Spermatology for understanding, managing and conserving rare species

1995 ◽  
Vol 7 (4) ◽  
pp. 811 ◽  
Author(s):  
D Wildt ◽  
B Pukazhenthi ◽  
J Brown ◽  
S Monfort ◽  
J Howard ◽  
...  
Keyword(s):  
Mammalian Species ◽  
Laboratory Animals ◽  
Multidisciplinary Research ◽  
Endangered Species Management ◽  
Species Survival ◽  
Crucial Component ◽  
Species Management ◽  
Management Plans ◽  
And Function ◽  
Unique Species

Most conventional spermatology research involves common mammalian species including livestock, laboratory animals and humans. Yet, there are more than 4500 mammalian species inhabiting the planet for which little is known about basic reproductive biology, including sperm characteristics and function. This information is important, not just as adjunct knowledge, but because the majority of these species are threatened with extinction, largely due to human-induced pressures. The field of conservation is changing rapidly, and global cooperation is emerging among a variety of wildlife enthusiasts, ranging from management authorities of nature reserves to curators of rare zoological collections. Conservation progress depends on systematic, multidisciplinary research first to answer basic questions, with new data then applied to endangered species management plans. The reproductive physiologist is a crucial component of this scheme. Reproduction is the essence of species survival, and enormous effort needs to be directed at these 'untraditional' research species, subspecies and populations. Spermatology research combined with simultaneous efforts in endocrinology, embryology and cryopreservation (among others) can lead to the successful application of assisted reproduction. Examples from this laboratory include an array of wild felid species and a rare cervid and mustelid. Obstacles to success are formidable, including unique species-specificities, diminished genetic diversity and a general lack of resources. Nonetheless, the field offers tremendous opportunities for generating unique knowledge of comparative interest and with conservation utility.

Cities-Before-Cities

2017 ◽  
Author(s):  
Daniel W. Berman
Keyword(s):  
Crucial Role ◽  
The West ◽  
Central Greece ◽  
Form And Function ◽  
South Italy ◽  
Crucial Component ◽  
And Function ◽  
The City

Foundation myths are a crucial component of many Greek cities’ identities. But the mythic tradition also represents many cities and their spaces before they were cities at all. This study examines three of these ‘prefoundational’ narratives: stories of cities-before-cities that prepare, configure, or reconfigure, in a conceptual sense, the mythic ground for foundation. ‘Prefoundational’ myths vary in both form and function. Thebes, before it was Thebes, is represented as a trackless and unfortified backwater. Croton, like many Greek cities in south Italy, credited Heracles with a kind of ‘prefounding’, accomplished on his journey from the West back to central Greece. And the Athenian acropolis was the object of a quarrel between Athena and Poseidon, the results of which gave the city its name and permanently marked its topography. In each case, ‘prefoundational’ myth plays a crucial role in representing ideology, identity, and civic topography.

Sex Steroids and Human Behavior: Implications for Developmental Psychopathology

CNS Spectrums ◽  
2001 ◽  
Vol 6 (1) ◽  
pp. 75-88 ◽  
Author(s):  
Gerianne M. Alexander ◽  
Bradley S. Peterson
Keyword(s):  
Sex Differences ◽  
Human Behavior ◽  
Sex Steroids ◽  
Developmental Psychopathology ◽  
Mammalian Species ◽  
Brain Structures ◽  
Postnatal Life ◽  
Brain Structure And Function ◽  
Atypical Development ◽  
And Function

AbstractIn a variety of mammalian species, prenatal androgens organize brain structures and functions that are later activated by steroid hormones in postnatal life. In humans, studies of individuals with typical and atypical development suggest that sex differences in reproductive and nonreproductive behavior derive in part from similar prenatal and postnatal steroid effects on brain development. This paper provides a summary of research investigating hormonal influences on human behavior and describes how sex differences in the prevalences and natural histories of developmental psychopathologies may be consistent with these steroid effects. An association between patterns of sexual differentiation and specific forms of psychopathology suggests novel avenues for assessing the effects of sex steroids on brain structure and function, which may in turn improve our understanding of typical and atypical development in women and men.

scholarly journals Centromere Protein B Null Mice are Mitotically and Meiotically Normal but Have Lower Body and Testis Weights

1998 ◽  
Vol 141 (2) ◽  
pp. 309-319 ◽  
Author(s):  
Damien F. Hudson ◽  
Kerry J. Fowler ◽  
Elizabeth Earle ◽  
Richard Saffery ◽  
Paul Kalitsis ◽  
...  
Keyword(s):  
Cell Cycle Progression ◽  
Mammalian Species ◽  
Experimental Studies ◽  
Conflicting Evidence ◽  
Body Weights ◽  
Reduced Rate ◽  
And Function ◽  
Centromere Assembly ◽  
Mitosis And Meiosis

CENP-B is a constitutive centromere DNA-binding protein that is conserved in a number of mammalian species and in yeast. Despite this conservation, earlier cytological and indirect experimental studies have provided conflicting evidence concerning the role of this protein in mitosis. The requirement of this protein in meiosis has also not previously been described. To resolve these uncertainties, we used targeted disruption of the Cenpb gene in mouse to study the functional significance of this protein in mitosis and meiosis. Male and female Cenpb null mice have normal body weights at birth and at weaning, but these subsequently lag behind those of the heterozygous and wild-type animals. The weight and sperm content of the testes of Cenpb null mice are also significantly decreased. Otherwise, the animals appear developmentally and reproductively normal. Cytogenetic fluorescence-activated cell sorting and histological analyses of somatic and germline tissues revealed no abnormality. These results indicate that Cenpb is not essential for mitosis or meiosis, although the observed weight reduction raises the possibility that Cenpb deficiency may subtly affect some aspects of centromere assembly and function, and result in reduced rate of cell cycle progression, efficiency of microtubule capture, and/or chromosome movement. A model for a functional redundancy of this protein is presented.

Regulation of sperm motility at the axonemal level

1995 ◽  
Vol 7 (4) ◽  
pp. 847 ◽  
Author(s):  
C Gagnon
Keyword(s):  
Direct Action ◽  
Mammalian Species ◽  
Basic Structure ◽  
Structure And Function ◽  
Structural Components ◽  
Long Period ◽  
Different Types ◽  
Radial Spokes ◽  
Dynein Arms ◽  
And Function

With very few exceptions, the basic structure of the 9+2 axoneme has been well preserved over a very long period of evolution from protozoa to mammais. This stability indicates that the basic structural components of the axoneme visible by electron microscopy, as well as most of the other unidentified components, have withstood the passage of time. It also means that components of the 9+2 axoneme have sufficient diversity in function to accommodate the various types of motility patterns encountered in different species of flagella. Several of the 200 polypeptides that constitute the axoneme have been identified as components of the dynein arms, radial spokes etc. but many more remain to be identified and their function(s) remain to be determined. Because this review deals with the regulation of flagellar movement at the axonemal level, it does not include regulation of flagella by extracellular factors unless these factors have a direct action on axonemal components. In this context, it is very important firstly to understand the structural components of the axoneme and how they influence and regulate axonemal movement. Different primitive organisms are mentioned in this review since major breakthroughs in our understanding of how an axoneme generates different types of movement have been made through their study. Despite some variations in structure and function of axonemal components, the basic mechanisms involved in the regulation of flagella from Chlamydomonas or sea urchin spermatozoa should also apply to the more evolved mammalian species, including human spermatozoa.

scholarly journals The IUCN-SSC Cave Invertebrate Specialist Group

2018 ◽  
Vol 1 ◽  
Author(s):  
Louis Deharveng ◽  
Tony Whitten ◽  
Judson Wynne ◽  
Ana Komericki ◽  
Sonia Khela
Keyword(s):  
Social Impact ◽  
Narrow Range ◽  
Iucn Red List ◽  
Red List ◽  
Business Sector ◽  
Conservation Priority ◽  
The Past ◽  
Species Survival ◽  
Management Plans ◽  
Specialist Group

The Cave Invertebrate Specialist Group, an IUCN Species Survival Commission, is a group of 80 taxonomists, biospeleologists, ecologists, and conservation biologists. Since 2014, our objectives have been to: (1) conserve subterranean habitats, and address one of the largest lacunas in conservation biology – the protection of sensitive cave and subterranean invertebrate populations; (2) conduct IUCN Red List evaluations for imperiled and/or narrow range endemic species; (3) encourage comprehensive baseline biodiversity surveys, in particular to determine the proportion of unknown biodiversity yet to be discovered; and, (4) provide collaborative opportunities with the business sector for conducting Environmental and Social Impact Assessments, Biodiversity Action Plans, and site and species management plans. We will our accomplishments over the past four years including growth of membership, the number of Red List evaluations conducted and the total number of species recognized as a conservation priority.

scholarly journals Adult neurogenesis in natural populations

2001 ◽  
Vol 79 (4) ◽  
pp. 297-302 ◽  
Author(s):  
R Boonstra ◽  
L Galea ◽  
S Matthews ◽  
J M Wojtowicz
Keyword(s):  
Adult Neurogenesis ◽  
Mammalian Species ◽  
Natural Populations ◽  
Hippocampal Neurogenesis ◽  
Adult Brain ◽  
Biologically Relevant ◽  
Evolutionarily Conserved ◽  
Functional Consequences ◽  
Song Production ◽  
And Function

The dogma that the adult brain produces no new neurons has been overturned, but the critics are still asking, so what? Is adult neurogenesis a biologically relevant phenomenon, or is it perhaps harmful because it disrupts the existing neuronal circuitry? Considering that the phenomenon is evolutionarily conserved in all mammalian species examined to date and that its relevance has been well documented in non-mammalian species, it seems self-evident that neurogenesis in adult mammals must have a role. In birds, it has been established that neurogenesis varies dramatically with seasonal changes in song production. In chickadees, the learning behaviour related to finding stored food is also correlated with seasonal adult neurogenesis. Such studies are still nonexistent in mammals, but the related evidence suggests that neurogenesis does vary seasonally in hamsters and shows sexual differences in meadow voles. To promote studies on natural populations asking fundamental questions of the purpose and function of neurogenesis, we organized a Workshop on "Hippocampal Neurogenesis in Natural Populations" in Toronto in May 2000. The Workshop highlighted recent discoveries in neurogenesis from the lab, and focused on its functional consequences. The consensus at the Workshop was that demonstration of a role for neurogenesis in natural behaviours will ultimately be essential if we are to understand the purpose and function of neurogenesis in humans.Key words: neurogenesis, hippocampus, dentate gyrus, learning, memory, wild population.

P3 Outcomes following diagnostic brain biopsy: a 1 year case review

2019 ◽  
Vol 90 (3) ◽  
pp. e27.3-e27
Author(s):  
R Ingleton ◽  
B Gorgun ◽  
N Gorgun ◽  
M Hayder ◽  
RR Vindlacheruvu
Keyword(s):  
Brain Biopsy ◽  
Low Grade ◽  
Case Review ◽  
Electronic Patient Records ◽  
Stereotactic Brain Biopsy ◽  
Neurosurgical Procedure ◽  
Tissue Diagnosis ◽  
Radiology Reports ◽  
Crucial Component ◽  
Management Plans

ObjectivesStereotactic brain biopsy is an established neurosurgical procedure utilised in times of diagnostic or therapeutic uncertainty. Achieving a definitive tissue diagnosis allows tailored surgical, medical or oncological management. We present a 1 year case review of brain biopsies and compare suspected pre-operative diagnosis with final tissue outcome.DesignRetrospective analysis of all brain biopsies performed in 2017 in an adult-only neurosurgical unit.SubjectsAll patients undergoing brain biopsy.MethodsTheatre records were retrospectively analysed to identify patients undergoing brain biopsy in 2017. Further information was obtained using electronic patient records and radiology reports.Results41 patients underwent brain biopsy in 2017. Only 1 proved inconclusive and required repeat procedure. 26 patients had a suspected diagnosis documented pre-operatively based on radiological/clinical evidence. The most commonly suspected pathologies were low grade and high grade gliomas (9 and 15 patients). Of 25 patients with both a pre-operative differential and subsequent conclusive tissue diagnosis, 10 (40%) were ultimately given diagnoses which did not match the suspected pathology. Significantly, 1 biopsy diagnosed cerebral lymphoma.ConclusionsBrain biopsy is a relatively safe and simple neurosurgical procedure which can reliably provide a definitive tissue diagnosis. We have demonstrated how it remains a crucial component in formally establishing diagnosis prior to determining optimum management plans.

The Placenta as an Organ and a Source of Stem Cells and Extracellular Matrix: A Review

2016 ◽  
Vol 201 (4) ◽  
pp. 239-252 ◽  
Author(s):  
Sonja E. Lobo ◽  
Luciano César P.C. Leonel ◽  
Carla M.F.C. Miranda ◽  
Talya M. Coelho ◽  
Guilherme A.S. Ferreira ◽  
...  
Keyword(s):  
Stem Cells ◽  
Extracellular Matrix ◽  
Progenitor Cells ◽  
Fetal Development ◽  
Mammalian Species ◽  
Bioactive Molecules ◽  
High Yield ◽  
Temporal Dynamic ◽  
Embryonic And Fetal Development ◽  
And Function

The placenta is a temporal, dynamic and diverse organ with important immunological features that facilitate embryonic and fetal development and survival, notwithstanding the fact that several aspects of its formation and function closely resemble tumor progression. Placentation in mammals is commonly used to characterize the evolution of species, including insights into human evolution. Although most placentas are discarded after birth, they are a high-yield source for the isolation of stem/progenitor cells and are rich in extracellular matrix (ECM), representing an important resource for regenerative medicine purposes. Interactions among cells, ECM and bioactive molecules regulate tissue and organ generation and comprise the foundation of tissue engineering. In the present article, differences among several mammalian species regarding the placental types and classifications, phenotypes and potency of placenta-derived stem/progenitor cells, placental ECM components and current placental ECM applications were reviewed to highlight their potential clinical and biomedical relevance.

Sign in / Sign up

Export Citation Format

Share Document