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1.
Bioconjug Chem ; 35(3): 277-285, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38417023

RESUMO

Peptides and proteins undergo crucial modifications to alter their physicochemical properties to expand their applications in diverse fields. Various techniques, such as unnatural amino acid incorporation, enzyme catalysis, and chemoselective methods, have been employed for site-selective peptide and protein modification. While traditional methods remain valuable, advancement in host-guest chemistry introduces innovative and promising approaches for the selective modification of peptides and proteins. Macrocycles exhibit robust binding affinities, particularly with natural amino acids, which facilitates their use in selectively binding to specific sequences. This distinctive property endows macrocycles with the potential for modification of target peptides and proteins. This review provides a comprehensive overview of strategies utilizing macrocycles for the selective modification of peptides and proteins. These strategies unlock new possibilities for constructing antibody-drug conjugates and stabilizing volatile medications.


Assuntos
Peptídeos , Proteínas , Peptídeos/química , Proteínas/química , Aminoácidos/química , Processamento de Proteína Pós-Traducional
2.
Ann Hematol ; 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38761184

RESUMO

Bruton's tyrosine kinase inhibitors (BTKi) exhibit superior efficacy in relapsed/refractory primary central nervous system lymphoma (PCNSL), but few studies have evaluated patients with newly diagnosed PCNSL, and even fewer studies have evaluated differences in efficacy between treatment with BTKi and traditional chemotherapy. This study retrospectively analyzed the clinical characteristics of 86 patients with PCNSL and identified predictors of poor prognosis for overall survival (OS). After excluding patients who only received palliative care, 82 patients were evaluated for efficacy and survival. According to the induction regimen, patients were divided into the traditional chemotherapy, BTKi combination therapy, and radiotherapy groups; the objective response rates (ORR) of the three groups were 71.4%, 96.2%, and 71.4% (P = 0.037), respectively. Both median progression-free survival and median duration of remission showed statistically significant differences (P = 0.019 and P = 0.030, respectively). The median OS of the BTKi-containing therapy group was also longer than that of the traditional chemotherapy group (not reached versus 47.8 (32.5-63.1) months, P = 0.038).Seventy-one patients who achieved an ORR were further analyzed, and achieved an ORR after four cycles of treatment and maintenance therapy had prolonged OS (P = 0.003 and P = 0.043, respectively). In conclusion, survival, and prognosis of patients with newly diagnosed PCNSL are influenced by the treatment regimen, with the BTKi-containing regimen showing great potential.

3.
Phys Rev Lett ; 131(5): 050801, 2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37595225

RESUMO

Permitting a more precise measurement to physical quantities than the classical limit by using quantum resources, quantum metrology holds a promise in developing many revolutionary technologies. However, the noise-induced decoherence forces its superiority to disappear, which is called no-go theorem of noisy quantum metrology and constrains its application. We propose a scheme to overcome the no-go theorem by Floquet engineering. It is found that, by applying a periodic driving on the atoms of the Ramsey spectroscopy, the ultimate sensitivity to measure their frequency characterized by quantum Fisher information returns to the ideal t^{2} scaling with the encoding time whenever a Floquet bound state is formed by the system consisting of each driven atom and its local noise. Combining with the optimal control, this mechanism also allows us to retrieve the ideal Heisenberg-limit scaling with the atom number N. Our result gives an efficient way to avoid the no-go theorem of noisy quantum metrology and to realize high-precision measurements.

4.
Phys Rev Lett ; 127(8): 083602, 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34477431

RESUMO

As a genuine many-body entanglement, spin squeezing (SS) can be used to realize the highly precise measurement beyond the limit constrained by classical physics. Its generation has attracted much attention recently. It was reported that N two-level systems (TLSs) located near a one-dimensional waveguide can generate SS by using the mediation effect of the waveguide. However, a coherent driving on each TLS is used to stabilize the SS, which raises a high requirement for experiments. We here propose a scheme to generate stable SS resorting to neither the spin-spin coupling nor the coherent driving on the TLSs. Incorporating the mediation role of the common waveguide and the technique of squeezed-reservoir engineering, our scheme exhibits the advantages over previous ones in the scaling relation of the SS parameter with the number of the TLSs. The long-range correlation feature of the generated SS along the waveguide in our scheme may endow it with certain superiority in quantum sensing, e.g., improving the sensing efficiency of spatially unidentified weak magnetic fields.

5.
Zhongguo Zhong Yao Za Zhi ; 46(19): 5027-5037, 2021 Oct.
Artigo em Zh | MEDLINE | ID: mdl-34738398

RESUMO

To obtain the chemical profile of Tibetan medicinal plant ″Bangga″, the present study established the HPLC fingerprint of ″Bangga″ and inferred common chemical constituents of its two original plants, Aconitum tanguticum and A. naviculare by LC-MS. The HPLC analysis was performed on a Kromasil 100 C_8 column(4.6 mm×250 mm, 5 µm) with acetonitrile(A)-0.1% formic acid in water(B) as mobile phase in a gradient elution mode. Besides, the flow rate was set at 1 mL·min~(-1) and the column temperature was 35 ℃. The detection wavelength was set at 255 nm and the injection volume was 10 µL. Seventeen batches of ″Bangga″ samples were analyzed and the HPLC fingerprint was established under the above conditions. Similarity evaluation was performed using Similarity Evaluation System for Chromatographic Fingerprint of Traditional Chinese Medicine(2012). As a result, 16 common peaks were selec-ted and the similarity values of 17 batches of ″Bangga″ were in the range of 0.702-0.966. Furthermore, one batch of A. tanguticum and one batch of A. naviculare were analyzed by LC-MS/MS and 74 common compounds were inferred, including 10 phenolic acids, 26 flavonoids, and 38 alkaloids. The established method, with good separation and strong specificity, is simple and feasible, and can be used for the quality control of ″Bangga″ and identification of its two original plants. A. tanguticum and A. naviculare are similar in chemical composition and component content, but are quite different in the content of flavonoids.


Assuntos
Medicamentos de Ervas Chinesas , Plantas Medicinais , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Espectrometria de Massas em Tandem , Tibet
6.
J Virol ; 93(16)2019 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-31167908

RESUMO

Hemoglobin is an important oxygen-carrying protein and plays crucial roles in establishing host resistance against pathogens and in regulating innate immune responses. The hemoglobin subunit beta (HB) is an essential component of hemoglobin, and we have previously demonstrated that the antiviral role of the porcine HB (pHB) is mediated by promoting type I interferon pathways. Thus, considering the high homology between human HB (hHB) and pHB, we hypothesized that hHB also plays an important role in the antiviral innate immunity. In this study, we characterized hHB as a regulatory factor for the replication of RNA viruses by differentially regulating the RIG-I- and MDA5-mediated antiviral signaling pathways. Furthermore, we showed that hHB directly inhibited MDA5-mediated signaling by reducing the MDA5-double-stranded RNA (dsRNA) interaction. Additionally, hHB required hHB-induced reactive oxygen species (ROS) to promote RIG-I-mediated signaling through enhancement of K63-linked RIG-I ubiquitination. Taken together, our findings suggest that hHB is a pleiotropic regulator of RIG-I/MDA5-mediated antiviral responses and further highlight the importance of the intercellular microenvironment, including the redox state, in regulating antiviral innate immune responses.IMPORTANCE Hemoglobin, the most important oxygen-carrying protein, is involved in the regulation of innate immune responses. We have previously reported that the porcine hemoglobin subunit beta (HB) exerts antiviral activity through regulation of type I interferon production. However, the antiviral activities and the underlying mechanisms of HBs originating from other animals have been poorly understood. Here, we identified human HB (hHB) as a pleiotropic regulator of the replication of RNA viruses through regulation of RIG-I/MDA5-mediated signaling pathways. hHB enhances RIG-I-mediated antiviral responses by promoting RIG-I ubiquitination depending on the hHB-induced reactive oxygen species (ROS), while it blocks MDA5-mediated antiviral signaling by suppressing the MDA5-dsRNA interaction. Our results contribute to an understanding of the crucial roles of hHB in the regulation of the RIG-I/MDA5-mediated signaling pathways. We also provide novel insight into the correlation of the intercellular redox state with the regulation of antiviral innate immunity.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Proteína DEAD-box 58/metabolismo , Suscetibilidade a Doenças , Imunidade Inata , Viroses/etiologia , Viroses/metabolismo , Globinas beta/metabolismo , Linhagem Celular , Resistência à Doença , Interações Hospedeiro-Patógeno/imunologia , Humanos , Modelos Biológicos , Proibitinas , Vírus de RNA , Espécies Reativas de Oxigênio/metabolismo , Receptores Imunológicos , Transdução de Sinais , Ubiquitinação , Replicação Viral , Globinas beta/genética
7.
Fa Yi Xue Za Zhi ; 31(6): 428-31, 2015 Dec.
Artigo em Zh | MEDLINE | ID: mdl-27141798

RESUMO

OBJECTIVE: To study the morphological characteristics of femurs of adult human and 11 kinds of adult animals from cattle, horses, pigs, goats, sheep, dogs, cats, rabbits, geese, ducks, chickens, and to establish an effective species identification method among various species. METHODS: The 4 cm mid-diaphyseal segment of the femur from adult human (older than 20 years old) at autopsy was obtained. Addi-tionally, the 4 cm ones from 11 kinds of adult animals were obtained. After decalcification, all femurs were made into slices, and then were observed by optical microscope. The 25 indexes were selected and analyzed by step discriminant analysis according to differences between human and mammal, human and poultry, and human and 11 kinds of animals. RESULTS: The histological structure of bone mineral density of middle part of femur had obvious characteristics among the species. And the morphology and number of osteon showed the trend of obvious biological evolution. There were 11 indexes with significant differences between human and 11 kinds of animals to establish some mathematical models to discriminate all species. The correct discrimination rate was 96.3% between human and mammal. The correct discrimination rate was up to 100% between human and poultry, and was 89.4% among human, mammal and poultry. CONCLUSION: The mathematical models have good correct discrimination rate among human and the other animals, which could be applied in the practical species identification cases.


Assuntos
Fêmur/ultraestrutura , Ósteon/ultraestrutura , Adulto , Animais , Autopsia , Densidade Óssea , Cadáver , Gatos , Bovinos , Galinhas , Análise Discriminante , Cães , Antropologia Forense , Cavalos , Humanos , Ovinos , Especificidade da Espécie , Suínos
8.
ChemMedChem ; 19(17): e202400223, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-38807345

RESUMO

The abnormal aggregation of Aß has been considered one of the primary causative factors for Alzheimer's disease. Diverse molecular entities have been developed to mitigate the formation of toxic Aß aggregates within the brain by inhibiting Aß aggregation. Recognizing that many FDA-approved drugs are derived from natural products, we present a summary of recent discoveries involving natural product molecules with inhibitory effects on Aß aggregation. By consolidating these findings, our review offers researchers a concise overview of the latest advancements in natural product-based interventions for Alzheimer's disease.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Produtos Biológicos , Agregados Proteicos , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Produtos Biológicos/síntese química , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/metabolismo , Humanos , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Agregados Proteicos/efeitos dos fármacos , Estrutura Molecular
9.
Medicine (Baltimore) ; 103(36): e39610, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39252327

RESUMO

BACKGROUND: Obesity, a multifactorial and complex health condition, has emerged as a significant global public health concern. Integrating machine learning techniques into obesity research offers great promise as an interdisciplinary field, particularly in the screening, diagnosis, and analysis of obesity. Nevertheless, the publications on using machine learning methods in obesity research have not been systematically evaluated. Hence, this study aimed to quantitatively examine, visualize, and analyze the publications concerning the use of machine learning methods in obesity research by means of bibliometrics. METHODS: The Web of Science core collection was the primary database source for this study, which collected publications on obesity research using machine learning methods over the last 20 years from January 1, 2004, to December 31, 2023. Only articles and reviews that fit the criteria were selected for bibliometric analysis, and in terms of language, only English was accepted. VOSviewer, CiteSpace, and Excel were the primary software utilized. RESULTS: Between 2004 and 2023, the number of publications on obesity research using machine learning methods increased exponentially. Eventually, 3286 publications that met the eligibility criteria were searched. According to the collaborative network analysis, the United States has the greatest volume of publications, indicating a significant influence on this research. coauthor's analysis showed the authoritative one in this field is Leo Breiman. Scientific Reports is the most widely published journal. The most referenced publication is "R: a language and environment for statistical computing." An analysis of keywords shows that deep learning, support vector machines, predictive models, gut microbiota, energy expenditure, and genome are hot topics in this field. Future research directions may include the relationship between obesity and its consequences, such as diabetic retinopathy, as well as the interaction between obesity and epidemiology, such as COVID-19. CONCLUSION: Utilizing bibliometrics as a research tool and methodology, this study, for the first time, reveals the intrinsic relationship and developmental pattern among obesity research using machine learning methods, which provides academic references for clinicians and researchers in understanding the hotspots and cutting-edge issues as well as the developmental trend in this field to detect patients' obesity problems early and develop personalized treatment plans.


Assuntos
Bibliometria , Aprendizado de Máquina , Obesidade , Humanos , Obesidade/epidemiologia , Pesquisa Biomédica/métodos , Pesquisa Biomédica/tendências
10.
World J Clin Cases ; 12(3): 565-574, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38322474

RESUMO

BACKGROUND: Marginal zone lymphoma (MZL) is an indolent subtype of non-Hodgkin lymphoma (NHL), which is rare clinically with severe rashes as the initial symptom. CASE SUMMARY: This study reports a case of MZL with generalized skin rashes accompanied by pruritus and purulent discharge. First-line treatment with rituximab combined with zanubrutinib had poor effects. However, after switching to obinutuzumab combined with zanubrutinib, the case was alleviated, and the rashes disappeared. CONCLUSION: For patients with advanced stage MZL not benefiting from type I anti-CD20 monoclonal antibody (mAb) combination therapy, switching to a type II anti-CD20 mAb combination regimen may be considered. This approach may provide a new perspective in the treatment of MZL.

11.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 37(2): 162-167, 2019 Apr 01.
Artigo em Zh | MEDLINE | ID: mdl-31168982

RESUMO

OBJECTIVE: The purpose of this study is to investigate the potential effects of sclerostin (SOST) on the biological funtions and related mechanisms of cementoblasts under mechanical stress. METHODS: OCCM-30 cells were treated with varying doses of SOST (0, 25, 50, and 100 ng·mL⁻¹) and were loaded with uniaxial compressive stress (2 000 µ strain with a frequency of 0.5 Hz) for six hours. Western blot was utilized to detect the expressions of ß-catenin, p-smad1/5/8, and smad1/5/8 proteins. Alkaline phosphatase (ALP) activity was determined, and reverse transcription polymerase chain reaction was used to measure the expressions of runt-related transcription factor 2 (Runx-2), osteocalcin (OCN), bone sialoproteins (BSP), receptor activator of NF-κB ligand (RANKL) and osteoprotegerin (OPG) mRNA. RESULTS: The expression of p-smad
1/5/8 was significantly downregulated with increasing SOST. ß-catenin and smad1/5/8 exhibited no difference. ALP activity decreased under mechanical compressive stress with increasing SOST concentrations. Runx-2 expression was reduced with increasing SOST concentrations, and a similar trend was observed for the BSP and OCN expressions. When the SOST concentration was enhanced, RANKL expression gradually increased, whereas the expression of OPG decreased. CONCLUSIONS: Under mechanical comprehensive stress, SOST can adjust the bone morphogenetic protein (BMP) /smad signal pathway. Osteosclerosis inhibits the mineralization of cementoblasts under mechanical compressive stress, which may be achieved by inhibiting the expressions of osteogenesis factors (Runx2, OCN, BSP, and others) and by promoting the ratio of cementoclast-related factors (RANKL/OPG) through BMP signal pathways.


Assuntos
Proteínas Morfogenéticas Ósseas , Cemento Dentário , Proteínas Morfogenéticas Ósseas/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core , Osteocalcina , Proteínas Smad/metabolismo , Estresse Mecânico
12.
ACS Appl Mater Interfaces ; 11(33): 29814-29820, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31340645

RESUMO

A large transition dipole moment is usually pursued by strategies of twisted intramolecular charge transfer (TICT) or planar intramolecular charge transfer (PICT) to obtain obvious Stokes shifts and dramatic color changes with tuning of polarities. However, both strategies have their drawbacks and suffer from fluorescence quenching in solid states. Herein, a ladder-type molecule ISOAA-H with an intramolecular hydrogen bond is designed, which undergoes intramolecular charge transfer and proton shift to harvest a large transition dipole moment under light irradiation. Thanks to its out-of-plane side chains, the intermolecular π-π stacking of backbones is prohibited and solid emission is generated. ISOAA-H exhibits outstanding solvatochromic behavior with polarity changes of solvents or polymer matrixes and is successfully used to detect the microphase separation of polymer blends. These results indicate that a strategy combining the advantages of TICT and PICT is established for environment-sensitive dyes used in both solution and solid state.

13.
Curr Med Sci ; 39(2): 196-203, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31016510

RESUMO

With the intensification of the aging process of the world, Alzheimer's disease (AD), which is the main type of senile dementia, has become a primary problem in the present society. Lots of strategies have been used to prevent and treat AD in animal models and clinical trials, but most of them ended in failure. Panax notoginseng saponins (PNS) contain a variety of monomer compositions which have been separated and identified. Among of the monomer compositions, notoginseng saponin Rg1 (Rg1) accounts for 20% of the cultivation of panax notoginseng roots. And now PNS have been reported to be widely used to treat cardio-cerebrovascular diseases and have neuroprotective effects to restrain the ß-amyloid peptide (Aß)25-35-mediated apoptosis. Moreover, it is reported that PNS could accelerate the growth of nerve cells, increase the length of axons and promote synaptic plasticity. Whether Rg1 can ameliorate the cognitive impairment and the underlying mechanism has not been elucidated. To study the preventive effect of Rg1 on cognitive impairment and the possible mechanism, we established the cognitive impairment model in rats through Aß1-42 (2.6 µg/µL, 5 µL) injection and then treated the rats with Rg1 (25, 50 and 100 mg/kg) administered intragastrically for 4 weeks. We observed that Aß1-42 could induce spatial learning and memory deficits in rats. Simultaneously, Aß1-42 injection also resulted in the reduced neuron number in cornuammonis 1 (CA1) and dentate gyrus (DG) of hippocampus, as well as the increased level of hyperphosphorylated ß-amyloid precursor protein (APP) at Thr668 site with up-regulation of ß-APP cleaving enzyme 1 (BACE1) and presenilin 1 (PS1) and down-regulation of a disintegrin and metalloprotease domain-containing protein 10 (ADAM10) and insulin-degrading enzyme (IDE). Administration of Rg1 effectively rescued the cognitive impairment and neuronal loss, and inhibited the ß-secretase processing of APP through reducing APP-Thr668 phosphorylation and BACE1/PS1 expression, and increasing the expression of ADAM10 and IDE. We concluded that Rg1 might have neuroprotective effects and could promote learning and memory ability, which might be a viable candidate in AD therapy probably through reducing the generation of Aß and increasing the degradation of Aß.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Disfunção Cognitiva/prevenção & controle , Panax notoginseng/química , Fragmentos de Peptídeos/metabolismo , Saponinas/farmacologia , Doença de Alzheimer/metabolismo , Doença de Alzheimer/prevenção & controle , Secretases da Proteína Precursora do Amiloide/metabolismo , Animais , Disfunção Cognitiva/metabolismo , Giro Denteado/efeitos dos fármacos , Giro Denteado/metabolismo , Modelos Animais de Doenças , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Aprendizagem/efeitos dos fármacos , Masculino , Memória/efeitos dos fármacos , Transtornos da Memória/metabolismo , Transtornos da Memória/prevenção & controle , Fármacos Neuroprotetores/farmacologia , Presenilina-1/metabolismo , Ratos , Ratos Sprague-Dawley
14.
Artigo em Inglês | MEDLINE | ID: mdl-26170655

RESUMO

BACKGROUND: The objective of the study is to develop a scoring system for predicting a 90-day re-exacerbation in hospitalized patients with acute exacerbations of chronic obstructive pulmonary disease (AECOPD). METHODS: A total of 176 consecutive hospitalized patients with AECOPD were included. The sociodemographic characteristics, status before acute exacerbation (AE), presentations of and treatment for the current AE, and the re-exacerbation in 90 days after discharge from hospital were collected. RESULTS: The re-exacerbation rate in 90 days was 48.9% (86 out of 176). It was associated with the degree of lung function impairment (Global initiative for chronic Obstructive Lung Disease [GOLD] grades), frequency of AE in the previous year, and parameters of the current AE, including pleural effusion, use of accessory respiratory muscles, inhaled long-acting ß-2-agonists, inhaled corticosteroids, controlled oxygen therapy, noninvasive mechanical ventilation, and length of hospital stay, but was not associated with body mass index, modified Medical Research Council scale, or chronic obstructive pulmonary disease assessment test. A subgroup of ten variables was selected and developed into the re-exacerbation index scoring system (age grades, GOLD grades, AE times in the previous year, pleural effusion, use of accessory respiratory muscles, noninvasive mechanical ventilation, controlled oxygen therapy, inhaled long-acting ß-2-agonists and inhaled corticosteroids, and length of hospital stay). The re-exacerbation index showed good discrimination for re-exacerbation, with a C-statistic of 0.750 (P<0.001). CONCLUSION: A comprehensive assessment integrating parameters of stable chronic obstructive pulmonary disease, clinical presentations at exacerbation, and treatment showed a strong predictive capacity for short-term outcome in patients with AECOPD. Further studies are required to verify these findings.


Assuntos
Técnicas de Apoio para a Decisão , Indicadores Básicos de Saúde , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Idoso , Área Sob a Curva , Progressão da Doença , Feminino , Nível de Saúde , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Doença Pulmonar Obstrutiva Crônica/terapia , Curva ROC , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Fatores de Tempo
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