Green Nanotechnology: Harnessing Rice Husk Ash for Nano-Silica and Characterization Insights

In the form of nanoparticles, silica is a significant inorganic component of rice husk. Consequently, it is feasible to extract high purity amorphous silica nanoparticles by straightforward thermo-chemical processes. So, in this study, an eco-friendly chemical treatment method (Green Synthesis) was used to try and manufacture amorphous silica nanoparticles from rice husk ash. I had done synthesizing silica nanoparticle in Dept. of Soil Science and Agricultural chemistry, TNAU, Coimbatore in the year 2023 and the aim of this study is to characterize the silica nano particle and use it on agricultural crops. Selected region from X-ray diffraction analysis and Transmission Electron Microscopy, silica sample exhibited amorphous behaviour as seen in the electron diffraction patterns, whereas the Fourier-transform infrared Spectroscopy spectra primarily contained siloxane and silanol groups. Images obtained in Scanning Electron Microscopy (SEM) revealed the existence of primary nanoparticles with secondary microparticles, possibly as a result of their agglomeration. These silica nanoparticles can therefore be used in the fields of microelectronics, sensors, nano-additives and will be suitable on implication on agricultural crops.

Biofabrication and optimization of silver nanoparticles using Campsis sp. to explore their antimicrobial properties

Plant mediated green synthesis of silver nanoparticles (AgNPs) holds promising applications in the field of Biomedicine, Food packaging and Wound healing. In the present investigation, biofabrication of AgNPs was performed using the aqueous extracts of Campsis sp. (Family Bignoniaceae) leaves and flowers growing in the premises of Kirori Mal College, University of Delhi, Delhi. Optimization of AgNPs was performed to analyse the varying effect of pH (6.0, 8.0, 10.0) and silver salt concentration (2mM, 4Mm and 6Mm) in controlling the shape and size of AgNPs which in turn governs their further applications. Interestingly, change in colour of the reaction mixture from pale yellow to reddish brown indicated the formation of AgNPs. These AgNPs were further characterized by UV-Visible spectroscopy and showed peak in the range of 400-450 nm which confirmed the synthesis of silver nanoparticles. Dynamic light scattering and zeta potential analysis (DLS-Zeta) confirmed the size of AgNPs around 200-300 nm. A significant zone of inhibition was observed for both Staphylococcus aureus (gram-positive) and Escherichia coli (gram-negative) bacterial strains which revealed the antimicrobial potential of Campsis sp. AgNPs. Therefore, Campsis AgNPs may provide a green, eco-sustainable alternate method for sustainable production of nanomaterials for biomedical applications. These AgNPs may also show tremendous applications in food packaging, wound healing and biomedical fields.

Advancing male age differentially alters levels and localization patterns of PLCzeta in sperm and testes from different mouse strains / 亚洲男科学杂志(英文版)

Sperm-specific phospholipase C zeta (PLCζ) initiates intracellular calcium (Ca

Physico-chemical characterization of traditionally prepared Yashada bhasma

Background: Yashada bhasma has been found to be very useful for the treatment of ailments like diabetes, eye disorder, urinary disorder etc. Since bhasma is a metallic preparation, so to prove its nontoxicity; modern standardization of the prepared samples is a must apart from other organoleptictests as mentioned in the ancient text.Objectives: The present study is aimed to synthesize bio-compatible Yashada bhasma from bioincompatible zinc metal. Further, comparative study of their chemical and physical properties throughsome quality control tests, physico-chemical tests and modern tests like XRD, DLS, Zeta potential, SEMand EDAX are carried out.Materials and methods: Yashada bhasma is prepared by a three step process i.e. Shodhan, Jarana andMarana. The inclusion of plant extracts and herbs during calcination process enhances its medicinalqualities, and reduces it to a nano size.Results: The XRD analysis of Yashada bhasma shows hexagonal ZnO crystalline phase whereas the rawmetal confirms the presence of crystallite Zinc metal. DLS shows reduction in particle size of YashadaBhasma (339.8 nm) as compared to raw metal (2063 nm) and this reduction is further supported by SEMwhich shows the particle size of Yashada bhasma (324 nm) and raw metal (1-2m). The zeta potential valueconfirms the stability of Yashada bhasma. EDAX revealed difference in concentration of Zinc and Oxygenin both the samples.Conclusion: An effort has been made to characterize the preparation of Yashada bhasma using sophisticated analytical tools as a step towards standardization of the bhasma. The results help in scientificallyestablishing the findings in line with the principle of Ayurveda.

PEG-PCL Nanocapsules Containing Curcumin: Validation of HPLC Method for Analyzing Drug-loading Efficiency, Stability Testing and Cytotoxicity on NIH-3T3 Cell Line

Abstract Curcumin (CUR) shows potential use for treating cancer. However, CUR has low solubility and reduced bioavailability, which limit its clinical effect. Therefore, the development of nanocarriers can overcome these problems and can ensure the desired pharmacological effect. In addition, it is mandatory to prove the quality, the efficacy, and the safety for a novel nanomedicine to be approved. In that sense, this paper aimed (a) to prepare CUR-loaded polyethylene glycol-poly(ε-caprolactone) nanocapsules; (b) to validate an analytical method by high performance liquid chromatography (HPLC) for quantifying CUR in these nanoformulations; (c) to evaluate the physicochemical stability of these formulations; and to investigate their cytotoxicity on NIH-3T3 mouse fibroblast cells. The HPLC method was specific to CUR in the loaded nanocapsules, linear (r = 0.9994) in a range of 10.0 to 90.0 µg.mL-1 with limits of detection and quantification of 0.160 and 0.480 µg.mL-1, respectively. Precision was demonstrated by a relative standard deviation lower than 5%. Suitable accuracy (102.37 ± 0.92%) was obtained. Values of pH, particle size, polydispersity index, and zeta potential presented no statistical difference (p > 0.05) for CUR-loaded nanoparticles. No cytotoxicity was observed against NIH-3T3 mouse embryo fibroblast cell line using both the tetrazolium salt and sulforhodamine B assays. In conclusion, a simple and inexpensive HPLC method was validated for the CUR quantification in the suspensions of nanocapsules. The obtained polymeric nanocapsules containing CUR showed suitable results for all the performed assays and can be further investigated as a feasible novel approach for cancer treatment.

Activación de la célula T, alteraciones en el lupus eritematoso sistémico, una revisión narrativa / T-cell activation, alterations in systemic lupus erythematosus: A narrative review

Resumen La activación de los linfocitos T se inicia a través de la presentación de antígenos endógenos o exógenos por células presentadoras de antígenos a través del complejo mayor de histocompatibilidad, el cual se une a un receptor especializado presente en los linfocitos T. Este reconocimiento desencadena una cascada de señalización intracelular que conlleva a un aumento en la expresión de integrinas, modificaciones del citoesqueleto y producción de factores de transcripción involucrados en la liberación de citocinas y mediadores inflamatorios. Uno de los inductores más importantes en la activación celular es el complejo enzimático con acción tirosina cinasa. Las cinasas que pertenecen a la familia SRC (SFK), FYN y LCK están involucradas en un gran número de procesos importantes en la activación, modulación de la respuesta linfocitaria y el desarrollo de enfermedades autoinmunes. La regulación de la señalización de las cinasas, así como de proteínas adaptadoras involucradas en la activación del linfocito T, son fundamentales para mantener el umbral de activación y modulación de la respuesta del linfocito. La fosforilación de sitios de regulación positiva de estas proteínas es importante para permitir una configuración activa de la proteína y de esta forma su máxima capacidad como cinasa. La fosforilación de los sitios de regulación negativa conlleva a una configuración cerrada de la proteína de tal forma que reduce su función de cinasa e inhibe su función. Las alteraciones en la señalización por modificación de algunas proteínas citoplasmáticas se asocian en algunos casos al desarrollo de enfermedades autoinmunes, como el lupus eritematoso sistémico. En condiciones fisiológicas, el complejo receptor de linfocitos T se reagrupa con complejos proteicos que interactúan armónicamente para generar una sen al interna. Los eventos de señalización alterados son en parte los responsables de una expresión anómala de citocinas, entre ellas la interleucina-6 (IL-6), IL-10, IL-2, IFN y CD40 ligando; estas modificaciones alteran la capacidad de los linfocitos T para sobre estimular a los linfocitos B, traduciéndose en un aumento en la producción de autoanticuerpos y en el desencadenamiento de la enfermedad autoinmune.

Abstract The activation of T cells is initiated by the presentation of exogenous or endogenous antigens, by antigen presenting cells through the major histocompatibility complex, which binds to a special receptor on T cells. This acknowledgement triggers a cascade of intracellular signalling that leads to an increase in integrin expression, cytoskeletal modifications, and transcription factors production involved in the liberation of cytokines and inflammatory mediators. One of the most important inducers in cell activation is the enzymatic complex with tyrosine kinase action. The kinases which belong to the SRC (SFK) LCK and FYN family have been involved in a large number of important processes in the activation and modulation of the T cells response, as well as in the development of autoimmune diseases. Regulating the kinases signalling, as well as the adapter proteins involved in T cell activation, is essential for maintaining an activation threshold, as well as the modulation of cell response. The phosphorylation of the positive regulation sites of these proteins is important to allow an active configuration of the protein and thereby its maximum capacity as kinase. The phosphorylation of negative regulation sites leads to a closed configuration of the protein that reduces its kinase function, and thereby inhibits its own function. The alteration in signalling by the modification of certain cytoplasmic proteins in some cases is associated with the development of autoimmune diseases, such as systemic lupus erythematosus. Under physiological conditions the T cell receptor complex regroups with protein complexes that interact harmonically to generate an internal signal. The altered signalling events are partly responsible for an anomalous expression of cytokines, including the interleukin-6 (IL-6), IL-10, IL-2, IFN, and CD40 linking, these modifications affects the cells ability to over-stimulate T and B cells, resulting in an increased production of autoantibodies and the triggering of the autoimmune disease.

Prescription design of raloxifene nanoemulsion / 中国药学杂志

OBJECTIVE:To study formulation design of raloxifene nanoemulsion. METHODS: The solubilities of raloxifene in excipients of nanoemulsion were investigated. On the basis, emulsifier and oil were selected by the emulsifying ability. The combination and optimum proportion among co-emulsifier, oil and emulsifier were determined by the pseudo-ternary phase diagram. The effect of raloxifene on nanoemulsion prescription was studied by drug loading. Finally chitosan and carboxylated chitosan were used to regulate the Zeta potential of raloxifene nanoemulsions. RESULTS: The optimum formulation ratio of LOA, IPP, RH40 and ethanol for loading 15 mg raloxifene is 0.167 g∶0.333 g∶0.3 g∶0.2 g, respectively. The Zeta potentials of the nanoemulsions can be changed by chitosan and carboxylated chitosan from -0.954 mV to 20 mV and -13 mV or so,respectively. The effect of different pH and dilution times on stability of formulations were slight. CONCLUSION: The formulations of raloxifene nanoemulsion including positive, negative and near zero Zeta potential were obtained, which have laid a foundation for absorption mechanism study of the raloxifene nanoemulsion.

Research progress on translesion synthesis DNA polymerase ζ-Rev7 in tumor development / 基础医学与临床

Translesion DNA synthesis is a kind of post-replication repair process, which mainly involves DNA polymerase kappa, eta and zeta.Translesion synthesis is a tolerance mechanism of DNA damage inside the cell, in which DNA polymerase zeta plays an important role.DNA polymerase zeta is mainly composed of subunits Rev7 and Rev3, and play a main role of participate in the damage repair in cell metabolism.Rev7(also known as MAD2L2)is a multifunctional protein that can be combined with a variety of proteins to participate in DNA dam-age repair, cell cycle regulation, gene expression and carcinogenesis, which is also involved in the prognosis of various adverse tumors.

Combined immunodeficiency / 中华实用儿科临床杂志

Combined immunodeficiency (CID) is categorized to the first classification from the international union of immunological societies expert committee for primary immunodeficiency.Severe combined immunodeficiency (SCID) is the most fatal disorder for paediatric clinical operation.Without hematopoietic stem cell transplantation,almost all infants would die before 1 year old,few could survive beyond 2 years old.Hypomorphic mutations in SCID genes can lead to atypical phenotypes.The two special SCID should be focused,Omenn syndrome and graft-versus-host disease,which are caused by expension of autologous and maternal activated and memory T lymphocytes,respectively.Patients with radiosensitive-CID usually present later on life,for whom treatment should be monitored carefully.CID caused by T cells with normal development and inborn error was hotspot research field for example zeta chain-associated protein 70 kDa deficiency.More attention should be paid to CID associated with syndromes for example dedicator of cytokinesis 8 deficiency.Now,the pathogenesis,molecular,clinical,laboratory features and treatment and prognosis are described,in order to support clues for paediatrician's clinical practice.

Efficient immobilization of agarase using carboxyl-functionalized magnetic nanoparticles as support

Background: A simple and efficient strategy for agarase immobilization was developed with carboxyl-functionalized magnetic nanoparticles (CMNPs) as support. The CMNPs and immobilized agarase (agarase-CMNPs) were characterized by transmission electron microscopy, dynamic light scattering, vibrating sample magnetometry, scanning electron microscopy, X-ray diffraction, thermogravimetric analysis, and zeta-potential analysis. The hydrolyzed products were separated and detected by ESI-TOF-MS. Results: The agarase-CMNPs exhibited a regular spherical shape with a mean diameter of 12 nm, whereas their average size in the aqueous solution was 43.7 nm as measured by dynamic light scattering. These results indicated that agarase-CMNPs had water swelling properties. Saturation magnetizations were 44 and 29 emu/g for the carriers and agarase-CMNPs, respectively. Thus, the particles had superparamagnetic characteristics, and agarase was successfully immobilized onto the supports. Agaro-oligosaccharides were prepared with agar as substrate using agarase-CMNPs as biocatalyst. The catalytic activity of agarase-CMNPs was unchanged after six reuses. The ESI-TOF mass spectrogram showed that the major products hydrolyzed by agarase-CMNPs after six recycle uses were neoagarotetraose, neoagarohexaose, and neoagarooctaose. Meanwhile, the end-products after 90 min of enzymatic treatment by agarase-CMNPs were neoagarobiose and neoagarotetraose. Conclusions: The enhanced agarase properties upon immobilization suggested that CMNPs can be effective carriers for agarase immobilization. Agarase-CMNPs can be remarkably used in developing systems for repeated batch production of agar-derived oligosaccharides.

Effects of Elicitors on Fucoxanthin Production and ZDS Gene Expression in Phaeodactylum tricornutum / 中国药学杂志

OBJECTIVE: To explore the effects of methyl jasmonic acid(MeJA), arachidonic acid(AA) and acetylsalicylic acid(ASA) on fucoxanthin production and PtZDS gene expression in Phaeodactylum tricornutum. METHODS: The full length cDNA of PtZDS gene in P. tricornutum was obtained by HiSeq™ Illumina 2000 and bioinformatics analysis. HPLC was used to determine the production of fucoxanthin in Phaeodactylum tricornutum, and RT-PCR was used to determine the expression level of PtZDS. RESULTS: The total length of PtZDS gene was 1 905 bp, containing an open reading frame of 1 776 bp encoding 591 amino acids. The deduced amino acid sequence analysis showed that PtZDS protein contained a typical amino oxidase domain, NAD(P)-binding Rossmann-like domain and a chloroplastic transit peptide sequence. The phylogenetic analysis demonstrated that PtZDS was homologous with Thalassiosira pseudonana CCMP1335(76%). Under the treatment of 0.1 mg·L-1 AA, 25 mg·L-1 ASA and 100 μmol·L-1MeJA, the highest yield of unit cell fucoxanthin content was achieved. Upon the observation of PtZDS regulation expression, the expression level of PtZDS reached a peak value under the treatment of 0.1 mg·L-1 AA, 50 μmol·L-1MeJA and 10 mg·L-1 ASA. CONCLUSION: The expression of PtZDS gene has certain relationship with the fucoxanthin synthesis of P. tricornutum. Under the treatment of 100 μmol·L-1 MeJA, the ability of synthetic fucoxanthinis the strongest in P. tricornutum.

Adverse effect of beta-tricalcium phosphate with zeta potential control in repairing critical defects in rats' calvaria / Efeito adverso do beta-fosfato tricálcico com controle de potencial zeta no reparo de defeitos críticos em calvária de ratos

To evaluate whether a new biphasic cement composed of calcium sulfate and beta tricalcium phosphate with zeta potential control could induce or lead to bone neoformation in critical defects. METHODS: A critical defect of diameter 8 mm was made in the calvaria of forty male Wistar rats. In the Test Group (n = 20), the defects were filled with cement. In the Control Group (n = 20), the defect was not filled and only coagulum was present. The animals were sacrificed 7, 14, 21 and 42 days after the operation. Calvaria specimens were subjected to microtomography and were then prepared for histological analysis. The analyses included morphological assessment on the histopathology of the repair; comparative morphometric evaluation of the area of formation of bone trabeculae between the groups; and histochemical staining by means of tartrate-resistant phosphatase (TRAP) in order to identify osteoclasts. RESULTS: Microtomographic images of the defects filled by the cement did not show any decrease in area over the course of postoperative evolution. In the Test Group, the material continued to present a foreign-body response until the last observational periods. Histomorphological analysis showed that there were more significant groupings of giant cells in the Test Group and greater maturity of neoformed bone in the Control Group. Exogenous material was also present. Histomorphometric analysis showed that in the Control Group, the total area of bone neoformation was significantly greater (p = 0.009) and grew progressively. The giant cells presented a positive reaction to TRAP but no osteoclasts were observed. CONCLUSION: The ceramic cement did not induce or lead to bone neoformation from the microtomographic or histological point of view.

Avaliar se um novo cimento bifásico composto por sulfato de cálcio e beta fosfato tricálcico com controle de potencial zeta poderia induzir ou conduzir a neoformação óssea em defeitos críticos. MÉTODOS: Foi feito um defeito crítico de 8 mm de diâmetro na calvária de 40 ratos Wistar machos. No grupo teste (n = 20) os defeitos foram preenchidos pelo cimento. No grupo controle (n = 20) os defeitos não foram preenchidos, permaneceu apenas o coágulo. Os animais sofreram eutanásia em 7, 14, 21 e 42 dias do pós-operatório. Espécimes da calvária foram microtomografados e posteriormente preparados para análise histológica. As análises incluíram a avaliação morfológica da histopatologia do reparo e a avaliação morfométrica da área de formação das trabéculas ósseas comparativamente entre os grupos e coloração histoquímica por meio da fosfatase tartrato-resistente (TRAP) para identificação de osteoclastos. RESULTADOS: As imagens microtomográficas dos defeitos preenchidos pelo cimento não apresentaram diminuição da área de acordo com a progressão dos períodos pós-operatórios. No grupo teste houve permanência do material e resposta corpo estranho até os últimos períodos de observação. A histomorfologia mostrou agrupamentos mais expressivos de células gigantes no grupo teste e osso neoformado mais maduro no grupo controle e comprovou a presença de material exógeno. Na histomorfometria, a área total de neoformação óssea foi significativamente maior (p = 0,009) e crescente no grupo controle. As células gigantes apresentaram expressão histoquímica positiva para TRAP e não foram observados osteoclatos. CONCLUSÃO: O cimento cerâmico não induziu ou conduziu a neoformação óssea sob o ponto de vista microtomográfico e histológico.

Lipoprotein (a) Particles Characterization by Dynamic Light Scattering.

Lp(a) is a novel cardiovascular risk factor resembling an LDL particle. It includes a copy of apolipoprotein (a) [apo(a)], whose molecular weight is dependent on the number of genetically encoded kringle IV type 2 (KIV-2) repeats and inversely related with Lp(a) plasma concentration and risk. The reason for this inverse relationship is unclear and, particularly, there are no data regarding the size of Lp(a) particles carrying apo(a) with different molecular weights. The aim of the present work was to explore if a relationship existed between apo(a) molecular weight and particles size in Lp(a) samples carrying 20, 25 and 28 KIV-2 repeats (K20, K25 and K28, respectively). Dynamic Light Scattering (DLS) measurements were performed on affinity-purified Lp(a). A preliminary finding was that particles were typically distributed into three different size groups instead of the single one expected. No difference in average particle size between Lp(a) carrying different apo(a) isoforms was found. However, the percentage of medium-sized particles in each sample was found to be inversely related to the number of KIV-2 repeats (R2=0.99), with a clear predominance in K20 (58.53%). These data deserve further investigations, as they might be potentially relevant to explain the pathogenic role of low molecular weight Lp(a) isoforms.

Effects of Tussilago farfara by Grinding Dispersion Treatment on the Dispersion Stability of Xiao’er Feike Granules in Water / 中国药房

OBJECTIVE:To improve the dispersion stability in water of Tussilago farfara powder,and to improve compliance of Xiao’er feike granules. METHODS:The effects of 4 kinds of dispersion stabilizer (sodium hexametaphosphate, dextrin, PEG4000 and lecithin) on dispersion stability of suspension in water were investigated during the grinding of T. farfara using rate of absorbance change(β)and Zeta potential as index;IR spectrum of samples were characterized. Using original formulation with-out dispersion stabilizer as control,the dispersion stability of new formulation granules in water were analyzed comparatively after adding dispersion stabilizer. RESULTS:Among 4 kinds of dispersion stabilizer,β of sample prepared by sodium hexametaphos-phate was the lowest,while Zeta potential of it was the highest;compared with original T. farfara,β of T. farfara grinded with 2.5% sodium hexametaphosphate decreased by 16.8%,and Zeta potential absolute value increased by 29.4%;no new peak was found in IR spectrum. Compared with control granules,granules suspension prepared by new formulation had lower β and higher Zeta potential absolute value (P<0.01);particle size was 30 μm and no large particle aggregation was found;β was less than 5.0% within 20 s sedimentation. CONCLUSIONS:During the preparation of Xiao’er feike granules,the application of sodium hexametaphosphate in the grinding of T. farfara powder can improve the dispersion stability of granules in water and the compliance of the preparation.

Relationship between phospholipase C zeta immunoreactivity and DNA fragmentation and oxidation in human sperm

OBJECTIVE: The study aimed to evaluate the feasibility and reproducibility of measuring phospholipase C zeta (PLCzeta) using immunostaining in human sperm and to investigate the relationship between PLCzeta immunoreactivity and DNA fragmentation and oxidation in human sperm. METHODS: Semen samples were obtained from participants (n=44) and processed by the conventional swim-up method. Sperm concentration, motility, normal form by strict morphology, DNA fragmentation index assessed by terminal deoxynucleotidyl transferase dUTP nick end labeling method and immunofluorescent expression for 8-hydroxy-2'-deoxyguanosine (8-OHdG) and PLCzeta were assessed. RESULTS: When duplicate PLCzeta tests were performed on two sperm samples from each of the 44 participants, similar results were obtained (74.1+/-9.4% vs. 75.4+/-9.7%). Two measurements of PLCzeta were found to be highly correlated with each other (r=0.759, P<0.001). Immunoreactivity of PLCzeta was not associated with donor's age, sperm concentration, motility, and the percentage of normal form as well as DNA fragmentation index. However, immunoreactivity of PLCzeta showed a significant negative relationship with 8-OHdG immunoreactivity (r=-0.404, P=0.009). CONCLUSION: Measurement of PLCzeta by immunostaining is feasible and reproducible. Lower expression of PLCzeta in human sperm may be associated with higher sperm DNA oxidation status.

Optimization of rutaecarpine solid lipid nanoparticles by central composite design and response surface methodology / 中草药

Objective: To optimize the prescription of rutaecarpine solid lipid nanoparticles (Rut-SLN). Methods: Using the film-ultrasound method to lining-up the Rut-SLN, with the entrapment efficiency (EE), Zeta potential, and the average particle size as the evaluation indexes, using central composite design to inspect the effects of glycerol monostearate/drug quality ratio (A), soybean lecithin for injection/glycerol monostearate mass ratio (B), Poloxamer 188 (C) on three factors of the EE, Zeta potential, and average particle size. Prediction and analysis for selecting the best prescription condition were carried out by using the response surface method. Results: According to the optimized prescription, the EE, Zeta potential, and the average particle size of Rut-SLN was respectively 84.27%, 122.6 nm, and -20.7 mV. Conclusion: The optimal prescription of Rut-SLN has better stability, feasibility, and high EE, which is suitable for the production.

O efeito do cimento composto de sulfato de cálcio e beta fosfato tricálcico com controle de potencial zeta sobre o reparo de defeitos ósseos críticos em calvária de ratos / The effect of calcium sulfate and beta-tricalcium phosphate composite with zeta potential control on the healing process of bone critical defects in rats

Nos defeitos bucomaxilofaciais, a intervenção cirúrgica utilizando enxertos ou substi-tutos ósseos é indicada para reestabelecer a forma e a função perdidas. Nesse con-texto, enxertos auto?genos e alo?genos te?m sido substituídos por biomateriais osteo-condutores e reabsorvíveis. O objetivo deste trabalho foi avaliar por meio de micro-tomografia e dos aspectos histológicos do reparo ósseo, se um novo cimento bifási-co composto por sulfato de cálcio e beta fosfato tricálcico com controle de potencial zeta, poderia induzir ou conduzir a neoformação óssea em defeitos críticos, produzi-dos em calvárias de ratos. Foi realizado um defeito crítico de 8mm de diâmetro na calvária de 40 ratos Wistar machos. No grupo teste (n=20) os defeitos foram preen-chidos pelo cimento. No grupo controle (n=20) os defeitos não foram preenchidos e permaneceram apenas com o coágulo. Os animais sofreram eutanásia em 7, 14, 21 e 42 dias do pós operatório. Espécimes da região da ferida foram microtomografa-dos e posteriormente as amostras foram preparadas para análise histológica. A aná-lise histomorfológica incluiu a avaliação morfológica da histopatologia do reparo, a avaliação morfométrica da área de formação das trabéculas ósseas comparativa-mente entre os grupos. Realizamos ainda a coloração com fosfatase tartrato-resistente (TRAP) para identificação de osteoclastos...

Surgical intervention employing grafts and bone substitutes is the best choice in oral and maxillofacial bone defects reconstruction for structural and functional lost. Re-garding this, autogenous and alogenous grafts have been used as osteocondutive and resorbable biomaterials. The aim of this study was to evaluate if a new bone bi-phasic composite of calcium sulfate and beta tricalcium phosphate with zeta potential control could induce or conduct bone formation in rats' calvarias critical defects mod-el. Forty male Wistar rats underwent 8mm diameter calvaria perforation under gen-eral anesthesia. Animals were randomly allocated to group test (n=20), when the de-fects were filled with the biphasic phosphate and group control (n=20) when the wound was left just with blood clot. Animals underwent euthanasia 7, 14, 21 and 42 days after surgery. Bone calvaria specimens underwent microtomography and histo-logical processing for analysis. Histomorphological and histomorphometry were per-formed regarding aspects of bone healing evolution and new bone total area within the defect. Additionally, histological samples were tartrate-resistant phosphatase (TRAP) stained for osteoclasts identification...

Formulation and evaluation of nanoparticles containing artemisinin HCL.

The present study deals with the formulation and evaluation of Artemisinin HCl nanoparticles. Artemisinin is a sesquiterpene lactone chemical extract from Artemisia annua (sweet wormwood), is poorly soluble in water and a fast-acting blood schizonticide effective in treating the acute attack of malaria (including chloroquine – resistant and celebral malaria). Artemisinin are effective against multi-resistant strains of P. falciparum. The purpose of the present work is to minimize the dosing frequency, taste masking and toxicity and to improve the therapeutic efficacy by formulating Artemisinin HCl nanoparticles. Artemisinin HCl nanoparticles were formulated by solvent evaporation method using polymer poly(ε-caprolactone) with five different formulations. Nanoparticles were characterized by determining its particle size, polydispersity index, drug entrapment efficiency, particle morphological character and drug release. The particle size ranged between 100nm to 240nm. Drug entrapment efficacy was > 99%. The in-vitro release of nanoparticles were carried out which exhibited a sustained release of Artemisinin HCl from nanoparticles up to 24hrs. The results showed that nanoparticles can be a promising drug delivery system for sustained release of Artemisinin HCl.

Expression,purification and identification of I278T-mutant human cystathionine βsynthase / 国际检验医学杂志

Objective To investigate the expression and purification I278T-mutant human cystathionineβsynthase(CBS) in E . coli .Methods Site-directed mutagenesis by overlap extension using the polymerase chain reaction (PCR) was employed to construct mutant plasmids pGEX4T-1-CBS(I278T) ,which was induced and expressed in a medium containing 3% ethanol ,purified by affinity chromatography to obtain mutated CBS (I278T) protein .The activity ,UV-visible absorption spectroscopy ,protein particle size and Zeta potential of the purified protein were measured .Results Plasmid pGEX4T-1-CBS(I278T) was successfully constructed .The yield ,the specific activity and activity recovery of purified mutant CBS (I278T ) protein were 2 .3 mg/L ,21 .4 U/mg and 22 .6% .S-adenosylmethionine(AdoMet) with final concentration of 1 mmol/L showed no activation toward mutant CBS (I278T) protein .Ac-cording to UV-visible absorption spectroscopy analysis ,purified mutant CBS(I278T) had characteristic absorption peaks at 429 nm and 550 nm for heme-binding proteins .Protein average particle size was 7 .5 -10 .1 nm ,mainly in the form of tetramers ,and Zeta potential was - 16 .3 mV .Conclusion The methods of expression ,purification and identification of I278T-mutant human cystathionineβsynthase in E .coli were successfully established .

Knockdown of 14-3-3zeta enhances radiosensitivity and radio-induced apoptosis in CD133+ liver cancer stem cells

14-3-3zeta is related to many cancer survival cellular processes. In a previous study, we showed that silencing 14-3-3zeta decreases the resistance of hepatocellular carcinoma (HCC) to chemotherapy. In this study, we investigated whether silencing 14-3-3zeta affects the radioresistance of cancer stem-like cells (CSCs) in HCC. Knockdown of 14-3-3zeta decreased cell viability and the number of spheres by reducing radioresistance in CSCs after gamma-irradiation (IR). Furthermore, the levels of pro-apoptotic proteins were upregulated in CSCs via silencing 14-3-3zeta after IR. These results suggest that 14-3-3zeta knockdown enhances radio-induced apoptosis by reducing radioresistance in liver CSCs.