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1.
J Evol Biol ; 23(12): 2694-708, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20939859

RESUMEN

Mating isolation is a frequent contributor to ecological speciation - but how consistently does it evolve as a result of divergent selection? We tested for genetically based mating isolation between lake and stream threespine stickleback (Gasterosteus aculeatus L.) from the Misty watershed, Vancouver Island, British Columbia. We combined several design elements that are uncommon in the studies of stickleback mate choice: (i) we used second-generation laboratory-reared fish (to reduce environmental and maternal effects), (ii) we allowed for male-male competitive interactions (instead of the typical no-choice trials) and (iii) we included hybrids along with pure types. Males of different types (Lake, Inlet, hybrid) were paired in aquaria, allowed to build nests and then exposed sequentially to females of all three types. We found that Lake and Inlet males differed in behaviours thought to influence stickleback mate choice (inter- and intra-sexual aggression, display and nest activities), whereas hybrids were either intermediate or apparently 'inferior' in these behaviours. Despite these differences, Lake and Inlet fish did not mate assortatively and hybrid males did not have a mating disadvantage. Our study reinforces the noninevitability of mating isolation evolving in response to ecological differences and highlights the need to further investigate the factors promoting and constraining progress towards ecological speciation.


Asunto(s)
Hibridación Genética , Preferencia en el Apareamiento Animal , Smegmamorpha/fisiología , Aislamiento Social , Animales , Conducta Competitiva , Femenino , Masculino , Selección Genética
2.
J Rheumatol ; 28(10): 2245-51, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11669164

RESUMEN

OBJECTIVE: To describe the prevalence and clinical and laboratory characteristics of sicca syndrome and Sjögren's syndrome (SS) in chronic hepatitis C virus (HCV) infection. METHODS: Forty-five consecutive HCV infected patients referred for liver biopsy were enrolled in a prospective study. Subjective and objective criteria of xerophthalmia or xerostomia were systematically investigated and the patients classified according to 3 sets of criteria (European, Manthorpe, and Fox criteria) for the diagnosis of SS. RESULTS: Sicca syndrome was present in 28 (62%) patients; all had oral dryness and 14 had both oral and ocular dryness. Twenty-four (53%) patients had SS by the European criteria, 25 (56%) by Manthorpe criteria, and 4 (8%) by Fox criteria. Salivary gland biopsy was positive for SS (grade III or IV by Chishom classification) in 21 samples (47%); 9 samples (21%) were classified grade 0, and 15 (32%) grade I or II. No patient had anti-SSA or anti-SSB antibodies. The presence of SS or sicca syndrome was associated with older age and liver disease activity according to the METAVIR scoring system, but not with the presence of other extrahepatic manifestations or with HCV genotype. A high METAVIR activity score was only statistically associated with primary SS. CONCLUSION: HCV infection appears to account for a subgroup of patients with sicca syndrome in which half the cases meet the definition for SS according to European and Manthorpe criteria. This subgroup is characterized by the constant finding of xerostomia, the absence of classical systemic manifestations observed in primary SS, and the absence of anti-SSA or anti-SSB antibodies. Such characteristics delineate a distinctive, virus associated entity that differs from primary SS.


Asunto(s)
Hepatitis C Crónica/epidemiología , Síndrome de Sjögren/epidemiología , Síndrome de Sjögren/virología , Adulto , Anciano , Anciano de 80 o más Años , Biopsia , Femenino , Hepatitis C Crónica/patología , Humanos , Hígado/patología , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Prospectivos , Glándulas Salivales/patología , Síndrome de Sjögren/patología
4.
Rev Med Interne ; 19(3): 173-9, 1998 Mar.
Artículo en Francés | MEDLINE | ID: mdl-9775137

RESUMEN

PURPOSE: The aim of our study was to investigate the frequency of auto-immune diseases in patients suffering from autoimmune thyroid diseases. METHOD: We realised a retrospective study from 1981 to 1993 including 218 patients suffering from thyroiditis who were followed in the same hospital service. There were 202 women and 16 men with a mean age 49 at the moment their thyroid pathology was discovered. RESULTS: Thirty patients had one or more autoimmune disease associated to their thyroid disorders, representing 13.7% of total patients. The two most frequent autoimmune diseases were lupus and Sjögren's syndrome. In 17 cases the diagnosis of the associated autoimmune disease was made simultaneously. The systemic disease preceded with an 8-year delay the thyroid disease in five cases, and the thyroid disease was annunciatory in eight cases with a delay of 5 years. The frequency of autoimmune diseases seems to be higher in patients suffering from thyroid disorders than in the general population. They are probably common physiopathological mechanisms. CONCLUSION: The frequency of these associations suggests the need for a long-lasting survey of those patients having thyroid disorders. Initial evaluation and a regular checking in patients suffering from an autoimmune disease is recommenced.


Asunto(s)
Arteritis de Células Gigantes/complicaciones , Enfermedad de Graves/complicaciones , Lupus Eritematoso Sistémico/complicaciones , Síndrome de Sjögren/complicaciones , Tiroiditis Autoinmune/complicaciones , Comorbilidad , Femenino , Arteritis de Células Gigantes/diagnóstico , Arteritis de Células Gigantes/epidemiología , Enfermedad de Graves/epidemiología , Humanos , Incidencia , Lupus Eritematoso Sistémico/diagnóstico , Lupus Eritematoso Sistémico/epidemiología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Síndrome de Sjögren/diagnóstico , Síndrome de Sjögren/epidemiología , Tiroiditis Autoinmune/epidemiología
5.
Rev Med Interne ; 18(12): 939-44, 1997.
Artículo en Francés | MEDLINE | ID: mdl-9499997

RESUMEN

Seventy-two cases of primary Sjögren's syndrome, according to the European classification criteria, were studied looking for a correlation between anatomic criteria and clinico-biological signs in this disease. Labial salivary gland biopsy was performed in all patients and anatomic criteria were evaluated according to both Chisholm and Chomette scales. Work-up included recording of functional and clinical signs. Our study shows no clinico-histological correlation in Sjögren's syndrome. Moreover, we did not find any correlation between the two histological scales. We think, therefore, that labial salivary gland biopsy appears to be an important step in Sjögren's syndrome diagnosis according to European criteria. However, it does not present any benefit in patient treatment.


Asunto(s)
Síndrome de Sjögren/patología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Glándulas Salivales Menores/patología , Sensibilidad y Especificidad , Síndrome de Sjögren/clasificación , Síndrome de Sjögren/fisiopatología
6.
Rev Med Interne ; 18(4): 316-9, 1997.
Artículo en Francés | MEDLINE | ID: mdl-9161559

RESUMEN

In a 43-year old male suffering from idiopathic hypereosinophilic syndrome (HES) since 1984, successfully treated with alpha interferon (alpha IFN) for 32 months, a severe Raynaud's phenomenon of the four extremities occurred and eventually evolved into digital necrosis within a few weeks. The arterial echography/doppler and plethysmography patterns were suggestive of isolated small-to medium-size digital artery occlusions. An extensive search for an aetiology of digital necrosis, including complete tests of autoimmunity, remained negative. Two months later, despite alpha IFN withdrawal and intravenous infusions of ilomedin, the digital ischemia evolved to extensive necrosis that necessitated several amputations and a definitive spinal chord stimulation. Pathologic examination of arteries showed no vasculitis but diffuse arterial occlusions by thrombi.


Asunto(s)
Antivirales/efectos adversos , Dedos/patología , Interferón-alfa/efectos adversos , Enfermedad de Raynaud/inducido químicamente , Adulto , Antivirales/uso terapéutico , Arteritis/inducido químicamente , Dedos/irrigación sanguínea , Gangrena , Humanos , Síndrome Hipereosinofílico/tratamiento farmacológico , Interferón alfa-2 , Interferón-alfa/uso terapéutico , Masculino , Proteínas Recombinantes , Factores de Tiempo
7.
Ann Med Interne (Paris) ; 148(7): 477-90, 1997.
Artículo en Francés | MEDLINE | ID: mdl-9538386

RESUMEN

STUDY DESIGNS: To describe retrospectively the experience of the Internal Medicine and Clinical Hematology Departments of a University Hospital on adult acquired hemophilia (AH) caused by autoantibody against factor VIII coagulant (f.VIII:C) activity. Diagnosis, clinical datas, associated diseases, treatment and final outcome are described and compared to the published literature. MATERIAL AND METHODS: All cases admitted in both departments since 1989 were enrolled in the study. Clotting analyses comprised clotting times (activated partial thromboplastin time, prothrombin and thrombine times), measurements of f.VIII:C level, antifactor VIII detection and measurement by the Bethesda method assay, Search for an etiologic factor could not be standardized. All patients were followed until cure, sustained improvement, or death. RESULTS: From 1989 to 1996, AH was diagnosed in nine adult patients. Mean age was 76 +/- 24.6 years (range : 65-89) and sex ratio male to female was 2. Eight bleeding episodes occurred in seven patients, resulting consistently in severe hemorrhagic anemia and leading to hemodynamic failure in two, while two others remained asymptomatic for prolonged periods. The initial levels of f.VIII:C ranged from less than 1% to 20%, and the titers of inhibitors ranged from 0.5 to 100 Bethesda units. An underlying disease, to which the appearance of their inhibitor could be related, either concomitantly or up to 1 year later, was found in four cases including (one case each): rheumatoid arthritis, lupus erythematosus with antiphospholipid syndrome, followed by non-Hodgkin malignant lymphoma, relapsing carcinoma and, biliary tract surgery. Six acute bleeding episodes necessitated symptomatic measures, based on activated prothrombin complex concentrates in four instances, with a good response in all cases. Preparation to minor surgical operations was achieved in two asymptomatic subjects by either highly purified factor VIII concentrations infusion or intravenous 1-desamino-8-D-arginine vasopressin, with a good control of local hemostasis in each case. Three received intravenous immunoglobulins, which resulted in success in one, failure in one and, questionable response in the latter. Immunosuppression, mainly with corticosteroids, cyclophosphamid, or both, was given to seven, resulting in disappearance of inhibitor in five (delay to cure ranged from 2 weeks to 10 months), improvement in one, and failure in one (in this latter case, cure was eventually achieved with the anti-Hodgkin disease MOPP chemotherapy). After a 27-month mean follow-up, six patients experienced a sustained complete response and one a sustained partial response to immuno-suppression, two untreated patients remained asymptomatic, two died later from malignancy (carcinoma and myelodysplastic syndrome). CONCLUSION: AH usually presents as a severe or even a life-threatening disease, necessitating prompt and thorough symptomatic measures directed at the cessation of bleedings and prevention of their relapse. In our experience, no death was attributable to AH or its treatment. Immunosuppression is useful in selected cases, but must be carefully discussed, since it can be highly toxic, especially in the elderly. Given the possibility of a delayed onset of some etiologic factors, a prolonged surveillance of each case of idiopathic AH is mandatory.


Asunto(s)
Autoanticuerpos/análisis , Factor VII/inmunología , Hemofilia A/inmunología , Anciano , Anciano de 80 o más Años , Femenino , Hemofilia A/etiología , Hemofilia A/terapia , Humanos , Masculino , Estudios Retrospectivos
8.
Pathol Biol (Paris) ; 43(4): 329-35, 1995 Apr.
Artículo en Francés | MEDLINE | ID: mdl-7567125

RESUMEN

Prospective study on MRSA nasal cariage was done during two months in an intensive care unit in Limoges University Hospital. Nasal swab specimens were taken daily and cultured on selective and non selective media. Sixty eight patients were included in this study (878 swab collected, 575 MRSA isolated). Patients mean âge was 62 years and stay period mean was 12.3 days (median: 7 days). Among these patients, 16 were already carrying MRSA when entering in the unit and 26 became positive for MRSA during their stay. The mean colonisation delay was 5.5 days (median 4 days). All patients, except one, have shown a nasal carriage during all their stay. During the study period, 17 patients became infected and only two patients neither carried nasal MRSA before and during infection. In all cases, glycopeptide treatment did not affect nasal carriage. Colonisation and infection risk factors were discussed.


Asunto(s)
Infección Hospitalaria/epidemiología , Resistencia a la Meticilina , Mucosa Nasal/microbiología , Infecciones Estafilocócicas/epidemiología , Staphylococcus aureus/aislamiento & purificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Infección Hospitalaria/microbiología , Femenino , Francia/epidemiología , Humanos , Incidencia , Unidades de Cuidados Intensivos , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Prospectivos , Factores de Riesgo , Infecciones Estafilocócicas/microbiología
9.
Ann Med Interne (Paris) ; 146(8): 541-7, 1995.
Artículo en Francés | MEDLINE | ID: mdl-8734078

RESUMEN

A prospective study, including 86 patients with giant cell arteritis proven by temporal artery biopsies, was performed to determine the prevalence of anticardiolipin antibodies, the antibody isotype, the relationship of antibodies to ischemic involvement and their evolution during corticosteroid treatment. Controls were obtained from 50 subjects without vasculitis or autoimmune disorders. Before treatment, 50% of patients' sera contained anti-cardiolipin antibodies (vs 8% in controls, p < 0.0001). These antibodies were IgG-ACL in 36% of patients and IgM-ACL in 17% of patients (vs respectively, 4% and 2% in controls). No significant association was observed between the incidence of ischemic ocular complications and the levels of anti-cardiolipin antibodies. During corticosteroid treatment, the level of anti-cardiolipin antibodies, mostly IgG class, decreased to become negative in 2 months. An increase of these antibodies was observed with the occurrence of relapses in four patients, after the end of corticosteroid therapy. The significance of IgG and IgM antibodies is different in giant cell arteritis. IgG antibodies may be markers of the course of this vasculitis.


Asunto(s)
Anticuerpos Anticardiolipina/inmunología , Arteritis de Células Gigantes/inmunología , Corticoesteroides/uso terapéutico , Anciano , Anciano de 80 o más Años , Femenino , Arteritis de Células Gigantes/complicaciones , Arteritis de Células Gigantes/tratamiento farmacológico , Humanos , Inmunoglobulina G/análisis , Isotipos de Inmunoglobulinas/análisis , Inmunoglobulina M/análisis , Isquemia/etiología , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Recurrencia
11.
Ann Med Interne (Paris) ; 145(3): 168-74, 1994.
Artículo en Francés | MEDLINE | ID: mdl-8092630

RESUMEN

Forty-eight patients with primary Sjögren syndrome are documented together with the results of their baseline investigations. The majority of patients were female (44 out of 48) and mean age was 63.2 years. Common clinical features included 20 parenchymal lung disease, among which 4 had interstitial pulmonary fibrosis and 2 lymphocytic interstitial pneumonitis, 12 neurologic manifestations, 16 Raynaud's phenomenon, 12 arthritis, and 3 gastrointestinal involvement. Haematological features occurred in 15 patients and another autoimmune disease was encountered in 13 cases. These extraglandular manifestations were the dominating reasons for hospital referral in 43.5% of cases, the sicca syndrome were most often only mentioned by the patients after special questioning which explain considerable delay before the diagnosis.


Asunto(s)
Síndrome de Sjögren/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Síndrome de Sjögren/complicaciones
12.
Rev Med Interne ; 14(5): 323-5, 1993 May.
Artículo en Francés | MEDLINE | ID: mdl-7901884

RESUMEN

The authors report a case of polyarteritis nodosa which coincide with serological conversion to parvovirus B19. After review of the literature, they recall the role of this virus in human pathology and also the role of different infectious agents in the PAN pathogenesis.


Asunto(s)
Eritema Infeccioso/etiología , Poliarteritis Nudosa/complicaciones , Anciano , Humanos , Masculino , Parvovirus B19 Humano/patogenicidad
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