Genitourinary symptoms and sexual function in women with primary ovarian insufficiency

OBJECTIVE

There are limited studies on urogenital symptoms in women who experience menopause before the age of 40 years due to primary ovarian insufficiency (POI) or bilateral oophorectomy (surgical POI). This study aimed to compare the urogenital symptoms, including sexuality, of women with POI to those without the condition.

METHODS

This cross-sectional study conducted was in seven Latin American countries, in which postmenopausal women (with POI and non-POI) were surveyed with a general questionnaire, the Menopause Rating Scale (MRS) and the six-item Female Sexual Function Index (FSFI-6). The association of premature menopause with more urogenital symptoms and lower sexual function was evaluated with logistic regression analysis.

RESULTS

Women with POI experience more urogenital symptoms (MRS urogenital score: 3.54 ± 3.16 vs. 3.15 ± 2.89, p < 0.05) and have lower sexual function (total FSFI-6 score: 13.71 ± 7.55 vs. 14.77 ± 7.57 p < 0.05) than women who experience menopause at a normal age range. There were no significant differences in symptoms when comparing women based on the type of POI (idiopathic or surgical). After adjusting for covariates, our logistic regression model determined that POI is associated with more urogenital symptoms (odds ratio [OR]: 1.38, 95% confidence interval [CI] 1.06-1.80) and lower sexual function (OR: 1.67, 95% CI 1.25-2.25).

CONCLUSION

POI, whether idiopathic or secondary to bilateral oophorectomy, is associated with symptoms that affect vaginal and sexual health.

Prevalence of asymptomatic Leishmania infection and knowledge, perceptions, and practices in blood donors in mainland Portugal

BACKGROUND

Asymptomatic infection is the most common outcome of exposure to Leishmania parasites. In the Mediterranean region, where Leishmania infantum is endemic, studies on the prevalence of asymptomatic infection have often relied on serological testing in blood donors. In Spain, regional studies have shown seroprevalence in blood donors between 1 and 8%; in Portugal, values of 0 and 2% were suggested by two localized studies, in different populations. The purpose of this study was (i) to estimate the prevalence of asymptomatic Leishmania infection in blood donors in mainland Portugal, and (ii) to study the association between the detection of antibodies to Leishmania and sociodemographic factors, and also the knowledge, perceptions and practices (KPP) of the blood donors regarding leishmaniasis.

METHODS

A cross-sectional study targeted the population of people who donated blood in mainland Portugal. Participants, distributed proportionally by municipality and aged between 18 and 65 years, were selected randomly in 347 blood collection points between February and June 2022, and completed a sociodemographic and a KPP questionnaire. Detection of anti-Leishmania antibodies in serum was performed using an ELISA commercial kit. Individual KPP scores were calculated by adding grades defined for each question.

RESULTS

Globally, 201/3763 samples were positive. The estimated national true seroprevalence was 4.8% (95% CI 4.1-5.5%). The proportion of positive results was significantly different between NUTS (Nomenclature of Territorial Units for Statistics) regions. Models suggested that seropositivity was significantly higher in male sex, people older than 25 years, or residing in the Centro NUTS2 region, but not in dog owners nor people with lower KPP scores. Overall, 72.3% of participants had previously heard of leishmaniasis and, in multivariate analysis, a higher Knowledge score was associated with age 25-40 years, female sex, ownership of dogs, and higher education.

CONCLUSIONS

Global estimated true seroprevalence (4.8%) was similar to previous regional studies in blood donors in neighboring Spain. Higher seroprevalence values in the NUTS2 Centro region were consistent with incidence data from humans and seroprevalence studies in dogs. On the other hand, the low values in the Alentejo and the high values in the northern subregions may be the result of geographical shifts in parasite circulation due to climate change and should prompt localized and integrated, vector, canine, and human research, following a One Health approach.

On the physicochemical properties, setting chemical reaction, and in vitro bioactivity of aragonite–chitosan composite cement as a bone substitute

A chitosan gel additive modulates the initial vaterite dissolution–recrystallisation in injectable aragonite-based composite cement and promotes its in vitro bioactivity.

Impact of acetaminophen on the efficacy of immunotherapy in cancer patients

BACKGROUND

Acetaminophen (APAP) use has been associated with blunted vaccine immune responses. This study aimed to assess APAP impact on immunotherapy efficacy in patients with cancer.

PATIENTS AND METHODS

Exposure to APAP was assessed by plasma analysis and was correlated with clinical outcome in three independent cohorts of patients with advanced cancer who were treated with immune checkpoint blockers (ICB). APAP immunomodulatory effects were evaluated on a pre-clinical tumor model and on human peripheral blood mononuclear cells (PBMCs) from healthy donors.

RESULTS

Detectable plasma APAP levels at treatment onset was associated with a significantly worse clinical outcome in ICB-treated cancer patients, independently of other prognostic factors. APAP significantly reduced ICB efficacy in the pre-clinical MC38 model, as well as the production of PD1 blockade-related interferon-γ secretion by human PBMCs. Moreover, reduction of ICB efficacy in vivo was associated with significantly increased tumor infiltration by regulatory T cells (Tregs). Administration of APAP over 24 h induced a significant expansion of peripheral Tregs in healthy individuals. In addition, interleukin-10, a crucial mediator of Treg-induced immune suppression, was significantly upregulated upon treatment with ICB in cancer patients taking APAP.

CONCLUSION

This study provides strong pre-clinical and clinical evidence of the role of APAP as a potential suppressor of antitumor immunity. Hence, APAP should be used with caution in patients treated with ICB.

Pembrolizumab in soft-tissue sarcomas with tertiary lymphoid structures: a phase 2 PEMBROSARC trial cohort

Immune checkpoint inhibitors (ICIs) show limited clinical activity in patients with advanced soft-tissue sarcomas (STSs). Retrospective analysis suggests that intratumoral tertiary lymphoid structures (TLSs) are associated with improved outcome in these patients. PEMBROSARC is a multicohort phase 2 study of pembrolizumab combined with low-dose cyclophosphamide in patients with advanced STS (NCT02406781). The primary endpoint was the 6-month non-progression rate (NPR). Secondary endpoints included objective response rate (ORR), progression-free survival (PFS), overall survival (OS) and safety. The 6-month NPR and ORRs for cohorts in this trial enrolling all comers were previously reported; here, we report the results of a cohort enrolling patients selected based on the presence of TLSs (n = 30). The 6-month NPR was 40% (95% confidence interval (CI), 22.7-59.4), so the primary endpoint was met. The ORR was 30% (95% CI, 14.7-49.4). In comparison, the 6-month NPR and ORR were 4.9% (95% CI, 0.6-16.5) and 2.4% (95% CI, 0.1-12.9), respectively, in the all-comer cohorts. The most frequent toxicities were grade 1 or 2 fatigue, nausea, dysthyroidism, diarrhea and anemia. Exploratory analyses revealed that the abundance of intratumoral plasma cells (PCs) was significantly associated with improved outcome. These results suggest that TLS presence in advanced STS is a potential predictive biomarker to improve patients' selection for pembrolizumab treatment.

CHK1 inhibition in soft-tissue sarcomas: biological and clinical implications

Background

Inhibition of ChK1 appears as a promising strategy for selectively potentiate the efficacy of chemotherapeutic agents in G1 checkpoint-defective tumor cells such as those that lack functional p53 protein. The p53 pathway is commonly dysregulated in soft-tissue sarcomas (STS) through mutations affecting TP53 or MDM2 amplification. GDC-0575 is a selective ATP-competitive inhibitor of CHK1.

Methods

We have performed a systematic screening of a panel of 10 STS cell lines by combining the treatment of GDC-0575 with chemotherapy. Cell proliferation, cell death and cell cycle analysis were evaluated with high throughput assay. In vivo experiments were carried out by using TP53-mutated and TP53 wild-type patient-derived xenograft models of STS. Clinical activity of GDC-0575 combined with chemotherapy in patients with TP53-mutated and TP53 wild-type STS was also assessed.

Results

We found that GDC-0575 abrogated DNA damage-induced S and G2-M checkpoints, exacerbated DNA double-strand breaks and induced apoptosis in STS cells. Moreover, we observed a synergistic or additive effect of GDC-0575 together with gemcitabine in vitro and in vivo in TP53-proficient but not TP53-deficient sarcoma models. In a phase I study of GDC-0575 in combination with gemcitabine, two patients with metastatic TP53-mutated STS had an exceptional, long-lasting response despite administration of a very low dose of gemcitabine whereas one patient with wild-type TP53 STS had no clinical benefit. Genetic profiling of samples from a patient displaying secondary resistance after 1 year showed loss of one preexisting loss-of-function mutation in the helical domain of DNA2.

Conclusion

We provide the first preclinical and clinical evidence that potentiation of chemotherapy activity with a CHK1 inhibitor is a promising strategy in TP53-deficient STS and deserves further investigation in the phase II setting.

Analyses of seven new whole genome sequences of cassava brown streak viruses in Mozambique reveals two distinct clades: evidence for new species

Cassava brown streak disease (CBSD) caused by Cassava brown streak virus (CBSV) and Uganda cassava brown streak virus (UCBSV) is a major constraint to cassava production in Mozambique. Full genome sequences of CBSD-associated virus isolates contribute to the understanding of genetic diversity and the development of new diagnostic primers that can be used for early detection of the viruses for sustainable disease management. This study determined seven new whole CBSV genomes from total RNA isolated from cassava leaves with CBSD symptoms collected from Nampula and Zambezia in Mozambique. Phylogenetic analyses of the new genomes with published CBSV and UCBSV sequences in GenBank grouped the CBSV isolates from Mozambique into two distinct clades together with CBSV isolates from Tanzania. Clade 1 and 2 isolates shared low nucleotide (79.1-80.4%) and amino acid (86.5-88.2%) sequence identity. Further, comparisons within the seven new CBSV isolates, and between them and the single published complete CBSV sequence (CBSV_MO_83_FN434436) from Mozambique, revealed nucleotide sequence identities of 79.3-100% and 79.3-98%, respectively, and amino acid identities of 86.7-100% and 86.7-98.8%. In addition, using RDP4, a recombination analysis comprising all CBSV and UCBSV genome sequences from GenBank detect 11 recombination events. Using several comprehensive evolutionary models and statistical programs, it was confirmed that CBSV and UCBSV are distinct virus species, with an additional probable new species (clade 2).

Dietary n-3 long chain PUFA supplementation promotes a pro-resolving oxylipin profile in the brain

The brain is highly enriched in long chain polyunsaturated fatty acids (LC-PUFAs) that display immunomodulatory properties in the brain. At the periphery, the modulation of inflammation by LC-PUFAs occurs through lipid mediators called oxylipins which have anti-inflammatory and pro-resolving activities when derived from n-3 LC-PUFAs and pro-inflammatory activities when derived from n-6 LC-PUFAs. However, whether a diet rich in LC-PUFAs modulates oxylipins and neuroinflammation in the brain has been poorly investigated. In this study, the effect of a dietary n-3 LC-PUFA supplementation on oxylipin profile and neuroinflammation in the brain was analyzed. Mice were given diets deficient or supplemented in n-3 LC-PUFAs for a 2-month period starting at post-natal day 21, followed by a peripheral administration of lipopolysaccharide (LPS) at adulthood. We first showed that dietary n-3 LC-PUFA supplementation induced n-3 LC-PUFA enrichment in the hippocampus and subsequently an increase in n-3 PUFA-derived oxylipins and a decrease in n-6 PUFA-derived oxylipins. In response to LPS, n-3 LC-PUFA deficient mice presented a pro-inflammatory oxylipin profile whereas n-3 LC-PUFA supplemented mice displayed an anti-inflammatory oxylipin profile in the hippocampus. Accordingly, the expression of cyclooxygenase-2 and 5-lipoxygenase, the enzymes implicated in pro- and anti-inflammatory oxylipin synthesis, was induced by LPS in both diets. In addition, LPS-induced pro-inflammatory cytokine increase was reduced by dietary n-3 LC-PUFA supplementation. These results indicate that brain n-3 LC-PUFAs increase by dietary means and promote the synthesis of anti-inflammatory derived bioactive oxylipins. As neuroinflammation plays a key role in all brain injuries and many neurodegenerative disorders, the present data suggest that dietary habits may be an important regulator of brain cytokine production in these contexts.

Safety of aerosol therapy in children during noninvasive ventilation with helmet and total face mask

PURPOSE

To evaluate the consequences of using nebulized drugs in patients subjected to noninvasive ventilation (NIV) with total face mask (TFM) and helmet.

DESIGN

A descriptive analytical study of a prospective patient cohort was carried out.

AMBIT

Pediatric intensive care unit (PICU) of a tertiary hospital.

PATIENTS

Consecutive sampling was used to include all patients admitted to the PICU and requiring NIV with helmet or TFM over a period of 29 months. No patients were excluded.

INTERVENTIONS

Nebulized treatment was added according to medical criteria.

VARIABLES OF INTEREST

Independent variables were age, sex, diagnosis, disease severity, ventilation parameters and nebulized drugs (if administered). Secondary outcomes were duration and failure of NIV, and length of PICU stay.

RESULTS

The most frequent diagnoses were bronchiolitis (60.5%) and asthma (23%). Patients received NIV for a median of 43h. Nebulized drugs were administered in 40% of the cases during NIV, and no adverse effects were registered. Using Bayesian statistics, the calculated probability of suffering an adverse effect was 1.3% with helmet and 0.5% with TFM (high density 95% probability intervals). Patients with helmet and nebulized therapy were in more serious condition than those who did not receive nebulization; nevertheless, no differences were observed regarding the need to change to bilevel modality. With TFM, PICU stay was shorter for the same degree of severity (p=0.033), and the NIV failure rate was higher in patients who did not receive inhaled drugs (p=0.024).

CONCLUSIONS

The probability of suffering an adverse effect related to nebulization is extremely low when using a helmet or TFM. Inhaled therapy with TFM may shorten PICU stay in some patients.

Optical Coherence Tomography in Children With Microtropia

PURPOSE

To assess whether optical coherence tomography (OCT) could be useful for detecting and documenting fixation in patients with microtropia.

METHODS

Retinal fixation observation was performed using spectral-domain OCT on amblyopic children with microtropia. The position between the retinal fixation point and the anatomical fovea was measured, in microns, using the system software tools. Only patients with a high level of cooperation, OCT scan quality signal of 7 or better, and visual acuity of 0.70 logarithm of the minimum angle of resolution (logMAR) or worse in the amblyopic eye were included.

RESULTS

A total of 25 patients were included: 15 with microtropia (study group) and 10 without tropia and with foveal fixation and stereopsis (control group). In the study group, microtropia was previously diagnosed in 67% of cases through the cover test, and was predominantly in the left eye (73%). The average visual acuity of the sound eye was 0.03 decimal and 0.18 logMAR in the amblyopic eye. The microtropia was 3.73 ± 3.34 prism diopters and eccentric fixation (387 ± 199 µm) with OCT was observed in all cases except one. Eccentricity was predominantly in the superonasal quadrant (57%). Both eyes in the control group and the contralateral eyes of the study group showed foveal fixation.

CONCLUSIONS

OCT can play an important role in the diagnosis and measurement of eccentric fixation in eyes with microtropia, providing high sensitivity. [J Pediatr Ophthalmol Strabismus. 2018;55(3):171-177.].

Atrial fibrillation is associated with hypermethylation in human left atrium, and treatment with decitabine reduces atrial tachyarrhythmias in spontaneously hypertensive rats

Atrial fibrillation (AF) is the most common cardiac arrhythmia. As the molecular mechanisms underlying the pathology are largely unknown, this cardiac arrhythmia remains difficult to treat. To identify specific molecular actors involved in AF, we have performed a transcriptomic analysis on left atrium (LA) from patients with valvular heart disease with or without AF. We showed that 1627 genes had altered basal expression level in LA tissue of AF patients compared with the control group. The significantly enriched gene ontology biological process "anatomical structure morphogenesis" contained the highest number of genes in line with changes in structure that occur when the human heart remodels following AF development (ie, LA dilatation and interstitial fibrosis). We then focused the study on Pitx2 (paired-like homeodomain 2), being the most altered transcription factor in LA from AF patients and from which compelling evidence have indicated that its reduced expression can be considered as a marker for the disease. In addition, its expression was inversely correlated with LA size. We demonstrated that AF is associated with Pitx2 promoter hypermethylation both in humans and arrhythmic aging spontaneously hypertensive rats. Chronic administration of a DNA methylation inhibitor (ie, 5-Aza-2'-deoxycitidine) improved ECG arrhythmic profiles and superoxide dismutase activities and reduced fibrosis in the left ventricle of spontaneously hypertensive rats. Taken together, these data support the notion that AF is associated with epigenetic changes in LA and provide a proof-of-concept that hypomethylating agents have to be considered in the treatment of atrial arrhythmias.

Effect of self-esteem on social interactions during the Ultimatum Game

Self-esteem is an attitude formed by self-evaluation based on positive and negative aspects of oneself. Low self-esteem is a risk factor for psychiatric disorders and is especially associated with social difficulties. Recently, behavioral economics has allowed the quantitative study of social interactions. We investigated the association between self-esteem and interpersonal problems and whether self-esteem modulates behavior and emotions during an economic task, the Ultimatum Game (UG). In this task participants accept or reject fair/unfair monetary offers from others. Low (LSE, n=40) and high (HSE, n=45) self-esteem participants were assessed in their interpersonal problems and psychiatric symptoms using self-reported questionnaires, and were compared on their decision making and emotional response during the UG. LSE was associated with depression and anxiety symptoms. In addition, LSE was associated with interpersonal problems, especially in the domains of socially inhibited, nonassertive, overly accommodating, self-sacrificing and cold/distant. During the UG, LSE women reported more anger towards unfair offers than HSE women. Our findings suggest that low self-esteem individuals experience high distress by interpersonal problems in several domains. Importantly, low self-esteem in women seems to be associated with an accentuated emotional response to unfair social exchanges. These results may contribute to treat social difficulties in this population.

Enriched dairy fat matrix diet prevents early life lipopolysaccharide-induced spatial memory impairment at adulthood

Polyunsaturated fatty acids (PUFAs) are essential fatty acids, which are critical for brain development and later life cognitive functions. The main brain PUFAs are docosahexaenoic acid (DHA) for the n-3 family and arachidonic acid (ARA) for the n-6 family, which are provided to the post-natal brain by breast milk or infant formula. Recently, the use of dairy lipids (DL) in replacement of vegetable lipids (VL) was revealed to potently promote the accretion of DHA in the developing brain. Brain DHA, in addition to be a key component of brain development, display potent anti-inflammatory activities, which protect the brain from adverse inflammatory events. In this work, we evaluated the protective effect of partial replacement of VL by DL, supplemented or not with DHA and ARA, on post-natal inflammation and its consequence on memory. Mice were fed with diets poor in vegetal n-3 PUFA (Def VL), balanced in vegetal n-3/n-6 PUFA (Bal VL), balanced in dairy lipids (Bal DL) or enriched in DHA and ARA (Supp VL; Supp DL) from the first day of gestation until adulthood. At post-natal day 14 (PND14), pups received a single administration of the endotoxin lipopolysaccharide (LPS) and brain cytokine expression, microglia phenotype and neurogenesis were measured. In a second set of experiments, memory and neurogenesis were measured at adulthood. Overall, our data showed that lipid quality of the diet modulates early life LPS effect on microglia phenotype, brain cytokine expression and neurogenesis at PND14 and memory at adulthood. In particular, Bal DL diet protects from the adverse effect of early life LPS exposure on PND14 neurogenesis and adult spatial memory.

Resolvin D1 and E1 promote resolution of inflammation in microglial cells in vitro

Sustained inflammation in the brain together with microglia activation can lead to neuronal damage. Hence limiting brain inflammation and activation of microglia is a real therapeutic strategy for inflammatory disease. Resolvin D1 (RvD1) and resolvin E1 (RvE1) derived from n-3 long chain polyunsaturated fatty acids are promising therapeutic compounds since they actively turn off the systemic inflammatory response. We thus evaluated the anti-inflammatory activities of RvD1 and RvE1 in microglia cells in vitro. BV2 cells were pre-incubated with RvD1 or RvE1 before lipopolysaccharide (LPS) treatment. RvD1 and RvE1 both decreased LPS-induced proinflammatory cytokines (TNF-α, IL-6 and IL-1β) gene expression, suggesting their proresolutive activity in microglia. However, the mechanisms involved are distinct as RvE1 regulates NFκB signaling pathway and RvD1 regulates miRNAs expression. Overall, our findings support that pro-resolving lipids are involved in the resolution of brain inflammation and can be considered as promising therapeutic agents for brain inflammation.

Management by missions in the healthcare sector

This article discusses the importance of the mission statement in the healthcare sector. It's also argued that only formal declaration of the mission it's insufficient to the appropriate professional coordination of doctors, nurses and managers. It's proposed a systematic approach to facilitate the introduction of the mission within the systems of the organization, what is called "Management by missions." It promotes horizontal and vertical integration between doctors, nurses and managers. Criteria that ensure this integration are specified.

Dairy fat blend improves brain DHA and neuroplasticity and regulates corticosterone in mice

Mimicking the breast milk lipid composition appears to be necessary for infant formula to cover the brain's needs in n-3 PUFA. In this study, we evaluated the impact of partial replacement of vegetable oil (VL) in infant formula by dairy fat (DL) on docosahexaenoic acid (DHA) brain level, neuroplasticity and corticosterone in mice. Mice were fed with balanced VL or balanced DL diets enriched or not in DHA and arachidonic acid (ARA) from the first day of gestation. Brain DHA level, microglia number, neurogenesis, corticosterone and glucocorticoid receptor expression were measured in the offsprings. DL diet increased DHA and neuroplasticity in the brain of mice at postnatal day (PND) 14 and at adulthood compared to VL. At PND14, ARA and DHA supplementation increased DHA in VL but not in DL mice brain. Importantly, DHA and ARA supplementation further improved neurogenesis and decreased corticosterone level in DL mice at adulthood. In conclusion, dairy lipids improve brain DHA level and neuroplasticity.

Reinforced silica monoliths functionalised with metal hexacyanoferrates for cesium decontamination: a combination of a one-pot procedure and skeleton calcination

Procedure describes the synthesis of silica monoliths functionalised with metal hexacyanoferrate (MHCF) using a high internal phase emulsion template. The materials exhibit excellent Cs ion sorption properties.

[Unexplicated neuropsychiatric disorders: Do not ignore dysimmune encephalitis. A case report of a dysimmune encephalitis with anti-leucine rich glioma inactivated 1 (LGI-1) antibodies]

INTRODUCTION

Anti-leucine rich glioma inactivated 1 encephalitis is a common and a treatable etiology of autoimmune encephalitis. Its diagnosis is a challenge because the initial diagnostic work-up is often normal.

CASE REPORT

A 48-year-old man experienced cognitive and behavioral troubles, facio-brachial dystonic seizures and a syndrome of inappropriate antidiuretic hormone secretion. First line tests excluded infectious, neoplastic, systemic inflammatory, endrocrine or toxic etiologies. Cerebral (18)Fluoro-desoxy-glucose (FDG) position emission tomography and research of specific antibodies in cerebro-spinal fluid and serum led to diagnose an anti-leucine rich glioma inactivated 1 encephalitis. Intravenous immunoglobulins and corticosteroids were partially effective. Cyclophosphamid permitted a good recovery.

CONCLUSION

In the presence of acute neuropsychiatric disorders with a negative etiologic research, physician should think about dysimmune encephalitis. Facio-brachial dystonic seizures and syndrome of inappropriate antidiuretic hormone secretion are highly evocative of anti-leucine rich glioma inactivated 1 encephalitis. The diagnosis needs specific diagnostic tests (cerebral (18)FDG position emission tomography and antibodies research in cerebro-spinal fluid and in serum), after the exclusion of alternative diagnoses. Extensive and repeated diagnostic work-up for neoplasia is required. Immunosupressive therapies are effective in most cases.

Adsorption on apatitic calcium phosphates for drug delivery: interaction with bisphosphonate molecules

Bisphosphonates (BPs) are well established as an important class of drugs for the treatment and prevention of several bone disorders including osteoporosis. This work investigated the interaction of two bisphosphonates, risedronate and tiludronate, with several apatitic supports, a well-crystallised hydroxyapatite (HA) and nanocrystalline apatites with varying maturation times, chemical composition and surface characteristics. The purpose was to fully understand the adsorption mechanism and desorption process, by the evaluation of the effect of several physicochemical parameters (temperature, pH and concentration of calcium and phosphate ions). Whatever the nature of the BP and the structure and composition of the apatite, the adsorption of such anti-resorptive agents can be well described as an ion exchange-reaction between phosphates species on the apatitic surface and BP molecules in solution. However, the parameters of adsorption can vary depending on the physicochemical conditions of the adsorption reaction. In addition, the structure and composition of the apatitic surface also influence the adsorption properties. Finally, BPs molecules are slowly released from apatitic supports, because most of the adsorbed molecules are irreversibly bound and not spontaneously released by dilution or simple washing. Moreover, similar to their adsorption, the release of bisphosphonates is strongly affected not only by the chemical properties of the molecule, but also by the chemical and structural characteristics of the apatitic substrates. The understanding of the adsorption and release processes provides fundamental tools for the development of drug delivery systems using apatite materials.

Mapping radon-prone areas using γ-radiation dose rate and geological information

Identifying radon-prone areas is key to policies on the control of this environmental carcinogen. In the current paper, we present the methodology followed to delineate radon-prone areas in Spain. It combines information from indoor radon measurements with γ-radiation and geological maps. The advantage of the proposed approach is that it lessens the requirement for a high density of measurements by making use of commonly available information. It can be applied for an initial definition of radon-prone areas in countries committed to introducing a national radon policy or to improving existing radon maps in low population regions.

[Favourable outcome after treatment with rituximab in a case of seronegative non-paraneoplastic Lambert-Eaton myasthenic syndrome]

INTRODUCTION

Lambert-Eaton myasthenic syndrome is a rare and autoimmune presynaptic disorder of the neuromuscular junction, due in 85% of cases to autoantibodies directed against voltage-gated calcium channels. It is a paraneoplastic disorder in 50 to 60% of cases. Diagnosis involves a proximal muscle weakness and areflexia, associated with a significant increment after post-exercise stimulation in electrophysiological study. Symptomatic treatment is based on 3,4-diaminopyridine. No etiological treatment has proven its efficacy in both paraneoplastic and non-paraneoplastic Lambert-Eaton myasthenic syndrome.

CASE REPORT

We report a 41-year-old man who presented with a seronegative non-paraneoplastic Lambert-Eaton myasthenic syndrome in whom conventional immunosuppressive treatments (corticosteroids, azathioprine) failed, and who eventually improved after treatment with rituximab.

CONCLUSION

Rituximab was an effective and well-tolerated treatment in this case of seronegative non-paraneoplastic Lambert-Eaton myasthenic syndrome. Its indication should be discussed when conventional immunosuppressive therapy fails in both seropositive and seronegative patients.

A comparative physico-chemical study of chlorapatite and hydroxyapatite: from powders to plasma sprayed thin coatings

Due to their bioactivity and osteoconductivity, hydroxyapatite (HA) plasma sprayed coatings have been widely developed for orthopedic uses. However, the thermodynamic instability of HA leads frequently to a mixture of phases which limit the functional durability of the coating. This study investigates the plasma spraying of chlorapatite (ClA) powder, known to melt without decomposition, onto pure titanium substrates using a low energy plasma spray system (LEPS). Pure ClA powder was prepared by a solid gas reaction at 950 °C and thermogravimetric analysis showed the good thermal stability of ClA powder in the range 30-1400 °C compared to that of the HA powder. Characterization of ClA coating showed that ClA had a very high crystalline ratio and no other crystalline phase was detected in the coating. HA and ClA coatings composition, microstructure and in vitro bioactivity potential were studied, compared and discussed. In vitro SBF test on HA and ClA coatings revealed the formation of a poorly crystalline apatite on the coating surface suggesting that we could expect a good osteoconductivity especially for the ClA coating prepared by the LEPS system.

Interaction between a bisphosphonate, tiludronate and nanocrystalline apatite: in vitro viability and proliferation of HOP and HBMSC cells

Nanocrystalline apatites (NCA) are the inorganic components of mineralized tissues and they have been recently proposed as biomaterials for drug delivery systems. Bisphosphonates (BPs) are currently the reference drugs used to treat diseases involving bone disorders such as osteoporosis. Nevertheless, the interaction phenomena between BP molecules and apatite nanocrystals of bone are not well understood. Therefore, the adsorption characteristics have been examined and cellular activity of tiludronate molecules on NCA as models of bone mineral has been investigated. Adsorption experiments of tiludronate onto NCA were carried out and revealed a Langmuir-type adsorption isotherm. The uptake of tiludronate molecules is associated with a release of phosphate ions, indicating that the main reaction is an ion exchange process involving surface anions. The results evidence the strong affinity of BP molecules for the apatitic surface. The interactions of NCA-tiludronate associations with human osteoprogenitor cells and human bone marrow stromal cells do not reveal any cytotoxicity and evidence the activity of adsorbed tiludronate molecules. Moreover, an evolution of the physico-chemical characteristics of the apatitic substrate during biological study was observed, highlighting the existence of dynamic interactions. This work contributes to clarifying the reaction mechanisms between BPs and biomimetic apatites.

Co-grinding significance for calcium carbonate-calcium phosphate mixed cement. Part I: effect of particle size and mixing on solid phase reactivity

In part I of this study we aim to evaluate and control the characteristics of the powders constituting the solid phase of a vaterite CaCO(3)-dicalcium phosphate dihydrate cement using a co-grinding process and to determine their impact on cement setting ability. An original methodology involving complementary analytical techniques was implemented to thoroughly investigate the grinding mechanism of separated or mixed reactive powders and the effects on solid phase reactivity. We showed that the association of both reactive powders during co-grinding improves the efficiency of this process in terms of the particle size decrease, thus making co-grinding adaptable to industrial development of the cement. For the first time the usefulness of horizontal attenuated total reflection Fourier transform infrared spectroscopy to follow the chemical setting reaction at 37°C in real time has been demonstrated. We point out the antagonist effects that co-grinding can have on cement setting: the setting time is halved; however, progress of the chemical reaction involving dissolution-reprecipitation is delayed by 30 min, probably due to the increased contact area between the reactive powders, limiting their hydration. More generally, we can take advantage of the co-grinding process to control powder mixing, size and reactivity and this original analytical methodology to better understand its effect on the phenomena involved during powder processing and cement setting, which is decisive for the development of multi-component cements.

Helmet-delivered heliox-CPAP in severe upper airway obstruction caused by PHACES syndrome

We present the case of a 4-month-old girl with PHACES syndrome and severe upper respiratory airway obstruction secondary to multiple subglottic and tracheal hemangiomas effectively treated with heliox-CPAP delivered by helmet (HH-CPAP).

Nanocrystalline Apatites for Bone Reconstruction

Poorly crystalline apatites (PCA) are characterized by a non-stoichiometric composition, a high specific surface area and the existence of labile, non-apatitic environments detected by spectroscopic techniques. These environments have been shown to belong mainly to an hydrated layer at the surface of the crystals and determine their surface and bulk reactivity. PCA can be easily synthesized in aqueous media and the amount of labile, non-apatitic environments can be modulated by using apatites at different maturation stage. PCA can adsorb many active proteins or drugs, Growth factors (FGF-2, for example), were strongly bound and remained mostly attached to the surface. Several mineral ions which have been shown to have a biological activity such as strontium, can also be trapped at the surface or into the lattice of poorly crystalline apatites. Due to their reactivity, PCA cannot be shaped easily into materials, however, they have the ability to agglomerate irreversibly into solid body at low temperature. These low temperature ceramics show a variable amount of pores (30 to 60 %) and pore size (5 to 25 nm) in which organic components can be trapped and are released only by the dissolution of the ceramic.

Amorphous calcium phosphates: synthesis, properties and uses in biomaterials

This review paper on amorphous calcium phosphates (ACPs) provides an update on several aspects of these compounds which have led to many studies and some controversy since the 1970s, particularly because of the lack of irrefutable proof of the occurrence of an ACP phase in mineralised tissues of vertebrates. The various synthesis routes of ACPs with different compositions are reported and the techniques used to characterise this phase are reviewed. We focus on the various physico-chemical properties of ACPs, especially the reactivity in aqueous media, which have been exploited to prepare bioactive bone substitutes, particularly in the form of coatings and cements for orthopaedic applications and composites for dental applications.

Helmet-delivered continuous positive airway pressure with heliox in respiratory syncytial virus bronchiolitis

AIM

The objective of this study was to check the feasibility and efficacy of helmet-delivered heliox-continuous positive airway pressure (CPAP) in infants with bronchiolitis.

METHODS

Children <3 months of age diagnosed with respiratory syncytial virus bronchiolitis and recurrent apnoeas or a venous PCO(2) >55 mmHg or a transcutaneous oxygen saturation <92% in room air were eligible for inclusion in the study. CPAP was delivered by a noninvasive ventilator connected to a heliox port. The interface was a helmet.

RESULTS

Eight consecutive infants fulfilled the inclusion criteria. Apnoeas were present in six children before respiratory support was started; they disappeared in five of them. Two infants had to be changed to pressure support noninvasive ventilation, and one of them required intubation. No side effects were recorded.

CONCLUSION

We propose a relatively new device to deliver heliox-CPAP in small infants with bronchiolitis. Although this is just a descriptive study with a short sample, this system seems to be feasible and effective.

Pulmonary valve motion in valvular pulmonary stenosis in childhood

Echocardiography tracings of the pulmonary valve was recorded in 16 patients with pulmonic stenosis (PS) ranging in ages from 6 to 14 years (average 10 years). 11 patients had an isolated PS and 5 had a PS associated with atrial septal defect. In 2 patients with mild PS (gradient 15 mm Hg) the depth of the "a" wave was normal: 3 and 4 mm. In 14 patients with moderate or severe PS (gradient 40 mm to 200 mm Hg), the maximal depth of the "a" wave was less than 6 mm in 2 patients, and more than 6 mm in 12 patients (range 7 to 15 mm, average 10 mm). The motion of both anterior and posterior pulmonary valve leaflets was well recorded in 3 patients with severe PS. The "a" wave showed a posterior motion of the posterior leaflets and an anterior motion of the anterior leaflet. This motion is due to the premature pulmonary valve opening.