CD45 Isoform Profile Identifies Natural Killer (NK) Subsets with Differential Activity

The leucocyte-specific phosphatase CD45 is present in two main isoforms: the large CD45RA and the short CD45RO. We have recently shown that distinctive expression of these isoforms distinguishes natural killer (NK) populations. For example, co-expression of both isoforms identifies in vivo the anti tumor NK cells in hematological cancer patients. Here we show that low CD45 expression associates with less mature, CD56^bright, NK cells. Most NK cells in healthy human donors are CD45RA⁺CD45RO^-. The CD45RA^-RO⁺ phenotype, CD45RO cells, is extremely uncommon in B or NK cells, in contrast to T cells. However, healthy donors possess CD45RA^dimRO^- (CD45RA^dim cells), which show immature markers and are largely expanded in hematopoietic stem cell transplant patients. Blood borne cancer patients also have more CD45RA^dim cells that carry several features of immature NK cells. However, and in opposition to their association to NK cell progenitors, they do not proliferate and show low expression of the transferrin receptor protein 1/CD71, suggesting low metabolic activity. Moreover, CD45RA^dim cells properly respond to in vitro encounter with target cells by degranulating or gaining CD69 expression. In summary, they are quiescent NK cells, with low metabolic status that can, however, respond after encounter with target cells.     

Bacterial pollution of the littoral waters of the north of Tunisia (Tabarka and Bizerte regions) and of Lake Bizerte

The inshore areas of Tabarka and Bizerte are not submitted to the bacterian pollution. The "Old Port" of Bizerte is mainly contaminated all the year round and sometimes polluted the neighbouring urban beach. The lagoon of Bizerte presents any bacterian pollution and could be adapted to the conchyliculture and to the stabulation of Bivalves, with before some important precautions.     

Essential Oil Variation among Natural Populations of Lavandula multifida L. (Lamiaceae)

Volatiles from twelve wild Tunisian populations of Lavandula multifida L. growing in different bioclimatic zones were assessed by GC (RI) and GC/MS. Thirty‐six constituents, representing 83.48% of the total oil were identified. The major components at the species level were carvacrol (31.81%), β‐bisabolene (14.89%), and acrylic acid dodecyl ester (11.43%). These volatiles, together with α‐pinene, were also the main compounds discriminating the populations. According to these dominant compounds, one chemotype was revealed, a carvacrol/β‐bisabolene/acrylic acid dodecyl ester chemotype. However, a significant variation among the populations was observed for the majority of the constituents. A high chemical‐population structure, estimated both by principal component analysis (PCA) and unweighted pair group method with averaging (UPGMA) cluster analysis based on Euclidean distances, was observed. Both methods allowed separation of the populations in three groups defined rather by minor than by major compounds. The population groups were not strictly concordant with their bioclimatic or geographic location. Conservation strategies should concern all populations, because of their low size and their high level of destruction. Populations exhibiting particular compounds other than the major ones should be protected first.     

Analysis of 17β-hydroxysteroid dehydrogenase types 5, 7, and 12 genetic sequence variants in breast cancer cases from French Canadian Families with high risk of breast and ovarian cancer

A family history and estrogen exposure are well-known risk factors for breast cancer. Members of the 17β-hydroxysteroid dehydrogenase family are responsible for important steps in the metabolism of androgens and estrogens in peripheral tissues, including the mammary gland. The crucial biological function of 17β-HSDs renders these genes good candidates for being involved in breast cancer etiology. This study screened for mutations in HSD17B7 and HSD17B12 genes, which encode enzymes involved in estradiol biosynthesis and in AKR1C3, which codes for 17β-HSD type 5 enzyme involved in androgen and progesterone metabolism, to assess whether high penetrance allelic variants in these genes could be involved in breast cancer susceptibility. Mutation screening of 50 breast cancer cases from non-BRCA1/2 high-risk French Canadian families failed to identify germline likely high-risk mutations in HSD17B7, HSD17B12 and AKR1C3 genes. However, 107 sequence variants were identified, including seven missense variants. Assessment of the impact of missense variants on enzymatic activity of the corresponding enzymes revealed no difference in catalytic properties between variants of 17β-HSD types 7 and 12 and wild-type enzymes, while variants p.Glu77Gly and p.Lys183Arg in 17β-HSD type 5 showed a slightly decreased activity. Finally, a haplotype-based approach was used to determine tagging SNPs providing valuable information for studies investigating associations of common variants in these genes with breast cancer risk.     

IGL-1 solution reduces endoplasmic reticulum stress and apoptosis in rat liver transplantation

Injury due to cold ischemia reperfusion (I/R) is a major cause of primary graft non-function following liver transplantation. We postulated that I/R-induced cellular damage during liver transplantation might affect the secretory pathway, particularly at the endoplasmic reticulum (ER). We examined the involvement of ER stress in organ preservation, and compared cold storage in University of Wisconsin (UW) solution and in Institute Georges Lopez-1 (IGL-1) solution. In one group of rats, livers were preserved in UW solution for 8 h at 4 °C, and then orthotopic liver transplantation was performed according to Kamada''s cuff technique. In another group, livers were preserved in IGL-1 solution. The effect of each preservation solution on the induction of ER stress, hepatic injury, mitochondrial damage and cell death was evaluated. As expected, we found increased ER stress after liver transplantation. IGL-1 solution significantly attenuated ER damage by reducing the activation of three pathways of unfolded protein response and their effector molecules caspase-12, C/EBP homologous protein-10, X-box-binding protein 1, tumor necrosis factor-associated factor 2 and eukaryotic translation initiation factor 2. This attenuation of ER stress was associated with a reduction in hepatic injury and cell death. Our results show that IGL-1 solution may be a useful means to circumvent excessive ER stress reactions associated with liver transplantation, and may optimize graft quality.     

Polyphenols,flavonoids, antioxidant activity in leaves and flowers of Tunisian Globularia alypum L. (Globulariaceae)

Leaves and flowers from Tunisian Globularia alypum were assessed for their phenolic and flavonoid contents and antioxidant activity. Phenolic (15.5–22.30 mg GAE g^?1 DW) and flavonoid (3.63–4.72 mg RE g^?1 DW) contents varied according to plant part. Globularia alypum leaves exhibited the highest phenol and flavonoid contents, and displayed the highest antioxidant activity, based on radical‐scavenging activity (295 μmol TEAC g^?1 DW) and ferric reducing power (24.27 mmol Fe2+/l). The obtained results demonstrated that some of the isolated compounds play an important role for the antioxidant activity of G. alypum and give a scientific basis to the use of this plant in traditional medicine. The methanolic extract of G. alypum could be considered as a source of potential antioxidants and will promote the reasonable usage of this plant in food technology and processing as well as for medical use.     

Analyse du statut spermatique, érectile et hormonal chez des patients hémodialysés

Introduction

Our work was to establish the hormonal, semen and erectile profile among haemodialysed patients and to seek the impact of hormonal disturbances on erectile function and semen parameters.

Patients and methods

We conducted a cross-sectional study in haemodialysed patients in whom a semen, in parallel with hormonal analyses including FSH (follicle stimulating hormone) and testosterone. Erectile function was assessed by the study of the international index of erectile function in its French version (IIEF). Analyses of sex hormones were done by radio immunoassay and semen analyses according to WHO guidelines.

Results

Two patients had a semen analysis and a normal hormone balance; the IIEF was normal in a one patient. Azoospermic patients (16%) showed a hypergonadotrophic eugonadism. Forty percent of the patients had hypospermia without any correlation between hypospermia and hormonal values. One third of patients showed severe oligospermia associated with high levels of FSH in 77% of cases. Sperm motility and morphology were altered in 96% and 50% of the cases respectively. Hormonal analyses showed an elevated FSH (> 8.5 mUI/ml) in 40% of the cases and testosterone was decreased (< 3.2 ng/ml) in 25% of the cases.

Discussion

Semen volume was significantly decreased in patients over 30 years. Erectile function was disturbed in 73% of the patients with a mean IIEF score of 15. Several authors have shown a correlation between gonadal dysfunction and high levels of gonadotropins in men with chronic renal insufficiency, with or without testicular atrophy. In our series, testosterone was normal despite the absence of androgen. Are haemodialysis sessions effective in preserving the endocrine function?

Conclusion

Patients in chronic haemodialysis for a period exceeding one year had a hypergonadotrophic eugonadism and a severe erectile dysfunction. The state of the genital tract was relatively preserved. The duration of haemodialysis did not significantly affect sperm and erectile function. Patients older than 30 years showed a significant decrease in semen volume, which could be a marker to determine the impairment of erectile and reproductive functions.