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1.
Sea slugs are interesting models to study post-copulatory sexual selection in simultaneous hermaphrodites due to the enormous variation of their reproductive systems. However, the knowledge of the functional morphology of their reproductive system is limited to few species, and it is rarely discussed in the context of sexual selection theory. In this study, we investigated the functional morphology of the sperm-containing chambers (i.e., ampulla, seminal receptacle, and bursa copulatrix) of the reproductive system of Okenia polycerelloides (Ortea & Bouchet, 1983), based on light, confocal, and electron microscopy. Although the morphology of the ampulla is similar to other species, indicating that it is a site for autosperm storage, we found some sperm facing the ampullar epithelium, a feature commonly regarded as characteristic of the seminal receptacle of sea slugs. The seminal receptacle of O. polycerelloides showed secretory activity and contained sperm with distribution and orientation suggestive of stratification of allosperm from distinct mating events, a feature that would affect sperm competition. The bursa copulatrix had epithelial cells with secretory and absorptive characteristics, and contained degraded sperm and yolk granules within its lumen. Comparative analyses of the contents of each organ demonstrated that sperm digestion occurs in the bursa copulatrix and affects sperm heads first, changing their morphology from slender and curved to shorter and ellipsoid before complete lysis. Although digestion and absorption of surplus sperm are currently the main hypothesized functions for the bursa copulatrix, its role in cryptic female choice should not be ruled out. The close structural connection between the seminal receptacle and bursa copulatrix, as well as their muscular walls, would enable control over the fate of the sperm received in each mating event, that is, storage or digestion. 相似文献
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Angelo Campanozzi Sonia Avallone Antonio Barbato Roberto Iacone Ornella Russo Gianpaolo De Filippo Giuseppina D’Angelo Licia Pensabene Basilio Malamisura Gaetano Cecere Maria Micillo Ruggiero Francavilla Anna Tetro Giuliano Lombardi Lisa Tonelli Giuseppe Castellucci Luigi Ferraro Rita Di Biase Antonella Lezo Silvia Salvatore Silvia Paoletti Alfonso Siani Daniela Galeone Pasquale Strazzullo MINISAL-GIRCSI Program Study Group 《PloS one》2015,10(4)
Background
Hypertension is the leading cause of death in developed countries and reduction of salt intake is recommended as a key preventive measure.Objective
To assess the dietary sodium and potassium intakes in a national sample of Italian children and adolescents and to examine their relationships with BMI and blood pressure (BP) in the framework of the MINISAL survey, a program supported by the Italian Ministry of Health.Population and Methods
The study population included 1424 healthy subjects (766 boys, 658 girls) aged 6-18 years (mean age: 10.1±2.9) who were consecutively recruited in participating National Health Service centers in 10 Italian regions. Electrolyte intake was estimated from 24 hour urine collections tested for completeness by the concomitant measurement of creatinine content. Anthropometric indices and BP were measured with standardized procedures.Results
The average estimated sodium intake was 129 mmol (7.4 g of salt) per day among boys and 117 mmol (6.7 g of salt) among girls. Ninety-three percent of the boys and 89% of the girls had a consumption higher than the recommended age-specific standard dietary target. The estimated average daily potassium intakes were 39 mmol (1.53 g) and 36 mmol (1.40 g), respectively, over 96% of the boys and 98% of the girls having a potassium intake lower than the recommended adequate intake. The mean sodium/potassium ratio was similar among boys and girls (3.5 and 3.4, respectively) and over 3-fold greater than the desirable level. Sodium intake was directly related to age, body mass and BP in the whole population.Conclusions
The Italian pediatric population is characterized by excessive sodium and deficient potassium intake. These data suggest that future campaigns should focus on children and adolescents as a major target in the framework of a population strategy of cardiovascular prevention. 相似文献5.
Finore Ilaria Kasavi Ceyda Poli Annarita Romano Ida Oner Ebru Toksoy Kirdar Betul Dipasquale Laura Nicolaus Barbara Lama Licia 《World journal of microbiology & biotechnology》2011,27(10):2425-2433
This study reports the purification and biochemical characterization of a raw starch-digesting α-amylase from Geobacillus thermoleovorans subsp. stromboliensis subsp. nov. (strain PizzoT). The molecular weight was estimated to be 58 kDa by SDS–PAGE. The enzyme was highly active over a wide range of pH from
4.0–10.0. The optimum temperature of the enzyme was 70°C. It showed extreme thermostability in the presence of Ca2+, retaining 50% of its initial activity after 90 h at 70°C. The enzyme efficiently hydrolyzed 20% (w/v) of raw starches, concentration
normally used in starch industries. The α-amylase showed an high stability in presence of many organic solvents. In particular
the residual activity was of 73% in presence of 15% (v/v) ethyl alcohol, which corresponds to ethanol yield in yeast fermentation
process. By analyzing its complete amyA gene sequence (1,542 bp), the enzyme was proposed to be a new α-amylase. 相似文献
6.
Analía Álvarez Eduardo G. Virla Licia M. Pera Mario D. Baigorí 《Biotechnology letters》2009,31(12):1899-1903
Twelve Bacillus thuringiensis (Bt) strains, isolated from larvae and soil samples in Argentina, were molecularly and phenotypically characterized and their
insecticidal activities against Spodoptera frugiperda and Peridroma saucia were determined. One isolate—Bt RT—produced more than 93% mortality on first instar larvae of both species, which was higher than that produced by the reference
strain Bt 4D1. Bt RT carried a different cry gene profile than Bt 4D1. Scanning electron microscopy showed the presence of bipyramidal and cuboidal crystals. Phenotypic characterization revealed
lytic enzymes that could contribute to Bt pathogenicity. 相似文献
7.
Annarita Poli Vincenzo Schiano Moriello Enrico Esposito Licia Lama Agata Gambacorta Barbara Nicolaus 《Biotechnology letters》2005,26(21):1635-1638
A haloalkalophilic Halomonas strain CRSS, isolated from salt sediments in Antarctica, produced exocellular polysaccharides (EPS) up to 2.9gg-1 dry cells. Acetate was the most efficient carbon source for EPS production. The composition of media strongly affected the nature of the polymers; a mannan and a xylo-mannan, were obtained when cells were grown on complex media. Acetate was the most efficient carbon source for EPS production and in presence of this substrate, a new polysaccharide, a fructo-glucan, was produced. The EPS fraction was composed by glucose, fructose, glucosamine and galactosamine in relative proportions of 1:0.7:0.3:trace.Revisions requested; Revisions received 6 September 2004 相似文献
8.
Licia Carlson 《The Yale journal of biology and medicine》2013,86(3):303-314
This article examines the ethical issues surrounding the inclusion of people with
intellectual disabilities as research subjects. It explores subject selection,
competence, risk and benefits, and authority through three tensions that emerge
when considering these concepts in the context of the Disability Rights Movement
and critical disability scholarship. These tensions are defined as the double
dangers of inclusion and exclusion; the challenges of defining competence and
risk in terms of individuals vs. groups; and the conflicts that arise when
pursuing the dual goals of amelioration and elimination of disabilities. Though
these tensions are not resolved, they underscore the importance of researchers
engaging with critical disability perspectives in order to navigate these
complex ethical questions. 相似文献
9.
Barbara Nicolaus Maria Cristina Manca Licia Lama Enrico Esposito Agata Gambacorta 《Polar Biology》2001,24(1):1-8
Thermoacidophilic and halotolerant microorganisms from the Antarctic continent were studied for their lipid modulation under
stress growth conditions. Temperature-induced changes in complex lipids and fatty acids of four strains belonging to the genus
Alicyclobacillus involved the relative proportions of different polar lipids and the synthesis of ω-cyclohexyl-acyl chains, which were favoured by high temperatures. Studies were carried out on the lipid composition of four
strains of extremely halotolerant bacteria belonging to the genus Micrococcus grown at different salt concentrations from 0 up to 4.5 M NaCl. The main lipids found were two unidentified glycolipids and
two phospholipids: 1,2 diacylglycero-3-phosphoryl-glycerol (PG) and cardiolipin (DPG). Among the strains analysed, the lipids
of the Micrococcus strain Erebus were shown to be strongly influenced by salt concentrations, in that DPG and one glycolipid were absent at
a low salt molarity while, under these conditions, PG was the main lipid found. The predominant fatty acids in all halotolerant
strains were of the anteiso type; growth under increasing salinity gave rise to an increase in long chain fatty acids and of straight chain fatty acids,
while a decrease in iso fatty acids occurred.
Accepted: 20 May 2000 相似文献
10.
Licia Colli Stéphane Joost Riccardo Negrini Letizia Nicoloso Paola Crepaldi Paolo Ajmone-Marsan the ECONOGENE Consortium 《PloS one》2014,9(1)