberg states with v(+) = 0. By extrapolating the experimental term values of triplet np Rydberg states of (4)He2 in the range of principal quantum number n between 87 and 110, the positions of the (v(+) = 0, N(+) = 3) and (v(+) = 0, N(+) = 5) levels of the ground state of (4)He(+)(2) were determined to lie 70.937(3) cm(-1) and 198.369(6) cm(-1), respectively, above the (v(+) = 0, N(+) = 1) ground rotational level.

2.
Chimia (Aarau) ; 67(4): 257-61, 2013.
Article in English | MEDLINE | ID: mdl-23967701

ABSTRACT

Recent experiments are reviewed which have led to the determination of the ionization and dissociation energies of molecular hydrogen with a precision of 0.0007 cm(-)1 (8 mJ/mol or 20 MHz) using a procedure based on high-resolution spectroscopic measurements of high Rydberg states and the extrapolation of the Rydberg series to the ionization thresholds. Molecular hydrogen, with only two protons and two electrons, is the simplest molecule with which all aspects of a chemical bond, including electron correlation effects, can be studied. Highly precise values of its ionization and dissociation energies provide stringent tests of the precision of molecular quantum mechanics and of quantum-electrodynamics calculations in molecules. The comparison of experimental and theoretical values for these quantities enable one to quantify the contributions to a chemical bond that are neglected when making the Born-Oppenheimer approximation, i.e. adiabatic, nonadiabatic, relativistic, and radiative corrections. Ionization energies of a broad range of molecules can now be determined experimentally with high accuracy (i.e. about 0.01 cm(-1)). Calculations at similar accuracies are extremely challenging for systems containing more than two electrons. The combination of precision measurements of molecular ionization energies with highly accurateab initio calculations has the potential to provide, in future, fully reliable sets of thermochemical quantities for gas-phase reactions.


Subject(s)
Electrons , Heterocyclic Compounds/chemistry , Hydrogen/chemistry , Ions/chemistry , Quantum Theory , Thermodynamics
3.
Reprod Domest Anim ; 44(3): 411-3, 2009 Jun.
Article in English | MEDLINE | ID: mdl-18954389

ABSTRACT

To meet weekly breeding targets, it is occasionally necessary to inject exogenous gonadotrophins to induce oestrus in prepubertal gilts. However, the gilt oestrus response to equine chorionic gonadotrophin (eCG) either alone or in combination with human chorionic gonadotrophin (hCG) can be unpredictable. The objective of the present study was to examine possible reasons for this unpredictability. Prepubertal gilts (90 kg and 153 days of age, n = 109) received an injection of either 600 IU eCG or a combination of 400 IU eCG and 200 IU hCG (PG600), or were non-injected controls, and were then exposed to a mature boar for 15 min daily for 7 days for oestrus detection. At the time of injection, real-time ultrasound revealed that the gilt ovaries had primarily 1-2 mm follicles. Blood samples were obtained at time of hormone injection (day 0) and at days 3, 7 and 10 for assay of serum progesterone concentrations. The oestrus responses by 7 days were 15.5%, 73.3% and 0%, for eCG, PG600, and control gilts, respectively (p < 0.001). The oestrus response improved (p < 0.05) with increasing body weight. Based on circulating progesterone levels, all oestrous gilts ovulated except for four of the PG600 gilts. Failure to express oestrus in PG600 gilts was not associated with a premature rise in progesterone.


Subject(s)
Chorionic Gonadotropin/administration & dosage , Estrus/drug effects , Ovulation/drug effects , Sexual Maturation , Swine/physiology , Animals , Body Weight , Breeding , Drug Interactions , Female , Horses , Ovarian Follicle/diagnostic imaging , Progesterone/blood , Ultrasonography
4.
Reprod Domest Anim ; 44(3): 432-4, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19000224

ABSTRACT

To ensure sufficient numbers of pregnant females, particularly at hotter times of the year, hormonal induction of gilt oestrus may be necessary. However, the gilt oestrus and ovulation responses to gonadotrophin treatment have often proven unpredictable. The objective of this study was to examine possible reasons for this unpredictability. Prepubertal gilts (approximately 150 days of age, n = 63) were assigned to one of three treatments: injection of 300 IU hCG (n = 15); pre-treatment with 100 mg FSH in polyvinylpyrrolidinone administered as 2 x 50 mg injections 24 h apart, followed by 600 IU eCG at 24 h after the second FSH injection (n = 23); or FSH pre-treatment as above followed by 300 IU hCG at 24 h after the second FSH injection (n = 25). To facilitate oestrus detection, gilts were exposed to a mature boar for 15 min daily for 7 days. Blood samples were obtained on the day of eCG or hCG injection and again 10 days later and gilt ovulation responses determined based on elevated progesterone concentrations. The oestrus responses by 7 days were 6.7%, 17.5% and 64.0% for gilts treated with hCG, FSH + eCG and FSH + hCG, respectively (p < 0.001). The oestrous gilt receiving hCG alone and one oestrous FSH + hCG gilt did not ovulate, all other oestrous gilts ovulated. A further two anoestrous FSH + eCG-treated gilts ovulated. These data suggest that FSH pre-treatment facilitated the development of ovarian follicles to the point where they became responsive to hCG, but had little effect on the response to eCG.


Subject(s)
Chorionic Gonadotropin/administration & dosage , Estrus/drug effects , Follicle Stimulating Hormone/administration & dosage , Ovulation/drug effects , Swine/physiology , Animals , Female , Horses , Ovarian Follicle/drug effects , Ovarian Follicle/physiology , Progesterone , Sexual Maturation
5.
J Clin Invest ; 86(3): 688-95, 1990 Sep.
Article in English | MEDLINE | ID: mdl-2118552

ABSTRACT

This study characterized the plasma lipoproteins of familial hyperalphalipoproteinemic patients with or without deficiency of cholesteryl ester transfer protein (CETP) activity. The subjects with CETP deficiency have increased levels of apolipoprotein (apo) E. The increased concentration of apo E in these subjects was correlated to the appearance of apo E-rich high density lipoproteins (HDL). Sodium dodecyl sulfate-polyacrylamide gel analysis revealed that these lipoproteins contained predominantly the apo E (82%) and little amount of apo A-I (18%). These apo E-rich HDL displayed a much higher affinity than human LDL in binding to LDL receptors on human fibroblasts. Furthermore, 3.5 times fewer apo E-rich HDL than LDL were required to saturate the receptors on fibroblasts. These data indicated that the apo E-rich HDL in CETP-deficient human subjects contained multiple copies of apo E and bound to the LDL receptor through multiple interactions. The apo E-rich HDL, with similar properties as cholesterol-induced apo E HDLc, were not detectable in normal human subjects or in hyperalphalipoproteinemic subjects with normal CETP activity. The apo E-containing HDL in the latter subjects were smaller and contained only small amounts of apo E (14%). The difference in apo E-containing HDL in these subjects suggests a correlation between CETP level and the appearance of apo E-rich HDL.


Subject(s)
Apolipoproteins E/metabolism , Carrier Proteins/deficiency , Glycoproteins , Hyperlipoproteinemias/metabolism , Lipoproteins, HDL/metabolism , Apolipoprotein A-I , Apolipoproteins A/metabolism , Apolipoproteins B/metabolism , Cholesterol Ester Transfer Proteins , Humans , Molecular Weight , Receptors, LDL/metabolism
6.
J Clin Invest ; 88(3): 985-94, 1991 Sep.
Article in English | MEDLINE | ID: mdl-1885783

ABSTRACT

Our primary aim was to determine the extent to which intraplasmic retinyl palmitate (RP) transfers to other lipoprotein particles when chylomicron remnants are not produced and/or the plasma RP residence time is increased. The study was conducted on three familial type I hyperlipoproteinemic patients, four lipoprotein lipase (LpL)-deficient heterozygotes, and three controls on a metabolic research unit. To each subject, a fat load was administered containing 16% of total daily calories in type I patients, 40% in heterozygotes and controls, plus 60,000 U/m2 vitamin A. Triglyceride (TG) and RP levels were evaluated in chylomicron and nonchylomicron fractions. Delay in the clearance of chylomicron fraction RP and the marked deficiency in nonchylomicron-RP (presumed lack of remnant production) in all three type I patients suggests that RP does not demonstrate significant intraplasmic transfer from chylomicrons to existent apolipoprotein B100 particles. In contrast to noncoincident TG and RP peaking in the normal subject, heterozygotes were found to demonstrate coincident plasma TG and RP curves, which is consistent with a common catabolic pathway for both TG and RP and inconsistent with intraplasmic RP transfer. This corroborates reports on compromised chylomicron clearance in heterozygotes. We conclude that RP is an appropriate representative marker for intestinally derived particles in LpL-deficient or partially deficient individuals.


Subject(s)
Chylomicrons/metabolism , Hyperlipoproteinemia Type I/metabolism , Vitamin A/analogs & derivatives , Adolescent , Adult , Child , Child, Preschool , Diterpenes , Humans , Hyperlipoproteinemia Type I/genetics , Lipoproteins, LDL/metabolism , Male , Metabolic Clearance Rate , Middle Aged , Retinyl Esters , Triglycerides/blood , Vitamin A/metabolism
7.
J Clin Invest ; 77(2): 520-7, 1986 Feb.
Article in English | MEDLINE | ID: mdl-3944267

ABSTRACT

Two patients (brother and sister, 41 and 39 yr of age, respectively) have been shown to have marked elevation of plasma triglycerides and chylomicrons, decreased low density lipoproteins (LDL) and high density lipoproteins (HDL), a type I lipoprotein phenotype, and a deficiency of plasma apolipoprotein C-II (apo C-II). The male patient had a history of recurrent bouts of abdominal pain often accompanied by eruptive xanthomas. The female subject, identified by family screening, was asymptomatic. Hepatosplenomegaly was present in both subjects. Analytical and zonal ultracentrifugation revealed a marked increase in triglyceride-rich lipoproteins including chylomicrons and very low density lipoproteins, a reduction in LDL, and the presence of virtually only the HDL3 subfraction. LDL were heterogeneous with the major subfraction of a higher hydrated density than that observed in plasma lipoproteins of normal subjects. Apo C-II levels, quantitated by radioimmunoassay, were 0.13 mg/dl and 0.12 mg/dl, in the male and female proband, respectively. A variant of apo C-II (apo C-IIPadova) with lower apparent molecular weight and more acidic isoelectric point was identified in both probands by two-dimensional gel electrophoresis. The marked hypertriglyceridemia and elevation of triglyceride-rich lipoproteins were corrected by the infusion of normal plasma or the injection of a biologically active synthesized 44-79 amino acid residue peptide fragment of apo C-II. The reduction in plasma triglycerides after the injection of the synthetic apo C-II peptide persisted for 13-20 d. These results definitively established that the dyslipoproteinemia in this syndrome is due to a deficiency of normal apo C-II. A possible therapeutic role for replacement therapy of apo C-II by synthetic or recombinant apo C-II in those patients with severe hypertriglyceridemia and recurrent pancreatitis may be possible in the future.


Subject(s)
Apolipoproteins C/deficiency , Lipase/blood , Lipoproteins/blood , Triglycerides/blood , Adult , Apolipoprotein C-II , Apolipoproteins C/genetics , Apolipoproteins C/therapeutic use , Chylomicrons/blood , Female , Genetic Variation , Humans , Lipoproteins, HDL/blood , Lipoproteins, LDL/blood , Lipoproteins, VLDL/blood , Male
8.
J Thromb Haemost ; 15(6): 1095-1102, 2017 06.
Article in English | MEDLINE | ID: mdl-28339142

ABSTRACT

Essentials Antiangiogenic drugs are indicated as therapies for hereditary hemorrhagic telangiectasia. We interrogated the response to four antiangiogenic drugs for anemia and intestinal bleeding. Sorafenib and a pazopanib analog significantly improved while erlotinib worsened anemia. Some oral antiangiogenic drugs were effective in reducing intestinal bleeding. SUMMARY: Background Epistaxis and gastrointestinal (GI) tract hemorrhages are common symptoms of aged hereditary hemorrhagic telangiectasia (HHT) patients that result in anemia. Clinical as well as animal studies have suggested that vascular endothelial growth factor (VEGF) neutralizing antibodies lessen hemorrhage associated with adult-onset arteriovenous malformations (AVMs). Objectives The goal of this study is to evaluate potential therapeutic effects of oral delivery of four antiangiogenic tyrosine-kinase inhibitors (TKIs) in the development of adult-onset AVMs in a murine model of HHT. Methods An adult activin receptor-like kinase 1 (Alk1)-inducible knockout (iKO) model was utilized to evaluate the effect of oral administration of sorafenib, sunitinib, erlotinib and a pazopanib analog (GW771806) on hemoglobin level, GI hemorrhages and formation of wound-induced skin AVMs. Results and Conclusions Sorafenib and GW771806 significantly improved, yet erlotinib worsened, anemia and GI-bleeding in the Alk1-iKO model. However, none of these TKIs appeared to be effective for inhibiting the development of wound-induced skin AVMs. Taken together, these results suggest that oral delivery of antiangiogenic TKIs is selectively more effective for GI bleeding than mucocutaneous AVMs, and it may provide an experimental basis for selective therapeutic options depending on the symptoms of HHT.


Subject(s)
Angiogenesis Inhibitors/therapeutic use , Protein Kinase Inhibitors/therapeutic use , Telangiectasia, Hereditary Hemorrhagic/drug therapy , Telangiectasia, Hereditary Hemorrhagic/genetics , Activin Receptors, Type I/metabolism , Activin Receptors, Type II , Administration, Oral , Administration, Topical , Anemia/drug therapy , Anemia/genetics , Animals , Arteriovenous Malformations , Disease Models, Animal , Erlotinib Hydrochloride/administration & dosage , Gastrointestinal Hemorrhage , Hemoglobins/analysis , Image Processing, Computer-Assisted , Indazoles/administration & dosage , Mice , Mice, Knockout , Niacinamide/administration & dosage , Niacinamide/analogs & derivatives , Phenylurea Compounds/administration & dosage , Pyrimidines/administration & dosage , Skin/blood supply , Sorafenib , Sulfonamides/administration & dosage , Sulfones/administration & dosage , Tyrosine/chemistry , Vascular Endothelial Growth Factor A/metabolism , Wound Healing
9.
Biochim Biophys Acta ; 1005(3): 239-44, 1989 Oct 17.
Article in English | MEDLINE | ID: mdl-2804053

ABSTRACT

Apolipoprotein E (apoE) is important in the modulation of the catabolism of chylomicron and very low density lipoprotein (VLDL) remnants. ApoE has three major genetically determined isoproteins in plasma, designated apoE-2, apoE-3 and apoE-4, with homozygosity for the allele coding for apoE-2 being associated with dysbetalipoproteinemia or type III hyperlipoproteinemia (HLP). We describe a new variant of apoE, apoE-1Harrisburg, which is, in contrast to apoE-2, dominantly associated with type III HLP. Five of twelve members of the affected kindred are heterozygous for the mutant form of apoE, and four of the five have type III HLP, while the fifth member has dysbetalipoproteinemia on diet therapy. Neuraminidase digestion, which removes charged sialic acid residues, did not alter the electrophoretic position of the apoE-1Harrisburg isoprotein, indicating that the altered charge of apoE-1Harrisburg was not due to sialic acid addition to the apolipoprotein. Cysteamine modification, which adds a positively charged group to cysteine, resulted in a shift of apoE-1Harrisburg from the E-1 to the E-2 isoform position, indicating that there is one cysteine in apoE-1Harrisburg as is the case for apoE-3. These results are consistent with apoE-1Harrisburg originating in the allele for apoE-3 with the mutation leading to a negative two-unit charge shift. The definitive identification of a kindred with an apoE variant, apoE-1Harrisburg, dominantly associated with dysbetalipoproteinemia and type III HLP provides a unique opportunity to gain important insights into the structure-function requirements of the E apolipoprotein as well as the mechanisms by which apoE modulates lipoprotein metabolism.


Subject(s)
Apolipoproteins E/blood , Genetic Variation , Hyperlipoproteinemia Type III/blood , Adolescent , Adult , Aged , Apolipoproteins E/genetics , Apolipoproteins E/isolation & purification , Electrophoresis, Gel, Two-Dimensional , Electrophoresis, Polyacrylamide Gel , Female , Humans , Hyperlipoproteinemia Type III/genetics , Lipoproteins, VLDL/blood , Lipoproteins, VLDL/isolation & purification , Male , Middle Aged , Pedigree , Phenotype
10.
Biochim Biophys Acta ; 1485(2-3): 225-35, 2000 May 31.
Article in English | MEDLINE | ID: mdl-10832102

ABSTRACT

A family of extremely reactive electrophiles, isolevuglandins (isoLGs), is generated in vivo by free radical-induced lipid oxidation and rearrangement of endoperoxide intermediates of the isoprostane pathway. Protein adducts of two different oxidized lipids, isoLGE(2) and iso[4]LGE(2), and the corresponding autoantibodies are present in human blood. Western blot analysis of a polyacrylamide gel electrophoresis gel detects several immunoreactive plasma proteins. Only a minor fraction of the isoLG-protein modifications is associated with low density lipoprotein since mean levels were decreased only 20-22% by immunoprecipitation of apolipoprotein B (apoB). Mean levels of both isoLGE(2) and iso[4]LGE(2)-protein adducts in plasma from patients with atherosclerosis (AS) (n=16) or end-stage renal disease (RD) (n=8) are about twice those in healthy individuals (n=25). These elevated levels are not related to variations in age, total cholesterol or apoB. A linear correlation (r=0.79) between plasma isoLGE(2) and iso[4]LGE(2)-protein adduct levels in all 49 individuals is consistent with a common free radical-induced mechanism for the production of both oxidized lipids in vivo. The correlation is even stronger (r=0.86) for patients with AS or RD. That isoLG-protein adduct levels are more strongly correlated with disease than are total cholesterol or apoB suggests an independent defect that results in an abnormally high level of oxidative injury associated with AS and RD.


Subject(s)
Fatty Acids, Unsaturated/metabolism , Hemocyanins/metabolism , Prostaglandins E/metabolism , Prostaglandins H/metabolism , Adult , Animals , Apolipoproteins B/metabolism , Arteriosclerosis/blood , Autoantibodies/blood , Autoantibodies/immunology , Cholesterol/metabolism , Free Radicals , Humans , Kidney Failure, Chronic/blood , Lipid Metabolism , Middle Aged , Molecular Structure , Oxidation-Reduction , Prostaglandin H2 , Prostaglandins E/blood , Rabbits , Stereoisomerism
11.
Circulation ; 100(22): 2244-7, 1999 Nov 30.
Article in English | MEDLINE | ID: mdl-10577998

ABSTRACT

BACKGROUND: Traditional risk factors account for only half of the morbidity and mortality from coronary heart disease (CHD). There is substantial evidence that oxidative injury plays a major role in the atherosclerotic process. Thus, antioxidants may protect against development of atherosclerosis. Glutathione, an intracellular tripeptide with antioxidant properties, may be protective. METHODS AND RESULTS: This case-control study compared total serum glutathione (tGSH) in 81 adolescent male offspring of parents with premature CHD (ie, before 56 years of age) and 78 control male offspring of parents without known or suspected CHD. Case offspring had significantly lower tGSH than control offspring. In multiple logistic regression with parental CHD status as the dependent variable, age entered as a covariate, and other CHD risk factors competing to enter the model as significant independent predictor variables, LDL cholesterol (odds ratio [OR], 2.15 [units=1.5 SD]; 95% CI, 1.21 to 3.82), tGSH (OR, 0.40; 95% CI, 0.22 to 0.71), HDL cholesterol (OR, 0.42; 95% CI, 0.22 to 0.78), and total serum homocysteine (OR, 2.6; 95% CI, 1.35 to 5.02) entered the model as significant predictors of parental CHD status. CONCLUSIONS: Low tGSH in adolescent boys is a significant independent predictor of parental CHD, in addition to elevated LDL cholesterol, low HDL cholesterol, and elevated total serum homocysteine concentrations.


Subject(s)
Coronary Disease/epidemiology , Glutathione/blood , Adolescent , Aged , Anthropometry , Blood Pressure , Case-Control Studies , Cohort Studies , Coronary Artery Disease/blood , Coronary Artery Disease/epidemiology , Coronary Artery Disease/genetics , Coronary Disease/blood , Coronary Disease/genetics , Glutathione/deficiency , Homocysteine/blood , Humans , Lipids/blood , Logistic Models , Male , Middle Aged , Ohio/epidemiology , Oxidation-Reduction , Oxidative Stress , Parents , Sulfhydryl Compounds/blood
12.
Circulation ; 102(19 Suppl 3): III90-4, 2000 Nov 07.
Article in English | MEDLINE | ID: mdl-11082369

ABSTRACT

BACKGROUND: HDL cholesterol (HDL-C) is an important independent predictor of atherosclerosis, yet the role that HDL-C may play in the prediction of long-term survival after CABG remains unclear. The risk associated with a low HDL-C level in post-CABG men has not been delineated in relation to traditional surgical variables such as the use of arterial conduits, left ventricular function, and extent of disease. METHODS AND RESULTS: We performed a prospective, observational study of 432 men who underwent CABG between 1978 and 1979 in whom preoperative HDL-C values were available. Baseline lipid and lipoprotein values, history of diabetes mellitus and hypertension, left ventricular ejection fraction, extent of disease, and use of internal thoracic arteries were recorded. Hazard ratios (HRs) were determined in the patients with and without a low HDL-C level, which was defined as the lowest HDL-C quartile (HDL-C 35 mg/dL) were 50% more likely to survive at 15 years than were patients with low HDL-C level (35 mg/dL were 50% more likely to survive without a subsequent myocardial infarction or revascularization (HR 1.42, P:=0.02). CONCLUSIONS: HDL-C is an important predictor of survival in post-CABG patients. In this study of >8500 patient-years of follow-up, HDL-C was the most important metabolic predictor of post-CABG survival. One third fewer patients survive at 15 years if their HDL-C levels are

Subject(s)
Cholesterol, HDL/blood , Coronary Artery Bypass/methods , Coronary Disease/blood , Coronary Disease/mortality , Cohort Studies , Coronary Disease/surgery , Disease-Free Survival , Follow-Up Studies , Humans , Male , Middle Aged , Predictive Value of Tests , Prospective Studies , Risk Assessment , Survival Rate/trends
13.
Circulation ; 104(18): 2205-9, 2001 Oct 30.
Article in English | MEDLINE | ID: mdl-11684632

ABSTRACT

BACKGROUND: Recent studies have supported the hypothesis that calcific aortic stenosis is the product of an active inflammatory process, with similarities to atherosclerosis. We sought to determine whether therapy with hydroxymethylglutaryl coenzyme A reductase inhibitors (statins) might slow the progression of aortic stenosis. METHODS AND RESULTS: A retrospective study of 174 patients (mean age 68+/-12 years) with mild to moderate calcific aortic stenosis was conducted. Patients required normal left ventricular function, /=2 echocardiograms performed at least 12 months apart. Fifty-seven patients (33%) received treatment with a statin; the remaining 117 (67%) did not. The statin group was older and had a higher prevalence of hypertension, diabetes mellitus, and coronary disease. During a mean follow-up of 21 months, patients treated with statin had a smaller increase in peak and mean gradient and a smaller decrease in aortic valve area. When annualized, the decrease in aortic valve area for the nonstatin group was 0.11+/-0.18 cm(2) compared with 0.06+/-0.16 cm(2) for those treated with a statin (P=0.03). In multivariate analysis, statin usage was a significant independent predictor of a smaller decrease in valve area (P=0.01) and a lesser increase in peak gradient (P=0.02). CONCLUSIONS: Statin-treated patients, despite a higher risk profile for progression, had reduced aortic stenosis progression compared with those not treated with a statin. These data provide justification for a prospective randomized trial to substantiate whether statin therapy slows the progression of aortic stenosis.


Subject(s)
Aortic Valve Stenosis/drug therapy , Calcinosis/drug therapy , Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use , Aged , Aortic Valve Stenosis/complications , Aortic Valve Stenosis/diagnostic imaging , Atorvastatin , Calcinosis/complications , Calcinosis/diagnostic imaging , Cholesterol, HDL/blood , Cholesterol, LDL/blood , Disease Progression , Echocardiography , Electrocardiography/drug effects , Fatty Acids, Monounsaturated/therapeutic use , Female , Fluvastatin , Follow-Up Studies , Heptanoic Acids/therapeutic use , Humans , Indoles/therapeutic use , Lovastatin/therapeutic use , Male , Multivariate Analysis , Pravastatin/therapeutic use , Pyrroles/therapeutic use , Retrospective Studies , Risk Factors , Simvastatin/therapeutic use , Treatment Outcome , Triglycerides/blood , Vascular Patency/drug effects
14.
Circulation ; 104(24): 2886-91, 2001 Dec 11.
Article in English | MEDLINE | ID: mdl-11739301

ABSTRACT

BACKGROUND: Atrial fibrillation (AF) may persist due to structural changes in the atria that are promoted by inflammation. C-reactive protein (CRP), a marker of systemic inflammation, predicts cardiovascular events and stroke, a common sequela of AF. We hypothesized that CRP is elevated in patients with atrial arrhythmias. METHODS AND RESULTS: Using a case-control study design, CRP in 131 patients with atrial arrhythmias was compared with CRP in 71 control patients. Among arrhythmia patients, 6 had frequent atrial ectopy or tachycardia, 86 had paroxysmal AF, 39 had persistent AF lasting >30 days, and 70 had lone arrhythmias. CRP was higher in arrhythmia than in control patients (median, 0.21 versus 0.096 mg/dL; P<0.001). Arrhythmia patients in AF within 24 hours before sampling had higher CRP than those in sinus rhythm (0.30 versus 0.15 mg/dL; P<0.001). CRP in controls was not different than in patients with atrial ectopy or tachycardia. Lone arrhythmia patients had a CRP of 0.21 mg/dL, which was not significantly lower than arrhythmia patients with structural heart disease (CRP, 0.23 mg/dL) but higher than controls (P=0.002). Persistent AF patients had a higher CRP (0.34 mg/dL) than paroxysmal AF patients (0.18 mg/dL; P=0.008); both groups had higher CRP levels than controls (P

Subject(s)
Arrhythmias, Cardiac/metabolism , C-Reactive Protein/metabolism , Heart Atria/metabolism , Analysis of Variance , Atrial Fibrillation/metabolism , Case-Control Studies , Female , Heart Atria/physiopathology , Humans , Inflammation/metabolism , Male , Middle Aged
15.
J Am Coll Cardiol ; 36(4): 1159-65, 2000 Oct.
Article in English | MEDLINE | ID: mdl-11028465

ABSTRACT

OBJECTIVES: The aim of the study was to determine the value of a cluster of metabolic risk factors in predicting mortality after coronary artery bypass surgery (CABG). BACKGROUND: The "deadly quartet" of metabolic risk factors (i.e., obesity, diabetes, hypertension, and hypertriglyceridemia) has been associated with coronary heart disease in healthy population studies. The expected influence of the cluster on survival in secondary prevention remains untested overall as well as by gender. METHODS: Patients with lipid profiles undergoing primary isolated CABG (n = 6,428) between 1987 and 1992 were followed a median of eight years. Cox models were used to evaluate all-cause mortality. Metabolic risk factors were incorporated as the sum of deadly quartet risk factors present in each patient (0 to 4). The role of gender as it relates to survival and metabolic risk clusters was also examined. RESULTS: The sum of deadly quartet risk factors showed a significant relationship to mortality as the hazard ratio increased from 1.64 (confidence interval [CI] = 1.34-2.01) for one risk factor to 3.95 (2.73-5.69) for four risk factors. Annualized mortality ranged from 1% per year in patients with no risk factors to 3.3% per year in patients with all four risk factors. Within gender, the hazard ratio associated with four risk factors was 2.58 for men and 13.39 for women. The expected clustering of risk factors was 8% compared to the observed clustering of 10% in men and 21% in women. CONCLUSIONS: This cohort showed risk factor clustering beyond that expected due to chance, particularly in women. Even after revascularization, survival is diminished for patients with members of a family of metabolic risk factors at the time of surgery.


Subject(s)
Coronary Artery Bypass/mortality , Coronary Artery Disease/surgery , Diabetes Mellitus/mortality , Hypertension/mortality , Hypertriglyceridemia/mortality , Obesity/mortality , Aged , Cause of Death , Coronary Artery Disease/complications , Coronary Artery Disease/mortality , Diabetes Complications , Female , Hospital Mortality , Humans , Hypertension/complications , Hypertriglyceridemia/complications , Male , Middle Aged , Obesity/complications , Ohio/epidemiology , Proportional Hazards Models , Retrospective Studies , Risk Factors , Sex Factors , Survival Rate
16.
J Am Coll Cardiol ; 9(6): 1306-10, 1987 Jun.
Article in English | MEDLINE | ID: mdl-3294969

ABSTRACT

On the hypothesis that Doppler ultrasound fails to penetrate prosthetic valves, an in vitro flow simulation system was constructed in a large water tank. Conventional pulsed, continuous wave and Doppler color flow systems were used to detect flow in tubing placed diagonally within the water and maintained by a continuous pump. After control periods of flow detection within the tubing, six different prosthetic valves were interposed on a stage between the transducer and the tubing. In comparison with control measurements, detection of flow within the tubing was impossible when the Doppler beam traversed the central occluding ball of the Starr-Edwards Silastic prosthesis by any modality. Marked reduction in the detection of the Doppler signal was noted for the Starr-Edwards stellite prosthesis with only slight improvement in the ability to detect the flow signals through the central occluding discs of the Björk-Shiley, Hall-Kastor and St. Jude valves. In distinction to the other valves, the ability of Doppler ultrasound to detect flow behind the cusps of the Carpentier-Edwards heterograft was similar to that during the control period. An understanding of flow masking should improve the clinical utility of Doppler methods for investigating prosthetic valve dysfunction.


Subject(s)
Heart Valve Prosthesis , Ultrasonics/methods , Color , Evaluation Studies as Topic , Humans , Prosthesis Failure/diagnosis , Ultrasonics/standards , Ultrasonography/standards
17.
Anim Reprod Sci ; 87(1-2): 121-32, 2005 Jun.
Article in English | MEDLINE | ID: mdl-15885445

ABSTRACT

Insemination of sows with frozen-thawed spermatozoa results in lower fertility, in part due to spermatozoa having undergone a capacitation-like reaction. The present study employed chlortetracycline (CTC) staining analysis to investigate the effect of adding 20% (v/v) boar seminal plasma (SP) to boar spermatozoa on the temporal progress of capacitation and the acrosome reaction in spermatozoa cooled to 5 degrees C or incubated at 39 degrees C. Based on CTC staining patterns, seminal plasma appeared to reverse capacitation in spermatozoa that had undergone capacitation while incubated at 39 degrees C in a capacitation-supporting medium from 59.7 to 36.6% capacitated (P<0.001). Similarly, the addition of SP to boar spermatozoa cooled to 5 degrees C resulted in both the prevention of the capacitation-like reaction, and the reversal of an established capacitation-like reaction from 63.3 to 34.2% capacitated (P<0.001). These observations indicated that some constituent(s) of boar SP both prevent spermatozoa from undergoing capacitation as well as reverse capacitation in spermatozoa that have already undergone the process.


Subject(s)
Chlortetracycline , Cold Temperature , Semen Preservation/veterinary , Semen/physiology , Sperm Capacitation , Swine , Acrosome Reaction , Animals , Cell Survival , Male , Semen Preservation/methods , Spermatozoa/physiology , Staining and Labeling
18.
Diabetes Care ; 23(11): 1648-53, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11092287

ABSTRACT

OBJECTIVE: Hypertriglyceridemia is commonly observed in association with diabetes. Despite cross-sectional studies and isolated longitudinal analyses in patients without coronary artery disease, the suggestion that triglyceride levels are relevant to subsequent cardiovascular events in the setting of diabetes remains controversial. This study evaluates the predictive value of serum triglyceride levels on mortality in post-coronary artery bypass graft (CABG) diabetic patients with subsequent analysis by sex. RESEARCH DESIGN AND METHODS: This longitudinal observational study involving a large metropolitan hospital consists of 1,172 diabetic post-CABG patients (792 men and 380 women) with lipid data collected between the years 1982 and 1992. Cox proportional hazards regression models were used to estimate the risk of mortality and cardiac events associated with triglyceride levels in the highest quartile (> 2.90 mmol/l for men and > 3.12 mmol/l for women). RESULTS: Elevated preoperative serum triglyceride values in post-CABG subjects with diabetes were correlated with increased overall mortality (hazard ratio [HR] 1.26, 95% CI 1.00-1.59). The greatest influence of triglyceride levels was observed on overall (1.89, 1.30-2.73) and event-free survival (1.49, 1.06-2.08) in women. High triglyceride values were also modestly related to risk of cardiac events in diabetic men (1.28, 0.99-1.66). CONCLUSIONS: These data suggest that increased preoperative triglyceride levels predict increased late mortality and cardiac event risk in diabetic post-CABG patients, more strongly in women than in men.


Subject(s)
Coronary Artery Bypass , Coronary Disease/surgery , Diabetic Angiopathies/surgery , Triglycerides/blood , Cholesterol/blood , Cholesterol, HDL/blood , Coronary Artery Bypass/mortality , Coronary Disease/blood , Diabetic Angiopathies/blood , Disease-Free Survival , Female , Follow-Up Studies , Humans , Male , Middle Aged , Predictive Value of Tests , Proportional Hazards Models , Registries , Regression Analysis , Retrospective Studies , Sex Factors , Survival Rate , Time Factors
19.
Ann. intern. med ; 173(12): 989-1001, Dec. 15, 2020.
Article in English | BIGG | ID: biblio-1146660

ABSTRACT

Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant disease with an estimated prevalence of 1 in 5000 that is characterized by the presence of vascular malformations (VMs). These result in chronic bleeding, acute hemorrhage, and complications from shunting through VMs. The goal of the Second International HHT Guidelines process was to develop evidence-based consensus guidelines for the management and prevention of HHT-related symptoms and complications. The guidelines were developed using the AGREE II (Appraisal of Guidelines for Research and Evaluation II) framework and GRADE (Grading of Recommendations Assessment, Development and Evaluation) methodology. The guidelines expert panel included expert physicians (clinical and genetic) in HHT from 15 countries, guidelines methodologists, health care workers, health care administrators, patient advocacy representatives, and persons with HHT. During the preconference process, the expert panel generated clinically relevant questions in 6 priority topic areas. A systematic literature search was done in June 2019, and articles meeting a priori criteria were included to generate evidence tables, which were used as the basis for recommendation development. The expert panel subsequently convened during a guidelines conference to conduct a structured consensus process, during which recommendations reaching at least 80% consensus were discussed and approved. The expert panel generated and approved 6 new recommendations for each of the following 6 priority topic areas: epistaxis, gastrointestinal bleeding, anemia and iron deficiency, liver VMs, pediatric care, and pregnancy and delivery (36 total). The recommendations highlight new evidence in existing topics from the first International HHT Guidelines and provide guidance in 3 new areas: anemia, pediatrics, and pregnancy and delivery. These recommendations should facilitate implementation of key components of HHT care into clinical practice.


Subject(s)
Humans , Telangiectasia, Hereditary Hemorrhagic/genetics , Telangiectasia, Hereditary Hemorrhagic/prevention & control , Vascular Malformations/genetics , Epistaxis/prevention & control , Gastrointestinal Hemorrhage/prevention & control , Nasal Mucosa
20.
Clin Pharmacol Ther ; 36(4): 555-65, 1984 Oct.
Article in English | MEDLINE | ID: mdl-6383687

ABSTRACT

Neomycin, a nonabsorbable aminoglycoside antibiotic, has been shown to exert a hypocholesterolemic effect in man. In a 9-mo, double-blind, randomized, crossover, placebo-controlled clinical trial, the effect of neomycin, 2 gm/day, on plasma lipoproteins, as well as its safety, was described in 20 subjects with type II hyperlipoproteinemia. A 15% (50 mg%) decline in plasma cholesterol concentration was observed with neomycin. Most of this effect resulted from a 41 mg% (16%) decrease in low-density lipoprotein cholesterol concentration. No significant or consistent effect on the concentration of high-density lipoprotein cholesterol was observed. Monthly audiologic and renal evaluation disclosed no oto- or nephrotoxicity. Neomycin treatment in patients with type II hyperlipoproteinemia is an inexpensive and effective means of lowering the concentration of low-density lipoproteins and is free of significant side effects over a 3-mo period.


Subject(s)
Hyperlipoproteinemia Type II/drug therapy , Neomycin/therapeutic use , Adult , Analysis of Variance , Cholesterol, HDL/blood , Cholesterol, LDL/blood , Clinical Trials as Topic , Double-Blind Method , Female , Humans , Hyperlipoproteinemia Type II/diet therapy , Lipoproteins, VLDL/blood , Male , Middle Aged , Neomycin/blood , Prospective Studies , Random Allocation , Triglycerides/blood
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