The mitotic behavior of the epithelium of the uterus at different stages of the sexual cycle in mice

1958 ◽  
Vol 46 (5) ◽  
pp. 1399-1402 ◽  
Author(s):  
O. I. Epifanova
Author(s):  
Т.В. Никитина ◽  
А.А. Кашеварова ◽  
М.М. Гридина ◽  
А.А. Хабарова ◽  
А.Г. Мензоров ◽  
...  

Митотическая нестабильность кольцевых хромосом может приводить к появлению клеточных клонов с различной генетической структурой. В качестве модели нестабильности кольцевых хромосом в митозе мы использовали фибробласты от пациентов с r(8), r(13), r(18) и r(22) и полученные из них индуцированные плюрипотентные стволовые клетки (ИПСК). Линии ИПСК с r(22) имели относительно стабильный кариотип на протяжении десятков (до 60) пассажей и сохраняли неизменную структуру кольцевой хромосомы. Кариотип линий ИПСК с r(8) и r(18) на ранних пассажах стабильный, планируется его изучение на поздних пассажах. Наибольшее разнообразие кариотипа выявлено в линиях ИПСК с r(13), в которых наблюдали различные перестройки и выраженную клеточную гетерогенность. Определение факторов, влияющих на митотическую стабильность кольцевых хромосом, может иметь значение для консультирования пациентов. Mitotic instability of ring chromosomes can lead to the appearance of cell clones with different genetic structure. IPSCs from fibroblasts of patients with r(8), r(13), r(18), and r(22) were used as a model of ring chromosomes mitotic behavior. Karyotypes of iPSC lines with r(8) and r(18) have so far been evaluated only in the early passages, lines with r(22) have maintained a relatively stable karyotype up to 60 passages. The occurrence of rearrangements and cellular heterogeneity was found characteristic for r(13) iPSCs. The determination of factors affecting the ring chromosomes mitotic stability would be beneficial for the patient’s prognosis.


Author(s):  
Г.В. ШИРЯЕВ ◽  
Ю.Г. ТУРЛОВА ◽  
Г.С. НИКИТИН

Изучено влияние кормовой добавки в форме индивидуальных болюсов Метраболь на возможность снижения негативного влияния субклинического кетоза (СКК) и результативность искусственного осеменения высокопродуктивных молочных коров в посттранзитный период. Животные были подобраны по принципу условных аналогов и разделены на 3 группы в зависимости от концентрации β-оксимасляной кислоты в их крови. В I группе (n=18) у коров не было СКК, концентрация кислоты составляла <1,0 ммоль/л, во II группе (n=21) у животных зарегистрирован СКК, концентрация кислоты — 1,0…1,4 ммоль/л. С целью поиска решения по снижению негативного влияния СКК на репродуктивные показатели была сформирована III группа коров, переболевших СКК (n=24) с концентрацией β-оксимасляной кислоты в крови 1,0…1,4 ммоль/л, но с использованием болюсов, применяемых для ускоренного восстановления репродуктивной функции коров после отела. Важной составляющей опыта явилось то, что к моменту гормональной синхронизации у коров всех 3 групп фиксировалось отсутствие СКК (снижение β-оксимасляной кислоты до уровня <1,0 ммоль/л). Для синхронизации полового цикла выбрана схема Пресинх-овсинх. Установлено, что гормональная синхронизация животных, перенесших СКК, в сравнении со здоровыми, не позволяет снизить негативное влияние данного нарушения обмена веществ. Во II группе у животных зафиксированы самые низкие репродуктивные показатели (количество использованных доз; индекс осеменения, сервис-период; время от первого до успешного осеменения; результат первичного осеменения; количество животных, осемененных 3 и более раз). В III группе применение болюсов позволило, в сравнении с животными II группы, не только избежать отрицательного воздействия СКК, но и превзойти по изучаемым параметрам животных из I группы. The effect of the feed additive in the form of individual boluses Metrabol on the possibility of reducing the negative effect of subclinical ketosis (CCK) and the effectiveness of artificial insemination of highly productive dairy cows in the post-transit period was studied. The animals were selected according to the principle of conditional analogs and divided into 3 groups depending on the concentration of β-hydroxybutyric acid in their blood. In group I (n=18), the cows did not have SSC, the acid concentration was <1.0 mmol/L, in group II (n=21), SSC was registered in animals — 1.0...1.4 mmol / L. In order to find a solution to reduce the negative effect of CCB on reproductive indices, a group III of cows was formed who had CCB (n = 24) with a concentration of β-hydroxybutyric acid in their blood of 1.0...1.4 mmol/L, but using boluses, used to accelerate the restoration of the reproductive function of cows after calving. An important component of the experiment was that by the time of hormonal synchronization, cows of all 3 groups had no SSC (decrease in β-hydroxybutyric acid to a level of <1.0 mmol/L). To synchronize the sexual cycle, the Pressinh-ovsinh scheme was chosen. It was found that hormonal synchronization of animals that underwent SSC, in comparison with healthy ones, does not allow reducing the negative effect of this metabolic disorder. In group II, animals had the lowest reproductive indices (number of doses used; insemination index, service period; time from first to successful insemination; result of primary insemination; number of animals inseminated 3 or more times). In group III, the use of boluses made it possible, in comparison with animals of group II, not only to avoid the negative effect of SSC, but also to surpass the animals from group I in terms of the studied parameters.


Genetics ◽  
2001 ◽  
Vol 158 (2) ◽  
pp. 635-641
Author(s):  
Bina J Mehta ◽  
Enrique Cerdá-Olmedo

Abstract Sexual interaction between strains of opposite sex in many fungi of the order Mucorales modifies hyphal morphology and increases the carotene content. The progeny of crosses of Phycomyces blakesleeanus usually include a small proportion of anomalous segregants that show these signs of sexual stimulation without a partner. We have analyzed the genetic constitution of such segregants from crosses that involved a carF mutation for overaccumulation of β-carotene and other markers. The new strains were diploids or partial diploids heterozygous for the sex markers. Diploidy was unknown in this fungus and in the Zygomycetes. Random chromosome losses during the vegetative growth of the diploid led to heterokaryosis in the coenocytic mycelia and eventually to sectors of various tints and mating behavior. The changes in the nuclear composition of the mycelia could be followed by selecting for individual nuclei. The results impose a reinterpretation of the sexual cycle of Phycomyces. Some of the intersexual strains that carried the carF mutation contained 25 mg β-carotene per gram of dry mass and were sufficiently stable for practical use in carotene production.


Genetics ◽  
1998 ◽  
Vol 148 (4) ◽  
pp. 1829-1832 ◽  
Author(s):  
David Francis

Abstract Analysis of Dictyostelium development and cell biology has suffered from the lack of an ordinary genetic system whereby genes can be arranged in new combinations. Genetic exchange between two long ignored strains, A2Cycr and WS205 is here reexamined. Alleles which differ in size or restriction sites between these two strains were found for seven genes. Six of these are in two clusters on chromosome 2. Frequencies of recombinant progeny indicate that the genetic map of the two mating strains is colinear with the physical map recently worked out for the standard nonsexual strain, NC4. The rate of recombination is high, about 0.1% per kilobase in three different regions of chromosome 2. This value is comparable to rates found in yeast, and will permit fine dissection of the genome.


Genetics ◽  
1986 ◽  
Vol 113 (3) ◽  
pp. 601-619
Author(s):  
Karen P VanWinkle-Swift ◽  
Jang-Hee Hahn

ABSTRACT The non-Mendelian erythromycin resistance mutation ery-u1 shows bidirectional uniparental inheritance in crosses between homothallic ery-u1 and ery-u1  + strains of Chlamydomonas monoica. This inheritance pattern supports a general model for homothallism invoking intrastrain differentiation into opposite compatible mating types and, further, suggests that non-Mendelian inheritance is under mating-type (mt) control in C. monoica as in heterothallic species. However, the identification of genes expressed or required by one gametic cell type, but not the other, is essential to verify the existence of a regulatory mating-type locus in C. monoica and to understand its role in cell differentiation and sexual development. By screening for a shift from bidirectional to unidirectional transmission of the non-Mendelian ery-u1 marker, a mutant with an apparent mating-type-limited sexual cycle defect was obtained. The responsible mutation, mtl-1, causes a 1000-fold reduction in zygospore germination in populations homozygous for the mutant allele and, approximately, a 50% reduction in germination for heterozygous (mtl-1/mtl-1  +) zygospores. By next screening for strains unable to yield any viable zygospores in a cross to mtl-1, a second putative mating-type-limited mutant, mtl-2, was obtained. The mtl-2 strain, although self-sterile, mates efficiently with mtl-2  + strains and shows a unidirectional uniparental pattern of inheritance for the ery-u1 cytoplasmic marker, similar to that observed for crosses involving mtl-1. Genetic analysis indicates that mtl-1 and mtl-2 define unique unlinked Mendelian loci and that the sexual cycle defects of reduced germination (mtl-1) or self-sterility (mtl-2) cosegregate with the effect on ery-u1 cytoplasmic gene transmission. By analogy to C. reinhardtii, the mtl-1 and mtl-2 phenotypes can be explained if the expression of these gene loci is limited to the mt  + gametic cell type, or if the wild-type alleles at these loci are required for the normal formation and/or functioning of mt  + gametes only.


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