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1.
Eur J Orthop Surg Traumatol ; 34(1): 471-478, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37612566

RESUMO

PURPOSE: The aim of this study was to evaluate the results of distal femoral fracture fixation of two different methods, lateral locking plate (LP) or an Intra-medullary nail (IMN), in patients managed in our institution. More specifically, to assess: (a) if there was a difference in functional outcomes between the LP and IMN groups; (b) whether the rate of complications was different between the two groups. METHODS: Between January 2009 and December 2018 adult patients with distal femoral fractures managed in our unit with either LP or IMN for extra and intra-articular fractures were eligible to participate. Demographic details, fracture type, procedures performed, time to union, complications and functional scores (Oxford Knee Score) were recorded and analysed. The mean follow up was 4 years (12-120 months). RESULTS: Out of 193 patients who met the inclusion criteria, 93 received an IMN whereas 100 patients were treated with LP. Mean age was 64.2 (18-99) and 70.1 (18-100) for the IMN and LP groups respectively. Overall, the two groups had similar demographics and there was no significant difference in the type of fractures sustained (p > 0.05). The Oxford Knee Score was highest for patients fixed with LP, mean 37.3 (6-48, SD 7.3) versus 28.4 (3-48, SD 14.4), (p = < 0.02) compared to the IMN group. In terms of complications, the rate of non-union was higher in the LP group 8.6% versus 4% in those patients treated with an IMN, p value < 0.01. CONCLUSION: While the rate of non-union was higher in the LP group and the functional results were superior in the plating group.


Assuntos
Fraturas Femorais Distais , Fraturas do Fêmur , Fixação Intramedular de Fraturas , Adulto , Humanos , Pessoa de Meia-Idade , Fixação Intramedular de Fraturas/efeitos adversos , Fixação Intramedular de Fraturas/métodos , Estudos Retrospectivos , Consolidação da Fratura , Resultado do Tratamento , Placas Ósseas/efeitos adversos , Fraturas do Fêmur/etiologia , Pinos Ortopédicos/efeitos adversos
2.
Arch Razi Inst ; 78(2): 689-699, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37396746

RESUMO

The presence and characteristics of HMTV in Iraqi breast cancer women are still unknown. Furthermore, the identification of HMTV in human breast carcinoma tissue of patients differs by country, and the factors that influence it are still unknown. In many epithelial tumor types, the EGFR and its signaling pathways outcomes are necessary for the behavior of cells and regulating their proliferation, and it has been discovered that DAXX has strong carcinogenic characteristics and could be a new treatment target. This case-control retrospective study investigated the presence of HMTV in paraffin-embedded blocks (FFPT) of tumor samples from 60 Iraqi women patients diagnosed with primary breast cancer and 20 cases of benign tumors as a control group. HMTV env sequences were identified by Real-time PCR. EGFR and DAXX expression were immun0-detected by the immuno-histochemistry technique. HMTV sequences were detected in 15 (25%) samples of malignant breast tumors and 8 (40%) samples of benign breast tumors. There was no statistically significant association between the detection of env sequences of HMTV and age, grade, hormone receptors, EGFR, or DAXX expression compared to clinicopathological characteristics. However, statistically, the data showed a highly significant difference in the Expression of EGFR between study groups, age, and histological types (P=0.0001), and a significant negative association was observed between EGFR and both Her2 and TNBC. There was a statistically significant difference between DAXX (+) and DAXX (-) in study groups (P=0.002), and it was significantly associated with age and histological types of breast cancer (P=0.031 and 0.007, respectively). No significant association was found between DAXX and EGFR, grade, Her2. TNBC of breast cancer. The current study found HMTV env sequences in breast tumors of Iraqi women, suggesting that a larger sample size is needed to illustrate the potential causative role of HMTV in the development of human breast malignancy. Moreover, a negative association was found between HMTV and DAXX and EGFR Expression.


Assuntos
Betaretrovirus , Neoplasias de Mama Triplo Negativas , Humanos , Feminino , Estudos Retrospectivos , Imuno-Histoquímica , Estudos de Casos e Controles , Chaperonas Moleculares , Proteínas Correpressoras , Receptores ErbB
3.
Toxins (Basel) ; 15(4)2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-37104203

RESUMO

Snakebite envenoming is a neglected tropical disease prevalent in South Asia. In Pakistan, antivenoms are commonly imported from India despite the controversy over their effectiveness. To solve the problem, the locals have developed the Pakistani Viper Antivenom (PVAV), raised against Sochurek's Saw-scaled Viper (Echis carinatus sochureki) and Russell's Viper (Daboia russelii) of Pakistani origin. This study is set to evaluate the composition purity, immuno-specificity and neutralization efficacy of PVAV. Chromatographic and electrophoretic profiling coupled with proteomic mass spectrometry analysis showed PVAV containing high-purity immunoglobulin G with minimum impurities, notably the absence of serum albumin. PVAV is highly immuno-specific toward the venoms of the two vipers and Echis carinatus multisquamatus, which are indigenous to Pakistan. Its immunoreactivity, however, reduces toward the venoms of other Echis carinatus subspecies and D. russelii from South India as well as Sri Lanka. Meanwhile, its non-specific binding activities for the venoms of Hump-nosed Pit Vipers, Indian Cobras and kraits were extremely low. In the neutralization study, PVAV effectively mitigated the hemotoxic and lethal effects of the Pakistani viper venoms, tested in vitro and in vivo. Together, the findings suggest the potential utility of PVAV as a new domestic antivenom for the treatment of viperid envenoming in Pakistan.


Assuntos
Daboia , Mordeduras de Serpentes , Viperidae , Animais , Antivenenos/farmacologia , Paquistão , Proteômica , Mordeduras de Serpentes/tratamento farmacológico , Venenos de Víboras/toxicidade
4.
Semin Cancer Biol ; 83: 77-87, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-33486076

RESUMO

Despite the advances in treatment using chemotherapy or targeted therapies, due to static survival rates, non-small cell lung cancer (NSCLC) is the major cause of cancer-related deaths worldwide. Epigenetic-based therapies have been developed for NSCLC by targeting DNA methyltransferases (DNMTs) and histone-modifying enzymes. However, treatment using single epigenetic agents on solid tumours has been inadequate; whereas, treatment with a combination of DNMTs inhibitors with chemotherapy and immunotherapy has shown great promise. Dietary sources of phytochemicals could also inhibit DNMTs and cancer stem cells, representing a novel and promising way to prevent and treat cancer. Herein, we will discuss the different DNMTs, DNA methylation profiling in NSCLC as well as current demethylating agents in ongoing clinical trials. Therefore, providing a concise overview of future developments in the field of epigenetic therapy in NSCLC.


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , DNA , Metilação de DNA , Metilases de Modificação do DNA/genética , Epigênese Genética , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética
5.
Genomics ; 113(6): 3476-3486, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34391867

RESUMO

How stable and temperature-dependent variations in DNA methylation and nucleosome occupancy influence alternative splicing (AS) remains poorly understood in plants. To answer this, we generated transcriptome, whole-genome bisulfite, and MNase sequencing data for an epigenetic Recombinant Inbred Line (epiRIL) of A. thaliana at normal and cold temperature. For comparative analysis, the same data sets for the parental ecotype Columbia (Col-0) were also generated, whereas for DNA methylation, previously published high confidence methylation profiles of Col-0 were used. Significant epigenetic differences in an identical genetic background were observed between Col-0 and epiRIL lines under normal and cold temperatures. Our transcriptome data revealed that differential DNA methylation and nucleosome occupancy modulate expression levels of many genes and AS in response to cold. Collectively, DNA methylation and nucleosome levels exhibit characteristic patterns around intron-exon boundaries at normal and cold conditions, and any perturbation in them, in an identical genetic background is sufficient to modulate AS in Arabidopsis.


Assuntos
Arabidopsis , Processamento Alternativo , Arabidopsis/genética , Metilação de DNA , Epigênese Genética , Patrimônio Genético
6.
New Phytol ; 229(4): 1937-1945, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33135169

RESUMO

Alternative splicing (AS) is a major gene regulatory mechanism in plants. Recent evidence supports co-transcriptional splicing in plants, hence the chromatin state can impact AS. However, how dynamic changes in the chromatin state such as nucleosome occupancy influence the cold-induced AS remains poorly understood. Here, we generated transcriptome (RNA-Seq) and nucleosome positioning (MNase-Seq) data for Arabidopsis thaliana to understand how nucleosome positioning modulates cold-induced AS. Our results show that characteristic nucleosome occupancy levels are strongly associated with the type and abundance of various AS events under normal and cold temperature conditions in Arabidopsis. Intriguingly, exitrons, alternatively spliced internal regions of protein-coding exons, exhibit distinctive nucleosome positioning pattern compared to other alternatively spliced regions. Likewise, nucleosome patterns differ between exitrons and retained introns, pointing to their distinct regulation. Collectively, our data show that characteristic changes in nucleosome positioning modulate AS in plants in response to cold.


Assuntos
Arabidopsis , Processamento Alternativo/genética , Arabidopsis/genética , Cromatina , Íntrons , Nucleossomos
7.
Biochem Soc Trans ; 48(6): 2399-2414, 2020 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-33196096

RESUMO

Next-generation sequencing (NGS) technologies - Illumina RNA-seq, Pacific Biosciences isoform sequencing (PacBio Iso-seq), and Oxford Nanopore direct RNA sequencing (DRS) - have revealed the complexity of plant transcriptomes and their regulation at the co-/post-transcriptional level. Global analysis of mature mRNAs, transcripts from nuclear run-on assays, and nascent chromatin-bound mRNAs using short as well as full-length and single-molecule DRS reads have uncovered potential roles of different forms of RNA polymerase II during the transcription process, and the extent of co-transcriptional pre-mRNA splicing and polyadenylation. These tools have also allowed mapping of transcriptome-wide start sites in cap-containing RNAs, poly(A) site choice, poly(A) tail length, and RNA base modifications. The emerging theme from recent studies is that reprogramming of gene expression in response to developmental cues and stresses at the co-/post-transcriptional level likely plays a crucial role in eliciting appropriate responses for optimal growth and plant survival under adverse conditions. Although the mechanisms by which developmental cues and different stresses regulate co-/post-transcriptional splicing are largely unknown, a few recent studies indicate that the external cues target spliceosomal and splicing regulatory proteins to modulate alternative splicing. In this review, we provide an overview of recent discoveries on the dynamics and complexities of plant transcriptomes, mechanistic insights into splicing regulation, and discuss critical gaps in co-/post-transcriptional research that need to be addressed using diverse genomic and biochemical approaches.


Assuntos
Proteínas de Plantas/metabolismo , Transcriptoma , Processamento Alternativo , Arabidopsis/genética , Sequência de Bases , Cromatina/química , Cromatina/metabolismo , Perfilação da Expressão Gênica , Genes de Plantas , Proteínas de Fluorescência Verde/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Isoformas de Proteínas , Processamento Pós-Transcricional do RNA , Splicing de RNA , RNA-Seq , Análise de Sequência de RNA
8.
Sci Rep ; 10(1): 11261, 2020 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-32647261

RESUMO

Snakebite envenomation is a neglected tropical disease of high mortality and morbidity largely due to insufficient supply of effective and affordable antivenoms. Snake antivenoms are mostly effective against the venoms used in their production. It is thus crucial that effective and affordable antivenom(s) with wide para-specificity, capable of neutralizing the venoms of a large number of snakes, be produced. Here we studied the pan-specific antiserum prepared previously by a novel immunization strategy involving the exposure of horses to a 'diverse toxin repertoire' consisting of 12 neurotoxic Asian snake toxin fractions/ venoms from six species. This antiserum was previously shown to exhibit wide para-specificity by neutralizing 11 homologous and 16 heterologous venoms from Asia and Africa. We now show that the antiserum can neutralize 9 out of 10 additional neurotoxic venoms. Altogether, 36 snake venoms belonging to 10 genera from 4 continents were neutralized by the antiserum. Toxin profiles previously generated using proteomic techniques of these 36 venoms identified α-neurotoxins, ß-neurotoxins, and cytotoxins as predominant toxins presumably neutralized by the antiserum. The bases for the wide para-specificity of the antiserum are discussed. These findings indicate that it is feasible to generate antivenoms of wide para-specificity against elapid neurotoxic venoms from different regions in the world and raises the possibility of a universal neurotoxic antivenom. This should reduce the mortality resulting from neurotoxic snakebite envenomation.


Assuntos
Antivenenos/química , Venenos Elapídicos/química , Imunização , Neurotoxinas/química , Animais , Elapidae , Soros Imunes , Proteômica , Venenos de Serpentes , Serpentes , Vacinação
9.
Front Plant Sci ; 10: 1160, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31632417

RESUMO

Alternative splicing (AS) of pre-mRNAs contributes to transcriptome diversity and enables plants to generate different protein isoforms from a single gene and/or fine-tune gene expression during different development stages and environmental changes. Although AS is pervasive, the genetic basis for differential isoform usage in plants is still emerging. In this study, we performed genome-wide analysis in 666 geographically distributed diverse ecotypes of Arabidopsis thaliana to identify genomic regions [splicing quantitative trait loci (sQTLs)] that may regulate differential AS. These ecotypes belong to different microclimatic conditions and are part of the relict and non-relict populations. Although sQTLs were spread across the genome, we observed enrichment for trans-sQTL (trans-sQTLs hotspots) on chromosome one. Furthermore, we identified several sQTL (911) that co-localized with trait-linked single nucleotide polymorphisms (SNP) identified in the Arabidopsis genome-wide association studies (AraGWAS). Many sQTLs were enriched among circadian clock, flowering, and stress-responsive genes, suggesting a role for differential isoform usage in regulating these important processes in diverse ecotypes of Arabidopsis. In conclusion, the current study provides a deep insight into SNPs affecting isoform ratios/genes and facilitates a better mechanistic understanding of trait-associated SNPs in GWAS studies. To the best of our knowledge, this is the first report of sQTL analysis in a large set of Arabidopsis ecotypes and can be used as a reference to perform sQTL analysis in the Brassicaceae family. Since whole genome and transcriptome datasets are available for these diverse ecotypes, it could serve as a powerful resource for the biological interpretation of trait-associated loci, splice isoform ratios, and their phenotypic consequences to help produce more resilient and high yield crop varieties.

10.
Front Plant Sci ; 10: 708, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31244866

RESUMO

Plants, unlike animals, exhibit a very high degree of plasticity in their growth and development and employ diverse strategies to cope with the variations during diurnal cycles and stressful conditions. Plants and animals, despite their remarkable morphological and physiological differences, share many basic cellular processes and regulatory mechanisms. Alternative splicing (AS) is one such gene regulatory mechanism that modulates gene expression in multiple ways. It is now well established that AS is prevalent in all multicellular eukaryotes including plants and humans. Emerging evidence indicates that in plants, as in animals, transcription and splicing are coupled. Here, we reviewed recent evidence in support of co-transcriptional splicing in plants and highlighted similarities and differences between plants and humans. An unsettled question in the field of AS is the extent to which splice isoforms contribute to protein diversity. To take a critical look at this question, we presented a comprehensive summary of the current status of research in this area in both plants and humans, discussed limitations with the currently used approaches and suggested improvements to current methods and alternative approaches. We end with a discussion on the potential role of epigenetic modifications and chromatin state in splicing memory in plants primed with stresses.

11.
Trends Plant Sci ; 24(6): 496-506, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30852095

RESUMO

Alternative splicing (AS) generates multiple transcripts from the same gene, however, AS contribution to proteome complexity remains elusive in plants. AS is prevalent under stress conditions in plants, but it is counterintuitive why plants would invest in protein synthesis under declining energy supply. We propose that plants employ AS not only to potentially increasing proteomic complexity, but also to buffer against the stress-responsive transcriptome to reduce the metabolic cost of translating all AS transcripts. To maximise efficiency under stress, plants may make fewer proteins with disordered domains via AS to diversify substrate specificity and maintain sufficient regulatory capacity. Furthermore, we suggest that chromatin state-dependent AS engenders short/long-term stress memory to mediate reproducible transcriptional response in the future.


Assuntos
Processamento Alternativo , Proteoma , Regulação da Expressão Gênica de Plantas , Proteômica , Estresse Fisiológico
12.
Med Vet Entomol ; 33(3): 336-344, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30779201

RESUMO

Anopheles subpictus s.l. Grassi (Diptera: Culicidae) is a malaria vector in South Asia, where insecticides are the mainstay for vector control interventions. Information on any variation in metabolic enzyme levels in mosquitoes is helpful with respect to adapting alternative strategies for vector control. The scarce data on the biochemical basis of insecticide resistance in malaria vectors of Pakistan limit the available information for vector control interventions within the country. The insecticide susceptibility status and its biochemical basis against dichlorodiphenyltrichloroethane (DDT) (4%), deltamethrin (0.05%) and permethrin (0.75%) in An. subpictus s.l. collected from all Tehsils of district Kasur were evaluated. For this purpose, a World Health Organization susceptibility bioassay was performed followed by the detection of altered metabolic enzyme activity using biochemical assays. Similarly, a significant difference in knock-down effect was observed among field collected and susceptible strain against all insecticides 24 h post exposure. The overall mean mortality rates of DDT, deltamethrin and permethrin were 27.86% [95% confidence interval (CI) = 29.65-26.06], 44.89% (95% CI = 46.23-43.54) and 78.82% (95% CI = 80.16-77.47), respectively. The biochemical assays revealed an elevated level of metabolic enzymes in the field population. The results provide evidence of resistance against organochlorine and pyrethroid groups in a field population of An. subpictus s.l. from district Kasur mediated by multiple metabolic mechanisms, including acetylcholinesterases, esterases, cytochrome P450 and glutathione S-transferases.


Assuntos
Anopheles/efeitos dos fármacos , DDT/farmacologia , Resistência a Inseticidas , Inseticidas/farmacologia , Mosquitos Vetores/efeitos dos fármacos , Piretrinas/farmacologia , Animais , Anopheles/metabolismo , Feminino , Inativação Metabólica , Malária/transmissão , Mosquitos Vetores/metabolismo , Paquistão , Plasmodium/fisiologia
13.
Nucleic Acids Res ; 47(6): 2716-2726, 2019 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-30793202

RESUMO

Plants display exquisite control over gene expression to elicit appropriate responses under normal and stress conditions. Alternative splicing (AS) of pre-mRNAs, a process that generates two or more transcripts from multi-exon genes, adds another layer of regulation to fine-tune condition-specific gene expression in animals and plants. However, exactly how plants control splice isoform ratios and the timing of this regulation in response to environmental signals remains elusive. In mammals, recent evidence indicate that epigenetic and epitranscriptome changes, such as DNA methylation, chromatin modifications and RNA methylation, regulate RNA polymerase II processivity, co-transcriptional splicing, and stability and translation efficiency of splice isoforms. In plants, the role of epigenetic modifications in regulating transcription rate and mRNA abundance under stress is beginning to emerge. However, the mechanisms by which epigenetic and epitranscriptomic modifications regulate AS and translation efficiency require further research. Dynamic changes in the chromatin landscape in response to stress may provide a scaffold around which gene expression, AS and translation are orchestrated. Finally, we discuss CRISPR/Cas-based strategies for engineering chromatin architecture to manipulate AS patterns (or splice isoforms levels) to obtain insight into the epigenetic regulation of AS.


Assuntos
Processamento Alternativo/genética , Regulação da Expressão Gênica de Plantas , Estresse Fisiológico/genética , Animais , Arabidopsis/genética , Metilação de DNA/genética , Epigênese Genética/fisiologia , Redes Reguladoras de Genes/genética , Humanos , Transcrição Gênica/genética
14.
J Proteomics ; 193: 243-254, 2019 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-30385415

RESUMO

The proteome of the Pakistani B. sindanus venom was investigated with reverse-phase HPLC and nano-ESI-LCMS/MS analysis. At least 36 distinct proteins belonging to 8 toxin protein families were identified. Three-finger toxin (3FTx), phospholipase A2 (including ß-bungarotoxin A-chains) and Kunitz-type serine protease inhibitor (KSPI) were the most abundant, constituting ~95% of total venom proteins. The other toxin proteins of low abundance are snake venom metalloproteinase (SVMP), L-amino acid oxidase (LAAO), acetylcholinesterase (AChE), vespryn and cysteine-rich secretory protein (CRiSP). The venom was highly lethal to mice with LD50 values of 0.04 µg/g (intravenous) and 0.15 µg/g (subcutaneous). The 3FTx proteins are diverse, comprising kappa-neurotoxins, neurotoxin-like protein, non-conventional toxins and muscarinic toxin-like proteins. Kappa-neurotoxins and ß-bungarotoxins represent the major toxins that mediate neurotoxicity in B. sindanus envenoming. Alpha-bungarotoxin, commonly present in the Southeast Asian krait venoms, was undetected. The Indian VINS Polyvalent Antivenom (VPAV) was immunoreactive toward the venom, and it moderately cross-neutralized the venom lethality (potency = 0.25 mg/ml). VPAV was able to reverse the neurotoxicity and prevent death in experimentally envenomed mice, but the recovery time was long. The unique toxin composition of B. sindanus venom may be considered in the formulation of a more effective pan-regional, polyspecific antivenom. BIOLOGICAL SIGNIFICANCE: Bungarus sindanus, an endemic krait species distributed mainly in the Sindh Province of Pakistan is a cause of snake envenomation. Its specific antivenom is, however, lacking. The proteomic study of its venom revealed a substantial presence of κ-bungarotoxins and ß-bungarotoxins. The toxin profile corroborates the potent neurotoxicity and lethality of the venom tested in vivo. The heterologous Indian VINS polyvalent antivenom (VPAV) cross-reacted with B. sindanus venom and cross-neutralized the venom neurotoxicity and lethality in mice, albeit the efficacy was moderate. The findings imply that B. sindanus and the phylogenetically related B. caeruleus of India share certain venom epitopes. Research should be advanced to improve the efficacy spectrum of a pan-regional polyspecific antivenom.


Assuntos
Antivenenos , Bungarotoxinas , Bungarus/metabolismo , Proteoma , Animais , Antivenenos/química , Antivenenos/farmacologia , Bungarotoxinas/antagonistas & inibidores , Bungarotoxinas/metabolismo , Bungarotoxinas/toxicidade , Reações Cruzadas , Camundongos , Paquistão , Proteoma/antagonistas & inibidores , Proteoma/metabolismo , Proteoma/toxicidade
15.
J Proteomics ; 175: 156-173, 2018 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-29278784

RESUMO

Naja naja is a medically important species that is distributed widely in South Asia. Its venom lethality and neutralization profile have been reported to vary markedly, but the understanding of this phenomenon has been limited without a comprehensive venom profile for the Pakistani N. naja. This study set to investigate the venom proteome of Pakistani N. naja applying reverse-phase HPLC, SDS-PAGE, mass spectrometry and data-mining approaches. The venom enzymatics and antigen binding activities were also studied. A total of 55 venom proteins comprising 11 toxin families were identified, with three-finger toxins (75.29%) being the predominant component, followed by phospholipase A2 (14.24%) and other proteins (<5%). The enzyme activities of most of the venom components were also detected in this work. The high abundance of long neurotoxins (LNTX, 21.61%) in the Pakistani N. naja venom is varied from that reported for N. naja venoms from other geographical origins. The venom exhibited high immunoreactivity toward Naja kaouthia monovalent antivenom (NKMAV), which was raised against the LNTX-predominated heterologous Thai N. kaouthia venom. Together, the findings show that the Pakistani N. naja venom is predominated by LNTX, and this unique property correlates with its high lethality and effective neutralization by the heterologous NKMAV. BIOLOGICAL SIGNIFICANCE: This study reveals the compositional details of the venom proteome of Pakistani spectacled cobra (Naja naja). The protein subtypes, proteoforms, and relative abundances of individual proteins were comprehensively revealed in this study, following a venom decomplexing proteomic approach. The Pakistani cobra venom is unique among the rest of the N. naja venom composition reported thus far, as it contains a high abundance of alpha-neurotoxins (predominated by long neurotoxins); these are highly potent post-synaptic neuromuscular blockers that cause paralysis and are principal toxins that account for the high lethality of the venom (LD50=0.2µg/g in mice). In contrast, previous reports showed that the N. naja venoms of India and Sri Lanka had a lower content of neurotoxins and a relatively higher value of LD50. The Pakistani cobra venom demonstrated sufficient immunoreactivity toward three antivenom products manufactured outside Pakistan (including the Indian product VINS), however the potency of antigen binding was the highest toward Naja kaouthia monovalent antivenom, a heterologous antivenom raised against a long neurotoxin-predominated venom of the Thai monocled cobra. From the practical standpoint, the findings indicate that the treatment of N. naja envenomation in Pakistan may be improved by the production of a locale-specific antivenom, in which the antivenom produced contains more antibodies that can target and react more specifically with the highly abundant lethal neurotoxins in the Pakistani N. naja venom.


Assuntos
Venenos Elapídicos/química , Naja naja , Proteoma/análise , Proteômica/métodos , Animais , Antivenenos , Variação Biológica da População , Venenos Elapídicos/análise , Geografia , Neurotoxinas/análise , Paquistão , Fosfolipases A2/análise , Toxinas Biológicas/análise
16.
RSC Adv ; 8(7): 3599-3610, 2018 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-35542905

RESUMO

Here, we report the facile synthesis of graphene oxide-gold (GO-Au) nanocomposites and their use as adsorbents for the removal of toxic industrial dyes from water and as catalysts for the individual and simultaneous reduction of a dye and a nitro compound in aqueous medium. GO sheets were prepared using a modified Hummers method while Au nanoparticles were integrated on GO sheets by reducing Au(iii) ions on the surfaces of GO sheets using sodium citrate as a reducing agent. The prepared composite was characterized with field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), elemental dispersive X-ray analysis (EDX), X-ray diffraction (XRD), Fourier transform infra-red (FT-IR) spectroscopy and thermal gravimetric analysis (TGA). The GO-Au nanocomposite demonstrated efficient adsorption capacities and recyclability for malachite green (MG) and ethyl violet (EV) dyes. The effects of various experimental parameters including temperature, pH, contact time, and adsorbent dose were studied. From the simulation of experimental data with different adsorption isotherms and kinetic models it was found that the adsorption of both the dyes followed the Freundlich adsorption model and a pseudo-second order kinetic model, respectively. Moreover, the adsorbent showed better recyclability for both dyes without any compromise on the removal efficiency. Similarly, the catalytic performance for the reduction of 2-nitroaniline (2-NA) has been investigated in detail by using the prepared nanocomposite as a catalyst. Most importantly, we reported the simultaneous adsorption of cationic and anionic dyes from water using the prepared nanocomposite as well as the simultaneous catalytic reduction of a mixture of EV and 2-NA. So, considering the facile synthesis process and the efficient removal of a variety of dyes and the catalytic performance this work opens up a tremendous opportunity to bring GO based nanocomposites from experimental research to practically applied materials for wastewater treatment.

17.
J Exp Bot ; 66(22): 7129-49, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26314767

RESUMO

Circadian clocks are a great evolutionary innovation and provide competitive advantage during the day/night cycle and under changing environmental conditions. The circadian clock mediates expression of a large proportion of genes in plants, achieving a harmonious relationship between energy metabolism, photosynthesis, and biotic and abiotic stress responses. Here it is shown that multiple paralogues of clock genes are present in soybean (Glycine max) and mediate flooding and drought responses. Differential expression of many clock and SUB1 genes was found under flooding and drought conditions. Furthermore, natural variation in the amplitude and phase shifts in PRR7 and TOC1 genes was also discovered under drought and flooding conditions, respectively. PRR3 exhibited flooding- and drought-specific splicing patterns and may work in concert with PRR7 and TOC1 to achieve energy homeostasis under flooding and drought conditions. Higher expression of TOC1 also coincides with elevated levels of abscisic acid (ABA) and variation in glucose levels in the morning and afternoon, indicating that this response to abiotic stress is mediated by ABA, endogenous sugar levels, and the circadian clock to fine-tune photosynthesis and energy utilization under stress conditions. It is proposed that the presence of multiple clock gene paralogues with variation in DNA sequence, phase, and period could be used to screen exotic germplasm to find sources for drought and flooding tolerance. Furthermore, fine tuning of multiple clock gene paralogues (via a genetic engineering approach) should also facilitate the development of flooding- and drought-tolerant soybean varieties.


Assuntos
Processamento Alternativo , Relógios Biológicos/genética , Genes de Plantas , Glycine max/genética , Ácido Abscísico/metabolismo , Sequência de Aminoácidos , Ciclopentanos/metabolismo , Secas , Inundações , Dados de Sequência Molecular , Oxilipinas/metabolismo , Proteínas de Plantas/genética , Alinhamento de Sequência , Fatores de Transcrição/metabolismo
18.
J Hand Surg Eur Vol ; 38(9): 984-90, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23456926

RESUMO

The diaphysial axis-metacarpal head angle (DHA) is the angle formed between the longitudinal axis of the diaphysis of the proximal phalanx and central point of the metacarpal head. The normal DHA ranges from 177.1° and 180.0°. There were no significant differences between DHA measurements when taken by the same observer at two separate occasions (P = 0.986) or when taken by two different observers (P = 0.948). We have put an algorithm of management of paediatric phalangeal base fractures incorporating the DHA in the decision making. A prospective study of 92 children (5-14 years) with phalangeal base fractures was conducted. Closed reduction was possible in all but one case in which open reduction and K-wire fixation was required. Closed reduction of the remaining 91 fractures yielded a 'good' reduction in 80 cases (no finger deformity on clinical examination with a post-reduction DHA greater than 177°). After a mean follow-up of 4.2 months, all these 80 cases qualified for an excellent outcome as per Al-Qattan's criteria. The remaining 11 children were considered to have an 'acceptable' reduction (no scissoring, but there was a mild residual lateral deviation of the finger with a DHA angle of 169.4° to 176.2°). At a mean follow-up of 28 months, all these 11 mal-united fractures remodelled with normalization of the DHA; and all 11 children qualified for an excellent outcome as per Al-Qattan's criteria. The current series stresses on the advantages of using DHA in the objective assessment of paediatric phalangeal base fractures and demonstrates the remodelling of fractures with about 10° of lateral deviation.


Assuntos
Falanges dos Dedos da Mão/anatomia & histologia , Falanges dos Dedos da Mão/lesões , Fraturas Ósseas/terapia , Ossos Metacarpais/anatomia & histologia , Adolescente , Criança , Pré-Escolar , Diáfises/anatomia & histologia , Diáfises/diagnóstico por imagem , Feminino , Falanges dos Dedos da Mão/diagnóstico por imagem , Falanges dos Dedos da Mão/cirurgia , Seguimentos , Fixação Interna de Fraturas , Consolidação da Fratura , Humanos , Masculino , Manipulação Ortopédica , Ossos Metacarpais/diagnóstico por imagem , Variações Dependentes do Observador , Estudos Prospectivos , Radiografia , Reprodutibilidade dos Testes , Contenções , Fita Cirúrgica
19.
Trends Plant Sci ; 17(10): 616-23, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22743067

RESUMO

More than 60% of intron-containing genes undergo alternative splicing (AS) in plants. This number will increase when AS in different tissues, developmental stages, and environmental conditions are explored. Although the functional impact of AS on protein complexity is still understudied in plants, recent examples demonstrate its importance in regulating plant processes. AS also regulates transcript levels and the link with nonsense-mediated decay and generation of unproductive mRNAs illustrate the need for both transcriptional and AS data in gene expression analyses. AS has influenced the evolution of the complex networks of regulation of gene expression and variation in AS contributed to adaptation of plants to their environment and therefore will impact strategies for improving plant and crop phenotypes.


Assuntos
Processamento Alternativo , Regulação da Expressão Gênica de Plantas , Plantas/metabolismo , RNA Mensageiro/metabolismo , RNA de Plantas/metabolismo , Relógios Circadianos , Epigênese Genética , Evolução Molecular , Genes de Plantas , Degradação do RNAm Mediada por Códon sem Sentido , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas/genética , Poliploidia , Estabilidade Proteica , RNA Mensageiro/genética , RNA de Plantas/genética , Transcrição Gênica
20.
Nucleic Acids Res ; 40(6): 2454-69, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22127866

RESUMO

Alternative splicing (AS) coupled to nonsense-mediated decay (NMD) is a post-transcriptional mechanism for regulating gene expression. We have used a high-resolution AS RT-PCR panel to identify endogenous AS isoforms which increase in abundance when NMD is impaired in the Arabidopsis NMD factor mutants, upf1-5 and upf3-1. Of 270 AS genes (950 transcripts) on the panel, 102 transcripts from 97 genes (32%) were identified as NMD targets. Extrapolating from these data around 13% of intron-containing genes in the Arabidopsis genome are potentially regulated by AS/NMD. This cohort of naturally occurring NMD-sensitive AS transcripts also allowed the analysis of the signals for NMD in plants. We show the importance of AS in introns in 5' or 3'UTRs in modulating NMD-sensitivity of mRNA transcripts. In particular, we identified upstream open reading frames overlapping the main start codon as a new trigger for NMD in plants and determined that NMD is induced if 3'-UTRs were >350 nt. Unexpectedly, although many intron retention transcripts possess NMD features, they are not sensitive to NMD. Finally, we have shown that AS/NMD regulates the abundance of transcripts of many genes important for plant development and adaptation including transcription factors, RNA processing factors and stress response genes.


Assuntos
Processamento Alternativo , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Genes Reguladores , Degradação do RNAm Mediada por Códon sem Sentido , Regiões 3' não Traduzidas , Arabidopsis/efeitos dos fármacos , Proteínas de Arabidopsis/genética , Códon de Iniciação , Códon sem Sentido , Cicloeximida/farmacologia , Genes de Plantas , Íntrons , Degradação do RNAm Mediada por Códon sem Sentido/efeitos dos fármacos , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , RNA Helicases/genética , RNA Mensageiro/química , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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