Effect of neonatal hypoxia on the development of hepatic lipase in the rat

Increases in plasma lipids occur during hypoxia in suckling but not in weaned rats and may result from altered hepatic enzyme activity. We exposed rats to 7 days of hypoxia from birth to 7 days of age (suckling) or from 28 to 35 days of age (weaned at day 21). Hypoxia led to an increase in hepatic lipid content in the suckling rat only. Hepatic lipase was decreased to approximately 45% of control in 7-day-old rats exposed to hypoxia but not in hypoxic 35-day-old rats. Hypoxic suckling rats also had a 50% reduction in lactate dehydrogenase activity, whereas transaminase activity and CYP1A and CYP3A protein content were not different between hypoxic and normoxic groups. Additional rats were studied 7 and 14 days after recovery from hypoxic exposure from birth to 7 days of age; hepatic lipase activity had recovered to 85% by 7 days and to 100% by 14 days in the rats previously exposed to hypoxia. Administration of dexamethasone to neonatal rats to simulate the hyperglucocorticoid state found in hypoxic 7-day-old rats led to a moderate decrease ( approximately 75% of control) in hepatic lipases. Developmentally, in the normoxic state, hepatic lipases increased rapidly after birth and reached levels more than twofold that of the newborn by 7 days of age. Hypoxia delays the maturation of hepatic lipases. We suggest that the decrease in hepatic lipase activity contributes to hyperlipemia in the hypoxic newborn rats.

Comparison of the one-and-a-half-year results of closure of patent ductus arteriosus by transcatheter coils placement with surgical ligation

Patent ductus arteriosus (PDA) is a common type of congenital cardiovascular lesion. It usually needs surgical ligation in a full-term baby after 1 year of age. Transcatheter implantation of coils was introduced for the closure of small- to moderate-sized PDA in 1992. From November 1995 to November 1998, the authors closed the PDA in 153 patients by transcatheter implantation of coils and by surgical ligation in 10 patients. One hundred fourteen of them were studied for more than 1(1/2) years. The regular follow-up studies, including physical examination; electrocardiography; and pulsed, continuous-wave, and color Doppler flow mapping, were performed on day one and day 2, and 1 week, 1 month, 3 months, 6 months, and 1 year after the procedure. The results of the closure of PDA by surgical ligation or coil placement were compared and analyzed in all the patients.

Transcatheter stent treatment for congenital peripheral pulmonary arterial stenosis

A total of 5 Johnson and Johnson stents were implanted in two patients with significant residual peripheral pulmonary arterial stenosis. These were a 15-year-old boy with post-open heart surgery for tetralogy of Fallot and a 3 8/12 year-old boy with D-transposition of great vessels. Immediately after balloon dilatation and implantation of the stents, the diameter of the narrowing pulmonary arteries increased significantly from 6.0 +/- 0.8 mm to 13.5 +/- 1.7 mm (P < 0.001) and the systolic pressure gradients across the stenosis of peripheral pulmonary artery dropped significantly from 33.0 +/- 16.0 mmHg to 10.2 +/- 4.4 mmHg (P < 0.01). One year later, repeated cardiac catheterization was performed on both patients. In the patient with tetralogy of Fallot, a 20 mmHg pressure gradient was found between the main and left pulmonary artery. This patient then received another stent implantation to release the residual stenosis. The boy with D-transposition of great vessels had only 9 mmHg gradient between main and right pulmonary artery. Transcatheter placement of the stent is a feasible and effective method to treat certain patients with significant pulmonary arterial stenosis if surgical correction can not be performed.

Modulation of rat epididymal gamma-glutamyl transpeptidase by nonylphenols

1. gamma-Glutamyl-transpeptidase (gamma-GTP), present at low levels in the testis, seminal vesicle, prostate gland and epididymis in rat at 4 days of age, showed rapid developmental increases at the time of weaning. 2. Administration of nonylphenols (NP) to the neonatal male rat pup (from days 1 to 15) impaired the subsequent development of gamma-GTP in the epididymis but not in the testis, seminal vesicles or prostate gland. 3. Single injection of NP to weaned pups at approximately 22 days of age decreased gamma-GTP in the epididymis but not in other male accessory sex organs. This effect was transient, dose-dependent and blocked by the oestrogen receptor-specific antagonist ICI 182,780. 4. Single injection of oestradiol to weaned rat at approximately 22 days of age also decreased gamma-GTP in the epididymis but not in the testis, prostate gland or seminal vesicles. 5. In in vitro assays, NP did not inhibit epididymal gamma-GTP activity even at 100 microM final concentration. Under similar conditions, acivicin, a specific inhibitor for gamma-GTP, showed a dose-dependent inhibition of gamma-GTP activity. 6. It is suggested that NP impair gamma-GTP expression in the epididymis of developing male rat and act in part via the oestrogen receptor.

Sauropus androgynus and papaverine do not induce bronchiolitis obliterans in Sprague-Dawley rats

BACKGROUND

In August 1995, an outbreak of bronchiolitis obliterans was observed in Taiwan. This progressive respiratory distress disease was associated with consumption of the uncooked vegetable, Sauropus androgynus. The vegetable is reportedly high in papaverine, a chemical that affects vasodilatation. This study determined whether S androgynus and papaverine induce bronchiolitis obliterans in Sprague-Dawley (S/D) rats.

METHODS

The feeding doses were derived from the mean amount (in mg/kg body weight) that humans had eaten. In part A of the experiment, 30 S/D rats were fed various concentrations of S androgynus juice for eight weeks. The rats were divided into six groups, including a normal control and study groups with one time (1X), 10 times (10X, leaf only and mixed leaf and stalk) and 30 times (30X, leaf only and mixed leaf and stalk) concentration. In part B, 33 S/D rats were fed different doses of papaverine for 4 weeks. The rats were also divided into six groups, including normal control, oral feeding subgroups (1X, 10X and 20X) and intraperitoneal injection subgroups (5X and 10X). The degree of inflammation was defined semiquantitatively in the bronchioles and pulmonary vessel adventitia as including grade 0 (no inflammation), grade 1 (minimal), grade 2 (mild), grade 3 (moderate) and grade 4 (severe).

RESULTS

There was no evidence of bronchiolitis obliterans in either experiment. The histopathologic findings of the lungs revealed normal or only minimal inflammatory changes in the peribronchial and perivascular adventitia in each group of both studies. The mean degree of inflammatory changes in the study groups was no different from that of control group.

CONCLUSIONS

We conclude that ingestion of high-dose S anggogynus and papaverine do not induce injuries to the airways, alveoli or pulmonary vessels in the animal model of S/D rats. The species barrier may be one of the possible reasons.

Transcatheter closure of atrial septal defect with a CardioSEAL device

Transcatheter closure of an interatrial septal defect (ASD) with a CardioSEAL device was successfully performed on 12 Taiwanese children. There were five boys and seven girls, aged from 3.6-13.9 (8.3+/-3.2) years and with body weight of 15-57 (33.7+/-14.7) kgs. After one year of follow-up studies, which included physical examination, ECG, chest X-ray and echocardiography, complete closure of ASD was achieved in nine (75%) patients. Two children with a trivial residual shunt were asymptomatic and without audible cardiac murmur. A girl had a small residual left to right atrial shunt by color Doppler echocardiography, but without audible cardiac murmur. There were no immediate or intermediate complications. Transcatheter implantation of the CardioSEAL device is a safe and proper treatment for children with non-complicated small to medium secundum ASD.

Positron emission tomography for the assessment of myocardial viability in Kawasaki disease using different therapies

13N-ammonia and 18F-fluorodeoxyglucose positron emission tomography (PET) of the heart were performed on 30 children with a history of Kawasaki disease. The results indicated PET abnormalities in 61.1% of patients during the acute and subacute stages and in 41.2% of patients in the convalescent stage of Kawasaki disease. Two-dimensional echocardiography and coronary angiography could not predict the myocardial viability and perfusion as well as PET. Different therapies during the acute stage of the disease did not effectively prevent myocardial damage, despite the absence of coronary arterial abnormalities. The patients who received 400 mg x kg(-1) x day(-1) of intravenous immunoglobulin (IVIG) for 5 days had a significantly lower incidence of PET abnormalities than those who received a single dose of 2000 mg x kg(-1) IVIG (P < 0.05).

Batch and continuous cultivation of Anaerobiospirillum succiniciproducens for the production of succinic acid from whey

Batch and continuous cultivation of Anaerobiospirillum succiniciproducens were systematically studied for the production of succinic acid from whey. Addition of 2.5 g l(-1) yeast extract and 2.5 g l(-1) polypeptone per 10 g l(-1) whey was most effective for succinic acid production from both treated and nontreated whey. When 20 g l(-1) nontreated whey and 7 g l(-1) glucose were used as cosubstrates, the yield and productivity of succinic acid reached at the end of fermentation were 95% and 0.46 g (1 h)(-1), respectively. These values were higher than those obtained using nontreated whey alone [93% and 0.24 g (1 h)(-1) for 20 g l(-1) whey]. Continuous fermentation of A. succiniciproducens at an optimal dilution rate resulted in the production of succinic acid with high productivity [1.35 g (1 h)(-1)], high conversion yield (93%), and higher ratio of succinic acid to acetic acid (5.1:1) from nontreated whey.

Attenuation of myocardial ischemia/reperfusion injury by superinduction of inducible nitric oxide synthase

BACKGROUND

Nitric oxide (NO) has been implicated as a mediator in myocardial ischemia/reperfusion (I/R) injury, but its functional properties have been conflicting. We investigated whether NO has a protective role against I/R injury.

METHODS AND RESULTS

Using endothelial NO synthase knockout (eNOS KO) mice, inducible NOS KO mice, the NO donor S-nitroso-N-acetylpenicillamine (SNAP), and the NOS inhibitor N-iminoethyl-L-ornithine (L-NIO), we performed studies of isolated perfused hearts subjected to 30 minutes of global ischemia followed by reperfusion. After 60 minutes of reperfusion, nitrite levels in the coronary effluent in the SNAP and eNOS KO groups were significantly elevated compared with other groups. Immunoblot and immunohistochemistry showed that iNOS was markedly induced in the eNOS KO hearts. Under spontaneous beating conditions during reperfusion, increased NO activity was correlated with a prevention of the hyperdynamic contractile response and enhanced myocardial protection, as evidenced by a reduction in myocardial injury and infarct size. During prolonged reperfusion, SNAP-treated hearts were able to preserve contractile functions for 180 minutes, whereas L-NIO-treated hearts showed a sustained deterioration in contractility.

CONCLUSIONS

NO protects against I/R injury by preventing the hyperdynamic response of isolated perfused hearts during early reperfusion. In the eNOS KO hearts, a paradoxical increase in NO production was seen, accompanied by a superinduction of iNOS, possibly due to an adaptive mechanism.

Effectiveness of an organ-sharing program in providing zero HLA-A,B,DR mismatched kidneys for transplantation in Taiwan

PURPOSE

This study evaluated the effects of organ sharing on the allocation of kidneys from cadaveric donors to uremic patients from National Cheng Kung University Hospital (CKUH) and National Taiwan University Hospital (NTUH) who were waiting for kidney transplantation.

METHODS

Standard complement-dependent microcytotoxicity assays were used. Human leukocyte antigen (HLA)-A,B,C typing was performed on nylon-wool-enriched T lymphocytes. HLA-DR typing was performed on either nylon-wool-separated B cells or Dynabeads. Isolation of class II-positive cells was performed with commercial typing trays.

RESULTS

Organs were allocated from a total of 88 cadaveric donors to 320 patients treated at CKUH and 179 patients treated at NTUH. Cadaveric kidneys could be allocated with an A,B,DR mismatch to 6.9% of CKUH patients and to 4.7% of NTUH patients. When CKUH and NTUH patients were pooled, the total number of kidneys that could be allocated with 0-A,B,DR mismatch increased to 13.3% (p < 0.004). However, when allocation was assessed using 10,000 potential bone marrow donors instead of the 88 cadaveric donors, kidneys could have been allocated with 0-A,B,DR mismatch to 12% (p = 0.64) of patients. No significant benefit was found when allocation estimates from the 10,000 potential bone marrow donors were compared with those for the 88 cadaveric donors. Use of epitope matching resulted in a 0-A,B cross-reactive epitope group, and a 0-DR mismatch allocation rate of 36.4% in CKUH patients and 31.8% in NTUH patients. This rate increased to 54.6% (p < 0.001) when the patients from these hospitals were pooled.

CONCLUSION

The results of this study demonstrate that the pooling of patients among regional transplant centers in Taiwan can significantly enhance the benefits of an organ donation program through better HLA matching.

Factors predictive of liver cirrhosis in patients with chronic hepatitis B: a multivariate analysis in a longitudinal study

OBJECTIVE AND DESIGN

Chronic hepatitis B virus (HBV) infection may lead to liver cirrhosis; however, factors associated with the development of cirrhosis have been incompletely studied. A total of 516 patients with chronic hepatitis B were followed up longitudinally to determine their outcome.

METHODS

The clinical and pathological features were compared between those with and without cirrhosis occurrence. The risk factors were analysed, and the probability of the development of cirrhosis was estimated.

RESULTS

During a mean follow-up period of 5.7 +/- 3.4 years (range 1-17 years), cirrhosis occurred in 71 patients, with a calculated annual incidence of 2.4%. Older age (> 45 years) at entry, male gender, persistent hepatitis (> 1.5-fold rise of serum alanine aminotransferase levels for at least one year) and diabetes mellitus were identified as independent risk factors of cirrhosis in a multivariate analysis (odds ratios 8.0, 19.3, 2.0 and 5.2, respectively; P values all < 0.05). A logistic regression equation was used to predict the probability of cirrhosis occurrence, which was as high as 76.6% when all risk factors were present. Acute exacerbation or super-infection by hepatitis C or D viruses were not significant predictors. Patients with subsequent cirrhosis had higher initial hepatic histological necro-inflammatory activities when compared to age- and sex-matched non-cirrhotic controls (Knodell's scores: 8.2 +/- 2.4 versus 6.0 +/- 4.1, P< 0.05).

CONCLUSIONS

Patients who were elderly, male, diabetic or had a history of persistent and histologically severe hepatitis were at increased risks of liver cirrhosis. Aggressive anti-viral therapy may be needed for these patients and they should be closely monitored for HBV-related late complications.

Comparison of 201Tl SPET and treadmill exercise testing in patients with Kawasaki disease

About 4% of children with Kawasaki disease ultimately develop ischaemic heart disease. Therefore, the early detection, non-invasive monitoring and long-term follow-up of myocardial ischaemia are essential. We compared the sensitivity and specificity of 201Tl single photon emission tomography (SPET) and treadmill exercise in the detection of myocardial ischaemia in 23 patients (19 boys, 4 girls) with Kawasaki disease. They were divided into two groups according to the results of coronary angiography. Group I consisted of 11 patients with coronary abnormalities; Group II consisted of 12 patients with no coronary abnormalities. The sensitivity, specificity, false-positive and false-negative rates for detecting coronary arterial lesions were 72.7% (8/11), 58.3% (7/12), 38.5% (5/13) and 30% (3/10) for 201Tl SPET, and 45.5% (5/11), 100% (12/12), 0% (0/5) and 33.3% (6/18) for treadmill exercise, respectively. We conclude that 201Tl SPET is more sensitive than treadmill exercise for the detection of coronary arterial abnormalities, but that the specificity of treadmill exercise is better than that of 201Tl scintigraphy. Coronary artery lesions detected by coronary angiography have good concordance of ischaemic areas with perfusion defects detected by 201Tl SPET. When ischaemic findings on 201Tl SPET and/or positive treadmill exercise testing are noted, coronary angiography is strongly indicated to detect possible stenotic lesions in the coronary arteries.

Prevalence and risk factor analysis of TTV infection in prostitutes

TTV, a DNA virus, has been isolated from patients with non-A to non-E post-transfusion hepatitis. In the past it was assumed that TTV was transmitted parenterally. It is unclear whether sexual contact leads to transmission of this virus. In this study, two sets of TTV-specific polymerase chain reaction primers were used to detect serum TTV DNA in 140 prostitutes and 136 controls. The prevalence of TTV DNA in prostitutes was significantly higher than in the control group (46/140 [32.9%] vs. 29/136 [21.3%]; P = 0.043). There was no significant difference in the prevalence of positive antibody to hepatitis A virus (anti-HAV) in either group (87.8% for prostitutes, 85.3% for controls). No particular risk factor was significantly associated with positive TTV DNA in prostitutes. In summary, TTV is highly prevalent in prostitutes. Transmission of TTV via sexual contact is not as efficient as transmission of hepatitis C and D viruses and GB virus-C hepatitis G virus. The high prevalence of TTV in controls indicates that there are diverse routes of transmission of this virus.

Potent and selective activity of a combination of thymidine and 1843U89, a folate-based thymidylate synthase inhibitor, against Plasmodium falciparum

Unlike mammalian cells, malarial parasites are completely dependent on the de novo pyrimidine pathway and lack the enzymes to salvage preformed pyrimidines. In the present study, first, it is shown that 1843U89, even without polyglutamylation, is a potent folate-based inhibitor of purified malarial parasite thymidylate synthase. The binding was noncompetitive with respect to methylenetetrahydrofolate, and 1843U89 had a K(i) of 1 nM. The compound also had potent antimalarial activity in vitro. Plasmodium falciparum cells in culture were inhibited by 1843U89, with a 50% inhibitory concentration of about 70 nM. The compound was effective against drug-sensitive as well as drug-resistant clones of P. falciparum. As predicted by the biochemistry of the parasite, the potent inhibition of parasite proliferation by 1843U89 could not be reversed with 10 microM thymidine. In contrast, in the presence of 10 microM thymidine, mammalian cells were unaffected by 1843U89 even at concentrations as high as 0.1 mM, thus offering a selectivity window of more than 1,000-fold. On this basis, folate-based thymidylate synthase inhibitors may represent a powerful additional tool that can be used to combat drug-resistant malaria.

Diabetes mellitus as a risk factor of liver cirrhosis in patients with chronic hepatitis B virus infection

Liver cirrhosis may occur in chronic hepatitis B surface antigen (HBsAg) carriers. Diabetes mellitus (DM)-associated chronic hepatitis may also occasionally lead to cirrhosis; however, its role in the course of chronic HBsAg carriers has not been studied. A cohort of 500 HBsAg carriers (398 men; mean age at entry, 42 +/- 15 years) were followed up longitudinally. After a mean follow-up of 5.8 +/- 3.3 years, 71 (14.2%: 70 men) patients developed cirrhosis. Increased risks of cirrhosis were found among men and the elderly (p < 0.001). Fifteen (21.1%) cirrhotic patients were noted to have had DM for 2-15 years before the development of cirrhosis. By contrast, only eight (1.9%; p < 0.001 ) of the patients without cirrhosis developed DM. When cirrhotic patients were compared to 102 age- and sex-matched non-cirrhotic controls, DM and elevation of serum alanine transaminase levels were found to be independent factors associated with the advent of cirrhosis in multivariate analysis. Other factors, including acute exacerbation, bridging hepatic necrosis, and superinfection by hepatitis C or D viruses, were insignificant. Our results suggest that DM may play a role in the progression to liver cirrhosis in chronic HBsAg carriers. High-risk subjects should be closely monitored for late complications.

Prevalence and risk factor analysis of TTV infection in prostitutes

TTV, a DNA virus, has been isolated from patients with non-A to non-E post-transfusion hepatitis. In the past it was assumed that TTV was transmitted parenterally. It is unclear whether sexual contact leads to transmission of this virus. In this study, two sets of TTV-specific polymerase chain reaction primers were used to detect serum TTV DNA in 140 prostitutes and 136 controls. The prevalence of TTV DNA in prostitutes was significantly higher than in the control group (46/140 [32.9%] vs. 29/136 [21.3%]; P = 0.043). There was no significant difference in the prevalence of positive antibody to hepatitis A virus (anti-HAV) in either group (87.8% for prostitutes, 85.3% for controls). No particular risk factor was significantly associated with positive TTV DNA in prostitutes. In summary, TTV is highly prevalent in prostitutes. Transmission of TTV via sexual contact is not as efficient as transmission of hepatitis C and D viruses and GB virus-C hepatitis G virus. The high prevalence of TTV in controls indicates that there are diverse routes of transmission of this virus.

Endothelial nitric oxide synthase protects aortic allografts from the development of transplant arteriosclerosis

BACKGROUND

Inducible nitric oxide synthase (iNOS) is up-regulated in rejecting allografts and is protective against allograft arteriosclerosis; it suppresses neointimal smooth muscle cell accumulation and inhibits adhesion of platelets and leukocytes to the endothelium. However, the functional importance of endothelial NOS (eNOS) in the rejecting allografts remains unclear.

METHODS

We examined the effects of selective eNOS deficiency in aortic allografts in a murine chronic rejection model using grafts from eNOS knockout (KO) mice (C57BL/6 background; H2b) and normal C3H (H2K) as recipients. Grafts from wild-type C57BL/6 mice served as controls. Grafts from iNOS KO mice served as a second group of controls where the contribution from iNOS was eliminated but eNOS was preserved. Aortic grafts were harvested and analyzed at days 10-14, 18-22, and 26-30 after transplantation.

RESULTS

Endothelial NOS-deficient grafts showed significantly increased intima/media ratios at days 26-30 compared to controls. Immunostaining demonstrated that in eNOS KO grafts, eNOS was not detectable whereas iNOS was expressed prominently in infiltrating recipient mononuclear cells. In control grafts, eNOS expression was preserved in the endothelium even by day 30, and associated with a decrease in intimal thickening. We further demonstrated that early overexpression of iNOS by ex vivo gene transfer completely prevented the development of arteriosclerosis associated with eNOS deficiency.

CONCLUSIONS

We found that eNOS plays a protective role in allografts, and that in eNOS-deficient allografts, early overexpression of iNOS is capable of preventing the development of allograft arteriosclerosis. In allografts with dysfunctional vascular endothelium and impaired eNOS activity as a result of ischemia or native arteriosclerotic disease, iNOS gene therapy may serve to improve their long-term survival and function.

Comparisons of a proposed five-seed assay method with the single-seed and batch assay methods for I-125 seeds in ultrasound-guided prostate implants

A simple five-seed assay method was proposed and investigated. A commercial well ion chamber system with an NIST-traceable single-seed calibration constant was used for the single-seed assays. A batch seed holder was used for batch assays. For the five-seed assays, a second single-seed holder was modified such that all five seeds were loaded in a central region of the well ion chamber. Compared with the same seed in the standard single-seed holder, the relative chamber responses for the five seed positions were 0.993, 0.993, 1.000, 1.001, and 0.977, respectively, indicating little or no position-dependent chamber response and no self-attenuation among seeds. Subsequent comparison of assays with the single-seed and five-seed methods indicated only 0.4% difference in charge collection. The five-seed calibration constant was therefore taken to be the same as the single-seed calibration constant. The reproducibility of the five-seed assay method was found to be better than 0.8%. When a dummy seed replaced an active seed, a nearly 20% reduction in charge was found, indicating that the proposed five-seed assay method can detect a dead seed. Clinical comparison of all three assay methods showed that they produced qualitatively the same assay results when the batch assay method was performed with extra care. Compared with the single-seed assay method, the five-seed method is equally simple, rigid, and reproducible, but it demands much less assay time. Compared with the batch assay method, the five-seed method is much more reproducible and reliable because of its rigid assay geometry; it only demands a moderate amount of assay time and can detect dead seeds. The American Association of Physicists in Medicine Task Group 40 (AAPM TG40) states that, for brachytherapy, ideally every (i.e., 100%) loose seed should be calibrated. For procedures involving large number of loose seeds, it then recommends that 10% of seeds be calibrated. The proposed five-seed assay is very simple to implement. It will facilitate the compliance of the "10%" recommendation from the AAPM TG40; it will make the "ideally 100%" statement from AAPM TG40 a more realistic and practical QA procedure in seed assaying.

Endothelial dysfunction in patients with heart failure: relationship to disease severity

BACKGROUND

Heart failure is associated with abnormal endothelium-dependent vasodilation. However, the relationship of this abnormality to heart failure severity has not been well defined.

METHODS AND RESULTS

We used strain-gauge plethysmography to assess forearm blood flow (FBF) responses to endothelium-dependent, endothelium-independent, and reactive hyperemic stimuli in normal subjects (n = 29) and in patients with mild (n = 26) and severe (n = 41) heart failure. FBF responses to intra-arterial methacholine (0.3, 1.5, 3.0 microg/min) were significantly (P < .005) and similarly reduced in patients with mild (2.8 +/- 0.4, 5.9 +/- 0.7, and 7.7 +/- 1.1 mL/min/dL) and severe (2.7 +/- 0.4, 5.4 +/- 0.7, and 6.9 +/- 0.9) heart failure compared with normal subjects (4.5 +/- 0.4, 9.4 +/- 1.0, and 12.0 +/- 1.1). FBF responses to nitroprusside (1, 5, 10 microg/min) were significantly reduced in mild (2.4 +/- 0.3, 6.7 +/- 1.1, and 11.9 +/- 2.0, P < .05) and severe (1.9 +/- 0.2, 5.1 +/- 0.5, and 7.3 +/- 0.9, P < .001) heart failure groups compared with normal subjects (3.8 +/- 0.5, 10.8 +/- 1.2, and 14.9 +/- 1.2). However, FBF responses were reduced to a greater extent (P < .001) in mild heart failure compared with severe heart failure. Peak reactive hyperemia was significantly impaired only in severe heart failure. There was no correlation between methacholine responses and ejection fraction, maximum oxygen consumption, wedge pressure, or serum norepinephrine.

CONCLUSION

Impaired endothelium-dependent vasodilation is present and near maximum in mild heart failure. Endothelial dysfunction may be an early finding in human heart failure.

MicroStructured Omnifit acetabular components: concerns with locking system complications and excessive polyethylene wear

BACKGROUND

We began to use cementless MicroStructured Omnifit acetabular components in November 1988. Liner dislodging and excessive polyethylene wear later occurred in some of our patients. This finding prompted us to review our experience with the use of such modular acetabular components.

METHODS

A total of 887 hips in 672 patients, which had been fitted with cementless MicroStructured Omnifit acetabular components, were evaluated for locking system complications using radiographic examinations. Of the cases, 240 hips which had received a 26-mm femoral head (group 1) and 110 hips which had received a 32-mm femoral head (group 2) were compared using a digitiser to determine the influence of femoral head size on polyethylene wear.

RESULTS

There were two types of radiographic signs of locking system complications in 7 hips, at a mean time of 2.9 years after implantation. The incidence of liner locking system complications using this modular acetabular component was 0.8%. The mean liner wear rate per year was 0.15 mm in group 1 and 0.20 mm in group 2 (p <0.005). The initial polyethylene thickness ranged from 5.9 to 13.6 mm in group 1, compared with 3.9 to 10.6 mm in group 2 (p < 0.005).

CONCLUSION

A patient who has received a total hip arthroplasty that includes a MicroStructured Omnifit acetabular component should be monitored frequently for radiographic signs of locking system complications. In this study, the mean liner wear rate was significantly higher in group 2. Inadequate polyethylene thickness in this group was implicated as the major cause of excessive polyethylene wear.

Evaluation of linkage of markers on chromosome 6p with schizophrenia in Taiwanese families

Previous studies have indicated possible linkage of schizophrenia with chromosome 6p21-24. In an attempt to replicate these findings, we studied the linkage of schizophrenia with nine markers on chromosome 6p21-24 in 39 Taiwanese schizophrenic nuclear families with at least two affected siblings. Two diagnostic models (narrow: Diagnostic and Statistical Manual of Mental Disorders-IV schizophrenia only; and broad: including schizophrenia, schizoaffective, and other nonaffective psychotic disorders) were used to define the disease phenotypes. With the broad and narrow diagnostic models, the marker D6S296 produced maximum two-point lod scores of 1.46 (straight theta = 0.2) and 1.35 (straight theta = 0. 2), respectively, in the recessive inheritance model. Assuming locus heterogeneity, a multipoint lod score of 0.85 was obtained between markers D6S296 and D6S277 under the narrow/recessive model. Maximum nonparametric lod scores of 1.25 ( p= 0.09) and 1.36 (p = 0.08) were observed, but still not statistically significant, at D6S296 in the narrow and broad diagnostic models, respectively. Both two-point analysis of the dominant model (lod score 0.85) and nonparametric analysis (lod score 1.25) showed a mild peak lod score appeared at marker D6S 285 as well. The results add some support to the suggestive linkage of schizophrenia with markers in the regions of chromosome 6p22 and 6p24 in an ethnically distinct Taiwanese sample. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 96:74-78, 2000.