Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 57
Filtrar
1.
Nat Commun ; 14(1): 6646, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37863907

RESUMO

Geometrically frustrated kagome lattices are raising as novel platforms to engineer correlated topological electron flat bands that are prominent to electronic instabilities. Here, we demonstrate a phonon softening at the kz = π plane in ScV6Sn6. The low energy longitudinal phonon collapses at ~98 K and q = [Formula: see text] due to the electron-phonon interaction, without the emergence of long-range charge order which sets in at a different propagation vector qCDW = [Formula: see text]. Theoretical calculations corroborate the experimental finding to indicate that the leading instability is located at [Formula: see text] of a rather flat mode. We relate the phonon renormalization to the orbital-resolved susceptibility of the trigonal Sn atoms and explain the approximately flat phonon dispersion. Our data report the first example of the collapse of a kagome bosonic mode and promote the 166 compounds of kagomes as primary candidates to explore correlated flat phonon-topological flat electron physics.

2.
ESMO Open ; 7(6): 100641, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36462464

RESUMO

BACKGROUND: Selective tyrosine kinase inhibitors targeting fibroblast growth factor receptor (FGFR) 1-4 genomic alterations are in development or have been approved for FGFR-altered cancers (e.g. bladder cancer and advanced intrahepatic cholangiocarcinoma). Understanding FGFR inhibitor-resistance mechanisms is increasingly relevant; we surveyed the pan-tumor landscape of FGFR1-4 genomic alterations [short variants (SVs), gene rearrangements (REs), and copy number alterations (CNAs)], including their association with tumor mutational burden (TMB) and the genomic comutational landscape. PATIENTS AND METHODS: Comprehensive genomic profiling of 355 813 solid tumor clinical cases was performed using the FoundationOne and FoundationOne CDx assays (Foundation Medicine, Inc.) to identify genomic alterations in >300 cancer-associated genes and TMB (determined on ≤1.1 megabases of sequenced DNA). RESULTS: FGFR1-4 SVs and REs occurred in 9603/355 813 (2.7%), and CNAs in 15 078/355 813 (4.2%) samples. Most common FGFR alterations for bladder cancer, intrahepatic cholangiocarcinoma, and glioma were FGFR3 SVs (1051/7739, 13.6%), FGFR2 REs (618/6641, 9.3%), and FGFR1 SVs (239/11 550, 2.1%), respectively. We found several, potentially clinically relevant, tumor-specific associations between FGFR1-4 genomic alterations and other genomic markers. FGFR3 SV-altered bladder cancers and FGFR1 SV-altered gliomas were significantly less likely to be TMB-high versus unaltered samples. FGFR3 SVs in bladder cancer significantly co-occurred with TERT and CDKN2A/B alterations; TP53 and RB1 alterations were mutually exclusive. In intrahepatic cholangiocarcinoma, FGFR2 REs significantly co-occurred with BAP1 alterations, whereas KRAS, TP53, IDH1, and ARID1A alterations were mutually exclusive. FGFR1 SVs in gliomas significantly co-occurred with H3-3A and PTPN11 alterations, but were mutually exclusive with TERT, EGFR, TP53, and CDKN2A/B alterations. CONCLUSIONS: Overall, our hypothesis-generating findings may help to stratify patients in clinical trials and guide optimal targeted therapy in those with FGFR alterations.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Glioma , Neoplasias da Bexiga Urinária , Humanos , Ductos Biliares Intra-Hepáticos , Biomarcadores Tumorais/genética , Colangiocarcinoma/genética , Genômica , Glioma/genética , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/genética , Receptores Proteína Tirosina Quinases/metabolismo
3.
Acta Crystallogr F Struct Biol Commun ; 75(Pt 5): 359-367, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31045565

RESUMO

As of 2017, tuberculosis had infected 1.7 billion people (23% of the population of the world) and caused ten million deaths. Mycobacterium tuberculosis (Mtb) is quickly evolving, and new strains are classified as multidrug resistant. Thus, the identification of novel druggable targets is essential to combat the proliferation of these drug-resistant strains. Filamenting temperature-sensitive mutant Z (FtsZ) is a key protein involved in cytokinesis, an important process for Mtb proliferation and viability. FtsZ is required for bacterial cell division because it polymerizes into a structure called the Z-ring, which recruits accessory division proteins to the septum. Here, the crystal structure of the MtbFtsZ protein has been determined to 3.46 Šresolution and is described as a dimer of trimers, with an inter-subunit interface between protomers AB and DE. In this work, a novel conformation of MtbFtsZ is revealed involving the T9 loop and the nucleotide-binding pocket of protomers BC and EF.


Assuntos
Proteínas de Bactérias/química , Proteínas do Citoesqueleto/química , Mycobacterium tuberculosis/química , Subunidades Proteicas/química , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Sítios de Ligação , Divisão Celular , Clonagem Molecular , Cristalografia por Raios X , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Cinética , Modelos Moleculares , Mutação , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Multimerização Proteica , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Homologia Estrutural de Proteína , Temperatura
4.
Interv Neuroradiol ; 19(2): 235-9, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23693049

RESUMO

Carotid artery pseudoaneurysm is a rare complication from placement of an internal jugular triple lumen catheter. Endovascular stenting is the favored treatment option in the setting of traumatic carotid injury. In other parts of the body, specifically the femoral artery, thrombin injection has become the standard of care. We intend to show that effective management of carotid pseudoaneurysms can also be achieved with thrombin injection after placement of a distal embolic protection device.


Assuntos
Lesões das Artérias Carótidas/etiologia , Lesões das Artérias Carótidas/cirurgia , Cateterismo Periférico/efeitos adversos , Embolização Terapêutica/instrumentação , Embolização Terapêutica/métodos , Trombólise Mecânica/instrumentação , Trombina/administração & dosagem , Idoso , Lesões das Artérias Carótidas/diagnóstico por imagem , Terapia Combinada , Hemostáticos/administração & dosagem , Humanos , Injeções Subcutâneas , Masculino , Trombólise Mecânica/métodos , Radiografia , Resultado do Tratamento
5.
Interv Neuroradiol ; 19(2): 250-3, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23693052

RESUMO

Multiple treatment options have been introduced for the treatment of sacral tumoral bone pain. These options include pre-operative sacral embolization, percutaneous cryoablation, alcohol ablation, and sacroplasty. We intend to show that in the correct clinical scenario, a combination of the four procedures performed as a two-stage process can effectively treat tumoral bone pain refractory to medical therapy.


Assuntos
Carcinoma de Células Renais/secundário , Carcinoma de Células Renais/terapia , Dor/prevenção & controle , Sacro/cirurgia , Neoplasias da Coluna Vertebral/secundário , Neoplasias da Coluna Vertebral/terapia , Vertebroplastia/métodos , Idoso , Carcinoma de Células Renais/etiologia , Terapia Combinada , Criocirurgia/métodos , Embolização Terapêutica/métodos , Etanol/uso terapêutico , Hemostáticos/uso terapêutico , Humanos , Masculino , Dor/etiologia , Soluções Esclerosantes/uso terapêutico , Neoplasias da Coluna Vertebral/complicações , Resultado do Tratamento
6.
Parasitology ; 138(3): 267-78, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20880419

RESUMO

Giardia lamblia, a protozoan parasite, infects a wide variety of vertebrates, including humans. Studies indicate that this anaerobic protist possesses a limited ability to synthesize lipid molecules de novo and depends on supplies from its environment for growth and differentiation. It has been suggested that most lipids and fatty acids are taken up by endocytic and non-endocytic pathways and are used by Giardia for energy production and membrane/organelle biosynthesis. The purpose of this article is to provide an update on recent progress in the field of lipid research of this parasite and the validation of lipid metabolic pathways through recent genomic information. Based on current cellular, biochemical and genomic data, a comprehensive pathway has been proposed to facilitate our understanding of lipid and fatty acid metabolism/syntheses in this waterborne pathogen. We envision that the current review will be helpful in identifying targets from the pathways that could be used to design novel therapies to control giardiasis and related diseases.


Assuntos
Bases de Dados de Ácidos Nucleicos , Ácidos Graxos/metabolismo , Giardia lamblia/metabolismo , Metabolismo dos Lipídeos/genética , Proteínas de Protozoários/genética , Animais , Genoma/genética , Giardia lamblia/genética , Giardíase/parasitologia , Humanos , Proteínas de Protozoários/metabolismo
7.
J Maxillofac Oral Surg ; 10(2): 170-2, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22654373

RESUMO

Hemimasticatory spasm is a rare neuromuscular disorder where the patient experiences involuntary, painful spasm of muscles of mastication. Only 15 cases have been reported in literature. We present a case which was treated unconventionally with satisfactory outcome.

9.
Int J Gynecol Cancer ; 16(3): 1048-54, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16803484

RESUMO

To understand the role of human papillomavirus (HPV) in recurrence of uterine cervical cancer (CA-CX) after radiotherapy, we have analyzed the HPV prevalence in the exfoliated cells of 56 patients and their corresponding plasma. HPV DNA was detected in exfoliated cells of 78% (44/56) patients (HPV-16, 68%; HPV-18, 14%; HPV-X [other than 16, 18], 11%; and mixed infection of HPV-16 and HPV-18 in three cases). HPV DNA in plasma was present in only 25% (11/44) of the HPV-positive exfoliated cells (positive predictive value, 100%; negative predictive value, 27%) with concordance in HPV types. The recurrence of the disease was significantly associated with the presence of HPV in the exfoliated cell (P= 0.01) and plasma (P= 0.007) as well as high viral load in the exfoliated cell (P= 0.0002). Kaplan-Meier disease-free estimates have also shown the significant association between HPV prevalence in plasma and recurrence of the disease (P= 0.045). Thus, it indicates that in postradiotherapy CA-CX patients, the high viral load in the exfoliated cell as well as HPV presence in the plasma samples could be used in early detection of the patients at increased risk for disease recurrence and progression.


Assuntos
Carcinoma/radioterapia , Carcinoma/virologia , Recidiva Local de Neoplasia/epidemiologia , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/epidemiologia , Neoplasias do Colo do Útero/radioterapia , Neoplasias do Colo do Útero/virologia , Adulto , Assistência ao Convalescente/estatística & dados numéricos , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Infecções por Papillomavirus/sangue , Infecções por Papillomavirus/complicações , Prevalência , Sensibilidade e Especificidade , Análise de Sobrevida , Neoplasias do Colo do Útero/mortalidade , Esfregaço Vaginal , Carga Viral/estatística & dados numéricos
10.
Acta Crystallogr C ; 61(Pt 4): o201-3, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15805624

RESUMO

The title compound, C21H28O4, a synthetic glucocorticoid, crystallizes with a single molecule in the asymmetric unit. Ring A is almost in a half-chair conformation, rings B and C are almost in chair conformations, and ring D is between a twist and a 13beta-envelope conformation. The A/B ring junction is quasi-trans, whereas the B/C and C/D ring junctions both approach trans characteristics. The molecule as a whole is slightly convex towards the beta side, with an angle of 9.60 (2) degrees between the C10-C19 and C13-C18 vectors. Molecular-packing and hydrogen-bonding (both intra- and intermolecular) interactions play a major role in the structural association of the compound.


Assuntos
Cortisona/análogos & derivados , Cortisona/química , Cristalografia por Raios X , Ligação de Hidrogênio , Modelos Moleculares , Conformação Molecular
11.
Gynecol Oncol ; 95(2): 352-62, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15491757

RESUMO

OBJECTIVES: We have been done the detailed deletion mapping of chromosome (chr.) 8p21.3-23 to localize the candidate tumor suppressor gene(s) (TSGs) loci as well as studied the mechanism of activation of c-myc gene, located at chr.8q24.1, by analyzing the amplification/rearrangement/HPV integration within approximately 580 kb of c-myc locus in uterine cervical carcinoma (CaCx) of Indian patients. The association between the deletions in chr.8p21.3-23 and alterations in the c-myc locus has also been analyzed. METHODS: The deletion mapping of chr.8p21.3-23 was done by 15 microsatellite markers and the alterations in the c-myc locus were analyzed by Southern hybridization using the pal-1/c-myc/mlvi-4/HPV 16/18 probes in seven cervical intraepithelial neoplasia (CIN) and 55 primary uterine cervical carcinoma. The alterations in chr.8p/q have been correlated with the different clinicopathological parameters. RESULTS: Three discrete minimal deleted regions with high frequencies of loss of heterozygosity (LOH) (37-43%) were identified in the chr.8p23.1-23.2 (D1), 8p23.1 (D2), and 8p 21.3-22 (D3) regions within 0.41-4.62 Mb. The deletion in the D1 region was significantly associated with the deletion in the D2 region (P = 0.03), whereas the deletion in D2 was marginally associated with the deletion in the D3 region (P = 0.07). The alterations in the c-myc locus were seen in 43% of the samples. About 35% of the samples showed coalterations in both arms of chr.8. No significant association was observed with the alterations in chr.8p/q as well as with the different clinicopathological parameters. CONCLUSIONS: The deletions in chr.8p21.3-23 and the alterations in the c-myc locus are independently associated with the development of CaCx. The D1-D3 regions in chr.8p21.3-23 could harbor candidate TSGs associated with the development of this tumor. The c-myc gene was activated by amplification/rearrangement at the pal-1/c-myc/mlvi-4 loci as well as HPV integration in the pal-1 locus in this tumor.


Assuntos
Aberrações Cromossômicas , Cromossomos Humanos Par 8/genética , Neoplasias do Colo do Útero/genética , Adulto , Idoso , Mapeamento Cromossômico , Feminino , Genes Supressores de Tumor , Genes myc/genética , Predisposição Genética para Doença , Humanos , Índia , Perda de Heterozigosidade , Pessoa de Meia-Idade , Papillomaviridae , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/genética , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/virologia
12.
Exp Mol Pathol ; 76(3): 264-71, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15126110

RESUMO

Deletion in the 22.9 -Mb chromosomal (chr.) 8p21.3-23 region has been shown to be necessary for the development of breast carcinoma (CaBr). In this study, we have attempted to detect the minimal deleted region(s) in the chr.8p21.3-23 region in 62 primary breast lesions having 56 CaBr tumors and six other breast lesions of Indian patients using 15 microsatellite markers. The loss of heterozygosity (LOH) was observed for at least one marker in 96.4% (54/56) of the CaBr samples. Three discrete minimal deleted regions with high frequencies of LOH (39-65%) were identified in the chromosomal 8p23.1-23.2 (D1), 8p23.1 (D2) and 8p 21.3-22 (D3) regions within 2.03, 0.41, 2.47 Mb, respectively. No significant correlation was observed with the high deleted regions and the different clinicopathological parameters. Interestingly, 51.8% (29/56) CaBr samples showed either loss of chr.8p or interstitial deletions in this arm, indicating the importance of chr.8p in the development of CaBr. The pattern of allelic loss in the bilateral lesions had indicated that the lesions were clonal in origin and probably the deletion in the D3 region was the early event among the D1-D3 regions. Thus, our data have indicated that the D1-D3 regions could harbor candidate tumor suppressor gene(s) (TSGs) associated with the development of CaBr.


Assuntos
Neoplasias da Mama/genética , Cromossomos Humanos Par 8/genética , Fibroadenoma/genética , Adulto , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/patologia , DNA de Neoplasias/genética , Feminino , Fibroadenoma/epidemiologia , Fibroadenoma/patologia , Genes Supressores de Tumor , Humanos , Índia/epidemiologia , Perda de Heterozigosidade , Repetições de Microssatélites
13.
Indian J Med Res ; 118: 77-85, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-14680203

RESUMO

BACKGROUND & OBJECTIVES: Deletions in chromosome 8 (chr.8) have been shown to be necessary for the development of head and neck squamous cell carcinoma (HNSCC). Attempts have been made in this study to detect the minimal deleted region in chr.8 associated with the development of HNSCC in Indian patients and to study the association of clinicopathological features with the progression of the disease. METHODS: The deletion mapping of chr.8 was done in samples from 10 primary dysplastic lesions and 43 invasive squamous cell carcinomas from the head and neck region of Indian patients to detect allelic alterations (deletion or size alteration) using 12 highly polymorphic microsatellite markers. The association of the highly deleted region was correlated with the tumour node metastasis (TNM) stages, nodal involvement, tobacco habit and human papilloma virus (HPV) infection of the samples. RESULTS: High frequency (49%) of loss of heterozygosity (LOH) was seen within 13.12 megabase (Mb) region of chromosomal 8p21.3-23 region in the HNSCC samples, whereas the dysplastic samples did not show any allelic alterations in this region. The highest frequency (17%) of microsatellite size alterations (MA) was observed in the chr.8p22 region. The loss of short arm or normal copy of chr.8 and rare bi-allelic alterations were seen in the stage II-IV tumours (939, 5184, 2772, 1319 and 598) irrespective of their primary sites. The highly deleted region did not show any significant association with any of the clinical parameters. However, HPV infection was significantly associated (P < 0.05) with the differentiation grades and overall allelic alterations (LOH/MA) of the samples. INTERPRETATION & CONCLUSION: Our data indicate that the 13.12 Mb deleted region in the chromosomal 8p21.3-23 region could harbour candidate tumour suppressor gene(s) (TSGs) associated with the progression anti invasion of HNSCC tumours in Indian patients.


Assuntos
Carcinoma de Células Escamosas/genética , Deleção Cromossômica , Cromossomos Humanos Par 8 , Neoplasias de Cabeça e Pescoço/genética , Alelos , Sequência de Bases , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/virologia , Primers do DNA , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/virologia , Humanos , Índia , Perda de Heterozigosidade , Masculino , Papillomaviridae/isolamento & purificação
14.
Mol Pathol ; 56(5): 263-9, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14514919

RESUMO

BACKGROUND: Deletions in chromosome 3 occur frequently in uterine cervical carcinoma (CA-CX). The common consensus regions deleted during CA-CX development are not well defined, and have not been correlated with tumour progression. AIMS: To define specific regions of chromosome 3 deleted during development of CA-CX and to correlate these with clinicopathological data. METHODS: Deletion mapping of chromosome 3 was done in seven cervical intraepithelial neoplasia (CIN) and 43 primary CA-CX samples using 20 highly polymorphic microsatellite markers. RESULTS: Deletions of chromosome 3 were significantly associated with tumour progression. High frequencies (33-53%) of loss of heterozygosity (LOH) were found in 3p26.1, 3p22.3, 3p21.2, and 3p13, suggesting the location of putative tumour suppressor genes (TSGs) in these regions. Among these four regions, deletions in 3p21.2 were suggested to occur early during CA-CX development. A significant correlation was found between LOH at 3p26.1 and 3p22.3 with tumour progression from stage I/IIB to stage III/IV. No association was found with the highly deleted regions and human papillomavirus positivity, parity, or menopausal status. Microsatellite size alteration was seen in only seven of the samples. However, rare biallelic alterations were seen in and around the highly deleted regions. Loss of normal copy of chromosome 3 and interstitial alterations in chromosome 3p were seen in some samples. CONCLUSION: These four regions on chromosome 3p may be differentially deleted during specific stages of CA-CX development. The putative TSGs located in these regions may have a cumulative effect on tumour progression.


Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 3/genética , Displasia do Colo do Útero/genética , Neoplasias do Colo do Útero/genética , Adulto , Idoso , Progressão da Doença , Feminino , Humanos , Perda de Heterozigosidade , Repetições de Microssatélites , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/complicações , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/virologia , Displasia do Colo do Útero/patologia , Displasia do Colo do Útero/virologia
15.
Int J Gynecol Cancer ; 13(4): 472-9, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12911724

RESUMO

In our analysis, alterations in the P16 tumor suppressor gene were seen in 33% (15/46) of sampled uterine cervical lesions. Among the alterations, mutations in P16 were detected in 15% (7/46) of the samples. One mutation occurred at intron 1/exon 2 splice junction. All the other mutations were in exon 2 with three of them as silent mutations. The promoter hypermethylation and homozygous deletion of P16 gene were detected in 6.5% (3/46) and 8.7% (4/46) of the samples respectively. Loss of heterozygosity and microsatellite size alterations at the P16 locus were seen in 17% (8/46) of the samples. HPV16/18 infection was detected in 76% (35/46) of the samples. But no association was found between P16 alterations and HPV infection. Thus, it seems that P16 inactivation may be associated with the development of some uterine cervical carcinoma.


Assuntos
Carcinoma/genética , Regulação Neoplásica da Expressão Gênica , Predisposição Genética para Doença , Mutação , Neoplasias do Colo do Útero/genética , Adulto , Idoso , Alelos , Sequência de Bases , Biópsia por Agulha , Carcinoma/patologia , Distribuição de Qui-Quadrado , DNA de Neoplasias , Feminino , Genes p16 , Humanos , Imuno-Histoquímica , Índia , Pessoa de Meia-Idade , Dados de Sequência Molecular , Estadiamento de Neoplasias , Reação em Cadeia da Polimerase , Probabilidade , Prognóstico , Estudos de Amostragem , Sensibilidade e Especificidade , Neoplasias do Colo do Útero/patologia
16.
J Exp Clin Cancer Res ; 22(2): 289-97, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12866580

RESUMO

In the deletion mapping of chromosome (chr) 9 in head and neck lesions of the Indian patient population by microsatellite markers, we have identified four discrete areas (D1-D4) with high loss of heterozygosities (LOHs) viz. 9p24-p23 (D1), 9p22-p21 (D2), 9q11-q13 (D3) and 9q22.3 (D4) regions. The deletions in D2 and D4 regions were suggested to be essential for the development of dysplastic lesions of head and neck, whereas the deletions in D1 and D3 regions were responsible for progression of the dysplastic lesions to early invasive head and neck squamous cell carcinoma (HNSCC). The microsatellite size alterations (MAs) were observed in the chromosomal 9pter-p23, 9p22-p21(D2), 9q13 and 9q21.1-q21.2 regions with gradual increase during progression of the tumor. Additional chromosomal alterations like loss of normal copy of chr.9 and biallelic alterations were also seen in our samples. There is a correlation between HPV infection with TNM stages, histopathological grades and LOHs at D1 and D4 regions. Whereas tobacco habit is associated with the occurrence of LOHs at D1 and LOHs / MAs at D2 region.


Assuntos
Carcinoma de Células Escamosas/genética , Deleção Cromossômica , Cromossomos Humanos Par 9 , Neoplasias de Cabeça e Pescoço/genética , Adolescente , Adulto , Idoso , Carcinoma de Células Escamosas/virologia , Progressão da Doença , Feminino , Deleção de Genes , Marcadores Genéticos , Neoplasias de Cabeça e Pescoço/virologia , História Moderna 1601- , Humanos , Índia , Perda de Heterozigosidade , Masculino , Repetições de Microssatélites , Pessoa de Meia-Idade , Papillomaviridae/metabolismo
17.
Oral Oncol ; 38(1): 6-15, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11755815

RESUMO

The candidate tumor suppressor genes' (TSG) loci on human chromosome 3 (chr.3) were mapped in six dysplastic lesions and 51 primary squamous cell carcinoma from head and neck region of an Indian patient population by using 20 highly polymorphic microsatellite markers. The two chromosomal regions 3p12-13 and 3p21.2-22 have shown the highest losses of heterozygosity (LOHs) of 34.6-38% and 37-46%, respectively with statistically significant clinical correlation's with tobacco habit, positive lymph node and tumor stages. In addition, high frequencies of microsatellite size alterations (MAs) of 16.2-28.5% and 23.8-28.2% were observed in the chromosomal 3p11-13 and 3p21.2-22 regions, respectively, with significant above-mentioned clinical correlation only in the 3p11-13 region. In the dysplastic lesions, the prevalence of LOHs compared to the MAs had indicated that LOHs might be the early events. Five tumors at stage-III/IV seemed to have lost an entire normal copy of chr.3. It was of particular note that 17% (10/57) of the samples showed rare bi-allelic alterations mainly in and around the high LOHs regions. Thus, (1) the gradual increase of LOHs/MAs during progression of the tumor, (2) high frequencies of MAs, (3) rare bi-allelic alterations in and around high LOHs regions and (4) loss of wild type chr.3 in the later stages of tumor development have suggested that such alterations might provide selective growth advantage to the tumors. Also, we propose from our data that the high LOHs regions (3p12-13 and 3p21.2-22) could harbour putative TSG(s), responsible for the development of head and neck squamous cell carcinoma.


Assuntos
Carcinoma de Células Escamosas/genética , Mapeamento Cromossômico , Cromossomos Humanos Par 3/genética , Genes Supressores de Tumor/fisiologia , Neoplasias de Cabeça e Pescoço/genética , Adulto , Idoso , Carcinoma de Células Escamosas/patologia , Distribuição de Qui-Quadrado , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Índia/etnologia , Perda de Heterozigosidade , Masculino , Repetições de Microssatélites , Pessoa de Meia-Idade , Estadiamento de Neoplasias/métodos , Reação em Cadeia da Polimerase , Fumar/efeitos adversos , População Branca/genética
18.
J Clin Invest ; 108(6): 887-94, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11560958

RESUMO

Epstein-Barr virus-associated lymphoproliferative disease (EBV-LPD) is a potentially life-threatening complication in immune-deficient patients. We have used the severe combined immune deficient (SCID) mouse engrafted with human leukocytes (hu-PBL-SCID) to evaluate the use of human cytokines in the prevention of EBV-LPD in vivo. Daily low-dose IL-2 therapy can prevent EBV-LPD in the hu-PBL-SCID mouse, but protection is lost if murine natural killer (NK) cells are depleted. Here we demonstrate that combined therapy with human GM-CSF and low-dose IL-2 is capable of preventing EBV-LPD in the hu-PBL-SCID mouse in the absence of murine NK cells. Lymphocyte depletion experiments showed that human NK cells, CD8(+) T cells, and monocytes were each required for the protective effects of GM-CSF and IL-2 combination therapy. This treatment resulted in a marked expansion of human CD3(+)CD8(+) lymphocytes in vivo. Using HLA tetramers complexed with EBV immunodominant peptides, a subset of these lymphocytes was found to be EBV-specific. These data establish that combined GM-CSF and low-dose IL-2 therapy can prevent the immune deficiencies that lead to fatal EBV-LPD in the hu-PBL-SCID mouse depleted of murine NK cells, and they point to a critical role for several human cellular subsets in mediating this protective effect.


Assuntos
Infecções por Vírus Epstein-Barr/prevenção & controle , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Interleucina-2/farmacologia , Transtornos Linfoproliferativos/prevenção & controle , Animais , Modelos Animais de Doenças , Infecções por Vírus Epstein-Barr/imunologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/administração & dosagem , Humanos , Imunidade Celular/efeitos dos fármacos , Interleucina-2/administração & dosagem , Células Matadoras Naturais/imunologia , Transfusão de Leucócitos , Transtornos Linfoproliferativos/imunologia , Camundongos , Camundongos SCID , Subpopulações de Linfócitos T/efeitos dos fármacos , Subpopulações de Linfócitos T/imunologia , Transplante Heterólogo
19.
Nitric Oxide ; 5(2): 137-49, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11292363

RESUMO

Previous studies showed that proanthocyanidins provide potent protection against oxidative stress. Here we investigate the effects of grape seed proanthocyanidin extract (GSPE) as a novel natural antioxidant on the generation and fate of nitric oxide (NO) in rat primary glial cell cultures. GSPE treatment (50 mg/L) increased NO production (measured by NO(2-) assay) by stimulation of the inducible isoform of NOS. However, GSPE failed to affect the LPS/IFN-gamma-induced NO production or iNOS expression. Similar responses were found in the murine macrophage cell line RAW264.7. GSPE did not show any effect on dihydrodichlorofluorescein fluorescence (ROS marker with high sensitivity toward peroxynitrite) either in control or in LPS/IFN-gamma-induced glial cultures even in the presence of a superoxide generator (PMA). GSPE treatment alone had no effect on the basal glutathione (GSH) status in glial cultures. Whereas the microglial GSH level declined sharply after LPS/IFN-gamma treatment, the endogenous GSH pool was protected when such cultures were treated additionally with GSPE, although NO levels did not change. Glial cultures pretreated with GSPE showed higher tolerance toward application of hydrogen peroxide (H(2)O(2)) and tert-butylhydroperoxide. Furthermore, GSPE-pretreated glial cultures showed improved viability after H(2)O(2)-induced oxidative stress demonstrated by reduction in lactate dehydrogenase release or propidium iodide staining. We showed that, in addition to its antioxidative property, GSPE enhances low-level production of intracellular NO in primary rat astroglial cultures. Furthermore, GSPE pretreatment protects the microglial GSH pool during high output NO production and results in an elevation of the H(2)O(2) tolerance in astroglial cells.


Assuntos
Antocianinas/farmacologia , Neuroglia/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Proantocianidinas , Rosales , Sementes , Animais , Antioxidantes/farmacologia , Células Cultivadas , Glutationa/metabolismo , Peróxido de Hidrogênio/farmacologia , Peróxido de Hidrogênio/toxicidade , Imuno-Histoquímica , Interferon gama/farmacologia , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/enzimologia , Macrófagos/metabolismo , Camundongos , Microscopia de Fluorescência , Neuroglia/enzimologia , Neuroglia/metabolismo , Nitratos/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/imunologia , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo II , Nitrosação/efeitos dos fármacos , Oxidantes/farmacologia , Oxidantes/toxicidade , Ratos , Ratos Wistar , terc-Butil Hidroperóxido/farmacologia
20.
J Clin Psychiatry ; 62 Suppl 2: 12-6, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11232745

RESUMO

Acute, high-dose loading strategies (rapid neuroleptization) with the first-generation antipsychotics administered orally or parenterally, alone or combined with benzodiazepines, have been a commonly used treatment paradigm for controlling acutely agitated psychotic patients. The rationale was to achieve high plasma levels of drug within a shorter time period, resulting in rapid symptom mitigation. However, studies have shown that rapid neuroleptization with first-generation antipsychotics is associated with a greater incidence of side effects. To our knowledge, loading strategies with second-generation antipsychotics have not been investigated, primarily owing to a need for dose titration. Olanzapine, a second-generation antipsychotic, is well tolerated in doses ranging from 5 to 20 mg. The objective of this report was to determine experience with the use of up to 20 mg of an oral loading dose of olanzapine administered within 4 hours in the treatment of patients early in an acute psychotic phase of their illness. In the reported case series of 57 patients, olanzapine initiated at 15 to 20 mg/day was a safe and effective medication for rapidly calming the agitation of acutely agitated psychotic patients (rapid tranquilization). Furthermore, dose reduction over 2 to 3 weeks was achieved in a number of patients without appreciable loss of efficacy.


Assuntos
Antipsicóticos/uso terapêutico , Pirenzepina/análogos & derivados , Pirenzepina/uso terapêutico , Transtornos Psicóticos/tratamento farmacológico , Doença Aguda , Antipsicóticos/administração & dosagem , Antipsicóticos/efeitos adversos , Doenças dos Gânglios da Base/induzido quimicamente , Doenças dos Gânglios da Base/epidemiologia , Benzodiazepinas , Esquema de Medicação , Humanos , Incidência , Olanzapina , Pirenzepina/administração & dosagem , Pirenzepina/efeitos adversos , Escalas de Graduação Psiquiátrica/estatística & dados numéricos , Transtornos Psicóticos/psicologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA