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1.
An. pediatr. (2003, Ed. impr.) ; 71(1): 60-63, jul. 2009. graf
Article in Spanish | IBECS | ID: ibc-72528

ABSTRACT

Objetivo: Describir la epidemiología del maltrato infantil en el servicio de urgencias de un hospital pediátrico de tercer nivel. Metodología: Estudio descriptivo retrospectivo, desde enero de 2008 a enero de 2006. Se incluyeron pacientes menores de 16 años atendidos en urgencias en los que se sospechó maltrato. Resultados: De un total de 96.419 urgencias, 71 casos (0,07%) fueron por un potencial maltrato (el 45% físico, el 35% sexual y el 20% por negligencia y abandono). La edad media fue de 6 años, sin diferencias entre sexos. El 86% de los casos consultó por sospecha de maltrato. En un 67% de los casos, el posible maltratador convivía en el domicilio con el menor. Se activó la vía sociojurídica en todos los casos. Ingresaron 24 pacientes, 14 por criterio médico y el resto para protección del menor. Dos pacientes quedaron con secuelas neurológicas graves y uno falleció. Se derivó a 8 pacientes a un centro de acogida. Conclusiones: Son necesarias tanto la sensibilización y la formación del personal sanitario para la detección del maltrato como la creación de unidades especializadas para el tratamiento y el seguimiento (AU)


Objective: To describe the epidemiology of child abuse in an emergency department of a tertiary paediatric hospital. Methods: Descriptive and retrospective study from January 2008 to January 2006 including patients less than sixteen years of age who were suspected of being abused during the examination in the emergency department. Results: Child maltreatment was 0.07% of all paediatric emergencies (45% physical abuse, 35% sexual abuse and 20% neglect). Mean age of 6 years old, with no gender differences. 86% were suspected of maltreatment. An adult living with the child was suspected in 67% of cases. Social and judicial procedures were activated. A total of 24 children were admitted, 14 under medical criteria and the rest in order to protect the child; 2 had serious neurological consequences and one died. Eight patients were discharged to social service care centres (AU)


Subject(s)
Humans , Male , Female , Child, Preschool , Child , Adolescent , Child Abuse/statistics & numerical data , Mandatory Reporting/ethics , Child Abuse, Sexual , Health Personnel , Inservice Training , Epidemiology, Descriptive , Retrospective Studies
2.
An Pediatr (Barc) ; 71(1): 60-3, 2009 Jul.
Article in Spanish | MEDLINE | ID: mdl-19423410

ABSTRACT

OBJECTIVE: To describe the epidemiology of child abuse in an emergency department of a tertiary paediatric hospital. METHODS: Descriptive and retrospective study from January 2008 to January 2006 including patients less than sixteen years of age who were suspected of being abused during the examination in the emergency department. RESULTS: Child maltreatment was 0.07% of all paediatric emergencies (45% physical abuse, 35% sexual abuse and 20% neglect). Mean age of 6 years old, with no gender differences. 86% were suspected of maltreatment. An adult living with the child was suspected in 67% of cases. Social and judicial procedures were activated. A total of 24 children were admitted, 14 under medical criteria and the rest in order to protect the child; 2 had serious neurological consequences and one died. Eight patients were discharged to social service care centres. CONCLUSIONS: We believe it is necessary to improve the pediatrician's knowledge of child abuse and to create specialized units.


Subject(s)
Child Abuse/diagnosis , Adolescent , Child , Child, Preschool , Emergency Service, Hospital , Female , Humans , Infant , Male , Retrospective Studies
3.
Cytogenet Genome Res ; 124(2): 128-31, 2009.
Article in English | MEDLINE | ID: mdl-19420924

ABSTRACT

Although their function has not yet been clearly elucidated, interstitial telomeric sequences (ITSs) have been cytogenetically associated with chromosomal reorganizations, fragile sites, and recombination hotspots. In this paper, we show that ITSs are not located at the exact evolutionary breakpoints of the inversions between human and chimpanzee and between human and rhesus macaque chromosomes. We proved that ITSs are not signs of repair in the breakpoints of the chromosome reorganizations analyzed. We found ITSs in the region (0.7-2.7 Mb) flanking one of the two breakpoints in all the inversions assessed. The presence of ITSs in those locations is not by chance. They are short (up to 7.83 repeats) and almost perfect (82.5-97.1% matches). The ITSs are conserved in the species compared, showing that they were present before the reorganizations occurred.


Subject(s)
Chromosome Breakage , Evolution, Molecular , Primates/genetics , Telomere/genetics , Animals , Base Sequence , Chromosomes, Human/genetics , Humans
4.
Cytogenet Genome Res ; 108(1-3): 161-74, 2005.
Article in English | MEDLINE | ID: mdl-15545726

ABSTRACT

In this paper an ancestral karyotype for primates, defining for the first time the ancestral chromosome morphology and the banding patterns, is proposed, and the ancestral syntenic chromosomal segments are identified in the human karyotype. The chromosomal bands that are boundaries of ancestral segments are identified. We have analyzed from data published in the literature 35 different primate species from 19 genera, using the order Scandentia, as well as other published mammalian species as out-groups, and propose an ancestral chromosome number of 2n = 54 for primates, which includes the following chromosomal forms: 1(a+c(1)), 1(b+c(2)), 2a, 2b, 3/21, 4, 5, 6, 7a, 7b, 8, 9, 10a, 10b, 11, 12a/22a, 12b/22b, 13, 14/15, 16a, 16b, 17, 18, 19a, 19b, 20 and X and Y. From this analysis, we have been able to point out the human chromosome bands more "prone" to breakage during the evolutionary pathways and/or pathology processes. We have observed that 89.09% of the human chromosome bands, which are boundaries for ancestral chromosome segments, contain common fragile sites and/or intrachromosomal telomeric-like sequences. A more in depth analysis of twelve different human chromosomes has allowed us to determine that 62.16% of the chromosomal bands implicated in inversions and 100% involved in fusions/fissions correspond to fragile sites, intrachromosomal telomeric-like sequences and/or bands significantly affected by X irradiation. In addition, 73% of the bands affected in pathological processes are co-localized in bands where fragile sites, intrachromosomal telomeric-like sequences, bands significantly affected by X irradiation and/or evolutionary chromosomal bands have been described. Our data also support the hypothesis that chromosomal breakages detected in pathological processes are not randomly distributed along the chromosomes, but rather concentrate in those important evolutionary chromosome bands which correspond to fragile sites and/or intrachromosomal telomeric-like sequences.


Subject(s)
Chromosomal Instability/genetics , Chromosome Banding/methods , Chromosomes, Human/genetics , Conserved Sequence/genetics , Evolution, Molecular , Karyotyping , Alouatta/genetics , Animals , Cebidae/genetics , Cebus/genetics , Cercopithecidae/genetics , Chromosomes, Human, Pair 1/genetics , Chromosomes, Human, Pair 10/genetics , Chromosomes, Human, Pair 7/genetics , Chromosomes, Mammalian/genetics , Gorilla gorilla/genetics , Humans , Pan troglodytes/genetics , Pongo pygmaeus/genetics , Sequence Homology, Nucleic Acid
5.
Cytogenet Genome Res ; 108(1-3): 234-47, 2005.
Article in English | MEDLINE | ID: mdl-15545736

ABSTRACT

The concentration of evolutionary breakpoints in primate karyotypes in some particular regions or chromosome bands suggests that these chromosome regions are more prone to breakage. This is the first extensive comparative study which investigates a possible relationship of two genetic markers (intrachromosomal telomeric sequences [TTAGGG]n, [ITSs] and fragile sites [FSs]), which are implicated in the evolutionary process as well as in chromosome rearrangements. For this purpose, we have analyzed: (a) the cytogenetic expression of aphidicolin-induced FSs in Cebus apella and Cebus nigrivittatus (F. Cebidae, Platyrrhini) and Mandrillus sphinx (F. Cercopithecidae, Catarrhini), and (b) the intrachromosomal position of telomeric-like sequences by FISH with a synthetic (TTAGGG)n probe in C. apella chromosomes. The multinomial FSM statistical model allowed us to determinate 53 FSs in C. apella, 16 FSs in C. nigrivittatus and 50 FSs in M. sphinx. As expected, all telomeres hybridized with the probe, and 55 intrachromosomal loci were also detected in the Cebus apella karyotype. The chi(2) test indicates that the coincidence of the location of Cebus and Mandrillus FSs with the location of human FSs is significant (P < 0.005). Based on a comparative cytogenetic study among different primate species we have identified (or described) the chromosome bands in the karyotypes of Papionini and Cebus species implicated in evolutionary reorganizations. More than 80% of these evolutionary breakpoints are located in chromosome bands that express FSs and/or contain ITSs.


Subject(s)
Cebus/genetics , Chromosome Breakage/genetics , Chromosome Fragile Sites/genetics , Chromosomes, Mammalian/genetics , Evolution, Molecular , Telomere/genetics , Animals , Aphidicolin/pharmacology , Chromosome Fragile Sites/drug effects , Chromosomes, Mammalian/drug effects , Female , Male , Mandrillus/genetics , Metaphase/genetics
6.
Am J Primatol ; 57(4): 177-88, 2002 Aug.
Article in English | MEDLINE | ID: mdl-12210670

ABSTRACT

ZOO-FISH (Fluorescent "in vitro" hybridization) was used to establish the chromosomal homology between humans (HSA) and Cebus nigrivitatus (CNI) and Ateles belzebuth hybridus (ABH). These two species belong to different New World monkey families (Cebidae and Atelidae, respectively) which differ greatly in chromosome number and in chromosome morphology. The molecular results were followed by a detailed banding analysis. The ancestral karyotype of Cebus was then determined by a comparison of in situ hybridization results, as well as chromosomal morphology and banding in other Platyrrhini species. The karyotypes of the four species belonging to the genus Cebus differ from each other by three inversions and one fusion as well as in the location and amounts of heterochromatin. Results obtained by ZOO-FISH in ABH are in general agreement with previous gene-mapping and in situ hybridization data in Ateles, which show that spider monkeys have highly derived genomes. The chromosomal rearrangements detected between HSA and ABH on a band-to-band basis were 27 fusions/fissions, 12 centromeric shifts, and six pericentric inversions. The ancestral karyotype of Cebus was then compared with that of Ateles. The rearrangements detected were 20 fusions/fissions, nine centromeric shifts, and five inversions. Atelidae species are linked by a fragmentation of chromosome 4 into three segments forming an association of 4/15, while Ateles species are linked by 13 derived associations. The results also helped clarify the content of the ancestral platyrrhine karyotype and the mode of chromosomal evolution in these primates. In particular, associations 2/16 and 5/7 should be included in the ancestral karyotype of New World monkeys.


Subject(s)
Cebidae/genetics , Cebus/genetics , Evolution, Molecular , Sequence Homology , Animals , Female , Humans , In Situ Hybridization, Fluorescence , Karyotyping , Male
7.
Hum Genet ; 110(6): 578-86, 2002 Jun.
Article in English | MEDLINE | ID: mdl-12107444

ABSTRACT

The intrachromosomal location of the telomeric sequence in the crab-eating macaque, Macaca fascicularis (F. Cercopithecidae, Catarrhini) has been analysed by fluorescent in situ hybridisation with a long synthetic (TTAGGG)(n) probe. A total of 237 metaphases was analysed. As expected, all telomeres hybridised with the probe and 90 intrachromosomal loci with different hybridisation frequencies were also detected. The chromosomal location of interstitial telomeric sequences in M. fascicularis and in Homo sapiens was then compared, 37 sites (41.11%) being found to be conserved. Some of these sequences can be derived from rearrangements, such as inversions (MFA13q23) or fusions (MFA2p13 and MFA13p12), that have taken place during karyotype evolution.


Subject(s)
Evolution, Molecular , Macaca fascicularis/genetics , Telomere/genetics , Animals , Base Sequence , Chromosome Fragility/genetics , Female , Humans , In Situ Hybridization, Fluorescence , Karyotyping , Species Specificity , Tandem Repeat Sequences
8.
Chromosome Res ; 10(1): 33-44, 2002.
Article in English | MEDLINE | ID: mdl-11863068

ABSTRACT

We have analysed the expression of aphidicolin-induced common fragile sites at two different aphidicolin concentrations (0.1 micromol/L and 0.2 micromol/L) in three female and one male crab-eating macaques (Macaca fascicularis, Cercopithecidae, Catarrhini). A total of 3948 metaphases were analysed: 1754 in cultures exposed to 0.1 micromol/L aphidicolin, 1261 in cultures exposed to 0.2 micromol/L aphidicolin and 933 in controls. The number of breaks and gaps detected ranged from 439 in cultures exposed to 0.1 micromol/L aphidicolin to 2061 in cultures exposed to 0.2 micromol/L aphidicolin. The use of a multinomial FSM statistical model allowed us to identify 95 fragile sites in the chromosomes of M. fascicularis, of which only 16 are expressed in all four specimens. A comparative study between the chromosomes of M. fascicularis and man has demonstrated that 38 human common fragile sites (50%) are found in the equivalent location in M. fascicularis. The analysis of the rearrangements that have taken place during chromosome evolution has revealed that the breakpoints involved in these rearrangements correspond significantly (p < 0.025) to the location of M. fascicularis fragile sites.


Subject(s)
Biological Evolution , Chromosome Fragility/genetics , Chromosomes, Human/genetics , Chromosomes/genetics , Macaca fascicularis/genetics , Animals , Aphidicolin/pharmacology , Chromosome Banding , Chromosome Fragile Sites , Chromosome Mapping , Chromosomes/drug effects , Chromosomes, Human/drug effects , Genetic Markers , Humans , Karyotyping
10.
Am J Primatol ; 49(3): 205-21, 1999 Nov.
Article in English | MEDLINE | ID: mdl-10512541

ABSTRACT

Using G bands, some homologies between the chromosomes of Cebus apella (CAP) and human chromosomes are difficult to establish. To solve this problem, we analyzed these homologies by fluorescence in situ hybridization using human whole chromosome probes (ZOO-FISH). The results indicated that 1) the human probe for chromosome 2 partially hybridizes with CAP chromosomes 13 and 5, 2) the human probe for chromosome 3 partially hybridizes with CAP chromosomes 18 and 20, 3) the human probe for chromosome 9 partially hybridizes with CAP chromosome 19, and 4) the human probe for chromosome 14 hybridizes with the p-terminal and q-terminal regions of CAP chromosome 6. However, none of the human probes employed hybridized with the heterochromatic regions of CAP chromosomes. For this reason, we characterized the heterochromatic regions of CAP chromosomes and of the chromosomes of Pan troglodytes (PTR), to allow comparison between CAP, PTR, and human chromosomes using in situ digestion of fixed chromosomes with the restriction enzymes AluI, HaeIII, and RsaI and by fluorescent staining with DA/DAPI. The results show that 1) centromeric heterochromatin is heterogeneous in the three species studied and 2) noncentromeric heterochromatin is homogeneous within each of the three species, but is different for each species. Thus, centromeric heterochromatin undergoes a higher degree of variability than noncentromeric heterochromatin.


Subject(s)
Cebus/genetics , Chromosomes/chemistry , Heterochromatin/chemistry , Pan troglodytes/genetics , Animals , Chromosomes, Human , Fluorescent Dyes , Humans , In Situ Hybridization, Fluorescence , Indoles , Karyotyping , Restriction Mapping
11.
Mutat Res ; 403(1-2): 185-98, 1998 Jul 17.
Article in English | MEDLINE | ID: mdl-9726019

ABSTRACT

In this paper, we describe the results of a qualitative and quantitative study of chromosomal reorganizations in X-irradiated (1 Gy and 2 Gy) lymphocytes from Macaca fascicularis (MFA) and Erythrocebus patas (EPA). A total of 515 breakpoints in M. fascicularis and 271 breakpoints in E. patas have been detected, identified and localized in the ideogram of the species. The Chi square test indicates that the distribution of breakpoints along the chromosomes is not random in M. fascicularis, and is not random for the p and q arms and bands in both species. Chromosome 5 of M. fascicularis (MFA5), chromosome 1 of E. patas (EPA1), and chromosome arms MFA5q, and EPA 1p are significantly more affected than expected, while chromosome MFA9 is less affected. Terminal regions of chromosome arms accumulate a higher number of breakpoints than the rest of the chromosome (44.4% in M. fascicularis and 45.98% in E. patas); 92.06% and 91.97% of breakpoints are observed in G negative bands in M. fascicularis and E. patas, respectively.


Subject(s)
Chromosome Breakage , Erythrocebus patas/genetics , Macaca fascicularis/genetics , Animals , Chromosome Banding , Chromosomes/radiation effects , Chromosomes/ultrastructure , Erythrocebus patas/blood , Female , In Vitro Techniques , Karyotyping , Lymphocytes/radiation effects , Lymphocytes/ultrastructure , Macaca fascicularis/blood , Male , Species Specificity , Translocation, Genetic
12.
Mutat Res ; 401(1-2): 65-76, 1998 Jun 05.
Article in English | MEDLINE | ID: mdl-9639676

ABSTRACT

In this paper, we describe the results of a qualitative and quantitative study of chromosomal reorganizations observed in X-irradiated (1Gy and 2Gy) and cultured lymphocytes from Cebus apella. A total of 646 breakpoints have been detected, identified and localized in the ideogram of the species. The breakpoint distribution along chromosomes, p and q arms, and bands is not random. Chromosomes #11, #12 and chromosome arms 1p, 12p, 13p, 15p, 11q, and 12q are significantly more affected than expected, while chromosome #19 and chromosome arm 19q are less affected. Terminal regions of chromosome arms accumulate a higher number of breakpoints than the rest of the chromosome (37.82%). A high percentage (93.66%) of breakpoints is found in G negative bands.


Subject(s)
Chromosome Aberrations , Chromosome Disorders , Chromosome Mapping , Lymphocytes/radiation effects , Animals , Cebus , Cells, Cultured , Dose-Response Relationship, Radiation , Female , Karyotyping , Male , X-Rays
13.
J Exp Zool ; 280(1): 38-44, 1998 Jan 01.
Article in English | MEDLINE | ID: mdl-9437850

ABSTRACT

We analyzed the morphological and ultrastructural abnormalities present in two-cell mouse embryos frozen/thawed without the zona pellucida (ZP). Transmission electron microscopy revealed that these embryos had plasma membrane abnormalities that were not observed in the embryos frozen/thawed with an intact ZP. The most frequent anomalies were a decreased number of microvilli with a nonhomogeneous distribution and showing an abnormal morphology and the presence of an increased number of vesicles in the periphery of the cell. The distribution of actin filaments, studied by fluorescence microscopy revealed alterations in both embryos, frozen/ thawed with ZP and embryos frozen/thawed without ZP: an increased staining in some regions of the peripheral actin band, discontinuities or gaps in the band, or the presence of a second actin band connected to the peripheral one.


Subject(s)
Cryopreservation/methods , Embryo, Mammalian/ultrastructure , Zona Pellucida/ultrastructure , Actins/analysis , Animals , Blastomeres/cytology , Blastomeres/physiology , Cell Membrane/chemistry , Cell Membrane/physiology , Cell Membrane/ultrastructure , Embryo, Mammalian/cytology , Embryo, Mammalian/physiology , Female , Mice , Microscopy, Electron , Microscopy, Fluorescence , Microvilli/ultrastructure , Pregnancy , Time Factors , Zona Pellucida/physiology
14.
Cryobiology ; 34(2): 94-106, 1997 Mar.
Article in English | MEDLINE | ID: mdl-9130382

ABSTRACT

Freezing of embryos deprived of the zona pellucida (ZP) decreases their survival rate immediately after thawing, and gives rise to the separation of their blastomeres in a high percentage of cases. We have studied the ultrastructure and the characteristics of actin fibers in the cell-to-cell contact region in mouse embryos frozen-thawed without the ZP at the two-cell stage. Our results indicate that most of the embryos that retain their blastomeres united after freezing and thawing show either the presence of a midbody, or a contact region with a close apposition of the plasma membranes but without an organized actin cortex in their contact region. Only a small percentage of embryos that retain their blastomeres united after freezing and thawing show a contact region with widely separated plasma membranes and an organized actin cytocortex.


Subject(s)
Actins/metabolism , Blastomeres/metabolism , Blastomeres/ultrastructure , Embryo, Mammalian/cytology , Embryo, Mammalian/metabolism , Animals , Cell Adhesion , Cell Separation , Cryopreservation , Female , In Vitro Techniques , Male , Mice , Microscopy, Electron , Microscopy, Electron, Scanning , Microscopy, Fluorescence , Zona Pellucida/ultrastructure
15.
Am J Primatol ; 42(3): 167-78, 1997.
Article in English | MEDLINE | ID: mdl-9209583

ABSTRACT

The chromosomes of 22 animals of four subspecies of the genes Ateles (A. paniscus paniscus, A. p. chamek, A. belzebuth hybridus, and A. b. marginatus) were compared using G/C banding and NOR (nucleolar organizer region) staining methods. The cytogenetic data of Ateles in the literature were also used to clarify the phylogenetic relationships of the species and subspecies and to infer the routes of radiation and speciation of these taxa. Chromosomes 6 and 7 that showed more informative geographic variation and the apomorphic form 4/12, exclusively in A. p. paniscus, are the keys for understanding the evolution, radiation, and specification of the Ateles taxa. The ancestral populations of the genus originated in the southwestern Amazon Basin (the occurrence area of A. paniscus chamek) and spread in the Amazon Basin and westward, crossing the Andes and colonizing Central America and northwesternmost regions of South America. The evolutionary history of the northern South American taxa is interpreted using the model of biogeographical evolution postulated by Haffer [Science 185:131-137, 1969]. Ateles paniscus paniscus is the genetically most differentiated form and probably derives from A. belzebuth hybridus. Based on the karyotype differences, the populations of Ateles can be divided into four different groups. These findings indicate the necessity of a more coherent taxonomic arrangement for the taxa of Ateles.


Subject(s)
Cebidae/classification , Cebidae/genetics , Chromosome Mapping , Phylogeny , Animals , Base Sequence , Chromosome Banding , Conserved Sequence , Karyotyping , Nucleolus Organizer Region/ultrastructure , South America
16.
J Exp Zool ; 272(3): 227-34, 1995 Jun 15.
Article in English | MEDLINE | ID: mdl-7790843

ABSTRACT

Frozen-thawed mouse embryos with (+ZP) and without (-ZP) zona pellucida have been studied at the Scanning Electron Microscope (SEM) to determine how the process affects the plasma membrane and the subsequent embryo development. The main difference observed in -ZP embryos immediately after thawing is the abnormal morphology and distribution of microvilli. This could explain the spontaneous separation of blastomeres in -ZP embryos, and the decrease in their survival rate. If thawed -ZP embryos are allowed to recover in culture, their plasma membrane characteristics and survival rate are identical to those of control embryos.


Subject(s)
Cell Membrane/physiology , Cryopreservation , Embryo, Mammalian , Embryonic and Fetal Development , Animals , Cell Membrane/ultrastructure , Embryo, Mammalian/ultrastructure , Freezing , Mice , Microscopy, Electron, Scanning , Zona Pellucida
17.
Zygote ; 3(1): 27-9, 1995 Feb.
Article in English | MEDLINE | ID: mdl-7613872

ABSTRACT

We describe for the first time the cytogenetic characteristics of mouse 'embryos' obtained by oocyte fusion (oocyte fusion products; OFP). Our results indicate that, after fusion, meiosis II is resumed correctly, with extrusion of two haploid polar bodies, and that metaphase synchronisation of the two haploid sets and chromosome segregation during the first cleavage are also normal.


Subject(s)
Cell Fusion/genetics , Oocytes/cytology , Oocytes/physiology , Animals , Blastomeres/physiology , Chromosomes/genetics , Female , Haploidy , Meiosis , Metaphase/physiology , Mice , Mice, Inbred Strains , Mitosis , Zygote
18.
Am J Primatol ; 37(4): 325-331, 1995.
Article in English | MEDLINE | ID: mdl-31936957

ABSTRACT

Cytogenetic studies have been carried out in 39 specimens of C. apella of different origins. Three different morphologies, one affecting the long arm of chromosome 4 and two affecting pair 17, have been detected. In each case, they can be related by paracentric inversions. Heterochromatin polymorphisms affecting terminal or interstitial C+ regions have also been observed. The length of the terminal heterochromatic region in the long arms of chromosome 11 is variable in C. apella sp., in C. a. paraguayanus and absent in the C. a. nigritus specimens studied. Interstitial C + bands can be observed in the long arms of the biarmed chromosomes 4 and 6, and in the long arms of the acrocentric pairs 12, 13, 17, 18, 19, 20, and 21. Interstitial C + bands in the long arms of chromosomes 4, 12, 17, and 19 are present in all animals studied, although their size is variable, especially in the case of chromosomes 17 and 19. © 1995 Wiley-Liss, Inc.

19.
J Microsc ; 174(Pt 1): 51-4, 1994 Apr.
Article in English | MEDLINE | ID: mdl-8207749

ABSTRACT

A simple method for handling individual specimens that must be processed either for scanning or transmission electron microscopy studies is described. For scanning microscope processing, dehydration is carried out with samples enclosed in small cages made from TAAB capsules in which top and bottom are substituted by plankton nets, and for transmission electron microscopy, samples are preembedded in agarose. This procedure significantly reduces mouth pipetting, dissecting microscope observations, is less labour intensive and, most importantly, reduces sample loss.


Subject(s)
Embryo, Mammalian/ultrastructure , Microscopy, Electron, Scanning/methods , Microscopy, Electron/methods , Oocytes/ultrastructure , Animals , Female , Humans , Mice , Specimen Handling/methods
20.
Zygote ; 2(1): 15-28, 1994 Feb.
Article in English | MEDLINE | ID: mdl-7881912

ABSTRACT

Oocyte fusion induced by inactivated Sendai virus results in the production of 'zygotes' that are able to undergo the first stages of embryonic development. The oocyte fusion products (OFP) obtained follow a morphological developmental pattern equivalent to that of control embryos, at least up to the 8-cell stage. The percentage of OFP that reach the 8-cell stage is extremely low (3%) compared with control embryos cultured in vitro (95%). On light microscopy, the OFP obtained show morphological characteristics identical to control embryos, although their cell diameters are larger. The cortical reaction, meiotic reactivation, extrusion of second polar bodies and pronucleus formation take place as observed in controls. The ultrastructural characteristics of oocyte fusion products at the 1-, 2-, 4- and 8-cell stages are analogous to those of controls, including the presence of structures related to the activation of the embryo genome. However some differences concerning cell ultrastructure, mainly in the nucleus, are observed and discussed in the text.


Subject(s)
Embryo, Mammalian/ultrastructure , Oocytes/cytology , Animals , Cell Fusion , Female , Male , Mice , Microscopy, Electron , Pregnancy
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