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1.
ACS Mater Au ; 4(2): 107, 2024 Mar 13.
Article in English | MEDLINE | ID: mdl-38496051
2.
J Urban Health ; 100(3): 513-524, 2023 06.
Article in English | MEDLINE | ID: mdl-37213068

ABSTRACT

Understanding temporal and spatial trends in pregnancy and birth outcomes within an urban area is important for the monitoring of health indicators of a population. We conducted a retrospective cohort study of all births in the public hospital of Temuco, a medium-sized city in Southern Chile between 2009 and 2016 (n = 17,237). Information on adverse pregnancy and birth outcomes, as well as spatial and maternal characteristics (insurance type, employment, smoking, age, and overweight/obesity), was collected from medical charts. Home addresses were geocoded and assigned to neighborhood. We tested whether births and prevalence of adverse pregnancy outcomes changed over time, whether birth events were spatially clustered (Moran's I statistic), and whether neighborhood deprivation was correlated to outcomes (Spearman's rho). We observed decreases in eclampsia, hypertensive disorders of pregnancy, and small for gestational age, while gestational diabetes, preterm birth, and low birth weight increased over the study period (all p < 0.01 for trend), with little changes after adjusting for maternal characteristics. We observed neighborhood clusters for birth rate, preterm birth, and low birth weight. Neighborhood deprivation was negatively correlated with low birth weight and preterm birth, but not correlated with eclampsia, preeclampsia, hypertensive disorders of pregnancy, small for gestational age, gestational diabetes, nor stillbirth. Several encouraging downward trends and some increases in adverse pregnancy and birth outcomes, which, overall, were not explained by changes in maternal characteristics were observed. Identified clusters of higher adverse birth outcomes may be used to evaluate preventive health coverage in this setting.


Subject(s)
Diabetes, Gestational , Eclampsia , Hypertension, Pregnancy-Induced , Premature Birth , Pregnancy , Female , Infant, Newborn , Humans , Premature Birth/epidemiology , Retrospective Studies , Chile/epidemiology , Pregnancy Outcome/epidemiology , Hospitals, Public
3.
Int J Health Sci (Qassim) ; 17(2): 28-36, 2023.
Article in English | MEDLINE | ID: mdl-36891043

ABSTRACT

Objective: The prostate-specific antigen (PSA) is the primary biomarker to diagnose prostate cancer. Hepcidin has been reported as an alternative for this diagnosis; however, it is unclear how PSA and hepcidin function at high altitude (HA). This study aims to assess the association between hepcidin with PSA in HA residents chronically exposed to hypobaric hypoxia. Methods: We retrospectively examined data of 70 healthy males (aged 18-65-years-old) from four different altitudes cities in Peru: Lima (<150 m), Huancayo (2380 m), Puno (3800 m), and Cerro de Pasco (4320 m). Serum hepcidin, testosterone, and PSA were analyzed by chemiluminescence immunoassay. HA parameters (hemoglobin [Hb], pulse oxygen saturation [SpO2], and chronic mountain sickness [CMS] score) were also included in the study. Bivariate analyses and a multivariate linear mixed model were used to evaluate the association between hepcidin and PSA, adjusted by HA parameters, age, and body mass index (BMI). Results: Cases of excessive erythrocytosis (EE) (Hb >21 g/dL) were observed in the three highest cities. Hepcidin was positively correlated with Hb, CMS score, and BMI (P ≤ 0.05). Hepcidin was higher in Huancayo with respect to Puno, while PSA was lower in Cerro de Pasco in regard to Puno and Lima (P ≤ 0.05). Neither hepcidin nor PSA was increased by altitude in each city (P > 0.05). We did not find an association between hepcidin and PSA, even adjusted by age, BMI, Hb, and SpO2 (P ≤ 0.05). Conclusion: These findings showed no association between hepcidin and PSA levels in healthy residents at HA.

4.
Article in English | LILACS, COLNAL | ID: biblio-1537194

ABSTRACT

Introduction: Non-prescription tranquilizers are a specific group of benzodiazepines, used as drugs that act on the central nervous system and have an extensive effect in patients with anxiety disorders and problems in sleep stages. Objective: To determine the prevalence of the year and month of consumption of tranquilizers without a medical prescription and the associated factors, in adolescents in school in Colombia. Methods: It is a cross-sec-tional study with an analytical scope. The universe of the study consisted of 3,243,377 students, from grades 7 to 11 (aged between 12 and 18 years), the valid surveys were 80,018. The adolescent who declared having used tranquilizers during the last 30 days and the last 12 months was considered a consumer. All variables were self-re-ported by adolescents. Results: The prevalence of tranquilizer use without medical prescription was 1.02% and 1.97% (month and year, respectively). Adolescents who presented disciplinary problems are the most predisposed to use during the last month with an OR 2.79 (95% CI: 2.20­3.53) and last year an OR of 2.77 (95 % CI: 2.34­3.27). Conclusions: There is a higher prevalence of the consumption of tranquilizers without medical prescription in women between 14 and 17 years of age, from mixed schools and it is associated with academic and disciplinary performance problems, in the last year. In addition, as age increases, the consumption of substances without a medical prescription increases


Introducción: Los tranquilizantes sin prescripción médica son un grupo específico de benzodiacepinas, usados como medicamentos que actúan sobre el sistema nervioso central y cuentan con un extenso efecto en pacientes con trastornos de ansiedad y problemas en las etapas del sueño. Objetivo: Determinar la prevalencia de año y mes de consumo de tranquilizantes sin prescripción médica y los factores asociados en adolescentes escolarizados de Colombia. Métodos: Estudio transversal con alcance analítico. El universo del estudio estuvo constituido por 3 243 377 estudiantes de los gados 7.º a 11.º (con edades entre 12 y 18 años). Las encuestas válidas fueron 80 018. Se consideró consumidor al adolescente que declaró haber consumido tranquilizantes durante los últimos 30 días y los últimos 12 meses. Todas las variables fueron autorreportadas por los adolescentes. Resultados: La prevalencia de consumo de tranquilizantes sin prescripción médica fue del 1,02 % y del 1,97 % (mes y año, respectivamente). Los adolescentes que presentaron problemas disciplinarios son los más predispuestos al consumo durante el último mes con un OR de 2,79 (IC95 %: 2,20-3,53) y último año un OR de 2,77 (IC95 %: 2,34-3,27). Conclusiones: Existe mayor prevalencia de consumo de tranquilizantes sin prescripción médica en mujeres entre los 14 y los 17 años, de colegios mixtos, y se encuentra asociada con problemas de rendimiento académico y disciplinarios, en el último año. Además, a medida que aumenta la edad, se incrementa el consumo de sustancias sin prescripción médica


Introdução: Os tranquilizantes isentos de prescrição são um grupo específico de benzodiazepínicos, usados como medicamentos que atuam no sistema nervoso central e têm um efeito extenso em pa-cientes com transtornos de ansiedade e problemas no estágio do sono. Objetivo: Determinar a prevalência anual e mensal do uso de tranquilizantes sem prescrição médica e os fatores associados em adolescentes em idade escolar na Colômbia. Métodos: Estudo transversal com escopo analítico. O universo do estudo consistiu em 3243377 alunos da 7ª à 11ª série (com idades entre 12 e 18 anos). Foram realizadas 80018 pesquisas válidas. Um adolescente foi considerado usuário, o qual relatou ter usado tranquilizantes nos últimos 30 dias e nos últimos 12 meses. Todas as variáveis foram autorrelatadas pelos adolescentes. Resultados: A prevalência do uso de tranquilizantes sem prescrição médica foi de 1,02% e 1,97% (mês e ano, respectivamente). Os adolescentes com problemas disciplinares apresentaram maior pro-babilidade de uso no último mês, com um OR de 2,79 (IC95%: 2,20-3,53) e no último ano, com um OR de 2,77 (IC95%: 2,34-3,27). Conclusões: Há uma maior prevalência de uso de tranquilizantes sem prescrição médica em mulheres de 14 a 17 anos, de escolas mistas, e isso está associado a problemas de desempenho acadêmico e disciplinar no último ano. Além disso, com o aumento da idade, aumenta o uso de substâncias sem prescrição médica.


Subject(s)
Tranquilizing Agents , Benzodiazepines , Cross-Sectional Studies , Adolescent Behavior , Nonprescription Drugs
6.
Anal Chem ; 94(45): 15553-15557, 2022 11 15.
Article in English | MEDLINE | ID: mdl-36253365

ABSTRACT

Macromolecular association is crucial to many fields in biomedical sciences, including drug development, gene editing, and diagnostics. In particular, protein-protein association and dissociation rate constants are typically determined using surface plasmon resonance systems, which require costly instrumentation and cumbersome procedures (e.g., blocking, washing, and separation). Herein, we demonstrate that protein-binding constants can be readily determined using a real-time biosensing platform facilitated by graphene oxide-modified microwell plates and fluorophore-labeled proteins, where the fluorescent probes remain highly fluorescent during protein association, whereas fluorescent bioprobes that are not associated with their counterparts are quenched by graphene oxide. Binding data of three pairs of proteins were systematically determined employing this single-step platform and compared with those data reported by the suppliers or the literature, suggesting that this approach is comparable and consistent with the existing ones. Such pairs include (i) human immunoglobulin G (H-IgG)-fluorophore-labeled anti-H-IgG, (ii) prostate-specific antigen (PSA)-quantum dot-labeled anti-PSA, and (iii) anti-RBD-fluorophore-labeled SARS-CoV-2 spike receptor-binding domain recombinant protein. We also offer an open-source software that automatically determines the binding kinetics constants of proteins. This Technical Note introduces a simple, yet effective, platform to determine relevant information on protein kinetics, which can be performed using a microwell plate reader and economical materials like graphene oxide. We foresee a new generation of diagnostics based on our affordable protein kinetics analysis.


Subject(s)
Biosensing Techniques , COVID-19 , Humans , Male , SARS-CoV-2 , Kinetics , Fluorescent Dyes , Immunoglobulin G/chemistry
7.
rev. udca actual. divulg. cient ; 25(1): e1947, ene.-jun. 2022. graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1395198

ABSTRACT

RESUMEN Las herramientas automatizadas de análisis de texto resumen grandes volúmenes de información y permiten generar, de forma eficiente, conocimiento a partir de datos desestructurados, como las opiniones. El objetivo de este trabajo fue identificar prioridades en comunidades afectadas por el conflicto armado, utilizando ejercicios participativos de 13 municipios de Antioquia, Colombia. Se analizaron 15.534 opiniones, de 9.765 personas; tras una limpieza de texto, se describió el uso, la asociación, la diferenciación y la importancia de los términos, según los enfoques temáticos y tipos de opinión expresados, utilizando minería de texto en R. Se encontró que las prioridades giraban en torno a la disponibilidad de infraestructuras, dotación e insumos, ya que eran las problemáticas más mencionadas por las comunidades y correspondía con la realidad territorial; por otra parte, las oportunidades estaban representadas, principalmente, por los recursos naturales y humanos. El análisis de minería de texto del ejercicio participativo permitió identificar las prioridades de las comunidades, a nivel socioeconómico, de forma satisfactoria; sin embargo, la preparación de la información requiere mucho trabajo y los resultados se deben revisar cuidadosamente, para asegurar su coherencia. Que la información pueda ser analizada por agentes externos a la colección de datos, representa otra ventaja de esta herramienta.


ABSTRACT Automated text analysis tools summarize large volumes of information and allow efficient generation of insights from unstructured data such as opinions. The objective of this work was to identify priorities in communities affected by the armed conflict using participatory exercises in 13 municipalities of Antioquia, Colombia. 15,534 opinions from 9,765 people were analyzed. After a text cleaning, the use, association, differentiation and importance of the terms were described according to the thematic approaches and types of opinion expressed using text mining in R. It was found that the priorities revolved around the availability of infrastructures, endowment and inputs, since they were the most mentioned problems by the communities, and that this corresponded to the territorial reality. On the other hand, the opportunities were mainly represented by natural and human resources. The text mining analysis of the participatory exercise allowed to identify the priorities of the communities at the socio-economic level in a satisfactory way. However, the preparation of the information is labor intensive and the results must be carefully reviewed to ensure consistency. Another advantage of this tool is that the information can be analyzed by external agents to the data collection.

8.
Curr Vasc Pharmacol ; 20(3): 303-309, 2022.
Article in English | MEDLINE | ID: mdl-35538839

ABSTRACT

BACKGROUND: Testicular aches have been reported to occur on exposure to high altitude (HA). As a painful expression of venous congestion at the pampiniform plexus, varicocele (VC) might be a consequence of cardiovascular adjustments at HA. Chile's National Social Security Regulatory Body (SUSESO) emphasized evaluating this condition in the running follow-up study "Health effects of exposure to chronic intermittent hypoxia in Chilean mining workers." OBJECTIVES: This study aimed at investigating the prevalence of VC in a population usually shifting between sea level and HA, thereby intermittently being exposed to hypobaric hypoxia. METHODOLOGY: Miners (n=492) agreed to be examined at their working place by a physician, in the context of a general health survey, for the presence of palpable VC, either visible or not. Among them was a group exposed to low altitude (LA) <2,400 m; n=123; another one exposed to moderate high altitude (MHA) working 3,050 m; n=70, and a third one exposed to very high altitude (VHA) >3,900 m, n=165. The Chi2 test and Kruskal-Wallis test were used for the descriptive analyses, and logistic regression was applied to evaluate the association of VC with exposure to HA. The Ethics Committee for Research in Human Beings, Faculty of Medicine, University of Chile, approved this project. RESULTS: VC prevalence (grades 2 and 3) was found to be 10% at LA, 4.1% at MHA, and 16.7% at VHA (p≤0.05). Hemoglobin oxygen saturation (SaO2) was lower, and hemoglobin concentrations were higher in workers with high-grade VC at VHA compared to LA and MHA (Wilcoxon tests, p<0.001). Odds ratios (OR) for the association of VC with HA were 3.7 (95%CI: 1.26 to 12.3) and 4.06 (95%CI: 1.73 to 11.2) for MHA and VHA, respectively. CONCLUSION: Association of VC with HA, a clinically relevant finding, may be related to blood volume centralization mediated by hypobaric hypoxia.


Subject(s)
Altitude , Varicocele , Follow-Up Studies , Hemoglobins , Humans , Hypoxia/epidemiology , Male , Varicocele/complications , Varicocele/diagnosis , Varicocele/epidemiology
10.
Biol Reprod ; 106(3): 385-396, 2022 03 19.
Article in English | MEDLINE | ID: mdl-34725677

ABSTRACT

Living at high altitudes and living with prostatic illness are two different conditions closely related to a hypoxic environment. People at high altitudes exposed to acute, chronic or intermittent hypobaric hypoxia turn on several mechanisms at the system, cellular, and molecular level to cope with oxygen atmosphere scarcity maintaining the oxygen homeostasis. This exposure affects the whole organism and function of many systems, such as cardiovascular, respiratory, and reproductive. On the other hand, malignant prostate is related to the scarcity of oxygen in the tissue microenvironment due to its low availability and high consumption due to the swift cell proliferation rates. Based on the literature, this similarity in the oxygen scarcity suggests that hypobaric hypoxia, and other common factors between these two conditions, could be involved in the aggravation of the pathological prostatic status. However, there is still a lack of evidence in the association of this disease in males at high altitudes. This review aims to examine the possible mechanisms that hypobaric hypoxia might negatively add to the pathological prostate function in males who live and work at high altitudes. More profound investigations of hypobaric hypoxia's direct action on the prostate could help understand this exposure's effect and prevent worse prostate illness impact in males at high altitudes.


Subject(s)
Altitude Sickness , Altitude , Altitude Sickness/complications , Humans , Hypoxia , Male , Oxygen , Prostate , Reproduction
11.
J Fungi (Basel) ; 9(1)2022 Dec 28.
Article in English | MEDLINE | ID: mdl-36675868

ABSTRACT

Frosty pod rot, caused by Moniliophthora roreri, is the most damaging disease of cacao in Latin America and, to better comprehend its epidemiology, we must understand its dissemination and proliferation. However, we do not know how M. roreri spores loads fluctuate in time and space due to the lack of a reliable technique to quantify M. roreri spores in the fields. Therefore, we developed a method that relies on spore traps and qPCR to detect and quantify M. roreri spore loads. This study demonstrated that the qPCR protocol can detect down to 0.025 ng of M. roreri DNA and quantify between 0.006 ng and 60 ng. Moreover, it demonstrated that qPCR protocol can detect and quantify DNA extracted from spore suspension and spore traps containing at least 2.9 × 104 M. roreri spores. However, the variability of the estimates for spore samples was high. Finally, we described a spore-trap device designed to carry spore traps in the field. The qPCR protocol and spore-trap device here developed will help in the understanding of the M. roreri dissemination patterns since they can be used to assess the environmental loads of M. roreri spore in cacao fields.

12.
13.
Environ Epidemiol ; 5(6): e179, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34909559

ABSTRACT

BACKGROUND: We have previously documented an inverse relationship between PM2.5 in Lima, Peru, and reproductive outcomes. Here, we investigate the effect of temperature on birth weight, birth weight-Z-score adjusted for gestational age, low birth weight, and preterm birth. We also explore interactions between PM2.5 and temperature. METHODS: We studied 123,034 singleton births in three public hospitals of Lima with temperature and PM2.5 during gestation between 2012 and 2016. We used linear, logistic, and Cox regression to estimate associations between temperature during gestation and birth outcomes and explored possible modification of the temperature effect by PM2.5. RESULTS: Exposure to maximum temperature in the last trimester was inversely associated with both birth weight [ß: -23.7; 95% confidence interval [CI]: -28.0, -19.5] and z-score weight-for-gestational-age (ß: -0.024; 95% CI: -0.029, -0.020) with an interquartile range of 5.32 °C. There was also an increased risk of preterm birth with higher temperature (interquartile range) in the first trimester (hazard ratio: 1.04; 95% CI: 1.001, 1.070). The effect of temperature on birthweight was primarily seen at higher PM2.5 levels. There were no statistically significant associations between temperature exposure with low birth weight. CONCLUSIONS: Exposition to maximum temperature was associated with lower birth weight and z-score weight-for-gestational-age and higher risk of preterm birth, in accordance with much of the literature. The effects on birth weight were seen only in the third trimester.

15.
Ann Work Expo Health ; 65(8): 908-918, 2021 10 09.
Article in English | MEDLINE | ID: mdl-34435202

ABSTRACT

OBJECTIVES: This study aims to assess the health effects on mining workers of exposure to chronic intermittent hypoxia (CIH) at high- and very high-altitude mining compared with similar work at lower altitudes in Chile, and it also aims to constitute the baseline of a 5-year follow-up study. METHODS: We designed a cross-sectional study to assess health conditions in 483 miners working at 2 levels of altitude exposure: 336 working at a very high or high altitude (HA; 247 above 3900-4400 m, and 89 at 3000-3900 m), and 147 below 2400 m. Subjects were randomly selected in two stages. First, a selection of mines from a census of mines in each altitude stratum was made. Secondly, workers with less than 2 years of employment at each of the selected mines were recruited. The main outcomes measured at the baseline were mountain sickness, sleep alterations, hypertension, body mass index, and neurocognitive functions. RESULTS: Prevalence of acute mountain sickness (AMS) was 28.4% in the very high-altitude stratum (P = 0.0001 compared with the low stratum), and 71.7% experienced sleep disturbance (P = 0.02). The adjusted odds ratio for AMS was 9.2 (95% confidence interval: 5.2-16.3) when compared with the very high- and low-altitude groups. Motor processing speed and spatial working memory score were lower for the high-altitude group. Hypertension was lower in the highest-altitude subjects, which may be attributed to preoccupational screening even though this was not statistically significant. CONCLUSIONS: Despite longer periods of acclimatization to CIH, subjects continue to present AMS and sleep disturbance. Compromise of executive functions was detected, including working memory at HA. Further rigorous research is warranted to understand long-term health impacts of high-altitude mining, and to provide evidence-based policy recommendations.


Subject(s)
Altitude Sickness , Occupational Exposure , Altitude , Altitude Sickness/epidemiology , Chile/epidemiology , Cross-Sectional Studies , Follow-Up Studies , Humans , Hypoxia/epidemiology , Longitudinal Studies
16.
ACS Sens ; 6(6): 2136-2140, 2021 06 25.
Article in English | MEDLINE | ID: mdl-34047541

ABSTRACT

Serological tests are crucial in a pandemic scenario, since they are a valuable tool to spot those citizens with potential immunity, specific regions with herd immunity or particular at-risk populations, as well as acquired immunity after vaccination. Hence, high-throughput, fast, cost-effective, and straightforward technologies facilitating interrogation of COVID-19 seroconversion are an existing need. Herein, we developed an innovative assay for the determination of COVID-19 seroconversion. Fluorophore-labeled SARS-CoV-2 spike receptor-binding domain recombinant protein (F-RBD) was discovered to operate as a bioprobe that emits a strong fluorescence upon COVID-19 antibody detection; however, F-RBD fluorescence was deactivated by graphene oxide-decorated surfaces when COVID-19 antibodies are absent in the sample. With a cost of less than 0.5 USD per test (at laboratory scale), the biosensing system offers optimum results within 42 min. To demonstrate that this technology is technically sound in a relevant environment, 34 human serum samples were analyzed and clearly differentiated, requiring a tiny amount of serum (1 µL to be later diluted in saline buffer).


Subject(s)
COVID-19 , Antibodies, Viral , Energy Transfer , Humans , SARS-CoV-2 , Seroconversion
17.
Occup Environ Med ; 78(10): 753-760, 2021 10.
Article in English | MEDLINE | ID: mdl-33980699

ABSTRACT

OBJECTIVE: The aim was to determine the effects of chronic intermittent hypobaric hypoxia (CIHH) on prostate-specific antigen (PSA) levels in Chilean miners who work at different altitudes. METHODS: A cross-sectional study was conducted between April and July 2019. Miners from five mines (N=338) at different altitudes were evaluated. We recorded sociodemographic, working and altitude information. Haemoglobin oxygen saturation (SaO2) and haemoglobin (Hb) were measured in situ, while PSA and testosterone were analysed at a low level. Linear mixed-effect models were used to evaluate the association between PSA level and two CIHH exposures: composite CIHH (with four descriptors) and ChileStd-CIHH (CIHH Chilean standard; based on the Chilean technical guide for occupational exposure to CIHH). All models were adjusted by age, body mass index and day of the work the samples were taken. RESULTS: Highest and lowest PSA levels were found in mines ≥3000 m above sea level (mine 3: median=0.75, IQR=-0.45; mine 4: median=0.46, IQR=-0.35). In the multilevel models, the wider altitude difference between mining operation and camp showed lower PSA levels (model D: ßPSA=-0.93 ng/mL, ßlogPSA=-0.07, p<0001), adjusted for other CIHH descriptors, SaO2, Hb and testosterone. The descriptors of composite CIHH explained better PSA variations than ChileStd-CIHH (model D: marginal R2=0.090 vs model A: marginal R2=0.016). CONCLUSIONS: Occupational health regulations and high altitude medicine should consider these results as initial evidence on the inclusion of new descriptors for CIHH and the possible effect of this exposure on PSA levels in this male-dominated occupational sector.


Subject(s)
Altitude Sickness/complications , Miners/statistics & numerical data , Occupational Diseases/etiology , Prostate-Specific Antigen/blood , Adult , Altitude Sickness/epidemiology , Altitude Sickness/etiology , Chile/epidemiology , Cross-Sectional Studies , Hemoglobins/analysis , Humans , Male , Middle Aged , Mining/statistics & numerical data , Occupational Diseases/epidemiology , Oxygen/blood , Young Adult
18.
Sci Rep ; 11(1): 2344, 2021 01 27.
Article in English | MEDLINE | ID: mdl-33504825

ABSTRACT

Soil respiration from agricultural soils is a major anthropogenic source of CO2 to the atmosphere. With-in season emission of soil CO2 from croplands are affected by changes in weather, tillage, plant row spacing, and plant growth stage. Tillage involves physical turning of soils which accelerate residue decomposition and CO2 emission. No-tillage lacks soil disturbance and residues undergo slower decomposition at the surface. In this study, we compared with-in season soil conditions (temperature and moisture) and soil respiration from two major crops (soybean and winter wheat) by making high temporal frequency measurements using automated chambers at half-hourly intervals. The experiment lasted for 179 days. Total number of measurements made from conventional and no-tillage soybean and winter wheat plots were 6480 and 4456, respectively. Average flux after the winter-dormancy period of wheat was 37% higher in tilled soil compared to no-till soil. However, average flux during the soybean growing season was 8% lower in conventional till compared to no-till soil. This differential response of soil respiration in wheat and soybean was primarily due to tillage-induced changes in surface characteristics (residue cover) and soil environmental conditions (soil temperature and soil moisture). Results from this study can help elucidate relationships for modeling and assessment of field-scale soil CO2 emissions from dryland wheat and soybean crops grown in sub-tropics.


Subject(s)
Glycine max/chemistry , Soil/chemistry , Triticum/chemistry , Agriculture , Carbon Dioxide/chemistry , Crops, Agricultural/chemistry , Environmental Monitoring , Seasons
19.
Microorganisms ; 8(10)2020 10 06.
Article in English | MEDLINE | ID: mdl-33036191

ABSTRACT

The widely conserved Csr/Rsm (carbon storage regulator/repressor of stationary-phase metabolites) post-transcriptional regulatory system controls diverse phenotypes involved in bacterial pathogenicity and virulence. Here we show that Pseudomonas amygdali pv. phaseolicola 1448A contains seven rsm genes, four of which are chromosomal. In RNAseq analyses, only rsmE was thermoregulated, with increased expression at 18 °C, whereas the antagonistic sRNAs rsmX1, rsmX4, rsmX5 and rsmZ showed increased levels at 28 °C. Only double rsmA-rsmE mutants showed significantly altered phenotypes in functional analyses, being impaired for symptom elicitation in bean, including in planta growth, and for induction of the hypersensitive response in tobacco. Double mutants were also non-motile and were compromised for the utilization of different carbon sources. These phenotypes were accompanied by reduced mRNA levels of the type III secretion system regulatory genes hrpL and hrpA, and the flagellin gene, fliC. Biosynthesis of the phytotoxin phaseolotoxin by mutants in rsmA and rsmE was delayed, occurring only in older cultures, indicating that these rsm homologues act as inductors of toxin synthesis. Therefore, genes rsmA and rsmE act redundantly, although with a degree of specialization, to positively regulate diverse phenotypes involved in niche colonization. Additionally, our results suggest the existence of a regulatory molecule different from the Rsm proteins and dependent on the GacS/GacA (global activator of antibiotic and cyanide production) system, which causes the repression of phaseolotoxin biosynthesis at high temperatures.

20.
Biosens Bioelectron ; 165: 112319, 2020 Oct 01.
Article in English | MEDLINE | ID: mdl-32729472

ABSTRACT

Immunoassays are fundamental analytical tools in molecular diagnostics, therapy monitoring and drug discovery. Nevertheless, they often take around 6 h and require cumbersome procedures. We introduce a breakthrough in immunosensing based on the photoluminescence quenching capabilities of graphene oxide (GO) and the versatile format offered by the famous microwell plates. Taking advantage of the highly efficient non-radiative energy transfer occurring between photoexcited fluorophores (donors) and GO (acceptor), we discovered that flurophore-labelled antibodies (Fl-Abs) are quickly and strongly quenched by the studied GO-coated microwell, whereas Fl-Abs complexed with the respective analyte are weakly quenched by the same surface due to the low affinity between the GO-coated surface and the relatively long distance between these photoluminescent complexes and the GO-coated surface. In doing so, we developed a conceptually innovative single-step immunosensing platform, avoiding blocking, separation and washing steps and exploiting a single antibody. Importantly, the biosensing response can be interrogated in real time. This leads to an advantageous immunodetection phenomenon which is observable in few minutes (e.g. 5 min). The resulting highly transformative biosensing platform operates with different photoluminescent agents and different analytes. Besides, this biosensing platform was demonstrated to operate with real samples of human urine doped with different concentrations of prostate specific antigen.


Subject(s)
Biosensing Techniques , Graphite , Humans , Immunoassay , Oxides
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