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1.
Life (Basel) ; 13(10)2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37895441

RESUMO

For decades, needling interventions have been performed based on manual palpation and anatomic knowledge. The increasing use of real-time ultrasonography in clinical practice has improved the accuracy and safety of needling techniques. Although currently ultrasound-guided procedures are routinely used for patellar tendon pathology, e.g., during percutaneous electrolysis, the accuracy of these procedures is still unknown. This study used a cadaveric model to compare and evaluate both the accuracy and safety of ultrasound-guided and palpation-guided needling techniques for the patellar tendon. A total of five physical therapists performed a series of 20 needle insertion task each (n = 100), 10 insertions based on manual palpation (n = 50) and 10 insertions guided with ultrasound (n = 50) to place a needle along the interface between the patellar tendon and Hoffa's fat pad. All procedures were performed on cryopreserved knee specimens. Distance to the targeted tissue, time of the procedure, accurate rate of insertions, number of passes, and unintentional punctured structures between both applications (with and without ultrasound guiding) were compared. The results revealed higher accuracy (100% vs. 80%), a lower distance from needle to the targeted tissue (0.25 ± 0.65 vs. 2.5 ± 1.9 mm), longer surface of contact with the needle (15.5 ± 6.65 vs. 4.7 ± 7.5 mm), and a lower frequency of patellar tendon puncture (16% vs. 52%, p < 0.001) with the ultrasound-guided procedure as opposed to palpation-guided one. Nevertheless, the ultrasound-guided procedure took longer (54.8 ± 26.8 vs. 23.75 ± 15.4 s) and required more passes (2.55 ± 1.9 vs. 1.5 ± 0.95) to be conducted than the palpation-guided procedure (all, p < 0.001). According to these findings, the accuracy of invasive procedures applied on the patellar tendon is higher when conducted with ultrasound guidance than when conducted just on manual palpation or anatomical landmark. These results suggest that ultrasound could improve the clinical application of invasive procedures at the fat-patellar tendon interface. Due to the anatomical features of the targeted tissue, some procedures require this precision, so the use of ultrasound is recommended.

2.
Pain Res Manag ; 2023: 1523834, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37664417

RESUMO

The purpose of this systematic review and meta-analysis was to assess the short-, mid-, and long-term effectiveness of dry needling in improving pain and functional capacity of patients with chronic neck pain. Search strategy was performed on PubMed, Web of Science, Scopus, PEDro, and Cochrane Library Plus biomedical databases. The risk of bias was assessed using the RoB2 tool. Randomised controlled clinical trials in which at least 1 of the groups received dry needling were included. 662 studies were found; 14 clinical trials were selected for qualitative analysis and 13 for quantitative analysis. The quality of most of the studies included was "high." All the studies reported improvements in cervical pain and/or disability, regardless of the protocol followed and the muscles targeted. No serious adverse effects were reported. Dry needling showed to be more effective when compared with other therapies in both women and men, without differences by sex. When the analysis was carried out by age, patients over 40 years old benefitted more than those below 40 years old. Our meta-analysis supports the use of dry needling to improve pain and functional capacity in patients with chronic neck pain at short- and mid-term intervals.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Agulhamento Seco , Masculino , Humanos , Feminino , Adulto , Cervicalgia/terapia , Bases de Dados Factuais , Músculos
3.
Healthcare (Basel) ; 11(11)2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37297743

RESUMO

Percutaneous electrical stimulation has been performed for years with only the assistance of anatomical landmarks. The development of real-time ultrasonography guidance has improved the precision and safety of these percutaneous interventions. Despite ultrasound-guided and palpation-guided procedures being performed routinely for targeting nerve tissues in the upper extremity, the precision and safety of these techniques are unknown. The aim of this cadaveric study was to determine and compare the precision and safety of ultrasound-guided versus palpation-guided needling procedure with and without the handpiece of the ulnar nerve on a cadaveric model. Five physical therapists performed a series of 20 needle insertion tasks each (n = 100), 10 palpation-guided (n = 50) and 10 ultrasound-guided (n = 50) on cryopreserved specimens. The purpose of the procedure was to place the needle in proximity to the ulnar nerve at the cubital tunnel. The distance to target, time performance, accurate rate, number of passes, and unintentional puncture of surrounding structures were compared. The ultrasound-guided procedure was associated with higher accuracy (66% vs. 96%), lower distance from needle to the target (0.48 ± 1.37 vs. 2.01 ± 2.41 mm), and a lower frequency of perineurium puncture (0% vs. 20%) when compared with the palpation-guided procedure. However, the ultrasound-guided procedure required more time (38.33 ± 23.19 vs. 24.57 ± 17.84 s) than the palpation-guided procedure (all, p < 0.001). Our results support the assumption that ultrasound guidance improves the accuracy of needling procedures on the ulnar nerve at the cubital tunnel when compared with palpation guidance.

4.
Am J Phys Med Rehabil ; 102(12): 1091-1096, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37205741

RESUMO

OBJECTIVES: The aims of the study are to analyze and describe the accuracy of an ultrasound-guided approach to target the L5 root in cadaveric specimens and evaluate whether gender differences exist. DESIGN: A cross-anatomical study on 40 cadaver L5 nerve roots was performed. A needle was introduced until contacting the L5 nerve root using ultrasound guidance. After that, specimens were frozen and studied by a cross-anatomical view to see the needle's path. The angulation, length, distance from the vertebral spine, the relevant ultrasound anatomical references, and the accuracy of the procedure were evaluated. RESULTS: The needle tip reached the L5 root at a 72.5% rate. The mean angulation degrees of the needle relative to the skin surface were 75.53 ± 10.17 degrees, the length of the needle inserted was 5.83 ± 0.82 cm, and the distance from the vertebral spine to the point of entry of the needle was 5.39 ± 1.44 cm. CONCLUSIONS: An ultrasound-guided technique can potentially be an accurate technique to perform invasive procedures on the L5 root. There were statistically significant differences between males and females in the length of the needle introduced. If the L5 root is not clearly visualized, ultrasound will not be the technique of choice.


Assuntos
Vértebras Lombares , Raízes Nervosas Espinhais , Masculino , Feminino , Humanos , Raízes Nervosas Espinhais/diagnóstico por imagem , Ultrassonografia , Vértebras Lombares/diagnóstico por imagem , Ultrassonografia de Intervenção/métodos , Cadáver
5.
Artigo em Inglês | MEDLINE | ID: mdl-36497812

RESUMO

Percutaneous needle electrolysis (PNE) consists of the ultrasound-guided application of a galvanic electrical current through a solid filament needle. One proposed therapeutic mechanism for this intervention is a potential thermal effect. The aim of this study was to investigate if the application of PNE induces changes in temperature in different cadaveric musculoskeletal tissues. A repeated measure experimental cadaveric study was designed with 10 cryopreserved knees (5 men, 5 women). Sterile stainless-steel needles of 40 mm length and 0.30 mm caliber were used in this study. An ultrasound-guided needling puncture was performed in the targeted tissue (patellar tendon, infra-patellar fat, and vastus medialis muscle). Additionally, the tip of the needle was placed next to the thermometer sensor at the minimum possible distance without direct contact with it. The temperature differences before and after different applications were measured. The applications were: three applications for 3 s of 3 mA of intensity (3:3:3) when the tendon was the targeted tissue, three applications for 3 s of 1.5 mA of intensity (1.5:3:3) when the fat or muscle was the targeted tissue, and 24 s of 1 mA of intensity (1:24:1) in all tissues. No statistically significant Group*Time interactions were found in any tissue (tendon: F = 0.571, p = 0.459, ŋ2 = 0.03; fat pad: F = 0.093; p = 0.764, ŋ2 = 0.01; muscle: F = 0.681; p = 0.420, ŋ2 = 0.04). Overall, no changes in temperature were observed between both applications in the tendon (3:3:3 vs. 1:24:1) and fat/muscle (1.5:3:3 vs. 1:24:1) tissues. The application of two different percutaneous needle electrolysis protocols did not produce appreciable thermal changes in the tendon, fat, and muscle tissues of human cadavers. The results from the current cadaver study support that a thermal effect should not be considered as a mechanism of clinical action regardless of the targeted human tissue when applying percutaneous needle electrolysis since no changes in temperature after its application were observed.


Assuntos
Eletrólise , Ligamento Patelar , Masculino , Humanos , Feminino , Eletrólise/métodos , Projetos de Pesquisa , Temperatura , Cadáver
6.
Biomed Res Int ; 2021: 9936981, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34189141

RESUMO

BACKGROUND: Cervical radiculopathy is defined as a disorder involving dysfunction of the cervical nerve roots characterised by pain radiating and/or loss of motor and sensory function towards the root affected. There is no consensus on a good definition of the term. In addition, the evidence regarding the effectiveness of manual therapy in radiculopathy is contradictory. OBJECTIVE: To assess the effectiveness of manual therapy in improving pain, functional capacity, and range of motion in treating cervical radiculopathy with and without confirmation of altered nerve conduction. METHODS: Systematic review of randomised clinical trials on cervical radiculopathy and manual therapy, in PubMed, Web of Science, Scopus, PEDro, and Cochrane Library Plus databases. The PRISMA checklist was followed. Methodological quality was evaluated using the PEDro scale and RoB 2.0. tool. RESULTS: 17 clinical trials published in the past 10 years were selected. Manual therapy was effective in the treatment of symptoms related to cervical radiculopathy in all studies, regardless of the type of technique and dose applied. CONCLUSIONS: This systematic review did not establish which manual therapy techniques are the most effective for cervical radiculopathy with electrophysiological confirmation of altered nerve conduction. Without this confirmation, the application of manual therapy, regardless of the protocol applied and the manual therapy technique selected, appears to be effective in reducing chronic cervical pain and decreasing the index of cervical disability in cervical radiculopathy in the short term. However, it would be necessary to agree on a definition and diagnostic criteria of radiculopathy, as well as the definition and standardisation of manual techniques, to analyse the effectiveness of manual therapy in cervical radiculopathy in depth.


Assuntos
Vértebras Cervicais/fisiopatologia , Manipulações Musculoesqueléticas/métodos , Cervicalgia/fisiopatologia , Radiculopatia/fisiopatologia , Ensaios Clínicos como Assunto , Eletromiografia , Humanos , Amplitude de Movimento Articular
7.
J Back Musculoskelet Rehabil ; 34(2): 243-249, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32831191

RESUMO

BACKGROUND: The straight leg raise test (SLR) is one of the most performed physical tests for mechanosensitivity and impairment of the nervous system. According to the anatomy of the tibial nerve, ankle dorsiflexion and eversion movements could be used to perform the tibial neurodynamic test (TNT). To date, no study has documented the normal responses of the TNT. OBJECTIVE: To document normal responses of the TNT in asymptomatic individuals and to investigate influences from sex and leg dominance. METHODS: A cross-sectional study with 44 asymptomatic volunteer subjects, a total of 88 lower limbs, was carried out. The range of motion (ROM), quality, and distribution of sensory responses were recorded. The hip flexion ROM was measured when subjects reported an intensity of their symptoms of 2/10 (P1) and 8/10 (P2). RESULTS: The mean ROM for hip flexion at P1 was 44.22 ± 13.13∘ and 66.73 ± 14.30∘ at P2. Hip flexion was significantly greater at P2 than P1 (p< 0.001). However, it was not different between sex or limbs (p> 0.05). The descriptor of the quality of sensory responses most often used by participants was stretching (88.6% and 87.5% for P1 and P2, respectively) in the popliteal fossa and posterior calf. CONCLUSIONS: This study describes the sensory responses of asymptomatic subjects resulting from the TNT. Our findings indicate that TNT responses are independent of the influence of sex or leg dominance.


Assuntos
Articulação do Quadril/fisiologia , Perna (Membro)/fisiologia , Amplitude de Movimento Articular/fisiologia , Nervo Tibial/fisiologia , Adulto , Estudos Transversais , Feminino , Voluntários Saudáveis , Humanos , Masculino , Movimento/fisiologia , Exame Neurológico , Valores de Referência
8.
Musculoskelet Sci Pract ; 50: 102258, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32966955

RESUMO

BACKGROUND: Neurodynamic tests (NDTs) consist of a combination of movements aimed to stress different parts of the nervous system and are considered to be able to detect increased nerve mechanosensitivity. Currently, there are no studies in healthy subjects that define the normal response to sural neurodynamic test (NDTSUR). OBJECTIVES: The main aim of this study was to document normal responses of the NDTSUR in asymptomatic participants. The secondary aim was to investigate potential gender and leg dominance influences. DESIGN: A cross-sectional study was designed. METHODS: NDTSUR was performed on 44 asymptomatic participants with a total of 88 lower limbs. The range of motion at the point of first appearance of symptoms (S1) and the point of pain tolerance (S2), quality and distribution of sensory responses were recorded. RESULTS: Hip flexion was significantly greater (p < 0.001) at S2 (63.6 ± 13.1°) than S1 (42.5 ± 12°) and the mean difference was 21.8° (95% CI: 21.8; 22.8) (p < 0.001). However, hip flexion was not different between gender nor dominance (p > 0.05). The descriptor of the quality of the sensory responses more often used by participants was stretching (87% and 76% for S1 and S2, respectively) in the posterior knee and lateral leg. CONCLUSIONS: This study describes the sensory responses of asymptomatic participants resulting from the NDTSUR. The findings indicate that NDTSUR responses are independent of the influence of gender or leg dominance.


Assuntos
Movimento , Estudos Transversais , Humanos , Exame Neurológico , Amplitude de Movimento Articular , Valores de Referência
9.
Musculoskelet Sci Pract ; 43: 117-121, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31272895

RESUMO

BACKGROUND: Neurodynamic tests (NDTs) have shown to be useful in evaluating neural tissue involvement. Peroneal nerve reaches high importance in ankle injuries. However, up to date, no study has documented the normal responses for this nerve. OBJECTIVES: The objective of this study was to document normal responses of the peroneal neurodynamic test (NDTPER) in asymptomatic subjects. Differences in sensory response depending on sex and leg dominance were also examined. DESIGN: A cross-sectional study was designed. METHOD: Forty-four asymptomatic subjects with a total of 88 lower limbs were tested. The range of motion (ROM) at the point of first appearance of symptoms (S1) and the point of symptoms tolerance (S2), quality and distribution of sensory responses were recorded. RESULTS: Hip flexion was significantly higher at S2 than S1 (mean difference, 27.22°; 95% CI: 25.29°, 29.14°; p < 0.001). However, it was not different between sex, nor dominance (p > 0.05). The descriptor of the quality of sensory responses more often used by subjects was stretching (90.9%) in the external foot (74.6%). CONCLUSIONS: This study provides the normal hip flexion angle and quality and distribution of sensory responses to the NDTPER in asymptomatic subjects. Responses were independent of the influence of sex or leg dominance.


Assuntos
Exame Neurológico/métodos , Nervo Fibular/fisiologia , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Amplitude de Movimento Articular , Valores de Referência , Reprodutibilidade dos Testes
10.
Enferm. nefrol ; 18(1): 19-22, ene.-mar. 2015. tab
Artigo em Espanhol | IBECS | ID: ibc-134825

RESUMO

Uno de los principales determinantes de la supervivencia de los pacientes en hemodiálisis es la dosis de la misma, las fórmulas comúnmente utilizadas son aquellas basadas en el modelo cinético de la urea. Sin embargo, debido a la necesidad de al menos dos muestras sanguíneas, su aplicabilidad a todas las sesiones de diálisis es bastante escasa. Actualmente casi todos los monitores de diálisis están provistos de sensores de dialisancia iónica, lo que nos permite obtener de forma indirecta y en tiempo real, información acerca del aclaramiento de urea en todas las sesiones de diálisis y sin necesidad de obtener muestras sanguíneas. Con el objetivo de evaluar la correlación que existe entre la dosis de diálisis medida por dialisancia iónica y aquella medida por cinética de Urea mediante la ecuación de KT/V monocompartimental de segunda generación según Daugirdas, diseñamos un estudio transversal que incluye 28 pacientes prevalentes de nuestra unidad de diálisis, obtuvimos datos de dosis de diálisis (aclaramiento, KT, KT/V) por dialisancia iónica y el KT/V según fórmula de Daugirdas de segunda generación. La media de KT/V por dialisancia iónica fue de 1.79 ± 0.29 del KT/V según Daugirdas de 1.95 ± 0.35. En el análisis estadístico encontramos una importante correlación entre ambos métodos (R2 = 0.86 p< 0.001). Con los resultados de este estudio concluimos que la dialisancia iónica es una técnica útil para valorar la dosis de diálisis en nuestros pacientes y su uso debería generalizarse en las distintas unidades de diálisis (AU)


One of the main determinants of survival in patients undergoing chronic hemodialysis is the dialysis dose, the formulas commonly used are those based on the kinetic model of the urea, however due to the need for at least two blood samples, its applicability at all dialysis sessions is quite low. Currently almost all dialysis monitors are equipped with ionic dialysance sensors, allowing to indirectly and at real-time to get information about urea clearance in all dialysis sessions without obtaining blood samples. In order to evaluate the correlation between dialysis dose measured by ionic dialysance and those measured by urea kinetic equation by Kt/V second generation according to Daugirdas, we designed a crosssectional study involving 28 prevalent patients in our dialysis unit, we obtained affiliation data, dialysis dose (clearance, KT, KT/V) by ionic dialysance and KT/V by Daugirdas formula. Average KT/V by ionic dialysance was 0.29 ± 1.79 KT/ V and 0.35 ± 1.95 Daugirdas. The statistical analysis showed a significant correlation between both methods (R2 = 0.86 p <0.001). With the results of this study we conclude that ionic dialysance is a useful tool to assess the dose of dialysis in our patients and it use should be generalized in all dialysis units is showed up by unwillingness among hypertensive patients refractory, rather than an information problem. For this reason, a nursing intervention focused on solving the problem, is necessary (AU)


Assuntos
Humanos , Diálise Renal/métodos , Soluções para Diálise/administração & dosagem , Insuficiência Renal Crônica/terapia , Íons/uso terapêutico , Ureia/urina , Unidades Hospitalares de Hemodiálise
11.
J Eval Clin Pract ; 21(2): 198-201, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25363689

RESUMO

RATIONALE, AIMS AND OBJECTIVES: The debate about whether to dedicate funds to rare diseases (RD) may hinge on the existence of a societal preference for prioritizing rarity. There are scarce studies about the interest of doctors and general society in RD. METHOD: Four groups of future health and non-health professionals were surveyed in a region of Spain to evaluate their opinion on RD. Questions of the study were organized into four groups: general knowledge on RD, prioritization of research of RD, willingness to assign resources to RD and real distribution of resources to RD. RESULTS: A total of 234 students were surveyed. The mean age of the whole study population was 24.0 years and the 83.3% were female. Only around 25% of the survey sample knew the definitions of RD and orphan drugs. Questions related to willingness to assign resources to RD did not reveal statistically significant differences between study groups. Seventy-three per cent considered that the majority of the budget should be used to treat common diseases. However, resident doctors recognized that they have neither experience nor time to diagnose and treat RD. CONCLUSION: Although resident doctors have a little more general knowledge on RD than other surveyed groups, health and non-health future professionals have a low general knowledge on this topic and none of them prioritized the assignment of funds to RD.


Assuntos
Conhecimento , Doenças Raras/economia , Doenças Raras/psicologia , Estudantes/psicologia , Pesquisa Biomédica/economia , Feminino , Alocação de Recursos para a Atenção à Saúde/economia , Pessoal de Saúde , Prioridades em Saúde/economia , Acessibilidade aos Serviços de Saúde , Humanos , Masculino , Produção de Droga sem Interesse Comercial/economia , Espanha , Adulto Jovem
15.
Rev. neurol. (Ed. impr.) ; 50(supl.2): s55-s58, 8 feb., 2010.
Artigo em Espanhol | IBECS | ID: ibc-86864

RESUMO

Introducción. El estreñimiento y la atonía gástrica son dos de los síntomas no motores de la enfermedad más importantes, el primero por su alta prevalencia y precocidad, ya que puede preceder a los síntomas motores en varios años, y el segundo, por las implicaciones en la absorción de medicación oral utilizada en esta enfermedad. Desarrollo. Se revisan los síntomas y su posible tratamiento. Conclusiones. El tratamiento en ambos casos se basa en medidas higienicodietéticas evitando sustancias que disminuyan el peristaltismo, fármacos procinéticos como domperidona y, en ocasiones, infiltración de toxina botulínica, estimulación eléctrica o incluso tratamiento quirúrgico (AU)


Introduction. Constipation and gastric atony are two of the most important non-motor symptoms of the disease. The first is made significant by its high prevalence and precocity, since it may appear several years before the motor symptoms, and the second because of the repercussions it has on the absorption of oral medication used in this disease. Development. Both the symptoms and their possible treatment are reviewed. Conclusions. In both cases treatment is based on hygienic-dietary measures that avoid substances that reduce peristalsis, prokinetic drugs like domperidone and, sometimes, infiltration of botulinum toxin, electrical stimulation or even surgical treatment (AU)


Assuntos
Humanos , Doença de Parkinson/complicações , Doenças do Sistema Digestório/epidemiologia , Síndromes de Malabsorção/epidemiologia , Constipação Intestinal/epidemiologia , Motilidade Gastrointestinal/fisiologia , Levodopa/farmacocinética
16.
Hypertension ; 53(6): 1000-7, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19398659

RESUMO

Recent studies have shown that the epithelial sodium channel (ENaC) is expressed in vascular tissue. However, the role that ENaC may play in the responses to vasoconstrictors and NO production has yet to be addressed. In this study, the contractile responses of perfused pressurized small-diameter rat mesenteric arteries to phenylephrine and serotonin were reduced by ENaC blockade with amiloride (75.1+/-3.2% and 16.9+/-2.3% of control values, respectively; P<0.01) that was dose dependent (EC(50)=88.9+/-1.6 nmol/L). Incubation with benzamil, another ENaC blocker, had similar effects. alpha, beta, and gamma ENaC were identified in small-diameter rat mesenteric arteries using RT-PCR and Western blot with specific antibodies. In situ hybridization and immunohistochemistry localized ENaC expression to the tunica media and endothelium of small-diameter rat mesenteric arteries. Patch-clamp experiments demonstrated that primary cultures of mesenteric artery endothelial cells expressed amiloride-sensitive sodium currents. Mechanical ablation of the endothelium or inhibition of eNOS with N(omega)-nitro-L-arginine inhibited the reduction in contractility caused by ENaC blockers. ENaC inhibitors increased eNOS phosphorylation (Ser 1177) and Akt phosphorylation (Ser 473). The presence of the phosphoinositide 3-kinase inhibitor LY294002 blunted Akt phosphorylation and eNOS phosphorylation and the decrease in the response to phenylephrine caused by blockers of ENaC, indicating that the phosphoinositide 3-kinase/Akt pathway was activated after ENaC inhibition. Finally, we observed that the effects of blockers of ENaC were flow dependent and that the vasodilatory response to shear stress was enhanced by ENaC blockade. Our results identify a previously unappreciated role for ENaC as a negative modulator of eNOS and NO production in resistance arteries.


Assuntos
Endotélio Vascular/fisiologia , Canais Epiteliais de Sódio/metabolismo , Artérias Mesentéricas/fisiologia , Óxido Nítrico Sintase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Amilorida/análogos & derivados , Amilorida/farmacologia , Análise de Variância , Animais , Velocidade do Fluxo Sanguíneo , Western Blotting , Endotélio Vascular/efeitos dos fármacos , Canais Epiteliais de Sódio/efeitos dos fármacos , Imuno-Histoquímica , Hibridização In Situ , Masculino , Artérias Mesentéricas/efeitos dos fármacos , Modelos Animais , Óxido Nítrico/metabolismo , Fosforilação , Probabilidade , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
17.
Endocrine ; 29(2): 299-307, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16785605

RESUMO

Reduction in corticosterone by acute adrenalectomy (5 d) promotes apoptosis in dentate gyrus (DG) granular neurons, an effect concomitant with variations in the expression of the Bcl-2 gene family implicated in apoptotic regulation. However, no studies exist correlating the effect of long-term adrenalectomy (30 d) on the hippocampus in terms of extent of apoptosis and the levels of proteins related to an apoptotic cascade. After 5 d of adrenalectomy, we found an increase in apoptosis of the DG granular region, correlated with an increase in the processing of caspase-9. The magnitude of apoptosis 30 d after adrenalectomy was reduced in the DG granular layer compared with 5 d after adrenalectomy, in close relation to a reduction in the level of processed caspase-9. To understand how the increase in cell survival long after adrenalectomy occurs, we analyzed changes in the expression of genes and proteins related to apoptosis. Long-term adrenalectomy did not change hippocampal pro-apoptotic Bax or antiapoptotic Bcl-2 mRNA levels or protein content with respect to control. However, we found an increase in mRNA levels of the GD's Bcl-x gene, in parallel with the increase in anti-apoptotic BCL-XL protein levels. These results suggest the reduction in apoptosis observed after long-term adrenalectomy occurs through mechanisms that repress proapoptotic genes previously found to be increased at shorter times of adrenalectomy.


Assuntos
Adrenalectomia/efeitos adversos , Apoptose , Hipocampo/citologia , Proteínas Proto-Oncogênicas c-bcl-2/fisiologia , Animais , Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Caspase 9 , Caspases/metabolismo , Sobrevivência Celular , Hipocampo/fisiologia , Masculino , Modelos Biológicos , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
18.
BMC Neurosci ; 7: 40, 2006 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-16712723

RESUMO

BACKGROUND: Corticosterone reduction produced by adrenalectomy (ADX) induces apoptosis in dentate gyrus (DG) of the hippocampus, an effect related to an increase in the expression of the pro-apoptotic gene bax. However it has been reported that there is also an increase of the anti-apoptotic gene bcl-2, suggesting the promotion of a neuroprotective phenomenon, perhaps related to the expression of transforming growth factor beta1 (TGF-beta1). Thus, we have investigated whether TGF-beta1 levels are induced by ADX, and whether apoptosis is increased by blocking the expression of TGF-beta1 with an antisense oligonucleotide (ASO) administered intracerebrally in corticosterone depleted rats. RESULTS: It was observed an increase of apoptosis in DG, 2 and 5 days after ADX, in agreement with a reduction of corticosterone levels. However, the effect of ADX on the number of apoptotic positive cells in DG was decreased 5 days after the lesion. In CA1-CA3 regions, the effect was only observed 2 days after ADX. TGF-beta1 mRNA levels were increased 2 days after ADX. The sustained intracerebro-ventricular administration of a TGF-beta1 ASO via an osmotic mini pump increased apoptosis levels in CA and DG regions 5 days after ADX as well as sham-operated control animals. No significant effect was observed following a scrambled-oligodeoxynucleotide treatment. CONCLUSION: The changes in both the pattern and the magnitude of apoptotic-cell morphology observed 2 and 5 days after ADX suggest that, as a consequence of the reduction of corticosteroids, some trophic mechanisms restricting cell death to a particular time window are elicited. Sustained intracerebral administration of TGF-beta1 ASO increased the apoptosis promoted by ADX, suggesting that TGF-beta1 plays an anti-apoptotic role in vivo in hippocampus.


Assuntos
Apoptose , Corticosterona/sangue , Hipocampo/metabolismo , Oligodesoxirribonucleotídeos Antissenso/farmacologia , Fator de Crescimento Transformador beta/antagonistas & inibidores , Adrenalectomia , Animais , Ventrículos Cerebrais , Expressão Gênica , Hipocampo/citologia , Hipocampo/efeitos dos fármacos , Masculino , Oligodesoxirribonucleotídeos Antissenso/administração & dosagem , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Fator de Crescimento Transformador beta/biossíntese , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta1
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