Clinical profile of Spanish hepatitisC virus-infected treatment-naïve patients with compensated cirrhosis in the CREST study

BACKGROUND AND AIM OF THE STUDY

There are still patients with hepatitisC in Spain who have yet to be diagnosed, but their clinical profile is unclear. In 2021, 21.93% of patients diagnosed had cirrhosis and were mostly treatment-naïve.

METHODS

This sub-analysis describes the clinical profile of the 60Spanish treatment-naïve patients with compensated cirrhosis who were included in the CREST study.

MAJOR RESULTS

Sixty percent of patients were male, median age 56years, and 33% had a history of drug use. Almost three-quarters (71.3%) had more than one comorbidity and 78.3% took concomitant medication. At treatment initiation, median platelet count was 139×103/μL and FibroScan® 17kPa. No virological failure was observed and no patient discontinued treatment due to adverse events. No clinically significant changes were noted during or after treatment in the median platelet, albumin, bilirubin, and transaminase levels.

CONCLUSIONS

Treatment with glecaprevir/pibrentasvir for 8weeks in this cohort of treatment-naïve patients with compensated cirrhosis in Spain was safe and effective. This information reinforces the use of this short antiviral regimen even when there is compensated cirrhosis, simplifying the approach to hepatitisC among those patients still to be diagnosed and treated in Spain.

Effect of substrate mismatch, orientation, and flexibility on heterogeneous ice nucleation

Heterogeneous nucleation is the main path to ice formation on Earth. The ice nucleating ability of a certain substrate is mainly determined by both molecular interactions and the structural mismatch between the ice and the substrate lattices. We focus on the latter factor using molecular simulations of the mW model. Quantifying the effect of structural mismatch alone is challenging due to its coupling with molecular interactions. To disentangle both the factors, we use a substrate composed of water molecules in such a way that any variation on the nucleation temperature can be exclusively ascribed to the structural mismatch. We find that a 1% increase in structural mismatch leads to a decrease of ∼4 K in the nucleation temperature. We also analyze the effect of orientation of the substrate with respect to the liquid. The three main ice orientations (basal, primary prism, and secondary prism) have a similar ice nucleating ability. We finally assess the effect of lattice flexibility by comparing substrates where molecules are immobile to others where a certain freedom to fluctuate around the lattice positions is allowed. Interestingly, we find that the latter type of substrate is more efficient in nucleating ice because it can adapt its structure to that of ice.

Beyond lectures and practical courses: Teaching pharmacology using imaginative pedagogical tools

Pharmacology has broadened its scope considerably in recent decades. Initially, it was of interest to chemists, doctors and pharmacists. In recent years, however, it has been incorporated into the teaching of biologists, molecular biologists, biotechnologists, chemical engineers and many health professionals, among others. Traditional teaching methods, such as lectures or laboratory work, have been superseded by the use of new pedagogical approaches to enable a better conceptualization and understanding of the discipline. In this article, we present several new methods that have been used in Spanish universities. Firstly, we describe a teaching network that has allowed the sharing of pedagogical innovations in Spanish universities. A European experience to improve prescribing safety is described in detail. The use of popular films and medical TV series in biomedical students shows how these audiovisual resources can be helpful in teaching pharmacology. The use of virtual worlds is detailed to introduce this new approach to teaching. The increasingly important area of the social aspects of pharmacology is also considered in two sections, one devoted to social pharmacology and the other to the use of learning based on social services to improve understanding of this important area. Finally, the use of Objective Structured Clinical Evaluation in pharmacology allows to know how this approach can help to better evaluate clinical pharmacology students. In conclusion, this article allows to know new pedagogical methods resources used in some Spanish universities that may help to improve the teaching of pharmacology.

Growth rate of CO2 and CH4 hydrates by means of molecular dynamics simulations

CO2 and CH4 hydrates are of great importance both from an energetic and from an environmental point of view. It is therefore highly relevant to quantify and understand the rate with which they grow. We use molecular dynamics simulations to shed light on the growth rate of these hydrates. We put the solid hydrate phase in contact with a guest aqueous solution in equilibrium with the pure guest phase and study the growth of both hydrates at 400 bars with temperature. We compare our results with previous calculations of the ice growth rate. We find a growth rate maximum as a function of the supercooling in all cases. The incorporation of guest molecules into the solid structure strongly decelerates hydrate growth. Consistently, ice grows faster than either hydrate and the CO2 hydrate grows faster than the CH4 one because of the higher solubility of CO2. We also quantify the molecular motion required to build the solids under study and find that the distance traveled by liquid molecules exceeds by orders of magnitude that advanced by any solid. Less molecular motion is needed in order for ice to grow as compared to the hydrates. Moreover, when temperature increases, more motion is needed for solid growth. Finally, we find a good agreement between our growth rate calculations and experiments of hydrate growth along the guest-solution interface. However, more work is needed to reconcile experiments of hydrate growth toward the solution among each other and with simulations.

Homogeneous nucleation rate of methane hydrate formation under experimental conditions from seeding simulations

In this work, we shall estimate via computer simulations the homogeneous nucleation rate for the methane hydrate at 400 bars for a supercooling of about 35 K. The TIP4P/ICE model and a Lennard-Jones center were used for water and methane, respectively. To estimate the nucleation rate, the seeding technique was employed. Clusters of the methane hydrate of different sizes were inserted into the aqueous phase of a two-phase gas-liquid equilibrium system at 260 K and 400 bars. Using these systems, we determined the size at which the cluster of the hydrate is critical (i.e., it has 50% probability of either growing or melting). Since nucleation rates estimated from the seeding technique are sensitive to the choice of the order parameter used to determine the size of the cluster of the solid, we considered several possibilities. We performed brute force simulations of an aqueous solution of methane in water in which the concentration of methane was several times higher than the equilibrium concentration (i.e., the solution was supersaturated). From brute force runs, we infer the value of the nucleation rate for this system rigorously. Subsequently, seeding runs were carried out for this system, and it was found that only two of the considered order parameters were able to reproduce the value of the nucleation rate obtained from brute force simulations. By using these two order parameters, we estimated the nucleation rate under experimental conditions (400 bars and 260 K) to be of the order of log₁₀ (J/(m³ s)) = -7(5).

Long-Term Outcome of Critically Ill Advanced Cancer Patients Managed in an Intermediate Care Unit

Background: To analyze the long-term outcomes for advanced cancer patients admitted to an intermediate care unit (ImCU), an analysis of a do not resuscitate orders (DNR) subgroup was made. Methods: A retrospective observational study was conducted from 2006 to January 2019 in a single academic medical center of cancer patients with stage IV disease who suffered acute severe complications. The Simplified Acute Physiology Score 3 (SAPS 3) was used as a prognostic and severity score. In-hospital mortality, 30-day mortality and survival after hospital discharge were calculated. Results: Two hundred and forty patients with stage IV cancer who attended at an ImCU were included. In total, 47.5% of the cohort had DNR orders. The two most frequent reasons for admission were sepsis (32.1%) and acute respiratory failure (excluding sepsis) (38.7%). Mortality in the ImCU was 10.8%. The mean predicted in-hospital mortality according to SAPS 3 was 51.9%. The observed in-hospital mortality was 37.5% (standard mortality ratio of 0.72). Patients discharged from hospital had a median survival of 81 (30.75−391.25) days (patients with DNR orders 46 days (19.5−92.25), patients without DNR orders 162 days (39.5−632)). The observed mortality was higher in patients with DNR orders: 52.6% vs. 23.8%, p 0 < 0.001. By multivariate logistic regression, a worse ECOG performance status (3−4 vs. 0−2), a higher SAPS 3 Score and DNR orders were associated with a higher in-hospital mortality. By multivariate analysis, non-invasive mechanical ventilation, higher bilirubin levels and DNR orders were significantly associated with 30-day mortality. Conclusion: For patients with advanced cancer disease, even those with DNR orders, who suffer from acute complications or require continuous monitoring, an ImCU-centered multidisciplinary management shows encouraging results in terms of observed-to-expected mortality ratios.

Homogeneous nucleation of NaCl in supersaturated solutions

The seeding method is an approximate approach to investigate nucleation that combines molecular dynamics simulations with classical nucleation theory. Recently, this technique has been successfully implemented in a broad range of nucleation studies. However, its accuracy is subject to the arbitrary choice of the order parameter threshold used to distinguish liquid-like from solid-like molecules. We revisit here the crystallization of NaCl from a supersaturated brine solution and show that consistency between seeding and rigorous methods, like Forward Flux Sampling (from previous work) or spontaneous crystallization (from this work), is achieved by following a mislabelling criterion to select such threshold (i.e. equaling the fraction of the mislabelled particles in the bulk parent and nucleating phases). This work supports the use of seeding to obtain fast and reasonably accurate nucleation rate estimates and the mislabelling criterion as one giving the relevant cluster size for classical nucleation theory in crystallization studies.

Recovery of parathyroid function in patients with thyroid cancer treated by total thyroidectomy: An analysis of 685 patients with hypoparathyroidism at discharge of surgery

OBJECTIVE

We aimed to study the predictive factors for recovery of parathyroid function in hypoparathyroid patients after total thyroidectomy for thyroid cancer.

METHODS

We designed a retrospective, multicentre and nation-wide analysis of patients with total thyroidectomy who were seen in twenty endocrinology departments from January to March 2018. We selected patients with histologically proven thyroid cancer and retrieved information related to surgical procedure and thyroid cancer features. Survival analysis and Cox regression analysis were used to study the relationship between these variables and the recovery of parathyroid function.

RESULTS

From 685 patients with hypoparathyroidism at discharge of surgery, 495 (72.3%) recovered parathyroid function over time. Kaplan-Meier analysis showed that this recovery was significantly related to the presence of specialized surgical team (P<0.001), identification of parathyroid glands at surgery (P<0.001), papillary histopathology (P=0.040), and higher levels of postoperative calcium (Ca) (P<0.001) and parathyroid hormone (PTH) (P<0.001). Subjects with gross extrathyroidal extension (P=0.040), lymph node metastases (P=0.004), and surgical re-intervention after initial surgery (P=0.024) exhibited a significant risk of persistence of hypoparathyroidism. Multivariate Cox regression analysis showed that the significant and independent factors for recovery of parathyroid function were postoperative concentrations of Ca (P=0.038) and PTH (P=0.049). The presence of lymph node metastases was a negative predictor of recuperation of parathyroid function (P=0.042) in this analysis.

CONCLUSION

In patients with thyroid cancer, recovery of parathyroid function after total thyroidectomy was directly related to postoperative Ca and PTH concentrations, and inversely related to lymph node metastases.

Mortality risk in cardiogenic shock depending on aetiology in a Mediterranean cohort. Prognostic accuracy of CardShock vs IABP score: the Shock CAT study

Background

Mortality in cardiogenic shock (CS) remains very high. Several risk scores have been purposed to early stratification, although the CS aetiology could influence in this prediction.

Purpose

The aim is to investigate in-hospital prognosis and mortality risk in CS patients depending on the CS aetiology comparing the prognostic accuracy of CardShock and IABP scores in a Mediterranean cohort.

Method

Shock CAT study was a multicentre, prospective, observational study conducted between December 2018 and December 2019 in eight public University hospitals in Catalonia (Spain), including CS patients due to acute coronary syndrome (ACS) and other aetiologies. Data on clinical presentation, biomarkers, management, including mechanical assistance support were analyzed comparing ACS and non-ACS patients. Cardshock and IABP score have been compared to assess 90-days mortality risk in both groups.

Results

A total of 382 CS patients were included, mean age was 65.3 (SD 13.9) years and 75.1% were men. Patient were classified in ACS (n=232, 60.7%) and non-ACS (n=150, 39.3%). In ACS group, 77.6% were STEMI, reperfussion in 84.7% of cases, all with primary angioplasty, 9% developed mechanical complications and 19.4% primary ventricular fibrillation. Main non-ACS aetiologies were severe heart failure (36.2%), malignant arrhythmias (22.1%), valve disease (8.0%) and myocarditis (7.4%). ACS group had less prevalence of women (17.7% vs 36%, p=0.001) and previous myocardial infarction (13.9% vs 24.8%, p=0.007). Mechanical assistance device was implanted more in ACS patients (43.1% vs 16.7%, p&lt;0.001, mainly intraaortic balloon pump (35.6% vs 9.8%, p&lt;0.001) and ECMO (10.7% vs 3%, p=0.01). Both shock risk scores were higher in ACS patients, Cardshock (4.5 vs 4.0, p=0.006) and IABP (2.4 vs 1.9, p=0.005). In-hospital mortality was higher in ACS (37.1 vs 26.7%, p=0.035) although this difference loss the significance at 90-days (40.9 vs 31.8%, p=0.074) and 6-months (45.2 vs 35.8%, p=0.176). Receiver-operating characteristic curves demonstrated that IABP shock score had superior prognostic power for predicting 90-days mortality when compared with Cardshock score in ACS patients (area under the curve -AUC- 0.74 vs 0.66) respectively, p=0.047, although both scores were similar in non-ACS (AUC 0.64 vs 0.62, p=0.693), Figures 1–2.

Conclusions

Cardiogenic shock due to ACS had higher in-hospital mortality than non-ACS CS, although this difference decreased at 90 days and 6 months. IABP score provided better 90-days mortality risk prediction than CardShock score in ACS patients, but both scores are similar in non-ACS cardiogenic shock.

Funding Acknowledgement

Type of funding sources: None. Figure 1Figure 2

Mortality risk in cardiogenic shock: head to head comparision CardShock vs IABP score in a Mediterranean cohort: the Shock CAT study

Background

Mortality in cardiogenic shock (CS) remains very high. Several risk scores have been purposed to early stratification.

Purpose

The aim is to investigate in-hospital prognosis and mortality risk in CS patients comparing the prognostic accuracy of CardShock and IABP scores in a Mediterranean cohort.

Method

Shock CAT study was a multicentre, prospective, observational study conducted between December 2018 and December 2019 in eight public University hospitals in Catalonia (Spain), including CS patients due to acute coronary syndrome (ACS) and other aetiologies. Data on clinical presentation, biomarkers, management, including mechanical assistance support were analyzed. Cardshock and IABP score have been compared to assess 90-days mortality risk in a Mediterranean cohort.

Results

A total of 382 CS patients were included, mean age was 65.3 (SD 13.9) years and 75.1% were men. The most common cause of CS was ACS (61%, n=233); of them, 77.6% were STEMI, 9% developed mechanical complications and 19.4% primary ventricular fibrillation. STEMI patients were reperfused in 84.7% of cases, all with primary angioplasty. Main non-ACS aetiologies were severe acute heart failure, malignant arrhythmias and myocarditis. Mechanical assistance device was implanted in one third of patients (n=119), mainly intraaortic balloon pump (26.1%), ECMO in 7.8% and Impella in 4.5%. Average Cardshock score was 4.3 (SD 1.74) and mean IABP score was 2.2 (SD 1.61). In-hospital mortality was 33% (126 patients) and 90-days mortality was 37.3% (141 patients). Receiver-operating characteristic curves demonstrated that IABP shock score had superior prognostic power for predicting 90-days mortality when compared with Cardshock score (area under the curve 0.72 vs 0.66) respectively, p=0.042; Figure 1.

Conclusions

Even though invasive management with STEMI reperfusion and mechanical assistance devices, cardiogenic shock in-hospital mortality remains 33% in a contemporary Mediterranean cohort. In this population, IABP shock score provided better 90-days mortality risk prediction than CardShock score

Funding Acknowledgement

Type of funding sources: None.

Late Recovery of Parathyroid Function After Total Thyroidectomy: A Case-Control Study

The clinical characteristics of patients with postoperative hypoparathyroidism who recover parathyroid function more than 12 months after surgery have not been studied. We aimed to evaluate whether the intensity of replacement therapy with calcium and calcitriol is related to the late recovery of parathyroid function. We compared the demographic, surgical, pathological, and analytical features of two groups of patients: cases, i. e., late recovery patients (those who recover parathyroid function>1 year after thyroidectomy, n=40), and controls, i. e., patients with permanent hypoparathyroidism (n=260). Replacement therapy with calcium and calcitriol was evaluated at discharge of surgery, 3-6 months, 12 months, and last visit. No significant differences were found in clinical, surgical, pathological, or analytical characteristics between cases and controls. The proportion of cases who required treatment with calcium plus calcitriol at 12 months was significantly lower than that found in controls (p<0.001). Furthermore, daily calcium and calcitriol doses in controls were significantly higher than those in cases at 3-6 months (p=0.014 and p=0.004, respectively) and at 12 months (p<0.001 and p=0.043, respectively). In several models of logistic regression analysis therapy with calcium and calcitriol at 12 months was negatively related to late recovery of parathyroid function. Although delayed recuperation of parathyroid function after total thyroidectomy is uncommon (13%), follow-up beyond 12 months is necessary in patients with postoperative hypoparathyroidism, especially in those whose needs of treatment with Ca and calcitriol are reducing over time.

Equivalence between condensation and boiling in a Lennard-Jones fluid

Condensation and boiling are phase transitions highly relevant to industry, geology, and atmospheric science. These phase transitions are initiated by the nucleation of a drop in a supersaturated vapor and of a bubble in an overstretched liquid, respectively. The surface tension between both phases, liquid and vapor, is a key parameter in the development of such nucleation stage. Whereas the surface tension can be readily measured for a flat interface, there are technical and conceptual limitations to obtain it for the curved interface of the nucleus. On the technical side, it is quite difficult to observe a critical nucleus in experiments. From a conceptual point of view, the interfacial free energy depends on the choice of the dividing surface, being the surface of tension the one relevant for nucleation. We bypass the technical limitation by performing simulations of a Lennard-Jones fluid where we equilibrate critical nuclei (both drops and bubbles). Regarding the conceptual hurdle, we find the relevant cluster size by searching the radius that correctly predicts nucleation rates and nucleation free energy barriers when combined with Classical Nucleation Theory. With such definition of the cluster size we find the same value of the surface tension for drops and bubbles of a given radius. Thus, condensation and boiling can be viewed as two sides of the same coin. Finally, we combine the data coming from drops and bubbles to obtain, via two different routes, estimates of the Tolman length, a parameter that allows describing the curvature dependence of the surface tension in a theoretical framework.

Permanent postoperative hypoparathyroidism: an analysis of prevalence and predictive factors for adequacy of control in a cohort of 260 patients

Background

Recent guidelines for the treatment of hypoparathyroidism emphasize the need for long-term disease control, avoiding symptoms and hypocalcaemia. Our aim has been to analyze the prevalence of poor disease control in a national cohort of patients with hypoparathyroidism, as well as to evaluate predictive variables of inadequate disease control.

Methods

From a nation-wide observational study including a cohort of 1792 patients undergoing total thyroidectomy, we selected 260 subjects [207 women and 53 men, aged (mean ± SD) 47.2±14.8 years] diagnosed with permanent hypoparathyroidism. In every patient demographic data and details on surgical procedure, histopathology, calcium (Ca) metabolism, and therapy with Ca and calcitriol were retrospectively collected. A patient was considered not adequately controlled (NAC) if presented symptoms of hypocalcemia or biochemical data showing low serum Ca levels or high urinary Ca excretion.

Results

Two hundred and twenty-one (85.0%) patients were adequately controlled (AC) and 39 (15.0%) were NAC. Comparison between AC and NAC patients did not show any significant difference in demographic, surgical, and pathological features. Rate of hospitalization during follow-up was significantly higher among NAC patients in comparison with AC patients (35.9% vs. 10.9%, P<0.001). Dose of oral Ca and calcitriol were also significantly higher in NAC subjects. In a subgroup of 129 patients with serum parathyroid hormone (PTH) levels available, we found that NAC patients exhibited significantly lower postoperative PTH concentrations than AC patients [median (interquartile range) 3 (1.9-7.8) vs. 6.9 (3.0-11) pg/mL; P=0.009].

Conclusions

In a nation-wide cohort of 260 subjects with definitive hypoparathyroidism, 15% of them had poor disease control. These patients required higher doses of oral Ca and calcitriol, had higher rate of hospitalization during follow-up and showed lower PTH concentrations in the postoperative period.

[COVID-19 Pandemic: Impact and rapid reaction of Urology]

The COVID-19 pandemic caused by the SARS-CoV-2 virus has caused tens of thousands of deaths in Spain and has managed to breakdown the healthcare system hospitals in the Community of Madrid, largely due to its tendency to cause severe pneumonia, requiring ventilatory support. This fact has caused our center to collapse, with 130% of its beds occupied by COVID-19 patients, thus causing the absolute cessation of activity of the urology service, the practical disappearance of resident training programs, and the incorporation of a good part of the urology staff into the group of medical personnel attending these patients. In order to recover from this extraordinary level of suspended activity, we will be obliged to prioritize pathologies based on purely clinical criteria, for which tables including the relevance of each pathology within each area of urology are being proposed. Technology tools such as online training courses or surgical simulators may be convenient for the necessary reestablishment of resident education.

Necesidades de información en las empresas: estudio de un caso

El estudio de las necesidades de información en las empresas es una tarea compleja y urgente que se está acometiendo desde distintas vertientes, con el fin de ir completando el conocimiento que se tiene de este tipo de usuario de información. En este sentido, en el trabajo se estudian las necesidades de información de las empresas norteamericanas del estado de Indiana, a partir de una serie de entrevistas con responsables de centros de información y servicios de desarrollo, que atendían las distintas demandas de las empresas. Asimismo, en el trabajo se ha utilizado una encuesta realizada por la Universidad del Estado de Indiana sobre el uso y los tipos de información más demandados por las empresas.

Seeding approach to nucleation in the NVT ensemble: The case of bubble cavitation in overstretched Lennard Jones fluids

Simulations are widely used to study nucleation in first order phase transitions due to the fact that they have access to the relevant length and time scales. However, simulations face the problem that nucleation is an activated process. Therefore, rare event simulation techniques are needed to promote the formation of the critical nucleus. The Seeding method, where the simulations are started with the nucleus already formed, has proven quite useful in efficiently providing estimates of the nucleation rate for a wide range of orders of magnitude. So far, Seeding has been employed in the NPT ensemble, where the nucleus either grows or redissolves. Thus, several trajectories have to be run in order to find the thermodynamic conditions that make the seeded nucleus critical. Moreover, the nucleus lifetime is short and the statistics for obtaining its properties is consequently poor. To deal with these shortcomings we extend the Seeding method to the NVT ensemble. We focus on the problem of bubble nucleation in a metastable Lennard Jones fluid. We show that, in the NVT ensemble, it is possible to equilibrate and stabilise critical bubbles for a long time. The nucleation rate inferred from NVT-Seeding is fully consistent with that coming from NPT-Seeding. The former is quite suitable to obtain the nucleation rate along isotherms, whereas the latter is preferable if the dependence of the rate with temperature at constant pressure is required. Care should be taken with finite size effects when using NVT-Seeding. Further work is required to extend NVT seeding to other sorts of phase transitions.

Seeding approach to bubble nucleation in superheated Lennard-Jones fluids

We investigate vapor homogeneous nucleation in a superheated Lennard-Jones liquid with computer simulations. Special simulation techniques are required to address this study since the nucleation of a critical vapor bubble-one that has an equal chance to grow or shrink-in a moderately superheated liquid is a rare event. We use the Seeding method, which combines Classical Nucleation Theory with computer simulations of a liquid containing a vapor bubble to provide bubble nucleation rates in a wide temperature range. Seeding has been successfully applied to investigate the nucleation of crystals in supercooled fluids, and here we apply it to the liquid-to-vapor transition. We find that the Seeding method provides nucleation rates that are consistent with independent calculations not based on the assumptions of Classical Nucleation Theory. Different criteria to determine the radius of the critical bubble give different rate values. The accuracy of each criterion depends of the degree of superheating. Moreover, seeding simulations show that the surface tension depends on pressure for a given temperature. Therefore, using Classical Nucleation Theory with the coexistence surface tension does not provide good estimates of the nucleation rate.

Prevalence and risk factors for hypoparathyroidism following total thyroidectomy in Spain: a multicentric and nation-wide retrospective analysis

PURPOSE

The prevalence of postoperative hypoparathyroidism has been studied in registries and in surgical series with highly variable and imprecise results. However, the frequency of this hormonal deficiency in the clinical practice of endocrinologists is not known with accuracy. We aimed to assess the prevalence and risk factors of hypoparathyroidism in patients undergoing total thyroidectomy in Spain.

METHODS

We designed a retrospective, multicentre and nation-wide protocol including all patients with total thyroidectomy who were seen in the endocrinology clinic of the participant centers from January to March 2018. Prevalence of hypoparathyroidism was evaluated at discharge of surgery, 3-6 months after surgery, 12 months after surgery and at last visit. Twenty hospitals participated in the study.

RESULTS

Of 1792 patients undergoing total thyroidectomy, 866 (48.3%) developed postoperative hypoparathyroidism at discharge of surgery. Most of them recover parathyroid function over time. Prevalence of hypoparathyroidism at 3-6 months, 12 months and at last visit was 22.9%, 16.7% and 14.5%, respectively. The risk of developing definitive hypoparathyroidism was related to the presence of parathyroid tissue at histology, lymph node dissection, and two-stage thyroidectomy. Patients with thyroid cancer, with higher postoperative calcium levels and treated by expert surgical teams exhibited lower risk of developing permanent hypoparathyroidism.

CONCLUSIONS

Although most patients with postsurgical hypoparathyroidism recover parathyroid function, the prevalence of permanent disease in clinical practice is non negligible (14.5%). Postoperative calcium, extent and timing of surgery, the presence of cancer, expert surgical team, and parathyroid tissue at histology are predictors of permanent hypoparathyroidism.

Correction to: Prevalence and risk factors for hypoparathyroidism following total thyroidectomy in Spain: a multicentric and nation-wide retrospective analysis

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

On the time required to freeze water

By using the seeding technique the nucleation rate for the formation of ice at room pressure will be estimated for the TIP4P/ICE model using longer runs and a smaller grid of temperatures than in the previous work. The growth rate of ice will be determined for TIP4P/ICE and for the mW model of water. Although TIP4P/ICE and mW have a similar melting point and melting enthalpy, they differ significantly in the dynamics of freezing. The nucleation rate of mW is lower than that of TIP4P/ICE due to its higher interfacial free energy. Experimental results for the nucleation rate of ice are between the predictions of these two models when obtained from the seeding technique, although closer to the predictions of TIP4P/ICE. The growth rate of ice for the mW model is four orders of magnitude larger than for TIP4P/ICE. Avrami's expression is used to estimate the crystallization time from the values of the nucleation and growth rates. For mW the minimum in the crystallization time is found at approximately 85 K below the melting point and its value is of about a few ns, in agreement with the results obtained from brute force simulations by Moore and Molinero. For the TIP4P/ICE the minimum is found at about 55 K below the melting point, but its value is about ten microseconds. This value is compatible with the minimum cooling rate required to avoid the formation of ice and obtaining a glass phase. The crossover from the nucleation controlled crystallization to the growth controlled crystallization will be discussed for systems of finite size. This crossover could explain the apparent discrepancy between the values of J obtained by different experimental groups for temperatures below 230 K and should be considered as an alternative hypothesis to the two previously suggested: internal pressure and/or surface freezing effects. A maximum in the compressibility was found for the TIP4P/ICE model in supercooled water. The relaxation time is much smaller than the crystallization time at the temperature at which this maximum occurs, so this maximum is a real thermodynamic feature of the model. At the temperature of minimum crystallization time, the crystallization time is larger than the relaxation time by just two orders of magnitude.

The function of national journals in disseminating applied science

This paper considers the problem of national versus inter national journals. The practice in certain countries of giving 'recognition' only to Science Citation Index journals, per se, does a disservice to national journals. These journals serve an important role in local diffusion of applied infor mation. Sixty papers were studied: half published in a local Spanish journal and the other half in international journals. They were written by the same groups of researchers. Indicators designed to discriminate the type of research published in both sets were used. The analysis indicated that the type of research published in the Spanish journals is applied, whereas that published abroad is basic. Apparently, the Spanish journal is nearer to the industrial sector. However, to disregard the local journal for evalua tive purposes may be a disservice to scientists who are trying to help in the transfer of information to the indus trial sector.

The mold integration method for the calculation of the crystal-fluid interfacial free energy from simulations

The interfacial free energy between a crystal and a fluid, γcf, is a highly relevant parameter in phenomena such as wetting or crystal nucleation and growth. Due to the difficulty of measuring γcf experimentally, computer simulations are often used to study the crystal-fluid interface. Here, we present a novel simulation methodology for the calculation of γcf. The methodology consists in using a mold composed of potential energy wells to induce the formation of a crystal slab in the fluid at coexistence conditions. This induction is done along a reversible pathway along which the free energy difference between the initial and the final states is obtained by means of thermodynamic integration. The structure of the mold is given by that of the crystal lattice planes, which allows to easily obtain the free energy for different crystal orientations. The method is validated by calculating γcf for previously studied systems, namely, the hard spheres and the Lennard-Jones systems. Our results for the latter show that the method is accurate enough to deal with the anisotropy of γcf with respect to the crystal orientation. We also calculate γcf for a recently proposed continuous version of the hard sphere potential and obtain the same γcf as for the pure hard sphere system. The method can be implemented both in Monte Carlo and Molecular Dynamics. In fact, we show that it can be easily used in combination with the popular Molecular Dynamics package GROMACS.

Field-induced sublimation in perfect two-dimensional colloidal crystals

Phase transitions in two-dimensional (2D) systems are of considerable fundamental and practical importance. However, the kinetics of these processes are difficult to predict and understand, even in simple systems for which equilibrium states are properly described, owing to the difficulty of studying crystallites with single-particle resolution and free of defects. Here we introduce an alternative method for the sublimation of 2D colloidal crystallites by a sudden induction of repulsive forces between the particles. The sublimation kinetics, studied in real space by microscopy and by computer simulations, shows a scaling behavior that suggests a universal mechanism fundamentally different from the one usually accepted for thermal sublimation. The universal behavior found for the early stages of the process may be useful for understanding the dynamic features of particle systems at liquid interfaces and for designing technological applications without the need of performing extensive experimental studies.

[Steps towards the institutionalization of health impact assessment in Spain: perception of public health professionals]

BACKGROUND

The current normative reform of public health policy in Spain envisages the inclusion of Health Impact Assessment (HIA). This study contributes the vision of public health and planning professionals on the usefulness and applicability of HIA in their daily work and thus reflects on how best to institutionalize it.

METHODOLOGY

Three training workshop were carried out with public health professionals. Participants were specialists in different branches: epidemiological surveillance, environmental health, food safety and health promotion. In this HIA workshop, a questionnaire was given to the attendees to be completed.

RESULTS

Forty-one percent of the people attending answered the questionnaire; 92% of the staff considered that the model of social determinants of health is useful in the field of public health. The principal routes for introducing HIA were: mandatory rules (85%), integration into other existing assessment tools (65%) and the systematization of this methodology (40%). Concerning the applicability of HIA, specific strategies ere proposed for its introduction into the different branches of public health.

CONCLUSIONS

The successful institutionalization of HIA will require the opinion and collaboration of the technical personnel. A widespread approval of this tool for its utilization in the administration was verified. To guarantee the viability of its implementation, it will be necessary to raise the awareness of professionals about the model of the social determinants of health, as well as to attend to their demands and suggestions.

Cytological features of ossifying fibromyxoid tumor of soft parts

A case of ossifying fibromyxoid tumor (OFMT) evaluated during an intraoperative pathological consultation is presented. The patient, a 70-year-old woman was being followed because of a tumor in the left buttock. Cytological smears were obtained after scrapping the tumoral cut surface and revealed a myxoid background with fragments composed of a denser, fibrillar metachromatic stroma with accompanying round to oval tumoral nuclei and no vessels. Single cells were predominantly monomorphic with a round to oval morphology and scarce cytoplasm. The most relevant feature of the tumor was its peripheral, plaque-like, calcified consistency. The review of the cytological descriptions of four cases revealed similar findings that can be presumed as those of a low-grade myxoid tumor of round to oval cells. A specific recognition of OFMT based solely on cytological features seems difficult. However, when such features are coupled with characteristic radiological findings (peripheral calcification) this entity must be considered.

Claves educativas para aumentar la motivación de los jóvenes físicamente inactivos

El presente estudio pretende averiguar, por una parte, cuáles son las razones que llevan a los jóvenes a abandonar la práctica físico-deportiva y, por otra, descubrir por qué algunos jóvenes nunca se iniciaron en este tipo de experiencias, con el fin de establecer una filosofía educativa que envuelva la práctica físico-deportiva del joven y optimice tanto su inicio como su mantenimiento en dicho estilo de vida. La investigación se apoya en una triangulación metodológica con técnicas cuantitativas, como el análisis descriptivo de los datos recogidos a través de un cuestionario y cualitativas, como el análisis de contenido de cuatro grupos de discusión. El escaso interés se establece como la principal barrera para iniciarse o mantenerse en la práctica físico-deportiva tanto en los estudiantes de Educación Secundaria Obligatoria (ESO) como en los universitarios. Ante esto se proponen determinadas claves educativas, a tener en cuenta desde edades tempranas, para aumentar la motivación en la población, en general, y en los jóvenes físicamente inactivos, en particular.

Pedagogía de la convivencia y educación no formal: un estudio desde el ocio físico-deportivo, los valores y la familia

El ser humano se concibe en una constante interrelación con variados agentes educativos de los que fluyen diversos valores y actitudes. El presente estudio pretende verificar la idoneidad del ocio físico-deportivo para el fomento de valores sociales dirigidos a optimizar la sociabilidad y la convivencia de los adolescentes considerándose, asimismo, a la familia como agente cardinal de este proceso. Se ha explorado la percepción que jóvenes, padres y profesores tienen sobre la dimensión social de los valores en el ámbito de análisis. Para tal fin se ha utilizado una complementariedad metodológica trabajando con técnicas cuantitativas -empleando como instrumento de medida un cuestionario- y con técnicas cualitativas -caso del análisis de contenido de cuatro grupos de discusión-. Los resultados ratifican que el ocio físico-deportivo es, a priori, un contexto axiológico neutro, que posee el potencial de fomentar tanto valores como contravalores; que la familia se constituye en un agente educativo fundamental susceptible de condicionar el hábito físico-deportivo del adolescente; por último, a pesar de que los padres defienden una práctica promotora de valores sociales, los profesores y los jóvenes les reprochan el hecho de no valorarla en su justa medida facilitándose, de este modo, el abandono de dicho estilo de vida.

Crystallization and aging in hard-sphere glasses

We report new results from our programme of molecular dynamics simulation of hard-sphere systems, focusing on crystallization and glass formation at high concentrations. First we consider a much larger system than hitherto, N = 86 400 equal-sized particles. The results are similar to those obtained with a smaller system, studied previously, showing conventional nucleation and growth of crystals at concentrations near melting and crossing over to a spinodal-like regime at higher concentrations where the free energy barrier to nucleation appears to be negligible. Second, we investigate the dependence on the initial state of the system. We have devised a Monte Carlo 'constrained aging' method to move the particles in such a way that crystallization is discouraged. After a period of such aging, the standard molecular dynamics programme is run. For a system of N = 3200, we find that constrained aging encourages caging of the particles and slows crystallization somewhat. Nevertheless, both aged and unaged systems crystallize at volume fraction φ = 0.61 whereas neither system shows full crystallization in the duration of the simulation at φ = 0.62, a concentration still significantly below that of random close packing.

Patterns of corpora lutea growth and progesterone secretion in sows with thrifty genotype and leptin resistance due to leptin receptor gene polymorphisms (Iberian pig)

The current study aimed to compare luteal function, as measured by corpora lutea dynamics and progesterone secretion, in 10 sows with obesity/leptin resistance genotype (Iberian pig) and 10 females of lean commercial crosses (Large White × Landrace). In all the animals, the oestrous cycle was synchronized with progestagens, and ovulation was induced by exogenous gonadotrophins. Thereafter, number and size of follicles and plasma oestradiol concentration were determined at oestrus detection, and number and size of corpora lutea and progesterone concentration were evaluated from Day 4 to 12 of the cycle. There were no differences between genotypes in follicle population and oestradiol concentration, and ovulation rate (15.2±1.3 in Iberian vs 12.7±1.8 in LWxL sows); however, there was a higher percentage of Iberian than control sows showing luteal cysts (66.7% vs 30%, respectively; p<0.05). In both breeds, both total luteal area and plasma progesterone concentration grew linearly from Day 4 to 8 (p<0.01) and remained more stable between Days 8 and 12, without significant differences between genotypes. In conclusion, current study supports that ovulatory processes and luteal functionality are not the main limiting factors for prolificacy in a pig model of leptin resistance and obesity.

Preovulatory follicle dynamics and ovulatory efficiency in sows with thrifty genotype and leptin resistance due to leptin receptor gene polymorphisms (Iberian pig)

This study compares follicular function and ovulatory efficiency in 20 sows with obesity/leptin resistance genotype (Iberian pig) and 20 females of lean commercial crosses (Large White × Landrace; LW×L). Estrous cycle was synchronized with progestagens; ovulation was induced with eCG and hCG, in half of the females of each group, to determine its effect. In females of both breeds not treated with gonadotropins, the number of follicles larger than 4.9 mm and the estradiol secretion increased throughout the follicular phase (P<0.05); estradiol values were similar at estrus detection (22.5±1.2 vs. 26.5±0.6 pg/ml respectively, for Iberian and LW×L sows). Moreover, ovulation rate was higher in Iberian pigs (15.3±1.3 CLs) than in LW×L (10.2±1.3 CLs; P<0.05), with mean progesterone values being 18.1±0.7 ng/ml in Iberian and 16.8±0.6 ng/ml in LW×L pigs. Thus, the preovulatory follicular growth and the ovulatory efficiency seem not to be the main limiting factors for reproductive efficiency in Iberian swine. The gonadotropins induced a significant increase, when compared to untreated females (P<0.05), in the number of follicles larger than 4.9 mm growing throughout the follicular phase; however, estradiol values at estrus were lower (P<0.05) in both breeds (9.2±0.7 pg/ml in Iberian vs. 8.6±0.8 pg/ml in LW×L), when compared with the nontreated animals, which suggests defective follicular function after gonadotropin stimulation. There were also no differences between genotypes in ovulation rate (15.2±1.3 vs. 12.7±1.8) and progesterone secretion (21.2±0.8 ng/ml in Iberian and 20.9±0.7 ng/ml in LW×L sows) in the treated animals. In conclusion, the current findings indicate that preovulatory follicular growth and ovulatory efficiency are not main limiting factors for prolificacy in a pig model of leptin resistance and obesity.

Hard spheres: crystallization and glass formation

Motivated by old experiments on colloidal suspensions, we report molecular dynamics simulations of assemblies of hard spheres, addressing crystallization and glass formation. The simulations cover wide ranges of polydispersity s (standard deviation of the particle size distribution divided by its mean) and particle concentration. No crystallization is observed for s>0.07. For 0.02<s<0.07, we find that increasing the polydispersity at a given concentration slows down crystal nucleation. The main effect here is that polydispersity reduces the supersaturation since it tends to stabilize the fluid but to destabilize the crystal. At a given polydispersity (<0.07), we find three regimes of nucleation: standard nucleation and growth at concentrations in and slightly above the coexistence region; 'spinodal nucleation', where the free-energy barrier to nucleation appears to be negligible, at intermediate concentrations; and, at the highest concentrations, a new mechanism, still to be fully understood, which only requires small rearrangement of the particle positions. The cross-over between the second and third regimes occurs at a concentration, approximately 58 per cent by volume, where the colloid experiments show a marked change in the nature of the crystals formed and the particle dynamics indicate an 'ideal' glass transition.