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1.
PLoS Biol ; 22(2): e3002518, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38386616

RESUMO

Neurons in the subthalamic nucleus (STN) become hyperactive following nerve injury and promote pain-related responses in mice. Considering that the anterior cingulate cortex (ACC) is involved in pain and emotion processing and projects to the STN, we hypothesize that ACC neurons may contribute to hyperactivity in STN neurons in chronic pain. In the present study, we showed that ACC neurons enhanced activity in response to noxious stimuli and to alterations in emotional states and became hyperactive in chronic pain state established by spared nerve injury of the sciatic nerve (SNI) in mice. In naïve mice, STN neurons were activated by noxious stimuli, but not by alterations in emotional states. Pain responses in STN neurons were attenuated in both naïve and SNI mice when ACC neurons were inhibited. Furthermore, optogenetic activation of the ACC-STN pathway induced bilateral hyperalgesia and depression-like behaviors in naive mice; conversely, inhibition of this pathway is sufficient to attenuate hyperalgesia and depression-like behaviors in SNI mice and naïve mice subjected to stimulation of STN neurons. Finally, mitigation of pain-like and depression-like behaviors in SNI mice by inhibition of the ACC-STN projection was eliminated by activation of STN neurons. Our results demonstrate that hyperactivity in the ACC-STN pathway may be an important pathophysiology in comorbid chronic pain and depression. Thus, the ACC-STN pathway may be an intervention target for the treatment of the comorbid chronic pain and depression.


Assuntos
Dor Crônica , Camundongos , Masculino , Animais , Giro do Cíngulo/fisiologia , Hiperalgesia , Depressão , Neurônios/fisiologia
2.
J Neurosci ; 44(15)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38453468

RESUMO

The comorbidity of chronic pain and depression poses tremendous challenges for the treatment of either one because they exacerbate each other with unknown mechanisms. As the posterior insular cortex (PIC) integrates multiple somatosensory and emotional information and is implicated in either chronic pain or depression, we hypothesize that the PIC and its projections may contribute to the pathophysiology of comorbid chronic pain and depression. We show that PIC neurons were readily activated by mechanical, thermal, aversive, and stressful and appetitive stimulation in naive and neuropathic pain male mice subjected to spared nerve injury (SNI). Optogenetic activation of PIC neurons induced hyperalgesia and conditioned place aversion in naive mice, whereas inhibition of these neurons led to analgesia, conditioned place preference (CPP), and antidepressant effect in both naive and SNI mice. Combining neuronal tracing, optogenetics, and electrophysiological techniques, we found that the monosynaptic glutamatergic projections from the PIC to the basolateral amygdala (BLA) and the ventromedial nucleus (VM) of the thalamus mimicked PIC neurons in pain modulation in naive mice; in SNI mice, both projections were enhanced accompanied by hyperactivity of PIC, BLA, and VM neurons and inhibition of these projections led to analgesia, CPP, and antidepressant-like effect. The present study suggests that potentiation of the PIC→BLA and PIC→VM projections may be important pathophysiological bases for hyperalgesia and depression-like behavior in neuropathic pain and reversing the potentiation may be a promising therapeutic strategy for comorbid chronic pain and depression.


Assuntos
Dor Crônica , Neuralgia , Camundongos , Masculino , Animais , Hiperalgesia , Dor Crônica/complicações , Depressão , Córtex Insular , Tonsila do Cerebelo/metabolismo , Neuralgia/metabolismo , Comorbidade , Tálamo , Antidepressivos/uso terapêutico
3.
Gastrointest Endosc ; 97(6): 1031-1044, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36657608

RESUMO

BACKGROUND AND AIMS: Treatment strategies for early cancers or precancerous lesions of the upper GI tract in patients with cirrhosis and esophagogastric varices (EGVs) are complicated and risky. The aim of this study was to assess the efficacy and safety of endoscopic submucosal dissection (ESD) in the treatment of such patients and explore optimal treatment strategies. METHODS: We retrospectively enrolled 15 patients with cirrhosis and EGV who underwent ESD for early cancers or precancerous lesions of the upper GI tract from January 2012 to December 2021 at our center. Clinical features, endoscopic findings, treatment methods, adverse events, and follow-up data were analyzed. RESULTS: Of the 15 patients, 1 had a platelet count <30 × 1000/mm3. Five were untreated for EGV, 1 was treated after ESD, 6 were treated before ESD, 1 was treated before and during ESD, and 2 were treated during ESD. The R0 resection rate was 100%. Of the 16 mucosal lesions, 15 were endoscopic resection bleeding (ERB)-0 or ERB-c1, and 1 was ERB-c2. No patient experienced deterioration in liver function. The only adverse events were fever in 2 patients and postoperative bleeding in 2 patients. During a median follow-up of 27 months, 1 patient's esophageal high-grade dysplasia recurred at 19 months. No death resulted from the ESD procedure, liver function injury, or GI tumor itself. CONCLUSIONS: ESD is an effective and safe treatment for early cancers or precancerous lesions of the upper GI tract in patients with cirrhosis and EGV. The incidence of severe adverse events is very low due to the development of individualized clinical treatment strategies.


Assuntos
Ressecção Endoscópica de Mucosa , Lesões Pré-Cancerosas , Trato Gastrointestinal Superior , Varizes , Humanos , Estudos Retrospectivos , Ressecção Endoscópica de Mucosa/efeitos adversos , Ressecção Endoscópica de Mucosa/métodos , Recidiva Local de Neoplasia/etiologia , Lesões Pré-Cancerosas/cirurgia , Lesões Pré-Cancerosas/etiologia , Cirrose Hepática/complicações , Resultado do Tratamento
4.
BMC Endocr Disord ; 23(1): 106, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37165361

RESUMO

BACKGROUND: Central pontine myelinolysis (CPM) is a rare demyelinating disorder caused by the loss of myelin in the center of the basis pontis. CPM typically occurs with rapid correction of severe chronic hyponatremia and subsequent disturbances in serum osmolality. Although hyperglycaemia is recognized as a pathogenetic factor in serum osmolality fluctuations, CPM is rarely seen in the context of diabetes. CASE PRESENTATION: A 66-year-old Chinese male presented with a history of gait imbalance, mild slurred speech and dysphagia for two weeks. MRI showed the mass lesions in the brainstem, and laboratory examinations showed high blood glucose and HbA1c, as well as increased serum osmolality. The patient was diagnosed with CPM secondary to hyperosmolar hyperglyceamia and received insulin treatment as well as supportive therapy. After six weeks of followup, the patient had fully recovered to a normal state. CONCLUSION: CPM is a potentially fatal neurological condition and can occur in uncontrolled diabetes mellitus. Early diagnosis and timely treatment are crucial for improving the prognosis.


Assuntos
Hiperglicemia , Hiponatremia , Mielinólise Central da Ponte , Masculino , Humanos , Idoso , Mielinólise Central da Ponte/diagnóstico por imagem , Mielinólise Central da Ponte/etiologia , Hiperglicemia/complicações , Imageamento por Ressonância Magnética
5.
Acta Pharmacol Sin ; 44(11): 2169-2183, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37322164

RESUMO

Excessive self-grooming is an important behavioral phenotype of the stress response in rodents. Elucidating the neural circuit that regulates stress-induced self-grooming may suggest potential treatment to prevent maladaptation to stress that is implicated in emotional disorders. Stimulation of the subthalamic nucleus (STN) has been found to induce strong self-grooming. In this study we investigated the role of the STN and a related neural circuit in mouse stress-related self-grooming. Body-restraint and foot-shock stress-induced self-grooming models were established in mice. We showed that both body restraint and foot shock markedly increased the expression of c-Fos in neurons in the STN and lateral parabrachial nucleus (LPB). Consistent with this, the activity of STN neurons and LPB glutamatergic (Glu) neurons, as assessed with fiber photometry recording, was dramatically elevated during self-grooming in the stressed mice. Using whole-cell patch-clamp recordings in parasagittal brain slices, we identified a monosynaptic projection from STN neurons to LPB Glu neurons that regulates stress-induced self-grooming in mice. Enhanced self-grooming induced by optogenetic activation of the STN-LPB Glu pathway was attenuated by treatment with fluoxetine (18 mg·kg-1·d-1, p.o., for 2 weeks) or in the presence of a cage mate. Furthermore, optogenetic inhibition of the STN-LPB pathway attenuated stress-related but not natural self-grooming. Taken together, these results suggest that the STN-LPB pathway regulates the acute stress response and is a potential target for intervention in stress-related emotional disorders.


Assuntos
Núcleo Subtalâmico , Camundongos , Animais , Asseio Animal , Núcleo Subtalâmico/fisiologia , Neurônios/fisiologia
6.
Am J Primatol ; 84(3): e23360, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35166397

RESUMO

Gut microbiota influences nutrient metabolism and immunity of animal hosts. Better understanding of the composition and diversity of gut microbiota contributes to conservation and management of threatened animals both in situ and ex situ. In this study, we applied 16S rRNA gene amplicon sequencing to evaluate the composition and diversity of the fecal bacterial community of four gibbon genera (Family Hylobatidae) at four Chinese zoos. The results showed that the dominant bacterial phyla were Bacteroidetes, Firmicutes, and Proteobacteria and dominant families were Prevotellaceae (Bacteroidetes), Spirochaetaceae (Spirochaetes) and Ruminococcaceae (Firmicutes) in the gut of all gibbons. Both captive site and host genus had significant effects on the relative abundance of dominant bacteria and structure of gut bacterial community. We found that captive site and host genus did not solely impact gut bacterial diversity, but the interaction between them did. This study provides basic knowledge for gut microbiota of all four gibbon genera and contributes to management and conservation of captive gibbons.


Assuntos
Microbioma Gastrointestinal , Animais , Bactérias/genética , China , Firmicutes/genética , Microbioma Gastrointestinal/genética , Humanos , Hylobates , RNA Ribossômico 16S/genética
7.
Int J Neurosci ; : 1-12, 2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36514978

RESUMO

Purpose: To study the underlying molecular mechanisms of p53 in the mitochondrial dysfunction and the pathogenesis of Parkinson's disease (PD), and provide a potential therapeutic target for PD treatment.Methods: We review the contributions of p53 to mitochondrial changes leading to apoptosis and the subsequent degeneration of dopaminergic neurons in PD.Results: P53 is a multifunctional protein implicated in the regulation of diverse cellular processes via transcription-dependent and transcription-independent mechanisms. Mitochondria are vital subcellular organelles for that maintain cellular function, and mitochondrial defect and impairment are primary causes of dopaminergic neuron degeneration in PD. Increasing evidence has revealed that mitochondrial dysfunction-associated dopaminergic neuron degeneration is tightly regulated by p53 in PD pathogenesis. Neurodegenerative stress triggers p53 activation, which induces mitochondrial changes, including transmembrane permeability, reactive oxygen species production, Ca2+ overload, electron transport chain defects and other dynamic alterations, and these changes contribute to neurodegeneration and are linked closely with PD occurrence and development. P53 inhibition has been shown to attenuate mitochondrial dysfunction and protect dopaminergic neurons from degeneration under conditions of neurodegenerative stress.Conclusions: p53 appears to be a potential target for neuroprotective therapy of PD.

8.
Molecules ; 24(15)2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31344909

RESUMO

Photodynamic therapy (PDT) based periodontal disease treatment has received extensive attention. However, the deep tissue location of periodontal plaque makes the conventional PDT encounter a bottleneck. Herein, upconversion fluorescent nanomaterial with near-infrared light excitation was introduced into the treatment of periodontal disease, overcoming the limited tissue penetration depth of visible light in PDT. Photosensitizer Ce6 molecules were combined with upconversion nanoparticles (UCNPs) NaYF4:Yb,Er with a novel strategy. The hydrophobic UCNPs were modified with amphiphilic silane, utilizing the hydrophobic chain of the silane to bind to the hydrophobic groups of the UCNPs through a hydrophobic-hydrophobic interaction, and the Ce6 molecules were loaded in this hydrophobic layer. This achieves both the conversion of the hydrophobic to the hydrophilic surface and the loading of the oily photosensitizer molecules. Because the excitation position of the Ce6 molecule is in the red region, Mn ions were doped to enhance red light, and thus the improved PDT function. This Ce6 loaded UCNPs composites with efficient red upconversion luminescence show remarkable bacteriological therapeutic effect on Porphyromonas gingivalis, Prevotella intermedia and Fusobacterium nucleatum and the corresponding biofilms under 980 nm irradiation, indicating a high application prospect in the treatment of periodontal diseases.


Assuntos
Anti-Infecciosos/farmacologia , Biofilmes/efeitos dos fármacos , Nanocompostos , Porfirinas/farmacologia , Anti-Infecciosos/química , Clorofilídeos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Luz , Testes de Sensibilidade Microbiana , Nanocompostos/química , Nanopartículas/química , Periodontite/tratamento farmacológico , Periodontite/microbiologia , Fotoquimioterapia , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Porfirinas/química , Silanos/química
9.
Zhongguo Dang Dai Er Ke Za Zhi ; 19(4): 410-413, 2017 Apr.
Artigo em Zh | MEDLINE | ID: mdl-28407827

RESUMO

OBJECTIVE: To study the values of neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) in predicting the sensitivity to intravenous immunoglobulin (IVIG) in Kawasaki disease (KD). METHODS: A retrospective cohort study was conducted in 404 children with newly diagnosed KD. The data on routine blood tests, NLR, and PLR were collected before and after IVIG treatment. The receiver operating characteristic (ROC) curve was used to determine the cut-off values of NLR and PLR in predicting the insensitivity to IVIG. A logistic regression analysis was used to identify independent predictive factors for insensitivity to IVIG. RESULTS: Of all patients, 31 were insensitive to IVIG. Compared with the IVIG sensitivity group, the IVIG insensitivity group had a significantly higher incidence rate of coronary artery ectasia (P<0.01), a shorter course of disease when IVIG therapy was initiated (P<0.05), and significantly higher NLR, PLR, and C-reactive protein (CRP) level before and after treatment (P<0.05). The optimal cut-off values for NLR and PLR to predict IVIG insensitivity were 4.36 and 162 before IVIG treatment and 1.45 and 196 after treatment. The multivariate regression analysis showed that the course of disease before IVIG treatment, CRP before IVIG treatment, and NLR and PLR before and after IVIG treatment were independent predictive factors for IVIG insensitivity. CONCLUSIONS: NLR and PLR can be used to predict IVIG insensitivity in children with KD.


Assuntos
Plaquetas , Imunoglobulinas Intravenosas/uso terapêutico , Linfócitos , Síndrome de Linfonodos Mucocutâneos/tratamento farmacológico , Neutrófilos , Proteína C-Reativa/análise , Pré-Escolar , Feminino , Humanos , Lactente , Modelos Logísticos , Masculino , Síndrome de Linfonodos Mucocutâneos/sangue
10.
Tumour Biol ; 35(6): 5167-71, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24492942

RESUMO

It has been reported that FAT10 plays an important role in cell proliferation. Their activity is increased in malignant cells compared to benign cells. However, the clinical and functional significance of FAT10 expression has not been characterized previously in pancreatic ductal adenocarcinoma (PDAC). The purpose of this study was to assess FAT10 expression and to explore its contribution to PDAC. Real-time quantitative PCR was performed to examine FAT10 expression in 38 pairs of fresh frozen PDAC tissues and corresponding noncancerous tissues. Using immunohistochemistry, we performed a retrospective study of the FAT10 expression levels on 134 archival PDAC paraffin-embedded samples. The relationship between FAT10 mRNA expression and clinicopathological features was analyzed by appropriate statistics. Kaplan-Meier analysis and Cox proportional hazards regression models were used to investigate the correlation between FAT10 expression and prognosis of PDAC patients. The relative mRNA expression of FAT10 was significantly higher in PDAC tissues than in adjacent noncancerous tissues (P<0.001). By immunohistochemistry, the data revealed that high FAT10 expression was significantly correlated with clinical stage (P<0.001), histological differentiation (P=0.004), and lymph node metastasis (P=0.013). Consistent with these results, we found that high expression of FAT10 was significantly correlated with poor survival in PDAC patients (P<0.001). Furthermore, Cox regression analyses showed that FAT10 expression was an independent predictor of overall survival. In conclusion, this study confirmed the overexpression of FAT10 and its association with tumor progression in PDAC. It also provided the first evidence that FAT10 expression in PDAC was an independent prognostic factor of patients, which might be a potential diagnostic and therapeutic target of PDAC.


Assuntos
Carcinoma Ductal Pancreático/mortalidade , Neoplasias Pancreáticas/mortalidade , Ubiquitinas/fisiologia , Adulto , Idoso , Carcinoma Ductal Pancreático/química , Carcinoma Ductal Pancreático/patologia , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Pancreáticas/química , Neoplasias Pancreáticas/patologia , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Ubiquitinas/análise , Ubiquitinas/genética
11.
Analyst ; 139(3): 649-55, 2014 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-24336421

RESUMO

A novel fluorescent immunosensor was developed based on the use of CuS nanoparticles (CuS NPs) as labels for the highly sensitive detection of human prostate cancer biomarker prostate specific antigen (PSA). In the presence of CuS NPs, the non-fluorescent substrate o-phenylenediamine could be oxidized into the stable fluorescent product 2,3-diamiophenazine at physiological pH. Throughout the reaction, no other oxidizing agents (e.g. hydrogen peroxide) were needed. The relatively mild oxidation conditions made the immunoassay robust, reliable and facile. The proposed immunoassay exhibited high sensitivity and specificity for the detection of PSA. A linear relationship between the fluorescent signals and the concentration of PSA was obtained in the range of 0.5 pg mL(-1) to 50 ng mL(-1), with a detection limit of 0.1 pg mL(-1) (S/N = 3). The proposed fluorescent immunoassay can be used as a promising platform for the detection of a variety of other biomarkers.


Assuntos
Biomarcadores Tumorais/sangue , Técnicas Biossensoriais/métodos , Cobre/química , Imunoensaio/métodos , Nanopartículas Metálicas/química , Nanopartículas/química , Anticorpos/química , Anticorpos/imunologia , Humanos , Concentração de Íons de Hidrogênio , Masculino , Antígeno Prostático Específico/sangue , Reprodutibilidade dos Testes , Espectrometria de Fluorescência
12.
J Phys Condens Matter ; 36(34)2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38729174

RESUMO

Resonant exchange of the chiral Majorana fermions (MFs) that is coupled to two parallel Majorana zero modes (MZMs) or two parallel quantum dots (QDs) is investigated. We find that, in the two QDs coupling case, the resonant exchange for the chiral MFs is analogous to that in the MZM coupling case. We further propose a circuit based on topological superconductor, which is formed by the proximity coupling of a quantum anomalous Hall insulator and a s-wave superconductor, to observe the resonant exchange of chiral MFs pairs. The numerical calculations show that the resonant transmission of the chiral MFs can be adjusted by varying the coupling parameters at superconductor phase differenceΔφ=π. It is particularly noteworthy that, by only modulating the coupling strength between the two QDs, the resonant exchange may be switched on or off. By adding another MZM, the non-Abelian braiding like operation can be realized. Therefore, our design scheme may provide another way for non-Abelian braiding operation of MFs and the findings may have potential application value in the realization of topological quantum computers.

13.
Spectrochim Acta A Mol Biomol Spectrosc ; 323: 124929, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39116592

RESUMO

The competition among drugs for binding to plasma proteins is regarded as a pharmacokinetic drug interaction. Competition between antitumor agents and other drugs for plasma protein binding can alter the free concentration of the drug, potentially impacting its efficacy and increasing the risk of toxic side effects. Through a range of spectroscopic techniques, this study examined the interaction between limonin and human serum albumin (HSA) in the context of berberine (Ber) and curcumin (Cur) under physiological conditions to clarify the binding mechanisms of binary and ternary systems at the molecular level. As demonstrated by fluorescence quenching experiments, Static quenching was identified as the mechanism of interaction between HSA and limonin. The results of site competition experiments indicated that the binding site between limonin and HSA was site I, a result further supported by molecular docking simulations. Through the use of thermodynamic data calculations, it was determined that limonin forms a stable complex with HSA by establishing hydrogen bonds and van der Waals forces. Circular dichroism (CD) spectroscopy, three-dimensional (3D) fluorescence spectroscopy, and synchronous fluorescence spectroscopy (SFS) employed to validate the notion that limonin perturbed the microenvironment of amino acids and induced conformational changes in HSA. What's more, the presence of Ber or Cur was found to have further modified the alterations observed in the interaction between the original HSA-limonin binary system. In vitro cellular experiments showed that interaction with HSA reduced the antitumor activity of limonin. In contrast, adding Ber or Cur increased the inhibition rate of tumor cells. The coexistence of both Ber and Cur significantly diminished limonin's binding affinity to HSA. The current investigation enhances comprehension regarding the binding characteristics and interaction mechanisms involving limonin, Ber, Cur, and HSA. It explores the potential of HSA as a versatile drug carrier and furnishes theoretical underpinnings for co-administrative strategies.

14.
BMC Complement Med Ther ; 24(1): 19, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38178118

RESUMO

BACKGROUND: The overall comprehensive consideration of the factors influencing the recommendations in the traditional Chinese medicine (TCM) guidelines remains poorly studied. This study systematically evaluate the factors influencing recommendations formation in the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) clinical practice guidelines (CPGs) and TCM CPGs. METHODS: This was a methodological review in which we searched six databases and multiple related websites. The GRADE CPGs were identified as the guidelines developed by the GRADE Working Group or the two Co-Chairs. For the TCM CPGs, we randomly selected guidelines that were published by the TCM or integrative medicine academic societies from China mainland (published by the TCM or integrative medicine academic societies of China mainland). Two reviewers independently screened and extracted data. We included CPGs published in 2018-2022. We extracted information on the influencing factors of evidence to recommendation and conducted the analyses using descriptive statistics and calculated the proportion of relevant items by IBM SPSS Statistics and Microsoft Excel to compare the differences between the GRADE CPGs and the TCM CPGs. RESULTS: Forty-five GRADE CPGs (including 912 recommendations) and 88 TCM CPGs (including 2452 recommendations) were included. TCM recommendations mainly considered the four key determinants of desirable anticipated effects, undesirable anticipated effects, balance between desirable and undesirable effects, certainty of evidence, with less than 20% of other dimensions. And TCM CPGs presented more strong recommendations (for or against) and inappropriate discordant recommendations than GRADE CPGs. GRADE CPGs were more comprehensive considered about the factors affecting the recommendations, and considered more than 70% of all factors in the evidence to recommendation. CONCLUSIONS: The TCM CPGs lack a comprehensive consideration of multiple influencing determinants from evidence to recommendations. In the future, the correct application of the GRADE approaches should be emphasized.


Assuntos
Medicina Integrativa , Medicina Tradicional Chinesa , China , Bases de Dados Factuais
15.
Light Sci Appl ; 13(1): 166, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39009583

RESUMO

3-dB couplers, which are commonly used in photonic integrated circuits for on-chip information processing, precision measurement, and quantum computing, face challenges in achieving robust performance due to their limited 3-dB bandwidths and sensitivity to fabrication errors. To address this, we introduce topological physics to nanophotonics, developing a framework for topological 3-dB couplers. These couplers exhibit broad working wavelength range and robustness against fabrication dimensional errors. By leveraging valley-Hall topology and mirror symmetry, the photonic-crystal-slab couplers achieve ideal 3-dB splitting characterized by a wavelength-insensitive scattering matrix. Tolerance analysis confirms the superiority on broad bandwidth of 48 nm and robust splitting against dimensional errors of 20 nm. We further propose a topological interferometer for on-chip distance measurement, which also exhibits robustness against dimensional errors. This extension of topological principles to the fields of interferometers, may open up new possibilities for constructing robust wavelength division multiplexing, temperature-drift-insensitive sensing, and optical coherence tomography applications.

16.
Zhonghua Nei Ke Za Zhi ; 52(11): 936-9, 2013 Nov.
Artigo em Zh | MEDLINE | ID: mdl-24439187

RESUMO

OBJECTIVE: To understand the incidence, causes, clinical manifestations and treatment of ectopic varices (EV) in gastrointestinal (GI) tract. METHODS: GI endoscopic examinations were carried out in 99 783 patients from January 2004 to October 2012 in General Hospital of PLA. Sixty-four cases of ectopic varices in GI tract were discovered. The clinical manifestations of EV patients and treatment were analyzed retrospectively. The literatures of EV were reviewed. RESULTS: The prevalence of EV in GI was 0.06% (64/99 783) in all patients undergoing endoscopic examinations, including 5 in the gastric antrum, 37 in the duodenum, 2 in the colon, 17 in the rectum, 1 in terminal ileum as well as whole colorectum, and 2 in the anastomotic stomas. The causes of EV included portal hypertension with cirrhosis in 52 cases (42 of hepatitis as dominant, 5 of alcoholic, 3 of biliary). Twenty-five cases had past history of endoscopic sclerotherapy, tissue adhesive injection or band ligation.Extrahepatic portal vein obstruction was seen in 4 cases (1 with pancreatic cancer, gastric cardia after surgery, pancreatic cancer after surgery, small intestine after partial hepatectomy respectively) and 8 cases uncertain. Nine cases accepted endoscopic tissue adhesive injection (no post-operative hemorrhage occurred in 9 cases and EV disappeared in 3 cases). Endoscopic band ligation was performed only for one patient. CONCLUSIONS: EV in GI tract is a rare condition, which occurs commonly in duodenum, colon, and rectum. Portal hypertension is the most common cause. Gastrointestinal hemorrhage is the main clinical manifestation. EV should be considered in GI bleeding, with gastroesophageal varices hemorrhage excluded. Endoscopic adhesive injection is an effective way to treat EV.


Assuntos
Endoscopia , Varizes/diagnóstico , Adolescente , Adulto , Idoso , Feminino , Trato Gastrointestinal/irrigação sanguínea , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
17.
Anal Chem ; 84(15): 6775-82, 2012 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-22834410

RESUMO

A microfluidic platform to evaluate the expression of multi-glycans on a cell surface was developed using electrochemical impedance spectroscopy (EIS) and optical microscope technique. In the microfluidic channel, four indium tin oxide (ITO) electrodes were modified with three lectins and one passivation agent, respectively, to selectively recognize the corresponding carbohydrate epitopes on the cell surface. The binding of the cells on the electrode array was monitored by the electrochemical impedance to evaluate the expression of cell surface glycans. The excellent optical transparency of ITO electrode permitted the microscopic observation of the cell binding simultaneously to substantiate the impedance measurement. Compared with the individual technology, the double-check mode increased the sensitivity and accuracy of the assay. The experimental results using these two techniques indicated that the cell binding ability decreased in the order WGA > Con A > PNA, which was consistent with the expression difference of carbohydrate epitopes on K562 cell surface. The proposed strategy was further used for facile evaluating the variations of glycan expression on living cells in response to drugs. The consumption of cell sample for each sensing interface in the whole experiments is merely 5 × 10(3) cells. This platform offers great promise for cancer-associated glycol-biomarkers screening and further helps cancer diagnosis and treatment.


Assuntos
Espectroscopia Dielétrica , Técnicas Analíticas Microfluídicas/instrumentação , Microscopia , Polissacarídeos/metabolismo , Concanavalina A/metabolismo , Eletrodos , Humanos , Células K562 , Aglutinina de Amendoim/metabolismo , Compostos de Estanho/química , Aglutininas do Germe de Trigo/metabolismo
18.
Anal Chem ; 84(18): 7810-5, 2012 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-22913388

RESUMO

A novel multianalyte electrochemical immunoassay was developed for ultrasensitive detection of human cardiopathy biomarkers cardiac troponin I (cTnI) and human heart-type fatty-acid-binding protein (FABP) using metal ion functionalized titanium phosphate nanospheres (TiP-metal ion) as labels. The metal ions could be detected directly through square wave voltammetry (SWV) without metal preconcentration, and the distinct voltammetric peaks had a close relationship with each sandwich-type immunoreaction. The position and size of the peaks reflected the identity and level of the corresponding antigen. The large amount of metal ions loading on the TiP nanospheres greatly amplified the detection signals, and the good biocompatibility of graphene nanoribbons (GONRs) retained good stability for the sandwich-type immunoassay. The proposed immunoassay exhibited high sensitivity and selectivity for the detection of cTnI and FABP. The linear relationships between electrochemical signals and the concentrations of cTnI and FABP were obtained in the range of 0.05 pg/mL-50 ng/mL and 0.05 pg/mL-50 ng/mL, respectively. The detection limits of cTnI and HIgG were 1 and 3 fg/mL (S/N = 3), respectively. Moreover, the immunoassay accurately detected the concentrations of cTnI and FABP in human serum samples, which were demonstrated to have excellent correlations with the standard enzyme linked immunosorbent assay (ELISA) method. The results suggested that the electrochemical immunoassay would be promising in the point-of-care diagnostics application of clinical screening of acute myocardial infarction (AMI) biomarkers.


Assuntos
Técnicas Eletroquímicas , Imunoensaio , Nanosferas/química , Titânio/química , Anticorpos/imunologia , Biomarcadores/sangue , Eletrodos , Proteínas de Ligação a Ácido Graxo/sangue , Humanos , Íons/química , Sistemas Automatizados de Assistência Junto ao Leito , Troponina I/sangue
19.
Artigo em Inglês | MEDLINE | ID: mdl-36612427

RESUMO

The stress of a coal seam increases with an increase in the mining depth, which makes the failure mechanism of a coal mass more complex. To reveal the deformation and failure law of deep coal, a series of triaxial experiments was carried out via laboratory experiments and numerical simulation experiments to analyze the influence of the confining stress on the nonlinear failure characteristics of coal. Based on the crack-propagation model, the values for the inelastic flexibility S1 and the damage variable D were calculated. The results showed that the value of S1 decreased with an increase in the confining stress, which indicated that the increase in the confining pressure could inhibit the crack propagation and that the inhibitory effect was more obvious when the confining pressure increased in a small range of 4 to 12 MPa. The damage variable decreased with an increase in the confining pressure at the yield point; moreover, with an increase in the initial confining pressure, the damage rate gradually decreased. The coal body changed from the compression state to the expansion state when moving from the yield point to the peak point, and the compression value of the yield point and the dilation value of the peak point increased with the increase in the confining pressure. After the coal body entered the yield stage, the change in the confining pressure had a more significant effect on the damage to the coal body.


Assuntos
Carvão Mineral , Mineração , Pressão , Laboratórios
20.
Nat Commun ; 13(1): 7756, 2022 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-36522327

RESUMO

The basal ganglia including the subthalamic nucleus (STN) and substantia nigra pars reticulata (SNr) are involved in pain-related responses, but how they regulate pain processing remains unknown. Here, we identify a pathway, consisting of GABAergic neurons in the SNr (SNrGABA) and glutamatergic neurons in the STN (STNGlu) and the lateral parabrachial nucleus (LPBGlu), that modulates acute and persistent pain states in both male and female mice. The activity of STN neurons was enhanced in acute and persistent pain states. This enhancement was accompanied by hypoactivity in SNrGABA neurons and strengthening of the STN-LPB glutamatergic projection. Reversing the dysfunction in the SNrGABA-STNGlu-LPBGlu pathway attenuated activity of LPBGlu neurons and mitigated pain-like behaviors. Therefore, the SNrGABA-STNGlu-LPBGlu pathway regulates pathological pain and is a potential target for pain management.


Assuntos
Neurônios GABAérgicos , Substância Negra , Masculino , Feminino , Camundongos , Animais , Substância Negra/metabolismo , Estimulação Elétrica , Neurônios GABAérgicos/metabolismo , Ácido gama-Aminobutírico/metabolismo , Dor/metabolismo
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