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1.
Eur J Pharm Biopharm ; 198: 114272, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38537909

RESUMO

Three-dimensional liver bioprinting is an emerging technology in the field of regenerative medicine that aids in the creation of functional tissue constructs that can be used as transplantable organ substitutes. During transplantation, the bioprinted donor liver must be protected from the oxidative stress environment created by various factors during the transplantation procedure, as well as from drug-induced damage from medications taken as part of the post-surgery medication regimen following the procedure. In this study, Silymarin, a flavonoid with the hepatoprotective properties were introduced into the GelMA bioink formulation to protect the bioprinted liver against hepatotoxicity. The concentration of silymarin to be added in GelMA was optimised, bioink properties were evaluated, and HepG2 cells were used to bioprint liver tissue. Carbon tetrachloride (CCl4) was used to induce hepatotoxicity in bioprinted liver, and the effect of this chemical on the metabolic activities of HepG2 cells was studied. The results showed that Silymarin helps with albumin synthesis and shields liver tissue from the damaging effects of CCl4. According to gene expression analysis, CCl4 treatment increased TNF-α and the antioxidant enzyme SOD expression in HepG2 cells while the presence of silymarin protected the bioprinted construct from CCl4-induced damage. Thus, the outcomes demonstrate that the addition of silymarin in GelMA formulation protects liver function in toxic environments.


Assuntos
Acrilamidas , Doença Hepática Induzida por Substâncias e Drogas , Transplante de Fígado , Silimarina , Humanos , Silimarina/metabolismo , Silimarina/farmacologia , Tetracloreto de Carbono , Gelatina , Extratos Vegetais/química , Doadores Vivos , Fígado , Antioxidantes/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/metabolismo
2.
J Cancer Res Ther ; 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38261422

RESUMO

OBJECTIVE: To optimize the patient dose and image quality through quality assurance (QA) of diagnostic x-ray equipment and to ensure compliance with international and national standards in x-ray specification parameters, the use of contactless and quick non-invasive instruments has gained importance. Considering the importance of equipment qualification and the intervention level for equipment management, it is vital to account for uncertainties in the measurement of parameters in diagnostic radiology. However, the limits and measurement uncertainties associated with the parameter measurement are not well established and many technical and scientific literature provide different tolerance values, either as absolute or in terms of percentage. METHODS AND MATERIALS: In this paper, the authors analyze non-invasive multi-parameter detector measurements with the aim to (i) improve the accuracy in measurement of x-ray parameters (kilovoltage, dose, and exposure time); (ii) estimate the uncertainty associated with such measurements; (iii) analyze the tolerance values prescribed by various professional and regulatory bodies and propose an improvised method of reporting the parameters. The approach adopted in this paper takes into account the uncertainties associated with traditional instruments and the subjectivity in the measurements. RESULTS: Estimated uncertainty for kV measurements in the range between 1.45 kV at 40 kV measurements and 4.88 kV at 150 kV measurements. The MU associated with the dose measurement is estimated to be 6.2% at 110 kVp, 100 mA, and 500 msec. Maximum MU estimated at 10 msec exposure time is 4.5% and with MU of 5% deviation added to 9.5%. CONCLUSIONS: The current practice of reporting the measured mean values deviation without considering the inherent measurement uncertainty may not be a correct quantification procedure in QA. This is evident from the case study that 3% addition to the measured kV, 6.2% addition in the measured dose, and 4.5% to the measured time accounts for measurement uncertainty.

3.
Discov Nano ; 18(1): 157, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38112849

RESUMO

The nanosystems for delivering drugs which have evolved with time, are being designed for greater drug efficiency and lesser side-effects, and are also complemented by the advancement of numerous innovative materials. In comparison to the organic nanoparticles, the inorganic nanoparticles are stable, have a wide range of physicochemical, mechanical, magnetic, and optical characteristics, and also have the capability to get modified using some ligands to enrich their attraction towards the molecules at the target site, which makes them appealing for bio-imaging and drug delivery applications. One of the strong benefits of using the inorganic nanoparticles-drug conjugate is the possibility of delivering the drugs to the affected cells locally, thus reducing the side-effects like cytotoxicity, and facilitating a higher efficacy of the therapeutic drug. This review features the direct and indirect effects of such inorganic nanoparticles like gold, silver, graphene-based, hydroxyapatite, iron oxide, ZnO, and CeO2 nanoparticles in developing effective drug carrier systems. This article has remarked the peculiarities of these nanoparticle-based systems in pulmonary, ocular, wound healing, and antibacterial drug deliveries as well as in delivering drugs across Blood-Brain-Barrier (BBB) and acting as agents for cancer theranostics. Additionally, the article sheds light on the plausible modifications that can be carried out on the inorganic nanoparticles, from a researcher's perspective, which could open a new pathway.

4.
Radiat Prot Dosimetry ; 196(1-2): 95-103, 2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34514505

RESUMO

Occupational exposure data in radiation applications provide a good insight on the radiation risks to workers from occupational hazards, the safe practices adopted and in deriving methods to prevent possible radiation exposures. The analysis of occupational exposure may be used to provide regulatory guidance and more focused attention to improve the safety systems, thus improving the personnel and environment safety. In this study, occupational exposure from radiation applications during 2004-18 amounting to a total number of 1951 486 occupational dose data are collected and analysed using the statistical software package, SPSS. As recommended by the United Nations Scientific Committee on the Effects of Atomic Radiation, four critical parameters viz., annual collective effective dose, average annual effective dose, individual dose distribution ratio and the annual collective dose distribution ratio for each practice are estimated. Using the trend observed for these parameters, it is predicted that occupational exposure in diagnostic radiology in the year 2023 would increase by 80% in total number of monitored with 76% increase in average collective dose and no significant change in average annual effective dose. In the same manner, nuclear medicine would see 28% of increase in radiation workers with the increase of 24% in collective dose with no significant change in average annual effective dose. Further, the reasons and area of regulatory focus for the different practices are discussed.


Assuntos
Medicina Nuclear , Exposição Ocupacional , Exposição à Radiação , Monitoramento de Radiação , Humanos , Índia , Exposição Ocupacional/análise , Doses de Radiação
5.
J Biomater Sci Polym Ed ; 32(17): 2210-2226, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34319846

RESUMO

In this work, we prepared silver nanoparticles (AgNPs)-loaded poly(2,5-dimethoxyaniline;PDMA) nanocomposite via a simple chemical oxidative method to develop new effective biocidal and anticancer agents systems. In situ UV-vis and fluorescence spectroscopy has been used to monitor the formation of PDMA/Ag is strongly dependent on the concentration of PDMA in the present system. The FTIR and XRD studies exhibit that the rate of polymer formation and oxidation state of PDMA/Ag nanocomposite, which confirmed the AgNPs is strongly binding with the PDMA matrix. SEM and EDAX analysis revealed the presence of uniform size and the highest percentage of AgNPs (42.1%) in the PDMA/Ag nanocomposite. TEM and size distribution analysis revealed the presence of spherical AgNPs with an average diameter of 25 nm in the PDMA/Ag nanocomposite. In addition, the PDMA polymer with embedded AgNPs exhibited excellent antibacterial performance against Escherichia coli and Staphylococcus aureus. Interestingly, the prepared PDMA/Ag nanocomposite exhibited enhanced bactericidal performance compared with the PDMA polymer, presumably because of the antibacterial properties of the AgNPs substrate. The anticancer effects of combined treatment with PDMA polymer and AgNPs were evaluated using a series of cellular and biochemical assays. The findings from this study revealed that the PDMA/Ag nanocomposite treatment significantly inhibited cell viability and proliferation of the human cervical cancer cell line (HeLa). The PDMA/Ag nanocomposite exhibits better antibacterial and anticancer activities compare to pristine PDMA.


Assuntos
Antineoplásicos , Nanopartículas Metálicas , Nanocompostos , Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Humanos , Testes de Sensibilidade Microbiana , Polímeros , Prata
7.
Biotechnol Lett ; 33(12): 2391-6, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21866443

RESUMO

Glucose, maltose, and mannose as sole carbon sources, induced synthesis of glucose dehydrogenase (GDH) in three strains of Pantoea with specific activities from 0.14 to 0.6 U/mg proteins. Utilization of lactose indicated that the enzyme belongs to GDH type B isozyme. Of mutant clones, developed through radiation mutagenesis, P2-M2 utilized ribose with GDH specific activity of 0.57 U/mg protein, P4-M3 grown on glucose gave 1.5 U/mg protein and P4-M5 had high activities, when grown on galactose, maltose, and lactose. Clones P3-M2 and P2-M5 had versatile utilization of sugars and released higher amounts of P from tri-calcium phosphate and can be efficiently used for biofertilization.


Assuntos
Metabolismo dos Carboidratos/fisiologia , Melhoramento Genético/métodos , Glucose 1-Desidrogenase/química , Glucose 1-Desidrogenase/metabolismo , Pantoea/enzimologia , Pantoea/efeitos da radiação , Fosfatos/metabolismo , Metabolismo dos Carboidratos/efeitos da radiação , Carbono/metabolismo , Raios gama , Glucose/metabolismo , Maltose/metabolismo , Manose/metabolismo , Mutação/efeitos da radiação , Pantoea/classificação , Doses de Radiação , Solubilidade , Especificidade da Espécie , Especificidade por Substrato/efeitos da radiação
8.
J Endod ; 36(1): 83-6, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20003940

RESUMO

INTRODUCTION: The purpose of this study was to evaluate the antimicrobial efficacy of Triphala, green tea polyphenols (GTP), MTAD, and 5% sodium hypochlorite against E. faecalis biofilm formed on tooth substrate. METHODS: Extracted human teeth were biomechanically prepared, vertically sectioned, placed in the tissue culture wells exposing the root canal surface to E. faecalis to form a biofilm. At the end of the 3rd and 6th weeks all groups were treated for 10 minutes with the test solutions and control and were analyzed qualitatively and quantitatively. RESULTS: Qualitative assay with 3-week biofilm showed complete inhibition of bacterial growth with Triphala, MTAD and NaOCl, except GTP and saline, which showed presence of bacterial growth. In quantitative analysis, GTP- and saline-treated tooth samples have shown 1516 +/- 17.2 CFU/mL, 156.4 x 10(9) +/- 3.1 x 10(9) CFU/mL respectively. Qualitative assay with 6-week biofilm showed growth when treated with Triphala, GTP and MTAD whereas NaOCl has shown complete inhibition. All groups except NaOCl showed eight log reduction when compared to control when analyzed quantitatively. CONCLUSIONS: 5% sodium hypochlorite showed maximum antibacterial activity against E. Faecalis biofilm formed on tooth substrate. Triphala, green tea polyphenols and MTAD showed statistically significant antibacterial activity. The use of herbal alternatives as a root canal irrigant might prove to be advantageous considering the several undesirable characteristics of NaOCl.


Assuntos
Anti-Infecciosos Locais/farmacologia , Biofilmes/efeitos dos fármacos , Enterococcus faecalis/efeitos dos fármacos , Flavonoides/farmacologia , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Irrigantes do Canal Radicular/farmacologia , Chá/química , Anti-Infecciosos Locais/química , Ácido Cítrico/farmacologia , Contagem de Colônia Microbiana , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Doxiciclina/farmacologia , Enterococcus faecalis/fisiologia , Humanos , Viabilidade Microbiana/efeitos dos fármacos , Polifenóis , Polissorbatos/farmacologia , Irrigantes do Canal Radicular/química , Hipoclorito de Sódio/farmacologia
9.
Int Immunol ; 19(4): 477-86, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17314080

RESUMO

Blocking T cell co-stimulatory signals by anti-B7-1/B7-2 mAb is an attractive approach to treat autoimmune diseases. However, anti-B7-1/B7-2 mAb treatment is known to exacerbate autoimmune diseases through mechanisms not fully understood. Tumor necrosis factor alpha (TNF-alpha) and reactive oxygen species (ROS) also play important roles in determining the clinical outcome of autoimmune diseases. In this study, we demonstrate that the anti-B7-1 and the anti-B7-2 mAbs activate macrophages for higher induction of TNF-alpha and other effector responses such as bacterial cytotoxicity and production of ROS. Nuclear factor-kappaB (NF-kappaB) was found to be increased with anti-B7-1/B7-2 mAb treatment. Inhibition of NF-kappaB activity by over-expression of phosphorylation-defective I-kappaB alpha in anti-B7-1/B7-2 mAb-treated macrophages decreased TNF-alpha production. These data indicate that anti-B7-1 and anti-B7-2 mAbs can trigger innate-effector responses in macrophages by activating NF-kappaB-signaling pathway. Our results suggest that the B7 molecules are not only essential for induction of adaptive immune responses but also play roles in activation of innate immune responses.


Assuntos
Anticorpos Monoclonais/farmacologia , Antígeno B7-1/imunologia , Antígeno B7-2/imunologia , Imunidade Inata/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , NF-kappa B/metabolismo , Animais , Anticorpos Monoclonais/imunologia , Antígeno B7-1/metabolismo , Antígeno B7-2/metabolismo , Linhagem Celular , Linhagem Celular Transformada , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Meios de Cultivo Condicionados/farmacologia , Citotoxicidade Imunológica/efeitos dos fármacos , Escherichia coli/citologia , Escherichia coli/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Proteínas I-kappa B/genética , Imunidade Inata/imunologia , Fragmentos Fab das Imunoglobulinas/farmacologia , Interferon gama/farmacologia , Lipopolissacarídeos/farmacologia , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Viabilidade Microbiana/efeitos dos fármacos , Inibidor de NF-kappaB alfa , Espécies Reativas de Oxigênio/metabolismo , Transfecção , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
10.
Trop Gastroenterol ; 27(1): 11-8, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16910054

RESUMO

BACKGROUND: As modem surgery has evolved, there has been an increase in iatrogenic peritoneal adhesions. Most surgeons manage adhesions and their related complications on a regular basis. Studies in recent years have improved the understanding of the pathogenesis and impact of adhesions, which are discussed. METHODS: A systematic search of literature was performed to identify publications addressing the etiopathogenesis, clinical spectrum and effects of adhesions, using the following database: Medline (1966 to April 2005), Embase (1974 to April 2005), and the Cochrane controlled trials register. The reference lists of key publications so identified were in addition scrutinized for additional articles of relevance. RESULTS: Adhesions occur in more than three fourths of patients following laparotomy. Perironeal trauma results in a unique inflammatory process in which fibrin formation and fibrinolysis play a central role. The effects of adhesions are unpredictable but are wide ranging, causing a significant health care burden. Intestinal obstruction, infertility, problems at reoperative surgery and cumulative costs of care over many years are the key concerns. While adhesiolysis is beneficial in adhesive intestinal obstruction and infertility, its value in chronic pain is uncertain. CONCLUSION: Every violation of the peritoneum carries a potentially lifelong risk of a range of complications. Data available on the epidemiology and natural history of adhesions call for a wider acknowledgement of the problem in the planning of services and greater attention to preventive strategies.


Assuntos
Doenças Peritoneais , Procedimentos Cirúrgicos Operatórios/efeitos adversos , Dor Abdominal/etiologia , Efeitos Psicossociais da Doença , Humanos , Obstrução Intestinal/etiologia , Dor Pélvica/etiologia , Doenças Peritoneais/complicações , Doenças Peritoneais/diagnóstico , Doenças Peritoneais/etiologia , Doenças Peritoneais/fisiopatologia , Aderências Teciduais
11.
Curr Microbiol ; 53(4): 270-6, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16941245

RESUMO

This study, framed in two different phases, studied the plant-growth promotion and the induction of systemic resistance in groundnut by Methylobacterium. Seed imbibition with Methylobacterium sp. increased germination by 19.5% compared with controls. Combined inoculation of Methylobacterium sp. with Rhizobium sp. also significantly increased plant growth, nodulation, and yield attributes in groundnut compared with individual inoculation of Rhizobium sp. Methylobacterium sp. challenge-inoculated with Aspergillus niger/Sclerotium rolfsii in groundnut significantly enhanced germination percentage and seedling vigour and showed increased phenylalanine ammonia lyase (PAL), beta-1,3-glucanase, and peroxidase (PO) activities. Under pot-culture conditions, in Methylobacterium sp. seed-treated groundnut plants challenge-inoculated with A. niger/S. rolfsii through foliar sprays on day 30, the activities of enzymes PO, PAL, and beta-1,3-glucanase increased constantly from 24 to 72 hours, after which decreased activity was noted. Five isozymes of polyphenol oxidase and PO could be detected in Methylobacterium-treated plants challenged with A. niger/S. rolfsii. Induced systemic resistance activity in groundnut against rot pathogens in response to methylotrophic bacteria suggests the possibility that pink-pigmented facultative methylotrophic bacteria might be used as a means of biologic disease control.


Assuntos
Arachis/crescimento & desenvolvimento , Arachis/microbiologia , Aspergillus nidulans/patogenicidade , Methylobacterium/fisiologia , Doenças das Plantas/microbiologia , Polyporales/patogenicidade , Methylobacterium/isolamento & purificação , Reguladores de Crescimento de Plantas/análise , Rhizobium/fisiologia , Sementes/crescimento & desenvolvimento
12.
Artigo em Inglês | MEDLINE | ID: mdl-16481704

RESUMO

BACKGROUND: Vascular nevi are cutaneous anomalies of angiogenesis and vasculogenesis resulting in various different clinical presentations. AIM: The purpose of our descriptive study was to observe the various types of vascular nevi in children and their features. METHODS: A total of 4256 pediatric cases attending the dermatology OPD during the study period from August 2002 to August 2004 were screened for vascular nevi. RESULTS: Out of these, 19 children (0.44%) had vascular nevi-17 hemangiomas of infancy (HOIs) and 2 port-wine stains. The mean age of the affected children was 1.3 years (ranging from 2.5 months to 8 years). There were 13 girls and 6 boys. Seventeen (89.5%) patients had progressing lesions and two (10.5%) had non-involuting ones. A solitary lesion was seen in ten (52.6%) cases and two to five lesions were present in five (26.3%) cases. The nevi were distributed over multiple sites in seven (36.8%) cases, the head and neck in six (31.6%) cases, the chest and lower limb in two (10.5%) cases each, and the upper limbs and genitalia in one (5.3%) case each. Among the hemangiomas of infancy, 15 (88.2%) cases of superficial type and 2 (11.8%) cases of deep type were seen. The cutaneous complications included ulceration in four cases and infection in one. CONCLUSIONS: HOIs were the most common vascular nevi of childhood.


Assuntos
Hemangioma , Nevo , Mancha Vinho do Porto , Criança , Pré-Escolar , Progressão da Doença , Feminino , Neoplasias de Cabeça e Pescoço/diagnóstico , Hemangioma/diagnóstico , Hemangioma/epidemiologia , Hemangioma/patologia , Humanos , Masculino , Nevo/diagnóstico , Nevo/epidemiologia , Mancha Vinho do Porto/diagnóstico , Mancha Vinho do Porto/epidemiologia
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