234 research outputs found
A small non‐coding rna modulates expression of pilus‐1 type in streptococcus pneumoniae
Streptococcus pneumoniae is a major cause of morbidity and mortality worldwide, and about 30% of the pneumococcal clinical isolates show type I pili‐like structures. These long protein-aceous polymers extending from the bacterial surface are encoded by pilus islet 1 and play major roles in adhesion and host colonization. Pili expression is bistable and is controlled by the transcriptional activator RlrA. In this work, we demonstrate that the previously identified small noncoding RNA srn135 also participates in pilus regulation. Our findings show that srn135 is generated upon processing of the 5′‐UTR region of rrgA messenger and its deletion prevents the synthesis of RrgA, the main pili adhesin. Moreover, overexpression of srn135 increases the expression of all pili genes and rises the percentage of piliated bacteria within a clonal population. This regulation is mediated by the stabilization of rlrA mRNA since higher levels of srn135 increase its half‐life to 165%. Our findings suggest that srn135 has a dual role in pilus expression acting both in cis‐ (on the RrgA levels) and in trans‐ (modulating the levels of RlrA) and contributes to the delicate balance between pili expressing and non‐expressing bacteria
Analyzing the negative effects of motivating e-learning tools in archeology teaching
[EN] In this article we study the negative effects of applying motivating e-Learning tools as a method to increase students’ engagement through their learning process. In particular, we demonstrate that increasing students’ motivation can have a negative effect on students’ efficiency if they engage with the applications in a wrong way. In our carried out experience, we have used a virtual reconstruction of the TT 209 archeological site in Luxor. This application allows students to move inside and outside the site and get some information on the different activities that were done along the field work. We have found that students tend to use the application just as a game. This fact decreases students’ efficiency since they do not pay enough attention to the learning activities inside the system. To avoid this effect, we propose to use gamification strategies such as rewards to redirect students’ attention to the learning process
Sociobiological Control of Plasmid copy number
Background:
All known mechanisms and genes responsible for the regulation of plasmid replication lie with the plasmid rather than the chromosome. It is possible therefore that there can be copy-up mutants. Copy-up mutants will have within host selective advantage. This would eventually result into instability of bacteria-plasmid association. In spite of this possibility low copy number plasmids appear to exist stably in host populations. We examined this paradox using a computer simulation model.

Model:
Our multilevel selection model assumes a wild type with tightly regulated replication to ensure low copy number. A mutant with slightly relaxed replication regulation can act as a “cheater” or “selfish” plasmid and can enjoy a greater within-host-fitness. However the host of a cheater plasmid has to pay a greater cost. As a result, in host level competition, host cell with low copy number plasmid has a greater fitness. Furthermore, another mutant that has lost the genes required for conjugation was introduced in the model. The non-conjugal mutant was assumed to undergo conjugal transfer in the presence of another conjugal plasmid in the host cell.

Results:
The simulatons showed that if the cost of carrying a plasmid was low, the copy-up mutant could drive the wild type to extinction or very low frequencies. Consequently, another mutant with a higher copy number could invade the first invader. This process could result into an increasing copy number. However above a certain copy number within-host selection was overcompensated by host level selection leading to a rock-paper-scissor (RPS) like situation. The RPS situation allowed the coexistence of high and low copy number plasmids. The non-conjugal “hypercheaters” could further arrest the copy numbers to a substantially lower level.

Conclusions:
These sociobiological interactions might explain the stability of copy numbers better than molecular mechanisms of replication regulation alone
Audiovestibular manifestations in patients with ankylosing spondylitis
Ankylosing spondylitis (AS) is a chronic inflammatory disease of unknown origin affecting up to 1% of the population. Little is known about audiovestibular impairment in patients with AS, especially the presence of cochleovestibular dysfunction in these patients. To investigate audiovestibular manifestations in AS, we studied a series of 50 consecutive patients who fulfilled the modified New York diagnostic criteria for AS and 44 matched controls. Individuals with history of cardiovascular disease, cerebrovascular complications, peripheral artery disease, renal insufficiency, syphilis, Meniere and other vestibular syndromes, infections involving the inner ear, barotrauma, or in treatment with ototoxic drugs were excluded. Most patients with AS were men (80%). The mean age at the time of study was 52.5 years, and mean age at the onset of symptoms was 34.4 years. Twenty-nine (58%) patients showed abnormal hearing loss in the audiogram compared to only 8 (18%) controls (p < 0.001). Values of audiometric tests (pure-tone average and speech reception threshold) yielded significant differences between patients and controls (p < 0.001). It is noteworthy that the audiogram shape disclosed a predominant pattern of high-frequency sensorineural hearing loss in AS patients (50%) compared to controls (18%) (p = 0.002). Also, AS patients exhibited abnormal vestibular tests more commonly than controls. AS patients had an increased frequency of head-shaking nystagmus (20%) compared to controls (0%) (p < 0.001). Moreover, patients (26%) showed a significantly increased frequency of abnormal caloric test compared to controls (0%) (p < 0.001). Finally, a significantly increased frequency of abnormal clinical test of sensory integration and balance with a predominant vestibular loss pattern was observed in patients (36%) compared to controls (5%) (p < 0.001). In conclusion, the current study demonstrates strong evidence for inner ear compromise in patients with AS
Comparative analysis of heat dissipation panels for a hybrid cooling system integrated in buildings
The use of cooling panels as heat dissipation elements integrated in buildings has been previously investigated by the authors. Those elements would be connected to the
condenser and would dissipate the heat in a passive form. Following the research, this study analyses and compares the thermal performance of two heat dissipation panels as part of a hybrid cooling system. Both panels were experimentally tested under different variables, thus
having nine scenarios for each panel. Additionally, an already validated model was applied.
The empirical results show a considerable difference between the cooling capacity among them,
doubling the daily average ratio in one scenario. The heat dissipation ratios vary between 106 and 227 W/m2
in the first case and 140 and 413 W/m2 in the second. Regarding the model
applicability, the average error for each panel was 4.0% and 8.5%. The bond between the metal sheet and the pipes of the panels has proven to be the main parameter to assure the highest heat dissipation potential of each panel
Association of occupational heat exposure and colorectal cancer in the MCC-Spain study
Objective Heat exposure and heat stress/strain is a concern for many workers. There is increasing interest in potential chronic health effects of occupational heat exposure, including cancer risk. We examined potential associations of occupational heat exposure and colorectal cancer (CRC) risk in a large Spanish multi-case- control study.Methods We analyzed data on 1198 histologically confirmed CRC cases and 2690 frequency-matched controls. The Spanish job-exposure matrix, MatEmEsp, was used to assign heat exposure estimates to the lifetime occupa-tions of participants. Three exposure indices were assessed: ever versus never exposed, cumulative exposure and duration (years). We estimated odds ratios (OR) and 95% confidence intervals (CI) using unconditional logistic regression adjusting for potential confounders.Results Overall, there was no association of ever, compared with never, occupational heat exposure and CRC (OR 1.09, 95% CI 0.92-1.29). There were also no associations observed according to categories of cumulative exposure or duration, and there was no evidence for a trend. There was no clear association of ever occupational heat exposure and CRC in analysis conducted among either men or women when analyzed separately. Positive associations were observed among women in the highest categories of cumulative exposure (OR 1.81, 95% CI 1.09-3.03) and duration (OR 2.89, 95% CI 1.50-5.59) as well as some evidence for a trend (P<0.05).Conclusion Overall, this study provides no clear evidence for an association between occupational heat exposure and CRC
One-year dietary supplementation with walnuts modifies exosomal miRNA in elderly subjects
Purpose: Epidemiological studies and clinical trials support the association of nut consumption with a lower risk of prevalent non-communicable diseases, particularly cardiovascular disease. However, the molecular mechanisms underlying nut benefits remain to be fully described. MicroRNAs (miRNAs) are post-transcriptional regulators of gene expression and play a pivotal role in health and disease. Exosomes are extracellular vesicles released from cells and mediate intercellular communication. Whether nut consumption modulates circulating miRNAs (c-miRNAs) transported in exosomes is poorly described. Methods: Cognitively healthy elderly subjects were randomized to either control (n = 110, abstaining from walnuts) or daily supplementation with walnuts (15% of their total energy, ≈30–60 g/day, n = 101) for 1-year. C-miRNAs were screened in exosomes isolated from 10 samples, before and after supplementation, and identified c-miRNA candidates were validated in the whole cohort. In addition, nanoparticle tracking analysis and lipidomics were assessed in pooled exosomes from the whole cohort. Results: Exosomal hsa-miR-32-5p and hsa-miR-29b-3p were consistently induced by walnut consumption. No major changes in exosomal lipids, nanoparticle concentration or size were found. Conclusion: Our results provide novel evidence that certain c-miRNAs transported in exosomes are modulated by walnut consumption. The extent to which this finding contributes to the benefits of walnuts deserves further research.Fundacion Ramon Areces (CIVP18A3888) Madrid, Spain; the Instituto de Salud Carlos III-Fondo de Investigacion Sanitaria–Fondo Europeo de Desarrollo Regional (grant PI15/01014 and PI18/01152), and the Spanish Agencia Estatal de Investigacion and European Feder Funds (AGL2016-78922-R, PID2019-109369RB-I00, RTI2018-093873-A-I00 and BIO2017-86500-R). AS-V is recipient of the Instituto de Salud Carlos III Miguel Servet II fellowship (grant CP II 17/00029
Sleep and breast and prostate cancer risk in the MCC-Spain study
Breast and prostate cancers have been associated with circadian disruption. Some previous studies examined associations of sleep duration and breast or prostate cancer risk though findings remain inconsistent. This study examines associations of a range of detailed sleep characteristics and breast and prostate cancer risk in a large-scale population-based case-control study, MCC-Spain. A total of 1738 incident breast cancer cases, 1112 prostate cancer cases and frequency matched controls (n = 1910, and 1493 respectively) were recruited. Detailed data on habitual sleep duration, quality, timing, and daytime napping ("siesta") were collected at recruitment. Additional data on sleep habits during both the previous year and at age 40 years were also subsequently captured. Adjusted odds ratios (ORs) and 95% confidence intervals (CI) were estimated. There were no associations of habitual sleep duration (h), timing of sleep, or any or specific sleep problems, and either breast and prostate cancer risk. There was a significant positive association of ever taking habitual siestas at recruitment and breast cancer risk (OR = 1.22, 95% CI 1.06-1.42), which strengthened with increased frequency or duration. There were also significant positive associations observed for both breast and prostate cancer, among those reporting recent sleep problems, but not sleep problems at age 40 years, in a subsequent circadian questionnaire. Adverse associations with siesta and disturbed sleep during the previous year likely reflect symptoms of developing/diagnosed cancer and comorbidities. Overall, there was no clear association between various sleep characteristics and breast or prostate cancer risk observed.Funding: The study was partially funded by the ‘Accion Transversal del Cancer’, approved by the Spanish Ministry Council on 11 October 2007, by the Instituto de Salud Carlos III-FEDER (PI08/1770, PI08/1359, PI09/00773, PI09/01286, PI09/01903, PI09/02078, PI09/01662, PI11/01403, PI11/01889, PI11/02213; PI12/00265, PI12/01270, PI12/00715, PI12/00150, PI14/01219, PI14/0613, PI15/00069, PI15/00914, PI15/01032, PI17CIII/00034, CIBERESP CB06/02/0073), the Fundación Marqués de Valdecilla (API 10/09), the Junta de Castilla y León (LE22A10- 2), the Consejería de Salud of the Junta de Andalucía (PI-0571-2009, PI-0306-2011, salud201200057018tra), the Conselleria de Sanitat of the Generalitat Valenciana (AP_061/10), the Recercaixa (2010ACUP 00310), the Regional Government of the Basque Country, the European Commission grants FOOD-CT-2006-036224-HIWATE, the Spanish Association Against Cancer (AECC) Scientifc Foundation, the Catalan Government DURSI grant 2014SGR647, 2017SGR723, 2017SGR1085 and 2014SGR850, the Fundación Caja de Ahorros de Asturias and by the University of Oviedo. MCT is funded by a Ramón y Cajal fellowship (RYC-2017-01892) from the Spanish Ministry of Science, Innovation and Universities and co-funded by the European Social Fund. ISGlobal acknowledges support from the Spanish Ministry of Science and Innovation through the “Centro de Excelencia Severo Ochoa 2019–2023” Program (CEX2018-000806-S), and support from the Generalitat de Catalunya through the CERCA Program
El hepatocarcinoma en la Comunidad Foral de Navarra: estudio de características y evolución en la práctica clínica habitual
Fundamento. El hepatocarcinoma asienta generalmente
sobre una cirrosis hepática. El cribado pretende mejorar
la supervivencia. Los objetivos de nuestro trabajo son
conocer las características del hepatocarcinoma, su evolución y la influencia del cribado en su supervivencia, en
la práctica clínica en Navarra.
Material y Métodos. Estudio prospectivo y retrospectivo de 111 pacientes diagnosticados de hepatocarcinoma
en hospitales públicos navarros, entre enero de 2009 y
enero de 2015. Se analizaron características epidemiológicas, clínicas, analíticas, radiológicas, estadio tumoral,
tratamiento y evolución, y el efecto del cribado.
Resultados. El 84,7% de los pacientes eran varones. La
edad media fue 67 años. El 85,6% tenían cirrosis. La etiología más frecuente fue la enólica (40,7%). El 62,2% se
diagnosticó en estadios tempranos, el 15,3% en intermedio y el 22,5% en avanzado o terminal. El 4,5% se trató
mediante trasplante, el 21,6% con resección, el 23,4%
mediante ablación, el 10,8% con quimioembolización,
el 5,4% con radiembolización, el 2,7% con embolización,
el 13,5% con sorafenib y el 18% de modo sintomático.
Solamente 32 pacientes (28,8%) realizaban cribado. No
se han encontrado diferencias significativas en la supervivencia según la realización de cribado (mediana de 32
y 34 meses; p = 0,971).
Conclusiones. En Navarra, el hepatocarcinoma se desarrolla generalmente sobre una cirrosis, cuya etiología
más frecuente es el consumo de alcohol. El hepatocarcinoma se ha diagnosticado con más frecuencia en estadios iniciales, fuera de cribado. El cribado no ha mejorado la supervivencia.Background. Hepatocellular carcinoma generally arises
in a cirrhotic liver. The aim of screening is to improve survival. The aims of our study are to determine the characteristics and evolution of hepatocellular carcinoma and
the effect of screening on survival, in clinical practice in
Navarre.
Methods. Prospective and retrospective study of 111 patients diagnosed with hepatocellular carcinoma in public
hospitals in Navarre between January 2009 and January
2015. Epidemiological, clinical, analytical, radiological
characteristics, tumour staging, treatment and evolution
were analyzed. Survival was compared between patients
subjected to screening and those not.
Results. Mean age was 67 years. The patients (84.7%)
were mainly male and 85.6% had cirrhosis. The most frequent aetiology was alcohol consumption (40.7%). 62.2%
were diagnosed in early stages, 15.3% in intermediate
and 22.5 % in advanced or terminal stages. 4.5% received transplants, 21.6% received surgical resection, 23.4%
were treated with ablation techniques, 10.8 % with chemoembolization, 5.4% with radiembolization, 2.7% with
embolization, 13.5 % with sorafenib and 18% symptomatically. Only 32 patients (28.8%) were subjected to screening. No statistical differences were found in survival depending on surveillance (32 month versus 34; p = 0.971).
Conclusions. In Navarre, hepatocellular carcinoma generally appears against a background of cirrhosis, and alcohol is the most frequent aetiology. Hepatocellular carcinoma is diagnosed most frequently in early stages and
out of screening practices. Screening was not associated
to better survival
Occupational Heat Exposure and Breast Cancer Risk in the MCC-Spain Study
[EN] Background: Mechanisms linking occupational heat exposure with chronic diseases have been proposed. However, evidence on occupational heat exposure and cancer risk is limited. Methods: We evaluated occupational heat exposure and female breast cancer risk in a large Spanish case-control study. We enrolled 1,738 breast cancer cases and 1,910 frequency-matched population controls. A Spanish job-exposure matrix, MatEmEsp, was used to assign estimates of the proportion of workers exposed (P >= 25% for at least 1 year) and work time with heat stress (wet bulb globe temperature ISO 7243) for each occupation. We used three exposure indices: ever versus never exposed, lifetime cumulative exposure, and duration of exposure (years). We estimated ORs and 95% confidence intervals (CI), applying a lag period of 5 years and adjusting for potential confounders. Results: Ever occupational heat exposure was associated with a moderate but statistically significant higher risk of breast cancer (OR 1.22; 95% CI, 1.01-1.46), with significant trends across categories of lifetime cumulative exposure and duration (P-trend = 0.01 and 0.03, respectively). Stronger associations were found for hormone receptor-positive disease (OR ever exposure = 1.38; 95% Cl, 1.12-1.67). We found no confounding effects from multiple other common occupational exposures; however, results attenuated with adjustment for occupational detergent exposure. Conclusions: This study provides some evidence of an association between occupational heat exposure and female breast cancer risk.SIThis study was partially funded by the “Accion Transversal del Cancer,” approved by the Spanish Ministry Council on October 11, 2007; the Instituto de Salud Carlos III-FEDER (PI08/1770, PI08/1359, PI09/00773, PI09/01286, PI09/01903, PI09/02078, PI09/01662, PI11/01403, PI11/01889, and PI12/00265); the Fundación Marqués de Valdecilla (API 10/09); the Junta de Castilla y León (LE22A10-2); the Consejería de Salud of the Junta de Andalucía (2009-S0143); the Conselleria de Sanitat of the Generalitat Valenciana (AP_061/10); the Recercaixa (2010ACUP 00310); the Regional Government of the Basque Country; the Consejería de Sanidad de la Región de Murcia; the European Commission grants FOOD-CT-2006–036224-HIWATE; the Spanish Association Against Cancer (AECC) Scientific Foundation; the Catalan Government DURSI grant 2014SGR647; the Secretariat for Universities and Research of the Ministry of Business and Knowledge of the Government of Catalonia (2017SGR1085); the Fundación Caja de Ahorros de Asturias; and the University of Oviedo. M.C. Turner is funded by a Ramón y Cajal fellowship (RYC-2017-01892) from the Spanish Ministry of Science, Innovation and Universities and co-funded by the European Social Fund. The authors acknowledge support from the Spanish Ministry of Science and Innovation through the “Centro de Excelencia Severo Ochoa 2019–2023” Program (CEX2018-000806-S) and support from the Generalitat de Catalunya through the CERCA Program. Statistical assistance provided by Ana Espinosa Morano was greatly appreciated
- …