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Soils located at the Mexican Trans-Volcanic Belt (MTB) have a worrying degree of degradation due to inappropriate management practices. Early indicators of soil changes are very useful to alert about negative impacts of wrong managements on these volcanic soils. The aim of this work was to evaluate the short-term effects (4 years) of different agricultural practices on soil organic matter (SOM) quality and to validate the potential of the selected biochemical properties as optimal early indicators of soil quality in Mexican cultivated Acrisols. During 2002-2005 four agronomic management systems: conventional (Tc); improved conventional (Ti); organic (To) and fallow (Tf) were assayed in plots located at the MTB. An uncultivated soil under grass cover (Sg) was used as reference. Soil samples were collected at 0-10 cm depth and were analysed chemically (soil organic C, total N, water-soluble C and humic C), and biochemically (total and extra-cellular enzyme activity). After 4 years, soil organic C, total N, water-soluble C, and dehydrogenase activity had higher values in To, followed by Ti treatment. A similar response pattern was observed in the extra-cellular enzyme activity. The highest total enzyme activity was found in Sg, followed by Ti and To treatments, and the lowest values appeared in Tc and Tf. To and Ti increased SOM contents of the degraded Acrisols studied, while Tc and Tf managements decreased the quality of these soils. The results showed that the assayed soil enzymes can be used as indicators of quality changes of these Mexican volcanic soils. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Background: Ultraviolet C (UVC) light is a physical method proposed for disinfecting dental impression materials and preventing cross-infections in clinical practice. The investigations have focused on the UVC disinfection potential, but little is known about the consequences on dental materials' properties. This scoping review's objective is to evaluate information about the effect of UVC light on the dimensional stability of dental impression materials., Material and Methods: An electronic search of dental literature in the Medline (via PubMed), Scopus, and Embase databases were systematically searched until July 31 of 2024 following the PRISMA-ScR guidelines. The search strategy was carried out considering three groups of words with indexing terms and Boolean operators. Two reviewers selected the titles and analyzed the abstracts according to the inclusion and exclusion criteria., Results: A total of six articles were included through electronic database searches. Four studies evaluated the dimensional stability by measuring dental casts made from an impression and two studies measured distances on discs made from stainless steel dies. The studies reported the use of polyether, addition and condensation silicones, alginate, and zinc oxide eugenol in the protocols followed. Three of the six included studies compared the effect of UVC light against glutaraldehyde 2% and sodium hypochlorite (1% or 5.25%), one study compared the UVC light against quaternary ammonium salts, phenoxyethanol, alcohol, and ozone, meanwhile another study compared the effect of UVC light against peracetic acid 0.2%, natural polymer of glucosamine and ozonated water. Regarding measuring devices, only one study reported the use of a measuring software, the majority used traveling microscope., Conclusions: Based on the findings, UVC light showed no significant dimensional changes in polyether, addition, and condensation silicones. Key words: Disinfection, dental impression materials, ultraviolet light., Competing Interests: The authors declared no conflict of interest for this review., (Copyright: © 2024 Medicina Oral S.L.)

Oxygen minimum zones (OMZ) represent ~8% of the ocean, with the Pacific as the largest and top expanding area. These regions influence marine ecosystems, promoting anaerobic microbial communities. Nevertheless, only a fraction of microbial diversity has been studied, with fungi being the less explored component. So, herein we analyzed fungal diversity patterns in surface and subsurface sediments along a bathymetric transect using metabarcoding of the ITS1 region in the OMZ of the Mexican Pacific off Mazatlán. We identified 353 amplicon sequence variants (ASV), within the Ascomycota, Basidiomycota, and Rozellomycota. Spatial patterns evidenced higher alpha diversity in nearshore and subsurface subsamples, probably due to temporal fluctuations in organic matter inputs. Small-scale heterogeneity characterized the community with the majority of ASV (269 ASV) occurring in a single subsample, hinting at the influence of local biogeochemical conditions. This baseline data evidenced a remarkable fungal diversity presenting high variation along a bathymetric and vertical transects., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Posadas et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Coastal sediments play a central role in regulating the amount of land-derived reactive nitrogen (N r ) entering the ocean, and their importance becomes crucial in vulnerable ecosystems threatened by anthropogenic activities. Sedimentary denitrification has been identified as the main sink of N r in marine environments, while anaerobic ammonium oxidation with nitrite (anammox) has also been pointed out as a key player in controlling the nitrogen pool in these locations. Collected evidence in the present work indicates that the microbial biota in coastal sediments from Baja California (northwestern Mexico) has the potential to drive anaerobic ammonium oxidation linked to Mn(IV) reduction (manganammox). Unamended sediment showed ammonification, but addition of vernadite (δMnO 2 with nano-crystal size ∼15 Å) as terminal electron acceptor fueled simultaneous ammonium oxidation (up to ∼400 μM of ammonium removed) and production of Mn(II) with a ratio ∆[Mn(II)]/∆[NH 4 + ] of 1.8, which is very close to the stoichiometric value of manganammox (1.5). Additional incubations spiked with external ammonium also showed concomitant ammonium oxidation and Mn(II) production, accounting for ∼30 % of the oxidized ammonium. Tracer analysis revealed that the nitrogen loss associated with manganammox was 4.2 ± 0.4 μg 30 N 2 /g-day, which is 17-fold higher than that related to the feammox process (anaerobic ammonium oxidation linked to Fe(III) reduction, 0.24 ± 0.02 μg 30 N 2 /g-day). Taxonomic characterization based on 16S rRNA gene sequencing revealed the existence of several clades belonging to Desulfobacterota as potential microorganisms catalyzing the manganammox process. These findings suggest that manganammox has the potential to be an additional N r sink in coastal environments, whose contribution to total Nr losses remains to be evaluated., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The unicellular cyanobacterium Candidatus Atelocyanobacterium thalassa (UCYN-A) is a key diazotroph in the global ocean owing to its high N 2 fixation rates and wide distribution in marine environments. Nevertheless, little is known about UCYN-A in oxygen-deficient zones (ODZs), which may be optimal environments for marine diazotrophy. Therefore, the distribution and diversity of UCYN-A were studied in two consecutive years under contrasting phases (La Niña vs. El Niño) of El Niño Southern Oscillation (ENSO) along a transect in the ODZ of the Mexican Pacific upwelling system. Of the three UCYN-A sublineages found, UCYN-A1 and UCYN-A3 were barely detected, whereas UCYN-A2 was dominant in all the stations and showed a wide distribution in both ENSO phases. The presence of UCYN-A was associated with well-oxygenated waters, but it was also found for the first time under suboxic conditions (<20 μM) at the bottom of a shallow coastal station, within the oxygen-poor and nutrient-rich Subsurface Subtropical water mass. This study contributes to the understanding of UCYN-A distribution under different oceanographic conditions associated with ENSO phases in upwelling systems, especially because of the current climate change and increasing deoxygenation in many areas of the world's oceans., (© 2024 The Authors. Environmental Microbiology Reports published by Applied Microbiology International and John Wiley & Sons Ltd.)

Anaerobic ammonium oxidation, associated with both iron (Feammox) and manganese (Mnammox) reduction, is a microbial nitrogen (N) removal mechanism recently identified in natural ecosystems. Nevertheless, the spatial distributions of these non-canonical Anammox (NC-Anammox) pathways and their environmental drivers in subtidal coastal sediments are still unknown. Here, we determined the potential NC-Anammox rates and abundance of dissimilatory metal-reducing bacteria (Acidomicrobiaceae A6 and Geobacteraceae) at different horizons (0-20 cm at 5 cm intervals) of subtidal coastal sediments using the 15 N isotope-tracing technique and molecular analyses. Sediments were collected across three sectors (inlet, transition, and inner) in a coastal lagoon system (Bahia de San Quintin, Mexico) dominated by seagrass meadows. The positive relationship between 30 N 2 production rates and dissimilatory Fe and Mn reduction provided evidence for Feammox's and Mnammox's co-occurrence. N loss through NC-Anammox was detected in subtidal sediments, with potential rates of 0.07-0.62 μg N g -1 day -1 . NC-Anammox process in vegetated sediments tended to be higher than those in adjacent unvegetated ones. NC-Anammox rates showed a subsurface peak (between 5 and 15 cm) in the vegetated sediments but decreased consistently with depth in the adjacent bare bottoms. Thus, the presence/absence of seagrasses and sediment characteristics, particularly the availability of organic carbon and microbiologically reducible Fe(III) and Mn(IV), affected the abundance of dissimilatory metal-reducing bacteria, which mediated NC-Anammox activity and the associated N removal. An annual loss of 32.31 ± 3.57 t N was estimated to be associated with Feammox and Mnammox within the investigated area, accounting for 2.8-4.7% of the gross total import of reactive N from the ocean into the Bahia de San Quintin. Taken as a whole, this study reveals the distribution patterns and controlling factors of the NC-Anammox pathways along a coastal lagoon system. It improves our understanding of the coupling between N and trace metal cycles in coastal environments., Competing Interests: Declaration of competing interest The authors declare that there is no conflict of interest, (Copyright © 2023 Elsevier Ltd. All rights reserved.)

There are few causes of treatable neurodevelopmental diseases described to date. Branched-chain ketoacid dehydrogenase kinase (BCKDK) deficiency causes branched-chain amino acid (BCAA) depletion and is linked to a neurodevelopmental disorder characterized by autism, intellectual disability and microcephaly. We report the largest cohort of patients studied, broadening the phenotypic and genotypic spectrum. Moreover, this is the first study to present newborn screening findings and mid-term clinical outcome. In this cross-sectional study, patients with a diagnosis of BCKDK deficiency were recruited via investigators' practices through a MetabERN initiative. Clinical, biochemical and genetic data were collected. Dried blood spot (DBS) newborn screening (NBS) amino acid profiles were retrieved from collaborating centres and compared to a healthy newborn reference population. Twenty-one patients with BCKDK mutations were included from 13 families. Patients were diagnosed between 8 months and 16 years (mean: 5.8 years, 43% female). At diagnosis, BCAA levels (leucine, valine and isoleucine) were below reference values in plasma and in CSF. All patients had global neurodevelopmental delay; 18/21 had gross motor function (GMF) impairment with GMF III or worse in 5/18, 16/16 intellectual disability, 17/17 language impairment, 12/17 autism spectrum disorder, 9/21 epilepsy, 12/15 clumsiness, 3/21 had sensorineural hearing loss and 4/20 feeding difficulties. No microcephaly was observed at birth, but 17/20 developed microcephaly during follow-up. Regression was reported in six patients. Movement disorder was observed in 3/21 patients: hyperkinetic movements (1), truncal ataxia (1) and dystonia (2). After treatment with a high-protein diet (≥ 2 g/kg/day) and BCAA supplementation (100-250 mg/kg/day), plasma BCAA increased significantly (P < 0.001), motor functions and head circumference stabilized/improved in 13/13 and in 11/15 patients, respectively. Among cases with follow-up data, none of the three patients starting treatment before 2 years of age developed autism at follow-up. The patient with the earliest age of treatment initiation (8 months) showed normal development at 3 years of age. NBS in DBS identified BCAA levels significantly lower than those of the normal population. This work highlights the potential benefits of dietetic treatment, in particular early introduction of BCAA. Therefore, it is of utmost importance to increase awareness about this treatable disease and consider it as a candidate for early detection by NBS programmes., (© The Author(s) 2023. Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Dissolved oxygen regulates microbial distribution and nitrogen cycling and, therefore, ocean productivity and Earth's climate. To date, the assembly of microbial communities in relation to oceanographic changes due to El Niño Southern Oscillation (ENSO) remains poorly understood in oxygen minimum zones (OMZ). The Mexican Pacific upwelling system supports high productivity and a permanent OMZ. Here, the spatiotemporal distribution of the prokaryotic community and nitrogen-cycling genes was investigated along a repeated transect subjected to varying oceanographic conditions associated with La Niña in 2018 and El Niño in 2019. The community was more diverse during La Niña and in the aphotic OMZ, dominated by the Subtropical Subsurface water mass, where the highest abundances of nitrogen-cycling genes were found. The largest proportion of the Gulf of California water mass during El Niño provided warmer, more oxygenated, and nutrient-poor waters towards the coast, leading to a significant increase of Synechococcus in the euphotic layer compared with the opposite conditions during La Niña. These findings suggest that prokaryotic assemblages and nitrogen genes are linked to local physicochemical conditions (e.g. light, oxygen, nutrients), but also to oceanographic fluctuations associated with ENSO phases, indicating the crucial role of climate variability in microbial community dynamics in this OMZ., (© 2023 The Authors. Environmental Microbiology published by Applied Microbiology International and John Wiley & Sons Ltd.)

Purpose: To evaluate the surface roughness of glazed and polished monolithic ceramic materials and to use this as a baseline for comparison after adjustment and polishing with both the recommended kit for the specific materials as well as interchanged polishing kits., Material and Methods: Flat ceramic specimens (n = 150) were fabricated from IPS ZirCAD Prime, IPS E.max, and Vitabloc Mark II. The specimens were adjusted and polished using either the proprietary polishing kit for the material or interchanged kits. The surface roughness was objectively assessed using Atomic Force Microscopy (AFM) and profilometer. Subjective assessment of surface finish was performed using a scanning electron microscope (SEM). Gravimetric weight loss of each sample was measured before and after polishing using a digital microscale. The mean surface roughness and standard deviation was calculated for each ceramic- polisher pair. A factorial ANOVA was used to compare the mean surface roughness values in nanometers between multiple groups (α = 0.05). The subjective results from the SEM were reported as descriptive statistics RESULTS: The zirconia polishing system produced surfaces with the lowest surface roughness regardless of the ceramic material. The polisher-ceramic combination was found to have a statistically significant effect on both Ra and RMS values when the AFM was used (p = 0.039 and 0.010, respectively)., Conclusion: The zirconia polishing system resulted in the lowest surface roughness values regardless of ceramic materials tested. The zirconia polishing system also did not result in significant gravimetric weight loss regardless of the ceramic material used., (© 2022 by the American College of Prosthodontists.)

Introduction: To ensure the quality of the new-born screening (NBS), our laboratory reviewed the analytical procedure to detect subjective steps that may represent a risk to the patient. Two subjective activities were identified in the extra-analytical phases: the classification of dried blood spots (DBS) according to their quality and the assignment of haemoglobin patterns. To keep these activities under control, inter-rater studies were implemented. This study aimed to evaluate the inter-rater reliability and the effectiveness of the measures taken to improve the agreement between observers, to assure NBS results' quality., Materials and Methods: Dried blood spots specimens were used for the inter-rater studies. Ten studies were performed to assess DBS quality classification, and four to assess the assignment of haemoglobin patterns. Krippendorff's alpha test was used to estimate inter-rater reliability. Causes were investigated when alpha values were below 0.80., Results: For both activities, the reliability obtained in the first studies was inadequate. After investigation, we detected that the criterion to classify a DBS as scant was not consolidated, and also a lack of consensus on whether or not to report Bart's haemoglobin depending on its percentage. Alpha estimates became higher once the training was reinforced and a consensus about the appropriate criteria to be applied was reached., Conclusion: Inter-rater reliability assessment helped us to ensure the quality of subjective activities that could add variability to NBS results. Furthermore, the evolution of the alpha value over time allowed us to verify the effectiveness of the measures adopted., Competing Interests: Potential conflict of interest None declared., (Croatian Society of Medical Biochemistry and Laboratory Medicine.)

Introduction: Instability of the distal radioulnar joint (DRUJ) commonly results from traumatic disruption of the distal radioulnar ligaments of the triangular fibrocartilage complex (TFCC). Treatment of this rupture typically requires immobilization of the wrist and elbow for a period of 6 to 8 weeks. This study evaluated the hypothesis that treatment of DRUJ instability with dynamic stabilization would allow early mobilization of both the radiocarpal and distal radioulnar joints by the first postoperative week without compromising restoration of TFCC integrity., Materials and Methods: Between September 2017 and January 2019, a retrospective study was conducted on 22 patients presenting with DRUJ instability confirmed by intraoperative Ballottement testing. Once instability was confirmed, dynamic surgical stabilization was performed, followed by one week of short cast immobilization. Arthrographic computed tomography (CT) of each patients' affected wrist was performed 4 months later to evaluate TFCC integrity. The recovery of patients was monitored at 1, 3, 6, and 12 months after surgery using the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire, Ballottement test, and evaluation of radioulnar join range of motion (ROM), pain, and complications., Results: All patients were followed postoperatively for a mean of 13.5 months. After 1 month, all patients exhibited satisfactory range of motion and DRUJ stability. By 3 months, Ballottement tests were negative in 21 of 22 patients, with instability persisting in only 1 patient. At 4 months, CT arthrography contrast leakage (indicative of a TFCC tear) was observed in 5 of 20 patients. Upon reexamination a mean of 10.5 months later, the TFCC tears of these patients had healed in 2 cases (with foveal tears), while no difference in contrast leakage was observed for the other 3 cases (with horizontal or central tears). Revision surgery for implant related complications was performed in 2 cases., Conclusion: Acute DRUJ instability treated with dynamic stabilization led to satisfactory clinical outcomes in terms of range of motion, pain relief and joint stability, allowing DRUJ movement from the first postoperative week. This technique represents a simple, reproducible and minimally invasive procedure with a low rate of implant related complications., Competing Interests: Declaration of Competing Interest None., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Background: The objective of this study was to compare dentists' perceptions of gloss values of composite specimens with increased levels and to identify the gloss value considered to be clinically acceptable., Methods: Disk-shaped composite specimens were finished and polished 3 ways: metallurgically using silicon carbide papers and alumina paste, manually using Enhance finisher and PoGo polisher (EP) (Dentsply Sirona), and manually using Sof-Lex (SLex) disks (3M). Specimens were produced with surface gloss ranging from 0 through 100 gloss units (GU) in increments of approximately 10 GU as measured with a glossmeter. A GU of 0 was nonglossy, and a GU of 100 was perfectly glossy. Ten dentists evaluated the specimens, ranking them in order from low to high gloss and in 4 groups: low (dull or rough), medium (moderate gloss, clinically unacceptable), high (glossy, clinically acceptable), and superior gloss. The authors performed Spearman correlation analysis (α = 0.05)., Results: For each finish and polish method, there was an excellent correlation between the machine-measured (actual) gloss ranks and the clinician-evaluated gloss ranks (r 2 ≥ 0.95). There was no difference in perception of surface gloss of the composite when metallurgically polished (with silicon carbide papers and alumina paste) or polished with EP to the same GU. There was a slight difference in gloss perception when comparing the 2 different commercial polishing systems., Conclusions: Ten dentists consistently perceived gloss of 40 through 50 GU as clinically acceptable. However, the composite was considered clinically acceptable at a lower gloss (40 GU) when polished with SLex disks than when polished with EP or metallurgically (50 GU)., Practical Implications: Gloss values of 40 through 50 GU are considered to be clinically acceptable for resin composites., (Copyright © 2021 American Dental Association. Published by Elsevier Inc. All rights reserved.)

Background: Alteration of vitamin B 12 metabolism can be genetic or acquired, and can result in anemia, failure to thrive, developmental regression and even irreversible neurologic damage. Therefore, early diagnosis and intervention is critical. Most of the neonatal cases with acquired vitamin B 12 deficiency have been detected by clinical symptoms and only few of them trough NBS programs. We aim to assess the usefulness of the second-tier test: methylmalonic acid (MMA), methylcitric acid (MCA) and homocysteine (Hcys) in our newborn screening program and explore the implications on the detection of cobalamin (vitamin B 12 ) related disorders, both genetic and acquired conditions., Methods: A screening strategy using the usual primary markers followed by the analysis of MMA, MCA and Hcys as second tier-test in the first dried blood spot (DBS) was developed and evaluated., Results: During the period 2015-2018 a total of 258,637 newborns were screened resulting in 130 newborns with acquired vitamin B 12 deficiency (incidence 1:1989), 19 with genetic disorders (incidence 1:13,613) and 13 were false positive. No false negatives were notified. Concerning the second-tier test, the percentage of cases with MMA above the cut-off levels, both for genetic and acquired conditions was very similar (58% and 60%, respectively). Interestingly, the percentage of cases with increased levels of Hcys was higher in acquired conditions than in genetic disorders (87% and 47%, respectively). In contrast, MCA was high only in 5% of the acquired conditions versus in 53% of the genetic disorders, and it was always very high in all patients with propionic acidemia., Conclusions: When screening for methylmalonic acidemia and homocystinuria, differential diagnosis with acquired vitamin B 12 deficiency should be done. The results of our strategy support the inclusion of this acquired condition in the NBS programs, as it is easily detectable and allows the adoption of corrective measures to avoid the consequences of its deficiency.

Purpose: Although fifth metacarpal neck fractures are typically treated nonsurgically, most often with closed reduction and orthosis immobilization, cast immobilization may not improve outcomes compared with buddy taping without reduction. The aim of this study was to compare functional outcomes of buddy taping versus reduction and cast immobilization in patients with fifth metacarpal neck fractures., Methods: Adult patients with acute fifth metacarpal neck fractures with less than 70º volar angulation and without rotational deformity were randomly assigned to be treated either with buddy taping or a cast after closed reduction. The primary outcome was the Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire score at 9 weeks. Secondary outcomes included the DASH score at 3 weeks and 1 year, range of motion of the metacarpophalangeal joint, pain, grip strength, return to work, radiographic angulation, and complication rate., Results: We recruited 72 patients between August 2016 and January 2018. After 3 weeks, the DASH score was significantly lower for patients treated with buddy taping (19.7 ± 19.7) compared with cast immobilization (44.6 ± 15.0). At 9 weeks, clinical outcomes in the buddy taping group were better in terms of range of motion and DASH score, with a mean difference of 6.3 points, which did not exceed the minimally clinically important difference. There were more complications in the cast immobilization group. Fracture angulation after reduction was followed by a loss of reduction at 3 weeks' follow-up and equivalent residual radiographic volar angulation was observed at 3 and 9 weeks after injury in both groups. Duration of time off from work was 28 days shorter with buddy taping compared with cast treatment., Conclusions: There is no benefit to reduction and orthosis immobilization of fifth metacarpal neck fractures with an initial angulation less than 70°. Use of buddy taping and early mobilization had good clinical results as well as significant improvement in time lost from work., Type of Study/level of Evidence: Therapeutic I., (Copyright © 2020 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.)

Microbial communities within oxygen minimum zones (OMZs) are crucial drivers of marine biogeochemical cycles; however, we still lack an understanding of how these communities are distributed across an OMZ. We explored vertical (from 5 to 500 m depth) and horizontal (coast to open ocean) distribution of bacterioplankton and its relationships with the main oceanographic conditions in three transects of the tropical Mexican Pacific OMZ. The distribution of the microbial diversity and the main clades changed along the transition from oxygen-rich surface water to the OMZ core, demonstrating the sensitivity of key bacterial groups to deoxygenation. The euphotic zone was dominated by Synechococcales, followed by Flavobacteriales, Verrucomicrobiales, Rhodobacterales, SAR86, and Cellvibrionales, whereas the OMZ core was dominated by SAR11, followed by SAR406, SAR324, SAR202, UBA10353 marine group, Thiomicrospirales and Nitrospinales. The marked environmental gradients along the water column also supported a high potential for niche partitioning among OMZ microorganisms. Additionally, in the OMZ core, bacterial assemblages from the same water mass were more similar to each other than those from another water mass. There were also important differences between coastal and open-ocean communities: Flavobacteriales, Verrucomicrobiales, Rhodobacterales, SAR86, and Cellvibrionales were more abundant in coastal areas, while Synechococcales, SAR406, SAR324, SAR202, UBA10353 marine group, and Thiomicrospirales were more abundant in the open ocean. Our results suggest a biogeographic structure of the bacterioplankton in this OMZ region, with limited community mixing across water masses, except in upwelling events, and little dispersion of the community by currents in the euphotic zone.

Microbial communities play a central role in the N cycle of oceanic oxygen minimum zones (OMZs), such as in the Eastern Tropical North Pacific (ETNP). We explored the spatial distribution of the genetic potential for ammonia oxidation (amoA gene for bacteria and archaea), denitrification (nirS and nirK), anaerobic ammonium oxidation (anammox) (hzo) and dissimilarity nitrate reduction to ammonia (DNRA) (nrfA) and their relationships with the hydrological variables and isotopic composition of nitrate in the ETNP off Mexico. Oxygen concentration, the availability of N chemical forms and the upwelling shaped the distribution of N cycling genes along the water column. The high abundance of N genes and the isotopic composition of nitrate suggest the N cycling is very dynamic in the OMZ core. The accumulation of nitrite, the high abundance of archaeal amoA genes, and the deviation of the N and O isotopes of nitrate from the expected 1:1 ratio for nitrate reduction in the upper portion of this OMZ indicate that nitrification is a relevant process that fuels the denitrifier community. Conversely, the high abundances of nitrate, ammonium and nrfA genes in the deeper layer indicate that DNRA is a crucial process enhancing anammox there. These results show the need for more detailed studies of the N processes in OMZs., (© FEMS 2019.)

Symbiotic relationships between host and microbiome can play a major role in local adaptation. Previous studies with freshwater organisms have shown that microbiome performs numerous important biochemical functions for the host, playing a key role in metabolism, physiology or health. Experimental studies in fish groups have found an effect of enzymatic activity of gut microbiota on a variety of metabolic processes. The goal of this study was to compare stomach microbiome from cave and surface Astyanax mexicanus, in order to evaluate the potential response of microbiota to contrasting environmental conditions and physiological adaptations of the host. Stomach microbiota was obtained from three different populations: Pachón cave, and two surface rivers (Rascón and Micos rivers). The stomach microbiome was analyzed using the Ion 16S Metagenomic kit considering seven variable regions: V2, V3, V4, V6-7, V8 and V9. A high diversity was observed across samples, including 16 phyla, 120 families and 178 genera. Gammaproteobacteria, Firmicutes, Bacteroidetes and Betaproteobacteria were the most abundant phyla across the samples. Although the relative abundance of the core OTUs at genus level were highly contrasting among populations, we did not recover differences in stomach microbiome between contrasting habitats (cave vs. surface rivers). Rather, we observed a consistent association between β-diversity and dissolved oxygen concentration in water. Therefore, and unexpectedly, the microbiota of A. mexicanus is not linked with the contrasting conditions of the habitat considered here but is related to water parameters., Competing Interests: The authors declare there are no competing interests.

Several studies have shown that rainfall seasonality, soil heterogeneity, and increased nitrogen (N) deposition may have important effects on tropical forest function. However, the effects of these environmental controls on soil microbial communities in seasonally dry tropical forests are poorly understood. In a seasonally dry tropical forest in the Yucatan Peninsula (Mexico), we investigated the influence of soil heterogeneity (which results in two different soil types, black and red soils), rainfall seasonality (in two successive seasons, wet and dry), and 3 years of repeated N enrichment on soil chemical and microbiological properties, including bacterial gene content and community structure. The soil properties varied with the soil type and the sampling season but did not respond to N enrichment. Greater organic matter content in the black soils was associated with higher microbial biomass, enzyme activities, and abundances of genes related to nitrification ( amoA ) and denitrification ( nirK and nirS ) than were observed in the red soils. Rainfall seasonality was also associated with changes in soil microbial biomass and activity levels and N gene abundances. Actinobacteria , Proteobacteria , Firmicutes , and Acidobacteria were the most abundant phyla. Differences in bacterial community composition were associated with soil type and season and were primarily detected at higher taxonomic resolution, where specific taxa drive the separation of communities between soils. We observed that soil heterogeneity and rainfall seasonality were the main correlates of soil bacterial community structure and function in this tropical forest, likely acting through their effects on soil attributes, especially those related to soil organic matter and moisture content. IMPORTANCE Understanding the response of soil microbial communities to environmental factors is important for predicting the contribution of forest ecosystems to global environmental change. Seasonally dry tropical forests are characterized by receiving less than 1,800 mm of rain per year in alternating wet and dry seasons and by high heterogeneity in plant diversity and soil chemistry. For these reasons, N deposition may affect their soils differently than those in humid tropical forests. This study documents the influence of rainfall seasonality, soil heterogeneity, and N deposition on soil chemical and microbiological properties in a seasonally dry tropical forest. Our findings suggest that soil heterogeneity and rainfall seasonality are likely the main factors controlling soil bacterial community structure and function in this tropical forest. Nitrogen enrichment was likely too low to induce significant short-term effects on soil properties, because this tropical forest is not N limited., (Copyright © 2018 American Society for Microbiology.)

Objective: The purpose of this study was to assess the gelation and polymerization time of three polyvinyl siloxane (PVS) putty materials and to determine if those times were affected by nitrile gloves under different conditions., Materials and Methods: Ten specimens (n=10) were obtained for each PVS putty material (Express STD, 3M ESPE; Extrude Xtra, Kerr and Exafast, GC) and tested under different conditions (gloves washed, gloves unwashed and hands contaminated). The gelation and polymerization time were measured using an oscillating rheometer and recorded for 400 s at 37°C to simulate the oral environment., Results: The mean gelation time of hand contaminated specimens was 157.50 minutes and was significantly slower than that by using nitrile washed gloves (mean=117.94, p=.004) and by using unwashed gloves (mean=99.46, p⟨0.001). Unwashed gloves had significantly quicker gelation times compared to washed gloves (p=.046). The gelation time was significantly delayed with Exafast compared to Extrude Xtra and Express STD across all the different types of glove conditions (p⟨0.043). No significant differences were observed between polymerization time with Exafast and Extrude Xtra Putty., Conclusions: Extrude Xtra putty material had significantly better performance than GC Exafast and Express. Hand contaminated specimens were affected by the gelation/polymerization time., (Copyright© 2018 Dennis Barber Ltd.)

The scope of newborn screening (NBS) programs is continuously expanding. NBS programs are secondary prevention interventions widely recognized internationally in the "field of Public Health." These interventions are aimed at early detection of asymptomatic children affected by certain diseases, with the objective to establish a definitive diagnosis and apply the proper treatment to prevent further complications and sequelae and ensure a better quality of life. The most significant event in the history of neonatal screening was the discovery of phenylketonuria in 1934. This disease has been the paradigm of inherited metabolic diseases. The next paradigm was the introduction of tandem mass spectrometry in the NBS programs that make possible the simultaneous measurement of several metabolites and consequently, the detection of several diseases in one blood spot and in an unique analysis. We aim to review the current situation of neonatal screening in 2016 worldwide and show scientific evidence of the benefits for some diseases. We will also discuss future challenges. It should be taken into account that any consideration to expand an NBS panel should involve a rigorous process of decision-making that balances benefits against the risks of harm., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Arid ecosystems are characterized by high spatial heterogeneity, and the variation among vegetation patches is a clear example. Soil biotic and abiotic factors associated with these patches have also been well documented as highly heterogeneous in space. Given the low vegetation cover and little precipitation in arid ecosystems, soil microorganisms are the main drivers of nutrient cycling. Nonetheless, little is known about the spatial distribution of microorganisms and the relationship that their diversity holds with nutrients and other physicochemical gradients in arid soils. In this study, we evaluated the spatial variability of soil microbial diversity and chemical parameters (nutrients and ion content) at local scale (meters) occurring in a gypsum-based desert soil, to gain knowledge on what soil abiotic factors control the distribution of microbes in arid ecosystems. We analyzed 32 soil samples within a 64 m(2) plot and: (a) characterized microbial diversity using T-RFLPs of the bacterial 16S rRNA gene, (b) determined soil chemical parameters, and (c) identified relationships between microbial diversity and chemical properties. Overall, we found a strong correlation between microbial composition heterogeneity and spatial variation of cations (Ca(2), K(+)) and anions (HCO[Formula: see text], Cl(-), SO[Formula: see text]) content in this small plot. Our results could be attributable to spatial differences of soil saline content, favoring the patchy emergence of salt and soil microbial communities., Competing Interests: Valeria Souza and Luis E. Eguiarte are Academic Editors for PeerJ.

Soil microorganisms play important roles in nitrogen cycling within forest ecosystems. Current research has revealed that a wider variety of microorganisms, with unexpected diversity in their functions and phylogenies, are involved in the nitrogen cycle than previously thought, including nitrogen-fixing bacteria, ammonia-oxidizing bacteria and archaea, heterotrophic nitrifying microorganisms, and anammox bacteria, as well as denitrifying bacteria, archaea, and fungi. However, the vast majority of this research has been focused in temperate regions, and relatively little is known regarding the ecology of nitrogen-cycling microorganisms within tropical and subtropical ecosystems. Tropical forests are characterized by relatively high precipitation, low annual temperature fluctuation, high heterogeneity in plant diversity, large amounts of plant litter, and unique soil chemistry. For these reasons, regulation of the nitrogen cycle in tropical forests may be very different from that of temperate ecosystems. This is of great importance because of growing concerns regarding the effect of land use change and chronic-elevated nitrogen deposition on nitrogen-cycling processes in tropical forests. In the context of global change, it is crucial to understand how environmental factors and land use changes in tropical ecosystems influence the composition, abundance and activity of key players in the nitrogen cycle. In this review, we synthesize the limited currently available information regarding the microbial communities involved in nitrogen fixation, nitrification and denitrification, to provide deeper insight into the mechanisms regulating nitrogen cycling in tropical forest ecosystems. We also highlight the large gaps in our understanding of microbially mediated nitrogen processes in tropical forest soils and identify important areas for future research.

Niemann-Pick type C (NPC) is a progressive neurodegenerative disease characterized by lysosomal/endosomal accumulation of unesterified cholesterol and glycolipids. Recent studies have shown that plasma cholestane-3β,5α,6β-triol (CT) and 7-ketocholesterol (7-KC) could be potential biomarkers for the diagnosis of NPC patients. We aimed to know the sensitivity and specificity of these biomarkers for the diagnosis of NPC compared with other diseases that can potentially lead to oxysterol alterations. We studied 107 controls and 122 patients including 16 with NPC, 3 with lysosomal acid lipase (LAL) deficiency, 8 with other lysosomal diseases, 5 with galactosemia, 11 with cerebrotendinous xanthomatosis (CTX), 3 with Smith-Lemli-Opitz, 14 with peroxisomal biogenesis disorders, 19 with unspecific hepatic diseases, 13 with familial hypercholesterolemia, and 30 with neurological involvement and no evidence of an inherited metabolic disease. CT and 7-KC were analyzed by HPLC-ESI-MS/MS as mono-dimethylglycine derivatives. Levels of 7-KC were high in most of the studied diseases, whereas those of CT were only high in NPC, LAL, and CTX patients. Consequently, although CT is a sensitive biomarker of NPC disease, including those cases with doubtful filipin staining, it is not specific. 7-KC is a very unspecific biomarker., (Copyright © 2015 by the American Society for Biochemistry and Molecular Biology, Inc.)

Understanding the response of bacterial communities to environmental change is extremely important in predicting the effect of biogeochemical modifications in ecosystem functioning. The Cuatro Cienegas Basin is an ancient oasis in the Mexican Chihuahuan desert that hosts a wide diversity of microbial mats and stromatolites that have survived in extremely oligotrophic pools with nearly constant conditions. However, thus far, the response of these unique microbial communities to long-term environmental disturbances remains unexplored. We therefore studied the compositional stability of these bacterial mat communities by using a replicated (3x) mesocosm experiment: a) Control; b) Fluct: fluctuating temperature; c) 40C: increase to 40 ºC; d) UVplus: artificial increase in UV radiation; and f) UVmin: UV radiation protection. In order to observe the changes in biodiversity, we obtained 16S rRNA gene clone libraries from microbial mats at the end of the experiment (eight months) and analyzed them using multivariate and phylogenetic tools. Sequences were assigned to 13 major lineages, among which Cyanobacteria (38.8%) and Alphaproteobacteria (25.5%) were the most abundant. The less extreme treatments (Control and UVmin) had a more similar composition and distribution of the phylogenetic groups with the natural pools than the most extreme treatments (Fluct, 40C, and UVplus), which showed drastic changes in the community composition and structure, indicating a different community response to each environmental disturbance. An increase in bacterial diversity was found in the UVmin treatment, suggesting that protected environments promote the establishment of complex bacterial communities, while stressful environments reduce diversity and increase the dominance of a few Cyanobacterial OTUs (mainly Leptolyngbya sp) through environmental filtering. Mesocosm experiments using complex bacterial communities, along with multivariate and phylogenetic analyses of molecular data, can assist in addressing questions about bacterial responses to long-term environmental stress.

Understanding the changes of aquatic microbial community composition in response to changes in temperature and ultraviolet irradiation is relevant for predicting biogeochemical modifications in the functioning of natural microbial communities under global climate change scenarios. Herein we investigate shifts in the bacterioplankton composition in response to long-term changes in temperature and UV radiation. For this purpose, 15 mesocosms were seeded with composite aquatic microbial communities from natural pools within the Cuatro Cienegas Basin (Mexican Chihuahuan desert) and were subject to different temperatures and UV conditions. 16S rRNA gene clone libraries were obtained from water samples at the mid-point (4 months) and the end of the experiment (8 months). An increase in bacterial diversity over time was found in the treatment of constant temperature and UV protection, which suggests that stable environments promote the establishment of complex and diverse bacterial community. Drastic changes in the phylogenetic bacterioplankton composition and structure were observed in response to fluctuating temperature and increasing UV radiation and temperature. Fluctuating temperature induced the largest decrease of bacterial richness during the experiment, indicating that frequent temperature changes drive the reduction in abundance of several species, most notably autotrophs. The long-term impact of these environmental stresses reduced diversity and selected for generalist aquatic bacterial populations, such as Porphyrobacter. These changes at the community level occur at an ecological time scale, suggesting that under global warming scenarios cascade effects on the food web are possible if the microbial diversity is modified.

Recent investigations have suggested creatine (Cr) as an additional biomarker of mitochondrial diseases. With the aim of corroborating previous findings, we have studied plasma Cr in a cohort of 33 patients with different mitochondrial diseases. Cr was clearly increased in 9 out of 33 patients. Therefore, positive patients represent only 28% of the total number, suggesting that Cr is not a sensitive biomarker of mitochondrial diseases although it does present an acceptable specificity (83%). High plasma Cr, together with other biomarkers, might be useful to reinforce the diagnosis of mitochondrial diseases., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Microbial communities are responsible for important ecosystem processes, and their activities are regulated by environmental factors such as temperature and solar ultraviolet radiation. Here we investigate changes in aquatic microbial community structure, diversity, and evenness in response to changes in temperature and UV radiation. For this purpose, 15 mesocosms were seeded with both microbial mat communities and plankton from natural pools within the Cuatro Cienegas Basin (Mexico). Clone libraries (16S rRNA) were obtained from water samples at the beginning and at the end of the experiment (40 days). Phylogenetic analysis indicated substantial changes in aquatic community composition and structure in response to temperature and UV radiation. Extreme treatments with elevation in temperature or UV radiation reduced diversity in relation to the Control treatments, causing a reduction in richness and increase in dominance, with a proliferation of a few resistant operational taxonomic units. Each phylum was affected differentially by the new conditions, which translates in a differential modification of ecosystem functioning. This suggests that the impact of environmental stress, at least at short term, will reshape the aquatic bacterial communities of this unique ecosystem. This work also demonstrates the possibility of designing manageable synthetic microbial community ecosystems where controlled environmental variables can be manipulated. Therefore, microbial model systems offer a complementary approach to field and laboratory studies of global research problems associated with the environment.

Mucopolysaccharidosis type IVA (Morquio A) is an inherited metabolic disease with autosomal recessive inheritance. The pathology is due to a deficient activity of N-acetylgalactosamine-6-sulfate-sulfatase, which is involved in the degradation of keratan sulfate and chondroitin-6-sulfate. To date more than 150 mutations have been described in the GALNS gene in different populations. The aim of this study was to analyze the mutations and polymorphisms in Spain in order to know the epidemiology of our population and also to offer genetic counseling to affected families. We found 30 mutant alleles in the 15 families analyzed completing all the genotypes. Most of the mutations that we found were missense mutations, six of which were novel: p.S74F, p.E121D, p.Y254C, p.E260K, p.T394P and p.N495Y; we also found a small deletion (c.1142delC) and a probable deep intronic mutation that causes the loss of exon 5 (c.423&#95;566del) found in cDNA. Both mutations are described in this study for the first time. We also identified 20 polymorphisms previously reported and 2 novel ones: (c.633+222T/C and c.898+25C>G). In conclusion, we have identified the mutations responsible for Mucopolysaccharidosis IV A in Spain. We found great allelic heterogeneity, as occurs in other populations, which hinders the establishment of genotype-phenotype correlations in Spain. This study has been very useful for genetic counseling to the affected families., (Copyright © 2012. Published by Elsevier Inc.)