Helicobacter pylori infection causes gastric cancer, the third leading cause of cancer death worldwide. More than half of the world's population is infected, making universal eradication impractical. ...Clinical trials suggest that antibiotic treatment only reduces gastric cancer risk in patients with non-atrophic gastritis (NAG), and is ineffective once preneoplastic lesions of multifocal atrophic gastritis (MAG) and intestinal metaplasia (IM) have occurred. Therefore, additional strategies for risk stratification and chemoprevention of gastric cancer are needed. We have implicated polyamines, generated by the rate-limiting enzyme ornithine decarboxylase (ODC), in gastric carcinogenesis. During H. pylori infection, the enzyme spermine oxidase (SMOX) is induced, which generates hydrogen peroxide from the catabolism of the polyamine spermine. Herein, we assessed the role of SMOX in the increased gastric cancer risk in Colombia associated with the Andean mountain region when compared with the low-risk region on the Pacific coast. When cocultured with gastric epithelial cells, clinical strains of H. pylori from the high-risk region induced more SMOX expression and oxidative DNA damage, and less apoptosis than low-risk strains. These findings were not attributable to differences in the cytotoxin-associated gene A oncoprotein. Gastric tissues from subjects from the high-risk region exhibited greater levels of SMOX and oxidative DNA damage by immunohistochemistry and flow cytometry, and this occurred in NAG, MAG and IM. In Mongolian gerbils, a prototype colonizing strain from the high-risk region induced more SMOX, DNA damage, dysplasia and adenocarcinoma than a colonizing strain from the low-risk region. Treatment of gerbils with either α-difluoromethylornithine, an inhibitor of ODC, or MDL 72527 (N(1),N(4)-Di(buta-2,3-dien-1-yl)butane-1,4-diamine dihydrochloride), an inhibitor of SMOX, reduced gastric dysplasia and carcinoma, as well as apoptosis-resistant cells with DNA damage. These data indicate that aberrant activation of polyamine-driven oxidative stress is a marker of gastric cancer risk and a target for chemoprevention.
In this work, compact and porous SiO
2
nanoparticles (NPs) were synthesized using the Stöber and the modified Stöber methods. Water-based nanofluids were characterized by dynamic light scattering, ...scanning electron microscopy, transmission electron microscopy, energy-dispersive spectroscopy, Fourier transform infrared spectroscopy, and X-ray diffraction, and the porosity of the compact and porous SiO
2
samples was measured by N
2
adsorption–desorption isotherms. Thermal wave resonator cavity and inverse photopyroelectric configuration novel techniques were used for the first time to obtain the porous nanoparticles thermal diffusivity (
D
) and effusivity (
e
), respectively. Thermal conductivity (
k
) was obtained from the relationship between them
k
=
e
D
. An increase in the thermal conductivity of the porous SiO
2
NPs was obtained compared to the thermal conductivity of the compact NPs fluids with an enrichment of 14.7 %. Our results are supported by a theoretical model with a thermodynamic approach adapted for the thermal conductivity of porous SiO
2
governed by the parameters of the porosity and nanoparticle size.
Aims: Plant growth‐promoting (PGP) activity of two Azospirillum strains and their effects on foliar and vascular bacterial diseases were evaluated on fresh market and cherry tomato.
Methods and ...Results: Tomato seeds were inoculated with A. brasilense Sp7 or Azospirillum sp. BNM‐65. Four‐week‐old plants were challenge‐inoculated with Clavibacter michiganensis subsp. michiganensis (bacterial canker) or with Xanthomonas campestris pv. vesicatoria (bacterial spot). Azospirillum‐induced PGP was greater on cherry than on fresh‐market tomato. Cherry tomato was more resistant to bacterial canker but more susceptible to bacterial spot than the fresh‐market tomato. Canker severity was not affected by Azospirillum seed treatments. However, leaf‐ and plant‐death were delayed on Azospirillum‐treated plants compared with nontreated controls. Azospirillum increased the bacterial spot severity on cherry but not on fresh‐market tomato.
Conclusions: PGP was observed on both tomato genotypes, although growth effects were larger on cherry tomato. Also, Azospirillum treatments may alter tomato susceptibility to bacterial diseases.
Significance and Impact of the Study: The interaction between PGP rhizobacteria like Azospirillum spp., not known to induce systemic resistance, with plant pathogens distantly located is frequently overlooked. This work demonstrates the importance of this kind of evaluation.
The objective of our study was to describe knowledge, attitudes and practices of Latin-American rheumatology patients regarding management and follow-up of their disease during COVID-19 pandemic. A ...cross-sectional observational study was conducted using a digital anonymous survey. Rheumatic patients ≥ 18 years from non-English-speaking PANLAR countries were included. Our survey included 3502 rheumatic patients living in more than 19 Latin-American countries. Median age of patients was 45.8(36–55) years and the majority (88.9%) was female. Most frequently self-reported disease was rheumatoid arthritis (48.4%). At least one anti-rheumatic treatment was suspended by 23.4% of patients. Fear of contracting SARS-Cov2 (27.7%) and economic issues (25%) were the most common reasons for drug discontinuation. Self-rated disease activity increased from 30 (7–50) to 45 (10–70) points during the pandemic. Communication with their rheumatologist during the pandemic was required by 55.6% of patients, mainly by telephone calls (50.2%) and social network messages (47.8%). An adequate knowledge about COVID-19 was observed in 43% of patients. Patients with rheumatic diseases in Latin America were negatively affected by the COVID-19 pandemic. An increase in self-rated disease activity, a reduction in medication adherence, and hurdles for medical follow-up were reported. Teleconsultation was perceived as a valid alternative to in-person visits during the pandemic.
Objective
The current investigation aimed at studying the sociodemographic, clinical, and neuropsychological variables related to functional outcome in a sample of euthymic patients with bipolar ...disorder(BD) presenting moderate‐severe levels of functional impairment.
Methods
Two‐hundred and thirty‐nine participants with BD disorders and with Functioning Assessment Short Test(FAST) scores equal or above 18 were administered a clinical and diagnostic interview, and the administration of mood measure scales and a comprehensive neuropsychological battery. Analyses involved preliminary Pearson bivariate correlations to identify sociodemographic and clinical variables associated with the FAST total score. Regarding neuropsychological variables, a principal component analysis (PCA) was performed to group the variables in orthogonal factors. Finally, a hierarchical multiple regression was run.
Results
The best fitting model for the variables associated with functioning was a linear combination of gender, age, estimated IQ, Hamilton Depression Rating Scale (HAM‐D), number of previous manic episodes, Factor 1 and Factor 2 extracted from the PCA. The model, including all these previous variables, explained up to 29.4% of the observed variance.
Conclusions
Male gender, older age, lower premorbid IQ, subdepressive symptoms, higher number of manic episodes, and lower performance in verbal memory, working memory, verbal fluency, and processing speed were associated with lower functioning in patients with BD.
Objective
Cognitive reserve (CR) is a concept that was postulated as a protective factor for some clinical symptoms after the observation that there is not a direct relationship between the degree of ...brain damage and its clinical manifestation. This study aimed to explore the association between CR and the main outcomes in bipolar disorder (BD): cognitive functions, psychosocial functioning and perceived quality of life.
Method
A sample of 224 euthymic bipolar patients was assessed with a neuropsychological battery, the Functioning Assessment Short Test and the Medical Outcomes Study 36‐Item Short‐Form Health Survey (SF‐36). CR was calculated through three proxies: estimated premorbid Intelligent Quotient, educational level and occupational attainment. Relationships between CR and cognitive functions, psychosocial functioning and quality of life were assessed by multiple linear regression models.
Results
Higher CR was associated with better cognitive functioning (P < 0.001 in processing speed, working memory, verbal and visual memory, and executive function; P = 0.026 in attention) and better psychosocial functioning (P = 0.008). For quality of life, CR was positively associated with the physical component of the SF‐36 (P = 0.016) but negatively associated with the mental component (P = 0.004).
Conclusion
The results suggest that CR may play an important role in the course and prognosis of bipolar patients and it should be considered in both clinical and research settings related to BD.
Background& Aims Proton pump inhibitors and nonsteroidal anti-inflammatory drugs might prevent esophageal adenocarcinoma in patients with Barrett's esophagus (BE), but there are limited data from ...clinical trials to support this concept. We conducted a randomized, double-blind, placebo-controlled, phase 2 trial to assess the effects of the combination of aspirin (3 different doses) and esomeprazole on tissue concentrations of prostaglandin (PG) E2 in patients with BE with no dysplasia or low-grade dysplasia. Methods Participants were recruited through the multicenter Cancer Prevention Network and randomly assigned to groups that were given 40 mg esomeprazole twice daily in combination with an aspirin placebo once daily (arm A; n = 30), with 81 mg aspirin once daily (arm B; n = 47), or with 325 mg aspirin once daily (arm C; n = 45) for 28 days. We collected esophageal biopsy specimens before and after the intervention period to determine the absolute change in mean concentration of PGE2 (the primary end point). Results Based on data from 114 patients, baseline characteristics were similar among groups. The absolute mean tissue concentration of PGE2 was reduced by 67.6 ± 229.68 pg/mL in arm A, 123.9 ± 284.0 pg/mL in arm B ( P = .10 vs arm A), and 174.9 ± 263.62 pg/mL in arm C ( P = .02 vs arm A). Conclusions In combination with esomeprazole, short-term administration of higher doses of aspirin, but not lower doses or no aspirin, significantly reduced tissue concentrations of PGE2 in patients with BE with either no dysplasia or low-grade dysplasia. These data support further evaluation of higher doses of aspirin and esomeprazole to prevent esophageal adenocarcinoma in these patients. Clinical trial registration number NCT00474903.
•Thermal characterization of centrifuged aromatic citrus oils was studied.•Thermal lens (TL) and open photoacoustic cell (OPC) were used for characterization.•Thermal diffusivity, thermal effusivity ...and thermal conductivity were obtained.•Thermal effusivity and conductivity of green mandarin oil is first time reported.•Absorption coefficients and chemical structure of the citrus oils were determined.
In this work, thermal characterization of centrifuged aromatic citrus oils was studied using thermal lens (TL) and open photoacoustic cell (OPC). The thermal diffusivity (D) was obtained by TL, fitting the critical time parameter of the experimental curves to the theoretical values. An experimental arrangement of non-matched mode lasers with a probe and an excitation lasers was used. On the other hand, the thermal effusivity (e) of the samples was obtained by using OPC. The thermal conductivity (k) was calculated from the relationship between D and e. The thermal parameters obtained were compared with theoretical values in the literature. UV–vis spectroscopy, Attenuated Total Reflectance-Fourier Transform Infrared spectroscopy (ATR-FTIR) and 1H Nuclear Magnetic Resonance (NMR) were used to determine the absorption coefficients and chemical structure of the citrus oils. The importance of this research work was the determination of the thermal parameters of essential oils as an alternative technique for quality control application.
A multicentre survey was designed to evaluate the impact of COVID-19 outbreak on dental practice worldwide, estimate the COVID-19 related symptoms/signs, work attitudes and behaviour and the routine ...use of protective measures and Personal Protective Equipment (PPE).
A global survey using a standardized questionnaire with research groups from 36 countries was designed. The questionnaire was developed and pretested during April 2020 and contained three domains: 1) Personal data; 2) COVID-19 positive rate and symptoms/signs presumably related to the coronavirus; 3) Working conditions and PPE adopted after the outbreak. Countries’ data were grouped by the Country Positive Rate (CPR) during the survey period and by Gross-National-Income per capita. An ordinal multinomial logistic regression model was carried out with COVID-19 self-reported rate referred by dental professionals as dependent variable to assess the association with questionnaire items.
A total of 52,491 questionnaires were returned with a male/female ratio of 0.63. Out of the total respondents, 7,859 dental professionals (15%) reported symptoms/signs compatible with COVID-19. More than half of the sample (n = 27,818; 53%) stated to use FFP2/N95 masks, while 21,558 (41.07%) used eye protection. In the bivariate analysis, CPR and N95/FFP2 were significantly associated (OR = 1.80 95%CI = 1.60/2.82 and OR = 5.20 95%CI = 1.44/18.80, respectively), while Gross-National-Income was not statistically associated with CPR (OR = 1.09 95%CI = 0.97/1.60). The same significant associations were observed in the multivariate analysis.
Oral health service provision has not been significantly affected by COVID-19, although access to routine dental care was reduced due to country-specific temporary lockdown periods. While the dental profession has been identified at high-risk, the reported rates of COVID-19 for dental professionals were not significantly different to those reported for the general population in each country. These findings may help to better plan oral health care for future pandemic events.
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