CHROMOSOME PAIRING, FERTILITY, AND CROSSING BEHAVIOR OF HAPLOIDS OF TETRAPLOID ALFALFA, MEDICAGO SATIV A L.

1971 ◽  
Vol 13 (2) ◽  
pp. 195-202 ◽  
Author(s):  
E. T. Bingham ◽  
C. B. Gillies
Keyword(s):  
Unreduced Gametes ◽  
Female Fertility ◽  
Normal Male ◽  
Normal Female ◽  
Male Sterile ◽  
Stainable Pollen ◽  
Tetraploid Level ◽  
Tetraploid Progeny ◽  
High Degree

Chromosomes paired mainly as bivalents at metaphase in 15 haploids (2n=2x=16) from 10 unrelated stocks of cultivated alfalfa (2n=4x=32). The apparent high degree of chromosome homology and hence autopolyploid chromosome behavior exhibited by the comparatively large sample agreed with that previously reported in independent studies of three other 2x haploids. No gross structural rearrangements of the chromosomes were detected. Haploids produced as much as 50% stainable pollen, but it was only 1-2% germinable in vitro, and they were all effectively male sterile, even when derived from normal male fertile stocks. Two haploids had normal female fertility, whereas forty-eight others were reduced in female fertility in varying degrees. Only four were completely sterile. Since meiosis was normal, the reduction in fertility was due to factors operating postmeiotically. Haploids used as seed parents produced mostly diploid progeny in crosses with diploid M. sativa and M. falcata, and mostly tetraploid progeny in crosses with tetraploids. A few trisomics, other aneuploids, and a pentaploid were also produced. Haploids and diploids derived from them produced a higher frequency of unreduced female gametes than wild diploids. 2x haploids of alfalfa appear to be useful in new approaches to genetic and breeding research, since large numbers can he obtained, they are crossable with wild and derived diploids, and their germplasm can be transferred back to the tetraploid level by unreduced gametes.

scholarly journals Control of the wax moth Galleria mellonella L. (Lepidoptera: Pyralidae) by the male sterile technique (MST)

2010 ◽  
Vol 62 (2) ◽  
pp. 309-313 ◽  
Author(s):  
Reza Jafari ◽  
Shila Goldasteh ◽  
Shahram Afrogheh
Keyword(s):  
Gamma Rays ◽  
Galleria Mellonella ◽  
Effective Dosage ◽  
Normal Male ◽  
Normal Female ◽  
Male Sterile ◽  
Sterile Technique ◽  
Normal Males ◽  
Release Ratio ◽  
Wax Moth

In this study we examined the control of wax moth using the male sterile technique (MST) with gamma-rays. To determine the safe and effective dosage of gamma-rays capable of sterilizing male pupae of the wax moth, male pupae were exposed to increasing single doses of gamma-rays (250, 300, 350 and 400 Gy). The release ratio of sterile to normal males was also studied in a similar experiment. Treatments included sterile males, normal males and virgin females at the following ratios: 1:1:1, 2:1:1, 3:1:1, 4:1:1 and 5:1:1. Possible parthenogenetic reproduction of this pest was also examined. The results showed that 350 Gy was the most effective dose capable of sterilizing the male pupae of the wax moth. The best release ratio was established at four sterile males, one normal male for each normal female (4:1:1). Also females were incapable of producing offspring without males.

Zp4 is completely dispensable for fertility in female rats†

2021 ◽  
Author(s):  
Ming-Hua Zeng ◽  
Yan Wang ◽  
Hua-Lin Huang ◽  
Ru-Ping Quan ◽  
Jun-Ting Yang ◽  
...  
Keyword(s):  
In Vitro Fertilization ◽  
Periodic Acid ◽  
Female Fertility ◽  
Female Rats ◽  
Normal Female ◽  
Vitro Fertilization ◽  
Rat Strain ◽  
Dna Editing ◽  
Extracellular Glycoproteins

Abstract Zona pellucida (ZP), which is composed of at most four extracellular glycoproteins (ZP1, ZP2, ZP3, and ZP4) in mammals, shelters the oocytes and is vital in female fertility. Several studies have identified the indispensable roles of ZP1–3 in maintaining normal female fertility. However, the understanding of ZP4 is still very poor because only one study on ZP4-associated infertility performed in rabbits has been reported up to date. Here we investigated the function of mammalian Zp4 by creating a knockout (KO) rat strain (Zp4−/− rat) using CRISPR-Cas9 mediated DNA-editing method. The influence of Zp4 KO on ZP morphology and some pivotal processes of reproduction, including oogenesis, ovulation, fertilization and pup production, was studied using periodic acid–Schiff’s staining, superovulation, in vitro fertilization, and natural mating. The ZP morphology in Zp4−/− rats was normal and none of these pivotal processes was affected. This study renewed the knowledge of mammalian Zp4 by suggesting that Zp4 was completely dispensable for female fertility.

Production, morphology, and cytogenetics of intergeneric hybrids of Elymus L. species with Triticum aestivum L. and their backcross derivatives

Genome ◽  
1987 ◽  
Vol 29 (5) ◽  
pp. 689-694 ◽  
Author(s):  
Yang Yen ◽  
Dajun Liu
Keyword(s):  
Triticum Aestivum ◽  
Male Gamete ◽  
Triticum Aestivum L ◽  
Intergeneric Hybrids ◽  
Normal Male ◽  
Male Sterile ◽  
Elymus Canadensis ◽  
Key Words Cytogenetics

Elymus canadensis L. (2n = 28, SSHH), E. dahuricus Turcz. ex Griseb. (2n = 42, SSHH??), and E. cylindricus (Franch.) Honda (2n = 42, SSHH??) were successfully hybridized with Triticum aestivum L. cv. Chinese Spring (2n = 42, AABBDD) by in vivo – in vitro embryo culture. The F1 hybrids were male sterile and morphologically intermediate to their parents. The average numbers of associated chromosome arms per cell were 0.24, 2.04, and 0.65, and the mean arm association frequencies were 0.0086, 0.0486, and 0.0155, respectively. The first backcross derivatives all resulted from fusion of an euploid, hypoploid, or hyperploid unreduced F1 female gamete with a normal male gamete of common wheat. They had average numbers of associated arms per cell of 27.10, 24.36, and 23.84, and average chromosome arm association frequencies of 0.644, 0.580, and 0.568, respectively. First backcross derivatives were male sterile but morphologically, closer to their wheat parents. This study shows that no homologous genomes exist between Elymus and Triticum and that gene transfer between these two genera would be very difficult but not impossible. Key words: cytogenetics, Elymus L., Triticum L., hybrid (intergeneric).

Calcium and the Fc Receptor on Human Platelets

1987 ◽  
Vol 57 (03) ◽  
pp. 298-301
Author(s):  
William F Clark ◽  
Gerald J M Tevaarwerk ◽  
Bruce D Reid ◽  
Suzanne Hall ◽  
Anita Caveney ◽  
...  
Keyword(s):  
Specific Binding ◽  
Normal Subjects ◽  
Human Platelets ◽  
Fc Receptor ◽  
Normal Male ◽  
Scatchard Analysis ◽  
Normal Female ◽  
Apparent Difference ◽  
Binding Data ◽  
Direct Binding

SummaryWe have described the calcium dependence of the IgG Fc receptor (Fc-R) on human platelets by analyzing the direct binding of radiolabelled Fc fragments, monomers and dimers of IgG. Specific binding to platelets was undetectable at 37° C in a calcium-free preparation but readily detected when calcium was restored. Scatchard analysis of the binding data for the calcium-restored platelets permitted calculation of the available Fc-R and the Ka of binding for the different IgG ligands. The mean Ka of binding for 12 normal subjects varied from 107 to 108 L/M, with an equal receptor number measured by Fc fragments and dimers of IgG, but a lesser amount for monomeric IgG. There was no apparent difference in Fc-R number for platelets from 6 normal male versus 6 normal female subjects.At 4° C binding was detectable for dimers and polymers of IgG in a calcium-free preparation and this was markedly increased with recalcification. Thus, our data are consistent with an Fc receptor population on human platelets whose avidity for binding is significantly enhanced in a calcium-restored medium.

DER EINFLUSS VON RESERPIN AUF DIE ANTITHYREOIDALE WIRKUNG VON KALIUMPERCHLORAT

1962 ◽  
Vol 39 (3) ◽  
pp. 423-430
Author(s):  
H. L. Krüskemper ◽  
F. J. Kessler ◽  
E. Steinkrüger
Keyword(s):  
Thyroid Gland ◽  
Male Rats ◽  
Normal Male ◽  
Tissue Respiration ◽  
List Type ◽  
Morphological Alterations ◽  
Hormone Synthesis ◽  
Stimulation Of

ABSTRACT 1. Reserpine does not inhibit the tissue respiration of liver in normal male rats (in vitro). 2. The decrease of tissue respiration of the liver with simultaneous morphological stimulation of the thyroid gland after long administration of reserpine is due to a minute inhibition of the hormone synthesis in the thyroid gland. 3. The morphological alterations of the thyroid in experimental hypothyroidism due to perchlorate can not be prevented with reserpine.

scholarly journals Chromatography-Independent Fractionation and Newly Identified Molecular Features of the Adzuki Bean (Vigna angularis Willd.) β-vignin Protein

2021 ◽  
Vol 22 (6) ◽  
pp. 3018
Author(s):  
Biane Philadelpho ◽  
Victória Souza ◽  
Fabiani Souza ◽  
Johnnie Santos ◽  
Fabiana Batista ◽  
...  
Keyword(s):  
Metal Binding ◽  
Cardiovascular Health ◽  
Binding Capacity ◽  
Biological Activities ◽  
Electrophoretic Analysis ◽  
Adzuki Bean ◽  
Molecular Features ◽  
Health Promoting ◽  
High Degree

Adzuki seed β-vignin, a vicilin-like globulin, has proven to exert various health-promoting biological activities, notably in cardiovascular health. A simple scalable enrichment procedure of this protein for further nutritional and functional studies is crucial. In this study, a simplified chromatography-independent protein fractionation procedure has been optimized and described. The electrophoretic analysis showed a high degree of homogeneity of β-vignin isolate. Furthermore, the molecular features of the purified protein were investigated. The adzuki bean β-vignin was found to have a native size of 146 kDa, and the molecular weight determined was consistent with a trimeric structure. These were identified in two main polypeptide chains (masses of 56–54 kDa) that are glycosylated polypeptides with metal binding capacity, and one minor polypeptide chain with a mass 37 kDa, wherein these features are absent. The in vitro analysis showed a high degree of digestibility of the protein (92%) and potential anti-inflammatory capacity. The results lay the basis not only for further investigation of the health-promoting properties of the adzuki bean β-vignin protein, but also for a possible application as nutraceutical molecule.

scholarly journals The Antibacterial Effects of Resin-Based Dental Sealants: A Systematic Review of In Vitro Studies

Materials ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 413
Author(s):  
Saad Saeed AlShahrani ◽  
Mana’a Saleh AlAbbas ◽  
Isadora Martini Garcia ◽  
Maha Ibrahim AlGhannam ◽  
Muath Abdulrahman AlRuwaili ◽  
...  
Keyword(s):  
Antibacterial Agents ◽  
Data Extraction ◽  
Risk Of Bias ◽  
Dental Sealants ◽  
Medium Risk ◽  
Metabolic Activities ◽  
High Degree ◽  
Phosphate Buffered Saline ◽  
Full Text Screening

This review aimed to assess the antimicrobial effects of different antibacterial agents/compounds incorporated in resin-based dental sealants. Four databases (PubMed, MEDLINE, Web of Science and Scopus) were searched. From the 8052 records retrieved, 275 records were considered eligible for full-text screening. Nineteen studies met the inclusion criteria. Data extraction and quality assessment was performed by two independent reviewers. Six of the nineteen included studies were judged to have low risk of bias, and the rest had medium risk of bias. Compounds and particles such as zinc, tin, Selenium, chitosan, chlorhexidine, fluoride and methyl methacrylate were found to be effective in reducing the colony-forming unit counts, producing inhibition zones, reducing the optical density, reducing the metabolic activities, reducing the lactic acid and polysaccharide production and neutralizing the pH when they are added to the resin-based dental sealants. In addition, some studies showed that the antibacterial effect was not significantly different after 2 weeks, 2 months and 6 months aging in distilled water or phosphate-buffered saline. In conclusion, studies have confirmed the effectiveness of adding antibacterial agents/compounds to dental sealants. However, we should consider that these results are based on laboratory studies with a high degree of heterogeneity.

Myocardial CO2 buffering: role of transmembrane transport of H+ or HCO3-ions

1976 ◽  
Vol 230 (4) ◽  
pp. 1037-1041 ◽  
Author(s):  
DR Strome ◽  
RL Clancy ◽  
NC Gonzalez
Keyword(s):  
Small Volume ◽  
Coronary Circulation ◽  
Myocardial Cell ◽  
Ringer Solution ◽  
Red Cells ◽  
Transmembrane Transport ◽  
High Degree

Isolated rabbit hearts were perfused with rabbit red cells suspended in Ringer solution. A small volume of perfusate was recirculated for 10 min at Pco2 of 33.4 +/- 0.9 or 150.8 +/- 7.5 mmHg. Hypercapnia resulted in an increase in perfusate HCO3- concentration that was smaller than that observed when isolated perfusate was equilibrated in vitro with the same CO2 tensions (delta HCO-3e = 1.6 mM, P less than 0.01). This difference is consistent with a net movement of HCO3- into or H+ out of the mycardial cell, and cannot be accounted for by dilution of HCO3- in the myocardial interstitium. Recirculation of perfusate through the coronary circulation at normal Pco2 for two consecutive 10-min periods was not followed by changes in perfusate HCO3- concentration. A high degree of correlation (r = 0.81) was observed between intracellular HCO-3e concentration and the corresponding delta HCO-3e in individual experiments. The results suggest that transmembrane exchange of H+ or HCO3- is a buffer mechanism for CO2 in the myocardial cell.

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