RESUMO
Changes in temperature have occurred throughout Earth's history. However, current warming trends exacerbated by human activities impose severe and rapid loss of biodiversity. Although understanding the mechanisms orchestrating organismal response to climate change is important, remarkably few studies document their role in nature. This is because only few systems enable the combined analysis of genetic and plastic responses to environmental change over long time spans. Here, we characterize genetic and plastic responses to temperature increase in the aquatic keystone grazer Daphnia magna combining a candidate gene and an outlier analysis approach. We capitalize on the short generation time of our species, facilitating experimental evolution, and the production of dormant eggs enabling the analysis of long-term response to environmental change through a resurrection ecology approach. We quantify plasticity in the expression of 35 candidate genes in D. magna populations resurrected from a lake that experienced changes in average temperature over the past century and from experimental populations differing in thermal tolerance isolated from a selection experiment. By measuring expression in multiple genotypes from each of these populations in control and heat treatments, we assess plastic responses to extreme temperature events. By measuring evolutionary changes in gene expression between warm- and cold-adapted populations, we assess evolutionary response to temperature changes. Evolutionary response to temperature increase is also assessed via an outlier analysis using EST-linked microsatellite loci. This study provides the first insights into the role of plasticity and genetic adaptation in orchestrating adaptive responses to environmental change in D. magna.
Assuntos
Evolução Biológica , Daphnia/genética , Temperatura , Termotolerância/genética , Animais , Mudança Climática , Etiquetas de Sequências Expressas , Expressão Gênica , Genótipo , Lagos , Repetições de Microssatélites , Modelos GenéticosRESUMO
Allozyme variation at the phosphoglucose isomerase (PGI) locus in the Glanville fritillary butterfly (Melitaea cinxia) is associated with variation in flight metabolic rate, dispersal rate, fecundity and local population growth rate. To map allozyme to DNA variation and to survey putative functional variation in genomic DNA, we cloned the coding sequence of Pgi and identified nonsynonymous variable sites that determine the most common allozyme alleles. We show that these single-nucleotide polymorphisms (SNPs) exhibit significant excess of heterozygotes in field-collected population samples as well as in laboratory crosses. This is in contrast to previous results for the same species in which other allozymes and SNPs were in Hardy-Weinberg equilibrium or exhibited an excess of homozygotes. Our results suggest that viability selection favours Pgi heterozygotes. Although this is consistent with direct overdominance at Pgi, we cannot exclude the possibility that heterozygote advantage is caused by the presence of one or more deleterious alleles at linked loci.
Assuntos
Borboletas/fisiologia , Glucose-6-Fosfato Isomerase/genética , Polimorfismo de Nucleotídeo Único/genética , Animais , Borboletas/genética , Borboletas/metabolismo , Feminino , Variação Genética , Genótipo , Masculino , FenótipoRESUMO
OBJECTIVE: To evaluate if cervical length predicts prepartum bleeding and emergency Cesarean section in cases of placenta previa. METHODS: Between September 2005 and September 2007, cervical length was measured by transvaginal ultrasound in women with complete placenta previa persisting into the third trimester of pregnancy. A complete follow-up of pregnancy was obtained in all cases. RESULTS: Overall, 59 women were included in the study group. The mean +/- SD gestational age at ultrasound was 30.7 +/- 2.7 weeks and the cervical length was 36.9 +/- 8.8 mm. Cesarean delivery was performed in all cases, at a mean gestational age of 34.7 +/- 2.3 weeks. Twenty-nine (49.1%) of the women presented prepartum bleeding and 12 (20.3%) required an emergency Cesarean section prior to 34 completed weeks due to massive hemorrhage. Cervical length did not differ significantly between cases with and those without prepartum bleeding (35.3 +/- 9.3 mm vs. 38.4 +/- 8.2 mm; P = 0.18), but was significantly shorter among patients who underwent emergency Cesarean section < 34 weeks due to massive hemorrhage compared with patients who underwent elective Cesarean section (29.4 +/- 5.7 mm vs. 38.8 +/- 8.5 mm; P = 0.0006). CONCLUSIONS: Transvaginal sonographic cervical length predicts the risk of emergency Cesarean section < 34 weeks in women with complete placenta previa.
Assuntos
Medida do Comprimento Cervical , Cesárea/estatística & dados numéricos , Trabalho de Parto Prematuro/etiologia , Placenta Prévia/diagnóstico por imagem , Hemorragia Uterina , Adulto , Feminino , Humanos , Valor Preditivo dos Testes , Gravidez , Terceiro Trimestre da Gravidez , Estudos ProspectivosRESUMO
The Glanville fritillary butterfly (Melitaea cinxia) has been studied in the Aland Islands in Finland since 1991, where it occurs as a classic metapopulation in a large network of 4000 dry meadows. Much ecological work has been conducted on this species, but population genetic studies have been hampered by paucity of suitable genetic markers. Here, using single nucleotide polymorphisms and microsatellites developed for the Glanville fritillary, we examine the correspondence between the demographic and genetic spatial structures. Given the dynamic nature of the metapopulation, the current genetic spatial structure may bear a signal of past changes in population sizes and past patterns of gene flow rather than reflect the current demographic structure or landscape structure. We analyse this question with demographic data for 10 years, using the Rand index to assess the similarity between the genetic, demographic, and landscape spatial structures. Our results show that the current genetic spatial structure is better explained by the past rather than by the current demographic spatial structure or by the spatial configuration of the habitat in the landscape. Furthermore, current genetic diversity is significantly explained by past metapopulation sizes. The time lag between major demographic events and change in the genetic spatial structure and diversity has implications for the study of spatial dynamics.
Assuntos
Borboletas/genética , Variação Genética , Animais , Finlândia , Genótipo , Repetições de Microssatélites/genética , Polimorfismo de Nucleotídeo ÚnicoRESUMO
OBJECTIVE: Both arterial hypertension and chronic hepatitis are common disorders. The relationship between arterial pressure and liver cirrhosis has been extensively studied, but no studies are available in chronic hepatitis (CH). Recently, a few studies have reported that treatment with angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin-receptor blockers (ARBs), commonly used in arterial hypertension, reduce hepatic fibrosis in patients with viral CH and in nonalcoholic steatohepatitis. This study was aimed at comparing the evolution of post-viral CH in patients with/without concomitant essential hypertension. METHODS: Two sets of observations were carried out: (a) a cross-sectional cohort study of 95 patients with viral CH, to compare the severity of histological and biochemical data at diagnosis, in relation to pharmacologically treated essential hypertension, and (b) a retrospective study with the observation of 254 patients with CH of viral etiology, followed up from 2 to 20 years, to establish the natural history of viral CH in relation to treated essential hypertension. RESULTS: In the cross-sectional analysis, patients with treated hypertension had a significantly older age at diagnosis of CH (51.4 +/- 8.4 years vs. 46.2 +/- 12.2 in normotensive; P < 0.001) and histological evidence of less severe necro-inflammatory liver damage. ALT levels were also lower (109.8 +/- 62.5 U/L vs. 166.0+/-169.5 in normotensive; P < 0.001) as were endothelin-1 levels (0.74 +/- 0.97 vs. 1.77 +/- 1.51 fmol/mL; P < 0.001). The retrospective study confirmed an older age at diagnosis in patients with treated hypertension (48.7 +/- 9.8 vs. 41.9 +/- 11.8 years; P < 0.001) and lower death rates (2.2% vs. 11%; P < 0.05). CONCLUSIONS: The evolution of post-viral CH seems to be less severe in subjects with essential hypertension, possibly in relation to treatment with antihypertensive drugs.
Assuntos
Anti-Hipertensivos/uso terapêutico , Hepatite Crônica/complicações , Hepatite Viral Humana/complicações , Hipertensão/complicações , Adulto , Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Estudos Transversais , Feminino , Hepatite Crônica/tratamento farmacológico , Hepatite Viral Humana/tratamento farmacológico , Humanos , Hipertensão/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do TratamentoRESUMO
Posidonia oceanica is an endemic seagrass in the Mediterranean Sea, where it provides important ecosystem services and sustains a rich and diverse ecosystem. P. oceanica meadows extend from the surface to 40 meters depth. With the aim of boosting research in this iconic species, we generated a comprehensive RNA-Seq data set for P. oceanica by sequencing specimens collected at two depths and two times during the day. With this approach we attempted to capture the transcriptional diversity associated with change in light and other depth-related environmental factors. Using this extensive data set we generated gene predictions and identified an extensive catalogue of potential Simple Sequence Repeats (SSR) markers. The data generated here will open new avenues for the analysis of population genetic features and functional variation in P. oceanica. In total, 79,235 contigs were obtained by the assembly of 70,453,120 paired end reads. 43,711 contigs were successfully annotated. A total of 17,436 SSR were identified within 13,912 contigs.
Assuntos
Alismatales/genética , Transcriptoma , Ecossistema , Genética Populacional , Mar Mediterrâneo , Repetições de MicrossatélitesRESUMO
Interleukin-8 is a cytokine produced by mononuclear cells that is involved in polymorphonuclear neutrophil leukocyte (PMN) recruitment and activation. Several studies have previously demonstrated a leukocyte activation during hypercholesterolemia and 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors have been found to play a role in the prevention of atherothrombotic disease. The purpose of this study was to determine interleukin-8 (IL-8) mRNA expression and ex vivo production from peripheral blood mononuclear cells (PBMCs) and IL-8-dependent PMN activation of hypercholesterolemic (HC) patients with respect to normocholesterolemic (NC) subjects. Using Northern blot analysis, we found a four- and threefold increase in the amount of IL-8 transcript in PBMC from HC patients, in unstimulated and LPS stimulated cultures, respectively. A specific immunoassay showed a correspondingly significant increase of IL-8 immunoactivity in the conditioned medium of PBMC from HC subjects as compared with controls (unstimulated PBMC: 15 +/- 4 vs. 4.2 +/- 3 ng/ml; P < 0.0001; LPS stimulated PBMC: 65.3 +/- 8 vs. 36.6 +/- 9 ng/ml; P < 0.0001). PMN of HC patients stimulated with IL-8 showed a reduced elastase release with respect to NC subjects before physiological granule release after f-Met-Leu-Phe (fMLP) treatment. These results indicate an upregulation of the IL-8 system in dyslipidemic patients and provide evidence for ongoing in vivo IL-8-dependent PMN activation during hypercholesterolemia.
Assuntos
Hipercolesterolemia/sangue , Interleucina-8/biossíntese , Leucócitos Mononucleares/metabolismo , Neutrófilos/metabolismo , RNA Mensageiro/genética , Adulto , Northern Blotting , Células Cultivadas , Colesterol/sangue , Feminino , Expressão Gênica , Humanos , Interleucina-8/sangue , Interleucina-8/genética , Elastase de Leucócito/biossíntese , Elastase de Leucócito/efeitos dos fármacos , Leucócitos Mononucleares/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Ativação de Neutrófilo , Neutrófilos/efeitos dos fármacosRESUMO
A new case of pregnancy in a 29-year-old woman with trisomy 21 is described. She gave birth to a male infant, chromosomally and phenotypically normal, who died the day after delivery due to prematurity. Thirty pregnancies of 26 affected mothers, including the present woman, resulted in 10 children with Down syndrome, 18 children (1 set of twins) without Down syndrome, and 3 spontaneous abortions. Although rare, pregnancies in women with Down syndrome could become more frequent, increasing the importance of genetic, reproductive, and obstetric problems. These problems are reviewed with special reference to the occurrence of nonspecific abnormalities in chromosomally normal children, difficulties in labor and delivery, and frequency of prematurity and low birth weight.
Assuntos
Síndrome de Down/genética , Complicações na Gravidez , Adulto , Feminino , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Recém-Nascido Prematuro , Gravidez , RiscoRESUMO
A new technique is presented for funipuncture under ultrasound guidance using a biopsy guide and a 20/25-gauge needle combination. The 20-gauge needle was used for uterine entry and the 25-gauge needle for the actual cord puncture. The method was used for sampling fetal blood in 262 pregnancies with 264 fetuses (two sets of twins) between 17-39 weeks, at risk for beta-thalassemia, chromosomal disorders, TORCH infection, fetal hypoxia, and Rh-isoimmunization. Pure fetal blood was aspirated from 241 fetuses (91.3%), including the twins. The procedure lasted less than 5 minutes in 76.5% of the cases and less than 10 minutes in 90.1% of the cases. Intra-amniotic bleeding was seen in only 23.1% of the cases, and fetal bradycardia was not noted. Forty-four pregnancies were terminated after the diagnosis of genetic or infectious disease. Seven fetuses at risk for Rh-isoimmunization, found to be Rh-positive and anemic, were transfused immediately after blood sampling using the same needle. Of the 220 continuing pregnancies, there were 14 fetal losses (three before 28 weeks and 11 after 28 weeks or during the perinatal period). A probable etiology for the loss was found in 11 cases. These included one severely Rh-isoimmunized hydropic fetus who died in utero after transfusion at 26 weeks, one fetus who died in utero at 31 weeks following a car accident, and nine malformed newborns. The corrected rate for fetal losses probably related to the procedure was thus 0.9% before 28 weeks and 0.8% after 28 weeks. This new funipuncture technique seems to have several advantages over the freehand and/or biopsy-guided single-needle techniques.
Assuntos
Coleta de Amostras Sanguíneas/métodos , Punções/métodos , Cordão Umbilical , Biópsia por Agulha , Coleta de Amostras Sanguíneas/efeitos adversos , Feminino , Humanos , Gravidez , Punções/efeitos adversos , Punções/instrumentação , UltrassonografiaRESUMO
The uterus and ovaries of 50 patients with polycystic ovarian disease (PCOD) and 30 eumenorrheic women were studied with a real-time ultrasound mechanical sector scanner. Uterine and ovarian volumes (UV and OV) and the OV/UV ratio were calculated, and ovarian morphology was classified as prevalently solid and cystic. Both ovaries were displayed in 44 of the PCOD and in 25 of the normal patients and appeared bilaterally solid, cystic, or with different morphology, respectively, in 43.2%, 47.7%, and 9.1% of cases in the former group and in 76%, 20%, and 4% in the latter group. Statistically significant differences between normal and PCOD patients were found in OV, UV, and OV/UV ratio. Bilaterally enlarged ovaries with multiple tiny cysts, the classic ultrasonographic picture of the polycystic ovary, were found in only 16 (36.3%) of the PCOD cases, while 34 (77.3%) had an OV/UV ratio greater than 1 standard deviation above the mean. Four ultrasonographic ovarian patterns were observed in the PCOD patients: enlarged cystic; enlarged solid; normal-sized cystic; and normal-sized solid. These findings emphasize the need for a reconsideration of the ultrasonographic criteria of PCOD.
Assuntos
Síndrome do Ovário Policístico/diagnóstico , Ultrassonografia , Adolescente , Adulto , Feminino , Humanos , Ovário/patologia , Útero/patologiaRESUMO
Five normally menstruating women were treated, in an attempt to induce development of multiple follicles, with pharmacologic doses of purified human urinary follicle-stimulating hormone (hU-FSH) and (in another instance) with human menopausal gonadotropin (hMG) administered on the second and third days after the onset of menses. All of the cycles were ovulatory: the follicular phase was short and the luteal phase length was normal in both hMG and hU-FSH treatment. No substantial differences were seen between the two types of treatment in regard to plasma values of FSH, luteinizing hormone (LH), estradiol (E2), testosterone, and progesterone (P). FSH, E2, and P increased to supraphysiologic levels, and LH fluctuated within the normal range. On ultrasound examination, a large number of growing and matured follicles were visualized during both treatments: at human chorionic gonadotropin administration, multiple preovulatory follicles (greater than or equal to 15 mm) and only a few small follicles (less than 10 mm) were imaged, without any difference between the two types of treatment. Multiple corpora lutea were often obtained. These data underline that pharmacologic doses of FSH alone are able to induce the growth of multiple preovulatory follicles when the initiation of stimulation is timed early. Besides this, exogenous LH does not seem to interfere with follicular recruitment, and it is not required for follicular maturation and ovarian steroidogenesis when endogenous normal LH mean values are present.
Assuntos
Hormônio Foliculoestimulante/farmacologia , Menotropinas/farmacologia , Folículo Ovariano/fisiologia , Ovulação/efeitos dos fármacos , Adulto , Gonadotropina Coriônica/farmacologia , Estradiol/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Hormônio Foliculoestimulante/urina , Fase Folicular/efeitos dos fármacos , Humanos , Fase Luteal/efeitos dos fármacos , Hormônio Luteinizante/sangue , Folículo Ovariano/efeitos dos fármacos , Gravidez , Progesterona/sangue , Testosterona/sangue , UltrassonografiaRESUMO
Modern ultrasound equipments allow a detailed investigation of the fetal brain from a very early stage of development. Congenital anomalies arising from or involving the central nervous system can be accurately predicted. On the basis of their personal experience, which includes 48 cases, and of a review of the current literature, the authors discuss criteria for the intrauterine diagnosis and obstetrical management of intracranial anomalies such as hydrocephalus, holoprosencephaly, cephaloceles, porencephaly, hydranencephaly, and microcephaly.
Assuntos
Encéfalo/anormalidades , Diagnóstico Pré-Natal , Ultrassonografia , Encéfalo/embriologia , Encefalocele/diagnóstico , Feminino , Humanos , Hidranencefalia/diagnóstico , Hidrocefalia/diagnóstico , Microcefalia/diagnóstico , Gravidez , PrognósticoRESUMO
Nine infertile patients, suffering from polycystic ovaries, were treated with human urinary FSH and hCG (eight cases) to induce ovulation. Oestrone, oestradiol, 17 alpha-hydroxyprogesterone, testosterone and androstenedione serum levels increased during the treatment. A decrease in luteinizing hormone serum levels was noticed, and in five cases a spontaneous peak was observed. No changes were noted in 5 alpha-dihydrotestosterone serum levels. Ultrasound scanning of the ovaries often revealed multiple follicles at different speeds and stages of growth and their marked turnover was observed. The beginning of the LH spontaneous surge was precocious compared to the normal ovulating follicular sizes: it does not appear that an optimum size exists but when the LH peak occurred too prematurely, ovulation did not take place. Administration of hCG seems to be necessary as spontaneous peaks of LH are not always followed by rupture of the follicle. Ultrasound scanning plays an important role in monitoring ovulation induction, while oestradiol and 17 alpha-hydroxyprogesterone serum levels are not good indicators of follicular maturity in multifollicular growth. Ovulation occurred in eight patients; four conceptions were obtained, one of which resulted in abortion. No ovarian hyperstimulations were observed.
Assuntos
Menotropinas/administração & dosagem , Cistos Ovarianos/tratamento farmacológico , Indução da Ovulação/métodos , Adolescente , Adulto , Androstenodiona/sangue , Di-Hidrotestosterona/sangue , Estradiol/sangue , Estrona/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Humanos , Hidroxiprogesteronas/sangue , Hormônio Luteinizante/sangue , Cistos Ovarianos/sangue , Cistos Ovarianos/diagnóstico , Testosterona/sangue , UltrassonografiaRESUMO
AIMS AND BACKGROUND: The prognosis for ovarian cancer patients depends on the stage at diagnosis. As a prerequisite for any proposed procedure for ovarian cancer screening, high levels of specificity should be obtained using combinations of tests. Based on preliminary data from an ongoing feasibility study, this report is focused on the possible gain in specificity provided by fine-needle aspiration of occult ovarian masses detected by ultrasound. METHODS: Ultrasonography was used as a basic test, and fine-needle aspiration was obtained from selected patients. Those with (a) positive aspiration cytology or histology, (b) complex or solid masses showing volume increase, (c) complex or irregular masses and inadequate samples, and (d) recurrent cystic lesions were operated on. RESULTS: A total of 3541 asymptomatic patients 50-69 years of age underwent ultrasonography, and 98 were selected for fine-needle aspiration. Of these, 19 (positivity rate 19/3541 or 0.5%) were operated on. Two ovarian cancer cases (FIGO Stage II and III) were detected (detection rate 2/3541 or 0.6 x 1,000; positive predictive value 2/19 or 10.5%). Specificity was 3443/3539 or 97.3% for ultrasound alone and 3522/3539 or 99.5% for the procedure as a whole. Surgical exploration for relapses of benign cysts reduced by some 50% the potential gain in positive predictive value provided by aspiration cytology compared with ultrasound alone. CONCLUSIONS: Although fine-needle aspiration has improved the performance of ultrasound, this 2-level procedure does not appear to achieve acceptable levels of specificity.