Temporal profile of HEV RNA concentration in blood and stool from patients with acute uncomplicated hepatitis E in a region with genotype 1 predominance

Acute hepatitis E virus (HEV) is associated with viremia and faecal excretion of the virus. The information on duration and temporal pattern of viremia and faecal shedding in HEV infection is important, but is not available. Serial serum and stool specimens were collected from patients with acute hepatitis E (typical clinical picture, serum alanine aminotransferase levels > 5‐folds the upper limit of normal and presence of IgM anti‐HEV), beginning from within 7 days of the onset of symptoms. HEV RNA concentrations were measured in sera and 10% stool suspensions, using a real‐time Taqman‐based nucleic acid amplification assay. Seventeen patients (median age 25 [range 19‐61] years; all men) were enrolled within a median of 5 (range 3‐8) days of the onset of the first symptom and provided 113 serum specimens and 71 stool specimens. The median (range) highest levels of serum bilirubin, alanine aminotransferase and aspartate aminotransferase in the patients were 10.3 (5.9‐43.4) mg/dL, 1817 (442‐4642) IU/L and 1016 (88‐4561) IU/L, respectively. All the 17 patients had demonstrable viremia, and 12 of the 13 patients who were tested had faecal excretion at one or more time points. The HEV RNA titres were the highest in the early phase of disease and declined rapidly with time, becoming nondetectable in the serum by day 20 and in the stool by day 21. In most of the patients with acute uncomplicated acute hepatitis E, the degree of viremia and faecal shedding decline quickly after the onset of clinical illness and rapidly disappear in parallel with each other.     

Synthesis, anti-inflammatory activity, and QSAR study of some Schiff bases derived from 5-mercapto-3-(4′-pyridyl)-4H-1,2,4-triazol-4-yl-thiosemicarbazide

The purpose of this research is to synthesize better anti-inflammatory compounds derived from 5-mercapto-3-(4′-pyridyl)-4H-1,2,4-triazol-4-yl-thiosemicarbazide (5). 2-Substituted-N-[3-(pyridin-4-yl)-5-sulfanyl-4H-1,2,4-triazol-4-yl]hydrazine carbothioamide derivatives (6a–j)/(7a–e) are synthesized by the condensation of 5 with variously substituted aromatic aldehydes/1H-indole-2,3-diones, respectively, under conventional and microwave irradiation methods. The microwave method is found to be superior with higher chemical yields, tremendous reduction in time, and is environmentally benign as compared to conventional heating method. The chemical structures of the newly synthesized compounds (6/7) have been confirmed by IR, ¹H NMR, and ¹³C NMR spectra and have been evaluated for anti-inflammatory activity by carrageenan-induced acute paw edema method in rats.     

In Vivo Evaluation of Eclipta alba Extract as Anticancer and Multidrug Resistance Reversal Agent

The present study investigates the anticancer and multidrug resistance (MDR) reversal potential of hydro-alcoholic Eclipta alba extract (EAE) through in vivo experiments. Diethylnitrosamine (DEN) and 2-acetylaminofluorene (AAF) were used for liver cancer induction in animal model, whereas for MDR induction, AAF was used. The level of antioxidant enzymes was studied in serum along with biochemical parameters. Cancer and MDR-induced liver cells have higher levels of reactive oxygen species (ROS) and, in turn, are responsible for the maintenance of the cancer phenotype. Treatment with EAE declines the ROS level and revealed the ROS scavenging properties. Alfa feto protein levels were found to increase significantly in cancer-induced animals confirming induction and progression of liver cancer, EAE treatment was found to bring back the altered levels within normal range indicating the therapeutic effect of plant extract over liver cancer. Zymogram showed the inhibition of MMPs and RT-PCR analysis revealed that the mRNA expression of nuclear factor-kB was markedly decreased upon EAE treatment. Further, our results showed that EAE could significantly inhibit mdr1 gene encode P-glycoprotein expression. Our data suggest that EAE is a novel anticancer and potent MDR reversal agent and may be a potential adjunctive agent for tumor chemotherapy.     

High mortality and residual kidney damage with Coronavirus disease-19-associated acute kidney injury in northern India

Clinical and Experimental Nephrology - Acute kidney injury (AKI) is associated with morbidity and mortality in COVID-19 patients. The incidence of AKI and its outcomes vary in different parts of...     

Oral and oropharyngeal high-risk HPV prevalence,HIV status,and risk behaviours in a cohort of South African men who have sex with men

Data lag is evident when observing studies focussing on human papillomavirus (HPV) prevalence in the head and neck of men who have sex with men (MSM) in Southern Africa. Sexual behaviours other than anal intercourse, and associated factors are similarly underreported. HPV vaccination has not yet commenced for this population group. One hundred and ninety-nine MSM were enrolled in this study. Participants completed a questionnaire followed by a clinical oral examination, and a rinse-and-gargle specimen in Thinprep^® vials containing Preservcyt^® solution was collected. Detection and genotyping for high-risk HPV were done by an automated system (Abbott^® m2000sp). Six percent of MSM in this cohort had high-risk HPV present in the mouth/oropharynx. This cohort averages 29 years of age, more than half were unemployed (53.3%), and 66.8% were human immunodeficiency virus (HIV) seropositive. The most common sexual practice was anal sex (69.4%) followed by oral sex (28.6%), and by rimming (9.6%). A significant association between oral insertive sex and oral/oropharyngeal HPV status was demonstrated (p = 0.0038; phi coefficient = 0.20). An incidental but significant association between rimming and HIV status was found (p = 0.0046; phi coefficient = 0.19), and HIV seropositive participants had higher oral/oropharyngeal HPV presence. The HPV prevalence of 6% reported in this study is in alignment with global reports. The prevalence of oral/oropharyngeal HPV in this MSM cohort was influenced by sexual practices. MSM participants who practiced rimming appear to be at higher risk of HIV acquisition. Given the transmission routes of HPV in this vulnerable population, vaccination must be urgently studied as an intervention for prevention.     

Eosinophilic Mucus Chronic Rhinosinusitis: Clinical Subgroups or a Homogeneous Pathogenic Entity?

BACKGROUND: Eosinophilic mucus chronic rhinosinusitis (EMCRS) can be subclassified using the criteria of detection of fungi in eosinophilic mucus and systemic fungal allergy. Allergic fungal sinusitis (AFS), a subgroup of EMCRS characterized by the presence of fungal allergy, is proposed to be an immunoglobulin (Ig)E-driven disease, distinct from other EMCRS subgroups. However, our recent studies cast doubt on the central pathogenic role of allergy in AFS. The purpose of this study was to examine the clinical features of EMCRS patients from the different subcategories to determine the relevance of this classification system. METHOD: The demographic, clinical, and immunologic characteristics of the EMCRS subgroups were examined prospectively and compared with three control groups: healthy volunteers, allergic rhinitis with fungal allergy, and chronic rhinosinusitis without eosinophilic mucus. RESULTS: EMCRS patients with allergy were younger than those without. There was no significant difference in clinicopathologic parameters between EMCRS subgroups. As a single group, EMCRS had a more severe sinus disease compared with chronic rhinosinusitis patients. CONCLUSIONS: AFS was not clinically distinct from other subgroups of EMCRS. However, eosinophilic mucus may mark a more severe and distinct form of sinus disease.     

Solution structure of zinc-seamed C-alkylpyrogallol[4]arene dimeric nanocapsules

The structural stability and solution geometry of zinc-seamed-C-propylpyrogallol[4]arene dimers has been studied in solution using in situ neutron scattering and 2D-DOSY NMR methods. In comparison with the structures of the analogous copper-/nickel-seamed dimeric entities, the spherical geometry of the PgC₃Zn species (R = 9.4 Å; diffusion coefficient = 1.05 × 10⁻¹⁰ m² s⁻¹) is larger due to the presence of ligands at the periphery in solution. This enhanced radius in solution due to ligation is also consistent with the findings of model molecular dynamics simulations of the zinc-seamed dimers.

Solid-state core geometry of zinc-seamed C-propylpyrogallol[4]arene dimers is retained in solution; however, external ligands exchange with solvent molecules.

A supramolecular assembly can be defined as a complex entity, such as a DNA double helix, held together by non-covalent bonds. Such complex large entities are formed via molecular self-assembly, a process taking far fewer steps than does a conventional synthesis of a single molecule of similar dimensions. The ease of formation, high yield, and possible practical applications as functional materials are some of the factors that have spurred a widespread interest in supra- and supermolecular assemblies.^1–6One group of such assemblies comprises the metal-seamed pyrogallol[4]arene nanocapsules (Fig. 1).^1,7 Although these nanocapsules have now been synthesized with a selection of alkyl groups, metals, guests and axial ligands, only a few have been examined in solution.^8–15 Our motivation in studying solution-phase architectures is to determine whether the solution structures conform to the solid-state geometries. Many nanocapsules, specifically transition metal (Cu/Ni)-seamed hexamers and dimers and hydrogen-bonded dimers, retain their solid-state geometry in solution.^10,13 In contrast, Ga- and Ga/Zn-seamed pyrogallol[4]arene hexamers rearrange from spheres in the solid state to toroids in solution.¹² Similarly, the hydrogen-bonded PgC₁⊂ferrocene/PgC₆⊂pyrene nanotubes rearrange to dimers in solution.^14,15 Solution-phase studies also have allowed us to discover novel structures of species that were either difficult to crystallize or expected to be unstable in solution.^9,11 For example, the ellipsoidal and tubular architectures of the PgC₁₇Cu and PgC₁Fe nanoassemblies, respectively, have been studied exclusively in solution.^9,11Open in a separate windowFig. 1(A) Top view of pyrogallol[4]arene; (B) front view of pyrogallol[4]arene; (C) top view of the C-alkylpyrogallol[4]arene zinc-seamed dimer illustrating the approximate radius of the capsule; (D) front view of the C-alkylpyrogallol[4]arene dimer. For clarity alkyl groups and guest pyridine molecule are removed from the figures. O: red, M (metal): light blue, C: grey, N: blue, H: white.The current study and analysis focus on the solution structure of the original dimeric pyrogallol[4]arene-based nanocapsules: [Zn₈(C-propylpyrogallol[4]arene)₂(pyridine)₇(DMSO)₁⊂pyridine], with propyl R-groups, a pyridine guest and pyridine/DMSO axial ligands (Fig. 1C and D, propyl R-groups and guest pyridine molecule are removed for clarity).¹⁶ The zinc dimer is composed of two pyrogallol[4]arene subunits that are coordinated by the ring of eight Zn⁺² ions across the equatorial belt. The metal atoms displace 16 of the 24 hydroxyl protons of the pyrogallols to seam this spherical framework. Each of the zinc centers is ligated by four phenoxy groups, two from each pyrogallol, along with an axial DMSO or pyridine ligand, that gives a square pyramidal configuration to the metal center. The central phenoxy group from each pyrogallol is bridged between two adjacent zinc centers, whereas the two exterior phenoxy groups are each ligated to a single zinc center and hydrogen-bonded to a phenoxy group on the neighboring pyrogallol subunit, making the overall assembly neutral. In the transition from pentacoordinated Zn in the solid state to tetracoordinated Zn in the gas phase, as a result of the MALDI-TOF analysis, this local Zn–O binding geometry is essentially preserved.^16–18 Of course, thermal fluctuations do occur, although, as we shall show via molecular dynamics simulations, the overall shape remains roughly spherical.The PgC₃Zn dimeric nanocapsule was synthesized by adding 1 equiv. of PgC₃ (0.01 mol L⁻¹), 4 equiv. of zinc(ii) nitrate (0.04 mol L⁻¹), and 14 equiv. of pyridine in DMSO solvent. The solution was heated, sonicated, and left overnight to obtain yellow crystals of the dimer. The unit cell was confirmed and the crystals were filtered and dissolved in d6-DMSO at mass fractions of 1% and 5% for SANS measurements. Preferential deuteration of solvent for SANS studies enhances the coherent scattering and improves the contrast between the solute and the solvent. The samples were left overnight to ensure saturation without precipitation, and the SANS measurement was conducted at 25 °C on the NG3 30m SANS instrument at the NIST Center for Neutron Research in Gaithersburg, MD.¹⁹ The collected scattering data was reduced and analyzed using IgorPro²⁰ incorporating the instrumental q-resolution function.The measurements on the dimeric sample at mass fractions of both 1% and 5% were conducted to ensure sufficient scattering and to detect a concentration dependence of the capsular structure. The scattering length densities (SLDs) of the solute and solvent were calculated and held fixed for data analyses. The SLDs of the solvent (d6-DMSO) and solute (PgC₃Zn dimer) were fixed at 5.28 × 10⁻⁶ Å⁻² and 1.37 × 10⁻⁶ Å⁻², respectively.The reduced SANS data was fitted globally, with the two data sets corresponding to different mass fractions being modelled simultaneously to obtain the best fit. The data was fitted to various cylindrical, ellipsoidal and core–shell models to detect the occurrence of structural transformation. It was quickly found, however, that the entity does not have a core–shell, ellipsoidal or cylindrical geometry (ESI^†). Previous studies on copper and nickel nanocapsules have indicated the presence of both dimers and hexamers in solution;¹³ hence, it was important to investigate the possible presence of multiple species with similar or different architectures. For this purpose, the data was globally fitted to the bimodal Schulz sphere and Schulz sphere models (ESI^†). The calculated SLDs for the hexamer (1.56 × 10⁻⁶ Å⁻²), dimer (1.37 × 10⁻⁶ Å⁻²) and solvent (5.28 × 10⁻⁶ Å⁻²) were held fixed for global fitting. An unphysical volume fraction was obtained for the second spherical species in the bimodal Schulz sphere global fit, clearly indicating that the PgC₃Zn sample has a unimodal distribution. In fact, the data for the PgC₃Zn was fit best to a polydisperse sphere (Schulz sphere) model^21,22 with a chi-sqrt value of 1.156 and a radius of ≈9.4 Å, a result indicating the presence of only one spherical assembly in solution (ESI;^†Fig. 1 and ​and22).Open in a separate windowFig. 2SANS intensity from the zinc-seamed C-propylpyrogallol[4]arene dimer at mass fractions of 1% and 5%. The solid line is the model fit with a polydisperse sphere model. The error bars on the SANS data points represent one standard deviation in the measured intensity. The upturn seen at q < 0.02 A⁻¹ is likely due to the presence of a small fraction of aggregates of nanocapsules in solution. Analysis is restricted to larger q-values to focus on the scattering from individual nanocapsules.In comparison with the radii of the PgC₃Cu and PgC₃Ni dimers, the radius obtained for the PgC₃Zn dimer is ≈2.4 Å larger, and the size/diameter of the PgC₃Zn dimer (≈18.8 Å) is intermediate between that of a PgC₃Cu/Ni dimer (≈14 Å) and that of a PgC₃Cu/Ni hexamer (≈20 Å). This comparison indicates that PgC₃Cu and PgC₃Ni most likely lose their ligands in solution. As this was the case, we examined the dimensions of the solid-state PgC₃Zn dimer (XRD). The solid-state radius of the PgC₃Zn dimer is ≈9.4 Å and ≈7 Å with and without external pyridine/DMSO ligands, respectively.¹⁶ The geometric dimensions obtained for the PgC₃Zn dimer in the solution phase are nearly identical to those obtained in the solid state. Thus, SANS data analysis for the solvent-solubilized PgC₃Zn dimer not only confirms its spherical shape and structural stability in solution but also reveals the preference for a square pyramidal metal bonding geometry, which differs from the distorted square planar geometry found in other metal-seamed (PgC₃Cu, PgC₃Ni) dimers in solution.These radii obtained for the PgC₃Zn dimer are also commensurate with those calculated from molecular dynamics simulations of PgC₀Zn dimers with and without 8 ligated molecules. These mixed quantum-classical calculations were performed using the AMBER program suite,²³ with a tight-binding DFT scheme (DFTB3)²⁴ being used to model the Zn, O, and bridging H atoms as well as the atoms of the ligand. All other atoms of the dimer were treated classically using the gaff2 force field.²⁵ The simulation results reported here reflect the dynamics of room-temperature gas-phase species. In the absence of the ligands, the average dimer radius was found to be 4.9 ± 0.1 Å, whereas with 8 ligated ammonia molecules the average radius was 7.1 ± 0.1 Å, with 8 ligated pyridine molecules the average radius was found to be 9.8 ± 0.1 Å, and with 8 ligated DMSO molecules the average radius was found to be 8.4 ± 0.7 Å (the uncertainties here are standard deviations of the average radii as measured from the instantaneous center of mass of the 8 Zn atoms. That is, they reflect the time-dependent thermal fluctuations of the dimer capsule rather than uncertainties in the calculated forces and simulation methodology). The larger uncertainty associated with the calculated average radius for the DMSO-ligated species here derives from the nonlinear bonding at the oxygen and nonplanar bonding at the sulfur in DMSO and the rotation about the oxygen–sulfur bond. In the above ligated species, the calculated radius of the roughly spherical dimer cage itself also differs from that of the non-ligated dimer, being larger by about 0.1 Å in each case.The solution-phase behavior of PgC₄Zn was further investigated using diffusion-ordered NMR spectroscopy (DOSY). Specifically, we investigated the encapsulation of pyridine within zinc dimers.Note that we are reporting here the first DOSY NMR study of the metal-seamed pyrogallol[4]arene dimeric framework. The diffusion NMR studies reported by Cohen and co-workers were on hydrogen-bonded pyrogallol[4]arene, octahydroxypyridine[4]arene^26,27 and resorcin[4]arene nanocapsules in CDCl₃.²⁸ Atwood et al. have more recently reported DOSY NMR studies on PgC₄Ga hexamers, PgC₄GaZn toroids and hydrogen-bonded PgC₆⊂pyrene nanoassemblies in d6-acetone.²⁹Capsules of PgC₄Zn⊂pyridine for the NMR studies were synthesized by mixing methanolic solutions of C-butylpyrogallol[4]arene, zinc nitrate and pyridine in the ratio of 1 : 4 : 14. Sonication yielded a precipitate of zinc dimers. A 2% solution of PgC₄Zn⊂pyridine was prepared in d6-DMSO for the NMR measurements. Notably, we used a different tail (butyl) here, versus the previously studied C-propyl tail, as the tail length has been shown to not impact the self-assembled metal-coordinated core architecture of the nanocapsule.The diffusion coefficients of the phenoxy hydroxyls, alkyl moieties and bound pyridine are similar (Fig. 3), indicating the structural integrity of the PgC₄Zn dimer in DMSO solvent. Overall, the macrocycle/capsule and bound guest pyridine have a diffusion coefficient of 1.04 × 10⁻¹⁰ m² s⁻¹. The integration of bound versus free pyridine is 1 : 8 suggesting that the external pyridine ligand has exchanged with DMSO. The diffusion coefficients of the “free” pyridine ligand, solvent DMSO, methanol and water are 6.79 × 10⁻¹⁰, 7.00 × 10⁻¹⁰, 8.71 × 10⁻¹⁰ and 9.08 × 10⁻¹⁰ m² s⁻¹, respectively. The diffusion coefficient of the bound pyridine is about 6.5 times lower than that of a free pyridine.Open in a separate windowFig. 3The DOSY NMR spectra of the [PgC₄Zn⊂(pyridine)] dimer. The Y-axis on the DOSY plot is displayed as log D.Overall, the combined neutron scattering, diffusion-ordered NMR spectroscopy and molecular dynamics results indicate (a) the structural stability of the dimer in solution; (b) guest encapsulation; (c) fast external ligand exchange with solvent, which can only be captured through SANS; and (d) an increase in the effective radius of the zinc dimer due to ligation at zinc centers showing a preference for square pyramidal bonding.The robustness of dimers demonstrated in this study justifies the use of these frameworks for guest encapsulation. Furthermore, the presence of exterior ligands affords valuable insight into the nature of guest-ligand communication. Future studies thus will focus on studying these robust frameworks and on variations in their structural properties in response to varying the encapsulated guest.