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1.
Cureus ; 16(4): e58482, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38644943

RESUMO

INTRODUCTION: Gastric cancer (GC) is the third largest cause of cancer-related death worldwide, with major geographic disparities in incidence and outcomes. Sociodemographic indicators, food habits, and genetic predispositions all add to the load. Despite advances in systemic treatments, peritoneal metastasis remains a concern, with intraperitoneal chemotherapy (IPC) emerging as a promising treatment option. METHODS: A prospective cohort research was done, with 30 GC patients receiving cytoreductive surgery (CRS) followed by lobaplatin-based intraoperative chemotherapy. The study evaluated postoperative complications, survival rates, and disease recurrence using Statistical Package for the Social Sciences (SPSS) version 25.0 (IBM SPSS Statistics, Armonk, NY) for data analysis. The purpose of this study is to assess the effectiveness, safety, and dependability of lobaplatin as an intraoperative chemotherapeutic agent in patients having gastric cancer surgery, with a particular emphasis on those patients who do not have distant metastases. RESULTS: The study population had a balanced gender distribution, with an average age of 44.83 years. Most patients had advanced-stage cancer (T3 and T4), and lobaplatin treatment resulted in a low frequency of serious postoperative sequelae. Preliminary studies suggest that lobaplatin is a safe and potentially effective IPC drug for GC, with few side effects and adequate survival rates. CONCLUSION: Lobaplatin shows promise as an intraoperative chemotherapeutic treatment for gastric cancer, necessitating more research in bigger, randomized controlled studies to determine its efficacy and safety profile. The study emphasizes the need for novel treatment strategies to enhance the prognosis of GC patients, particularly those with peritoneal involvement.

2.
Cureus ; 16(4): e58481, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38644947

RESUMO

INTRODUCTION: Colorectal cancer (CRC) ranks as the second leading cause of cancer-related mortality among women and the third leading cause of cancer-associated mortality among men. Treatment of colon cancer is very crucial for a patient's survival. In this study, we assessed the reliability, efficacy, and safety of raltitrexed in intraoperative intraperitoneal chemotherapy for colon cancer. METHODOLOGY: A total of 57 patients with clinical stages II and III of colon cancer were included in the study. R0 resection surgery + hyperthermic intraperitoneal chemotherapy (HIPEC) procedure was done with raltitrexed. It was given in a dose of 3 mg/m2 in a 0.9% NS injection in a volume of 500 milliliters. Postoperative complications were observed. RESULT: The most common postoperative complication was nausea/vomiting, which was seen in 21 out of 57 patients (37%). The second most common complication was fever (18/57). None of the patients died or developed renal toxicity, hepatic toxicity, and intestinal obstruction. CONCLUSION: Raltitrexed is a reliable, efficient, and safe drug and can be used in intraoperative intraperitoneal chemotherapy of colon cancer.

3.
Eur J Hum Genet ; 31(11): 1270-1274, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37684519

RESUMO

Polydactyly is the most common limb malformation that occurs in 1.6-10.6 per one thousand live births, with incidence varying with ancestry. The underlying gene has been identified for many of the ~100 syndromes that include polydactyly. While for the more common form, nonsydromic polydactyly, eleven candidate genes have been reported. We investigated the underlying genetic cause of autosomal recessive nonsyndromic postaxial polydactyly in four consanguineous Pakistani families. Some family members with postaxial polydactyly also present with syndactyly, camptodactyly, or clinodactyly. Analysis of the exome sequence data revealed two novel homozygous frameshift deletions in EFCAB7: [c.830delG;p.(Gly277Valfs*5)]; in three families and [c.1350_1351delGA;p.(Asn451Phefs*2)] in one family. Sanger sequencing confirmed that these variants segregated with postaxial polydactyly, i.e., family members with postaxial polydactyly were found to be homozygous while unaffected members were heterozygous or wild type. EFCAB7 displays expressions in the skeletal muscle and on the cellular level in cilia. IQCE-EFCAB7 and EVC-EVC2 are part of the heterotetramer EvC complex, which is a positive regulator of the Hedgehog (Hh) pathway, that plays a key role in limb formation. Depletion of either EFCAB7 or IQCE inhibits induction of Gli1, a direct Hh target gene. Variants in IQCE and GLI1 have been shown to cause nonsyndromic postaxial polydactyly, while variants in EVC and EVC2 underlie Ellis van Creveld and Weyers syndromes, which include postaxial polydactyly as a phenotype. This is the first report of the involvement of EFCAB7 in human disease etiology.


Assuntos
Deformidades Congênitas dos Membros , Polidactilia , Humanos , Proteínas Hedgehog/metabolismo , Proteína GLI1 em Dedos de Zinco , Polidactilia/genética , Dedos/anormalidades
4.
Arthritis Rheumatol ; 75(8): 1434-1444, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36787101

RESUMO

OBJECTIVE: We undertook this study to explore the efficacy, safety, and tolerability of ziritaxestat, a selective autotaxin inhibitor, in patients with early diffuse cutaneous systemic sclerosis (dcSSc). METHODS: NOVESA was a 24-week, multicenter, phase IIa, double-blind, placebo-controlled study. Adults with dcSSc were randomized to oral ziritaxestat 600 mg once daily or matching placebo. The primary efficacy end point was change from baseline in modified Rodnan skin score (MRSS) at week 24. Secondary end points assessed safety and tolerability; other end points included assessment of skin and blood biomarkers. Patients in NOVESA could enter a 104-week open-label extension (OLE). RESULTS: Patients were randomized to ziritaxestat (n = 21) or placebo (n = 12). Reduction in MRSS was significantly greater in the ziritaxestat group versus the placebo group (-8.9 versus -6.0 units, respectively; P = 0.0411). Placebo patients switching to ziritaxestat in the OLE showed similar reductions in MRSS to those observed for ziritaxestat patients in the parent study. Ziritaxestat was well tolerated; the most frequent treatment-related treatment-emergent adverse events were headache and diarrhea. Circulating lysophosphatidic acid (LPA) C18:2 was significantly reduced, demonstrating ziritaxestat target engagement, and levels of fibrosis biomarkers were reduced in the blood. No differentially expressed genes were identified in skin biopsies. Significant changes in 109 genes were identified in blood samples. CONCLUSION: Ziritaxestat resulted in significantly greater reduction in MRSS at week 24 than placebo; no new safety signals emerged. Biomarker analysis suggests ziritaxestat may reduce fibrosis. Modulation of the autotaxin/LPA pathway could improve skin involvement in patients with dcSSc. A plain language summary is provided in the Supplementary Material, available on the Arthritis & Rheumatology website at https://onlinelibrary.wiley.com/doi/10.1002/art.42477.


Assuntos
Esclerodermia Difusa , Adulto , Humanos , Esclerodermia Difusa/patologia , Resultado do Tratamento , Pele/patologia , Biópsia , Método Duplo-Cego , Fibrose
5.
Trop Anim Health Prod ; 54(6): 369, 2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36323906

RESUMO

Castration is frequently used to reduce aggressive behavior and improve the meat quality of animals. Traditionally, surgical and mechanical castration are used to sterilize the animals, but these approaches are associated with a high level of pain, stress, long recovery periods, and post-operative infections. Immunocastration is a new animal-friendly, painless alternative castration technique that is used to prevent undesired sexual behavior, reduce aggressive behavior, prevent unwanted pregnancy, control wildlife populations and wandering species, enhance growth performance, improve meat quality, and treat various sex hormone-dependent disorders. The mechanism of immunocastration includes the immunological block of the hypothalamic-pituitary-gonadal axis (HPG axis) which inhibits gonadotropin secretions, causes atrophy of gonadal tissues, and inhibits gametogenesis, resulting in infertility in both female and male mammals. By the mid-1990s, various immunocastration vaccines have been tested in different animal models to achieve successful castration effects. Recently, genetic immunocastration especially DNA vaccine has gained increasing attention due to its safety, being animal-friendly, and being easy to use. This review aims to evaluate the potential of traditional castration methods, as well as the current status of immunocastration vaccines, their effects, and future prospective.


Assuntos
Bem-Estar do Animal , Vacinas , Masculino , Feminino , Animais , Orquiectomia/veterinária , Carne , Hormônio Liberador de Gonadotropina , Mamíferos
6.
Reprod Domest Anim ; 57(6): 653-664, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35247007

RESUMO

Immunocastration vaccines achieve their effects through neutralization of the endogenous hormone by the humoral antibody produced against the immunized genes, but there is little information regarding cell-mediated immune response on the gonadal function of the immunized model is available. In this study, we used ram as a model animal to identify the cellular immune response in testicular tissues of rams immunized with intranasal KISS1 gene vaccine. The immune castration model was evaluated by sexual behaviours, spermatogenesis and serum hormone profiles after the KISS1 gene immunization. Transcriptome analysis of testicular tissues was carried out to identify the expressions of protein-coding genes involved in cellular immunity. The results showed that we successfully constructed the KISS1 immune castration ram model, in which testicular growth and development, testosterone and kisspeptin-54 levels, and sexual function were suppressed in immunized rams (p < .05). Using Hiseq™ 2000 high sequencing for ram testicular, we identified 21 differentially expressed genes (DEGs) related to cellular immunity, of which, 14 genes were upregulated and seven genes were downregulated in the testis of the immunized group (p < .05). The Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment showed that these differentially expressed genes were enriched in the antigen presentation process mediated by MHC class I and the cytotoxic pathway mediated by natural killer cells. It is concluded that KISS1 gene vaccine induced the cell-mediated immune response in testicular tissue to suppress reproductive activities in rams.


Assuntos
Kisspeptinas , Vacinas , Animais , Imunidade Celular , Kisspeptinas/genética , Masculino , Orquiectomia/métodos , Orquiectomia/veterinária , Carneiro Doméstico , Testículo/fisiologia , Testosterona , Transcriptoma
7.
Pacing Clin Electrophysiol ; 45(5): 681-687, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35304920

RESUMO

As the established surgical mitral valve replacement (MVR) expands toward various contemporary techniques and access routes, the predictors and burden of procedure-related complications including the need for permanent pacemaker (PPM) implantation need to be identified. Digital databases were searched systematically to identify studies reporting the incidence of PPM implantation after MVR. Detailed study and patient-level baseline characteristics including the type of study, sample size, follow-up, number of post-MVR PPM implantations, age, gender, and baseline ECG abnormalities were abstracted. A total of 12 studies, recruiting 37,124 patients were included in the final analysis. Overall, 2820 (7.6%) patients required a PPM with the net rate ranging from 1.7% to 10.96%. Post-MVR atrioventricular (AV) block was the most commonly observed indication for PPM, followed by sinoatrial (SA) node dysfunction, and bradycardia. Age, male gender, pre-existing comorbid conditions, prior CABG, history of arrhythmias or using antiarrhythmic drugs, atrial fibrillation ablation, and double valve replacement were predictors of PPM implantation post-MVR. Age, male gender, comorbid conditions like diabetes and renal impairment, prior CABG, double valve replacement, and antiarrhythmic drugs served as positive predictors of PPM implantation in patients undergoing MVR.


Assuntos
Estenose da Valva Aórtica , Fibrilação Atrial , Bloqueio Atrioventricular , Marca-Passo Artificial , Substituição da Valva Aórtica Transcateter , Antiarrítmicos , Estenose da Valva Aórtica/cirurgia , Fibrilação Atrial/complicações , Fibrilação Atrial/cirurgia , Bloqueio Atrioventricular/terapia , Humanos , Masculino , Valva Mitral/cirurgia , Marca-Passo Artificial/efeitos adversos , Complicações Pós-Operatórias/cirurgia , Estudos Retrospectivos , Fatores de Risco , Síndrome do Nó Sinusal/complicações , Substituição da Valva Aórtica Transcateter/efeitos adversos , Resultado do Tratamento
8.
Saudi J Biol Sci ; 28(6): 3526-3533, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34121895

RESUMO

Virus is the most menacing factor for plant, which causes enormous economic losses in agriculture worldwide. Tobacco mosaic virus is most hazardous virus among the plants that can spread through biological and non-biological sources. TMV is ancient virus that causes huge economic losses to pepper cucumber ornamental crops and tobacco. It can be controlled by reducing the population of vector through pesticide application. However, the rapid usage of synthetic chemicals causes environmental pollution and destroys our ecosystem. Consequently, different approaches just like natural derivatives should be adopted for the environmental friendly management for TMV. This in vitro study demonstrated the potential role of natural metabolites such as poultry manure and plant extracts such as salicylic acid and citric acid for the control of TMV. Two different concentrations of poultry manure 60G and 30G were used. Poultry manure was mixed with the soil at the time of sowing. Disease severity was minimum at maximum concentration as compared to the control. Meanwhile, two different concentrations of salicylic acid and citric acid 60% and 90% were applied by foliar sprayer after three-leaf stages. Disease severity was observed after 5, 10, 15, 20, 25, and 30 days after disease inoculation. Here also maximum concentration showed the minimum disease severity and higher concentration of both animal and plants extracts were used for following experiment. Quantitative real-time PCR (RT-qPCR) results demonstrated that different plant defense-related genes such as PR1a, PAL, PR5, NPR1, PRIb, and PDF1.2 were up-regulated. Furthermore, applications of each treatment-induced systemic resistance against a wide range of pathogen including TMV and fungal pathogen Botrytis cinerea.

9.
Klin Padiatr ; 233(2): 53-58, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33339065

RESUMO

BACKGROUND: GLI3 is a transcriptional regulator of several genes involved in mammalian skeletal development. Mutations in the pleiotropic gene GLI3 may result in different inherited disorders including Greig cephalopolysyndactyly syndrome (GCPS). GCPS is characterized by mild to severe craniofacial and limb malformations. METHODS AND RESULTS: Here, we report clinical and molecular study of 3 families with GCPS originated in different regions of Pakistan. Sanger sequencing revealed two novel variants including a frameshift [c. 3790_3791InsC, p.(Gly1236Argfs*11)] and a missense [c.1692A>G, p.(His536Arg)], and one previously reported variant [c.1965_1966delAT, p.(His627Glufs*48)] located in 2 different domains of the GLI3. CONCLUSION: This study not only expanded spectrum of the mutations in the GLI3 but also highlighted phenotypic variability in the GCPS patients. This will facilitate diagnosis and genetic counseling of families with same and related disorders in the Pakistani population.


Assuntos
Fatores de Transcrição Kruppel-Like , Proteínas do Tecido Nervoso , Acrocefalossindactilia , Animais , Variação Biológica da População , Humanos , Fatores de Transcrição Kruppel-Like/genética , Proteínas do Tecido Nervoso/genética , Proteína Gli3 com Dedos de Zinco/genética
10.
J Inherit Metab Dis ; 43(4): 827-842, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31951021

RESUMO

Arginine:glycine amidinotransferase- and guanidinoacetate methyltransferase deficiency are severe neurodevelopmental disorders. It is not known whether mouse models of disease express a neuroanatomical phenotype. High-resolution magnetic resonance imaging (MRI) with advanced image analysis was performed in perfused, fixed mouse brains encapsulated with the skull from male, 10-12 week old Agat -exc and B6J.Cg-Gamt tm1Isb mice (n = 48; n = 8 per genotype, strain). T2-weighted MRI scans were nonlinearly aligned to a 3D atlas of the mouse brain with 62 structures identified. Local differences in brain shape related to genotype were assessed by analysis of deformation fields. Creatine (Cr) and guanidinoacetate (GAA) were measured with high-performance liquid chromatography (HPLC) in brain homogenates (n = 24; n = 4 per genotype, strain) after whole-body perfusion. Cr was decreased in the brain of Agat- and Gamt mutant mice. GAA was decreased in Agat-/- and increased in Gamt-/- . Body weight and brain volume were lower in Agat-/- than in Gamt-/- . The analysis of entire brain structures revealed corpus callosum, internal capsule, fimbria and hypothalamus being different between the genotypes in both strains. Eighteen and fourteen significant peaks (local areas of difference in relative size) were found in Agat- and Gamt mutants, respectively. Comparing Agat-/- with Gamt-/- , we found changes in three brain regions, lateral septum, amygdala, and medulla. Intra-strain differences in four brain structures can be associated with Cr deficiency, while the inter-strain differences in three brain structures of the mutant mice may relate to GAA. Correlating these neuroanatomical findings with gene expression data implies the role of Cr metabolism in the developing brain and the importance of early intervention in patients with Cr deficiency syndromes.


Assuntos
Encéfalo/metabolismo , Encéfalo/patologia , Creatina/metabolismo , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Glicina/análogos & derivados , Guanidinoacetato N-Metiltransferase/genética , Proteínas Supressoras de Tumor/genética , Animais , Arginina/metabolismo , Encéfalo/diagnóstico por imagem , Cromatografia Líquida de Alta Pressão , Metilases de Modificação do DNA/deficiência , Enzimas Reparadoras do DNA/deficiência , Glicina/metabolismo , Guanidinoacetato N-Metiltransferase/deficiência , Imageamento por Ressonância Magnética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fenótipo , Proteínas Supressoras de Tumor/deficiência
11.
Environ Sci Pollut Res Int ; 27(3): 3076-3085, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31838694

RESUMO

This study evaluated the effect of wood extracts from Tectona grandis, Dalbergia sissoo, Cedrus deodara, and Pinus roxburghii combined with linseed oil as protectants of two non-durable wood species against the termite, Heterotermes indicola. Heartwood blocks (19 × 19 × 19 mm) and wood shavings were extracted using an ethanol/toluene (2:1) solvent system. Results of choice and no-choice tests with solvent-extracted and non-extracted heartwood blocks showed greater wood mass loss from termite feeding on solvent-extracted blocks compared with non-extracted blocks for all wood species. Significantly higher termite mortality was observed after termite exposure to non-extracted blocks compared with extracted blocks for all durable species. Sapwood blocks of two non-durable wood species (southern pine and cottonwood) were vacuum/pressure impregnated separately with each of the four types of extract at a concentration of 7.5 mg ml-1, linseed oil (20%) and a mixture of oil (20%) and extracts (4.25 mg ml-1) for the laboratory and field tests. Results showed that extract-oil mixture imparted significantly higher termite resistance compared with linseed or extracts alone under laboratory conditions. This apparent synergistic effect was clearly noted when linseed oil was combined with extracts from T. grandis or D. sissoo followed by an extract-oil mixture using C. deodara. These extract oil mixtures showed significantly less weight loss for the treated non-durable wood species and higher termite mortality (83-100%) compared with the control treatments and other extract-linseed oil mixtures tested. Treatment of both non-durable wood species with T. grandis + oil and D. sissoo + oil prevented termite damage compared with other treatments when blocks and stakes were exposed in the field for a period of 2 years. Results of the current study indicated that a mixture of a particular heartwood extract with linseed oil has potential to be used as environmentally friendly wood protectants.


Assuntos
Isópteros , Óleo de Semente do Linho , Extratos Vegetais/toxicidade , Madeira , Animais , Baratas , Sinergismo Farmacológico
12.
Rev. bras. entomol ; 64(1): e201968, 2020. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1101566

RESUMO

ABSTRACT The house fly, Musca domestica L. (Diptera: Muscidae), is a major pest of all aspects of life, like the domestic, medical and veterinary and causal agent of several pathogenic diseases. The present study was conducted to evaluate the potential of different insecticide-free baits against house fly by incorporating flower methanol extract of Helianthus annuus (sunflower) and Tegetes erecta (marigold) at 10%, 20% and 30% bait formulation of corn syrup, dried milk and water. However, imidacloprid and thiacloprid (each at 5% concentration) were also included in the study for comparison. Results showed that insecticide baits were superior in causing mortality of adult house fly but dependent upon syrup. Overall, 20% baits of both extracts caused more than half population death of house fly within 48h. On the other hand, the mortality rate by 30% baits (from sunflower and marigold) had a similar impact as observed in case of imidacloprid and thiacloprid baits. Therefore, biological baits could play a more active and safer role in the management of house fly as compared to synthetic insecticides.

13.
Rev. bras. entomol ; 64(1): e201998, 2020. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1057800

RESUMO

Abstract Synthetic wood preservatives are the causes of large-scale environmental pollution and few have been withdrawn from the commercial markets in the past years. The present studies focused on determination of naturally present extractives of Ziziphus mauritiana as less toxic wood protectant against subterranean termites. Firstly, natural resistance of Z. mauritiana heartwood against termite was determined by exposing stakes in the field. For the preparation of extractives, air-dried Z. mauritiana heartwood and bark shavings were soaked in 1 liter each of ethyl acetate, hexane, petroleum ether and water in a bottle separately. Different dipping treatment times (36 and 72 hours) at 10, 20 and 30% concentrations of extractives on Populus deltoides wooden stakes were used and stakes were exposed to termites in submerged manner. Combination of extractives in different solvents were included as separate experiment and finally, seasoning prior to extractives application on P. deltoides wooden stakes was also done and stakes were arranged in three replications for each treatment. Maximum mean percent weight loss (81.1%) was observed in case of P. deltoides followed by boiled Z. mauritiana (15.24%) in termite resistance test. Stakes treated with petroleum ether extracts had minimum weight loss alone or in combination with other extract's solvent in all experiments. Extractives in other solvents followed petroleum ether non-significantly but were significantly different from their respective control treatment, which had the highest weight loss (>60%). Transferring durability using extracts of Z. mauritiana increased resistance of non-durable P. deltoides against termites and extractives could be used as wood preservatives.

14.
Sci Rep ; 9(1): 16262, 2019 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-31700161

RESUMO

Orf is a highly contagious zoonotic disease of small ruminants caused by Parapoxvirus. Kisspeptin, encoded by the KISS1 gene with its cognate receptor GPR-54 is recognized as an upstream orchestrator in the hypothalamic-pituitary-gonadal axis. This study was designed to construct a DNA vaccine that produces a fused peptide composed of a major immunodominant protein of the orf virus (B2L) and kisspeptin-54, a neuropeptide with recognized roles in mammalian reproductive biology. The administration of this recombinant vaccine is shown to produce a significant antibody and cell-mediated immune response directed against B2L compared to the control group (p < 0.05). Furthermore, we found that rats inoculated with PBK-asd vaccine up-regulated antigen-mediated splenocyte proliferation and significantly raised antigen-specific tumor necrosis factor-alpha (TNFα-), interferon-gamma (IFN-ϒ) and interleukin (IL-2) compared to the control group (p < 0.05). This recombinant vaccine also stimulated antibody responses to kisspeptin and decreased serum luteinizing hormone and testosterone levels. Moreover, the current recombinant vaccine caused testicular atrophy and arrested spermatogenesis. It is concluded that this recombinant B2L and Kisspeptin-54 vaccine could be a promising approach for construction of bivalent orf virus and immunocastration vaccine. Furthermore, we concluded that the orf virus envelope protein (B2L) could be used as an immunomodulator for kisspeptin-54 to produce a strong antibody response.


Assuntos
Ectima Contagioso/imunologia , Kisspeptinas/imunologia , Vírus do Orf/imunologia , Espermatogênese/imunologia , Vacinas de DNA/imunologia , Proteínas Virais/imunologia , Animais , Biomarcadores , Citocinas/metabolismo , Ectima Contagioso/virologia , Hormônios , Imunofenotipagem , Masculino , Ratos , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Testículo/imunologia , Testículo/metabolismo , Vacinas de DNA/administração & dosagem
15.
Sci Rep ; 9(1): 2524, 2019 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-30792430

RESUMO

Superresolution microscopy offers the advantage of imaging biological structures within cells at the nano-scale. Here we apply two superresolution microscopy techniques, specifically 3D structured illumination microscopy (3D-SIM) and direct stochastic optical reconstruction microscopy (dSTORM), a type of single molecule localisation microscopy, to localise IRSp53 protein and its I-BAR domain in relation to F-actin within filopodia. IRSp53 generates dynamic (extending and retracting) filopodia 300 nm wide with a distinct gap between IRSp53 and F-actin. By contrast, protrusions induced by the I-BAR domain alone are non-dynamic measuring between 100-200 nm in width and exhibit a comparatively closer localisation of the I-BAR domain with the F-actin. The data suggest that IRSp53 membrane localisation is spatially segregated to the lateral edges of filopodia, in contrast to the I-BAR domain is uniformly distributed throughout the membranes of protrusions. Modeling of fluorescence recovery after photobleaching (FRAP) data suggests that a greater proportion of I-BAR domain is associated with membranes when compared to full length IRSp53. The significance of this new data relates to the role filopodia play in cell migration and its importance to cancer.


Assuntos
Actinas/genética , Membrana Celular/ultraestrutura , Proteínas do Tecido Nervoso/ultraestrutura , Imagem Individual de Molécula/métodos , Actinas/ultraestrutura , Animais , Membrana Celular/genética , Movimento Celular/genética , Recuperação de Fluorescência Após Fotodegradação/métodos , Humanos , Camundongos , Neoplasias/genética , Neoplasias/patologia , Proteínas do Tecido Nervoso/genética , Ligação Proteica/genética , Domínios Proteicos/genética
16.
Protein Pept Lett ; 25(7): 677-687, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29921198

RESUMO

BACKGROUND: Thrombus is composed of two main substances i.e. red blood cells and aggregated platelets which make a web of inter-connected fibrin proteins. During injury it prevents bleeding, so it is very useful but it can be very dangerous if it is produced in healthy blood vessels and block the blood flow through it. Mural thrombi attaches with the blood vessels but in most cases do not block it completely. Venoms are an incredible source of peptides having amazing bioactivities with varying number of amino acid residues. Anticoagulant venom peptides however inhibit the enzyme taking part in coagulation like factor Xa and thrombin. The anticoagulant potential of venom peptides have also been reported by the degradation of the fibrin or fibrinogen related to serine or metalloproteases. Designing and development of numerous therapeutic agents or lead molecules mostly for cardiovascular diseases have been motivated from toxins/proteins from snake venoms. For example, disintegrins, a large family of platelet aggregation inhibitors found in viperid and crotalid snake venoms were the basis for designing of platelet aggregation inhibitors such as eptifibatide and tirofiban. CONCLUSION: Ancrod isolated from Malayan pit viper venom can cause reduction in level of blood fibrinogen and has been effectively tried in various ischemic conditions, including stroke. In order to search for novel lead molecules, the emphasis should be on isolation and characterization of pharmacologically active snake venoms proteins affecting blood coagulation and platelet aggregation. In this review an attempt has been made to recapitulates and discuss venoms of different animals and arthropod having anticoagulant peptides for their potential use in therapeutics and diagnostics.


Assuntos
Fibrinolíticos , Peptídeos , Venenos de Serpentes , Trombose Venosa/tratamento farmacológico , Animais , Humanos , Serpentes
17.
Curr Biol ; 26(19): 2651-2658, 2016 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-27641764

RESUMO

The nuclear lamina is a universal feature of metazoan nuclear envelopes (NEs) [1]. In mammalian cells, it appears as a 10-30 nm filamentous layer at the nuclear face of the inner nuclear membrane (INM) and is composed primarily of A- and B-type lamins, members of the intermediate filament family [2]. While providing structural integrity to the NE, the lamina also represents an important signaling and regulatory platform [3]. Two A-type lamin isoforms, lamins A and C (LaA and LaC), are expressed in most adult human cells. Encoded by a single gene, these proteins are largely identical, diverging only in their C-terminal tail domains. By contrast with that of LaC, the unique LaA tail undergoes extensive processing, including farnesylation and endo-proteolysis [4, 5]. However, functional differences between LaA and LaC are still unclear. Compounding this uncertainty, the structure of the lamina remains ill defined. In this study, we used BioID, an in vivo proximity-labeling method to identify differential interactors of A-type lamins [6]. One of these, Tpr, a nuclear pore complex (NPC) protein, is highlighted by its selective association with LaC. By employing superresolution microscopy, we demonstrate that this Tpr association is mirrored in enhanced interaction of LaC with NPCs. Further superresolution studies visualizing both endogenous A- and B-type lamins have allowed us to construct a nanometer-scale model of the mammalian nuclear lamina. Our data indicate that different A- and B-type lamin species assemble into separate filament networks that together form an extended composite structure at the nuclear periphery providing attachment sites for NPCs, thereby regulating their distribution.


Assuntos
Filamentos Intermediários/metabolismo , Lamina Tipo A/metabolismo , Poro Nuclear/fisiologia , Humanos , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Proteínas Proto-Oncogênicas/metabolismo
18.
J Cell Sci ; 129(14): 2829-40, 2016 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-27278019

RESUMO

Rif induces dorsal filopodia but the signaling pathway responsible for this has not been identified. We show here that Rif interacts with the I-BAR family protein IRTKS (also known as BAIAP2L1) through its I-BAR domain. Rif also interacts with Pinkbar (also known as BAIAP2L2) in N1E-115 mouse neuroblastoma cells. IRTKS and Rif induce dorsal membrane ruffles and filopodia. Dominant-negative Rif inhibits the formation of IRTKS-induced morphological structures, and Rif activity is blocked in IRTKS-knockout (KO) cells. To further define the Rif-IRTKS signaling pathway, we identify Eps8 and WAVE2 (also known as WASF2) as IRTKS interactors. We find that Eps8 regulates the size and number of dorsal filopodia and membrane ruffles downstream of Rif-IRTKS signaling, whereas WAVE2 modulates dorsal membrane ruffling. Furthermore, our data suggests that Tir, a protein essential for enterohemorrhagic Escherichia coli infection, might compete for Rif for interaction with the I-BAR domain of IRTKS. Based on this evidence, we propose a model in which Rho family GTPases use the I-BAR proteins, IRSp53 (also known as BAIAP2), IRTKS and Pinkbar, as a central mechanism to modulate cell morphology.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , GTP Fosfo-Hidrolases/metabolismo , Proteínas dos Microfilamentos/metabolismo , Pseudópodes/metabolismo , Transdução de Sinais , Família de Proteínas da Síndrome de Wiskott-Aldrich/metabolismo , Animais , Células HeLa , Humanos , Camundongos , Modelos Biológicos , Células NIH 3T3 , Ligação Proteica
19.
Chempluschem ; 81(1): 100-107, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31968740

RESUMO

A facile method for the synthesis of highly fluorescent manganese-doped zinc sulfide (ZnS:Mn) nanocrystals covalently functionalized with polyethylene glycol conjugated graphene oxide (GO-PEG) for drug delivery and cell labeling is reported. First, covalently functionalized GO with PEG-bis(amine) to enhance the solubility and biocompatibility in water and physiological buffers. Second, glutathione (GSH)-coated ZnS:Mn-doped nanocrystals were covalently grafted onto GO-PEG. An acid-amidation process was employed to obtain GO-PEG/ZnS:Mn nanocomposites, which were characterized by UV/Vis, photoluminescence, and Fourier transform infrared spectroscopies, and transmission electron microscopy. Finally, the anticancer drug doxorubicin (DOX) was noncovalently loaded onto these GO-PEG/ZnS:Mn composite particles. High drug entrapment efficiency (100 % due to more GO surface available for binding), slow in vitro release of drug (ca. 40 % at acidic pH), better HeLa cancer cell killing efficiency (ca. 85 %), and cell labeling capability are the important traits of these DOX-loaded nanocomposites. It is believed these novel fluorescent [GO-PEG/ZnS:Mn]-DOX composite particles have great potential as theranostic agents in cancer diagnosis and therapy.

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