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1.
Obstet Med ; 17(2): 108-111, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38784189

RESUMO

Maternal Graves' autoantibodies are well known to cause fetal and neonatal thyroid disturbances. Despite radioiodine therapy, Graves' autoantibodies are known to persist, which can cross the placenta and cause hyperthyroidism in the fetus. We present the case of a 26-year-old woman in her first pregnancy, clinically and biochemically euthyroid with history of treated Graves' disease, where the fetus showed signs of hyperthyroidism on antenatal scans. This was confirmed by amniotic fluid testing as fetal blood sampling was not feasible and successfully treated with maternal carbimazole whilst continuing thyroxine for the mother (block-replacement). We discuss the challenges in the diagnosis of fetal hyperthyroidism and treatment whilst maternal thyroid status is maintained on thyroxine.

2.
RSC Adv ; 13(31): 21345-21364, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37465579

RESUMO

The intricate, tightly controlled mechanism of wound healing that is a vital physiological mechanism is essential to maintaining the skin's natural barrier function. Numerous studies have focused on wound healing as it is a massive burden on the healthcare system. Wound repair is a complicated process with various cell types and microenvironment conditions. In wound healing studies, novel therapeutic approaches have been proposed to deliver an effective treatment. Nanoparticle-based materials are preferred due to their antibacterial activity, biocompatibility, and increased mechanical strength in wound healing. They can be divided into six main groups: metal NPs, ceramic NPs, polymer NPs, self-assembled NPs, composite NPs, and nanoparticle-loaded hydrogels. Each group shows several advantages and disadvantages, and which material will be used depends on the type, depth, and area of the wound. Better wound care/healing techniques are now possible, thanks to the development of wound healing strategies based on these materials, which mimic the extracellular matrix (ECM) microenvironment of the wound. Bearing this in mind, here we reviewed current studies on which NPs have been used in wound healing and how this strategy has become a key biotechnological procedure to treat skin infections and wounds.

3.
J Clin Neurophysiol ; 40(2): 180-186, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34510090

RESUMO

INTRODUCTION: This study aimed to determine the ability of multimodality intraoperative neurophysiologic monitoring, including somatosensory evoked potentials (SSEP) and EEG, to predict perioperative clinical stroke and stroke-related mortality after open-heart surgery in high-risk patients. METHODS: The records of all consecutive patients who underwent coronary artery bypass grafting, and cardiac valve repair/replacement with high risk for stroke who underwent both SSEP and EEG recording at the University of Pittsburgh Medical Center between 2009 and 2015 were reviewed. Sensitivity and specificity of these modalities to predict in-hospital clinical strokes and stroke-related mortality were calculated. RESULTS: A total of 531 patients underwent open cardiac procedures monitored using SSEP and EEG. One hundred thirty-one patients (24.67%) experienced significant changes in either modality. Fourteen patients (2.64%) suffered clinical strokes within 24 hours after surgery, and eight patients (1.50%) died during their hospitalization. The incidence of in-hospital clinical stroke and stroke-related mortality among patients who experienced a significant change in monitoring compared with those with no significant change was 11.45% versus 1.75%. The sensitivity and specificity of significant changes in either SSEP or EEG to predict in-hospital major stroke and stroke-related mortality were 0.93 and 0.77, respectively. CONCLUSIONS: Intraoperative neurophysiologic monitoring with SSEP and EEG has high sensitivity and specificity in predicting perioperative stroke and stroke-related mortality after open cardiac procedures. These results support the benefits of multimodality neuromonitoring during cardiac surgery.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Monitorização Neurofisiológica Intraoperatória , Acidente Vascular Cerebral , Humanos , Monitorização Neurofisiológica Intraoperatória/métodos , Potenciais Somatossensoriais Evocados/fisiologia , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/etiologia , Sensibilidade e Especificidade , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Estudos Retrospectivos
4.
J Racial Ethn Health Disparities ; 9(2): 691-697, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-33694125

RESUMO

BACKGROUND: Covid-19 toll is disproportionate in Blacks although the mechanisms remain incompletely understood. From a biological perspective, several host proteins have received most attention as logical susceptibility targets. Specifically, angiotensin-converting enzyme 2 (ACE2) serves as the epithelial cell receptor and acts in concert with transmembrane protease serine 2 (TMPRSS2). Intriguingly, ACE2 can also suppress the inflammatory response and therefore may impact the severity of Covid-19 infections (from the exuberant immune response a.k.a. "cytokine storm"). We, therefore, assessed expression of ACE2 and TMPRSS2 in Blacks versus Whites. METHODS: Archived mucosal biopsies from colonoscopic biopsies of visually normal rectal mucosa without concurrent neoplasia or inflammation were used for this study. Total mRNA was isolated and subjected to real-time polymerase chain reaction for ACE2, and TMPRSS2 was assessed from non-Hispanic Blacks (n = 45) and non-Hispanic Whites (n = 38). GAPDH and beta-actin were used for normalization. Multivariable analysis was performed using Analyse-IT software. RESULTS: ACE2 and TMPRSS2 levels were not altered by gender, BMI, or age. ACE2 levels were lower in Blacks than Whites achieving statistical significance in multivariable (0.51-fold, p = 0.03) but not quite in univariable (p = 0.07) analysis. This downregulation was mirrored in TMRPSS2 in both univariable (p = 0.03) and multivariable analyses (0.41-fold, p = 0.02). Moreover, there was a strong correlation between ACE2 and TMPRSS2 levels (r-squared = 0.78). CONCLUSIONS: To our knowledge, this is the first report on racial differences inACE2 and TMPRSS2 mucosal expression. This may provide potential biological underpinnings for the disproportionately higher mortality of Covid-19 in Blacks and should spur future studies.


Assuntos
Enzima de Conversão de Angiotensina 2 , COVID-19 , Negro ou Afro-Americano , Enzima de Conversão de Angiotensina 2/genética , Humanos , Inflamação , SARS-CoV-2
5.
Therap Adv Gastroenterol ; 14: 17562848211064080, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34987609

RESUMO

The diagnosis and therapy of Helicobacter pylori infection have undergone major changes based on the use the principles of antimicrobial stewardship and increased availability of susceptibility profiling. H. pylori gastritis now recognized as an infectious disease, as such there is no placebo response allowing outcome to be assessed in relation to the theoretically obtainable cure rate of 100%. The recent recognition of H. pylori as an infectious disease has changed the focus to therapies optimized to reliably achieve high cure rates. Increasing antimicrobial resistance has also led to restriction of clarithromycin, levofloxacin, or metronidazole to susceptibility-based therapies. Covid-19 resulted in the almost universal availability of polymerase chain reaction testing in hospitals which can be repurposed to utilize readily available kits to provide rapid and inexpensive detection of clarithromycin resistance. In the United States, major diagnostic laboratories now offer H. pylori culture and susceptibility testing and American Molecular Laboratories offers next-generation sequencing susceptibility profiling of gastric biopsies or stools for the six commonly used antibiotics without need for endoscopy. Current treatment recommendations include (a) only use therapies that are reliably highly effective locally, (b) always perform a test-of-cure, and (c) use that data to confirm local effectiveness and share the results to inform the community regarding which therapies are effective and which are not. Empiric therapy should be restricted to those proven highly effective locally. The most common choices are 14-day bismuth quadruple therapy and rifabutin triple therapy. Prior guidelines and treatment recommendations should only be used if proven locally highly effective.

6.
Neurologist ; 25(5): 113-116, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32925480

RESUMO

BACKGROUND: Coronary artery bypass grafting (CABG) is a proven approach in the treatment of coronary heart disease, but the surgery has several complications, including stroke and death. Though it has been established that perioperative stroke is associated with higher rates of long-term mortality, the relationship between stroke and mortality in the perioperative period has not yet been systematically examined. METHODS: Online databases of peer-reviewed literature were searched to retrieve articles concerning mortality and stroke after CABG in patients with carotid stenosis. Six studies (n=3786) were included for analysis. This study was conducted at a single University hospital system, University of Pittsburgh Medical Center, on patients who underwent CABG. The data obtained from peer-reviewed literature originated from several sources, primarily single institution hospitals. RESULTS: Consistent with current literature, the incidence of stroke in CABG patients with significant carotid stenosis was 2.1%. Data were further analyzed to generate a summary odds ratio of stroke-related mortality after CABG, which showed that patients who died within 30 days of CABG were 7.3 times more likely to have had a perioperative stroke (95% confidence interval, 4.1-13.2). The 30-day mortality rate among perioperative stroke victims was 14.4% versus 2.3% for nonstroke patients. CONCLUSIONS: Together, these data suggest an association between stroke and mortality in the perioperative period in patients undergoing CABG, demonstrating a need for improved monitoring, screening, and treatment of stroke before, during, and shortly after surgery.


Assuntos
Estenose das Carótidas/cirurgia , Ponte de Artéria Coronária , Complicações Pós-Operatórias , Acidente Vascular Cerebral , Ponte de Artéria Coronária/efeitos adversos , Ponte de Artéria Coronária/mortalidade , Humanos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/mortalidade , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/mortalidade
7.
Parasitology ; 146(11): 1451-1461, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31104638

RESUMO

The present work aims to explore the mechanism of action of C-cinnamoyl glycoside as an antifilarial agent against the bovine filarial nematode Setaria cervi. Both apoptosis and autophagy programmed cell death pathways play a significant role in parasitic death. The generation of reactive oxygen species, alteration of the level of antioxidant components and disruption of mitochondrial membrane potential may be the causative factors that drive the parasitic death. Monitoring of autophagic flux via the formation of autophagosome and autophagolysosome was detected via CYTO ID dye. The expression profiling of both apoptotic and autophagic marker proteins strongly support the initial findings of these two cell death processes. The increased interaction of pro-autophagic protein Beclin1 with BCL-2 may promote apoptotic pathway by suppressing anti-apoptotic protein BCL-2 from its function. This in turn partially restrains the autophagic pathway by engaging Beclin1 in the complex. But overall positive increment in autophagic flux was observed. Dynamic interaction and regulative balance of these two critical cellular pathways play a decisive role in controlling disease pathogenesis. Therefore, the present experimental work may prosper the chance for C-cinnamoyl glycosides to become a potential antifilarial therapeutic in the upcoming day after detail in vivo study and proper clinical trial.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Filaricidas/farmacologia , Glicosídeos/farmacologia , Setaria (Nematoide)/efeitos dos fármacos , Wuchereria bancrofti/efeitos dos fármacos , Animais , Setaria (Nematoide)/fisiologia , Wuchereria bancrofti/fisiologia
8.
ACS Omega ; 3(8): 10145-10153, 2018 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-30221241

RESUMO

A newly designed cyanide-selective chemosensor based on chromone containing benzothiazole groups [3-(2,3-dihydro-benzothiazol-2-yl)-chromen-4-one (DBTC)] was synthesized and structurally characterized by physico-chemical, spectroscopic, and single-crystal X-ray diffraction analyses. The compound DBTC can detect cyanide anions based on nucleophilic addition as low as 5.76 nM in dimethyl sulfoxide-N-(2-hydroxyethyl)piperazine-N'-ethanesulfonic acid buffer (20 mM, pH 7.4) (v/v = 1:3). The binding mode between receptor DBTC and cyanide nucleophile has also been demonstrated by experimental studies using various spectroscopic tools and theoretical studies, and the experimental work has also been verified by characterizing one supporting compound of similar probable structure of the final product formed between DBTC and cyanide ion (DBTC-CN compound) by single-crystal X-ray analysis for detailed structural analyses. In theoretical study, density functional theory procedures have been used to calculate the molecular structure and the calculation of the Fukui function for evaluation of the electrophilic properties of each individual acceptor atom. Furthermore, the efficacy of the probe (DBTC) to detect the distribution of CN- ions in living cells has been checked by acquiring the fluorescence image using a confocal microscope. Notably, the paper strips with DBTC were prepared, and these could serve as efficient and suitable CN- test kits successfully.

9.
Neoplasia ; 20(3): 289-294, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29471289

RESUMO

The biological underpinnings for racial disparities in colorectal cancer (CRC) incidence remain to be elucidated. We have previously reported that the cohesin SA-1 down-regulation is an early event in colon carcinogenesis which is dramatically accentuated in African-Americans. In order to investigate the mechanism, we evaluated single nucleotide polymorphisms (SNPs) for association with SA-1-related outcomes followed by gene editing of candidate SNP. We observed that rs34149860 SNP was significantly associated with a lower colonic mucosal SA-1 expression and evaluation of public databases showed striking racial discordance. Given that the predicted SNP would alter miR-29b binding site, we used CRISPR knock-in in CRC cells and demonstrated that the SNP but not wild-type had profound alterations in SA-1 expression with miR-29b inhibitor. This is the first demonstration of high-order chromatin regulators as a modulator of racial differences, risk alteration with SNPs and finally specific modulation by microRNAs.


Assuntos
Proteínas de Ciclo Celular/genética , Proteínas Cromossômicas não Histona/genética , Neoplasias Colorretais/genética , Regulação para Baixo/genética , Proteínas Nucleares/genética , Polimorfismo de Nucleotídeo Único/genética , Sítios de Ligação/genética , Carcinogênese/genética , Linhagem Celular Tumoral , Predisposição Genética para Doença/genética , Células HCT116 , Humanos , MicroRNAs/genética , Coesinas
10.
Anal Chem ; 90(4): 2933-2938, 2018 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-29353475

RESUMO

A lysosome-targetable fluorogenic probe, LysoFP-NO2, was designed and synthesized based on a naphthalimide fluorophore that can detect selectively carbon monoxide (CO) in HEPES buffer (pH 7.4, 37 °C) through the transformation of the nitro group into an amino-functionalized system in the presence of CO. LysoFP-NO2 triggered a "turn-on" fluorescence response to CO with a simultaneous increase of fluorescence intensity by more than 75 times. The response is selective over a variety of relevant reactive nitrogen, oxygen, and sulfur species. Also, the probe is an efficient candidate for monitoring changes in intracellular CO in living cells (MCF7), and the fluorescence signals specifically localize in the lysosome compartment.


Assuntos
Monóxido de Carbono/análise , Corantes Fluorescentes/química , Lisossomos/química , Sobrevivência Celular , Corantes Fluorescentes/síntese química , Humanos , Células MCF-7 , Estrutura Molecular , Naftalimidas/química , Dióxido de Nitrogênio/química , Imagem Óptica , Espectrometria de Fluorescência
12.
Eur J Med Chem ; 143: 598-610, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29207343

RESUMO

A series of novel carbamo(dithioperoxo)thioate derivatives have been prepared in excellent yield using a significantly fast, one-pot three component reaction and experimented for their potential as anti-filarial agents against model filarial nematode Setaria cervi. Among 23 compounds (4a-w) evaluated for the anti-filarial activities, five compounds (4a, 4b, 4c, 4d and 4h) have shown promising anti-proliferative effects on the juvenile stage microfilariae (mf) as well as in adults in a time and dose dependent manner. Compound 4a was found most active against oocytes, mf and adult nematods as well as non-cytotoxic to the normal cells. It has been established that the anti-filarial activity of the compounds were observed due to the involvement of reactive oxygen species (ROS) and apoptosis. Several biochemical and microscopic experiments have been carried out to establish the fact that both intrinsic and extrinsic pathways of apoptosis contribute to the compound 4a mediated death phenomenon of the filarial nematodes.


Assuntos
Filarioidea/efeitos dos fármacos , Compostos de Sulfidrila/farmacologia , Animais , Apoptose/efeitos dos fármacos , Relação Dose-Resposta a Droga , Estrutura Molecular , Oócitos/efeitos dos fármacos , Relação Quantitativa Estrutura-Atividade , Espécies Reativas de Oxigênio/metabolismo , Compostos de Sulfidrila/síntese química , Compostos de Sulfidrila/química
13.
Colloids Surf B Biointerfaces ; 161: 236-243, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29080508

RESUMO

The present work seeks to explore the antifilarial activity of biopolymer functionalized gold nanoparticles (AuNPs) against human filarial parasite (Wuchereria bancrofti) through Nrf2 signaling for the first time. A natural polymer, chitosan is used along with Terminalia chebula extract to synthesize AuNPs following the principles of green chemistry. The probable mode of action of AuNPs as filaricidal agent has been investigated in detail using model filarial parasite, Setaria cervi (bovine parasite). Biopolymers inspired AuNPs exhibit superior antifilarial activity against both human and bovine filarial parasites, and are able to induce oxidative stress and apoptotic cell death in filarial parasites mediated through mitochondria. AuNPs also alter the Nrf2 signaling. In addition, the synthesized nanomaterials appear to be nontoxic to mammalian system. Thus the present mechanistic study, targeting human filarial parasites, has the potential to increase the therapeutic prospects of AuNPs to control lymphatic filariasis in the upcoming days.


Assuntos
Filaricidas/química , Ouro/química , Nanopartículas Metálicas/química , Nanomedicina/métodos , Animais , Apoptose/efeitos dos fármacos , Bovinos , Quitosana/química , Filariose/tratamento farmacológico , Filariose/parasitologia , Filaricidas/administração & dosagem , Ouro/administração & dosagem , Humanos , Nanopartículas Metálicas/administração & dosagem , Extratos Vegetais/química , Ratos Wistar , Setaria (Nematoide)/efeitos dos fármacos , Setaria (Nematoide)/fisiologia , Terminalia/química , Wuchereria bancrofti/efeitos dos fármacos , Wuchereria bancrofti/fisiologia
14.
Carbohydr Polym ; 157: 1666-1676, 2017 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-27987881

RESUMO

The gold nanoparticles (AuNPs) have been synthesized biogenically by using black pepper (Piper nigrum) extract according to the principles of green chemistry in presence and absence of a biopolymer, chitosan. A comprehensive study (up to cellular level) on the antifilarial (against Setaria cervi) activity of AuNPs has been made for the first time with a view to use it clinically. The bioactivity of biopolymer capped biogenic AuNP increases significantly compared to simple biogenic AuNP. The biopolymer plays an important role in inspiring AuNP through its inherent positive charges and hydrophobicity. The developed nanomaterial boosts the production of ROS (reactive oxygen species) and misbalances the antioxidant parameters of parasites such as GSH, GST, GPx, SOD and catalase. The produced ROS ultimately induces oxidative stress, which leads to apoptotic cell death in filarial worms. The synthesized nanomaterials exhibit negligible toxicity towards human PBMCs. The present study may serve as a fruitful platform to explore biopolymer capped gold nanoparticles as efficient antifilarial therapeutics.


Assuntos
Anti-Helmínticos/farmacologia , Quitosana , Ouro , Nanopartículas Metálicas , Setaria (Nematoide)/efeitos dos fármacos , Animais , Biopolímeros , Células Cultivadas , Fragmentação do DNA , Humanos
15.
Curr Drug Metab ; 17(10): 937-970, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27719626

RESUMO

BACKGROUND: Human diseases caused by the infectious parasites have been one of the major problems throughout the evolutionary journey. Protozoan and metazoan parasitic infections result in a large number of deaths, disabilities and socio-economic loss worldwide to date. Despite the best efforts for developing suitable antiparasitics, these infections take a massive toll on human health. The prevalence of emerging resistance to the existing drugs, lack of efficacy and toxic side effects are as added complications. Being enlisted under 'neglected' category, serious diseases like leishmaniasis, filariasis, trypanosomiasis etc. have failed to draw attention of the governments as well as the pharmaceutical companies. Thus, target specific as well as cost-convenient therapy needs to be employed for the treatment of these diseases and selective targeting of metabolic pathways appears to be the most promising mean. METHODS: In this context, quality works have been explored for screening either anti-metabolic drugs or selective targets in different groups of parasites. Moreover, complete genome sequencing and metabolomic profiling have provided the initiatives to search for new lethal targets in parasites. RESULTS: New metabolic targets are being reported from different organelles and other sub-cellular compartments of parasites such as mitochondrion, kinetoplast, apicoplast, glycosome, hydrogenosome, acidocalcisome, plasma membrane, cytoskeleton, etc. Herein, unique findings achieved in identifying new antimetabolic drugs or targets and studying their molecular mode of actions have been reviewed by incorporating existing and upcoming approaches. CONCLUSION: Considering the alarming scenario of diseases caused by parasites globally, this paper provides a comprehensive review to the scientific community on the development of novel interventions based on metabolic targets to combat the challenges posed by parasites.


Assuntos
Antiparasitários/farmacologia , Antiparasitários/uso terapêutico , Redes e Vias Metabólicas/efeitos dos fármacos , Parasitos/efeitos dos fármacos , Doenças Parasitárias/tratamento farmacológico , Animais , Antiparasitários/farmacocinética , Desenho de Fármacos , Inibidores Enzimáticos/farmacocinética , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Humanos , Metaboloma , Parasitos/metabolismo
16.
Eur J Med Chem ; 114: 308-17, 2016 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-27015610

RESUMO

A series of C-cinnamoyl glycosides has been synthesized in good yield by the BF3·OEt2 catalyzed aldol condensation of C-glycosylated acetone derivative with a variety of aromatic aldehydes. The synthesized compounds were evaluated for their potential as anti-filarial agents against bovine filarial parasite Setaria cervi and human filariid Wuchereria bancrofti using a number of biological assays such as relative movability (RM) assessment and MTT reduction assay. Among twenty seven test compounds six compounds were found active in terms of MIC, IC50 and LC50 values. Further biological studies were carried out using three lead compounds because of their significantly low MIC values and IC50 values compared to the standard anti-filarial drug Ivermectin. In addition, structure activity relationship study of the test compounds has been carried out using 3D-QSAR analysis.


Assuntos
Filariose/tratamento farmacológico , Filarioidea/efeitos dos fármacos , Glicosídeos/farmacologia , Animais , Bovinos , Relação Dose-Resposta a Droga , Glicosídeos/síntese química , Glicosídeos/química , Humanos , Estrutura Molecular , Relação Quantitativa Estrutura-Atividade
17.
Mini Rev Med Chem ; 16(17): 1415-1441, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26586122

RESUMO

Ailments caused by helminth parasites are global causing different types of clinical complications with permanent and long term morbidity in humans. Although huge advances have been made in medical sciences the effectiveness of available anthelmintics are still quite limited. Starting from the 50's, most importance was given to synthetic compounds for developing remedies from them, however, the traditional knowledge of medicine of different countries continued to provide us clues against this widespread health problem. Natural products or structural analogs with diverse structures are always been the major sources for discovering new therapeutics and in recent past different active compounds have also been identified form these plant sources having anthelmintic properties. Although compounds of diverse chemical nature and classes were identified, most active ones belong to either phenol or terpene in broad chemical nature. The mechanism of action of these phytotherapeutics is usually multi-targeted and can act against the helminth parasites through diverse spectrum of activities. In this review we summarized the effective anthelmintics belong to either phenolics or terpenoids and highlighted the major way of their effectiveness. This also highlights the recent development of new therapeutic strategies against helminth parasites in the light of recent advances of knowledge. In addition, developing efficient strategies to promote apoptosis and disturbing redox status in them by natural products can provide us a clue in antifilarial drug developmental research and crucial unmet medical need.


Assuntos
Anti-Helmínticos/química , Polifenóis/química , Terpenos/química , Animais , Anti-Helmínticos/farmacologia , Benzimidazóis/química , Benzimidazóis/farmacologia , Resistência a Medicamentos , Helmintos/efeitos dos fármacos , Lactonas/química , Lactonas/farmacologia , Agonistas Nicotínicos/química , Agonistas Nicotínicos/farmacologia , Polifenóis/farmacologia , Relação Estrutura-Atividade , Taninos/química , Taninos/farmacologia , Terpenos/farmacologia
18.
Exp Parasitol ; 160: 39-48, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26627139

RESUMO

Green synthesis of silver nanomaterial plays a pivotal role in the growing field of nanotechnology. Development of anti-parasitic drugs from plant metabolites has been in regular practice from the ancient period but most of them were discarded due to their inefficiency to control diseases effectively. At present, nanoparticles are used for developing anti-parasitic therapy for their unique properties such as smallest in size, bio-ability, bio-compatibility and penetration capacity into a cell. The present study aims at synthesis of silver nanoparticles (AgNPs) by using funicles extract of Acacia auriculiformis and tests its efficacy as antifilarial. Experimental evidence show that AgNPs are effective at a very low concentration compared to crude plant extracts. Synthesis of these nanoparticles is a single-step, biogenic, cost effective and eco-friendly process. Synthesized nanoparticles were characterized by UV-Vis spectroscopy, TEM, SAED, FTIR, EDX, FESEM and Z-potential. The antifilarial efficacy of AgNPs was tested against different life cycle stages of bovine filarial parasite Setaria cervi by morphological study, motility assessment and viability assay. These nanoparticles are found to have antifilarial activity with LC50 of 5.61 µg/mL and LC90 of 15.54 µg/mL against microfilaria of S. cervi. The microscopic findings and the detailed molecular studies confirmed that green synthesized AgNPs were effective enough to induce apoptosis through up regulation of ROS (reactive oxygen species).


Assuntos
Acacia/química , Apoptose/efeitos dos fármacos , Nanopartículas Metálicas/efeitos adversos , Espécies Reativas de Oxigênio/metabolismo , Setaria (Nematoide)/efeitos dos fármacos , Animais , Apoptose/fisiologia , Bovinos , Fragmentação do DNA , DNA de Helmintos/química , DNA de Helmintos/genética , Feminino , Marcação In Situ das Extremidades Cortadas , Macrófagos Peritoneais/efeitos dos fármacos , Masculino , Nanopartículas Metálicas/administração & dosagem , Nanopartículas Metálicas/toxicidade , Microscopia Eletrônica de Varredura , Espectroscopia Fotoeletrônica , Extratos Vegetais/química , Ratos , Ratos Wistar , Setaria (Nematoide)/citologia , Setaria (Nematoide)/genética , Setaria (Nematoide)/metabolismo , Setaríase/parasitologia , Prata , Espectroscopia de Infravermelho com Transformada de Fourier , Regulação para Cima
19.
Carbohydr Polym ; 137: 390-401, 2016 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-26686143

RESUMO

The carbohydrate polymer inspired silver nanoparticles (AgNPs) are designed and synthesized through ultrasound assisted green process using unique combination of a biomolecule (tyrosine) and a natural polymer (starch). A comprehensive mechanistic study on the reactive oxygen species (ROS) mediated filaricidal (against Setaria cervi) and mosquitocidal (against second and fourth instar larvae of Culex quinquefasciatus) activities of AgNPs has been made for the first time for controlling filariasis by taking care of both filariid and its vector. The mechanism may help in formulating antifilarial drug based on carbohydrate polymer inspired AgNPs. The role of carbohydrate polymer in inspiring bioactivity of AgNPs has been looked into and its activities have been compared with the commercially available AgNPs. Cytotoxicity of AgNPs on macrophages of Wistar rat has been evaluated to ensure its selectivity towards filariid and larvae.


Assuntos
Inseticidas/química , Inseticidas/farmacologia , Nanopartículas Metálicas/química , Polímeros/química , Polímeros/farmacologia , Prata/química , Aedes/efeitos dos fármacos , Animais , Culex/efeitos dos fármacos , Inseticidas/efeitos adversos , Macrófagos/efeitos dos fármacos , Polímeros/efeitos adversos , Ratos , Ratos Wistar
20.
Brain Struct Funct ; 221(4): 1939-53, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-25716298

RESUMO

In utero exposure of rats to nicotine (NIC) provides a useful animal model for studying the impact of smoking during pregnancy on human offspring. Certain sequelae of prenatal NIC exposure suggest an impact on the development of the midbrain dopamine (DA) system, which receives a robust cholinergic innervation from the mesopontine tegmentum. We therefore investigated whether prenatal NIC induced structural changes in cells and synapses within the midbrain that persisted into adulthood. Osmotic minipumps delivering either sodium bitartrate (vehicle; VEH) or NIC bitartrate at 2 mg/kg/day were implanted into nine timed-pregnant dams at E4. At birth, rat pups were culled to litters of six males each, and the litters were cross-fostered. Plasma levels of NIC and cotinine from killed pups provided evidence of NIC exposure in utero. Pups separated from dams at weaning showed a trend toward reduced locomotor activity at this time point but not when tested again in adulthood. Adult rats were killed for anatomical studies. Estimates of brain size and volume did not vary with NIC treatment. Midbrain sections stained for Nissl or by immunoperoxidase for tyrosine hydroxylase and analyzed using unbiased stereology revealed no changes in volume or cell number in the substantia nigra compacta or ventral tegmental area as a result of NIC exposure. Within the ventral tegmental area, electron microscopic physical disector analysis showed no significant differences in the number of axon terminals or the number of asymmetric (putative excitatory) or symmetric (putative inhibitory) synapses. Although too infrequent to estimate by unbiased stereology, no obvious difference in the proportion of cholinergic axons was noted in NIC- versus VEH-treated animals. These data suggest that activation of nicotinic receptors during prenatal development induces no significant modifications in the structure of cells in the ventral midbrain when assessed in adulthood.


Assuntos
Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/ultraestrutura , Mesencéfalo/efeitos dos fármacos , Mesencéfalo/ultraestrutura , Nicotina/administração & dosagem , Efeitos Tardios da Exposição Pré-Natal/patologia , Animais , Axônios/efeitos dos fármacos , Axônios/patologia , Axônios/ultraestrutura , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Encéfalo/ultraestrutura , Cotinina/sangue , Dopamina/metabolismo , Neurônios Dopaminérgicos/patologia , Feminino , Locomoção/efeitos dos fármacos , Masculino , Mesencéfalo/patologia , Nicotina/sangue , Parte Compacta da Substância Negra/efeitos dos fármacos , Parte Compacta da Substância Negra/patologia , Parte Compacta da Substância Negra/ultraestrutura , Gravidez , Ratos , Sinapses/efeitos dos fármacos , Sinapses/patologia , Sinapses/ultraestrutura , Tirosina 3-Mono-Oxigenase/metabolismo , Área Tegmentar Ventral/efeitos dos fármacos , Área Tegmentar Ventral/patologia , Área Tegmentar Ventral/ultraestrutura
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