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1.
Brain Stimul ; 15(1): 63-72, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34767967

RESUMO

BACKGROUND: The efficacy of repetitive transcranial magnetic stimulation (rTMS) for depression may vary depending on the subregion stimulated within the dorsolateral prefrontal cortex (DLPFC). Clinical TMS typically uses scalp-based landmarks for DLPFC targeting, rather than individualized MRI guidance. OBJECTIVE: In rTMS patients, determine the brain systems targeted by multiple DLPFC stimulation rules by computing several surrogate measures: underlying brain targets labeled with connectivity-based atlases, subgenual cingulate anticorrelation strength, and functionally connected networks. METHODS: Forty-nine patients in a randomized controlled trial of rTMS therapy for treatment resistant major depression underwent structural and functional MRI. DLPFC rules were applied virtually using MR-image guidance. Underlying cortical regions were labeled, and connectivity with the subgenual cingulate and whole-brain computed. RESULTS: Scalp-targeting rules applied post hoc to these MRIs that adjusted for head size, including Beam F3, were comparably precise, successful in directly targeting classical DLPFC and frontal networks, and anticorrelated with the subgenual cingulate. In contrast, all rules involving fixed distances introduced variability in regions and networks targeted. The 5 cm rule targeted a transitional DLPFC region with a different connectivity profile from the adjusted rules. Seed-based connectivity analyses identified multiple regions, such as posterior cingulate and inferior parietal lobe, that warrant further study in order to understand their potential contribution to clinical response. CONCLUSION: EEG-based rules consistently targeted DLPFC brain regions with resting-state fMRI features known to be associated with depression response. These results provide a bridge from lab to clinic by enabling clinicians to relate scalp-targeting rules to functionally connected brain systems.


Assuntos
Transtorno Depressivo Resistente a Tratamento , Estimulação Magnética Transcraniana , Depressão/diagnóstico por imagem , Depressão/terapia , Transtorno Depressivo Resistente a Tratamento/diagnóstico por imagem , Transtorno Depressivo Resistente a Tratamento/terapia , Humanos , Imageamento por Ressonância Magnética , Córtex Pré-Frontal/fisiologia , Estimulação Magnética Transcraniana/métodos
2.
Oxid Med Cell Longev ; 2021: 6689403, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34630850

RESUMO

Xeroderma pigmentosum (XP) is a rare autosomal genodermatosis that manifests clinically with pronounced sensitivity to ultraviolet (UV) radiation and the high probability of the occurrence of different skin cancer types in XP patients. XP is mainly caused by mutations in XP-genes that are involved in the nucleotide excision repair (NER) pathway that functions in the removal of bulky DNA adducts. Besides, the aggregation of DNA lesions is a life-threatening event that might be a key for developing various mutations facilitating cancer appearance. One of the key players of NER is XPC that senses helical distortions found in damaged DNA. The majority of XPC gene mutations are nonsense, and some are missense leading either to the loss of XPC protein or to the expression of a truncated nonfunctional version. Given that no cure is yet available, XPC patients should be completely protected and isolated from all types of UV radiations (UVR). Although it is still poorly understood, the characterization of the proteomic signature of an XPC mutant is essential to identify mediators that could be targeted to prevent cancer development in XPC patients. Unraveling this proteomic signature is fundamental to decipher the signaling pathways affected by the loss of XPC expression following exposure to UVB radiation. In this review, we will focus on the signaling pathways disrupted in skin cancer, pathways modulating NER's function, including XPC, to disclose signaling pathways associated with XPC loss and skin cancer occurrence.


Assuntos
Reparo do DNA/genética , Transdução de Sinais/genética , Neoplasias Cutâneas/metabolismo , Xeroderma Pigmentoso/genética , Xeroderma Pigmentoso/metabolismo , Animais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Códon sem Sentido/efeitos da radiação , Dano ao DNA/efeitos da radiação , Reparo do DNA/efeitos da radiação , Humanos , Incidência , Proteoma , Proteômica/métodos , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/genética , Raios Ultravioleta/efeitos adversos , Xeroderma Pigmentoso/complicações
3.
Brain Stimul ; 14(3): 703-709, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33866020

RESUMO

BACKGROUND: Precise targeting of brain functional networks is believed critical for treatment efficacy of rTMS (repetitive pulse transcranial magnetic stimulation) in treatment resistant major depression. OBJECTIVE: To use imaging data from a "failed" clinical trial of rTMS in Veterans to test whether treatment response was associated with rTMS coil location in active but not sham stimulation, and compare fMRI functional connectivity between those stimulation locations. METHODS: An imaging substudy of 49 Veterans (mean age, 56 years; range, 27-78 years; 39 male) from a randomized, sham-controlled, double-blinded clinical trial of rTMS treatment, grouping participants by clinical response, followed by group comparisons of treatment locations identified by individualized fiducial markers on structural MRI and resting state fMRI derived networks. RESULTS: The average stimulation location for responders versus nonresponders differed in the active but not in the sham condition (P = .02). The average responder location derived from the active condition showed significant negative functional connectivity with the subgenual cingulate (P < .001) while the nonresponder location did not (P = .17), a finding replicated in independent cohorts of 84 depressed and 35 neurotypical participants. The responder and nonresponder stimulation locations evoked different seed based networks (FDR corrected clusters, all P < .03), revealing additional brain regions related to rTMS treatment outcome. CONCLUSION: These results provide evidence from a randomized controlled trial that clinical response to rTMS is related to accuracy in targeting the region within DLPFC that is negatively correlated with subgenual cingulate. These results support the validity of a neuro-functionally informed rTMS therapy target in Veterans.


Assuntos
Transtorno Depressivo Resistente a Tratamento , Estimulação Magnética Transcraniana , Encéfalo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Córtex Pré-Frontal , Resultado do Tratamento
4.
Oxid Med Cell Longev ; 2019: 4654206, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31485292

RESUMO

The continuous exposure of the human body's cells to radiation and genotoxic stresses leads to the accumulation of DNA lesions. Fortunately, our body has several effective repair mechanisms, among which is nucleotide excision repair (NER), to counteract these lesions. NER includes both global genome repair (GG-NER) and transcription-coupled repair (TC-NER). Deficiencies in the NER pathway underlie the development of several DNA repair diseases, such as xeroderma pigmentosum (XP), Cockayne syndrome (CS), and trichothiodystrophy (TTD). Deficiencies in GG-NER and TC-NER render individuals to become prone to cancer and neurological disorders, respectively. Therefore, NER regulation is of interest in fine-tuning these risks. Distinct signaling cascades including the NFE2L2 (NRF2), AHR, PI3K/AKT1, MAPK, and CSNK2A1 pathways can modulate NER function. In addition, several chemical and biological compounds have proven success in regulating NER's activity. These modulators, particularly the positive ones, could therefore provide potential treatments for genetic DNA repair-based diseases. Negative modulators, nonetheless, can help sensitize cells to killing by genotoxic chemicals. In this review, we will summarize and discuss the major upstream signaling pathways and molecules that could modulate the NER's activity.


Assuntos
Síndrome de Cockayne/metabolismo , Dano ao DNA , Reparo do DNA , Transdução de Sinais , Síndromes de Tricotiodistrofia/metabolismo , Raios Ultravioleta/efeitos adversos , Xeroderma Pigmentoso/metabolismo , Animais , Síndrome de Cockayne/patologia , Humanos , Síndromes de Tricotiodistrofia/patologia , Xeroderma Pigmentoso/patologia
5.
Br J Cancer ; 113(1): 91-8, 2015 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-26068396

RESUMO

BACKGROUND: We previously demonstrated an inverse correlation between tyrosinase-related protein 1 (TYRP1) mRNA expression in melanoma metastases and patient survival. However, TYRP1 protein was not detected in half of tissues expressing mRNA and did not correlate with survival. Based on a study reporting that 3' untranslated region (UTR) of TYRP1 mRNA contains two miR-155-5p (named miR-155) binding sites exhibiting single-nucleotide polymorphisms (SNPs) that promote (matched miRNA-mRNA interaction) mRNA decay or not (mismatched), we aimed to investigate the role of miR-155 in the regulation of TYRP1 mRNA expression and protein translation accounting for these SNPs. METHODS: The effect of miR-155 on TYRP1 mRNA/protein expression was evaluated in two melanoma cell lines harbouring matched or mismatched miR-155-TYRP1 mRNA interaction after transfection with pre-miR-155. In parallel, 192 skin and lymph node melanoma metastases were examined for TYRP1 mRNA/protein, miR-155 and SNPs and correlated with patient survival. TYRP1 mRNA, SNPs at its 3'UTR and miR-155 were analysed by RT-qPCR, whereas TYRP1 protein was evaluated by western blot in cell lines and by immunohistochemistry in metastatic tissues. RESULTS: The miR-155 induced a dose-dependent TYRP1 mRNA decay and hampered its translation into protein in the line with the 'match' genotype. In melanoma metastases, TYRP1 mRNA inversely correlated with miR-155 expression but not with TYRP1 protein in the 'match' group, whereas it positively correlated with protein but not with miR-155 in the 'mismatch' group. Consequently, in the latter group, TYRP1 protein inversely correlated with survival. CONCLUSION: Polymorphisms in 3'UTR of TYRP1 mRNA can affect TYRP1 mRNA regulation by miR-155 and its subsequent translation into protein. These SNPs can render TYRP1 mRNA and protein expression nonsusceptible to miR-155 activity and disclose a prognostic value for TYRP1 protein in a subgroup of melanoma patients. These data support the interest in the prognostic value of melanogenic markers and propose TYRP1 to refine prognosis in patients with advanced disease.


Assuntos
Melanoma/patologia , Glicoproteínas de Membrana/metabolismo , MicroRNAs/genética , Oxirredutases/metabolismo , Polimorfismo de Nucleotídeo Único , RNA Mensageiro/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Sequência de Bases , Linhagem Celular Tumoral , Primers do DNA , Feminino , Genótipo , Humanos , Masculino , Melanoma/genética , Melanoma/metabolismo , Glicoproteínas de Membrana/genética , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Oxirredutases/genética , Reação em Cadeia da Polimerase , Prognóstico , Adulto Jovem
6.
Int J Oral Maxillofac Surg ; 44(8): 1048-51, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25979192

RESUMO

Burning mouth syndrome (BMS) is a persistent and chronic burning sensation in the mouth in the absence of any abnormal organic findings. The pathophysiology of BMS is unclear and its treatment is not fully established. Although antidepressant medication is commonly used for treatment, there are some medication-resistant patients, and a new treatment for medication-resistant BMS is needed. Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive brain stimulation technology approved by the US Food and Drug Administration (FDA) for the treatment of depression. Recent studies have found beneficial effects of TMS for the treatment of pain. A case of BMS treated successfully with daily left prefrontal rTMS over a 2-week period is reported here. Based on this patient's clinical course and a recent pain study, the mechanism by which TMS may act to decrease the burning pain is discussed.


Assuntos
Síndrome da Ardência Bucal/terapia , Estimulação Magnética Transcraniana/métodos , Síndrome da Ardência Bucal/fisiopatologia , Feminino , Humanos , Pessoa de Meia-Idade , Medição da Dor , Resultado do Tratamento
7.
Int J Obstet Anesth ; 23(4): 317-23, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25281437

RESUMO

BACKGROUND: Hypotension is a common problem during spinal anesthesia for cesarean delivery. Intravenous fluid loading is used to correct preoperative dehydration and reduce the incidence and severity of hypotension. Different fluid regimens have been studied but colloid preload and crystalloid co-load have not been compared. METHODS: In this randomized double-blind study, 210 patients scheduled for elective cesarean section under spinal anesthesia were randomly allocated to receive either 6% hydroxyethyl starch 130/0.4 500 mL before spinal anesthesia (colloid preload) or Ringer's acetate solution 1000 mL administered rapidly starting with intrathecal injection (crystalloid co-load). Maternal hypotension (systolic blood pressure <80% of baseline or <90 mmHg) and severe hypotension (systolic blood pressure <80 mmHg) were treated with 5 and 10mg ephedrine boluses, respectively. The primary outcome was the incidence of hypotension. Secondary outcomes included the incidence of severe hypotension, total ephedrine dose, nausea and vomiting and neonatal outcome assessed by Apgar scores and umbilical artery blood gas analysis. RESULTS: Data analysis was performed on 205 patients; 103 in the colloid preload group and 102 in the crystalloid co-load group. There were no significant differences in the incidence of hypotension (52.4% vs. 42.2%; P=0.18) or severe hypotension (15.5% vs. 9.8%; P=0.31) between colloid preload and crystalloid co-load groups, respectively. The median [range] ephedrine dose was 5 [0-45]mg in the colloid preload group and 0 [0-35]mg in the crystalloid co-load group (P=0.065). There were no significant differences in maternal nausea or vomiting or neonatal outcomes between groups. CONCLUSION: The use of 1000 mL crystalloid co-load has similar effect to 500 mL colloid preload in reducing the incidence of hypotension after spinal anesthesia for elective cesarean delivery. Neither technique can totally prevent hypotension and should be combined with vasopressor use.


Assuntos
Anestesia Obstétrica/métodos , Raquianestesia/métodos , Cesárea/métodos , Coloides/uso terapêutico , Soluções Isotônicas/uso terapêutico , Substitutos do Plasma/uso terapêutico , Adulto , Índice de Apgar , Gasometria , Pressão Sanguínea/efeitos dos fármacos , Coloides/efeitos adversos , Soluções Cristaloides , Método Duplo-Cego , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Soluções Isotônicas/efeitos adversos , Substitutos do Plasma/efeitos adversos , Medicação Pré-Anestésica , Gravidez , Resultado da Gravidez , Resultado do Tratamento , Adulto Jovem
8.
Br J Cancer ; 108(8): 1641-7, 2013 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-23519055

RESUMO

BACKGROUND: Clinical outcome of high-risk melanoma patients is not reliably predicted from histopathological analyses of primary tumours and is often adjusted during disease progression. Our study aimed at extending our previous findings in skin metastases to evaluate the prognostic value of tyrosinase-related protein 1 (TYRP1) in lymph node metastases of stages III and IV melanoma patients. METHODS: TYRP1 mRNA expression in 104 lymph node metastases was quantified by real-time PCR and normalised to S100 calcium-binding protein B (S100B) mRNA expression to correct for tumour load. TYRP1/S100B ratios were calculated and median was used as cutoff value. TYRP1/S100B mRNA values were correlated to clinical follow-up and histopathological characteristics of the primary lesion. RESULTS: A high TYRP1/S100B mRNA ratio significantly correlated with reduced disease-free (DFS) and overall survival (OS; Cox regression analysis, P=0.005 and 0.01, respectively), increased Breslow thickness (Spearman's rho test, P<0.001) and the presence of ulceration (Mann-Whitney test, P=0.02) of the primaries. Moreover, high TYRP1/S100B was of better prognostic value (lower P-value) for OS than Breslow thickness and ulceration. Finally, it was well conserved during disease progression with respect to high/low TYRP1 groups. CONCLUSION: High TYRP1/S100B mRNA expression in lymph node metastases from melanoma patients is associated with unfavourable clinical outcome. Its evaluation in lymph node metastases may refine initial prognosis for metastatic patients, may define prognosis for those with unknown or non-evaluable primary lesions and may allow different management of the two groups of patients.


Assuntos
Linfonodos/metabolismo , Melanoma/genética , Glicoproteínas de Membrana/genética , Oxirredutases/genética , RNA Mensageiro/biossíntese , Adolescente , Adulto , Idoso , Biomarcadores Tumorais/biossíntese , Biomarcadores Tumorais/genética , Intervalo Livre de Doença , Feminino , Humanos , Linfonodos/patologia , Metástase Linfática , Masculino , Melanoma/enzimologia , Melanoma/patologia , Glicoproteínas de Membrana/biossíntese , Pessoa de Meia-Idade , Fatores de Crescimento Neural/biossíntese , Fatores de Crescimento Neural/genética , Oxirredutases/biossíntese , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Risco , Subunidade beta da Proteína Ligante de Cálcio S100 , Proteínas S100/biossíntese , Proteínas S100/genética , Taxa de Sobrevida , Adulto Jovem
9.
J Contemp Dent Pract ; 14(6): 1122-30, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-24858762

RESUMO

AIM: Microleakage quantification of fluids and microorganisms through the connections of different implant parts seems to be sparse. Moreover, no data exist regarding the determination of the volumes of inner parts of dental implant systems. This study aims to determine the volumes of inner parts of three dental implant systems with the same interface and to evaluate the microleakage phenomenon. MATERIALS AND METHODS: Three implant system sets (Euro-teknika(®), Astra Tech(®) and Implantium(®)) were used in this study. Implants were inoculated with safranin, brain heart infusion and distilled water. After inoculation and assembly of the different parts, different inner volumes (V1, V2, V3, V4, V5 and V6) were measured and, the surfaces of the micro gaps were observed through a stereomicroscope. Implants containing safranin were immersed in vials containing distilled water. Samples then were taken to determine optical density using a spectrophotometer. RESULTS: Regardless the used substance, volumes of the 3-implant systems are different. Although volumes V1, V 2, V 3 and V5 appeared to be constant within the same system regardless the used substance, volumes V4 and V6 were not. CONCLUSION: The determination of the volumes and the evaluation of leaked substance using stereomicroscopic and spectrophotometric methods showed the accuracy of these methods and the importance of their use in the study of microleakage. CLINICAL SIGNIFICANCE: Leakage is an important factor for chronic inflammatory infiltration and marginal bone resorption. Studies have shown fluid and bacterial leakage into abutment- implant (A-I) assemblies of certain implants with 'closely locked' abutments and the creation of a constant bacterial reservoir in the empty space found between the implant and the abutment.


Assuntos
Projeto do Implante Dentário-Pivô , Implantes Dentários , Infiltração Dentária/classificação , Planejamento de Prótese Dentária , Corantes , Meios de Cultura , Adaptação Marginal Dentária , Humanos , Teste de Materiais , Microscopia/métodos , Fenazinas , Projetos Piloto , Espectrofotometria/métodos , Torque , Água/química
10.
Leukemia ; 21(4): 788-96, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17287851

RESUMO

Adult T-cell leukemia/lymphoma (ATLL) is a malignancy slowly emerging from human T-cell leukemia virus type 1 (HTLV-I)-infected mature CD4(+) T-cells. To characterize the molecular modifications induced by HTLV-I infection, we compared HTLV-I-infected WE17/10 cells with control cells, using micro-arrays. Many calcium-related genes were progressively downmodulated over a period of 2 years. Infected cells acquired a profound decrease of intracellular calcium levels in response to ionomycin, timely correlated with decreased CD7 expression. Focusing on apoptosis-related genes and their relationship with CD7, we observed an underexpression of most antiapoptotic genes. Western blotting revealed increasing Akt and Bad phosphorylation, timely correlated with CD7 loss. This was shown to be phosphatidylinositol 3-kinase (PI3K)-dependent. Activation of PI3K/Akt induced resistance to the apoptotic effect of interleukin-2 deprivation. We thus propose the following model: HTLV-I infection induces a progressive decrease in CD3 genes expression, which eventually abrogates CD3 expression; loss of CD3 is known to perturb calcium transport. This perturbation correlates with loss of CD7 expression and induction of Akt and Bad phosphorylation via activation of PI3K. The activation of the Akt/Bad pathway generates a progressive resistance to apoptosis, at a time HTLV-I genes expression is silenced, thus avoiding immune surveillance. This could be a major event in the process of the malignant transformation into ATLL.


Assuntos
Antígenos CD7/genética , Linfócitos T CD4-Positivos/imunologia , Sinalização do Cálcio/fisiologia , Transformação Celular Neoplásica , Infecções por HTLV-I/fisiopatologia , Proteína Oncogênica v-akt/genética , Proteína de Morte Celular Associada a bcl/genética , Antígenos CD7/fisiologia , Apoptose , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/patologia , Linhagem Celular , Citometria de Fluxo , Regulação Viral da Expressão Gênica , Humanos , Ionomicina/farmacologia , Proteína Oncogênica v-akt/fisiologia , RNA/genética , RNA/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteína de Morte Celular Associada a bcl/fisiologia
11.
Popul Bull ESCWA ; (40): 69-92, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-12287049

RESUMO

"This study reviews the demographic situation in Jordan from both Arab and international perspectives and provides an introduction to the nature and characteristics of Jordanian demographic policy and [implementation]. The study seeks to highlight government and private efforts pertaining to family planning. [It reviews] the more important demographic changes in Jordan in addition to providing official and international statistics for the second half of the 1980s."


Assuntos
Serviços de Planejamento Familiar , Dinâmica Populacional , Política Pública , Ásia , Ásia Ocidental , Demografia , Países em Desenvolvimento , Jordânia , Oriente Médio , População
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