AB0059 STUDY OF THE ANTI-INFLAMMATORY EFFECT OF CINNAMOMUM VERUM IN RATS

Background:

Inflammatory response is a common physiological response that protects the host of many harmful stimuli such as toxins, local injuries and pathogens. Today, non-steroidal anti-inflammatory drugs are the most commonly prescribed for the treatment of many inflammatory treatments. However, long term administration of these NSAIDs causes many adverse effects, including gastrointestinal ulcers and bleeding and kidney damage. Therefore, the need for new anti-inflammatory drugs with fewer side effects is required.

Objectives:

The aim of our study was to evaluate the anti-inflammatory activity of Cinnamomum verum (C. Verum) on rats while testing the dose effect and the typical effect of the solvent.

Methods:

The edema was induced by injection of carrageenan solution (CARR) in paw of rats according to the method of Winter et al, 1963. The measurements of volumes of right hind paw of each rat were taken before induction of edema and each 1 h, 2 h, 3 h, 4 h and 5 h after the injection of carrageenan. 7 groups of 6 rats received, one hour before the injection of the carrageenan, different treatment: G1= witness, G2=CARR + saline solution, G3= CARR+ Acetylsalicylic acid, G4= CARR + C. verum- MeOH 100, G5= CARR + C. verum- MeOH 300, G6= CARR + CARR + C. verum- EtOH 100 and G7= CARR + C.verum- EtOH 300.

Results:

For this test, the volume of edema increases with time, this increase is greater in the group treated with saline solution than with the extracts of C.Verum and with Acetylsalicylic acid. The extracts of C. Verum administered intraperitoneally one hour before the injection of the carrageenan, reduced the edema in the third hour after.

Conclusion:

The interesting anti-inflammatory activity of Cinnamomum verum recorded in this work may at least in part support its popular use in traditional medicine [1, 2].

References:

[1]Mirza Muhammad Fahd Qadir, Attya Bhatti, Muhammad Usman Ashraf, Mansur Abdullah Sandhu, Sidrah Anjum, Peter John. Immunomodulatory and therapeutic role of Cinnamomum verum extracts in collagen-induced arthritic BALB/c mice. Inflammopharmacology 2018 Feb;26(1):157-170.

[2]Heping Cao, Joseph F Urban Jr, Richard A Anderson. Cinnamon polyphenol extract affects immune responses by regulating anti- and proinflammatory and glucose transporter gene expression in mouse macrophages. J Nutr 2008 May;138(5):833-40.

Disclosure of Interests:

None declared

Metabolic syndrome and physical activity measured by pedometer among adolescents

AIM

To describe the prevalence of metabolic syndrome and to study the association of physical activity measured by pedometer with the metabolic syndrome components, in a sample of overweight and obese adolescents from Sfax City.

METHODS

This study concerned 51 obese and overweight adolescents (28 girls and 23 boys), between the ages of 15 and 18 years, recruited by the unit of obesity and metabolic syndrome department of endocrinology, Hedi Chaker Hospital, University of Sfax, between december 2012 and october 2013. Metabolic syndrome was defined with the International Diabetes Federation (IDF) criteria. Physical activity was monitored with pedometer (Digi-Walker SW-200; Yamax Co, Tokyo, Japan).

RESULTS

The frequency of metabolic syndrome was 21.6%. It was significantly higher in obese (25%) than in overweight (15,81%) adolescents (p=0.04). The most common component, associated with abdominal obesity, was hypoHDLemia observed in 58.8 % of the sample. The average steps / day measured by pedometer was significantly higher in subjects without metabolic syndrome than with (9648, 25±2297, 726 vs 7365, 91±1505, 65 steps/day; p=0, 03). Pedometer determined steps/day was inversely correlated with waist circumference (P<0.05), blood pressure (P<0.05) and triglycerides (P<0.05).

CONCLUSION

Metabolic syndrome is prevalent in our young population. A more physically active lifestyle appears to be associated with lower probability of metabolic syndrome.

Affinity kinetics of leptin-reactive immunoglobulins are associated with plasma leptin and markers of obesity and diabetes

Obese subjects display elevated plasma levels of leptin reflecting the phenomenon of leptin resistance. Here, we aimed to determine whether leptin-reactive immunoglobulins (Ig) are present in obese and type 2 diabetes (T2D) patients and whether their plasma levels and affinity kinetics may correlate with obesity and diabetes markers. We show that leptin levels are increased in obese patients with and without T2D. Although mean plasma levels of leptin-reactive IgG were similar between study groups, IgG in obese non-diabetic patients had increased dissociation rate and lower affinity (increased dissociation equilibrium constant value; KD). In controls and diabetic patients, the association rates of leptin IgG correlated negatively with obesity and diabetes markers, respectively. In contrast, KD values correlated positively with plasma leptin levels and obesity traits in our cohort, and with diabetes markers in both the total cohort and in the obese T2D group. Taken together, our data reveal that leptin-reactive IgG are present in healthy subjects, obese, and diabetic patients but display altered affinity kinetics in obesity. Increased IgG binding to leptin in healthy subjects associated with lower body mass index (BMI) suggests an enhancing role of IgG in leptin signaling. Accordingly, a decreased affinity of IgG for leptin, found in obese patients, can be relevant to leptin resistance.

Potential role of liver enzyme levels as predictive markers of glucose metabolism disorders in a Tunisian population

The relationship between liver enzymes and T2D risk is inconclusive. We aimed to evaluate the association between liver markers and risk of carbohydrate metabolism disorders, as well as their discriminatory power, for T2D prediction. This cross-sectional study enrolled 216 participants classified as normoglycemic, prediabetic, newly diagnosed diabetics, and diagnosed diabetics. All participants underwent anthropometric and biochemical measurements. The relationship between hepatic enzymes and glucose metabolism markers was evaluated by analyses of covariance. The associations between liver enzymes and incident carbohydrate metabolism disorders were analyzed through logistic regression and their discriminatory capacity to predict T2D by ROC analysis. High AP, ALT, γGT, and AST levels were independently related to decreased insulin sensitivity. Interestingly, a higher AP level was significantly associated with an increased risk of prediabetes (p = 0.017), newly diagnosed diabetes (p = 0.004), and T2D (p = 0.007). An elevated γGT level was an independent risk factor for T2D (p = 0.032) and undiagnosed T2D (p = 0.010) in prediabetic and normoglycemic subjects, respectively. In ROC analysis, AP was a powerful predictor of incident diabetes and significantly improved T2D prediction. Liver enzymes within the normal range, specifically AP levels, are associated with increased risk of carbohydrate metabolism disorders and significantly improved T2D prediction.

Detection of Cytokeratin 19 mRNA and CYFRA 21–1 (Cytokeratin 19 Fragments) in Blood of Tunisian Women with Breast Cancer

Cytokeratin 19 (CK19) is an acidic protein of 40 kDa that is part of the cytoskeleton of epithelial cells. It is highly expressed by all epithelial cells and represents a useful indicator of epithelial differentiation. The soluble fragment of CK19 (CYFRA 21–1) can be a useful circulating tumor marker and can be detected in the serum of cancer patients. The development of metastasis in patients with cancer of epithelial origin is due to the migration of tumor cells from the original tumor to distant organs. In order to detect micrometastasis in patients with breast cancer, we evaluated and compared CK19 gene expression using RT-PCR in blood samples collected from 80 healthy women and 80 patients with localized or metastatic breast cancer. The concentration of the soluble CK19 fragment CYFRA 21–1 was measured in serum of all study subjects by radioimmunoassay employing specific monoclonal antibodies. The relationship between the expression of this molecular marker and clinical stage, tumor differentiation and CK19 mRNA transcripts was investigated. We found that CK19 mRNA expression in blood (as a direct index of the presence of circulating tumor cells) was not correlated with CYFRA 21–1.

Modulatory effects of quercetin on liver histopathological, biochemical, hematological, oxidative stress and DNA alterations in rats exposed to graded doses of score 250

This study investigated the morphological, biochemical and molecular aspects of liver injury in rats after the exposure to difenoconazole and the protective effects of quercetin against hepatotoxicity and genotoxicity induced by this fungicide. Rats were given graded doses of difenoconazole associated or not to quercetin daily for 20 days. Our results showed a significant increase in PLT (platelets) and WBC (white blood cells) in rats treated with higher doses of difenoconazole (1/38 and 1/9 of LD50). However, a significant decrease in Hb (hemoglobin) rate and RBC (red blood cells) number in rats treated with higher doses of difenoconazole (1/38 and 1/9 of LD50) was obtained. Besides, difenoconazole treatment caused an increase in hepatic enzyme activities of alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP) and lactate dehydrogenase (LDH). Difenoconazole increased the levels of malondialdehyde (MDA) and advanced oxidation protein products (AOPPs), and decreased superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) activities and vitamin C levels in liver tissues compared to the control group. We also noted a degradation of nucleic acids, testifying difenoconazole genotoxicity. Changes in hepatic tissues were confirmed by histological findings. Co-administration of quercetin (20 mg/kg) improved hematological and biochemical parameters and showed a significant liver protective effect by decreasing MDA levels and producing advanced oxidation protein, along with increased antioxidative enzyme activities and vitamin C levels. Results were confirmed by the improvement of histological impairments. Thus, it appears that quercetin was effective in preventing acute liver injury induced by exposure to difenoconazole.

Effects of vanillin on potassium bromate-induced neurotoxicity in adult mice: impact on behavior, oxidative stress, genes expression, inflammation and fatty acid composition

CONTEXT

Vanillin is known to possess important antioxidant activity.

OBJECTIVE

The current study was conducted to establish the therapeutic efficiency of vanillin against potassium bromate (KBrO₃)-induced depression-like behavior and oxidative stress in mice.

MATERIAL AND METHODS

Mice were exposed during 15 days either to potassium bromate (KBrO₃), KBrO₃+ vanillin or to only vanillin.

RESULTS

Our results revealed a significant modification in the fatty acid composition of the KBrO₃-treated mice. In addition, KBrO₃ induced a significant reduction in enzymatic activities and gene expressions, Na⁺ -K⁺ and Mg²⁺-ATPases, acetylcholinesterase and butylcholinesterase activities. The gene expression of tumor necrosis factor-α, interleukin-1β, interleukin-6 and COX₂, significantly increased in the cerebrum of KBrO₃-treated group. Histopathological observations were consistent with these effects. Co-treatment with vanillin significantly attenuated KBrO₃-induced oxidative stress and inflammation.

CONCLUSION

This work suggests that vanillin mitigates KBrO₃-induced depression, and that this neuroprotective effect proceeds through anti-oxidant and anti-inflammatory activities.

Congenital anomalies in Tunisia: Frequency and risk factors

BACKGROUND

Despite the high risk of recurrence of congenital malformations, there are no well-accepted preventive measures in developing countries like Tunisia. It is recommended that thorough epidemiological studies of congenital anomalies in this country are needed. The aim of this study is to assess the frequency and types of congenital anomalies in Tunisia and research some risk factors associated with occurrence of these anomalies.

METHODS

In this retrospective study, all the fetuses who were autopsied during 21years period from February 1991 to December 2011 (n=9678) at Service of embryofetopathology in the Center of Maternity and Neonatology of Tunis (CMNT) were studied. The classification of malformations was based upon the anatomical system affected. The differences in fetal/maternal characteristics between cases with or without congenital malformations were assessed using Chi² test.

RESULTS

Of the all 9678 autopsied fetuses, 4498 (46.47%) were diagnosed as being malformed fetuses. Anomalies of limbs (22.71%) and digestive and abdominal wall defects (14.76%) were mostly detected, followed by congenital brain defects (13.41%) and nephrourologic abnormalities (11.23%). A marked association of parental consanguinity with increased congenital anomalies rates was found (P<10^-6, OR=1.89, CI=1.69-2.13).

CONCLUSION

In Tunisia, surveillance and epidemiological evaluation of congenital anomalies underline the high frequency of these events. This will help to better target congenital anomalies prevention and screening policies in our population.

Effects of acrylamide graded doses on metallothioneins I and II induction and DNA fragmentation: Bochemical and histomorphological changes in the liver of adult rats

The present study investigates the toxic effects of acrylamide (ACR) administered to rats at two doses on (i) oxidative stress and disruption of pro-oxidant/antioxidant balance in hepatic cells and (ii) its correlation with metallothioneins (MTs) genes expression, DNA damage and histomorphological changes. Treated rats with 20 and 40 mg/kg body weight of ACR led to an increase in malondialdehyde, hydrogen peroxide, advanced oxidation protein products, protein carbonyl levels as well as an alteration in the antioxidant status. Total MT content in the liver and MT I and MT II genes induction were increased. Plasma transaminases activities, albumin, total protein and glucose levels were also increased, while alkaline phosphatase activity was decreased. Moreover, total cholesterol (TC), triglyceride, low-density lipoprotein cholesterol (LDL-C) levels, TC/high-density lipoprotein cholesterol (HDL-C) and LDL-C/HDL-C ratios were increased, while HDL-C decreased in a dose-dependent manner. A random DNA degradation was observed only in the liver of ACR-treated rats with the highest dose. These changes were confirmed by histopathological observations.

How does serum brain natriuretic peptide level change under nasal continuous positive airway pressure in obstructive sleep apnea-hypopnea syndrome?

BACKGROUND

Obstructive sleep apnea-hypopnea syndrome (OSAHS) is associated with cardiovascular morbidity and mortality, which can be improved by using continuous positive airway pressure (CPAP) therapy. However, the pathophysiological links between the two kinds of disease and the mechanism of the CPAP effect remain incompletely understood. We aimed to inquire into the myocardial involvement in this relationship. We suggested that serum brain natriuretic peptide (BNP) is sensitive enough to detect myocardial stress caused by OSAHS.

DESIGN AND METHODS

Sixty-four subjects without cardiovascular disease (21 controls, 24 normotensive OSAHS patients, and 19 hypertensive OSAHS patients) were analyzed for serum BNP at baseline and serially over 6 months. CPAP was applied to 23 patients with severe OSAHS.

RESULTS

At baseline, the serum BNP levels were significantly higher (p=0.0001) in the OSAHS group (22.3±14.79 pg/ml) than in the control group (9.2±6.75 pg/ml). Increased serum BNP levels were significantly associated with mean transcutaneous oxygen saturation (SpO2) (p<0.0001), minimal SpO2 (p=0.002), oxygen desaturation index (p=0.001), and total sleep time spent with SpO2 lower than 90% (p=0.002). All patients with elevated BNP levels (≥37 pg/ml) had moderate or severe OSAHS (11/43 OSAHS patients). The more severe the OSAHS, the higher the BNP levels were. However, only the difference between severe and mild OSAHS was statistically significant (p=0.029). Hypertensive OSAHS patients had the highest baseline BNP levels (27.7±16.74 pg/ml). They were significantly higher (p=0.001) than in normotensive OSAHS patients (18±11.72 pg/ml) (p=0.039) and the controls (9.2±6.75 pg/ml). As compared with baseline, treatment with CPAP significantly decreased BNP levels in both hypertensive and normotensive OSAHS patients (respectively, from 36±16.10 to 29.7±14.29 pg/ml, p<0.001, and from 20±10.09 to 16±8.98 pg/ml, p<0.001). In contrast, the BNP levels slightly increased in the controls (from 9.2±6.75 to 9.5±7.02 pg/ml, p=0.029), but there was no statistically significant difference in comparison with the baseline value. The effect of CPAP on BNP levels was more marked in patients with higher baseline BNP levels and those with the most prolonged nocturnal desaturation (p=0.001, r=0.65). It was also more marked in hypertensive OSHAS patients (p=0.015, r=0.72) in comparison with normotensive OSAHS patients (p=0.03, r=0.62).

CONCLUSION

BNP seems to be sensitive enough to detect myocardial stress caused by OSAHS. As such, it is a potential marker for screening of preclinical cardiovascular damage in patients with untreated OSAHS. Application of CPAP decreases levels significantly in normotensive and particularly in hypertensive OSAHS. These findings are consistent with previous results suggesting the potential benefits of CPAP on cardiovascular outcome in OSAHS patients.

[Psoriasis: physiopathology and immunogenetics]

Psoriasis is a multifactorial disease that involves genetic, immunological and environmental factors. During the last decade, several studies by genome scan on families or cases/controls helped to highlight more than ten loci "PSORS" located on different chromosomes and containing several candidate genes. Psoriasis appears as a genetic disease that follows the mixed model with the involvement of a major gene (PSORS1) and a set of minor genes with a variable penetrance depending on the locus. Genetic data have focused on the involvement of the immune system in the pathogenesis of psoriasis. It is now accepted that psoriasis is an immunological disease involving the response profiles TH1 and TH17. Much remains to be done to better elucidate the mechanisms involved in the genesis of psoriatic lesions to find new therapeutic targets.

A functional autophagy pathway is required for rapamycin-induced degradation of the Sgs1 helicase in Saccharomyces cerevisiae

In yeast Saccharomyces cerevisiae, the immunosuppressant rapamycin mimics starvation by inhibiting the kinase Tor1. We recently documented that this treatment triggers a rapid degradation of Sgs1, a helicase involved in several biological processes such as the prevention of genomic instability. Herein, we show that yeast strains deleted for genes ATG2, ATG9, and PEP4, encoding components of the autophagy pathway, prevent rapamycin-induced degradation of Sgs1. We propose that defects in the autophagy pathway prevent degradation of key proteins in the rapamycin response pathway and as a consequence cause resistance to the drug.

Occurrence of IMP-8, IMP-10, and IMP-13 metallo-β-lactamases located on class 1 integrons and other extended-spectrum β-lactamases in bacterial isolates from Tunisian rivers

BACKGROUND

Antibiotic-resistant bacteria have been surveyed widely in water bodies, but few studies have determined the diversity of antibiotic-resistant bacteria in river waters. This study was undertaken to investigate the origin of resistance among polluted river bacterial isolates in Tunisia.

METHODS

In this study 128 isolates resistant to β-lactam antibiotics were obtained from 2 polluted rivers in the north of Tunisia. Isolates were identified using Phoenix phenotyping criteria. The occurrence of bla(TEM), bla(SHV), bla(CTX-M), bla(CMY), bla(VIM), and bla(IMP) was studied by polymerase chain reaction (PCR) amplification and sequencing, and the genetic relatedness of the 16 IMP-producing Klebsiella pneumoniae isolates was analyzed by comparison of XbaI pulsed-field gel electrophoresis (PFGE) profiles.

RESULTS

Using Phoenix phenotyping criteria, diverse genera of bacteria were identified with different rates of prevalence and with different minimum inhibitory concentrations against different antibiotics. The occurrence of bla(TEM), bla(SHV), bla(CTXM), bla(CMY), bla(VIM), and bla(IMP) genes was confirmed. The DNA sequences upstream and downstream of bla(IMP) genes were determined, revealing that all IMP-encoding genes constituted the first cassette of class 1 integrons, followed by aacA gene cassettes encoding aminoglycoside resistance. Comparison of PFGE profiles showed that only 2 of the isolates were clonal, the other 14 displaying unique profiles. The bla(CTX-M) gene was the most dominant of the extended-spectrum β-lactamase (ESBL) genes, while the bla(TEM) gene was the second-most dominant.

CONCLUSION

The discovery of highly diverse ESBL-producing bacteria and metallo-β-lactamases, particularly bla(IMP), in polluted river water raises alarms with regard to the potential dissemination of antibiotic-resistant bacteria in communities through river environments.

Occurrence of clinical isolates ofKlebsiella pneumoniaeharboring chromosomally mediated and plasmid-mediated CTX-M-15 β-lactamase in a Tunisian hospital

The spread of multidrug-resistant strains of Klebsiella pneumoniae in hospitals is of concern to clinical microbiologists, health care professionals, and physicians because of the impact infections caused by these bacteria have in causing morbidity and mortality. Clinical isolates of K. pneumoniae have been found to show resistance to third-generation cephalosporins as a result of acquiring extended-spectrum β-lactamase-producing genes, such as blaCTX-M. Since little is known about the mechanisms of antibiotic resistance observed in Kasserine hospital, Tunisia, this study was undertaken to investigate the mechanisms by which clinical isolates of K. pneumoniae resist β-lactam antibiotics. Twelve strains of K. pneumoniae were collected from patients admitted to Kasserine hospital; these isolates showed multiresistance phenotypes. Molecular genetics investigations using polymerase chain reaction, S1 digestion, and pulsed-field gel electrophoresisshowed that blaCTX-M-15in association with ISEcp1 is responsible for the resistance of these strains to third-generation cephalosporins. It has been determined that blaCTX-M-15is chromosomally mediated and plasmid mediated, which alarming need for infection control to prevent the outbreak of such a resistance mechanism.

Dyslipidemia in the Greater Tunis population: prevalence and determinants

BACKGROUND

Economic development and socio-demographic changes have led to increased frequency of cardiovascular disease and other chronic diseases in Tunisia.

OBJECTIVES

To assess the prevalence of different types of dyslipidemia and to examine their association with sociodemographic characteristics in the Greater Tunis population.

METHODS

The study included 2712 subjects (1228 men and 1484 women) aged 35-70 years, recruited during the years 2004 and 2005 from the Greater Tunis population. Hypercholesterolemia, hypertriglyceridemia, and low HDL cholesterol were defined according to the National Cholesterol Education Program-Adult Treatment Panel III.

RESULTS

The prevalence of hypercholesterolemia, hypertriglyceridemia, and low HDL cholesterol was 40.8% (34.9% in males and 45.8% in females; p < 0.001), 29.2% (31.1% in males and 27.6% in females; p < 0.05), and 21.2% (32.5% in males and 11.5% in females; p < 0.001), respectively. The prevalence was higher in urban than rural regions. Hypercholesterolemia was more frequent in illiterate women and in men with high education level.

CONCLUSIONS

Dyslipidemias are common in Tunisians, mainly in urban areas, in illiterate women as well as in men with high levels of education. Profound changes of life style and dietary habits of Tunisians are needed to reduce the risk of cardiovascular diseases.

VIM and IMP metallo-β-lactamases and other extended-spectrum β-lactamases in Escherichia coli and Klebsiella pneumoniae from environmental samples in a Tunisian hospital

An extremely drug-resistant Enterobacteriaceae species emerged in Kasserine Hospital, Tunisia between 2009 and 2010 causing a local outbreak. We aimed to characterize extended-spectrum β-lactamase (ESBL) and metallo-β-lactamase (MBL)-producing Enterobacteriaceae from the hospital environment. Swabs were collected from ten different wards from Kasserine Hospital, Tunisia. A total of 46 isolates were cultured onto MacConkey agar supplemented with ceftazidime to select for ESBL-producing Enterobacteriaceae. Identification and susceptibility patterns were performed using Phoenix-automated phenotypic identification criteria. Extended spectrum β-lactamases (ESBLs) were detected using cefepime ESBL E-test. Colony blotting was first used to detect the occurrence of bla(SHV) , bla(CTX-M) , bla(CMY) , bla(IMP) , and bla(VIM) genes. PCR was used to amplify these genes, and the amplicons were sequenced and analyzed. Total DNA was digested with XbaI, and PFGE was used to type the major isolates that produced IMP-1. Among the 46 isolates, 63% were Klebsiella pneumoniae, 13% were Escherichia coli, 8.7% were Proteus mirabilis, 6% were Enterobacter cloaceae, 4.3% were Providencia rettgeri, 2.5% were Serratia marcescens, and 2.5% were Pantoea agglomerans. PCR amplification and DNA sequencing showed that hospital environment isolates produced SHV-125, CTX-M-15, CMY-2 ESBLs, and IMP-1 and VIM-2 MBLs. PFGE typing showed the emergence of IMP-1 MBL-producing K. pneumoniae isolates that were not clonal. In this study, we report the first characterization of IMP-1 and VIM-2 MBL-producing K. pneumoniae and E. coli isolates collected from Kasserine Hospital, Tunisia.

The isomerase Rrd1 mediates rapid loss of the Sgs1 helicase in response to rapamycin

In Saccharomyces cerevisiae , rapamycin exposure inhibits the target of rapamycin (TOR) signaling pathway, causing a profound alteration in the transcription pattern of many genes, including those involved in ribosome biogenesis and nutritional changes. Deletion of the RRD1 gene encoding a peptidyl prolyl isomerase resulted in mutants that are resistant to rapamycin. These rrd1Δ mutants are unable to efficiently downregulate genes such as ribosomal protein genes, or to upregulate genes involved in diauxic shift. It is believed that the isomerase function of Rrd1 plays a role in changing the transcriptional profile upon rapamycin exposure. Herein, we set out to search for genes that when deleted in the rrd1Δ mutant would suppress the rapamycin-resistant phenotype. The analysis revealed that deletion of the SGS1 gene in the rrd1Δ mutant partially suppresses the rapamycin-resistant phenotype of the single rrd1Δ mutant. SGS1 encodes a helicase that functions in many biological processes, including transcriptional regulation. We further show, and for the first time, that Sgs1 is rapidly lost in the parent cells in response to rapamycin, but not by other agents. Interestingly, Sgs1 reduction was completely blocked in the rrd1Δ mutant, suggesting that Rrd1 is required to mediate this process. Genes such as PUT4 and HSP42, known to be upregulated in the parent in response to rapamycin, were not induced in the rrd1Δ mutant if the SGS1 gene was deleted. Since Sgs1 plays a role in transcriptional regulation, we propose that it acts as a repressor of a subset of rapamycin responsive genes. Thus, the observed Rrd1-dependent reduction in Sgs1 level may promote expression of specific classes of genes in response to rapamycin.

Evolution of β-lactams resistance in Gram-negative bacteria in Tunisia

Antimicrobial resistance is a major health problem worldwide, but marked variations in the resistance profiles of bacterial pathogens are found between countries and in different patient settings. In Tunisia, the strikingly high prevalence of resistance of bacteria to penicillins and cephalorosporins drugs including fourth generation in clinical isolates of Gram negative bacteria has been reported. During 30 years, the emerging problem of extended-spectrum β-lactamase-producing Escherichia coli and Klebsiella pneumoniae isolates is substantial, and some unique enzymes have been found. Recently, evidence that Gram-negative bacteria are resistant to nearly all available antimicrobial agents, including carbapenems, have emerged.

Adiponectin expression and metabolic markers in obesity and Type 2 diabetes

BACKGROUND

Adiponectin has emerged over the last decade as a key adipokine linking obesity, insulin resistance, and Type 2 diabetes. However, the molecular mechanisms controlling adiponectin expression in adipose tissue are not fully elucidated. Furthermore, increasing evidence indicates that peroxisome proliferator-activated receptor- γ (PPAR-γ) plays an important, and beneficial, role in modulating adiponectin expression.

AIM

The aim of the present study was to assess the separate role of obesity and Type 2 diabetes in the relationship between endogenous PPAR-γ signaling and adiponectin expression in subcutaneous adipose tissue.

SUBJECTS AND METHODS

Enzyme-linked immuno sor bent assay and real time quantitative PCR analysis were carried out in overweight, obese, and/or diabetic Tunisian patients who underwent an abdominal surgery.

RESULTS

These results collectively indicate that circulating levels of adiponectin were decreased in all overweight, obese, and/or diabetic (p<0.001). However, the subcutaneous mRNA expression of adiponectin was reduced only in diabetics (p<0.01) but presents some discrepancies in obese individuals. Moreover, mRNA levels of adiponectin were positively correlated with levels of mRNA encoding PPARγ and its heterodimeric partner retinoid X receptor-α (RXR-α), in both obese and diabetic patients.

CONCLUSION

Our study on Tunisian patients shows impaired regulation of circulating and mRNA adiponectin levels dependent of metabolic disorders in obesity and Type 2 diabetes. The data suggest that subcutaneous adipose tissue may play an important role in modulating adiponectin expression in diabetes and obesity. Moreover, adiponectin mRNA could be potentially regulated by endogenous PPARγ/RXRα-dependent pathways.

3020insC insertion in NOD2/CARD15 gene, a prevalent variant associated with anti-Saccharomyces cerevisiae antibodies and ileal location of Crohn's disease in Tunisian population

OBJECTIVE

Our aim is to investigate the relation between CARD15 3020insC mutation, anti-Saccharomyces cerevisiae antibodies (ASCA) and disease phenotype, in Tunisian inflammatory bowel disease (IBD) patients.

MATERIALS

A hundred Tunisian patients with IBD (75 Crohn's disease CD and 25 ulcerative colitis UC) and 60 matched healthy controls were studied.

METHODS

CARD15 mutation was analysed by using an allele-specific polymerase chain reaction and sequencing. Assessment of ASCA in serum was performed by ELISA.

RESULTS

The frequency of the mutation was significantly higher in Crohn's disease than in control (p = 0,0005; OR = 20.45; CI 95% = 2.86-413.85) and did not differ statistically in UC group (p = 0, 05) from control. ASCAs were present in 60% of CD and 20, 8% of UC.

CONCLUSION

This study suggests that in northern Tunisian population, 3020insC mutation in NOD2/CARD15 gene is a prevalent mutation leading to the typical Crohn's disease including ileal location, stricturing and penetrating clinical types and ASCA expression.

Interleukin 10 promoter region polymorphisms in inflammatory bowel disease in Tunisian population

OBJECTIVE

To test whether IL-10 promoter region polymorphisms are associated with susceptibility to inflammatory bowel disease, we examined the contribution of interleukin- 10 (IL-10) gene polymorphisms to Crohn's disease (CD) and Ulcerative colitis disease (UC) occurrence and also to CD phenotype. MATERIELS AND METHODS: SNPs at positions -627 (C > A) and -1117 (G > A) in the IL-10 promoter were determined in a sample of 105 Tunisian patients with IBD (75 CD and 30 UC) and 90 matched healthy controls.

RESULTS

The 627 CA genotype is associated with ileal location (p = 0.015) and with stricturing (p = 510-3) and penetrating (p = 310-3) presentation of CD. An additive effect between IL10 variants and CARD15 3020 insC mutation (p = 0,006) on severe forms of CD was shown.

CONCLUSIONS

In Tunisian population, the 3020insC insertion in NOD2/CARD15 gene is a marker of susceptibility to CD, while the A allele at position -627 in the IL-10 promoter increases the risk of CD ileal location and severe disease presentation. A genetic epistasis between IL-10 gene polymorphisms and CARD15/NOD2 gene mutation was suggested.

A study of Gm allotypes and immunoglobulin heavy gamma IGHG genes in Berbers, Arabs and sub-Saharan Africans from Jerba Island, Tunisia

The Gm polymorphism of human IgG immunoglobulins was investigated in three different ethnic groups--Arabs, Berbers and 'dark-skinned people'--on Jerba Island, Tunisia. The genetic relationships among these groups and several populations from North Africa, sub-Saharan Africa, west Asia and Europe were analysed by principal coordinate analysis, Fst significance testing, and analysis of molecular variance based on haplotype frequencies. The results revealed a non-significant genetic differentiation between Arabs and Berbers from Jerba. However, the Jerbian population of sub-Saharan African origin was close to Ethiopians. Gene flow among the three Jerbian populations, as well as an East African origin of the dark-skinned individuals, is proposed to account for the observed genetic pattern. However, the genetic diversity observed among the different Tunisian populations did not show any significant correlation with either geographic or linguistic differentiation. A preliminary analysis of the restriction fragment length polymorphism of the IGHG genes in Arabs and Berbers from Jerba confirmed the close genetic relationship between the two populations. However, it also indicated a lower level of genetic diversity in the Berbers, which may be explained by more rapid genetic drift due to longer isolation on the island.

Allotypy of the rabbit kappa 2 light chain: evidence that the kappa 2 isotype is expressed by all members of the rabbit species

The rabbit kappa 2 light chain subtype was described after isolation of the Basilea mutant strain, which does not express the kappa 1 subtype; antibodies raised in domestic rabbits against the Basilea kappa 2 chain recognized antigenic determinants present in Basilea strain rabbits and in some wild Oryctolagus cuniculus individuals. Some authors have proposed that the kappa 2 isotype is expressed in some individuals and is silent in others. The results presented here provide immunochemical and genetic evidence that the kappa 2 isotype presents at least two allotypic forms, bas 1 (equivalent to bas+) and bas 2 (equivalent to the so-called bas-), which are expressed in low levels in all members of the rabbit species. In addition, preliminary data on the expression of the bas 2 allotype in some hares (Lepus capensis) are reported. On the basis of these results, the rules guiding the selection of kappa 1 and kappa 2 isotypic light chain expression in this species may now be approached.

Allotypy of the rabbit kappa 2 light chain: evidence that the kappa 2 isotype is expressed by all members of the rabbit species

The rabbit kappa 2 light chain subtype was described after isolation of the Basilea mutant strain, which does not express the kappa 1 subtype; antibodies raised in domestic rabbits against the Basilea kappa 2 chain recognized antigenic determinants present in Basilea strain rabbits and in some wild Oryctolagus cuniculus individuals. Some authors have proposed that the kappa 2 isotype is expressed in some individuals and is silent in others. The results presented here provide immunochemical and genetic evidence that the kappa 2 isotype presents at least two allotypic forms, bas 1 (equivalent to bas+) and bas 2 (equivalent to the so-called bas-), which are expressed in low levels in all members of the rabbit species. In addition, preliminary data on the expression of the bas 2 allotype in some hares (Lepus capensis) are reported. On the basis of these results, the rules guiding the selection of kappa 1 and kappa 2 isotypic light chain expression in this species may now be approached.