Methods We designed a cross‐sectional, observational follow‐up for 284 COVID‐19 patients involving healthy patients, smokers, diabetics, and diabetic plus smokers recruited from May 1, 2020 to June 25, 2020. The clinical features, severity, duration, and outcome of the disease were analyzed. Results Of 284 COVID‐19 patients, the median age was 48 years (range, 18–80), and 33.80% were female. Common symptoms included fever (85.56%), shortness of breath (49.65%), cough (45.42%), and headache (40.86%). Patients with more than one comorbidity (diabetes and smoking) presented as severe‐critical cases compared to healthy patients, diabetics, and smokers. Smokers presented with a lower rate of death in comparison to diabetic patients and diabetic + smoking, furthermore, smoking was less risky than diabetes. Although the mortality rate was high in patients with smokers compared to healthy patients (4.22%, the hazard ratio [HR], 1.358; 95% confidence interval [CI], 1.542–1.100; p = .014), it was less than in diabetics (7.04%, HR 1.531, 95% CI: 1.668–1.337, p = .000), and diabetic plus smoker (10.00%, HR, 1.659; 95% CI, 1.763–1.510; p = .000). Conclusion Multiple comorbidities are closely related to the severity of COVID‐19 disease progression and the higher mortality rate. Smokers presented as mild cases compared to diabetic and diabetic + smoking patients, who presented as severe to critical cases. Although a higher death rate in smokers was seen compared with healthy patients, this was smaller when compared to diabetic and diabetic + smoking patients.

The dissociation constants and limiting molar conductances of benzoic and 2-, 3-, and 4nitrobenzoic acids have been determined in binary mixtures of water with acetone and tetrahydrofuran at 25 "C, respectively. The experimental data were analyzed by means of the Lee and Wheaton equation. The results are compared with those available in literature and in other water + cosolvent mixtures.

Sterically congested adamantylideneadamantanes (1b-g) (X = Br, Cl, F, OH, OEt, OCOCH(3)), homoallylically substituted with equatorial groups (X), react with bromine in 1,2-dichloroethane to give a stable bromonium ion intermediate or a substitution product depending on the nature of the substituent and on the bromine concentration. The nature of the substituent markedly affects the formation constant of the 1:1 pi-complexes, as well as of the formation constant and reactivity of bromonium ion intermediates. The different reactivity of the ionic intermediates, which depends on the nature of substituents, is attributed to bromonium or bromocarbenium character of the intermediate, with the support of theoretical investigations. Ab initio calculations on 1:1 adamatylideneadamantane-Br(2) complexes (2a-f) show that the substituent affects the stability of these species through electrostatic and dispersion effects. Solvent effects may also contribute to modulate the relative stability of these species.

The parathyroid glands play an overall regulatory role in the systemic calcium (Ca 2+ ) homeostasis. The purpose of the present study was to demonstrate the presence of the Ca 2+ channels transient receptor potential vanilloid (TRPV) 5 and TRPV6 in human parathyroid glands. Semi-quantitative and quantitative PCR was carried out to evaluate the presence of TRPV5 and TRPV6 mRNAs in sporadic parathyroid adenomas and normal parathyroid glands. Western blot and immunocytochemical assays were used to assess protein expression, cellular localization and time expression in primary cultures from human parathyroid adenoma. TRPV5 and TRPV6 transcripts were then identified both in normal and pathological tissues. Predominant immunoreactive bands were detected at 75-80 kD for both vanilloid channels. These channels co-localized with the calcium-sensing receptor (CASR) on the membrane surface, but immunoreactivity was also detected in the cytosol and around the nuclei. Our data showed that western blotting recorded an increase of protein expression of both channels in adenoma samples compared with normal glands suggesting a potential relation with the cell calcium signalling pathway and the pathological processes of these glands.