RESUMO
OBJECTIVES: To assess trends in food insecurity between 2005 and 2017-a period including the Great Recession-by participation in the Special Supplemental Nutrition Program for Women, Infants and Children (WIC). METHODS: Data from the California Health Interview Survey (CHIS), 2005-2017, were used, including 7421 households: WIC participants (n = 4184)-those participating in WIC only (n = 2315) and in the Supplemental Nutrition Assistance Program (SNAP) in addition to WIC (n = 1869)-and WIC-eligible non-participants (n = 3237). Multivariable logistic regression models were run with food insecurity as the outcome, WIC participation and survey year as predictors, and adjusted by children's and family's demographic and socioeconomic variables. Interactions between WIC participation and survey year were tested. RESULTS: WIC + SNAP participating households had higher crude food insecurity prevalence across time compared to WIC only and WIC-eligible non-participant households. In fully adjusted models: (1) food insecurity was higher between 2009 and 2017, compared to 2005, for all groups; (2) WIC participating households had higher odds of food insecurity than WIC-eligible non-participants (OR = 1.23, 95%CI = 1.10-1.38); (3) when WIC participants were split into WIC only and WIC + SNAP, WIC + SNAP households had higher odds of food insecurity than WIC-eligible non-participants (OR = 1.45, 95%CI = 1.27-1.66); and (4) the association between food insecurity and WIC participation did not change across time (interaction p-value > 0.10). CONCLUSIONS: Food insecurity increased post-Great Recession among low-income households with children in California, with those participating in WIC, particularly in WIC + SNAP, at higher risk. WIC should consider additional referrals for households who participate in WIC + SNAP.
Assuntos
Assistência Alimentar , Lactente , Criança , Humanos , Feminino , Características da Família , Pobreza , California , Insegurança Alimentar , Abastecimento de AlimentosRESUMO
The formation and analysis of amyloid fibers by two ß-glucosidases, BglA and BglB, belonging to the GH1 enzyme family, are reported. Both proteins have the (ß/α)8 TIM-barrel fold, which is characteristic of this family and is also the most common protein structure. BglA is an octamer, whereas BglB is a monomer. Amyloid fibrillation using pH and temperature as perturbing agents was investigated using fluorescence spectroscopy as a preliminary approach and corroborated using wide-field optical microscopy, confocal microscopy, and field-emission scanning electron microscopy. These analyses showed that both enzymes fibrillate at a wide range of acidic and alkaline conditions and at several temperature conditions, particularly at acidic pH (3-4) and at temperatures between 45 and 65 °C. Circular dichroism spectroscopy corroborated the transition from an α-helix to a ß-sheet secondary structure of both proteins in conditions where fibrillation was observed. Overall, our results suggest that fibrillation is a rather common phenomenon caused by protein misfolding, driven by a transition from an α-helix to a ß-sheet secondary structure, that many proteins can undergo if subjected to conditions that disturb their native conformation.
Assuntos
Amiloide , Amiloide/química , Amiloide/metabolismo , Concentração de Íons de Hidrogênio , Glicosídeo Hidrolases/química , Glicosídeo Hidrolases/metabolismo , Dicroísmo Circular , Temperatura , Estrutura Secundária de Proteína , Dobramento de ProteínaRESUMO
Glaucoma is a neurodegenerative disease that causes blindness. In this study, we aimed to evaluate the protective role of cilastatin (CIL), generally used in the treatment of nephropathologies associated with inflammation, in an experimental mouse model based on unilateral (left) laser-induced ocular hypertension (OHT). Male Swiss mice were administered CIL daily (300 mg/kg, i.p.) two days before OHT surgery until sacrifice 3 or 7 days later. Intraocular Pressure (IOP), as well as retinal ganglion cell (RGC) survival, was registered, and the inflammatory responses of macroglial and microglial cells were studied via immunohistochemical techniques. Results from OHT eyes were compared to normotensive contralateral (CONTRA) and naïve control eyes considering nine retinal areas and all retinal layers. OHT successfully increased IOP values in OHT eyes but not in CONTRA eyes; CIL did not affect IOP values. Surgery induced a higher loss of RGCs in OHT eyes than in CONTRA eyes, while CIL attenuated this loss. Similarly, surgery increased macroglial and microglial activation in OHT eyes and to a lesser extent in CONTRA eyes; CIL prevented both macroglial and microglial activation in OHT and CONTRA eyes. Therefore, CIL arises as a potential effective strategy to reduce OHT-associated damage in the retina of experimental mice.
Assuntos
Glaucoma , Doenças Neurodegenerativas , Hipertensão Ocular , Masculino , Camundongos , Animais , Doenças Neurodegenerativas/complicações , Glaucoma/etiologia , Hipertensão Ocular/tratamento farmacológico , Hipertensão Ocular/patologia , Pressão Intraocular , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Cilastatina/uso terapêutico , Modelos Animais de DoençasRESUMO
PHOSPHORUS-STARVATION TOLERANCE 1 (OsPSTOL1) is a variably present gene that benefits crown root growth and phosphorus (P) sufficiency in rice (Oryza sativa). To explore the ecophysiological importance of this gene, we performed a biogeographic survey of landraces and cultivars, confirming that functional OsPSTOL1 alleles prevail in low nutrient and drought-prone rainfed ecosystems, whereas loss-of-function and absence haplotypes predominate in control-irrigated paddy varieties of east Asia. An evolutionary history analysis of OsPSTOL1 and related genes in cereal, determined it and other genes are kinase-only domain derivatives of membrane-associated receptor like kinases. Finally, to evaluate the potential value of this kinase of unknown function in another Gramineae, wheat (Triticum aestivum) lines overexpressing OsPSTOL1 were evaluated under field and controlled low P conditions. OsPSTOL1 enhances growth, crown root number, and overall root plasticity under low P in wheat. Survey of root and shoot crown transcriptomes at two developmental stages identifies transcription factors that are differentially regulated in OsPSTOL1 wheat that are similarly controlled by the gene in rice. In wheat, OsPSTOL1 alters the timing and amplitude of regulators of root development in dry soils and hastens induction of the core P-starvation response. OsPSTOL1 and related genes may aid more sustainable cultivation of cereal crops.
Assuntos
Oryza , Oryza/genética , Triticum/fisiologia , Fósforo , Ecossistema , Grão Comestível , Fosfatos , Raízes de PlantasRESUMO
BACKGROUND: From 2014-2019, Latin America and the Caribbean had the fastest growth of moderate-to-severe food insecurity than any other region, rising from 22.9% to 31.7%. While the prevalence of food insecurity is higher among women than men in every continent, Latin America has the largest food insecurity gender gap. Factors contributing to this gender inequity include underrepresentation of women in formal employment, heightened burden of dependent care on women, and unequal compensation of labor for women vs. men. The objective of this study was to investigate the association between the gender of the head of the household, employment status of household members, and food insecurity in households with children in a low-income district of Lima, Peru. METHODS: This cross-sectional study was carried out in Villa El Salvador, the fifth largest district in Metropolitan Lima, Peru, where over 20% of the population lives in poverty. Data were collected on a stratified random sample (n = 329) using a household questionnaire, including a validated food security tool (HFIAS). We ran multivariate logistic regression models predicting household food insecurity, with independent variables including gender of household head, education of household head, employment of household head, household-level employment status, age, and weekly food expenses per person. RESULTS: In fully adjusted models, woman-headed households had almost thrice the odds of being food insecure compared to man-headed households. Education also had a significant effect size: a household whose household head did not complete high school was 3.4 times more likely to be food insecure than if they had some post-secondary education. Woman-headed households had a significantly higher proportion of members not formally employed, compared to man-headed households, but employment status was not associated with food insecurity. CONCLUSIONS: Gender of the household head was a major contributing factor to household food insecurity in Villa el Salvador. Gender dynamics affecting opportunities for employment, education, and non-remunerated work should inform national food security policies and interventions with the goal to not only lower food insecurity, but also reduce gender inequities in food insecurity and other nutritional outcomes.
Assuntos
Insegurança Alimentar , Abastecimento de Alimentos , Criança , Estudos Transversais , El Salvador/epidemiologia , Emprego , Feminino , Humanos , Masculino , Peru/epidemiologiaRESUMO
The objective of this study was to investigate the association between household food insecurity and food intake among children who participated in the Special Supplemental Nutrition Program for Women, Infants and Children (WIC), including a sub-sample who also participated in the Supplemental Nutrition Assistance Program (SNAP). Data came from the 2014 and 2017 Los Angeles County WIC Surveys, involving a random sample of WIC participating families in Los Angeles, California. Outcome variables were average daily consumption of fruit, 100% fruit juice, vegetables, milk, other juice, other sweetened drinks, and sweet foods, and frequency of fast-food consumption, as reported by the child's caregiver. Our predictor was household food insecurity, obtained from the 6-item Household Food Security Survey Module. Poisson regression (fruit, 100% fruit juice, vegetables, and milk), Negative Binomial regression (other juice, other sweetened drinks, and sweet foods) and multinomial logistic regression (frequency of fast food) models were run, adjusting for child's age and sex; maternal age, ethnicity and language, education, and employment; and type of WIC participation (WIC only vs. WIC + SNAP). In fully adjusted models, household food insecurity was associated with higher consumption of 100% fruit juice (RR = 1.08, 95%CI = 1.03-1.11), milk (RR = 1.04, 95%CI = 1.01-1.07), other juice (RR = 1.16, 95%CI = 1.08-1.26), other sweetened drinks (RR = 1.28, 95%CI = 1.12-1.46), and sweet foods (RR = 1.09, 95%CI = 1.04-1.14). No significant associations were found between household food insecurity and fruit and vegetable consumption. Nutrition education provided by WIC should continue to emphasize the importance of consuming fresh foods, while limiting foods high in sugar for this young population. Efforts should be made to identify food insecure families at the point of service delivery for enhanced nutrition education and social services referrals.
Assuntos
Assistência Alimentar , Bebidas Adoçadas com Açúcar , Criança , Feminino , Insegurança Alimentar , Abastecimento de Alimentos , Frutas , Humanos , Lactente , VerdurasRESUMO
Ulomoides dermestoides are used as a broad-spectrum medical insect in the alternative treatment of various diseases. Preliminary volatilome studies carried out to date have shown, as the main components, methyl-1,4-benzoquinone, ethyl-1,4-benzoquinone, 1-tridecene, 1-pentadecene, and limonene. This work focused on the production of metabolites and their metabolic variations in U. dermestoides under stress conditions to provide additional valuable information to help better understand the broad-spectrum medical uses. To this end, VOCs were characterized by HS-SPME with PEG and CAR/PDMS fibers, and the first reported insect essential oils were obtained. In HS-SMPE, we found 17 terpenes, six quinones, five alkenes, and four aromatic compounds; in the essential oils, 53 terpenes, 54 carboxylic acids and derivatives, three alkynes, 12 alkenes (1-Pentadecene, EOT1: 77.6% and EOT2: 57.9%), 28 alkanes, nine alkyl disulfides, three aromatic compounds, 19 alcohols, three quinones, and 12 aldehydes were identified. Between both study approaches, a total of 171 secondary metabolites were identified with no previous report for U. dermestoides. A considerable number of the identified metabolites showed previous studies of the activity of pharmacological interest. Therefore, considering the wide variety of activities reported for these metabolites, this work allows a broader vision of the therapeutic potential of U. dermestoides in traditional medicine.
Assuntos
Besouros/química , Insetos/química , Óleos Voláteis/química , Álcoois/química , Aldeídos/química , Animais , Benzoquinonas/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Terpenos/química , Compostos Orgânicos Voláteis/químicaRESUMO
Latin American scientific production related to the COVID-19 epidemic means that only 6% represent publications by Latin American authors, led by countries such as Brazil and Mexico; however, this production is still scarce, so efforts must be doubled to make a substantial contribution to the search for alternatives to address the global health crisis that is now in place.
Assuntos
Autoria , COVID-19 , Editoração/estatística & dados numéricos , Humanos , América LatinaRESUMO
Single-molecule (SM) microscopy is a powerful tool capable of visualizing individual molecules and events in real time. SM imaging may rely on proteins or nucleic acids labelled with a fluorophore. Unfortunately photobleaching of fluorophores leads to irreversible loss of signal, impacting the collection of data from SM experiments. Trace amounts of dissolved oxygen (O2) are the main cause of photobleaching. Oxygen scavenging systems (OSS) have been developed that decrease dissolved O2. Commercial OSS enzyme preparations are frequently contaminated with nucleases that damage nucleic acid substrates. In this protocol, we purify highly active Pseudomonas putida protocatechuate 3,4-dioxygenase (PCD) without nuclease contaminations. Quantitation of Cy3 photostability revealed that PCD with its substrate protocatechuic acid (PCA) increased the fluorophore half-life 100-fold. This low cost purification method of recombinant PCD yields an enzyme superior to commercially available OSS that is effectively free of nuclease activity.
Assuntos
Proteínas de Bactérias , Expressão Gênica , Hidroxibenzoatos/química , Imagem Óptica , Protocatecoate-3,4-Dioxigenase , Pseudomonas putida , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Desoxirribonucleases , Estabilidade Enzimática , Oxigênio/química , Protocatecoate-3,4-Dioxigenase/biossíntese , Protocatecoate-3,4-Dioxigenase/química , Protocatecoate-3,4-Dioxigenase/genética , Protocatecoate-3,4-Dioxigenase/isolamento & purificação , Pseudomonas putida/enzimologia , Pseudomonas putida/genética , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificaçãoRESUMO
3' uridylation is increasingly recognized as a conserved RNA modification process associated with RNA turnover in eukaryotes. 2'-O-methylation on the 3' terminal ribose protects micro(mi)RNAs from 3' truncation and 3' uridylation in Arabidopsis. Previously, we identified HESO1 as the nucleotidyl transferase that uridylates most unmethylated miRNAs in vivo, but substantial 3' tailing of miRNAs still remains in heso1 loss-of-function mutants. In this study, we found that among nine other potential nucleotidyl transferases, UTP:RNA uridylyltransferase 1 (URT1) is the single most predominant nucleotidyl transferase that tails miRNAs. URT1 and HESO1 prefer substrates with different 3' end nucleotides in vitro and act cooperatively to tail different forms of the same miRNAs in vivo. Moreover, both HESO1 and URT1 exhibit nucleotidyl transferase activity on AGO1-bound miRNAs. Although these enzymes are able to add long tails to AGO1-bound miRNAs, the tailed miRNAs remain associated with AGO1. Moreover, tailing of AGO1-bound miRNA165/6 drastically reduces the slicing activity of AGO1-miR165/6, suggesting that tailing reduces miRNA activity. However, monouridylation of miR171a by URT1 endows the miRNA the ability to trigger the biogenesis of secondary siRNAs. Therefore, 3' tailing could affect the activities of miRNAs in addition to leading to miRNA degradation.
Assuntos
Proteínas de Arabidopsis/genética , MicroRNAs/genética , Nucleotidiltransferases/genética , RNA Nucleotidiltransferases/genética , Estabilidade de RNA/genética , Arabidopsis/enzimologia , Arabidopsis/genética , Proteínas Argonautas/genética , Metilação , RNA Interferente Pequeno/genética , Uridina/metabolismoRESUMO
PURPOSE: The aim of this work is to investigate the effects of immersing EBT3 radiochromic film in water and to evaluate its contribution to the total uncertainty in dose determination. MATERIALS AND METHODS: We used 3 cm × 3 cm EBT3 radiochromic films irradiated in the range of 0-70 Gy to study the impact of water immersion on the change in net optical density. These films were placed in a water container for a period of 24 h. The net optical density was measured before (0 h) and after of the immersion in water (1, 3, 6, 12, 18, and 24 h). The absorbance spectrum of the EBT3 radiochromic film was measured at 0 h and 24 h after immersion in water. The uncertainty in dose determination due to the effects of keeping the EBT3 radiochromic film submerged in water at 0, 1, and 24 h were recorded in the red, green, and blue channels. RESULTS: We observed an increase in the net optical density as an effect on the film due to its immersion in water. The penetration of the water at the edges of the radiochromic film was observed to be a function of time during which the film remained in the water. On the other hand, the penetration of water at the edges of the film was found to be independent of irradiation dose. CONCLUSIONS: EBT3 radiochromic film is found more resistant to water penetration through the edges than its predecessors. However, there is evidence that suggest that liquid water damage the Nylon cover layer of the film by changing its optical properties. Therefore, it is recommended to build a new calibration curve for radiochromic films for a specific situation involving dose measurements in liquid water.
Assuntos
Calibragem , Dosimetria Fotográfica/instrumentação , Dosimetria Fotográfica/métodos , Umidade , Água/química , Humanos , Imersão , Doses de Radiação , IncertezaRESUMO
Nanocomposites are materials with unique properties and a wide range of applications. The combination of different nanostructures with traditional materials gives a variety of possibilities that should be analyzed. Especially, functional fluorescent semiconductor quantum dots (QDs) embedded in polymeric matrices have shown promising fluorescence and biocompatibility properties. These hybrid materials can be used in medical applications such as biodiagnostic and bioimaging. In this study, two hydrogels, one of polyethylene glycol diacrylate (PEGDA) and other of polyacrylamide (PAAm), were prepared with quantum dots of CdTe (4 nm of diameter) and characterized. The aim of this research was to analyze the optical properties of the nanocomposites and their cell viability. QDs nanocomposites were fabricated by a free radical polymerization process. The optical studies showed that the nanocomposites have well defined properties of fluorescence. To study the biocompatibility of the nanocomposites, metastatic B16f10 cell line were used and MTT assay was performed. The nanocomposites had a significant improved cell viability compared with QDs solutions.
Assuntos
Resinas Acrílicas/química , Sobrevivência Celular/efeitos dos fármacos , Corantes Fluorescentes/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Nanocompostos/química , Pontos Quânticos/química , Resinas Acrílicas/toxicidade , Animais , Compostos de Cádmio/química , Linhagem Celular Tumoral , Corantes Fluorescentes/toxicidade , Hidrogel de Polietilenoglicol-Dimetacrilato/toxicidade , Camundongos , Nanocompostos/toxicidade , Tamanho da Partícula , Pontos Quânticos/toxicidade , Telúrio/químicaRESUMO
INTRODUCTION AND HYPOTHESIS: Pelvic floor muscle training (PFMT) is widely recommended as first-line therapy for women with urinary incontinence. However, adherence to PFMT decreases over time, and information regarding barriers to PFMT is scarce. The primary aim of our study was to investigate whether a vaginal spheres device helped improve adherence to PFMT. The secondary aim was to assess determinants of adherence and the association with treatment outcome. METHODS: This was a secondary analysis of a randomized trial with a 6-month follow-up in women with urinary incontinence (UI) in whom we evaluated adherence to PFMT, performed either with (spheres group) or without (control group) vaginal spheres. The Morisky-Green Questionnaire (MGQ) was used to assess adherence, defined as the extent to which participants corresponded to the agreed recommendations; participants were classified as adherent or nonadherent according to their responses. Efficacy of PFMT was assessed using the International Consultation on Incontinence Questionnaire Short Form scale (ICIQ-SF). RESULTS: Seventy women were enrolled and data from 65 (35 treated and 30 controls) were suitable for analysis. There were no significant differences in adherence to treatment between groups at the end of follow-up (33.3 % in controls and 42.9 % in spheres). The largest group of nonadherent women in both arms were those who mainly forgot to do the exercises. ICIQ-SF results between adherent and nonadherent women did not differ significantly [mean 0.55, 95 % confidence interval (CI) 1.13-2.25]. No significant difference was observed between women who attained greater and lesser improvement in UI after treatment (4.5 %; 95 % CI -11.7 to 20.6). CONCLUSIONS: In patients with UI, vaginal spheres as an adjunct to PFMT did not increase adherence to pelvic muscle exercises. Lack of persistence appeared to be due to forgetfulness and did not seem to be influenced by the efficacy of PFMT.
Assuntos
Terapia por Exercício/instrumentação , Terapia por Exercício/psicologia , Cooperação do Paciente , Incontinência Urinária/psicologia , Incontinência Urinária/terapia , Adulto , Terapia por Exercício/métodos , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Diafragma da Pelve/fisiopatologia , Espanha , Inquéritos e Questionários , Resultado do Tratamento , Incontinência Urinária/fisiopatologia , VaginaRESUMO
Sophisticated systems for cell-cell communication enable unicellular microbes to act as multicellular entities capable of group-level behaviors that are not evident in individuals. These group behaviors influence microbe physiology, and the underlying signaling pathways are considered potential drug targets in microbial pathogens. Trypanosoma brucei is a protozoan parasite that causes substantial human suffering and economic hardship in some of the most impoverished regions of the world. T. brucei lives on host tissue surfaces during transmission through its tsetse fly vector, and cultivation on surfaces causes the parasites to assemble into multicellular communities in which individual cells coordinate their movements in response to external signals. This behavior is termed "social motility," based on its similarities with surface-induced social motility in bacteria, and it demonstrates that trypanosomes are capable of group-level behavior. Mechanisms governing T. brucei social motility are unknown. Here we report that a subset of receptor-type adenylate cyclases (ACs) in the trypanosome flagellum regulate social motility. RNA interference-mediated knockdown of adenylate cyclase 6 (AC6), or dual knockdown of AC1 and AC2, causes a hypersocial phenotype but has no discernible effect on individual cells in suspension culture. Mutation of the AC6 catalytic domain phenocopies AC6 knockdown, demonstrating that loss of adenylate cyclase activity is responsible for the phenotype. Notably, knockdown of other ACs did not affect social motility, indicating segregation of AC functions. These studies reveal interesting parallels in systems that control social behavior in trypanosomes and bacteria and provide insight into a feature of parasite biology that may be exploited for novel intervention strategies.
Assuntos
Adenilil Ciclases/metabolismo , Proteínas de Protozoários/metabolismo , Trypanosoma brucei brucei/fisiologia , Adenilil Ciclases/química , Adenilil Ciclases/genética , Animais , Domínio Catalítico , Linhagem Celular Tumoral , Humanos , Proteínas de Protozoários/química , Proteínas de Protozoários/genética , Trypanosoma brucei brucei/enzimologia , Trypanosoma brucei brucei/patogenicidade , Moscas Tsé-Tsé/parasitologiaRESUMO
Radiochromic film has become an important tool to verify dose distributions for intensity-modulated radiotherapy (IMRT) and quality assurance (QA) procedures. A new radiochromic film model, EBT3, has recently become available, whose composition and thickness of the sensitive layer are the same as those of previous EBT2 films. However, a matte polyester layer was added to EBT3 to prevent the formation of Newton's rings. Furthermore, the symmetrical design of EBT3 allows the user to eliminate side-orientation dependence. This film and the flatbed scanner, Epson Perfection V750, form a dosimetry system whose intrinsic characteristics were studied in this work. In addition, uncertainties associated with these intrinsic characteristics and the total uncertainty of the dosimetry system were determined. The analysis of the response of the radiochromic film (net optical density) and the fitting of the experimental data to a potential function yielded an uncertainty of 2.6%, 4.3%, and 4.1% for the red, green, and blue channels, respectively. In this work, the dosimetry system presents an uncertainty in resolving the dose of 1.8% for doses greater than 0.8 Gy and less than 6 Gy for red channel. The films irradiated between 0 and 120 Gy show differences in the response when scanned in portrait or landscape mode; less uncertainty was found when using the portrait mode. The response of the film depended on the position on the bed of the scanner, contributing an uncertainty of 2% for the red, 3% for the green, and 4.5% for the blue when placing the film around the center of the bed of scanner. Furthermore, the uniformity and reproducibility radiochromic film and reproducibility of the response of the scanner contribute less than 1% to the overall uncertainty in dose. Finally, the total dose uncertainty was 3.2%, 4.9%, and 5.2% for red, green, and blue channels, respectively. The above uncertainty values were obtained by mini-mizing the contribution to the total dose uncertainty of the film orientation and film homogeneity.
Assuntos
Dosimetria Fotográfica/instrumentação , Modelos Teóricos , Garantia da Qualidade dos Cuidados de Saúde/normas , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/instrumentação , Calibragem , Dosimetria Fotográfica/métodos , Humanos , Doses de Radiação , Radioterapia de Intensidade Modulada/métodos , IncertezaRESUMO
Bundles of taxol-stabilized microtubules (MTs)--hollow tubules comprised of assembled αß-tubulin heterodimers--spontaneously assemble above a critical concentration of tetravalent spermine and are stable over long times at room temperature. Here we report that at concentrations of spermine several-fold higher the MT bundles (B(MT)) quickly become unstable and undergo a shape transformation to bundles of inverted tubulin tubules (B(ITT)), the outside surface of which corresponds to the inner surface of the B(MT) tubules. Using transmission electron microscopy and synchrotron small-angle X-ray scattering, we quantitatively determined both the nature of the B(MT)-to-B(ITT) transformation pathway, which results from a spermine-triggered conformation switch from straight to curved in the constituent taxol-stabilized tubulin oligomers, and the structure of the B(ITT) phase, which is formed of tubules of helical tubulin oligomers. Inverted tubulin tubules provide a platform for studies requiring exposure and availability of the inside, luminal surface of MTs to MT-targeted drugs and MT-associated proteins.
Assuntos
Microtúbulos/química , Microtúbulos/ultraestrutura , Paclitaxel/química , Tubulina (Proteína)/química , Tubulina (Proteína)/ultraestrutura , Animais , Sítios de Ligação , Bovinos , Ligação ProteicaRESUMO
AIMS: To compare the efficacy and safety of Kegel exercises performed with or without, vaginal spheres as treatment for women with urinary incontinence. METHODS: Multicentre parallel-group, open, randomized controlled trial. Women were allocated to either a pelvic floor muscle-training program consisting of Kegel exercises performed twice daily, 5 days/week at home, over 6 months with vaginal spheres, or to the same program without spheres. The primary endpoint was women's report of urinary incontinence at 6 months using the International Consultation on Incontinence Questionnaire-Short Form (ICIQ-UI-SF). Secondary outcome measures were the 1 hr pad-test, King's Health Questionnaire (KHQ) and a five-point Likert scale for subjective evaluation. Adherence was measured with the Morisky-Green test. RESULTS: Thirty-seven women were randomized to the spheres group and 33 to the control group. The primary endpoint was evaluated in 65 women (35 in the spheres group vs. 30 controls). ICIQ-UI-SF results improved significantly at 1-month follow-up in the spheres group (P < 0.01) and at 6 months in the controls. The 1 hr pad-test improved in the spheres group but not in the control group. No significant differences were found in the KHQ results or in the subjective evaluation of efficacy and safety. Adherence was higher in the spheres group but differences were not significant. Mild transient side effects were reported in four patients in the spheres group and one in the control group. CONCLUSIONS: Both treatments improved urinary incontinence but women who performed the exercises with vaginal spheres showed an earlier improvement. Vaginal spheres were well tolerated and safe.
Assuntos
Terapia por Exercício/métodos , Diafragma da Pelve , Incontinência Urinária/terapia , Vagina/cirurgia , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Cooperação do Paciente , Projetos Piloto , Estudos Prospectivos , Resultado do TratamentoRESUMO
OBJECTIVES: The aim of this study is to analyze mitochondrial DNA and Y-chromosome lineages in a range of Atlantic and Mediterranean populations of the Iberian Peninsula in search of genetic differences between both façades and to uncover the most probable geographic origin and coalescence ages of lineages. METHODS: The control region of mitochondrial DNA and haplogroup diagnostic positions were analyzed in 575 subjects and Y-chromosome markers were typed in 260 unrelated males. Moreover, previously published data were compiled and used in the analyses. RESULTS: The level of genetic structure deduced from uniparental markers for the Iberian Peninsula was weak, with stronger Atlantic versus Mediterranean than North to South differentiation and larger diversities in the South. In general, mitochondrial DNA haplogroups had mainly Paleolithic and Mesolithic coalescences in Europe, although some of them, ruling out drift effects, seem to have younger implantation in Central Europe and the Atlantic areas than in the Mediterranean (I, J, J2a, T1, and W) while others as N1 and X could have reached the Iberian Peninsula at the Neolithic transition. On the other hand, younger coalescence ages are being proposed for the arriving or spread of the bulk of Y-chromosome lineages in Europe. CONCLUSIONS: The major haplotypic affinities found for all the Iberian Peninsula regions were always with North Africa and the Atlantic Islands. These results draw an Atlantic network that clearly resembles those of the Megalithic Copper and Bronze cultures at this part of Europe.
Assuntos
Cromossomos Humanos Y/genética , DNA Mitocondrial/genética , Haplótipos , Polimorfismo de Fragmento de Restrição , Feminino , Humanos , Masculino , Reação em Cadeia da Polimerase , Portugal , Análise de Sequência de DNA , EspanhaRESUMO
Urinary tract infections (UTIs) are caused mainly by uropathogenic Escherichia coli (UPEC), accounting for both uncomplicated (75%) and complicated (65%) UTIs. Detecting UPEC in a specific, rapid, and timely manner is essential for eradication, and optical biosensors may be useful tools for detecting UPEC. Recently, biosensors have been developed for the selective detection of antigen-antibody-specific interactions. In this study, a methodology based on the principle of an optical biosensor was developed to identify specific biomolecules, such as the PapG protein, which is located at the tip of P fimbriae and promotes the interaction of UPEC with the uroepithelium of the human kidney during a UTI. For biosensor construction, recombinant PapG protein was generated and polyclonal anti-PapG antibodies were obtained. The biosensor was fabricated in silicon supports because its surface and anchor biomolecules can be modified through its various properties. The fabrication process was carried out using self-assembled monolayers (SAMs) and an immobilized bioreceptor (anti-PapG) to detect the PapG protein. Each stage of biosensor development was evaluated by Fourier transform infrared (FTIR) spectroscopy. The infrared spectra showed bands corresponding to the C-H, C=O, and amide II bonds, revealing the presence of the PapG protein. Then, the spectra of the second derivative were obtained from 1600 to 1700 cm-1 to specifically determine the interactions that occur in the secondary structures between the biological recognition element (anti-PapG antibodies) and the analyte (PapG protein) complex. The analyzed secondary structure showed ß-sheets and ß-turns during the detection of the PapG protein. Our data suggest that the PapG protein can be detected through an optical biosensor and that the biosensor exhibited high specificity for the detection of UPEC strains. Furthermore, these studies provide initial support for the development of more specific biosensors that can be applied in the future for the detection of clinical UPEC samples associated with ITUs.