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1.
Nature ; 588(7837): 331-336, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33299191

RESUMEN

Most deaths from cancer are explained by metastasis, and yet large-scale metastasis research has been impractical owing to the complexity of in vivo models. Here we introduce an in vivo barcoding strategy that is capable of determining the metastatic potential of human cancer cell lines in mouse xenografts at scale. We validated the robustness, scalability and reproducibility of the method and applied it to 500 cell lines1,2 spanning 21 types of solid tumour. We created a first-generation metastasis map (MetMap) that reveals organ-specific patterns of metastasis, enabling these patterns to be associated with clinical and genomic features. We demonstrate the utility of MetMap by investigating the molecular basis of breast cancers capable of metastasizing to the brain-a principal cause of death in patients with this type of cancer. Breast cancers capable of metastasizing to the brain showed evidence of altered lipid metabolism. Perturbation of lipid metabolism in these cells curbed brain metastasis development, suggesting a therapeutic strategy to combat the disease and demonstrating the utility of MetMap as a resource to support metastasis research.


Asunto(s)
Neoplasias de la Mama/patología , Movimiento Celular , Metástasis de la Neoplasia/patología , Especificidad de Órganos , Animales , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/secundario , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Procesamiento Automatizado de Datos , Femenino , Xenoinjertos , Humanos , Metabolismo de los Lípidos/genética , Ratones , Tipificación Molecular , Mutación , Metástasis de la Neoplasia/genética , Trasplante de Neoplasias , Proyectos Piloto
2.
Clin Genet ; 105(3): 302-307, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38018277

RESUMEN

The evolutionarily conserved mevalonate pathway plays an important role in the synthesis of cholesterol and isoprenoid compounds. Mevalonate kinase (MVK) and phosphomevalonate kinase (PMVK) enzymes regulate key rate-limiting steps in this pathway by sequentially phosphorylating mevalonic acid to yield downstream metabolites that regulate protein prenylation and cell signaling. Biallelic pathogenic variants in MVK cause a spectrum of rare autoinflammatory disorders that encompass milder forms of hyper-IgD syndrome (HIDS) at one end and the more severe mevalonic aciduria on the other. In contrast, pathogenic variants reported in PMVK are heterozygous and associated with porokeratosis, a skin disorder with no systemic manifestations. Recently, biallelic variants in PMVK were reported as a cause for an autoinflammatory disorder for the first time in two unrelated patients. In this study, we describe a child with recurrent arthritis and a HIDS-like phenotype harboring a novel homozygous variant c.398 C>T (p.Ala133Val) in PMVK. Mononuclear cells isolated from the patient showed significantly elevated production of interleukin 1ß, a key cytokine that shapes the inflammatory response in HIDS. Protein modeling studies suggested potential defects in PMVK enzyme activity. These results posit a further expanding of the genotypic spectrum of autoinflammatory disease to include biallelic PMVK variants.


Asunto(s)
Deficiencia de Mevalonato Quinasa , Niño , Humanos , Genotipo , Deficiencia de Mevalonato Quinasa/genética , Deficiencia de Mevalonato Quinasa/metabolismo , Fenotipo , Fosfotransferasas (Aceptor de Grupo Alcohol)/genética , Fosfotransferasas (Aceptor de Grupo Alcohol)/metabolismo , Fosfotransferasas (Aceptor del Grupo Fosfato)/genética
3.
Clin Genet ; 105(6): 639-654, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38374498

RESUMEN

The application of genomic technologies has led to unraveling of the complex genetic landscape of disorders of epilepsy, gaining insights into their underlying disease mechanisms, aiding precision medicine, and providing informed genetic counseling. We herein present the phenotypic and genotypic insights from 142 Indian families with epilepsy with or without comorbidities. Based on the electroclinical findings, epilepsy syndrome diagnosis could be made in 44% (63/142) of the families adopting the latest proposal for the classification by the ILAE task force (2022). Of these, 95% (60/63) of the families exhibited syndromes with developmental epileptic encephalopathy or progressive neurological deterioration. A definitive molecular diagnosis was achieved in 74 of 142 (52%) families. Infantile-onset epilepsy was noted in 81% of these families (61/74). Fifty-five monogenic, four chromosomal, and one imprinting disorder were identified in 74 families. The genetic variants included 65 (96%) single-nucleotide variants/small insertion-deletions, 1 (2%) copy-number variant, and 1 (2%) triplet-repeat expansion in 53 epilepsy-associated genes causing monogenic disorders. Of these, 35 (52%) variants were novel. Therapeutic implications were noted in 51% of families (38/74) with definitive diagnosis. Forty-one out of 66 families with monogenic disorders exhibited autosomal recessive and inherited autosomal dominant disorders with high risk of recurrence.


Asunto(s)
Epilepsia , Asesoramiento Genético , Fenotipo , Humanos , Epilepsia/genética , Epilepsia/epidemiología , Epilepsia/diagnóstico , India/epidemiología , Masculino , Femenino , Niño , Preescolar , Lactante , Predisposición Genética a la Enfermedad , Linaje , Edad de Inicio , Estudios de Asociación Genética , Adolescente , Genotipo , Variaciones en el Número de Copia de ADN/genética
4.
Am J Med Genet A ; 194(5): e63529, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38179855

RESUMEN

Nucleoporins (NUPs) are a group of transporter proteins that maintain homeostasis of nucleocytoplasmic transport of proteins and ribonucleic acids under physiological conditions. Biallelic pathogenic variants in NUP214 are known to cause susceptibility to acute infection-induced encephalopathy-9 (IIAE9, MIM#618426), which is characterized by severe and early-onset febrile encephalopathy causing neuroregression, developmental delay, microcephaly, epilepsy, ataxia, brain atrophy, and early death. NUP214-related IIAE9 has been reported in eight individuals from four distinct families till date. We identified a novel in-frame deletion, c.202_204del p.(Leu68del), in NUP214 by exome sequencing in a 20-year-old male with episodic ataxia, seizures, and encephalopathy, precipitated by febrile illness. Neuroimaging revealed progressive cerebellar atrophy. In silico predictions show a change in the protein conformation that may alter the downstream protein interactions with the NUP214 N-terminal region, probably impacting the mRNA export. We report this novel deletion in NUP214 as a cause for a late onset and less severe form of IIAE9.


Asunto(s)
Encefalopatía Aguda Febril , Encefalopatías , Epilepsia , Microcefalia , Masculino , Humanos , Adulto Joven , Adulto , Encefalopatías/diagnóstico , Encefalopatías/genética , Epilepsia/genética , Microcefalia/genética , Atrofia , Proteínas de Complejo Poro Nuclear/genética
6.
Clin Genet ; 100(5): 542-550, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34302356

RESUMEN

Genetic disorders with predominant central nervous system white matter abnormalities (CNS WMAs), also called leukodystrophies, are heterogeneous entities. We ascertained 117 individuals with CNS WMAs from 104 unrelated families. Targeted genetic testing was carried out in 16 families and 13 of them received a diagnosis. Chromosomal microarray (CMA) was performed for three families and one received a diagnosis. Mendeliome sequencing was used for testing 11 families and all received a diagnosis. Whole exome sequencing (WES) was performed in 80 families and was diagnostic in 52 (65%). Singleton WES was diagnostic for 50/75 (66.67%) families. Overall, genetic diagnoses were obtained in 77 families (74.03%). Twenty-two of 47 distinct disorders observed in this cohort have not been reported in Indian individuals previously. Notably, disorders of nuclear mitochondrial pathology were most frequent (9 disorders in 20 families). Thirty-seven of 75 (49.33%) disease-causing variants are novel. To sum up, the present cohort describes the phenotypic and genotypic spectrum of genetic disorders with CNS WMAs in our population. It demonstrates WES, especially singleton WES, as an efficient tool in the diagnosis of these heterogeneous entities. It also highlights possible founder events and recurrent disease-causing variants in our population and their implications on the testing strategy.


Asunto(s)
Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Malformaciones del Sistema Nervioso/diagnóstico , Malformaciones del Sistema Nervioso/genética , Sustancia Blanca/anomalías , Alelos , Aberraciones Cromosómicas , Consanguinidad , Familia , Estudios de Asociación Genética/métodos , Pruebas Genéticas , Humanos , India/epidemiología , Análisis por Micromatrices , Mutación , Malformaciones del Sistema Nervioso/epidemiología , Secuenciación del Exoma
7.
Int J Paediatr Dent ; 30(6): 805-815, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32248585

RESUMEN

BACKGROUND: The stainless steel crowns (SSCs) placed using the Hall technique disrupt the occlusion, but stabilization appears to occur within a short period post-placement. Negligible understanding and comprehension is presently handy about the changes in overbite and bite force after placement of stainless steel crown using the Hall technique in children. AIM/HYPOTHESIS: To evaluate the digital occlusal analysis of vertical dimension and maximum intercuspal position to understand the changes in overbite and bite force after placement of stainless steel crown using the Hall technique. DESIGN: Twenty children who needed treatment for the carious tooth with decay extending to enamel and dentin and multisurface caries were managed using the Hall technique. Following that, overbite measurement for vertical dimension was carried out clinically using digital vernier calipers. Later, the T-Scan III was used for measuring occlusal load at the maximum intercuspal position. The bite force and occlusal premature contacts were digitally analysed and recorded pre-operatively, immediately after placement of SSC and after 1 month follow-up period. RESULTS: A significant result in the vertical dimension, bite force on crowned tooth, and significant reduction in the prematurities were seen from baseline to one-month follow-up. CONCLUSION: There was an occlusal re-equilibration attained after 1 month.


Asunto(s)
Acero Inoxidable , Diente Primario , Niño , Coronas , Humanos , Diente Molar , Dimensión Vertical
8.
AAPS PharmSciTech ; 18(5): 1495-1506, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28078629

RESUMEN

The present study was aimed to investigate the effect of salient microneedle (MN) geometry parameters like length, density, shape and type on transdermal permeation of rizatriptan (RIZ). Studies were carried out using two types of MN devices viz. AdminPatch® arrays (ADM) (0.6, 0.9, 1.2 and 1.5 mm lengths) and laboratory-fabricated polymeric MNs (PMs) of 0.6 mm length. In the case of the PMs, arrays were applied three times at different places within a 1.77-cm2 skin area (PM-3) to maintain the MN density closer to 0.6 mm ADM. Histological studies revealed that PM, owing to their geometry/design, formed wider and deeper microconduits when compared to ADM of similar length. Approximately 4.9- and 4.2-fold increases in the RIZ steady-state flux values were observed with 1.5 mm ADM and PM-3 applications when compared to the passive studies. A good correlation between different dimensionless parameters like the amount of RIZ permeated (C t /C s), thickness (h/L) and surface area (S a/L 2) of the skin was observed with scaling analyses. Numerical simulations provided further information regarding the distribution of RIZ in MN-treated skin after application of different MNs. Overall, the study suggests that MN application enhances the RIZ transdermal permeation and the geometrical parameters of MNs play an important role in the degree enhancement.


Asunto(s)
Agujas/normas , Triazoles , Triptaminas , Administración Cutánea , Sistemas de Liberación de Medicamentos/instrumentación , Análisis Numérico Asistido por Computador , Agonistas de Receptores de Serotonina/química , Agonistas de Receptores de Serotonina/farmacocinética , Piel/patología , Absorción Cutánea , Triazoles/química , Triazoles/farmacocinética , Triptaminas/química , Triptaminas/farmacocinética
9.
Tomography ; 10(5): 693-704, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38787014

RESUMEN

Despite their relatively low incidence globally, central nervous system (CNS) tumors remain amongst the most lethal cancers, with only a few other malignancies surpassing them in 5-year mortality rates. Treatment decisions for brain tumors heavily rely on histopathological analysis, particularly intraoperatively, to guide surgical interventions and optimize patient outcomes. Frozen sectioning has emerged as a vital intraoperative technique, allowing for highly accurate, rapid analysis of tissue samples, although it poses challenges regarding interpretive errors and tissue distortion. Raman histology, based on Raman spectroscopy, has shown great promise in providing label-free, molecular information for accurate intraoperative diagnosis, aiding in tumor resection and the identification of neurodegenerative disease. Techniques including Stimulated Raman Scattering (SRS), Coherent Anti-Stokes Raman Scattering (CARS), Surface-Enhanced Raman Scattering (SERS), and Tip-Enhanced Raman Scattering (TERS) have profoundly enhanced the speed and resolution of Raman imaging. Similarly, Confocal Laser Endomicroscopy (CLE) allows for real-time imaging and the rapid intraoperative histologic evaluation of specimens. While CLE is primarily utilized in gastrointestinal procedures, its application in neurosurgery is promising, particularly in the context of gliomas and meningiomas. This review focuses on discussing the immense progress in intraoperative histology within neurosurgery and provides insight into the impact of these advancements on enhancing patient outcomes.


Asunto(s)
Neoplasias Encefálicas , Procedimientos Neuroquirúrgicos , Espectrometría Raman , Humanos , Espectrometría Raman/métodos , Procedimientos Neuroquirúrgicos/métodos , Neoplasias Encefálicas/cirugía , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/diagnóstico por imagen , Glioma/patología , Glioma/cirugía , Glioma/diagnóstico por imagen , Microscopía Confocal/métodos
10.
Clin Dysmorphol ; 32(4): 162-167, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37646703

RESUMEN

Congenital myasthenic syndromes (CMS) are rare, heterogeneous, and often treatable genetic disorders depending on the underlying molecular defect. We performed a detailed clinical evaluation of seven patients from five unrelated families. Exome sequencing was performed on five index patients. Clinically significant variants were identified in four CMS disease-causing genes: COLQ (3/7), CHRNE (2/7), DOK7 (1/7), and RAPSN (1/7). We identified two novel variants, c.930_933delCATG in DOK7 and c.1016_1032 + 2dup in CHRNE . A common pathogenic variant, c.955-2A>C, has been identified in COLQ -related CMS patients. Homozygosity mapping of this COLQ variant in patients from two unrelated families revealed that it was located in a common homozygous region of 3.2 Mb on chromosome 3 and was likely to be inherited from a common ancestor. Patients with COLQ variants had generalized muscle weakness, those with DOK7 and RAPSN variants had limb-girdle weakness, and those with CHRNE variants had predominant ocular weakness. Patients with COLQ and DOK7 variants showed improvement with salbutamol and CHRNE with pyridostigmine therapy. This study expands the mutational spectrum and adds a small but significant cohort of CMS patients from India. We also reviewed the literature to identify genetic subtypes of CMS in India.


Asunto(s)
Síndromes Miasténicos Congénitos , Humanos , Albuterol , Pueblo Asiatico/genética , Cromosomas Humanos Par 3 , Síndromes Miasténicos Congénitos/diagnóstico , Síndromes Miasténicos Congénitos/genética , Personas del Sur de Asia/genética
11.
Eur J Hum Genet ; 2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-38114583

RESUMEN

The contribution of de novo variants as a cause of intellectual disability (ID) is well established in several cohorts reported from the developed world. However, the genetic landscape as well as the appropriate testing strategies for identification of de novo variants of these disorders remain largely unknown in low-and middle-income countries like India. In this study, we delineate the clinical and genotypic spectrum of 54 families (55 individuals) with syndromic ID harboring rare de novo variants. We also emphasize on the effectiveness of singleton exome sequencing as a valuable tool for diagnosing these disorders in resource limited settings. Overall, 46 distinct disorders were identified encompassing 46 genes with 51 single-nucleotide variants and/or indels and two copy-number variants. Pathogenic variants were identified in CREBBP, TSC2, KMT2D, MECP2, IDS, NIPBL, NSD1, RIT1, SOX10, BRWD3, FOXG1, BCL11A, KDM6B, KDM5C, SETD5, QRICH1, DCX, SMARCD1, ASXL1, ASXL3, AKT3, FBN2, TCF12, WASF1, BRAF, SMARCA4, SMARCA2, TUBG1, KMT2A, CTNNB1, DLG4, MEIS2, GATAD2B, FBXW7, ANKRD11, ARID1B, DYNC1H1, HIVEP2, NEXMIF, ZBTB18, SETD1B, DYRK1A, SRCAP, CASK, L1CAM, and KRAS. Twenty-four of these monogenic disorders have not been previously reported in the Indian population. Notably, 39 out of 53 (74%) disease-causing variants are novel. These variants were identified in the genes mainly encoding transcriptional and chromatin regulators, serine threonine kinases, lysosomal enzymes, molecular motors, synaptic proteins, neuronal migration machinery, adhesion molecules, structural proteins and signaling molecules.

12.
Indian J Pediatr ; 89(6): 594-596, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35032020

RESUMEN

Biotinidase deficiency (BD) is an autosomal recessive disorder caused by bi-allelic mutation in the BTD gene. Clinical manifestations in BD mainly depends on residual biotinidase enzyme activity, although there are some exceptions. Broadly BD disorders are classified as profound BD and partial BD. Further profound BD can be early onset, late onset, and sometimes may be asymptomatic. Clinically late-onset profound BD can present with spectrum of manifestations ranging from single organ to multiple organ involvement, typically affecting function of brain, eye, ear, and skin. Here, a first-born child to consanguineous parents with late-onset profound BD presenting with hyperventilation secondary to lactic acidosis, hypotonia, evolving spasticity, and abnormal neuroimaging findings caused by novel homozygous variant, c.466-3T>G in the BTD gene is reported.


Asunto(s)
Deficiencia de Biotinidasa , Alelos , Biotinidasa/genética , Deficiencia de Biotinidasa/diagnóstico , Deficiencia de Biotinidasa/genética , Niño , Homocigoto , Humanos , Mutación
13.
Polymers (Basel) ; 11(8)2019 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-31412588

RESUMEN

This is a study of the modelling and prediction of strain recovery in a polylactide. Strain recovery near the glass transition temperature is the underlying mechanism for the shape memory in an amorphous polymer. The investigation is aimed at modelling such shape memory behaviour. A PLA-based copolymer is subjected to stress-strain, stress relaxation and strain recovery experiments at large strain at 60 °C just below its glass transition temperature. The material is 13% crystalline. Using published data on the mechanical properties of the crystals, finite element modelling was used to determine the effect of the crystal phase on the overall mechanical behaviour of the material, which was found to be significant. The finite element models were also used to relate the stress-strain results to the yield stress of the amorphous phase. This yield stress was found to possess strain rate dependence consistent with an Eyring process. Stress relaxation experiments were also interpreted in terms of the Eyring process, and a two-process Eyring-based model was defined that was capable of modelling strain recovery behaviour. This was essentially a model of the amorphous phase. It was shown to be capable of useful predictions of strain recovery.

14.
Drug Deliv Transl Res ; 7(3): 383-394, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28160258

RESUMEN

The present study aimed to investigate the effect of microneedle (MN) geometry parameters like length, density, shape and type on transdermal permeation enhancement of amlodipine (AMLO). Two types of MN devices viz. AdminPatch® arrays (ADM) (0.6, 1.2 and 1.5 mm lengths) and laboratory-fabricated polymeric MNs (PM) of 0.6 mm length were employed. In the case of PMs, arrays were applied thrice at different places within a 1.77-cm2 skin area (PM-3) to maintain the MN density closer to 0.6 mm ADM. Scaling analyses were done using dimensionless parameters like concentration of AMLO (Ct/Cs), thickness (h/L) and surface area of the skin (Sa/L2). Microinjection moulding technique was employed to fabricate PM. Histological studies revealed that the PM, owing to their geometry/design, formed wider and deeper microconduits when compared to ADM of similar length. Approximately 6.84- and 6.11-fold increase in the cumulative amount (48 h) of AMLO permeated was observed with 1.5 mm ADM and PM-3 treatments respectively, when compared to passive permeation amounts. Good correlations (R 2 > 0.89) were observed between different dimensionless parameters with scaling analyses. The enhancement in AMLO permeation was found to be in the order of 1.5 mm ADM ≥ PM-3 > 1.2 mm ADM > 0.6 mm ADM ≥PM-1 > passive. The study suggests that MN application enhances the AMLO transdermal permeation and the geometrical parameters of MNs play an important role in the degree of such enhancement.


Asunto(s)
Amlodipino/administración & dosificación , Antihipertensivos/administración & dosificación , Sistemas de Liberación de Medicamentos , Amlodipino/farmacocinética , Animales , Antihipertensivos/farmacocinética , Benzofenonas , Técnicas In Vitro , Cetonas , Microinyecciones , Agujas , Permeabilidad , Polietilenglicoles , Polímeros , Piel/metabolismo , Absorción Cutánea , Porcinos
15.
Pharmaceutics ; 7(4): 471-85, 2015 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-26529005

RESUMEN

Plasma technology has been widely used to increase the surface energy of the polymer surfaces for many industrial applications; in particular to increase in wettability. The present work was carried out to investigate how surface modification using plasma treatment modifies the surface energy of micro-injection moulded microneedles and its influence on drug delivery. Microneedles of polyether ether ketone and polycarbonate and have been manufactured using micro-injection moulding and samples from each production batch have been subsequently subjected to a range of plasma treatment. These samples were coated with bovine serum albumin to study the protein adsorption on these treated polymer surfaces. Sample surfaces structures, before and after treatment, were studied using atomic force microscope and surface energies have been obtained using contact angle measurement and calculated using the Owens-Wendt theory. Adsorption performance of bovine serum albumin and release kinetics for each sample set was assessed using a Franz diffusion cell. Results indicate that plasma treatment significantly increases the surface energy and roughness of the microneedles resulting in better adsorption and release of BSA.

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