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1.
J Laryngol Otol ; 138(2): 184-187, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37615109

RESUMO

OBJECTIVE: This study investigated the psychological status of patients with unilateral or bilateral complete nasal obstruction. METHOD: The study included 49 consecutive cases of unilateral or bilateral complete nasal obstruction. In order to assess participants' personality traits, both groups completed the Personality Belief Questionnaire, State-Trait Anxiety Inventory form, Beck Depression Inventory and Beck Anxiety Inventory. RESULTS: The groups were similar in terms of demographic characteristics. Patients with unilateral or bilateral complete nasal obstruction had higher scores on all the psychological assessments compared with the healthy controls, except for the Beck Anxiety Inventory. Although all personality assessment scores were higher in patients, the only differences that were statistically significant were in the dependent, antisocial and avoidant personality trait scores. CONCLUSION: The psychological conditions of patients with structural deformities that cause nasal obstruction may be affected, and appropriate treatment should be provided to improve their symptoms and quality of life.


Assuntos
Obstrução Nasal , Adulto , Humanos , Obstrução Nasal/diagnóstico , Qualidade de Vida , Ansiedade/etiologia , Ansiedade/psicologia , Depressão/etiologia , Depressão/psicologia
2.
Eur Rev Med Pharmacol Sci ; 27(5 Suppl): 95-100, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37869954

RESUMO

We reviewed the potential benefits of conchal cartilage or Polydioxanone (PDS) foil-empowered nasal cartilage as caudal septal extension grafts (CSEGs). Research methods included searching online databases such as Google, Google Scholar, PubMed, and Proquest Central at Kirikkale University. Use terms like "caudal septal extension grafts," "septal extension grafts," "conchal cartilage," and "PDS foil-empowered nasal cartilage" to find related articles. Due to the anchoring of the lower alar cartilage to the nasal septum, the results of a CSEG rhinoplasty are relatively stable over the long term. They can be adjusted independently by the rhinoplasty surgeon. Over time, the skin and soft tissue envelope contract and a downward force for these grafts develops. It allows for independent regulation of projection and rotation, unlike conventional columellar strut procedures and lateral crural steal techniques. Inadequate cartilage may need conchal or costal cartilage, depending on the application and the need for projection and counter rotation. Costal cartilage transplant outperformed conchal cartilage graft in a rabbit model regarding tip projection and angle relapse rate. Three-patient case series show that PDS foil-enhanced nasal cartilage led to septal cartilage loss. However, other research draws a different result, finding that PDS foil-enhanced nasal cartilage prevented growth inhibition in the developing nasal septum following septoplasty, and reduced late problems in animals. The caudal septal extension grafts should prioritize septum cartilage if it is readily available, of adequate size, and with sufficient strength. If this is not possible, PDS foil-enhanced nasal cartilage fragments or conchal cartilage could be used as a backup. PDS foil will maintain the integrity and stability of the implanted cartilage. Due to its strength, stability, and convenient location, conchal cartilage will serve as the second donor site.


Assuntos
Cartilagens Nasais , Rinoplastia , Humanos , Animais , Coelhos , Cartilagens Nasais/transplante , Septo Nasal/cirurgia , Rinoplastia/métodos , Próteses e Implantes , Pele , Estudos Retrospectivos
3.
Epilepsia ; 64(4): 875-887, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36661376

RESUMO

OBJECTIVE: Transcranial direct current stimulation (tDCS) has been advocated for various neurological conditions, including epilepsy. A 1-4-mA cathodal current applied to the scalp over a seizure focus can reduce spikes and seizures. This series of four patients with focal status epilepticus is among the first case series to demonstrate benefit of tDCS in the critical care setting. METHODS: Patients in the intensive care unit were referred for tDCS treatment when focal status epilepticus or clinically relevant lateralized periodic discharges did not resolve with conventional antiseizure medications and anesthetics. Battery-powered direct cathodal current at 2 mA was delivered by an ActivaDose (Caputron) tDCS device via a saline-soaked sponge on the scalp over the seizure focus. Anode was on the contralateral forehead or shoulder. Treatment was for 30 min, repeated twice in a day, then again 1-4 times more over the next few days. RESULTS: Three females and one male, aged 34-68 years, were treated. Etiologies of status epilepticus were posterior reversible encephalopathy syndrome in association with immunosuppressants for a liver transplant, perinatal hypoxic-ischemic injury, a prior cardioembolic parietal stroke, and central nervous system lupus. tDCS led to significant reduction of interictal spikes (.78 to .38/s, p < .0001) in three cases and electrographic seizures (3.83/h to 0/h, p < .001) in two cases. Medication reductions were enabled in all cases subsequent to tDCS. The only side effect of tDCS was transient erythema under the sponge in one case. Two patients died of causes unrelated to tDCS, one was discharged to a nursing home, and one became fully responsive as seizures were controlled with tDCS. SIGNIFICANCE: Spikes and electrographic seizure frequency significantly improved within 1 day of tDCS. Results are potentially confounded by multiple ongoing changes in medications and treatments. These results might encourage further investigation of tDCS in the critical care setting, but verification by controlled studies will be required.


Assuntos
Epilepsia Parcial Contínua , Síndrome da Leucoencefalopatia Posterior , Estado Epiléptico , Estimulação Transcraniana por Corrente Contínua , Feminino , Humanos , Masculino , Estimulação Transcraniana por Corrente Contínua/efeitos adversos , Estimulação Transcraniana por Corrente Contínua/métodos , Alta do Paciente , Síndrome da Leucoencefalopatia Posterior/etiologia , Eletroencefalografia , Convulsões/etiologia , Estado Epiléptico/terapia , Estado Epiléptico/etiologia , Cuidados Críticos
4.
Eur Rev Med Pharmacol Sci ; 26(17): 6121-6128, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36111914

RESUMO

OBJECTIVE: We evaluated how efficacious indomethacin, at two different doses, is in the treatment of an experimental model of sinusitis in rats. MATERIALS AND METHODS: Twenty-one Wistar albino rats (all male) were sorted at random into one of three groups: 1st group (n=7) was placebo. 2nd group (n=7). These rats had sinusitis induced experimentally, following indomethacin 3 mg/kg, 5 days was administered to them. 3rd group (n=7). These rats had sinusitis induced experimentally, following indomethacin 6 mg/kg, 5 days was administered to them. The animals' sinonasal mucosae were examined histopathologically by standard light microscopy. RESULTS: Experimental sinusitis was observed in the 2nd and 3rd groups, but not in the rats administered a placebo. Although the inflammatory features of sinusitis were found to be significantly decreased in the animals administered indomethacin 3 mg/kg (the 2nd group), this anti-inflammatory effect was even greater in the 3rd group, where indomethacin 6 mg/kg had been administered. Indomethacin at either dose was superior to placebo in reducing inflammatory features of sinusitis. CONCLUSIONS: Topical use of indomethacin nasal drops decreased the inflammatory features in experimentally induced acute sinusitis. Moreover, a higher dose of indomethacin (6 mg/kg) was more efficacious than a lower dose (3 mg/kg). The present study is valuable as an initial step in showing the need to undertake human trials to see the effect of indomethacin nasal drops on sinusitis in humans. In acute rhinosinusitis, the use of topical anti-inflammatory drops may help to decrease the symptoms and may be used adjunctively with antibiotic treatment.


Assuntos
Indometacina , Sinusite , Doença Aguda , Animais , Antibacterianos/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Indometacina/farmacologia , Indometacina/uso terapêutico , Masculino , Ratos , Ratos Wistar , Sinusite/tratamento farmacológico
5.
J Clin Neurophysiol ; 2022 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-36007069

RESUMO

PURPOSE: To investigate the prognostic value of a simple stratification system of electroencephalographical (EEG) patterns and spectral types for patients after cardiac arrest. METHODS: In this prospectively enrolled cohort, using manually selected EEG segments, patients after cardiac arrest were stratified into five independent EEG patterns (based on background continuity and burden of highly epileptiform discharges) and four independent power spectral types (based on the presence of frequency components). The primary outcome is cerebral performance category (CPC) at discharge. Results from multimodal prognostication testing were included for comparison. RESULTS: Of a total of 72 patients, 6 had CPC 1-2 by discharge, all of whom had mostly continuous EEG background without highly epileptiform activity at day 3. However, for the same EEG background pattern at day 3, 19 patients were discharged at CPC 3 and 15 patients at CPC 4-5. After adding spectral analysis, overall sensitivity for predicting good outcomes (CPC 1-2) was 83.3% (95% confidence interval 35.9% to 99.6%) and specificity was 97.0% (89.5% to 99.6%). In this cohort, standard prognostication testing all yielded 100% specificity but low sensitivity, with imaging being the most sensitive at 54.1% (36.9% to 70.5%). CONCLUSIONS: Adding spectral analysis to qualitative EEG analysis may further improve the diagnostic accuracy of EEG and may aid developing novel measures linked to good outcomes in postcardiac arrest coma.

6.
Bioelectron Med ; 4: 5, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-32232081

RESUMO

BACKGROUND: Vagus nerve stimulation (VNS) is a promising therapy for many neurologic and psychiatric conditions. However, determining stimulus parameters for individual patients is a major challenge. The traditional method of titrating stimulus intensity based on patient perception produces highly variable responses. This study explores using the vagal response to measure stimulation dose and predict physiological effect. Clinicians are investigating the use of VNS for heart failure management, and this work aims to correlate cardiac measures with vagal fiber activity. RESULTS: By recording vagal activity during VNS in rats and using regression analysis, we found that cardiac activity across all animals was best correlated to the activation of a specific vagal fiber group. With conduction velocities ranging from 5 to 10 m/s, these fibers are classified as B fibers (using the Erlanger-Gasser system) and correspond to vagal parasympathetic efferents. CONCLUSIONS: B fiber activation can serve as a standardized, objective measure of stimulus dose across all subjects. Tracking fiber activation provides a more systematic way to study the effects of VNS and in the future, may lead to a more consistent method of therapy delivery.

7.
Biomicrofluidics ; 10(5): 054116, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27795748

RESUMO

In pre-clinical safety studies, drug-induced vascular injury (DIVI) is defined as an adverse response to a drug characterized by degenerative and hyperplastic changes of endothelial cells and vascular smooth muscle cells. Inflammation may also be seen, along with extravasation of red blood cells into the smooth muscle layer (i.e., hemorrhage). Drugs that cause DIVI are often discontinued from development after considerable cost has occurred. An in vitro vascular model has been developed using endothelial and smooth muscle cells in co-culture across a porous membrane mimicking the internal elastic lamina. Arterial flow rates of perfusion media within the endothelial chamber of the model induce physiologic endothelial cell alignment. Pilot testing with a drug known to cause DIVI induced extravasation of red blood cells into the smooth muscle layer in all devices with no extravasation seen in control devices. This engineered vascular model offers the potential to evaluate candidate drugs for DIVI early in the discovery process. The physiologic flow within the co-culture model also makes it candidate for a wide variety of vascular biology investigations.

9.
IEEE Trans Neural Syst Rehabil Eng ; 23(6): 936-45, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25872215

RESUMO

We demonstrate an alternative method of designing electrical stimuli-termed burst modulation--for producing different patterns of nerve fiber recruitment. By delivering electrical charge in bursts of "pulsons"--miniature pulses-instead of as long continuous pulses, our method can optimize the waveform for stimulation efficiency and fiber selectivity. In our in vivo validation experiments, while maintaining C fibers of the rat vagus nerve at ∼ 50% activation with different waveforms, the burst-modulated waveform produced 11% less A fiber activation than the standard rectangular pulse waveform (rectangular: 50.8±1.5% of maximal A response, mean ± standard error of the mean; burst-modulated: 39.8 ±1.3%), which equates to a 20% reduction in A fiber response magnitude. In addition, the burst-modulated waveform required 45% less stimulus charge per phase to maintain 50% C fiber activation (rectangular: 20.7 ±0.86 µC; burst-modulated: 11.3 ±0.41 µC ). Burst-modulated waveforms produced consistent patterns of fiber recruitment within and across animals, which indicate that our methods of stimulus design and response analysis provide a reliable way to study neurostimulation and deliver therapy.


Assuntos
Estimulação Elétrica/instrumentação , Estimulação Elétrica/métodos , Fibras Nervosas/fisiologia , Algoritmos , Animais , Terapia por Estimulação Elétrica/métodos , Eletrodos Implantados , Feminino , Fibras Nervosas Amielínicas/fisiologia , Ratos , Ratos Long-Evans , Recrutamento Neurofisiológico/fisiologia , Nervo Vago/citologia , Nervo Vago/fisiologia , Análise de Ondaletas
11.
IEEE Trans Neural Syst Rehabil Eng ; 23(4): 562-71, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25706720

RESUMO

Neural recording and stimulation have great clinical potential. Long-term neural recording remains a challenge, however, as implantable electrodes eventually fail due to the adverse effects of the host tissue response to the indwelling implant. Astrocytes and microglia attempt to engulf the electrode, increasing the electrical impedance between the electrode and neurons, and possibly pushing neurons away from the recording site. Faster insertion speed, finer tip geometry, smaller size, and lower material stiffness all seem to decrease damage caused by insertion and reduce the intensity of the tissue response. However, electrodes that are too small result in buckling, making insertion impossible. In this paper, we assess the viability of high-speed (27.8 m/s) deployment of 25 µm, ferromagnetic microelectrodes into rat brain. To characterize functionality of magnetically inserted electrodes, 4 Long-Evans rats were implanted for 31 days with impedance measurements and neural recordings taken daily. Performance was compared to 150 µm diameter PlasticsOne electrodes since 25 µm electrodes buckled during "slow speed" insertion. Platinum-iron magnetically inserted electrodes resolved single unit activity throughout the duration of the study in one rat, and saw no significant change (p=0.970) in impedance (4.54% increase) from day 0 (Z0 ≈ 144 kΩ,Z31 ≈ 150 kΩ). These findings provide a proof-of-concept for magnetic insertion as a viable insertion method that enables nonbuckling implantation of small (25 µm) microelectrodes, with potential for neural recording applications.


Assuntos
Eletrodos Implantados , Neurônios , Animais , Astrócitos , Encéfalo/anatomia & histologia , Impedância Elétrica , Desenho de Equipamento , Falha de Equipamento , Magnetismo , Microeletrodos , Microglia , Ratos , Ratos Long-Evans
13.
IEEE Trans Neural Syst Rehabil Eng ; 23(3): 475-84, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25167554

RESUMO

Electrical vagus nerve stimulation is a treatment alternative for many epileptic and depressed patients whose symptoms are not well managed with pharmaceutical therapy. However, the fixed stimulus, open loop dosing mechanism limits its efficacy and precludes major advances in the quality of therapy. A real-time, responsive form of vagus nerve stimulation is needed to control nerve activation according to therapeutic need. This personalized approach to therapy will improve efficacy and reduce the number and severity of side effects. We present autonomous neural control, a responsive, biofeedback-driven approach that uses the degree of measured nerve activation to control stimulus delivery. We demonstrate autonomous neural control in rats, showing that it rapidly learns how to most efficiently activate any desired proportion of vagal A, B, and/or C fibers over time. This system will maximize efficacy by minimizing patient response variability and by minimizing therapeutic failures resulting from longitudinal decreases in nerve activation with increasing durations of treatment. The value of autonomous neural control equally applies to other applications of electrical nerve stimulation.


Assuntos
Biorretroalimentação Psicológica , Próteses Neurais , Medicina de Precisão/instrumentação , Estimulação do Nervo Vago/instrumentação , Algoritmos , Animais , Artefatos , Desenho de Equipamento , Fibras Nervosas/fisiologia , Fibras Nervosas Amielínicas/fisiologia , Medicina de Precisão/métodos , Ratos , Estimulação do Nervo Vago/métodos
14.
J Obstet Gynaecol ; 35(3): 225-8, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25140392

RESUMO

The aim of this study was to evaluate whether pregnant women with fetal growth restriction (FGR) have higher plasma neopterin and C-reactive protein (CRP) concentrations compared with those with uncomplicated pregnancy. A total of 34 pregnant women with FGR and 62 patients with uncomplicated pregnancy were included. Neopterin and CRP levels were measured at the time of diagnosis. The primary outcome of this study was to compare the neopterin and CRP levels in pregnant women with FGR and those with uncomplicated pregnancies. The secondary outcome of our study was to evaluate the correlation between fetal birth weight and maternal neopterin levels. The serum neopterin levels were significantly elevated in pregnant women with FGR (22.71 ± 7.70 vs 19.15 ± 8.32). However, CRP was not elevated in pregnant women with FGR (7.47 ± 7.59 vs 5.29 ± 3.58). These findings support the hypothesis that pregnancy with FGR is associated with a marked increase in macrophage activation and the natural immune system.


Assuntos
Proteína C-Reativa/metabolismo , Retardo do Crescimento Fetal/sangue , Neopterina/sangue , Adulto , Peso ao Nascer , Estudos de Casos e Controles , Feminino , Humanos , Gravidez , Adulto Jovem
17.
J Neurosurg ; 120(4): 997-1005, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24460492

RESUMO

OBJECT: There is increasing interest in deep brain stimulation (DBS) for the treatment of addiction. Initial testing must be conducted in animals, and the alcohol-preferring (P) rat meets the criteria for an animal model of alcoholism. This study is composed of 2 experiments designed to examine the effects of 1) pharmacological inactivation and 2) DBS of the nucleus accumbens shell (AcbSh) on the consumption of alcohol by P rats. METHODS: In the first experiment, the effects of reversible inactivation of the AcbSh were investigated by administering intracranial injections of γ-aminobutyric acid (GABA) agonists. Bilateral microinjections of drug were administered to the AcbSh in P rats (8-10 rats/group), after which the animals were placed in operant chambers containing 2 levers--one used to administer water and the other to administer 15% EtOH--to examine the acquisition and maintenance of oral EtOH self-administration. In the second experiment, a DBS electrode was placed in each P rat's left AcbSh. The animals then received 100 or 200 µA (3-4 rats/group) of DBS to examine the effect on daily consumption of oral EtOH in a free-access paradigm. RESULTS: In the first experiment, pharmacological silencing of the AcbSh with GABA agonists did not decrease the acquisition of EtOH drinking behavior but did reduce EtOH consumption by 55% in chronically drinking rats. Similarly, in the second experiment, 200 µA of DBS consistently reduced EtOH intake by 47% in chronically drinking rats. The amount of EtOH consumption returned to baseline levels following termination of therapy in both experiments. CONCLUSIONS: Pharmacological silencing and DBS of the AcbSh reduced EtOH intake after chronic EtOH use had been established in rodents. The AcbSh is a neuroanatomical substrate for the reinforcing effects of alcohol and may be a target for surgical intervention in cases of alcoholism.


Assuntos
Consumo de Bebidas Alcoólicas/terapia , Estimulação Encefálica Profunda , Etanol/administração & dosagem , Núcleo Accumbens/fisiopatologia , Autoadministração , Consumo de Bebidas Alcoólicas/fisiopatologia , Animais , Baclofeno/farmacologia , Condicionamento Operante/efeitos dos fármacos , Condicionamento Operante/fisiologia , Feminino , Agonistas GABAérgicos/farmacologia , Muscimol/farmacologia , Núcleo Accumbens/efeitos dos fármacos , Ratos , Recompensa
18.
Br J Dermatol ; 169(5): 1066-70, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23889284

RESUMO

BACKGROUND: Psoriasis vulgaris is an inflammatory disease characterized by epidermal hyperproliferation, leucocyte adhesion molecule expression and leucocyte infiltration. Psoriasis is associated with an increased risk of cardiovascular disease. Endothelial dysfunction is widely regarded as being the initial process in the development of atherosclerosis. Human endothelial cell-specific molecule-1 (endocan) is a novel human endothelial cell-specific molecule. Previous studies suggested that endocan may be a novel endothelial dysfunction marker. OBJECTIVES: To investigate the relationship between serum levels of endocan and both cardiovascular risk and disease activity in patients with psoriasis vulgaris. METHODS: A total of 29 patients with psoriasis vulgaris and 35 control subjects were included in the study. Endocan, high-sensitivity C-reactive protein (hsCRP) and carotid artery intima-media thickness (cIMT) were measured in all subjects. RESULTS: Serum endocan levels were significantly different between the two groups (P < 0.001). In patients with psoriasis, serum endocan levels correlated with Psoriasis Area and Severity Index, hsCRP and cIMT (r = 0.477, P = 0.009; r = 0.484, P = 0.008; r = 0.408, P = 0.02, respectively). CONCLUSIONS: Circulating endocan may represent a new marker that correlates with cardiovascular risk as well as the severity of disease in patients with psoriasis vulgaris. Endocan may be a surrogate endothelial dysfunction marker and may have a functional role in endothelium-dependent pathological disorders. Whether endocan levels could become a treatment target merits further investigation.


Assuntos
Doenças Cardiovasculares/etiologia , Proteínas de Neoplasias/metabolismo , Proteoglicanas/metabolismo , Psoríase/sangue , Adulto , Biomarcadores/metabolismo , Proteína C-Reativa/metabolismo , Doenças Cardiovasculares/sangue , Espessura Intima-Media Carotídea , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Curva ROC , Fatores de Risco
19.
Med Oncol ; 29(2): 734-41, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21547408

RESUMO

The aim of this study was to evaluate the expressions of oncoproteins and to correlate the results with clinicopathologic parameters in papillary thyroid carcinoma (PTC). Papillary thyroid cancer (PTC) is the most common form and accounts for about 80% of all thyroid cancers. Although PTC generally has a good prognosis, some patients suffer from local recurrence and/or distant metastasis. Oncogenes have reported to be related not only in carcinogenesis but also in tumor prognosis, tumor type, differentiation and site of tumor in epithelial malignant tumors such as thyroid, breast, ovarian, and stomach cancer. This study was planned retrospectively and was performed in 87 patients (47 PTC, 40 benign lesions). The data of clinicopathologic parameters and tissue samples were collected from the archives. Sections stained with H&E were evaluated for each case and after confirming the diagnosis of PTC, oncoprotein expressions were determined by immunohistochemical analysis. The differences of oncoprotein expressions in PTC compared with control group were statistically significant. Cyclin D1 and p53 expressions were significantly increased in PTC. The expressions of bcl-2 and c-erbB-2 in PTC were found as increased, but the correlation between these proteins and poor prognostic parameters were not significant. We suggest that increased expressions of cyclin D1 and p53 could be used as prognostic factors in patients with PTC.


Assuntos
Adenocarcinoma de Células Claras/metabolismo , Biomarcadores Tumorais/metabolismo , Carcinoma Papilar/metabolismo , Carcinoma/metabolismo , Proteínas Oncogênicas/metabolismo , Neoplasias da Glândula Tireoide/metabolismo , Adenocarcinoma de Células Claras/patologia , Adulto , Idoso , Carcinoma/patologia , Carcinoma Papilar/patologia , Ciclina D1/metabolismo , Feminino , Seguimentos , Genes erbB , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/patologia , Proteína Supressora de Tumor p53/metabolismo , Adulto Jovem
20.
Mol Ecol ; 19(24): 5452-68, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21073588

RESUMO

The Strait of Gibraltar (SG) is reputed for being both a bridge and a geographic barrier to biological exchanges between Europe and Africa. Major genetic breaks associated with this strait have been identified in various taxa, but it is unknown whether these disjunctions have been produced simultaneously or by independent biogeographic processes. Here, the genetic structure of five conifers distributed on both sides of the SG was investigated using mitochondrial (nad1 b/c, nad5-1, nad5-4 and nad7-1) and chloroplast (Pt1254, Pt15169, Pt30204, Pt36480, Pt71936 and Pt87268) DNA markers. The distribution of genetic variation was partially congruent between types of markers within the same species. Across taxa, there was a significant overlapping between the SG and the genetic breaks detected, especially for the four Tertiary species surveyed (Abies pinsapo complex, Pinus nigra, Pinus pinaster and Taxus baccata). For most of these taxa, the divergence of populations across the SG could date back to long before the Pleistocene glaciations. However, their strongly different cpDNA G(ST) and R(ST) values point out that they have had dissimilar population histories, which might include contrasting amounts of pollen-driven gene flow since their initial establishment in the region. The fifth species, Pinus halepensis, was genetically depauperated and homogenous on both sides of the SG. A further analysis of nuclear DNA sequences with coalescent-based isolation with migration models suggests a Pleistocene divergence of P. halepensis populations across the SG, which is in sharp contrast with the pre-Pleistocene divergence dates obtained for P. pinaster. Altogether, these results indicate that the genetic breaks observed across this putative biogeographical barrier have been produced by independent evolutionary processes related to the biological history of each individual species instead of a common vicariant phenomenon.


Assuntos
Filogeografia , Traqueófitas/genética , DNA de Cloroplastos/genética , DNA Mitocondrial/genética , Variação Genética/genética , Gibraltar , Traqueófitas/classificação
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