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1.
ACS Chem Neurosci ; 15(9): 1893-1903, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38613492

RESUMEN

Depression is a common mental disorder. In recent years, more and more attention has been paid to depression and its etiology and pathogenesis. This review aims to explore the neuroprotective and antidepressant effects of hop components. By establishing an in vitro cell damage model using PC12 cells induced by corticosterone (CORT) and an in vivo depression model through the intracranial injection of lipopolysaccharide (LPS) in mice, hop ethyl acetate extract (HEA) was used to study the protective effect and mechanism of HEA on neuronal cells in vitro and the antidepression effect and mechanism in vivo. The results showed that HEA increased the survival and decreased the rate of lactate dehydrogenase (LDH) release, apoptosis, and the ROS and NO content of CORT-induced PC12 cells. HEA alleviated depressive-like behavior, neuroinflammation, reduction of norepinephrine, and dendritic spines induced by intracerebroventricular injection of LPS in mice and increases the expression levels of BDNF, SNAP 25, and TrkB proteins without any significant side effects or toxicity. Hops demonstrated significant comprehensive utilization value, and this work provided an experimental basis for the role of hops in the treatment of depression and provided a basis for the development of HEA for antidepressant drugs or dietary therapy products.


Asunto(s)
Acetatos , Antidepresivos , Corticosterona , Depresión , Humulus , Fármacos Neuroprotectores , Extractos Vegetales , Animales , Células PC12 , Ratones , Depresión/tratamiento farmacológico , Extractos Vegetales/farmacología , Acetatos/farmacología , Antidepresivos/farmacología , Ratas , Fármacos Neuroprotectores/farmacología , Masculino , Humulus/química , Lipopolisacáridos/farmacología , Modelos Animales de Enfermedad , Conducta Animal/efectos de los fármacos
2.
ACS Appl Bio Mater ; 6(11): 5105-5113, 2023 11 20.
Artículo en Inglés | MEDLINE | ID: mdl-37903779

RESUMEN

Thrombolytic therapy for ischemic stroke still has several limitations, such as a narrow therapeutic time window and adverse effects. Therapeutic hypothermia is a neuroprotective strategy for stroke. In this study, we developed pH/temperature dual-responsive protein-polymer conjugates (PEG-uPA-PEG-PPG-PEG) by modifying a urokinase-type plasminogen activator (uPA) with polyethylene glycol (PEG) and poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) (PEG-PPG-PEG, a thermosensitive polymer) via pH-sensitive imine bonds and disulfide bonds, respectively. At 37 °C and pH 7.4 (normothermia and physiological pH), PEG-uPA-PEG-PPG-PEG exhibits antiprotease hydrolysis and masked bioactivity of uPA due to the protective effect of the polymer segments wrapped around the protein surface. However, at 33 °C and pH 6.0 (hypothermia and pH at the thrombotic site), uPA loses the protective effect and recovers its bioactivity due to PEG dissociation and PEG-PPG-PEG stretching. The masked bioactivity of uPA at normothermia and physiological pH could reduce the risk of acute hemorrhage complication, and the recovery of protein activity at acidic pH and 33 °C is of great significance for thrombolytic therapy at mild hypothermia. Thus, PEG-uPA-PEG-PPG-PEG provides promising potential for therapeutic hypothermia in ischemic stroke.


Asunto(s)
Hipotermia Inducida , Hipotermia , Accidente Cerebrovascular Isquémico , Humanos , Polímeros/uso terapéutico , Temperatura , Polietilenglicoles/uso terapéutico , Concentración de Iones de Hidrógeno
3.
Int J Pharm ; 643: 123246, 2023 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-37467814

RESUMEN

Chitosan-based injectable hydrogels were designed and fabricated through the dynamic crosslinking of dual-reversible covalent bonds (imine and phenylboronate ester) for precise insulin release. The hydrogels contain dual glucose-sensors/responsive elements, featuring high sensitivity and rapid responsiveness to glucose level variation in cumulative and half-hourly pulsed insulin release. The hydrogels demonstrated improved cytocompatibility against HSF cells and histological long-term analysis of tissue after implantation. Evaluation of the glycemic control ability in STZ-induced hyperglycemic mice revealed that the hydrogel system showed excellent glycemic control ability in the glucose tolerance test and maintained blood glucose levels in a normal range for up to 11 days after a single administration. Thus, the hydrogel system showed applicable potential in insulin replacement therapy for diabetes mellitus.


Asunto(s)
Quitosano , Diabetes Mellitus , Ratones , Animales , Insulina , Hidrogeles/química , Quitosano/química , Glucosa
4.
ACS Omega ; 7(18): 15411-15422, 2022 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-35571818

RESUMEN

Three different pore sizes of oxacalix[m]arene[n]pyrimidines modified with a naphthalene substituent were synthesized and characterized by HRMS, 1H NMR, and single-crystal analysis (8OA and 8OA-N). Steady-state spectroscopy indicates these naphthalene-oxacalix[m]arenes exhibit good fluorescence properties, which isattributed to the locally excited (LE) state emission, and electrochemical results show that the photoinduced electron transfer (PET) process occurs from the naphthalene substituent to the linked pyrimidine. Nanosecond transient absorption spectra, singlet oxygen quantum yields (ΦΔ4OA-N = 45.1%, ΦΔ6OA-N = 56.6%, and ΦΔ8OA-N = 65.7%) and theoretical calculations demonstrate that the torsion angle between the donor (naphthalene) and the acceptor (pyrimidine) promotes intersystem crossing (ISC), and the lifetime of the triplet state reaches ca. 8 ms. Interestingly, all three host molecules (4OA-N, 6OA-N, and 8OA-N) showed a high affinity for fullerene C60, and significant binding constants in the range of 4.10-6.68 × 104 M-1 were obtained by fluorescence titration; in contrast, previous reports indicated that the similar oxacalix[m]arene[n]pyrimidine scaffold could not efficiently complex with C60. In the frontier molecular orbital theory calculations of the supramolecular system of 4OA-N@C 60 , the HOMO is distributed on 4OA-N and the LUMO is localized on fullerene. The calculation results further demonstrated that there are strong interactions between the host and the fullerene guest, which is consistent with the result of the experiments. The characteristic photophysical properties of these novel naphthyl-decorated oxacalix[m]arene[n]pyrimidines broaden their application field, and the stable host-guest system with fullerene can be applied to supramolecular chemistry.

5.
ACS Omega ; 7(17): 14690-14696, 2022 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-35557655

RESUMEN

Although Amphotericin B (AmB) is considered as the "gold standard" treatment for deep fungal infections, owing to its excellent antifungal effect, it often causes severe hemolytic toxicity and nephrotoxicity, which limits its clinical use. We designed and synthesized AmB derivatives by attaching salicylic acid (SA) to the carboxyl group and confirmed their structures using 1H NMR, 13C NMR, HR-MS, and IR. We evaluated its biological activity in vitro and measured its ultraviolet-visible (UV-vis) absorption spectrum. The AmB-SA conjugates exhibited good antifungal effects against Candida albicans, Candida glabrata, and Cryptococcus neoformans compared with AmB, and the renal cytotoxicity toward HEK 293T cells in vitro was significantly reduced, with almost no nephrotoxicity in the therapeutic window of the drug. At the same time, the hemolytic toxicity was significantly reduced. Therefore, modification of AmB by introducing SA is an effective strategy to maintain the broad antifungal activity of AmB and reduce its cytotoxicity. These AmB derivatives could be applied in clinical therapy in the future.

6.
J Hazard Mater ; 423(Pt B): 127137, 2022 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-34560486

RESUMEN

Most natural polymers exhibit limited functional groups, which is not favourable for the adsorption of various ions and their utilisation. To overcome this drawback, a novel in-situ-doped nano-calcium carbonate (CaCO3) chitin hydrogel was synthesised as an efficient adsorbent for Cu (II) and Cd (II) ions. Scanning electron microscopy and Brunauer-Emmett-Teller results revealed that the synthesised CaCO3/chitin hydrogel exhibited loose macropores and mesopores. Subsequently, Fourier transform infrared, Raman, and X-ray diffraction characterisation characterisation proved that chitin was successfully doped with nano-CaCO3. The mechanical properties of CaCO3/chitin hydrogel were superior to those of the unmodified chitin hydrogel and could efficiently adsorb Cu (II) and Cd (II) ions in water. The effect of pH, initial concentration, adsorbent dosage, and temperature was assessed to determine the adsorption properties of the hydrogel. Under suitable experimental conditions, the maximum adsorption rate of the CaCO3/chitin hydrogel was approximately 96%. The time-dependent adsorption kinetics followed a quasi-second order model, and the adsorption process followed the Langmuir model. The maximum adsorption capacities of Cu (II) and Cd (II) according to the Langmuir curve were 194.61 and 191.58 mg/g, respectively. Compared with the binary competitive system, the material exhibited a specific selectivity to the adsorption of Cu (II). X-ray photoelectron spectroscopy (XPS) revealed that nitrogen and oxygen atoms were involved in chelation with the metal ions. The successful compounding of calcium carbonate nanoparticles provided more active adsorption sites for the gel. The novel material exhibited excellent adsorption effects on Cu (II) and Cd (II) ions when applied to a water sample. Thus, the novel material exhibits excellent potential for application. The Cu (II) and Cd (II)ion removal efficiencies after five successive adsorption cycles were higher than 90%, which indicated that the composite material exhibited excellent stability and reproducibility.


Asunto(s)
Cadmio , Contaminantes Químicos del Agua , Adsorción , Carbonato de Calcio , Quitina , Cobre , Hidrogeles , Concentración de Iones de Hidrógeno , Iones , Cinética , Reproducibilidad de los Resultados , Contaminantes Químicos del Agua/análisis
7.
Medicine (Baltimore) ; 98(5): e14305, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30702604

RESUMEN

It was aimed to report 5 cases of pharyngeal hairy polyps, and to summarize the characteristics combined with literature review.Five cases with pathological diagnosis of pharyngeal hair polyps were diagnosed and treated in our department from June, 2006 to October, 2016, and retrospective analysis of their clinical data was performed. Among the 5 cases, there were 1 male and 4 female, with the age of 2 days to 26 months old. After birth, these patients were accompanied by stridor, difficulty breathing, snoring, feeding difficulties, and slow weight gain.Gray mass in the stem original from the pharynx was found in all 5 cases, with the surface hair-covering. The polyp resections were performed under general anesthesia, with the complete removal of polyp along the pars basilaris during surgery smoothly. The operation during was 5 to 20 minute, with an average of 12 minute, and there was little hemorrhage during operation. Symptoms disappeared completely after the surgery, and follow-up was performed for 1 year without recurrence shown.Pharyngeal hairy polyp is a rare non-malignant clinical disease, mainly caused by symptoms in respiratory tract obstruction. Complete removal of polyps along the pars basilaris is an effective treatment, with no recurrence case reported after surgery.


Asunto(s)
Enfermedades Faríngeas/patología , Enfermedades Faríngeas/cirugía , Pólipos/patología , Pólipos/cirugía , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Imagen por Resonancia Magnética , Masculino , Enfermedades Faríngeas/diagnóstico por imagen , Pólipos/diagnóstico por imagen , Estudios Retrospectivos
8.
Medicine (Baltimore) ; 97(26): e11242, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29952988

RESUMEN

RATIONALE: Pharyngeal foreign bodies are a common complaint in emergent cases, and sometimes can be lethal. A large variety of foreign bodies may lodge in the pharynx. We present a case of uncommon foreign body in the hypopharynx. PATIENT CONCERNS: A 9-month-old boy presented for an hour of crying associated with having congee. No abnormality was revealed in physical examination or cervicothoracic computed tomography (CT) scan. Flexible laryngoscopy showed a size tag on the posterior hypopharyngeal wall. DIAGNOSES: Foreign body in the hypopharynx. INTERVENTIONS: The foreign body was removed from the hypopharynx. OUTCOMES: The patient was discharged after the removal of the foreign body. LESSONS: Infants with foreign bodies in the hypopharynx may presented with no obvious clinical manifestation. Pharyngeal foreign bodies may be the potential for disastrous consequences. Otolaryngologists should pay attention to these foreign bodies.


Asunto(s)
Cuerpos Extraños/diagnóstico , Hipofaringe/lesiones , Laringoscopía/métodos , Humanos , Lactante , Masculino
9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 37(2): 356-60, 2017 Feb.
Artículo en Chino | MEDLINE | ID: mdl-30264961

RESUMEN

Avalanche photodiode is widely used in laser rangefinder due to high gain characteristics, but introduces highly additive noise during the time of current's multiplication that makes laser rangefinder's SNR meet bottleneck. This paper proposes a method of designing a high SNR's graphene photodetector based on microcavity. The graphene's unique optoelectronic properties make it an ideal platform for a variety of photonic applications, such as fast lasers, optical modulators, transparent electrodes, and ultrafast photodetectors. It has been recognized internationally to have dominant advantages in photodetectors due to its high carrier mobility, gapless spectrum, and frequency-independent absorption coefficient. With the wavelength of 1.06 µm, the mechanism of light waves' transmission in the cavity and the graphehne's absorption are studied by using optical transmission matrix method and scattering matrix method; the light absorption model of the graphene photodetector based on microcavity is established. Device's final quantum efficiency reaches 91.2%, respectively reaches 0.778 A·W(-1), its full width at half maximum (FWHM) reaches 6 nm; the influence between graphene's position in the microcavity and device's absorption shows that device's absorption's peak value changes periodically with graphene's position under resonant condition, and the variety of length of microcavity does not have any influence on the peak value, but changes the graphene's position when absorption reaches peak value, on the condition that the length of microcavity is n times of half of wavelength, the number of device's absorption peak value is 2n with the variety of graphene's position, and all the peak values are symmetrical with respect to the center of microcavity, the final graphene's position is 0.402 8 mm away from the top mirror of microcavity, and the absorption reaches 94%, Compared with single layer graphene, the absorption rate increases 16 dB; By solving SNR equation of the graphene photodetector based on microcavity and SNR equation of the avalanche photodiode, eventually finds that the SNR of the graphene photodetector based on microcavity is 90.3, which raises 10 dB compared with the avalanche photodiode's. Theoretical analysis shows the graphene photodetector based on microcavity has high absorption rate, high quantum efficiency, and high SNR. In this paper, the research achievements provide a theoretical reference to update and design higher SNR photodetector used in laser rangefinder's receiving system.

11.
Artículo en Chino | MEDLINE | ID: mdl-20806857

RESUMEN

OBJECTIVE: To investigate the clinical pathological features of children tracheobronchial foreign bodies and to improve diagnosis and treatment. METHOD: A retrospective study 368 children cases with tracheobronchial foreign bodies in our hospital. Each patient was analyzed for age, sex, nature,complication and location of the foreign body, results of bronchoscopic removal and presence of foreign bodies in the airways. Among this cases, three of them coughed out the foreign body before operation; two of them failed to be operated for serious complication, others were conducted by rigid bronchoscopy and bronchoscopic removal with general anaesthesia. RESULT: Three children of 368 coughed out the foreign body before operation; 4 children of them were dead for the long heartbeat respiratory arrest and deep coma; 2 children of them suffered form hypoxic ischemic encephalopathy and epilepsy; others were successfully taken out by operation. CONCLUSION: For the diagnosis of children cases with tracheobronchial foreign bodies, it is very important to collect the detailed history of foreign body inhalation, physical examination and careful analysis on the findings from chest radiographs or CT scan.


Asunto(s)
Bronquios , Cuerpos Extraños/diagnóstico por imagen , Cuerpos Extraños/terapia , Tráquea , Anestesia General , Broncoscopía , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Radiografía Torácica , Estudios Retrospectivos
12.
Artículo en Chino | MEDLINE | ID: mdl-21171386

RESUMEN

AIM: To investigate whether NR2B-pERK1/2-pElk-1 signaling contributes to the Y-maze learning and memory of rat brain. METHODS: 45 adult male SD rats were divided into 4 groups: (1) Ifenprodil peritoneal injection group (Ifenprodil ip, n = 14); (2) DMSO peritoneal injection group(DMSO ip, n = 15); (3) Ifenprodil cerebral ventricle injection group (Ifenprodil ic, n = 8); (4) DMSO cerebral ventricle injection group(DMSO ic, n = 8). Y-maze training and test were used as an learning and memory enhancing stimulus. Immunohistochemical and Western blotting methods were used for detecting pERK1/2 and pElk-1 expression intensity of different brain regions. RESULTS: Compared with the DMSO ip group, the ifenprodil ip group showed no change on the Y-maze learning score (P > 0.05), but its Y-maze memory score tested 24 after learning decreased (P < 0.05). Ifenprodil peritoneal injection made brain pERK1/2 and pElk-1 expression decreased generally. In hippocampus, marginal division of striatum(MrD), amygdala,these changes were more significant (P < 0.05). Compared with the DMSO ic group, the reconsolidation of Y-maze memory tested 6 hours after ifenprodil injection was impaired in ifenprodil ic group (P < 0.05). The OD value of pERK1/2 and pElk-1 positive bands in ifenprodil ic group attenuated generally. The pElk-1 positive bands of caudate putamen and MrD almost disappeared in ifenprodil ic group. CONCLUSION: NR2B is essential for the formation of long-term memory, reconsolidation of Y-maze memory. The deactivation of NR2B by ifenprodil will impair these courses. Meanwhile, the deactivation of NR2B attenuates pERK1/2 and pElk-1 expression of learning and memory related regions after Y-maze learning and memory reconsolidation test. In MrD and caudate putamen, the pElk-1 expression are completely blocked by ifenprodil after memory reconsolidation test.


Asunto(s)
Reacción de Prevención/fisiología , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Memoria/fisiología , Receptores de N-Metil-D-Aspartato/metabolismo , Proteína Elk-1 con Dominio ets/metabolismo , Animales , Dimetilsulfóxido/farmacología , Masculino , Aprendizaje por Laberinto/fisiología , Piperidinas/farmacología , Ratas , Ratas Sprague-Dawley
13.
Artículo en Chino | MEDLINE | ID: mdl-16335394

RESUMEN

OBJECTIVE: To analyze the causes and the clinical characteristics of the neonatal inspiratory dyspnea; so to raise the diagnosis and cure rate of the disease. METHODS: Eleven new born infants with severe inspiratory dyspnea were investigated from March, 2001 to June, 2004 in Shenzhen children's hospital. Six infants were male and 5 were female. The average age was 7.2 days ( range from 8 hours to 28 days). Four cases were hospitalized with trachea intubation. Three of them can not cry, and 2 cases were diagnosed as bilateral vocal cord paralysis, 1 case as multiple cranial nerve palsy with direct laryngoscopy. Two cases couldn't drink milk continuously and accompanied with deteriorated inspiratory dyspnea, and were diagnosed as congenital adenoid hypertrophy and neonatal rhinitis respectively with compute tomography and magnetic resonance imaging. Among the 6 cases with persistent inspiratory dyspnea, four of them were diagnosed as congenital laryngocele by direct laryngoscope, one case was diagnosed as subglottic stenosis by tracheoscopy and one case was confirmed to be thoracic tracheostenosis when tracheotomy performed. RESULTS: Four congenital laryngoceles and one case congenital adenoid hypertrophy were cured with surgery. Two bilateral vocal cord paralysies and one case of subglottic stenosis received tracheotomy. One neonatal rhinitis case applied 0.25% ephedrine. One case of thoracal tracheostenosis died. The parents of the infant with multiple cranial nerve palsy refused to accept any treatment. CONCLUSIONS: The laryngoscope examination is recommended for patients with neonatal inspiratory dyspnea. It is necessary for patients with persistent dyspnea to be examined by tracheoscopy as early as possible.


Asunto(s)
Disnea/etiología , Disnea/terapia , Disnea/diagnóstico , Femenino , Humanos , Recién Nacido , Laringoscopía , Masculino
14.
Lin Chuang Er Bi Yan Hou Ke Za Zhi ; 19(22): 1015-6, 2005 Nov.
Artículo en Chino | MEDLINE | ID: mdl-16463762

RESUMEN

OBJECTIVE: To evaluate the correlation between adenoidal-nasopharyngeal ratio (AN ratio) and tympanogram/eustachian tube function in children. METHOD: A prospective clinical study from February 2004 to October 2004 was carried out. A total of 120 children with adenoids hypertrophy and 20 normal children were examined. The relationship between AN ratio and middle-ear pressure was evaluated, the eustachian tube function was compared between the children with adenoids hypertrophy and the normal. RESULT: (1) Middle ear pressures were negative related to the AN ratio (r = -0.41, P < 0.05); (2) the eustachian tube function of the children with adenoids hypertrophy was worse than the normal; (3) the relation between the eustachian tube function and the AN ratio was not statistical difference. CONCLUSION: Eustachian tube dysfunction caused by adenoids hypertrophy is the etiologic factor of secretory otitis media.


Asunto(s)
Tonsila Faríngea/patología , Trompa Auditiva/fisiopatología , Otitis Media con Derrame , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Pruebas Auditivas , Humanos , Hipertrofia , Masculino , Otitis Media con Derrame/patología , Otitis Media con Derrame/fisiopatología , Estudios Prospectivos
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