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1.
Nano Lett ; 23(17): 8171-8179, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37638840

RESUMO

Despite its important role in understanding ultrafast spin dynamics and revealing novel spin/orbit effects, the mechanism of the terahertz (THz) emission from a single ferromagnetic nanofilm upon a femtosecond laser pump still remains elusive. Recent experiments have shown exotic symmetry, which is not expected from the routinely adopted mechanism of ultrafast demagnetization. Here, by developing a bidirectional pump-THz emission spectroscopy and associated symmetry analysis method, we set a benchmark for the experimental distinction of the THz emission induced by various mechanisms. Our results unambiguously unveil a new mechanism─anomalous Nernst effect (ANE) induced THz emission due to the ultrafast temperature gradient created by a femtosecond laser. Quantitative analysis shows that the THz emission exhibits interesting thickness dependence where different mechanisms dominate at different thickness ranges. Our work not only clarifies the origin of the ferromagnetic-based THz emission but also offers a fertile platform for investigating the ultrafast optomagnetism and THz spintronics.

2.
BMC Public Health ; 23(1): 2507, 2023 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-38097968

RESUMO

BACKGROUND: Inflammatory bowel disease (IBD) is a global health concern with varying levels and trends across countries and regions. Understanding these differences is crucial for effective prevention and treatment strategies. METHODS: Using data from the 2019 Global Burden of Disease study, we examine IBD incidence, mortality, and disability-adjusted life years (DALYs) rates in 198 countries from 1990 to 2019. To assess changes in the burden of IBD, estimated annual percentage changes (EAPC) were calculated, and a Bayesian age-period-cohort model was used to predict the future 30-year trends of IBD. RESULTS: In 2019, there were 405,000 new IBD cases globally (95% uncertainty interval (UI) 361,000 to 457,000), with 41,000 deaths (95% UI 35,000 to 45,000) and 1.62million DALYs (95% UI 1.36-1.92million). The global age-standardized incidence rate in 2019 was 4.97 per 100,000 person-years (95% UI 4.43 to 5.59), with a mortality rate of 0.54 (95% UI 0.46 to 0.59) and DALYs rate of 20.15 (95% UI 16.86 to 23.71). From 1990 to 2019, EAPC values for incidence, mortality, and DALYs rates were - 0.60 (95% UI - 0.73 to - 0.48), - 0.69 (95% UI - 0.81 to - 0.57), and - 1.04 (95% UI - 1.06 to - 1.01), respectively. Overall, the burden of IBD has shown a slow decline in recent years. In SDI stratification, regions with higher initial SDI (high-income North America and Central Europe) witnessed decreasing incidence and mortality rates with increasing SDI, while regions with lower initial SDI (South Asia, Oceania, and Latin America) experienced a rapid rise in incidence but a decrease in mortality with increasing SDI. Predictions using a Bayesian model showed lower new cases and deaths from 2020 to 2050 than reference values, while the slope of the predicted incidence-time curve closely paralleled that of the 2019 data. CONCLUSION: Increasing cases, deaths, and DALYs highlight the sustained burden of IBD on public health. Developed countries have stabilized or declining incidence rates but face high prevalence and societal burden. Emerging and developing countries experience rising incidence. Understanding these changes aids policymakers in effectively addressing IBD challenges in different regions and economic contexts.


Assuntos
Carga Global da Doença , Doenças Inflamatórias Intestinais , Humanos , Teorema de Bayes , Anos de Vida Ajustados por Qualidade de Vida , Prevalência , Incidência , Saúde Global , Doenças Inflamatórias Intestinais/epidemiologia
3.
BMC Pregnancy Childbirth ; 22(1): 110, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35144595

RESUMO

BACKGROUND: Bilateral simultaneous fallopian tubal pregnancy is one of the rarest forms of ectopic pregnancy. Due to the lack of unique features and clinical presentation to distinguish bilateral from unilateral ectopic pregnancy, challenges the diagnosis. CASE REPORT: A 27-year-old Asian woman presented with pelvic pain and vaginal bleeding. Pelvic transvaginal ultrasound showed fluid in Douglas Pouch and posterior fornix puncture revealed unclotted blood. Laparoscopic examination unveiled bilateral ectopic pregnancy with two corpus luteum visible in the right ovary, suggesting a double spontaneous unilateral ovulation. Bilateral fallopian tube fenestration and embryo extraction were performed to preserve fertility. CONCLUSION: Diagnosis of bilateral tubal pregnancy is difficult during preoperative ultrasound examination and careful examination during laparoscopic inspection of the whole pelvic cavity to avoid missed diagnosis.


Assuntos
Corpo Lúteo/diagnóstico por imagem , Tubas Uterinas/cirurgia , Ovulação , Gravidez Tubária/diagnóstico , Gravidez Tubária/patologia , Gravidez Tubária/cirurgia , Adulto , Feminino , Humanos , Laparoscopia/métodos , Gravidez , Doenças Raras/diagnóstico , Doenças Raras/patologia , Doenças Raras/cirurgia , Resultado do Tratamento
4.
Phys Rev Lett ; 117(24): 247201, 2016 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-28009198

RESUMO

The anomalous Nernst effect (ANE) and the spin Seebeck effect (SSE) in spin caloritronics are two of the most important mechanisms to manipulate the spin-polarized current and pure spin current by thermal excitation. While the ANE in ferromagnetic metals and the SSE in magnetic insulators have been extensively studied, a recent theoretical work suggests that the signals from the thermal Hall effect (THE) have field dependences indistinguishable from, and may even overwhelm, those of the ANE and SSE. Therefore, it is vital to investigate the contribution of the THE in the ANE and SSE. In this work, we systematically study the THE in a ferromagnetic metal, Permalloy (Py), and magnetic insulator, an yttrium iron garnet (YIG), by using different Seebeck coefficients between electrodes and contact wires. Our results demonstrate that the contribution of the THE by the thermal couple effect in the Py and YIG is negligibly small if one includes the thickness dependence of the Seebeck coefficient. Thus, the spin-polarized current in the ANE and the pure spin current in the SSE remain indispensable for exploring spin caloritronics phenomena.

5.
BMC Psychol ; 12(1): 343, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38863021

RESUMO

Does social media alleviate or exacerbate loneliness? Past research has shown mixed results regarding the relationship between social media usage and loneliness among younger and older adults. Unlike younger individuals, older adults may decrease their loneliness through social media interactions. Additionally, previous research has indicated that the link between social media use and loneliness can vary depending on one's shy tendency. Therefore, this study aims to explore the relationship between individuals' social media use and loneliness while considering age and shyness tendency as moderating variables. The study employed a questionnaire survey conducted through convenience sampling, resulting in 234 valid responses from participants in Northern Taiwan. Among them, 113 were college students (aged 18 to 25, average age 19.40), and 121 were older adults (aged 50 to 82, average age 60.81). Using hierarchical regression analysis, results indicated that (1) age moderates the relationship between personal social media use and loneliness. Minimal differences were observed among younger individuals, but among older adults, increased social media usage time was associated with a significant reduction in loneliness. (2) Shyness tendency moderate the relationship between personal social media use and loneliness. Individuals with higher shyness tendency experience an increase in loneliness as their social media usage time lengthens.


Assuntos
Solidão , Timidez , Mídias Sociais , Humanos , Solidão/psicologia , Mídias Sociais/estatística & dados numéricos , Masculino , Feminino , Idoso , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Adolescente , Idoso de 80 Anos ou mais , Taiwan , Fatores Etários , Inquéritos e Questionários
6.
Onco Targets Ther ; 17: 41-44, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38298550

RESUMO

Burkitt lymphoma is a highly invasive non-Hodgkin lymphoma. Sporadic Burkitt's lymphoma is commonly found in the abdomen. However, Burkitt lymphoma infiltrating the uterus is uncommon in occurrence. We report the results of 18F-FDG PET/CT examination of a 36-year-old woman. The report indicates that in addition to the strong uptake of FDG imaging agent in the uterus, bilateral cervical and abdominal lymph nodes also have strong activity. At the same time, it was also found that bilateral small breast nodules, sacral canal and multiple bones in the whole body showed a radiation uptake pattern similar to that of the uterus. 18F-FDG PET/CT imaging can help determine the extent of the disease and the affected body area, which is helpful to guide the treatment decision. This case report shows the application of 18F-FDG PET/CT imaging in the diagnosis, staging and post-treatment evaluation of Burkitt lymphoma of the uterus. It provides very useful information for clinicians and helps to improve the accuracy of diagnosis and treatment effect.

7.
Auris Nasus Larynx ; 50(2): 235-240, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35922270

RESUMO

OBJECTIVE: This paper correlated the Meniere attack with meteorological parameters i.e. atmospheric pressure, temperature, relative humidity and rainfall, to investigate which parameters that trigger the Meniere attack. METHODS: During the past three years, totally 283 (2015), 351 (2016) and 319 (2017) patients with Meniere's disease (MD) were encountered at a clinic of the university hospital, accounting for 13%, 17% and 16% incidence in relation to overall annual neurotological cases, respectively. The onset of Meniere attack was then correlated with meteorological parameters. RESULTS: The mean seasonal incidence of Meniere attack in relation to overall seasonal neurotological cases in 2015-2017 were 14.8 ± 2.8% (spring), 17.5 ± 2.2% (summer), 16.0 ± 1.8 % (autumn) and 12.8 ± 2.0% (winter), indicating that summer season had a higher incidence of Meniere attacks than winter season. Onset of Meniere attacks correlated significantly with the atmospheric pressure (r = -0.4484, p = 0.0061) and temperature (r = 0.4736, p = 0.0035), and the atmospheric pressure was highly negatively correlated with the temperature (r = -0.9421, p < 0.0001). In contrast, no correlation was identified between the onset of Meniere attacks and relative humidity or rainfall. The atmospheric pressure in the same month with typhoon compared with that without typhoon revealed a median reduction of 13.1 hectopascal. CONCLUSION: Atmospheric pressure and temperature are correlated with the onset of Meniere attack. Summer season has a higher incidence of Meniere attack than winter season, likely because low atmospheric pressure in summer may aggravate endolymphatic hydrops, especially when accompanied by typhoons in the northwest Pacific region.


Assuntos
Doença de Meniere , Humanos , Doença de Meniere/epidemiologia , Temperatura , Pressão Atmosférica , Estações do Ano , Fenômenos Fisiológicos Respiratórios
8.
Adv Sci (Weinh) ; 10(28): e2301493, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37559172

RESUMO

The metal-semiconductor heterojunction is imperative for the realization of electrically driven nanolasers for chip-level platforms. Progress in developing such nanolasers has hitherto rarely been realized, however, because of their complexity in heterojunction fabrication and the need to use noble metals that are incompatible with microelectronic manufacturing. Most plasmonic nanolasers lase either above a high threshold (101 -103 MW cm-2 ) or at a cryogenic temperature, and lasing is possible only after they are removed from the substrate to avoid the large ohmic loss and the low modal reflectivity, making monolithic fabrication impossible. Here, for the first time, record-low-threshold, room-temperature ultraviolet (UV) lasing of plasmon-coupled core-shell nanowires that are directly grown on silicon is demonstrated. The naturally formed core-shell metal-semiconductor heterostructure of the nanowires leads to a 100-fold improvement in growth density over previous results. This unprecedentedly high nanowire density creates intense plasmonic resonance, which is outcoupled to the resonant Fabry-Pérot microcavity. By boosting the emission strength by a factor of 100, the hybrid photonic-plasmonic system successfully facilitates a record-low laser threshold of 12 kW cm-2 with a spontaneous emission coupling factor as high as ≈0.32 in the 340-360 nm range. Such architecture is simple and cost-competitive for future UV sources in silicon integration.

9.
Front Med (Lausanne) ; 9: 840795, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35355611

RESUMO

A 62-year-old female patient with pathologically confirmed left lung small cell neuroendocrine carcinoma. The patient was referred to our positron emission tomography (PET)/CT center to look for possible metastatic diseases. After fasting for 8 h, the fasting blood glucose level of the patient was 7.1 mmol/L. The patient was intravenously injected with a 6.42 mCi (238 MBq) 18F-fluorodeoxyglucose (FDG) imaging agent. After the patient rested for 1 h, we scanned the patient with SIEMENS Biograph mCT 64 PET/CT camera. In addition to lung tumors and lymph node diseases, abnormal tracer uptake in the patient's thyroid was also found. PET/CT also showed situs inversus totalis of the patient, including the dextrocardia, liver on the left side, stomach, and spleen on the right side of the patient's body. The identification of anatomical variations and abnormalities by PET/CT imaging is very important to develop the best treatment for lung cancer.

10.
Front Pharmacol ; 13: 1010879, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36188614

RESUMO

Background: NPM1 is highly expressed in a variety of solid tumors and promotes tumor development. However, there are few comprehensive studies on NPM1 analysis in gastrointestinal cancer. Methods: We used bioinformatics tools to study the expression difference of NPM1 between gastrointestinal cancer and control group, and analyzed the relationship between its expression level and the diagnosis, prognosis, functional signaling pathway, immune infiltration, m6A and cuproptosis related genes of gastrointestinal cancer. At the same time, the expression difference of NPM1 between esophageal carcinoma (ESCA) samples and control samples was verified by in vitro experiments. Results: NPM1 was overexpressed in gastrointestinal cancer. In vitro experiments confirmed that the expression of NPM1 in ESCA samples was higher than that in normal samples. The expression of NPM1 has high accuracy in predicting the outcome of gastrointestinal cancer. The expression of NPM1 is closely related to the prognosis of multiple gastrointestinal cancers. Go and KEGG enrichment analysis showed that NPM1 co-expressed genes involved in a variety of biological functions. NPM1 expression is potentially associated with a variety of immune cell infiltration, m6A and cuproptosis related genes in gastrointestinal cancers. Conclusion: NPM1 can be used as a diagnostic and prognostic marker of gastrointestinal cancer, which is related to the immune cell infiltration and the regulation of m6A and cuproptosis.

11.
Ear Nose Throat J ; : 1455613211044225, 2021 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-34605286

RESUMO

Kikuchi-Fujimoto disease (KFD) is a self-limited disease that is more common in young Asian women. Typical presentations included fever and cervical lymphadenopathy. The etiology of KFD is unknown, and diagnosis is based mainly on lymph node biopsy. KFD has been reported to be associated with Mycoplasma pneumoniae infection. However, the role of antibiotic treatment is unclear. We reported 2 cases of KFD associated with Mycoplasma pneumoniae infection and were successfully treated with a macrolide.

12.
Front Cell Dev Biol ; 9: 715883, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34708035

RESUMO

Background: Hexokinase 2 not only plays a role in physiological function of human normal tissues and organs, but also plays a vital role in the process of glycolysis of tumor cells. However, there are few comprehensive studies on HK2 in esophageal carcinoma (ESCA) needs further study. Methods: Oncomine, Tumor Immune Estimation Resource (TIMER), The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) database were used to analyze the expression differences of HK2 in Pan-cancer and ESCA cohort, and to analyze the correlation between HK2 expression level and clinicopathological features of TCGA ESCA samples. GO/KEGG, GGI, and PPI analysis of HK2 was performed using R software, LinkedOmics, GeneMANIA and STRING online tools. The correlation between HK2 and ESCA immune infiltration was analyzed TIMER and TCGA ESCA cohort. The correlation between HK2 expression level and m6A modification of ESCA was analyzed by utilizing TCGA ESCA cohort. Results: HK2 is highly expressed in a variety of tumors, and its high expression level in ESCA is closely related to the weight, cancer stages, tumor histology and tumor grade of ESCA. The analysis results of GO/KEGG showed that HK2 was closely related to cell adhesion molecule binding, cell-cell junction, ameboidal-type cell migration, insulin signaling pathway, hif-1 signaling pathway, and insulin resistance. GGI showed that HK2 associated genes were mainly involved in the glycolytic pathway. PPI showed that HK2 was closely related to HK1, GPI, and HK3, all of which played an important role in tumor proliferation. The analysis results of TIMER and TCGA ESCA cohort indicated that the HK2 expression level was related to the infiltration of various immune cells. TCGA ESCA cohort analyze indicated that the HK2 expression level was correlated with m6A modification genes. Conclusion: HK2 is associated with tumor immune infiltration and m6A modification of ESCA, and can be used as a potential biological target for diagnosis and therapy of ESCA.

13.
ACS Omega ; 5(19): 10725-10730, 2020 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-32455191

RESUMO

Excitons in monolayer transition metal dichalcogenides (TMDs) have exceptionally large binding energies and dominate the optical properties of materials. Exploring the relaxation behavior of excitons is crucial for understanding the fundamental physics as well as the performance of TMD-based optoelectronic devices. However, ultrafast carrier dynamics is sensitive to the structural defects and surface conditions of TMDs, depending on the growth or transfer process. Here, we utilized pump-probe transient absorption (TA) spectroscopy with a white-light probe to investigate the dynamics of excitons in monolayer MoS2 synthesized by the metal sulfurization method. The sulfurization method was used for the fabrication of large-scale, continuous, and uniform thin films with a controllable number of layers. The excitation dynamics of the wafer-size monolayer MoS2 is found to be comparable to that of monolayer MoS2 flakes grown by chemical vapor deposition (CVD). The dominant processes of carrier relaxation in the monolayer MoS2 are exciton-exciton annihilation (hundreds of femtoseconds), the trapping of the excitons by surface states (a few picoseconds), and interband carrier-phonon scattering (tens of picoseconds). Moreover, the induced absorption due to mid-gap defects, which is often observed for samples fabricated by growth methods, such as CVD, is not observed for our continuous and uniform monolayer films. Understanding the charge carrier dynamics of the exciton in the scalable and uniform monolayer MoS2 can provide physical insights that are valuable in the design and development of complex 2D devices.

14.
Chin J Dent Res ; 23(4): 297-307, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33491362

RESUMO

Ideally, orthognathic surgery is indicated to treat skeletal Class III malocclusion with severe open bite in adults. In this borderline case, however, camouflage treatment without any skeletal anchorage was chosen. This report describes the orthodontic treatment of a 23-year-old man who presented with multiple orthodontic problems including severe open bite of the anterior and posterior teeth up to the first molars, bilateral posterior crossbite, bilateral Class III molar relationship, severe crowding, increased vertical dimension, and dental and facial midline deviation. The treatment included the extraction of four wisdom teeth, uprighting and distalisation of the mandibular arch with molar intrusion using curved NiTi wires with intermaxillary elastics. After 36 months of treatment, satisfactory improvements in the vertical overlap, horizontal overlap and sagittal malocclusion were achieved. The design of the mechanical system used in this case confirmed stable results at the 4-year follow-up.


Assuntos
Má Oclusão , Mordida Aberta , Procedimentos de Ancoragem Ortodôntica , Adulto , Cefalometria , Seguimentos , Humanos , Masculino , Mandíbula , Mordida Aberta/terapia , Técnicas de Movimentação Dentária , Adulto Jovem
15.
ACS Appl Mater Interfaces ; 10(29): 24733-24738, 2018 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-29969003

RESUMO

We demonstrated the top-gate transistors composed of monolayer MoS2 grown on three-layer alloys Mo xW1- xS2 prepared by sequential sulfurization of predeposited transition metal films. The elemental mapping of the alloy indicates a uniform distribution of both cations Mo and W in the grown samples. Surprisingly, we find that the drain current of transistors could be enhanced by 2 orders of magnitude as the composition of Mo increases, whereas the gate-controlled current modulation turns bipolar and ultimately vanishes. These features might originate from the formation of in-gap defect states, with modest activation energy for transport and moderate hopping probability for current conduction, or a reduced electronic band gap of the conducting channel because of strain.

16.
Otol Neurotol ; 37(5): 428-33, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27093028

RESUMO

OBJECTIVE: This study applied an inner ear test battery in patients with secondary hydrops after acoustic trauma to assess the inner ear deficits. STUDY DESIGN: Retrospective study. SETTING: University hospital. METHODS: Twenty patients with secondary hydrops after acoustic trauma were assigned to Group A. The interval between noise exposure and the testing time varied from 1 month to 3 years (median 3 months). Another 20 patients without progressive hearing loss for at least 3 years after acoustic trauma were assigned to Group B. There were no significant differences between the two groups in terms of age, sex, laterality, and noise source. Before treatment, all patients received audiometry, and caloric, ocular vestibular-evoked myogenic potential (VEMP), and cervical VEMP (cVEMP) tests. RESULTS: Percentages of abnormal mean hearing level (MHL), cVEMP test, oVEMP test, and caloric test were 75%, 75%, 61%, and 43% in Group A, and 35%, 57%, 61%, and 39% in Group B, respectively. Both groups exhibited a significantly declining sequence in inner ear function. Comparison of the abnormalities in the inner ear test battery between Groups A and B revealed a significant difference in percentages of abnormal MHL, but not in those of abnormal cVEMP, oVEMP, and caloric tests. CONCLUSION: Secondary hydrops after acoustic trauma occurs mainly on the cochlear part, but less on the vestibular part probably because previous acoustic trauma, i.e., firearms have severely damaged the vestibular partition.


Assuntos
Hidropisia Endolinfática/etiologia , Hidropisia Endolinfática/fisiopatologia , Perda Auditiva Provocada por Ruído/complicações , Perda Auditiva Provocada por Ruído/fisiopatologia , Adulto , Técnicas de Diagnóstico Otológico , Hidropisia Endolinfática/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Potenciais Evocados Miogênicos Vestibulares/fisiologia , Adulto Jovem
17.
Arch Dis Child ; 104(9): 879, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-29858271
18.
Clin Rheumatol ; 33(1): 119-23, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24077913

RESUMO

This study aims to investigate the incidence of hepatitis B virus (HBV) reactivation in inflammatory arthritis (IA) patients with HBV infection using anti-tumor necrosis factor (TNF) agents and evaluate the efficacy of antiviral therapy in reducing the risk of viral reactivation in chronic HBV infection. IA patients using anti-TNF agents from six centers were enrolled. Their HBV infection conditions and ALT and HBV-DNA levels were monitored periodically. Among the six chronic hepatitis B patients, HBV reactivation was found in two patients without antivirus prophylaxis and no viral replication was detected in the other four patients with antivirus prophylaxis. In the 31 inactive carriers, the increase of viral load was detected in 6 of 22 (27.3 %) patients without antiviral prophylaxis, and there was no viral reactivation in the other 9 patients with antiviral prophylaxis. HBV reactivation was not found in the 50 patients with resolved HBV infection. It is suggested that anti-TNF therapy might increase the risk of HBV reactivation in patients with chronic HBV infection, and antiviral prophylaxis could effectively decrease the risk. Anti-TNF agents seem to be safe in patients with resolved HBV infection.


Assuntos
Artrite Reumatoide/terapia , Hepatite B/terapia , Inflamação/terapia , Espondilite Anquilosante/terapia , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Adolescente , Adulto , Anticorpos Monoclonais/administração & dosagem , Antirreumáticos/uso terapêutico , Artrite Reumatoide/complicações , Artrite Reumatoide/imunologia , Etanercepte , Feminino , Hepatite B/complicações , Hepatite B/imunologia , Vírus da Hepatite B , Humanos , Imunoglobulina G/administração & dosagem , Inflamação/fisiopatologia , Infliximab , Masculino , Pessoa de Meia-Idade , Receptores do Fator de Necrose Tumoral/administração & dosagem , Espondilite Anquilosante/complicações , Espondilite Anquilosante/imunologia , Resultado do Tratamento , Carga Viral , Adulto Jovem
19.
Steroids ; 78(5): 508-12, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23485688

RESUMO

A series of bufalin 3-nitrogen-containing-ester derivatives (2-6) were designed, synthesized, and evaluated for their proliferation inhibition activities against human cervical epithelial adenocarcinoma (HeLa) and non-small-cell lung cancer (A549) cell lines. The structure-activity relationships (SARs) of this new series were described in this paper. Cytotoxicity data revealed that C3 moiety had important influence on cytotoxic activity. On two cell lines, the bufalin-3-piperidinyl-4-carboxylate compound 2 (IC50 values on HeLa and A549 cell lines were 0.76 nM and 0.34 nM, respectively) displayed a significant cytotoxic potency compared to the parent compound bufalin.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Bufanolídeos/química , Bufanolídeos/farmacologia , Nitrogênio/química , Antineoplásicos/síntese química , Bufanolídeos/síntese química , Técnicas de Química Sintética , Ésteres , Células HeLa , Humanos , Concentração Inibidora 50 , Relação Estrutura-Atividade
20.
Biomaterials ; 31(12): 3384-94, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20149435

RESUMO

A pH-sensitive nanoparticle (NP) system composed of chitosan and poly(gamma-glutamic acid) was prepared for the oral delivery of insulin. The biodistribution study in a rat model showed that some of the orally administered NPs were retained in the stomach for a long duration, which might lead to the disintegration of NPs and degradation of insulin. To overcome these problems, we freeze-dried NPs and filled them in an enteric-coated capsule. The small angle X-ray scattering (SAXS) profiles indicated that the freeze-drying process did not significantly disrupt the internal structure of NPs; additionally, their pH-sensitivity was preserved and the insulin release was pH-dependent. The results obtained in the native PAGE analysis indicated that the released insulin molecules were neither fragmented nor aggregated. Upon oral administration, the enteric-coated capsule remained intact in the acidic environment of the stomach, but dissolved rapidly in the proximal segment of the small intestine. Consequently, all the NPs loaded in the capsule were brought into the small intestine, thus enhancing the intestinal absorption of insulin and providing a prolonged reduction in blood glucose levels. The relative bioavailability of insulin was found to be approximately 20%. These results suggest that the formulation developed in the study might be employed as a potential approach for the oral delivery of insulin.


Assuntos
Quitosana/administração & dosagem , Liofilização , Insulina/administração & dosagem , Nanopartículas , Administração Oral , Animais , Diabetes Mellitus Experimental/tratamento farmacológico , Eletroforese em Gel de Poliacrilamida , Insulina/uso terapêutico , Masculino , Ratos , Ratos Wistar , Espalhamento de Radiação , Solubilidade
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