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1.
Br J Anaesth ; 120(3): 517-524, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29452808

RESUMO

BACKGROUND: We conducted this study to investigate whether norepinephrine increases cardiac contractility when administered during the early phase of septic shock. METHODS: We studied 38 patients with septic shock who had been resuscitated for <3 h and whose mean arterial pressure (MAP) remained <65 mm Hg. Echocardiographic variables were obtained before (T0) and after either initiation or an increase in the dose of a norepinephrine infusion to increase MAP to ≥ 65 mm Hg (T1). We collected left ventricular ejection fraction (LVEF), velocity-time integral of the left ventricular outflow tract (VTI), tissue Doppler imaging of mean systolic velocity of the lateral tricuspid annulus (Sa) and of the lateral mitral annulus (Sm), and tricuspid annular plane systolic excursion (TAPSE). RESULTS: There were significant (P<0.05) increases from T0 to T1 in MAP [mean (sd): from 56 (7) to 80 (9) mm Hg], LVEF [from 49 (13) to 56 (13)%], VTI [from 18 (5) to 20 (6) cm], Sm [from 10.8 (5.1) to 12.1 (5.0) cm s-1], TAPSE [from 1.8 (0.5) to 2.0 (0.5) cm], and Sa [from 13.0 (5.6) to 15.1 (6.4) cm s-1]. In the subgroup of 15 patients with LVEF ≤45%, significant increases in VTI [from 16 (8) to 18 (7) cm] and in LVEF [from 36 (7) to 44 (10)%] were observed. CONCLUSIONS: Norepinephrine administration during early resuscitation in patients with septic shock increased the cardiac systolic function despite the presumed increase in left ventricular afterload secondary to the increased arterial pressure. Whether such an effect persists over time remains to be evaluated. CLINICAL TRIAL REGISTRATION: NCT02750683.


Assuntos
Agonistas alfa-Adrenérgicos/farmacologia , Contração Miocárdica/efeitos dos fármacos , Norepinefrina/farmacologia , Choque Séptico/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estimulação Química , Resultado do Tratamento
2.
Rev Neurol (Paris) ; 167(6-7): 522-5, 2011.
Artigo em Francês | MEDLINE | ID: mdl-21186036

RESUMO

INTRODUCTION: Brachial plexus is rarely involved in "Saturday night palsy". CASE REPORT: A young man was admitted for numbness and weakness of his right upper limb after awaking from sleep. Neurophysiological studies, consistent with brachial plexopathy, revealed presence of proximal conduction blocks. Patient presented spontaneous clinical and neurophysiological improvement. DISCUSSION: Diagnosis of compressive brachial plexopathy needs to eliminate other causes of neuropathy with conduction block.


Assuntos
Neuropatias do Plexo Braquial/patologia , Síndromes de Compressão Nervosa/patologia , Paralisia/patologia , Paralisia do Sono/patologia , Neuropatias do Plexo Braquial/etiologia , Eletromiografia , Potencial Evocado Motor/fisiologia , Humanos , Masculino , Síndromes de Compressão Nervosa/complicações , Condução Nervosa/fisiologia , Paralisia/etiologia , Recuperação de Função Fisiológica , Paralisia do Sono/etiologia , Estimulação Magnética Transcraniana , Adulto Jovem
3.
Rev Mal Respir ; 25(7): 853-6, 2008 Sep.
Artigo em Francês | MEDLINE | ID: mdl-18946411

RESUMO

INTRODUCTION: Tuberculosis is the most common infectious complication in HIV infected patients. The incidence of tuberculosis and the proportion of disseminated disease increase with more severe immuno-suppression. Septic shock and multiple organ failure are uncommon but are of markedly bad prognostic significance. CASE REPORT: A forty-four year old HIV seropositive man was admitted to the intensive care unit (ICU) with acute respiratory distress. The patient had been febrile for the previous two weeks. His thoracic radiograph showed a discrete interstitial infiltrate and at bronchoscopy small whitish granulations were observed in the main bronchi. All bacteriological investigations remained negative at the time of ICU admission. The patient died sixteen hours later due to multiple organ failure. Mycobacteria were identified after patient's death on the smear from BAL, from blood cultures, and in a postmortem liver biopsy. CONCLUSIONS: Septic shock is an infrequent complication of disseminated tuberculosis. Mortality is very high. Treatment should be started early in cases with a high diagnostic suspicion.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS , Insuficiência de Múltiplos Órgãos/etiologia , Choque Séptico/etiologia , Tuberculose/complicações , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Adulto , Fármacos Anti-HIV/uso terapêutico , Broncoscopia , Humanos , Terapia de Imunossupressão , Unidades de Terapia Intensiva , Masculino , Insuficiência de Múltiplos Órgãos/mortalidade , Radiografia Torácica , Insuficiência Respiratória/etiologia , Tuberculose/diagnóstico por imagem
4.
Magnes Res ; 19(1): 46-52, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16846100

RESUMO

Some previous studies have reported the involvement of magnesium (Mg) deficiency in children with ADHD syndrome. In this work, 40 children with clinical symptoms of ADHD were followed clinically and biologically during a magnesium-vitamin B6 (Mg-B6) regimen (6 mg/kg/d Mg, 0.6 mg/kg/d vit-B6) which was set up for at least 8 weeks. Symptoms of ADHD (hyperactivity, hyperemotivity/ aggressiveness, lack of attention at school) were scored (0-4) at different times; in parallel, intraerythrocyte Mg2+ (Erc-Mg) and blood ionized Ca2+ (i-Ca) were measured. Children from the ADHD group showed significantly lower Erc-Mg values than control children (n = 36). In almost all cases of ADHD, Mg-B6 regimen for at least two months significantly modified the clinical symptoms of the disease: namely, hyperactivity and hyperemotivity/aggressiveness were reduced, school attention was improved. In parallel, the Mg-B6 regimen led to a significant increase in Erc-Mg values. When the Mg-B6 treatment was stopped, clinical symptoms of the disease reappeared in few weeks together with a decrease in Erc-Mg values. This study brings additional information about the therapeutic role of a Mg-B6 regimen in children with ADHD symptoms.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Suplementos Nutricionais , Magnésio , Vitamina B 6 , Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Cálcio/sangue , Criança , Pré-Escolar , Método Duplo-Cego , Feminino , Humanos , Magnésio/administração & dosagem , Magnésio/sangue , Magnésio/uso terapêutico , Masculino , Testes Neuropsicológicos , Vitamina B 6/administração & dosagem , Vitamina B 6/uso terapêutico
5.
Magnes Res ; 19(1): 53-62, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16846101

RESUMO

Previous studies reported positive results with the use of Mg-vitamin B6 in autism. Despite these reports, this intervention remains controversial. In order to study relationships between changes in clinical symtoms and biological parameters, 33 children (mean age: 4 [1-10] years old) with clinical symptoms of pervasive developmental disorder or autism (PDD, as defined in DSM-IV) were followed for at least 6 months; another group of 36 children (same age) devoided of any known pathology was used as control. All PDD children received a magnesium-vit B6 (Mg-B6) regimen (6 mg/kg/d Mg and 0.6 mg/kg/d vit B6). Intraerythrocyte Mg2+ (Erc-Mg), serum Mg2+ (s-Mg) and blood ionized Ca2+ (i-Ca) were measured before and after treatment. Clinical symptoms of PDD were scored (0 to 4). In contrast to s-Mg or i-Ca, PDD children exhibited significantly lower Erc-Mg values than controls (2.17 +/- 0.4 versus 2.73 +/- 0.23 mmol/L; 16/33). The Mg-B6 regimen led to an increase in Erc-Mg values (2.42 +/- 0.41 (after) versus 2.17 +/- 0.4 mmol/l (before), 11/17) and this supplementation improved PDD symptoms in 23/33 children (p < 0.0001) with no adverse effects: social interactions (23/33), communication (24/33), stereotyped restricted behavior (18/33), and abnormal/delayed functioning (17/33); 15/33 children were improved in the first three groups of symptoms. When the Mg-B6 treatment was stopped, PDD symtoms reappeared in few weeks. A statistically significant relationship was found in Erc-Mg values from children before treatment and their mothers. In conclusion, this study suggests that the behavioral improvement observed with the combination vitamin B6-magnesium in PDD/autism is associated with concomitant modifications of Erc-Mg values.


Assuntos
Transtorno Autístico/tratamento farmacológico , Transtornos Globais do Desenvolvimento Infantil/tratamento farmacológico , Suplementos Nutricionais , Magnésio , Vitamina B 6 , Adulto , Transtorno Autístico/fisiopatologia , Cálcio/sangue , Criança , Transtornos Globais do Desenvolvimento Infantil/fisiopatologia , Pré-Escolar , Feminino , Humanos , Lactente , Magnésio/administração & dosagem , Magnésio/sangue , Magnésio/uso terapêutico , Masculino , Vitamina B 6/administração & dosagem , Vitamina B 6/uso terapêutico
6.
Electromyogr Clin Neurophysiol ; 38(6): 367-70, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9783123

RESUMO

This prospective study was undertaken on 190 subjects who had no prior central or peripheral nerve supply pathology and where the value of the sacral reflex latency was compared by age and sex in order to determine precise norms. There were 90 men whose age averaged 56.9 +/- 13 years and 100 women with an average age of 54 +/- 13.1. The reflex was obtained by stimulating the dorsal nerve of the penis and the clitoris and taking a reading in the intermediate part of the external anal sphincter muscle. An averaging technique was used (over 30 stimulation occurrences). The average intensity of the stimulation was 15 mA. The value of the stimulus reaction latency taken at the positive peak was analyzed statistically. The average value was 37.6 +/- 5.36 ms in male subjects and 46.6 +/- 8.08 in female subjects. In men, values varied from 36.6 +/- 4.26 ms at under 35 years of age and reached 42 +/- 3.52 ms at over 75 years. In women, values varied from 37.33 +/- 7.69 ms at under 35 years to 55.6 +/- 4.39 ms at over 75 years of age. In a previous article we discussed ageing features in nerves and muscles. These features are largely responsible for the occurrence of static pelvic problems. The purpose of this study is to compare the sacral reflex latency by sex and age in normal subjects.


Assuntos
Tempo de Reação/fisiologia , Reflexo Abdominal/fisiologia , Adulto , Fatores Etários , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores Sexuais
7.
Electromyogr Clin Neurophysiol ; 38(8): 491-6, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9842484

RESUMO

This study was a prospective study, it was undertaken on 172 subjects who had no prior central or peripheral nerve supply pathology and who had not an antecedent of anal surgery. The subjects had a normal value of the sacral reflex latency to be included in this study. In this population the value of the pudendal motor nerve latency was compared by age and sex in order to determine precise norms. There was 92 men whose age adveraged 36 +/- 14.57 years and 80 women with an average age of 55.03 +/- 15.7. The motor latency was obtained by stimulating the nerve by rectal or vaginal tuch-near the sciatic spine with a St Mark's electrod and taking a reading in the intemediate part of the external anal sphincter muscle. The intensity of the stimulation was 70 to 80 mA. The stimulation and the recording was repeteded five both on each side and the shorter latency whose choised. The value of the motor latency taken at the positive peak was analysed statiscally. The average value was 5.52 +/- 1.9 ms on right pudendal nerve and 5.74 +/- 1.6 ms on the left in male subjects and 6.16 +/- 1.8 in the right pudendal nerve and 6.42 +/- 1.96 on the left in female subjects. The values on right pudendal nerve latency varied from 4.9 +/- 1.28 ms in men and 4.76 +/- 1.6 ms. in women at under 28 years and to 5.06 +/- 2.06 ms in men and 7.7 +/- 1.8 ms in women at over 70 years. The values on the left side varied from 5.53 +/- 1.5 ms in men and 4.78 +/- 1.35 ms in women at under 28 years and to 5.06 +/- 2.06 ms in men and 8.47 +/- 1.95 ms in women at over 70 years. In men population, the value of the motor latency of the pudendal nerve is not correlated with age. In women population, the value is correlated with age.


Assuntos
Neurônios Motores/fisiologia , Nervos Periféricos/fisiologia , Período Refratário Eletrofisiológico/fisiologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Canal Anal/inervação , Eletrofisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores Sexuais
8.
Acupunct Electrother Res ; 9(4): 195-201, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6152510

RESUMO

Stimulation of Jing points at the hand, evokes sensory potentials measurable at the arm on the acupuncture points located above the corresponding nerve courses. Seven normal subjects were studied. The better electrical permeability on the Chinese point is confirmed. Only one impulse allows obtaining of a response through fibres belonging to group II, but the averaging of 32 to 256 response samples is necessary to give evidence of the fibres belonging to groups III and IV. Acupuncture sensation (De Qi) appears as a consequence of correct stimulation of an acupuncture point, that is of the various structures in relation to it.


Assuntos
Terapia por Acupuntura , Potenciais Somatossensoriais Evocados , Mãos/inervação , Nervos Periféricos/fisiologia , Adulto , Braço/inervação , Estimulação Elétrica , Humanos , Condução Nervosa
9.
Rev Mal Respir ; 30(1): 77-80, 2013 Jan.
Artigo em Francês | MEDLINE | ID: mdl-23318194

RESUMO

INTRODUCTION: Acute respiratory distress syndrome caused by Mycoplasma pneumoniae infection has rarely been described. OBSERVATION: We report a case of community-acquired pneumonia occurring in a patient with Down's syndrome. Persisting hypoxemia raised the questions of nosocomial pneumonia, of the occurrence of a fibrosing alveolitis or of the resistance of the strain to macrolides. After a long period of very severe respiratory impairment, the evolution was progressively favourable and the patient was discharged from ICU with full respiratory recovery 43 days after admission. CONCLUSION: Acute respiratory distress syndrome caused by M. pneumoniae infection is rare but must be considered when the appropriate clinical and radiological pattern occurs. The question of the susceptibility of the strain to macrolides has to be raised in some circumstances.


Assuntos
Resistência Microbiana a Medicamentos , Pneumonia por Mycoplasma/complicações , Síndrome do Desconforto Respiratório/etiologia , Adulto , Infecções Comunitárias Adquiridas/complicações , Infecções Comunitárias Adquiridas/diagnóstico , Infecções Comunitárias Adquiridas/diagnóstico por imagem , Síndrome de Down/complicações , Síndrome de Down/diagnóstico por imagem , Resistência Microbiana a Medicamentos/fisiologia , Feminino , Humanos , Unidades de Terapia Intensiva , Mycoplasma pneumoniae/fisiologia , Pneumonia por Mycoplasma/diagnóstico , Pneumonia por Mycoplasma/diagnóstico por imagem , Radiografia Torácica , Síndrome do Desconforto Respiratório/diagnóstico , Síndrome do Desconforto Respiratório/diagnóstico por imagem
10.
Theor Appl Genet ; 64(3): 223-30, 1983 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24264949

RESUMO

Plants were regenerated from axenic plantlets by mesophyll protoplast culture, without mutagenic treatment. Two different lines of Nicotiana sylvestris were used: an original line, and a diploid androgenetic line derived from it. The regenerated plants were either diploid and phenotypically similar to their respective protoplast source line, or tetraploid. Genetic studies carried out on several diploid regenerated plants revealed genetic variability. Eight of 13 selfed progenies of plants regenerated from the original line, and 1 of 8 selfed progenies of plants regenerated from the androgenetic line, produced new mutant phenotypes never observed in the protoplast source lines. Two plants regenerated from the same protoplast-derived callus produced different mutations. Selfed progenies without a recognizable mutant phenotype were also different from their respective protoplast source line for quantitative characters; protoplast culture induced a depressive effect on the size of plants derived from protoplasts at younger and older stages of development. The origin of this depression and of the mutations is discussed.

11.
Theor Appl Genet ; 90(6): 803-10, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-24172922

RESUMO

Fourteen enzyme systems were analysed in leaf parenchyma of nine native and introduced populations of teak. These enzyme systems were encoded by 20 putative loci of which 18 were polymorphic. Populations showed a general lack of heterozygosity (average FIS = 0.11). On average over the 18 polymorphic loci, the genetic differentiation among provenances varied according to the estimator: 0.09 for GST, 0.12 for FST and 0.19 for δ. The cluster analysis showed two main gene pools, the first consisted of the Indian provenances and the second of African, Indonesian and Thai provenances. Genetic distances among populations of the same group were similar, and lower than the genetic distances between populations from different groups. The factorial analysis on genotypes of seedlings also showed the same geographic differentiation into two major groups. The possible natural distribution of teak in Java is discussed.

12.
Bull Assoc Anat (Nancy) ; 67(198): 331-6, 1983 Sep.
Artigo em Francês | MEDLINE | ID: mdl-6675746

RESUMO

A bilateral study for locating the dorsal root filaments of specific nerves was accomplished from the twelfth thoracic to the coccygeal level and this using 26 fetal and 8 adult specimens. After laminectomy from the thoracic to coccygeal levels, incision of the dural sac permitted visualisation of the dorsal root filaments, the successive rootlets corresponding to each segmental level (T12 to Co1 ) were counted with the aid of a binocular microscope where they penetrated the spinal medulla at the posterior sulcus. Statistical evaluation shows that for each dorsal nerve the average number of root filaments is greater on the right compared with the left. Numbering the dorsal nerve root filaments in the cephalo -caudal direction allows to assert with 99% probability up to the L5 level and with 95% probability up to the S1 level that one is at a given spinal level of the respective segmental range; caudal-cephalic direction numbering permits to affirm with 99% probability up to the S1 level and 95% probability up to the L4 level that one is at a given spinal level of the respective segmental range.


Assuntos
Raízes Nervosas Espinhais/anatomia & histologia , Feto/anatomia & histologia , Humanos , Nervos Torácicos/anatomia & histologia
13.
Bull Assoc Anat (Nancy) ; 65(191): 483-8, 1981 Dec.
Artigo em Francês | MEDLINE | ID: mdl-7344745

RESUMO

The authors have studied the veinous pattern of 30 livers of human foetuses from 190 to 390 mm V.C. The injection-corrosion method was used. The portal and sus-hepatic distribution is more frequently modal than for the adult. The portal anomalies touch more frequently the left branches: drainage of the right para-medial area by the left para-medial vein, agenesis or atrophy of the left segmentary branches. The right branch breaks up into several branches in 51% of the cases. The sus-hepatic anomalies are distinguished by the plurality of the veins. The right middle and inferior veins are present in 70% of the cases. Exceptionally large peripheral anastomoses between portal and sus-hepatic systems are observed.


Assuntos
Fígado/embriologia , Feto/anatomia & histologia , Humanos , Fígado/irrigação sanguínea , Veia Porta/embriologia , Veias/embriologia
14.
Bull Assoc Anat (Nancy) ; 71(214): 11-3, 1987 Sep.
Artigo em Francês | MEDLINE | ID: mdl-3502776

RESUMO

Beginning at the sacral plexus the nerve disposition can be found to follow two modalities: first disposition in 2/3 of all cases having a cranial nerve branch for the elevator portion and a caudal nerve branch for the sphincter portion; second disposition in 1/3 of all cases having a branch divided in its terminal part into 2 ramus branches, one for the elevator portion and one for the sphincter portion. On the average the nerve contains 539 fibers of which 73% are myelinated and 27% non myelinated. The fibrillar content is identical for both branches of either disposition.


Assuntos
Canal Anal/inervação , Canal Anal/embriologia , Feto , Humanos , Plexo Lombossacral/anatomia & histologia , Pessoa de Meia-Idade , Músculos/inervação , Fibras Nervosas/ultraestrutura , Fibras Nervosas Mielinizadas/ultraestrutura , Neurofibrilas/ultraestrutura
15.
Tree Physiol ; 14(2): 201-10, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14967714

RESUMO

We studied the response of nodal segments of Eucalyptus microtheca F.J. Muell. to salt stress in a tissue culture system. Three clones of Eucalyptus microtheca (37, 42 and 43) were grown in vitro under saline conditions (0-140 mM NaCl) for three months. The survival of all three clones decreased with increasing concentrations of NaCl in the medium, but the presence of up to 70 mM NaCl stimulated rooting in Clones 37 and 42. Shoot elongation of Clone 43 was less affected by salt than that of Clones 37 and 42. Leaf growth, expressed as leaf length, was stimulated 40% in Clone 42 and 33% in Clone 43, but was progressively inhibited up to 27% by 70 mM NaCl in Clone 37. Massive accumulation of Na(+) and Cl(-) occurred, especially in Clones 42 and 43 (4000 and 3000 mmol Na(+) kg(DW) (-1), respectively), as the salinity of the culture solution increased, and this was correlated with inhibition of growth. Because of a reduction in the accumulation of K(+) with increasing salinity, the K(+)/Na(+) ratio decreased from a control value of 4.5 to 0.14 in shoots grown in the presence of 140 mM NaCl. The development of techniques for selecting seedlings by monitoring the physiology of shoots in vitro instead of testing whole plants in vivo will provide a relatively simple method of selection for woody trees.

16.
Surg Radiol Anat ; 8(2): 115-9, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3097851

RESUMO

The study was performed using 45 pelvic half section specimens (41 fetal ones and four adults). The macroscopic dissection followed the nerve branches from their spinal roots up to the external anal sphincter. Three nerve branches were found: the anterior ramus arising from the external perineal nerve, the inferior rectal nerve and an independent posterior branch. The anterior and the inferior rectal nerve branches always emerged from the pudendal plexus. The posterior branch arising either from S4 or from the inferior rectal nerve was only found in (31%) of our cases. Five anatomical distributions are described, percentages of every type notified. The fibre content of these nerve bundle branches was evaluated through histological sections using Heidenhain's azan stain and Luxol fast blue. The branches consisted of 2,896 to 2,137 fibres, 20% of them being unmyelinated and 80% containing various myelinated fibres. The nomenclature of these nerve branches has to be debated. The terms of anterior, middle and posterior anal nerves seem more suitable.


Assuntos
Canal Anal/inervação , Adulto , Humanos , Recém-Nascido , Fibras Nervosas/anatomia & histologia , Fibras Nervosas/citologia , Fibras Nervosas Mielinizadas/citologia
17.
Mol Gen Genet ; 222(2-3): 206-10, 1990 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2274025

RESUMO

Male sterile plants appeared in the progeny of three fertile plants obtained after one cycle of protoplast culture from a fertile botanical line and two androgenetic lines of Nicotiana sylvestris. These plants showed the same foliar and floral abnormalities as the cytoplasmic male sterile (cms) mitochondrial variants obtained after two cycles of culture. We show that male sterility in these plants is controlled by three independent nuclear genes, ms1, ms2 and ms3, while no changes can be seen in the mitochondrial genome. However, differences were found between the in organello mitochondrial protein synthesis patterns of male sterile and parent plants. Two reproducible changes were observed: the presence of a new 20 kDa polypeptide and the absence of a 40 kDa one. Such variations were described previously in mitochondrial protein synthesis patterns of the cms lines. Fertile hybrids of male sterile plants showed normal synthesis patterns. The male sterile plants are thus mutated in nuclear genes involved in changes observed in mitochondrial protein synthesis patterns.


Assuntos
Mitocôndrias/metabolismo , Nicotiana/genética , Proteínas de Plantas/biossíntese , Plantas Tóxicas , Clonagem Molecular , Cruzamentos Genéticos , Técnicas de Cultura , DNA Mitocondrial/análise , Eletroforese em Gel de Poliacrilamida , Teste de Complementação Genética , Variação Genética , Protoplastos , Reprodução/genética , Nicotiana/anatomia & histologia
18.
Theor Appl Genet ; 108(8): 1643-9, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-14991107

RESUMO

Hybrids between European and Japanese larches combine the properties of both parental species (drought resistance, canker resistance, stem straightness) and exhibit a fast growth rate. They are produced in seed orchards, generally by natural pollination. Seeds are collected and used for afforestation as interspecific hybrids. However, there are no convenient tests to assess the interspecific hybrid proportion. In the present study, we developed diagnostic molecular markers suitable for the individual identification of hybrids, whatever their developmental stage. Our strategy involved testing a combination of maternally inherited markers from the mitochondrial genome (mtDNA) and paternally inherited markers from the chloroplast genome (cpDNA). Hybrids were then identified by the presence of a mitochondrial sequence inherited from one parental species and a chloroplast sequence inherited from the other parental species. To achieve this aim, markers discriminating both parental species were first sought. Amplifications of mitochondrial and chloroplast sequences were performed using specific PCR primers. After testing 33 primer pairs in combination with nine restriction enzymes, we detected one mitochondrial marker, f13 which was amplified in Japanese larch and absent in European larch, and one chloroplast marker, ll- TaqI which showed different restriction patterns depending on the species. A restriction fragment of 601 bp was obtained in Japanese larch while two fragments of 120 bp and 481 bp were observed in European larch. These patterns were found in all 197 individuals tested from the two pure species. These markers were then used for the evaluation of the hybrid proportion in a seed lot produced from seed orchards; this was assessed as between 43% and 53% depending on the parental species. The male and female parental species could be determined for each progeny.


Assuntos
DNA de Cloroplastos/genética , DNA Mitocondrial/genética , Hibridização Genética/genética , Larix/classificação , Larix/genética , Polimorfismo Genético/genética , Europa (Continente) , Marcadores Genéticos/genética , Genoma de Planta , Japão , Larix/fisiologia , Fenótipo , Doenças das Plantas/genética , Reação em Cadeia da Polimerase
19.
Theor Appl Genet ; 93(8): 1274-81, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24162540

RESUMO

Random Amplified Polymorphic DNAs (RAPD) were used for estimating genetic distances between 12 European larches (Larix decidua) and 12 Japanese larches (L. kaempferi) that were the parents in a factorial mating design. One hundred and eleven fragments were used for establishing genetic distances based on Jaccard's coefficient between parents. Thirteen fragments differentiated the larch species. The genetic distance between individuals of the same species (D J =0.39 in the Japanese larch and 0.45 in the European larch) was lower than the genetic distance between species (D J =0.72). A UPGMA dendrogram based on genetic distances clearly clustered each larch species, confirming the speciation at a molecular level. Correlations between genetic distances of the parents and performances of the hybrid families were established for various quantitative traits. Significant values were found for growth characters and branch insertion angle, which suggested an effect of general heterozygosity level on hybrid traits. These correlations also evolved with tree age: the maximal correlation was noticed on 6-year-old trees for height. The lack of correlation between parental genetic distances and hybrid performances for the other quantitative traits suggested that these characters were controlled by fewer genes. The results of this study show that crosses between genetically distant parents produce hybrids with excellent growth performances; this represents a potential selection criterion of the genitors.

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