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1.
Trop Doct ; 54(2): 172-175, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38311934

RESUMO

Liver abscess (LA) is a significant health concern worldwide, particularly in tropical regions such as India, and is usually pyogenic or amoebic in origin. In rare cases it can be caused by parasites. We present two children with difficult-to-treat LAs, revealing underlying parasitic infections as the causative agents, implicated by eosinophilia, elevated immunoglobulin-E levels and exposure to domestic animals. In the first case, disseminated echinococcosis was diagnosed through imaging, serology and histopathology. The second case showed a relationship between LAs and Toxocara infection, evidenced by microscopic stool examination of a household cat.


Assuntos
Equinococose , Eosinofilia , Abscesso Hepático , Doenças Parasitárias , Toxocaríase , Animais , Gatos , Criança , Humanos , Abscesso Hepático/diagnóstico , Abscesso Hepático/patologia
2.
Int J Appl Basic Med Res ; 13(2): 95-100, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37614835

RESUMO

Background: Hypertensive disorders of pregnancy affect 3%-5% of all pregnancies, contributing immensely to maternal morbidity and mortality. According to the WHO, the incidence of deaths due to preeclampsia and eclampsia in developing and developed countries is 2.8% and 0.4%, respectively. Lactate dehydrogenase (LDH) and uric acid are good predictors of disease severity. Aim: This study aims to determine the fetomaternal outcome in relation to abnormal serum levels of LDH and uric acid. Materials and Methods: A cross-sectional study was carried out in 1200 patients with preeclampsia and eclampsia at a tertiary care center over 2 years. Patients were divided into - Group A: patients with normal LDH (≤300 IU/L) and uric acid (<6 mg/dl) (n = 300). Group B: patients with abnormal LDH and uric acid (n = 900), who were further divided into mild and severe preeclampsia and eclampsia. Abnormal serum values were stratified into groups for easier comparison. The results were compared in terms of maternal and perinatal outcomes. Results: The incidence of preeclampsia and eclampsia in our study is 3.14% and 1.57%, respectively. Significant changes in LDH and uric acid were associated with increased severity of the disease (LDH - 1116.94 ± 4.78; uric acid - 9.2 ± 2.89). Higher incidence of maternal and fetal complications was seen with severe preeclampsia and eclampsia with LDH >800 IU/L and uric acid >6 mg/dl. Conclusion: Standard antenatal follow-up should be carried out for early detection and prevention of preeclampsia, with strict monitoring of serum uric acid level and LDH. This may reduce the maternal and fetal complications due to preeclampsia.

3.
J Family Med Prim Care ; 11(9): 5327-5331, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36505559

RESUMO

Introduction: Cancer cervix is a major health problem responsible for causing a higher mortality rate in women worldwide; the exponential increase in such cases can be reduced by early screening of women. The cytology-based cervical screening had a higher success rate in reducing the incidence of cervical cancer. The present study aimed to evaluate the use of Pap smear screening to find cytological abnormalities and precancerous lesions. Materials and Methods: Sexually active women over 21 years of age were enrolled for the study. A detailed history was taken on the preformed proforma, and all were subjected to vaginal examination. Samples for Pap smear were taken with the help of Ayre spatula and immediately spread over a marked grease-free glass slide and dipped into 95% ethyl alcohol fixative for cytological examination. Results: Most of the abnormality of the epithelial cells found was in the age range of 31-50 years, and most of them were multiparous. 47.92% of the women had a chief complaint of vaginal discharge, an irregular menstrual cycle in 11.07%, and abdominal pain in 7.83%, while 30.41% were asymptomatic. Women found negative for intraepithelial neoplasia were 82.94%, while 13.36% had an inflammatory smear. 0.92% atypical squamous cells of undetermined significance (ASCUS), 2.78% Low-grade squamous intraepithelial lesion (LSIL) were found, no woman had High-grade squamous intraepithelial lesion (HSIL). Conclusion: Pap smear is a simple, cost-effective, non-invasive, and easy to perform tool for early detection of precancerous lesions, and it is evident that every woman above the age of 25-30 years must be recommended for cervical screening.

4.
Diagnostics (Basel) ; 12(6)2022 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-35741305

RESUMO

Hospital payments depend on the Medicare Severity Diagnosis-Related Group's estimated cost and the set of diagnoses identified during inpatient stays. However, over-coding and under-coding diagnoses can occur for different reasons, leading to financial and clinical consequences. We provide a novel approach to measure diagnostic coding intensity, built on commonly available administrative claims data, and demonstrated through a 2019 pneumonia acute inpatient cohort (N = 182,666). A Poisson additive model (PAM) is proposed to model risk-adjusted additional coded diagnoses. Excess coding intensity per patient visit was estimated as the difference between the observed and PAM-based expected counts of secondary diagnoses upon risk adjustment by patient-level characteristics. Incidence rate ratios were extracted for patient-level characteristics and further adjustments were explored by facility-level characteristics to account for facility and geographical differences. Facility-level factors contribute substantially to explain the remaining variability in excess diagnostic coding, even upon adjusting for patient-level risk factors. This approach can provide hospitals and stakeholders with a tool to identify outlying facilities that may experience substantial differences in processes and procedures compared to peers or general industry standards. The approach does not rely on the availability of clinical information or disease-specific markers, is generalizable to other patient cohorts, and can be expanded to use other sources of information, when available.

5.
Int J Biol Macromol ; 210: 107-122, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35525494

RESUMO

Transgenic crops would serve as a tool to overcome the forthcoming crisis in food security and environmental safety posed by degrading land and changing global climate. Commercial transgenic crops developed so far focus on single stress; however, sustaining crop yield to ensure food security requires transgenics tolerant to multiple environmental stresses. Here we argue and demonstrate the untapped potential of ribosome inactivating proteins (RIPs), translation inhibitors, as potential transgenes in developing transgenics to combat multiple stresses in the environment. Plant RIPs target the fundamental processes of the cell with very high specificity to the infecting pests. While controlling pathogens, RIPs also cause ectopic expression of pathogenesis-related proteins and trigger systemic acquired resistance. On the other hand, during abiotic stress, RIPs show antioxidant activity and trigger both enzyme-dependent and enzyme-independent metabolic pathways, alleviating abiotic stress such as drought, salinity, temperature, etc. RIPs express in response to specific environmental signals; therefore, their expression obviates additional physiological load on the transgenic plants instead of the constitutive expression. Based on evidence from its biological significance, ecological roles, laboratory- and controlled-environment success of its transgenics, and ethical merits, we unravel the potential of RIPs in developing transgenic plants showing co-tolerance to multiple environmental stresses.


Assuntos
Secas , Proteínas Inativadoras de Ribossomos , Produtos Agrícolas/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Proteínas Inativadoras de Ribossomos/metabolismo , Estresse Fisiológico/genética
6.
J Environ Manage ; 256: 109908, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31822458

RESUMO

Phenolics drive the global economy, but they also pose threats to soil health and plant growth. Enzymes like peroxidase have the potential to remove the phenolic contaminants from the wastewater; however, their role in restoring soil health and improving plant growth has not yet been ascertained. We fractionated efficient peroxidases (MPx) from leaves of an invasive species of Mesquite, Prosopis juliflora, and demonstrated its superiority over horseradish peroxidase (HRP) in remediating phenol, 3-chlorophenol (3-CP), and a mixture of chlorophenols (CP-M), from contaminated soil. MPx removes phenolics over a broader range of pH (2.0-9.0) as compared with HRP (pH: 7.0-8.0). In soil, replacing H2O2 with CaO2 further increases the phenolic removal efficiency of MPx (≥90% of phenol, ≥ 70% of 3-CP, and ≥90% of CP-M). MPx maintains ~4-fold higher phenolic removal efficiency than purified HRP even in soils with extremely high contaminant concentration (2 g phenolics/kg of soil), which is desirable for environmental applications of enzymes for remediation. MPx treatment restores soil biological processes as evident by key enzymes of soil fertility viz. Acid- and alkaline-phosphatases, urease, and soil dehydrogenase, and improves potential biochemical fertility index of soil contaminated with phenolics. MPx treatment also assists the Vigna mungo test plant to overcome toxicant stress and grow healthy in contaminated soils. Optimization of MPx for application in the field environment would help both in the restoration of phenolic-contaminated soils and the management of invasive Mesquite.


Assuntos
Prosopis , Poluentes do Solo , Biodegradação Ambiental , Peróxido de Hidrogênio , Espécies Introduzidas , Peroxidases , Fenóis , Solo
7.
J Ethnopharmacol ; 219: 91-102, 2018 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-29555410

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Viscum articulatum Burm. f. (leafless mistletoe) has been used in traditional system of medicines in India, China, Taiwan, Cambodia, Laos, and Vietnam, to treat blood-related diseases and various inflammatory and degenerative diseases including cancer. Anticancer activities of some phytomolecules purified from Viscum articulatum Burm. f. have been tested. However scientific evidence for the anticancerous potential of aqueous extract of V. articularum (VAQE) used in traditional medicine is lacking. AIM OF THE STUDY: To study the antiproliferative and apoptotic effect of VAQE on Jurkat E6.1 and THP1 leukemia cells. MATERIALS AND METHODS: The aqueous extract of the whole plant of Viscum articulatum Burm. f. was prepared in phosphate buffer saline. In VAQE, total soluble protein was estimated using Bradford's dye-binding assay; flavonoid content was determined using aluminum chloride colorimetric assay; and phenolic content was estimated following Folin-Ciocalteu colorimetric assay. XTT cell viability assay was used to test VAQE induced cytotoxicity in Jurkat E6.1 and THP1 leukemia cells and peripheral blood mononuclear cells (PBMC). The effect of VAQE on cell cycle progression was analyzed by PI staining using flow cytometry. Annexin-V-FITC/PI differential staining method was used for detecting the onset of apoptosis in leukemia cells. Rhodamine 123 dye was used to detect the change in mitochondrial membrane potential (MMP) using flow cytometry. DCF-DA fluorescence dye was used to estimate the level of reactive oxygen species (ROS). The ROS inhibitors were used to evaluate the role of ROS in mediating DNA degradation in VAQE-treated leukemia cells. The molecular mechanisms underlying VAQE induced apoptosis induction was studied by analyzing the expression of anti-apoptotic (Bcl-2) and pro-apoptotic (Bax) proteins, caspase-8 and caspase-3 enzymes using western blot. Diphenylamine (DPA) assay was used to determine the DNA fragmentation and conclusion of apoptosis. RESULTS: VAQE triggered cytotoxic effect on Jurkat E6.1 (IC50-2.4 µg/ml; 24 h) and THP1 (IC50-1.0 µg/ml; 24 h) cells in a dose- and time-dependent manner. The apoptosis induction and G2/M arrest of the cell cycle are the cause of VAQE-induced cytotoxicity in leukemia cells. The apoptosis in VAQE-treated Jurkat E6.1 and THP1 cells was mediated via a reduction in MMP, elevation of intracellular ROS, decreased expression of the anti-apoptotic (Bcl-2) and increased expression of the pro-apoptotic (Bax) protein, activation of caspase-8 and caspase-3 and DNA fragmentation. CONCLUSION: VAQE has a high efficacy to exert a cytotoxic effect in Jurkat E6.1 and THP1 cells and to induce apoptosis and G2/M cell cycle arrest. VAQE induces extrinsic pathway of apoptosis in both the leukemia cell lines via disruption of MMP, intracellular ROS imbalance, increased ratio of Bax/Bcl-2, activation of caspase-8, caspase-3 and ROS-mediated DNA fragmentation. The knowledge gained from the outcomes of the study may encourage the identification of novel chemotherapeutic agent from Viscum articulatum Burm. f. to treat leukemia.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Extratos Vegetais/farmacologia , Viscum , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/fisiologia , Pontos de Checagem do Ciclo Celular/fisiologia , Proliferação de Células/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Relação Dose-Resposta a Droga , Humanos , Células Jurkat , Extratos Vegetais/isolamento & purificação , Células THP-1
8.
J Hazard Mater ; 334: 201-211, 2017 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-28412630

RESUMO

The present study examines mesquite (Prosopis juliflora), an invasive species, to yield peroxidase that may reduce hazards of phenolics to living organisms. As low as 0.3U of low-purity mesquite peroxidase (MPx) efficiently remove phenol and chlorophenols (90-92%) compared with Horseradish peroxidase (HRP) (40-60%). MPx shows a very high removal efficiency (40-50%) at a wide range of pH (2-9) and temperature (20-80°C), as opposed to HRP (15-20%). At a high-level of the substrate (2.4mM) and without the addition of PEG, MPx maintains a significant phenolic removal (60-≥92%) and residual activity (∼25%). It proves the superiority of MPx over HRP, which showed insignificant removal (10-12%) under similar conditions, and no residual activity even with PEG addition. The root elongation and plant growth bioassays confirm phenolic detoxification by MPx. Readily availability of mesquite across the countries and easy preparation of MPx from leaves make this tree as a sustainable source for a low-technological solution for phenol remediation. This study is the first step towards converting a biological wound of invasive species into wisdom and strength for protecting the environment from phenol pollution.


Assuntos
Espécies Introduzidas , Peroxidase/metabolismo , Fenol/isolamento & purificação , Prosopis/enzimologia , Poluentes Químicos da Água/isolamento & purificação , Biodegradação Ambiental , Peroxidase do Rábano Silvestre/metabolismo , Concentração de Íons de Hidrogênio , Inativação Metabólica , Fenol/metabolismo , Fenol/toxicidade , Desenvolvimento Vegetal/efeitos dos fármacos , Raízes de Plantas/enzimologia , Temperatura , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/toxicidade
9.
Indian Pediatr ; 54(2): 128-131, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-28285283

RESUMO

OBJECTIVE: To study the factors associated with the subsequent (over next 9 years) full-text publication of papers presented at the 44th National Conference of Indian Academy of Pediatrics (PEDICON), 2007. METHODS: All papers presented at PEDICON 2007 were searched for subsequent full-text publication over the next 9 years in English-language journals by an internet-based search. The published papers were compared with the conference-abstracts. RESULTS: 74 (16%) of the 450 abstracts presented were subsequently published; 61 (82.4%) in Medline-indexed journals. Majority (50, 67.6%) of the papers was published within the first 36 mo in journals with mean (SD) impact factor of 2.62 (1.63). The factors significantly associated with subsequent publication were papers presented as award papers (P<0.001), those reporting on Interventional trials (P<0.001), and those from medical colleges (P<0.05). On comparison of the conference abstracts with the subsequently published full-papers, 55% had a change in title; authors were changed in 65%, and participants' numbers were dissimilar in 8.6%. CONCLUSION: There is a need to identify the factors responsible for this low rate of subsequent publication, and interventions to improve it both at institutional and researchers' level.


Assuntos
Pediatria/organização & administração , Publicações/estatística & dados numéricos , Humanos , Índia , Fator de Impacto de Revistas , Editoração , Sociedades Médicas
10.
Interdiscip Sci ; 9(2): 332-340, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26947220

RESUMO

Dihydrofolate reductase enzyme has been an attractive biological target for the design and development of antimicrobials. Considering this, we have attempted to identify novel dihydrofolate reductase inhibitors through our well-defined in silico and in vitro work flow. An accurate and predictive pharmacophore model comprising of one hydrogen bond acceptor, two hydrophobic and one ring aromatic was developed and utilized as a query to search the National Cancer Institute and Maybridge database leading to retrieval of various compounds which were filtered on the basis of estimated activity, fit value and Lipinski's violation. Selected hits NSC3423, KM09759, NSC391, NSC2091 and HTS00630 were subjected to docking studies which resulted into visualization of potential interaction capabilities of hits in line to pharmacophoric features. The identified hits were evaluated for in vitro antimicrobial potential, and the results revealed that among all the five hits, NSC3423 is the most potent compound with activity against E. coli, P. aeruginosa, S. aureus, B. substilis, A. niger and F. oxysporum. On the other hand, KM09759, NSC391, NSC2091 and HTS00630 showed varying degree of activities against gram-positive, gram-negative and fungal strains.


Assuntos
Anti-Infecciosos/farmacologia , Simulação de Acoplamento Molecular , Inibidores Enzimáticos/farmacologia , Escherichia coli/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Relação Estrutura-Atividade , Tetra-Hidrofolato Desidrogenase/metabolismo
11.
Mol Cell Biochem ; 426(1-2): 87-99, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27868169

RESUMO

Leukemia is among the most aggressive and prevalent human malignant carcinoma. Chemotherapy is the preferred therapeutic strategy; however, recurrence of cancer and non-selective cytotoxicity are the major concerns. Unlike synthetic chemotherapeutic agents, mistletoe ribosome-inactivating protein (RIP) displays anti-tumor function in various types of cancers. However, its effect on leukemia cells is little explored. In this study, we assessed the impact of Viscum articulatum RIP (Articulatin-D) on the survival of acute T-cell leukemia cells and the involved molecular and cellular mechanisms. Cell proliferation assay showed that Articulatin-D suppressed the viability of leukemia cells selectively. We further confirmed that the elevation of mitochondrial membrane potential and exposure of phosphatidylserine are the early events of apoptosis induction in Articulatin-D-treated Jurkat cells. Subsequently, we found that Articulatin-D treatment induces apoptosis in Jurkat cells in a time- and concentration-dependent manner. In conclusion, we provided evidence that Articulatin-D efficiently activates caspase-8 involved in extrinsic pathway of apoptosis induction, which ultimately results in caspase-3-dependent DNA fragmentation of Jurkat cells. Further evaluation of Articulatin-D in cell culture and animal models may provide novel information on selective cytotoxicity to acute T-cell leukemia and its involvement in targeting tumor cell survival pathways.


Assuntos
Apoptose/efeitos dos fármacos , Caspase 8/metabolismo , Proliferação de Células/efeitos dos fármacos , Preparações de Plantas/farmacologia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamento farmacológico , Proteínas Inativadoras de Ribossomos Tipo 2/farmacologia , Toxinas Biológicas/farmacologia , Viscum/química , Fragmentação do DNA/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Humanos , Células Jurkat , Preparações de Plantas/química , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Proteínas Inativadoras de Ribossomos Tipo 2/química , Toxinas Biológicas/química
12.
Regen Med ; 11(6): 571-87, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27549369

RESUMO

Bone tissue engineering (BTE) intends to restore structural support for movement and mineral homeostasis, and assist in hematopoiesis and the protective functions of bone in traumatic, degenerative, cancer, or congenital malformation. While much effort has been put into BTE, very little of this research has been translated to the clinic. In this review, we discuss current regenerative medicine and restorative strategies that utilize tissue engineering approaches to address bone defects within a clinical setting. These approaches involve the primary components of tissue engineering: cells, growth factors and biomaterials discussed briefly in light of their clinical relevance. This review also presents upcoming advanced approaches for BTE applications and suggests a probable workpath for translation from the laboratory to the clinic.


Assuntos
Doenças Ósseas/terapia , Regeneração Óssea/fisiologia , Osso e Ossos/citologia , Engenharia Tecidual/métodos , Animais , Humanos
13.
Tissue Eng Part C Methods ; 22(9): 904-13, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27558310

RESUMO

One approach to the development of an artificial graft material could rely on uniform coverage of a resorbable biomaterial with bone extracellular matrix (ECM). To achieve this on the surface of poly(propylene fumarate) (PPF) scaffolds, we selected a growth factor regime of basic fibroblast growth factor (FGF-2) (5 ng/mL), platelet-derived growth factor (PDGF-BB) (40 ng/mL), and epidermal growth factor (EGF) (20 ng/mL) to stimulate proliferation of bone marrow-derived human mesenchymal stem cells (BM-hMSCs). Bone morphogenetic protein (BMP) 4 (50 ng/mL), 6 (50 ng/mL), and 7 (27 ng/mL) in the presence of the following osteogenic substances: dexamethasone (10(-7) M), ß-glycerophosphate (10 mM), and ascorbic acid (50 µg/mL) were chosen to induce differentiation of BM-hMSCs into ECM-secreting osteoblasts. These growth factors were also studied at 10× concentration to determine dose effect. Proliferation was analyzed by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay, scanning electron microscopy (SEM), and toluidine blue staining, whereas differentiation was analyzed through alizarin red S staining and assay, alkaline phosphatase (ALP) staining and assay, and SEM. The proliferation study suggests that a combination of EGF, PDGF-BB, and FGF-2 growth factors at optimal concentration over a period of 1 week exhibits significantly (p = 0.001) higher number of cells (116,024 ± 5165) than these cytokines without EGF (91,706 ± 11,965). Increasing the dosage does not show any significant effect. The BM-hMSC differentiation study results show that ALP enzyme production and mineral deposition increase from day 14 to day 21 in all groups containing BMPs and osteogenic medium. However, mineralization is significantly higher in the BMP-7 group. Furthermore, the feasibility of translating the results from two dimensional thin films to three dimensional-printed PPF scaffolds was determined through uniform initial seeding and spreading of BM-hMSCs. Therefore, we have determined the optimum dose of growth factors for proliferation and differentiation of BM-hMSCs on the surface of PPF scaffolds, which can be used to produce ECM-coated implants for the treatment of bone defects.


Assuntos
Células da Medula Óssea/citologia , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Fumaratos/química , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Células-Tronco Mesenquimais/citologia , Polipropilenos/química , Alicerces Teciduais/química , Células da Medula Óssea/efeitos dos fármacos , Células Cultivadas , Fumaratos/farmacologia , Humanos , Células-Tronco Mesenquimais/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Osteogênese/fisiologia , Polipropilenos/farmacologia , Engenharia Tecidual/métodos
14.
Biomacromolecules ; 17(2): 690-7, 2016 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-26771388

RESUMO

A ring opening polymerization method for synthesizing oligomeric poly(propylene fumarate) (PPF) provides a rapid, and scalable method of synthesizing PPF with well-defined molecular mass, molecular mass distribution (Dm), and viscosity properties suitable for 3D printing. These properties will also reduce the amount of solvent necessary to ensure sufficient flow of material during 3D printing. MALDI mass spectrometry precisely shows the end group fidelity, and size exclusion chromatography (SEC) demonstrates narrow mass distributions (<1.6) of a series of low molecular mass oligomers (700-3000 Da). The corresponding intrinsic viscosities range from 0.0288 ± 0.0009 dL/g to 0.0780 ± 0.0022 dL/g. The oligomers were printed into scaffolds via established photochemical methods and standardized ISO 10993-5 testing shows that the 3D printed materials are nontoxic to both L929 mouse fibroblasts and human mesenchymal stem cells.


Assuntos
Materiais Biocompatíveis/química , Fumaratos/química , Polipropilenos/química , Alicerces Teciduais/química , Animais , Materiais Biocompatíveis/toxicidade , Linhagem Celular , Sobrevivência Celular , Fumaratos/toxicidade , Humanos , Teste de Materiais , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/fisiologia , Camundongos , Polipropilenos/toxicidade , Porosidade
15.
Biomaterials ; 77: 255-66, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26606451

RESUMO

The importance of vascularization in the field of bone tissue engineering has been established by previous studies. The present work proposes a novel poly(propylene fumarate) (PPF)/fibrin composite scaffold for the development of vascularized neobone tissue. The effect of prevascularization (i.e., in vitro pre-culture prior to implantation) with human mesenchymal stem cells (hMSCs) and human umbilical vein endothelial cells (HUVECs) on in vivo vascularization of scaffolds was determined. Five conditions were studied: no pre-culture (NP), 1 week pre-culture (1P), 2 week pre-culture (2P), 3 week pre-culture (3P), and scaffolds without cells (control, C). Scaffolds were implanted subcutaneously in a severe combined immunodeficiency (SCID) mouse model for 9 days. During in vitro studies, CD31 staining showed a significant increase in vascular network area over 3 weeks of culture. Vascular density was significantly higher in vivo when comparing the NP and 3P groups. Immunohistochemical staining of human CD-31 expression indicated spreading of vascular networks with increasing pre-culture time. These vascular networks were perfused with mouse blood indicated by perfused lectin staining in human CD-31 positive vessels. Our results demonstrate that in vitro prevascularization supports in vivo vascularization in PPF/fibrin scaffolds.


Assuntos
Materiais Biocompatíveis/química , Capilares/crescimento & desenvolvimento , Fibrina/química , Fumaratos/química , Organoides/irrigação sanguínea , Polipropilenos/química , Engenharia Tecidual/métodos , Alicerces Teciduais , Animais , Osso e Ossos , Células Cultivadas , Xenoenxertos , Células Endoteliais da Veia Umbilical Humana , Humanos , Hidrogéis/química , Camundongos , Camundongos SCID , Microscopia Confocal , Microscopia de Fluorescência , Molécula-1 de Adesão Celular Endotelial a Plaquetas/biossíntese , Impressão Tridimensional , Esferoides Celulares , Fatores de Tempo
16.
Int J Biol Sci ; 11(11): 1325-36, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26535027

RESUMO

This work studies osteoinduction and bone conduction in polyvinyl alcohol-tetraethylorthosilicate-alginate-calcium oxide (PTAC) biocomposite cryogels along with the synergistic effect of electrical stimulation. In vitro osteoinduction of C2C12 myoblast towards osteogenic lineage is demonstrated through alkaline phosphatase assay, scanning electron microscopy and energy dispersive X-ray spectroscopy. These results were followed by in vivo implantation studies of PTAC biocomposite cryogel scaffolds in the bone conduction chamber model depicting bone formation after 24 days based on immunohistological staining for osteogenic markers, i.e., collagen type I (Col I), osteocalcin (OCN), osteopontin (OPN) and bone sialoprotein (BSP). Further, osteogenic differentiation of murine mesenchymal stem cells was studied with and without electrical stimulation. The q-PCR analysis shows that the electrically stimulated cryogels exhibit ~ 6 folds higher collagen type I and ~ 10 folds higher osteopontin mRNA level, in comparison to the unstimulated cryogels. Thus, PTAC biocomposite cryogels present osteoinductive and osteoconductive properties during in vitro and in vivo studies and support osteogenic differentiation of mesenchymal stem cells under the influence of electrical stimulation.


Assuntos
Criogéis/química , Animais , Colágeno/metabolismo , Estimulação Elétrica , Sialoproteína de Ligação à Integrina/metabolismo , Camundongos , Microscopia Eletrônica de Varredura , Osteocalcina/metabolismo , Osteopontina/metabolismo , Espectrometria por Raios X
17.
Sci Rep ; 5: 13838, 2015 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-26346444

RESUMO

In recent years the DNA minor groove has attracted much attention for the development of anti-malarial agents. In view of this we have attempted to discover novel DNA minor groove binders through in-silico and in-vitro workflow. A rigorously validated pharmacophore model comprising of two positive ionizable (PI), one hydrophobic (HY) and one ring aromatic (RA) features was used to mine NCI chemical compound database. This led to retrieval of many hits which were screened on the basis of estimated activity, fit value and Lipinski's violation. Finally two compounds NSC639017 and NSC371488 were evaluated for their in-vitro anti-malarial activities against Plasmodium falciparum 3D7 (CQ sensitive) and K1 (CQ resistant) strains by SYBR green-I based fluorescence assay. The results revealed that out of two, NSC639017 posses excellent anti-malarial activity particularly against chloroquine resistant strain and moreover NSC639017 also appeared to be safe (CC50 126.04 µg/ml) and selective during cytotoxicity evaluation.


Assuntos
Antimaláricos/farmacologia , Cloroquina/farmacologia , Descoberta de Drogas , Resistência a Medicamentos , Plasmodium falciparum/efeitos dos fármacos , Antimaláricos/química , Cloroquina/química , Testes de Sensibilidade Parasitária
19.
J Colloid Interface Sci ; 431: 139-48, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-24996023

RESUMO

HYPOTHESIS: Plasma polymerization has been vastly employed for bringing changes in the surface functionality of the biomaterials by changing the surface chemistry without affecting the bulk properties. Therefore, we wanted to analyze the effect of plasma polymerization on the cellular response towards biocomposite cryogel surface and expected a positive response as found with the previous biomaterials. EXPERIMENTS: We performed experiments for the incorporation of polyallylamine plasma on the polyvinyl alcohol-tetraethylorthosilicate-alginate-calcium oxide (PTAC) biocomposite cryogel surface. After plasma modification, the plasma coated/modified surfaces were studied at physicochemical level via methods like X-ray photoelectron spectroscopy, scanning electron microscopy, contact angle and rheology analysis. At biological level, analysis was performed through scanning electron microscopy, energy dispersive X-ray spectroscopy, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and alkaline phosphatase (ALP) assay. FINDINGS: In this paper we highlight a different aspect of plasma modification where both physical and chemical characteristics of surface gets altered on modification of PTAC biocomposite cryogels with plasma polymerized allylamine (ppAAm). This further affected the response of human osteoblasts on these modified/coated cryogels when compared to the unmodified/uncoated cryogels, wherein, the human osteoblasts on coated cryogel surface show higher alkaline phosphatase production and delayed mineralization as compared to the uncoated cryogels.


Assuntos
Materiais Revestidos Biocompatíveis , Criogéis , Teste de Materiais , Osteoblastos/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/síntese química , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Criogéis/síntese química , Criogéis/química , Criogéis/farmacologia , Humanos , Osteoblastos/citologia , Poliaminas/química
20.
J Mater Sci Mater Med ; 25(5): 1327-37, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24515863

RESUMO

Bone tissue engineering majorly focuses on the development of biomaterials which have the capability to mimic bone as well as the ability to induce bone formation. To this direction, we have prepared supermacroporous polyvinyl alcohol-TEOS-Agarose-CaCl2 (PTAgC) biocomposite cryogels having a uniform porous structure with an interconnected porosity of 77 ± 0.16 % and pore size of 190 ± 0.78 µm, as determined by scanning electron microscopic and micro-computed tomographic analyses. These biocomposite cryogels show an osteocompatible response towards Saos-2 human osteoblasts as analyzed via MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay, alkaline phosphatase (ALP) assay and cell adhesion behaviour showing a flattened morphology of the cells on the cryogel surface. The property of bioactivity was also observed on the surface of these biomaterials. Further, we also explored the osteoinductive potential of these biocomposite cryogels by the analysis of osteogenic differentiation of C2C12 myoblasts after seeding onto these biocomposite cryogels. The results indicate that these biocomposite cryogels indeed show an osteoinductive potential as we could observe the presence of respective markers for different stages during osteoblast maturation. During early timepoints, higher alkaline phosphatase production via ALP assay and BCIP/NBT staining was observed in the case of biocomposite cryogel seeded cells suggesting the osteoblastic differentiation of C2C12 cells. Whereas, during later timepoints, formation of calcium-phosphate like crystals was confirmed by von-kossa staining, further indicating towards the onset of mineralization phase during osteoblast maturation. Therefore, these results suggest that PTAgC biocomposite cryogels can form an important part of bone tissue engineered biomaterials due to their osteocompatible behaviour and osteoinductive potential.


Assuntos
Substitutos Ósseos/química , Criogéis/química , Osteoblastos/citologia , Osteoblastos/fisiologia , Osteogênese/fisiologia , Álcool de Polivinil/química , Substitutos Ósseos/farmacologia , Cloreto de Cálcio/química , Cloreto de Cálcio/farmacologia , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Criogéis/farmacologia , Estudos de Viabilidade , Humanos , Teste de Materiais , Osteoblastos/efeitos dos fármacos , Álcool de Polivinil/farmacologia , Sefarose/química , Sefarose/farmacologia
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