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1.
J Evol Biol ; 25(7): 1264-74, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22537030

RESUMO

Reproduction entails costs, and disentangling the relative importance of each stage of the reproductive cycle may be important to assess the costs and benefits of different reproductive strategies. We studied the early costs of reproduction in oviparous and viviparous lizard females of the bimodal reproductive species Zootoca vivipara. Egg retention time in oviparous females is approximately one-third of the time in viviparous females. We compared the vitellogenesis and egg retention stages that are common to both reproductive modes. Precisely, we monitored the thermoregulatory behaviour, the weight gain and the immunocompetence of the females. Moreover, we injected an antigen in half of the females (immune challenge) to study the trade-offs between reproductive mode and immune performance and between different components of the immune system. Finally, we experimentally induced parturition in viviparous females at the time of egg laying in oviparous females. Oviparous and viviparous females did not show strong differences in response to the immune challenge. However, viviparous females spent more time thermoregulating while partially hidden and gained more weight than oviparous females. The greater weight gain indicates that the initial period of egg retention is less costly for viviparous than for oviparous females or that viviparous females are able to save and accumulate energy at this period. This energy may be used by viviparous females to cope with the subsequent costs of the last two-third of the gestation. Such an ability to compensate the higher costs of a longer egg retention period may account for the frequent evolution of viviparity in squamate reptiles.


Assuntos
Lagartos/fisiologia , Oviparidade , Viviparidade não Mamífera , Animais , Tamanho Corporal , Temperatura Corporal , Feminino , Reprodução
2.
J Fr Ophtalmol ; 44(7): 947-956, 2021 Sep.
Artigo em Francês | MEDLINE | ID: mdl-34148703

RESUMO

INTRODUCTION: The Ambulatory Clinic for Cataract Surgery (CACC) is a public department of the Bourges Medical Center, with a fast-track protocol without perioperative anesthesia care launched in 2015. This study aimed to evaluate the benefits of the CACC in terms of access to cataract surgery. METHODS: This retrospective study included all patients undergoing cataract surgery between 2012 and 2018. Data were collected from the French PMSI database. In order to evaluate the impact of the CACC, the surgical activity and change in indicators of patient flow and usage, as well as clinical and economic factors were analyzed. RESULTS: Between 2012 and 2018, with the same number of ophthalmologists, surgical activity increased by 50.2% in the Cher (vs. a mean increase of 22.7% in France). The patient loss ratio decreased by 5.9 points, the attraction and self-sufficiency ratios increased by 2.3 and 8.6 points respectively. The standardized rate of healthcare utilization for cataract surgery increased by 4.3 points (from 11.6 to 15.9 surgeries per 1000 inhabitants). As a result, Cher became the second highest French Department in 2018 in terms of utilization rate despite its 96th place out of 109 Departments in terms of density of ophthalmologists. CONCLUSION: The ambulatory cataract surgery center without anesthesia for selected patients might represent a solution in medical deserts to improve access to cataract surgery without increasing costs.


Assuntos
Anestesia , Anestesiologia , Extração de Catarata , Catarata , Procedimentos Cirúrgicos Ambulatórios , Catarata/epidemiologia , Humanos , Estudos Retrospectivos
3.
J Fr Ophtalmol ; 44(6): 813-821, 2021 Jun.
Artigo em Francês | MEDLINE | ID: mdl-33965273

RESUMO

OBJECTIVE: This study aimed to analyse the epidemiological characteristics of ophthalmological emergencies at the Bourges Medical Center (CHB) and to identify factors associated with severity according to the Base Score in a region of France considered a healthcare desert. METHODS: All consecutive charts of patients seen for an eye-related condition between January 1 and April 30, 2019 in the ocular emergency department of the CHB were studied retrospectively. Seven demographic and nine medical variables were collected, and ocular severity was defined according to the Base Score. Linear regressions were performed to identify the factors associated with higher severity. RESULTS: 1809 patients were included (mean age: 53.3±22.7 years, 51.4% women), of whom 1619 (89.5%) were self-referred. Ocular surface disease (12.5%) was the most frequent diagnosis. The severity of the eye-related condition was significantly associated with the following factors: male gender, distance from home to the emergency department, presentation soon after the onset of symptoms, and referral from a physician (ophthalmologist or not). The regression coefficient was greater than 1 only for the patient referral pattern. CONCLUSION: The current study highlights that when patients with ocular emergencies can self-refer to an ocular emergency department within a French healthcare desert, 9 patients out of 10 self-refer. Referral from a physician is the main factor associated with ocular severity; thus, these cases should be considered severe until proven otherwise.


Assuntos
Emergências , Serviço Hospitalar de Emergência , Adulto , Idoso , Feminino , França , Hospitais , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
4.
Evolution ; 55(2): 392-404, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11308095

RESUMO

Correlation between intraspecific phenotypic variability and variation of environmental conditions could reflect adaptation. Different phenotypes may result from differential expression of a genotype in different environments (phenotypic plasticity) or from expression of different genotypes (genetic diversity). Populations of Lacerta vivipara exhibit larger adult body length, lower age at maturity, higher fecundity, and smaller neonatal size in humid habitats compared to dry habitats. We conducted reciprocal transplants of juvenile L. vivipara to test for the genetic or plastic origin of this variation. We captured gravid females from four populations that differed in the relative humidity of their habitats, and during the last 2 to 4 weeks of gestation, we manipulated heat and water availability under laboratory conditions. Juveniles were released into the different populations and families were divided to compare growth rate and survival of half-sibs in two environments. Growth rate and survival were assessed using capture-recapture techniques. Growth rate was plastic in response to postnatal conditions and did not differ between populations of origin. Survival differed between populations of origin, partially because of differences in neonatal body length. The response of juvenile body length and body condition to selection in the different habitats was affected by the population of origin. This result cannot be simply interpreted in terms of adaptation; however, phenotypic plasticity of fecundity or juvenile size most probably resulted in adaptive reproductive strategies. Adaptation to the habitat by means of genetic specialization was not detected. Further investigation is needed to discriminate between genetic and long-term maternal effects.


Assuntos
Adaptação Fisiológica , Lagartos/fisiologia , Fenótipo , Animais , Meio Ambiente , Feminino , Fertilidade , Variação Genética , Lagartos/genética , Longevidade , Masculino , Gravidez
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 60(3): 689-700, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14747095

RESUMO

Raman scattering (RS) and Fourier transform-infrared (FT-IR) spectroscopy have been applied to the structural characterisation of manganese dioxides (MDOs). A variety of synthetic battery-grade MDOs are investigated for comparison to the natural phases. The RS and FT-IR spectra are analysed on the basis of the local environment in the MDO structures considering the vibrations of the MnO6 octahedral building the lattices. The vibrational modes of the MnO6 units expand over 400-650 cm(-l) with additional bands in the low-wavelength region. Structural trends are deduced from the comparison of the vibrational spectra of the MDO phases investigated: birnessite, bixbyite, coronadite, groutite, hausmannite, hollandite, manganosite, pyrolusite, ramsdellite, romanechite, spinel, and todorokite.


Assuntos
Compostos de Manganês/química , Óxidos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Difração de Raios X
6.
Phys Rev B Condens Matter ; 39(11): 7585-7589, 1989 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-9947438
8.
J Evol Biol ; 20(1): 221-32, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17210015

RESUMO

Within-sex colour variation is a widespread phenomenon in animals that often plays a role in social selection. In males, colour variation is typically associated with the existence of alternative reproductive strategies. Despite ecological conditions theoretically favourable to the emergence of such alternative strategies in females, the social significance of colour variation in females has less commonly been addressed, relative to the attention given to male strategies. In a population of the common lizard, females display three classes of ventral colouration: pale yellow, orange and mixed. These ventral colours are stable through individual's life and maternally heritable. Females of different ventral colourations displayed different responses of clutch size, clutch hatching success and clutch sex-ratio to several individual and environmental parameters. Such reaction patterns might reflect alternative reproductive strategies in females. Spatial heterogeneity and presence of density- and frequency-dependent feedbacks in the environment could allow for the emergence of such alternative strategies in this population and the maintenance of colour variation in females.


Assuntos
Meio Ambiente , Lagartos/fisiologia , Pigmentação/fisiologia , Reprodução/fisiologia , Seleção Genética , Animais , Pesos e Medidas Corporais , Feminino , França , Lagartos/anatomia & histologia , Densidade Demográfica , Razão de Masculinidade , Espectrofotometria , Análise de Sobrevida
9.
J Evol Biol ; 19(3): 690-704, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16674566

RESUMO

To elucidate the developmental aspects of the evolution of sexual size dimorphism (SSD), an understanding of the sex-specific ontogeny of body size is critical. Here, we evaluate the relative importance of genetic and environmental determinants of SSD in juvenile common lizards (Lacerta vivipara). We examined the prenatal and post-natal effects of population density and habitat humidity on SSD, as well as the maternal effects of food availability, corticosterone level, humidity and heat regime during gestation. Analyses indicated strong prenatal and post-natal plasticity in body size per se and yielded three main results with respect to SSD. First, SSD in juvenile common lizards matches qualitatively the SSD observed in adults. Secondly, SSD was influenced by none of the prenatal factors investigated here, suggesting poor sex-biased maternal effects on offspring size. Thirdly, SSD was sensitive to post-natal habitat humidity, which positively affected growth rate more strongly in females than in males. Thus, natural variation in SSD in juvenile common lizards appears to be primarily determined by a combination of sex-biased genetic factors and post-natal conditions. We discuss the possibility that viviparity may constrain the evolution of sex-biased maternal effects on offspring size.


Assuntos
Variação Genética , Lagartos/anatomia & histologia , Lagartos/fisiologia , Animais , Evolução Biológica , Tamanho Corporal , Meio Ambiente , Feminino , Lagartos/crescimento & desenvolvimento , Masculino , Caracteres Sexuais
10.
J Evol Biol ; 18(6): 1455-63, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16313458

RESUMO

Sex allocation theory predicts that facultative maternal investment in the rare sex should be favoured by natural selection when breeders experience predictable variation in adult sex ratios (ASRs). We found significant spatial and predictable interannual changes in local ASRs within a natural population of the common lizard where the mean ASR is female-biased, thus validating the key assumptions of adaptive sex ratio models. We tested for facultative maternal investment in the rare sex during and after an experimental perturbation of the ASR by creating populations with female-biased or male-biased ASR. Mothers did not adjust their clutch sex ratio during or after the ASR perturbation, but produced sons with a higher body condition in male-biased populations. However, this differential sex allocation did not result in growth or survival differences in offspring. Our results thus contradict the predictions of adaptive models and challenge the idea that facultative investment in the rare sex might be a mechanism regulating the population sex ratio.


Assuntos
Comportamento Materno/fisiologia , Modelos Biológicos , Seleção Genética , Razão de Masculinidade , Animais , Constituição Corporal/fisiologia , Pesos e Medidas Corporais , Tamanho da Ninhada/fisiologia , Feminino , Lagartos , Cauda/anatomia & histologia
11.
Proc Natl Acad Sci U S A ; 95(2): 600-5, 1998 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-9435238

RESUMO

The potential existence of natal dispersal strategies depending on parental age has been suggested by Hamilton and May [Hamilton, W. D. & May, R. M. (1977) Nature 269, 578-581] for organisms whose survival rates decline with age. When competition between parent and offspring is strong, any individual should disperse a smaller fraction of its offspring when it ages. Here, we verify their verbal prediction. First, we determine the evolutionarily stable dispersal strategy conditional on parental age, associated with a particular senescence curve. We show that such a conditional dispersal strategy should evolve independently from the genotype controlling the offspring dispersal behavior. Second, studying a population of common lizards, we provide empirical evidence of a relation between dispersal of female offspring and maternal senescence, in agreement with our theoretical predictions.


Assuntos
Envelhecimento , Genética Populacional , Modelos Biológicos , Modelos Teóricos , Animais , Feminino , Humanos , Masculino
12.
Sangre (Barc) ; 44(6): 412-7, 1999 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-10822752

RESUMO

OBJECTIVE: Neoantigen formation during heat treatment (HT) of factor VIII:von Willebrand Factor (FVIII:vWF) concentrates may induce an immune response against the modified protein, which may also affect the native protein. We present a comparative in vitro study on the immunogenicity of a dual virally inactivated (solvent-detergent and 80 degrees C 72 hours) high purity FVIII:vWF concentrate (Fanhdi) versus the same product without heat treatment. MATERIAL AND METHODS: For this purpose rabbit antisera were prepared using both Fanhdi and the same product from which the human albumin, used as stabilizer, had been removed (these were both HT products). Also, antisera were prepared against the same products made without the dry-heat treatment step (non-HT products). Antisera were analysed by Elisa. Mixtures of antisera with increasing amounts of product (incubation-absorption in liquid phase) were assayed in plates coated with HT and non-HT products. RESULTS: The binding of antibodies against HT products to ELISA plates coated with HT products, could be blocked (in a saturable manner) with non-HT products, following liquid phase incubation. These results strongly suggest the absence of neonantigens. Furthermore, the binding of antibodies against non-HT products to ELISA plates coated with non-HT products, could be blocked (also in a saturable manner) with HT products. This result indicates that there is no epitope loss. CONCLUSIONS: The data obtained in these studies suggest that the heat treatment of viral inactivation as applied in Fanhdi, does not give rise to any major alteration in immunogenicity of the product. The data from clinical and drug surveillance studies carried out with Fanhdi do not show any indication of an increase in the frequency of inhibitors.


Assuntos
Ensaio de Imunoadsorção Enzimática , Fator VIII/análise , Fator de von Willebrand/análise , Animais , Temperatura Alta , Humanos , Soros Imunes , Coelhos
13.
Mol Ecol ; 13(3): 719-23, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14871374

RESUMO

The common lizard (Lacerta vivipara) is a small live-bearing lacertid that reproduces once a year. In order to document the poorly known mating system of this species, we present here an assessment of multiple paternity using microsatellite markers. Paternities were established within 122 clutches belonging to two wild populations from contrasted areas and to four seminatural enclosed populations. The proportion of multiply sired clutches was found to be very high (between 50.0% and 68.2%) and similar among populations, which suggests that the mating system of this species may be insensitive to environmental and population conditions.


Assuntos
Lagartos/genética , Reprodução/fisiologia , Comportamento Sexual Animal , Animais , Pai , França , Tamanho da Ninhada de Vivíparos/genética , Lagartos/fisiologia , Masculino , Repetições de Microssatélites/genética
14.
Haematologica ; 83(4): 305-11, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9592979

RESUMO

BACKGROUND AND OBJECTIVE: Antithrombin III (ATIII) concentrates are employed as therapy for congenital or acquired deficiencies. These concentrates are obtained from Cohn's fraction IV1. To improve yields, purity and safety, our group developed a procedure to obtain a pasteurized ATIII concentrate from the supernatant of Cohn's fraction II + III including a highly efficient heparin affinity chromatography purification and pasteurization as a viral inactivation step. DESIGN AND METHODS: Three steps of the manufacturing procedure (Cohn's fraction II + III precipitation, affinity chromatography and pasteurization) were selected to examine their efficacy in inactivating and/or removing the selected viruses. RESULTS: The industrial batches show a purity higher than 99% with approximately 95% native heparin binding ATIII. Only albumin and IgG could be detected at trace levels (0.07% and 0.16% of the total protein present, respectively). The specific activity of the product was approximately 6.65 IU/mg protein. Five viruses were spiked into the manufacturing starting materials and samples were collected at various points to determine the infection level of virus. The study showed a reduction factor (log 10) > or = 11.7 for HIV-1; > or = 8.1 for bovine herpes virus (analyzed as a model for herpes and hepatitis B viruses); > or = 8.1 for bovine diarrhea virus (model for hepatitis C and G) and > or = 6.0 for encephalomyocarditis virus (model for hepatitis A and other non-enveloped viruses). INTERPRETATION AND CONCLUSIONS: No biochemical alterations of the ATIII were detected in the final product. A high viral elimination capacity of the production process was demonstrated. So far, more than 32 million units of ATIII have been transfused in the form of this therapeutic concentrate without any detected seroconversion.


Assuntos
Antitrombina III/isolamento & purificação , Cromatografia de Afinidade/métodos , Viroses/prevenção & controle , Antitrombina III/uso terapêutico , Estudos de Avaliação como Assunto , Humanos , Segurança , Esterilização/normas , Viroses/sangue
15.
Sangre (Barc) ; 41(2): 125-30, 1996 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-9045352

RESUMO

AIM: To develop a therapeutic human high purity FVIII concentrate, treated with two documented and complementary specific inactivation methods, for the treatment of haemophilia A. MATERIAL AND METHODS: Cryoprecipitate was obtained from human plasma, normal for ALT levels and negative for HBsAg and antibodies to HIV and to HCV. The cryoprecipitate was resuspended and purified with PEG. The PEG precipitate was resuspended and treated with TNBP/Polysorbate 80. The mixture was processed by heparin affinity chromatography. The eluate was concentrated and precipitated with glycine and salts. After resuspension, stabilizers were added and the solution was sterile filtered, dispensed in vials and lyophilized. These final vials were treated at 80 degrees C for 72 hours: FVIII:C, vWF:RCo, vWF:Ag, vWF multimeric structure and the concentration of other plasmatic proteins were analyzed. RESULTS: FVIII: C specific activity was between 1000 and 3000 U/mg (after elimination of vWF, present as a stabilizer and before the addition of human pasteurized albumin). vWF:RCo activity (0.7 U vWF:RCo/U FVIII:C) and the multimeric structure of vWF showed a good degree of conservation. Other plasmatic proteins analyzed were undetectable or at trace amounts. No prekalllikrein, kallikrein or activated coagulation factors activity could be detected. CONCLUSION: The FVIII concentrate described shows a high degree of purity and stability, which makes it very suitable for haemophilia A treatment.


Assuntos
Detergentes/farmacologia , Fator VIII/isolamento & purificação , Temperatura Alta , Organofosfatos/farmacologia , Polissorbatos/farmacologia , Solventes/farmacologia , Vírus/efeitos dos fármacos , Sangue/virologia , Coagulação Sanguínea , Proteínas Sanguíneas/análise , Precipitação Química , Cromatografia de Afinidade , Temperatura Baixa , Fator VIII/análise , Hemofilia A/terapia , Heparina/metabolismo , Humanos , Polietilenoglicóis , Vírus/isolamento & purificação
16.
Sangre (Barc) ; 41(2): 131-6, 1996 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-9045353

RESUMO

AIM: To perform a validation study of the production process of a human high purity FVIII concentrate, obtained by affinity chromatography and treated with solvent-detergent and 80 degrees C, 72- hour dry heating in the final vial, in order to demonstrate its viral safety. MATERIAL AND METHODS: The ability to inactivate or eliminate viruses was studied in the steps of PEG precipitation, solvent-detergent treatment (6 h 25 degrees C), affinity chromatography and lyophilization plus heating 80 degrees C for 72 h. HIV and models for hepatitis A, B and C, as well as a model for parvovirus B-19 were employed. The experiments were carried out by spiking the samples at each step with 10% of their volume with the highest titer available virus culture. The samples were processed under validated conditions (mimicking the industrial process) and the residual infectivity was determined (as well as p24 antigen and reverse transcriptase for HIV at the solvent-detergent step). RESULTS: No residual infectivity could be detected for enveloped viruses (HIV and models for hepatitis B and C) after the first minutes of solvent-detergent treatment, which lasts 6 hours. Lyophilization followed by heating 80 degrees C for 72 hours caused complete disappearance of infectivity for the models of hepatitis A and C, before 24 hours of a treatment which lasts 72. Furthermore, lyophilization plus heating reduced infectivity for the models of hepatitis B and parvovirus B-19 by 3.4 and 4.1 logs, respectively. The affinity chromatography reduced infectivity by 7.6 logs for the model of hepatitis B and 2 logs for HIV. PEG precipitation also reduced the infectivity by 3.3 logs for the model of hepatitis A and by 1.2 logs for the model of parvovirus B-19. Taking the process as whole, the study showed cumulative reduction values between 5.3 and > 19 logs of the analyzed viruses. 25 million FVIII units have been transfused so far as FANHDI, with no seroconversion detected. Furthermore, no increase in FVIII inhibitor frequency has been described. CONCLUSION: The FVIII concentrate described shows outstanding viral safety characteristics. These data, together with the preliminary clinical experience after one year usage of the product, indicate that FANHDI is a suitable preparation for haemophilia A treatment.


Assuntos
Detergentes/farmacologia , Fator VIII/isolamento & purificação , Temperatura Alta , Organofosfatos/farmacologia , Polissorbatos/farmacologia , Solventes/farmacologia , Viroses/prevenção & controle , Sangue/virologia , Cromatografia de Afinidade , Estudos de Avaliação como Assunto , HIV/efeitos dos fármacos , HIV/isolamento & purificação , Hemofilia A/terapia , Vírus de Hepatite/efeitos dos fármacos , Vírus de Hepatite/isolamento & purificação , Humanos , Parvovirus B19 Humano/efeitos dos fármacos , Parvovirus B19 Humano/isolamento & purificação , Segurança , Viroses/transmissão
17.
Haemophilia ; 7(4): 369-74, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11442641

RESUMO

In order to determine the difference in reactivity of factor (F) VIII inhibitors against the FVIII/von Willebrand factor (vWF) complex and against vWF-deficient FVIII, we investigated a panel of 10 antibodies to FVIII from multitransfused individuals with severe haemophilia A and other pathologies. Immunoblotting of purified FVIII and purified thrombin-cleaved FVIII revealed that in all cases inhibitor epitopes could be localized in the heavy chain (A2 subunit) while in four cases they were also present in the light chain. One of the FVIII inhibitors remained unclassified. The effect on FVIII:C of purified IgG from inhibitor plasmas was tested against a high purity FVIII/vWF concentrate and a monoclonally purified FVIII concentrate with only trace contents of vWF, by two different functional assays. Our results suggest that for those inhibitors showing A2 plus light chain (LC) reactivity, the IgG concentration required to inhibit 50% of FVIII activity in vitro is higher for the FVIII/vWF complex than for the vWF-deficient FVIII. We conclude that there might be a protective role of vWF (at least in vitro) against FVIII inhibitors with A2 and LC subunit specificity.


Assuntos
Anticorpos/imunologia , Fator VIII/imunologia , Hemofilia A/imunologia , Fator de von Willebrand/imunologia , Anticorpos/sangue , Especificidade de Anticorpos , Reações Antígeno-Anticorpo , Fator VIII/uso terapêutico , Hemofilia A/sangue , Hemofilia A/tratamento farmacológico , Humanos
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