Analysis of drug resistance and pathogenicity of six strains of Klebsiella pneumoniae / 安徽医科大学学报

Objective @#To investigate the drug resistance and pathogenicity of six clinical isolates of Klebsiella pneu- moniae (Kp) ，and to provide a basis for prevention and treatment of Kp infection．@*Methods @#The six strains from different hospitals were isolated ，cultured ，and identified by species-specific gene khe． Their whole genome se- quences (WGS) were obtained using next-generation sequencing technology (NGS) ．Based on the WGS，the cap- sular serotypes，sequence types (ST) and drug-resistance genes of six strains were identified．The capsular sero- type genes and virulence genes were validated or identified using PCR. Broth microdilution tests were conducted to validate their drug susceptibility，and mice were challenged with Kp aerosols by MicroSprayer aerosolizer to evaluate their pathogenicity. @*Results @# The six strains were all serotype K2 but belonged to four ST types ( ST14 ，ST65， ST700，and ST86) ，and collectively carried six virulence genes and 23 drug-resistance genes．All the six strains were resistant to ampicillin，but only one strain was multidrug-resistant．Four strains exhibited high mucoid charac- teristics．Five strains could cause mortality in mice，which were preliminary identified as high virulence strains. @*Conclusion @# For the six Kp clinical isolates from different sources，only one strain named NY 13294 is both multi- drug-resistant and highly virulent，and other four highly virulent strains are resistant to one or two types of antibiot- ics.

Weight-dependent Fluorescence Lifetime Imaging for Viscosity Detection in Glycerol-water Mixtures / 生物化学与生物物理进展

ObjectiveBased on fluorescence lifetime imaging technology, a novel method for viscosity detection is proposed and the capability of different weighting of fluorescence lifetimes in distinguishing the viscosity of glycerol-water mixtures is evaluated, aiming to enhance the accuracy and reliability of viscosity differentiation. MethodsThis approach incorporates the principles of electronic weighting, introducing both amplitude-weighted average fluorescence lifetime (τm) and intensity-weighted average fluorescence lifetime (τi). Viscosity changes in glycerol-water mixtures are detected through τm and τi. τm Reflects the relationship between fluorescence signal amplitude and time, while τi focuses on the time-varying characteristics of fluorescence signal intensity. ResultsThe results of both τm and τi mutually corroborate each other, not only enhancing the reliability in detecting viscosity changes in glycerol-water mixtures but also revealing their unique roles in the detection process. Although τm plays a crucial role in capturing changes in fluorescence signal amplitude, τi exhibits higher accuracy in viscosity detection when considering the time-varying characteristics of fluorescence signal intensity. It is particularly noteworthy that, due to τi’s greater sensitivity, microenvironment viscosity detection can be directly analyzed using τi. This provides a more convenient approach for real-time, highly sensitive microfluidic viscosity monitoring. Therefore, through the comprehensive utilization of τm and τi, a more thorough and accurate understanding of the viscosity information in glycerol-water mixtures can be obtained, and specific parameters can be selected for in-depth analysis based on specific needs. ConclusionThe combination of amplitude weighting and intensity weighting allows for a more sensitive identification of subtle changes in viscosity under different conditions. The innovation of this method lies in its simultaneous consideration of multiple parameters, enhancing sensitivity and distinguishability to variations in viscosity. Therefore, this weighted-dependent fluorescence lifetime imaging technique not only introduces a novel approach for viscosity detection in glycerol-water mixtures but also provides a powerful analytical tool for various fields, including microfluidics, rheology, and research on novel functional materials.

Differences According to the Type of Exogenous Hyaluronic Acid and its Frequency of Infiltration in the Treatment of Temporomandibular Osteoarthritis / Diferencias Según el Tipo de Ácido Hiaurónico Exógeno y su Frecuencia de Infiltración en el Tratamiento de la Osteoartritis Temporomandibular

SUMMARY: One of the most important minimally invasive treatments today in temporomandibular joint osteoarthritis (TMJ- OA) is the intra-articular exogenous hyaluronic acid (HA) injection, which has yielded good results in pain relief and improves mandibular function with few side effects. However, the effectiveness of HA continues to be controversial, partly due to the heterogeneity in the injection protocols in their molecular weight, viscosity and frequency of infiltration, among other properties. The aim of this review is to identify the differences in the histological and clinical effects of the different types of HA and the frequency of infiltration on TMJ-OA treatment. Materials and methods: A bibliographic search was performed in the PubMed, Web of Science and Scopus databases. The search was limited up to September 2022. Search terms included "osteoarthritis", "hyaluronic acid, "molecular weight", "concentration", "viscosity", "dose" and "temporomandibular", using AND/OR as Boolean terms. Results: Exogenous HA in its different molecular weights offers an improvement in histological and clinical characteristics. Apparently, low and medium molecular weight HA presents better results. No clinical studies related to the degree of HA viscosity were found. Respect to the frequency of infiltration, single injection, weekly injections for 3 weeks, weekly injections for 5 weeks and other protocols are used. However, their comparison is complex. There seems to be differences in the effects of the different HA preparations for the treatment of TMJ-OA, mainly in their molecular weight. However, the evidence remains scant.

Uno de los tratamientos mínimamente invasivos más importantes en la actualidad en la artrosis de la articulación temporomandibular (OATM) es la inyección intraarticular de ácido hialurónico (AH) exógeno, que ha dado buenos resultados en el alivio del dolor y mejora la función mandibular con pocos efectos secundarios. Sin embargo, la efectividad del AH continúa siendo controversial, en parte debido a la heterogeneidad en los protocolos de inyección en cuanto a su peso molecular, viscosidad y frecuencia de infiltración, entre otras propiedades. El objetivo de esta revisión fue identificar las diferencias en los efectos histológicos y clínicos de los diferentes tipos de HA y la frecuencia de infiltración en el tratamiento de TMJ-OA. Se realizó una búsqueda bibliográfica en las bases de datos PubMed, Web of Science y Scopus. La búsqueda se limitó hasta septiembre de 2022. Los términos de búsqueda incluyeron "osteoartritis", "ácido hialurónico", "peso molecular", "concentración", "viscosidad", "dosis" y "temporomandibular", utilizando AND/OR como términos booleanos. El HA exógeno en sus diferentes pesos moleculares ofrece una mejora en las características histológicas y clínicas. Aparentemente, el AH de bajo y medio peso molecular presenta mejores resultados. No se encontraron estudios clínicos relacionados con el grado de viscosidad del HA. Respecto a la frecuencia de infiltración, se utilizan inyecciones únicas, inyecciones semanales durante 3 semanas, inyecciones semanales durante 5 semanas y otros protocolos. Sin embargo, su comparación es compleja. Parece haber diferencias en los efectos de las diferentes preparaciones de HA para el tratamiento de la OA-TMJ, principalmente en su peso molecular. Sin embargo, la evidencia sigue siendo escasa.

Structural and Rheological Properties of Exopolysaccharides Produced by Some Lactic Acid Bacterial Strains Isolated from Palm Wine

Aims: This study evaluated the physical, chemical and rheological properties of exopolysaccharides (EPSs) produced by Lactic Acid Bacteria (LAB) isolated from palm wine. Materials and Methods: EPSs from palm wine LAB strains were produced on 6% sucrose broth, purified and freeze-dried prior to analyses. Molecular weights (MW), rheological and structural composition (functional groups) of the EPSs were determined using standard methods and Fourier transform infrared spectroscopy (FTIR). Results: The average MW of the EPSs ranged from 2.02×106 to 6.53×106 Da while the flow index (n) values ranged from 0.03-3.13 at 0.2%, 0.06-1.51 at 0.4%, 0.38 - 1.85 at 0.6%, 0.14 - 2.26 at 0.8% and 0.55 - 6.42 at 1% concentrations at elevated temperatures for EPS solutions from the ten LAB species. The FTIR spectrum revealed prominent peaks of various groups of OH (3420 cm-1) and CH3 bending (2090 cm-1) in all the EPSs corresponding to both hydroxyl and amine groups, and aliphatic C-H bonds, respectively. EPS synthesized by Leuconostoc lactis, Lactococcus lactis subsp lactis and Lactiplantibacillus plantarum showed weak absorption peaks (1148 – 1145 cm-1) indicating the C-O-C and C-O bonds, while absorption peaks of Lactobacillus lactis, Lactobacillus acidophilus and Lactiplantibacillus plantarum (1267 – 1253 cm-1) indicated O- acetyl ester and other non-sugar components. Conclusions: The FTIR spectra, rheological properties and molecular weight of EPSs synthesized by the ten LAB strains indicated potentials that could be exploited in different industrial applications, and as stabilizers in food industries

Importancia de la medición de la Viscosidad sanguínea: retos y limitaciones

La sangre es una mezcla de componentes que tiene su propia identidad. Una de las propiedades físicas que adquiere es su viscosidad, la cual es la resistencia que ofrece para desplazarse. A diferencia de sus componentes (como glucosa, hemoglobina, colesterol, etc.), la sangre no posee un nivel único de viscosidad, sino que esta es variable debido a diversos factores. Exponemos algunos principios físicos que nos permitirán entender mejor esta dinámica de la viscosidad sanguínea, y su posible aplicación en algunos fenómenos hemodinámicos, así como la complejidad de su medición en la práctica clínica habitual.

Blood is a mixture of components that has its own identity. One of the physical properties that it acquires is its viscosity, which is the resistance it offers to move. Unlike its components (such as glucose, hemoglobin, cholesterol, etc.), blood does not have a single level of viscosity, but it is variable due to various factors. We present some physical principles that will allow us to better understand these dynamics of blood viscosity, and its possible application in some hemodynamic phenomena, as well as the complexity of its measurement in routine clinical practice.

Short-Term Changes of Graft Viscosity after Anterior Cruciate Ligament Reconstruction / 医用生物力学

Objective To study the short-term variation patterns of graft viscosity after anterior cruciate ligament reconstruction (ACLR) surgery. Methods Six male New Zealand rabbits were selected. The ACLR animal model of unilateral knee was made with Achilles tendon as the graft. The experimental rabbits were euthanized 15 days after ACLR surgery, with removal of the graft, healthy anterior cruciate ligament (ACL) and Achilles tendon. The cross-sectional area and viscosity coefficient of the graft were measured, and the creep experiments were carried out under equilibrium conditions of 0.1 MPa and 1 MPa, respectively. The viscosity coefficent was calculated. Variation patterns of graft viscosity were summarize. The grafts were compared with healthy ACL. Results The cross-sectional area of the graft increased slowly within 15 days after ACLR surgery. The viscosity of ACL and graft changed nonlinearly. The viscosity coefficient was quite different under different stresses. The viscosity coefficient of the graft decreased with the time after ACLR surgery, which was more obviously under the condition of low stress. Conclusions The results are helpful to guide the implementation of early postoperative rehabilitation plan after ACLR surgery .

Can different polymerization times affect the surface microhardness, water sorption, and water solubility of flowable composite resins?

This in vitro study evaluated and compared the effects of different polymerization times on the surface microhardness, water sorption, and water solubility of flowable composite resins. Three flowable composite resins [Es Flow (ESF), IGOS Flow (IGF), Estelite Flow Quick (EFQ)] were tested in this study. Each flowable composite resin (n = 7) was polymerized in a disc-shaped mould (1x10 mm) with an LED light-curing unit (D Light Pro) for two different times (20 and 40 sec.). The top surfaces of all specimens were polished (Sof-Lex). The surface microhardnesses of the flowable composite resins were measured with a Vickers HMV microhardness tester. Water sorption and water solubility were calculated according to the ISO 4049 standard. One-way ANOVA and post hoc Tamhane, Dunnett, and Tukey tests were used in the statistical analyses. Pearson's and Spearman's rho correlation tests were used to assess possible correlations between the different variables. The results were evaluated with a significance of p<0.05. In terms of microhardness, a significant difference was found between materials at the same polymerization times (p<0.05). All materials showed water sorption of less than 40 µg/mm3 and water solubility of less than 7.5 µg/mm3 by following ISO 4049. The correlations among surface microhardness, water sorption, and water solubility showed that the differences were determined by the materials and the polymerization times. The physical properties of all flowable composite resin materials were enhanced after polymerization for twice the time recommended by the manufacturers.

Possible Effects of Oriented Magnetic Fields on Human Blood Pressure

Abstract Background: There have been scattered reports indicating the possibility that applied magnetic fields can lower human blood viscosity, which has been considered as encouraging for decreasing blood pressure as a result of greater fluidity. Additional motivation comes from partial studies in animals showing some response of vascular variables to magnetic fields. Recently developed FeNbB magnets enable topical application to appropriate sites of much stronger permanent magnetic fields than previously available. Objectives: To establish whether powerful magnetic fields permanently applied along important arteries of the human body can lower blood pressure and, if so, to what extent. Methods: Ambulatory blood pressure tests were performed on 70 patients, half of them wearing real magnets, while the other 35 patients were wearing a similar placebo. Magnets or placebo devices were assigned at random. Each patient underwent two consecutive ambulatory 24-hour blood pressure (BP) tests; the first without a device and the second one with a device. Results: Results were compiled and analyzed only after the last measurement was completed. Individual responses, average values, standard deviations, information content, and Student's t test showed that no difference was found between measurements in either group. Conclusion: Permanent strong magnetic fields applied along the main arteries of the human body do not alter blood pressure. This was observed both in statistical terms and in individuals as well.

Simulation of density, viscosity and ultrasonic velocity data of 3-bromoanisole + methanol mixtures at different temperatures

SUMMARY Aim: To represent mathematically the reported physico-chemical properties (PCPs) of binary mixtures of 3-bromoanisol + methanol at various temperatures by using a single model with seven curve-fit parameters. Results: Besides the correlation models, the applicability of training the proposed model using a minimum number of experimental data and prediction of the rest of data points with acceptable prediction error is also shown.

Objetivo: representar matemáticamente las propiedades fisicoquímicas (PCP) de mezclas binarias de 3-bromoanisol + metanol a varias temperaturas, utilizando un modelo único con siete parámetros de ajuste de curva. Resultados: además de los modelos de correlación, también se muestra la aplicabilidad del entrenamiento del modelo propuesto utilizando un número mínimo de datos experimentales y la predicción del resto de puntos de datos con un error de predicción aceptable.

Objetivo: representar matematicamente as propriedades físico-químicas reportadas (PCPs) de misturas binárias de 3-bromoanisol + metanol em várias temperaturas usando um único modelo com sete parâmetros de ajuste de curva. Resultados: além dos modelos de correlação, a aplicabilidade do treinamento do modelo proposto usando um número mínimo de dados experimentais e previsão do restante dos pontos de dados com erro de previsão aceitável também é mostrada.

Flow Estimation Method of Centrifugal Left Ventricular Assist Device Based on Motor Parameters / 医用生物力学

Objective To study CH-VAD blood pump developed by CH Biomedical Inc., a method for estimating the real-time flow of blood pump was established by using the voltage, current, speed, duty cycle, and fluid viscosity as the input data. Methods The blood pump system was disassembled into two modules, the motor and the centrifugal pump. Firstly, the output torque of the motor was calculated according to the voltage, current, speed and duty cycle of the motor, then the relationship between flow and torque at different speeds and viscosities was tested through experiments, and a fitting model was established based on the experimental data. Results The fit goodness of Pump 1 and Pump 2 reached 0.982 6 and 0.982 9,respectively. The fitting parameters were used for verification. When the viscosity changed, the root mean square error for the estimated flow of Pump 1 and Pump 2 was 0.260 and 0.274 L/min, respectively. The fitting parameters and estimated results of the two blood pumps were in good agreement. The flow estimation method could follow the actual flow waveform in real time, and the accuracy of the estimated average flow was not affected by the pulsation. Conclusions The flow estimation method proposed in this paper is suitable for CH-VAD blood pumps. It can accurately estimate the flow of blood pumps in the range of speed 1 600-3 600 r/min, flow 0.4-8 L/min, viscosity 1.2-5 mPa·s, and can follow the flow waveform well under pulsating conditions.

A new preheating thermoviscous composite for restoration of non-carious cervical lesions: a 6-month randomized clinical trial / Um novo compósito termoviscoso de pré-aquecimento para restauração de lesões cervicais não cariosas: ensaio clínico randomizado de 6 meses

Objetivo: Este ensaio clínico randomizado, duplo-cego e boca dividida avaliou o desempenho clínico de um novo compósito termoviscoso com pré-aquecimento (PHT) em comparação com uma resina composta sem aquecimento (NHT) em restaurações de lesões cervicais não cariosas (LCNCs) durante um período de 6 meses. Material e Métodos: 120 restaurações foram realizadas em LCNCs com dois materiais restauradores (n = 60). Após a profilaxia, os dentes foram isolados com isolamento de fio retrator/rolos de algodão e um adesivo universal foi aplicado na estratégia de condicionamento seletivo do esmalte. Para o grupo PHT o aquecimento foi realizado a 68°C usando um aquecidor de bancada por 3 min. Por outro lado, para o grupo NHT, nenhum aquecimento foi aplicado. Ambos os materiais restauradores foram colocados no dispensador de cápsulas e inseridos nas LCNCs. Após 6 meses, o desempenho clínico das restaurações foi avaliado de acordo com os critérios FDI. A análise estatística foi realizada com teste Qui-quadrado para todos parâmetros da FDI (α = 0,05). Resultados: Apenas três restaurações no grupo NHT foram perdidas/fraturadas após seis meses de acompanhamento. As taxas de retenção (intervalo confiança 95%) por seis meses foram de 97,5% (88,6% - 99,0%) para o grupo NHT e 100% (93,9% - 100%) para o grupo PHT (p > 0,05). Vinte e duas restaurações (8 para NHT e 14 para PHT) apresentaram pequenos defeitos de adaptação marginal aos seis meses de acompanhamento (p > 0,05). Vinte e seis restaurações apresentaram alguma retenção de biofilme aos seis meses de acompanhamento (11 para NHT e 15 para PHT; p > 0,05). Em relação a todos os outros parâmetros de FDI avaliados, todas as restaurações foram consideradas clinicamente aceitáveis. Conclusão: O desempenho clínico do novo compósito termoviscoso de pré-aquecimento mostrou-se promissor após 6 meses de avaliação clínica quando aplicado em LCNCs.(AU)

Objective: This double-blind, split-mouth randomized clinical trial evaluate the clinical performance of a new preheating (PHT) thermoviscous composite compared to a non-heating (NHT) composite resin in restorations of non-carious cervical lesions (NCCLs) over a period of 6-month. Material and Methods: 120 restorations were performed on NCCLs with two restorative materials (n = 60). After prophylaxis, the teeth were isolated with retraction cord isolation/cotton rolls and one universal adhesive was applied in the selective enamel etching strategy. For the PHT group heating was carried out at 68°C using a heater bench for 3 min. On the other side, for the NHT group, no heating was applied. Both restorative materials were placed in the caps dispenser and inserted in the NCCLs. The restorations were evaluated after 6-month of clinical performance according to the FDI criteria. Statistical analysis was performed with Chi-square test for all FDI parameters (α = 0.05). Results: Three restorations only in the NHT group were lost/fractured after six months follow-up. The retention rates (confidential interval 95%) for six months were 97.5% (88.6% - 99.0%) for the NHT group and 100% (93.9% - 100%) for the PHT group (p > 0.05). Twenty-two restorations (8 for NHT and 14 for PHT) presented small marginal adaptation defects at the six-months follow-up (p > 0.05). Twenty-six restorations were found to have biofilm retention in the six-month recall (11 for NHT and 15 for PHT; p > 0.05). Regarding all others FDI parameters evaluated, all restorations were considered clinically acceptable. Conclusion: The clinical performance of the new preheating thermoviscous was found to be promise after 6-month of clinical evaluation when applied in NCCLs (AU)

Plastination with low viscosity silicone: strategy for less tissue shrinkage

Plastination is an anatomical technique for preserving biological tissues based on the principle of replacing body fluids with a curable polymer. An inconvenient aspect of this technique is the tissue shrinkage it causes; several studies seek ways to reduce or avoid this shrinkage. Additionally, there are no studies in the literature that quantitatively evaluate the use of low viscosity silicones in plastination having shrinkage of tissue as a parameter. Therefore, this study aimed to evaluate the use of Silicones S10 (Biodur) and P1 (Polisil) in the plastination of different types of biological tissues of a sliced human body, having as a parameter the tissue shrinkage caused in the forced impregnation stage. Human cardiac, pulmonary, splenic, renal, hepatic, muscular, and bone tissues were analyzed. For such purpose, a male human body was used, sliced in 13-15-mm-thick pieces, having as a parameter the before and the after plastination with the different silicones. The standard protocol of the plastination of the slices was followed: dehydration, forced impregnation, and curation. Half of the pieces obtained were plastinated with silicone P1 (group P1) and the other half with S10 (group S10). All tissues and anatomical segments analyzed in this study showed less or equal shrinkage when plastination of the control group (S10) was compared with that of the P1 group. Therefore, we concluded that the lower viscosity silicone promoted less tissue shrinkage, making it a viable alternative to the reference.

Alterations in haematological and clotting profile of post-menopausal women in Benin City, Nigeria

Background: The cessation of ovarian functions at menopause and the accompanying decline in the production of ovarian steroid hormones creates a unique set of health concerns for women. Reductions in sex steroid levels, particularly oestrogen, have been associated with various diseases and conditions, including bleeding disorders, coronary heart disease (CHD), osteoporosis, cognitive dysfunction, urinary incontinence, hot flushes, and mood changes, among others. Objective: To determine changes in haemorheological and clotting profile in post-menopausal women. Methods: Two hundred participants comprising one hundred and fifty post-menopausal women and fifty healthy pre-menopausal control subjects were studied. The investigations carried out include whole blood viscosity, plasma viscosity, fibrinogen concentration, Prothrombin time (PT), Activated partial thromboplastin time with kaolin (APTTK) levels and complete blood count using standard methods. Results: The mean age (p=0.01), platelet count (p= 0.013), neutrophil (p= 0.03), neutrophil to lymphocyte ratio (p= 0.045) and platelet to lymphocyte ratio (p=0.044) in postmenopausal women were significantly higher while lymphocyte count (p= 0.004) was significantly lower in postmenopausal compared to premenopausal women. Similarly, plasma oestradiol (p= 0.001), plasma viscosity (p= 0.03), relative blood viscosity (p= 0.03), whole blood viscosity (p= 0.03) and PTTK(p= 0.04) were significantly lower among postmenopausal women compared to premenopausal control subjects. Conclusion: Relative plasma viscosity correlated positively with age. There were significantly lower levels of haemorheological and clotting profile in post-menopausal women. These changes may be due to age or a decline in circulating oestrogen levels.

Effect of process variables on the physicochemical and rheological properties of yogurt / Efecto de las variables de proceso sobre las propiedades fisicoquímicas y reológicas de yogur

ABSTRACT In this research, the effect of the lactic starter culture, the fermentation time, the incubation temperature and the percentage of fat on the firmness and consistency of a fermented milk drink was evaluated through physicochemical characteristics of total acidity, pH, syneresis and flow behavior. The purpose was to find the best formulation that extends the shelf life of yogurt, leading to an improvement in the manufacturing process of a local dairy company in Barrancabermeja (Santander, Colombia). Quality criteria were evaluated by means of the percentage of acidity and pH of the yogurt, as well as its syneresis and rheological parameters during a storage time of 24 hours and 7 days in refrigeration. Acceptable quality parameters were obtained for the yogurt prepared with an inoculum concentration of 2%, an incubation temperature of 40°C and an incubation time of 150 minutes. In addition, better properties of firmness and consistency were found, with absence of syneresis and viscosity in the accepted range, for this dairy product.

RESUMEN En esta investigación, se evaluó el efecto del cultivo iniciador láctico, el tiempo de fermentación, la temperatura de incubación y el porcentaje de grasa en la firmeza y consistencia de una bebida de leche fermentada, a través de las características fisicoquímicas de acidez total, pH, sinéresis y comportamiento de flujo. El propósito fue encontrar la mejor formulación que extienda la vida útil del yogur, lo que lleva a un perfeccionamiento del proceso de fabricación de una empresa local de productos lácteos en Barrancabermeja (Santander, Colombia). Se evaluaron criterios de calidad por medio del porcentaje de acidez y pH del yogurt, así como su sinéresis y parámetros reológicos, durante un tiempo de almacenamiento de 24 horas y de 7 días en refrigeración. Se obtuvieron parámetros de calidad aceptables para el yogurt, preparado con una concentración del inóculo de 2%, una temperatura de incubación de 40°C y un tiempo de incubación de 150 minutos. Además, se encontraron mejores propiedades de firmeza y de consistencia, con ausencia de sinéresis y viscosidad en el rango aceptado, para este producto lácteo.

Low- and high-viscosity bulk-fill resin composites / Resinas compostas bulk-fill de baixa e alta viscosidade

ABSTRACT The aim of this study was to compare low- and high-viscosity bulk-fill composites for Knoop microhardness (KHN), microtensile bond strength (MTBS) to dentin in occlusal cavities, and fracture strength (FS) in molars with mesialocclusal- distal restoration. Disk-shaped samples with different thicknesses (2 or 4 mm) of low-viscosity (SDR Flow, Dentsply) and high-viscosity bulk-fill composites (Filtek BulkFill, 3M ESPE; and Tetric-N Ceram Bulk Fill, Ivoclar Vivadent) were prepared for top and bottom KHN analysis (n=10). MTBS to dentin and fracture pattern was evaluated in human molars with occlusal cavities restored with (n=10): conventional nanocomposite (Z350XT, 3M ESPE), low-viscosity (Filtek Bulk-fill Flow, 3M ESPE) or high-viscosity bulk-fill composites (Filtek BulkFill). The FS and fracture pattern of human molar with mesial-occlusal-distal restorations submitted or not to thermomechanical cycling were investigated (n=10) using: intact tooth (control), and restoration based on conventional microhybrid composite (Z250, 3M ESPE), low-viscosity (SDR Flow) or high-viscosity bulk-fill composites (Filtek BulkFill). The data were submitted to split-plot ANOVA (KHN), one-way ANOVA (MTBS), two-way ANOVA (FS) followed by Tukey's test (α=0.05). For KHN, there was no significant difference for the resin composites between the top and bottom. For MTBS, no significant differences among the materials were detected; however, the low-viscosity composite presented lower frequency of adhesive failures. For FS, there was no significant difference between composites and intact tooth regardless of thermomechanical cycling. Low- and high-viscosity bulk-fill composites have comparable microhardness and microtensile bond strength when used in occlusal restorations. Likewise, the bulk-fill composites present similar fracture strength in molars with mesio-occlusal-distal restorations.

RESUMO O objetivo deste estudo foi comparar resinas compostas bulk- -fill de baixa e alta viscosidade quanto à microdureza Knoop (KHN), resistência de união a microtração (MTBS) em cavidades oclusais e carga à fratura (FS) em molares com restauração mesio-oclusal-distal. Amostras em forma de disco com diferentes espessuras (2 ou 4 mm) de resinas bulk-fill de baixa viscosidade (SDR Flow, Dentsply) e alta viscosidade (Filtek BulkFill, 3M ESPE; e Tetric-N Ceram Bulk Fill, Ivoclar Vivadent) foram obtidas para análise de KHN no topo e na base (n = 10). A MTBS em dentina e o padrão de fratura foram avaliados em molares humanos com cavidades oclusais restauradas com (n = 10): resina composta nanoparticulada convencional (Z350XT, 3M ESPE), resinas bulk-fill de baixa viscosidade (Filtek Bulk-fill Flow, 3M ESPE) ou alta viscosidade (Filtek BulkFill). Foram investigados a FS e o padrão de fratura de molares humanos em restaurações mesial-ocluso-distais sub metidas ou não à ciclagem termomecânica (n = 10), sendo: dente íntegro (controle), e restaurações baseadas em resina composta microhíbrida convencional (Z250, 3M ESPE); resinas bulk-fill de baixa viscosidade (SDR Flow) ou alta viscosidade (Filtek BulkFill). Os dados foram submetidos a split-plot ANOVA (KHN), one-way ANOVA (MTBS), two-way ANOVA (FS) seguidos do teste de Tukey (α = 0,05). Para KHN, não houve diferença significativa entre o topo e a base para as resinas compostas. Para MTBS, não foram detectadas diferenças significativas entre os materiais; entretanto, a resina bulk-fill de baixa viscosidade apresentou menor frequência de falhas adesivas. Para FS, não houve diferença significativa entre os materiais e o dente íntegro, independentemente da ciclagem termomecânica. As resinas bulk-fill de baixa e alta viscosidade têm microdureza e resistência à microtração comparáveis quando usados em restaurações oclusais. Da mesma forma, as resinas bulk-fill apresentam resistência à fratura semelhante em molares com restaurações mesio-oclusal-distais.

Efecto gelificante del agar de Gracilaria debilis en la elaboración de una compota de níspero (Manilkara zapota)

RESUMEN El agar se emplea en la industria alimenticia por su característica de estabilización y gelificación y el níspero es una fruta de sabor agradable, de fácil consumo y además tiene excelentes propiedades nutricionales. En este estudio se evaluó el efecto gelificante del agar extraído de Gracilaria debilis en la elaboración de una compota de níspero (Manilkara zapota). A las algas recolectadas se les extrajo agar mediante tratamiento alcalino con NaOH 0,04 M. Para la obtención de la compota se elaboraron tres fórmulas base, seleccionándose la que contenía 0,05% de ácido cítrico, 56,4% de agua, 6,0% de azúcar y 37,6% de puré de níspero; sirviendo de base para tres muestras (M1, M2, y M3) al 0,4%; 0,6% y 0,8% p/p de agar, respectivamente. El análisis sensorial indicó que la compota M2 fue la más aceptable, con valores de cenizas= 0,85±0,08%; cloruros= 0,085±0,014%; 18,0±0,4; y °Brix grasa= 0,50±0,01 g/100g; humedad= 64,0±3,0%; pH= 4,32±0,03; proteínas= 0,42±0,01 g/100g y sólidos totales= 35,9±3,0%. La viscosidad (-554±10 g·s) estuvo cercana al valor de una compota comercial (-430±4 g·s). M2 demostró estabilidad durante un mes ante aerobios mesófilos, con valores menores de 10 UFC/mL. Las concentraciones de agar influyeron únicamente en la viscosidad, ajustándose a una ecuación lineal con R²= 0,986. En alimentos que requieren en su preparación ser sometidos a altas temperaturas, como es el caso de las compotas, el agar presenta propiedades y comportamiento adecuado como gelificante.

ABSTRACT Agar is a used in the food industry for its stabilization and gelation characteristics and the medlar is a fruit with a pleasant taste, easy to consume where it provides excellent nutritional properties. In this study the effect of gelling extracted Gracilaria debilis agar was evaluated in the formulating a sapodilla (Manilkara zapota) compote. Agar was extracted from the collected algae by alkaline treatment with 0.04 M NaOH. To obtain compote, three base formulas were prepared, selected which containing 0.05% citric acid, 56.4% water, 6.0% sugar and 37.6% sapodilla puree; providing the basis for three samples (M1, M2 and M3) at the following concentrations: 0.4%; 0.6% and 0.8% w/w of agar, respectively. Sensory analysis indicated that the compote M2 had the most acceptable values, with ash content= 0.85±0.08%; chloride= 0.085±0.014%; 18.0±0,4 °Brix; fat= 0.50±0.01 g/100 g; humidity= 64.0±3.0%; pH= 4.32±0.03; protein= 0,42±0.01 g/100 g and total solids= 35.9±3.0%. The viscosity (-554±10 g·s) was close to the value of a commercial compote (-430±4 g·s). M2 showed stability for one month, against the aerobic mesophilic bacteria, with values less than 10 CFU/mL. It was observed that agar concentrations had influenced only in the viscosity by adjusting to a linear equation with R2= 0.986. In foods that require high temperatures in their preparation, such as compotes, agar has properties as well as the adequate behavior as a gelling agent.

Efficacy of Naoxintong capsule combined with butylphthalide injection on acute cerebral infarction and its effects on inflammatory factors, oxidative stress response and hemorheology / 中国基层医药

Objective:To investigate the effect of Naoxintong capsule combined with butylphthalide injection on inflammatory factors, oxidative stress response and hemorheology in patients with acute cerebral infarction. Methods:Eighty-six patients with acute cerebral infarction who received treatment in Zhuji Hospital of Traditional Chinese Medicine from December 2017 to December 2019 were included in this study. Thrombolysis and thrombectomy were contraindicated in these patients. They were randomly assigned to receive treatment either with butylphthalide injection (control group, n = 43) or butylphthalide injection and Naoxintong capsule (observation group, n = 43) for 2 weeks. Therapeutic effects, Barthel Index, inflammatory factors (C-reactive protein, intercellular adhesion molecule-1 and interleukin-6), oxidative stress response (malondialdehyde and superoxide dismutase) and hemorheology (whole blood viscosity at high and low shear rates, plasma viscosity and fibrinogen) were compared between the two groups. Results:Total effective rate in the observation group was significantly higher than that in the control group (93.02% vs. 72.09%, χ2 = 6.541, P < 0.05). After treatment, Barthel Index in the observation group was significantly higher than that in the control group [(61.51 ± 5.24) points vs. (50.43 ± 4.81) points, t = 10.215, P < 0.05). After treatment, serum levels of C-reactive protein, intercellular adhesion molecule-1, and interleukin-6 in the observation group were (4.42 ± 1.03) mg/L, (84.23 ± 5.05) μg/L and (94.33 ± 10.22) μg/L, respectively, which were significantly lower than those in the control group [(8.32 ± 1.71) mg/L, (103.51 ± 6.35) μg/L, (118.92 ± 13.31) μg/L, t = 12.810, 15.583, 9.609, all P < 0.05]. After treatment, serum malondialdehyde level in the observation group was significantly lower than that in the control group [(3.76 ± 0.78) μmol/L vs. (4.94 ± 0.90) μmol/L, t = 6.497, P < 0.05]. Serum superoxide dismutase level in the observation group was significantly higher than that in the control group [(35.76 ± 2.65) U/L vs. (30.34 ± 2.11) U/L, t = 10.492, P < 0.05]. After treatment, whole blood viscosity at high and low shear rates, plasma viscosity and fibrinogen levels in the observation group were (4.10 ± 0.51) mPa · s, (9.31 ± 1.36) mPa · s, (1.24 ± 0.26) mPa · s and (2.71 ± 0.40) g/L respectively, which were significantly lower than those in the control group [(5.72 ± 0.76) mPa · s, (11.49 ± 1.59) mPa · s, (2.21 ± 0.32) mPa · s and (3.92 ± 0.54) g/L, t = 11.607, 6.832, 15.427 11.807, all P < 0.05). Conclusion:Naoxintong capsule combined with butylphthalide injection is highly effective in the treatment of acute cerebral infarction. It can reduce inflammatory reaction and improve oxidative stress response and hemorheological changes.

The enlightenment of hemodynamic principleson for prevention and treatment of allograft rejection / 中华器官移植杂志

Antibody mediated rejection (AMR) starts from the binding of donor specific antibody (DSA) to its target antigen on endothelium. Whether or not a circulating DSA would bind to its static target depends on the relative strength between the antigen-antibody attraction potential energy and the kinetic energy of a circulating DSA. The attraction potential energy between antigen & antibody mainly depends on affinity of antibody to its target and is relatively constant. The kinetic energy of antibody depends on its velocity. The faster it moves the higher kinetic energy it possesses (E=mV 2/2). Therefore, the primary endothelial injury has always occurred in capillary which has the lowest blood flow rate. Even though DSA moves at the lowest velocity in capillary (≤1 mm/s), compared to its size (diameter<10 nm), the relative velocity of DSA is very high, which moves a distance of 100, 000 diameter of antibody per second. It is nearly 20, 000 times over the highest relative velocity of Bolt, the world record holder in 100 meters. Therefore, it is not easy for a fast-moving DSA to bind to its static target since the attraction potential energy between antigen and antibody needs to overcome the great kinetic energy of DSA. These basic concepts of hemodynamics and the relative velocity of DSA gives us at least the following inspirations: (1)It is easier for a DSA to bind its antigen in vitro, since there is no relative motion between antigen and antibody in test tube; while it is more difficult for a fast-moving DSA to bind to its static antigen in vivo, since the attraction potential energy between antigen & antibody needs to overcome the great kinetic energy of a fast-moving DSA.(2)A cytotoxic agent usually kills its peripheral blood target with a much higher depletion efficacy than for its target in tissue, since it runs with its circulating target without relative motion, while it is more difficult for a fast-moving agent with a great kinetic energy to bind its static target in tissue.(3)Some patients remain positive for DSA for a long time without the evidence of AMR. This is possibly due to a lower attraction potential energy between antigen-antibody, or due to a higher kinetic energy of a fast-moving DSA in the circumstance without microvascular occlusion.(4)Endothelial injury, resulting from ischemia and reperfusion or others, usually cause microvascular thrombosis, which results in partial or complete occlusion of microvascular system and favors antigen-antibody interaction.(5)Based on the fact that blood flow rate can affect antibody-antigen binding, we can reasonably infer that maintaining a good microcirculation in allograft will help to prevent or treat AMR. The strategies may include prevention of leukocyte adhesion, platelet deposition, red blood cell aggregation, and reduction of blood lipid and viscosity, to have plenty of water, and to do regular exercise. These strategies are equally important for prevention or treatment of cell mediated rejection.

Research on feedforward control method of mixing process for compound Danshen Dripping Pills based on quality by design(QbD) / 中国中药杂志

The mixing process is one of the key operation units for solid preparation of traditional Chinese medicine. The physical properties such as particle size, density and viscosity of the mixture are key factors that need to be controlled, which will directly affect the performance of the preparation molding process and product quality. Subsequent dripping process performance and appearance qua-lity of dripping pills will be affected by dynamic viscosity of materials in the mixing process. Based on this, with mixing process of compound Danshen dripping pills as the object, a feedforward control method for the dripping pill mixing process was established based on the concept of quality by design(QbD). Firstly, critical quality attribute(CQA)-dynamic viscosity, critical material attributes(CMAs)-the moisture content of compound Danshen extract, average molecular weight of polyethylene glycol 6000 and critical process parameter(CPP)-mixing temperature were identified through the analysis of properties for multiple batches of the raw materials and excipients as well as technological mechanism. Then the Box-Behnken experimental design was used to establish the regression model among CMA, CPP and CMA(R■=0.972 0, RMSE =16.24) to obtain the design space. Finally, through the verification of three batches within the design space, the mixing process temperature was adjusted according to the properties of the raw materials and exci-pients to achieve accurate control of the dynamic viscosity attribute. The relative deviation between the actual dynamic viscosity value and the target value was less than 3.0 %. The feedforward control of the mixing process of compound Danshen dripping pills was rea-lized in this study, which can contribute to improving quality consistency of the mixing process intermediates, simultaneously provide a reference for the research on the process quality control of other Chinese medicine dripping pills.