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11.
Summary Selected morphological and physiological properties of the corpus allatum (CA)-corpus cardiacum (CC) complex from the two-spotted stinkbug, Perillus bioculatus (Hemiptera: Pentatomidae), were studied. The CAs play an important role in insect physiology because of their production of the juvenile hormones (JHs), i.e., key hormones involved in development and reproduction. We found that the P. bioculatus CA-CC complex is present in two distinct morphological forms, the more frequently observed complex containing one “fused” CA between two CCs and the more rarely observed complex having one CA laterally attached to each CC. These complexes were tested for their ability to synthesize JH-like compounds. We found that the primary lipophilic compound synthesized by the CA-CCs migrated differently from JH III (a JH found in numerous insect species) when subjected to thin-layer chromatography. Furthermore, the synthesis of this compound is stimulated by 2E,6E-farnesol, a known precursor for JH III. These data indicate that the P. bioculatus CA-CC product has chemical properties similar to that of other (as of yet unidentified) hemipteran JHs. In addition, we found that the synthesis of this product is sensitive to pH and buffer type; minimally or not affected by the absence of the CC; expressed at similar levels in days 5–30 postemergent adults; and inhibited or decreased in adults reared under low temperature—short day conditions.  相似文献   
12.
Toxoplasma antibodies prevalence was studied in the north of Tunisia where a mild climate prevails. Two groups of individuals were investigated: 857 living in rural area and 564 living in urb town. Sera were analysed by ELISA and indirect immunofluorescence. The overall prevalence was 58.4%. It roses from 24.5% at ten years to 52.1% at 20 years of age. A maximum level, around 70%, was reached by about 30 years. The risk of acute infection after this age seemed low as judging by the proportion of high antibodies titers observed in this group (14.2% before 30 years vs 3.7% after). A significantly higher prevalence was detected in urban residents (67% vs 52.8%). In this group, the rate of seroconversion seems the highest between ten and 20 years of age and the majority of women are infected before reaching childbearing age. In the rural area, the seropositivity is lower between ten-20 years and many women at childbearing age still susceptible to toxoplasmosis. The risk of acute infection seems higher in the youngest ones as showed by the proportion of high antibodies titers observed in the 18-30 age group (9.2%) compared to the one observed after 30 years (1.9%).  相似文献   
13.
This paper presents the results of a cytogenetic analysis in 139 Tunisian patients with de novo acute myeloid leukemia (AML), including 27 children aged 1-15 years and 112 adults. Mean age was 32 (range 1-75) and the M/F ratio was 1.43. Of our patients, 45% had apparently normal karyotypes. Acquired chromosome aberrations were found in 77 (55% ) patients. t(8;21) was identified in 27 patients (19%); t(15;17) in 13 patients (9%); deletion 7q or monosomy 7 in seven patients (5%); +8 in seven patients (5%); abnormal 16 in four patients (3%); 11q23 rearrangements in two patients (2%) and del(5q), in one patient (1%). The remaining 16 patients had miscellaneous clonal abnormalities. Specific translocations associated with the FAB type were found: t(8;21) with AML2 and t(15;17) with AML3. We concluded that our study in a Tunisian population confirmed the relation between some specific abnormalities and the FAB classification. We found a higher incidence for t(8;21) than usually described.  相似文献   
14.
Touir  Ahlem  Boumiza  Soumaya  Nasr  Hela ben  Bchir  Sarra  Tabka  Zouhair  Norel  Xavier  Chahed  Karim 《Biochemical genetics》2021,59(6):1457-1486

The purpose of this study was to determine the impact of six PGHS-2 genetic variants on obesity development and microvascular dysfunction. The study included 305 Tunisian subjects (186 normal weights, 35 overweights and 84 obeses). PCR analyses were used for allelic discrimination between polymorphisms. Prostaglandin (PGE2, PGI2), leptin, and matrix metalloproteinase (MMP1, 2, 3, 9) levels were evaluated by ELISA. Fatty acid composition was performed by gas chromatography–mass spectrometry. Our results revealed that subjects carrying the PGHS-2 306CC (rs5277) and 8473CC (rs5275) genotypes present higher anthropometric values compared to wild-type genotypes (306GG, BMI (Kg/m2): 27.11?±?0.58; WC (cm): 93.09?±?1.58; 306CC, BMI: 33.83?±?2.46; WC: 109.93?±?5.41; 8473TT, BMI: 27.75?±?0.68; WC: 93.96?±?1.75; 8473CC, BMI: 33.72?±?2.2; WC: 117.89?±?2.94). A reduced microvascular reactivity and a higher PGE2 level were also found in individuals with the 306CC and 8473CC genotypes in comparison to 306GG and 8473TT carriers (306GG, Peak Ach-CVC (PU/mmHg): 0.46?±?0.03; PGE2 (pg/ml): 7933.1?±?702; 306CC, Peak Ach-CVC: 0.24?±?0.01; PGE2: 13,380.3?±?966.2; 8473TT, Peak Ach-CVC: 0.48?±?0.05; PGE2: 7086.41?±?700.31; 8473CC, Peak Ach-CVC: 0.23?±?0.01; PGE2: 13,175.7?±?1165.8). Fatty acid analysis showed a significant increase of palmitic acid (PA) (34.2?±?2.09 vs. 16.82%?±?1.76, P?<?0.001), stearic acid (SA) (25.76?±?3.29 vs. 9.05%?±?2.53, P?<?0.001), and linoleic acid (LA) (5.25?±?1.18 vs. 0.5%?±?0.09, P?<?0.001) levels in individuals carrying the PGHS-2 306CC genotype when compared to GG genotype individuals. Subjects with the 8473CC genotype showed also a significant increase of PA, SA ,and LA levels when compared to TT genotype carriers (PA: 38.02?±?1.51 vs. 12.65%?±?1.54, P?<?0.001; SA: 32.96?±?1.87 vs. 1.38%?±?0.56, P?<?0.001; LA: 26.84?±?2.09 vs. 3.7%?±?1.54, P?<?0.001). Logistic regression analysis revealed that PGHS-2 306CC and 8473CC variants are significantly associated with obesity status (OR 6.25, CI (1.8–21.6), P?=?0.004; OR 3.01, CI (1.13–8.52), P?=?0.03, respectively). Haplotypes containing the C306:T8473 (OR 2.91; P?=?0.01) and G306:C8473 (OR 5.25; P?=?0.002) combinations were associated with an enhanced risk for obesity development in the studied population. In conclusion, our results highlight that PGHS-2 306G/C and 8473T/C variants could be useful indicators of obesity development, inflammation, and microvascular dysfunction among Tunisians.

  相似文献   
15.

Objective

To examine the time-of-day and Ramadan fasting (RF) effects on serum apolipoprotein-AI (Apo-AI) and B (Apo-B), lipoprotein particles-a (Lp-a), high-sensitive C-reactive-protein (hs-CRP), and homocysteine (Hcy) during the Yo-Yo intermittent recovery test (YYIRT).

Design

Performance and biochemical measures were completed at two times-of-day (07:00 and 17:00 h), 1-week before RF (BR), the second week of RF (SWR), and the fourth week of RF (ER).

Setting

For each session, subjects performed the YYIRT, and blood samples were taken before and 3-min after the test for biochemical measures.

Participants

Fifteen soccer players.

Main Outcome Measures

Total distance during the YYIRT, core temperature, body composition, dietary intakes, lipid (HDL-C, LDL-C, Apo-AI, B and Lp-a) and inflammatory (hs-CRP and Hcy) profiles.

Results

Performances during the YYIRT were higher in the evening than the morning BR (P < 0.05), but this fluctuation was not observed during RF. Moreover, LDL-C, ApoB, and Lp-a were stable throughout the daytime BR. However, during RF, they decreased at 17:00 h (P < 0.05). Likewise, HDL-C and Apo-AI increased after the exercise and were higher at 17:00 h BR (P < 0.001). Moreover, these parameters increased during RF (P < 0.01). Furthermore, Hcy and hs-CRP increased during the exercise (P < 0.01) with higher evening levels BR. During ER, the diurnal pattern of Hcy was inversed (P < 0.001).

Conclusions

This study concluded that caloric restriction induced by RF seems to ameliorate lipid and inflammatory markers of cardiovascular health during intermittent exercise performed in the evening.  相似文献   
16.
Apolipoprotein A1 (ApoA1) is the major apoprotein constituent of high-density lipoprotein that can play important roles in tumor invasion and metastasis. In the current report, we evaluated the role of the functional ApoA1 polymorphisms (−75 G/A and +83 C/T) as genetic markers for breast cancer susceptibility and prognosis. We used the polymerase chain reaction and restriction enzyme digestion (RFLP-PCR) to characterize the variations of the ApoA1 gene in 295 unrelated Tunisian patients with breast carcinoma and 197 healthy control subjects. No association was found between the +83 C/T genetic variation in ApoA1 gene and the risk of breast cancer occurrence. The presence of the (+83) T allele appeared however to be associated with an increased risk of lymph node metastasis occurrence (OR = 2.94; P = 0.01). Furthermore, a positive association was found between ApoA1 −75 A allele carriers and breast cancer risk (OR = 1.57; P = 0.02). Regarding prognostic indicators, a significant association was found between ApoA1 (−75) A allele carriers and the premenopausal status of breast cancer patients (OR = 1.73; P = 0.03). Additionally, the presence of the −75 A allele was correlated with the oestrogen receptor status among premenopausal women (OR = 2.45; P = 0.02). This is the first report on the studies of ApoA1 single nucleotide polymorphisms (SNPs) in breast carcinomas. Our data suggest that these genetic variations of ApoA1 may represent a marker for the increased risk of breast cancer.  相似文献   
17.
ABSTRACT: Coronary artery disease (CAD) is a multifactorial disease where genetic and environmental factors interact in complex ways to cause the disease. Heat shock protein genes are involved in the progress of CAD. This implies that genetic variants of Hsp70-2 genes might contribute to the development of the disease. Aim of study The aim of this study was to characterize statistical correlation of linkage between lipid profiles, polymorphism PstI site of Hsp70-2 gene and coronary artery diseases. Patients and methods This study was carried out on Tunisian patients with CAD recruited from Hospital of Fattouma Bourguiba of Monastir-Tunisia. Polymerase chain reaction and restriction enzymes were used to determine the genotypic distributions in 252 unrelated patients and 151 healthy control subjects. Further, ApoA-I and ApoB as well as the serum total of cholesterol, HDL, triglyceride, and hs-CRP levels were measured. RESULTS: We showed a decreased level of ApoA-I, whereas the levels of each of ApoB and hs-CRP were increased in patients with CAD compared with control group. In addition our studies of a polymorphic PstI site of Hsp70-2 gene lying in the coding region at position 1267 of the Hsp70-2 gene have revealed that the frequency of P1/P2 heterozygote was 0.484 in patient group compared with control group (0.476, p = 0.046). Whereas, the frequency of the P2/P2 homozygote was 0.190 in patient group and only 0.099 in controls (P = 0.006). These results indicate that the odds ratio of CAD associated with the Hsp70-2 polymorphism is confined the P2/P2 homozygotes (OR 2.498; P = 0.006). CONCLUSION: Taken together, our results indicate that the high frequency of P2/P2 genotype is associated with elevated levels of biochemical parameters (LDL cholesterol, hs-CRP) in Tunisian patient group. The Hsp70-2 polymorphism has susceptibly implication in CAD. Virtual slides The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1118340895703689.  相似文献   
18.
Oxidative stress in semen is essentially due to excessive production of oxygen-reactive species (ORS) essentially derived from leukocytes. DNA oxidation is due to the direct action of ORS which produce several adducts the most extensively studied of which is 8-oxo-guanine. Integrity of DNA is essential for the fertility of sperm and is an important subject of research for scientists and clinicians all over the world. Although evaluation of the global integrity of sperm DNA has considerably developed over recent years, few tests are available to document oxidative DNA damage. This study was designed to review the various tests of sperm DNA integrity commonly used in the literature and to present the results of our study on DNA oxidation with 8-oxo-guanine labelling by flow cytometry in infertile men. This study was based on 15 semen samples that were submitted to sperm analysis according to WHO guidelines, with determination of the leukocyte concentration by a cytochemical method revealing peroxidase in cytoplasmic granulations. The DNA oxidation study was performed with 8-oxo-guanine labelling by flow cytometry. Linear regression analysis showed a strong correlation between DNA oxidation and leukocyte count in the semen (p = 0.006, r = 0.7). A leukocyte cut-off of 250,000/ml of semen was associated with a significant increase of DNA oxidation (p = 0.03). 8-oxo-guanine can therefore be considered to be a biological marker of the direct action of oxidative stress on sperm DNA which appears to be susceptible to relatively low levels of ORS produced by leukocytes present at concentrations well below the limit of leukospermia defined by WHO.  相似文献   
19.
20.
Velocity fields have been measured in models simulating arterial stenoses for continuous and revolution flows. A pulsed Doppler velocimeter allows for velocity readings in the entire tube and in the wall area. Streamlines are determined by numerical solving of the system of equations defining the current function. Velocity profiles and streamlines are presented and discussed either for steady or for unsteady flows, with different Reynolds numbers and variable degrees of stenosis. There is, in the wall area, a recirculating zone made of a well-defined rouleau. Its length varies increasingly according to the increasing severity of the stenosis. The stability of axial flow depends on the input profile, the degree of stenosis and the Reynolds number. Plotting streamlines allows to describe accurately the flow; its quantitative aspect offers advantages with respect to conventional visualization mode.  相似文献   
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