Consequences of COVid-19 in Latin American dentists in the first year of the pandemic, the period prior to vaccination campaigns.

Objectives: The aim of this investigation was to assess the impact of the COVID-19 pandemic on dentists in Latin America during the initial year of the outbreak, specifically within the timeframe preceding vaccination campaigns. This study determined the various facets in which dentists were affected and exactly what proportion of them was harmed. Methods: A comprehensive 33 question survey was distributed across 19 Latin American countries after the first year of the COVID-19 pandemic's presence in the region. Results: There was an absence of statistically significant differences in responses among the surveyed countries in Latin America, with the exception of four questions out of the total 33. Some relevant findings of Latin American were: one in three dental professionals experienced discrimination based on their occupation. Concurrently, three out of four dentists reported initiating new activities to lessen discomfort. Notably, 8.63 % of respondents sought assistance from a psychologist or psychiatrist, while 17.71 % resorted to the consumption of psychoactive substances within the first year of the pandemic.Furthermore, 7.28 % of the professionals indicated that they still had not obtained all the necessary personal protective equipment for their work and 92.05 % disclosing that they personally financed these essential resources. A certain percentage of dentists stated that the quality of care decreased due to the implementation of the new safety measures (40.03 %) or due to their own feelings during patient interactions (23.11 %). Lastly, 38.85 % of dentists contemplated leaving the profession. Conclusions: The impact of the COVID-19 pandemic on dentists was decidedly adverse, manifesting both in personal and professional fields, despite the diverse measures undertaken by these professionals to mitigate its effects.

Development of an ultra-thin parallel plate ionization chamber for dosimetry in FLASH radiotherapy.

BACKGROUND: Conventional air ionization chambers (ICs) exhibit ion recombination correction factors that deviate substantially from unity when irradiated with dose per pulse magnitudes higher than those used in conventional radiotherapy. This fact makes these devices unsuitable for the dosimetric characterization of beams in ultra-high dose per pulse as used for FLASH radiotherapy. PURPOSE: We present the design, development, and characterization of an ultra-thin parallel plate IC that can be used in ultra-high dose rate (UHDR) deliveries with minimal recombination. METHODS: The charge collection efficiency (CCE) of parallel plate ICs was modeled through a numerical solution of the coupled differential equations governing the transport of charged carriers produced by ionizing radiation. It was used to find out the optimal parameters for the purpose of designing an IC capable of exhibiting a linear response with dose (deviation less than 1%) up to 10 Gy per pulse at 4 µ $\umu$ s pulse duration. As a proof of concept, two vented parallel plate IC prototypes have been built and tested in different ultra-high pulse dose rate electron beams. RESULTS: It has been found that by reducing the distance between electrodes to a value of 0.25 mm it is possible to extend the dose rate operating range of parallel plate ICs to ultra-high dose per pulse range, at standard voltage of clinical grade electrometers, well into several Gy per pulse. The two IC prototypes exhibit behavior as predicted by the numerical simulation. One of the so-called ultra-thin parallel plate ionization chamber (UTIC) prototypes was able to measure up to 10 Gy per pulse, 4 µ $\umu$ s pulse duration, operated at 300 V with no significant deviation from linearity within the uncertainties (ElectronFlash Linac, SIT). The other prototype was tested up to 5.4 Gy per pulse, 2.5 µ $\umu$ s pulse duration, operated at 250 V with CCE higher than 98.6% (Metrological Electron Accelerator Facility, MELAF at Physikalisch-Technische Bundesanstalt, PTB). CONCLUSIONS: This work demonstrates the ability to extend the dose rate operating range of ICs to ultra-high dose per pulse range by reducing the spacing between electrodes. The results show that UTICs are suitable for measurement in UHDR electron beams.

Use of High-Flow Nasal Cannula in Patients With Pneumonia and Hypoxemic Respiratory Failure at Altitudes Above 2600 m: What Is the Best Predictor of Success?

Introduction: The use of high-flow nasal cannulas (HFNC) in patients with hypoxemic ventilatory failure reduces the need for mechanical ventilation and does not increase mortality when intubation is promptly applied. The aim of the study is to describe the behavior of HFNC in patients who live at high altitudes, and the performance of predictors of success/failure of this strategy. Methods: Prospective multicenter cohort study, with patients aged over 18 years recruited for 12 months in 2020 to 21. All had a diagnosis of hypoxemic respiratory failure secondary to pneumonia, were admitted to intensive care units, and were receiving initial management with a high-flow nasal cannula. The variables assessed included need for intubation, mortality in ICU, and the validation of SaO2, respiratory rate (RR) and ROX index (IROX) as predictors of HFNC success / failure. Results: One hundred and six patients were recruited, with a mean age of 59 years and a success rate of 74.5%. Patients with treatment failure were more likely to be obese (BMI 27.2 vs 25.5; OR: 1.03; 95% CI: .95-1.1) and had higher severity scores at admission (APACHE II 12 vs 20; OR 1.15; 95% CI: 1.06-1.24). Respiratory rates after 12 (AUC .81 CI: .70-.92) and 18 h (AUC .85 CI: .72-0.90) of HFNC use were the best predictors of failure, performing better than those that included oxygenation. ICU mortality was higher in the failure group (6% vs 29%; OR 8.8; 95% CI:1.75-44.7). Conclusions: High-flow oxygen cannula therapy in patients with hypoxemic respiratory failure living at altitudes above 2600 m is associated with low rates of therapy failure and a reduced need for mechanical ventilation in the ICU. The geographical conditions and secondary physiological changes influence the performance of the traditionally validated predictors of therapy success. Respiratory rate <30 proved to be the best indicator of early success of the device at 12 h of use.

Hyperglycemia in Acute COVID-19 is Characterized by Adipose Tissue Dysfunction and Insulin Resistance

COVID-19 has proven to be a metabolic disease resulting in adverse outcomes in individuals with diabetes or obesity. Patients infected with SARS-CoV-2 and hyperglycemia suffer from longer hospital stays, higher risk of developing acute respiratory distress syndrome (ARDS), and increased mortality compared to those who do not develop hyperglycemia. Nevertheless, the pathophysiological mechanism(s) of hyperglycemia in COVID-19 remains poorly characterized. Here we show that insulin resistance rather than pancreatic beta cell failure is the prevalent cause of hyperglycemia in COVID-19 patients with ARDS, independent of glucocorticoid treatment. A screen of protein hormones that regulate glucose homeostasis reveals that the insulin sensitizing adipokine adiponectin is reduced in hyperglycemic COVID-19 patients. Hamsters infected with SARS-CoV-2 also have diminished expression of adiponectin. Together these data suggest that adipose tissue dysfunction may be a driver of insulin resistance and adverse outcomes in acute COVID-19.

Saliva, a relevant alternative sample for SARS-CoV2 detection

BackgroundCurrently, COVID-19 diagnosis relies on quantitative reverse-transcriptase polymerase chain reaction (RT-qPCR) from nasopharyngeal swab (NPS) specimens, but NPSs present several limitations. The simplicity, low invasive and possibility of self-collection of saliva imposed this specimen as a relevant alternative for SARS-CoV-2 detection. However, the discrepancy of saliva test results compared to NPSs made of its use controversial. Here, we proposed to assess Salivettes(R), as a standardized saliva collection device, and to compare SARS-CoV-2 positivity on paired NPS and saliva specimens. MethodsA total of 303 individuals randomly selected among those investigated for SARS-CoV-2 were enrolled, including 30 (9.9%) patients previously positively tested using NPS (follow-up group), 90 (29.7%) mildly symptomatic and 183 (60.4%) asymptomatic. ResultsThe RT-qPCR revealed a positive rate of 11.6% (n=35) and 17.2% (n=52) for NPSs and saliva samples, respectively. The sensitivity and specificity of saliva samples were 82.9% and 91.4%, respectively, using NPS as reference. The highest proportion of discordant results concerned the follow-up group (33.3%). Although in the symptomatic and asymptomatic groups the agreement exceeded 90.0%, 17 individuals were detected positive only in saliva samples, with consistent medical arguments. ConclusionSaliva collected with Salivette(R) demonstrated more sensitive for detecting symptomatic and pre-symptomatic infections.

GNP-GAPDH1-22 nanovaccines prevent neonatal listeriosis by blocking microglial apoptosis and bacterial dissemination.

Clinical cases of neonatal listeriosis are associated with brain disease and fetal loss due to complications in early or late pregnancy, which suggests that microglial function is altered. This is believed to be the first study to link microglial apoptosis with neonatal listeriosis and listeriosis-associated brain disease, and to propose a new nanovaccine formulation that reverses all effects of listeriosis and confers Listeria monocytogenes (LM)-specific immunity. We examined clinical cases of neonatal listeriosis in 2013-2015 and defined two useful prognostic immune biomarkers to design listeriosis vaccines: high anti-GAPDH1-22 titres and tumor necrosis factor (TNF)/interleukin (IL)-6 ratios. Therefore, we developed a nanovaccine with gold glyco-nanoparticles conjugated to LM peptide 1-22 of GAPDH (Lmo2459), GNP-GAPDH1-22 nanovaccinesformulated with a pro-inflammatory Toll-like receptor 2/4-targeted adjuvant. Neonates born to non-vaccinated pregnant mice with listeriosis, showed brain and vascular diseases and significant microglial dysfunction by induction of TNF-α-mediated apoptosis. This programmed TNF-mediated suicide explains LM dissemination in brains and livers and blocks production of early pro-inflammatory cytokines such as IL-1ß and interferon-α/ß. In contrast, neonates born to GNP-GAPDH1-22-vaccinated mothers before LM infection, did not develop listeriosis or brain diseases and had functional microglia. In nanovaccinated mothers, immune responses shifted towards Th1/IL-12 pro-inflammatory cytokine profiles and high production of anti-GAPDH1-22 antibodies, suggesting good induction of LM-specific memory.

Crystal structure of 3-benzamido-1-(4-nitro-benz-yl)quinolinium tri-fluoro-methane-sulfonate.

In the title compound, C23H18N3O3 (+)·CF3SO3 (-), the asymmetric unit contains two crystallographically independent organic cations with similar conformations. Each cation shows a moderate distortion between the planes of the amide groups and the quinolinium rings with dihedral angles of 14.90 (2) and 31.66 (2)°. The quinolinium and phenyl rings are slightly twisted with respect to each other at dihedral angles of 6.99 (4) and 8.54 (4)°. The tri-fluoro-methane-sulfonate anions are linked to the organic cations via N-H⋯O hydrogen-bonding inter-actions involving the NH amide groups. In the crystal, the organic cations are linked by weak C-H⋯O(nitro group) inter-actions into supramol-ecular chains propagating along the b-axis direction.

Crystal structure of N,N'-bis-[(pyridin-4-yl)meth-yl]naphthalene di-imide.

In the centrosymmetric title compound, C26H16N4O4 {systematic name: 6,13-bis-[(pyridin-4-yl)meth-yl]-6,13-di-aza-tetra-cyclo-[6.6.2.0(4,16)0(11,15)]hexa-deca-1,3,8,10,15-pantaene-5,7,12,14-tetrone}, the central ring system is essentially planar [maximum deviation = 0.0234 (8) Å] and approximately perpendicular to the terminal pyridine ring [dihedral angle = 84.38 (3)°]. The mol-ecules displays a trans conformation with the (pyridin-4-yl)methyl groups on both sides of the central naphthalene di-imide plane. In the crystal, mol-ecules are linked by π-π stacking between parallel pyridine rings [centroid-centroid distances = 3.7014 (8) and 3.8553 (8) Å] and weak C-H⋯O hydrogen bonds, forming a three-dimensional supra-molecular architecture.

[Prevalence of Barrett's esophagus in non-selected patients submitted to esophagogastroduodenoscopy and associated risk factors]. / Prevalencia de esófago de Barrett en pacientes no seleccionados sometidos a esofagogastroduodenoscopia y factores de riesgo asociados.

OBJECTIVE: To establish the prevalence of the Barrett esophagus (BE) in non-selected patients who underwent upper gastrointestinal endoscopy (UGE) and identified risk factors associated. METHODS: Case-control study on patients who underwent UGE between 2001-2003. Demographic data was gathered as well as the presence of esophagitis, H. pylori, hiatal hernia presence and length, nighttime symptoms, smoking, and alcohol consumption. RESULTS: The global frequency of EB was 0.26%. Average age in patients with EB was 57.3 +/- 17 years old against 49 +/- 15 years old on the control group (p = 0.16). 69% of the patients with EB were men compared to 56% on the control group (p = 0.41). No difference regarding the presence of hiatal hernia was found between EB (79.6%) and patients without EB (72.5%) (p = 0.75). However, patients with EB presented a longer hiatal hernia (p < 0.05). There was no difference regarding the presence of esophagitis (p = 0.32), H. pylori (p = 0.61), smoking (p = 0.39), alcohol consumption (p = 0.34), nocturnal symptoms (p = 0.53) or extra-esophageal manifestations (p = 0.31). A significant difference existed regarding the presence of heartburn and the length of symptoms: patients with EB stated a history longer than 5 years in comparison with the control group (p < 0.005 and < 0.01 respectively). CONCLUSIONS: The frequency of EB was 0.26% in Mexican non-selected population; the extents of hiatal hernia and history heartburn as well as a longer duration of symptoms were significantly associated to EB.

[Evaluation of the symptomatology and quality of life in functional dyspepsia before and after Helicobacter pylori eradication treatment]. / Evaluación de la sintomatología y calidad de vida en la dispepsia funcional antes y después de tratamiento de erradicación de H. pylori.

BACKGROUND: Whether H. pylori infection plays a role in FD is ill defined; however, it is recommended to prescribe eradication treatment in patients with dyspepsia without alarm symptoms. Results of this advice are controversial, principally due to absence of instruments that provide an objective measure of changes in symptoms and quality of life. OBJECTIVE: Our aim was to evaluate significant changes in symptom severity and quality of life in patients with functional dyspepsia (FD) following Helicobacter pylori (H. pylori) eradication treatment. METHODS: We conducted an open clinical trial in adult patients with FD who were H. pylori-positive by means of 14C breath test. Treatment consisted of 2 weeks on lanzoprazole, amoxicillin, and clarithromycin. Score change on the severity of dyspepsia assessment (SODA) test instrument was used to evaluate modifications in symptom severity and quality of life. RESULTS: One hundred patients were included in this trial; treatment compliance was observed in 77% of these, while cure of H. pylori infection was obtained in 82.7% of patients. Only 11.7% displayed absence of dyspepsia symptoms and improvement in quality of life. No significant changes were obtained in global assessment nor in pain, or symptoms in health perception quality of life when initial SODA scores were compared with after-treatment results. CONCLUSIONS: There was no improvement of FD symptoms or quality of life after H. pylori eradication treatment.