Gross morphometry of the heart of the Common marmoset

  The Callithrix jacchus is a Brazilian endemic species that has been widely used asan experimental model in biomedical research. Anatomical data are necessary to support experimental studies with this species. Eleven hearts of C. jacchus from the German Primate Centre (DPZ) have been studied in order to characterize their gross morphometry and compare them with other animal models and human. Biometric data were also obtained. The mean values for morphometry of the hearts did not show any significant difference between male and female. The relative heart weight was similar to human, bovine and equine species. Considering those aspects, the C. jacchus could be used as non-human primate experimental modelfor biomedical studies on heart.

Sperm head morphometry in ejaculates of adult marmosets (Callithrix jacchus): a model for studying sperm subpopulations and among-donor variations

In humans and other mammals, sperm morphology has been considered one of the most important predictive parameters of fertility. The objective was to determine the presence and distribution of sperm head morphometric subpopulations in a nonhuman primate model (Callithrix jacchus), using an objective computer analysis system and principal component analysis (PCA) methods to establish the relationship between the subpopulation distribution observed and among-donor variation. The PCA method revealed a stable number of principal components in all donors studied, that represented more than 85% of the cumulative variance in all cases. After cluster analysis, a variable number (from three to seven) sperm morphometric subpopulations were identified with defined sperm dimensions and shapes. There were differences in the distribution of the sperm morphometric subpopulations (P < 0.001) in all ejaculates among the four donors analyzed. In conclusion, in this study, computerized sperm analysis methods combined with PCA cluster analyses were useful to identify, classify, and characterize various head sperm morphometric subpopulations in nonhuman primates, yielding considerable biological information. In addition, because all individuals were kept in the same conditions, differences in the distribution of these subpopulations were not attributed to external or management factors. Finally, the substantial information derived from subpopulation analyses provided new and relevant biological knowledge which may have a practical use for future studies in human and nonhuman primate ejaculates, including identifying individuals more suitable for assisted reproductive technologies. (c) 2012 Elsevier Inc. All rights reserved.Spanish Government (MAE) [2010-IA

Rapidly evolving marmoset MSMB genes are differently expressed in the male genital tract

BACKGROUND: Beta-microseminoprotein, an abundant component in prostatic fluid, is encoded by the potential tumor suppressor gene MSMB. Some New World monkeys carry several copies of this gene, in contrast to most mammals, including humans, which have one only. Here we have investigated the background for the species difference by analyzing the chromosomal organization and expression of MSMB in the common marmoset (Callithrix jacchus). METHODS: Genes were identified in the Callithrix jacchus genome database using bioinformatics and transcripts were analyzed by RT-PCR and quantified by real time PCR in the presence of SYBR green. RESULTS: The common marmoset has five MSMB: one processed pseudogene and four functional genes. The latter encompass homologous genomic regions of 32-35 kb, containing the genes of 12-14 kb and conserved upstream and downstream regions of 14-19 kb and 3-4 kb. One gene, MSMB1, occupies the same position on the chromosome as the single human gene. On the same chromosome, but several Mb away, is another MSMB locus situated with MSMB2, MSMB3 and MSMB4 arranged in tandem. Measurements of transcripts demonstrated that all functional genes are expressed in the male genital tract, generating very high transcript levels in the prostate. The transcript levels in seminal vesicles and testis are two and four orders of magnitude lower. A single gene, MSMB3, accounts for more than 90% of MSMB transcripts in both the prostate and the seminal vesicles, whereas in the testis around half of the transcripts originate from MSMB2. These genes display rapid evolution with a skewed distribution of mutated nucleotides; in MSMB2 they affect nucleotides encoding the N-terminal Greek key domain, whereas in MSMB3 it is the C-terminal MSMB-unique domain that is affected. CONCLUSION: Callitrichide monkeys have four functional MSMB that are all expressed in the male genital tract, but the product from one gene, MSMB3, will predominate in seminal plasma. This gene and MSMB2, the predominating testicular gene, have accumulated mutations that affect different parts of the translation products, suggesting an ongoing molecular specialization that presumably yields functional differences in accessory sex glands and testis

The spatial extent of tephra deposition and environmental impacts from the 1912 Novarupta eruption

The eruption of Novarupta within the Katmai Volcanic Cluster, south-west Alaska, in June 1912 was the most voluminous eruption of the twentieth century but the distal distribution of tephra deposition is inadequately quantified. We present new syntheses of published tephrostratigraphic studies and a large quantity of previously un-investigated historical records. For the first time, we apply a geostatistical technique, indicator kriging, to integrate and interpolate such data. Our results show evidence for tephra deposition across much of Alaska, Yukon, the northern Pacific, western British Columbia and northwestern Washington. The most distal tephra deposition was observed around 2,500 km downwind from the volcano. Associated with tephra deposition are many accounts of acid deposition and consequent impacts on vegetation and human health. Kriging offers several advantages as a means to integrate and present such data. Future eruptions of a scale similar to the 1912 event have the potential to cause widespread disruption. Historical records of tephra deposition extend far beyond the limit of deposition constrained by tephrostratigraphic records. The distal portion of tephra fallout deposits is rarely adequately mapped by tephrostratigraphy alone; contemporaneous reports of fallout can provide important constraints on the extent of impacts following large explosive eruptions

Alkaline Phosphatases: Structure, substrate specificity and functional relatedness to other members of a large superfamily of enzymes

Our knowledge of the structure and function of alkaline phosphatases has increased greatly in recent years. The crystal structure of the human placental isozyme has enabled us to probe salient features of the mammalian enzymes that differ from those of the bacterial enzymes. The availability of knockout mice deficient in each of the murine alkaline phosphatase isozymes has also given deep insights into their in vivo role. This has been particularly true for probing the biological role of bone alkaline phosphatase during skeletal mineralization. Due to space constraints this mini-review focuses exclusively on structural and functional features of mammalian alkaline phosphatases as identified by crystallography and probed by site-directed mutagenesis and kinetic analysis. An emphasis is also placed on the substrate specificity of alkaline phosphatases, their catalytic properties as phosphohydrolases as well as phosphodiesterases and their structural and functional relatedness to a large superfamily of enzymes that includes nucleotide pyrophosphatase/phosphodiesterase

Inhibition of pyrophosphatase activity of mouse duodenal alkaline phosphatase by magnesium ions

Duodenal alkaline phosphatase of juvenile (11-day-old) mice, like other non-specific alkaline phosphatases, has the ability to hydrolyse PP(i). When a constant Mg(2+)/PP(i) concentration ratio is maintained, plots of velocity as a function of PP(i) concentration are consistent with Michaelis–Menten kinetics. Mg(2+) activates pyrophosphate hydrolysis and maximal activity is obtained at a constant Mg(2+)/PP(i) concentration ratio of 0·66. At higher ratios there is strong inhibition. At constant concentrations of Mg(2+) and increasing concentrations of PP(i), the velocity–substrate (PP(i)) concentration plots show sigmoidal dependence. By assuming that the true substrate is MgP(2)O(7)(2−) complex, and using complexity constants, the concentrations of free Mg(2+), Mg(2)P(2)O(7) and MgP(2)O(7)(2−) were calculated in assay mixtures ranging in PP(i) concentration from 0·1 to 2·5mm and in total Mg(2+) concentration from 0·6 to 2·6mm. From these data, the concentrations of added Mg(2+) and PP(i) in the assay mixtures were selected so that the velocity could be measured (1) at three fixed concentrations of free Mg(2+) ions with varied concentrations of MgP(2)O(7)(2−) and (2) at four fixed concentrations of Mg(2)P(2)O(7) with varied concentrations of MgP(2)O(7)(2−). Lineweaver–Burk and Hill plots from these data showed that the inhibition is caused by free Mg(2+) ions, of a mixed type and consistent with Michaelis–Menten kinetics. The sigmoidal dependence observed between velocity and PP(i) concentration at constant concentration of total Mg(2+) is therefore not due to allosteric inhibition. It is due to a combined effect of (1) inhibition by free Mg(2+) ions, (2) depletion of the true substrate, MgP(2)O(7)(2−), owing to the formation of Mg(2)P(2)O(7) and (3) the manner in which the concentrations of these three molecular or ionic species change when PP(i) concentration is increased maintaining the total Mg(2+) concentration constant

Effects of ovarian stimulation, with and without human chorionic gonadotrophin, on oocyte meiotic and developmental competence in the marmoset monkey (Callithrix jacchus)

Copyright © 2007 Elsevier Inc. All rights reserved.A reliable ovarian stimulation protocol for marmosets is needed to enhance their use as a model for studying human and non-human primate oocyte biology. In this species, a standard dose of hCG did not effectively induce oocyte maturation in vivo. The objectives of this study were to characterize ovarian response to an FSH priming regimen in marmosets, given without or with a high dose of hCG, and to determine the meiotic and developmental competence of the oocytes isolated. Ovaries were removed from synchronized marmosets treated with FSH alone (50 IU/d for 6 d) or the same FSH treatment combined with a single injection of hCG (500 IU). Cumulus-oocyte complexes (COCs) were isolated from large (>1.5mm) and small (0.7-1.5mm) antral follicles. In vivo-matured oocytes were subsequently activated parthenogenetically or fertilized in vitro. Immature oocytes were subjected to in vitro maturation and then activated parthenogenetically. Treatment with FSH and hCG combined increased the number of expanded COCs from large antral follicles compared with FSH alone (23.5 +/- 9.3 versus 6.4 +/- 2.7, mean +/- S.E.M.). Approximately 90% of oocytes surrounded by expanded cumulus cells at the time of isolation were meiotically mature. A blastocyst formation rate of 47% was achieved following fertilization of in vivo-matured oocytes, whereas parthenogenetic activation failed to induce development to the blastocyst stage. The capacity of oocytes to complete meiosis in vitro and cleave was positively correlated with follicle diameter. A dramatic effect of follicle size on spindle formation was observed in oocytes that failed to complete meiosis in vitro. Using the combined FSH and hCG regimen described in this study, large numbers of in vivo matured marmoset oocytes could be reliably collected in a single cycle, making the marmoset a valuable model for studying oocyte maturation in human and non-human primates.C.G. Grupen, R.B. Gilchrist, P.L. Nayudu, M.F. Barry, S.J. Schulz, L.J. Ritter and D.T. Armstronghttp://www.elsevier.com/wps/find/journaldescription.cws_home/525024/description#descriptio

Validation of non-fluorescent methods to reliably detect acrosomal and plasma membrane integrity of common marmoset (Callithrix jacchus) sperm

German Primate Centre. Reproductive Biology Department. Germany / University of Sao Paulo. Faculty of Veterinary Medicine and Animal Science. Department of Animal Reproduction. São Paulo, SP, Brazil.University of Sao Paulo. Faculty of Veterinary Medicine and Animal Science. Department of Surgery. São Paulo, SP, Brazil.University of Sao Paulo. Faculty of Veterinary Medicine and Animal Science. Department of Animal Reproduction. São Paulo, SP, Brazil.Ministério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Centro Nacional de Primatas. Ananindeua, PA, Brasil.German Primate Centre. Reproductive Biology Department. Germany.University of Sao Paulo. Faculty of Veterinary Medicine and Animal Science. Department of Animal Reproduction. São Paulo, SP, Brazil.Simple, rapid and stable sperm evaluation methods which have been optimized for common marmoset (Callithrix jacchus) are critical for studies involving collection and evaluation of sperm in the field. This is particularly important for new species groups such as Callitrichidae where the sperm have been little studied. Of this family, C. jacchus is the best known, and has been chosen as a model species for other members of the genus Callithrix. The fundamental evaluation parameters for sperm of any species are viability and acrosomal status. Semen samples were collected by penile vibratory stimulation. To evaluate sperm plasma membrane integrity, Eosin-Nigrosin was tested here for the common marmoset sperm to be used under field conditions. Further, a non-fluorescent stain for acrosome, the "Simple" stain, developed for domestic and wild cats, was tested on common marmoset sperm. This was compared with a fluorescent staining, Fluorescein isothiocyanate-Pisum sativum agglutinin (FITC-PSA), routinely used and validated for common marmoset at the German Primate Centre to evaluate acrosomal integrity. Results obtained with the "Simple" stain showed a marked differentiation between sperm with intact and non-intact acrosome both with and without ionophore treatment and closely correlated with results obtained with FITC-PSA. Temperature had no effect on the results with the "Simple" stain and the complete processing is simple enough to be carried out under field conditions. These findings indicated that the "Simple" stain and Eosin-Nigrosin provide rapid and accurate results for C. jacchus sperm and that those methods can be reliably used as field tools for sperm evaluation for this species