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1.
Rev Fish Biol Fish ; 32(1): 101-121, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34092936

RESUMEN

Food from the sea can make a larger contribution to healthy and sustainable diets, and to addressing hunger and malnutrition, through improvements in production, distribution and equitable access to wild harvest and mariculture resources and products. The supply and consumption of seafood is influenced by a range of 'drivers' including ecosystem change and ocean regulation, the influence of corporations and evolving consumer demand, as well as the growing focus on the importance of seafood for meeting nutritional needs. These drivers need to be examined in a holistic way to develop an informed understanding of the needs, potential impacts and solutions that align seafood production and consumption with relevant 2030 Sustainable Development Goals (SDGs). This paper uses an evidence-based narrative approach to examine how the anticipated global trends for seafood might be experienced by people in different social, geographical and economic situations over the next ten years. Key drivers influencing seafood within the global food system are identified and used to construct a future scenario based on our current trajectory (Business-as-usual 2030). Descriptive pathways and actions are then presented for a more sustainable future scenario that strives towards achieving the SDGs as far as technically possible (More sustainable 2030). Prioritising actions that not only sustainably produce more seafood, but consider aspects of access and utilisation, particularly for people affected by food insecurity and malnutrition, is an essential part of designing sustainable and secure future seafood systems. Supplementary Information: The online version contains supplementary material available at 10.1007/s11160-021-09663-x.

2.
mSystems ; 5(2)2020 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-32156798

RESUMEN

Soil ecosystems harbor diverse microorganisms and yet remain only partially characterized as neither single-cell sequencing nor whole-community sequencing offers a complete picture of these complex communities. Thus, the genetic and metabolic potential of this "uncultivated majority" remains underexplored. To address these challenges, we applied a pooled-cell-sorting-based mini-metagenomics approach and compared the results to bulk metagenomics. Informatic binning of these data produced 200 mini-metagenome assembled genomes (sorted-MAGs) and 29 bulk metagenome assembled genomes (MAGs). The sorted and bulk MAGs increased the known phylogenetic diversity of soil taxa by 7.2% with respect to the Joint Genome Institute IMG/M database and showed clade-specific sequence recruitment patterns across diverse terrestrial soil metagenomes. Additionally, sorted-MAGs expanded the rare biosphere not captured through MAGs from bulk sequences, exemplified through phylogenetic and functional analyses of members of the phylum Bacteroidetes Analysis of 67 Bacteroidetes sorted-MAGs showed conserved patterns of carbon metabolism across four clades. These results indicate that mini-metagenomics enables genome-resolved investigation of predicted metabolism and demonstrates the utility of combining metagenomics methods to tap into the diversity of heterogeneous microbial assemblages.IMPORTANCE Microbial ecologists have historically used cultivation-based approaches as well as amplicon sequencing and shotgun metagenomics to characterize microbial diversity in soil. However, challenges persist in the study of microbial diversity, including the recalcitrance of the majority of microorganisms to laboratory cultivation and limited sequence assembly from highly complex samples. The uncultivated majority thus remains a reservoir of untapped genetic diversity. To address some of the challenges associated with bulk metagenomics as well as low throughput of single-cell genomics, we applied flow cytometry-enabled mini-metagenomics to capture expanded microbial diversity from forest soil and compare it to soil bulk metagenomics. Our resulting data from this pooled-cell sorting approach combined with bulk metagenomics revealed increased phylogenetic diversity through novel soil taxa and rare biosphere members. In-depth analysis of genomes within the highly represented Bacteroidetes phylum provided insights into conserved and clade-specific patterns of carbon metabolism.

3.
Science ; 283(5400): 404-6, 1999 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-9888858

RESUMEN

Mutator genotypes with increased mutation rates may be especially important in microbial evolution if genetic adaptation is generally limited by the supply of mutations. In experimental populations of the bacterium Escherichia coli, the rate of evolutionary adaptation was proportional to the mutation supply rate only in particular circumstances of small or initially well-adapted populations. These experiments also demonstrate a "speed limit" on adaptive evolution in asexual populations, one that is independent of the mutation supply rate.


Asunto(s)
Evolución Biológica , Escherichia coli/genética , Modelos Biológicos , Mutación , Adaptación Fisiológica , Escherichia coli/fisiología , Genética de Población , Genotipo , Modelos Lineales
4.
Arch Pediatr ; 26(3): 161-167, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30885605

RESUMEN

BACKGROUND: Recreational scuba diving has been authorized for type 1 diabetics over 18 years old - the age of majority in France - since 2004, but it remained forbidden for younger diabetics by the French underwater federation (FFESSM). Here, we present a study to evaluate: - the conditions under which diving could be authorized for 14- to 18 year olds with type 1 diabetes; - the value of continuous glucose monitoring (CGM) while diving. A secondary objective was to monitor the impact of diving on the teenagers' quality of life. SUBJECT AND METHODS: Sixteen adolescents (14-17.5 years old) were included. Diabetes was known for 6 years (range, 1-14) and Hb1Ac was 9.0% (range, 7.7-11.9). The study was conducted in Mayotte with both capillary glycemia (CG) and CGM measurements taken during five dives. RESULTS: The average CG prior to diving was 283mg/dL and decreased by 75±76mg/dL during the dive. No hypoglycemia occurred during the dives and four episodes occurred after. Glycemia variations during dives and for the overall duration of the study were greater than for adults, most likely due to the general adolescent behavior, notably regarding diet and diabetes management. CGM was greatly appreciated by the adolescents. They had an overall satisfactory quality of life. No significant variations were observed during the entire course of the study. CONCLUSIONS: Although in need of further studies, these preliminary results show that CGM can be used while diving. CGM records show a continuous decrease of glycemia during dives. Based on these results, the French underwater federation has now authorized diving for adolescent type 1 diabetics following a specific diving protocol that includes HbA1c<8.5%, autonomous management of diabetes by the adolescent, reduction of insulin doses, and target glycemia prior to the dive>250mg/dL.


Asunto(s)
Automonitorización de la Glucosa Sanguínea , Diabetes Mellitus Tipo 1/sangre , Buceo , Adolescente , Glucemia/análisis , Comoras , Buceo/legislación & jurisprudencia , Femenino , Francia , Hemoglobina Glucada/análisis , Regulación Gubernamental , Humanos , Masculino
5.
PLoS One ; 13(5): e0196092, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29723211

RESUMEN

Accurate information on the growth rates of fish is crucial for fisheries stock assessment and management. Empirical life history parameters (von Bertalanffy growth) are widely fitted to cross-sectional size-at-age data sampled from fish populations. This method often assumes that environmental factors affecting growth remain constant over time. The current study utilized longitudinal life history information contained in otoliths from 412 juveniles and adults of gilthead seabream, Sparus aurata, a commercially important species fished and farmed throughout the Mediterranean. Historical annual growth rates over 11 consecutive years (2002-2012) in the Gulf of Lions (NW Mediterranean) were reconstructed to investigate the effect of temperature variations on the annual growth of this fish. S. aurata growth was modelled linearly as the relationship between otolith size at year t against otolith size at the previous year t-1. The effect of temperature on growth was modelled with linear mixed effects models and a simplified linear model to be implemented in a cohort Integral Projection Model (cIPM). The cIPM was used to project S. aurata growth, year to year, under different temperature scenarios. Our results determined current increasing summer temperatures to have a negative effect on S. aurata annual growth in the Gulf of Lions. They suggest that global warming already has and will further have a significant impact on S. aurata size-at-age, with important implications for age-structured stock assessments and reference points used in fisheries.


Asunto(s)
Modelos Estadísticos , Dorada/crecimiento & desarrollo , Temperatura , Animales , Membrana Otolítica/crecimiento & desarrollo , Dorada/anatomía & histología
6.
Trends Genet ; 16(7): 315-20, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10858662

RESUMEN

Many mitochondrial and plastid proteins are derived from their bacterial endosymbiotic ancestors, but their genes now reside on nuclear chromosomes instead of remaining within the organelle. To become an active nuclear gene and return to the organelle as a functional protein, an organellar gene must first be assimilated into the nuclear genome. The gene must then be transcribed and acquire a transit sequence for targeting the protein back to the organelle. On reaching the organelle, the protein must be properly folded and modified, and in many cases assembled in an orderly manner into a larger protein complex. Finally, the nuclear copy must be properly regulated to achieve a fitness level comparable with the organellar gene. Given the complexity in establishing a nuclear copy, why do organellar genes end up in the nucleus? Recent data suggest that these genes are worse off than their nuclear and free-living counterparts because of a reduction in the efficiency of natural selection, but do these population-genetic processes drive the movement of genes to the nucleus? We are now at a stage where we can begin to discriminate between competing hypotheses using a combination of experimental, natural population, bioinformatic and theoretical approaches.


Asunto(s)
Núcleo Celular/genética , Orgánulos/genética , Técnicas de Transferencia de Gen
7.
Am J Trop Med Hyg ; 39(4): 343-52, 1988 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2903689

RESUMEN

Histopathological preparations of cecum and colon from monkeys naturally infected with invasive Entamoeba histolytica were examined to determine the distribution of amebae in the tissues and the types of lesions, if any, associated with them. Infections were studied in 3 New World species (10 Callicebus moloch, 1 C. torquatus, and 2 Aotus trivirgatus) and 3 Old World species (8 Macaca mulatta, 6 Erythrocebus patas, and 1 Cercopithecus aethiops). Amebiasis was recorded as the principal or a contributing cause of death of all of the 13 New World monkeys and in 6 of the 15 Old World monkeys; amebiasis was detected in the rest of the monkeys only after tissues were re-examined specifically for amebae. Amebae causing no apparent damage were found in the lamina propriae, mainly at the muscularis mucosae. Most frequent were colonies or aggregates of amebae in the crypts between the epithelium and basement membrane, causing either no evident necrosis or changes ranging from necrosis and disarrangement of adjacent cells to complete destruction of the epithelium and reduction of the cells to pyknotic bodies. A lesion interpreted as possibly characteristic of carrier-state invasive amebiasis was destruction of the epithelium in patches of mucosal crypts, not leading to ulceration. Uncommon but present in both New and Old World monkeys were typical areas of surface erosion and classical flask-shaped ulcers. The observations show that in some species of Old World monkeys amebiasis can be invasive without causing clinical disease.


Asunto(s)
Amebiasis/veterinaria , Cebidae/parasitología , Cercopithecidae/parasitología , Entamoeba histolytica/fisiología , Entamebiasis/veterinaria , Enfermedades de los Monos/parasitología , Animales , Membrana Basal/parasitología , Ciego/parasitología , Colon/parasitología , Entamoeba histolytica/ultraestructura , Entamebiasis/epidemiología , Entamebiasis/parasitología , Epitelio/parasitología , Femenino , Mucosa Intestinal/parasitología , Masculino , Enfermedades de los Monos/epidemiología
8.
Am J Trop Med Hyg ; 49(6): 763-71, 1993 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8279642

RESUMEN

To better define Loa loa infection in the rhesus monkey and assess the potential usefulness of this host as a model for studies of human loiasis, 12 monkeys (four splenectomized and eight nonsplenectomized) were inoculated with L. loa infective larvae. Microfilaremia and hematologic changes as well as parasite-specific antibody were assessed as a function of time in these animals. Eleven of 12 inoculated monkeys became microfilaremic. Splenectomized animals had moderate (250-1,000) to low (< 250) numbers of microfilariae per milliliter (mf/ml), whereas the mf/ml in nonsplenectomized animals varied from high (> 1,000) to low. A significant increase in total leukocyte and lymphocyte numbers was seen in animals with moderate-to-low mf/ml but not in animals with high mf/ml mainly because of variations between animals in the latter group, rather than a direct consequence of increased mf numbers. All infected animals developed an eosinophilia before patency, suggesting the adult worms most likely contribute to this phenomenon. As the infection progressed, the eosinophil numbers decreased significantly. Although splenectomized animals overall had slightly higher numbers of total leukocytes (lymphocytes and eosinophils), these hematologic changes as a function of time were not significantly different from those in nonsplenectomized animals. Parasite-specific IgG antibody was increased significantly before patency in all animals and with the exception of the one amicrofilaremic animal, it decreased after patency. This study shows that splenectomy of rhesus monkeys prior to L. loa inoculation does not enhance the microfilarial density nor does it adversely affect eosinophilia or antibody production.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Modelos Animales de Enfermedad , Loa/inmunología , Loiasis/parasitología , Macaca mulatta/parasitología , Animales , Anticuerpos Antihelmínticos/sangre , Ensayo de Inmunoadsorción Enzimática , Eosinófilos , Inmunoglobulina G/sangre , Recuento de Leucocitos , Loa/fisiología , Loiasis/sangre , Loiasis/inmunología , Linfocitos , Microfilarias/inmunología , Microfilarias/fisiología , Esplenectomía
9.
Am J Trop Med Hyg ; 37(2): 385-91, 1987 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-3310689

RESUMEN

Three African green monkeys (Cercopithecus aethiops) were inoculated intravenously and intracutaneously with Mycobacterium leprae derived from a naturally infected mangabey monkey. All developed cutaneous lesions at inoculation sites. One developed disseminated cutaneous lesions, while the cutaneous lesions in the other two regressed and eventually disappeared. The animals were examined at necropsy five years after inoculation. All three had active leprosy infection in peripheral nerves with extensive inflammation and fibrosis. The disease histologically resembled borderline-lepromatous leprosy. These findings add a new dimension to animal models of leprosy.


Asunto(s)
Modelos Animales de Enfermedad , Lepra/microbiología , Enfermedades de los Monos/microbiología , Nervios Periféricos/patología , Animales , Cercopithecidae/microbiología , Chlorocebus aethiops/microbiología , Lepra/patología , Enfermedades de los Monos/patología , Mycobacterium leprae
10.
Lepr Rev ; 66(2): 105-25, 1995 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7637522

RESUMEN

In this study, 11 SMM were grouped and inoculated with differing doses of SMM-origin Mycobacterium leprae (ML) between 4.5 x 10(8) and 1 x 10(9) by either combined IV/IC routes or by IV or IC route alone. The combined route was the most effective in eliciting progressive, disseminated LL leprosy. In all, 6 of 7 SMM inoculated by the combined routes developed leprosy requiring treatment at some point. Only 1 of 4 inoculated by a single route developed persisting leprosy requiring chemotherapy. Either no disease or spontaneous regression of initial disease occurred in the other 3 animals inoculated by a single route. Doses in excess of 1 x 10(9) ML were more effective than lesser doses. An association was observed between the development of IgG anti-PGL-I ELISA OD values and resistance to leprosy and between IgM anti-PGL-I and leprosy progression or susceptibility. Serum PGL-I antigen levels, determined by dot ELISA, paralleled disease severity longitudinally. High positive OD values of anti-LAM IgG prior to ML inoculation were observed in the majority of leprosy-susceptible SMM in contrast to negative levels in more resistant animals. Anti-LAM IgG OD values exceeded the positive cut-off point after inoculation in 5 of 11 SMM; 3 of these 5 had concurrent detectable serum levels of PGL-I antigen.


Asunto(s)
Antígenos Bacterianos/análisis , Glucolípidos/análisis , Lepra/inmunología , Lipopolisacáridos/análisis , Mycobacterium leprae/inmunología , Animales , Cercocebus atys , Modelos Animales de Enfermedad , Ensayo de Inmunoadsorción Enzimática , Inmunoglobulina G/análisis , Inmunoglobulina M/análisis , Estudios Longitudinales
11.
Lepr Rev ; 66(2): 96-104, 1995 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7637533

RESUMEN

A total of 31 sooty mangabey monkeys (SMM) (Cercocebus torquatus atys) inoculated by various routes with differing numbers of SMM-origin Mycobacterium leprae (ML) and 4 SMM inoculated with human-origin ML were observed for 4-12 years. SMM-origin ML was more pathogenic in SMM than human-origin ML. The spectrum of disease ranged from indeterminate to borderline and lepromatous in different animals. Some animals developed pure neural leprosy. Erythema nodosum leprosum (SNL) was also observed. Combined intravenous/intracutaneous (IV/IC) routes of inoculation more effectively induced advancing, disseminated lepromatous forms of leprosy; IV or IC routes alone were less effective at comparable doses. Total IV/IC doses of SMM-origin ML equal to or greater than 5 x 10(8), with morphologic indices (MIs) ranging from 5 to 10%, produced advancing, disseminated LL leprosy in 92% of SMM. Lower IV/IC doses and inoculations by a single IV or IC route produced fewer leprosy infections and more spontaneous regressions. As a species, captive SMM are highly susceptible to experimental leprosy and provide an excellent model for the longitudinal study of leprosy.


Asunto(s)
Modelos Animales de Enfermedad , Lepra , Animales , Cercocebus atys , Susceptibilidad a Enfermedades , Lepra/patología , Lepra/fisiopatología , Lepra/transmisión , Estudios Longitudinales
12.
Lepr Rev ; 69(3): 235-45, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9805879

RESUMEN

A total of 46 Rhesus monkeys (RM) was inoculated with Mycobacterium leprae (ML) and followed clinically and immunologically for extended periods. Twenty-one (45.7%) of the RM developed leprosy spanning the known leprosy spectrum, with six of 21 (28.6%) having disease in the borderline lepromatous to lepromatous area of the spectrum. RM with paucibacillary forms of leprosy produced predominantly IgG anti-phenolic glycolipid (PGL-I) antibodies and positive lepromin skin test and/or in vitro blastogenesis responses; IgM anti-PGL-I predominated in animals with BB-LL leprosy and correlated with negative immune responses to lepromin. IgG anti-PGL-I antibodies persisted in a number of RM for several years without histopathological evidence of leprosy, suggesting possible persisting subclinical infection. The data show that RM are a valuable model for the study of leprosy. Eleven of the 46 RM were inoculated with ML from sources infected with simian immunodeficiency virus (SIV), the monkey counterpart to the human immunodeficiency virus (HIV). The possible effect of SIV on the clinical outcome of ML infection could not be determined due to insufficient numbers of animals to yield statistically significant results.


Asunto(s)
Anticuerpos Antibacterianos/análisis , Lepra/inmunología , Lepra/transmisión , Mycobacterium leprae/inmunología , Animales , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades , Ensayo de Inmunoadsorción Enzimática , Macaca mulatta , Sensibilidad y Especificidad , Pruebas Cutáneas
13.
J Comp Pathol ; 99(1): 109-13, 1988 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-3209757

RESUMEN

In an adult male rhesus monkey, a large pelvic mass causing lysis of the ilium and destruction of pelvic musculature was diagnosed as a spontaneous rhabdomyosarcoma by the use of histological, ultrastructural and immunohistochemical techniques.


Asunto(s)
Macaca mulatta , Macaca , Enfermedades de los Monos/diagnóstico , Neoplasias de Tejido Muscular/veterinaria , Rabdomiosarcoma/veterinaria , Animales , Inmunohistoquímica , Masculino , Enfermedades de los Monos/patología , Neoplasias de Tejido Muscular/diagnóstico , Neoplasias de Tejido Muscular/patología , Neoplasias de Tejido Muscular/ultraestructura , Rabdomiosarcoma/diagnóstico , Rabdomiosarcoma/patología , Rabdomiosarcoma/ultraestructura
14.
Am J Vet Res ; 46(10): 2136-40, 1985 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-4062019

RESUMEN

Two experiments were performed to determine whether previous infection of young lambs with Ostertagia circumcincta increased their resistance to the development of Haemonchus contortus and to explore alterations in the microenvironment of the abomasum related to the interaction. The parasitic infections were monitored with periodic fecal egg counts and by recovery and enumeration of parasites at necropsy of the lambs. Alteration of the microenvironment was examined by measurement of serum gastrin concentrations at critical times during both experiments. The results indicated that the numbers of H contortus were significantly (P less than 0.05) less in lambs which had O circumcincta infections before their exposure to H contortus. There was less reduction in lambs from which O circumcincta was removed (anthelmintic therapy) before their exposure to H contortus. Fecal egg counts also were significantly (P less than 0.05) less in the former group of lambs (exposed to both parasites) than those in lambs exposed only to H contortus. Serum gastrin values were significantly (P less than 0.05) increased in lambs infected with O circumcincta and indicated that the interaction observed could be due, in part, to alteration of abomasal pH.


Asunto(s)
Hemoncosis/veterinaria , Ostertagiasis/veterinaria , Enfermedades de las Ovejas/parasitología , Tricostrongiloidiasis/veterinaria , Animales , Susceptibilidad a Enfermedades/parasitología , Susceptibilidad a Enfermedades/veterinaria , Femenino , Hemoncosis/parasitología , Masculino , Ostertagiasis/parasitología , Recuento de Huevos de Parásitos , Ovinos
15.
Am J Vet Res ; 47(2): 309-14, 1986 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-3954209

RESUMEN

Two experiments were done to examine the severity and type of abomasal lesions induced by moderate infections of Ostertagia circumcincta in young lambs and to examine the differences in pathologic changes in lambs with monospecific and combined infections of O circumcincta and Haemonchus contortus. Observations included descriptions of gross and microscopic changes in the abomasums, as well as quantitative analysis of the thickness of the mucosa, numbers of mucus-containing cells, and inflammatory cell accumulations. Seemingly, the changes in the abomasal mucosa of lambs inoculated with O circumcincta were mild and included dilated glands, focal accumulations of lymphocytes, and significant (P less than 0.05) numerical increases of mucus-containing cells, eosinophils, and globule leukocytes, and increase of mucosal thickness when compared with those in noninoculated controls. These differences were less pronounced in lambs given anthelmintic treatment to remove O circumcincta. When H contortus infections were superimposed upon O circumcincta infection, the changes were essentially the same as those described for O circumcincta plus a small, but significant (P less than 0.05), numerical increase of globule leukocytes. Abomasal mucosa of lambs inoculated only with H contortus was more roughened and hyperemic than that of lambs with combined infections, but contained few dilated glands and globule leukocytes. Our conclusions were that moderate infection with O circumcincta did not cause severe or permanent damage to the abomasal mucosa and that such infection decreased the severity of the gross lesions produced by H contortus.


Asunto(s)
Hemoncosis/patología , Hemoncosis/veterinaria , Ostertagiasis/veterinaria , Enfermedades de las Ovejas/patología , Tricostrongiloidiasis/patología , Tricostrongiloidiasis/veterinaria , Abomaso/patología , Animales , Femenino , Hemoncosis/complicaciones , Masculino , Membrana Mucosa/patología , Ostertagiasis/complicaciones , Ostertagiasis/patología , Ovinos
16.
Contemp Top Lab Anim Sci ; 39(6): 24-6, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11487248

RESUMEN

To support an infectious disease study, we developed a surgical procedure to collect serial thymic biopsies in rhesus monkeys (Macaca mulatta). In many instances in which thymic tissue is required from living animals, open surgical approaches (thoracotomies) are used, which result in greater postoperative pain and longer recovery periods than those associated with thoracoscopic procedures. Our intent was to develop a surgical procedure that allowed serial biopsy of the thymus with minimal surgical morbidity. We modified a previously published experimental method of thoracoscopic total thymectomy in the dog to collect thymic biopsies in M. mulatta. Of the 15 animals evaluated, 8 underwent two biopsy procedures separated by a 5- to 6-week interoperative interval. The other seven animals underwent a single biopsy procedure. Thymic tissue was collected successfully during all procedures, with an average surgical time of 15 min. No significant intra- or postoperative complications were noted, and the animals recoveries from the surgical procedures were uneventful. Minimally invasive thoracoscopic surgical techniques can be used successfully to collect thymic tissue from adult and juvenile rhesus monkeys with minimal surgical morbidity.


Asunto(s)
Cirugía Torácica Asistida por Video/veterinaria , Timo/patología , Animales , Biopsia/métodos , Biopsia/veterinaria , Femenino , Macaca mulatta , Masculino , Morbilidad , Dolor Postoperatorio/prevención & control , Dolor Postoperatorio/veterinaria , Cirugía Torácica Asistida por Video/métodos
18.
Genetica ; 102-103(1-6): 29-39, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9720269

RESUMEN

It is well established on theoretical grounds that the accumulation of mildly deleterious mutations in nonrecombining genomes is a major extinction risk in obligately asexual populations. Sexual populations can also incur mutational deterioration in genomic regions that experience little or no recombination, i.e., autosomal regions near centromeres, Y chromosomes, and organelle genomes. Our results suggest, for a wide array of genes (transfer RNAs, ribosomal RNAs, and proteins) in a diverse collection of species (animals, plants, and fungi), an almost universal increase in the fixation probabilities of mildly deleterious mutations arising in mitochondrial and chloroplast genomes relative to those arising in the recombining nuclear genome. This enhanced width of the selective sieve in organelle genomes does not appear to be a consequence of relaxed selection, but can be explained by the decline in the efficiency of selection that results from the reduction of effective population size induced by uniparental inheritance. Because of the very low mutation rates of organelle genomes (on the order of 10(-4) per genome per year), the reduction in fitness resulting from mutation accumulation in such genomes is a very long-term process, not likely to imperil many species on time scales of less than a million years, but perhaps playing some role in phylogenetic lineage sorting on time scales of 10 to 100 million years.


Asunto(s)
Modelos Genéticos , Mutación , Orgánulos/genética , Saccharomyces cerevisiae/genética , Schizosaccharomyces/genética , Animales , Femenino , Masculino , Mitocondrias/genética , Modelos Estadísticos , Plantas/genética , ARN Ribosómico/genética , Recombinación Genética , Cromosoma Y
19.
Phlebologie ; 41(3): 509-25, 1988.
Artículo en Francés | MEDLINE | ID: mdl-3222295

RESUMEN

Obesity modifies the tissular anatomy and the mechanical characteristics of the limb. Because of this, there are difficulties in the interpretation of results produced by techniques designed to explore the venous functioning of the limbs. Our work has two main objectives. First of all a retrospective study shows that venous plethysmography is comparably sensitive in the obese patient with regard to the diagnosis of phlebitis (90% in the obese patient; 95% in the non-obese). As regards specific detail, however, it is not as good in the case of the obese patient (88.7% against 97.5%). Another, prospective, study on the normal, that is non-varicose, subject (obese and non-obese), enables us to analyse parameters modified by obesity, certain false positives in venous distensibility.


Asunto(s)
Obesidad/complicaciones , Tromboflebitis/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pletismografía , Tromboflebitis/complicaciones
20.
J Mol Evol ; 41(4): 397-406, 1995 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7563126

RESUMEN

A surprisingly large number of plant nuclear DNA sequences inferred to be remnants of chloroplast and mitochondrial DNA migration events were detected through computer-assisted database searches. Nineteen independent organellar DNA insertions, with a median size of 117 bp (range of 38 to > 785 bp), occur in the proximity of 15 nuclear genes. One fragment appears to have been passed through a RNA intermediate, based on the presence of an edited version of the mitochondrial gene in the nucleus. Tandemly arranged fragments from disparate regions of organellar genomes and from different organellar genomes indicate that the fragments joined together from an intracellular pool of RNA and/or DNA before they integrated into the nuclear genome. Comparisons of integrated sequences to genes lacking the insertions, as well as the occurrence of coligated fragments, support a model of random integration by end joining. All transferred sequences were found in noncoding regions, but the positioning of organellar-derived DNA in introns, as well as regions 5' and 3' to nuclear genes, suggests that the random integration of organellar DNA has the potential to influence gene expression patterns. A semiquantitative estimate was performed on the amount of organellar DNA being transferred and assimilated into the nucleus. Based on this database survey, we estimate that 3-7% of the plant nuclear genomic sequence files contain organellar-derived DNA. The timing and the magnitude of genetic flux to the nuclear genome suggest that random integration is a substantial and ongoing process for creating sequence variation.


Asunto(s)
Núcleo Celular/metabolismo , ADN de Plantas/metabolismo , Orgánulos/metabolismo , Plantas/metabolismo , Secuencia de Bases , Cloroplastos/metabolismo , ADN Mitocondrial/química , ADN Mitocondrial/metabolismo , ADN de Plantas/química , Mitocondrias/metabolismo , Datos de Secuencia Molecular , Homología de Secuencia de Ácido Nucleico , Especificidad de la Especie
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