The effect of gradual increase in salinity on the biomass productivity and biochemical composition of several marine,halotolerant<Emphasis Type="Bold">,</Emphasis> and halophilic microalgae

Open ponds are the preferred cultivation system for large-scale microalgal biomass production. To be more sustainable, commercial scale biomass production should rely on seawater, as freshwater is a limiting resource, especially in places with high irradiance. If seawater is used for both pond fill and evaporative volume makeup, salinity of the growth media will rise over time. It is not possible for any species to achieve optimum growth over the whole saline spectrum (from seawater salinity level up to salt saturation state). In this study, we investigated the effects of gradual salinity increase (between 35 and 233 ppt) on biomass productivity and biochemical composition (lipid and carbohydrate) of six marine, two halotolerant, and a halophilic microalgae. A gradual and slow stepped salinity increase was found to expand the salinity tolerance range of tested species. A gradual reduction in biomass productivity and maximum photochemical efficiency was observed as a consequence of increased salinity in all tested species. Among the marine microalgae, Tetraselmis showed highest biomass productivity (32 mg L^?1 day^?1) with widest salinity tolerance range (35 to 109 ppt). Halotolerant Amphora and Navicula were able to grow from 35 ppt to 129 ppt salinity. Halophilic Dunaliella was the only species capable of growing between 35 and 233 ppt and showed highest lipid content (56.2%) among all tested species. This study showed that it should be possible to maintain high biomass in open outdoor cultivation utilizing seawater by growing Tetraselmis, Amphora, and Dunaliella one after another as salinity increases in the cultivation system.     

Of PCOS Symptoms,Hirsutism Has the Most Significant Impact on the Quality of Life of Iranian Women

Introduction

Polycystic ovary syndrome is a common endocrine disorder affecting women both physically and psychologically and can lead to a poor quality of life compared to their normal counterparts. The aim of the present study was to assess the impact of various clinical features of polycystic ovary syndrome on the health-related quality of life of Iranian women diagnosed with this syndrome.

Materials and Methods

A total of 796 women diagnosed with polycystic ovary syndrome, aged 15–49 years, completed the questionnaires, interviews, and medical assessments required for this study. A reliable and validated Persian version of the health-related quality of life questionnaire for polycystic ovary syndrome patients was used. Linear regression models were used to assess the association between the symptoms of polycystic ovary syndrome and health-related quality of life.

Results

The mean age of participants was 28.02 years. 35.4% of the subjects were classified as overweight or obese. Hirsutism, was reported to have the strongest impact on the patients’ health-related quality of life, followed in descending order by body mass index, irregular menses and infertility. The relative level of hirsutism was directly proportional to decrease in health-related quality of life score (p<0.001).

Conclusions

The results of the study found that hirsutism had the strongest impact on the health-related quality of life measures in Iranian women diagnosed with polycystic ovary syndrome. Health care officials need to evaluate in depth the effect of each clinical feature of polycystic ovary syndrome separately and design management strategies, keeping in mind the psychological and physical manifestations.     

Effects of 2,4-D removal on the synthesis of specific proteins by Catharanthus roseus cell cultures

Total and neosynthesized proteins of periwinkle cell suspensions (Catharanthus roseus) were first investigated in cells grown in a 2,4-D-containing medium. Analysis of total (silver-stained) proteins by two-dimensional gel electrophoresis revealed that the levels of seventeen polypeptides were altered during the growth cycle of the cells. Analysis of in vivo [³⁵S]-methionine labeled polypeptides revealed differences in the synthesis of at least 35 polypeptides. Three polypeptides with molecular masses of 30, 35 and 39 kDa appeared to be specific markers of the early stationary phase. In a second sequence of experiments, cells were grown in a 2,4-D-free medium. Alterations in protein synthesis were observed: several polypeptides were expressed earlier in the 2,4-D-starved cells than in control cells; the synthesis of at least two specific polypeptides was increased in cells grown in 2,4-D-free medium, whereas the synthesis of three other polypeptides (molecular masses 33, 34 and 52.5 kDa) was switched on in these cells. As previous studies showed that 2,4-D depletion increased the alkaloid production in C. roseus cells, the present results may suggest that these polypeptides are implicated in the regulation of the alkaloid pathway.     

Cloning and expression of an alpha-amylase gene from Streptomyces thermoviolaceus CUB74 in Escherichia coli JM107 and S. lividans TK24

A gene coding for a thermostable extracellular alpha-amylase, carried by a 5.7 kb BamHI chromosomal DNA fragment isolated from Streptomyces thermoviolaceus strain CUB74, was cloned into Escherichia coli JM107 using, as a cloning vector, the high-copy-number plasmid pUC8. E. coli containing a recombinant plasmid pQR300 expressed the amylase gene and exported the enzyme into the periplasmic space and the culture medium. The amylase protein expressed by E. coli had the same molecular mass (50 kDa) as that expressed by the Streptomyces parent strain, which suggests that the enzyme is processed similarly by both strains. The amylase gene was also cloned into Streptomyces lividans TK24 using pIJ702 as vector. The enzyme was stable at 70 degrees C when CaCl2 was present.     

Introgressive hybridization and morphological transgression in the contact zone between two Mediterranean Solea species

Hybrid zones provide natural experiments where new combinations of genotypes and phenotypes are produced. Studying the reshuffling of genotypes and remodeling of phenotypes in these zones is of particular interest to document the building of reproductive isolation and the possible emergence of transgressive phenotypes that can be a source of evolutionary novelties. Here, we specifically investigate the morphological variation patterns associated with introgressive hybridization between two species of sole, Solea senegalensis and Solea aegyptiaca. The relationship between genetic composition at nuclear loci and individual body shape variation was studied in four populations sampled across the hybrid zone located in northern Tunisia. A strong correlation between genetic and phenotypic variation was observed among all individuals but not within populations, including the two most admixed ones. Morphological convergence between parental species was observed close to the contact zone. Nevertheless, the samples taken closest to the hybrid zone also displayed deviant segregation of genotypes and phenotypes, as well as transgressive phenotypes. In these samples, deviant body shape variation could be partly attributed to a reduced condition index, and the distorted genetic composition was most likely due to missing allelic combinations. These results were interpreted as an indication of hybrid breakdown, which likely contributes to postmating reproductive isolation between the two species.     

QTL for relative water content in field-grown barley and their stability across Mediterranean environments

A quantitative genetics approach was developed to identify the genomic regions that control relative water content (RWC) in field-grown barley. The trait was previously demonstrated to be a relevant screening tool of drought-tolerance in cereals, as well as a good indicator of plant water-status. The trait was measured at the heading stage on flag leaves recorded from 167 recombinant inbred lines grown in several Mediterranean sites (Montpellier, France; Meknès, Morocco; Le Kef, Tunisia). The results obtained confirmed that several genomic regions are implicated in the total phenotypic variation of RWC. A total of nine chromosomal regions were identified. One region situated on the long arm of chromosome 6H contains the most-consistent QTL obtained in the present study. This region was previously identified as controlling RWC, as well as leaf osmotic potential under water stress and osmotic adjustment, from an experiment conducted in growth-chamber conditions with the same genetic background. The confirmation of the role of this region in the genetic control of water and turgor status underlined its interest for breeding purposes in the Mediterranean area. In addition, the presence of several dehydrin loci in the same chromosomal area reinforce its interest for genomics analyses to confirm, or not to confirm, the implication of these genes in the variation of RWC.Communicated by H. F. Linskens     

Subcellular localization of LGN during mitosis: evidence for its cortical localization in mitotic cell culture systems and its requirement for normal cell cycle progression

Mammalian LGN/AGS3 proteins and their Drosophila Pins orthologue are cytoplasmic regulators of G-protein signaling. In Drosophila, Pins localizes to the lateral cortex of polarized epithelial cells and to the apical cortex of neuroblasts where it plays important roles in their asymmetric division. Using overexpression studies in different cell line systems, we demonstrate here that, like Drosophila Pins, LGN can exhibit enriched localization at the cell cortex, depending on the cell cycle and the culture system used. We find that in WISH, PC12, and NRK but not COS cells, LGN is largely directed to the cell cortex during mitosis. Overexpression of truncated protein domains further identified the Galpha-binding C-terminal portion of LGN as a sufficient domain for cortical localization in cell culture. In mitotic COS cells that normally do not exhibit cortical LGN localization, LGN is redirected to the cell cortex upon overexpression of Galpha subunits of heterotrimeric G-proteins. The results also show that the cortical localization of LGN is dependent on microfilaments and that interfering with LGN function in cultured cell lines causes early disruption to cell cycle progression.     

Salmonella identification after incubation in the soil

We have tried to study the fate of Salmonella strains in soil. We have looked at their biochemical modifications during their evolution to dormant state and during their reviviscence. The beta galactosidase which is negative in the parent strain became positive after two weeks of cells starvation in soil. Stressed cells became able to produce acetoin. Some stressed cells did not produce the lysine decarboxylase, which is positive in parent cells. These modifications are reversible and depend on cultural conditions. Incubation of stressed cells in nutrient broth for more than four weeks helped them to reverse to normal forms. Simultaneous search for atypical Salmonella was done in dissect sludge of a domestic wastewater treatment plant and in soil irrigated with treated water. Atypical strains of Salmonella are found. We have seen that, after incubation in nutrient broth for more than four weeks, atypical strains characters evolved generally to their parental characters. All modifications of Salmonella in soil samples can make their identification very difficult and perhaps impossible.     

Influence of smoking on serum and milk of mothers, and their infants' serum insulin-like growth factor-I and insulin-like growth factor binding protein-3 levels

OBJECTIVE: To investigate the serum and milk in active-smoking and nonsmoking mothers, and their infants' insulin-like growth factor-I (IGF-I) and insulin-like growth factor binding protein-3 (IGFBP-3) levels. DESIGN AND SETTING: A cohort study conducted at a tertiary medical center. Subjects: Forty-four mothers (age range: 21-34 years) and their newborns (7 days old) were enrolled in the study. Mothers were interviewed and classified according to their smoking status into one of two groups: the active-smoking mothers (n = 21) and the nonsmoking mothers (n = 23). RESULTS: There was no difference noted in either IGF-I, IGFBP-3 or IGF-I/IGFBP-3 ratios in serum and milk of mothers, and their infants' serum samples according to maternal smoking. CONCLUSION: This study demonstrated that maternal smoking (5-10 cigarettes/day) did not influence the maternal and infant serum levels of IGF-I and IGFBP-3 as well as the breast milk levels of these peptides.