This paper assesses the magnitude of Pb uptake in cortical and trabecular bones in healthy animals and animals with altered balance in bone turnover, and the impact of exposure to Pb on serum markers ...of bone formation and resorption. The results reported herein provide physiological evidence that Pb distributes differently in central compartments in Pb metabolism, such as cortical and trabecular bones, in healthy animals and animals with altered balance in bone turnover, and that exposure to Pb does have an impact on bone resorption resulting in OC-dependent osteopenia. These findings show that Pb may play a role in the etiology of osteoporosis and that its concentration in bones varies as a result of altered bone turnover characteristic of this disease, a long standing question in the field. In addition, data collected in this study are consistent with previous observations of increased half-life of Pb in bone at higher exposures. This evidence is relevant for the necessary revision of current physiologically based kinetic models for Pb in humans.
Variant histone H3.3 is incorporated into nucleosomes by a mechanism that does not require DNA replication and has also been implicated as a potential mediator of epigenetic memory of active ...transcriptional states. In this study, we have used chromatin immunoprecipitation analysis to show that H3.3 is found mainly at the promoters of transcriptionally active genes. We also show that H3.3 combines with H3 acetylation and K4 methylation to form a stable mark that persists during mitosis. Our results suggest that H3.3 is deposited principally through the action of chromatin‐remodelling complexes associated with transcriptional initiation, with deposition mediated by RNA polymerase II elongation having only a minor role.
Residual waters vs. multiresistant bacteria Joadas, Andreia; Nicolau, Bruno; Maia e Silva, Alexandra ...
Annals of medicine (Helsinki),
01/2024, Letnik:
51, Številka:
sup1
Journal Article
Recenzirano
Odprti dostop
Introduction: Water is used daily in numerous domestic and industrial activities, and when discarded is considered wastewater. The self-medication, antibiotics inappropriate prescription, and the use ...of antibiotics in animal feed, leads to the environment being a reservoir of bacteria carrying resistance genes, allowing their dissemination among bacterial communities of water and soil. Bacteria can have several associated resistance mechanisms, giving them the ability to be resistant to different classes of antibiotics. The 3rd generation cephalosporins have an extended action spectrum and are hydrolyzed by the extended spectrum β-lactamases (ESBLs). The same bacterium can express these enzymes associated with an acetyltransferase encoded by the aac (6')-Ib-cr gene, which confers resistance to aminoglycosides (amikacin and tobramycin) and simultaneously to Fluorquinolones.
Objective: Identification of resistant genes in wastewater isolates.
Materials and methods: 164 isolates from the residual water, were studied for antibiotic susceptibility and 144 were selected for identification of resistance genes by PCR reaction and sequencing.
Results: The antimicrobial study of 144 strains, showed that 78% (112/144) were resistant to ciprofloxacin. The resistance to ciprofloxacin was studied by the detection of aac (6')-Ib-cr gene, found in 26% (37/144). The remained resistant isolates could have different mechanisms, such as qnr genes plasmid-mediated quinolone resistance and/or mutations on chromosomal genes (gyrA and parC). Among the 3rd generation cephalosporin resistance, were found 35% (50/114) were found resistant to cefotaxime and 26% (37/144) to ceftazidime. After sequencing, the following enzymes were predominant: CTX-M-15 (17/55); CTX-M-14 (6/55). The enzymes CTX-M-1, CTX-M-2, CTX-M-98 were found one by each isolate.
Conclusion: The existence of bacteria with resistance genes to 3rd generation cephalosporins simultaneously with fluoroquinolones and aminoglycosides constitutes a serious public health problem, with the aggravation of having the same susceptibility profile and the same genetic identity of the hospital strains.
Introduction: Nowadays, bacterial resistance to antibiotics is a problem that has been growing in Portugal, Europe and all around the world, with its cause being in the uncontrolled use of ...antibiotics and the dissemination of resistance genes among different bacteria through nature.
Objective: Identification of resistant genes inserted into Class I Integrons in wastewater isolates
Materials and methods: 165 isolates (110 from affluent waters and 55 from effluent waters) were studied for antibiotic susceptibility and 101 isolates (63 from affluent and 38 from effluent waters) were selected for screening and identification of resistance genes by PCR reaction and sequencing, using 5'-CS and 3'-CS oligonucleotides as specific primers for conserved segments of Class I Integrons.
Results: From residual water analyses the total of 165 isolates were multiresistant to antibiotics used in hospital and ambulatory clinics. Among these isolates, the resistance to Trimethroprim-Sulfamethoxazole and Gentamicin were 61,2% (101/165) and 46.1% (76/165), respectively. Electrophoresis revealed DNA fragments with sizes ranging from 500 to 2000 base pairs according to the number of genes inserted in Integron. After analysis of sequences were identified 22 genes dfr-type (dfrA1, dfrA12, dfrA15, dfrA17 and dfrA27) responsible by resistance to Trimethroprim, These genes were found in 14 isolates from affluent and 7 from effluent waters. Also, the resistance to gentamicin were conferred by 19 genes aad-type (aadA1, aadA2 and aadA5) from 12 affluent and 7 effluent isolates. These genes can be found alone or in association with each other in the same Integron. Other genes that confer resistance to other antibiotics have also been found such as: rifampicin (arr-3); β-lactamics (oxa-2) and gene aac(6')-Ib-cr which simultaneously confer resistance to fluorquinolones and aminoglycosides only in isolates from affluent waters.
Conclusion: The residual waters, upon arriving at urban wastewater treatment plant, are subjected to a depuration process to eliminate chemical and biological contaminants. However, our study revealed the presence of multiresistant bacteria in effluents, which allows their dissemination in the environment and its impact on public health.
Introduction: Prostate cancer is one of most frequent neoplasia in males, affecting the majority of men in the eighth decade of life. It is not yet known what specifically causes prostate cancer, but ...there are several risk factors for the disease, including age or diet, and it is known that different populations have different risk of developing this cancer. For instance, men in developed countries have higher risk to get this neoplasia and mortality rate is higher in black men, according International Agency for Research on Cancer 2012 data. Prostate cancer can often be detected before symptoms start by testing the amount of prostate-specific antigen (PSA) and is variant forms in a man's blood. However, high levels of this protein do not mean malignancy. So, new biomarkers of this cancer are need. In order to learn more about prostate cancer, we aim to analyze the frequency of ARE-I polymorphism at -158 position of the KLK3 gene in prostatic tissue and the results were compared with other populations frequencies it was done the analysis of the ARE-I polymorphism at -158 position of the KLK3 gene in prostatic tissue and the results were compared with other populations frequencies
1
.
Materials and methods: In this study it was analysed the rs266882 polymorphism at - 158 position of the KLK3 gene in prostatic tissue from 96 Portuguese individuals diagnosed with prostate cancer and individuals with benign prostatic hyperplasia, from Anatomy Pathology Department of CHBM.The study protocol was previously approved by the hospital ethics committee. PCR-RFLP analysis was performed in DNA extracted from paraffin embedded tissue sections. The allelic and genotype frequencies were analysed and calculated by Hardy-Weinberg R package based on χ
2
-test, with a 95% CI and the results were compared with other ethnic populations from Ensembl Project using a χ
2
test.
Results: Samples from the same individual showed the same genotype in cancer and normal tissue, and the genotype found were 48 cases of AA (50%), 35 of AG (36.5%) and 13 GG (13.5%). All frequencies were in Hardy-Weinberg equilibrium (p = 0.119), with allelic frequency of 68,2% for A and 31.8% for G, being significantly different from African (p < 0.016), European (p < 0.0003), American, South and East Asian (p < 0.0001) population. Obtained genotype frequencies were more comparable to African population (p < 0.0004) than the others ethnic groups. No statistically significant association was showed between genotype and diagnosis. As reported previously
2
, the result of the association between genotype and the T of tumour stage was nearly statistically significant (p-value = 0.08), and the presence of the A allele showed a statistically significant association with T (p-value = 0.046) but not the G allele.
Discussion and conclusions: The allelic and genotype frequencies are closer to the African than European or Asian population, but it wasńt confirm by statistical tests. The African population does not present significant differences from our population to the level of 0.01 for the allelic frequency. The presence of the A allele showed a statistically significant association with T of stage tumor. PSA levels were associated with the tumor volume.
Peroxisome Proliferator-Activated Receptors (PPAR) are transcription factors suggested to be involved in inflammatory lesions of autoimmune encephalomyelitis and multiple sclerosis (MS). Our ...objective was to assess whether Natalizumab (NTZ) therapy is associated with alterations of PPAR expression in MS patients. We analyzed gene expression of PPAR in peripheral blood mononuclear cells (PBMC) as well as blood inflammatory markers in women with MS previously medicated with first-line immunomodulators (baseline) and after NTZ therapy. No differences in PPARα, PPARβ/δ, PPARγ, and CD36 mRNA expression were found in PBMC between patients under baseline and healthy controls. At three months, NTZ increased PPARβ/δ mRNA (p=0.009) in comparison to baseline, while mRNA expression of PPARγ and CD36 (a well-known PPAR target gene) was lower in comparison to healthy controls (p=0.026 and p=0.028, resp.). Although these trends of alterations remain after six months of therapy, the results were not statistically significant. Osteopontin levels were elevated in patients (p=0.002) and did not change during the follow-up period of NTZ treatment. These results suggest that PPAR-mediated processes may contribute to the mechanisms of action of NTZ therapy.
While in some countries, the possession of psychoactive substances leads to prison sentences or execution, other countries, like Portugal, follow an avenue leading to a drug-tolerant culture. ...However, there is a lack of empirical data on Portuguese populations to measure the drug-use trend. The present study uses multidisciplinary approaches to explore the prevalence of alcohol and drug consumption on a Portuguese student population (N = 81, ages ranged from 17 to 40 years), associating it with psychological and genetic factors. The results show a prevalence of cannabis consumption higher than what is reported by the EMCDDA, and suggests that carriers of the minor allele of 5-HTTLPR have a higher propensity for addiction.
Objective: The present experiment analyzed the effects of playing a violent video game on player's sensitivity to victimized people by measuring the involuntary pupil dilation responses (PDRs) during ...a passive picture viewing paradigm and examining the mediating role of PDR on aggression. Method: Participants (N = 135) were randomly assigned to play a violent video game or a nonviolent video game. The participants' PDRs were then recorded while they were exposed to pictures of alleged victims of violence displayed in negative, neutral, and positive contexts. A competitive reaction time task was also used to measure aggression. Results: Participants in the violent game condition demonstrated both a lower PDR to the victims of violence in a negative circumstances and greater aggression than participants in the nonviolent game condition. Lower PDR to victims displayed in negative context mediated the relationship between violent game play and aggression. Conclusion: The negative effects of playing violent games are a societal concern. Our results indicate that a single violent gaming session can reduce the player's involuntary PDRs to pictures of victimized people in negative context and increase participant aggression, a new relevant finding that should encourage further research in this area.
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