Induced change in <Emphasis Type="Italic">Arthrospira</Emphasis> sp. (<Emphasis Type="Italic">Spirulina</Emphasis>) intracellular and extracellular metabolites using multifactor stress combination approach

The interactive effects of light intensity, NaCl, nitrogen, and phosphorus on intracellular biomass content and extracellular polymeric substance production were assessed for Arthrospira sp. (Spirulina) in a two-phase culture process using principal component analysis and central composite face design. Under high light intensity (120 μmol photons m^?2?s^?1) and low NaCl (1 gL^?1), NaNO₃, and K₂HPO₄ (0.5 g L^?1), the carbohydrate content was maximized to 26.61%. Interaction of both K₂HPO₄ (1.6 gL^?1) and NaCl (1.19 gL^?1) with low NaNO₃ (0.5 gL^?1) achieved the maximum content of lipids (15.62%), while high NaCl (40 gL^?1), K₂HPO₄, and NaNO₃ (4.5 gL^?1) enhanced mainly total carotenoids (0.85%). Conversely, under low light intensity of 10 μmol photons m^?2?s^?1 combined with 11.76 gL^?1 of NaCl, 0.5 gL^?1 of NaNO₃, and 2.68 gL^?1 of K₂HPO₄, the phycobiliprotein content reached its highest level (16.09%). The maximum extracellular polymeric substance (EPS) production (0.902 gg^?1?DW) was triggered under moderate light of 57.25 μmol photons m^?2?s^?1 and interaction of high NaCl (40 gL^?1) and K₂HPO₄ (4.5 gL^?1) with low NaNO₃ (0.5 gL^?1). The maximization ratios of intracellular biomass content in terms of carbohydrate, lipid, total carotenoid, phycobiliprotein, and EPS production were 3.55-, 1.73-, 9.55-, 2.92-, and 1.46-fold, respectively, greater than those obtained at optimal growth conditions. This study demonstrated that the multiple stress factors applied to the adopted two-phase culture process could be a promising strategy to produce biomass enriched in various high-value compound.     

The Genus Myrtus L. in Algeria: Composition and Biological Aspects of Essential Oils from M. communis and M. nivellei: A Review

The genus Myrtus L. (Myrtaceae family) comprises two species, Myrtus communis L. (known as common myrtle) growing wild all around the Mediterranean basin and Myrtus nivellei Batt . and Trab . (known as Saharan myrtle), found in central Sahara. Only one country, Algeria, hosts both species, M. communis in the North and M. nivellei in the South. The aim of this review was to collect, summarize, and compare the main results reported relative to the essential oils isolated from aerial parts of both species: botanical aspects, habitat, traditional use, chemical composition, new compounds, antimicrobial activity, antioxidant activity, anti‐inflammatory effect, and insecticidal activity. Both essential oils have potential applications in human health.     

Synthesis and biological evaluation of a series of aromatic bisphosphonates

Geminal bisphosphonates display varied biological activity depending on the nature of the substituents on the central carbon atom. For example, the nitrogenous bisphosphonates zoledronate and risedronate inhibit the enzyme farnesyl diphosphate synthase while digeranyl bisphosphonate has been shown to inhibit the enzyme geranylgeranyl diphosphate synthase. We now have synthesized isoprenoid bisphosphonates where an aromatic ring has been used to replace one of the isoprenoid olefins in an isoprenoid bisphosphonate and investigated the ability of these new compounds to impair protein geranylgeranylation within cells. Several of these new compounds are potent inhibitors of the enzyme geranylgeranyl diphosphate synthase.     

Prévalence de la pyospermie et retentissement sur la qualite du sperme chez les hommes infertiles

There are numerous controverses concerning the relationship between the presence of leukocytes in semen and male infertility. In the aim to determine the impact of pyospermia on sperm quality, we have realised a retrospective study in which we analysed and compared semen parameters and abnormalities frequencies between pyospermic and non pyospermic infertile patients. 833 spermiograms were included in this study. They were done in accord with WHO method. Leucocytes identification was performed by cyto-enzymologic method that reveals myelo-peroxydase in polymorphonuclear granulations. Pyospermia was considered when number of leucocytes was more than one million per millititre of sperm. The non pyospermic group was composed by sperm with leucocytospermia less than 50.000 per millilitre. The prevalence of pyospermia was 5.88%. There was not significative difference of semen parameters (volume, motility, morphology, number of spermatozoa and viability) between pyospermic and non pyospermic groups. In the other hand, no correlation was found between leucospermia and semen parameters. However, oligospermia was significantly more frequent in pyospermic group (40.8%) than in non pyospermic group (20,3%). Inversly, the frequence of teratospermia was significantly higher in non pyospermic group (47.2% vs 34.1%, p<0,05). These results suggest that inflammation and/or infection associated with pyospermia is complicated by reduction of spermatic ducts permeability. Although, the leucocytes would act in removing amorphous gametes by phagocytosis. No relationship was established between pyospermia and infection. In future, a prospective study would be done with exhaustive exploration of pyospermia etiology, with hopes to clarify the true link with infection and autoimmune reaction and to determine the effect of pyospermia on glandular activities in male genital tract and on functional properties of spermatozoa.     

The impact of thyroid activity variations on some oxidizing-stress parameters in rats

The effect of the thyroid activity on the formation of lipid peroxidation and on liver and heart antioxidant enzyme activities was investigated in Wistar rats. Hypothyroidism and hyperthyroidism conditions were induced for five weeks by the administration of 0.05% benzythiouracile (BTU) and L-thyroxine sodium salt (0.0012%), in drinking water, respectively. No significant effect was observed on the rates of both lipid peroxidation and the vitamin E in hepatic and cardiac tissues of hypothyroidism rats compared to the controls, contrary to the hyperthyroidism rats, which expressed a pronounced increase. The increased glutathione peroxidase activity in rats suffering from hyperthyroidism was associated with a fall of the reduced glutathione in the homogenate and a marked increase in the glutathione reductase activity. An increase in superoxide dismutase and catalase activities was also recorded in hyperthyroidism. Our results explain the thyroid activity variation in relation to the lipid peroxidation and the tissular contents of the enzymatic and the non-enzymatic antioxidants. To conclude, our results show the occurrence of a state of oxidizing stress in relation to hyperthyroidism.     

Effects of salicylhydroxamic acid on the proliferation of Atriplex and murine neuroblastoma cells, and on Drosophila egg laying and development

Salicylhydroxamic acid (SHAM) inhibits the proliferation of cultured plant (Atriplex halimus) and murine neuroblastoma cells with IC50 of 90 and 250 microM, respectively. After 2 h of application, SHAM induces an acceleration of the neuroblastoma cell cycle from G1/S to G2 phases and, after 6 h, it induces an accumulation of the cells in S phase and a cell swelling. Up to 300 microM, SHAM is not cytotoxic and does not induce electrophysiological differentiation of neuroblastoma cells. When Drosophila females are grown in media containing 0.6-1.25 mM SHAM, the rate and number of laid eggs are increased. Furthermore, SHAM stimulates the different development stages from embryo to adult. A general interpretation of the effects of SHAM on cell proliferation and differentiation is proposed.     

Intra-individual heterostyly in Atriplex halimus L. (Amaranthaceae)

Classically, the Atriplex halimus L. female flower is perianthless, has two bracteoles, one ovary and one style. Considering bracteoles, one can distinguish, among the representatives of two Tunisian populations, three phenotypes of female flowers, each of them being distributed in three types according to the style length. Male flowers produce three types of pollen. This is the only known example of intra-individual heterostyly in unisexual flowers. These results question the classical concept of individual. The authors discuss a possible process implying indirectly hybridisation and introgression between A. halimus and A. nummularia.     

Aspects cliniques et biologiques de l’azoospermie chez l’homme infertile en Tunisie

Objective

It is now very important to investigate azoospermia because the introduction of the intracytoplasmic sperm injection technique during the last decade has allowed many infertile men to achieve their dreams of fatherhood. The purpose of this study was to define the characteristics of infertile men with azoospermia, and to analyse the clinical and laboratory features and the causes of infertility in Tunisia. The authors also discuss various aspects that they consider to be very important in the diagnosis of male fertility.

Material and Methods

This retrospective study analysed the parameters of physical examination, laboratory tests, semen analysis, radiographic examinations, testicular biopsy, karyotype and AZF microdeletions.

Results

Based on the results of endocrinological and cytogenetic examinations, the aetiology of azoospermia was considered to be secretory in 43 cases of azoospermia. Physical examination revealed a high percentage of hypotrophic/atrophic testes (43.9%). Serum follicle stimulating hormone levels were high in 58.5% of cases. The overall incidence of chromosomal abnormalities was 31.4%. The most frequent anomaly was Klinefelter syndrome (9 cases). Seven out of 28 patients (25%) with nonobstructive azoospermia had AZF deletions. None of the patients with excretory azoospermia and severe oligospermia had an abnormal karyotype or AZF microdeletions. 48.8% of patients presented a varicocele, 13.9% had cryptorchidism and 13.0% had a history of genital tract infection.

Conclusion

In line with the literature, genetic abmormalities are the main causes of severe forms of impaired spermatogenesis in the Tunisian population.