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1.
Nat Commun ; 14(1): 6646, 2023 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-37863907

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-36462464

RESUMEN

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.


Asunto(s)
Neoplasias de los Conductos Biliares , Colangiocarcinoma , Glioma , Neoplasias de la Vejiga Urinaria , Humanos , Conductos Biliares Intrahepáticos , Biomarcadores de Tumor/genética , Colangiocarcinoma/genética , Genómica , Glioma/genética , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/genética , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/genética , Proteínas Tirosina Quinasas Receptoras/metabolismo
3.
Acta Crystallogr F Struct Biol Commun ; 75(Pt 5): 359-367, 2019 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-31045565

RESUMEN

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.


Asunto(s)
Proteínas Bacterianas/química , Proteínas del Citoesqueleto/química , Mycobacterium tuberculosis/química , Subunidades de Proteína/química , Secuencia de Aminoácidos , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Sitios de Unión , División Celular , Clonación Molecular , Cristalografía por Rayos X , Proteínas del Citoesqueleto/genética , Proteínas del Citoesqueleto/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Expresión Génica , Vectores Genéticos/química , Vectores Genéticos/metabolismo , Cinética , Modelos Moleculares , Mutación , Unión Proteica , Conformación Proteica en Hélice alfa , Conformación Proteica en Lámina beta , Dominios y Motivos de Interacción de Proteínas , Multimerización de Proteína , Subunidades de Proteína/genética , Subunidades de Proteína/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Homología Estructural de Proteína , Temperatura
4.
Interv Neuroradiol ; 19(2): 235-9, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23693049

RESUMEN

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.


Asunto(s)
Traumatismos de las Arterias Carótidas/etiología , Traumatismos de las Arterias Carótidas/cirugía , Cateterismo Periférico/efectos adversos , Embolización Terapéutica/instrumentación , Embolización Terapéutica/métodos , Trombolisis Mecánica/instrumentación , Trombina/administración & dosificación , Anciano , Traumatismos de las Arterias Carótidas/diagnóstico por imagen , Terapia Combinada , Hemostáticos/administración & dosificación , Humanos , Inyecciones Subcutáneas , Masculino , Trombolisis Mecánica/métodos , Radiografía , Resultado del Tratamiento
5.
Interv Neuroradiol ; 19(2): 250-3, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23693052

RESUMEN

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.


Asunto(s)
Carcinoma de Células Renales/secundario , Carcinoma de Células Renales/terapia , Dolor/prevención & control , Sacro/cirugía , Neoplasias de la Columna Vertebral/secundario , Neoplasias de la Columna Vertebral/terapia , Vertebroplastia/métodos , Anciano , Carcinoma de Células Renales/etiología , Terapia Combinada , Criocirugía/métodos , Embolización Terapéutica/métodos , Etanol/uso terapéutico , Hemostáticos/uso terapéutico , Humanos , Masculino , Dolor/etiología , Soluciones Esclerosantes/uso terapéutico , Neoplasias de la Columna Vertebral/complicaciones , Resultado del Tratamiento
6.
Parasitology ; 138(3): 267-78, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20880419

RESUMEN

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.


Asunto(s)
Bases de Datos de Ácidos Nucleicos , Ácidos Grasos/metabolismo , Giardia lamblia/metabolismo , Metabolismo de los Lípidos/genética , Proteínas Protozoarias/genética , Animales , Genoma/genética , Giardia lamblia/genética , Giardiasis/parasitología , Humanos , Proteínas Protozoarias/metabolismo
7.
J Maxillofac Oral Surg ; 10(2): 170-2, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22654373

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-16803484

RESUMEN

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.


Asunto(s)
Carcinoma/radioterapia , Carcinoma/virología , Recurrencia Local de Neoplasia/epidemiología , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/epidemiología , Neoplasias del Cuello Uterino/radioterapia , Neoplasias del Cuello Uterino/virología , Adulto , Cuidados Posteriores/estadística & datos numéricos , Anciano , Femenino , Humanos , Persona de Mediana Edad , Infecciones por Papillomavirus/sangre , Infecciones por Papillomavirus/complicaciones , Prevalencia , Sensibilidad y Especificidad , Análisis de Supervivencia , Neoplasias del Cuello Uterino/mortalidad , Frotis Vaginal , Carga Viral/estadística & datos numéricos
10.
Acta Crystallogr C ; 61(Pt 4): o201-3, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15805624

RESUMEN

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.


Asunto(s)
Cortisona/análogos & derivados , Cortisona/química , Cristalografía por Rayos X , Enlace de Hidrógeno , Modelos Moleculares , Conformación Molecular
11.
Gynecol Oncol ; 95(2): 352-62, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15491757

RESUMEN

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.


Asunto(s)
Aberraciones Cromosómicas , Cromosomas Humanos Par 8/genética , Neoplasias del Cuello Uterino/genética , Adulto , Anciano , Mapeo Cromosómico , Femenino , Genes Supresores de Tumor , Genes myc/genética , Predisposición Genética a la Enfermedad , Humanos , India , Pérdida de Heterocigocidad , Persona de Mediana Edad , Papillomaviridae , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/genética , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/virología
12.
Exp Mol Pathol ; 76(3): 264-71, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15126110

RESUMEN

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.


Asunto(s)
Neoplasias de la Mama/genética , Cromosomas Humanos Par 8/genética , Fibroadenoma/genética , Adulto , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/patología , ADN de Neoplasias/genética , Femenino , Fibroadenoma/epidemiología , Fibroadenoma/patología , Genes Supresores de Tumor , Humanos , India/epidemiología , Pérdida de Heterocigocidad , Repeticiones de Microsatélite
13.
Indian J Med Res ; 118: 77-85, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-14680203

RESUMEN

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.


Asunto(s)
Carcinoma de Células Escamosas/genética , Deleción Cromosómica , Cromosomas Humanos Par 8 , Neoplasias de Cabeza y Cuello/genética , Alelos , Secuencia de Bases , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/virología , Cartilla de ADN , Femenino , Neoplasias de Cabeza y Cuello/patología , Neoplasias de Cabeza y Cuello/virología , Humanos , India , Pérdida de Heterocigocidad , Masculino , Papillomaviridae/aislamiento & purificación
14.
Mol Pathol ; 56(5): 263-9, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14514919

RESUMEN

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.


Asunto(s)
Deleción Cromosómica , Cromosomas Humanos Par 3/genética , Displasia del Cuello del Útero/genética , Neoplasias del Cuello Uterino/genética , Adulto , Anciano , Progresión de la Enfermedad , Femenino , Humanos , Pérdida de Heterocigocidad , Repeticiones de Microsatélite , Persona de Mediana Edad , Estadificación de Neoplasias , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/complicaciones , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/virología , Displasia del Cuello del Útero/patología , Displasia del Cuello del Útero/virología
15.
Int J Gynecol Cancer ; 13(4): 472-9, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12911724

RESUMEN

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.


Asunto(s)
Carcinoma/genética , Regulación Neoplásica de la Expresión Génica , Predisposición Genética a la Enfermedad , Mutación , Neoplasias del Cuello Uterino/genética , Adulto , Anciano , Alelos , Secuencia de Bases , Biopsia con Aguja , Carcinoma/patología , Distribución de Chi-Cuadrado , ADN de Neoplasias , Femenino , Genes p16 , Humanos , Inmunohistoquímica , India , Persona de Mediana Edad , Datos de Secuencia Molecular , Estadificación de Neoplasias , Reacción en Cadena de la Polimerasa , Probabilidad , Pronóstico , Muestreo , Sensibilidad y Especificidad , Neoplasias del Cuello Uterino/patología
16.
J Exp Clin Cancer Res ; 22(2): 289-97, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12866580

RESUMEN

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.


Asunto(s)
Carcinoma de Células Escamosas/genética , Deleción Cromosómica , Cromosomas Humanos Par 9 , Neoplasias de Cabeza y Cuello/genética , Adolescente , Adulto , Anciano , Carcinoma de Células Escamosas/virología , Progresión de la Enfermedad , Femenino , Eliminación de Gen , Marcadores Genéticos , Neoplasias de Cabeza y Cuello/virología , Historia Moderna 1601- , Humanos , India , Pérdida de Heterocigocidad , Masculino , Repeticiones de Microsatélite , Persona de Mediana Edad , Papillomaviridae/metabolismo
17.
Oral Oncol ; 38(1): 6-15, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11755815

RESUMEN

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.


Asunto(s)
Carcinoma de Células Escamosas/genética , Mapeo Cromosómico , Cromosomas Humanos Par 3/genética , Genes Supresores de Tumor/fisiología , Neoplasias de Cabeza y Cuello/genética , Adulto , Anciano , Carcinoma de Células Escamosas/patología , Distribución de Chi-Cuadrado , Femenino , Neoplasias de Cabeza y Cuello/patología , Humanos , India/etnología , Pérdida de Heterocigocidad , Masculino , Repeticiones de Microsatélite , Persona de Mediana Edad , Estadificación de Neoplasias/métodos , Reacción en Cadena de la Polimerasa , Fumar/efectos adversos , Población Blanca/genética
18.
J Clin Invest ; 108(6): 887-94, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11560958

RESUMEN

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.


Asunto(s)
Infecciones por Virus de Epstein-Barr/prevención & control , Factor Estimulante de Colonias de Granulocitos y Macrófagos/farmacología , Interleucina-2/farmacología , Trastornos Linfoproliferativos/prevención & control , Animales , Modelos Animales de Enfermedad , Infecciones por Virus de Epstein-Barr/inmunología , Factor Estimulante de Colonias de Granulocitos y Macrófagos/administración & dosificación , Humanos , Inmunidad Celular/efectos de los fármacos , Interleucina-2/administración & dosificación , Células Asesinas Naturales/inmunología , Transfusión de Leucocitos , Trastornos Linfoproliferativos/inmunología , Ratones , Ratones SCID , Subgrupos de Linfocitos T/efectos de los fármacos , Subgrupos de Linfocitos T/inmunología , Trasplante Heterólogo
19.
Nitric Oxide ; 5(2): 137-49, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11292363

RESUMEN

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.


Asunto(s)
Antocianinas/farmacología , Neuroglía/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/farmacología , Proantocianidinas , Rosales , Semillas , Animales , Antioxidantes/farmacología , Células Cultivadas , Glutatión/metabolismo , Peróxido de Hidrógeno/farmacología , Peróxido de Hidrógeno/toxicidad , Inmunohistoquímica , Interferón gamma/farmacología , Lipopolisacáridos/farmacología , Macrófagos/efectos de los fármacos , Macrófagos/enzimología , Macrófagos/metabolismo , Ratones , Microscopía Fluorescente , Neuroglía/enzimología , Neuroglía/metabolismo , Nitratos/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa/antagonistas & inhibidores , Óxido Nítrico Sintasa/inmunología , Óxido Nítrico Sintasa/metabolismo , Óxido Nítrico Sintasa de Tipo II , Nitrosación/efectos de los fármacos , Oxidantes/farmacología , Oxidantes/toxicidad , Ratas , Ratas Wistar , terc-Butilhidroperóxido/farmacología
20.
J Clin Psychiatry ; 62 Suppl 2: 12-6, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11232745

RESUMEN

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.


Asunto(s)
Antipsicóticos/uso terapéutico , Pirenzepina/análogos & derivados , Pirenzepina/uso terapéutico , Trastornos Psicóticos/tratamiento farmacológico , Enfermedad Aguda , Antipsicóticos/administración & dosificación , Antipsicóticos/efectos adversos , Enfermedades de los Ganglios Basales/inducido químicamente , Enfermedades de los Ganglios Basales/epidemiología , Benzodiazepinas , Esquema de Medicación , Humanos , Incidencia , Olanzapina , Pirenzepina/administración & dosificación , Pirenzepina/efectos adversos , Escalas de Valoración Psiquiátrica/estadística & datos numéricos , Trastornos Psicóticos/psicología
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