Expression of Toll-like receptors 2 and 4 and its association with matrix metalloproteinases in symptomatic and asymptomatic apical periodontitis.

To determine Toll-like receptors (TLR)2 and TLR4 expression levels and associate them with matrix metalloproteinases (MMPs) in asymptomatic apical periodontitis (AAP), symptomatic apical periodontitis (SAP), and healthy controls. Apical tissue/lesion samples were obtained from chronic AAP (n = 35) and SAP (n = 29), and healthy periodontal ligament (HPL, n = 10) with indication of tooth extraction, respectively. mRNA expression levels of TLR2, TLR4, MMP-1, MMP-2, MMP-8, and MMP-13 were determined by real-time reverse-transcription polymerase chain reaction. The data were analyzed with Kruskal-Wallis and Dunn's pot hoc test (p < 0.05). The correlation coefficient was obtained using the Spearman correlation (p < 0.05). TLR2, MMP-1, MMP-2, and MMP-13 mRNA levels were the highest in SAP followed by AAP and controls (p < 0.05). TLR4 and MMP-8 were over expressed in AAP and SAP compared to HPL (p < 0.05). TLR2 positively correlated with TLR4, MMP-1, MMP-8, and MMP-13 in SAP (p < 0.05). TLR2 and TLR4 are overexpressed in apical lesions versus healthy periodontal ligament and correlate with collagenolytic MMPs. Particularly, TLR2 is overexpressed in SAP in association with MMP-1, MMP-8, and MMP-13. Our results suggest that the activation of TLR2 along with MMP overexpression might contribute to SAP clinical presentation and progression. TLRs, MMPs, and their interaction can explain the clinical presentations and evolution of apical periodontitis and might represent key targets for new diagnostic and treatment approaches.

Self-Regeneration of Chirality with l-Cysteine through 1,3-Dipolar Cycloadditions between Diazoalkanes and Enantiomerically Pure Thiazolines: Experimental and Computational Studies.

Enantiopure 2-thia-4-azabicyclo[3.1.0]hexanes, which can be considered constrained cysteines, have been obtained from l-cysteine by application of the "self-regeneration of chirality" concept. The key intermediates are homochiral thiazolines that can be prepared in multigram scale and react smoothly with a series of diazoalkanes providing Δ1-pyrazolines except for phenyldiazomethane that yield the isomeric Δ2-pyrazolines. Nitrogen extrusion in Δ1-pyrazolines and further reduction of the sulfinyl group yielded the target compounds in good overall yield. Computational studies of the cycloaddition reaction were used for determining the polarity of the process and explaining the observed stereoselectivity. Additional topological studies were employed for determining the influence of noncovalent interactions in the stereochemical course of the reaction, which showed to be a highly asynchronous concerted process.

Evidence Linking Brain Activity Modulation to Age and to Deductive Training.

Electrical brain activity modulation in terms of changes in its intensity and spatial distribution is a function of age and task demand. However, the dynamics of brain modulation is unknown when it depends on external factors such as training. The aim of this research is to verify the effect of deductive reasoning training on the modulation in the brain activity of healthy younger and older adults (N = 47 (mean age of 21 ± 3.39) and N = 38 (mean age of 68.92 ± 5.72)). The analysis reveals the benefits of training, showing that it lowers cerebral activation while increasing the number of correct responses in the trained reasoning task (p < 0.001). The brain source generators were identified by time-averaging low-resolution brain electromagnetic tomography (sLORETA) current density images. In both groups, a bilateral overactivation associated with the task and not with age was identified. However, while the profile of bilateral activation in younger adults was symmetrical in anterior areas, in the older ones, the profile was located asymmetrically in anterior and posterior areas. Consequently, bilaterality may be a marker of how the brain adapts to maintain cognitive function in demanding tasks in both age groups. However, the differential bilateral locations across age groups indicate that the tendency to brain modulation is determined by age.

Propensity Score Analysis of the Role of Initial Antifungal Therapy in the Outcome of Candida glabrata Bloodstream Infections.

Candida glabrata isolates have reduced in vitro susceptibility to azoles, which raises concerns about the clinical effectiveness of fluconazole for treating bloodstream infection (BSI) by this Candida species. We aimed to evaluate whether the choice of initial antifungal treatment (fluconazole versus echinocandins or liposomal amphotericin B [L-AmB]-based regimens) has an impact on the outcome of C. glabrata BSI. We analyzed data from a prospective, multicenter, population-based surveillance program on candidemia conducted in 5 metropolitan areas of Spain (May 2010 to April 2011). Adult patients with an episode of C. glabrata BSI were included. The main outcomes were 14-day mortality and treatment failure (14-day mortality and/or persistent C. glabrata BSI for ≥48 h despite antifungal initiation). The impact of using fluconazole as initial antifungal treatment on the patients' prognosis was assessed by logistic regression analysis with the addition of a propensity score approach. A total of 94 patients with C. glabrata BSI were identified. Of these, 34 had received fluconazole and 35 had received an echinocandin/L-AmB-based regimen. Patients in the echinocandin/L-AmB group had poorer baseline clinical status than did those in the fluconazole group. Patients in the fluconazole group were more frequently (55.9% versus 28.6%) and much earlier (median time, 3 versus 7 days) switched to another antifungal regimen. Overall, 14-day mortality was 13% (9/69) and treatment failure 34.8% (24/69), with no significant differences between the groups. On multivariate analysis, after adjusting for baseline characteristics by propensity score, fluconazole use was not associated with an unfavorable evolution (adjusted odds ratio [OR] for 14-day mortality, 1.16, with 95% confidence interval [CI] of 0.22 to 6.17; adjusted OR for treatment failure, 0.83, with 95% CI of 0.27 to 2.61). In conclusion, initial fluconazole treatment was not associated with a poorer outcome than that obtained with echinocandins/L-AmB regimens in patients with C. glabrata BSI. (This study has been registered at ClinicalTrials.gov under registration no. NCT01236261.).

C-Reactive protein and insulin growth factor 1 serum levels during the menstrual cycle in adolescents with Type 1 diabetes.

AIMS: To evaluate C-reactive protein, insulin growth factor 1 and lipid levels during the follicular and luteal phases in adolescents with Type 1 diabetes. METHODS: Adolescents with Type 1 diabetes (N = 40) and healthy controls (C; N = 43) were studied during the follicular and luteal phases of their menstrual cycles. C-Reactive protein, insulin growth factor 1 and lipid levels were measured. RESULTS: Adolescents with Type 1 diabetes exhibited higher C-reactive protein levels than the C group during the follicular (P < 0.0001) and luteal phases (P < 0.01). The elevation of C-reactive protein levels was more pronounced in overweight adolescents with Type 1 diabetes than in adolescents in the C group. More adolescents with Type 1 diabetes were classified as having an elevated risk of cardiovascular disease (C-reactive protein > 3 mg/l) in the luteal phase than in the follicular phase (37.5% and 17.5%, respectively); half of the overweight adolescents with Type 1 diabetes in the luteal phase reached this level. BMI was the only significant factor affecting follicular and luteal phase C-reactive protein levels in adolescents with Type 1 diabetes. Lower insulin growth factor 1 levels were observed during both phases of the menstrual cycle in adolescents with Type 1 diabetes compared with controls. An elevation in insulin growth factor 1 levels in the luteal phase relative to the follicular phase was observed in controls, but not in adolescents with Type 1 diabetes. Luteal insulin growth factor 1 and C-reactive protein exhibited an inverse correlation (r = -0.4, P = 0.01). CONCLUSIONS: Adolescents with Type 1 diabetes have higher C-reactive protein levels and lower insulin growth factor 1 levels relative to controls, especially during the luteal phase. Type 1 diabetes diminishes the natural elevation in insulin growth factor 1 levels observed during the luteal phase in controls. Excess weight exacerbates the subclinical inflammatory state observed during both phases of the menstrual cycle in adolescents with Type 1 diabetes.

Oestrogen activity of the serum in adolescents with Type 1 diabetes.

AIMS: To assess serum oestrogen levels and oestrogenic activity in adolescents with Type 1 diabetes compared with a healthy control group. METHODS: We conducted a cross-sectional study that evaluated adolescents with Type 1 diabetes (n = 38) and healthy adolescents (control group; n = 32). Serum oestrogens, urinary oestrogen metabolites and serum oestrogenic activity were assessed. Oestrogenic activity was evaluated in an in vitro cell proliferation assay using a modified E-screen assay with MCF-7/BUS cells. RESULTS: Adolescents with Type 1 diabetes had lower oestrogenic activity levels in both phases of the menstrual cycle compared with the control group (follicular phase: 76 vs 94%; luteal phase: 97 vs 131%; P < 0.01), even after adjusting for BMI, oestradiol and oestrone levels. Postmenarcheal adolescents with Type 1 diabetes had lower oestradiol levels compared with control subjects in the follicular phase (63.3 pmol/l vs 89.4 pmol/l; P < 0.01) and higher oestrone levels compared with controls in the luteal phase (196 vs 151.9 pmol/l; P < 0.05). CONCLUSIONS: Adolescents with Type 1 diabetes had lower levels of serum oestrogenic activity, and these were lower than expected based on their serum oestradiol levels. We postulate that changes in the serum milieu of oestrogens in patients with Type 1 diabetes may explain their decreased oestrogenic activity and may play a role in their adverse metabolic profile.

Computational Mechanistic Study of Thionation of Carbonyl Compounds with Lawesson's Reagent.

The thionation reaction of carbonyl compounds with Lawesson's reagent (LR) has been studied using density functional theory methods and topological analyses. After dissociation of LR, the reaction takes place through a two-step mechanism involving (i) a concerted cycloaddition between one monomer and the carbonyl compound to form a four-membered intermediate and (ii) a cycloreversion leading to the thiocarbonyl derivative and phenyl(thioxo)phosphine oxide. Topological analyses confirmed the concertedness and asynchronicity of the process. The second step is the rate-limiting one, and the whole process resembles the currently accepted mechanism for the lithium salt-free Wittig reaction. No zwitterionic intermediates are formed during the reaction, although stabilizing electrostatic interactions are present in initial stages. Phenyl(thioxo)phosphine oxide formed in the thionation reaction is capable of performing a second thionation, although with energy barriers higher than the first one. The driving force of the thionation reactions is the formation of trimers from the resulting monomers. In agreement with experimental observations, the amides are the most reactive when compared with esters, aldehydes, and ketones and the reaction is slightly influenced by the polarity of the solvent. Whereas for amides and esters substituents have little effect, aldehydes and ketones are influenced by both steric and electronic effects.

Multicenter study of epidemiological cutoff values and detection of resistance in Candida spp. to anidulafungin, caspofungin, and micafungin using the Sensititre YeastOne colorimetric method.

Neither breakpoints (BPs) nor epidemiological cutoff values (ECVs) have been established for Candida spp. with anidulafungin, caspofungin, and micafungin when using the Sensititre YeastOne (SYO) broth dilution colorimetric method. In addition, reference caspofungin MICs have so far proven to be unreliable. Candida species wild-type (WT) MIC distributions (for microorganisms in a species/drug combination with no detectable phenotypic resistance) were established for 6,007 Candida albicans, 186 C. dubliniensis, 3,188 C. glabrata complex, 119 C. guilliermondii, 493 C. krusei, 205 C. lusitaniae, 3,136 C. parapsilosis complex, and 1,016 C. tropicalis isolates. SYO MIC data gathered from 38 laboratories in Australia, Canada, Europe, Mexico, New Zealand, South Africa, and the United States were pooled to statistically define SYO ECVs. ECVs for anidulafungin, caspofungin, and micafungin encompassing ≥97.5% of the statistically modeled population were, respectively, 0.12, 0.25, and 0.06 µg/ml for C. albicans, 0.12, 0.25, and 0.03 µg/ml for C. glabrata complex, 4, 2, and 4 µg/ml for C. parapsilosis complex, 0.5, 0.25, and 0.06 µg/ml for C. tropicalis, 0.25, 1, and 0.25 µg/ml for C. krusei, 0.25, 1, and 0.12 µg/ml for C. lusitaniae, 4, 2, and 2 µg/ml for C. guilliermondii, and 0.25, 0.25, and 0.12 µg/ml for C. dubliniensis. Species-specific SYO ECVs for anidulafungin, caspofungin, and micafungin correctly classified 72 (88.9%), 74 (91.4%), 76 (93.8%), respectively, of 81 Candida isolates with identified fks mutations. SYO ECVs may aid in detecting non-WT isolates with reduced susceptibility to anidulafungin, micafungin, and especially caspofungin, since testing the susceptibilities of Candida spp. to caspofungin by reference methodologies is not recommended.

Ortho and para hydrogen dimers on G/SiC(0001): combined STM and DFT study.

The hydrogen (H) dimer structures formed upon room-temperature H adsorption on single layer graphene (SLG) grown on SiC(0001) are addressed using a combined theoretical-experimental approach. Our study includes density functional theory (DFT) calculations for the full (6√3 × 6√3)R30° unit cell of the SLG/SiC(0001) substrate and atomically resolved scanning tunneling microscopy images determining simultaneously the graphene lattice and the internal structure of the H adsorbates. We show that H atoms normally group in chemisorbed coupled structures of different sizes and orientations. We make an atomic scale determination of the most stable experimental geometries, the small dimers and ellipsoid-shaped features, and we assign them to hydrogen adsorbed in para dimers and ortho dimers configuration, respectively, through comparison with the theory.

Immunoglobulins IgG1, IgM and IgA: a synergistic team influencing survival in sepsis.

OBJECTIVE: The impact of endogenous immunoglobulin isotypes on the prognosis of patients with severe sepsis has not been sufficiently explored. The aim of this study was to evaluate the association between immunoglobulin levels in plasma and survival in patients with this condition. DESIGN AND PATIENTS: A prospective multicentre cohort study was conducted. A total of 172 adult patients admitted to the intensive care unit (ICU) with severe sepsis or septic shock were recruited. Patients were classified based on deciles of immunoglobulin concentrations at diagnosis of sepsis. Categorical variables were created and tested for their association with survival during hospitalization in the ICU. RESULTS: Overall, 42 patients died in the ICU during the study. Kaplan-Meier analysis showed that immunoglobulin concentrations below 300 mg dL(-1) for IgG1, 35 mg dL(-1) for IgM and 150 mg dL(-1) for IgA were associated with shorter survival times. Multivariate regression analysis showed that IgG1 < 300 mg dL(-1) was a risk factor for mortality [odds ratio (OR) 2.50, 95% confidence interval (CI) 1.04-6.03; P = 0.042]. The combined presence of IgG1, IgM and IgA levels below the described thresholds had a synergistic impact on mortality risk (OR 5.27, 95% CI 1.41-19.69; P = 0.013). A similar effect was observed for combined low levels of IgG1 and IgA (OR 4.10, 95% CI 1.28-13.12; P = 0.018) and also of IgG1 and IgM (OR 3.10. 95% CI 1.13-8.49; P = 0.028). CONCLUSIONS: The combined presence of low levels of the endogenous immunoglobulins IgG1, IgM and IgA in plasma is associated with reduced survival in patients with severe sepsis or septic shock. Assessment of the concentrations of these immunoglobulins could improve the results of treatment with exogenous immunoglobulins in patients with sepsis.

Theoretical elucidation of the mechanism of the cycloaddition between nitrone ylides and electron-deficient alkenes.

A full theoretical study of the reaction between a novel type of ylide, i.e. nitrone ylides, and alkenes has been carried out. Both concerted and polar stepwise mechanisms have been considered. Only the zwitterionic mechanism predicts correctly the experimentally observed adducts. Depending on the level of theory, the mechanism moves from concerted to polar stepwise, as demonstrated by the corresponding IRC analyses. The regio- and stereoselectivity of the reaction is well explained for both mono- and disubstituted alkenes. In the case of methyl acrylate a pathway leading to the two diastereoisomers obtained experimentally is predicted. For methyl fumarate a stereospecific mechanism is predicted as a consequence of a C-H···O═C interaction present in a Li-tricoordinated transition structure. The stereospecificity in the reaction with methyl maleate comes from a less hindered coordination around the lithium atom. Calculations with B3LYP and M06-2X functionals indicate that only the latter provides energy values in good agreement with experimental findings.

Patient safety certification in a Department of Intensive Care Medicine: our experience with standard UNE 179003:2013.

Systematic and structured methods must be used to ensure that healthcare risks are effectively managed. Spanish standard UNE 179003:2013 provides healthcare organizations with a framework and a systematic protocol for managing patient safety from a clinical and organizational perspective. Furthermore, it is useful in securing an efficient balance among health risk, health outcomes and costs. The UNE 179003:2013 certifies that a clinical service complies with rules and operating procedures aimed at reducing the incidence of adverse events. It also requires mandatory continuous improvement, given that the standard entails frequent monitoring of the risk management system through periodic audits. The aims of this paper are to describe the UNE 179003:2013 certification process in an Intensive Care Unit, propose a risk management program for critical patients, and offer some recommendations regarding its implementation.

Characteristics and type of strabismus associated to macular diplopia. Treatment outcomes.

OBJECTIVE: To study the clinical characteristics of macular diplopia, treatment, and outcome. METHODS: Retrospective descriptive study of cases referred to the ocular motility section of a tertiary hospital with diplopia, diagnosed with macular diplopia between 2022-23. The etiology of the macular pathology and the type of associated strabismus were recorded. The result was considered good if the diplopia improved or was eliminated with the medical or surgical treatment. Follow-up time from the onset of diplopia until data collection was recorded. RESULTS: a total of 19 cases comprised the sample (63.2% women), mean age: 67.16 years. Amblyopia (21.1%), high myopia (47.4%), epirretinal membrane (ERM) (36.8%), neovascular membrane (26.3%), macular hole (10.5%), and lamellar (15.8%), and age macular degeneration (5.3%) were registered. The 47.4% had vertical diplopia, horizontal: 5.3 and 47.4% mixed. The mean horizontal deviation was: 7.3 PD (prism diopters) and vertical: 6.22 PD. Ocular extorsion was observed in 26.3%, and intorsion: 5.3%. Torticollis was present in 15.8%. The treatment consisted of strabismus surgery + Botox (15.8%), strabismus surgery (47.4%), medical treatment with Fresnel prims or Scotch cellophane (36.8%). A 68.4% presented a good result at the end of the study. The mean follow-up was 55.58 months. CONCLUSIONS: Misregistration of macular photoreceptors is the most common cause of binocular diplopia in patients with ERM or other macular pathologies. Most complains of vertical or mixed diplopia. Sensorimotor evaluation of these patients should be thorough. Early diagnosis prevents unnecessary prescription of prism glasses. Surgical and/or medical treatment achieves good results in most cases.

n-Alkanes formed by methyl-methylene addition as a source of meteoritic aliphatics.

Aliphatics prevail in asteroids, comets, meteorites and other bodies in our solar system. They are also found in the interstellar and circumstellar media both in gas-phase and in dust grains. Among aliphatics, linear alkanes (n-CnH2n+2) are known to survive in carbonaceous chondrites in hundreds to thousands of parts per billion, encompassing sequences from CH4 to n-C31H64. Despite being systematically detected, the mechanism responsible for their formation in meteorites has yet to be identified. Based on advanced laboratory astrochemistry simulations, we propose a gas-phase synthesis mechanism for n-alkanes starting from carbon and hydrogen under conditions of temperature and pressure that mimic those found in carbon-rich circumstellar envelopes. We characterize the analogs generated in a customized sputter gas aggregation source using a combination of atomically precise scanning tunneling microscopy, non-contact atomic force microscopy and ex-situ gas chromatography-mass spectrometry. Within the formed carbon nanostructures, we identify the presence of n-alkanes with sizes ranging from n-C8H18 to n-C32H66. Ab-initio calculations of formation free energies, kinetic barriers, and kinetic chemical network modelling lead us to propose a gas-phase growth mechanism for the formation of large n-alkanes based on methyl-methylene addition (MMA). In this process, methylene serves as both a reagent and a catalyst for carbon chain growth. Our study provides evidence of an aliphatic gas-phase synthesis mechanism around evolved stars and provides a potential explanation for its presence in interstellar dust and meteorites.

[Medication errors in Spanish intensive care units]. / Errores de medicación en los servicios de Medicina Intensiva españoles.

OBJECTIVE: To estimate the incidence of medication errors in Spanish intensive care units. DESIGN: Post hoc study of the SYREC trial. A longitudinal observational study carried out during 24 hours in patients admitted to the ICU. SETTING: Spanish intensive care units. PATIENTS: Patients admitted to the intensive care unit participating in the SYREC during the period of study. MAIN VARIABLES OF INTEREST: Risk, individual risk, and rate of medication errors. RESULTS: The final study sample consisted of 1017 patients from 79 intensive care units; 591 (58%) were affected by one or more incidents. Of these, 253 (43%) had at least one medication-related incident. The total number of incidents reported was 1424, of which 350 (25%) were medication errors. The risk of suffering at least one incident was 22% (IQR: 8-50%) while the individual risk was 21% (IQR: 8-42%). The medication error rate was 1.13 medication errors per 100 patient-days of stay. Most incidents occurred in the prescription (34%) and administration (28%) phases, 16% resulted in patient harm, and 82% were considered "totally avoidable". CONCLUSIONS: Medication errors are among the most frequent types of incidents in critically ill patients, and are more common in the prescription and administration stages. Although most such incidents have no clinical consequences, a significant percentage prove harmful for the patient, and a large proportion are avoidable.

Convergence insufficiency with diplopia: Surgical treatment in adults.

OBJECTIVE: To study the outcomes of treatment with central mini-plication of the medial rectus (MR) muscles in adult convergence insufficiency with diplopia. METHODS: The study sample comprised 9 cases (7 women). The length of MR plication was collected. Other variables reported were postsurgical deviation, overcorrections in the early postoperative period and at the end of follow-up, final horizontal deviation at near and at distance vision, diplopia, and mean follow-up from surgery. Surgical outcome was considered to be favorable when diplopia and symptoms were resolved and final exotropia at near was ≤8 pd at the end of follow-up. RESULTS: A central mini-plication of the MR was performed in 9 patients (8 unilateral). Mean (±SD) age was 58.66 (21.39) years. Mean near preoperative deviation: 16.22 (±2.9) pd and distance preoperative deviation: 6.88 (±4) pd Overcorrection at distance vision was recorded in 5 cases; this resolved by 3 months postoperatively. There was not overcorrection at near vision except one case. None of the cases operated on had overcorrection at the end of follow-up. The final horizontal deviation was ≤8 pd at near vision, except for 3 cases (mean: 6.22). Symptoms and diplopia resolved in 8 cases. The mean follow-up was 10.33 months. CONCLUSION: Central mini-plication of 1 or 2 medial rectus muscles can improve the symptoms and signs of exotropia associated with convergence insufficiency when exercises and the prisms are rejected by the patients and when these approaches have not solved the problem.

Supraequatorial displacement with lateral rectus myopexy for treatment of myopic sagging/heavy eye.

PURPOSE: To describe the outcome of the patients diagnosed of sagging/heavy eye associated to myopia, that were operated on with the supra-equatorial displacement with LR myopexy. METHODS: A retrospective study of 9 cases between 2017-2023. The following data were analyzed: horizontal and vertical deviation, diplopia, amblyopia, ductions, ocular torsion, sensorial test, macular pathology, and the orbital magnetic resonance. Treatment was considered Successful if the diplopia was improved or eliminated and a final vertical deviation (VD) ≤5 prism diopters (PD). RESULTS: The mean age (SD) was: 62.11 (4.6) years (100% women). A total of 88.88% presented diplopia. The mean preoperative hypotropia was: 11.33 PD (SD 3.16), and the mean final VD 3.44 PD (SD 3.05). After surgery, the hypotropia was overcorrected in one case, under corrected in 5, and orthophoria was achieved in another three. The technique was associated with surgery of another rectus muscle in 4 subjects. The mean follow-up time after surgery was 34 months (SD 34.62). Six of the 9 patients improved with a vertical deviation ≤5 PD. In 3 patients, the diplopia was eliminated, while in 5 it remained intermittent (three with macular pathology). CONCLUSION: Supra-equatorial displacement with LR myopexy for treatment of myopic sagging/heavy eye, is a therapeutic option if hypotropia is less than 12 PD or the Yokoyama technique is not indicated. A good result was obtained in most cases, although diplopia could only be totally suppressed in three, and another five remained intermittent.

[Nocardia nova brain abscess]. / Absceso cerebral por Nocardia nova.

Nocardia nova is an uncommon pathogen for human beings. We describe an immunocompetent patient who acquired multiple cerebral abscesses. A surgical drainage yielded a sulpha-trimethoprim susceptible N. nova strain. The patient recovered uneventfully after a prolonged treatment with sulpha-trimethoprim.

Strategies to mitigate ammonia and nitrous oxide losses across the manure management chain for intensive laying hen farms.

Circular economy principle aims to achieve sustainable production systems, focusing on the waste valorisation and the reduction of gaseous losses to the atmosphere. Nitrogen (N) compounds in terms of ammonia (NH3) and nitrous oxide (N2O) represent the major losses to the atmosphere of laying hen manure management chain. We present a study aimed to evaluate NH3 and N2O emission and mitigation strategies at housing, storage and land spreading stages. The whole manure management chain was evaluated under different scenarios which combined mitigation strategies of each stage. Two intensive laying hen facilities were involved in the study. Evaluated mitigation strategies were: (i) frequency of manure removal from housing facility, (ii) dried manure storage after passing throughout a manure drying tunnel (MDT) compared to fresh manure storage and (iii) fresh or dried manure incorporation versus surface land application. Increasing the frequency of manure removal from 4 days to 1/3 daily, reduced N losses around 68%. Dried manure storage achieved around 75% reduction in N losses compared to fresh manure storage. Spreading dried manure on grassland surface reduced ≈77% NH3 losses in relation to the emission level reached by fresh manure. The reduction was similar when dried manure was incorporated compared to surface application of fresh manure (≈79%). A 40% reduction in N losses was achieved using the MDT compared to no drying strategy. In the whole manure management chain, the combination of strategies that most reduced N losses was: removal frequency of 1/3 daily, dry storage after passing through the MDT and incorporated land application. These strategies reduced N losses between 40 and 60% compared to the 4 days of removal frequency, fresh storage and surface application of fresh manure.