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1.
R Soc Open Sci ; 11(2): 231272, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38356869

RESUMEN

As a consequence of intense investigation on possible topologies of periodic lattices, the limit of specific elastic moduli that can be achieved solely through unit cell-level geometries in artificially engineered lattice-based materials has reached a point of saturation. There exists a robust rationale to involve more elementary-level mechanics for pushing such boundaries further to develop extreme lightweight multi-functional materials with adequate stiffness. We propose a novel class of inflatable lattice materials where the global-level stiffness can be derived based on a fundamentally different mechanics compared with conventional lattices having beam-like solid members, leading to extreme specific stiffness due to the presence of air in most of the lattice volume. Furthermore, such inflatable lattices would add multi-functionality in terms of on-demand performances such as compact storing, portability and deployment along with active stiffness modulation as a function of air pressure. We have developed an efficient unit cell-based analytical approach therein to characterize the effective elastic properties including the effect of non-rigid joints. The proposed inflatable lattices would open new frontiers in engineered materials and structures that will find critical applications in a range of technologically demanding industries such as aircraft structures, defence, soft robotics, space technologies, biomedical and various other mechanical systems.

2.
Nanotechnology ; 31(14): 145705, 2020 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-31842003

RESUMEN

Carbon-based nano hetero-structures are receiving increasing attention due their ability in multi-synchronous modulation of a range of mechanical and other critically desirable properties. In this paper, the vibration characteristics of two different graphene based heterostructures, graphene-hexagonal boron nitride (hBN) and graphene-molybdenum disulfide (MoS2), are explored based on atomistic finite element approach. Such vibrational characteristics of nanostructures are of utmost importance in order to access their suitability as structural members for adoption in various nano-scale devices and systems. In the current analysis, the developed atomistic finite element model for nano-heterostructures is extensively validated first with the results available in literature considering elastic responses and natural frequencies. Thereafter a range of insightful new results are presented for the dynamic behaviour of various configurations of graphene-hBN and graphene-MoS2 heterostructures including their size, chirality and boundary dependence. The investigation of tunable vibrational properties along with simultaneous modulation of other mechanical, electronic, optical, thermal and chemical attributes of such nano-heterostructures would accelerate their application as prospective candidates for manufacturing nanosensors, electromechanical resonators, and a wide range of other devices and systems across the length-scales.

3.
Nanoscale ; 10(11): 5280-5294, 2018 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-29498731

RESUMEN

Generalized high-fidelity closed-form formulae have been developed to predict the shear modulus of hexagonal graphene-like monolayer nanostructures and nano-heterostructures based on a physically insightful analytical approach. Hexagonal nano-structural forms (top view) are common for nanomaterials with monoplanar (such as graphene and hBN) and multiplanar (such as stanene and MoS2) configurations. However, a single-layer nanomaterial may not possess a particular property adequately, or multiple desired properties simultaneously. Recently, a new trend has emerged to develop nano-heterostructures by assembling multiple monolayers of different nanostructures to achieve various tunable desired properties simultaneously. Shear modulus assumes an important role in characterizing the applicability of different two-dimensional nanomaterials and heterostructures in various nanoelectromechanical systems such as determining the resonance frequency of vibration modes involving torsion, wrinkling and rippling behavior of two-dimensional materials. We have developed mechanics-based closed-form formulae for the shear modulus of monolayer nanostructures and multi-layer nano-heterostructures. New results of shear modulus are presented for different classes of nanostructures (graphene, hBN, stanene and MoS2) and nano-heterostructures (graphene-hBN, graphene-MoS2, graphene-stanene and stanene-MoS2), which are categorized on the basis of fundamental structural configurations. The numerical values of shear modulus are compared with the results from the scientific literature (as available) and separate molecular dynamics simulations, wherein a good agreement is noticed. The proposed analytical expressions will enable the scientific community to efficiently evaluate shear modulus of a wide range of nanostructures and nanoheterostructures.

4.
Sci Rep ; 7(1): 15818, 2017 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-29150623

RESUMEN

Two-dimensional and quasi-two-dimensional materials are important nanostructures because of their exciting electronic, optical, thermal, chemical and mechanical properties. However, a single-layer nanomaterial may not possess a particular property adequately, or multiple desired properties simultaneously. Recently a new trend has emerged to develop nano-heterostructures by assembling multiple monolayers of different nanostructures to achieve various tunable desired properties simultaneously. For example, transition metal dichalcogenides such as MoS2 show promising electronic and piezoelectric properties, but their low mechanical strength is a constraint for practical applications. This barrier can be mitigated by considering graphene-MoS2 heterostructure, as graphene possesses strong mechanical properties. We have developed efficient closed-form expressions for the equivalent elastic properties of such multi-layer hexagonal nano-hetrostructures. Based on these physics-based analytical formulae, mechanical properties are investigated for different heterostructures such as graphene-MoS2, graphene-hBN, graphene-stanene and stanene-MoS2. The proposed formulae will enable efficient characterization of mechanical properties in developing a wide range of application-specific nano-heterostructures.

5.
Int J Cosmet Sci ; 39(3): 301-309, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27761899

RESUMEN

OBJECTIVE: As questions on the safety of some popular preservatives are on the rise, there is a growing interest in developing 'self-preserving' personal care products. Use of multifunctional ingredients/actives with antimicrobial properties has been explored as replacements for conventional preservatives. This study explores the use of combinations of multifunctional actives (MFA) and other cosmetic ingredients in various personal care formulations, to deliver microbiologically safe self-preserving products. Products studied in this study include face wash, gel-based leave-on skin care product and face mask. METHODS: Minimum inhibitory concentration (MIC) of several cosmetic ingredients was determined to identify multifunctional actives with antimicrobial activity. Personal care formulations made with multifunctional actives and other cosmetic ingredients were studied for preservative efficacy by challenging the product with six multiple cycles of microbial challenge. RESULTS: Formulations with combinations of multifunctional actives with antioxidant (AO) and chelators (CHL) were found to work synergistically and were highly efficacious in controlling multiple microbial challenges as observed in the preservative efficacy test (PET) studies. The effective combinations were able to withstand up to six multiple microbial challenges without product degradation. The preservative efficacy profile was similar to control formula containing preservatives. CONCLUSION: Self-preserving personal care/cosmetic products can be developed which are as efficacious as preserved products by a prudent selection of multifunctional actives, antioxidants and chelators as a part of the formulation.


Asunto(s)
Cosméticos , Conservadores Farmacéuticos/farmacología , Bacterias/efectos de los fármacos , Hongos/efectos de los fármacos , Pruebas de Sensibilidad Microbiana
6.
Mymensingh Med J ; 24(4): 838-44, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26620028

RESUMEN

This cross-sectional study was done to find and investigate the utilization pattern of iron chelating agents among 73 transfusion-dependent thalassaemia major patients with continuous enrolment for at least 1 year in a day care treatment centre run by The Thalassaemia Society of India, Kolkata from November 2014 to January 2015. Transfusion dependent thalassaemia major patients above the age of 2 years managed by various haematologists and Thalassaemia specialists were studied. The administration of iron chelators namely Desferrioxamine (DFO), Deferiprone (DFP) and Deferasirox (DFX) were evaluated. Forty seven (64%) of the thalassaemics had serum ferritin level below 2500 ng/dl, of whom 20(27%) patients have ferritin level below 1000ng/dl. A number of 55(75%) of 73 patients who were treated with a single chelating agent consisted 50 patients only on DFX. Exact 8(67%) patients were on DFO+DFP and 4(33%) are treated with DFX+DFP. The mean age was 19 and mean serum ferritin level was 2280 ng/dl among the thalassaemia major patients. DFX was used 68% of patients as monotherapy and 5% patients in combination therapy with DFP. DFX in the dose of 30-40 mg/kg/day was prescribed in 52% of patients. Mean dose of 15 mg/kg/day of DFX was been administered in combination with DFP (75 mg/kg/day) in 5% patients. DFO+DFP were preferred by 8 patients, out of which 6 were aged above 25. Cost of monotherapy is twice that of combination therapy. These data demonstrates the ferritin status and present scenario of utilization of chelating agents among thalassaemia major patients on repeated transfusions. The dosing of new drug, Deferasirox and the cost analysis of various chelating regimen has also been dealt. Individualization rather than rationalization of chelation therapy should be focussed upon in managing iron overload in thalassaemia.


Asunto(s)
Transfusión Sanguínea , Quelantes del Hierro/uso terapéutico , Talasemia beta/terapia , Adolescente , Adulto , Estudios Transversales , Femenino , Ferritinas/sangre , Humanos , Masculino , Reacción a la Transfusión , Adulto Joven , Talasemia beta/sangre
7.
J Dairy Sci ; 95(6): 2935-45, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22612931

RESUMEN

We assessed the suitability of 9 internal control genes (ICG) in milk somatic cells of lactating cows to find suitable reference genes for use in quantitative PCR (qPCR). Eighteen multiparous lactating Sahiwal cows were used, 6 in each of 3 lactation stages: early (25 ± 5 d in milk), mid (160 ± 15 d in milk), and late (275 ± 25 d in milk) lactation. Nine candidate reference genes [glyceraldehyde 3-phosphate dehydrogenase (GAPDH), protein phosphatase 1 regulatory subunit 11 (PPP1R11), ß-actin (ACTB), ß-2 microglobulin (B2M), 40S ribosomal protein S15a (RPS15A), ubiquitously expressed transcript (UXT), mitochondrial GTPase 1 (MTG1), 18S rRNA (RN18S1), and ubiquitin (UBC)] were evaluated. Three genes, ß-casein (CSN2), lactoferrin (LTF), and cathelicidin (CAMP) were chosen as target genes. Very high amplification was observed in 7 ICG and very low level amplification was observed in 2 ICG (UXT and MTG1). Thus, UXT and MTG1 were excluded from further analysis. The qPCR data were analyzed by 2 software packages, geNorm and NormFinder, to determine suitable reference genes, based on their stability and expression. Overall, PPP1R11, ACTB, UBC, and GAPDH were stably expressed among all candidate reference genes. Therefore, these genes could be used as ICG for normalization of qPCR data in milk somatic cells through lactation.


Asunto(s)
Genes/genética , Lactancia/genética , Leche/citología , Carácter Cuantitativo Heredable , Animales , Bovinos/genética , ADN Complementario/genética , Femenino , Expresión Génica/genética , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria
8.
J Appl Microbiol ; 111(5): 1224-34, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21895896

RESUMEN

AIM: The aim of this study was to investigate the role of quorum sensing in Bacillus anthracis growth and toxin production. METHODS AND RESULTS: A microwell plate culture method was developed to simulate the normal UK-licensed anthrax vaccine production run. Once established, sterile supernatant additions from a previous B. anthracis culture were made, and reductions in lag phase and early stimulation of the anthrax toxin component protective antigen (PA) were monitored using ELISA. The addition of the quorum-sensing inhibitor, fur-1, prolonged the lag phase and impeded PA production. Spin filters of various sizes were used to identify the molecular weight fraction of the sterile supernatant responsible for the autoinducer effect. A weight fraction between 5 and 10 kDa was responsible for the autoinducer effect; however, further identification using mass spectroscopy proved inconclusive. CONCLUSIONS: Quorum sensing mediated by the autoinducer two molecule plays a significant role in both B. anthracis growth and toxin production. SIGNIFICANCE AND IMPACT OF THE STUDY: While genomic analysis has eluded to the importance of LuxS and quorum sensing in anthrax, this is the first analysis using a production strain of B. anthracis and a quorum-sensing inhibitor to monitor the effect on growth and toxin production. This gives insights into anthrax pathogenicity and vaccine manufacture.


Asunto(s)
Antígenos Bacterianos/biosíntesis , Bacillus anthracis/crecimiento & desarrollo , Toxinas Bacterianas/biosíntesis , Fermentación , Percepción de Quorum , Vacunas contra el Carbunco/biosíntesis , Bacillus anthracis/efectos de los fármacos , Bacillus anthracis/metabolismo , Ensayo de Inmunoadsorción Enzimática , Furanos/farmacología
9.
Pharmacognosy Res ; 3(2): 143-5, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21772760

RESUMEN

Bioassay-guided isolation of methanolic extract of the leaves of Origanum vulgare Linn., yielded two protocatechuic acid ester derivatives, origanol A (1) and origanol B (2) along with ursolic acid (3), oleanolic acid (4), ß-sitosterol (5), and triacontanol (6). Structures of the compound were established based on physical and spectral data (UV, IR, (1)H and (13)C NMR and mass). Origanol A (1) showed significant mushroom tyrosinase inhibition activity.

10.
Colorectal Dis ; 12 Suppl 2: 30-6, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20618365

RESUMEN

AIM: Preoperative radiotherapy has been shown to improve local control in advanced rectal carcinoma compared with surgery alone. Several large randomized trials have confirmed that chemoradiotherapy (CRT) is better than radiotherapy alone. This pilot study was designed to increase the radiation dose using high-dose rate (HDR) brachytherapy boost following preoperative CRT to evaluate whether this strategy improves the outcome of surgery without increase in toxicity. METHOD: Since October 2004, we have used the new rectal HDR applicator for brachytherapy boost in 68 patients following CRT. The patients had CT and MRI Scans as part of staging. All had locally advanced disease either bulky low T2 or T3 with threatened circumferential resection margin and multiple suspicious lymph nodes. They were offered preoperative CRT either by 5-FU infusion 1 g/m(2) day 1-4 (week 1 + 5) or by oral capecitabine 825 mg/m(2) Monday-Friday for 5 weeks together with CT planned external beam RT 45Gy in 25 fractions over 5 weeks (CRT). Those downstage on repeat MRI scan were offered additional HDR Boost 10Gy directly to the tumour followed by surgery 6-8 weeks later [group A]. Four patients proceeded directly to surgery but because of involved resection margin had a HDR brachytherapy boost as postoperative treatment [group B]. Thirty patients were not planned for immediate surgery after CRT and brachytherapy boost, as they were either elderly or considered high risk for anaesthesia [group C]. RESULTS: There were 34 patients (median age 67 (range 39-81) years in group A, including 24 men). The PS was 0-1. The clinical stage at presentation was cT2 in five, cT3 in 23 and T4 in six patients and cN0 in 2, cN1 in 21 and N2 in 11. Thirty-three patients had CRT, and one had radiotherapy alone. All patients completed treatment without interruption. Twenty-nine patients had surgery following CRT and brachytherapy boost including anterior resection in 10 patients, Abdominoperineal excision (APR) in 18 and Hartmann's resection in one. Five patients did not have the intended surgery. Twenty-four (83%) patients had an RO resection compared with 63% having conventional preoperative CRT using bolus 5FU regimes. Pathological complete remission (pCR) was achieved in 9 (31%) compared with 12% patients having conventional CRT. There was no increase in G 3-4 toxicity from RT and no delay in wound healing or increase in anastomotic leakage. One of the four patients in group B developed local recurrence. The thirty patients in group C who had modified radical CRT followed by brachytherapy boost as a definitive treatment will be reported in a further communication. CONCLUSION: Increasing the dose of radiation by HDR brachytherapy boost appears to improve the RO resection and pCR rates compared with conventional CRT. The follow up is too short to judge its effect on disease-free survival. This study will be extended to compare this strategy in a randomized phase III trial with conventional CRT in patients who are not fit for more intensive CRT (HERCULES).


Asunto(s)
Braquiterapia/métodos , Neoplasias del Recto/radioterapia , Adulto , Anciano , Anciano de 80 o más Años , Terapia Combinada , Relación Dosis-Respuesta en la Radiación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante , Recurrencia Local de Neoplasia/prevención & control , Estadificación de Neoplasias , Proyectos Piloto , Neoplasias del Recto/tratamiento farmacológico , Neoplasias del Recto/cirugía , Análisis de Supervivencia
11.
Indian J Dermatol ; 55(2): 130-4, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20606879

RESUMEN

The article discuss in detail about the prevalence, pathophysiology, clinical manifestations of dandruff including the etio-pathology. The article also discusses in detail about various treatment methods available for dandruff. The status of dandruff being amphibious - a disease/disorder, and relatively less medical intervention is sought after for the treatment, dandruff is the most commercially exploited skin and scalp disorder/disease by personal care industries.

12.
Indian J Clin Biochem ; 18(2): 131-5, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23105404

RESUMEN

Mucoproteins are normal and essential constituents of different types of cells, tissues, and organs in our body. Interestingly, an increase in the serum mucoprotein has been described in several malignant disorders in various studies. To study this in the cases of hepatocellular carcinoma thirty five patients suffering from histologically or cytologically confirmed hepatocellular carcinoma were tested for serum mucoprotein in the Department of Biochemistry and the Department of Pathology of North Bengal Medical College for a period of one and a half years against matched healthy controls. The serum mucoprotein was found to be increased significantly in the cases suffering from hepatocellular carcinoma (p<0.001). So, the present study suggests a strong correlation between the mucoprotein level and carcinomatous changes in the hepatocellular tissues.

13.
J Intellect Disabil Res ; 46 Suppl 1: 6-20, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-12061335

RESUMEN

The investigation of the relationship between criminal offending and the presence of an intellectual disability (ID) is problematic for two main reasons. First, because of problems associated with the definition of 'ID' and secondly, because much criminal offending goes undetected or unreported, and studies can only investigate those already involved with the criminal justice process. Studies using IQ as a continuous variable indicate that significantly below-average intellectual ability is an independent predictor of future offending. Whilst people with ID may be over-represented in parts of the criminal justice system, given the intellectual and other psychosocial disadvantages which they experience, the level of offending behaviour in this particularly vulnerable group is strikingly low. The present authors propose that two broad groups of people can be identified. The first, broader, group is one of people for whom social disadvantage and mental ill health (particularly substance abuse), coupled with a significant intellectual impairment, are the main characteristics. Secondly, there is a smaller group of people, usually already known to ID services as service users, but for whom the process whereby what might have been conceptualized as 'challenging behaviour' becomes 'offending' is far from clear. The distinction the present authors make between challenging behaviour and offending is important for understanding how 'difficult' behaviour becomes identified as 'antisocial/criminal behaviour'. They argue that research needs to move from prevalence and descriptive studies to investigating the processes which determine movement in and out the criminal justice system. The present political emphasis on public protection and proposals for significantly broader mental health legislation raise the danger of a re-expansion of institutional models of care, rather than the development of multi-agency support networks. The present paper underscores a note of caution, particularly where choices have to be made between expanding institutional models on the one hand and providing more integrated services on the other. Over and above policy decisions, these are social and political choices.


Asunto(s)
Crimen/estadística & datos numéricos , Discapacidad Intelectual/epidemiología , Evaluación de Necesidades/estadística & datos numéricos , Comorbilidad , Crimen/legislación & jurisprudencia , Crimen/prevención & control , Estudios Transversales , Conducta Peligrosa , Femenino , Humanos , Masculino , Carencia Psicosocial , Medición de Riesgo , Reino Unido/epidemiología
15.
Int J Radiat Oncol Biol Phys ; 48(4): 1127-37, 2000 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-11072172

RESUMEN

PURPOSE: The purpose of this study was to investigate the efficacy of 2-methoxyestradiol as an antitumor and radiosensitizing agent for the treatment of human malignancy. METHODS AND MATERIALS: Two cancer cell lines with wild-type p53 status were exposed first to irradiation and then to an oral formulation of the nontoxic metabolite 2-methoxyestradiol (2ME) to stabilize p53 levels. RESULTS: Cell growth was inhibited via G1 growth and apoptosis. Subsequent in vitro growth and Tunel assays indicated that this combination was superior to radiation alone at inducing p53 protein accumulation, stabilizing p53 protein levels, and substantially reducing long-term tumor cell growth (approximately 80%) and colony formation (approximately 95%) in vitro, and inducing apoptosis. However, harboring mutated p53, H322 cell line, was relatively insensitive to such a treatment regimen. Western blot analysis revealed that growth inhibition was associated with increased levels of p53 and p21 protein accumulation. Experiments with subcutaneous tumor in a nu/nu mouse showed the combination treatment to be superior to radiation alone at reducing tumor growth ( approximately 50% reduction as compared to radiation alone) in vivo. CONCLUSION: Thus, our studies confirmed a unique strategy whereby oral administration of a nontoxic estrogen metabolite, 2ME, significantly enhanced the radiation effect on a subcutaneous tumor without any toxicity and suggesting that this strategy may be clinically useful as an adjuvant therapy.


Asunto(s)
Antineoplásicos/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Estradiol/uso terapéutico , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/radioterapia , Proteínas de Neoplasias/metabolismo , Fármacos Sensibilizantes a Radiaciones/uso terapéutico , Proteína p53 Supresora de Tumor/metabolismo , 2-Metoxiestradiol , Administración Oral , Apoptosis , División Celular/efectos de los fármacos , División Celular/efectos de la radiación , Terapia Combinada , Inhibidor p21 de las Quinasas Dependientes de la Ciclina , Ciclinas/metabolismo , Estradiol/análogos & derivados , Humanos , Proteínas de Neoplasias/genética , Radiobiología , Células Tumorales Cultivadas/efectos de los fármacos , Células Tumorales Cultivadas/efectos de la radiación , Ensayo de Tumor de Célula Madre , Proteína p53 Supresora de Tumor/genética
16.
Mol Cell Biol ; 20(24): 9391-8, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11094089

RESUMEN

To investigate the effect of mutations in the p53 C-terminal domain on MDM2-mediated degradation, we introduced single and multiple point mutations into a human p53 cDNA at four putative acetylation sites (amino acid residues 372, 373, 381, and 382). Substitution of all four lysine residues by alanines (the A4 mutant) and single lysine-to-alanine substitutions were functional in sequence-specific DNA binding and transactivation; however, the A4 mutant protein was resistant to MDM2-mediated degradation, whereas the single lysine substitutions were not. Although the A4 mutant protein and the single lysine substitutions both bound MDM2 reasonably well, the single lysine substitutions underwent normal MDM2-dependent ubiquitination, whereas the A4 protein was inefficiently ubiquitinated. In addition, the A4 mutant protein was found in the cytoplasm as well as in the nucleus of a subpopulation of cells, unlike wild-type p53, which is mostly nuclear. The partially cytoplasmic distribution of A4 mutant protein was not due to a defect in nuclear import because inhibition of nuclear export by leptomycin B resulted in nuclear accumulation of the protein. Taken together, the data suggest that mutations in the putative acetylation sites of the p53 C-terminal domain interfere with ubiquitination, thereby regulating p53 degradation.


Asunto(s)
Proteínas Activadoras de GTPasa/metabolismo , Genes p53/genética , Proteínas Nucleares/metabolismo , Estructura Terciaria de Proteína , Proteínas Proto-Oncogénicas/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Acetilación , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Carcinoma de Pulmón de Células no Pequeñas , Fraccionamiento Celular , Ecdisona/análogos & derivados , Ecdisona/farmacología , Ácidos Grasos Insaturados/farmacología , Regulación de la Expresión Génica , Genes Reporteros , Humanos , Immunoblotting , Inmunohistoquímica , Neoplasias Pulmonares , Proteínas Nucleares/genética , Plásmidos/genética , Plásmidos/metabolismo , Mutación Puntual , Pruebas de Precipitina , Proteínas Proto-Oncogénicas c-mdm2 , Activación Transcripcional , Transfección , Células Tumorales Cultivadas , Proteína p53 Supresora de Tumor/química , Proteína p53 Supresora de Tumor/genética
17.
Cancer Gene Ther ; 7(4): 530-6, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10811470

RESUMEN

The immune responses of 10 patients with advanced non-small cell lung cancer receiving monthly intratumoral injections of a recombinant adenovirus containing human wild-type p53 (Ad-p53) to adenovirus and transgene antigens were studied. The predominate cellular and humoral immune responses as measured by lymphocyte proliferation and neutralizing antibody (Ab) formation were to adenovirus serotype 5 vector antigens, with increased responses in posttreatment samples. Consistent alterations in posttreatment cellular and humoral immune responses to p53 epitopes were not observed, and cytotoxic Abs to human lung cancer cells were not generated. Patients in this study had evidence of an antitumoral effect of this treatment with prolonged tumor stability or regression; however, neither Abs to p53 protein nor increased lymphocyte proliferative responses to wild-type or mutant p53 peptides have been consistently detected.


Asunto(s)
Adenoviridae/inmunología , Carcinoma de Pulmón de Células no Pequeñas/terapia , Terapia Genética/métodos , Neoplasias Pulmonares/terapia , Proteína p53 Supresora de Tumor/inmunología , Adenoviridae/genética , Anciano , Secuencia de Aminoácidos , Formación de Anticuerpos , Carcinoma de Pulmón de Células no Pequeñas/inmunología , Citotoxicidad Inmunológica , Femenino , Técnicas de Transferencia de Gen , Vectores Genéticos/inmunología , Humanos , Inmunidad Celular , Neoplasias Pulmonares/inmunología , Activación de Linfocitos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Fragmentos de Péptidos/química , Fragmentos de Péptidos/inmunología , Proteína p53 Supresora de Tumor/química , Proteína p53 Supresora de Tumor/genética
18.
J Nat Prod ; 62(11): 1562-4, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10579874

RESUMEN

Methylsulfomycin I (1) is a new cyclic peptide antibiotic isolated from the fermentation broth of a Streptomyces sp. HIL Y-9420704. Its structure was elucidated by NMR and GC-MS. The in vitro activity (MIC) against a wide range of Gram-positive bacteria, including methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-, and teicoplanin-resistant strains, is described.


Asunto(s)
Antibacterianos/aislamiento & purificación , Streptomyces/metabolismo , Animales , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Fermentación , Ratones , Pruebas de Sensibilidad Microbiana , Conformación Molecular , Péptidos Cíclicos/aislamiento & purificación , Péptidos Cíclicos/farmacología , Solventes , Espectrometría de Masa Bombardeada por Átomos Veloces , Espectrofotometría Infrarroja , Espectrofotometría Ultravioleta
19.
J Nat Prod ; 62(6): 889-90, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10395510

RESUMEN

A new macrocyclic lactone antibiotic mathemycin B (1) was isolated from the fermentation broth of an Actinomycete sp. culture Y-8620959. The structure of 1 was elucidated by high-resolution MS and interpretation of 2D NMR results. Mathemycin B is active against a variety of phytopathogenic organisms.


Asunto(s)
Actinomycetales/química , Antibacterianos/aislamiento & purificación , Antifúngicos/aislamiento & purificación , Macrólidos , Antibacterianos/farmacología , Antifúngicos/farmacología , Fermentación , Hongos/efectos de los fármacos , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Pruebas de Sensibilidad Microbiana
20.
Clin Cancer Res ; 5(3): 493-9, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10100698

RESUMEN

We examined the effect of 2-methoxyestradiol (2-ME) on the growth and tumorigenesis of human pancreatic cancer cells. 2-ME inhibited the growth of these cell lines (50-90%) in a dose- and time-dependent fashion, and terminal deoxynucleotidyl transferase staining showed that it induced apoptotic cell death. Flow cytometric analysis indicated that 2-ME-sensitive cells showed a prolonged S phase after 48 h of treatment. We used a mouse model for in vivo studies of lung metastasis and injected MIA PaCa-2 cells into the tail veins of nu/nu mice; lung colonies were formed. Mice given oral 2-ME showed 60% inhibition in the number of lung colonies compared with control, untreated animals. These results suggest that 2-ME may have clinical application for the treatment of pancreatic cancer.


Asunto(s)
Antineoplásicos/uso terapéutico , Estradiol/análogos & derivados , Neoplasias Pancreáticas/tratamiento farmacológico , 2-Metoxiestradiol , Animales , Apoptosis , División Celular/efectos de los fármacos , Fragmentación del ADN/efectos de los fármacos , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Estradiol/uso terapéutico , Humanos , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/prevención & control , Neoplasias Pulmonares/secundario , Ratones , Ratones Desnudos , Metástasis de la Neoplasia , Trasplante de Neoplasias , Neoplasias Pancreáticas/patología , Células Tumorales Cultivadas
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