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1.
Comput Biol Med ; 177: 108646, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38824788

RESUMO

Improved data sharing between healthcare providers can lead to a higher probability of accurate diagnosis, more effective treatments, and enhanced capabilities of healthcare organizations. One critical area of focus is brain tumor segmentation, a complex task due to the heterogeneous appearance, irregular shape, and variable location of tumors. Accurate segmentation is essential for proper diagnosis and effective treatment planning, yet current techniques often fall short due to these complexities. However, the sensitive nature of health data often prohibits its sharing. Moreover, the healthcare industry faces significant issues, including preserving the privacy of the model and instilling trust in the model. This paper proposes a framework to address these privacy and trust issues by introducing a mechanism for training the global model using federated learning and sharing the encrypted learned parameters via a permissioned blockchain. The blockchain-federated learning algorithm we designed aggregates gradients in the permissioned blockchain to decentralize the global model, while the introduced masking approach retains the privacy of the model parameters. Unlike traditional raw data sharing, this approach enables hospitals or medical research centers to contribute to a globally learned model, thereby enhancing the performance of the central model for all participating medical entities. As a result, the global model can learn about several specific diseases and benefit each contributor with new disease diagnosis tasks, leading to improved treatment options. The proposed algorithm ensures the quality of model data when aggregating the local model, using an asynchronous federated learning procedure to evaluate the shared model's quality. The experimental results demonstrate the efficacy of the proposed scheme for the critical and challenging task of brain tumor segmentation. Specifically, our method achieved a 1.99% improvement in Dice similarity coefficient for enhancing tumors and a 19.08% reduction in Hausdorff distance for whole tumors compared to the baseline methods, highlighting the significant advancement in segmentation performance and reliability.


Assuntos
Algoritmos , Neoplasias Encefálicas , Humanos , Neoplasias Encefálicas/diagnóstico por imagem , Blockchain , Aprendizado de Máquina , Privacidade , Imageamento por Ressonância Magnética/métodos
2.
Cureus ; 16(4): e58380, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38756297

RESUMO

Pharmacomechanical therapy and catheter-directed thrombolysis are potent treatments for venous thromboembolism. However, limited data exist regarding the management of thrombi in the inferior vena cava (IVC). IVC thrombus resulting from tumors is a particularly uncommon condition. Managing IVC tumor thrombi poses even greater challenges, as conventional therapies such as systemic anticoagulation and thrombolysis are often ineffective. In this report, we present the case of a 73-year-old male with an inferior vena cava tumor thrombus successfully managed through aspiration thrombectomy utilizing the Inari FlowTriever system.

3.
Eur J Pharm Sci ; 198: 106797, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38735401

RESUMO

The multicomponent etiology, complex clinical implications, dose-based side effect and degree of pain mitigation associated with the current pharmacological therapy is incapable in complete resolution of chronic neuropathic pain patients which necessitates the perpetual requirement of novel medication therapy. Therefore, this study explored the ameliorative aptitude of two novel methanimine imitative like (E)-N-(4-nitrobenzylidene)-4­chloro-2-iodobenzamine (KB 09) and (E)-N-(4-methylbenzylidene)-4­chloro-2-iodobenzamine (KB 10) in chronic constriction injury (CCI) of sciatic nerve induced neuropathic pain in rat model. Standard behavioral tests like dynamic and static allodynia, cold, thermal and mechanical hyperalgesia along with rotarod activity were performed at various experimental days like 0, 3, 7, 14 and 21. Enzyme linked immunosorbent assay (ELISA) on spinal tissue and antioxidant assays on sciatic nerve were executed accompanied by molecular docking and simulation studies. Prolonged ligation of sciatic nerve expressively induced hyperalgesia as well as allodynia in rats. KB 09 and KB 10 substantially attenuated the CCI elicited hyperalgesia and allodynia. They significantly reduced the biomarkers of pain and inflammation like Interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) in ELISA and while enhanced the GSH, SOD and CAT and diminished the MDA levels during antioxidant assays. KB 09 displayed -9.62 kcal/mol with TNF-α and -7.68 kcal/mol binding energy with IL-6 whereas KB 10 exhibited binding energy of -8.20 kcal/mol with IL-6 while -11.68 kcal/mol with TNF-α and hence both trial compounds ensured stable interaction with IL-6 and TNF-α during computational analysis. The results advocated that both methanimine derivatives might be novel candidates for attenuation of CCI-induced neuropathic pain prospects via anti-nociceptive, anti-inflammatory and antioxidant mechanisms.


Assuntos
Hiperalgesia , Simulação de Acoplamento Molecular , Neuralgia , Nervo Isquiático , Animais , Neuralgia/tratamento farmacológico , Neuralgia/metabolismo , Masculino , Hiperalgesia/tratamento farmacológico , Nervo Isquiático/lesões , Nervo Isquiático/efeitos dos fármacos , Ratos , Ratos Wistar , Modelos Animais de Doenças , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-6/metabolismo , Analgésicos/farmacologia , Analgésicos/uso terapêutico , Analgésicos/química , Antioxidantes/farmacologia , Antioxidantes/química , Simulação por Computador , Constrição , Iminas/química , Iminas/farmacologia
4.
Heliyon ; 9(11): e22483, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38074891

RESUMO

Neurodegenerative complications, like Alzheimer's disease (AD) exert adverse effects i.e. psychological and physiological in the central nervous system. The synthetic drugs used for these complications have negative effects on body health and therefore natural remedies are a good and targeted approach to counter such complications. Alternatively, fruits and a variety of biochemicals which are an important source of diet, can be used for remedial purposes. Due to the antioxidant properties of polyphenolic compounds, several companies utilize this property to advertise polyphenol-rich beverages. Pomegranate (Punica granatum L.), is one such fruit that is well known for its medical usage due to its antioxidant properties. In the cuurent study a literature search survey was performed on traditional uses, phytochemicals on pomegranate and their medical applications especaily in neurodegenerative deasese using electronic data bases like PubMed, Google Scholar, Scopus, Science Direct Wikipedia and Springer Nature. Based on previous preclinical and clinical studies, pomegranate juice, extracts, and its bioactive constituents have shown many mitigating properties, including suppression of inflammatory cell signaling, reduction in expression of genes associated with oxidative stress as well as pro-inflammatory cytokines in neurons, decreased production of inflammatory and oxidative stress biomarkers and increased expression of endothelial nitric oxide synthase. It also decreases the expression of soluble amyloid protein procurer ß (sAPPß), ß-secretase and carboxyl terminal fragment ß (CTFß). Similarly, during an in-vivo study on APP/PS1 mice, pomegranate supplementation has been shown to impart cognitive aid by the protection of neurons and triggering neurogenesis through anti-inflammatory signaling pathway. In conclusion, pomegranate supplementation can be a promising source of protection against Alzheimer's disease.

5.
Neurotoxicology ; 99: 274-281, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37939858

RESUMO

Ethanol administration triggers an inflammatory response that leads to a complex series of immune responses including the release of an excessive amount of inflammatory mediators particularly tumor necrosis factor (TNF-α) and nuclear factor-kB (NF-KB) which produce a large amount of reactive oxygen species. The inflammatory-induced cytotoxicity is increased when the PI3-kinase/Akt pathway is inhibited. Some studies have also shown that ethanol suppresses the PI3-kinase signaling pathway induced by receptor activation. Friedelin and Glutinol belong to pentacyclic triterpenoid class and are known for their anti-inflammatory and antioxidant properties. The present study was aimed to elucidate the effects of these phytoconstituents on one of the key ethanol-induced neuronal damage pathways. The pups having (5-7 g average body weight) were used and randomly divided into groups. The control and ethanol treated pups were administered 0.9% normal saline while treated pups received glutinol and friedelin (30 mg/kg subcutaneously) respectively. After four hours all the experimental animals were sacrificed and their brains were collected carefully for protein expression analysis of p-Akt, TNF-α, NF-KB, caspase-3 and PARP-1 employing immunoblotting technique. Hemolytic, DNA protection, chelating power and ß-carotene assays results revealed that freidelin and glutinol are safe for parenteral administration. Glutinol administration with ethanol significantly abridged the ethanol induced over expression of TNF-α, caspase-3 and PARP-1 in pup's brain. Similarly, freidelin attenuated the neurodegeneration by inhibiting the ethanol induced p-JNK and NF-kB expression in pups' brain. This protection may be attributed to the revival of p-Akt signaling for cell survival. It is concluded that the present study demonstrates the neuro-protective effects of friedelin and glutinol via modulating the capase-3 and PARP-1 expression and modulating the neuronal apoptotic pathways.


Assuntos
Lupanos , NF-kappa B , Neuroproteção , Fator de Necrose Tumoral alfa , Animais , Encéfalo , Caspase 3/metabolismo , Etanol/toxicidade , NF-kappa B/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Lupanos/farmacologia
6.
Environ Geochem Health ; 45(3): 1013-1026, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35635682

RESUMO

The current study features PAHs exposure on Karakoram Highway, a route of utmost importance in Pakistan. The drivers of heavy traffic vehicles (HTV) on Karakoram Highway spend long hours amid dense traffic and therefore, inevitably inhale huge amount of PAH carcinogens. The urinary metabolites of PAHs in such drivers (meeting selection criteria n = 48) and a control group (n = 49) were comparatively profiled. The higher urinary biomarkers among ninety-six percent HTV drivers were evident of PAHs exposure. We observed elevated concentrations of urinary benzo[a]pyrene metabolites (3-OH-BaP = 3.53 ± 0.62 ng g-1 creatinine and 9-OH-BaP = 3.69 ± 0.74 ng g-1 creatinine) in HTV driver's samples compared to controls (0.85 ± 0.08 and 0.31 ± 0.03 ng g-1 creatinine, respectively). Interestingly, urinary benzo[a]pyrene metabolites were detected in almost similar amount among HTV drivers irrespective of their working hours. A distinct smoking effect was manifested with rising urinary levels of 1-hydroxypyrene, 2-hydroxyphenanthrene, and 3-hydroxybenzo[a]pyrene with corresponding increase in driving hours per day. These metabolites exhibited characteristic exposures to low molecular weight volatile PAHs that are commonly found in vehicular exhaust. The elevated PAH body burden was directly linked to the nature of their job and the route-long environmental pollution on Karakoram Highway. Additionally, the poor economic status and smoking also increased HTV driver's health vulnerability and significantly declined their health capacity. There was conclusive evidence that HTV drivers were exposed to PAHs during a ride on Karakoram Highway, back and forth, an aspect not reported earlier.


Assuntos
Exposição Ocupacional , Hidrocarbonetos Policíclicos Aromáticos , Benzo(a)pireno/análise , Exposição Ocupacional/análise , Creatinina , Monitoramento Ambiental/métodos , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/urina , Pirenos/metabolismo , Biomarcadores/urina
7.
J Inflamm Res ; 15: 3643-3660, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35783245

RESUMO

Introduction: Several studies revealed that alcohol utilization impairs memory in adults; however, the underlying mechanism is still unclear. The production of inflammatory markers and reactive oxygen species (ROS) plays a major role in neurodegeneration, which leads to memory impairment. Therefore, targeting neuroinflammation and oxidative distress could be a useful strategy for abrogating the hallmarks of ethanol-induced neurodegeneration. Moreover, several studies have demonstrated multiple biological activities of thiazolidine derivatives including neuroprotection. Methods: In the current study, we synthesized ten (10) new thiazolidine-4-carboxylic acid derivatives (P1-P10), characterized their synthetic properties using proton nuclear magnetic resonance (1H-NMR) and carbon-13 NMR, and further investigated the neuroprotective potential of these compounds in an ethanol-induced neuroinflammation model. Results: Our results suggested altered levels of antioxidant enzymes associated with an elevated level of tumor necrosis factor-alpha (TNF-α), nuclear factor-κB (p-NF-κB), pyrin domain-containing protein 3 (NLRP3), and cyclooxygenase-2 (COX-2) in ethanol-treated animals. Ethanol treatment also led to memory impairment in rats, as assessed by behavioral tests. To further support our notion, we performed molecular docking studies, and all synthetic compounds exhibited a good binding affinity with a fair bond formation with selected targets (NF-κB, TLR4, NLRP3, and COX-2). Discussion: Overall, our results revealed that these derivatives may be beneficial in reducing neuroinflammation by acting on different stages of inflammation. Moreover, P8 and P9 treatment attenuated the neuroinflammation, oxidative stress, and memory impairment caused by ethanol.

8.
J Inflamm Res ; 15: 3873-3890, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35845091

RESUMO

Objective: The study investigated the effect of newly synthesized benzimidazole derivatives against ethanol-induced neurodegeneration. According to evidence, ethanol consumption may cause a severe insult to the central nervous system (CNS), resulting in mental retardation, neuronal degeneration, and oxidative stress. Targeting neuroinflammation and oxidative stress may be a useful strategy for preventing ethanol-induced neurodegeneration. Methodology: Firstly, the newly synthesized compounds were subjected to molecular simulation and docking in order to predict ligand binding status. Later, for in vivo observations, adult male Sprague Dawley rats were used for studying behavioral and oxidative stress markers. ELIZA kits were used to analyse tumour necrosis factor-alpha (TNF-), nuclear factor-B (NF-B), interleukin (IL-18), and pyrin domain-containing protein 3 (NLRP3) expression, while Western blotting was used to measure IL-1 and Caspase-1 expression. Results: Our findings suggested that altered levels of antioxidant enzymes were associated with elevated levels of TNF-α, NF-B, IL-1, IL-18, Caspase-1, and NLRP3 in the ethanol-treated group. Furthermore, ethanol also caused memory impairment in rats, as measured by behavioural tests. Pretreatment using selected benzimidazole significantly increased the combat of the brain against ethanol-induced oxidative stress. The neuroprotective effects of benzimidazole derivatives were promoted by their free radical scavenging activity, augmentation of endogenous antioxidant proteins (GST, GSH), and amelioration of lipid peroxide (LPO) and other pro-inflammatory mediators. Molecular docking and molecular simulation studies further supported our hypothesis that the synthetic compounds Ca and Cb had an excellent binding affinity with proper bond formation with their targets (TNF-α and NLRP3). Conclusion: It is revealed that these benzimidazole derivatives can reduce ethanol-induced neuronal toxicity by regulating the expression of cytokines, antioxidant enzymes, and the inflammatory cascade.

9.
Biomed Pharmacother ; 150: 112956, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35447548

RESUMO

Western diet style (fast food), which includes fatty frozen junk food, lard, processed meats, whole-fat dairy foods, cream, mayonnaise, butter, snacks, and fructose, is a primary etiological determinant for developing nonalcoholic steatohepatitis (NASH) worldwide. Here the primary focus is to see the impact of naturally identified essential oil on disease mechanisms developed in an animal model using the same ingredients. Currently, symptomatic therapies are recommended for the management of NASH due to non-availability of specific treatments. Therefore, the present study was designed to evaluate the potential anti-NASH effect of nerolidol in a rat model fed with a purpose-built diet. The diet substantially induced insulin resistance, hepatic steatosis, dyslipidemia, and elevation of liver enzymes in the experimental animals. The levels of liver oxidative stress markers, nitrites (NO2-), serum pro-inflammatory cytokine (TNF-α) and hepatic collagen were increased in disease control rats. Nerolidol oral treatment in ascending dose order of 250 and 500 mg/kg substantially reduced the steatosis (macrovesicular and microvesicular), degeneration of hepatocytes, and inflammatory cells infiltration. The amounts of circulatory TNF-α and tissue collagen were also reduced at 500 mg/kg dose of nerolidol, expressing its anti-fibrotic effect. The current study described the multiple-hit pathophysiology of NASH as enhanced steatosis, pro-inflammatory markers, and oxidative stress in rats, which resulted in the development of vicious insulin resistance. Nerolidol treatment significantly reduced hepatic lipid accumulation and halted disease progression induced by a hypercaloric diet.


Assuntos
Resistência à Insulina , Hepatopatia Gordurosa não Alcoólica , Animais , Dieta Hiperlipídica , Dieta Ocidental , Modelos Animais de Doenças , Regulação para Baixo , Inflamação/patologia , Fígado/patologia , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/patologia , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/patologia , Ratos , Sesquiterpenos , Fator de Necrose Tumoral alfa
10.
Saudi Pharm J ; 30(12): 1791-1801, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36601515

RESUMO

Noscapine hydrochloride (benzyl-isoquinoline antitussive alkaloid) is an opium derivative and generally used as a cough suppressant. Numerous studies on noscapine hydrochloride have reported that it has potent anti-inflammatory activity. However, the mechanisms by which it exerts an anti-inflammatory function is not well understood. Protein denaturation is the primary step that leads to the organ destruction and permanent arthritic disability. The above-mentioned facts provided the ground to plan this study using different in-vitro and in-vivo approaches. RT-qPCR and ELISA assays were used to assess the inflammatory markers related to protein denaturation in complete adjuvant persuaded rheumatism in Sprague - Dawley rats. The results were collected as paw volume and body weight changes, arthritic scoring and serum antioxidant enzymes assays. These findings demonstrated that all doses of noscapine hydrochloride (10, 20 and 40 mg/kg) studied in this study, significantly (p < 0.001) decreased the protein denaturation by preventing the increase in levels of interleukin-1ß (IL-1ß), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), nuclear factor-kB (NF-kB), cyclooxygenase-2 (COX-2) and prostaglandin E2. Noscapine hydrochloride significantly reduced the paw volume (p < 0.001), arthritic scoring and reversed the body mass as compared to arthritic control diseased rats.

11.
J Inflamm Res ; 14: 5659-5679, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34754213

RESUMO

OBJECTIVE: The study investigated the effect 5-[(naphthalen-2-yloxy) methyl]-1,3,4-oxadiaszole2-thiol (B3) in animal model of acute epileptic shock. METHODS: The pharmacokinetics profile of B3 was checked through SwissADME software. The binding affinities of B3, diazepam, and flumazenil (FLZ) were obtained through Auto Dock and PyRx. Post docking analysis and interpretation of hydrogen bonds were performed through Discovery Studio Visualizer 2016. Molecular dynamics simulations of three complexes were carried out through Desmond software package. B3 was then proceeded in PTZ-induced acute seizures models. Flumazenil was used in animal studies for elucidation of possible mechanism of B3. After behavioral studies, the animals were sacrificed, and the brain samples were isolated and stored in 4% formalin for molecular investigations including H and E staining, IHC staining and Elisa etc. RESULTS: The results demonstrate that B3 at 20 and 40 mg/kg prolonged the onset time of generalized seizures. B3 considerably increased the expression of protective glutathione S-transferase and glutathione reductase and reduced lipid peroxidation and inducible nitric oxide synthase (P < 0.001) in the cortex. B3 significantly suppressed (P < 0.01) the over expression of the inflammatory mediator tumor necrosis factor-α, whose up-regulation is reported in acute epileptic shocks. CONCLUSION: Hence, it is concluded from the aforementioned results that B3 provides neuroprotective effects PTZ-induced acute epileptic model. FLZ pretreatment resulted in inhibition of the anticonvulsant effect of B3. B3 possesses anticonvulsant effect which may be mediated through GABAA mediated antiepileptic pathway.

12.
Chemosphere ; 260: 127652, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32688325

RESUMO

Cadmium (Cd) contamination in soil negatively impacts crop productivity, grain quality, and human health. Wheat seeds, with different concentrations of intrinsic zinc (Zn): low Zn (35 mg kg-1), medium (42 mg kg-1), and high Zn (49 mg kg-1), were planted in artificially contaminated soil (10 mg Cd kg-1 soil). Zinc (5 g kg-1) and biochar (20 g kg-1 soil) were applied alone or in combination at sowing. Cadmium contamination reduced wheat growth, productivity, and grain Zn concentration, relative to the respective no-Cd treatments, with greater reductions in plants with low intrinsic Zn. Among the soil amendments, Zn and/or biochar improved wheat productivity and grain Zn and reduced grain Cd concentration in plants grown from seed with varying intrinsic Zn levels. Plants from high intrinsic Zn seeds performed better under Cd stress with the application of soil amendments than seeds with low or medium intrinsic Zn levels. The combined application of Zn and biochar had the highest increases in grain yield (9.51%) and grain Zn concentration (12.2%), relative to the control (no Cd, no Zn, and no biochar). This treatment also decreased the Cd concentrations in straw (7.1%) and grain (95.6%). The sole application of Zn or biochar improved wheat productivity and grain Zn concentration and deceased grain Cd concentration under Cd stress, but more improvements resulted from the combined application of Zn and biochar. Plants grown from seed with high Zn were better able to tolerate Cd stress than the plants raised from seeds with medium and low Zn levels.


Assuntos
Cádmio/toxicidade , Poluentes do Solo/toxicidade , Triticum/fisiologia , Zinco/análise , Pão , Cádmio/química , Carvão Vegetal , Grão Comestível/química , Poluição Ambiental , Humanos , Sementes/química , Solo , Poluentes do Solo/análise , Poluentes do Solo/química , Triticum/crescimento & desenvolvimento
13.
J Coll Physicians Surg Pak ; 29(1): 66-69, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30630573

RESUMO

OBJECTIVE: To analyse the diagnostic performance of MTB/RIF assay for the diagnosis of pulmonary tuberculosis and detection of rifampicin resistance using sputum samples. STUDY DESIGN: Observational cross-sectional study. PLACE AND DURATION OF STUDY: Provincial TB Reference Laboratory (PTRL), Hayatabad Medical Complex, Peshawar, Pakistan, from January to October 2015. METHODOLOGY: A total of 268 participants were consecutively enrolled in the study after meeting the inclusion criteria. Their sputum samples were collected and processed by N-acetyl-L-cysteine-sodium hydroxide (NALC-NaOH) method and GeneXpert MTB/RIF assay. RESULTS: This study determined the overall sensitivity and specificity of MTB/RIF assay, it was 92.4% (86/93) and 97.1% (138/142), respectively. The sensitivity was 98.4% (60/61) in culture proven smear positive samples, whilst sensitivity in culture proven smear negative samples was 93.7% (30/32), using culture as reference standard. CONCLUSION: GeneXpert MTB/RIF assay could greatly improve early diagnosis of PTB in smear negative cases as well as multidrug resistant tuberculosis.


Assuntos
Antibióticos Antituberculose/uso terapêutico , Técnicas de Diagnóstico Molecular/métodos , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/genética , Reação em Cadeia da Polimerase/métodos , Rifampina/uso terapêutico , Escarro/microbiologia , Tuberculose Resistente a Múltiplos Medicamentos , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/tratamento farmacológico , Técnicas Bacteriológicas/métodos , Estudos Transversais , Feminino , Humanos , Masculino , Mycobacterium tuberculosis/isolamento & purificação , Sensibilidade e Especificidade , Análise de Sequência de DNA/métodos
14.
Mol Biol Rep ; 45(4): 565-570, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29926385

RESUMO

Autosomal recessive osteopetrosis is a severe fatal disorder with an average incidence of around 1:250,000. It is diagnosed soon after birth or within the 1st year of life with severe symptoms of abnormal bone remodelling. This study was aimed to identify the underlying genetic cause of the disease in a Pakistani family segregating infantile malignant osteopetrosis in autosomal recessive pattern. Whole exome sequencing of the proband was performed using the 51 Mb SureSelect V4 library kit and sequenced using the Illumina HiSeq2500 sequencing system. The reads were analysed using standard bioinformatic data analysis pipeline. The genotype of candidate variants was confirmed in the proband and his normal parents by Sanger sequencing. Two novel homozygous missense variants were found in the same codon 204 of CLCN7 NM_001287.5:c.[610A>T;612C>G] predicting p.(Ser204Trp) variant in the protein. Sanger sequencing and RFLP assay verified that both these variants were heterozygous in the unaffected parents. Moreover, these variants were not detected in the unrelated healthy Pakistani subjects (200 chromosomes), ExAC, dbSNP, or the 1000 Genomes Project data. Multiple bioinformatics tools unanimously predicted the p.(Ser204Trp) variant as deleterious. CLCN7 mutation p.(Ser204Trp) is the likely cause of the osteopetrosis disease in the Pakistani family. This study expands the restricted spectrum of CLCN7 mutations associated with infantile malignant osteopetrosis and indicates clinical significance of whole exome sequencing in the diagnosis of clinically and genetically heterogenous osteopetrosis phenotype. These data should be helpful in the improved genetic counselling, carrier identification and prenatal diagnosis of the affected family.


Assuntos
Canais de Cloreto/genética , Canais de Cloreto/fisiologia , Osteopetrose/genética , Adulto , Códon/genética , Exoma , Feminino , Genótipo , Homozigoto , Humanos , Recém-Nascido , Masculino , Mutação , Mutação de Sentido Incorreto/genética , Paquistão , Linhagem , Fenótipo , Sequenciamento do Exoma/métodos
16.
Mol Pharmacol ; 93(6): 601-611, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29588343

RESUMO

The pharmacological targeting of the α7 nicotinic acetylcholine receptor (α7) is a promising strategy in the development of new drugs for neurologic diseases. Because α7 receptors regulate cellular calcium, we investigated how the prototypical type II-positive allosteric modulator PNU120596 affects α7-mediated calcium signaling. Live imaging experiments show that PNU120596 augments ryanodine receptor-driven calcium-induced calcium release (CICR), inositol-induced calcium release (IICR), and phospholipase C activation by the α7 receptor. Both influx of calcium through the α7 nicotinic acetylcholine receptor (nAChR) channel as well as the binding of intracellular G proteins were involved in the effect of PNU120596 on intracellular calcium. This is evidenced by the findings that chelation of extracellular calcium, expression of α7D44A or α7345-348A mutant subunits, or blockade of calcium store release compromised the ability of PNU120596 to increase intracellular calcium transients generated by α7 ligand activation. Spatiotemporal stochastic modeling of calcium transient responses corroborates these results and indicates that α7 receptor activation enables calcium microdomains locally and to lesser extent in the distant cytosol. From the model, allosteric modulation of the receptor activates CICR locally via ryanodine receptors and augments IICR through enhanced calcium influx due to prolonged α7 nAChR opening. These findings provide a new mechanistic framework for understanding the effect of α7 receptor allosteric modulation on both local and global calcium dynamics.


Assuntos
Cálcio/metabolismo , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Animais , Sinalização do Cálcio/efeitos dos fármacos , Sinalização do Cálcio/fisiologia , Linhagem Celular Tumoral , Citoplasma/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Humanos , Isoxazóis/farmacologia , Células PC12 , Compostos de Fenilureia/farmacologia , Ratos
17.
Int J Biol Macromol ; 107(Pt A): 290-296, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28870751

RESUMO

Protein gels with controlled viscoelastic properties could find numerous material and biomedical applications. Feather keratin is naturally abundant protein while its gelation property has not been explored. In this study hydrogel from fully reduced feather keratin was prepared by dialysis. The objectives of this work were to study the molecular mechanism of self-assembly of feather keratin gel and to characterize the structural and viscoelastic properties of hydrogels prepared under various pHs (3-9) and temperatures (50-90°C). Re-oxidation of free cysteine thiols and formation of hydrophobic interactions and hydrogen bond were determined as the main stabilizing forces in self-assembly of feather keratin gel. Adding thiol blocking agent of N-ethylmaleimide leads to reduced storage modulus of keratin gel; gelation was completely inhibited at 82% blockage of free thiols. Increasing temperature decreased storage modulus, while gelation at pH 3 resulted in stiffer gels compared to pHs of 5, 7 and 9. Feather keratin gels with tunable viscoelastic properties could find applications as engineered scaffolds for different tissues.


Assuntos
Plumas/química , Queratinas/química , Compostos de Sulfidrila/química , Substâncias Viscoelásticas/química , Animais , Galinhas , Cisteína/química , Etilmaleimida/farmacologia , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas/efeitos dos fármacos , Oxirredução/efeitos dos fármacos , Reologia/métodos , Temperatura
18.
Materials (Basel) ; 10(3)2017 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-28772674

RESUMO

Solvent-free copolymerization of epoxides derived from fatty esters of waste cooking oil with phthalic anhydride using (salen)CrIIICl as catalyst and n-Bu4NCl/DMAP (tetrabutylammonium chloride/4-(dimethylamino)pyridine) as co-catalysts was carried out for the first time under microwave irradiation, where reaction time was reduced from a number of hours to minutes. The polyesters were obtained with molecular weight (Mw = 3100-6750 g/mol) and dispersity values (D = 1.18-1.92) when (salen)CrIIICl/n-Bu4NCl was used as catalysts. Moreover, in the case of DMAP as a co-catalyst, polyesters with improved molecular weight (Mw = 5500-6950 g/mol) and narrow dispersity values (D = 1.07-1.28) were obtained even at reduced concentrations of (salen)CrIIICl and DMAP. The obtained products were characterized and evaluated by attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), proton nuclear magnetic resonance (¹H-NMR) spectroscopy, gel permeation chromatography (GPC), thermogravimetric analysis (TGA) and differential scanning calorimetric (DSC) Techniques.

19.
Chemosphere ; 163: 334-341, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27552693

RESUMO

Oil sands operations consume large volumes of water in bitumen extraction process and produce tailings that express pore water to the surface of tailings ponds known as oil sands process-affected water (OSPW). The OSPW is toxic and cannot be released into the environment without treatment. In addition to metals, dissolved solids, dissolved gases, hydrocarbons and polyaromatic compounds etc., OSPW also contains a complex mixture of dissolved organic acids, referred to as naphthenic acids (NAs). The NAs are highly toxic and react with metals to develop highly corrosive functionalities which cause corrosion in the oil sands processing and refining processes. We have chemically modified keratin biopolymer using polyhedral oligomeric silsesquioxanes (POSS) nanocages and goethite dopant to unfold keratinous structure for improving functionality. The untreated neat keratin and two modified sorbents were characterized to investigate structural, morphological, dimensional and thermal properties. These sorbents were then tested for the removal of NAs from OSPW. The NAs were selectively extracted and quantified before and after sorption process. The biosorption capacity (Q), rejection percentage (R%) and isotherm models were studied to investigate NAs removal efficiency of POSS modified keratin biopolymer (PMKB) and goethite modified keratin biopolymer (GMKB) from aliquots of OSPW.


Assuntos
Biopolímeros/química , Ácidos Carboxílicos/química , Hidrocarbonetos/química , Campos de Petróleo e Gás , Poluentes Químicos da Água/análise , Animais , Biomassa , Galinhas , Reagentes de Ligações Cruzadas/química , Plumas/química , Queratinas/química , Metais , Compostos de Organossilício/química , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Água/química , Difração de Raios X
20.
Artigo em Inglês | MEDLINE | ID: mdl-26989571

RESUMO

BACKGROUND: "Classic" stiff person syndrome (SPS) features stiffness, anti-glutamic acid decarboxylase (anti-GAD) antibodies, and other findings. Anti-GAD antibodies are also detected in some neurological syndromes (such as ataxia) in which stiffness is inconsistently present. Patients with otherwise "classic" SPS may either lack anti-GAD antibodies or be seropositive for others. Hence, SPS cases appear to fall within a clinical spectrum that includes conditions such as progressive encephalomyelitis with rigidity and myoclonus (PERM), which exhibits brainstem and autonomic features. We have compiled herein SPS-spectrum cases reported since 2010, and have segregated them on the basis of likely disease mechanism (autoimmune, paraneoplastic, or cryptogenic) for analysis. METHODS: The phrases "stiff person syndrome", "PERM", "anti-GAD antibody syndrome", and "glycine receptor antibody neurological disorders" were searched for in PubMed in January 2015. The results were narrowed to 72 citations after excluding non-English and duplicate reports. Clinical descriptions, laboratory data, management, and outcomes were categorized, tabulated, and analyzed. RESULTS: Sixty-nine autoimmune, 19 paraneoplastic, and 13 cryptogenic SPS-spectrum cases were identified. SPS was the predominant diagnosis among the groups. Roughly two-thirds of autoimmune and paraneoplastic cases were female. Anti-GAD antibodies were most frequently identified, followed by anti-amphiphysin among paraneoplastic cases and by anti-glycine receptor antibodies among autoimmune cases. Benzodiazepines were the most commonly used medications. Prognosis seemed best for cryptogenic cases; malignancy worsened that of paraneoplastic cases. DISCUSSION: Grouping SPS-spectrum cases by pathophysiology provided insights into work-up, treatment, and prognosis. Ample phenotypic and serologic variations are present within the categories. Ruling out malignancy and autoimmunity is appropriate for suspected SPS-spectrum cases.

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