bluuebunny/crossref_metadata_2025_split huggingface dataset:
Biological Characteristics of Fish Germ Cells and their Application to Developmental Biotechnology
Authors: Yoshizaki G , Okutsu T , Morita T , Terasawa M , Yazawa R , Takeuchi Y 
Published: July 2012

ContentWe have revealed several unique characteristics of germ cell development using rainbow trout, including the fact that spermatogonia transplanted into the peritoneal cavity of newly hatched embryos migrate toward recipient gonads, that spermatogonia transplanted into female recipients start oogenesis and produce functional eggs and that diploid germ cells transplanted into triploid trout can complete gametogenesis. By combining these unique features of fish germ cells, we established allogeneic and xenogeneic transplantation systems for spermatogonia in several fish species. Spermatogonia isolated from the mature testes of vasa‐green fluorescent protein (Gfp) transgenic rainbow trout were transplanted into the peritoneal cavity of triploid masu salmon newly hatched embryos. These spermatogonia migrated toward recipient salmon genital ridges with extending pseudopodia and were subsequently incorporated into them. We further confirmed that the donor‐derived spermatogonia resumed gametogenesis and produced sperm and eggs in male and female salmon recipients, respectively. By inseminating the resulting eggs and sperm, we obtained only rainbow trout offspring in the F1 generation, suggesting that the triploid salmon recipients produced functional gametes derived only from donor trout. We further confirmed that this intra‐peritoneal transplantation of germ cells is applicable to several marine fishes, which could be of benefit in the production of bluefin tuna that has a large broodstock (>100 kg) and is difficult to maintain in captivity. Gamete production of bluefin tuna could be more easily achieved by generating a surrogate species, such as mackerel, that can produce tuna gametes.
Seminal Plasma and its Effect on Ruminant Spermatozoa During Processing
Authors: Leahy T , de Graaf SP 
Published: July 2012

ContentsSeminal plasma can both inhibit and stimulate sperm function, making its use as a supportive medium somewhat contradictory. These effects are directed by the multifunctional action of numerous inorganic and organic components, but it is the direct association of seminal plasma proteins with the sperm membrane that is thought to exert the most significant response. In vitro handling of spermatozoa in preparation for artificial insemination may involve washing, dilution, cooling, freezing, re‐warming and sex‐sorting. These processes can alter proteins of the sperm surface and reduce seminal plasma in the sperm environment. This, among other factors, may destabilize the sperm membrane and reduce the fertilizable lifespan of spermatozoa. Such handling‐induced damage may be prevented or reversed through supplementation of seminal plasma, but the effectiveness of this technique differs with species, and the source and subsequent treatment of both spermatozoa and seminal plasma. Seminal plasma appears to act as a protective medium during in vitro processing of ram spermatozoa, but this does not appear to be the case for bull spermatozoa. The reasons for this divergent effect will be discussed with particular emphasis on the influence of the major proteins of ruminant seminal plasma, known as BSP proteins. The biochemical and biophysical properties of these proteins are well documented, and this information has provided greater insight into the signalling pathways of capacitation and the protective action of extender components.
Effects of Surgical Sterilization on Canine and Feline Health and on Society
Authors: Root Kustritz MV 
Published: July 2012

ContentsSurgical sterilization of dogs and cats is a well‐accepted measure for population control in some countries, but is considered unethical as an elective surgery in other countries. This is a review of what is known regarding positive and negative effects of gonadectomy surgery on individual animals and on societal management of unowned dog and cat populations.
Selective Breeding in Fish and Conservation of Genetic Resources for Aquaculture
Authors: Lind CE , Ponzoni RW , Nguyen NH , Khaw HL 
Published: July 2012

ContentTo satisfy increasing demands for fish as food, progress must occur towards greater aquaculture productivity whilst retaining the wild and farmed genetic resources that underpin global fish production. We review the main selection methods that have been developed for genetic improvement in aquaculture, and discuss their virtues and shortcomings. Examples of the application of mass, cohort, within family, and combined between‐family and within‐family selection are given. In addition, we review the manner in which fish genetic resources can be lost at the intra‐specific, species and ecosystem levels and discuss options to best prevent this. We illustrate that fundamental principles of genetic management are common in the implementation of both selective breeding and conservation programmes, and should be emphasized in capacity development efforts. We highlight the value of applied genetics approaches for increasing aquaculture productivity and the conservation of fish genetic resources.
Nutritional Influences on Folliculogenesis
Authors: Hernandez‐Medrano JH , Campbell BK , Webb R 
Published: July 2012

ContentsFolliculogenesis is an intricate process that involves the proliferation and differentiation of both somatic and germ cells. This process depends on complex interactions between systemic factors such as both pituitary gonadotrophins and metabolic hormones and/or local factors produced by the ovarian somatic and germ cells, such as the IGF system and TGF‐β superfamily members. In domestic ruminants, follicular development begins during foetal life with formation of primordial follicles from the association of germ cells and pre‐granulosa cells. After follicular formation, folliculogenesis begins with a primordial follicle progressing into more developed stages (i.e. primary, secondary, pre‐antral and antral) in a continuous, progressive process to either ovulation or, as in most cases, to atresia. Even early stages of follicular formation and subsequent development are influenced by both internal (e.g. genotype) and/or external environmental (e.g. nutrition and season) factors. Among these external factors, nutrition is one of the most important affecting reproductive function, and this is the focus of this review, because other reviews in this issue discuss other environmental factors. A number of studies have now shown that nutrition can have both positive and negative effects on follicular growth, oestrous activity, oocyte quality, blastocyst development and pregnancy outcome. Therefore, understanding the intricate processes involved during folliculogenesis and the ways in which factors, such as nutrition, affect them is leading to new opportunities to improve pregnancy rates by influencing follicle development and oocyte quality. This review will focus on follicular development from foetal to adult stages and the influences that nutrition has during some of these developmental stages.
Follicle Selection in the Avian Ovary
Authors: Johnson PA 
Published: July 2012

ContentsFollicle development in the highly efficient laying hen is characterized by a well‐organized follicular hierarchy. This is not the case in other chickens such as the broiler breeder hen that has excessive follicle development and lower reproductive efficiency. Although management practices can optimize egg production in less productive breeds of chickens, the factors that contribute to this difference are not known. Interactions between the oocyte and surrounding somatic cells are believed to be involved in promoting follicle selection. Anti‐Müllerian hormone (AMH) has been shown to have a role in regulating rate of follicle development in mammals. In hens, the expression of AMH is restricted to the growing population of follicles and, similar to mammals, is markedly decreased at around the time of follicle selection. The oocyte factors, growth and differentiation factor 9 (GDF9) and bone morphogenetic protein 15 (BMP15), have been identified in the hen, and their expression pattern has been characterized. Anti‐Müllerian hormone expression in hens is decreased by a protein factor from the oocyte (not GDF9) and is also decreased by vitamin D. Associated with the decrease in AMH expression by vitamin D, follicle‐stimulating hormone receptor mRNA is increased. These data suggest that information about AMH regulation may enhance our understanding of follicle selection, particularly in birds with aberrant follicle development.
Should Weaning be the Start of the Reproductive Cycle in Hyper‐prolific Sows? A Physiological View
Authors: Kemp B , Soede NM 
Published: July 2012

ContentsNormally, sows are in anoestrus during lactation and start their new cycle at the day of weaning. Modern hybrid primiparous sows that suckle large numbers of piglets may lose substantial amounts of body reserves during lactation. This compromises follicle development during lactation. As modern sows have short weaning‐to‐oestrus intervals, these compromised follicles are recruited for ovulation directly after weaning, resulting in lower ovulation rates and lower embryo survival. Postponing or skipping first oestrus after weaning in primiparous sows may help to limit the negative consequences of lactation on subsequent reproduction. Multiparous sows may have very high litter sizes, especially after long lactations as applied in organic sows. These high litter sizes compromise piglet birthweight and survival and subsequent performance. Inducing lactation oestrus in multiparous sows may help to limit litter size and improve piglet survival and performance. This study discusses physiological and reproductive effects of extending the start of a new pregnancy after lactation in primiparous sows and induction of lactation oestrus in multiparous sows. We thereby challenge the view that weaning is an ideal start for the reproductive cycle in modern sows.
Impact of Metal Nanoparticles on Germ Cell Viability and Functionality
Authors: Taylor U , Barchanski A , Kues W , Barcikowski S , Rath D 
Published: July 2012

ContentsMetal nanoparticles play an increasing role in consumer products, biomedical applications and in the work environment. Therefore, the effects of nanomaterials need to be properly understood. This applies especially to their potential reproductive toxicology (nanoreprotoxicity), because any shortcomings in this regard would be reflected into the next generation. This review is an attempt to summarize the current knowledge regarding the effects of nanoparticles on reproductive outcomes. A comprehensive collection of significant experimental nanoreprotoxicity data is presented, which highlight how the toxic effect of nanoparticles can be influenced, not only by the particles’ chemical composition, but also by particle size, surface modification, charge and to a considerable extent on the experimental set‐up. The period around conception is characterized by considerable cytological and molecular restructuring and is therefore particularly sensitive to disturbances. Nanoparticles are able to penetrate through biological barriers into reproductive tissue and at least can have an impact on sperm vitality and function as well as embryo development. Particularly, further investigations are urgently needed on the repetitively shown effect of the ubiquitously used titanium dioxide nanoparticles on the development of the nervous system. It is recommended that future research focuses more on the exact mechanism behind the observed effects, because such information would facilitate the production of nanoparticles with increased biocompatibility.
T‐cell Tolerance to the Developing Equine Conceptus
Authors: Antczak DF 
Published: July 2012

ContentsOne of the most intriguing and dramatic examples of immunological tolerance is displayed by the mammalian foetal–placental unit, which thrives as a semi‐allograft in the mother’s uterus during pregnancy. The success of the so‐called foetal allograft stands in stark contrast to the failure of most tissue and organ grafts to survive without genetic matching of donor and recipient or drastic immunosuppression of the recipient’s immune system. Experiments conducted over the past 60 years have revealed multiple mechanisms that enable the conceptus to avoid immunological detection or destruction. Many of these mechanisms are directed towards evading immune‐mediated damage by maternal T lymphocytes, and they can be grouped into three classes: (i) downregulation of major histocompatibility complex (MHC) gene expression in placental trophoblast cells; (ii) local and systemic alterations in maternal immune reactivity; and (iii) innate defence mechanisms of the trophoblast cells that comprise the barrier between foetal and maternal tissues. The redundancy in these protective mechanisms helps ensure the transmission of life from generation to generation and provides a rich field of study of ways in which functional immunological tolerance can be manifest. The variation in placental forms and function among mammalian species present opportunities to discover and understand novel tolerogenic mechanisms that may have broad application in biology, medicine and animal husbandry. This review focuses on the evidence obtained from studies of pregnancy in the mare that support the case for selective T‐cell tolerance to the mammalian conceptus.
An Amazing 10 Years: The Discovery of Egg and Sperm in the 17th Century
Authors: Cobb M 
Published: July 2012

ContentsThe scientific identification of the key components of sexual reproduction – eggs and sperm – took place during an amazing decade of discovery in the 1660s and 1670s. The names of many of the people involved are now forgotten, and yet their work, and the difficulties they faced and the conflicts they endured, resonate strongly to the present day. Despite this period of innovation, the respective roles of egg and sperm remained unclear for another 170 years. Why did this take so long? And what did people think before these discoveries? By tracing the contours of this major milestone in human knowledge, we can also gain insight into our current knowledge, and the boundaries we may be unwittingly trapped by.
How prepared are rural and remote health care practitioners to provide evidence‐based management for people with chronic lung disease?
Authors: Johnston Catherine Louise , Maxwell Lyndal Jane , Maguire Graeme Paul , Alison Jennifer Ailsey 
Published: July 2012

AbstractObjective:  To investigate the existing experience, training, confidence and knowledge of rural/remote health care practitioners in providing management for people with chronic obstructive pulmonary disease (COPD).Design:  Descriptive cross‐sectional, observational survey design using a written anonymous questionnaire. This study formed part of a larger project evaluating the impact of breathe easy walk easy (BEWE), an interactive education and training program for rural and remote health care practitioners.Setting:  Rural (n = 1, New South Wales) and remote (n = 1, Northern Territory) Australian health care services.Participants:  Health care practitioners who registered to attend the BEWE training program (n = 31).Main outcome measures:  Participant attitudes, objective knowledge and self‐rated experience, training and confidence related to providing components of management for people with COPD.Results:  Participants were from a variety of professional backgrounds (medical, nursing, allied health) but were predominantly nurses (n = 13) or physiotherapists (n = 9). Most participants reported that they had minimal or no experience or training in providing components of management for people with COPD. Confidence was also commonly rated by participants as low. Mean knowledge score (number of correct answers out of 19) was 8.5 (SD = 4.5). Questions relating to disease pathophysiology and diagnosis had higher correct response rates than those relating more specifically to pulmonary rehabilitation.Conclusion:  The results of this study indicate that some rural and remote health care practitioners have low levels of experience, knowledge and confidence related to providing components of management for people with COPD and that education and training with an emphasis on pulmonary rehabilitation would be beneficial.
Survey on breastfeeding among Chinese female physicians and nurses
Authors: Ouyang Yan‐qiong , Xu You‐xian , Zhang Qing 
Published: July 2012

AbstractThe present study investigated knowledge of and beliefs about breastfeeding among Chinese female physicians and nurses and their breastfeeding practices. This study documented knowledge, attitudes and practices of breastfeeding among Chinese medical staff. A total of 367 female physicians and nurses completed a self‐administered, anonymous questionnaire; 96.2% indicated that breastfeeding was natural, but 29.2% thought it difficult. Only 18.5% of the participants questioned breastfeeding women on feeding status, and 12.8% gave breastfeeding advice when asked. After graduation from school, 79.3% of the participants stated that they did not receive training in breastfeeding. In personal practice, 69.2% initiated breastfeeding; 19.1% were still breastfeeding at 4 months, and only three nurses continued breastfeeding for more than 1 year. In conclusion, breastfeeding‐related knowledge is surprisingly poor, and attitudes are less positive. The exclusive breastfeeding rate was found to be low among Chinese female physicians and nurses. The findings highlight the need to re‐educate medical staff on breastfeeding, and imply the need for Baby‐Friendly Hospital Initiative implementation/training.
Recent insights into the diversity, frequency and ecological roles of phenazines in fluorescent Pseudomonas spp.
Authors: Mavrodi Dmitri V. , Parejko James A. , Mavrodi Olga V. , Kwak Youn‐Sig , Weller David M. , Blankenfeldt Wulf , Thomashow Linda S. 
Published: July 2012

SummaryPhenazine compounds represent a large class of bacterial metabolites that are produced by some fluorescent Pseudomonas spp. and a few other bacterial genera. Phenazines were first noted in the scientific literature over 100 years ago, but for a long time were considered to be pigments of uncertain function. Following evidence that phenazines act as virulence factors in the opportunistic human and animal pathogen Pseudomonas aeruginosa and are actively involved in the suppression of plant pathogens, interest in these compounds has broadened to include investigations of their genetics, biosynthesis, activity as electron shuttles, and contribution to the ecology and physiology of the cells that produce them. This minireview highlights some recent and exciting insights into the diversity, frequency and ecological roles of phenazines produced by fluorescent Pseudomonas spp.
Mn‐catalase (Alr0998) protects the photosynthetic, nitrogen‐fixing cyanobacterium Anabaena PCC7120 from oxidative stress
Authors: Banerjee Manisha , Ballal Anand , Apte Shree Kumar 
Published: July 2012

SummaryRole of the non‐haem, manganese catalase (Mn‐catalase) in oxidative stress tolerance is unknown in cyanobacteria. The ORF alr0998 from the Anabaena PCC7120, which encodes a putative Mn‐catalase, was constitutively overexpressed in Anabaena PCC7120 to generate a recombinant strain, AnKat+. The Alr0998 protein could be immunodetected in AnKat+ cells and zymographic analysis showed a distinct thermostable catalase activity in the cytosol of AnKat+ cells but not in the wild‐type Anabaena PCC7120. The observed catalase activity was insensitive to inhibition by azide indicating that Alr0998 protein is indeed a Mn‐catalase. In response to oxidative stress, the AnKat+ showed reduced levels of intracellular ROS which was also corroborated by decreased production of an oxidative stress‐inducible 2‐Cys‐Prx protein. Treatment of wild‐type Anabaena PCC7120 with H2O2 caused (i) RNA degradation in vivo, (ii) severe reduction of photosynthetic pigments and CO2 fixation, (iii) fragmentation and lysis of filaments and (iv) loss of viability. In contrast, the AnKat+ strain was protected from all the aforesaid deleterious effect under oxidative stress. This is the first report on protection of an organism from oxidative stress by overexpression of a Mn‐catalase.
Catalases play differentiated roles in the adaptation of a fungal entomopathogen to environmental stresses
Authors: Wang Zheng‐Liang , Zhang Long‐Bin , Ying Sheng‐Hua , Feng Ming‐Guang 
Published: July 2012

SummaryThe catalase family of Beauveria bassiana (fungal entomopathogen) consists of catA (spore‐specific), catB (secreted), catP (peroxisomal), catC (cytoplasmic) and catD (secreted peroxidase/catalase), which were distinguished in phylogeny and structure and functionally characterized by constructing single‐gene disrupted and rescued mutants for enzymatic and multi‐phenotypic analyses. Total catalase activity decreased 89% and 56% in ΔcatB and ΔcatP, corresponding to the losses of upper and lower active bands gel‐profiled for all catalases respectively, but only 9−12% in other knockout mutants. Compared with wild type and complement mutants sharing similar enzymatic and phenotypic parameters, all knockout mutants showed significant (9−56%) decreases in the antioxidant capability of their conidia (active ingredients of mycoinsecticides), followed by remarkable phenotypic defects associated with the fungal biocontrol potential. These defects included mainly the losses of 40% thermotolerance (45°C) in ΔcatA, 46−48% UV‐B resistance in ΔcatA and ΔcatD, and 33−47% virulence to Spodoptera litura larvae in ΔcatA, ΔcatP and ΔcatD respectively. Moreover, the drastic transcript upregulation of some other catalase genes observed in the normal culture of each knockout mutant revealed functionally complimentary effects among some of the catalase genes, particularly between catB and catC whose knockout mutants displayed little or minor phenotypic changes. However, the five catalase genes functioned redundantly in mediating the fungal tolerance to either hyperosmotic or fungicidal stress. The differentiated roles of five catalases in regulating the B. bassiana virulence and tolerances to oxidative stress, high temperature and UV‐B irradiation provide new insights into fungal adaptation to stressful environment and host invasion.