• Molecules and Cells
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• v.25 no.1
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• pp.20-29
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• 2008

Cytoplasmic male sterility (CMS), one of the most important traits in crop breeding, has been used for commercial seed production by $F_1$ hybrid cultivars of pepper (Capsicum annuum L.). To develop reliable molecular markers for allelic selection of the Restorer-of-fertility (Rf) gene, which is known to be a major determinant of pollen fertility restoration in peppers, a sequence of approximately 10 kb flanking an RAPD fragment closely linked to the Rf locus was obtained by genome walking. A homology search revealed that this sequence contained an LTR retrotransposon and a non-LTR LINE-like retrotransposon. Sequencing of this Rf-linked region to search for polymorphisms between a dominant and recessive allele revealed 98% nucleotide sequence identity between them. A third polymorphic haplotype of the Rf-linked sequence, which has 94-96% nucleotide sequence identity with the two previously isolated haplotypes, was identified among a large number of breeding lines. Utilizing polymorphic sequences in the haplotypes, PCR markers were developed for selection of particular haplotypes and used to examine the distribution of the haplotypes in diverse breeding lines, cultivars, and C. annuum germplasms. Surprisingly, the third haplotype was the predominant type in C. annuum germplasms, while its frequency in $F_1$ hybrid cultivars was relatively low. Meanwhile, analysis of breeding lines whose Rf allele genotypes and male-sterility phenotypes were already known revealed that the third haplotype was mainly present in exotic breeding lines that cause unstable male-sterility when combined with sterile cytoplasms.

• Clinical and Experimental Reproductive Medicine
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• v.39 no.4
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• pp.144-152
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• 2012

Objective: Concerns are growing about the decrease in male reproductive health. Caffeine is one of the popular nutrients that has been implicated as a risk factor for infertility. In the present study, we examined whether in utero and lactational exposure to caffeine affects the reproductive function of the offspring of rats. Methods: Pregnant rats received caffeine via drinking water during gestation (26 and 45 mg/kg) and lactation (25 and 35 mg/kg). Body and reproductive organ weight, seminiferous tubule diameter, germinal epithelium height, sperm parameters, fertility rate, number of implantations, and testosterone level of the offspring were assessed from birth to adulthood. Results: Significant dose-related decreases were observed in the body and reproductive organ weight, seminiferous tubule diameter, and germinal epithelium height of the offspring. Sperm density had declined significantly in offspring of the low-dose and high-dose groups, by 8.81% and 19.97%, respectively, by postnatal day 150. The number of viable fetuses had decreased significantly in females mated with male offspring of the high-dose group at postnatal days 60, 90, 120, and 150. There were also significant reductions in testosterone levels of high-dose group offspring from birth to postnatal day 150. Conclusion: It is concluded that maternal caffeine consumption impairs gonadal development and has long-term adverse effects on the reproductive efficiency of male offspring rats.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.8
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• pp.1118-1126
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• 2010

Male reproduction is influenced by a number of intrinsic and extrinsic factors, including environmental endocrine disruptors. Testosterone is a well recognized intrinsic regulator for development and function of the male reproductive tract, and thus male fertility. The testis and semen of many mammalians contain an unusually high concentration of estrogen. Testosterone is converted into estrogen by the enzymatic action of cytochrome P450 aromatase complex (Cyp19a1). Of the male reproductive tract, the efferent ductules (EDs) possess exceptionally elevated levels of estrogen receptors (ERs), ER${\alpha}$ and ER${\beta}$, indicating that estrogen, in addition to testosterone, would have a functional role in regulation of male reproduction. First, this review has focused on description and summary of what is currently known for functions of estrogen in the EDs. The biosynthetic pathway of estrogen occurring in the testis is briefly covered, following by detailed explanation of the morphology and physiology of EDs. In the next section, the sources and targets of estrogen in the male reproductive tract are highlighted, and possible functional roles of estrogen in the EDs are justified from the aspect of physiology, molecular biology, and morphology in adult animal models. Also, this section covers the importance of estrogen and ERs in maintaining normal function and morphology of the EDs during postnatal development. In the last part of this review, the effects of extrinsic factors, especially environmental endocrine-disruptors, on the EDs is summarized. The intent of this review is to emphasize the importance of estrogen for regulation of physiological function of the EDs, and thus male fertility.

• Korean Journal of Poultry Science
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• v.30 no.2
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• pp.95-99
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• 2003

A total of 112 male and 1208 female Ross broiler breeders (30-wk-old) were used in this study to investigate whether a male to female (M/F) ratio of broiler breeder chickens may influence fertility and hatchability of hatching eggs. There were three treatments, each consisting of four pens with a size of 3.2 m ${\times}$ 6.4 m. Each pen housed approx. 100 females and 10 males to give the M/F ratio as follows: T1, 1/9; T2, 1/11; and T3, 1/13, respectively. The fertility of broiler breeder eggs ranged between 93 to 94％ at 30 wk of age. At 35 wk of age, breeder eggs from T3 tended to be less fertile (P>0.05) than those from T1 and T2. The low fertility observed in T3 at 35 wk of age further reduced to reach a statistical significance at 46 wk of age (P<0.05) when compared to those of T1 and T2. Hatchability of breeder eggs among treatments tended to follow a similar trend as shown in fertility, keeping hatchability of breeder eggs from T3 low when compared to the groups of T1 and T2. Our results indicated that the M/F ratio influenced fertility and consequently hatchability of breeder eggs. Furthermore, our study suggests that either 1/9 or 1/11 M/F ratio, but not 1/13 M/F ratio, seems suitable to sustain reproductive performance of broiler breeders throughout the laying periods.

• 대한생식의학회:학술대회논문집
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• 2007.11a
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• pp.55-59
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• 2007

• Toxicological Research
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• v.8 no.1
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• pp.29-40
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• 1992

The recombinant glycoprotein, LBD-005 (Lucky R & D Center, Biotechnology)stimulates the growth of stem cells and activates the development of the hematopoietic cell in a similar manner to the naturally occurring GM-CSF. This test was conducted to investigate if LBD-005 had any effect on fertility in male and female rats. Sprague-Dawley rats(88 of each sex) bred at KRICT, were dosed subcutaneously, at a volume of 2ml/kg body weight with LBD-005 at 0, 250, 500 or 1, 000mg/kg body weight. The male rats were dosed, from 6 weeks of asge, for 60 days prior to mating.

• Clinical and Experimental Reproductive Medicine
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• v.45 no.2
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• pp.88-93
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• 2018

Objective: The aim of this study was to measure reactive oxygen species (ROS) production and total antioxidant capacity (TAC) in the seminal fluid of the male partners in couples undergoing intrauterine insemination and to evaluate correlations between these values and their semen parameters. Methods: The study was conducted at Vamsam Fertility Center, Coimbatore, India and enrolled 110 male patients from whom semen samples were collected. ROS production was measured by a thiobarbituric acid reactive species assay, and TAC was measured by a 2,2-diphenyl-2-picrylhydrazyl free radical assay. The differences in the TAC and malondialdehyde (MDA) levels between the subfertile and fertile groups were analysed. Correlations between sperm parameters and TAC and MDA levels were statistically analysed, and cutoff values with respect to the controls were determined. All hypothesis tests used were two-tailed, with statistical significance assessed at the level of p< 0.05. Results: A total of 87 subfertile and 23 fertile men were included in the study. The mean MDA level was significantly higher in the subfertile subjects than in the fertile subjects, and the mean antioxidant level was significantly lower in the subfertile subjects than in the fertile subjects. Seminal MDA levels were negatively associated with sperm concentration, motility, and morphology, whereas the opposite was seen with TAC levels. Conclusion: Measurements of seminal TAC and ROS are valuable for predicting semen quality, and hence predicting the outcomes of fertility treatment.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.5
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• pp.343-346
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• 2000

Rye breeding using F$_1$ hybrid began about 30 years ago, when cytoplasmically inherited forms of male sterility (CMS) and corresponding nuclear restorers were detected. It is very important to produce inbred lines for making hybrid lines because of strong self-incompatibility in rye. Among the 456 rye germplasms used in hybrid breeding scheme, 24 lines (5.3%) had the above 60% of self-fertility, and six lines of them were selected for their good agronomic characteristics and were used for subsequent inbreeding program. The average self-fertility of selected six lines was 78.4%, ranging from 72.2 to 99.5%. Genetic analysis for the self-fertility using $F_2$ populations showed that the segregation of self-fertile and sterile plants in F$_2$populations could be fit into 3 to 1 ratio suggesting self-fertility in rye be controlled by one major gene. The four different self-fertile lines, PI237923, 5C11, 5G5 and Florida black, had the same self-fertility gene because their F$_2$ plants showed almost the same self-fertility as their parents and showed no genetic segregation.

• Animal Bioscience
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• v.36 no.3
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• pp.385-403
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• 2023

Male fertility is affected by multiple endogenous stressors, including reactive oxygen species (ROS), which greatly deteriorate the fertility. However, physiological levels of ROS are required by sperm for the proper accomplishment of different cellular functions including proliferation, maturation, capacitation, acrosomal reaction, and fertilization. Excessive ROS production creates an imbalance between ROS production and neutralization resulting in oxidative stress (OS). OS causes male infertility by impairing sperm functions including reduced motility, deoxyribonucleic acid damage, morphological defects, and enhanced apoptosis. Several in-vivo and in-vitro studies have reported improvement in quality-related parameters of sperm following the use of different natural and synthetic antioxidants. In this review, we focus on the causes of OS, ROS production sources, mechanisms responsible for sperm damage, and the role of antioxidants in preserving sperm fertility.

• Clinical and Experimental Reproductive Medicine
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• v.40 no.4
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• pp.174-176
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• 2013

Klinefelter syndrome is the most common genetic form of male hypogonadism, but the phenotype becomes evident only after puberty. It is characterized by infertility, small testes, sparse body and facial hair, increased body weight, gynecomastia, increased LH and FSH, and a low level of testosterone. Early recognition and treatment of Klinefelter syndrome can significantly improve the patient's quality of life and prevent serious consequences. Here, we report an infertile man with a rare variant of Klinefelter syndrome with a 47, XY, i(X)(q10) karyotype.