Determinants of V̇+O2peak Changes After Aerobic Training in Coronary Heart Disease Patients

This study aimed to highlight the ventilatory and circulatory determinants of changes in ˙VO2peak after exercise-based cardiac rehabilitation (ECR) in patients with coronary heart disease (CHD). Eighty-two CHD patients performed, before and after a 3-month ECR, a cardiopulmonary exercise testing (CPET) on a bike with gas exchanges measurements (˙VO2peak, minute ventilation, i. e., ˙VE), and cardiac output (Q˙c). The arteriovenous difference in O2 (C(a-v¯)O2) and the alveolar capillary gradient in O2 (PAi-aO2) were calculated using Fick's laws. Oxygen uptake efficiency slope (OUES) was calculated. A 5.0% cut off was applied for differentiating non- (NR: ˙VO2<0.0%), low (LR: 0.0≤ ∆˙VO2<5.0%), moderate (MR: 5.0≤∆˙VO2 < 10.0%), and high responders (HR: ∆˙VO2≥10.0%) to ECR. A total of 44% of patients were HR (n=36), 20% MR (n=16), 23% LR (n=19), and 13% NR (n=11). For HR, the ˙VO2peak increase (p<0.01) was associated with increases in ˙VE (+12.8±13.0 L/min, p<0.01), (+1.0±0.9 L/min, p<0.01), and C(a-v¯)O2 (+2.3±2.5 mLO2/100 mL, p<0.01). MR patients were characterized by+6.7±19.7 L/min increase in ˙VE (p=0.04) and+0.7±1.0 L/min of Q˙c (p<0.01). ECR induced decreases in ˙VE (p=0.04) and C(a-v¯)O2 (p<0.01) and a Q˙c increase in LR and NR patients (p<0.01). Peripheral and ventilatory responses more than central adaptations could be responsible for the ˙VO2peak change with ECR in CHD patients.

Does a three-hour delayed pushing benefit the mode of delivery?

OBJECTIVE

The objective of this study was to compare two strategies for passive second stage management: three-hour vs two-hour delayed pushing after the diagnosis of full cervical dilation on mode of delivery and perinatal outcomes.

STUDY DESIGN

This retrospective observational study included low-risk nulliparous women who reatched full cervical dilation under epidural analgesia with a single term fetus in cephalic presentation and normal fetal heart rate, between September and December 2016. Mode of delivery (spontaneous vaginal delivery versus operative delivery including cesarean section and instrumental vaginal delivery) and perinatal outcomes (post-partum hemorrhage, perineal lacerations, 5-min Apgar score, umbilical cord pH and transfer to neonatal intensive care unit) were compared between two maternity units: maternity unit A, where women could have up to a three-hour delayed pushing period after full cervical dilation diagnosis, and maternity unit B, where the delayed pushing period was a maximum of 2 hours. Outcomes were compared using univariate and multivariable analyses. Adjusted odds ratios (aOR) were estimated using a logistic regression multivariable model that included potential cofounders.

RESULTS

During the study period, 614 women were included, 305 in maternity unit A and 309 in maternity unit B. Women's pre-existing characteristics were comparable between the two maternity units. Women delivering in the maternity unit A had significantly lower risks of having an operative delivery compared to women delivering in the maternity unit B (respectively 18.4 vs 26.9%; aOR = 0.64; 95%CI [0.43 - 0.96]). Perinatal outcomes were comparable in the two maternity units, particularly in terms of post-partum hemorrhage rates (7.4 vs 7.8%; aOR = 1,19 [0.65 - 2.19]).

CONCLUSION

Increasing the possible length of the delayed pushing period from 2 to 3 hours after the diagnosis of full cervical dilation in low-risk nulliparous women appears to reduce operative deliveries without adverse effects on maternal or neonatal morbidity.

Benefits of the «en caul» technique for extremely preterm breech vaginal delivery

INTRODUCTION

The "en caul" technique, i.e. delivery with intact membranes, may reduce the risk of obstetric trauma in vaginal breech delivery of extreme preterm infants. We aimed at comparing perinatal mortality and morbidity among extremely preterm breech vaginal deliveries between infants delivered "en caul" and those with "ruptured membranes".

MATERIAL AND METHODS

We performed a fourteen-year retrospective study in a tertiary university center. All vaginal deliveries of singleton breech live infants with an antenatal decision of active resuscitation between 24 weeks and 27⁺⁶ weeks were included. Perinatal outcomes were compared between the "en caul" group, with intact membranes at the onset of pushing efforts and the "ruptured membranes" group, with ruptured membranes at the onset of pushing efforts. The primary outcome was perinatal mortality defined by intrapartum or neonatal death. The secondary outcomes were fetal extraction difficulties, arterial pH and 5 min Apgar score.

RESULTS

We included 52 infants in the "en caul" group and 71 in the "ruptured membranes" group. The perinatal mortality rate did not differ between the two groups (19.2% in the "en caul" group versus 28.2% in the "ruptured membranes" group, p = 0.25). The mean arterial pH at birth was higher in the « en caul » group (7.32 ± 0.1 vs 7.24 ± 0.1, p = 0.001). There were no differences between the groups for fetal extraction difficulties, especially fetal head entrapment (9.6% versus 9.9%).

CONCLUSION

Even though the "en caul" technique does not seem to decrease the perinatal mortality rate, it remains a simple technique, which could improve neonatal morbidity.

TRANSCOV, a multidisciplinary project to evaluate long distance COVID patients transfers

Background

Faced with an abrupt surge of severe COVID patients in March and April 2020, intensive care units (ICU) from four French regions transferred around 660 patients towards six other regions and four neighbouring countries. The intensity and the diversity of the vectors used (plane, helicopter, train, ambulance), during this wave of medical evacuations make it an unprecedented event. The aim of TRANSCOV is to examine the impact of long distance transfers on patient's health and to understand how actors collaborated to overcome clinical and logistical challenges.

Methods

TRANSCOV is made of three disciplinary components: 1) interviews with clinicians and health authorities staff involved in the organisation and realisation of the transfers as part of the qualitative component; 2) a retrospective cohort collecting clinical parameters and pathway details before during and after transfer; 3) a collection of data regarding human and logistical resources mobilised during transfers as part of an economical evaluation.

Results

Preliminary results indicate that prior experience in medical evacuations proved useful to collaborate effectively in the exceptional circumstances prevailing in spring 2020. Clinicians had to establish quickly eligibility criteria for transfer. Actors' opinions may vary on the appropriateness of vectors to transfer isolated (e.g. via helicopter) or grouped (train) patients. Early epidemiological data suggest that transferred patients were younger and experienced comparable, if not lower, in-hospital mortality compared to other patients. The economic evaluation is in progress.

Conclusions

Initial results indicate that effective collaborations led to the selection of clinically eligible patients and the realisation of safe distant transfers.

Key messages

Healthcare organisations have been able to adapt and create organizational innovations to respond to COVID-19. Multidisciplinary approaches are appropriate to evaluate such complex innovations.

[Term Prelabor Rupture of Membranes: CNGOF Guidelines for Clinical Practice - Short Text]

OBJECTIVE

To determine the management of patients with term prelabor rupture of membranes.

METHODS

Synthesis of the literature from the PubMed and Cochrane databases and the recommendations of French and foreign societies and colleges.

RESULTS

Term prelabor rupture of membranes is considered a physiological process up to 12hours of rupture (Professional consensus). In case of expectant management and with a low rate of antibiotic prophylaxis, home care compared to hospitalization could be associated with an increase in neonatal infections (LE3), especially in case of group B streptococcus colonization (LE3). Home care is therefore not recommended (Grade C). In the absence of spontaneous labor within 12hours of rupture, antibiotic prophylaxis could reduce the risk of maternal intrauterine infection but not of neonatal infection (LE3). Its use after 12hours of rupture in term prelabor rupture of the membranes is therefore recommended (Grade C). When antibiotic prophylaxis is indicated, intravenous beta-lactams are recommended (Grade C). Induction of labor with oxytocin (LE1), prostaglandin E2 (LE1) or misoprostol (LE1), is associated with shorter rupture of membranes to delivery intervals when compared to expectant management. Compared with expectant management, immediate induction of labor is not associated with lower rates of neonatal infection (LE1), even among women with a positive streptococcus B vaginal swab (LE2). Thus, expectant management can be offered without increasing the risk of neonatal infection (Grade B). Induction of labor is not associated with an increase or decrease in the cesarean delivery rate (LE2), whatever parity (LE2) or Bishop score at admission (LE3). Induction can thus be proposed without increasing the risk of cesarean delivery (Grade B). No induction method (oxytocin, dinoprostone, misoprostol or Foley® catheter) has demonstrated superiority over another, whether to reduce rate of intrauterine or neonatal infection, rate of cesarean delivery or to shorten rupture of membranes to delivery intervals regardless of Bishop's score and parity.

CONCLUSION

Term prelabor rupture of membranes is a frequent event. A 12-hour delay without onset of spontaneous labor was chosen to differentiate a physiological condition from a potentially unsafe situation justifying an antibiotic prophylaxis. Expectant management or induction of labor can both be proposed, even in case of positive screening for streptococcus B, depending on the patient's wishes and maternity units' organization (Professional consensus).

[Term Prelabor Rupture of Membranes: CNGOF Guidelines for Clinical Practice - Methods for Inducing Labor]

OBJECTIVES

To assess the studies comparing induction methods in women with term prelabor rupture of the membranes and establish if one is superior to the others.

METHODS

The MedLine database, the Cochrane Library and the recommendations from the French and foreign obstetrical societies or colleges have been consulted.

RESULTS

The included studies compared medical induction methods: oxytocin (intravenous), dinoprostone (vaginal gel, pessary or intracervical gel), and misoprostol (oral or vaginal route); and a mechanical induction method: the Foley catheter. The primary outcome measures were: labor induction to delivery interval, number of women delivered within 12 or 24hours of initiation of induction and cesarean delivery rate. The small sample size of the included studies as well as the limited number of reported complications does not provide a reasonable basis for concluding on the secondary outcome measures: pyrexia, chorioamnionitis, uterine tachysystole, Apgar scores of<7 at 5minutes. Induction of labor with misoprostol (oral and vaginal) reduced the labor induction to delivery interval compared with dinoprostone (LE2). This interval was unchanged when comparing induction with oxytocin and Foley catheter (LE2). The data comparing this interval in women induced with dinoprostone versus oxytocin and misoprostol versus oxytocin is limited or inconsistent. The cesarean delivery rate was comparable in women induced with dinoprostone (vaginal gel) versus oxytocin (LE2), misoprostol (oral and vaginal route) versus oxytocin (LE2), Foley catheter versus oxytocin (LE2), misoprostol versus dinoprostone (LE2) and misoprostol versus Foley catheter (LE2). The number of women delivered within 24hours of initiation of induction was comparable when induced with oral misoprostol versus oxytocin (LE2) and Foley catheter versus oxytocin (LE2). There is a lack of data for this outcome when comparing dinoprostone versus oxytocin, vaginal misoprotsol versus oxytocin, and misoprostol (oral and vaginal) versus dinoprostone. No induction method is superior to another for nulliparous women or women with unfavorable cervix (LE2).

CONCLUSION

The superiority of an induction method, in terms of effectiveness or safety, could not be established with the current available data for women with term prelabor rupture of the membranes. An increased risk of chorioamnionitis due to induction using Foley catheter could not be ruled out by the available data. All medical methods are suitable for inducing women with term prelabor rupture of the membranes (Grade B).

Women and academic careers in obstetrics and gynaecology: aspirations and obstacles among postgraduate trainees - a mixed-methods study

OBJECTIVE

To examine the relationship between gender and a career in academic medicine.

DESIGN

Mixed-methods study.

SETTING

Obstetrics-gynaecology postgraduate training programme in Paris, France.

SAMPLE

Postgraduate trainees in obstetrics-gynaecology (n = 204).

METHODS

Statistical analysis of quantitative survey data, thematic analysis of qualitative interview data and integrative analysis.

MAIN OUTCOME MEASURES

Women's aspirations and obstacles related to their decision about a career in academic medicine.

RESULTS

A career in academic medicine was envisaged by 13% of the women residents and 27% of the men (P = 0.01). Women reported receiving advice from a mentor less often than men (38.8% versus 52.9%, P = 0.002). Overall, 40.6% of women and 2.9% of men reported experiencing gender discrimination (P < 0.001). In response to the question 'Do you have doubts about your ability to pursue or succeed at an academic career?', 62.4% of the women and only 17.7% of the men answered yes (P < 0.001). The global analysis identified the following obstacles: persistent gender stereotypes that produce everyday sexism, lack of identification with male role models, lack of mentors, perceived discrimination, an ideal of professional excellence that is difficult to attain, constraining professional organisational norms, inequality between men and women in the domestic and family spheres, and finally self-censorship and important doubts about their ability to combine a demanding career and a fulfilling personal life.

CONCLUSIONS

Women reported the desire to follow a career in academic medicine half as often as men. Improving the presence and visibility of role models for residents and combating workplace discrimination will address some of the barriers to women choosing a career in academic medicine.

TWEETABLE ABSTRACT

Women obstetric trainees in France are only half as likely as men to envisage following an academic path.

Effects of Keto-analogues on Phosphocalcic and Aminoacid Metabolism in Dialysed Patients: A Crossover Study

It has been suggested that calcium salts of keto-analogues (KA) have beneficial effects on phosphocalcic and aminoacid (AA) metabolism. To confirm this, their short-term effects were evaluated on chronic dialyzed patients. In a prospective, randomised, crossover study, eight and seven patients were put on KA (200 mg/kg/d) and assigned either a low-protein diet (LP:0.4 g/kg/d) or a normal one (NP: 1 g/kg/d) for 15 days. The two treatments were interchanged after 15 days of washout. KA.LP was accompanied by: a) decreases in calorie intake (12%; p = 0.001) and in blood concentrations of albumin (5%, p = 0.004), urea (32 %, p = 0.001), phosphate (29%, p = 0.001), parathormone (27%, p = 0.008), isoleucine (24%, p = 0.04), 1 and 3 methyl-histidine (71%, p = 0.03,; 24%, p = 0.005), valine (19%, p = 0.004) and hydroxyproline (85%, p = 0.009); b) increases in calcemia (9%, p = 0.002), cystathionine (991%, p = 0.0001) and threonine (22%, p = 0.04).

KA.NP was accompanied by: a) decreases in phosphatemia (15%, p = 0.03) and parathormone (18 %, p = 0.06); b) increases in calcemia (9%, p = 0.002), cystathionine (427 %, p = 0.0001), and phenylalanine (28%, p = 0.013).

Calcium salts of keto-analogues together with a low or normal protein diet thus seem to reduce blood concentrations of phosphates and parathormone, and raise calcium; however their action on aminoacids needs further investigation.

The SigmaR1 chaperone drives breast and colorectal cancer cell migration by tuning SK3-dependent Ca2+ homeostasis

The remodeling of calcium homeostasis contributes to the cancer hallmarks and the molecular mechanisms involved in calcium channel regulation in tumors remain to be characterized. Here, we report that SigmaR1, a stress-activated chaperone, is required to increase calcium influx by triggering the coupling between SK3, a Ca2+-activated K+ channel (KCNN3) and the voltage-independent calcium channel Orai1. We show that SigmaR1 physically binds SK3 in BC cells. Inhibition of SigmaR1 activity, either by molecular silencing or by the use of sigma ligand (igmesine), decreased SK3 current and Ca2+ entry in breast cancer (BC) and colorectal cancer (CRC) cells. Interestingly, SigmaR1 inhibition diminished SK3 and/or Orai1 levels in lipid nanodomains isolated from BC cells. Analyses of tissue microarray from CRC patients showed higher SigmaR1 expression levels in cancer samples and a correlation with tumor grade. Moreover, the exploration of a cohort of 4937 BC patients indicated that high expression of SigmaR1 and Orai1 channels was significantly correlated to a lower overall survival. As the SK3/Orai1 tandem drives invasive process in CRC and bone metastasis progression in BC, our results may inaugurate innovative therapeutic approaches targeting SigmaR1 to control the remodeling of Ca2+ homeostasis in epithelial cancers.

Ophiobolin A induces paraptosis-like cell death in human glioblastoma cells by decreasing BKCa channel activity

Glioblastoma multiforme (GBM) is the most lethal and common malignant human brain tumor. The intrinsic resistance of highly invasive GBM cells to radiation- and chemotherapy-induced apoptosis accounts for the generally dismal treatment outcomes. This study investigated ophiobolin A (OP-A), a fungal metabolite from Bipolaris species, for its promising anticancer activity against human GBM cells exhibiting varying degrees of resistance to proapoptotic stimuli. We found that OP-A induced marked changes in the dynamic organization of the F-actin cytoskeleton, and inhibited the proliferation and migration of GBM cells, likely by inhibiting big conductance Ca(2+)-activated K(+) channel (BKCa) channel activity. Moreover, our results indicated that OP-A induced paraptosis-like cell death in GBM cells, which correlated with the vacuolization, possibly brought about by the swelling and fusion of mitochondria and/or the endoplasmic reticulum (ER). In addition, the OP-A-induced cell death did not involve the activation of caspases. We also showed that the expression of BKCa channels colocalized with these two organelles (mitochondria and ER) was affected in this programmed cell death pathway. Thus, this study reveals a novel mechanism of action associated with the anticancer effects of OP-A, which involves the induction of paraptosis through the disruption of internal potassium ion homeostasis. Our findings offer a promising therapeutic strategy to overcome the intrinsic resistance of GBM cells to proapoptotic stimuli.

New alkyl-lipid blockers of SK3 channels reduce cancer cell migration and occurrence of metastasis

Edelfosine is an inhibitor of SK3 channel mediated cell migration. However, this compound bears adverse in vivo side effects. Using cell SK3 dependent cell-migration assay, patch-clamp, (125)I-apamin binding, and in vivo experiments we tested the ability of 15 lipid derivatives with chemical structures inspired from edelfosine to inhibit SK3 channels. Using a structure-activity relationship approach we identified an edelfosine analog named Ohmline (1-O-hexadecyl- 2-O-methyl-sn-glycero-3-lactose) with potent inhibitory effects on the SK3 channel. Its potency was greater for SK3 channels than for SK1 channels; it did not affect IKCa channels and only slightly but not significantly affected SK2 channels. This is the first SKCa channel blocker that can be used to discriminate between SK2 and SK1/SK3 channels and represents a useful tool to investigate the functional role of SK3 channels in peripheral tissues (that do not express SK1 channels). This compound, which acts with an IC(50) of 300 nM, did not displace apamin from SKCa channels and had no effect on non-specific edelfosine targets such as protein kinase C (PKC), receptors for platelet activating factor (PAF) and lysophosphatidic acid (LPA), as well as non-cancerous cells. This is promising because the pitfalls associated with the use of edelfosine-like compounds have been that their effective and high concentrations are often cytotoxic due to their detergent-like character causing normal cell lysis. Finally, Ohmline reduced metastasis development in a mice model of tumor indicating that this compound could become a lead compound for the first class of lipid-antimetastatic agent.

Targeting SKCa channels in cancer: potential new therapeutic approaches

Many studies have reported changes in potassium channel expression in many cancers and the involvement of these channels in various stages of cancer progression. By contrast, data concerning SKCa channels (small conductance calcium-activated potassium channels) have only recently become available. This review aims i) to present the structure and physiology of SKCa channels, ii) to provide an overview of published data concerning the SKCa proteins produced in tumor cells, and, whenever possible, the biological function assigned to them and iii) to review previous and novel modulators of SKCa channels. SKCa channels are activated by low concentrations of intracellular calcium and consist of homo- or heteromeric assemblies of α-subunits named SK1, SK2 and SK3. SK2-3 channels are expressed in tumors and have been assigned a biological function in cancer cells: the enhancement of cell proliferation and cell migration by hijacking the functions of SK2 and SK3 channels, respectively. Two major classes of SKCa modulators have been described: toxins (apamin) and small synthetic molecules. Most SKCa blockers are pore blockers, but some modify the calcium sensitivity of SKCa channels without interacting with the apamin binding site. In this review, we present edelfosine and ohmline as atypical anticancer agents and novel SK3 inhibitors. Edelfosine and ohmline are synthetic alkyl-lipids with structures different from all previously described SKCa modulators. They should pave the way for the development of a new class of migration-targeted anticancer agents. We believe that such blockers have potential for use in the prevention or treatment of metastasis.

The SK3/K(Ca)2.3 potassium channel is a new cellular target for edelfosine

BACKGROUND AND PURPOSE

The 1-O-octadecyl-2-O-methyl-sn-glycero-3-phosphocholine (edelfosine) is an ether-linked phospholipid with promising anti-cancer properties but some side effects that preclude its full clinical therapeutic exploitation. We hypothesized that this lipid could interact with plasma membrane ion channels and modulate their function.

EXPERIMENTAL APPROACH

Using cell migration-proliferation assays, patch clamp, spectrofluorimetry and ¹²⁵I-Apamin binding experiments, we studied the effects of edelfosine on the migration of breast cancer MDA-MB-435s cells, mediated by the small conductance Ca²(+) -activated K(+) channel, SK3/K(Ca)2.3.

KEY RESULTS

Edelfosine (1 µM) caused plasma membrane depolarization by substantially inhibiting activity of SK3/K(Ca)2.3 channels, which we had previously demonstrated to play an important role in cancer cell migration. Edelfosine did not inhibit ¹²⁵I-Apamin binding to this SK(Ca) channel; rather, it reduced the calcium sensitivity of SK3/K(Ca)2.3 channel and dramatically decreased intracellular Ca²(+) concentration, probably by insertion in the plasma membrane, as suggested by proteinase K experiments. Edelfosine reduced cell migration to the same extent as known SK(Ca) channel blockers. In contrast, K+ channel openers prevented edelfosine-induced anti-migratory effects. SK3 protein knockdown decreased cell migration and totally abolished the effect of edelfosine on MDA-MB-435s cell migration. In contrast, transient expression of SK3/K(Ca)2.3 protein in a SK3/K(Ca)2.3-deficient cell line increased cell migration and made these cells responsive to edelfosine.

CONCLUSIONS AND IMPLICATIONS

Our data clearly establish edelfosine as an inhibitor of cancer cell migration by acting on SK3/K(Ca)2.3 channels and provide insights into the future development of a new class of migration-targeted, anti-cancer agents.

[Diversity of hepatitis B virus and its consequences]

The genetic diversity of hepatitis B virus (HBV) was defined on the basis of the characterisation of the major determinants in the antigenic loop of HBs antigen (Ag). Historically, nine subtypes were defined. Recently, based on sequence analysis, HBV genomes have been classified into eight genotypes (A-H) which present distinct geographical distributions. Genetic mutants may have a selective advantage in patients treated with passive or active immunization (hepatitis B immune globulin or vaccine). Anti-viral treatment can be responsible for the emergence of escape mutants with resistant mutations in the polymerase gene. These substitutions can lead to changes on HBsAg structure. The lack of detection of several envelope mutant viruses by some commercial HBsAg assays has been demonstrated. Substitutions involving precore/core region have also been found to prevent HBeAg synthesis.

Surveillance épidémiologique des donneurs de sang homologues et risque résiduel en France entre 2001 et 2003

The national surveillance of French blood donors is performed by the Institut de Veille Sanitaire and the National Reference Center for Hepatitis B and C in transfusion in collaboration with the Etablissement Français du Sang and the Army blood center. The main objectives of this surveillance are to evaluate trends in prevalence and incidence rates of blood-borne infections in the blood donor population, to identify routes of contamination and to assess residual risk. This exhaustive surveillance also contributes to evaluate the blood donor selection and the impact of measures taken to prevent infections in the general population. The analyse of the database of all blood donations obtained from 2001 to 2003 has shown that prevalence rates were stable in the study period (0.60 per 10(4) donors for HIV, 8.0 per 10(4) donors for HCV, 1.8 per 10(4) first-time donors for HBs Ag and 0.56 per 10(4) donors for HTLV), The incidence rate of HIV and HBV (1 per 10(5) person-years) was three-times higher than for HCV (0.35 per 10(5) person-years) and eleven times higher than for HTLV (0.09 per 10(5) person-years). At least, the residual risk of transfusion-transmitted viral infections is very low: 1/3,150,000 donations for HIV, 1/10,000,000 donations for HCV and 1/640,000 donations for HBV. The yield of Nucleic Acid Testing (NAT) is limited since only 2 donations for HIV and 3 for HCV which were negative for antibodies were discarded thank to the NAT.

Determination of hepatitis B virus subtypes by an enzyme immunoassay method using monoclonal antibodies to type-specific epitopes of HBsAg

We described a Hepatitis B surface antigen (HBsAg) subtyping method based on a commercial enzyme immunoassay (EIA) for detection of HBsAg in which the procedure was modified to include the use of monoclonal antibodies with restricted anti-HBs specificities. This method, which was able to classify HBsAg as: ayw1, ayw2, ayw3, ayw3* (intermediate between ayw3 and ayw4), ayw4, ayr, adw2, adw4 and adr, was compared to counter electrophoresis procedure (CEP) by testing HBsAg positive sera from blood donors included in a prospective national epidemiological survey. Among the 256 HBsAg positive samples tested with both techniques, 111 (43.3%) could not be subtyped with CEP vs 10 (3.9%) with our modified EIA. This difference was related to the serum HBsAg concentration which must be greater than 3000 ng/mL and 100 ng/mL for CEP and EIA, respectively. The results obtained from 145 sera with both methods were concordant. Seventeen out of 18 samples partially classified as ay with CEP were completely determined with EIA. This reliable procedure, derived from commercially available reagents, can be easily used in several applications such as large epidemiologic studies and as a substitute for nucleotide sequencing genotyping which is not adapted for large-scale screening and not applicable on samples from nonviremic hepatitis B virus (HBV) carriers.

Microalbuminuria and markers of the atherosclerotic process: the D.E. S.I.R. study

The relationship between microalbuminuria and tissue-type plasminogen activator antigen (tPA-ag) and fibrinogen was evaluated in non-diabetic subjects. Subjects were participants of the D.E.S.I. R. (Data from an Epidemiological Study on the Insulin Resistance syndrome) Study. Analyses were carried out on 2248 women and 2402 men for fibrinogen and on 272 women and 284 men for tPA-ag. Microalbuminuria was defined as urinary albumin concentration greater than 20 mg/l. Men with microalbuminuria had a 6% higher fibrinogen concentration than those without (3.07 g/l (95% confidence interval: 2.99,3.15) vs. 2.89 g/l (2.87,2.91), adjusted for age and smoking). This relationship existed in hypertensive as well as non-hypertensive subjects. The association between microalbuminuria and tPA-ag existed only in hypertensive men, those with microalbuminuria having a 21% higher tPA-ag than those without (4.39 ng/ml (3.70,5.08) vs. 3.63 ng/ml (3.32,3.94), adjusted for age and smoking). Adjustment for other risk markers for cardiovascular disease did not change the results. There was no relationship between microalbuminuria and these haemostatic factors in women. The results of this study suggest that in non-diabetic men, microalbuminuria is associated with fibrinogen, but with tPA-ag only when concomitant with hypertension.

GB virus type C/HGV markers in HCV RNA-positive French blood donors: correlation with HCV genotypes and risk factors

BACKGROUND

Exposure to GB virus type C/HGV (GBV-C/HGV) could be determined by detection either of RNA by RT-PCR or of antibodies of the envelope protein E2.

STUDY DESIGN AND METHODS

The aim of the study was to determine the proportion of the GBV-C/HGV markers of infection in a blood donor population infected with HCV and to identify GBV-C/HGV routes of transmission that are associated with HCV genotypes and risk factors.

RESULTS

Among 306 HCV RNA-positive blood donors, the proportion of GBV-C/HGV RNA-positive donors and anti-E2-positive donors was 19.3 percent (95% CI = 15.0-24.2%) and 42.1 percent (95% CI = 36.6-47.9%), respectively. Exposure to GBV-C/HGV (RNA or anti-E2) was significantly associated with the risk factor of IV drug use. There was a trend toward association with HCV subtypes 1a and 3a, probably because these HCV subtypes are the most frequent in IV drug users. No correlation was observed between ALT elevation and the presence of GBV-C/HGV RNA.

CONCLUSION

In persons with HCV infection, IV drug use seems to be a major route of GBV-C/HGV transmission. Precautions taken to avoid HCV infection will probably also decrease GBV-C/HGV transmission.

Prevalence of present and past hepatitis G virus infection in a French haemodialysis centre

BACKGROUND

Previous studies, detecting GB virus-C (GBV-C) or hepatitis G virus (HGV) RNA by using reverse transcriptase polymerase chain reaction (RT-PCR), have shown that haemodialysis (HD) patients had a high risk of being infected and viraemic with this virus. A past GBV-C/HGV contact can now be detected by testing for antibodies directed against the GBV-C/HGV envelope protein E2 (anti-E2).

METHODS

In order to evaluate GBV-C/HGV contact, 120 patients undergoing chronic HD were tested for GBV-C/HGV RNA by RT-PCR and anti-E2 antibodies by ELISA. GBV-C/HGV viraemic patients were followed prospectively for 18 months, and retrospectively when sera were stored. The total follow-up was between 18 and 78 months.

RESULTS

GBV-C/HGV RNA was detected in 17 patients (14%), and 18 patients (15%) had a significant level of anti-E2 antibodies. No positive anti-E2 specimens were also positive for GBV-C/HGV RNA and vice versa. A total of 35 patients (29%) were contaminated with GBV-C/HGV. Sixteen of the 17 viraemic patients had a persistent viraemia (follow-up 18-78 months) and one cleared the virus during the study period. A past or present GBV-C/HGV contact was statistically correlated with the duration of HD and hepatitis C virus (HCV) infection, but was independent of age, hepatitis B virus (HBV) infection, and alanine aminotransferase (ALT) level.

CONCLUSIONS

Twenty-nine per cent of patients who underwent HD in our centre have been infected by GBV-C/HGV, 49% were still viraemic and 51% have developed anti-E2 antibodies, indicating a past contact with GBV-C/HGV. Our results demonstrate that the prevalence of GBV-C/HGV contact in HD was underestimated when only RT-PCR was used. Therefore GBV-C/HGV contact is probably much more frequent in HD than previous studies would suggest and is at this time not correlated with hepatotoxicity. Anti-HCV antibodies blood screening since 1990 and recent changes in managing HD patients have probably reduced GBV-C/HGV contact in the same way.

Effects of simvastatin, pentoxifylline and spironolactone on hepatic fibrosis and portal hypertension in rats with bile duct ligation

AIMS/METHODS

Our aim was to study the antifibrotic and hemodynamic effects of simvastatin (SMV), pentoxifylline (PTX) and spironolactone (SPN), three drugs which may have antifibrotic and/or portal hypotensive properties, in a model of hepatic fibrosis and portal hypertension induced in rats by bile duct ligation. A blind study was performed in five groups of 53 Sprague-Dawley rats: sham, placebo (PL), SMV (2.5 mg x kg(-1) x J(-1)), PTX (50 mg x kg(-1) x J(-1)) and SPN (100 mg x kg(-1) x J(-1)). Drugs were administered by daily gavage over a 4-week period as soon as bile duct ligation was performed. At day 28, the following parameters were evaluated: area of hepatic fibrosis by image analysis after staining collagen with picrosirius and plasma concentrations of hyaluronate, splanchnic and systemic hemodynamics (radiolabeled microspheres).

RESULTS

Portal venous pressure (PL: 15.5+/-1.5, SMV: 15.8+/-2.5, PTX: 15.9+/-1.8, SPN: 13.5+/-2.1 mmHg, p<0.05) and porto-systemic shunts (PL: 30+/-31, SMV: 18+/-27, PTX: 25+/-24, SPN: 5+/-4%, p<0.05) were significantly reduced in the SPN group; other hemodynamic parameters were not significantly altered. There was a significant correlation between portosystemic shunts and portal pressure (r(s)=0.47, p<0.01). The area of fibrosis was not significantly different among the four groups of bile duct ligated rats (PL: 8.7+/-3.9, SMV: 7.1+/-3.6, PTX: 7.8+/-2.7, SPN: 6.6+/-3.3%) but was higher than in sham rats (1.5+/-0.5%, p<0.001). Hyaluronate was significantly higher in bile duct ligated rats (from 374+/-162 to 420+/-131 microg/l, among the four groups) than in sham rats (52+/-16 microg/l, p<0.0001).

CONCLUSIONS

In this model, none of the drugs prevented hepatic fibrosis. On the other hand, spironolactone decreased portal pressure and prevented porto-systemic shunts. Therefore, this drug may have beneficial effects in patients with early portal hypertension.

1,25-Dihydroxyvitamin D3 regulates gamma 1 transpeptidase activity in rat brain

gamma-Glutamyl transpeptidase (gamma-GT), primarily described as a kidney enzyme, is also expressed in several cell types of the central nervous system (CNS). It is involved in the glutathione cycle and in cysteine transport. Here we report that the specific activity of this enzyme is transiently increased in the rat brain, following a treatment with 1,25-dihydroxyvitamin D3 (1,25-D3), the active form of vitamin D. In vitro experiments showed that this positive regulatory effect does not affect endothelial cells of the brain microvessels, but does affect pericytes and parenchymal astrocytes. Changes in the specific activity of gamma-GT were not correlated with any important modification of brain amino acid concentrations. Since gamma-GT is though to participate in the scavenging of reactive oxygen species, these data suggest that 1,25-D3 could be an effector controlling detoxification processes in the brain.

[Prevalence of microalbuminuria in French type 2 diabetics followed by their general practitioner]

Microalbuminuria is a risk marker for cardiovascular morbidity and mortality in Type 2 diabetes. We studied microalbuminuria among French Type 2 diabetic patients in general practice, because we set-up a trial using cardiovascular events as end-points. Two thousand twenty four volunteer patients were studied for Urinary Albumin Concentration (UAC) during outpatient visit to general practitioners. The UAC was measured on first samples. If UAC was positive (> or = 20 mg/l), a second sample was requested. If UAC was positive two times, persistently elevated UAC was identified (micro or macroalbuminuria). Clinical characteristic, cardiovascular antecedents and risk factors were studied. One hundred five first samples were excluded due to urinary infection; 1,217 others displayed normal UAC (< 20 mg/l); 63.4%; group N), 557 microalbuminuria (20-200 mg/l; 29.0%, group mu), and 145 others macroalbuminuria (> 200 mg/l; 7.6%; group M). Among subjects with positive first sample, 26.5% had persistent albuminuria. There was no intergroup difference for age, but males were more frequent in groups mu or M than N (p < 10(-4)). Blood pressure and body mass index varied between groups. Smokers and alcoholic subjects were more frequent in groups mu and M than N (p = 0.037 and p = 0.0003 respectively), as were cases with myocardial infarction (p = 0.0026), lower limb arteritis (p < 10(-4)), and laser-treated diabetic retinopathy (p = 0.0002). Antihypertensive treatments were taken by 61% of the subjects. Elevated UAC (micro or macroalbuminuria) is frequent among french Type 2 diabetic patients cared by their general practitioners, and is associated with a high cardiovascular risk profile.(ABSTRACT TRUNCATED AT 250 WORDS)

Anti-hepatitis C virus (anti-HCV) seroconversion in patients undergoing hemodialysis: comparison of second- and third-generation anti-HCV assays

BACKGROUND

The results obtained in sequential specimens from recently infected subjects generally provide the best means of comparing the sensitivity of assays.

STUDY DESIGN AND METHODS

The sensitivity of second- and third-generation assays for antibody to hepatitis C virus (HCV) was compared on sequential specimens, generally collected at monthly intervals from 45 patients undergoing hemodialysis who seroconverted for HCV between 1980 and 1990.

RESULTS

Fifteen patients (33%) were positive earlier in the third-generation enzyme-linked immunosorbent assay (ELISA), with a mean difference of 17 days (range, 7-30) between the last negative and the first positive specimens. At the first rise in alanine aminotransferase, and at its peak, 63 and 91 percent of the patients, respectively, were anti-HCV positive in the third-generation ELISA. Third-generation recombinant immunoblot assay (RIBA) reacted at the same time as third-generation ELISA. Of the first specimens that were positive in second-generation ELISA, 44 percent reacted and 56 percent were indeterminate in third-generation RIBA, while 10 percent reacted, 72 percent were indeterminate, and 18 percent did not react in second-generation RIBA. From the beginning to the end of the follow-up, antibody to c33c was the most prevalent, followed in descending order by antibody to c22-3, antibody to c100-3, and antibody to NS5: 56, 54, 26, and 18 percent, respectively, at time 0, and 100, 86, 83, and 31 percent, respectively, 12 months later.

CONCLUSION

Third-generation assays (both ELISA and RIBA) were more sensitive than second-generation assays in the diagnosis of HCV infection, in that positive results were obtained earlier and a higher proportion of specimens were confirmed positive in RIBA testing.

Day time and night time effects of 24R,25-dihydroxycholecalciferol on renal alkaline phosphatase and gamma-glutamyltransferase activities in intact rats

The effects of 24R,25-dihydroxycholecalciferol [24,25(OH)2 CC] on alkaline phosphatase (APA), gamma-glutamyltransferase (gamma-GT) and acid phosphatase (AP) activities were investigated on renal cortex slices of intact rats killed at 18h00 or at 06h00. At 06h00, three, six and nine hours after a single intraperitoneal injection of 24,25(OH)2 CC, APA activity was increased by 30%, 51% and 29%, respectively and gamma-GT activity, by 25%, 39% and 38%, as compared to their controls. AP on the other hand was not modified at all. These enzymatic stimulations were statistically higher than those measured at 18h00, respectively APA: 11%, 25%, 28% and gamma-GT: 2%, 20%, 22%. They can be explained by variations in new protein synthesis in relation with rat activity periods. Physiological significance of these renal effects remains to be elaborated.

[In vivo effects of 24R,25-dihydroxyvitamin D3 on kidney alkaline phosphatase and gamma-glutamyltransferase of hypophysectomized rats]

The effects of 24R, 25-dihydroxyvitamin D3 (24, 25 (OH)2 D3) on alkaline phosphatase (ALP), gamma-glutamyltransferase (GGT) and acid phosphatase (ACP) activities were investigated on renal cortex of hypophysectomized (Hx) rats. ALP activity was increased by +27, +56 and +60% as compared to controls respectively 3, 6 and 12 h after intraperitoneal administration of the secosteroid (10 pmoles/100 g body weight). Stimulations of GGT activity began only after 6 h (+30%) and 12 h (+ 46%). ACP activity was not modified. In vivo, the two enzymatic inductions in kidneys of Hx rats were higher and longer than those obtained in vitro.

[Correlation between hepatitis C virus (HVC) RNA and anti-HVC antibodies in a hemodialysis population]

Polymerase chain reaction (PCR) was applied to detect HCV-RNA in 75 hemodialyzed patients. Anti-HCV status was determined by ELISA-2 and by RIBA-2 for reactive samples by ELISA. ALT levels were monthly determined during the year preceding the end of the study. For 60 patients, anti-HCV serology was known since 1989 and 39 of them were tested for the presence of HCV-RNA at least four times during the 2 preceding years. The 9 patients who were negative for anti-HCV antibodies were negative by PCR. Of the 7 patients with an indeterminate profile by RIBA-2, 3 were positive by PCR: 1/1 with C-33c band only and 2/6 with C22-3 band only. Of the 59 patients reactive by RlBA-2, 57 were HCV-RNA positive. Of the 2 HCV-RNA negative patients, one had been PCR positive before interferon therapy. Of the 38 patients without acute hepatitis tested by PCR on 5 successive samples, all the specimens of 11 and 23 patients were HCV-RNA negative and HCV-RNA positive respectively. In 4 patients, a transient viremia was observed. The group of HCV-RNA positive patients had mean ALT levels greater than those who were negative. A correlation was established between HCV infection and both the time on dialysis and the number of blood transfusions. A high concordance (97%) was observed between antibodies to HCV and HCV-RNA.

Antibodies to hepatitis C virus by second generation test in hemodialyzed patients

To assess the prevalence and the incidence of hepatitis C virus (HCV) in a dialysis unit, we prospectively tested for anti-HCV in chronic hemodialysis patients and staff members since January 1989, using a first generation assay. Incidence was nil in staff and low in patients (3.7% in 89, 1% in 90), and prevalence was 30% in patients. In January 1991 blood samples from 115 patients were tested by first (EL1) and second generation (EL2) ELISA (Ortho Diagnostic System). Positive subjects were tested by a RIBA-2 confirmation test. Fifty-three patients were negative by all tests. Positive tests were observed in 62 patients (54%) including 36 positive in EL1 and EL2, and 26 only by EL2. All positive patients were reactive by RIBA-2 but nine were classified undetermined (only one positive band). In five patients reactivity of antibodies to 5-1-1 and C-100-3 gradually declined during the study. Second generation tests gave a better correlation with time on dialysis and blood transfusion. We conclude that second generation tests for HCV are more accurate for estimating true prevalence of HCV infection in hemodialysis units.

Detection of hepatitis C virus by polym erase chain reaction in haemodialysed patients in relationship to anti-HCV status

HCV RNA was determined by the polymerase chain reaction (PCR) in 41 haemodialysed patients with a known anti-HCV status (ELISA and RIBA-2) and a monthly alanine aminotransferase (ALT) level determination. No histological examination of the liver tissue was available. Four samples from each patient were collected at 6 month intervals for 18 months. Seven patients negative for anti-HCV during the entire follow-up gave negative PCR results on the four samples. Two patients who were anti-HCV-negative upon entry into the study seroconverted to HCV during follow-up. HCV RNA was detected during the acute phase of hepatitis. HCV RNA was no longer detectable after antiviral therapy was administered to one patient. Out of 27 anti-HCV-positive patients, 24 had persistent viraemia, 2 had transient viraemia (1 sample PCR-negative and 3 samples PCR-positive) and 1 was PCR-negative on the 4 samples. Thirteen of the 26 viraemic patients had a normal ALT level during the preceding 3 years. Three patients with a C22-3 band alone by RIBA-2 were negative by PCR, whereas two patients with a C33-c band alone were PCR-positive on the four samples. These results suggest that HCV viraemia was strongly associated with anti-HCV in haemodialysed patients with or without biological hepatitis.

[Microalbuminuria and left ventricular hypertrophy in essential arterial hypertension. A study in non-diabetic patients]

To evaluate the relationship between urinary albumin excretion and left ventricular hypertrophy in essential hypertension, we studied, cross-sectionally, 64 subjects with essential hypertension and no diabetes. Urinary albumin excretion and Sokolow index correlated significantly (r = 0.483; P = 0.0001). Five subjects were positive for microalbuminuria (> 30 mg/24 h) and Sokolow index (> 35 mm); 43 were negative for both, with a concordance rate of 77 percent (chi-squared test 11.1; P = 0.0009). Stepwise multivariate regression analysis indicated two independent determinants for urinary albumin excretion: Sokolow index (F = 18.29), and diastolic blood pressure (F = 12.23). The relationships between urinary albumin excretion, Sokolow index, and blood pressure were not different in the 18 subjects taking angiotensin I-converting enzyme inhibitors and in the 46 others. The close relationship between urinary albumin excretion and Sokolow index observed in this study suggests that left ventricular hypertrophy due to hypertension may account for the increased cardiovascular mortality observed in non diabetic subjects with microalbuminuria.

[Increase of activity of angiotensin-converting enzyme in insulin-dependent diabetic patients with permanent microalbuminuria]

Angiotensin I Converting Enzyme (ACE), which is synthesized by vascular endothelial cells, can be elevated in some diabetic subjects. To study if serum ACE can be elevated in subjects with high risk for malignant microangiopathy, 34 normotensive type I, insulin-dependent diabetic subjects with persistent microalbuminuria (30-300 mg/24 h) were compared for serum ACE activity (Liebermann's method) with 30 normotensive, normoalbuminuric type I, insulin-dependent diabetic subjects of same age (33 +/- 15 (M +/- SD) vs 39 +/- 14 years), sex (13 F/21 M vs 15 F/15 M), stage of retinopathy (14 vs 16 nil/11 vs 7 background/6 vs 4 preproliferative/3 vs 3 proliferative), HbA1c (7.7 +/- .9 vs 8.2 +/- 1.0%). Serum ACE activity of diabetic subjects were also compared with 120 age and sex related healthy controls. Serum ACE activity was higher in type I, insulin-dependent diabetic subjects with microalbuminuria than in those with normoalbuminuria (406 +/- 114 vs 359 +/- 97 IU/l; p = 0.05), or in controls (307 +/- 95 IU/l; p = 0.0001). Normoalbuminuric subjects also had higher ACE activity than controls (p = 0.02). In diabetic subjects, serum ACE activity was not related to diabetes duration (r = 0.1; ns), stage of retinopathy (r = 0.06; ns), HbA1c (r = 0.02; ns), or to blood pressure (r = 0.03; ns), but was related to urinary albumin excretion (r = 0.28; p = 0.03) in diabetic subjects. However, stage of retinopathy was related to diabetes duration (r = 0.74; p = 0.0004) and to age (r = 0.42; p = 0.003) in these subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Serum lipids and urinary albumin excretion in non insulin-dependent diabetics

The increase of urinary albumin excretion has a predictive value for cardiovascular disease in insulin-dependent and non insulin-dependent diabetics. To study the relationship between urinary albumin excretion and serum lipids, 380 non insulin-dependent diabetics, 40 to 75 yr old, with urinary albumin excretion from 0 to 200 mg/l, and normal serum creatinine (less than 150 mumol/l), were surveyed. Urinary albumin excretion, was related positively to age (r2 = 0.014; p = 0.02), to systolic blood pressure (r2 = 0.073, p = 0.0001) and diastolic blood pressure (r2 = 0.052, p = 0.0001); a negative correlation existed with HDL-cholesterol (r2 = 0.043, p = 0.0001) and Apoprotein A1 (r2 = 0.044, p = 0.0001). A stepwise regression analysis was performed and resulted in three independently contributing variables related to urinary albumin excretion: First systolic blood pressure (F = 36), second Apoprotein A1 (F 24), third hemoglobin A1C (F = 6). The presence of hypertension or insulin therapy did not modify these findings. In conclusion, serum lipid seems an important determinant of urinary albumin excretion in non insulin-dependent diabetics.

[Dissociation of hypotensive and renal hemodynamic effects of an angiotensin converting enzyme inhibitor in insulin-dependent diabetic patients with incipient nephropathy]

The mechanism of action of angiotensin converting enzyme (ACE) inhibitors on urinary albumin excretion (UAE) in diabetics is controversial. In order to dissociate the hypotensive and intrarenal effects, 16 insulin-dependant diabetics with permanent microalbuminuria (30-300 mg/24 h) without hypertension were given Ramipril, a long acting ACE inhibitor, at hypotensive (treatment A 5 mg/day; N = 8) and at sub-hypotensive doses (treatment B, 1.25 mg/day; N = 8) over a 6 week period in parallel double-blind study. Blood pressure, UAE, glomerular filtration renal blood flow (continuous 125I-Iodothalamate + 131I-Hippurate infusion) and converting enzyme activity (Liebermann's method), before and after treatment. In treatment group A, the blood pressure fell from 133 +/- 5/79 +/- 4 (mean +/- SE) to 125 +/- 4/77 +/- 2 mmHg (p less than 0.05 for systolic blood pressure) whereas it remained stable in treatment group B (132 +/- 7/79 +/- 4 to 128 +/- 5/80 +/- 4 mmHg). The UAE decreased in both groups: group A from an average of 74 (40-198) to 47 (5-202) mg/24 h (p = 0.07; group B, from an average of 77 (50-136) to 19 (15-120) mg/24 h (p less than 0.005), as did ACE activity: group A from 332 +/- 44 to 163 +/- 33 iu/l (p less than 0.004), group B from 423 +/- 39 to 191 +/- 28 iu/l (p less than 10-4).(ABSTRACT TRUNCATED AT 250 WORDS)

Lipids and fatty acids of tachyzoites and purified pellicles of Toxoplasma gondii

Various lipids were extracted from tachyzoites and from purified pellicles of Toxoplasma gondii. Extracts from both sources were found to have a low cholesterol/phospholipid ratio. The major phospholipid in these fractions was phosphatidylcholine associated with a low amount of sphingomyelin. Oleic acid represented one-third of whole-cell fatty acids and 44% of pellicular fatty acid content. The lipid composition of the pellicle of T. gondii is consistent with the previously reported high fluidity of this membrane.

[Urinary excretion of albumin and lipid abnormalities in hypertensive insulin-dependent diabetics]

Patients with insulin dependent diabetes mellitus (IDDM) often suffer from cardiovascular diseases as renal failure occurs. Elevated albumin excretion rate (AER) is a predictive value of this event. Relations between AER, blood pressure, serum lipids and apoproteins concentrations in 100 patients with IDDM have been surveyed. Twenty one hypertensive patients (HT group) were compared to 21 patients without hypertension (n HT group), matched for sex, age, diabetes duration, and metabolic control, assessed by glycosylated haemoglobin. Comparison of both groups showed HT group had elevated systolic blood pressure (137 +/- 12 vs 126 +/- 20 mmHg; p less than .05), elevated diastolic blood pressure (80 +/- 7 vs 71 +/- 8 mmHg; p less than .001), increase in AER (27 range 3-4023 vs 6 range 2-51 mg/day; p less than .001), slightly elevated serum creatinine (95 +/- 32 vs 78 +/- 15 mumol/l; p less than .05). In HT group, serum lipid composition showed: raise in total cholesterol (251 +/- 43 vs 221 +/- 41 mg/dl; p less than 0.5), elevated apoprotein B (130 +/- 30 vs 99 +/- 21 mg/dl; p less than .001) elevated apoprotein B/apoprotein A1 ratio (.91 +/- .32 vs .66 +/- .27; p less than .001), elevated triglycerides (157 +/- 53 vs 98 +/- 43 mg/dl; p less than .005) and elevated LDL-cholesterol (170 +/- 42 vs 143 +/- 33 mg/dl; p less than .05). Levels of apoprotein A1 and HDL-cholesterol were not significantly different. Body mass index, daily insulin requirement and tobacco usage were similar in both groups.(ABSTRACT TRUNCATED AT 250 WORDS)

[In vitro effects of 1,25-dihydroxycholecalciferol on alkaline phosphatase and gamma-glutamyltransferase activity in hypophysectomized rats]

Effects in vitro of 1,25-dihydroxycholecalciferol (1,25-(OH)2D3) on alkaline phosphatase (PAL), gamma-glutamyltransferase (gamma-GT) and acid phosphatase (PAC) activities were investigated on renal cortex from hypophysectomized rats. In these animals the biosynthesis of 1,25-(OH)2D3 and the specific activities of kidney PAL and gamma-GT were decreased. The course of these effects was determined from 45 min to 8 h. In the presence of 1,25-(OH)2D3 (2 x 10(-6) M) a delayed (5h) but simultaneous stimulation of the three enzymes was observed. It reached a maximum at 6h and disappeared at 8h. The dose-response relation was studied at 6h. In the presence of 1,25-(OH)2D3 (5 x 10(-7) M), the three enzymes were activated. The effect was maximal at 10(-6) M; it was +22% for PAL, +17% and +15% respectively for gamma-GT and PAC compared with controls. Cycloheximide suppressed the induction of PAL but not of gamma-GT activity. The effects of the secosteroid on renal enzymes seems to be a pharmacological more than a physiological one.

Effects of keto-analogues on phosphocalcic and aminoacid metabolism in dialysed patients: a crossover study

It has been suggested that calcium salts of keto-analogues (KA) have beneficial effects on phosphocalcic and aminoacid (AA) metabolism. To confirm this, their short-term effects were evaluated on chronic dialyzed patients. In a prospective, randomised, crossover study, eight and seven patients were put on KA (200 mg/kg/d) and assigned either a low-protein diet (LP:0.4 g/kg/d) or a normal one (NP: 1 g/kg/d) for 15 days. The two treatments were interchanged after 15 days of washout. KA.LP was accompanied by: a) decreases in calorie intake (12%; p = 0.001) and in blood concentrations of albumin (5%, p = 0.004), urea (32%, p = 0.001), phosphate (29%, p = 0.001), parathormone (27%, p = 0.008), isoleucine (24%, p = 0.04), 1 and 3 methyl-histidine (71%, p = 0.03; 24%, p = 0.005), valine (19%, p = 0.004) and hydroxyproline (85%, p = 0.009); b) increases in calcemia (9%, p = 0.002), cystathionine (991%, p = 0.0001) and threonine (22%, p = 0.04). KA.NP was accompanied by: a) decreases in phosphatemia (15%, p = 0.03) and parathormone (18%, p = 0.06); b) increases in calcemia (9%, p = 0.002), cystathionine (427%, p = 0.0001), and phenylalanine (28%, p = 0.013). Calcium salts of keto-analogues together with a low or normal protein diet thus seem to reduce blood concentrations of phosphates and parathormone, and raise calcium; however their action on aminoacids needs further investigation.

Reactivity of HDL subfractions towards lecithin-cholesterol acyltransferase. Modulation by their content in free cholesterol

(1) Human HDL2 (d 1.070-1.125) and HDL3 (d 1.125-1.21) labelled with unesterified [14C]cholesterol, were incubated with a source of lecithin-cholesterol acyltransferase. For optimal activity, the reaction required the addition of albumin in excess, at least 3-times greater than the concentration of HDL-free cholesterol. Under such conditions, the reaction appeared saturable. HDL3 was found the most efficient substrate and the Vmax values expressed for 1.5 IU LCAT/ml and with an albumin/free cholesterol ratio of 3, were 8.3 nmol free cholesterol esterified/ml per h and 4.1 nmol/ml per h for HDL3 and HDL2, respectively. (2) HDL3 were modified in the presence of VLDL by inducing triacylglycerol lipolysis with a semipurified lipoprotein lipase from bovine milk. The newly formed HDL had gained free cholesterol and phospholipids, so that about 50% of these modified HDL, referred to as light-LIP-HDL3, were reisolated in the HDL2 density range. Light-LIP-HDL3 were enriched mostly in free cholesterol (+ 160%) and in phospholipid (+ 40%). Their reactivity towards LCAT was half-reduced compared to parent HDL3, which correlated well with a decrease in their phospholipid/free cholesterol molar ratio. Moreover, HDL3 artificially enriched in free cholesterol and exhibiting a comparable PL/FC behaved like lipolysis-modified HDL in their reactivity towards LCAT. (3) HDL3 were also modified by co-incubation with VLDL (post-VLDL-HDL3), or with VLDL and a source of lipid transfer protein (CET-HDL3). The latter treatment greatly affected the lipid composition of the core particle (-25% esterified cholesterol, +190% TG). In both cases, the moderate decreasing LCAT reactivity observed could be related to the phospholipid/free cholesterol ratio. Thus, like in artificial substrates, the lipid composition of the HDL surface may control the rate of LCAT-mediated cholesterol esterification.

[In vitro stimulation of alkaline phosphatase and gamma- glutamyltransferase in the kidney of hypophysectomized rat by the mixture of 1,25 and 24,25 dihydroxycholecalciferols]

The present study was undertaken to investigate the in vitro effects of two cholecalciferol metabolites 1,25(OH)2CC and 24,25(OH)2CC on the renal cortex alkaline phosphatase (ALP), gamma-glutamyltransferase (GGT) and acid phosphatase (ACP) activities in hypophysectomized rats. We found that both 1,25-CC and 24,25-CC stimulated ALP and GGT. An additive effect was obtained on ALP and GGT after incubation with one with the other metabolites. When 1,25-CC was used alone, it increased ACP; in presence of 24,25-CC, this stimulating effect disappeared. In the rat, together 1,25-CC and 24,25-CC correct in vitro ALP and GGT activities decreased by hypophysectomy. Physiological signification of these effects remains again unknown.

Absence of functional messenger RNA for glycogen phosphorylase in the muscle of two patients with McArdle's disease

(1) Two unrelated cases of McArdle's disease (glycogen storage disease type V, deficiency in muscle-type glycogen phosphorylase, EC.2.4.1.1) with no detectable inactive protein, and two heterozygous relatives of one patient, have been investigated for the presence or absence of functional messenger RNA. Methods were developed and scaled down to be compatible with clinical-size biopsies. (2) Total muscle RNA was prepared and translated in a rabbit reticulocyte cell-free system. Neosynthesized products were isolated by immunoaffinity microchromatography. Phosphorylase was compared with control enzymes neosynthesized and purified under the same conditions. (3) No functional mRNA for phosphorylase could be detected in the muscles of the two patients. A decreased amount of messenger for phosphorylase, compared with the control enzymes, was found in the muscles of the two heterozygotes. (4) Exploration of functional messenger RNA in clinical enzymopathies should be readily adaptable to a number of enzymatic diseases.