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1.
Proc Natl Acad Sci U S A ; 112(12): E1433-42, 2015 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-25713383

RESUMEN

Extracellular vesicles (EVs), specifically exosomes and microvesicles (MVs), are presumed to play key roles in cell-cell communication via transfer of biomolecules between cells. The biogenesis of these two types of EVs differs as they originate from either the endosomal (exosomes) or plasma (MVs) membranes. To elucidate the primary means through which EVs mediate intercellular communication, we characterized their ability to encapsulate and deliver different types of macromolecules from transiently transfected cells. Both EV types encapsulated reporter proteins and mRNA but only MVs transferred the reporter function to recipient cells. De novo reporter protein expression in recipient cells resulted only from plasmid DNA (pDNA) after delivery via MVs. Reporter mRNA was delivered to recipient cells by both EV types, but was rapidly degraded without being translated. MVs also mediated delivery of functional pDNA encoding Cre recombinase in vivo to tissues in transgenic Cre-lox reporter mice. Within the parameters of this study, MVs delivered functional pDNA, but not RNA, whereas exosomes from the same source did not deliver functional nucleic acids. These results have significant implications for understanding the role of EVs in cellular communication and for development of EVs as delivery tools. Moreover, studies using EVs from transiently transfected cells may be confounded by a predominance of pDNA transfer.


Asunto(s)
ADN/química , Exosomas/química , Animales , Apoptosis , Transporte Biológico/genética , Comunicación Celular , Membrana Celular/metabolismo , Citometría de Flujo , Silenciador del Gen , Genes Reporteros/genética , Células HEK293 , Humanos , Integrasas/metabolismo , Lípidos/química , Sustancias Macromoleculares/química , Ratones , Ratones Transgénicos , Microscopía de Fuerza Atómica , Microscopía Confocal , Microscopía Fluorescente , Fosfatidilserinas/química , Plásmidos , Polietilenglicoles/química , ARN Mensajero/metabolismo , Tetraspanina 30/química
2.
BMC Cancer ; 16: 524, 2016 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-27457630

RESUMEN

BACKGROUND: Success of cancer prodrugs relying on a foreign gene requires specific delivery of the gene to the cancer, and improvements such as higher level gene transfer and expression. Attaining these objectives will be facilitated in preclinical studies using our newly discovered CNOB-GDEPT, consisting of the produrg: 6-chloro-9-nitro-5-oxo-5H-benzo-(a)-phenoxazine (CNOB) and its activating enzyme ChrR6, which generates the cytotoxic product 9-amino-6-chloro-5H-benzo[a]phenoxazine-5-one (MCHB). MCHB is fluorescent and can be noninvasively imaged in mice, and here we investigated whether MCHB fluorescence quantitatively reflects its concentration, as this would enhance its reporter value in further development of the CNOB-GDEPT therapeutic regimen. PK parameters were estimated and used to predict more effective CNOB administration schedules. METHODS: CNOB (3.3 mg/kg) was injected iv in mice implanted with humanized ChrR6 (HChrR6)-expressing 4T1 tumors. Fluorescence was imaged in live mice using IVIS Spectrum, and quantified by Living Image 3.2 software. MCHB and CNOB were quantified also by LC/MS/MS analysis. We used non-compartmental model to estimate PK parameters. Phoenix WinNonlin software was used for simulations to predict a more effective CNOB dosage regimen. RESULTS: CNOB administration significantly prolonged mice survival. MCHB fluorescence quantitatively reflected its exposure levels to the tumor and the plasma, as verified by LC/MS/MS analysis at various time points, including at a low concentration of 2 ng/g tumor. The LC/MS/MS data were used to estimate peak plasma concentrations, exposure (AUC0-24), volume of distribution, clearance and half-life in plasma and the tumor. Simulations suggested that the CNOB-GDEPT can be a successful therapy without large increases in the prodrug dosage. CONCLUSION: MCHB fluorescence quantifies this drug, and CNOB can be effective at relatively low doses. MCHB fluorescence characteristics will expedite further development of CNOB-GDEPT by, for example, facilitating specific gene delivery to the tumor, its prolonged expression, as well as other attributes necessary for successful gene-delivered enzyme prodrug therapy.


Asunto(s)
Antineoplásicos/farmacocinética , Oxazinas/farmacocinética , Profármacos/farmacocinética , Animales , Antineoplásicos/administración & dosificación , Línea Celular Tumoral , Esquema de Medicación , Humanos , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Imagen Óptica , Oxazinas/administración & dosificación , Profármacos/administración & dosificación
3.
Breast Cancer Res ; 16(2): R36, 2014 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-24708766

RESUMEN

INTRODUCTION: Triple-negative breast cancer (TNBC) is aggressive and lacks targeted therapies. Phosphatidylinositide 3-kinase (PI3K)/mammalian target of rapamycin (mTOR) pathways are frequently activated in TNBC patient tumors at the genome, gene expression and protein levels, and mTOR inhibitors have been shown to inhibit growth in TNBC cell lines. We describe a panel of patient-derived xenografts representing multiple TNBC subtypes and use them to test preclinical drug efficacy of two mTOR inhibitors, sirolimus (rapamycin) and temsirolimus (CCI-779). METHODS: We generated a panel of seven patient-derived orthotopic xenografts from six primary TNBC tumors and one metastasis. Patient tumors and corresponding xenografts were compared by histology, immunohistochemistry, array comparative genomic hybridization (aCGH) and phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit alpha (PIK3CA) sequencing; TNBC subtypes were determined. Using a previously published logistic regression approach, we generated a rapamycin response signature from Connectivity Map gene expression data and used it to predict rapamycin sensitivity in 1,401 human breast cancers of different intrinsic subtypes, prompting in vivo testing of mTOR inhibitors and doxorubicin in our TNBC xenografts. RESULTS: Patient-derived xenografts recapitulated histology, biomarker expression and global genomic features of patient tumors. Two primary tumors had PIK3CA coding mutations, and five of six primary tumors showed flanking intron single nucleotide polymorphisms (SNPs) with conservation of sequence variations between primary tumors and xenografts, even on subsequent xenograft passages. Gene expression profiling showed that our models represent at least four of six TNBC subtypes. The rapamycin response signature predicted sensitivity for 94% of basal-like breast cancers in a large dataset. Drug testing of mTOR inhibitors in our xenografts showed 77 to 99% growth inhibition, significantly more than doxorubicin; protein phosphorylation studies indicated constitutive activation of the mTOR pathway that decreased with treatment. However, no tumor was completely eradicated. CONCLUSIONS: A panel of patient-derived xenograft models covering a spectrum of TNBC subtypes was generated that histologically and genomically matched original patient tumors. Consistent with in silico predictions, mTOR inhibitor testing in our TNBC xenografts showed significant tumor growth inhibition in all, suggesting that mTOR inhibitors can be effective in TNBC, but will require use with additional therapies, warranting investigation of optimal drug combinations.


Asunto(s)
Antineoplásicos/uso terapéutico , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Ensayos Antitumor por Modelo de Xenoinjerto/métodos , Animales , Western Blotting , Línea Celular Tumoral , Fosfatidilinositol 3-Quinasa Clase I , Hibridación Genómica Comparativa , Análisis Mutacional de ADN , Doxorrubicina/uso terapéutico , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Inmunohistoquímica , Células MCF-7 , Ratones , Mutación , Análisis de Secuencia por Matrices de Oligonucleótidos , Fosfatidilinositol 3-Quinasas/genética , Fosforilación/efectos de los fármacos , Proteínas Quinasas S6 Ribosómicas 70-kDa/genética , Proteínas Quinasas S6 Ribosómicas 70-kDa/metabolismo , Sirolimus/análogos & derivados , Sirolimus/uso terapéutico , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismo , Transcriptoma/efectos de los fármacos , Neoplasias de la Mama Triple Negativas/genética , Neoplasias de la Mama Triple Negativas/metabolismo
4.
Antimicrob Agents Chemother ; 58(10): 5964-75, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25070093

RESUMEN

Stationary-phase bacteria are important in disease. The σ(s)-regulated general stress response helps them become resistant to disinfectants, but the role of σ(s) in bacterial antibiotic resistance has not been elucidated. Loss of σ(s) rendered stationary-phase Escherichia coli more sensitive to the bactericidal antibiotic gentamicin (Gm), and proteomic analysis suggested involvement of a weakened antioxidant defense. Use of the psfiA genetic reporter, 3'-(p-hydroxyphenyl) fluorescein (HPF) dye, and Amplex Red showed that Gm generated more reactive oxygen species (ROS) in the mutant. HPF measurements can be distorted by cell elongation, but Gm did not affect stationary-phase cell dimensions. Coadministration of the antioxidant N-acetyl cysteine (NAC) decreased drug lethality particularly in the mutant, as did Gm treatment under anaerobic conditions that prevent ROS formation. Greater oxidative stress, due to insufficient quenching of endogenous ROS and/or respiration-linked electron leakage, therefore contributed to the greater sensitivity of the mutant; infection by a uropathogenic strain in mice showed this to be the case also in vivo. Disruption of antioxidant defense by eliminating the quencher proteins, SodA/SodB and KatE/SodA, or the pentose phosphate pathway proteins, Zwf/Gnd and TalA, which provide NADPH for ROS decomposition, also generated greater oxidative stress and killing by Gm. Thus, besides its established mode of action, Gm also kills stationary-phase bacteria by generating oxidative stress, and targeting the antioxidant defense of E. coli can enhance its efficacy. Relevant aspects of the current controversy on the role of ROS in killing by bactericidal drugs of exponential-phase bacteria, which represent a different physiological state, are discussed.


Asunto(s)
Antibacterianos/farmacología , Antioxidantes/metabolismo , Escherichia coli/efectos de los fármacos , Escherichia coli/metabolismo , Gentamicinas/farmacología , Factor sigma/metabolismo , Animales , Femenino , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Ratones
5.
Appl Environ Microbiol ; 80(7): 2270-8, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24487539

RESUMEN

The aim of this study is to provide understanding of microgravity effects on important food-borne bacteria, Escherichia coli O157:H7 ATCC 35150, ATCC 43889, and ATCC 43895, cultured in nutrient-rich or minimal medium. Physiological characteristics, such as growth (measured by optical density and plating), cell morphology, and pH, were monitored under low-shear modeled microgravity (LSMMG; space conditions) and normal gravity (NG; Earth conditions). In nutrient-rich medium, all strains except ATCC 35150 showed significantly higher optical density after 6 h of culture under LSMMG conditions than under NG conditions (P < 0.05). LSMMG-cultured cells were approximately 1.8 times larger than NG-cultured cells at 24 h; therefore, it was assumed that the increase in optical density was due to the size of individual cells rather than an increase in the cell population. The higher pH of the NG cultures relative to that of the LSMMG cultures suggests that nitrogen metabolism was slower in the latter. After 24 h of culturing in minimal media, LSMMG-cultured cells had an optical density 1.3 times higher than that of NG-cultured cells; thus, the higher optical density in the LSMMG cultures may be due to an increase in both cell size and number. Since bacteria actively grew under LSMMG conditions in minimal medium despite the lower pH, it is of some concern that LSMMG-cultured E. coli O157:H7 may be able to adapt well to acidic environments. These changes may be caused by changes in nutrient metabolism under LSMMG conditions, although this needs to be demonstrated in future studies.


Asunto(s)
Escherichia coli O157/fisiología , Ingravidez , Medios de Cultivo/química , Escherichia coli O157/citología , Escherichia coli O157/crecimiento & desarrollo , Escherichia coli O157/metabolismo , Concentración de Iones de Hidrógeno , Espectrofotometría
6.
J Colloid Interface Sci ; 676: 657-669, 2024 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-39053413

RESUMEN

The presence of emerging organic micropollutants (OMPs) in drinking and potable waters is a matter of great concern due to the health hazards associated with these. In this work, we present the preparation and application of a thin-film nanocomposite (TFN) membrane containing functionalized graphene oxide to effectively remove low-molecular-weight OMPs from water. Graphene oxide was functionalized with amino silane to enhance its cross-linking capability during the formation of the polyamide active layer via interfacial polymerization of diethylene triamine and trimesoyl chloride. The TEM analysis showed that amino silane functionalized GO had 2-3 layered sheets, while non-functionalized graphene oxide appeared multilayered or stacked. XPS analysis confirmed the successful functionalization of GO. Characterization of the membranes with advanced techniques confirmed the successful incorporation of the GO and its functionalization: spectra from Fourier Transform Infra Red spectroscopy had the characteristic peaks of GO and NH groups; scanning Electron Microscopy (SEM) images showed a continuous presence of GO nanosheets. Contact angle measurements showed the TFN membranes to be more hydrophilic than their thin film composite (TFC) counterparts. Incorporating functionalized oxide nanosheets in the active polyamide layer produced additional water permeation channels, resulting in an improvement of ∼25 % in permeate flux compared to the pristine TFC and the TFN membrane with non-functionalized GO. The removal efficiencies of four OMPs commonly found in natural waters: Amitriptylene HCl (ATT HCl) and Bisphenol-A (BPA), Acetaminophen (ACT), and Caffeine (CFN) were determined for the synthesized membranes. The TFN membrane with functionalized GO outperformed its TFC counterpart with ∼100 % removal for BPA, ∼ 90 % for CFN and ATT HCl, and ∼80 % removal for the low molecular weight ACT. The high-efficiency rejection of OMPs was attributed to the synergistic effects of size exclusion as well as the reduced specific interactions between the functional groups.

7.
Braz J Biol ; 84: e280796, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39140501

RESUMEN

Marine organisms produce a variety of compounds with pharmacological activities. In order to better comprehend the medicinal value of five particular seaweed orders Ulvales (Ulva intestinalis), Bryopsidales (Codium decorticatum), Ectocarpales (Iyengaria stellata), Dictyotales (Spatoglossum aspermum) and Gigartinales (Hypnea musciformis), a bioactive analysis including the screening of phytochemical components, antioxidant and antimicrobial activities was the aim of the investigation. The species include U. intestinalis was collected from Sandspit, while C. decorticatum, I. stellata, S. aspermum, and H. musciformis were gathered from Buleji. These species evaluated for their ability to inhibit human infectious gram positive pathogens Staphylococcus aureus, Staphylococcus epidermidis as well as gram negative bacteria Escherichia coli. Additionally vegetable pathogen Fusarium oxysporum, and fruit pathogens (Aspergillus niger and Aspergillus flavus) were evaluated to determine the zone of inhibition. Two organic solvents, ethanol and methanol, were used to prepare seaweed extract. The disc diffusion method was utilized to quantify the zone of inhibition and the DPPH method was employed to measure the antioxidant activity. The study unveiled various phyto-constituents in the tested seaweeds, with flavonoids, tannins, and proteins found in all selected species, while saponins, terpenoids, and carbohydrates were absent in I. stellata and S. aspermum. Notably, ethanolic extracts of I. stellata and S. aspermum demonstrated superior higher antioxidant activity, with increasing percentages of inhibition from 1 to 6 mg/ml. Furthermore, the findings indicated that the ethanolic extract of U. intestinalis displayed the highest resistance against F. oxysporum and A. flavous among other seaweeds. Meanwhile, the ethanolic extract of C. decorticatum exhibited the highest resistance against A. Niger. Additionally, the ethanolic extract of I. stellata and H. musciformis displayed the highest resistance against the gram-negative bacteria E. coli and the gram-positive bacteria S. epidermidis, whereas the methanolic extract of U. intestinalis demonstrated the highest resistance against the gram-positive bacteria S. aureus. The findings of this investigation show that a range of bioactive compounds with antioxidant properties are involved in the antimicrobial activities of disease-causing pathogens.


Asunto(s)
Antibacterianos , Algas Marinas , Algas Marinas/química , Antibacterianos/farmacología , Escherichia coli/efectos de los fármacos , Staphylococcus epidermidis/efectos de los fármacos , Aspergillus/efectos de los fármacos , Antioxidantes/farmacología
8.
Nat Genet ; 23(2): 237-40, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10508525

RESUMEN

The identification of genes that control susceptibility to testicular germ-cell tumours (TGCTs), the most common cancer affecting young men, has been difficult. In laboratory mice, TGCTs arise from primordial germ cells in only the 129 inbred strains, and susceptibility is under multigenic control. The spontaneously arising mutation Ter (ref. 5) on mouse chromosome 18 (Refs 6,7) increases TGCT frequency on a 129/Sv background. We originally used Ter in genetic crosses to identify loci that control tumorigenesis. A genome scan of tumour-bearing progeny from backcrosses between the 129/Sv-Ter/+ and MOLF/Ei strains provided modest evidence that MOLF-derived alleles on chromosome 19 enhance development of bilateral TGCTs (ref. 9). To obtain independent evidence for linkage to the MOLF chromosome, we made an autosomal chromosome substitution strain (CSS; or 'consomic strain') in which chromosome 19 of 129/Sv+/+ was replaced by its MOLF-derived homologue. The unusually high frequency of TGCTs in this CSS (even in the absence of the Ter mutation) provides evidence confirming the genome survey results, identifies linkage for a naturally occurring strain variant allele that confers susceptibility to TGCTs and illustrates the power of CSSs in complex trait analysis.


Asunto(s)
Cromosomas/genética , Germinoma/genética , Neoplasias Testiculares/genética , Alelos , Animales , Cruzamientos Genéticos , Interpretación Estadística de Datos , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Germinoma/patología , Masculino , Ratones , Ratones Endogámicos , Neoplasias Testiculares/patología
9.
Nat Genet ; 24(3): 221-5, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10700173

RESUMEN

Many valuable animal models of human disease are known and new models are continually being generated in existing inbred strains,. Some disease models are simple mendelian traits, but most have a polygenic basis. The current approach to identifying quantitative trait loci (QTLs) that underlie such traits is to localize them in crosses, construct congenic strains carrying individual QTLs, and finally map and clone the genes. This process is time-consuming and expensive, requiring the genotyping of large crosses and many generations of breeding. Here we describe a different approach in which a panel of chromosome substitution strains (CSSs) is used for QTL mapping. Each of these strains has a single chromosome from the donor strain substituting for the corresponding chromosome in the host strain. We discuss the construction, applications and advantages of CSSs compared with conventional crosses for detecting and analysing QTLs, including those that have weak phenotypic effects.


Asunto(s)
Mapeo Cromosómico , Cromosomas , Endogamia , Carácter Cuantitativo Heredable , Animales , Cruzamientos Genéticos , Marcadores Genéticos , Genoma , Genotipo , Humanos , Ratones , Ratones Endogámicos , Muridae , Fenotipo
10.
Nat Genet ; 12(3): 280-7, 1996 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8589719

RESUMEN

Mice that have been made deficient for the cystic fibrosis transmembrane conductance regulator (Cftr) usually die of intestinal obstruction. We have created Cftr-deficient mice and demonstrate prolonged survival among backcross and intercross progeny with different inbred strains, suggesting that modulation of disease severity is genetically determined. A genome scan showed that the major modifier locus maps near the centromere of mouse chromosome 7. Electrophysiological studies on mice with prolonged survival show that the partial rectification of Cl- and Na+ ion transport abnormalities can be explained in part by up-regulation of a calcium-activated Cl- conductance. Identification of modifier genes in our Cftr(m1HSC)/Cftr(m1HSC) mice should provide important insight into the heterogeneous disease presentation observed among CF patients.


Asunto(s)
Regulador de Conductancia de Transmembrana de Fibrosis Quística/deficiencia , Fibrosis Quística/genética , Animales , Secuencia de Bases , Línea Celular , Cloruros/metabolismo , Mapeo Cromosómico , Colon/patología , Fibrosis Quística/patología , Fibrosis Quística/fisiopatología , Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Cartilla de ADN , Modelos Animales de Enfermedad , Femenino , Íleon/patología , Masculino , Potenciales de la Membrana , Ratones , Ratones Endogámicos , Ratones Mutantes , Datos de Secuencia Molecular , Mutagénesis , Técnicas de Placa-Clamp , Sobrevivientes , Aumento de Peso
11.
Mymensingh Med J ; 22(3): 478-82, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23982536

RESUMEN

This retrospective study was done in the Obstetrics and Gynaecology Department of Bangladesh Medical College hospital during the period of July 2003 to June 2004 in the women suffering from primary and secondary subfertility, who underwent laparoscopy. The aim of this study was to see the laparoscopic findings of internal genitalia and other pelvic structures in subfertile women. The study group comprises 55 cases of which 67.37% of primary and 32.73% were of secondary subfertility. Both the ovaries were normal looking in 41.81% cases. Endometriosis was present in 5.45% of both the ovaries. Corpus luteum was seen in 20% cases on right ovary and in 27.27% cases on left ovary. Laparoscopy shows normal looking fallopian tube in 65.45% cases in right side and 61.81% cases in the left side. Right sided tubal block was in 5.46% and 9.10 % in the left side. Both the tubes were patent in 81.6% cases.


Asunto(s)
Endometriosis/diagnóstico , Enfermedades de las Trompas Uterinas/diagnóstico , Infertilidad Femenina/diagnóstico , Laparoscopía/métodos , Enfermedades del Ovario/diagnóstico , Adulto , Femenino , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Atención Terciaria de Salud
12.
Nat Cell Biol ; 3(9): 802-8, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11533659

RESUMEN

Epidermal growth factor receptor (EGFR) has been detected in the nucleus in many tissues and cell lines. However, the potential functions of nuclear EGFR have largely been overlooked. Here we demonstrate that nuclear EGFR is strongly correlated with highly proliferating activities of tissues. When EGFR was fused to the GAL4 DNA-binding domain, we found that the carboxy terminus of EGFR contained a strong transactivation domain. Moreover, the receptor complex bound and activated AT-rich consensus-sequence-dependent transcription, including the consensus site in cyclin D1 promoter. By using chromatin immunoprecipitation assays, we further demonstrated that nuclear EGFR associated with promoter region of cyclin D1 in vivo. EGFR might therefore function as a transcription factor to activate genes required for highly proliferating activities.


Asunto(s)
Membrana Celular/metabolismo , Factor de Crecimiento Epidérmico/farmacología , Células Epiteliales/citología , Células Epiteliales/fisiología , Receptores ErbB/metabolismo , Factores de Transcripción/metabolismo , Animales , Secuencia de Bases , Sitios de Unión , Mama , Línea Celular , Cromatina/fisiología , Secuencia de Consenso , Receptores ErbB/genética , Femenino , Humanos , Cinética , Ratones , Datos de Secuencia Molecular , Embarazo , Transporte de Proteínas , Proteínas Recombinantes/metabolismo , Transfección , Células Tumorales Cultivadas , Útero/citología , Útero/metabolismo
13.
Mymensingh Med J ; 20(2): 312-5, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21522107

RESUMEN

Melanotic neuroectodermal tumour in infancy is rare, mainly benign with little tendency to recur after excision or effective curettage. This pigmented neoplasm of neural crest origin occurring in infants before 1 year of age. The most common site of occurrence is the anterior maxillary alveolar ridge (70%), following by the skull, brain and mandible. The genital organ is the most frequent extra cranial site. We report a 6 months old male baby with a similar tumour arising from right half of cheek involving the maxilla. We diagnosed the case after histological report. We remove the tumour through a sub-labial incision. The mass was blackish in colour, and was mobilized from all side including from the maxillary sinuses. The author thought that this should be reported for improving the clinical awareness and treatment of pigmented soft tissue mass in children. Almost one year follow up of the patients showed no recurrence.


Asunto(s)
Neoplasias Faciales/diagnóstico , Tumor Neuroectodérmico Melanótico/diagnóstico , Neoplasias Faciales/patología , Neoplasias Faciales/cirugía , Humanos , Lactante , Masculino , Tumor Neuroectodérmico Melanótico/patología , Tumor Neuroectodérmico Melanótico/cirugía
14.
Trop Biomed ; 38(1): 73-80, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33797527

RESUMEN

Acanthamoeba is an opportunistic protozoan pathogen which is found in diverse environment worldwide. Being ubiquitous nature of this amoeba we come across it in our daily life. Acanthamoeba species are recognized as human pathogens; that may cause blinding keratitis and rare but fatal granulomatous encephalitis involving central nervous system. To date, there is not a single report in literature demonstrating anti-Acanthamoeba antibodies among the Saudi population, and thus aim of the present study. Using ELISA, we identified the antibody level in the local population. Our results represent the secretory IgA antiAcanthamoeba in mucosal secretions from 133 individuals aged 15-60 years. The antiAcanthamoeba antibody prevalence rate was > 80%, and no considerable differences were observed between prevalence in males (80.28%) and that in females (80.64%). In addition, environmental sources (soil and water) from the environment of the participants in our study were evaluated for amoeba incidence. The amoeba was identified by morphological characteristics of cysts or trophozoites on non-nutrient agar plates grown with E. coli. Overall, 58.75% of samples from water and 32.85% of those from soil were culture positive for outgrowth of amoeba on non-nutrient agar plates. Furthermore, PCR was carried out with genus-specific primers to confirm the presence of Acanthamoeba DNA. Our results revealed that about 68% of cultures from water and 43% of those from soil were successfully amplified and proved to be amoeba DNA. Interestingly, a few samples yielded more than one product, which suggests that some other amoebic species may be present in the same sample (MAC-W1 and MADW1). To the best of our knowledge, we described for the first time the amoeba isolation from the participant's close environment and antibodies level among Saudi population. Our future studies will be focused on additional molecular characterization of isolated amoeba and their pathogenic potential which could be a possible threat for the community.


Asunto(s)
Acanthamoeba/aislamiento & purificación , Anticuerpos Antiprotozoarios/aislamiento & purificación , Inmunoglobulina A/aislamiento & purificación , Adolescente , Adulto , ADN Protozoario/aislamiento & purificación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Saliva/química , Arabia Saudita , Suelo/parasitología , Agua/parasitología , Adulto Joven
15.
Appl Environ Microbiol ; 76(13): 4136-42, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20435763

RESUMEN

Control of biofilms requires rapid methods to identify compounds effective against them and to isolate resistance-compromised mutants for identifying genes involved in enhanced biofilm resistance. While rapid screening methods for microtiter plate well ("static") biofilms are available, there are no methods for such screening of continuous flow biofilms ("flow biofilms"). Since the latter biofilms more closely approximate natural biofilms, development of a high-throughput (HTP) method for screening them is desirable. We describe here a new method using a device comprised of microfluidic channels and a distributed pneumatic pump (BioFlux) that provides fluid flow to 96 individual biofilms. This device allows fine control of continuous or intermittent fluid flow over a broad range of flow rates, and the use of a standard well plate format provides compatibility with plate readers. We show that use of green fluorescent protein (GFP)-expressing bacteria, staining with propidium iodide, and measurement of fluorescence with a plate reader permit rapid and accurate determination of biofilm viability. The biofilm viability measured with the plate reader agreed with that determined using plate counts, as well as with the results of fluorescence microscope image analysis. Using BioFlux and the plate reader, we were able to rapidly screen the effects of several antimicrobials on the viability of Pseudomonas aeruginosa PAO1 flow biofilms.


Asunto(s)
Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Ensayos Analíticos de Alto Rendimiento/instrumentación , Viabilidad Microbiana , Técnicas Analíticas Microfluídicas/instrumentación , Pseudomonas aeruginosa/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Recuento de Colonia Microbiana , Proteínas Fluorescentes Verdes/metabolismo , Ensayos Analíticos de Alto Rendimiento/métodos , Humanos , Pruebas de Sensibilidad Microbiana , Microscopía Fluorescente , Pseudomonas aeruginosa/fisiología , Pseudomonas fluorescens/fisiología , Escherichia coli Uropatógena/fisiología
16.
BMC Cancer ; 10: 146, 2010 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-20398414

RESUMEN

BACKGROUND: Bacterial targeting of tumours is an important anti-cancer strategy. We previously showed that strain SL7838 of Salmonella typhimurium targets and kills cancer cells. Whether NO generation by the bacteria has a role in SL7838 lethality to cancer cells is explored. This bacterium has the mechanism for generating NO, but also for decomposing it. METHODS: Mechanism underlying Salmonella typhimurium tumour therapy was investigated through in vitro and in vivo studies. NO measurements were conducted either by chemical assays (in vitro) or using Biosensors (in vivo). Cancer cells cytotoxic assay were done by using MTS. Bacterial cell survival and tumour burden were determined using molecular imaging techniques. RESULTS: SL7838 generated nitric oxide (NO) in anaerobic cell suspensions, inside infected cancer cells in vitro and in implanted 4T1 tumours in live mice, the last, as measured using microsensors. Thus, under these conditions, the NO generating pathway is more active than the decomposition pathway. The latter was eliminated, in strain SL7842, by the deletion of hmp- and norV genes, making SL7842 more proficient at generating NO than SL7838. SL7842 killed cancer cells more effectively than SL7838 in vitro, and this was dependent on nitrate availability. This strain was also ca. 100% more effective in treating implanted 4T1 mouse tumours than SL7838. CONCLUSIONS: NO generation capability is important in the killing of cancer cells by Salmonella strains.


Asunto(s)
Terapia Biológica/métodos , Neoplasias/terapia , Óxido Nítrico/metabolismo , Salmonella typhimurium/metabolismo , Animales , Técnicas Biosensibles , Muerte Celular , Línea Celular Tumoral , Supervivencia Celular , Regulación Bacteriana de la Expresión Génica , Humanos , Hidrazinas/farmacología , Ratones , Ratones Endogámicos BALB C , Neoplasias/microbiología , Neoplasias/patología , Donantes de Óxido Nítrico/farmacología , Salmonella typhimurium/genética , Factores de Tiempo , Carga Tumoral
17.
J Basic Clin Physiol Pharmacol ; 21(2): 201-10, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20853601

RESUMEN

The public awareness about cell phone safety increased greatly in the last few years as various reports of potential adverse health effects on humans exposed to radiations emitted from cellular phones were published. The aim of the study was to assess the effect of long term cell phone exposure on physiological and hematological parameters along with its impact on serum lipid profiles and a single call effect on heart rate, blood pressure and SpO2(%) of healthy male medical students. The students were divided into two groups, group I (n=22, age 20.63 +/- 1.17 yrs) comprising first year medical students who were never exposed to cell phones at the time of this study and group II (n=35, age 22.00 +/- 1.56 yrs) consists of final year (fourth year) male medical students who were using cell phone for more than four years before this study. The results showed no significant differences the groups in basal heart rate, systolic blood pressure, SpO2(%), or various hematologic parameters. Acute exposure (single call of cell phone with 900 MHz for 1 minute) in both groups showed a significant increase in peak heart rate in group II as compared with group I and a significant decrease in peak SpO2 (%) in group I as compared with group II. Serum total cholesterol, VLDL-cholesterol, and triglycerides concentration were significantly higher in group II (long term cell phone exposed) than in group I, suggesting a mild alteration of lipid profile among group II subjects.


Asunto(s)
Teléfono Celular , Lípidos/sangre , Antropometría , Recuento de Células Sanguíneas , Índice de Masa Corporal , Colesterol/sangre , Frecuencia Cardíaca/fisiología , Hemodinámica/fisiología , Humanos , India , Masculino , Oxígeno/sangre , Estudiantes de Medicina , Factores de Tiempo , Triglicéridos/sangre , Adulto Joven
18.
Mymensingh Med J ; 19(4): 555-60, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20956899

RESUMEN

Congenital Muscular Torticollis (CMT) is a postural deformity of head and neck detected at birth or shortly after birth, primarily resulting from unilateral shortening of Sternocleidomastoid Muscle (SCM). In neonates and infants, patient may cure conservatively by physiotherapy but surgery is the treatment of choice for children and adolescents. There are various techniques of surgery. Here we show our experience regarding management of congenital muscular torticollis. In the present retrospective case series, fourteen patients of congenital muscular torticollis were treated. The cases were enrolled between Nov' 2005 to Oct' 2007 in Bangabandhu Sheikh Mujib Medical University, Gonosasthaya Somaj Vittik Medical College Hospital, Dhaka and different private clinics of Dhaka city of Bangladesh. Neonates and infants were treated conservatively with physiotherapy and others treated surgically by transection of both sternal and clavicular head of SCM under general anesthesia. Operated patients were released on following post operative day with advised to do physiotherapy. Patients age range from 7 days to 15 years of which ten were female and four male. SCM was shortened in all cases (8 on right side and 6 on left side). Eleven were female and three male. Of 14 patients, 2 neonates, 7 infants and 5 were more than 1 year age. There was no associated anomaly. Out of 9 neonates and infants 8 cured conservatively with physiotherapy and another one significantly improved. Six were treated surgically including one failed physiotherapy. Post operative period was uneventful and there was no complication. Results were evaluated clinically and comments of peers. Most of the patient of congenital muscular torticollis can be treated conservatively during infancy. Division of both sternal and clavicular head of SCM is easy and safe surgical technique for the treatment of CMT of older children and adolescents.


Asunto(s)
Tortícolis , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Modalidades de Fisioterapia , Tortícolis/congénito , Tortícolis/terapia
19.
Mol Cancer Ther ; 8(2): 333-41, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19190118

RESUMEN

We report the discovery of a new prodrug, 6-chloro-9-nitro-5-oxo-5H-benzo(a)phenoxazine (CNOB). This prodrug is efficiently activated by ChrR6, the highly active prodrug activating bacterial enzyme we have previously developed. The CNOB/ChrR6 therapy was effective in killing several cancer cell lines in vitro. It also efficiently treated tumors in mice with up to 40% complete remission. 9-Amino-6-chloro-5H-benzo(a)phenoxazine-5-one (MCHB) was the only product of CNOB reduction by ChrR6. MCHB binds DNA; at nonlethal concentration, it causes cell accumulation in the S phase, and at lethal dose, it induces cell surface Annexin V and caspase-3 and caspase-9 activities. Further, MCHB colocalizes with mitochondria and disrupts their electrochemical potential. Thus, killing by CNOB involves MCHB, which likely induces apoptosis through the mitochondrial pathway. An attractive feature of the CNOB/ChrR6 regimen is that its toxic product, MCHB, is fluorescent. This feature proved helpful in in vitro studies because simple fluorescence measurements provided information on the kinetics of CNOB activation within the cells, MCHB killing mechanism, its generally efficient bystander effect in cells and cell spheroids, and its biodistribution. The emission wavelength of MCHB also permitted its visualization in live animals, allowing noninvasive qualitative imaging of MCHB in mice and the tumor microenvironment. This feature may simplify exploration of barriers to the penetration of MCHB in tumors and their amelioration.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias/tratamiento farmacológico , Nitrorreductasas/uso terapéutico , Oxazinas/uso terapéutico , Profármacos/uso terapéutico , Animales , Anexina A5/metabolismo , Antineoplásicos/farmacología , Efecto Espectador/efectos de los fármacos , Caspasas/metabolismo , Ciclo Celular/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Fluorescencia , Humanos , Cinética , Ratones , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Neoplasias/enzimología , Neoplasias/patología , Oxazinas/farmacología , Profármacos/farmacología , Distribución Tisular/efectos de los fármacos , Resultado del Tratamiento
20.
Mymensingh Med J ; 29(4): 951-955, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33116101

RESUMEN

The incidence of visceral pain among caesarean section can be as high as 50% in sub arachnoid block (SAB) in spite adequate sensory block, which requires conversion to general anesthesia. Different types of adjuvant have been used to augment the effect of local anesthetics but their use is limited due to adverse effects. The effect of intrathecal midazolam along with hyperbaric bupivacaine in sub arachnoid block is less known. So this randomized, double blind study was conducted to evaluate the additive effect of 0.4ml midazolam to 0.5% 3ml bupivacaine on sub arachnoid block in scheduled elective caesarean section. This study demonstrated that the addition of intrathecal 0.4ml midazolam to spinal 0.5% bupivacaine kept all the characteristics of block unaffected, furthermore pain score VAS 3.4±1.3 in Group A and 1.8±1.22 in Group B which is statistically significant, the requirement of intraoperative analgesia and also increased the duration of postoperative analgesia that is 130.3±5.4 minute in Group A, 265.1±3.6 minute in Group B and also statistically significant. Therefore addition of 2.0mg midazolam with 0.5% bupivacaine significantly reduces the VAS score, reduces the intraoperative visceral pain and need of analgesia.


Asunto(s)
Anestesia Raquidea , Anestésicos Locales , Midazolam , Dolor Postoperatorio , Anestésicos Locales/uso terapéutico , Bupivacaína , Cesárea , Método Doble Ciego , Femenino , Humanos , Inyecciones Espinales , Midazolam/uso terapéutico , Dolor Postoperatorio/tratamiento farmacológico , Dolor Postoperatorio/prevención & control , Embarazo , Estudios Prospectivos
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