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1.
Cell ; 186(22): 4803-4817.e13, 2023 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-37683634

RESUMO

Patescibacteria, also known as the candidate phyla radiation (CPR), are a diverse group of bacteria that constitute a disproportionately large fraction of microbial dark matter. Its few cultivated members, belonging mostly to Saccharibacteria, grow as epibionts on host Actinobacteria. Due to a lack of suitable tools, the genetic basis of this lifestyle and other unique features of Patescibacteira remain unexplored. Here, we show that Saccharibacteria exhibit natural competence, and we exploit this property for their genetic manipulation. Imaging of fluorescent protein-labeled Saccharibacteria provides high spatiotemporal resolution of phenomena accompanying epibiotic growth, and a transposon-insertion sequencing (Tn-seq) genome-wide screen reveals the contribution of enigmatic Saccharibacterial genes to growth on their hosts. Finally, we leverage metagenomic data to provide cutting-edge protein structure-based bioinformatic resources that support the strain Southlakia epibionticum and its corresponding host, Actinomyces israelii, as a model system for unlocking the molecular underpinnings of the epibiotic lifestyle.


Assuntos
Bactérias , Bactérias/classificação , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Metagenoma , Metagenômica , Filogenia , Actinobacteria/fisiologia
2.
BMC Med Inform Decis Mak ; 24(1): 60, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38429718

RESUMO

INTRODUCTION: Epilepsy is a disease characterized by an excessive discharge in neurons generally provoked without any external stimulus, known as convulsions. About 2 million people are diagnosed each year in the world. This process is carried out by a neurological doctor using an electroencephalogram (EEG), which is lengthy. METHOD: To optimize these processes and make them more efficient, we have resorted to innovative artificial intelligence methods essential in classifying EEG signals. For this, comparing traditional models, such as machine learning or deep learning, with cutting-edge models, in this case, using Capsule-Net architectures and Transformer Encoder, has a crucial role in finding the most accurate model and helping the doctor to have a faster diagnosis. RESULT: In this paper, a comparison was made between different models for binary and multiclass classification of the epileptic seizure detection database, achieving a binary accuracy of 99.92% with the Capsule-Net model and a multiclass accuracy with the Transformer Encoder model of 87.30%. CONCLUSION: Artificial intelligence is essential in diagnosing pathology. The comparison between models is helpful as it helps to discard those that are not efficient. State-of-the-art models overshadow conventional models, but data processing also plays an essential role in evaluating the higher accuracy of the models.


Assuntos
Inteligência Artificial , Epilepsia , Humanos , Epilepsia/diagnóstico , Convulsões/diagnóstico , Algoritmos , Aprendizado de Máquina , Eletroencefalografia
3.
J Neuroeng Rehabil ; 21(1): 48, 2024 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-38581031

RESUMO

BACKGROUND: This research focused on the development of a motor imagery (MI) based brain-machine interface (BMI) using deep learning algorithms to control a lower-limb robotic exoskeleton. The study aimed to overcome the limitations of traditional BMI approaches by leveraging the advantages of deep learning, such as automated feature extraction and transfer learning. The experimental protocol to evaluate the BMI was designed as asynchronous, allowing subjects to perform mental tasks at their own will. METHODS: A total of five healthy able-bodied subjects were enrolled in this study to participate in a series of experimental sessions. The brain signals from two of these sessions were used to develop a generic deep learning model through transfer learning. Subsequently, this model was fine-tuned during the remaining sessions and subjected to evaluation. Three distinct deep learning approaches were compared: one that did not undergo fine-tuning, another that fine-tuned all layers of the model, and a third one that fine-tuned only the last three layers. The evaluation phase involved the exclusive closed-loop control of the exoskeleton device by the participants' neural activity using the second deep learning approach for the decoding. RESULTS: The three deep learning approaches were assessed in comparison to an approach based on spatial features that was trained for each subject and experimental session, demonstrating their superior performance. Interestingly, the deep learning approach without fine-tuning achieved comparable performance to the features-based approach, indicating that a generic model trained on data from different individuals and previous sessions can yield similar efficacy. Among the three deep learning approaches compared, fine-tuning all layer weights demonstrated the highest performance. CONCLUSION: This research represents an initial stride toward future calibration-free methods. Despite the efforts to diminish calibration time by leveraging data from other subjects, complete elimination proved unattainable. The study's discoveries hold notable significance for advancing calibration-free approaches, offering the promise of minimizing the need for training trials. Furthermore, the experimental evaluation protocol employed in this study aimed to replicate real-life scenarios, granting participants a higher degree of autonomy in decision-making regarding actions such as walking or stopping gait.


Assuntos
Interfaces Cérebro-Computador , Aprendizado Profundo , Exoesqueleto Energizado , Humanos , Algoritmos , Extremidade Inferior , Eletroencefalografia/métodos
4.
Can J Physiol Pharmacol ; 101(1): 41-51, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36318824

RESUMO

Pamabrom is a diuretic that is effective in treating premenstrual syndrome and primary dysmenorrhea. The aim of this study was to examine the effect of metformin and modulators of the opioid receptor-nitric oxide (NO)-cyclic guanosine monophosphate (cGMP)-K+ channel pathway on the local antinociception induced by pamabrom. The rat paw 1% formalin test was used to assess the effects. Rats were treated with local administration of pamabrom (200-800 µg/paw) or indomethacin (200-800 µg/paw). The antinociception of pamabrom or indomethacin was evaluated with and without the local pretreatment of the blockers. Local administration of pamabrom and indomethacin produced dose-dependent antinociception during the second phase of the test. Local pretreatment of the paws with naloxone (50 µg/paw), l-nitro-arginine methyl ester (10-100 µg/paw), or 1H-(1,2,4)-oxadiazolo[4,2-a]quinoxalin-1-one (10-100 µg/paw) reverted the antinociception induced by local pamabrom, but not of indomethacin. Similarly, the K+ channel blockers glibenclamide, glipizide, 4-aminopyridine, tetraethylammonium, charybdotoxin, or apamin reverted the pamabrom-induced antinociception, but not of indomethacin. Metformin significantly blocked the antinociception of pamabrom and indomethacin. Our data suggest that pamabrom could activate the opioid receptor-NO-cGMP-K+ channel pathway to produce its peripheral antinociception in the formalin test. Likewise, a biguanide-dependent mechanism could be activated by pamabrom and indomethacin to generate antinociception.


Assuntos
Metformina , Naloxona , Feminino , Ratos , Animais , Naloxona/farmacologia , GMP Cíclico/metabolismo , Ratos Wistar , Óxido Nítrico/metabolismo , Diuréticos , Metformina/farmacologia , Indometacina , Receptores Opioides , Analgésicos/farmacologia , Bloqueadores dos Canais de Potássio/farmacologia
5.
Nucleic Acids Res ; 49(9): 4891-4906, 2021 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-33450011

RESUMO

Many of the gene regulatory processes of Plasmodium falciparum, the deadliest malaria parasite, remain poorly understood. To develop a comprehensive guide for exploring this organism's gene regulatory network, we generated a systems-level model of P. falciparum gene regulation using a well-validated, machine-learning approach for predicting interactions between transcription regulators and their targets. The resulting network accurately predicts expression levels of transcriptionally coherent gene regulatory programs in independent transcriptomic data sets from parasites collected by different research groups in diverse laboratory and field settings. Thus, our results indicate that our gene regulatory model has predictive power and utility as a hypothesis-generating tool for illuminating clinically relevant gene regulatory mechanisms within P. falciparum. Using the set of regulatory programs we identified, we also investigated correlates of artemisinin resistance based on gene expression coherence. We report that resistance is associated with incoherent expression across many regulatory programs, including those controlling genes associated with erythrocyte-host engagement. These results suggest that parasite populations with reduced artemisinin sensitivity are more transcriptionally heterogenous. This pattern is consistent with a model where the parasite utilizes bet-hedging strategies to diversify the population, rendering a subpopulation more able to navigate drug treatment.


Assuntos
Regulação da Expressão Gênica , Redes Reguladoras de Genes , Modelos Genéticos , Plasmodium falciparum/genética , Antimaláricos/farmacologia , Artemisininas/farmacologia , Resistência a Medicamentos/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Aprendizado de Máquina , Plasmodium falciparum/efeitos dos fármacos , Biologia de Sistemas , Transcrição Gênica
6.
Sensors (Basel) ; 23(13)2023 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-37447728

RESUMO

A new pandemic was declared at the end of 2019 because of coronavirus disease 2019 (COVID-19). One of the effects of COVID-19 infection is anosmia (i.e., a loss of smell). Unfortunately, this olfactory dysfunction is persistent in around 5% of the world's population, and there is not an effective treatment for it yet. The aim of this paper is to describe a potential non-invasive neurostimulation strategy for treating persistent anosmia in post-COVID-19 patients. In order to design the neurostimulation strategy, 25 subjects who experienced anosmia due to COVID-19 infection underwent an olfactory assessment while their electroencephalographic (EEG) signals were recorded. These signals were used to investigate the activation of brain regions during the olfactory process and identify which regions would be suitable for neurostimulation. Afterwards, 15 subjects participated in the evaluation of the neurostimulation strategy, which was based on applying transcranial direct current stimulation (tDCS) in selected brain regions related to olfactory function. The results showed that subjects with lower scores in the olfactory assessment obtained greater improvement than the other subjects. Thus, tDCS could be a promising option for people who have not fully regained their sense of smell following COVID-19 infection.


Assuntos
COVID-19 , Transtornos do Olfato , Estimulação Transcraniana por Corrente Contínua , Humanos , COVID-19/complicações , COVID-19/terapia , Anosmia/terapia , Anosmia/etiologia , SARS-CoV-2 , Transtornos do Olfato/terapia , Transtornos do Olfato/epidemiologia , Transtornos do Olfato/etiologia , Olfato/fisiologia
7.
Nurs Outlook ; 71(6): 102033, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37769501

RESUMO

BACKGROUND: The opioid epidemic is a major health challenge in the United States. PURPOSE: Members from the American Academy of Nursing joined to write a consensus paper about nurses' role in the opioid epidemic. METHODS: The panel reviewed the history of the opioid epidemic and policies to care for patients with opioid use disorder (OUD) and how registered nurses (RNs) and advanced practice nurses (APRNs) could increase care for people with OUD. DISCUSSION: Recommendations are presented to advance policies that empower RNs and APRNs to abate the opioid epidemic. CONCLUSION: Recommendations include (a) advance legislation that supports RNs and APRNs full scope of practice and expands professional role in pain management and addiction prevention; (b) evaluate effective policies that promote RN and APRN care; support federal elimination of X-waiver with state law alignment; (c) sustain the use of nurses in telemedicine; (d) support nursing research on nurse involvement in all aspects of OUD.


Assuntos
Prática Avançada de Enfermagem , Enfermeiras e Enfermeiros , Transtornos Relacionados ao Uso de Opioides , Humanos , Estados Unidos/epidemiologia , Analgésicos Opioides/efeitos adversos , Transtornos Relacionados ao Uso de Opioides/epidemiologia , Transtornos Relacionados ao Uso de Opioides/prevenção & controle , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Papel do Profissional de Enfermagem , Epidemia de Opioides/prevenção & controle
8.
Can J Physiol Pharmacol ; 100(4): 306-313, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34826228

RESUMO

The objective of the present study was to scrutinize the effect of nitric oxide (NO), cyclic GMP (cGMP), potassium channel blockers, and metformin on the citral-produced peripheral antinociception. The rat paw 1% formalin test was used to assess nociception and antinociception. Rats were treated with local peripheral administration of citral (10-100 µg/paw). The antinociception of citral (100 µg/paw) was evaluated with and without the local pretreatment of naloxone, NG-L-nitro-arginine methyl ester (L-NAME, a NO synthesis inhibitor), 1H-(1,2,4)-oxadiazolo(4,2-a)quinoxalin-1-one (ODQ, a soluble guanylyl cyclase inhibitor), metformin, opioid receptors antagonists, and K+ channel blockers. Injection of citral in the rat paw significantly decreased the nociceptive effect of formalin administration during the two phases of the test. Local pretreatment of the paws with L-NAME and ODQ did not reduced the citral-induced antinociception. Glipizide or glibenclamide (Kir6.1-2; ATP-sensitive K+ channel blockers), tetraethylammonium or 4-aminopyridine (KV; voltage-gated K+ channel blockers), charybdotoxin (KCa1.1; big conductance calcium-activated K+ channel blocker), apamin (KCa2.1-3; small conductance Ca2+-activated K+ channel antagonist), or metformin, but not the opioid antagonists, reduced the antinociception of citral. Citral produced peripheral antinociception during both phases of the formalin test. These effects were due to the activation of K+ channels and a biguanide-dependent mechanism.


Assuntos
GMP Cíclico , Metformina , Monoterpenos Acíclicos , Analgésicos/farmacologia , Analgésicos/uso terapêutico , Animais , GMP Cíclico/metabolismo , Metformina/farmacologia , Óxido Nítrico/metabolismo , Nociceptividade , Medição da Dor , Bloqueadores dos Canais de Potássio/farmacologia , Ratos , Ratos Wistar , Receptores Opioides/metabolismo
9.
Anaerobe ; 76: 102600, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35709938

RESUMO

Stickland amino acid fermentations occur primarily among species of Clostridia. An ancient form of metabolism, Stickland fermentations use amino acids as electron acceptors in the absence of stronger oxidizing agents and provide metabolic capabilities to support growth when other fermentable substrates, such as carbohydrates, are lacking. The reactions were originally described as paired fermentations of amino acid electron donors, such as the branched-chain amino acids, with recipients that include proline and glycine. We present a redox-focused view of Stickland metabolism following electron flow through metabolically diverse oxidative reactions and the defined-substrate reductase systems, including for proline and glycine, and the role of dual redox pathways for substrates such as leucine and ornithine. Genetic studies and Environment and Gene Regulatory Interaction Network (EGRIN) models for the pathogen Clostridioides difficile have improved our understanding of the regulation and metabolic recruitment of these systems, and their functions in modulating inter-species interactions within host-pathogen-commensal systems and uses in industrial and environmental applications.


Assuntos
Aminoácidos , Clostridium , Aminoácidos/metabolismo , Clostridium/metabolismo , Fermentação , Glicina/metabolismo , Prolina/metabolismo
10.
BMC Microbiol ; 21(1): 14, 2021 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-33407123

RESUMO

BACKGROUND: The type VI protein secretion system (T6SS) is important in diverse cellular processes in Gram-negative bacteria, including interactions with other bacteria and with eukaryotic hosts. In this study we analyze the evolution of the T6SS in the genus Xanthomonas and evaluate its importance of the T6SS for virulence and in vitro motility in Xanthomonas phaseoli pv. manihotis (Xpm), the causal agent of bacterial blight in cassava (Manihot esculenta). We delineate the organization of the T6SS gene clusters in Xanthomonas and then characterize proteins of this secretion system in Xpm strain CIO151. RESULTS: We describe the presence of three different clusters in the genus Xanthomonas that vary in their organization and degree of synteny between species. Using a gene knockout strategy, we also found that vgrG and hcp are required for maximal aggressiveness of Xpm on cassava plants while clpV is important for both motility and maximal aggressiveness. CONCLUSION: We characterized the T6SS in 15 different strains in Xanthomonas and our phylogenetic analyses suggest that the T6SS might have been acquired by a very ancient event of horizontal gene transfer and maintained through evolution, hinting at their importance for the adaptation of Xanthomonas to their hosts. Finally, we demonstrated that the T6SS of Xpm is functional, and significantly contributes to virulence and motility. This is the first experimental study that demonstrates the role of the T6SS in the Xpm-cassava interaction and the T6SS organization in the genus Xanthomonas.


Assuntos
Biologia Computacional/métodos , Sistemas de Secreção Tipo VI/genética , Xanthomonas/patogenicidade , Técnicas de Inativação de Genes , Transferência Genética Horizontal , Mutação , Filogenia , Análise de Sequência de DNA , Virulência , Xanthomonas/classificação , Xanthomonas/genética , Xanthomonas/fisiologia
11.
Can J Physiol Pharmacol ; 99(10): 1048-1056, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33857384

RESUMO

The aim of this study was to examine if the peripheral antinociception of α-bisabolol involves the participation of nitric oxide (NO) and cyclic guanosine monophosphate (cGMP) synthesis followed by K+ channel opening in the formalin test. Wistar rats were injected in the dorsal surface of the right hind paw with formalin (1%). Rats received a subcutaneous injection into the dorsal surface of the paw of vehicles or increasing doses of α-bisabolol (100-300 µg/paw). To determine whether the peripheral antinociception induced by α-bisabolol was mediated by either the opioid receptors or the NO-cGMP-K+ channels pathway, the effect of pretreatment (10 min before formalin injection) with the appropriate vehicles, naloxone, naltrexone, NG-nitro-l-arginine methyl ester (L-NAME), 1H-[1,2,4]-oxadiazolo[4,2-a]quinoxalin-1-one (ODQ), glibenclamide, glipizide, apamin, charybdotoxin, tetraethylammonium, or 4-aminopyridine on the antinociceptive effects induced by local peripheral α-bisabolol (300 µg/paw) were assessed. α-Bisabolol produced antinociception during both phases of the formalin test. α-Bisabolol antinociception was blocked by L-NAME, ODQ, and all the K+ channels blockers. The peripheral antinociceptive effect produced by α-bisabolol was not blocked by the opioid receptor inhibitors. α-Bisabolol was able to active the NO-cGMP-K+ channels pathway to produce its antinoceptive effect. The participation of opioid receptors in the peripheral local antinociception induced by α-bisabolol is excluded.


Assuntos
Analgésicos/farmacologia , GMP Cíclico/metabolismo , Sesquiterpenos Monocíclicos/farmacologia , Óxido Nítrico/metabolismo , Nociceptividade/efeitos dos fármacos , Canais de Potássio/metabolismo , Receptores Opioides/metabolismo , Animais , Masculino , Bloqueadores dos Canais de Potássio/farmacologia , Canais de Potássio/química , Canais de Potássio/genética , Ratos , Ratos Wistar , Receptores Opioides/química , Receptores Opioides/genética
12.
Clin Anat ; 34(5): 678-684, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33012024

RESUMO

INTRODUCTION: Morton's neuroma is an entrapment neuropathy of the third common plantar digital nerve, caused by the deep transverse metatarsal ligament (DTML). Minimally invasive or percutaneous surgery is a very common procedure, but surgical effectivity of this technique remains controversial. The goal of our study was to prove the effectiveness and safety of a new ultrasound-guided technique for DTML-release in a cadaver model. MATERIALS, METHODS, AND RESULTS: The DTML was visualized in 10 fresh frozen donated body to science-feet (eight male and two females, five left and five right) using an US device (GE Logic R7; 13 MHz linear probe, Madrid, Spain). Consecutively, minimally invasive ultrasound-guided surgery was performed. Exclusion criteria of the donated bodies to science were previous history of forefoot surgery and space occupying mass lesions. The complete release of the ligament was achieved in all specimens without damage of any important anatomical structures as proven by anatomical dissection. CONCLUSIONS: The results of this study indicate that our novel approach of an ultrasound-guided release of the DTML is safer and more effective compared to blind techniques. The DTML could reliably be visualized and securely cut through a dorsal, minimally invasive surgical incision of only 2 mm.


Assuntos
Pontos de Referência Anatômicos , Ligamentos Articulares/cirurgia , Ossos do Metatarso/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Ultrassonografia de Intervenção/métodos , Cadáver , Feminino , Humanos , Masculino
13.
Mol Syst Biol ; 15(3): e8584, 2019 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-30833303

RESUMO

The success of Mycobacterium tuberculosis (MTB) stems from its ability to remain hidden from the immune system within macrophages. Here, we report a new technology (Path-seq) to sequence miniscule amounts of MTB transcripts within up to million-fold excess host RNA Using Path-seq and regulatory network analyses, we have discovered a novel transcriptional program for in vivo mycobacterial cell wall remodeling when the pathogen infects alveolar macrophages in mice. We have discovered that MadR transcriptionally modulates two mycolic acid desaturases desA1/desA2 to initially promote cell wall remodeling upon in vitro macrophage infection and, subsequently, reduces mycolate biosynthesis upon entering dormancy. We demonstrate that disrupting MadR program is lethal to diverse mycobacteria making this evolutionarily conserved regulator a prime antitubercular target for both early and late stages of infection.


Assuntos
Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Redes Reguladoras de Genes , Interações Hospedeiro-Patógeno , Macrófagos/imunologia , Mycobacterium tuberculosis/fisiologia , Tuberculose/microbiologia , Adaptação Fisiológica , Animais , Antígenos de Bactérias/metabolismo , Proteínas de Bactérias/metabolismo , Parede Celular/metabolismo , Macrófagos/microbiologia , Camundongos , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/imunologia , Ácidos Micólicos/metabolismo , Biologia de Sistemas , Tuberculose/imunologia
14.
Can J Physiol Pharmacol ; 98(11): 753-762, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33095677

RESUMO

The aim of this study was to examine if the peripheral antinociceptive effects of the opioid agonist/antagonist nalbuphine and buprenorphine involve the sequential participation of nitric oxide (NO) and cyclic guanosine monophosphate (cGMP) synthesis followed by K+ channel opening in the formalin test. Wistar rats (180-220 g) were injected in the dorsal surface of the right hind paw with formalin (1%). Rats received a subcutaneous (s.c.) injection into the dorsal surface of the paw of vehicles or increasing doses of nalbuphine (50-200 µg/paw) or buprenorphine (1-5 µg/paw) 20 min before formalin injection into the paw. Nalbuphine antinociception was reversed by the s.c. injection into the paw of the inhibitor of NO synthesis (NG-nitro-l-arginine methyl ester (L-NAME)), by the inhibitor of guanylyl cyclase (1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ)), by the Kir6.1-2, ATP-sensitive K+ channel inhibitors (glibenclamide and glipizide), by the KCa2.1-3, small conductance Ca2+-activated K+ channel blocker (apamin), by the KCa1.1, large conductance Ca2+-activated K+ channel blocker (charybdotoxin), and by the KV, voltage-dependent K+ channel inhibitors (4-aminopyridine (4-AP) and tetraethylammonium chloride (TEA)). The antinociceptive effect produced by buprenorphine was blocked by the s.c. injection of 4-AP and TEA but not by L-NAME, ODQ, glibenclamide, glipizide, apamin, or charybdotoxin. The present results provide evidence for differences in peripheral mechanisms of action between these opioid drugs.


Assuntos
Analgésicos Opioides/farmacologia , Antagonistas de Entorpecentes/farmacologia , Nociceptividade/efeitos dos fármacos , Dor/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Animais , Buprenorfina/farmacologia , GMP Cíclico/metabolismo , Modelos Animais de Doenças , Glibureto/administração & dosagem , Humanos , Injeções Subcutâneas , Canais KATP/antagonistas & inibidores , Canais KATP/metabolismo , Masculino , NG-Nitroarginina Metil Éster/administração & dosagem , Nalbufina/farmacologia , Óxido Nítrico/metabolismo , Nociceptividade/fisiologia , Dor/induzido quimicamente , Dor/diagnóstico , Medição da Dor , Bloqueadores dos Canais de Potássio/administração & dosagem , Ratos , Receptores Opioides/metabolismo , Transdução de Sinais/fisiologia
15.
Chin J Physiol ; 63(5): 204-210, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33109786

RESUMO

Despite the wide application of carvacrol (CAR) in different biological and medical areas, there is still insufficient electrophysiological data on the mechanisms of action of CAR, particularly in the pregnant uterine function. The aim of this study was to evaluate the in vitro tocolytic effect of CAR on the contractility of isolated pregnant rat uterus in the presence of a calcium channel antagonist (nifedipine) and a cyclooxygenase inhibitor (indomethacin). The uteri were isolated from pregnant Wistar rats at 16-18 days of pregnancy and suspended in an isolated organ bath chamber containing a Ringer's physiological solution and aerated with 95% O2and 5% CO2. Samples were used in functional tests to evaluate the inhibitory effect of CAR at increasing concentrations on the rhythmic spontaneous, oxytocin-induced phasic, K+-induced tonic, and Ca2+-induced contractions. The differences in inhibitory concentration-50 and Emaxamong the compounds were determined using the one-way ANOVA followed by a post hoc Student-Newman-Keuls or Bonferroni test, in all casesP < 0.05 was considered statistically significant. Nifedipine was used as positive controls where required. CAR caused a significant concentration-dependent inhibition of the uterine contractions induced by the pharmaco- and electro-mechanic stimuli. We showed that the inhibitory effects of CAR depends on the type of muscle contraction stimuli, and that it acts stronger in spontaneous rhythmic activity and in contractions of isolated rat uterus induced by Ca2+. Nifedipine was more potent than CAR and indomethacin on the uterine contractility (P < 0.05), but none of them was more effective than nifedipine. Therefore, the tocolytic effect induced by CAR was associated with the blockade of the calcium channels in the pregnant rat uterus. This property placed CAR as a potentially safe and effective adjuvant agent in cases of preterm labor, an area of pharmacological treatment that requires urgent improvement.


Assuntos
Cimenos/farmacologia , Contração Muscular/efeitos dos fármacos , Tocolíticos , Útero/efeitos dos fármacos , Animais , Feminino , Fenóis , Gravidez , Ratos , Ratos Wistar , Tocolíticos/farmacologia
16.
Sensors (Basel) ; 19(24)2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31835546

RESUMO

The aim of this paper is to describe new methods for detecting the appearance of unexpected obstacles during normal gait from EEG signals, improving the accuracy and reducing the false positive rate obtained in previous studies. This way, an exoskeleton for rehabilitation or assistance of people with motor limitations commanded by a Brain-Machine Interface (BMI) could be stopped in case that an obstacle suddenly appears during walking. The EEG data of nine healthy subjects were collected during their normal gait while an obstacle appearance was simulated by the projection of a laser line in a random pattern. Different approaches were considered for selecting the parameters of the BMI: subsets of electrodes, time windows and classifier probabilities, which were based on a linear discriminant analysis (LDA). The pseudo-online results of the BMI for detecting the appearance of obstacles, with an average percentage of 63.9% of accuracy and 2.6 false positives per minute, showed a significant improvement over previous studies.


Assuntos
Eletroencefalografia/métodos , Marcha/fisiologia , Monitorização Fisiológica , Caminhada/fisiologia , Adulto , Algoritmos , Interfaces Cérebro-Computador , Eletrodos , Exoesqueleto Energizado , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Processamento de Sinais Assistido por Computador
17.
Drug Dev Res ; 79(5): 239-246, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30188586

RESUMO

Preclinical Research & Development The addition of polyunsaturated fatty acids to nonsteroidal anti-inflammatory drugs can increase their antinociceptive activity and produce a gastroprotective effect. The aim of the present study was to examine the effects of the interaction between docosahexaenoic acid (DHA) and diclofenac on inflammation (fixed ratios 1:1, 1:3, and 3:1), nociception (fixed ratio 1:3), and gastric injury in rats. DHA, diclofenac, or combinations of DHA and diclofenac produced anti-inflammatory and antinociceptive effects in rat. The administration of diclofenac produced significant gastric damage, but this effect was not observed with either DHA or the DHA-diclofenac combinations. Effective dose (ED30 ) values were estimated for each individual drug and analyzed isobolographically. The anti-inflammatory experimental ED30 values were 6.97 mg/kg (1:1 fixed ratio), 1.1 mg/kg (1:3 fixed ratio), and 11.34 mg/kg (3:1 fixed ratio). These values were significantly lower (p < .05) than the theoretical ED30 values: 67.94 mg/kg (1:1), 35.37 mg/kg (1:3), and 100.51 mg/kg (3:1). The antinociceptive experimental value was 1.25 mg/kg (1:3 fixed ratio). This value was lower (p < .05) than the theoretical ED30 , which was predicted to be 15.92 mg/kg. These data indicate that the DHA-diclofenac combinations interact at the systemic level, produce minor gastric damage, and potentially have therapeutic advantages for the clinical treatment of inflammatory pain.


Assuntos
Analgésicos/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Diclofenaco/farmacologia , Ácidos Docosa-Hexaenoicos/farmacologia , Nociceptividade/efeitos dos fármacos , Estômago/efeitos dos fármacos , Analgésicos/efeitos adversos , Analgésicos/uso terapêutico , Animais , Anti-Inflamatórios não Esteroides/efeitos adversos , Anti-Inflamatórios não Esteroides/uso terapêutico , Diclofenaco/efeitos adversos , Diclofenaco/uso terapêutico , Ácidos Docosa-Hexaenoicos/efeitos adversos , Ácidos Docosa-Hexaenoicos/uso terapêutico , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Quimioterapia Combinada , Feminino , Humanos , Inflamação/tratamento farmacológico , Ratos Wistar , Estômago/patologia
18.
Drug Dev Res ; 79(1): 29-37, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29243833

RESUMO

Preclinical Research & Development The combination of nonsteroidal anti-inflammatory drugs (NSAIDs) with herbal products having analgesic and anti-inflammatory effects may increase their beneficial effects and limit their side effects. In this study, the effects of an interaction between α-bisabolol and the NSAID, diclofenac on nociception (formalin test), inflammation (paw inflammation produced by carrageenan) and gastric injury in rat was assessed. Diclofenac, α-bisabolol, or diclofenac-α-bisabolol combinations produced antinociceptive and anti-inflammatory effects in rat (p < .05). The systemic administration of diclofenac, but not α-bisabolol, produced gastric damage while the diclofenac-α-bisabolol combinations produced limited gastric damage. Effective dose (ED40 ) values were determined for each individual drug and analyzed isobolographically. The theoretical ED40 values for the antinociceptive (98.89 mg/kg) and the anti-inflammatory (41.2 mg/kg) effects differed from the experimental ED40 values (antinociception: 38.7 mg/kg and anti-inflammation: 13.4 mg/kg). We concluded that the interactions between diclofenac and α-bisabolol are synergistic. These data suggest that the diclofenac-α-bisabolol combinations can interact to produce minor gastric damage, thereby offering a safer therapeutic alternative for the clinical management of inflammation and/or inflammatory pain.


Assuntos
Analgésicos/uso terapêutico , Anti-Inflamatórios não Esteroides/uso terapêutico , Diclofenaco/uso terapêutico , Edema/tratamento farmacológico , Nociceptividade/efeitos dos fármacos , Sesquiterpenos/uso terapêutico , Animais , Carragenina , Sinergismo Farmacológico , Edema/induzido quimicamente , Formaldeído , Masculino , Sesquiterpenos Monocíclicos , Ratos Wistar , Estômago/efeitos dos fármacos , Estômago/patologia
19.
Korean J Physiol Pharmacol ; 22(4): 391-398, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29962853

RESUMO

The aim of this study was to evaluate the in vitro anti-inflammatory and utero-relaxant effect of α-bisabolol on the pregnant human myometrium. Samples from the pregnant human myometrium were used in functional tests to evaluate the inhibitory effect of α-bisabolol (560, 860, 1,200 and 1,860 µM) on spontaneous myometrial contractions. The intracellular cyclic adenosine monophosphate (cAMP) levels generated in response to α-bisabolol in human myometrial homogenates were measured by ELISA. The anti-inflammatory effect of α-bisabolol was determined through the measurement of two pro-inflammatory cytokines, tumor necrosis factor-α (TNFα) and interleukin (IL)-1ß, and the anti-inflammatory cytokine IL-10, in pregnant human myometrial explants stimulated with lipopolysaccharide (LPS). Forskolin was used as a positive control to evaluate the cAMP and cytokine levels. α-Bisabolol was found to induce a significant inhibition of spontaneous myometrial contractions at the highest concentration level (p<0.05). α-Bisabolol caused a concentration-dependent decrease in myometrial cAMP levels (p<0.05) and a concentration-dependent decrease in LPS-induced TNFα and IL-1ß production, while IL-10 production did not increase significantly (p>0.05). The anti-inflammatory and utero-relaxant effects induced by α-bisabolol were not associated with an increase in cAMP levels in pregnant human myometrial samples. These properties place α-bisabolol as a potentially safe and effective adjuvant agent in cases of preterm birth, an area of pharmacological treatment that requires urgent improvement.

20.
Malar J ; 16(1): 431, 2017 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-29078770

RESUMO

BACKGROUND: Malaria remains a worldwide public health concern and, in Colombia, despite the efforts to stop malaria transmission, the incidence of cases has increased over the last few years. In this context, it is necessary to evaluate vector diversity, infection rates, and spatial distribution, to better understand disease transmission dynamics. This information may contribute to the planning and development of vector control strategies. RESULTS: A total of 778 Anopheles mosquitoes were collected in fifteen localities of Córdoba from August 2015 to October 2016. Six species were identified and overall, Anopheles albimanus was the most widespread and abundant species (83%). Other species of the Nyssorhynchus subgenus were collected, including Anopheles triannulatus (13%), Anopheles nuneztovari (1%), Anopheles argyritarsis (< 1%) and two species belonging to the Anopheles subgenus: Anopheles pseudopunctipennis (3%) and Anopheles neomaculipalpus (< 1%). Four species were found naturally infected with two Plasmodium species: Anopheles nuneztovari was detected naturally infected with Plasmodium falciparum and Anopheles pseudopunctipennis with Plasmodium vivax, whereas An. albimanus and An. triannulatus were found infected with both parasite species and confirmed by nested PCR. CONCLUSIONS: In general, the obtained results were contrasting with previous studies in terms of the most abundant and widespread collected species, and regarding infection rates, which were higher than those previously reported. A positive relationship between mosquito local abundance at the locality level and human infection at the municipality level was found. Mosquito local abundance and the number of houses with mosquitoes in each village are factors explaining malaria human cases in these villages. The obtained results suggest that other factors related to the apparent variation in malaria eco-epidemiology in northern Colombia, must be identified, to provide health authorities with better decision tools aiming to design control and prevention strategies.


Assuntos
Anopheles/parasitologia , Malária/transmissão , Mosquitos Vetores/parasitologia , Plasmodium/isolamento & purificação , Animais , Colômbia , Plasmodium/fisiologia , População Rural
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