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1.
Genomics ; 114(5): 110478, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36064073

RESUMEN

Stomach cancer is the fifth most common cancer in terms of prevalence and incidence and the fourth leading cause of mortality in men and women worldwide. It is well-established that aberrant DNA methylation in cells can lead to carcinogenesis. The primary objective of our study was to investigate the aberrant DNA methylation status of genes associated with stomach cancer with a particular reference to the ethnic population of Mizoram, North East India. The site-level analysis identified 2883 CpG sites differentially methylated, representing ∼922 genes. Out of which 476 Differentially Methylated Positions (DMPs) were promoter-associated, 452 DMPs were hypermethylated, and 24 were hypomethylated. The region-level analysis identified 462 Differentially Methylated Regions (DMRs) corresponding to ∼320 genes, of which ∼281 genes were hypermethylated and âˆ¼40 genes were hypomethylated. TCGA analysis showed that some of the genes had been previously implicated in other cancers including stomach cancer. Five hypermethylated genes were selected as candidate genes for further investigations and they have shown to be novel and could serve as candidate hypermethylation biomarkers for stomach cancer in this particular ethnic group.


Asunto(s)
Metilación de ADN , Neoplasias Gástricas , Islas de CpG , Epigénesis Genética , Etnicidad , Femenino , Humanos , India , Masculino , Neoplasias Gástricas/genética
2.
Ann Oncol ; 29(1): 223-229, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29045505

RESUMEN

Background: Detection of circulating tumor DNA can be limited due to their relative scarcity in circulation, particularly while patients are actively undergoing therapy. Exosomes provide a vehicle through which cancer-specific material can be enriched from the compendium of circulating non-neoplastic tissue-derived nucleic acids. We carried out a comprehensive profiling of the pancreatic ductal adenocarcinoma (PDAC) exosomal 'surfaceome' in order to identify surface proteins that will render liquid biopsies amenable to cancer-derived exosome enrichment for downstream molecular profiling. Patients and methods: Surface exosomal proteins were profiled in 13 human PDAC and 2 non-neoplastic cell lines by liquid chromatography-mass spectrometry. A total of 173 prospectively collected blood samples from 103 PDAC patients underwent exosome isolation. Droplet digital PCR was used on 74 patients (136 total exosome samples) to determine baseline KRAS mutation call rates while patients were on therapy. PDAC-specific exosome capture was then carried out on additional 29 patients (37 samples) using an antibody cocktail directed against selected proteins, followed by droplet digital PCR analysis. Exosomal DNA in a PDAC patient resistant to therapy were profiled using a molecular barcoded, targeted sequencing panel to determine the utility of enriched nucleic acid material for comprehensive molecular analysis. Results: Proteomic analysis of the exosome 'surfaceome' revealed multiple PDAC-specific biomarker candidates: CLDN4, EPCAM, CD151, LGALS3BP, HIST2H2BE, and HIST2H2BF. KRAS mutations in total exosomes were detected in 44.1% of patients undergoing active therapy compared with 73.0% following exosome capture using the selected biomarkers. Enrichment of exosomal cargo was amenable to molecular profiling, elucidating a putative mechanism of resistance to PARP inhibitor therapy in a patient harboring a BRCA2 mutation. Conclusion: Exosomes provide unique opportunities in the context of liquid biopsies for enrichment of tumor-specific material in circulation. We present a comprehensive surfaceome characterization of PDAC exosomes which allows for capture and molecular profiling of tumor-derived DNA.


Asunto(s)
Carcinoma Ductal Pancreático/diagnóstico , Exosomas/química , Proteínas de Neoplasias/análisis , Neoplasias Pancreáticas/diagnóstico , Biomarcadores de Tumor/sangre , Carcinoma Ductal Pancreático/sangre , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patología , Línea Celular Tumoral , Cromatografía Liquida , Análisis Mutacional de ADN , Exosomas/metabolismo , Humanos , Biopsia Líquida/métodos , Proteínas de Neoplasias/sangre , Neoplasias Pancreáticas/sangre , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patología , Medicina de Precisión , Proteómica , Espectrometría de Masas en Tándem
3.
Ann Oncol ; 28(4): 741-747, 2017 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-28104621

RESUMEN

Background: Exosomes arise from viable cancer cells and may reflect a different biology than circulating cell-free DNA (cfDNA) shed from dying tissues. We compare exosome-derived DNA (exoDNA) to cfDNA in liquid biopsies of patients with pancreatic ductal adenocarcinoma (PDAC). Patients and methods: Patient samples were obtained between 2003 and 2010, with clinically annotated follow up to 2015. Droplet digital PCR was performed on exoDNA and cfDNA for sensitive detection of KRAS mutants at codons 12/13. A cumulative series of 263 individuals were studied, including a discovery cohort of 142 individuals: 68 PDAC patients of all stages; 20 PDAC patients initially staged with localized disease, with blood drawn after resection for curative intent; and 54 age-matched healthy controls. A validation cohort of 121 individuals (39 cancer patients and 82 healthy controls) was studied to validate KRAS detection rates in early-stage PDAC patients. Primary outcome was circulating KRAS status as detected by droplet digital PCR. Secondary outcomes were disease-free and overall survival. Results: KRAS mutations in exoDNA, were identified in 7.4%, 66.7%, 80%, and 85% of age-matched controls, localized, locally advanced, and metastatic PDAC patients, respectively. Comparatively, mutant KRAS cfDNA was detected in 14.8%, 45.5%, 30.8%, and 57.9% of these individuals. Higher exoKRAS MAFs were associated with decreased disease-free survival in patients with localized disease. In the validation cohort, mutant KRAS exoDNA was detected in 43.6% of early-stage PDAC patients and 20% of healthy controls. Conclusions: Exosomes are a distinct source of tumor DNA that may be complementary to other liquid biopsy DNA sources. A higher percentage of patients with localized PDAC exhibited detectable KRAS mutations in exoDNA than previously reported for cfDNA. A substantial minority of healthy samples demonstrated mutant KRAS in circulation, dictating careful consideration and application of liquid biopsy findings, which may limit its utility as a broad cancer-screening method.


Asunto(s)
Carcinoma Ductal Pancreático/genética , ADN de Neoplasias/sangre , Detección Precoz del Cáncer/métodos , Neoplasias Pancreáticas/genética , Proteínas Proto-Oncogénicas p21(ras)/genética , Adulto , Anciano , Biomarcadores de Tumor/sangre , Biomarcadores de Tumor/genética , Carcinoma Ductal Pancreático/sangre , Carcinoma Ductal Pancreático/patología , ADN de Neoplasias/genética , Supervivencia sin Enfermedad , Exosomas/genética , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Mutación , Neoplasias Pancreáticas/sangre , Neoplasias Pancreáticas/patología , Modelos de Riesgos Proporcionales , Reacción en Cadena en Tiempo Real de la Polimerasa , Neoplasias Pancreáticas
4.
Support Care Cancer ; 25(6): 1809-1817, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28111717

RESUMEN

BACKGROUND: Cachexia is a frequent manifestation of pancreatic cancer, can limit a patient's ability to take chemotherapy, and is associated with shortened survival. We developed a model to predict the early onset of cachexia in advanced pancreatic cancer patients. METHODS: Patients with newly diagnosed, untreated metastatic or locally advanced pancreatic cancer were included. Serum cytokines were drawn prior to therapy. Patient symptoms were recorded using the M.D. Anderson Symptom Inventory (MDASI). Our primary endpoint was either 10% weight loss or death within 60 days of the start of therapy. RESULTS: Twenty-seven of 89 patients met the primary endpoint (either having lost 10% of body weight or having died within 60 days of the start of treatment). In a univariate analysis, smoking, history symptoms of pain and difficulty swallowing, high levels of MK, CXCL-16, IL-6, TNF-a, and low IL-1b all correlated with this endpoint. We used recursive partition to fit a regression tree model, selecting four of 26 variables (CXCL-16, IL-1b, pain, swallowing difficulty) as important in predicting cachexia. From these, a model of two cytokines (CXCL-16 > 5.135 ng/ml and IL-1b < 0.08 ng/ml) demonstrated a better sensitivity and specificity for this outcome (0.70 and 0.86, respectively) than any individual cytokine or tumor marker. CONCLUSIONS: Cachexia is frequent in pancreatic cancer; one in three patients met our endpoint of 10% weight loss or death within 60 days. Inflammatory cytokines are better than conventional tumor markers at predicting this outcome. Recursive partitioning analysis suggests that a model of CXCL-16 and IL-1B may offer a better ability than individual cytokines to predict this outcome.


Asunto(s)
Biomarcadores de Tumor/sangre , Caquexia/sangre , Citocinas/sangre , Inflamación/sangre , Neoplasias Pancreáticas/complicaciones , Medición de Resultados Informados por el Paciente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/patología
5.
Ann Oncol ; 27(4): 635-41, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26681674

RESUMEN

BACKGROUND: The ability to perform comprehensive profiling of cancers at high resolution is essential for precision medicine. Liquid biopsies using shed exosomes provide high-quality nucleic acids to obtain molecular characterization, which may be especially useful for visceral cancers that are not amenable to routine biopsies. PATIENTS AND METHODS: We isolated shed exosomes in biofluids from three patients with pancreaticobiliary cancers (two pancreatic, one ampullary). We performed comprehensive profiling of exoDNA and exoRNA by whole genome, exome and transcriptome sequencing using the Illumina HiSeq 2500 sequencer. We assessed the feasibility of calling copy number events, detecting mutational signatures and identifying potentially actionable mutations in exoDNA sequencing data, as well as expressed point mutations and gene fusions in exoRNA sequencing data. RESULTS: Whole-exome sequencing resulted in 95%-99% of the target regions covered at a mean depth of 133-490×. Genome-wide copy number profiles, and high estimates of tumor fractions (ranging from 56% to 82%), suggest robust representation of the tumor DNA within the shed exosomal compartment. Multiple actionable mutations, including alterations in NOTCH1 and BRCA2, were found in patient exoDNA samples. Further, RNA sequencing of shed exosomes identified the presence of expressed fusion genes, representing an avenue for elucidation of tumor neoantigens. CONCLUSIONS: We have demonstrated high-resolution profiling of the genomic and transcriptomic landscapes of visceral cancers. A wide range of cancer-derived biomarkers could be detected within the nucleic acid cargo of shed exosomes, including copy number profiles, point mutations, insertions, deletions, gene fusions and mutational signatures. Liquid biopsies using shed exosomes has the potential to be used as a clinical tool for cancer diagnosis, therapeutic stratification and treatment monitoring, precluding the need for direct tumor sampling.


Asunto(s)
Biomarcadores de Tumor/genética , Proteínas de Neoplasias/genética , Neoplasias Pancreáticas/genética , Anciano , Biomarcadores de Tumor/biosíntesis , Exoma/genética , Exosomas/genética , Femenino , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Persona de Mediana Edad , Mutación , Proteínas de Neoplasias/biosíntesis , Neoplasias Pancreáticas/patología
6.
Br J Cancer ; 113(1): 64-8, 2015 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-25989273

RESUMEN

BACKGROUND: Outcomes for ampullary adenocarcinomas are heterogeneous, and numerous methods of categorisation exist. A histomolecular phenotype based on histology, caudal-type homeodomain transcription factor 2 (CDX2) staining and Mucin 1 (MUC1) staining has recently been tested and validated in two cohorts. We attempt to validate this classification in a large patient population. METHODS: Tissue samples from 163 patients with resected ampullary adenocarcinoma were classified based on histology and immunohistochemical expression of CDX2 and MUC1. A pancreaticobiliary histomolecular classification (PB) was defined as a sample with pancreaticobiliary histology, positive MUC1 and negative CDX2 expression. RESULTS: There were 82 deaths; median follow-up of 32.4 months; and median overall survival of 87.7 (95% CI 42.9-109.5) months. PB comprised 28.2% of the cases. Factors associated with overall survival were histological subtype (P=0.0340); T1/2 vs T3/4 (P=0.001); perineural (P<0.0001) and lymphovascular (P=0.0203) invasion; and histomolecular intestinal histomolecular phenotype (INT) vs PB phenotype (106.4 vs 21.2 months, P<0.0001). Neither MUC1 nor CDX2 was statistically significant, although MUC1 positivity defined as ⩾10% staining was significant (P=0.0023). In multivariate analysis, age (HR 1.03), PB phenotype (HR 2.26) and perineural invasion (PNI; HR 2.26) were associated with poor survival. CONCLUSIONS: The prognostic ability of histomolecular phenotype has been validated in an independent cohort of ampullary adenocarcinoma patients.


Asunto(s)
Adenocarcinoma/patología , Ampolla Hepatopancreática/patología , Neoplasias del Conducto Colédoco/patología , Proteínas de Homeodominio/metabolismo , Mucina-1/metabolismo , Adenocarcinoma/metabolismo , Adenocarcinoma/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Factor de Transcripción CDX2 , Estudios de Cohortes , Neoplasias del Conducto Colédoco/metabolismo , Neoplasias del Conducto Colédoco/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico
7.
Phys Rev Lett ; 114(9): 098302, 2015 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-25793858

RESUMEN

A paradigm for internally driven matter is the active nematic liquid crystal, whereby the equations of a conventional nematic are supplemented by a minimal active stress that violates time-reversal symmetry. In practice, active fluids may have not only liquid-crystalline but also viscoelastic polymer degrees of freedom. Here we explore the resulting interplay by coupling an active nematic to a minimal model of polymer rheology. We find that adding a polymer can greatly increase the complexity of spontaneous flow, but can also have calming effects, thereby increasing the net throughput of spontaneous flow along a pipe (a "drag-reduction" effect). Remarkably, active turbulence can also arise after switching on activity in a sufficiently soft elastomeric solid.


Asunto(s)
Modelos Biológicos , Modelos Químicos , Sustancias Viscoelásticas/química , Bacterias/química , Fenómenos Fisiológicos Bacterianos , Cristales Líquidos/química , Reología/métodos , Natación
8.
Minerva Gastroenterol Dietol ; 61(2): 51-9, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25675155

RESUMEN

Pancreatic ductal adenocarcinoma is a lethal cancer with a 5-year survival rate of less than 5%. Surgical resection is the only curative treatment but only 20% are eligible for resection at the time of diagnosis. Early detection of cancer is of paramount importance in the management. Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is the preferred modality for obtaining tissue diagnosis of pancreatic masses. However, the diagnostic accuracy of EUS-FNA may be limited by several factors like availability of onsite cytopathology, adequacy of tissue core for histology, location of the mass, presence of underlying chronic pancreatitis, and experience of the endoscopist. Modern oncology is focusing on personalizing treatment based on tissue analysis of genetic aberrations and molecular biomarkers which are now available. Core tissue also aids in the diagnosis of disease entities like lymphoma, metastatic tumors, neuroendocrine tumors and autoimmune pancreatitis whose diagnosis rely on preserved tissue architecture and immunohistochemistry. Making accurate diagnosis of solid pancreatic masses is critical to avoid unnecessary resections in patients with benign lesions like focal lesions of chronic pancreatitis and autoimmune pancreatitis which mimic cancer. To overcome the limitations of FNA and to obtain adequate core tissue, a Tru-Cut biopsy needle was developed which met with variable success due to stiffness, cumbersome operation and technical failure using it in the duodenum/pancreatic head. More recently fine needle biopsy needles, with reverse bevel technology have become available in different sizes (19, 22, 25-gauge). The aim of this article was to review the emerging role of core biopsy needles in acquiring tissue in solid pancreatic masses and discuss its potential role in personalized medicine.


Asunto(s)
Biopsia por Aspiración con Aguja Fina Guiada por Ultrasonido Endoscópico , Neoplasias Pancreáticas/patología , Humanos , Neoplasias Pancreáticas/diagnóstico por imagen
10.
Genetika ; 49(4): 505-12, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23866627

RESUMEN

The calpains and calpastatin (CAST) make up a major cytosolic proteolytic system, the calpain-calpastatin system, found in mammalian tissues. The relative levels of the components of the calpain-calpastatin system determine the extent of meat tenderization during postmortem storage. Calpastatin (CAST) is a protein inhibitor of the ubiquitous calcium-dependent proteases-micro-calpain and m-calpain. Polymorphisms in the bovine, ovine and pig CAST gene have been associated with meat tenderness but little is known about how caprine CAST gene may affect goat meat quality traits. In this study we selected different parts of the CAST gene: 1) that have been previously reported to be polymorphic, intron 5 and 12 and 3'UTR; 2) first time explored (exon 3, 7 and 8 and part of intron 7 and 8) to investigate polymorphic status of caprine CAST gene. Using comparative sequencing ten novel SN Ps located in exon 3 and intron 5, 7 and 8 were identified. Previously reported SNPs in intron 5, 3'UTR and intron 12 were absent. Sequence analysis revealed a non synonymous amino acid variation in exon 3, which would result in Lys/Arg substitution in the corresponding protein sequence. Considerable variation was detected in intronic regions. Twenty-four InDel were also recognized in intronic regions (15) and 3'UTR (9). All the sequences shared high homology with published bovine and ovine sequences. Three PCR-RFLP loci have been established for further analyzing genetic polymorphism in indigenous goats.


Asunto(s)
Proteínas de Unión al Calcio/genética , Cabras/genética , Polimorfismo de Nucleótido Simple , Regiones no Traducidas 3' , Sustitución de Aminoácidos , Animales , Exones , India , Intrones , Carne , Polimorfismo de Longitud del Fragmento de Restricción
11.
Neurol Perspect ; 3(4)2023.
Artículo en Inglés | MEDLINE | ID: mdl-38124707

RESUMEN

Background: Obstructive sleep apnea is a highly prevalent disorder, characterized by recurrent events of upper airway obstruction during sleep and associated with recurrent cycles of desaturation and re-oxygenation, sympathetic hyperactivity, and intra-thoracic pressure fluctuations, resulting in fragmentation of sleep and subsequent daytime fatigue with excessive sleepiness. Obstructive sleep apnea-induced bilateral tonic-clonic seizures are unheard of. We aimed to report 3 patients with previously undiagnosed obstructive sleep apnea who presented to the emergency department with new onset bilateral tonic-clonic seizure without any evidential neurological or metabolic cause. Methods: Patient data were obtained from medical records from the Department of Internal Medicine, IPGMER and SSKM Hospital, Kolkata, and Belle Vue Clinic, Kolkata, India. Results: Three male patients (67, 58, and 44 years old) presented with bilateral tonic-clonic seizure disorder without any underlying cause of seizures after rigorous investigations except for moderate to severe obstructive sleep apnea on polysomnography. All 2 patients were seizure-free after being treated with levetiracetam, chronic continuous positive airway pressure therapy in 2, and only continuous positive airway pressure in the other. The patients remained seizure-free on continuous positive airway pressure, even when levetiracetam was withdrawn, suggesting obstructive sleep apnea's causality in their new-onset acute seizures. Conclusion: Although further investigation is required to clarify this association, underlying obstructive sleep apnea should be ruled out in patients with a first-ever bilateral tonic-clonic seizure. Whether or not continuous positive airway pressure alone could effectively treat hypoxia and deranged cortical excitability, which may lead to seizures in cases with longstanding obstructive sleep apnea, is yet to be explored.


Introducción: La apnea obstructiva del sueño es una enfermedad con una alta prevalencia que se caracteriza por episodios recurrentes de obstrucción de las vías respiratorias altas durante el sueño, lo que conlleva ciclos repetidos de hipoxia y reoxigenación, hiperactividad simpática y fluctuaciones en la presión intratorácica. Todos estos procesos dan lugar a una fragmentación del sueño, lo que provoca fatiga diurna y somnolencia excesiva. Las crisis tónico-clónicas bilaterales inducidas por apnea obstructiva del sueño son poco conocidas. Presentamos los casos de tres pacientes con apnea obstructiva del sueño sin diagnosticar previamente que acudieron a urgencias por crisis tónico-clónicas de nueva aparición sin causa neurológica o metabólica aparente. Métodos: Los datos de nuestros pacientes se recogieron de los historiales médicos del servicio de Medicina Interna del Institute of Post-Graduate Medical Education and Research and Seth Sukhlal Karnani Memorial Hospital y de la Belle Vue Clinic, ambos en Kolkata (India). Resultados: Tres pacientes varones de 67, 58 y 44 años de edad presentaron convulsiones tónico-clónicas bilaterales sin causa identificada tras examen riguroso, exceptuando una apnea obstructiva del sueño de gravedad moderada a grave observada en la polisomnografía. Los tres pacientes recibieron tratamiento con levetiracetam durante el ingreso; al alta, se pautó tratamiento crónico con presión positiva continua de las vías respiratorias más levetiracetam en dos pacientes, y en el tercero solo presión positiva continua de las vías respiratorias. Ninguno presentó nuevas crisis tras la retirada de levetiracetam, lo que sugiere que la causa de las convulsiones era la apnea obstructiva del sueño. Conclusión: Aunque es necesario realizar más estudios para aclarar esta asociación, debemos descartar la apnea obstructiva del sueño en pacientes con crisis tónico-clónicas bilaterales de nueva aparición. Queda aún por determinar si la presión positiva continua podría tratar de forma efectiva la hipoxia y las alteraciones en la excitabilidad cortical, que podrían provocar crisis en casos de apnea obstructiva del sueño de larga evolución.

12.
Dis Esophagus ; 25(7): 630-7, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22221671

RESUMEN

Barrett's esophagus (BE) is a premalignant condition with an increased risk of developing esophageal adenocarcinoma (EAC). Risk factors for EAC overlap with those for esophageal squamous cell carcinoma (ESCC), but ESCC is surprisingly rare in BE. We report two cases of ESCC directly surrounded by BE. Both patients had a previous medical history of cancers, i.e., head and neck squamous cell carcinomas, and were using alcohol and smoking tobacco. Using immunohistochemistry for p63, CK5, CK7, and CDX2, it was confirmed that these carcinomas were pure squamous cell carcinomas, and not EACs or esophageal adenosquamous carcinomas arising from BE. Using TP53 mutation and loss of heterozygosity analysis, we established that the ESCCs in BE were not metastases of the previously diagnosed head and neck squamous cell carcinomas but de novo primary ESCCs. This study shows the strength of molecular analysis as an adjunct to the histopathologic diagnosis for distinguishing between metastases of prior cancers and primary cancers. Furthermore, these cases imply that presence of BE is not protective with regards to developing ESCC in the lower one third of the esophagus. We suggest that their ESCCs arose from islets of squamous epithelium in BE.


Asunto(s)
Esófago de Barrett/complicaciones , Biomarcadores de Tumor/metabolismo , Carcinoma de Células Escamosas/complicaciones , Neoplasias Esofágicas/complicaciones , Anciano , Esófago de Barrett/patología , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patología , Carcinoma de Células Escamosas de Esófago , Humanos , Inmunohistoquímica , Masculino , Metástasis de la Neoplasia
13.
Genetika ; 48(6): 719-25, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22946330

RESUMEN

Cattle are the most important livestock in India and play a pivotal role in agrarian economy. There are 34 recognized breeds of cattle and number of unexplored lesser known populations. The present study is a contribution towards determining genetic variation and understanding the relationship among four lesser known populations. A total of 194 unrelated DNA samples from three cattle populations of Orissa (Binjharpuri, Ghumsuri, Motu) and Hill cattle of Kumaun (Kumauni) were collected from respective breeding tracts. Genotyping was done with 23 bovine microsatellite markers as suggested by International Society for Animal Genetics (ISAG) and FAO (DAD-IS) on automated sequencer. The average observed heterozygosity in the four populations lie within the narrow range of 0.623 +/- 0.04 in Binjharpuri to 0.664 +/- 0.03 in Kumauni. Mean estimates of observed and expected heterozygosity over all loci and breeds were 0.651 +/- 0.02 and 0.720 +/- 0.01, respectively. In the overall population, the homozygote excess (F(IT)) of 0.132 +/- 0.03, was partly due to the genetic differentiation among breeds (F(ST) = 0.044 +/- 0.01) and, to a larger extent, to a significant homozygote excess within breeds (F(IS) = 0.094 +/- 0.03). The phylogenetic reconstruction from a UPGMA clustering based on Nei's Standard genetic distance yielded a tree with Binjharpuri and Ghumsuri on a single node and Motu and Kumauni on separate nodes. The most probable clustering detected by STRUCTURE in population was three. Binjharpuri and Ghumsuri animals were assigned to one cluster with high proportion of membership.


Asunto(s)
Bovinos/genética , ADN/genética , Repeticiones de Microsatélite/genética , Animales , Cruzamiento , Filogenia
14.
Indian J Exp Biol ; 48(10): 1043-52, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21299047

RESUMEN

Nanobiotechnology focuses on the biological effects and applications of nanoparticles that include nano-safety, drug encapsulation and nanotherapeutics. The present study focuses on hydrophilic nanospheres of copolymers N-isopropylacrylamide [NIPAAM] and vinyl pyrrolidone [VP], encapsulating a bioactive derivative of 5-fluorouracil-hexyl-carbamoyl fluorouracil (HCFU). The size of the nanospheres was approximately 58 nm and the surface charge measured was -15.4 mV. Under optimal conditions, the yield was >80%, and the drug loading was 2%. The entrapment efficiency was approximately 75%. Wide-angle X-ray diffraction analysis showed that the entrapped HCFU was present in an amorphous state, which has higher water solubility compared with the crystalline state. Slow drug release from nanospheres was observed in PBS and serum, with approximately 80% released at 37 degrees C after 72 h. The HCFU loaded polymeric nanospheres have been found to be stable in whole blood having negligible RBC toxicity. Cytotoxicity in Mia-Paca 3, pancreatic cancer cell line was done in a 24-72 h assay. Dose dependant cytotoxicity was observed when incubated with various concentrations of HCFU loaded polymeric nanospheres while HCFU per se (<1 mg) showed 90% toxicity within 24 h.


Asunto(s)
Sistemas de Liberación de Medicamentos , Nanosferas , Acrilamidas/química , Antineoplásicos/administración & dosificación , Antineoplásicos/farmacocinética , Línea Celular Tumoral , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Fluorouracilo/administración & dosificación , Fluorouracilo/análogos & derivados , Fluorouracilo/farmacocinética , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Nanosferas/química , Polímeros/química , Povidona/química
15.
Thorax ; 64(4): 321-5, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19286764

RESUMEN

OBJECTIVE: To investigate whether duration of television (TV) viewing in young children is associated with subsequent development of asthma. METHODS: Children taking part in the Avon Longitudinal Study of Parents and Children (ALSPAC) with no wheeze up to the age of 3.5 years and follow-up data at 11.5 years of age took part in a prospective longitudinal cohort study. The main outcome measure was asthma, defined as doctor-diagnosed asthma by 7.5 years of age with symptoms and/or treatment in the previous 12 months at 11.5 years of age. Parental report of hours of TV viewing per day by the children was ascertained at 39 months. RESULTS: In children with no symptoms of wheeze at 3.5 years of age and follow-up data at 11.5 years of age, the prevalence of asthma was 6% (185/3065). Increased TV viewing at 3.5 years was associated with increased prevalence of asthma at 11.5 years of age (p for linear trend = 0.0003). Children who watched television for >2 h/day were almost twice as likely to develop asthma by 11.5 years of age as those watching TV for 1-2 h/day (adjusted odds ratio 1.8 (95% CI 1.2 to 2.6)). CONCLUSION: Longer duration of TV viewing in children with no symptoms of wheeze at 3.5 years of age was associated with the development of asthma in later childhood.


Asunto(s)
Asma/etiología , Televisión/estadística & datos numéricos , Asma/epidemiología , Asma/fisiopatología , Hiperreactividad Bronquial/etiología , Niño , Preescolar , Inglaterra/epidemiología , Ejercicio Físico/fisiología , Femenino , Conductas Relacionadas con la Salud , Humanos , Masculino , Prevalencia , Estudios Prospectivos , Distribución por Sexo , Factores de Tiempo
16.
Gut ; 57(10): 1420-30, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18515410

RESUMEN

BACKGROUND AND AIMS: Pancreatic cancer is among the most dismal of human malignancies. Current therapeutic strategies are virtually ineffective in controlling advanced, metastatic disease. Recent evidence suggests that the Hedgehog signalling pathway is aberrantly reactivated in the majority of pancreatic cancers, and that Hedgehog blockade has the potential to prevent disease progression and metastatic spread. METHODS: Here it is shown that the Hedgehog pathway is activated in the Pdx1-Cre;LsL-Kras(G12D);Ink4a/Arf(lox/lox) transgenic mouse model of pancreatic cancer. The effect of Hedgehog pathway inhibition on survival was determined by continuous application of the small molecule cyclopamine, a smoothened antagonist. Microarray analysis was performed on non-malignant human pancreatic ductal cells overexpressing Gli1 in order to screen for downstream Hedgehog target genes likely to be involved in pancreatic cancer progression. RESULTS: Hedgehog inhibition with cyclopamine significantly prolonged median survival in the transgenic mouse model used here (67 vs 61 days; p = 0.026). In vitro data indicated that Hedgehog activation might at least in part be ascribed to oncogenic Kras signalling. Microarray analysis identified 26 potential Hedgehog target genes that had previously been found to be overexpressed in pancreatic cancer. Five of them, BIRC3, COL11A1, NNMT, PLAU and TGM2, had been described as upregulated in more than one global gene expression analysis before. CONCLUSION: This study provides another line of evidence that Hedgehog signalling is a valid target for the development of novel therapeutics for pancreatic cancer that might be worth evaluating soon in a clinical setting.


Asunto(s)
Carcinoma Ductal Pancreático/tratamiento farmacológico , Proteínas Hedgehog/antagonistas & inhibidores , Proteínas de Neoplasias/antagonistas & inhibidores , Neoplasias Pancreáticas/tratamiento farmacológico , Alcaloides de Veratrum/administración & dosificación , Ensayos Antitumor por Modelo de Xenoinjerto , Animales , Carcinoma Ductal Pancreático/mortalidad , Carcinoma Ductal Pancreático/patología , Proliferación Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Proteínas Hedgehog/metabolismo , Humanos , Ratones , Ratones Transgénicos , Análisis de Secuencia por Matrices de Oligonucleótidos , Neoplasias Pancreáticas/mortalidad , Neoplasias Pancreáticas/patología , Distribución Aleatoria , Transducción de Señal/efectos de los fármacos , Análisis de Supervivencia , Células Tumorales Cultivadas , Regulación hacia Arriba
17.
J Inherit Metab Dis ; 31 Suppl 2: S317-22, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18690553

RESUMEN

Congenital generalized lipodystrophy (CGL) is an autosomal recessive metabolic syndrome with involvement of multiple organs. Mutations in BSCL2 are known to be associated with a severe form of CGL and mental retardation (MR). The genetic heterogeneity in CGL patients is accompanied by phenotypic heterogeneity in different ethnic groups. Studies in the Indian context are very few in this regard. We report here a detailed clinical analysis of a CGL case from infancy to adult hood. Interestingly, the patient was found to be homozygous for a novel BSCL2 mutation, but with normal intellectual development contrasting with the MR associated with BSCL2 mutation in CGL patients. The biochemical investigations at the time of diagnosis (9 months) included total cholesterol, total lipids, triglycerides, phospholipids, ß-lipoprotein and free fatty acids, which were above normal limits. The clinical phenotype, viz. lack of subcutaneous fat, hepatosplenomegaly, cardiomegaly, and advanced bone age was also documented. The patient was found to be insulin resistant and diabetes mellitus was diagnosed by age 13 years. Ultrasonography of the ovaries at age 22 showed polycystic features with elevated levels of gonadotropins and negligible levels of serum leptin. For genetic analysis, direct DNA sequencing of BSCL2 was carried out and disclosed an 11-base-pair deletion in exon 6 (H217fsX272) resulting in a truncated protein. This is a novel mutation that contributes to CGL formation in a family of Indian origin and adds to the array of variants reported in this disorder. Moreover, the novel mutation is found to be associated with normal intellectual ability.


Asunto(s)
Subunidades gamma de la Proteína de Unión al GTP/genética , Lipodistrofia Generalizada Congénita/genética , Eliminación de Secuencia , Adolescente , Adulto , Niño , Desarrollo Infantil , Preescolar , Análisis Mutacional de ADN , Progresión de la Enfermedad , Exones , Resultado Fatal , Femenino , Predisposición Genética a la Enfermedad , Homocigoto , Humanos , India , Lactante , Inteligencia , Lipodistrofia Generalizada Congénita/complicaciones , Lipodistrofia Generalizada Congénita/diagnóstico , Lipodistrofia Generalizada Congénita/psicología , Fenotipo , Insuficiencia Renal/etiología , Adulto Joven
18.
Indian J Exp Biol ; 45(10): 843-52, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17948732

RESUMEN

Mycobacterium avium subspecies paratuberculosis (MAP) is the etiological agent of paratuberculosis, a chronic gastroenteritis of ruminants and has zoonotic importance. We present here a review of MAP with respect to--(i) present diagnostic techniques and important developments; and (ii) MAP strain-typing tools. A summary of the findings to date is presented, and advantages and disadvantages of each of the methods are compared and discussed.


Asunto(s)
Mycobacterium avium/clasificación , Mycobacterium avium/fisiología , Paratuberculosis/clasificación , Paratuberculosis/diagnóstico , Animales , Humanos , Inmunidad Innata/inmunología , Mycobacterium avium/aislamiento & purificación , Paratuberculosis/inmunología , Paratuberculosis/microbiología
19.
Oncogene ; 36(22): 3149-3158, 2017 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-27991926

RESUMEN

Chronic inflammation (CI) is a risk factor for pancreatic cancer (PC) including the most common type, ductal adenocarcinoma (PDAC), but its role and the mechanisms involved are unclear. To investigate the role of CI in PC, we generated genetic mouse models with pancreatic specific CI in the presence or absence of TP53. Mice were engineered to express either cyclooxygenase-2 (COX-2) or IκB kinase-2 (IKK2), and TP53+/+ or TP53f/f specifically in adult pancreatic acinar cells by using a full-length pancreatic elastase promoter-driven Cre. Animals were followed for >80 weeks and pancreatic lesions were evaluated histologically and immunohistochemically. The presence of K-ras mutations was assessed by direct sequencing, locked nuclei acid (LNA)-based PCR, and immunohistochemistry. We observed that sustained COX-2/IKK2 expression caused histological abnormalities of pancreas, including increased immune cell infiltration, proliferation rate and DNA damage. A minority of animals with CI developed pre-neoplastic lesions, but cancer was not observed in any TP53+/+ animals within 84 weeks. In contrast, all animals with CI-lacking TP53 developed various subtypes of PC, including acinar cell carcinoma, ductal adenocarcinoma, sarcomatoid carcinoma and neuroendocrine tumors, and all died within 65 weeks. No evidence of K-ras mutations was observed. Variations in the activity of the Hippo, pERK and c-Myc pathways were found in the diverse cancer subtypes. In summary, chronic inflammation is extremely inefficient at inducing PC in the presence of TP53. However, in the absence of TP53, CI leads to the development of several rare K-ras-independent forms of PC, with infrequent PDAC. This may help explain the rarity of PDAC in persons with chronic inflammatory conditions.


Asunto(s)
Carcinoma Ductal Pancreático/patología , Inflamación/patología , Neoplasias Pancreáticas/patología , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Animales , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Enfermedad Crónica , Modelos Animales de Enfermedad , Genes ras , Inflamación/genética , Inflamación/metabolismo , Ratones , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteína p53 Supresora de Tumor/genética
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