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1.
J Hum Nutr Diet ; 33(1): 128-137, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31602707

RESUMEN

BACKGROUND: Metabolic syndrome (MetS) is a global public health concern, although its association with the inflammatory potential of the diet is still indefinite. The main objective of the present study was to investigate the association of MetS and its components with the inflammatory potential of the diet in a Croatian working population with sedentary occupations. METHODS: In a cross-sectional study, Croatian workers (n = 366) self-administrated questionnaires for sociodemographic and health-related data. Their anthropometric measurements and fasting blood samples were collected for evaluation of MetS. The inflammatory potential of the diet was assessed with a Dietary Inflammatory Index (DII)® , scored using dietary data collected from a food frequency questionnaire. Multivariable logistic regression analysis, adjusted for sex, age, body mass index, education, smoking, physical activity and energy intake, was used to establish the association between DII and MetS. RESULTS: MetS prevalence was 25% and was significantly associated with a pro-inflammatory diet [mean (SD) 3.28 (1.45); P < 0.01]. The pro-inflammatory diet was statistically associated with women, university degree, moderate physical activity, snacking between meals, central obesity, hypertriglyceridaemia, hypertension, low high-density lipoprotein-cholesterol, MetS prevalence and lower adherence to a Mediterranean diet. Multivariable logistic regression analysis showed a statistically positive association for a one-unit increase in the DII and MetS prevalence (odds ratio = 2.31; 95% confidence interval = 1.61-3.31; P < 0.01) and hypertension (odds ratio = 1.28; 95% confidence interval = 1.01-1.64; P = 0.04). CONCLUSIONS: Further longitudinal studies in different parts of Croatia, including inflammation biomarkers, are needed to enable a more defined view of the inflammatory potential of a diet and its association with various inflammatory-based health conditions. The results obtained in the present study indicate the need for the development of anti-inflammatory dietary interventions for population health protection.


Asunto(s)
Dieta Saludable , Empleo/estadística & datos numéricos , Síndrome Metabólico/epidemiología , Adulto , Antropometría , Biomarcadores/sangre , Factores de Riesgo Cardiometabólico , Croacia/epidemiología , Estudios Transversales , Dieta/efectos adversos , Ayuno/sangre , Femenino , Humanos , Inflamación , Modelos Logísticos , Estudios Longitudinales , Masculino , Síndrome Metabólico/etiología , Persona de Mediana Edad , Oportunidad Relativa , Prevalencia , Encuestas y Cuestionarios
2.
J Microsc ; 252(3): 286-94, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24118045

RESUMEN

Recent studies have suggested that silver nanoparticles (AgNPs) may affect cell DNA structure in in vitro conditions. In this paper, we present the results indicating that AgNPs change nuclear complexity properties in isolated human epithelial buccal cells in a time-dependent manner. Epithelial buccal cells were plated in special tissue culture chamber / slides and were kept at 37°C in an RPMI 1640 cell culture medium supplemented with L-glutamine. The cells were treated with colloidal silver nanoparticles suspended in RPMI 1640 medium at the concentration 15 mg L⁻¹. Digital micrographs of the cell nuclei in a sample of 30 cells were created at five different time steps: before the treatment (controls), immediately after the treatment, as well as 15 , 30 and 60 min after the treatment with AgNPs. For each nuclear structure, values of fractal dimension, lacunarity, circularity, as well as parameters of grey level co-occurrence matrix (GLCM) texture, were determined. The results indicate time-dependent reduction of structural complexity in the cell nuclei after the contact with AgNPs. These findings further suggest that AgNPs, at concentrations present in today's over-the-counter drug products, might have significant effects on the cell genetic material.


Asunto(s)
Núcleo Celular/efectos de los fármacos , Células Epiteliales/citología , Células Epiteliales/efectos de los fármacos , Nanopartículas/metabolismo , Plata/metabolismo , Células Cultivadas , Humanos , Microscopía , Imagen de Lapso de Tiempo
3.
Mol Biol Evol ; 28(3): 1141-55, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21059793

RESUMEN

Sensing the environment and responding appropriately to it are key capabilities for the survival of an organism. All extant organisms must have evolved suitable sensors, signaling systems, and response mechanisms allowing them to survive under the conditions they are likely to encounter. Here, we investigate in detail the evolutionary history of one such system: The phage shock protein (Psp) stress response system is an important part of the stress response machinery in many bacteria, including Escherichia coli K12. Here, we use a systematic analysis of the genes that make up and regulate the Psp system in E. coli in order to elucidate the evolutionary history of the system. We compare gene sharing, sequence evolution, and conservation of protein-coding as well as noncoding DNA sequences and link these to comparative analyses of genome/operon organization across 698 bacterial genomes. Finally, we evaluate experimentally the biological advantage/disadvantage of a simplified version of the Psp system under different oxygen-related environments. Our results suggest that the Psp system evolved around a core response mechanism by gradually co-opting genes into the system to provide more nuanced sensory, signaling, and effector functionalities. We find that recruitment of new genes into the response machinery is closely linked to incorporation of these genes into a psp operon as is seen in E. coli, which contains the bulk of genes involved in the response. The organization of this operon allows for surprising levels of additional transcriptional control and flexibility. The results discussed here suggest that the components of such signaling systems will only be evolutionarily conserved if the overall functionality of the system can be maintained.


Asunto(s)
Escherichia coli K12/genética , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Evolución Molecular , Transactivadores/genética , Transactivadores/metabolismo , Secuencia de Bases , Escherichia coli K12/metabolismo , Proteínas de Escherichia coli/clasificación , Perfilación de la Expresión Génica , Regulación Bacteriana de la Expresión Génica , Estudios de Asociación Genética , Genoma Bacteriano , Inestabilidad Genómica/fisiología , Genómica , Operón , Filogenia , Estrés Fisiológico/fisiología , Transactivadores/clasificación , Transcripción Genética
4.
J BUON ; 17(1): 168-73, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22517713

RESUMEN

PURPOSE: To determine survivin expression patterns in Wilms tumor (WT) and compare it with the expression in normal renal tissue. Also, to analyse cytoplasmic and nuclear survivin expression in relation to histological type, prognostic group and tumor stage. METHODS: Immunohistochemical expression of survivin was analysed in 59 cases of primary WT and in 10 normal kidney specimens, taken from the same patients, but distant from the tumor. RESULTS: 51 out of 59 cases of WT (86.44%) showed decreased cytoplasmic survivin expression and 4 out of 59 cases of WT (6.78%) showed nuclear overexpression of survivin. There was statistically significant difference in the frequency of decreased cytoplasmic expression of survivin in individual components of WT (p=0.005). Decreased cytoplasmic expression of survivin in epithelial, blastemal and stromal component was found significantly more often in low stage WT compared to high stage WT (Fisher exact test, p=0.0002, p=0.002, p=0.002, respectively). There was no statistically significant difference in the frequency of survivin nuclear overexpression between different stages of WT (Fisher exact test, p=0.564), histological types (Fisher exact test, p=0.915), or between different prognostic groups (Fisher exact test, p=1). CONCLUSION: Decreased survivin cytoplasmic expression or nuclear overexpression may be related to favorable prognosis of WT.


Asunto(s)
Proteínas Inhibidoras de la Apoptosis/análisis , Neoplasias Renales/química , Tumor de Wilms/química , Núcleo Celular/química , Niño , Preescolar , Citoplasma/química , Femenino , Humanos , Inmunohistoquímica , Lactante , Neoplasias Renales/mortalidad , Neoplasias Renales/patología , Masculino , Estadificación de Neoplasias , Pronóstico , Survivin , Tumor de Wilms/mortalidad , Tumor de Wilms/patología
5.
J BUON ; 16(4): 727-32, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22331729

RESUMEN

PURPOSE: It is known that expression disorders of cell cycle regulators play an important role in the development and prognosis of various malignant tumors. Cyclin expression changes during the cell cycle. This work aimed to analyse the expression of cyclin E in transitional cell carcinoma (TCC) and also to compare the expression of cyclin E with tumor stage and histological grade as well as to determine possible existence of differences in the expression of cyclin E in TCCs of the upper and lower urothelium. METHODS: Twenty-four cases of TCC of the urinary tract were retrospectively analysed (6 cancers of the renal pelvis, 2 of the ureter and 15 of the bladder; 4 were infiltrative). Immunohistochemical staining for cyclin E of the analysed transitional cancer cells was assessed semiquantitatively: diffuse cyclin E expression + + + (> 50% of all cells), expression in larger groups of cells: + + (up to 50% of all cells), expression in individual cells or small cell clusters: + (<10% of all cells), and absence of expression. Tumor stage was based on clinical and morphological criteria. WHO classification (Lyon 2004) was used for determination of the histological grade. RESULTS: Non-parametric Spearman's correlation showed that there was no statistically significant correlation between tumor stage and expression of cyclin E (ρ = -0331, p> 0.05). Also, no statistically significant correlation between grade and the expression of cyclin E (ρ = -0077, p> 0.05) was found. x2 test results showed no statistically significant difference (x2 = 2.136, p = 0.775) in the expression of cyclin E between upper and lower urothelium. CONCLUSION: This study showed non significant decreased expression of cyclin E with poor differentiation, muscle invasion and upper/lower urothelium. Expression of cyclin E decreased with increasing histological grade and stage of the tumor.


Asunto(s)
Carcinoma de Células Transicionales/metabolismo , Ciclina E/biosíntesis , Neoplasias de la Vejiga Urinaria/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Transicionales/patología , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos , Neoplasias de la Vejiga Urinaria/patología
6.
Oral Dis ; 16(2): 156-9, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19659890

RESUMEN

OBJECTIVES: The aim of this study was to investigate the expression of survivin, an inhibitor of apoptosis, in odontogenic keratocysts and to compare it to the findings in non-neoplastic jaw cysts - periapical cysts, as well as to establish a possible relationship between survivin expression and human cytomegalovirus presence within these cysts. MATERIALS AND METHODS: Samples of 10 odontogenic keratocysts (five positive and five negative for the presence of cytomegalovirus, as determined by polymerase chain reaction) and 10 periapical cysts (five positive and five negative for the cytomegalovirus presence) were analysed. The expression of survivin was assessed by immunohistochemical methods, using monoclonal antibody that selectively recognizes the cytoplasmic form of survivin. RESULTS: All 10 odontogenic keratocysts showed immunostaining for survivin, while all 10 periapical cysts were negative for its presence. There was no correlation between cytomegalovirus presence and expression of survivin within odontogenic keratocysts. CONCLUSION: Survivin may contribute to the aggressive behavior of odontogenic keratocysts, and thus support the emerging opinion of their neoplastic nature.


Asunto(s)
Proteínas Reguladoras de la Apoptosis/análisis , Infecciones por Citomegalovirus/patología , Proteínas Asociadas a Microtúbulos/análisis , Quistes Odontogénicos/patología , Anticuerpos Monoclonales , Tejido Conectivo/patología , Citoplasma/ultraestructura , Citoplasma/virología , Células Epiteliales/patología , Epitelio/patología , Humanos , Inmunohistoquímica , Proteínas Inhibidoras de la Apoptosis , Microscopía Confocal , Quistes Odontogénicos/virología , Quiste Radicular/patología , Quiste Radicular/virología , Survivin
7.
Pathol Res Pract ; 214(10): 1632-1637, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30139556

RESUMEN

Biopsy registries are one of the most important sources of accurate epidemiological data and the clinical presentation of renal diseases. A detailed analysis of clinicopathologic correlations over a period of 20 years (1987-2006) was performed earlier by our centre. The aim of this study was to check the current state and to register possible changes in clinicopathologic findings recorded under better socioeconomical circumstances and new management. Records of 665 renal biopsies performed at our institution were prospectively followed from 2007 to 2014. The results were compared with our previously published data. The average annual incidence of renal biopsies increased by 10% and included more elderly patients. Nephrotic syndrome (NS) remained the most common clinical indication for biopsy, while acute kidney injury participated more frequently than in the previous study (p < 0.001). Membranous nephropathy (MN) was still the most common cause of NS. Primary glomerulonephritis (PGN) remained the most prevalent disease, while MN was the most prevalent PGN. In comparison with the earlier period, MN was a more common diagnosis (p = 0.002), while the prevalence of mesangioproliferative non-IgA nephropathy decreased significantly during the time (p = 0.012). LN remained the most frequent secondary glomerulonephritis. The pathohistological pattern of renal biopsy remained largely unchanged during time. However, acute kidney injury was more frequently an indication for biopsy in the current study. The significant increase of biopsied elderly patients is due to the rise in their relative numbers in our population.


Asunto(s)
Biopsia/estadística & datos numéricos , Enfermedades Renales/diagnóstico , Enfermedades Renales/epidemiología , Adulto , Anciano , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Sistema de Registros , Serbia/epidemiología
8.
Stomatologiia (Mosk) ; 86(2): 47-50, 2007.
Artículo en Ruso | MEDLINE | ID: mdl-17828069

RESUMEN

Zinc-oxide powder mixed with eugenol or cariofillorum oil and sterilized cotton is frequently used in dental practice as surgical bandage for eliminating or dry socket. Osteonecrosis of alveolar bone caused by free eugenol is rare but possible complication. The aim of this paper is to present a patient with maxillary osteonecrosis complicated with maxillary sinusitis caused by a surgical paste of zinc-oxide. A 47-year-old female patient was admitted to our department after unsuccessful treatment of dry socket with a paste of zinc-oxide. Intense use of zinc-oxide paste as bandage over the extraction sockets caused two separately osteonecrosis of maxillary alveolar bone. Surgical resection of necrotic bone, extraction of adjacent teeth and revision surgery of maxillary sinus was treatment of choice. Postoperative course was uneventful and 6 months postoperatively there weren't present further signs of maxillary necrosis. In preparation of a paste of zinc-oxide as surgical bandage it is necessary that all the powder be filled up with intense mixing with liquid. In present case osteonecrosis was caused by free eugenol in surgical zinc-oxide bandage as well as due to the long term and frequently used of zinc-oxide. In resistant dry sockets we recommended combined method of treatment and not only the use of zinc-oxide paste especially if there was no analgesic and therapeutic effects.


Asunto(s)
Enfermedades Maxilares/diagnóstico , Enfermedades Maxilares/cirugía , Osteonecrosis/diagnóstico , Osteonecrosis/cirugía , Cemento de Óxido de Zinc-Eugenol/efectos adversos , Femenino , Humanos , Enfermedades Maxilares/inducido químicamente , Persona de Mediana Edad , Osteonecrosis/inducido químicamente , Resultado del Tratamiento
9.
Folia Biol (Praha) ; 52(5): 173-80, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17116290

RESUMEN

All living beings need to solve the problem of controlled transport of water. To this purpose, a special group of integral membrane proteins called aquaporins has evolved. There are 13 known members of this family that act as channels for water and small solutes, such as glycerol and urea. Although they allow large flux of water, they successfully prevent passage of protons. Here, we present the review of the data from the literature on the selectivity mechanism of aquaporins. The regulation of aquaporin activity occurs through regulation of expression of their genes, changing the localization of the already existing proteins in the cells and direct regulation of the activity in situ. We present the review of new data on the mechanisms of direct regulation. Special emphasis is on the advances in comprehension of aquaporin-2 translocation in collecting tubule cells of the kidney. Four elements of this process are described: 1) the role of protein kinase A and phosphorylation of serine 256 on aquaporin-2, 2) the transport of vesicles along the microtubules toward the apical membrane, 3), the removal of cytoskeletal subapical obstruction and the role of Rho GTPase and ezrin-radixin-moesin proteins in this, and 4) elevation of the cytosolic Ca2+ concentration, the fusion of the vesicle with the apical membrane and the role of SNARE proteins in exocytosis.


Asunto(s)
Acuaporinas/metabolismo , Acuaporinas/fisiología , Transporte Biológico Activo , Regulación de la Expresión Génica , Animales , Acuaporina 2/metabolismo , Acuaporina 2/fisiología , Humanos , Riñón/citología , Riñón/fisiología , Túbulos Renales Colectores/fisiología
10.
Folia Microbiol (Praha) ; 51(6): 535-40, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17455789

RESUMEN

The region of the prtR gene coding for the active site of PrtR proteinase was detected in natural isolates of lactobacilli, previously determined as Lactobacillus rhamnosus. This region was present in all L. rhamnosus strains with proteolytic activity. The PCR primers used were constructed on the basis of the sequence of the catalytic domain of the prtR proteinase gene. These primers generated in colony-PCR procedure specific 611 1-bp product with DNA from natural isolates of L. rhamnosus. No PCR amplifications using these primers were obtained for closely related bacteria of genus Lactobacillus, regardless of their proteolytic activity. In addition, these primers could be used singly or in multiplex PCR together with the Lactobacillus genus-specific primers. Compared with the other proteinases within the genus Lactobacillus (PrtP, PrtB and PrtH) which retained the activity in cell-free proteinase extracts, PrtR proteinase showed proteolytic activity only under in vivo conditions (whole cells of the producing strains).


Asunto(s)
Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Cisteína Endopeptidasas/genética , Cisteína Endopeptidasas/metabolismo , Lacticaseibacillus rhamnosus/enzimología , Proteínas Bacterianas/química , Sitios de Unión/genética , Dominio Catalítico , Cisteína Endopeptidasas/química , Cartilla de ADN , ADN Bacteriano/análisis , ADN Bacteriano/genética , Femenino , Microbiología de Alimentos , Humanos , Lacticaseibacillus rhamnosus/genética , Lacticaseibacillus rhamnosus/aislamiento & purificación , Reacción en Cadena de la Polimerasa , Vagina/microbiología
11.
Curr Med Chem ; 2016 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-26907182

RESUMEN

Free radical-mediated injury releases proinflammatory cytokines and activates innate immunity. It has been suggested that the early innate response and the ischemic tissue damage play roles in the development of adaptive responses, which may lead to acute kidney rejection. Various durations of hypothermic kidney storage before transplantation add to ischemic tissue damage. The final stage of ischemic injury occurs during reperfusion that develops hours or days after the initial insult. Repair and regeneration processes occur together with cellular apoptosis, autophagy and necrosis and a favorable outcome is expected if regeneration prevails. Along the entire transplantation time course, there is a great demand for novel immune and nonimmune injury biomarkers. The use of these markers can be of great help in the monitoring of kidney injury in potential kidney donors, where acute kidney damage can be overlooked, in predicting acute transplant dysfunction during the early post-transplant periods, or in predicting chronic changes in long term followup. Numerous investigations have demonstrated that biomarkers that have the highest predictive value in acute kidney injury include NGAL, Cystatin C, KIM-1, IL-18, and L-FABP. Most investigations show that the ideal biomarker to fulfill all the needs in renal transplant has not been identified yet. Although, in many animal models, new biomarkers are emerging for predicting acute and chronic allograft damage, in human allograft analysis they are still not routinely accepted and renal biopsy still remains the gold standard.

12.
Curr Med Chem ; 23(19): 2012-7, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27498898

RESUMEN

Free radical-mediated injury releases proinflammatory cytokines and activates innate immunity. It has been suggested that the early innate response and the ischemic tissue damage play roles in the development of adaptive responses, which may lead to acute kidney rejection. Various durations of hypothermic kidney storage before transplantation add to ischemic tissue damage. The final stage of ischemic injury occurs during reperfusion that develops hours or days after the initial insult. Repair and regeneration processes occur together with cellular apoptosis, autophagy and necrosis and a favorable outcome is expected if regeneration prevails. Along the entire transplantation time course, there is a great demand for novel immune and nonimmune injury biomarkers. The use of these markers can be of great help in the monitoring of kidney injury in potential kidney donors, where acute kidney damage can be overlooked, in predicting acute transplant dysfunction during the early post-transplant periods, or in predicting chronic changes in long term followup. Numerous investigations have demonstrated that biomarkers that have the highest predictive value in acute kidney injury include NGAL, Cystatin C, KIM-1, IL-18, and L-FABP. Most investigations show that the ideal biomarker to fulfill all the needs in renal transplant has not been identified yet. Although, in many animal models, new biomarkers are emerging for predicting acute and chronic allograft damage, in human allograft analysis they are still not routinely accepted and renal biopsy still remains the gold standard.


Asunto(s)
Lesión Renal Aguda/terapia , Trasplante de Riñón/efectos adversos , Lesión Renal Aguda/metabolismo , Lesión Renal Aguda/patología , Biomarcadores/análisis , Proteínas del Sistema Complemento/metabolismo , Cistatina C/análisis , Proteínas de Unión a Ácidos Grasos/análisis , Receptor Celular 1 del Virus de la Hepatitis A/análisis , Humanos , Interleucina-18/análisis , Lipocalina 2/análisis , Trasplante Homólogo
13.
J Mol Biol ; 273(2): 377-88, 1997 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-9344746

RESUMEN

PspF, the transcriptional activator of the pspA operon of Escherichia coli, which belongs to the enhancer binding protein (EBP) family of sigma54 activator proteins, is constitutively active in an in vitro transcription assay. PspF protein, together with RNA polymerase holoenzyme containing sigma54, is required for in vitro transcription from the pspA promoter. EBP proteins are typically subject to regulation either by post-translational modification or interaction of a specific ligand with an N-terminal regulatory domain. However, unlike other members of the EBP family, PspF lacks this domain. pspA is positively regulated by IHF in vitro, and this regulation is dependent on the topology of the DNA; a linear template is much more dependent on IHF than a supercoiled template. EBP binding to upstream activating sequences (UAS) in their target promoters is mediated by the C-terminal domain which contains a helix-turn-helix DNA-binding motif. A mutant PspF protein lacking the C-terminal DNA-binding domain is active in vitro, although at much higher concentrations than the wild-type protein. In vitro transcription from pspA templates missing one or both of the UAS sites is reduced relative to wild-type templates, but is still appreciable; however, IHF acts as a negative regulator of pspA transcription on these mutant templates. Thus, PspF bound to non-specific sequences upstream of the pspA promoter can activate pspA transcription, but this activation is inhibited by IHF. These data, taken together, support the model that a precise promoter geometry is necessary for IHF to positively regulate transcription and that IHF may act to prevent activation from inappropriately spaced upstream sites.


Asunto(s)
Proteínas Bacterianas/biosíntesis , Proteínas Bacterianas/metabolismo , Proteínas de Escherichia coli , Regulación Bacteriana de la Expresión Génica , Proteínas de Choque Térmico/biosíntesis , Secuencias Reguladoras de Ácidos Nucleicos , Transactivadores/metabolismo , Secuencia de Bases , Proteínas de Unión al ADN/metabolismo , ARN Polimerasas Dirigidas por ADN/metabolismo , Elementos de Facilitación Genéticos , Escherichia coli/genética , Factores de Integración del Huésped , Datos de Secuencia Molecular , Mutación , Regiones Promotoras Genéticas , ARN Polimerasa Sigma 54 , Eliminación de Secuencia , Factor sigma/metabolismo , Volumetría , Transcripción Genética
14.
J Mol Biol ; 285(2): 469-83, 1999 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-9878422

RESUMEN

Transcription of the phage-shock protein (psp) operon in Escherichia coli is driven by a sigma54 promoter, stimulated by integration host factor and dependent on an upstream, cis-acting sequence and an activator protein, PspF. PspF belongs to the enhancer binding protein family but lacks an N-terminal regulatory domain. Purified PspF is not modified and has an ATPase activity that is increased twofold in the presence of DNA carrying the psp cis-acting sequence. Purified mutant His-tagged PspF that lacks the C-terminal DNA-binding motif has a DNA-independent ATPase activity when present at 30-fold the concentration of the wild-type protein. Both proteins oligomerize in solution in an ATP and DNA-independent manner. The wild-type activator protein, but not the DNA-binding mutant, binds specifically to the cis-acting sequence. Analysis of the sequence protected by PspF demonstrates the presence of two upstream binding sites within the sequence, UAS I and UAS II, which together constitute the psp enhancer. Protection at low protein concentrations is more pronounced and more extensive on a supercoiled DNA than on a linear template. Full expression of the psp operon upon hyperosmotic shock depends on wild-type PspF, but only partially requires the presence of the psp enhancer.


Asunto(s)
Proteínas Bacterianas/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas de Escherichia coli , Escherichia coli/genética , Transactivadores/metabolismo , Adenosina Trifosfatasas/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/aislamiento & purificación , Secuencia de Bases , Sitios de Unión , ADN Bacteriano , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/aislamiento & purificación , ARN Polimerasas Dirigidas por ADN/metabolismo , Elementos de Facilitación Genéticos , Proteínas de Choque Térmico/genética , Histidina , Datos de Secuencia Molecular , Mutagénesis , Operón , Presión Osmótica , Regiones Promotoras Genéticas , ARN Polimerasa Sigma 54 , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/aislamiento & purificación , Proteínas Recombinantes de Fusión/metabolismo , Factor sigma/metabolismo , Transactivadores/genética , Transactivadores/aislamiento & purificación
15.
J Mol Biol ; 239(3): 433-5, 1994 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-8201624

RESUMEN

We report on a significant difference between the published nucleotide sequence of the Escherichia coli K12 histidine operon and our sequencing results repeatedly obtained from a number of different E. coli K12 strains. The discrepancies include 39 base-pair changes and one addition located predominantly in the proximal portion of the operon. Our data also suggest that neutral and near-neutral mutations do not accumulate to a significant extent in the histidine operon of E. coli strains harbouring strong mutator alleles.


Asunto(s)
Escherichia coli/genética , Genes Bacterianos/genética , Histidina/genética , Operón/genética , Secuencia de Bases , Mutación/genética , Salmonella typhimurium/genética , Análisis de Secuencia de ADN
16.
Transplant Proc ; 37(2): 734-6, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15848517

RESUMEN

The purpose of the study was to evaluate the impact of conversion from azathioprine (AZA) to mycophenolate mofetil (MMF) on graft function in 35 renal transplant recipients with chronic allograft nephropathy (CAN). The immunosuppressive regimen originally consisted of AZA, cyclosporine (CsA), and prednisone (Pr). At the onset of the study (mean period = 39 posttransplant months), a graft biopsy was performed on all patients who were randomly divided into group 1 (n = 17) in whom MMF was introduced instead of AZA. The remaining 18 subjects (group 2) were maintained on the previous regimen. Two periods were analyzed: period I: 12 months before, and period II: 12 months after biopsy and therapy conversion. Graft function was assessed monthly by measurements of the 24-hour creatinine clearance (CCr). Analysis of variance (ANOVA) was used to compare the differences in CCr and proteinuria between the two groups. No difference was observed in the baseline characteristics, in the incidence of delayed graft function and acute rejection, or in the mean CsA dose. Pathohistological analysis revealed advanced CAN in the majority of patients in both groups. The morphological changes negatively correlated with graft function. The graft function showed parallel deterioration in the two groups; no significant difference was observed in the mean CCr values in the periods studied. Proteinuria was similar for both groups throughout the study. Conversion of AZA to MMF in recipients with CAN, albeit safe, was without significant benefit on the progression of chronic graft failure over the period of a year.


Asunto(s)
Azatioprina/uso terapéutico , Trasplante de Riñón/inmunología , Ácido Micofenólico/análogos & derivados , Enfermedad Aguda , Adulto , Análisis de Varianza , Creatinina/sangre , Progresión de la Enfermedad , Femenino , Rechazo de Injerto/epidemiología , Humanos , Inmunosupresores/uso terapéutico , Trasplante de Riñón/patología , Trasplante de Riñón/fisiología , Masculino , Ácido Micofenólico/uso terapéutico , Diálisis Renal , Trasplante Homólogo/patología , Insuficiencia del Tratamiento , Resultado del Tratamiento
17.
Gene ; 198(1-2): 99-103, 1997 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-9370269

RESUMEN

We describe the use of transcriptional fusions to the phage shock protein (psp) promoter. These fusions are expressed only when cells are infected by filamentous phage. In an application, the psp promoter was fused to the protein coding part of filamentous phage gene III (gIII). Protein III (pIII) is needed to complement mutant f1 phage containing a deletion of gIII, but its synthesis also renders cells resistant to infection. By inducing pIII production from psp-gIII only in the cells that are already infected with phage, it was possible to obtain plaques from phage in which gIII had been completely deleted. gIII was deleted from two helper phages: R408 and VCSM13, which were then propagated on cells containing the psp-gIII fusion. These two phages were tested for use in a phage display method that requires generation of noninfectious, phagemid-containing virion-like particles. Both helpers worked, but R408d3 was superior to VCSM13d3, because it generated about 1800-times fewer background infectious particles.


Asunto(s)
Colifagos/genética , Proteínas de Unión al ADN/genética , Proteínas Virales de Fusión/genética , Proteínas de la Cápside , Regulación Viral de la Expresión Génica , Ingeniería Genética/métodos , Virus Helper/genética , Biblioteca de Péptidos , Plásmidos , Regiones Promotoras Genéticas
18.
Clin Nephrol ; 33(3): 110-4, 1990 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2182230

RESUMEN

We measured the thickness of glomerular basement membrane in 46 patients with thin basement membrane disease (TBMD), (age range 15-50 years, almost equal M:F ratio), and compared with that in a control group of 5 patients (age range 5-38 years) with normal glomerular morphology. The measurements of glomerular basement membrane taken from electron micrographs (magnification x 12,500) were analyzed using an interactive image analysis system assembled around an INTEL 10 microcomputer, with a high resolution touch sensitive screen as the interactive peripheral. Calculation was done by printing on an electron micrograph a grating replica (21,600 lines/cm), with the same magnification as the electron micrographs of the glomeruli and calibrating the arithmetic (AM) and harmonic (HM) mean for each case. Comparing the results of TBMD cases (AM 129-202 nm; HM 128-213 nm) with those of the control group consisting of 5 cases of "minimal change nephrotic syndrome" (AM 287-317 nm; HM 300-333 nm) it was found that GBM in TBMD is remarkably thin. The thinning was caused mainly by the decreased width of the lamina densa (TBMD group: 71.4-147.0 nm; HM 72.4-154.4 nm in comparison with the control group: AM 174.4-235.5 nm; HM 184.2-249.6 nm). This finding allows us to differentiate thin basement membrane disease from other glomerulopathies presenting primarily with isolated or recurrent hematuria.


Asunto(s)
Hematuria/patología , Glomérulos Renales/patología , Glomérulos Renales/ultraestructura , Adolescente , Adulto , Membrana Basal/patología , Membrana Basal/ultraestructura , Niño , Preescolar , Femenino , Técnica del Anticuerpo Fluorescente , Hematuria/complicaciones , Humanos , Masculino , Microscopía Electrónica , Persona de Mediana Edad
19.
Adv Space Res ; 34(7): 1494-8, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15846878

RESUMEN

The conversion of solid waste into useful resources in support of long duration manned missions in space presents serious technological challenges. Several technologies, including supercritical water oxidation, microwave powered combustion and fluidized bed incineration, have been tested for the conversion of solid waste. However, none of these technologies are compatible with microgravity or hypogravity operating conditions. In this paper, we present the gradient magnetically assisted fluidized bed (G-MAFB) as a promising operating platform for fluidized bed operations in the space environment. Our experimental and theoretical work has resulted in both the development of a theoretical model based on fundamental principles for the design of the G-MAFB, and also the practical implementation of the G-MAFB in the filtration and destruction of solid biomass waste particles from liquid streams.


Asunto(s)
Magnetismo , Vuelo Espacial/instrumentación , Administración de Residuos/métodos , Ingravidez , Biomasa , Diseño de Equipo , Filtración/métodos , Gravitación , Modelos Teóricos , Administración de Residuos/instrumentación
20.
Dentomaxillofac Radiol ; 39(6): 383-8, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20729189

RESUMEN

Non-Hodgkin's lymphoma has the propensity to affect non-lymphoid tissue including oral tissue. Primary non-Hodgkin's lymphoma of the mandible mistreated as chronic periodontitis with diffuse enlargement of the mandibular canal and ice-cold numbness is very rarely described in English medical literature. A 57-year-old patient presented with a painful swelling on the left side of the mandible with a clinically chronic periodontitis associated with ice-cold numbness. A panoramic radiograph showed a diffuse uniform enlargement of the mandibular canal. Histological examination showed that the lesion was a primary intraosseous non-Hodgkin's lymphoma of the mandible. Immunohistochemical examination showed a positive reaction for CD20+, Ki-67+. Seven months after chemotherapy the patient was observed for possible life-threatening propagation of the disease. In conclusion, primary (extra-nodal) non-Hodgkin's lymphoma of the mandible usually clinically presents with bone swelling, teeth mobility and neurological disturbance. Radiographic features presenting as diffuse enlargement of the mandibular canal could be considered as non-Hodgkin's lymphoma.


Asunto(s)
Linfoma no Hodgkin/diagnóstico por imagen , Neoplasias Mandibulares/diagnóstico por imagen , Nervio Mandibular/diagnóstico por imagen , Magnificación Radiográfica , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Ciclofosfamida/uso terapéutico , Diagnóstico Diferencial , Doxorrubicina/uso terapéutico , Humanos , Hipoestesia/etiología , Antígeno Ki-67/análisis , Linfoma no Hodgkin/complicaciones , Linfoma no Hodgkin/tratamiento farmacológico , Linfoma no Hodgkin/patología , Masculino , Neoplasias Mandibulares/complicaciones , Neoplasias Mandibulares/tratamiento farmacológico , Neoplasias Mandibulares/patología , Persona de Mediana Edad , Periodontitis/diagnóstico , Prednisona/uso terapéutico , Sensación Térmica , Tomografía Computarizada por Rayos X , Vincristina/uso terapéutico
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