Altered Lipid Moieties and Carbonyls in a Wistar Rat Dietary Model of Subclinical Fatty Liver: Potential Sex-Specific Biomarkers of Early Fatty Liver Disease?

Non-alcoholic fatty liver disease (NAFLD) is a condition in which excess fat builds up in the liver. To date, there is a lack of knowledge about the subtype of lipid structures affected in the early stages of NAFLD. The aim of this study was to analyze serum and liver lipid moieties, specifically unsaturations and carbonyls, by nuclear magnetic resonance (NMR) in a subclinical Wistar rat model of NAFLD for detecting early alterations and potential sex dimorphisms. Twelve weeks of a high-fat diet (HFD) induced fat accumulation in the liver to a similar extent in male and female Wistar rats. In addition to total liver fat accumulation, Wistar rats showed a shift in lipid subtype composition. HFD rats displayed increased lipid carbonyls in both liver and serum, and decreased in unsaturated fatty acids (UFAs) and polyunsaturated fatty acids (PUFAs), with a much stronger effect in male than female animals. Our results revealed that the change in fat was not only quantitative but also qualitative, with dramatic shifts in relevant lipid structures. Finally, we compared the results found in Wistar rats with an analysis in a human patient cohort of extreme obesity. For the first time to our knowledge, lipid carbonyl levels and lipoproteins profiles were analyzed in the context of subclinical NAFLD. The association found between lipid carbonyls and alanine aminotransferase (ALT) in a human cohort of extremely obese individuals further supports the potential role of lipid moieties as biomarkers of early NAFLD.

Role of selenium in type 2 diabetes, insulin resistance and insulin secretion

Selenium is a trace mineral essential for life that acts physiologically through selenoproteins. Among other actions, the endogenous antioxidant selenoprotein glutathione peroxidase and the selenium transporter in blood, selenoprotein P, seem to play an important role in type 2 diabetes mellitus and insulin resistance by weakening the insulin signaling cascade through different mechanisms. Recent findings also suggest that selenoproteins also affect insulin biosynthesis and insulin secretion. This review discussed the role of selenium in type 2 diabetes and the complex interplay between selenoproteins and insulin pathways.

Optimisation of internal contamination monitoring programme by integration of uncertainties

Potential internal contamination of workers is monitored by periodic bioassay measurements interpreted in terms of intake and committed effective dose by the use of biokinetic and dosimetric models. After a prospective evaluation of exposure at a workplace, a suitable monitoring programme can be defined by choosing adequate measurement techniques and frequency. In this study, the sensitivity of a programme is evaluated by the minimum intake and dose, which may be detected with a given level of confidence by taking into account uncertainties on exposure conditions and measurements. This is made for programme optimisation, which is performed by comparing the sensitivities of different alternative programmes. These methods were applied at the AREVA NC reprocessing plant and support the current monitoring programme as the best compromise between the cost of the measurements and the sensitivity of the programme.

Integration of uncertainties into internal contamination monitoring

Potential internal contaminations of workers are monitored by periodic bioassays interpreted in terms of intake and committed effective dose through biokinetic and dosimetric models. After a prospective evaluation of exposure at a workplace, a suitable monitoring program can be defined by the choice of measurement techniques and frequency of measurements. However, the actual conditions of exposure are usually not well defined and the measurements are subject to errors. In this study we took into consideration the uncertainties associated with a routine monitoring program in order to evaluate the minimum intake and dose detectable for a given level of confidence. Major sources of uncertainty are the contamination time, the size distribution and absorption into blood of the incorporated particles, and the measurement errors. Different assumptions may be applied to model uncertain knowledge, which lead to different statistical approaches. The available information is modeled here by classical or Bayesian probability distributions. These techniques are implemented in the OPSCI software under development. This methodology was applied to the monitoring program of workers in charge of plutonium purification at the AREVA NC reprocessing facility (La Hague, France). A sensitivity analysis was carried out to determine the important parameters for the minimum detectable dose. The methods presented here may be used for assessment of any other routine monitoring program through the comparison of the minimum detectable dose for a given confidence level with dose constraints.

Efficient gene transfer in mouse neural precursors with a bicistronic retroviral vector

Gene transfer into neural precursors is a powerful approach to study the function of specific gene products during nervous system development. Here we describe a retrovirus-based methodology to transduce foreign genes into mouse neural precursors. We used a high-titer bicistronic retroviral vector that encodes a marker gene, placental alkaline phosphatase (plap), and a selection gene, neomycin phosphotransferase II (neoR), under the translational control of two retroviral internal ribosome entry segments. Transduction efficiency even without selection was up to 95% for multipotential neurospheres derived from embryonic striata and grown with basic fibroblast growth factor 2. Expression of plap and neoR was sustained with time in culture and upon differentiation into neurons, astrocytes, and oligodendrocytes, as shown by double immunofluorescence labeling with cell type-specific markers, Western blotting, and neomycin resistance. However, levels of plap were decreased in differentiated oligodendrocytes. Transduction with the same vector of neonatal oligodendrocyte precursors grown in oligospheres consistently resulted in a lower proportion of plap-immunoreactive cells and enhanced cell death in the absence of neomycin. However, plap expression was maintained in some differentiated oligodendrocytes expressing galactocerebroside or myelin basic protein. In that neurospheres can be easily expanded in vitro and factors enabling their differentiation into the three main central nervous system cell types are being elucidated, this methodology could be used in the future to produce large number of transduced, differentiated neural cells.

Apoptosis in the central nervous system of cerebral adrenoleukodystrophy patients

The childhood cerebral form of adrenoleukodystrophy (ALD) is a fatal demyelinating disease, yet mice deficient in the ALD gene do not show such clinicopathological phenotype. We have therefore investigated in human autopsy tissues whether the ALD gene mutation results in apoptosis of CNS cells. Specimens from telencephalic and brainstem regions of four patients, and three controls were examined for internucleosomal DNA fragmentation, in situ detection of DNA breaks by the TUNEL method, and caspase-3 immunostaining. None of the controls showed significant apoptosis in white matter, while apoptotic nuclei with chromatin alterations were detected in areas of active demyelination in three ALD patients. A large proportion of apoptotic cells were oligodendrocytes and some express activated caspase-3. TUNEL-positive nuclei and/or caspase-3 staining were also detected in perivascular infiltrates and, occasionally, in neurons. We conclude that apoptosis of oligodendrocytes may account, at least in part, for the demyelinating process in the ALD brain.

Differential signalling of the chemokine receptor CXCR4 by stromal cell-derived factor 1 and the HIV glycoprotein in rat neurons and astrocytes

CXCR4 is the Gi protein-linked seven-transmembrane receptor for the alpha chemokine stromal cell-derived factor 1 (SDF-1), a chemoattractant for lymphocytes. This receptor is highly conserved between human and rodent. CXCR4 is also a coreceptor for entry of human immunodeficiency virus (HIV) in T cells and is expressed in the CNS. To investigate how these CXCR4 ligands influence CNS development and/or function, we have examined the expression and signalling of this chemokine receptor in rat neurons and astrocytes in vitro. CXCR4 transcripts and protein are synthesized by both cell types and in E15 brain neuronal progenitors. In these progenitors, SDF-1, but not gp120 (the HIV glycoprotein), induced activation of extracellular signal regulated kinases (ERKs) 1/2 and a dose-dependent chemotactic response. This chemotaxis was inhibited by Pertussis toxin, which uncouples Gi proteins and the bicyclam AMD3100, a highly selective CXCR4 antagonist, as well as by an inhibitor of the MAP kinase pathway. In differentiated neurons, both SDF-1 and the glycoprotein of HIV, gp120, triggered activation of ERKs with similar kinetics. These effects were significantly inhibited by Pertussis toxin and the CXCR4 antagonist. Rat astrocytes also responded to SDF-1 signalling by phosphorylation of ERKs but, in contrast to cortical neurons, no kinase activation was induced by gp120. Thus neurons and astrocytes can respond differently to signalling by SDF-1 and/or gp120. As SDF-1 triggers directed migration of neuronal progenitors, this alpha chemokine may play a role in cortex development. In differentiated neurons, both natural and viral ligands of CXCR4 activate ERKs and may therefore influence neuronal function.

[Effect of digestion on the immunoglobulin G concentration in the intestinal contents of replete Boophilus microplus females]

In the present paper it was determined the concentration of immunoglobulin G in extracts from gut of female Boophilus microplus engorded during the first 7 days of the second stage of continual digestion by using the simple radial immunodiffusion technique. It was also measured the concentration of hemoglobin by spectrophotometric methods. The analysis of correlation between both variables made during the study was positive and significant for p < 0.05. The analysis of simple variance and the application of Duncan's test resulted in a marked reduction of the concentrations of hemoglobin in the gut from the 5th day of study, which is connected with the beginning of the active process of oviposition, and in an important decrease of the concentration of immunoglobulin from the 7th day of the study. Though there is a trend to diminish in the concentrations of both blood proteins, the proteolysis of the IgG by gut extracts could not be produced in vitro.

Proliferative glomerulonephritis revealing chronic Q fever

We describe the case of a 69-year-old male with a year-long history of renal failure. Investigation revealed proliferative glomerulonephritis, cryoglobulinemia, and Q fever endocarditis. Renal tissue examination for the presence of Coxiella burnetii was positive. The patient was treated by doxycycline and chloroquine; his clinical status, renal failure, and chronic Q fever have dramatically improved.

Accelerated hypertension and nephroangiosclerosis associated with antiphospholipid syndrome. Report of two cases and review of the literature

We describe two patients with the primary antiphospholipid syndrome who presented with severe hypertension. Renal biopsy specimen provided histologic evidence of intra-renal vascular disease with intravascular microthrombosis and nephrosclerosis, without feature of proliferative glomerulopathy. Accelerated hypertension and nephroangiosclerosis might indeed be one of the complications associated with anticardiolipin antibodies. The mechanism responsible might be the interaction of anticardiolipin antibodies, platelets and endothelial cell leading to microthrombi formation and increased local mitogenic activity that attract and stimulate neighbouring smooth muscle cell and fibroblast proliferation.

Histoenzymatic study of human renal tissue preservation: I--Proximal tubular glucose-6-phosphatase is correlated with transplant evolution

Glucose-6-phosphatase was tested histochemically as a gluconeogenesis marker of ischemia-reperfusion injury of proximal tubular cells in human renal transplants. Histochemical enzyme activity, histology and transplantation conditions (preservation solution, cold and warm ischemia time, donor age), were compared to renal transplant evolution. Neither histology nor transplantation conditions were correlated with renal transplant evolution. Only glucose-6-phosphatase activity was significantly correlated with transplant evolution and could be used as a more sensitive marker than histology for the detection of ischemia-reperfusion injury of proximal tubules.

[Crescentic glomerulonephritis and primary Gougerot-Sjögren syndrome]

Glomerulonephritis complicating primary Gougerot-Sjögren's syndrome is extremely rare. We report the case of a 72-year old woman with primary Gougerot-Sjögren syndrome complicated by progressive renal failure. Kidney biopsy revealed a crescentic glomerulonephritis. A rapid improvement occurred with corticosteroids. This observation is, at our knowledge, the first case of crescentic glomerulonephritis described during this disease. A review of the literature concerning glomerulonephritis complicating primary Gougerot-Sjögren syndrome is reported.

Evidence that human kidney produces a protein similar to lithostathine, the pancreatic inhibitor of CaCO3 crystal growth

Pancreatic juice is supersaturated in calcium carbonate. CaCO3 crystal growth is controlled by lithostathine, a secretory protein synthesized by pancreatic acinar cells, first described as a constituent of pancreatic stones. It was recently reported that, in the thin descending limb of the Henle's loop, urine was supersaturated in CaCO3 (Coe FL, Parks JH: Defenses of an unstable compromise: crystallization inhibitors and the kidney's role in mineral regulation. Kidney Int. 1990: 38, 625-631. This observation suggested the presence in kidney of a similar inhibitor. In this study, we show that a protein immunologically related to lithostathine is actually present in urine of healthy subjects and in renal stones. Immunocytochemistry of kidney sections localized the protein to cells of the proximal tubules and thick ascending limbs of the Henle's loops. Protein extracts of renal stones inhibited CaCO3 crystal growth in vitro and this inhibition was significantly lifted by incubating the extracts with antibodies to lithostathine. The protein is not immunologically related to nephrocalcin. Because of its structural and functional similarities with pancreatic lithostathine, it was called renal lithostathine.

Kidney biopsy findings in cyclosporine-treated patients with insulin-dependent diabetes mellitus

Renal biopsy specimens of 40 patients with recent-onset insulin-dependent diabetes mellitus treated with cyclosporine (CSA) for 6-29 months were examined. Cyclosporine-associated chronic vascular interstitial toxicity of moderate intensity was found in 10 patients (25%). The most prominent lesions were interstitial fibrosis and tubular atrophy. Arteriolopathy was less pronounced and glomerular damage unremarkable. A significant correlation exists between the extent of tubular atrophy and CSA trough whole blood levels. These data indicate that the development of CSA-associated chronic nephropathy is dose-dependent.

Effect of secretin on portal venous flow

In this study we evaluated the effect of two different doses of secretin on portal haemodynamics (by pulsed Doppler associated with real time ultrasound) in 24 healthy humans. In 12 subjects (group A) we administered an intravenous dose of 75 clinical units of secretin and in the remaining 12 (group B) a dose of 20 CU. In all subjects the following parameters were studied before, during, and for 10 minutes after secretin administration: (a) calibre of the portal vein, (b) mean velocity of portal venous flow, and (c) volume of portal venous flow. In three subjects in each group we also evaluated the changes in flow in the superior mesenteric artery. Secretin injection induced a slight increase in both groups in comparison to basal values of portal vein calibre (mean of maximal per cent increase +25% in group A, not significant, and +16.7% in group B, not significant) and a noticeable increase of mean velocity (mean of maximal per cent increases +61.4% in group A, p less than 0.005, and +65.4% in group B, p less than 0.01) and flow volume (mean of maximal per cent increase +127% group A, p less than 0.005, and +114% group B, p less than 0.005). The magnitude of the haemodynamic changes did not differ significantly between the two groups. Doppler investigation of the superior mesenteric artery showed a marked increase of flow velocity (mean of maximal per cent increase +218% in group A and +246% in group B) and flow volume (mean of maximal per cent increase +276% in group A and +311% in group B). These data suggest that secretin has an appreciable vasoactive effect and induces a significant increase in portal venous flow even at doses much lower than those necessary for a maximal stimulation of exocrine pancreatic secretion.

Correlation between laminin and type IV collagen distribution in breast carcinomas, and estrogen receptors expression, lymph node and vascular involvement

The laminin (Lam) and type IV collagen (Coll IV) and estrogen receptor (ER) immunodetections were assessed in a large series of 400 human breast carcinomas. In all the cases the patient's age, the tumor size, the histological type and grade, the presence or the absence of axillary lymph node metastasis and of vascular invasion in tumor borders, and ER tumor content were recorded. Monoclonal anti-Lam, anti-Coll IV were applied with the avidin-biotin-peroxidase complex and monoclonal anti ER with peroxidase anti-peroxidase complex, on frozen sections. A computerized system of image analysis referred to as SAMBA (TITN) with specific software for tissue sections analysis permitted a multiparametric quantitative analysis of immunostained surfaces. With this system, in each tumor, the cellularity, the percentage of Lam, Coll IV and receptor positive surfaces versus the total cell surface and versus the epithelial (keratin positive) surface, the integrated optical density IOD histograms were obtained and correlated to morphometrical and standard histological data. From this study, it was shown that: (1) Lam and Coll IV immunostained epithelial basement membranes in carcinomas were correlated to the presence of estrogen and progesterone receptor antigenic sites within the tumors, with a significant decrease of the positive staining in ER-ICA negative tumors in comparison to ER-ICA/PR-ICA positive tumors. (2) The combined densitometric and morphometric evaluation demonstrated a decrease of Lam and Coll IV immunostaining in malignant tumors, correlated to (i) the presence of peritumorous vascular invasion and (ii) keratin positive cells in bone marrow (iii) axillary lymph node involvement. It is concluded that the variations in Lam and Coll IV antigens distribution may be relevant indicators of tumor metastatic potential in breast carcinomas and that computerized image analysis enables the standardization of the evaluation antigens distribution.

Inhibition of caerulein-induced gall bladder emptying by cimetropium bromide in humans

The effect of cimetropium bromide, a new potent antimuscarinic compound, on caerulein-induced gall bladder emptying in 8 male volunteers was studied by real time ultrasonography. During saline infusion, caerulein (10-40 ng.kg-1.h-1) induced dose-dependent emptying of the gall bladder. There was a significant linear correlation between the dose of the peptide and the reduction in gall bladder size. A continuous infusion of cimetropium bromide (5 mg.h-1) significantly inhibited the contracting effect of caerulein on the human gall bladder, by 74% in response to the lowest dose and by 45% and 22%, respectively, to the two higher doses. The data confirm that the contracting effect of CCK-like peptides on the human gall bladder is at least partly cholinergically mediated, and they demonstrate the relaxing activity of cimetropium previously shown in animals. Provided its antispasmodic activity is also evident in disease, cimetropium should be regarded as a potentially useful agent for the treatment of biliary colic and spasm of the biliary tree.

Glomerulonephritis in dogs with canine leishmaniasis

Kidney specimens, obtained from 11 dogs of diverse species that had contracted spontaneous leishmaniasis, were submitted to a histopathological investigation using a classical preparation of sections embedded in paraffin, semi-thin and ultra-thin sections embedded in plastic, and sections frozen under immunofluorescence. Eight animals presented moderate to severe renal insufficiency. Two major categories of glomerular lesions were identified in the kidneys examined: acute glomerulonephritis and extra-membranous glomerulonephritis. These two categories were never associated and no transition from from one to the other was found. Immune complex deposits prevailed sharply over proliferative phenomena, which remained infrequent. Study of these glomerulonephrities could represent a model for better understanding of the immunological aspects of leishmaniasis.

[Familial deficiency of complement factor 7: association with bacterial meningitis. Apropos of 3 recent cases]

Three recent cases of inherited deficiency of the seventh component of complement (C7) associated with recurrent infectious meningitis are described. Two cases were associated with meningococcal meningitis, the third is the first case report of C7 inherited deficiency associated with Haemophilus parainfluenzae meningitis. Family studies are consistent with inheritance and non-HLA-linked, autosomal codominant trait of the C7 deficiency. The three patients have remained well, following antibiotic treatment.

Morphological and hemodynamic changes in the portal venous system after distal splenorenal shunt: an ultrasound and pulsed Doppler study

We investigated a group of patients who underwent distal splenorenal shunt using high-resolution real-time equipment and a duplex scanner with the aims: (i) to evaluate the rate of visualization of shunt; (ii) to assess change in size in the portal vein, and (iii) to characterize the flow pattern in the splenic vein and to study flow direction and velocity in the portal vein, thus adding new data on the efficacy of this operation in maintaining hepatic perfusion. Real-time ultrasonography was performed in 29 patients before surgery, after 7 to 30 days and after 4 to 12 months. Direct visualization of the shunt was achieved in 53.5% of the patients. Mean caliber of the portal vein significantly decreased after the operation: preoperative = 1.52 +/- 0.32; after 7 to 30 days = 1.32 +/- 0.16 (p less than 0.001), and after 4 to 12 months = 0.99 +/- 0.19 (p less than 0.001). The overall postoperative incidence of portal thrombosis was 22.2%. Thirteen of these patients also underwent a postoperative (4 to 36 months) pulsed Doppler investigation. Flow towards anastomosis was demonstrated in the splenic vein in 11 patients, and in 7 cases, typical caval pulsatility was observed. Decreased hepatopetal flow in the portal vein was found in 10 of 13 patients. In two patients, no flow was detectable and in the other the flow was hepatofugal. On the basis of our data, we can affirm that pulsed Doppler investigation may provide useful data for the evaluation of shunt patency and preservation of a decreased portal hepatic perfusion in the majority of patients.

Primary gastric lymphoma versus gastric carcinoma: endoscopic US evaluation

Endoscopic ultrasonography (US) enables high-resolution imaging of the stomach and can demonstrate the different layers of the gastric wall. It has therefore been proposed for use in evaluating the extension of gastric neoplasms. It was performed in nine patients with primary gastric non-Hodgkin lymphoma and in 36 with gastric carcinoma. The US and pathologic findings were correlated in three surgical specimens of gastric lymphoma. Three different US patterns were found in gastric lymphomas: a polypoid pattern (two cases), localized (two cases) or extended (five cases) hypoechoic infiltration, and thickening with superficial ulcerations. Infiltration was confined to the second and third layers of the gastric wall in six cases and was transmural in three. The study of the gastric lymphoma specimens confirmed the accuracy of US in demonstrating the extent of infiltration. Gastric carcinomas had a more echogenic pattern and a different trend of diffusion, with no extended longitudinal hypoechoic infiltration of the superficial layers or extended hypoechoic transmural infiltration.

[Vasculorenal accidents in pregnancy. Prognostic value of renal biopsy]

Our study is an attempt to determine whether, after a vasculo-renal accident (VRA) in pregnancy, renal biopsy (RB) is of interest to determining the outcome specially of blood pressure. Starting from the 201 RB we systematically performed in such patients we may conclude: first, the onset of clinical and biological troubles do not allow to postulate the existing kidney lesions. Minimal changes observed in 31 women appeared early 9 times and during the last trimester 22 times. Most of the cases observed were preeclampsia (n = 108). The clinical or biological troubles were observed 44 times within the first months of the pregnancy and in 64 patients at the end of it. A specific group isolated concerns predominant vascular lesions (n = 44). Forward troubles were observed 16 times and 28 times during the third trimester. Second: a follow up has been possible for 1 to 5 years in 145 patients. A permanent hypertension occurred out of the 80 preeclamptic women, meanwhile among the 40 women with predominant vascular lesions, 60 p. 100 developed a permanent hypertension. Thus RB provides interesting data on renal lesions revealing sometimes (n = 18) a specific nephropathy (most of them were a glomerulopathy). Furthermore predominant vascular lesions suggest hypertension to recur in later pregnancy or become permanent.

Clinical correlation between hypercoagulability and thrombo-embolic phenomena

A study of the coagulolytic balance as well as platelet aggregation was carried out in 64 nephrotic patients. The data were correlated, in a prospective attempt, with the clinical demonstration of thrombo-embolic events. Activating factors (factors I, VIIIc, VIIIr:Ag) were increased as well as certain clotting inhibitors, alpha-1-antitrypsin and alpha-2-macroglobulin. There was a platelet hyperaggregability in 31.5% of our patients. Thrombo-embolic complications occurred in six subjects (9%). The data of these six patients were compared with that of the other patients; no significant correlation were found between clotting abnormalities and thrombosis. Low level of ATm (less than 0.8 U.Fr) and severe hypoalbuminemia (less than 20 g/liter) were of no predictive value for the occurrence of thrombo-embolic events.

Effect of somatostatin and thyrotropin-releasing hormone on cholecystokinin-induced gallbladder emptying

The effect of somatostatin (0.05 and 1.5 micrograms/kg/hr) and of thyrotropin-releasing hormone (0.1 and 1.0 microgram/kg/hr) on cholecystokinin-induced gallbladder emptying was studied in healthy volunteers by means of real-time ultrasonography. In addition, the action of increasing doses (0.05, 0.15, 0.45, and 1.35 micrograms/kg/hr) of somatostatin on resting gallbladder volume was also evaluated. Somatostatin, at the dose of 0.05 microgram/kg/hr (shown to produce blood levels similar to those measured after a meal) significantly inhibited the gallbladder contraction in response to cholecystokinin. Kinetic analysis showed that the interaction of somatostatin and cholecystokinin is of the noncompetitive type. The higher dose of the peptide (1.5 microgram/kg/hr) completely suppressed cholecystokinin-induced gallbladder contraction. In experiments carried out using somatostatin alone, a progressive increase in gallbladder volume in response to increasing doses of peptide was observed. The administration of either dose of thyrotropin-releasing hormone did not affect gallbladder emptying in any of the subjects studied. It is concluded that somatostatin is a potent inhibitor of cholecystokinin action on the gallbladder. The clear effectiveness of a very low, presumably physiological, dose indicates that somatostatin may play a physiological role in the regulation of gallbladder motor activity and provides further evidence that the peptide may act as a true hormone in man. Thyrotropin-releasing hormone does not seem to affect gallbladder motility, at least under the experimental conditions of the present study.