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1.
Ann R Coll Surg Engl ; 102(4): e1-e3, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32003571

RESUMEN

Solid pseudopapillary tumours of the pancreas and giant splenic cysts are very rare entities, and their coexistence in a young female patient has not been previously reported in the literature. We present the case of a 27-year-old woman who presented with abdominal pain and two masses on abdominal imaging. A mass located in the right upper quadrant was biopsied, and histological and immunohistochemical analysis showed a solid pseudopapillary tumour of the pancreas. A giant cystic splenic lesion was also noted. The patient underwent a distal pancreatectomy and splenectomy in our referral centre. Margins were negative on histopathological examination. Negative surgical margins were achieved with distal pancreatectomy and splenectomy despite the large size of the pancreatic tumour. The management of solid pseudopapillary tumours of the pancreas is often challenging and the concomitant presence of a giant splenic cyst poses additional challenges to the surgical management of such tumours.


Asunto(s)
Dolor Abdominal/etiología , Quistes/cirugía , Pancreatectomía , Neoplasias Pancreáticas/cirugía , Esplenectomía , Enfermedades del Bazo/cirugía , Adulto , Quistes/complicaciones , Quistes/diagnóstico , Femenino , Humanos , Imagen por Resonancia Magnética , Páncreas/diagnóstico por imagen , Páncreas/cirugía , Neoplasias Pancreáticas/complicaciones , Neoplasias Pancreáticas/diagnóstico , Bazo/diagnóstico por imagen , Bazo/cirugía , Enfermedades del Bazo/complicaciones , Enfermedades del Bazo/diagnóstico , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
2.
Br J Surg ; 100(9): 1138-47, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23775340

RESUMEN

BACKGROUND: The multidisciplinary management of metastatic melanoma now occasionally includes major hepatic resection. The objective of this work was to conduct a systematic review of the literature on liver resection for metastatic melanoma. METHODS: MEDLINE, Embase, the Cochrane Library and Scopus were searched (1990 to December 2012). Studies with at least ten patients undergoing liver resection for metastatic melanoma were included. Data on the outcomes of overall survival (OS) and/or disease-free survival (DFS) were abstracted and synthesized. Hazard ratios (HRs) were derived from survival curves and subjected to meta-analysis using random-effects models. RESULTS: Twenty-two studies involving 579 patients (13 per cent weighted resection rate) who underwent liver resection were included. Study quality was poor to moderate. Median follow-up ranged from 9 to 59 months. Median DFS ranged from 8 to 23 months, and median OS ranged from 14 to 41 months (R0, 22-66 months, R2, 10-16 months; R0 versus R1/R2: HR 0.52, 95 per cent confidence interval (c.i.) 0.37 to 0.73). The OS rate was 56-100 per cent at 1 year, 34-53 per cent at 3 years and 11-36 per cent at 5 years. Median OS with non-operative management ranged from 4 to 12 months. Comparison of OS with resection and non-operative management favoured resection (HR 0.32, 95 per cent c.i. 0.22 to 0.46). CONCLUSION: Radical resection of liver metastases from melanoma appears to improve overall survival compared with non-operative management or incomplete resection, but this observation requires future confirmation as selection bias may have confounded the results.


Asunto(s)
Neoplasias Hepáticas/cirugía , Melanoma/cirugía , Neoplasias Cutáneas , Adulto , Anciano , Femenino , Hepatectomía/métodos , Humanos , Neoplasias Hepáticas/secundario , Masculino , Melanoma/secundario , Persona de Mediana Edad , Resultado del Tratamiento
3.
Eur J Surg Oncol ; 39(6): 548-53, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23522952

RESUMEN

BACKGROUND: This report examines the patterns of presentation, prognostic factors and survival rate of all patients with gallbladder cancer (GBC) evaluated at our tertiary academic hospital over an 11-year period. METHODS: A retrospective review of a prospectively collected database of all patients with GBC presenting between January 1998 and December 2008 was performed. RESULTS: 102 GBC-patients were included: 69 women and 33 men (median age: 65,5 years). Forty-five patients presented with incidental gallbladder cancer (IGC) and 57 with nonincidental cancer (NIGC). Curative surgery rate was 84.4% for IGC and 29.8% for NIGC (p < 0.001). Five-year actuarial survival rate was 63.2% for patients with curative intent surgery and 0% for patients with palliative approach. Patients with IGC had a longer survival rate compared to patients with NIGC (median: 25.8 vs. 4.4 months, p < 0.0001). For patients with radical resection (42 patients), there was no difference between IGC and NIGC. The incidence of liver involvement was respectively 0%, 20.8%, 58.3%, 100% for pT1, pT2, pT3 and pT4 tumors. Univariate analysis showed that survival rate was significantly affected by perineural invasion, T, N and M-stage, R0 resection, liver involvement, CA-19.9. In multivariate analysis, liver involvement was the only independent factor. CONCLUSIONS: Majority of patients with a potentially curable disease had IGC. Almost 80% of patients with NIGC presented with unresectable disease. For patients who underwent resection with curative intent, actuarial 5-year survival was 63.2%. Liver involvement was the only independent prognostic factor. All patients with IGC and a pT2 or more advanced T stage should undergo a second radical resection.


Asunto(s)
Carcinoma/diagnóstico , Carcinoma/mortalidad , Colecistectomía , Neoplasias de la Vesícula Biliar/diagnóstico , Neoplasias de la Vesícula Biliar/mortalidad , Análisis Actuarial , Adulto , Anciano , Carcinoma/secundario , Carcinoma/cirugía , Femenino , Neoplasias de la Vesícula Biliar/patología , Neoplasias de la Vesícula Biliar/cirugía , Hepatectomía , Humanos , Neoplasias Hepáticas/epidemiología , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/cirugía , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Tasa de Supervivencia
4.
J Evol Biol ; 22(10): 2094-103, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19732261

RESUMEN

Diversified bet-hedging, a strategy that leads several individuals with the same genotype to express distinct phenotypes in a given generation, is now well established as a common evolutionary response to environmental stochasticity. Life-history traits defined as diversified bet-hedging (e.g. germination or diapause strategies) display marked differences between populations in spatial proximity. In order to find out whether such differences can be explained by local adaptations to spatially heterogeneous environmental stochasticity, we explored the evolution of bet-hedging dormancy strategies in a metapopulation using a two-patch model with patch differences in stochastic juvenile survival. We found that spatial differences in the level of environmental stochasticity, restricted dispersal, increased fragmentation and intermediate survival during dormancy all favour the adaptive diversification of bet-hedging dormancy strategies. Density dependency also plays a major role in the diversification of dormancy strategies because: (i) it may interact locally with environmental stochasticity and amplify its effects; however, (ii) it can also generate chaotic population dynamics that may impede diversification. Our work proposes new hypotheses to explain the spatial patterns of bet-hedging strategies that we hope will encourage new empirical studies of this topic.


Asunto(s)
Adaptación Fisiológica , Procesos Estocásticos , Genotipo , Modelos Teóricos , Fenotipo
5.
Vector Borne Zoonotic Dis ; 9(3): 243-51, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19480605

RESUMEN

Chagas' disease is a major public health concern in most Latin American countries and its prevention is based on insect vector control. Previous work showed that in the Yucatan peninsula of Mexico, houses are transiently infested by adult Triatoma dimidiata, which then fail to establish sustained colonies. The present study was designed to evaluate the seasonality and possible causes of the dispersal of sylvatic T. dimidiata toward the houses and the subsequent failure of colonization. Dispersal was highly seasonal and correlated with temperature, pressure, and wind speed. Analysis of sex ratio, feeding status, and fecundity of sylvatic populations of T. dimidiata indicated a rather low feeding status and low potential fecundity, suggesting that seasonal dispersal may be associated with foraging for better conditions. Also, feeding status and potential fecundity tended to improve in the domestic habitat but remained largely suboptimal, suggesting that these factors may contribute to the ineffective colonization of this habitat.


Asunto(s)
Conducta Alimentaria/fisiología , Razón de Masculinidad , Triatoma/fisiología , Animales , Enfermedad de Chagas/transmisión , Ecosistema , Femenino , Fertilidad/fisiología , Insectos Vectores/fisiología , Masculino , México , Factores de Tiempo
6.
Proc Biol Sci ; 275(1630): 77-82, 2008 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-17956845

RESUMEN

Sexual selection theory traditionally considers choosiness for mates to be negatively related to intra-sexual competition. Males were classically considered to be the competing, but not the choosy, sex. However, evidence of male choosiness is now accumulating. Male choosiness is expected to increase with an individual's competitive ability, and to decrease as intra-sexual competition increases. However, such predictions have never been tested in field conditions. Here, we explore male mate choice in a spider by studying size-assortative pairing in two natural sites that strongly differ in the level of male-male competition. Unexpectedly, our results demonstrate that mate choice shifts from opportunism to high selectivity as competition between males increases. Males experiencing weak competition did not exhibit size-related mating preferences. By contrast, when competition was intense we found strong size-assortative pairing due to male choice: while larger, more competitive males preferentially paired with larger, more fecund females, smaller males chose smaller females. Thus, we show that mating preferences of males vary with their competitive ability. The distinct preferences exhibited by males of different sizes seem to be an adaptive response to the lower reproductive opportunities arising from increased competition between males.


Asunto(s)
Preferencia en el Apareamiento Animal/fisiología , Arañas/fisiología , Animales , Tamaño Corporal/fisiología , Conducta Competitiva/fisiología , Femenino , Fertilidad/fisiología , Francia , Masculino , Razón de Masculinidad , Arañas/anatomía & histología
7.
Rev Stomatol Chir Maxillofac ; 104(4): 227-30, 2003 Sep.
Artículo en Francés | MEDLINE | ID: mdl-14631234

RESUMEN

The Seip Berardinelli or undiagnosed endocrine metabolic syndrome is a rare autosomal recessive pathology mainly described in families of Portuguese origins. This syndrome presents various metabolic disturbances responsible of various dysmorphies. We report the case of two brothers seen during their childhood for respiratory, speaking and feeding problems related to a class 3 of Angle and macroglossia. The object was to study the interaction between the size of the tongue, the prognathism and the disturbances presented in order to organize early surgery (partial glossectomy).


Asunto(s)
Glosectomía , Lipodistrofia/genética , Niño , Preescolar , Humanos , Macroglosia/cirugía , Masculino , Maloclusión de Angle Clase III/etiología , Prognatismo/etiología , Síndrome
8.
Rev Stomatol Chir Maxillofac ; 104(3): 140-3, 2003 Jun.
Artículo en Francés | MEDLINE | ID: mdl-12931064

RESUMEN

BACKGROUND: EEC (ectodactyly-ectodermal dysplasia-cleft lip and palate) is a rare disease transmitted by autosomal dominant inheritance with variable penetrance and weak expressivity. Clinical expression is thus very variable. Besides the three signs defining the syndrome, other manifestations include anomalous lacrimal ducts, urogenital malformations, transmission deafness, facial dysmorphism, and mental retardation. In 1995, Roelfsema and Cobben established a severity score on the basis of data in the literature. MATERIAL AND METHODS: We analyzed retrospectively the cases of 5 patients followed from 1980 to 2000 in two University Hospitals in France. Malformations were detailed and the Roelfsema and Cobben score was calculated. The real degree of disability was estimated from social activity level. We searched for a correlation between the Roelfsema and Cobben score and the real degree of disability. RESULTS: Our findings showed a poor correlation between disability and the Roelfsema and Cobben score. We proposed a new score which takes into account social disability. DISCUSSION: Our study revealed that the Roelfsema and Cobben score overly emphasizes anatomic malformations without taking into account natural adaptation to the social environment. Inversely, the Roelfsema and Cobben score gives little importance to invisible anomalies despite their invalidating effect.


Asunto(s)
Anomalías Múltiples/patología , Fisura del Paladar/patología , Displasia Ectodérmica/patología , Deformidades Congénitas del Pie/patología , Deformidades Congénitas de la Mano/patología , Anomalías Múltiples/clasificación , Adaptación Psicológica , Adolescente , Adulto , Anciano , Niño , Preescolar , Labio Leporino/patología , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Síndrome
9.
Chir Main ; 20(5): 388-90, 2001 Oct.
Artículo en Francés | MEDLINE | ID: mdl-11723780

RESUMEN

Acute form of carpal tunnel syndrome is the less common presentation. Several etiologies are known as rheumatologic, hemopathic, endocrine or pregnant disorders and traumatic. Authors report a non yet described traumatic etiology, consecutive to hamate and triquetral fractures. Patient presented five hours after initial traumatism, a typical presentation of median nerve compression at wrist, with subjective and objective symptoms as pathologic Weber test. A classical median nerve release was performed in emergency. Nerve recuperation was complete two days after surgery, as usual in such pathology. This new etiology must be known; actually, nerve recuperation in acute carpal tunnel syndrome is time dependent.


Asunto(s)
Síndrome del Túnel Carpiano/etiología , Fracturas Cerradas/complicaciones , Traumatismos de la Muñeca/complicaciones , Enfermedad Aguda , Adolescente , Síndrome del Túnel Carpiano/patología , Síndrome del Túnel Carpiano/cirugía , Humanos , Masculino
10.
Oecologia ; 122(4): 493-499, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28308341

RESUMEN

We test the adaptive value of clutch size observed in a natural population of the chestnut weevil Curculio elephas. Clutch size is defined as the number of immatures per infested chestnut. In natural conditions, clutch size averages 1.7 eggs. By manipulating clutch size in the field, we demonstrate that deviations from the theoretical "Lack clutch size", estimated as eight immatures, are mainly due to proximate and delayed effects of clutch size on offspring performance. We show the existence of a trade-off between clutch size and larval weight. The latter, a key life-history trait, is highly correlated with fitness because it is a strong determinant of larval survival and potential fecundity of offspring females. The fitness of different potential oviposition strategies characterized by their clutch sizes, ranging from one to nine immatures, was calculated from field- estimated parameters. Chestnut weevil females obtain an evolutionary advantage by laying their eggs singly, since, for instance, fitness of single-egg clutches exceeds fitness of two-egg clutches and four-egg clutches by 8.0% and 15.1% respectively.

11.
J Bacteriol ; 178(11): 2999-3007, 1996 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8655472

RESUMEN

The psychrotrophic bacterium Arthrobacter globiformis SI55 was grown at 4 and 25 degrees C, and the cell protein contents were analyzed by two-dimensional electrophoresis. Cells subjected to cold shocks of increasing magnitude were also analyzed. Correspondence analysis of protein appearance distinguished four groups of physiological significance. Group I contained cold shock proteins (Csps) overexpressed only after a large temperature downshift. Group II contained Csps with optimal expression after mild shocks. Group III contained proteins overexpressed after all cold shocks. These last proteins were also overexpressed in cells growing at 4 degrees C and were considered to be early cold acclimation proteins (Caps). Group IV contained proteins which were present at high concentrations only in 4 degrees C steady-state cells and appeared to be late Caps. A portion of a gene very similar to the Escherichia coli cspA gene (encoding protein CS7.4) was identified. A synthetic peptide was used to produce an antibody which detected a CS7.4-like protein (A9) by immunoblotting two-dimensional electrophoresis gels of A. globiformis SI55 total proteins. Unlike mesophilic microorganisms, this CS7.4-like protein was still produced during prolonged growth at low temperature, and it might have a particular adaptive function needed for balanced growth under harsh conditions. However, A9 was induced at high temperature by chloramphenicol, suggesting that CS7.4-like proteins have a more general role than their sole implication in cold acclimation processes.


Asunto(s)
Arthrobacter/fisiología , Proteínas Bacterianas/biosíntesis , Frío , Aclimatación , Secuencia de Aminoácidos , Proteínas Bacterianas/genética , Secuencia de Bases , Cloranfenicol/farmacología , Genes Bacterianos , Datos de Secuencia Molecular
12.
Artículo en Inglés | MEDLINE | ID: mdl-9960204
13.
Oecologia ; 93(3): 367-373, 1993 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28313437

RESUMEN

Spreading of emergence over several years due to prolonged diapause in some larvae was shown in the chestnut weevil. Depending on the year the larvae buried themselves in the ground, 32-56% of live adults emerged after 2 or 3 years of underground life. Variability in the duration of diapause was assumed to correspond to tactics of adaptative "coin-flipping" plasticity. This plasticity must allow the chestnut weevil to respond to the unpredictability of its habitat as measured by the irregularity of chestnut production and summer drought. Indeed, fecundity and adult longevity did not lessen after 2 years of underground life. No drastic decrease in the population size of weevils occurs after bad years; for instance when the number of chestnuts on the study tree is less than 10 000, passers-by can collect all the fruit and about 95% of larvae developing in chestnuts are destroyed. Diapause nature (simple or prolonged) may be related to moisture and gas rates in the ground from October to December. These factors acting in autumn are not known to be involved in the physiological mechanisms that control the production of chestnuts.

14.
Oecologia ; 96(3): 383-390, 1993 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28313654

RESUMEN

In the chestnut weevil Curculio elephas, adult emergences spread over 3 or 4 years due to prolonged larval diapause in some individuals. Weevils with an extended diapause emerge, on the average, 1-10 days before those with simple diapause, but whatever the age of insects, emergences occur always from mid-August to early October. When the summer is dry, some adults cannot emerge because of the hardness of the soil. Emergence sucess of adults is smaller in females than in males. The result is that the sex ratio is female-biased before emergence and male-biased after. Summer drought cannot be predicted by the chestnut weevil, and when the soil is dry 27-78% of females cannot emerge and do not reproduce. The year after a summer drought, many reproducing females may emerge from larvae with prolonged diapause. These results suggest an evolutionary influence on the variability in diapause duration. Computer simulations and observations do not support the hypothesis that the main cause of variation in diapause length is the existence of several distinct genotypes within populations. On the contrary, our data strengthen the hypothesis for coin-flipping plasticity discussed in a previous paper.

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