“Helicobacter pylori treatment guideline: An Indian perspective”: Letter to the editor

Treatment guidelines in many countries for Helicobacter pylori (H. pylori) may differ. Owing to the various characteristics of bacteria, clinical manifestations, resistance to antibiotics and recurrence rate, treatment regimens may change. In this letter, we would like to give an Indian perspective on H. pylori treatment guidelines.     

Objective assessment of the human visual attentional state

Primary objective

The purpose of this study was to develop an objective way to assess human visual attention using the alpha-band component of the visual-evoked potential (VEP).

Design and methods

Six different attentional conditions were tested: eyes-open, eyes-closed, eyes-closed with backwards number counting, and three rapid-serial visual presentation (RSVP) tasks. Eighteen visually normal, young-adult subjects (ages 21–28 years) were tested binocularly at 1 m for each condition on two separate days. The Diopsys? NOVA-TR system was used to obtain the visual-evoked potential (VEP) and extracted alpha wave and its related power spectrum. Additionally, the Visual Search and Attention Test (VSAT) was administered as a subjective measure of visual attention.

Results

Subjects exhibited significant decreases in power in the alpha band when comparing the eyes-closed with the eyes-open conditions, with power in the eyes-closed condition being, on average, twice as large. The response from the other four conditions did not reflect the differential attentional demands. The ratio of the power in the eyes-closed condition to the eyes-open condition in the lower-alpha frequencies (8–10 Hz) was found to be significantly correlated with the group’s performance on the VSAT, especially the 10-Hz component.

Conclusions

An individual’s ability to attenuate their alpha component during visual processing may be a predictor of their visual attentional state. These findings solidify the role of the VEP alpha subcomponent as an objective electrophysiological correlate of visual attention, which may be useful in the diagnosis and treatment of human visual attention disorders in the future.     

Comparison of changes in endothelial cell count and central corneal thickness after phacoemulsification and small-incision cataract surgery: A prospective observational study at a tertiary care center of eastern Uttar Pradesh

Purpose:Morphological stability and functional integrity of corneal endothelium are necessary to maintain long-term corneal transparency. When the number of endothelial cells drops below 450–800 cells/mm², corneal edema, irreversible loss of corneal transparency, and decreased vision occur. There is concern regarding manual small-incision cataract surgery (MSICS) being more harmful to the endothelium in comparison to phacoemulsification. Our study aims to determine which technique maintains the corneal parameters closest to the normal physiological state.Methods:A prospective observational study was conducted over a period of 15 months on 100 eyes, out of which 43 patients underwent phacoemulsification surgery and 57 underwent MSICS. TOPCON SP-1P, Version 1.41, 50–60 Hz frequency, noncontact specular microscope with pachymeter was used to measure endothelial cell count (ECC) and central corneal thickness (CCT) on four occasions: 1 day prior to surgery and on day 1, 3^rd week, and 6^th week after surgery.Results:In total, 100 eyes of 100 subjects were studied with no dropout during the study period. The age range was 40–70 years. There was no statistically significant difference between the preoperative mean ECC and mean CCT in phacoemulsification and SICS groups. A statistically significant difference was observed in the postoperative mean ECC (P < 0.01) and mean CCT (P < 0.001) on day 1 and 3^rd week between the phacoemulsification and SICS groups, respectively. The mean endothelial cell loss at 6 weeks was less with SICS but comparable with phacoemulsification.Conclusion:SICS is significantly faster, less expensive, less technology dependent, can deal with all types of cataracts, is relatively safe, and is more appropriate for advanced cataracts.     

On the specific heat capacity of HITEC-salt nanocomposites for concentrated solar power applications

High specific heat capacity or C_P of molten salt is crucial for concentrated solar power plants as it will enhance the energy density of thermal energy storage. It can be achieved by doping nanoparticles into molten salts. However, reported results show inconsistency in C_P enhancement (positive and negative). Since the results are based on Differential Scanning Calorimeter (DSC) measurements of small batches (<10 mg), the average C_P obtained from these results may not represent the bulk-C_P of the nanocomposite, which is an important parameter from an application viewpoint. Moreover, the methods of salt-nanoparticle composite production lack industrial scalability. In this work, we examined a potentially scalable method based on mechanical shear mixing. The molten-salt of choice was HITEC due to its lower melting point, while inexpensive alumina and silica nanoparticles were used as dopants. To compare and contrast variability in C_P enhancement, the sample selection was made by random sampling; DSC measurement was performed on small-sized batches (<10 mg), and the T-history method was applied on large-sized batches (20 g). While DSC tests indicated a mean decrease in C_P for alumina (−43%) and an increase in C_P for silica nanocomposite (+15%), T-history tests indicated a mean decrement in the bulk-C_P for both alumina (−49%) and silica nanocomposites (−3%). This anomalous behavior in C_P values was further compared using a nonparametric statistical test, the Mann–Whitney U test, which revealed that the C_P of small-sized batches is statistically different from that of large-sized batches. Given their industrial scale of usage, the C_P of the nanocomposite must be measured using both DSC and T-history methods to ascertain the effect of nanoparticles.

The current study highlights the importance of testing the bulk-C_P and statistical inference for examining the specific heat capacity of nanoparticle-infused salt composites using DSC and T-history tests.     

Optical transitions and radiative properties of green emitting Ho3+:YVO4 phosphor

The Ho³⁺-doped YVO₄ phosphors were successfully prepared via a sol–gel process in which citric acid was used as a chelating agent. X-ray diffraction (XRD) confirmed the effective inclusion of Ho³⁺ ions into the host matrix with the formation of single phase YVO₄. The surface morphology was observed using SEM, the results of which showed a grain growth propensity and the agglomeration of prepared phosphors. The V–O (VO₄³⁻) vibration mode was analyzed through Fourier transform infrared (FTIR) spectra. The spectroscopic properties were reported through UV-vis-NIR diffuse reflectance and photoluminescence (PL) spectra. The Judd–Ofelt (J–O) intensity parameters Ω₂ = 0.03 × 10⁻²⁰ cm², Ω₄ = 0.22 × 10⁻²⁰ cm², and Ω₆ = 0.23 × 10⁻²⁰ cm² obtained for the Y_0.97VO₄:0.03Ho³⁺ phosphors were used to obtain the total transition probabilities (A_T), radiative lifetimes (τ_rad) and branching ratios (β) for the certain transitions of Ho³⁺ ions. Under 310 nm UV excitation, the visible emission spectra were measured, and an intense emission was observed around 541 nm (green region) for all the samples. The emission cross-section σ_P(λ) was 3.22 × 10⁻²¹ cm² and the branching ratio (β) was 0.816; these were investigated to capture the optimal concentration of the Y_0.97VO₄:0.03Ho³⁺ phosphor. The estimated color coordinates were observed in the green region of CIE diagram. Ultimately, the superior properties (σ_P(λ), β, and color purity) of Y_0.97VO₄:0.03Ho³⁺ phosphor may make it suitable for green emitting devices.

Ho³⁺-doped YVO₄ phosphors were successfully prepared via a sol–gel process in which citric acid was used as a chelating agent.     

Outcome of Tracheostomy in COVID-19 Patients

IntroductionSince the start of the COVID-19 pandemic 2019, quite a few patients became critical and needed ICU admission with ventilator assistance. Tracheostomy, which was initially performed late during the course of patient on ventilator, has now been considered a procedure that can be performed relatively early as this leads to early weaning of patients and overcomes the shortage of critical beds.ObjectiveThis study aims to focus on the outcomes of tracheotomised COVID-19 patients in terms of survival and any tracheostomy related morbidity.MethodsA prospective study was performed on COVID-19 patients undergoing tracheostomy at this tertiary care teaching hospital, which also was a dedicated centre for treating COVID-19 patients. The duration of this study was from April 2020 to September 2021. Following tracheostomy, all patients were followed up regularly and clinical changes were recorded. Points that were specifically noted were timing of the tracheostomy, change in ventilator settings, tracheostomy related complications, requirement of oxygen, days needed to wean the patient, decanulation, and, if death, the cause of death.ResultsA total of 136 surgical open tracheostomies were performed on COVID-19 patients over the study period. The mean duration of intubation (timing of tracheostomy) was 12 days. A total of 73 out of 136 (53.6%) patients survived. 51 patients (37.5%) got decannulated during the course of the hospital stay. 9 patients were decanulated during the follow up visits and 13 patients were lost to follow up. 63 out of 136 (46.3%) patients died due to COVID pneumonia. Most of the patients who died had gone into multi-organ failure. Air leak syndromes (pneumothorax and pneumomediastinum) were common findings. 10 patients already had surgical emphysema before taking up for tracheostomy and 6 developed 2–3 days after tracheostomy. The most common complication was bleeding, which was seen in 28 out of 136 patients. The Median weaning of period of patients who survived was 5 days.ConclusionPerforming tracheostomy early in COVID-19 patients helps in early weaning of the patient from the ventilator and makes nursing care easier and increases the availability of ICU beds. The mortality rate was 46% amongst the 136 tracheostomies done in COVID-19 patients. Local site bleeding was the most common complication and surgical emphysema was also seen more than routine tracheostomies.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12070-022-03248-1.     

Modulation of biliverdin dynamics and spectral properties by Sandercyanin

Biliverdin IX-alpha (BV), a tetrapyrrole, is found ubiquitously in most living organisms. It functions as a metabolite, pigment, and signaling compound. While BV is known to bind to diverse protein families such as heme-metabolizing enzymes and phytochromes, not many BV-bound lipocalins (ubiquitous, small lipid-binding proteins) have been studied. The molecular basis of binding and conformational selectivity of BV in lipocalins remains unexplained. Sandercyanin (SFP)–BV complex is a blue lipocalin protein present in the mucus of the Canadian walleye (Stizostedion vitreum). In this study, we present the structures and binding modes of BV to SFP. Using a combination of designed site-directed mutations, X-ray crystallography, UV/VIS, and resonance Raman spectroscopy, we have identified multiple conformations of BV that are stabilized in the binding pocket of SFP. In complex with the protein, these conformers generate varied spectroscopic signatures both in their absorption and fluorescence spectra. We show that despite no covalent anchor, structural heterogeneity of the chromophore is primarily driven by the D-ring pyrrole of BV. Our work shows how conformational promiscuity of BV is correlated to the rearrangement of amino acids in the protein matrix leading to modulation of spectral properties.

Biliverdin IX-alpha undergoes rotation around the D-ring pyrrole and displays a broad far-red absorbance on binding to monomeric Sandercyanin variant (orange) compared to the wild-type tetrameric protein (cyan).     

Analysis of COVID-19-associated rhino-orbital-cerebral mucormycosis patients in a tertiary care center in Northern India

Purpose:An unprecedented surge has been noted in rhino-orbital-Cerebral mucormycosis (ROCM) in times of current COVID-19 pandemic. The present prospective study aims to evaluate clinico-epidemiological profile, risk factors, management, and outcome of the cases of ROCM that presented to our tertiary care center during the study period from April to June 2021.Methods:All patients were subjected to complete history taking, ophthalmological examination, and imaging studies. The patients were staged and were treated with intravenous liposomal amphotericin B (AMB) and sino-nasal debridement of local necrotic tissue. Transcutaneous retrobulbar AMB (TRAMB), orbital decompression, and exenteration were instituted as indicated. All patients were followed up for a minimum of 6 months before arriving at the final outcome. Statistical analysis was performed.Results:A total of 49 patients presented during the study period, with a mean age of 42.2 years. The major risk factors included uncontrolled diabetes (89.8%), COVID-19 positivity (51.02%), and concurrent steroid use (38.77%). The most common presenting symptom was facial pain/swelling (43.65%), while the most common presenting sign was deterioration in vision (75.51%). Intravenous liposomal AMB was given to all patients along with sino-nasal debridement (85.71%), TRAMB (57.14%), orbital decompression (14.28%), and exenteration (12.24%). Overall, mortality at 6 months was 22.45% (11 patients). Age more than 60 years, intracranial extension, and HbA1c of more than 8.0% were observed to be statistically significant indicators of mortality.Conclusion:Early suspicion and timely diagnosis of mucormycosis at rhino-orbital stage is warranted in order to salvage life as well as visual function. TRAMB may prove as potentially favorable treatment modality in cases with limited orbital involvement.     

Associations of Emergency Department Visits for Asthma with Precipitation and Temperature on Thunderstorm Days: A Time-Series Analysis of Data from Louisiana,USA, 2010–2012

Background: Studies of thunderstorm asthma to understand risk factors using high-resolution climate data and asthma outcomes on a large scale are scarce. Moreover, thunderstorm asthma is not well studied in the United States.Objectives: We examined whether climate parameters involved in thunderstorms are associated with emergency department (ED) visits for acute asthma attacks in the United States.Methods: We analyzed 63,789 asthma-related, daily ED visits for all age groups, and thunderstorm-associated climate data in Louisiana during 2010 through 2012. We performed time-series analyses using quasi-Poisson regression models with natural cubic splines of date, parish, holiday, day of week, season, daily maximum concentrations of ozone (O3) and fine particulate matter [PM ≤2.5μm in aerodynamic diameter (PM2.5)], and daily mean pressure, precipitation, and temperature. Because of a significant interaction effect between temperature and lightning days on asthma-related visits, we performed stratified analyses by days with/without lightning or thunderstorm (defined by any lightning and precipitation).Results: On thunderstorm days, higher asthma-related ED visits were associated with higher daily mean precipitation [relative risk (RR)=1.145 per 1g/m2/s (95% CI: 1.009, 1.300)] and lower daily mean temperature [RR=1.011 per 1°C change (1.000–1.021)] without carry-over effect to the next non-thunderstorm day. These higher risks were found mainly among children and adults <65 years of age. We observed similar results on lightning days. However, we did not find similar associations for non-thunderstorm or non-lightning days. Daily maximum O3 and PM2.5 levels were not significantly associated with asthma ED visits on thunderstorm days.Discussion: Higher precipitation and lower temperature on thunderstorm days appear to contribute to asthma attacks among people with asthma, suggesting they should consider taking precautions during thunderstorms. EDs should consider preparing for a potential increase of asthma-related visits and ensuring sufficient stock of emergency medication and supplies for forecasted severe thunderstorm days. https://doi.org/10.1289/{"type":"entrez-protein","attrs":{"text":"EHP10440","term_id":"372009825","term_text":"EHP10440"}}EHP10440