25 research outputs found
Assessment of freshwater scarcity using a model based on supply and demand law
The main goal of this work is to provide an analysis methodology for assessment of water scarcity
problems based on supply and demand. To this end, we must first determine what can be considered
as supply and demand in the water scarcity problem. Although some variables involved are
physical, economical or demographical, in our approach social factors are also included. This leads
us to objectify water demand standards in relation to acceptable welfare levels. Within this
approach, water scarcity will appear when demand reaches a higher value than supply. Two supply
levels are defined based on other works. Demand is calculated within several scenarios. These
scenarios represent the outcome of political or management decisions taken to reach a welfare
standard. A special scenario will represent, simply, the continuation of the current state of affairs.
The variables needed to calculate demand are obtained through a multilevel model where the lowest
level is formed by disciplinary models and the highest level takes into account social and political
factors. The methodology is applied to the countries of the gulf of Guinea. Its application to Côte
d’Ivoire is described in detail and results are given for the other eight countries of the area. To
summarize the results, two indexes are suggested. With this methodology, it is possible to divide the
region of the gulf of Guinea in three areas of different freshwater capacity, giving new insight with
regards previous studies that did not state differences between the countries of the region.Preprin
Relationship Between Biofilm Formation and Antimicrobial Resistance in Gram-Negative Bacteria
Gram-negative microorganisms are a significant cause of
infection in both community and nosocomial settings. The
increase, emergence, and spread of antimicrobial resistance
among bacteria are the most important health problems worldwide.
One of the mechanisms of resistance used by bacteria is biofilm
formation, which is also a mechanism of virulence. This study
analyzed the possible relationship between antimicrobial
resistance and biofilm formation among isolates of three
Gram-negative bacteria species. Several relationships were found
between the ability to form biofilm and antimicrobial
resistance, being different for each species. Indeed, gentamicin
and ceftazidime resistance was related to biofilm formation in
Escherichia coli, piperacillin/tazobactam, and colistin in
Klebsiella pneumoniae, and ciprofloxacin in Pseudomonas
aeruginosa. However, no relationship was observed between global
resistance or multidrug-resistance and biofilm formation. In
addition, compared with other reported data, the isolates in the
present study showed higher rates of antimicrobial resistance.
In conclusion, the acquisition of specific antimicrobial
resistance can compromise or enhance biofilm formation in
several species of Gram-negative bacteria. However,
multidrug-resistant isolates do not show a trend to being
greater biofilm producers than non-multiresistant isolates
ETV5 i RUNX1, nous factors de transcripció implicats en la invasió miometrial del carcinoma endometrial
Actualment, en càncer d'endometri, està àmpliament acceptat el model dualístic que, atenent
a bases morfològiques, diferencia tumors de tipus i o endometrioides dels de tipus ii o
no endometrioides. La genètica molecular ha aportat dades que donen suport a aquest model
dualístic de la tumorigènesi endometrial i algunes claus per a poder especular sobre la seqüència
temporal de les alteracions moleculars que defineixen les rutes tumorigèniques. En els
càncers endometrials endometrioides, o de tipus i, es coneixen alteracions majors, com poden
ser el silenciament del gen PTEN, la inestabilitat de microsatèll. its associada a defectes en els
gens reparadors de DNA, o mutacions al gen K-ras. Aquestes alteracions defineixen la progressió
de l'endometri normal cap a la hiperplàsia i posteriorment cap al carcinoma. Recentment,
l'ús de la tecnologia de microxips de cDNA per a identificar les diferències en els patrons d'expressió
gènica entre els diferents tipus histològics de càncer d'endometri han permès la identificació
de gens expressats diferencialment que podrien ajudar-nos a entendre les diferències
en la biologia i el pronòstic clínic dels diferents histiotips tumorals. En el nostre laboratori hem
aïllat i caracteritzat dos nous factors de transcripció, ETV5 i RUNX1, que estan associats amb
els passos inicials de la infiltració miometrial en el càncer d'endometri endometrioide. Aquests
estudis, i els d'altres gens implicats en el control de la mitosi com a mecanisme major de carcinogènesi
en els càncers d'endometri no endometrioides, representen exemples de la utilitat
dels estudis genètics amplis per a comprendre el procés de tumorigènesi i les rutes implicades
en la patogènesi molecular del càncer d'endometri.A dualistic model, which has been established on a morphological basis and that differentiates
type i endometrioid from type ii non-endometrioid endometrial cancer, is widely accepted.
Molecular genetics have provided us with data supporting the dualistic model of endometrial
tumorigenesis and with some clues to speculate about the sequence of the molecular alterations
defining the tumorigenesis pathways. In type i endometrioid endometrial cancer, PTEN gene
silencing, microsatellite instability associated with defects in DNA mismatch repair genes, or
mutations in the K-ras gene are the known major alterations defining the progression from
normal endometrium to hyperplasia and then on to carcinoma. Recently, cDNA microarray
technology for identifying the differences in gene expression patterns between the histological
types of endometrial cancer have permitted the identification of differentially expressed genes
that could help us to understand differences in the biology and the clinical outcome between
histiotypes. In our laboratory, we have recently isolated and characterized two new transcription
factors, ETV5 and RUNX1, which expression appears to be associated with initial steps
of myometrial infiltration in endometrioid endometrial carcinoma. These studies, as well as
those on other genes involved in the mitotic checkpoint as a major mechanism of carcinogenesis
in non-endometrioid endometrial cancer, represent examples of how useful large genetic
screenings can be for understanding the tumorigenesis process and the future directions in the
molecular pathogenesis of endometrial cancer
Molecular markers of endometrial carcinoma detected in uterine aspirates.
Endometrial cancer (EC) is the most frequent of the invasive tumors of the female genital tract. Although usually detected in its initial stages, a 20% of the patients present with advanced disease. To date, no characterized molecular marker has been validated for the diagnosis of EC. In addition, new methods for prognosis and classification of EC are needed to combat this deadly disease. We thus aimed to identify new molecular markers of EC and to evaluate their validity on endometrial aspirates. Gene expression screening on 52 carcinoma samples and series of real-time quantitative PCR validation on 19 paired carcinomas and normal tissue samples and on 50 carcinoma and noncarcinoma uterine aspirates were performed to identify and validate potential biomarkers of EC. Candidate markers were further confirmed at the protein level by immunohistochemistry and Western blot. We identified ACAA1, AP1M2, CGN, DDR1, EPS8L2, FASTKD1, GMIP, IKBKE, P2RX4, P4HB, PHKG2, PPFIBP2, PPP1R16A, RASSF7, RNF183, SIRT6, TJP3, EFEMP2, SOCS2 and DCN as differentially expressed in ECs. Furthermore, the differential expression of these biomarkers in primary endometrial tumors is correlated to their expression level in corresponding uterine fluid samples. Finally, these biomarkers significantly identified EC with area under the receiver-operating-characteristic values ranging from 0.74 to 0.95 in uterine aspirates. Interestingly, analogous values were found among initial stages. We present the discovery of molecular biomarkers of EC and describe their utility in uterine aspirates. These findings represent the basis for the development of a highly sensitive and specific minimally invasive method for screening ECs
The up-regulation profiles of p21 WAF1/CIP1 and RUNX1/AML1 correlate with myometrial infiltration in endometrioid endometrial carcinoma
Summary We have recently described RUNX1/AML1 up-regulation in endometrioid endometrial carcinoma (EEC), proposing that it could play a role during the initial steps of myometrial infiltration. Some cell cycle regulators, including the cyclin-dependent kinase inhibitor p21 WAF1/CIP1 , have been described as targets of RUNX1/AML1. In this study, we have attempted to address the question of whether RUNX1/AML1, acting both as a gene transcription activator and a repressor, depending on the context, can be correlated with the expression of p21 WAF1/CIP1 in gynecologic malignancies, in particular in EEC, where the role of p21 WAF1/CIP1 remains controversial. Toward this end, we analyzed p21 WAF1/CIP1 expression in a large panel of EEC samples using real-time quantitative polymerase chain reaction and tissue microarray immunohistochemistry, and evaluated the extent to which RUNX1/AML1 and p21 WAF1/CIP1 interacted in the EEC samples. The strong correlation found between RUNX1/AML1 and p21 WAF1/CIP1 suggested cooperation between the 2 genes in EEC, especially in those tumor samples corresponding to stage IC carcinomas, infiltrating more than 50% of the myometrium. We hypothesize that p21 WAF1/CIP1 and RUNX1/AML1 interact during the initial steps o
The EMT signaling pathways in endometrial carcinoma
Endometrial cancer (EC) is the most common gynecologic malignancy of the female genital tract and the fourth most common neoplasia in women. In EC, myometrial invasion is considered one of the most important prognostic factors. For this process to occur, epithelial tumor cells need to undergo an epithelial to mesenchymal transition (EMT), either transiently or stably, and to differing degrees. This process has been extensively described in other types of cancer but has been poorly studied in EC. In this review, several features of EMT and the main molecular pathways responsible for triggering this process are investigated in relation to EC. The most common hallmarks of EMT have been found in EC, either at the level of E-cadherin loss or at the induction of its repressors, as well as other molecular alterations consistent with the mesenchymal phenotype-like L1CAM and BMI-1 up-regulation. Pathways including progesterone receptor, TGFβ, ETV5 and microRNAs are deeply related to the EMT process in EC
Assessment of freshwater scarcity using a model based on supply and demand law
The main goal of this work is to provide an analysis methodology for assessment of water scarcity
problems based on supply and demand. To this end, we must first determine what can be considered
as supply and demand in the water scarcity problem. Although some variables involved are
physical, economical or demographical, in our approach social factors are also included. This leads
us to objectify water demand standards in relation to acceptable welfare levels. Within this
approach, water scarcity will appear when demand reaches a higher value than supply. Two supply
levels are defined based on other works. Demand is calculated within several scenarios. These
scenarios represent the outcome of political or management decisions taken to reach a welfare
standard. A special scenario will represent, simply, the continuation of the current state of affairs.
The variables needed to calculate demand are obtained through a multilevel model where the lowest
level is formed by disciplinary models and the highest level takes into account social and political
factors. The methodology is applied to the countries of the gulf of Guinea. Its application to Côte
d’Ivoire is described in detail and results are given for the other eight countries of the area. To
summarize the results, two indexes are suggested. With this methodology, it is possible to divide the
region of the gulf of Guinea in three areas of different freshwater capacity, giving new insight with
regards previous studies that did not state differences between the countries of the region
Assessment of freshwater scarcity using a model based on supply and demand law
The main goal of this work is to provide an analysis methodology for assessment of water scarcity
problems based on supply and demand. To this end, we must first determine what can be considered
as supply and demand in the water scarcity problem. Although some variables involved are
physical, economical or demographical, in our approach social factors are also included. This leads
us to objectify water demand standards in relation to acceptable welfare levels. Within this
approach, water scarcity will appear when demand reaches a higher value than supply. Two supply
levels are defined based on other works. Demand is calculated within several scenarios. These
scenarios represent the outcome of political or management decisions taken to reach a welfare
standard. A special scenario will represent, simply, the continuation of the current state of affairs.
The variables needed to calculate demand are obtained through a multilevel model where the lowest
level is formed by disciplinary models and the highest level takes into account social and political
factors. The methodology is applied to the countries of the gulf of Guinea. Its application to Côte
d’Ivoire is described in detail and results are given for the other eight countries of the area. To
summarize the results, two indexes are suggested. With this methodology, it is possible to divide the
region of the gulf of Guinea in three areas of different freshwater capacity, giving new insight with
regards previous studies that did not state differences between the countries of the region
Relationship Between Biofilm Formation and Antimicrobial Resistance in Gram-Negative Bacteria
Gram-negative microorganisms are a significant cause of
infection in both community and nosocomial settings. The
increase, emergence, and spread of antimicrobial resistance
among bacteria are the most important health problems worldwide.
One of the mechanisms of resistance used by bacteria is biofilm
formation, which is also a mechanism of virulence. This study
analyzed the possible relationship between antimicrobial
resistance and biofilm formation among isolates of three
Gram-negative bacteria species. Several relationships were found
between the ability to form biofilm and antimicrobial
resistance, being different for each species. Indeed, gentamicin
and ceftazidime resistance was related to biofilm formation in
Escherichia coli, piperacillin/tazobactam, and colistin in
Klebsiella pneumoniae, and ciprofloxacin in Pseudomonas
aeruginosa. However, no relationship was observed between global
resistance or multidrug-resistance and biofilm formation. In
addition, compared with other reported data, the isolates in the
present study showed higher rates of antimicrobial resistance.
In conclusion, the acquisition of specific antimicrobial
resistance can compromise or enhance biofilm formation in
several species of Gram-negative bacteria. However,
multidrug-resistant isolates do not show a trend to being
greater biofilm producers than non-multiresistant isolates