RESUMO
In this work, we demonstrate for the first time the application of the phosphorothioated-terminal hairpin formation and self-priming extension (PS-THSP) reaction for miRNA assays. A self-priming amplification accelerating CRISPR sensor was well-established for sensitive and specific miRNA detection by integrating the PS-THSP reaction and CRISPR/Cas12a system. The sensor consists of three steps: (1) the formation of a complete PS-THSP template in the presence of target miRNA and ligase; (2) the exponential isothermal amplification of the PS-THSP reaction under the action of DNA polymerase; (3) the activation of the CRISPR/Cas12a fluorescence system to generate signals. We used miR-21 as a model target. The sensor can achieve sensitive detection of miR-21 without the involvement of any primers, and the special design of the CRISPR proto-spacer neighbor motif (PAM) sequence effectively avoids the interference of the background signal. In addition, the sensor can not only identify single-base mutant homologous sequences but also show stable performance in complex biological matrices. We have successfully used this sensor to accurately analyze miR-21 in different cell lines and real clinical samples, demonstrating its great potential in clinical diagnosis.
Assuntos
Técnicas Biossensoriais , MicroRNAs , Bioensaio , Linhagem Celular , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Primers do DNA , MicroRNAs/genética , Técnicas de Amplificação de Ácido NucleicoRESUMO
Long non-coding RNAs (lncRNAs) played vital roles in physiological and pathological conditions. Consistent results from cell experiments, animal experiments, and clinical studies suggested that lncRNA HULC was an oncogenic lncRNA serving as a potential diagnostic and prognostic marker of hepatocellular carcinoma. In this study, we developed a fluorescent biosensor for lncRNA HULC detection based on rolling circle amplification (RCA) induced by multi-primer probes. Multiple primer probes can not only combine with lncRNA to break its secondary structure, which was conducive to lncRNA captured by Y-shaped probes, but also trigger multiple RCA reactions to achieve signal amplification and the goal of sensitive detection of lncRNA. Compared to previous detection methods, in this scheme, we took advantage of the long sequence characteristics of lncRNA to make it a carrier that can bind multiple primers to initiate RCA. This newly designed biosensor provided a linear range from 1 pM to 100 nM with a detection limit of 0.06 pM. This method can provide a new idea for the application of isothermal amplification in detecting lncRNA. Furthermore, the application of the biosensor in liver cancer cell lines and whole blood samples from hepatocellular carcinomatosis patients also confirmed that the method had good selectivity and sensitivity to lncRNA HULC. This method offered a new way for transforming specific lncRNA into clinical application for diagnosis, prognosis, or predicting treatment response.
Assuntos
Técnicas Biossensoriais , Carcinoma Hepatocelular , Neoplasias Hepáticas , RNA Longo não Codificante , Animais , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/genética , RNA Longo não Codificante/genética , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/genética , Detecção Precoce de Câncer , Primers do DNA/metabolismo , Técnicas Biossensoriais/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , Limite de DetecçãoRESUMO
Biological and clinical studies have indicated that aberrant expression of circMTO1 served as a crucial biomarker for the diagnosis and prognosis of hepatocellular carcinoma (HCC) patients as well as a potential therapeutic target. However, the detection of circRNAs currently faces challenges such as homologous linear RNA interference and low-expression abundance of certain circRNAs. Therefore, we developed a triple amplification method based on catalytic hairpin assembly (CHA) activation by back-splice junction (BSJ), resulting in CHA products that triggered primer exchange reaction to generate DNAzyme. Subsequently, DNAzyme cleaved the fluorescent reporter chain, enabling ultrasensitive detection of hepatocellular carcinoma-associated circMTO1 through the output fluorescence signal. The catalytic hairpin opening sequence within CHA specifically targeted the BSJ sequence in circRNA, thereby avoiding false positive signals observed in circRNA assays due to the recognition of homologous linear RNA molecules. Moreover, this triple amplification method facilitated sensitive detection of circRNA and addressed the issue of low-abundance expression levels associated with circMTO1 in HCC samples. Notably, our newly designed assay for detecting circRNA exhibited a linear range from 1 fM to 100 nM with a detection limit of 0.265 fM. Furthermore, it demonstrated excellent and consistent performance even within complex systems. Our proposed method enabled the specific and sensitive detection of circMTO1 in various cancer cells and blood samples from HCC patients, providing an innovative approach for investigating the role of circRNA in tumorigenesis and development while promoting its clinical application.
Assuntos
Carcinoma Hepatocelular , DNA Catalítico , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/genética , RNA Circular , BioensaioRESUMO
Aptamer-based methods have attracted increasing interest due to flexible engineering, but their generality is limited by the heterogeneity of signal transduction mechanisms. Given the fact that nonlinear and large molecules are more likely to make the nanosurface overloaded, we investigated a novel signal transduction process to extend the application of aptasensors. In this work, an aptamer complementary element (ACE) is designed with a primer region to serve as the signal probe, which can fully hybridize with an aptamer and be separated by magnetic beads (MBs). Upon target binding, the formed aptamer/target complex is much larger than the linear aptamer/ACE-primer dimer, causing overload of MBs on account of steric hindrance. An extra aptamer/ACE-primer can escape from the surface to the supernatant, which can be amplified by a catalytic hairpin assembly (CHA) circle. The size-dependent signal transduction and the modular design endow the method with high generality and flexibility for protein analysis. The proposed aptasensor was successfully applied to the detection of tau proteins ranging from 0.5 to 1000 ng mL-1 with a limit of detection (LOD) as low as 0.254 ng mL-1. The recovery tests in both human serum and cerebra spinal fluid confirmed the high accuracy and stability. Furthermore, a successful distinction was made between AD patients and healthy controls by the method, suggesting the possible applicability for practical analysis of tau proteins.
Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Humanos , Limite de Detecção , Transdução de Sinais , Proteínas tau/metabolismoRESUMO
Programmed-death ligand 1 (PD-L1), as one of major immune checkpoints, is highly expressed on cancer cells and participates in the immune escape process of tumor cells. The level of PD-L1 in patients is closely related to the efficacy of anti-PD-L1 immunotherapy, and patients with a high level have better response to immunotherapy. Therefore, PD-L1 can be an indicator of patient classification and medication guidance. In this work, we have developed a novel strategy for detecting PD-L1-positive circulating tumor cells based on steric hindrance generated after cell capture, using the primer exchange reaction (PER) amplification method. The principle is to modify a single strand containing the PD-L1 aptamer and the PER primer on the electrode surface. When PD-L1-positive circulating tumor cells exist, the aptamer will capture them. The steric hindrance generated by the captured cells due to their large volume hinders the subsequent approach of PER materials, thus hindering the occurrence of PER signal amplification. The number of HRP bound to the electrode surface is reduced, and the current signal output is inversely proportional to the number of captured cells. This method realizes convenient and sensitive detection of PD-L1-positive tumor cells and provides a new means for clinical judgment of whether patients should adopt immunotherapy.
Assuntos
Células Neoplásicas Circulantes , Receptor de Morte Celular Programada 1 , Antígeno B7-H1/metabolismo , Humanos , Fatores Imunológicos , Imunoterapia/métodos , Microambiente TumoralRESUMO
Efficient capture and release of circulating tumor cells play an important role in cancer diagnosis, but the limited affinity of monovalent adhesion molecules in existing capture technologies leads to low capture efficiency, and the captured cells are difficult to be separated. Inspired by the phenomenon that the long tentacles of jellyfish contain multiple adhesion domains and can effectively capture moving food, we have constructed a biomimetic recognition strategy to capture and release tumor cells. In details, gold-coated magnetic nanomaterials (Au@Fe3O4 NPs) were first prepared and characterized by scanning electron microscopy, UV-vis absorption spectra, and Zeta potential. Then, the DNA primers modified on Au@Fe3O4 nanoparticles can be extended to form many radialized DNA products by rolling circle amplification. These long DNA products resemble jellyfish tentacles and contain multivalent aptamers that can be extended into three dimensions to increase the accessibility of target cells, resulting in efficient, simple, rapid, and specific cells capture. The capture efficiencies are no less than 92% in PBS buffer and 77% in blood. Subsequently, DNase I was selected to degrade biomimetic tentacles to release the captured tumor cells with high viability. This release strategy can not only improve cell viability, but also reduce a tedious release process and unnecessary costs. We believe that the proposed method can be expanded for the capture and release of various tumor cells and will inspire the development of circulating tumor cells analysis. A biomimetic recognition strategy for capture and release of circulating tumor cells has been developed. This method modified specific P1 DNA primers on Au@Fe3O4 NPs to form many radialized DNA products by rolling circle amplification. These products can efficiently capture CTCs since it contains multiple aptamers with a multivalent binding capacity. This make it a promising tool to capture and release of other tumor cells, and will inspire the development of CTC analysis.
Assuntos
Biomimética/métodos , Células Neoplásicas Circulantes/metabolismo , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Óxido Ferroso-Férrico/química , Ouro/química , Células HeLa , Humanos , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/toxicidade , Técnicas de Amplificação de Ácido NucleicoRESUMO
BACKGROUND: Postoperative pain impairs enhanced recovery in patients after various surgeries. Local use of ropivacaine has become an effective strategy for postoperative pain management. The aim of this study was to assess the effectiveness and safety of wound infiltration with ropivacaine for postoperative analgesia as a fast-track approach in patients undergoing thoracotomy surgery. MATERIALS AND METHODS: Forty adult patients with esophageal cancer scheduled for selective thoracotomy surgery were enrolled in this double-blind, randomized, controlled study. Patients were randomized (1:1) to receive ropivacaine or placebo wound infiltration before incision closure. Numerical rating score (NRS), postoperative analgesics consumption, length of hospital stay, time to anal exsufflation, defecation, ambulation, and patient satisfaction scores were recorded. Side effects including allergic reaction, nausea, vomiting, wound infection, and pneumonia were also assessed. RESULTS: NRS was significantly decreased in the ropivacaine group with less consumption of postsurgery analgesics. The ropivacaine group also showed shorter postoperative hospital stays, earlier anal exsufflation and ambulation, and higher patient satisfaction scores. However, there were no significant differences between the two groups regarding time of defecation. No allergic reactions occurred in either group. The incidences of nausea, vomiting, wound infection, and pneumonia were similar. CONCLUSIONS: The present study showed that ropivacaine wound infiltration could be a safe and effective fast-track approach for patients undergoing thoracotomy surgery.
Assuntos
Amidas/administração & dosagem , Anestésicos Locais/administração & dosagem , Dor Pós-Operatória/prevenção & controle , Toracotomia/efeitos adversos , Idoso , Anti-Inflamatórios não Esteroides/administração & dosagem , Método Duplo-Cego , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , RopivacainaRESUMO
Use of ß-adrenergic receptor (AR) blocker is associated with increased risk of fatigue and exercise intolerance. Nebivolol is a newer generation ß-blocker, which is thought to avoid this side effect via its vasodilating property. However, the effects of nebivolol on skeletal muscle perfusion during exercise have not been determined in hypertensive patients. Accordingly, we performed contrast-enhanced ultrasound perfusion imaging of the forearm muscles in 25 untreated stage I hypertensive patients at rest and during handgrip exercise at baseline or after 12 wk of treatment with nebivolol (5-20 mg/day) or metoprolol succinate (100-300 mg/day), with a subsequent double crossover for 12 wk. Metoprolol and nebivolol each induced a reduction in the resting blood pressure and heart rate (130.9 ± 2.6/81.7 ± 1.8 vs. 131.6 ± 2.7/80.8 ± 1.5 mmHg and 63 ± 2 vs. 64 ± 2 beats/min) compared with baseline (142.1 ± 2.0/88.7 ± 1.4 mmHg and 75 ± 2 beats/min, respectively, both P < 0.01). Metoprolol significantly attenuated the increase in microvascular blood volume (MBV) during handgrip at 12 and 20 repetitions/min by 50% compared with baseline (mixed-model P < 0.05), which was not observed with nebivolol. Neither metoprolol nor nebivolol affected microvascular flow velocity (MFV). Similarly, metoprolol and nebivolol had no effect on the increase in the conduit brachial artery flow as determined by duplex Doppler ultrasound. Thus our study demonstrated a first direct evidence for metoprolol-induced impairment in the recruitment of microvascular units during exercise in hypertensive humans, which was avoided by nebivolol. This selective reduction in MBV without alteration in MFV by metoprolol suggested impaired vasodilation at the precapillary arteriolar level.
Assuntos
Antagonistas de Receptores Adrenérgicos beta 1/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Hipertensão/tratamento farmacológico , Metoprolol/uso terapêutico , Microcirculação/efeitos dos fármacos , Microvasos/efeitos dos fármacos , Músculo Esquelético/irrigação sanguínea , Nebivolol/uso terapêutico , Vasodilatadores/uso terapêutico , Antagonistas de Receptores Adrenérgicos beta 1/efeitos adversos , Anti-Hipertensivos/efeitos adversos , Estudos Cross-Over , Células Endoteliais/enzimologia , Feminino , Antebraço , Força da Mão , Humanos , Hipertensão/diagnóstico , Hipertensão/enzimologia , Hipertensão/fisiopatologia , Masculino , Metoprolol/efeitos adversos , Microvasos/enzimologia , Microvasos/fisiopatologia , Pessoa de Meia-Idade , Contração Muscular , Fadiga Muscular , NADPH Oxidases/metabolismo , Nebivolol/efeitos adversos , Imagem de Perfusão/métodos , Fluxo Sanguíneo Regional , Texas , Resultado do Tratamento , Ultrassonografia , Vasodilatadores/efeitos adversosRESUMO
BACKGROUND: Epinephrine was recently shown to induce a hypotension episode. Activation of ß2-adrenoceptors with smooth muscle relaxation may be the underlying mechanism. This study investigated the effects of ICI 118551, a ß2-adrenoceptors antagonist, on epinephrine-induced blood pressure reduction via different administration routes in rats. METHODS: A total of 144 Sprague Dawley rats were equally randomized into 3 groups (intranasal, intravenous, and intra-arterial administration), each with 4 subgroups: saline + saline, ICI 118551 + saline, saline + epinephrine, and ICI 118551 + epinephrine. All rats were anesthetized while spontaneously breathing. Epinephrine was administered at doses of 5 µg/kg via nose, 0.25 µg/kg via femoral vein, and 0.1 µg/kg via aorta. Mean arterial pressure and heart rate were monitored. RESULTS: Mean arterial pressure decreased in all 3 saline + epinephrine subgroups after administration (P < 0.05), whereas it did not in other subgroups. Heart rate had no significant change in all subgroups. CONCLUSIONS: Epinephrine-induced blood pressure reduction can be prevented by ICI 118551 in rats, suggesting that the activation of ß2-adrenoceptors contributes to blood pressure reduction.
Assuntos
Agonistas de Receptores Adrenérgicos beta 2/administração & dosagem , Anti-Hipertensivos/administração & dosagem , Pressão Sanguínea/efeitos dos fármacos , Epinefrina/administração & dosagem , Administração Intranasal , Agonistas de Receptores Adrenérgicos beta 2/efeitos adversos , Agonistas de Receptores Adrenérgicos beta 2/química , Antagonistas de Receptores Adrenérgicos beta 2/uso terapêutico , Animais , Anti-Hipertensivos/efeitos adversos , Anti-Hipertensivos/antagonistas & inibidores , Aorta Torácica , Epinefrina/efeitos adversos , Epinefrina/antagonistas & inibidores , Veia Femoral , Frequência Cardíaca/efeitos dos fármacos , Hipotensão/induzido quimicamente , Hipotensão/prevenção & controle , Infusões Intra-Arteriais , Infusões Intravenosas , Masculino , Propanolaminas/uso terapêutico , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Receptores Adrenérgicos beta 2/química , Receptores Adrenérgicos beta 2/metabolismoRESUMO
Exosomal surface proteins are potentially useful for breast cancer diagnosis and awareness of risk. However, some detection techniques involving complex operations and expensive instrumentation are limited to advance to clinical applications. To solve this problem, we develop a dual-modal sensor combining naked-eye detection and electrochemical assay of exosomal surface proteins from breast cancer. Most of existing sensors rely on aptamers recognizing exosomes and generating amplified signals at the same time, which require well-designed aptamer probes to avoid difficulties in identifying exosomes. In our work, aptamers not bound by the exosomes can serve as complete templates to induce formation of G quadruplexes. The peroxidase activity of the G-quadruplex/hemin DNAzyme catalyze substrates can generate both color and electrochemical signals. The developed dual-modal sensor offers a remarkable capability to differentiate nonmetastatic, metastatic breast cancer patients, and healthy individuals through the analysis of exosomal surface proteins. The sensor's distinctive features, including its universality, simplicity, and cost-effectiveness, position it as a promising diagnostic tool in breast cancer research and clinical practice.
Assuntos
Técnicas Biossensoriais , Neoplasias da Mama , Colorimetria , Técnicas Eletroquímicas , Humanos , Linhagem Celular , Neoplasias da Mama/diagnóstico por imagem , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Colorimetria/instrumentação , Colorimetria/métodos , DNA Catalítico/química , DNA Catalítico/metabolismo , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Exossomos/química , Exossomos/metabolismo , Quadruplex GRESUMO
Topographic positions can mediate subsurface water availability, but its effects on tree transpiration are controversial. In humid karst regions, climax forests are usually not limited by moisture supply, even at the summit, through absorbing water from deep layers. However, little is known on the transpiration pattern and its limiting factor on the shrubland widely distributed along the karst hillslopes. In the current study, Rhus chinensis, a widely spread constructive species in natural restoration was selected. Meteorological factors, 0-300 cm soil-epikarst moisture, sap flow, and root water uptake were studied during an entire growing season to assess how hillslope positions affected transpiration. We found the mean water content in uphill was only around 60 % of that in downhill, indicating a contrasting water supply along the slope. However, there were no significant differences in the xylem isotopic composition and lc-excess which suggested the similar water uptake strategies in both uphill and downhill. R. chinensis primarily relied on the soil water rather than epikarst water (groundwater) along the hillslope because of the MixSIAR model results and more negative lc-excess values (-13.18 ). R. chinensis exhibited decreases of nearly half in the transpiration rate and amount in uphill compared to those in downhill. In downhill with sufficient water availability, transpiration followed the variation in atmospheric water demand. In uphill, a poor moisture supply limited tree transpiration and its response to atmospheric water demand. Our findings revealed that the early successional species did not entirely depend on atmospheric water demand, absorbing deep epikarst water as the mature forest. The transpiration rates of those species declined by nearly half to adapt to the water-limited environment along the hillslope in the humid karst region. This study can contribute to the evaluation of eco-hydrological functions during natural restoration.
RESUMO
Sympathetic vasoconstriction is normally attenuated in exercising muscle, but this functional sympatholysis is impaired in rats with hypertension or heart failure due to elevated levels of reactive oxygen species (ROS) in muscle. Whether ROS have a similar effect in the absence of cardiovascular disease or whether these findings extend to humans is not known. We therefore tested the hypothesis that chronic treatment with nitroglycerin (NTG) to induce nitrate tolerance, which is associated with excessive ROS production, impairs functional sympatholysis in healthy rats and humans. NTG treatment increased ethidium fluorescence in rat muscles and urinary F(2)-isoprostanes in humans, demonstrating oxidative stress. In vehicle-treated rats, sympathetic nerve stimulation (1 to 5 Hz) evoked decreases in femoral vascular conductance at rest (range, -30 to -63%) that were attenuated during hindlimb contraction (range, -2 to -31%; P < 0.05). In NTG-treated rats, vasoconstrictor responses were similar at rest, but were enhanced during contraction (range, -17 to -50%; P < 0.05 vs. vehicle). Infusion of the ROS scavenger tempol restored sympatholysis in these rats. In humans, reflex sympathetic activation during lower body negative pressure (LBNP) evoked decreases in muscle oxygenation in resting forearm (-12 ± 1%) that were attenuated during handgrip exercise (-3 ± 1%; P < 0.05). When these subjects became nitrate tolerant, LBNP-induced decreases in muscle oxygenation were unaffected at rest, but were enhanced during exercise (-9 ± 1%; P < 0.05 vs. before NTG). Collectively, these data indicate that functional sympatholysis is impaired in otherwise healthy nitrate-tolerant rats and humans by a mechanism probably involving muscle oxidative stress.
Assuntos
Contração Muscular/fisiologia , Músculo Esquelético/irrigação sanguínea , Nitratos , Estresse Oxidativo/fisiologia , Sistema Nervoso Simpático/fisiologia , Vasoconstrição/fisiologia , Adulto , Animais , Biomarcadores/urina , F2-Isoprostanos/urina , Humanos , Masculino , Modelos Animais , Contração Muscular/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Nitroglicerina/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Oxigênio/metabolismo , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Fluxo Sanguíneo Regional/efeitos dos fármacos , Fluxo Sanguíneo Regional/fisiologia , Sistema Nervoso Simpático/efeitos dos fármacos , Vasoconstrição/efeitos dos fármacos , Vasodilatadores/farmacologiaRESUMO
A simple method is proposed in this work for the detection of SARS-CoV-2 RNA based on a primer exchange reaction (PER). By ingeniously integrating the PER cascade and CRISPR/cas12a system, this method can achieve convenient detection of the target RNA in 40 min and distinguish a single-base mutation from the target sequence, demonstrating its superior analytical performance.
Assuntos
COVID-19 , SARS-CoV-2 , COVID-19/diagnóstico , Sistemas CRISPR-Cas/genética , Humanos , Técnicas de Amplificação de Ácido Nucleico/métodos , RNA Viral/genética , SARS-CoV-2/genéticaRESUMO
BACKGROUND: SGLT2i (sodium-glucose cotransporter 2 inhibitor), a class of anti-diabetic medications, is shown to reduce blood pressure (BP) in hypertensive patients with type 2 diabetes. Mechanisms underlying this action are unknown but SGLT2i-induced sympathoinhibition is thought to play a role. Whether SGLT2i reduces BP and sympathetic nerve activity (SNA) in a nondiabetic prehypertension model is unknown. METHODS: Accordingly, we assessed changes in conscious BP using radiotelemetry and alterations in mean arterial pressure and renal SNA during simulated exercise in nondiabetic spontaneously hypertensive rats during chronic administration of a diet containing dapagliflozin (0.5 mg/kg per day) versus a control diet. RESULTS: We found that dapagliflozin had no effect on fasting blood glucose, insulin, or hemoglobin A1C levels. However, dapagliflozin reduced BP in young (8-week old) spontaneously hypertensive rats as well as attenuated the age-related rise in BP in adult spontaneously hypertensive rat up to 17-weeks of age. The rises in mean arterial pressure and renal SNA during simulated exercise (exercise pressor reflex activation by hindlimb muscle contraction) were significantly reduced after 4 weeks of dapagliflozin (Δmean arterial pressure: 10±7 versus 25±14 mm Hg, Δrenal SNA: 31±17% versus 68±39%, P<0.05). Similarly, rises in mean arterial pressure and renal SNA during mechanoreflex stimulation by passive hindlimb stretching were also attenuated by dapagliflozin. Heart weight was significantly decreased in dapagliflozin compared with the control group. CONCLUSIONS: These data demonstrate a novel role for SGLT2i in reducing resting BP as well as the activity of skeletal muscle reflexes, independent of glycemic control. Our study may have important clinical implications for preventing hypertension and hypertensive heart disease in young prehypertensive individuals.
Assuntos
Diabetes Mellitus Tipo 2 , Hipertensão , Animais , Compostos Benzidrílicos , Pressão Sanguínea/fisiologia , Glucosídeos , Hipertensão/tratamento farmacológico , Contração Muscular/fisiologia , Ratos , Ratos Endogâmicos SHR , Sistema Nervoso SimpáticoRESUMO
In healthy individuals, sympathetic vasoconstriction is markedly blunted in exercising muscles to optimize blood flow to the metabolically active muscle fibres. This protective mechanism, termed functional sympatholysis, is impaired in rat models of angiotensin-dependent hypertension. However, the relevance of these findings to human hypertension is unknown. Therefore, in 13 hypertensive and 17 normotensive subjects we measured muscle oxygenation and forearm blood flow (FBF) responses to reflex increases in sympathetic nerve activity (SNA) evoked by lower body negative pressure (LBNP) at rest and during moderate-intensity rhythmic handgrip exercise. In the normotensives, LBNP caused decreases in oxygenation and FBF (−16 ± 2% and −23 ± 4%, respectively) in resting forearm but not in exercising forearm (−1 ± 2% and −1 ± 3%, respectively; P < 0.05 vs. rest). In the hypertensives, LBNP evoked decreases in oxygenation and FBF that were similar in the resting and exercising forearm (−14 ± 2% vs. −12 ± 2% and −20 ± 3% vs. −13 ± 2%, respectively; P > 0.05), indicating impaired functional sympatholysis. In the hypertensives, SNA was unexpectedly increased by 54 ± 11% during handgrip alone. However, when SNA was experimentally increased during exercise in the normotensives, sympatholysis was unaffected. Treatment for 4 weeks with the angiotensin receptor blocker irbesartan, but not with the thiazide-type diuretic chlorthalidone, restored sympatholysis in the hypertensives. These data provide the first evidence that functional sympatholysis is impaired in hypertensive humans by a mechanism that appears to involve an angiotensin-dependent increase in sympathetic vasoconstriction in the exercising muscles.
Assuntos
Pressão Sanguínea/fisiologia , Antebraço/irrigação sanguínea , Hipertensão/fisiopatologia , Consumo de Oxigênio/fisiologia , Fluxo Sanguíneo Regional/fisiologia , Sistema Nervoso Simpático/fisiopatologia , Adulto , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Compostos de Bifenilo/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Eletrocardiografia , Feminino , Força da Mão/fisiologia , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/fisiologia , Humanos , Irbesartana , Pressão Negativa da Região Corporal Inferior , Masculino , Pessoa de Meia-Idade , Contração Muscular/fisiologia , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/fisiopatologia , Consumo de Oxigênio/efeitos dos fármacos , Fluxo Sanguíneo Regional/efeitos dos fármacos , Sistema Nervoso Simpático/efeitos dos fármacos , Tetrazóis/farmacologia , Vasoconstrição/efeitos dos fármacos , Vasoconstrição/fisiologiaRESUMO
Cancer-derived exosomes have emerged as a valuable biomarker for cancer diagnosis and prognosis. However, the heterogeneity of exosomes often leads to low selectivity based on the single recognition method. Given this, we have developed a dual-aptamer recognition strategy based on G-quadruplex nanowires for selective analysis of exosomes. In this work, target exosomes were first captured by CD63 aptamers modified on magnetic beads (MBs) and then combined with AS1411 aptamer, which shows high binding affinity to nucleolin when forming stable G-quadruplex structure. Then the free myc monomer can spontaneously assemble into higher order G-wire superstructures on the allosteric AS1411, and resulting enhanced fluorescence signal, which can realize sensitive and specific analysis of the target exosomes. This dual-aptamer recognition-based method is simple and universal for different types of exosomes, which is of great significance for clinical cancer diagnosis.
Assuntos
Aptâmeros de Nucleotídeos , Exossomos , Quadruplex G , Nanofios , Neoplasias , HumanosRESUMO
The competitive endogenous RNA hypothesis is a new mechanism of RNA dialogue, in which circRNA-miRNA interaction (cmRRI) is found to be widely involved in the regulation of gene expression in tumors and other diseases. It is urgent but challenging to develop a convenient and efficient method to study the interaction between target circRNA and the candidate miRNAs. In this work, a biosensing method that allows directly analyzing cmRRI has been developed, so as to reveal the RNA dialogue strategy. The sensing system uses a bifunctional magnetic bead for the capture of target circRNA/miRNA complex as well as the signal amplification. Based on the nature of circRNA as a miRNA sponge, only if the target circRNAs and its regulatory miRNAs coexist as a complex, can the rolling circle amplification reaction be initiated to give a fluorescent signal as the output. Compared with traditional methods where the circRNA and its regulatory miRNAs have been separately analyzed, our design allows the integrated profiling of specific cmRRI by correlation characterization of two correlative RNAs, which represents a function-oriented method. The presented method also shows the analysis of the potential binding affinity of candidate miRNAs to target circRNAs. Furthermore, we have verified the ability of the sensor to directly detect cmRRI in biological samples, which reveals the promising applicability of this method for biomedical and clinical researches in the future.
Assuntos
Técnicas Biossensoriais , MicroRNAs , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , MicroRNAs/genética , RNA/genética , RNA CircularRESUMO
Numerous studies have demonstrated that sympathetic nervous system overactivation during exercise in hypertensive rodents and humans is due, in part, to an exaggerated reflex response known as the exercise pressor reflex. Our prior studies have implicated a key role of mineralocorticoid receptor activation in mediating an augmented exercise pressor reflex in spontaneously hypertensive rats, which is mitigated by blockade with eplerenone. However, the effect of eplerenone on exercise pressor reflex has not been assessed in human hypertension. Accordingly, the authors performed a randomized crossover study to compare the effects of eplerenone to another antihypertensive drug from a different class amlodipine on sympathetic nerve activity (SNA) in 14 patients with uncomplicated hypertension. The authors found that amlodipine unexpectedly augmented the increase in SNA during the second minute of isometric handgrip, which persisted into the post-exercise circulatory arrest period (∆ SNA, from rest of 15 ± 2 vs. 9 ± 2 vs. 10 ± 2 bursts/min, amlodipine vs. baseline vs. eplerenone, respectively, p < .01), suggesting an exaggerated muscle metaboreflex function. Eplerenone did not alter sympathetic responses to exercise or post-exercise circulatory arrest in the same hypertensive individuals. In conclusions, our studies provide the first direct evidence for a potentially unfavorable potentiation of muscle metaboreflex by amlodipine during isometric handgrip exercise in hypertensive patients whereas eplerenone has no significant effect. Our study may have clinical implications in terms of selection of antihypertensive agents that have the least detrimental effects on sympathetic neural responses to isometric exercise.
Assuntos
Hipertensão , Anlodipino/farmacologia , Animais , Pressão Sanguínea , Estudos Cross-Over , Eplerenona , Força da Mão , Humanos , Hipertensão/tratamento farmacológico , Músculo Esquelético , RatosRESUMO
Context: Since December 2019, more than 80,000 patients have been diagnosed with coronavirus disease 2019 (COVID-19) in China. Social support status of COVID-19 patients, especially the impact of social support on their psychological status and quality of life, needs to be addressed with increasing concern. Objectives: In this study, we used social support rating scale (SSRS) to investigate the social support in COVID-19 patients and nurses. Methods: The present study included 186 COVID-19 patients at a Wuhan mobile cabin hospital and 234 nurses at a Wuhan COVID-19 control center. Responses to a mobile phone app-based questionnaire about social support, anxiety, depression, and quality of life were recorded and evaluated. Results: COVID-19 patients scored significantly lower than nurses did on the Social Support Rating Scale (SSRS). Among these patients, 33.9% had anxiety symptoms, while 23.7% had depression symptoms. Overall SSRS, subjective social support scores and objective support scores of patients with anxiety were lower than those of patients without anxiety. This result was also found in depression. In addition, all dimensions of social support were positively correlated with quality of life. Interestingly, in all dimensions of social support, subjective support was found to be an independent predictive factor for anxiety, depression, and quality of life, whereas objective support was a predictive factor for quality of life, but not for anxiety and depression via regression analysis. Conclusion: Medical staffs should pay attention to the subjective feelings of patients and make COVID-19 patients feel respected, supported, and understood from the perspective of subjective support, which may greatly benefit patients, alleviate their anxiety and depression, and improve their quality of life.
RESUMO
BACKGROUND: It is believed that preemptive IV lornoxicam treatment can reduce the consumption of other analgesics, improve analgesic efficacy, and ameliorate immune function during patient-controlled IV analgesia. However, the effects of preemptive IV lornoxicam treatment on the analgesic efficacy of patient-controlled epidural analgesia (PCEA) with morphine and on chemokine expression remain unknown. OBJECTIVE: The aim of this prospective, randomized, controlled study was to observe the effects of preemptive IV lornoxicam treatment on the analgesic efficacy of PCEA with morphine and on the expression of monocyte chemotactic protein-1 (MCP-1) and stromal cell-derived factor-1α (SDF-1α) in women undergoing hysterectomy. METHODS: Patients undergoing elective hysterectomy with combined spinal and epidural anesthesia were randomized to 1 of 3 groups to receive IV lornoxicam 8 mg before anesthesia (group 1), lornoxicam 16-mg injection before anesthesia (group 2), or isotonic saline (control) before anesthesia. PCEA was used to treat postoperative pain, and a visual analog scale (VAS) and the Bruggemann Comfort Scale (BCS) were used to evaluate analgesic efficacy. Morphine consumption was recorded. To measure plasma concentrations of MCP-1 and SDF-1α via enzyme-linked immunosorbent assay, venous blood samples were obtained from patients at 4 separate times: before anesthesia (baseline); 0 (immediately after anesthesia administration); and 24 and 48 hours after surgery. RESULTS: Forty-five patients (mean [SD] age, 41 [5] years; mean [SD] weight, 54 [6] kg) undergoing elective hysterectomy were included in the study. There were no significant differences in VAS scores, BCS scores, or morphine consumption between the 3 groups. Compared with baseline values, MCP-1 and SDF-1α concentrations were increased significantly immediately after surgery in all 3 groups (all, P < 0.01) and returned to near-baseline values at 24 hours postsurgery in groups 1 and 2, and by 48 hours postsurgery in the control group. MCP-1 and SDF-1α concentrations in groups 1 and 2 were significantly lower than those in the control group immediately (all, P < 0.01) and 24 hours postsurgery (all, P < 0.05). CONCLUSION: Preemptive IV lornoxicam treatment was associated with attenuation of the plasma concentrations of MCP-1 and SDF-1α immediately after and 24 hours after hysterectomy and was associated with more rapid resolution to near-baseline concentrations of both cytokines in these patients compared with controls; however, it was not associated with significantly reducing epidural morphine consumption.