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The article explores the interrelation between endodontic treatment and systemic diseases, highlighting the bidirectional biological mechanisms connecting periradicular pathologies and systemic conditions. Studies discussed in the article investigate the impact of oral infections on systemic diseases like diabetes mellitus, hypertension, and cardiovascular disease, emphasizing the potential influence of these conditions on the success of endodontic treatments. Researchers also examine the association between apical periodontitis and atherosclerotic cardiovascular disease, suggesting a possible link between periradicular diseases and systemic health. The findings underscore the importance of understanding the biological foundations of endodontics and the overall health of patients to provide comprehensive care. [Extracted from the article]

This study evaluated the shaping ability of XP‐endo Shaper and Mtwo systems in long‐oval‐shaped canals of extracted human mandibular molars using micro‐computed tomography (micro‐CT). Images recorded before and after preparation were evaluated for morphometric measures regarding increase in canal volume, dentin removed, surface area, untouched walls and structure model index (SMI). Data were statistically analysed using the Mann–Whitney test with 5% of significance. On both groups, the root canal preparation significantly increased all analysed parameters (P > 0.05). There was no statistical difference between XP‐endo Shaper and Mtwo systems in the increase of the canal volume (30.50%–27.82%), in volume of dentin removed (2.77%–2.40%), in the increase of the canal surface area (11.30%–8.86%), in canal untouched surfaces (9.57%–8.51%) and in the SMI (2.59%–2.68%), respectively. XP‐endo Shaper and Mtwo systems showed similar shaping efficiency and were not able to completely prepare the walls of long‐oval‐shaped canals of extracted human mandibular molars. [ABSTRACT FROM AUTHOR]

The last several years have seen increasing interest in understanding cachexia, muscle wasting, and physical frailty across the broad spectrum of patients with cardiovascular illnesses. This interest originally started in the field of heart failure, but has recently been extended to other areas such as atrial fibrillation, coronary artery disease, peripheral artery disease as well as to patients after cardiac surgery or transcatheter aortic valve implantation. Tissue wasting and frailty are prevalent among many of the affected patients. The ageing process itself and concomitant cardiovascular illness decrease lean mass while fat mass is relatively preserved, making elderly patients particularly prone to develop wasting syndromes and frailty. The aim of this review is to provide an overview of the available knowledge of body wasting and physical frailty in patients with cardiovascular illness, particularly focussing on patients with heart failure in whom most of the available data have been gathered. In addition, mechanisms of wasting and possible therapeutic targets are discussed. [ABSTRACT FROM AUTHOR]

Background: Surgical residency training is a complex and costly task. Hospital economic health is dependent on different variables, but it is especially linked to the country macroeconomics that may be extremely fluctuating, especially in underdeveloped countries. This study analyzed the correlation between a single-center university hospital financial status and subjective perception of general surgery residents on program support and adequacy. Methods: We surveyed former residents that started general surgery residency program in a tertiary university hospital between 1999 and 2017. Individuals answered a questionnaire about the perception of the influence of the hospital´s financial status on training. Hospital´s financial status was estimated yearly by the current liquidity ratio (CLR) that measures whether or not a company has enough resources to meet its short-term obligations. Results: Two hundred and fifty-seven (96%) were still in surgical practice; 242 (93%) were satisfied with their residency training; 210 (78%) believed training was affected by financial status; 183 (68%) believed they were prepared for independent practice; 180 (67%) practiced in an academic environment; 146 (54%) felt the need to complete specialty training beyond residency; and 56 (21%) believed hospital financial status was adequate. The rate of positive or negative answers did not correlate with the current liquidity ratio, except for the need to complete specialty training that was indirectly related to CLR. Conclusions: University hospital financial status did not influence subjective perception of general surgery residents on training, program support and adequacy. [ABSTRACT FROM AUTHOR]

Neorickettsia helminthoeca (NH), the agent of salmon poisoning disease or canine neorickettiosis (CN), is a bacterial endosymbiont of the nematode Nanophyetus salmincola, and infections are spreading among specific fish‐eating mammalians. This article describes the pathologic and immunohistochemical findings associated with spontaneous NH‐induced infections in dogs from Southern Brazil. The principal pathologic findings were hypertrophy of Peyer patches and lymphadenopathy with lymphocytic proliferation, chronic interstitial pneumonia, and chronic enteritis associated with positive intralesional immunoreactivity to antigens of NH within macrophages and histiocytes. Positive immunoreactivity against canine parvovirus‐2 (CPV‐2) or/and canine distemper virus was not detected in the evaluated intestinal segments or in the samples from the cerebellum and lungs, respectively, from the dogs evaluated. These findings demonstrated that NH was involved in the enteric, pulmonary, and lymphoid lesions herein described, and provide additional information to confirm the occurrence of this bacterial endosymbiont within this geographical location. It is proposed that chronic pneumonia should be considered as a pathologic manifestation of NH‐induced infections. Additionally, our results show that the occurrences of CN seem to be underdiagnosed in Southern Brazil due to the confusion with the incidence of CPV‐2. [ABSTRACT FROM AUTHOR]

Aims: We studied the association between android (A) to gynoid (G) fat ratio and functional capacity (peak VO2) in male patients with heart failure with reduced ejection fraction (HFrEF). Methods and results: We enrolled 118 male patients with HFrEF with left ventricular ejection fraction (LVEF) <40%. Body composition (by using dual x‐ray absorptiometry) and peak VO2 (by cardiopulmonary exercise testing) were measured. Sarcopenic obesity was defined according to the Foundation for the National Institutes of Health criteria (FNIH). Blood sample for metabolic and hormonal parameters were measured. Fifteen patients (12.7%) showed sarcopenic obesity (body mass index > 25 kg/m2 with FNIH index < 0.789). The median A/G ratio was 0.55. A/G ratio > 0.55 was detected in 60 patients. Relative peak VO2 was lower in patients with A/G ratio > 0.55 than in patients with A/G ratio <0.55 (18.7 ± 5.3 vs. 22.5 ± 6.1 mL/kg/min, P < 0.001). Logistic regression analysis showed A/G ratio >0.55 to be independently associated with reduced peak VO2 adjusted for age, body mass index, LVEF, presence of sarcopenia, anabolic hormones, and haemoglobin (odds ratio 3.895, 95% confidence interval 1.030–14.730, P = 0.045). Conclusions: Body fat distribution, particularly android and gynoid fat composition, together with other cofactors, might have an important adverse role on functional capacity in male patients with HFrEF. Future studies are needed to address possible mechanisms involved in this relationship. [ABSTRACT FROM AUTHOR]

Benzothiazole derivatives are highly selective and an antitumor therapeutic in vitro and in vivo, highlighting the compound 2‐ (4′‐aminophenyl) benzothiazole (ABT), which exhibits nanomolar concentration activity in vitro against some human breast cancer cells in humans. In this work, we designed new contrast agents based on the structural modification of ABT by complexing them with manganese in order to obtain paramagnetic complexes for efficient diagnosis of breast cancer. The new agents were evaluated by docking studies that allowed investigating interactions and the mode of connection between the active site of the enzyme and the compounds studied. The theoretical and experimental results both indicate that Compound 57 is a promising contrast agent. The novel 2‐ (4′‐aminophenyl) benzothiazole derivatives (ABT) were evaluated by docking studies, the compound 57 was selected as the most active compound and thus synthesized and characterized by 1 HNMR, 13 CNMR and MS. Tests were performed to evaluate cell viability, demonstrating that said compound have antiproliferative activity on the MCF‐7 lineage. Thus, compound may be useful both in the diagnosis and in the antitumor agent. [ABSTRACT FROM AUTHOR]

Disturbed shear rate (SR), characterized by increased retrograde and oscillatory SR in the brachial artery, is associated with inflammation, atherosclerosis, endothelial dysfunction, and sympathetic hyperactivity. Young subjects do not have disturbed SR; however, elderly subjects do, which seems to be associated with sympathetic hyperactivity. Anabolic androgenic steroids (AAS) abuse in young is associated with increased muscle sympathetic nerve activity (MSNA). We hypothesized that AAS users might have disturbed SR. We tested the association between retrograde and oscillatory SR with MSNA. In addition, we measured the high‐sensitivity C‐reactive protein (hs‐CRP). We evaluated 10 male AAS users, age 27 ± 4 years, and 10 age‐matched AAS nonusers, age 29 ± 5 years. At rest, retrograde and oscillatory SR were evaluated by Doppler ultrasound, MSNA was measured with microneurography, and hs‐CRP was measured in blood sample. Flow‐mediated dilation (FMD) was also assessed. AAS users had higher retrograde SR (24.42 ± 17.25 vs 9.15 ± 6.62 s−1, P = 0.01), oscillatory SR (0.22 ± 0.13 vs 0.09 ± 0.07 au P = 0.01), and MSNA (42 ± 9 vs 32 ± 4 bursts/100 heart beats, P = 0.018) than nonusers. MSNA (bursts/100 heart beats) was correlated with retrograde SR (r = 0.50, P = 0.050) and oscillatory SR (r = 0.51, P = 0.042). AAS users had higher hs‐CRP [1.17 (0.44‐3.63) vs 0.29 (0.17‐0.70) mg/L, P = 0.015] and decreased FMD (6.42 ± 2.07 vs 8.28% ± 1.53%, P = 0.035) than nonusers. In conclusion, AAS abuse is associated with retrograde and oscillatory SR which were associated with augmented sympathetic outflow. In addition, AAS seems to lead to inflammation characterized by increased hs‐CRP. These alterations may have the potential of increasing the early risk of atherosclerotic disease in young AAS users. [ABSTRACT FROM AUTHOR]

Seventeen new synthetic derivatives of eugenol (6, 8–15 and 8′‐15′) were planned following literature reports on antifungal activities of nitroeugenol and eugenol glucoside. The anti‐Candida activity of these compounds was investigated by in vitro assay, and the cytotoxicity evaluation was performed with the most active compounds. The peracetylated glucosides presented better biological results than their hydroxylated analogues. The glucoside 11, a 4‐nitrobenzamide, showed the best potency (MIC50 range 11.0–151.84 μ m), the wider spectrum of action, and overall the best selectivity indexes, especially against C. tropicalis (~30) and C. krusei (~15). To investigate its possible mechanism of action, glucoside 11 was subjected to molecular docking studies with Candida sp. enzymes involved in ergosterol biosynthesis. Results have shown that the peracetyl glucosyl moiety and the 4‐nitrobenzamide group in 11 are effectively involved in its high affinity with the active site of squalene epoxidase. [ABSTRACT FROM AUTHOR]

Background: In oral squamous cell carcinoma (OSCC), the HIF-1 complex promotes the expression of genes involved in specific mechanisms of cell survival under hypoxic conditions, such as plasminogen activator inhibitor-1 (PAI-1), carbonic anhydrase 9 (CAIX), and vascular endothelial growth factor A (VEGFA). The study aimed to investigate the presence and prognostic value of PAI-1, CAIX, and VEGFA in OSCC.Materials and Methods: Immunohistochemistry was used to analyze the expressions of these proteins in 52 tumoral tissue samples of patients with OSCC, surgically treated and followed by a minimum of 24 months after surgery. The correlations between protein expressions and clinicopathological parameters and prognosis were analyzed.Results: Positive PAI-1 membrane expression was significantly associated with local disease relapse (P = .027). Multivariate analysis revealed that the positive PAI-1 membrane expression is an independent marker for local disease relapse, with approximately 14-fold increased risk when compared to negative expression (OR = 14.49; CI = 1.40-150.01, P = .025). Strong PAI-1 cytoplasmic expression was significantly associated with the less differentiation grade (P = .027). Strong CAIX membrane expression was significantly associated with local disease-free survival (P = .038). Positive CAIX cytoplasmic expression was significantly associated with lymph node affected (P = .025) and with disease-specific survival (P = .022). Multivariate analysis revealed that the positive CAIX cytoplasmic expression is an independent risk factor for disease-related death, increasing their risk approximately 3-fold when compared to negative expression (HR = 2.84; CI = 1.02-7.87, P = .045). Positive VEGFA cytoplasmic expression was significantly associated with less differentiation grade (P = .035).Conclusion: Our results suggest a potential role for these expressions profiles as tumor prognostic markers in OSCC patients. [ABSTRACT FROM AUTHOR]

Abstract: Aims: We aimed to assess determinants of anorexia, that is loss of appetite in patients with heart failure (HF) and aimed to further elucidate the association between anorexia, functional capacity, and outcomes in affected patients. Methods and results: We assessed anorexia status among 166 patients with HF (25 female, 66 ± 12 years) who participated in the Studies Investigating Co‐morbidities Aggravating HF. Anorexia was assessed by a 6‐point Likert scale (ranging from 0 to 5), wherein values ≥1 indicate anorexia. Functional capacity was assessed as peak oxygen uptake (peak VO2), 6 min walk test, and short physical performance battery test. A total of 57 patients (34%) reported any anorexia, and these patients showed lower values of peak VO2, 6 min walk distance, and short physical performance battery score (all P < 0.05). Using multivariate analysis adjusting for clinically important factors, only high‐sensitivity C‐reactive protein [odds ratio (OR) 1.24, P = 0.04], use of loop diuretics (OR 5.76, P = 0.03), and the presence of cachexia (OR 2.53, P = 0.04) remained independent predictors of anorexia. A total of 22 patients (13%) died during a mean follow‐up of 22.5 ± 5.1 months. Kaplan‐Meier curves for cumulative survival showed that those patients with anorexia presented higher mortality (Log‐rank test P = 0.03). Conclusions: Inflammation, use of loop diuretics, and cachexia are associated with an increased likelihood of anorexia in patients with HF, and patients with anorexia showed impaired functional capacity and poor outcomes. [ABSTRACT FROM AUTHOR]

Citrus variegated chlorosis is a disease that attacks economically important citrus plantations and is caused by the plant-pathogenic bacterium Xylella fastidiosa. In this work, the structure of a small heat-shock protein from X. fastidiosa (XfsHSP17.9) is reported. The high-order structures of small heat-shock proteins from other organisms are arranged in the forms of double-disc, hollow-sphere or spherical assemblies. Unexpectedly, the structure reported here reveals a high-order architecture forming a nearly square cavity. [ABSTRACT FROM AUTHOR]

Patients under hemodialysis present protein-energy wasting (PEW), which is related with higher mortality rates. The study aimed to determine whether intradialytic resistance exercise training could improve physical performance, physical activity, and PEW in hemodialysis patients. In single center study, 75 hemodialysis patients were enrolled in an intradialytic resistance exercise training consisting of 20 min of adapted leg press, with a gymnastic ball, 3 days/week, during 9 months on the same day of hemodialysis therapy. Physical performance by short physical performance battery (SPPB), physical activity by life space assessment (LSA), and PEW score based on the nomenclature proposed by the International Society of Renal Nutrition and Metabolism in 2008 were assessed at baseline and after 9 months. Intradialytic resistance exercise training significantly improved SPPB score, LSA score, and PEW score (all, P < 0.05). In addition, intradialytic resistance exercise training improved SPPB score in patients with moderate and severe PEW subgroups ( P < 0.05), associated with reduced prevalence of the patients with moderate to severe PEW (53% vs. 36%, P < 0.05). Intradialytic resistance exercise training was safe and effective to improve physical performance, physical activity, and PEW in hemodialysis patients. [ABSTRACT FROM AUTHOR]

In this paper, the Galerkin method is used to obtain approximate solutions for Kirchhoff plates stochastic bending problem with uncertainty over plates flexural rigidity coefficient. The uncertainty in the rigidity coefficient is represented by means of parameterized stochastic processes. A theorem of Lax-Milgram type, about existence and uniqueness of the theoretical solutions, is presented and used in selection of the approximate solution space. The Wiener-Askey scheme of generalized polynomials chaos (gPC) is used to model the stochastic behavior of the displacement solutions. The performance of the approximate Galerkin solution scheme developed herein is evaluated by comparing first and second order moments of the approximate solution with the same moments evaluated from Monte Carlo simulation. Rapid convergence of approximate Galerkin's solution to the first and second order moments is observed, for the problems studied herein. Results also show that using the developed Galerkin's scheme one gets adequate estimates for accrued probability function to a random variable generated by the stochastic process of displacement. [ABSTRACT FROM AUTHOR]

In this paper, the Galerkin method is used to obtain approximate solutions for Kirchhoff plates stochastic bending problem with uncertainty over plates flexural rigidity coefficient. The uncertainty in the rigidity coefficient is represented by means of parameterized stochastic processes. A theorem of Lax-Milgram type, about existence and uniqueness of the theoretical solutions, is presented and used in selection of the approximate solution space. The Wiener-Askey scheme of generalized polynomials chaos (gPC) is used to model the stochastic behavior of the displacement solutions. The performance of the approximate Galerkin solution scheme developed herein is evaluated by comparing first and second order moments of the approximate solution with the same moments evaluated from Monte Carlo simulation. Rapid convergence of approximate Galerkin's solution to the first and second order moments is observed, for the problems studied herein. Results also show that using the developed Galerkin's scheme one gets adequate estimates for accrued probability function to a random variable generated by the stochastic process of displacement. [ABSTRACT FROM AUTHOR]

The aim of this study was to make a comparative evaluation of the surface topography of the cervical third and tip of four different rotary systems, before and after being used 12 times, in resin blocks with simulated root canals with standardized 45° curvatures, and analyzed by scanning electronic microscopy (SEM). A total of 1,440 resin blocks with simulated root canals and standardized curvatures were used. The blocks were divided into four groups and prepared by the crown down technique according to the manufacturers' recommendations: Group 1 (G1)-K3®, Group 2 (G2)-Protaper Universal®, Group 3 (G3)-Twisted Files®, and Group 4 (G4)-Biorace®. After each preparation, the instruments were washed and autoclaved. A total of 24 instruments were selected, being three new instruments and three after having been used for the 12th time, from each group. These instruments were analyzed by SEM. To perform the evaluation, 24 micrographs were observed by 12 evaluators who attributed a score to the images according to a template. In the qualitative analysis of the cervical region and tip of new instruments, it was observe that the files of Groups G4 and G2 were the least rough and those of G1, the roughest. In the same manner, the cervical region of the instruments was qualitatively analyzed after the 12th time of using them, and there was no statistically significant difference at a level of 1% (ANOVA P < 0.01) between G2 and G4 as well as between G1 and G3. As regards the tip, it was observed that there was no statistically significant difference, at a level of 1%, between the groups: G1 and G3, G1 and G4, and between G3 and G4, and there was statistically significant difference at a level of 1%, between group G2 and the other groups, with G3 having the greatest roughness (ANOVA P < 0.01). Microsc. Res. Tech., 2013. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate whether there is any relationship between socioeconomic factors and mental depression, specifically in connection with family income and education. Our empirical model was estimated using the database of three National Household Sampling Surveys (1998, 2003, and 2008) and their special supplements on the health status of the Brazilian population. Analyses for men and women were conducted separately. Family income proved to be a protective factor against depression for both men and women. With regard to the effects of education, the estimates indicate that the maximum risk of depression occurs when women have approximately four years of schooling and men have about eight. Above these levels, the risk decreases as schooling years increase. [ABSTRACT FROM AUTHOR]

This paper studies the impact of HIV/AIDS on per capita income and education. It explores two channels on how HIV/AIDS affects income that have not been sufficiently stressed by previous literature: the reduction of the incentives to stay in school due to shorter expected longevity and the reduction in productivity of experienced workers. In the model, individuals live for three periods, may get infected in the second period, and with some probability die of AIDS before reaching the third period of their lives. Parents care for the welfare of the future generations so that they will maximize lifetime utility of their dynasty. The simulations predict that the most affected countries in Sub-Saharan Africa in the future will be, on average, 30% poorer than they would be without AIDS. Schooling will decline in some cases by 40%. These figures are dramatically reduced with widespread medical treatment, as it increases the survival probability and productivity of infected individuals. ( JEL O11, I12, C15, O55) [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate antiinflammatory activity of the methylene chloride extract of Morus nigra in animal models. Carrageenan-induced paw edema as well as fibrovascular tissue growth induced by s.c. cotton pellet implantation were used to investigate the antiinflammatory activity of Morus nigra extract (MnE) in rats. A HPLC fingerprint was used for phytochemical analysis of the extracts. The MnE at test doses of 100-300 mg/kg p.o. clearly demonstrated antiinflammatory effects by reduced paw edema induced by carragenan and significantly inhibited the formation of granulomatous tissue. In addition, chemical compounds isolated from Morus nigra, including betulinic acid, β-sitosterol and germanicol, may be responsible for the antiinflammatory effect of the extract. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The antiproliferative activity of two prenylated benzophenones isolated from Rheedia brasiliensis, the triprenylated garciniaphenone and the tetraprenylated benzophenone 7-epiclusianone, was investigated against human cancer cell lines. The antiproliferative activity on melanoma (UACC-62), breast (MCF-7), drug-resistant breast (NCI-ADR), lung/non-small cells (NCI460), ovarian (OVCAR 03), prostate (PC03), kidney (786-0), lung (NCI-460) and tongue (CRL-1624 and CRL-1623) cancer cells was determined using spectrophotometric quantification of the cellular protein content. The effect of these benzophenones on the activity of cathepsins B and G was also investigated. Garciniaphenone displayed cytostatic activity in all cell lines, whereas 7-epiclusianone showed a dose-dependent cytotoxic effect. The IC50 values for cell proliferation revealed that 7-epiclusianone is more active than garciniaphenone against most of the cell lines. Furthermore, the antiproliferative effects demonstrated by garciniaphenone and 7-epiclusianone were related to their cathepsin inhibiting properties. In conclusion, 7-epiclusianone is a promising naturally occurring agent which displays multiple inhibitory effects which may be working in concert to inhibit cancer cell proliferation in vitro. The putative pathway by which 7-epiclusianone affects cancer cell development may involve cathepsin inhibition. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

When the surfaces of two elastic bodies present relative motions under certain amount of contact pressure themechanical system can be unstable. Experiments conducted on elastic bodies in contact shown that the dynamic system is self-excited by the non-linear behavior of the friction forces. The main objective of this paper is to estimate the friction force using the vibrations signals, measured on a reciprocating wear testing machine, by the proposed non-linear signal analysis formulation. In the proposed formulation the system global output is the sum of two outputs produced by a linear path associated in parallel with a non-linear path. This last path is a non-linear model that represents the friction force. Since the linear path can be identified by traditional signal analysis, the non-linear function can be evaluated by the global input/output relationships. Validation tests are conducted in a tribological system composed by a sphere in contact with and a prismatic body, which has an imposed harmonic motion. The global output force is simultaneously measured by a piezoelectric and by a piezoresistive load cells. The sphere and prismatic body vibrations are measured by a laser Doppler vibrometer and by an accelerometer respectively. All signals are digitalized at the same time base and the data is transferred to a microcomputer. The non-linear signal analysis technique uses this data to identify the friction force. [ABSTRACT FROM AUTHOR]

The article presents a study about lupeol whose molecule is said to consist four six-membered rings and one five-membered ring, all fused in trans fashion. The structure of lupeol, showing the atom-numbering scheme is provided. It mentions the stabilization of the crystal packing by van der Waals interactions and intermolecular O-H...O hydrogen bonds.

Maize aldose reductase (AR) is a member of the aldo-keto reductase superfamily. In contrast to human AR, maize AR seems to prefer the conversion of sorbitol into glucose. The apoenzyme was crystallized in space group P212121, with unit-cell parameters a = 47.2, b = 54.5, c = 100.6 Å and one molecule in the asymmetric unit. Synchrotron X-ray diffraction data were collected and a final resolution limit of 2.0 Å was obtained after data reduction. Phasing was carried out by an automated molecular-replacement procedure and structural refinement is currently in progress. The refined structure is expected to shed light on the functional/enzymatic mechanism and the unusual activities of maize AR. [ABSTRACT FROM AUTHOR]

Single crystals of the phenyl­coumarin named mammeigin (or mammea A/AA cycle D) [systematic name: 5-hydroxy-8,8-dimethyl-6-(3-methyl­butanoyl)-4-phenyl-2 H,8 H-pyrano[2,3- f]chromen-2-one], C25H24O5, were obtained in the course of a chemotaxonomic study of the Guttiferae family. Mammeigin was extracted from the fruits of Kilmeyera pumila. The structure reveals an infinite three-dimensional network stabilized by non-classical inter­molecular hydrogen bonds. [ABSTRACT FROM AUTHOR]

The asymmetric unit of the title compound, C(6)H(9)N(2)OS(2)(+).HSO(4)(-).H(2)O, contains a heterocyclic cation, a hydrogen sulfate anion and a water molecule. There are strong hydrogen bonds between the hydrogen sulfate anions and water molecules, forming an infinite chain along the [010] direction, from which the cations are pendent. The steric, electronic and geometric features are compared with those of similar compounds. In this way, structural relationships are stated in terms of the influence of the sulfate group on the protonation of the heterocycle and on the tautomeric equilibrium in the solid state.