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1.
Epilepsia ; 64(6): 1541-1553, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36928628

RESUMO

OBJECTIVE: We aim to determine whether automatically detected ripple rate (ADRR) of 10-min scalp electroencephalography (EEG) during slow-wave sleep can be a useful tool for rapid epilepsy differentiation and seizure activity assessment, and we analyze the clinical factors that may affect the scalp ripple rates. METHODS: We retrospectively included 336 patients who underwent long-term video-EEG with a sampling rate ≥1000 Hz, and three groups were established based on their final clinical diagnosis (non-epilepsy; non-active epilepsy [epilepsy being seizure-free for at least 1 year]; and active epilepsy [epilepsy with one or more seizures in the past year]). ADRRs between groups were compared and diagnostic thresholds set according to the maximum of Youden index with the receiver-operating characteristic curve. RESULTS: The 336 patients comprised 49 non-epilepsy and 287 epilepsy patients (95 non-active epilepsy and 192 active epilepsy). The median ADRR of the epilepsy group was significantly greater than in the non-epilepsy group, with a diagnostic threshold of 4.25 /min (specificity 89.8%, sensitivity 47.74%, p<.001). Following stratification by age, the area under the curve was greatest in the 0-20 year subgroup, threshold 4.10 /min (specificity 100%, sensitivity 52.47%, p<.001). Regarding distinguishing active epilepsy from non-active epilepsy patients, the area under the curve was also greatest in patients 0-20 years of age, threshold 13.05/min (specificity 98.36%, sensitivity 35.64%, p<.001). Following stratification by epilepsy type, the diagnostic efficiency was best in children with developmental and epileptic encephalopathies/epileptic encephalopathies (DEEs/EEs) (threshold 5.20/min, specificity 100%, sensitivity 100%) and self-limited focal epilepsies (SeLFEs) (threshold 5.45/min, specificity 80%, sensitivity 100%). Multivariate analysis revealed that the influential factors of ADRRs were age, depth of epileptogenic lesion, and seizure frequency. SIGNIFICANCE: ADRR of scalp EEG can be a rapid and specific method to differentiate epilepsy and evaluate seizure activity. This method is especially suitable for young patients.


Assuntos
Epilepsia , Couro Cabeludo , Criança , Humanos , Estudos Retrospectivos , Epilepsia/diagnóstico , Convulsões/diagnóstico , Eletroencefalografia/métodos
2.
Pharm Res ; 40(10): 2347-2354, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37537423

RESUMO

Solid form screening is a crucial step in new drug development because solid forms of a drug substance significantly affect stability, dissolution and manufacturing processes of its drug products. This perspective introduces solid-state science from a practical standpoint, aiming to reduce knowledge gaps and promote communications among scientists with diverse background. This perspective starts with a concise overview that followed by discussion on timeline and goals of solid form screening. Techniques for solid from identification and characterization are then discussed. Subsequently, the perspective presents commonly used methods in solid form screening and introduces criteria and strategies to effectively select a favorable solid form based on screening results. The last section summarizes current practices in pharmaceutical industries and suggests potential opportunities for future research and development.


Assuntos
Química Farmacêutica , Desenho de Fármacos , Química Farmacêutica/métodos , Cristalização , Desenvolvimento de Medicamentos , Preparações Farmacêuticas
3.
BMC Musculoskelet Disord ; 24(1): 364, 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37161368

RESUMO

BACKGROUND: Currently, there is no consensus on the most appropriate technique for obtaining lateral hip radiographs after cephalomedullary nail (CMN) surgery. The aim of this study was to investigate the distribution of two commonly used postoperative lateral hip radiographic methods (classic lateral view and modified lateral view) and try to find out which one is better suited for this situation. METHODS: A retrospective analysis was conducted on 146 patients who underwent surgical fixation for extracapsular hip fractures between January 2018 and June 2022. The main outcome measured was the angle between the straight part of the CMN and the lag screw/blade on hip lateral X-rays (CMNA). The lateral hip radiographs were categorized into two groups based on different lateral hip radiographic methods. CMNA, patient age, gender, fracture classification based on the 2018 AO classification, nail length (short/long), surgical side (left/right), height, weight, BMI, preoperative waiting time, postoperative imaging interval were collected and compared between the two groups. RESULTS: The distribution trend of CMNA significantly differs between two types of hip joint lateral radiographic methods. Specifically, the classic lateral method exhibits a significantly bimodal and skewed distribution with a median (p25, p75) of -21.6° (-31.2°, -8°), whereas the modified lateral method presents a normal distribution with a mean ± SD of +7.57° ± 14.4°. The difference in the Mean Rank between the classic (47.10) and the modified (102.96) lateral methods is statistically significant (P < 0.001). CONCLUSIONS: The CMNA method is an excellent tool for studying the lateral distribution.We recommend using the modified lateral view as the preferred option for obtaining lateral hip radiographs after CMN surgery due to its superior distribution of CMNA and greater patient-friendliness.


Assuntos
Parafusos Ósseos , Fraturas do Quadril , Humanos , Estudos Retrospectivos , Radiografia , Cuidados Pós-Operatórios , Fraturas do Quadril/diagnóstico por imagem , Fraturas do Quadril/cirurgia
4.
Mol Pharm ; 19(7): 2343-2350, 2022 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-35477294

RESUMO

Amorphous formulations, increasingly employed to deliver poorly soluble drugs, generally contain surfactants to improve wetting and dissolution. These surfactants are often liquids and can potentially increase the mobility of the drug and reduce its stability, but little is known about this effect. Here we investigate the effect of four common nonionic surfactants (Tween 80, Span 80, Triton X-100, and Poloxamer 407) on the crystallization of amorphous nifedipine (NIF). We find that the surfactants significantly enhance the rates of crystal nucleation and growth even at low concentrations, by up to 2 orders of magnitude at 10 wt %. The surfactants tested show similar enhancement effects independent of their structural details and hydrophilic-lipophilic balance (HLB), suggesting that surfactant adsorption at solid/liquid interfaces does not play a major role in crystal nucleation and growth. Importantly, the surfactants accelerate crystal nucleation and growth by a similar factor. This result mirrors the previous finding that a polymer dopant in a molecular glass-former causes similar slowdown of nucleation and growth. These results indicate that nucleation and growth in a deeply supercooled liquid are both mobility-limited, and a dopant mainly functions as a mobility modifier (enhancer or suppressor depending on the dopant). The common surfactants tested are all mobility enhancers and destabilize the amorphous drug, and this negative effect must be managed using stabilizers such as polymers. The effect of surfactants on nucleation can be predicted from the effect on crystal growth and the crystallization kinetics of the pure system, using the same principle previously established for drug-polymer systems. We show how the independently measured nucleation and growth rates enable predictions of the overall crystallization rates.


Assuntos
Nifedipino , Tensoativos , Cristalização , Interações Hidrofóbicas e Hidrofílicas , Nifedipino/química , Polímeros/química , Solubilidade , Tensoativos/química
5.
J Chem Phys ; 157(19): 194502, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36414445

RESUMO

Molecules at a liquid/vapor interface have different organizations and mobilities from those in the bulk. These differences potentially influence the rate of crystal nucleation, but the effect remains imperfectly understood. We have measured the crystal nucleation rates at the surface and in the bulk of amorphous poscaconazole, a rod-like molecule known to have a preferred interfacial orientation. We find that surface nucleation is vastly enhanced over bulk nucleation, by ∼9 orders of magnitude, and selects a different polymorph (II) from bulk nucleation (I). This phenomenon mirrors the recently reported case of D-arabitol and stems from the similarity of anisotropic surface molecular packing to the structure of the surface-nucleating polymorph. In contrast to these two systems, the surface enhancement of nucleation is weaker (though still significant) in acetaminophen and in water and does not select a different polymorph. Together, the systems investigated to date all feature surface enhancement, not suppression, of crystal nucleation, and those showing a polymorphic change feature (1) structural reconstruction at the surface relative to the bulk and (2) existence of a different polymorph that can take advantage of the surface environment to nucleate. These results help predict the effect of a liquid/vapor interface on crystal nucleation and polymorph selection, especially in systems with a large surface/volume ratio, such as atmospheric water and amorphous particles.

6.
J Chem Phys ; 156(14): 144504, 2022 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-35428390

RESUMO

Crystal nucleation rates have been measured in the supercooled melts of two richly polymorphic glass-forming liquids: ROY and nifedipine (NIF). ROY or 5-methyl-2-[(2-nitrophenyl)amino]-3-thiophenecarbonitrile is known for its crystals of red, orange, and yellow colors and many polymorphs of solved structures (12). Of the many polymorphs, ON (orange needles) nucleates the fastest with the runner up (Y04) trailing by a factor of 103 when compared under the same mobility-limited condition, while the other unobserved polymorphs are slower yet by at least 5 orders of magnitude. Similarly, of the six polymorphs of NIF, γ' nucleates the fastest, ß' is slower by a factor of 10, and the rest are slower yet by at least 5 decades. In both systems, the faster-nucleating polymorphs are not built from the lowest-energy conformers, while they tend to have higher energies and lower densities and thus greater similarity to the liquid phase by these measures. The temperature ranges of this study covered the glass transition temperature Tg of each system, and we find no evidence that the nucleation rate is sensitive to the passage of Tg. At the lowest temperatures investigated, the rates of nucleation and growth are proportional to each other, indicating that a similar kinetic barrier controls both processes. The classical nucleation theory provides an accurate description of the observed nucleation rates if the crystal growth rate is used to describe the kinetic barrier for nucleation. The quantitative rates of both nucleation and growth for the competing polymorphs enable prediction of the overall rate of crystallization and its polymorphic outcome.


Assuntos
Vidro , Nifedipino , Cristalização , Vidro/química , Nifedipino/química , Temperatura , Temperatura de Transição
7.
Zhongguo Zhong Yao Za Zhi ; 47(14): 3923-3932, 2022 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-35850851

RESUMO

At present, many systematic reviews(SRs)/Meta-analysis of Aidi Injection combined with chemotherapy in the treatment of non-small cell lung cancer(NSCLC) have been published, and the effectiveness has been proved.However, the methodological quality and evidence quality of these SRs/Meta-analysis have not been evaluated, and their guiding role in the clinical practice needs to be further verified.In this study, SRs/Meta-analysis of Aidi Injection combined with chemotherapy in the treatment of NSCLC were assessed to provide evidence overview and basis for the application and decision-making of this drug in clinical practice.PubMed, Cochrane Library, EMbase, CNKI, VIP, Wanfang, and SinoMed databases were searched for research articles on SRs/Meta-analysis of Aidi Injection combined with chemotherapy in the treatment of NSCLC.The methodological quality and evidence quality of included 15 articles on SRs/Meta-analysis were evaluated by using the AMSTAR-2 and GRADE system.The results of SRs/Meta-analysis suggested that Aidi Injection combined with chemotherapy had certain advantages over chemotherapy alone in improving short-term efficacy, improving quality of life, and reducing leukopenia, thrombocytopenia, and the incidence of gastrointestinal adverse events.The results of the AMSTAR-2 checklist showed low quality for 11 SRs/Meta-analysis and extremely low quality for another four SRs/Meta-analysis.The top problems included failure to provide the preliminary protocol or guide, unreported funding sources, and non-assessed risk of bias in the included articles on the results.According to the results of the GRADE assessment, 32 of the 148 outcome indicators were of intermediate quality, 40 were of low quality, and 76 were of extremely low quality.The critical factor leading to the downgrade was the risk of bias, followed by imprecision and publication bias.Aidi Injection combined with chemotherapy in the treatment of NSCLC can enhance efficacy and reduce toxicity.However, due to the low methodological quality and evidence quality of the included research articles, the efficacy and safety of Aidi Injection combined with chemotherapy in the treatment of NSCLC still need to be further confirmed by high-quality studies.In the follow-up original research and SRs/Meta-analysis, the corresponding quality evaluation standards should be strictly followed to improve the quality of evidence.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Medicamentos de Ervas Chinesas , Neoplasias Pulmonares , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Metanálise como Assunto , Qualidade de Vida , Revisões Sistemáticas como Assunto
8.
J Med Virol ; 93(3): 1304-1313, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33002209

RESUMO

The outbreak of coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), has become a significant and urgent threat to global health. This review provided strong support for central nervous system (CNS) infection with SARS-CoV-2 and shed light on the neurological mechanism underlying the lethality of SARS-CoV-2 infection. Among the published data, only 1.28% COVID-19 patients who underwent cerebrospinal fluid (CSF) tests were positive for SARS-CoV-2 in CSF. However, this does not mean the absence of CNS infection in most COVID-19 patients because postmortem studies revealed that some patients with CNS infection showed negative results in CSF tests for SARS-CoV-2. Among 20 neuropathological studies reported so far, SARS-CoV-2 was detected in the brain of 58 cases in nine studies, and three studies have provided sufficient details on the CNS infection in COVID-19 patients. Almost all in vitro and in vivo experiments support the neuroinvasive potential of SARS-CoV-2. In infected animals, SARS-CoV-2 was found within neurons in different brain areas with a wide spectrum of neuropathology, consistent with the reported clinical symptoms in COVID-19 patients. Several lines of evidence indicate that SARS-CoV-2 used the hematopoietic route to enter the CNS. But more evidence supports the trans-neuronal hypothesis. SARS-CoV-2 has been found to invade the brain via the olfactory, gustatory, and trigeminal pathways, especially at the early stage of infection. Severe COVID-19 patients with neurological deficits are at a higher risk of mortality, and only the infected animals showing neurological symptoms became dead, suggesting that neurological involvement may be one cause of death.


Assuntos
Encéfalo/virologia , COVID-19/virologia , Viroses do Sistema Nervoso Central/virologia , Neurônios/virologia , SARS-CoV-2/patogenicidade , Animais , COVID-19/mortalidade , COVID-19/fisiopatologia , Viroses do Sistema Nervoso Central/mortalidade , Viroses do Sistema Nervoso Central/fisiopatologia , Líquido Cefalorraquidiano/virologia , Humanos , Vias Neurais , SARS-CoV-2/isolamento & purificação
9.
Mol Pharm ; 18(3): 1364-1372, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33522821

RESUMO

We report that the stability of amorphous clofazimine (CFZ) against crystallization is vastly improved by salt formation with a polymer without sacrificing dissolution rate. A simple slurry method was used to produce the amorphous salt of CFZ with poly(acrylic acid) (PAA) at 75 wt % drug loading. The synthesis was performed under a mild condition suitable for thermally unstable drugs and polymers. Salt formation was confirmed by visible spectroscopy and glass temperature elevation. The amorphous salt at 75 wt % drug loading is remarkably stable against crystallization at 40 °C and 75% RH for at least 180 days. In contrast, the amorphous solid dispersion containing the un-ionized CFZ dispersed in poly(vinylpyrrolidone) crystallized in 1 week under the same condition. The high stability of the amorphous drug-polymer salt is a result of the absence of a drug-polymer crystalline structure, reduced driving force for crystallizing the free base, and reduced molecular mobility. Despite the elevated stability, the amorphous drug-polymer salt showed fast dissolution and high solution concentration in two biorelevant media (SGF and FaSSIF). Additionally, the amorphous CFZ-PAA salt has improved tabletability and powder flow relative to crystalline CFZ. The CFZ-PAA example suggests a general method to prepare amorphous drugs with high physical stability under tropical conditions and fast dissolution.


Assuntos
Resinas Acrílicas/química , Clofazimina/química , Polímeros/química , Varredura Diferencial de Calorimetria/métodos , Química Farmacêutica/métodos , Cristalização/métodos , Composição de Medicamentos/métodos , Estabilidade de Medicamentos , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier/métodos
10.
Clin Oral Investig ; 25(11): 6321-6333, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33822289

RESUMO

OBJECTIVES: This study investigated the association of changes in cementum protein-1 (CEMP-1), dentine phosphoprotein (DPP), and c-terminal cross-linked telopeptide of type I collagen (CTX-I) levels in human gingival crevicular fluid (GCF) under constant load with external root resorption volume and amount of tooth movement. MATERIALS AND METHODS: In total, 11 healthy adult patients (mean age, 23.5 years [range, 18.3-37.7]; four men and seven women) were enrolled. GCF samples were obtained from premolars at T0, T1 (1 day), T2 (1 week), T3 (2 weeks), T4 (4 weeks), and T5 (8 weeks) under constant 100-gm buccal tipping force. Opposite premolars were used as controls. Teeth were extracted at T5, followed by quantification of external root resorption volume and histological analysis. RESULTS: In the test group, T5/T0 ratios of CEMP-1 and DPP levels, differential CEMP-1 levels between T5 and T0, and differential DPP levels between T2 and T0 correlated positively with root resorption volume (r = 0.734, 0.730, 0.627, and 0.612, respectively, all p < 0.05). CEMP-1 levels at T0 and T3 correlated negatively with root resorption volume (r = -0.603 and -0.706; all p < 0.05). CTX-I levels at T5 correlated positively with the amount of tooth movement (r = 0.848, p < 0.01). CONCLUSIONS: Alterations in CEMP-1 and DPP levels in human GCF at specific timepoints during orthodontic treatment may be associated with different degrees of external root resorption. CLINICAL RELEVANCE: This study demonstrates that changes in the levels of tissue-specific biomarkers in GCF may facilitate early detection of external root resorption during orthodontic tooth movement.


Assuntos
Reabsorção da Raiz , Adulto , Dente Pré-Molar , Biomarcadores/análise , Feminino , Líquido do Sulco Gengival/química , Humanos , Masculino , Técnicas de Movimentação Dentária , Adulto Jovem
11.
J Anesth ; 35(2): 270-287, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33515302

RESUMO

This review compares the effects of peripheral dexamethasone and dexmedetomidine on postoperative analgesia. We included six randomized controlled trials (354 patients) through a systematic literature search. We found that analgesia duration was comparable between dexamethasone and dexmedetomidine (58.59 min, 95% CI (confidence interval), - 66.13, 183.31 min) with extreme heterogeneity. Secondary outcome was also compared and no significant difference was observed in sensory block onset and duration and motor block duration and also for postoperative nausea and vomiting. It is noteworthy that dexamethasone reduced analgesic consumption (fentanyl) by 29.12 mcg compared with dexmedetomidine. We performed subgroup analyses and found no significant difference between the following: (1) lidocaine vs ropivacaine (P = 0.28), (2) nerve block vs nerve block + general anesthesia (P = 0.47), and (3) upper limb surgery vs thoracoscopic pneumonectomy (P = 0.27). We applied trial sequential analysis to assess the risks of type I and II errors and concluded that the meta-analysis was insufficiently powered to answer the clinical question, and further analysis is needed to establish which adjuvant is better. In conclusion, we believe that existing research indicates that dexamethasone and dexmedetomidine have equivalent analgesic effects in peripheral nerve blocks.


Assuntos
Adjuvantes Anestésicos , Dexmedetomidina , Anestésicos Locais , Dexametasona , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
12.
J Med Virol ; 92(11): 2269-2271, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32525575

RESUMO

As compared to many other viral pulmonary infections, there existed several peculiar manifestations in the COVID-19 patients, including the "silence" of pneumonia in both mild and severe cases and a long intensive care unit stay for those requiring invasive mechanical ventilation. Similar silent pneumonia has been documented in the infectioninduced by H5N1 influenza virus HK483 and was found to result from the direct attack of the virus on the bronchopulmonary C-fibers at the early stage and the final infection in the brainstem at the late stage. The long stay of critical patients in the intensive care unit is possibly due to the depression of central respiratory drive, which resulted in the failure to wean from the mechanic ventilation. Carotid and aortic bodies and bronchopulmonary C-fibers are two key peripheral components responsible for the chemosensitive responses in the respiratory system, while triggering respiratory reflexes depends predominantly on the putative chemosensitive neurons located in the pontomedullary nuclei. In view of the findings for the H5N1 influenza virus, the silence of pneumonia induced by SARS-CoV-2 may be due to the possible impairment of peripheral chemosensitive reflexes as well as the damage to the respiratory-related central neurons.


Assuntos
COVID-19/complicações , COVID-19/fisiopatologia , Rede Nervosa/patologia , Dispneia , Humanos , Virus da Influenza A Subtipo H5N1 , Influenza Humana , Unidades de Terapia Intensiva , Rede Nervosa/virologia , SARS-CoV-2/patogenicidade , Tórax/diagnóstico por imagem , Tomografia Computadorizada por Raios X
13.
New Phytol ; 222(2): 1012-1029, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30609067

RESUMO

Verticillium dahliae is a broad host-range pathogen that causes vascular wilts in plants. Interactions between three hosts and specific V. dahliae genotypes result in severe defoliation. The underlying mechanisms of defoliation are unresolved. Genome resequencing, gene deletion and complementation, gene expression analysis, sequence divergence, defoliating phenotype identification, virulence analysis, and quantification of V. dahliae secondary metabolites were performed. Population genomics previously revealed that G-LSR2 was horizontally transferred from the fungus Fusarium oxysporum f. sp. vasinfectum to V. dahliae and is exclusively found in the genomes of defoliating (D) strains. Deletion of seven genes within G-LSR2, designated as VdDf genes, produced the nondefoliation phenotype on cotton, olive, and okra but complementation of two genes restored the defoliation phenotype. Genes VdDf5 and VdDf6 associated with defoliation shared homology with polyketide synthases involved in secondary metabolism, whereas VdDf7 shared homology with proteins involved in the biosynthesis of N-lauroylethanolamine (N-acylethanolamine (NAE) 12:0), a compound that induces defoliation. NAE overbiosynthesis by D strains also appears to disrupt NAE metabolism in cotton by inducing overexpression of fatty acid amide hydrolase. The VdDfs modulate the synthesis and overproduction of secondary metabolites, such as NAE 12:0, that cause defoliation either by altering abscisic acid sensitivity, hormone disruption, or sensitivity to the pathogen.


Assuntos
Genômica , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Verticillium/genética , Verticillium/patogenicidade , Sequência de Bases , Etanolaminas/metabolismo , Genes Fúngicos , Variação Genética , Genoma Fúngico , Gossypium/genética , Ácidos Láuricos/metabolismo , Modelos Biológicos , Família Multigênica , Fenótipo , Metabolismo Secundário/genética
14.
Pharm Res ; 36(5): 67, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30877389

RESUMO

PURPOSE: To inhibit the surface crystallization and enhance the dissolution of the basic amorphous drug clofazimine by polymer nano-coating. METHODS: The free surface of amorphous clofazimine was coated by dip coating in an alginate solution at pH 7. The stability of the coated amorphous drug against crystallization was evaluated by X-ray diffraction and light microscopy. The effect of coating on dissolution rate was measured in simulated gastric fluid in an USP-II apparatus at 37°C. RESULTS: At pH 7, the weak base clofazimine (pKa = 8.5) is positively charged, while the weak alginic acid (pKa = 3.5) is negatively charged, allowing coating by electrostatic deposition. Coated amorphous particles remain nearly amorphous after one year under the accelerated testing condition 40°C/75% R.H. and show faster dissolution than uncoated particles. In the first hour of dissolution, coated amorphous particles dissolve 50% faster than uncoated amorphous particles, and a factor of 3 faster than crystalline particles of the same size. CONCLUSIONS: A pharmaceutically acceptable polymer, alginate, is coated on amorphous clofazimine by electrostatic deposition and effectively inhibits its surface crystallization and enhances its dissolution rate. This is the first time the nano-coating technique is applied to a basic drug using the principle of electrostatic deposition, demonstrating the generality of the approach.


Assuntos
Clofazimina/química , Nanopartículas/química , Polímeros/química , Alginatos/química , Química Farmacêutica , Cristalização , Estabilidade de Medicamentos , Concentração de Íons de Hidrogênio , Cinética , Tamanho da Partícula , Solubilidade , Eletricidade Estática , Propriedades de Superfície
15.
Mol Plant Microbe Interact ; 31(2): 260-273, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29068240

RESUMO

Cutinases have been implicated as important enzymes during the process of fungal infection of aerial plant organs. The function of cutinases in the disease cycle of fungal pathogens that invade plants through the roots has been less studied. Here, functional analysis of 13 cutinase (carbohydrate esterase family 5 domain-containing) genes (VdCUTs) in the highly virulent vascular wilt pathogen Verticillium dahliae Vd991 was performed. Significant sequence divergence in cutinase family members was observed in the genome of V. dahliae Vd991. Functional analyses demonstrated that only VdCUT11, as purified protein, induced cell death and triggered defense responses in Nicotiana benthamiana, cotton, and tomato plants. Virus-induced gene silencing showed that VdCUT11 induces plant defense responses in Nicotiana benthamania in a BAK1 and SOBIR-dependent manner. Furthermore, coinfiltration assays revealed that the carbohydrate-binding module family 1 protein (VdCBM1) suppressed VdCUT11-induced cell death and other defense responses in N. benthamiana. Targeted deletion of VdCUT11 in V. dahliae significantly compromised virulence on cotton plants. The cutinase VdCUT11 is an important secreted enzyme and virulence factor that elicits plant defense responses in the absence of VdCBM1.


Assuntos
Hidrolases de Éster Carboxílico/metabolismo , Gossypium/imunologia , Gossypium/microbiologia , Verticillium/enzimologia , Sequência de Aminoácidos , Regulação Fúngica da Expressão Gênica , Filogenia , Doenças das Plantas/microbiologia , Folhas de Planta/microbiologia , Nicotiana , Verticillium/metabolismo , Verticillium/patogenicidade , Virulência
16.
New Phytol ; 217(2): 756-770, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29084346

RESUMO

Verticillium dahliae isolates are most virulent on the host from which they were originally isolated. Mechanisms underlying these dominant host adaptations are currently unknown. We sequenced the genome of V. dahliae Vd991, which is highly virulent on its original host, cotton, and performed comparisons with the reference genomes of JR2 (from tomato) and VdLs.17 (from lettuce). Pathogenicity-related factor prediction, orthology and multigene family classification, transcriptome analyses, phylogenetic analyses, and pathogenicity experiments were performed. The Vd991 genome harbored several exclusive, lineage-specific (LS) genes within LS regions (LSRs). Deletion mutants of the seven genes within one LSR (G-LSR2) in Vd991 were less virulent only on cotton. Integration of G-LSR2 genes individually into JR2 and VdLs.17 resulted in significantly enhanced virulence on cotton but did not affect virulence on tomato or lettuce. Transcription levels of the seven LS genes in Vd991 were higher during the early stages of cotton infection, as compared with other hosts. Phylogenetic analyses suggested that G-LSR2 was acquired from Fusarium oxysporum f. sp. vasinfectum through horizontal gene transfer. Our results provide evidence that horizontal gene transfer from Fusarium to Vd991 contributed significantly to its adaptation to cotton and may represent a significant mechanism in the evolution of an asexual plant pathogen.


Assuntos
Fusarium/genética , Transferência Genética Horizontal , Genoma Fúngico , Genômica , Gossypium/microbiologia , Verticillium/genética , Verticillium/patogenicidade , Fatores de Virulência/metabolismo , Sequência de Bases , Evolução Molecular , Interações Hospedeiro-Patógeno/genética , Lactuca/microbiologia , Solanum lycopersicum/microbiologia , Família Multigênica , Filogenia , Especificidade da Espécie , Sintenia/genética , Virulência/genética
17.
Pharm Res ; 35(1): 23, 2018 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-29305725

RESUMO

PURPOSE: Inhibit the fast surface crystallization of amorphous drugs with gelatin nano-coatings. METHODS: The free surface of amorphous films of indomethacin or nifedipine was coated by a gelatin solution (type A or B) and dried. The coating's effect on surface crystallization was evaluated. Coating thickness was estimated from mass change after coating. RESULTS: For indomethacin (weak acid, pKa = 4.5), a gelatin coating of either type deposited at pH 5 and 10 inhibited its fast surface crystal growth. The coating thickness was 20 ± 10 nm. A gelatin coating deposited at pH 3, however, provided no protective effect. These results suggest that an effective gelatin coating does not require that the drug and the polymer have opposite charges. The ineffective pH 3 coating might reflect the poor wetting of indomethacin's neutral, hydrophobic surface by the coating solution. For nifedipine (weak base, pKa = 2.6), a gelatin coating of either type deposited at pH 5 inhibited its fast surface crystal growth. CONCLUSIONS: Gelatin nano-coatings can be conveniently applied to amorphous drugs from solution to inhibit fast surface crystallization. Unlike strong polyelectrolyte coatings, a protective gelatin coating does not require strict pairing of opposite charges. This could make gelatin coating a versatile, pharmaceutically acceptable coating for stabilizing amorphous drugs.


Assuntos
Excipientes/química , Gelatina/química , Indometacina/química , Nanoestruturas/química , Nifedipino/química , Química Farmacêutica/métodos , Cristalização , Humanos , Interações Hidrofóbicas e Hidrofílicas , Cinética , Microscopia/métodos , Tamanho da Partícula , Transição de Fase , Solubilidade , Propriedades de Superfície
18.
J Chem Phys ; 149(5): 054503, 2018 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-30089376

RESUMO

The rate of crystal nucleation has been measured in four glass-forming molecular liquids: D-sorbitol, D-arabitol, D-xylitol, and glycerol. These polyalcohols have similar rates of crystal growth when compared at the same temperature relative to Tg (the glass transition temperature), peaking near 1.4 Tg, while the nucleation rates J are vastly different. In D-sorbitol and D-arabitol, J reaches a maximum of ∼108 m-3 s-1 near 1.1 Tg, whereas J < 10-2 m-3 s-1 in D-xylitol and <1 m-3 s-1 in glycerol based on no nucleation in large samples after long waits. This confirms the fundamentally different mechanisms for nucleation and growth. Near Tg, both nucleation and growth slow down with a similar temperature dependence, suggesting a similar kinetic barrier for the two processes. This temperature dependence is significantly weaker than that of viscosity η, approximately following η-0.75. This indicates that viscosity is a poor representative of the kinetic barrier for nucleation, and a better choice is the crystal growth rate. Under the latter assumption, the classical nucleation theory (CNT) describes our data reasonably well, yielding σ = 0.013 J/m2 for D-sorbitol and 0.026 J/m2 for D-arabitol, where σ is the critical nucleus/liquid interfacial free energy. There is no strong indication that the CNT fails as the length scale for corporative rearrangement exceeds the size of the critical nucleus, as recently suggested for lithium disilicate.

19.
Zhongguo Zhong Yao Za Zhi ; 43(21): 4288-4294, 2018 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-30583631

RESUMO

A new composite organic oscillating reaction system based on BrO3-Ce(SO4)2-H2SO4-malonic acid/tartaric acid was proposed in this paper. On the basis of the influence of the concentration of each component on the stability and characteristic parameters of the blank system, the electrochemical fingerprints of 30 kinds of traditional Chinese medicines (TCM) were obtained. The results showed that the electrochemical fingerprint can be used for the identification of TCMs, the distinguishment of different parts and the appraisal of genuineness, which is fast, sensitive and accurate. At the same time, we explored and verified the mechanism of oscillation and the formation mechanism of TCM fingerprint.


Assuntos
Medicamentos de Ervas Chinesas/química , Técnicas Eletroquímicas , Malonatos/química , Tartaratos/química , Medicina Tradicional Chinesa , Compostos Fitoquímicos/análise
20.
Environ Microbiol ; 19(5): 1914-1932, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28205292

RESUMO

Glycoside hydrolase 12 (GH12) proteins act as virulence factors and pathogen-associated molecular patterns (PAMPs) in oomycetes. However, the pathogenic mechanisms of fungal GH12 proteins have not been characterized. In this study, we demonstrated that two of the six GH12 proteins produced by the fungus Verticillium dahliae Vd991, VdEG1 and VdEG3 acted as PAMPs to trigger cell death and PAMP-triggered immunity (PTI) independent of their enzymatic activity in Nicotiana benthamiana. A 63-amino-acid peptide of VdEG3 was sufficient for cell death-inducing activity, but this was not the case for the corresponding peptide of VdEG1. Further study indicated that VdEG1 and VdEG3 trigger PTI in different ways: BAK1 is required for VdEG1- and VdEG3-triggered immunity, while SOBIR1 is specifically required for VdEG1-triggered immunity in N. benthamiana. Unlike oomycetes, which employ RXLR effectors to suppress host immunity, a carbohydrate-binding module family 1 (CBM1) protein domain suppressed GH12 protein-induced cell death. Furthermore, during infection of N. benthamiana and cotton, VdEG1 and VdEG3 acted as PAMPs and virulence factors, respectively indicative of host-dependent molecular functions. These results suggest that VdEG1 and VdEG3 associate differently with BAK1 and SOBIR1 receptor-like kinases to trigger immunity in N. benthamiana, and together with CBM1-containing proteins manipulate plant immunity.


Assuntos
Glicosídeo Hidrolases/metabolismo , Gossypium/microbiologia , Nicotiana/microbiologia , Imunidade Vegetal/fisiologia , Receptores de Superfície Celular/metabolismo , Verticillium/patogenicidade , Morte Celular , Doenças das Plantas/microbiologia , Proteínas de Plantas/metabolismo , Verticillium/metabolismo , Fatores de Virulência/metabolismo
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