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2.
Sci Rep ; 12(1): 12414, 2022 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-35858932

RESUMO

The iron impregnated fungal bio-filter (IIFB) discs of luffa sponge containing Phanerochaete chrysosporium mycelia have been used for the removal of As(III) from water. Two different forms of same biomass viz. free fungal biomass (FFB) and modified free fungal biomass (chemically modified and iron impregnated; CFB and IIFB) have been simultaneously investigated to compare the performance of immobilization, chemo-tailoring and iron impregnation for remediation of As(III). IIFB showed highest uptake capacity and percentage removal of As(III), 1.32 mg/g and 92.4% respectively among FFB, CFB and IIFB. Further, the application of RSM and ANN-GA based mathematical model showed a substantial increase in removal i.e. 99.2% of As(III) was filtered out from water at optimised conditions i.e. biomass dose 0.72 g/L, pH 7.31, temperature 42 °C, and initial As(III) concentration 1.1 mg/L. Isotherm, kinetic and thermodynamic studies proved that the process followed monolayer sorption pattern in spontaneous and endothermic way through pseudo-second order kinetic pathway. Continuous mode of As(III) removal in IIFB packed bed bioreactor, revealed increased removal of As(III) from 76.40 to 88.23% with increased column height from 5 to 25 cm whereas the removal decreased from 88.23 to 69.45% while increasing flow rate from 1.66 to 8.30 mL/min. Moreover, the IIFB discs was regenerated by using 10% NaOH as eluting agent and evaluated for As(III) removal for four sorption-desorption cycles, showing slight decrease of their efficiency by 1-2%. SEM-EDX, pHzpc, and FTIR analysis, revealed the involvement of hydroxyl and amino surface groups following a non-electrostatic legend exchange sorption mechanism during removal of As(III).


Assuntos
Poluentes Químicos da Água , Purificação da Água , Adsorção , Biomassa , Concentração de Íons de Hidrogênio , Ferro , Cinética , Termodinâmica , Água , Poluentes Químicos da Água/metabolismo
3.
Mymensingh Med J ; 31(1): 200-207, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34999703

RESUMO

The COVID-19 pandemic has turned into a global calamity and affected millions of lives around the world. Even though the vaccination efforts have started, they are yet to have an effective impact on the lower to middle-income countries. Early detection and isolation are still the best way to control the spread of the virus. The standard practice for detecting COVID-19 is the RT-PCR (Reverse Transcription Polymerase Chain Reaction) test but this test has a high probability of producing false-negative results plus lack of availability at all the time due to shortage of kit. Since COVID-19 is a respiratory disease affecting the lungs and the imaging patterns caused by COVID-19 can be observed in chest HRCT (High Resolution Computed Tomography) scans. As a result, HRCT can be used as an alternative diagnostic modality for any suspected cases of COVID-19. In this cross-sectional study was carried out in the Department of Radiology and Imaging, BSMMU, Dhaka, Bangladesh from May 12, 2020 to August 10, 2020. Chest HRCT scans of 284 suspected patients irrespective of age and sex who had done RT-PCR test either positive or negative test result having symptoms suggesting COVID pneumonia were enrolled in this study. Patients who had not done RT-PCR and who were not willing to do HRCT chest were excluded. According to the study, ground glass opacity is the most common feature and found in 89.44% of patients. The other predominant features were including consolidation, crazy paving, fibrotic density and vascular enlargement. The diagnostic performance of the CT scan was also evaluated using the RT-PCR test result as the gold standard and the sensitivity, specificity, and accuracy of the CT scan diagnosis were found to be 83.2%, 50% and 79.9% respectively. The severity of the five lung lobes has also been studied. The right middle lobe and the left upper lobe seemed to be in more severe condition for most of the patients compared to the other lung lobes.


Assuntos
COVID-19 , Bangladesh , Estudos Transversais , Humanos , Pulmão/diagnóstico por imagem , Pandemias , Reação em Cadeia da Polimerase Via Transcriptase Reversa , SARS-CoV-2 , Centros de Atenção Terciária , Tomografia Computadorizada por Raios X
4.
Mymensingh Med J ; 30(3): 850-854, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34226479

RESUMO

Angiomyolipomas (AML) are benign tumor of kidney also referred as renal hamartoma composed of varying amounts of mature adipose tissue, smooth muscle, and blood vessels. It is seen in two distinct clinical forms, a sporadic (isolated) form and 55-80% seen in association with Tuberous sclerosis complex (TSC). If the lesion grows to a large size, a series of clinical manifestations and serious complications may occur. Here we present a case of 26 years lady who presented in the Department Radiology & Imaging of Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh with chief complaints of bilateral loin pain and occasional hematuria for 2 months. Ultrasound abdomen and contrast enhanced computed tomography shows bilateral renal angiomyolipoma (left>right). In order to look for tuberous sclerosis features, we followed her with plain computed tomography of head which shows subependymal calcifications.


Assuntos
Angiomiolipoma , Neoplasias Renais , Esclerose Tuberosa , Angiomiolipoma/diagnóstico por imagem , Bangladesh , Feminino , Humanos , Rim , Neoplasias Renais/diagnóstico por imagem , Esclerose Tuberosa/diagnóstico , Esclerose Tuberosa/diagnóstico por imagem
5.
Mater Today Chem ; 20: 100443, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33615086

RESUMO

The World Health Organization (WHO) has declared the COVID-19 an international health emergency due to the severity of infection progression, which became more severe due to its continuous spread globally and the unavailability of appropriate therapy and diagnostics systems. Thus, there is a need for efficient devices to detect SARS-CoV-2 infection at an early stage. Nowadays, the reverse transcription polymerase chain reaction (RT-PCR) technique is being applied for detecting this virus around the globe; however, factors such as stringent expertise, long diagnostic times, invasive and painful screening, and high costs have restricted the use of RT-PCR methods for rapid diagnostics. Therefore, the development of cost-effective, portable, sensitive, prompt and selective sensing systems to detect SARS-CoV-2 in biofluids at fM/pM/nM concentrations would be a breakthrough in diagnostics. Immunosensors that show increased specificity and sensitivity are considerably fast and do not imply costly reagents or instruments, reducing the cost for COVID-19 detection. The current developments in immunosensors perhaps signify the most significant opportunity for a rapid assay to detect COVID-19, without the need of highly skilled professionals and specialized tools to interpret results. Artificial intelligence (AI) and the Internet of Medical Things (IoMT) can also be equipped with this immunosensing approach to investigate useful networking through database management, sharing, and analytics to prevent and manage COVID-19. Herein, we represent the collective concepts of biomarker-based immunosensors along with AI and IoMT as smart sensing strategies with bioinformatics approach to monitor non-invasive early stage SARS-CoV-2 development, with fast point-of-care (POC) diagnostics as the crucial goal. This approach should be implemented quickly and verified practicality for clinical samples before being set in the present times for mass-diagnostic research.

6.
Anaesthesia ; 76(3): 312-319, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33073371

RESUMO

At the onset of the global pandemic of COVID-19 (SARS-CoV-2), guidelines recommended using regional anaesthesia for caesarean section in preference to general anaesthesia. National figures from the UK suggest that 8.75% of over 170,000 caesarean sections are performed under general anaesthetic. We explored whether general anaesthesia rates for caesarean section changed during the peak of the pandemic across six maternity units in the north-west of England. We analysed anaesthetic information for 2480 caesarean sections across six maternity units from 1 April to 1 July 2020 (during the pandemic) and compared this information with data from 2555 caesarean sections performed at the same hospitals over a similar period in 2019. Primary outcome was change in general anaesthesia rate for caesarean section. Secondary outcomes included overall caesarean section rates, obstetric indications for caesarean section and regional to general anaesthesia conversion rates. A significant reduction (7.7 to 3.7%, p < 0.0001) in general anaesthetic rates, risk ratio (95%CI) 0.50 (0.39-0.93), was noted across hospitals during the pandemic. Regional to general anaesthesia conversion rates reduced (1.7 to 0.8%, p = 0.012), risk ratio (95%CI) 0.50 (0.29-0.86). Obstetric indications for caesarean sections did not change (p = 0.17) while the overall caesarean section rate increased (28.3 to 29.7%), risk ratio (95%CI) 1.02 (1.00-1.04), p = 0.052. Our analysis shows that general anaesthesia rates for caesarean section declined during the peak of the pandemic. Anaesthetic decision-making, recommendations from anaesthetic guidelines and presence of an on-site anaesthetic consultant in the delivery suite seem to be the key factors that influenced this decline.


Assuntos
Anestesia Geral/estatística & dados numéricos , Anestesia Obstétrica/estatística & dados numéricos , COVID-19/epidemiologia , Cesárea/estatística & dados numéricos , Estudos Transversais , Inglaterra/epidemiologia , Feminino , Humanos , Gravidez , Estudos Retrospectivos , SARS-CoV-2
7.
J Dent Res ; 100(2): 187-193, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33138663

RESUMO

Understanding the pathophysiology of the coronavirus disease 2019 (COVID-19) infection remains a significant challenge of our times. The gingival crevicular fluid being representative of systemic status and having a proven track record of detecting viruses and biomarkers forms a logical basis for evaluating the presence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The study aimed to assess gingival crevicular fluid (GCF) for evidence of SARS-CoV-2 in 33 patients who were deemed to be COVID-19 positive upon nasopharyngeal sampling. An attempt was also made to comparatively evaluate it with saliva in terms of its sensitivity, as a diagnostic fluid for SARS-CoV-2. GCF and saliva samples were collected from 33 COVID-19-confirmed patients. Total RNA was extracted using NucliSENS easyMAG (bioMérieux) and eluted in the elution buffer. Envelope gene (E gene) of SARS-CoV-2 and human RNase P gene as internal control were detected in GCF samples by using the TRUPCR SARS-CoV-2 RT qPCR kit V-2.0 (I) in an Applied Biosystems 7500 real-time machine. A significant majority of both asymptomatic and mildly symptomatic patients exhibited the presence of the novel coronavirus in their GCF samples. Considering the presence of SARS-CoV-2 RNA in the nasopharyngeal swab sampling as gold standard, the sensitivity of GCF and saliva, respectively, was 63.64% (confidence interval [CI], 45.1% to 79.60%) and 64.52% (CI, 45.37% to 80.77%). GCF was found to be comparable to saliva in terms of its sensitivity to detect SARS-CoV-2. Saliva samples tested positive in 3 of the 12 patients whose GCF tested negative, and likewise GCF tested positive for 2 of the 11 patients whose saliva tested negative on real-time reverse transcription polymerase chain reaction. The results establish GCF as a possible mode of transmission of SARS-CoV-2, which is the first such report in the literature, and also provide the first quantifiable evidence pointing toward a link between the COVID-19 infection and oral health.


Assuntos
COVID-19/diagnóstico , Líquido do Sulco Gengival/virologia , SARS-CoV-2/isolamento & purificação , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Saliva/virologia , Adulto Jovem
8.
Int J Tuberc Lung Dis ; 23(12): 1257-1262, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31931908

RESUMO

SETTING: Patients with presumed multidrug-resistant tuberculosis (MDR-TB) and undergoing MDR-TB treatment from Rajasthan, India.OBJECTIVE: To compare the GenoType® MTBDRsl v.1.0 (MTBDRsl) assay capacity to detect resistance to ofloxacin, amikacin, capreomycin, kanamycin and ethambutol in Mycobacterium tuberculosis with phenotypic drug susceptibility testing (DST) using MGIT™960™ in sputum samples and isolates.DESIGN: Fifty-three smear-positive sputum samples were tested directly by MTBDRsl and 205 MDR-TB isolates were processed using MTBDRsl and DST for five drugs on MGIT960. DNA sequencing was performed in isolates with discordance in the results between the two methods for the gyrA, gyrB and rrs genes.RESULT: Sensitivity and specificity of MTBDRsl was found to be respectively 93.1% and 100% for fluoroquinoline, respectively 75-78% and 100% for aminoglycosides/cyclopeptides, respectively 70% and 92% for ethambutol and respectively 92.3% and 100% for extensively drug-resistant (XDR) TB detection. On sequencing eight discordant isolates for quinolones, mutations were seen in 12.5% of the gyrB gene and among 20 discordant isolates for aminoglycosides/cyclopeptides in the rrs gene in 15% isolates. The turnaround time was 2 days for MTBDRsl vs. 10 days for MGIT960.CONCLUSIONS: MTBDRsl can be used as an initial rapid test for detecting XDR-TB, resistance to quinolones and aminogycosides/cyclopeptides in smear-positive sputum samples.


Assuntos
Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose Resistente a Múltiplos Medicamentos/diagnóstico , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , DNA Bacteriano/genética , Farmacorresistência Bacteriana Múltipla , Genótipo , Humanos , Mycobacterium tuberculosis/genética , Sensibilidade e Especificidade , Escarro/microbiologia , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia
9.
Sci Rep ; 8(1): 7043, 2018 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-29728633

RESUMO

Tyrosine kinase 2 (TYK2) belongs to the Janus kinase (JAK) family of tyrosine kinases, which transmit signals from activated cytokine receptors. GWAS have consistently implicated TYK2 in psoriasis susceptibility. We performed an in-depth association analysis of TYK2 using GWAS and resequencing data. Strong genetic association of three nonsynonymous variants in the exonic regions of the TYK2 gene (rs34536443, rs12720356, and rs2304256) were found. rs12720356 encoding I684S is predicted to be deleterious based on its location in the pseudokinase domain. We analyzed PBMCs from 29 individuals representing the haplotypes containing each of the significantly associated signals. STAT4 phosphorylation was evaluated by phospho-flow cytometry after CD3/CD28 activation of cells followed by IL-12 stimulation. Individuals carrying the protective I684S variant manifested significantly reduced p-STAT4 levels in CD4 + CD25 + CD45RO+ (mean Stimulation Index (S.I.) 48.08, n = 10) and CD8 + CD25 + CD45RO + cells (S.I. 55.71, n = 10), compared to controls homozygous for the ancestral haplotype (S.I. 68.19, n = 10 (p = 0.002) and 76.76 n = 10 (p = 0.0008) respectively). Reduced p-STAT4 levels were also observed in skin-homing, cutaneous lymphocyte associated antigen (CLA)-positive CD4 and CD8 cells from I684S carriers. No significant changes in p-STAT4 for the psoriasis-associated variant rs34536443 was found. These data establish the functional significance of the TYK2 I684S variant in psoriasis susceptibility.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Memória Imunológica , Interleucina-12/metabolismo , Fator de Transcrição STAT4/metabolismo , TYK2 Quinase/genética , Biomarcadores , Suscetibilidade a Doenças , Regulação da Expressão Gênica , Estudo de Associação Genômica Ampla , Humanos , Imunofenotipagem , Fosforilação , Psoríase/etiologia , Psoríase/metabolismo , Psoríase/patologia , Transdução de Sinais , Pele/imunologia , Pele/metabolismo , Pele/patologia
10.
J Fish Dis ; 41(2): 281-290, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28940578

RESUMO

Chlamydial infections are recognised as causative agent of epitheliocystis, reported from over 90 fish species. In the present study, the farmed striped catfish Pangasianodon hypophthalmus (14-15 cm, 70-90 g) with a history of cumulative mortality of about 23% during June and July 2015, were brought to the laboratory. The histopathological examination of gills from the affected fish revealed presence of granular basophilic intracellular inclusions, mostly at the base of the interlamellar region and in gill filaments. A concurrent infection with Trichodina spp., Ichthyobodo spp. and Dactylogyrus spp. was observed in the gills. The presence of chlamydial DNA in the gills of affected fish was confirmed by amplification and sequencing of 16S rRNA gene. BLAST-n analysis of these amplicons revealed maximum similarity (96%) with Candidatus Actinochlamydia clariae. On the basis of phylogenetic analysis, it was inferred that the epitheliocystis agents from striped catfish were novel and belonged to the taxon Ca. Actinochlamydia. It is proposed that epitheliocystis agents from striped catfish will be named as Ca. Actinochlamydia pangasiae. The 16S rRNA gene amplicons from novel chlamydiae were labelled and linked to inclusions by in situ hybridisation. This is the first report of epitheliocystis from India in a new fish host P. hypophthalmus.


Assuntos
Peixes-Gato , Chlamydiales/classificação , Doenças dos Peixes/patologia , Brânquias/patologia , Infecções por Bactérias Gram-Negativas/veterinária , Animais , Chlamydiales/genética , Chlamydiales/isolamento & purificação , Doenças dos Peixes/microbiologia , Brânquias/microbiologia , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Negativas/patologia , Índia , Filogenia , RNA Bacteriano/genética , RNA Ribossômico 16S/genética
11.
Arthritis Rheumatol ; 69(11): 2233-2240, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28692792

RESUMO

OBJECTIVE: Cryopyrin-associated periodic syndromes (CAPS) result from gain-of-function mutations in the NLRP3 gene, which causes excessive release of interleukin-1ß (IL-1ß) and systemic inflammation. While pathogenetic NLRP3 variant phenotypes are well-characterized, low-penetrance NLRP3 variants represent a significant clinical challenge. The aims of this study were to determine the clinical phenotype, the in vitro biologic phenotype, and the effect of anti-IL-1 treatment in patients with low-penetrance NLRP3 variants. METHODS: A multicenter study of consecutive symptomatic patients with low-penetrance NLRP3 variants recruited from 7 centers between May 2012 and May 2013 was performed. The observed findings were transferred into a study database, from which they were extracted for analysis. Controls were patients with a known pathogenetic NLRP3 variant. Clinical presentation and CAPS markers of inflammation were captured. Functional assays of inflammasome activation, including caspase 1 activity, NF-κB release, cell death, and IL-1ß release, were performed. Treatment effects of IL-1 were determined. Comparisons between low-penetrance and pathogenetic NLRP3 variants were performed. RESULTS: The study included 45 patients, 21 of which were female (47%); 26 of the patients (58%) were children. NLRP3 low-penetrance variants identified in the patients were Q703K (n = 19), R488K (n = 6), and V198M (n = 20). In the controls, 28 had pathogenetic NLRP3 variants. Patients with low-penetrance NLRP3 variants had significantly more fever (76%) and gastrointestinal symptoms (73%); eye disease, hearing loss, and renal involvement were less common. Functional inflammasome testing identified an intermediate phenotype in low-penetrance NLRP3 variants as compared to wild-type and pathogenetic NLRP3 variants. All treated patients responded to IL-1 inhibition, with complete response documented in 50% of patients. CONCLUSION: Patients with low-penetrance NLRP3 variants display a distinct clinical phenotype and an intermediate biologic phenotype, including IL-1ß and non-IL-1ß-mediated inflammatory pathway activation.


Assuntos
Síndromes Periódicas Associadas à Criopirina/genética , Febre/genética , Gastroenteropatias/genética , Inflamassomos/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Adolescente , Adulto , Idoso , Antirreumáticos/uso terapêutico , Estudos de Casos e Controles , Caspase 1/metabolismo , Morte Celular/genética , Morte Celular/imunologia , Criança , Pré-Escolar , Síndromes Periódicas Associadas à Criopirina/tratamento farmacológico , Síndromes Periódicas Associadas à Criopirina/imunologia , Síndromes Periódicas Associadas à Criopirina/metabolismo , Oftalmopatias/tratamento farmacológico , Oftalmopatias/genética , Oftalmopatias/imunologia , Oftalmopatias/metabolismo , Feminino , Febre/tratamento farmacológico , Febre/imunologia , Febre/metabolismo , Gastroenteropatias/tratamento farmacológico , Gastroenteropatias/imunologia , Gastroenteropatias/metabolismo , Variação Genética , Perda Auditiva/tratamento farmacológico , Perda Auditiva/genética , Perda Auditiva/imunologia , Perda Auditiva/metabolismo , Humanos , Lactente , Proteína Antagonista do Receptor de Interleucina 1/uso terapêutico , Interleucina-1beta/imunologia , Nefropatias/tratamento farmacológico , Nefropatias/genética , Nefropatias/imunologia , Nefropatias/metabolismo , Masculino , Pessoa de Meia-Idade , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Penetrância , Fenótipo , Resultado do Tratamento , Adulto Jovem
12.
Neuroscience ; 324: 163-76, 2016 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-26944603

RESUMO

Aluminum is a light weight and toxic metal present ubiquitously on earth, which has gained considerable attention due to its neurotoxic effects. It also has been linked ecologically and epidemiologically to several neurological disorders, including Alzheimer's disease (AD), Parkinson's disease (PD), Guamanian-Parkinsonian complex and Amyotrophic lateral sclerosis (ALS). The mechanism of aluminum neurotoxicity is poorly understood, but it is well documented that aluminum generates reactive oxygen species (ROS). Enhanced ROS production leads to disruption of cellular antioxidant defense systems and release of cytochrome c (cyt-c) from mitochondria to cytosol resulting in apoptotic cell death. Quercetin (a natural flavonoid) protects it from oxidative damage and has been shown to decrease mitochondrial damage in various animal models of oxidative stress. We hypothesized that if oxidative damage to mitochondria does play a significant role in aluminum-induced neurodegeneration, and then quercetin should ameliorate neuronal apoptosis. Administration of quercetin (10 mg/kg body wt/day) reduced aluminum (10 mg/kg body wt/day)-induced oxidative stress (decreased ROS production, increased mitochondrial superoxide dismutase (MnSOD) activity). In addition, quercetin also prevents aluminum-induced translocation of cyt-c, and up-regulates Bcl-2, down-regulates Bax, p53, caspase-3 activation and reduces DNA fragmentation. Quercetin also obstructs aluminum-induced neurodegenerative changes in aluminum-treated rats as seen by Hematoxylin and Eosin (H&E) staining. Further electron microscopic studies revealed that quercetin attenuates aluminum-induced mitochondrial swelling, loss of cristae and chromatin condensation. These results indicate that treatment with quercetin may represent a therapeutic strategy to attenuate the neuronal death against aluminum-induced neurodegeneration.


Assuntos
Alumínio/toxicidade , Hipocampo/efeitos dos fármacos , Doenças Neurodegenerativas/tratamento farmacológico , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Quercetina/farmacologia , Alumínio/sangue , Animais , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Caspase 3/metabolismo , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/patologia , Núcleo Celular/fisiologia , Cromatina/efeitos dos fármacos , Cromatina/metabolismo , Cromatina/patologia , Citocromos c/metabolismo , Fragmentação do DNA/efeitos dos fármacos , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Hipocampo/patologia , Hipocampo/fisiopatologia , Masculino , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/patologia , Mitocôndrias/fisiologia , Doenças Neurodegenerativas/patologia , Doenças Neurodegenerativas/fisiopatologia , Neurônios/patologia , Neurônios/fisiologia , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
13.
Br J Pharmacol ; 173(12): 1925-38, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26844810

RESUMO

BACKGROUND AND PURPOSE: Avoiding danger and finding food are closely related behaviours that are essential for surviving in a natural environment. Growing evidence supports an important role of gut-brain peptides in modulating energy homeostasis and emotional-affective behaviour. For instance, postprandial release of pancreatic polypeptide (PP) reduced food intake and altered stress-induced motor activity and anxiety by activating central Y4 receptors. EXPERIMENTAL APPROACH: We characterized [K(30) (PEG2)]hPP2-36 as long-acting Y4 receptor agonist and injected it peripherally into wildtype and Y4 receptor knockout (Y4KO) C57Bl/6NCrl mice to investigate the role of Y4 receptors in fear conditioning. Extinction and relapse after extinction was measured by spontaneous recovery and renewal. KEY RESULTS: The Y4KO mice showed impaired cued and context fear extinction without affecting acquisition, consolidation or recall of fear. Correspondingly, peripheral injection of [K(30) (PEG2)]hPP2-36 facilitated extinction learning upon fasting, an effect that was long-lasting and generalized. Furthermore, peripherally applied [K(30) (PEG2)]hPP2-36 before extinction inhibited the activation of orexin-expressing neurons in the lateral hypothalamus in WT, but not in Y4KO mice. CONCLUSIONS AND IMPLICATIONS: Our findings suggests suppression of excessive arousal as a possible mechanism for the extinction-promoting effect of central Y4 receptors and provide strong evidence that fear extinction requires integration of vegetative stimuli with cortical and subcortical information, a process crucially depending on Y4 receptors. Importantly, in the lateral hypothalamus two peptide systems, PP and orexin, interact to generate an emotional response adapted to the current homeostatic state. Detailed investigations of feeding-relevant genes may thus deliver multiple intervention points for treating anxiety-related disorders.


Assuntos
Sinais (Psicologia) , Extinção Psicológica/efeitos dos fármacos , Medo/efeitos dos fármacos , Polipeptídeo Pancreático/farmacologia , Receptores de Neuropeptídeo Y/metabolismo , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de Neuropeptídeo Y/deficiência
14.
Brain Struct Funct ; 221(7): 3373-91, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26365505

RESUMO

The amygdala is essential for generating emotional-affective behaviors. It consists of several nuclei with highly selective, elaborate functions. In particular, the central extended amygdala, consisting of the central amygdala (CEA) and the bed nucleus of the stria terminalis (BNST) is an essential component actively controlling efferent connections to downstream effectors like hypothalamus and brain stem. Both, CEA and BNST contain high amounts of different neuropeptides that significantly contribute to synaptic transmission. Among these, neuropeptide Y (NPY) has emerged as an important anxiolytic and fear-reducing neuromodulator. Here, we characterized the expression, connectivity and electrophysiological function of NPY and Y2 receptors within the CEA. We identified several NPY-expressing neuronal populations, including somatostatin- and calretinin-expressing neurons. Furthermore, in the main intercalated nucleus, NPY is expressed primarily in dopamine D1 receptor-expressing neurons but also in interspersed somatostatin-expressing neurons. Interestingly, NPY neurons did not co-localize with the Y2 receptor. Retrograde tract tracing experiments revealed that NPY neurons reciprocally connect the CEA and BNST. Functionally, the Y2 receptor agonist PYY3-36, reduced both, inhibitory as well as excitatory synaptic transmission in the centromedial amygdala (CEm). However, we also provide evidence that lack of NPY or Y2 receptors results in increased GABA release specifically at inhibitory synapses in the CEm. Taken together, our findings suggest that NPY expressed by distinct populations of neurons can modulate afferent and efferent projections of the CEA via presynaptic Y2 receptors located at inhibitory and excitatory synapses.


Assuntos
Tonsila do Cerebelo/citologia , Tonsila do Cerebelo/fisiologia , Potenciais Pós-Sinápticos Excitadores , Potenciais Pós-Sinápticos Inibidores , Neurônios/fisiologia , Neuropeptídeo Y/fisiologia , Receptores de Neuropeptídeo Y/fisiologia , Tonsila do Cerebelo/metabolismo , Animais , Calbindina 2/metabolismo , Núcleo Central da Amígdala/citologia , Núcleo Central da Amígdala/metabolismo , Núcleo Central da Amígdala/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/metabolismo , Neuropeptídeo Y/metabolismo , Receptores de Dopamina D1/metabolismo , Receptores de Neuropeptídeo Y/metabolismo , Núcleos Septais/citologia , Núcleos Septais/metabolismo , Núcleos Septais/fisiologia , Somatostatina/metabolismo
15.
Neuropeptides ; 55: 111-26, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26444585

RESUMO

While anxiety disorders are the brain disorders with the highest prevalence and constitute a major burden for society, a considerable number of affected people are still treated insufficiently. Thus, in an attempt to identify potential new anxiolytic drug targets, neuropeptides have gained considerable attention in recent years. Compared to classical neurotransmitters they often have a regionally restricted distribution and may bind to several distinct receptor subtypes. Neuropeptide Y (NPY) is a highly conserved neuropeptide that is specifically concentrated in limbic brain areas and signals via at least 5 different G-protein-coupled receptors. It is involved in a variety of physiological processes including the modulation of emotional-affective behaviors. An anxiolytic and stress-reducing property of NPY is supported by many preclinical studies. Whether NPY may also interact with processing of learned fear and fear extinction is comparatively unknown. However, this has considerable relevance since pathological, inappropriate and generalized fear expression and impaired fear extinction are hallmarks of human post-traumatic stress disorder and a major reason for its treatment-resistance. Recent evidence from different laboratories emphasizes a fear-reducing role of NPY, predominantly mediated by exogenous NPY acting on Y1 receptors. Since a reduction of fear expression was also observed in Y1 receptor knockout mice, other Y receptors may be equally important. By acting on Y2 receptors, NPY promotes fear extinction and generates a long-term suppression of fear, two important preconditions that could support cognitive behavioral therapies in human patients. A similar effect has been demonstrated for the closely related pancreatic polypeptide (PP) when acting on Y4 receptors. Preliminary evidence suggests that NPY modulates fear in particular by activation of Y1 and Y2 receptors in the basolateral and central amygdala, respectively. In the basolateral amygdala, NPY signaling activates inhibitory G protein-coupled inwardly-rectifying potassium channels or suppresses hyperpolarization-induced I(h) currents in a Y1 receptor-dependent fashion, favoring a general suppression of neuronal activity. A more complex situation has been described for the central extended amygdala, where NPY reduces the frequency of inhibitory and excitatory postsynaptic currents. In particular the inhibition of long-range central amygdala output neurons may result in a Y2 receptor-dependent suppression of fear. The role of NPY in processes of learned fear and fear extinction is, however, only beginning to emerge, and multiple questions regarding the relevance of endogenous NPY and different receptor subtypes remain elusive. Y2 receptors may be of particular interest for future studies, since they are the most prominent Y receptor subtype in the human brain and thus among the most promising therapeutic drug targets when translating preclinical evidence to potential new therapies for human anxiety disorders.


Assuntos
Encéfalo/metabolismo , Condicionamento Psicológico/fisiologia , Medo/fisiologia , Neurônios/metabolismo , Neuropeptídeo Y/metabolismo , Animais , Humanos , Neuropeptídeos/metabolismo
16.
Neuropharmacology ; 99: 665-74, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26314208

RESUMO

The amygdala is fundamental for associative fear and extinction learning. Recently, also the central nucleus of the amygdala (CEA) has emerged as a site of plasticity actively controlling efferent connections to downstream effector brain areas. Although synaptic transmission is primarily mediated by glutamate and GABA, neuropeptides critically influence the overall response. While neuropeptide Y (NPY) acting via postsynaptic Y1 receptors exerts an important anxiolytic and fear-reducing action, the role of the predominantly presynaptic Y2 receptors is less defined. To investigate the role of Y2 receptors in the CEA we employed viral-vector mediated over-expression of the Y2 selective agonist NPY3-36 in fear conditioning and extinction experiments. NPY3-36 over-expression in the CEA resulted in reduced fear expression during fear acquisition and recall. Interestingly, this effect was blocked by intraperitoneal injection of a brain-penetrant Y2 receptor antagonist. Furthermore, over-expression of NPY3-36 in the CEA also reduced fear expression during fear extinction of CS-induced but not context-related fear. Again, fear extinction appeared delayed by peripheral injection of a Y2 receptor antagonist JNJ-31020028. Importantly, mice with over-expression of NPY3-36 in the CEA also displayed reduced spontaneous recovery and reinstatement, suggesting that Y2 receptor activation supports a permanent suppression of fear. Local deletion of Y2 receptors in the CEA, on the other hand, increased the expression of CS-induced freezing during fear recall and fear extinction. Thus, NPY inhibits fear learning and promotes cued extinction by reducing fear expression also via activation of presynaptic Y2 receptors on CEA neurons.


Assuntos
Núcleo Central da Amígdala/metabolismo , Medo/fisiologia , Receptores de Neuropeptídeo Y/metabolismo , Animais , Benzamidas/administração & dosagem , Núcleo Central da Amígdala/efeitos dos fármacos , Fármacos do Sistema Nervoso Central/administração & dosagem , Sinais (Psicologia) , Dependovirus/genética , Extinção Psicológica/efeitos dos fármacos , Extinção Psicológica/fisiologia , Medo/efeitos dos fármacos , Vetores Genéticos , Masculino , Rememoração Mental/efeitos dos fármacos , Rememoração Mental/fisiologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neuropeptídeo Y/administração & dosagem , Neuropeptídeo Y/genética , Neuropeptídeo Y/metabolismo , Testes Neuropsicológicos , Fragmentos de Peptídeos/administração & dosagem , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Piperazinas/administração & dosagem , Receptores de Neuropeptídeo Y/agonistas , Receptores de Neuropeptídeo Y/antagonistas & inibidores , Receptores de Neuropeptídeo Y/genética
18.
In Vitro Cell Dev Biol Anim ; 51(8): 787-96, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25877070

RESUMO

The establishment and characterization of a continuous cell line from the thymus of air-breathing fish Channa striatus are described. The cell line, designated C. striatus thymus (CST), has been subcultured over 71 times and shows optimal growth at 28°C in Leibovitz's-15 (L-15) medium supplemented with 20% fetal bovine serum. The CST cells exhibited low plating efficiency which improved with increase in seeding density. The karyotype analysis revealed that CST cells have a normal diploid karyotype with 2n = 40. Partial amplification and sequencing of two mitochondrial genes, viz. 16S ribosomal RNA (rRNA) and cytochrome oxidase I, confirmed that the cell line originated from C. striatus. CST cells were successfully transfected indicating their potential application for expression of recombinant proteins. In immunocytochemical staining, CST cells showed characteristics of epithelial cells. These cells were sensitive to extracellular products of Vibrio cholerae MTCC 3904 as well as to heavy metal mercuric chloride. The CST cell line would be a useful tool in functional genomic studies such as RNA interference and gene knockout as well as for cytotoxicity studies.


Assuntos
Linhagem Celular/citologia , Perciformes/fisiologia , Timo/citologia , Animais , Linhagem Celular/fisiologia , Meios de Cultura , Cariotipagem , Perciformes/anatomia & histologia , Timo/fisiologia
19.
Dentomaxillofac Radiol ; 44(5): 20140023, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25556563

RESUMO

Soft-tissue calcification is always pathological. Metastatic calcification is calcification of soft tissues owing to hyperphosphataemia with or without hypercalcaemia. Metastatic calcification of oral cavity is extremely rare. A case report of metastatic calcification of the floor of the mouth with atypical radiologic and clinical picture is presented here along with a review of earlier reports. A chance finding of the granular oral mucosa on palpation led to a radiographic examination revealing granular calcifications of the floor of the mouth. Blood chemistry and hormone analysis revealed chronic renal failure and hyperparathyroidism. A diagnosis of metastatic calcification secondary to renal failure was made and the treatment was aimed at correcting the renal failure without any intervention for the asymptomatic calcifications. Key differences between the present case and other cases reported in the literature are outlined.


Assuntos
Calcinose/etiologia , Calcinose/patologia , Falência Renal Crônica/complicações , Soalho Bucal/patologia , Idoso , Calcinose/diagnóstico por imagem , Diagnóstico Diferencial , Feminino , Humanos , Soalho Bucal/diagnóstico por imagem , Radiografia Panorâmica
20.
Br J Dermatol ; 171(6): 1517-20, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24909542

RESUMO

BACKGROUND: NACHT, LRR and PYD domain-containing protein (NLRP)1 is part of the inflammasome multiprotein complex involved in the production of interleukin (IL)-1ß and IL-18, two cytokines strongly implicated in psoriasis pathogenesis. Genetic variations in NLRP1 are associated with a predisposition for chronic inflammatory conditions. OBJECTIVES: The aim of the study was to investigate the role of genetic variation in the NLRP1 inflammasome in psoriasis susceptibility. MATERIAL AND METHODS: Four haplotype-tagging single-nucleotide polymorphisms (SNPs) (rs6502867, rs8079034, rs878329 and rs12150220) were investigated by TaqMan allelic discrimination in a patient sample comprising 1847 individuals from 478 families and 802 healthy controls. RESULTS: Using the transmission disequilibrium test, a significant increase in the transmission of the NLRP1 rs8079034C and rs878329C alleles to patients with psoriasis was demonstrated (P = 0·006 and P = 0·033, respectively). Furthermore, homozygosity for the rs878329C allele correlated with a younger age of onset. We also observed an increase in the expression of NLRP1 mRNA in the peripheral blood cells of patients with psoriasis. This was accompanied by a higher level of circulating IL-18 and appeared to be associated with the rs878329C allele. CONCLUSIONS: Our data support the involvement of NLRP1 and the NLRP1 inflammasome in psoriasis susceptibility and further support the role of innate immunity in psoriasis.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Reguladoras de Apoptose/genética , Inflamassomos/genética , Polimorfismo de Nucleotídeo Único/genética , Psoríase/genética , Estudos de Casos e Controles , Predisposição Genética para Doença/genética , Haplótipos , Humanos , Imunidade Inata/genética , Desequilíbrio de Ligação/genética , Desequilíbrio de Ligação/imunologia , Proteínas NLR , Polimorfismo de Nucleotídeo Único/imunologia , Psoríase/imunologia , Análise de Regressão
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