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1.
Eur Radiol ; 34(3): 1790-1803, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37646815

RESUMO

OBJECTIVES: The Prostate Imaging for Recurrence Reporting (PI-RR) system has been recently proposed to promote standardisation in the MR assessment of prostate cancer (PCa) local recurrence after radical prostatectomy (RP) and radiation therapy (RT). This study aims to evaluate PI-RR's diagnostic accuracy, assess the inter-observer reliability among readers with variable experience, and correlate imaging results with anatomopathological and laboratory parameters. METHODS: Patients who underwent a pelvic MRI for suspicion of PCa local recurrence after RP or RT were retrospectively enrolled (October 2017-February 2020). PI-RR scores were independently assessed for each patient by five readers with variable experience in prostate MRI (two senior and three junior radiologists). Biochemical data and histopathological features were collected. The reference standard was determined through biochemical, imaging, or histopathological follow-up data. Reader's diagnostic performance was assessed using contingency tables. Cohen's kappa coefficient (κ) and intraclass correlation coefficient (ICC) were calculated to measure inter-observer reliability. RESULTS: The final cohort included 120 patients (median age, 72 years [IQR, 62-82]). Recurrence was confirmed in 106 (88.3%) patients. Considering a PI-RR score ≥ 3 as positive for recurrence, minimum and maximum diagnostic values among the readers were as follows: sensitivity 79-86%; specificity 64-86%; positive predictive value 95-98%; negative predictive value 33-46%; accuracy 79-87%. Regardless of reader's level of experience, the inter-observer reliability resulted good or excellent (κ ranges across all readers: 0.52-0.77), and ICC was 0.8. Prostate-specific antigen (PSA) velocity, baseline-PSA, and trigger-PSA resulted predictive of local recurrence at imaging. CONCLUSIONS: The PI-RR system is an effective tool for MRI evaluation of PCa local recurrence and facilitates uniformity among radiologists. CLINICAL RELEVANCE STATEMENT: This study confirmed the PI-RR system's good diagnostic accuracy for the MRI evaluation of PCa local recurrences. It showed high reproducibility among readers with variable experience levels, validating it as a promising standardisation tool for assessing patients with biochemical recurrence. KEY POINTS: • In this retrospective study, the PI-RR system revealed promising diagnostic performances among five readers with different experience (sensitivity 79-86%; specificity 64-86%; accuracy 79-87%). • The inter-observer reliability among the five readers resulted good or excellent (κ ranges: 0.52-0.77) with an intraclass correlation coefficient of 0.8. • The PI-RR assessment score may facilitate standardisation and generalizability in the evaluation of prostate cancer local recurrence among radiologists.


Assuntos
Próstata , Neoplasias da Próstata , Masculino , Humanos , Idoso , Próstata/patologia , Antígeno Prostático Específico , Estudos Retrospectivos , Reprodutibilidade dos Testes , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/cirurgia , Neoplasias da Próstata/patologia , Imageamento por Ressonância Magnética/métodos , Prostatectomia/métodos
2.
Sensors (Basel) ; 23(21)2023 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-37960497

RESUMO

Heart diseases rank among the most fatal health concerns globally, with the majority being preventable through early diagnosis and effective treatment. Electrocardiogram (ECG) analysis is critical in detecting heart diseases, as it captures the heart's electrical activities. For continuous monitoring, wearable electrocardiographic devices must ensure user comfort over extended periods, typically 24 to 48 h. These devices demand specialized algorithms with low computational complexity to accommodate memory and power consumption constraints. One of the most crucial aspects of ECG signals is accurately detecting heartbeat intervals, specifically the R peaks. In this study, we introduce a novel algorithm designed for wearable devices, offering two primary attributes: robustness against noise and low computational complexity. Our algorithm entails fitting a least-squares parabola to the ECG signal and adaptively shaping it as it sweeps through the signal. Notably, our proposed algorithm eliminates the need for band-pass filters, which can inadvertently smooth the R peaks, making them more challenging to identify. We compared the algorithm's performance using two extensive databases: the meta-database QT database and the BIH-MIT database. Importantly, our method does not necessitate the precise localization of the ECG signal's isoelectric line, contributing to its low computational complexity. In the analysis of the QT database, our algorithm demonstrated a substantial advantage over the classical Pan-Tompkins algorithm and maintained competitiveness with state-of-the-art approaches. In the case of the BIH-MIT database, the performance results were more conservative; they continued to underscore the real-world utility of our algorithm in clinical contexts.


Assuntos
Cardiopatias , Dispositivos Eletrônicos Vestíveis , Humanos , Processamento de Sinais Assistido por Computador , Eletrocardiografia/métodos , Algoritmos
3.
Viruses ; 15(9)2023 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-37766248

RESUMO

(1) Background: COVID-19 has evolved during seven epidemic waves in Spain. Our objective was to describe changes in mortality and severity in our hospitalized patients. (2) Method: This study employed a descriptive, retrospective approach for COVID-19 patients admitted to the Hospital de Fuenlabrada (Madrid, Spain) until 31 December 2022. (3) Results: A total of 5510 admissions for COVID-19 were recorded. The first wave accounted for 1823 (33%) admissions and exhibited the highest proportion of severe patients: 65% with bilateral pneumonia and 83% with oxygen saturation under 94% during admission and elevated levels of CRP, IL-6, and D-dimer. In contrast, the seventh wave had the highest median age (79 years) and comorbidity (Charlson: 2.7), while only 3% of patients had bilateral pneumonia and 3% required intubation. The overall mortality rate was 10.3%. The first wave represented 39% of the total. The variables related to mortality were age (OR: 1.08, 1.07-1.09), cancer (OR: 1.99, 1.53-2.60), dementia (OR: 1.82, 1.20-2.75), the Charlson index (1.38, 1.31-1.47), the need for high-flow oxygen (OR: 6.10, 4.94-7.52), mechanical ventilation (OR: 11.554, 6.996-19.080), and CRP (OR: 1.04, 1.03-1.06). (4) Conclusions: The variables associated with mortality included age, comorbidity, respiratory failure, and inflammation. Differences in the baseline characteristics of admitted patients explained the differences in mortality in each wave. Differences observed between patients admitted in the latest wave and the earlier ones suggest that COVID-19 has evolved into a distinct disease, requiring a distinct approach.


Assuntos
COVID-19 , Epidemias , Humanos , Idoso , COVID-19/epidemiologia , Estudos Retrospectivos , Hospitais , Hospitalização
4.
Toxins (Basel) ; 15(8)2023 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-37624255

RESUMO

Centruroides possanii is a recently discovered species of "striped scorpion" found in Mexico. Certain species of Centruroides are known to be toxic to mammals, leading to numerous cases of human intoxications in the country. Venom components are thought to possess therapeutic potential and/or biotechnological applications. Hence, obtaining and analyzing the secretory gland transcriptome and venom proteome of C. possanii is relevant, and that is what is described in this communication. Since this is a newly described species, first, its LD50 to mice was determined and estimated to be 659 ng/g mouse weight. Using RNA extracted from this species and preparing their corresponding cDNA fragments, a transcriptome analysis was obtained on a Genome Analyzer (Illumina) using the 76-base pair-end sequencing protocol. Via high-throughput sequencing, 19,158,736 reads were obtained and ensembled in 835,204 sequences. Of them, 28,399 transcripts were annotated with Pfam. A total of 244 complete transcripts were identified in the transcriptome of C. possanii. Of these, 109 sequences showed identity to toxins that act on ion channels, 47 enzymes, 17 protease inhibitors (PINs), 11 defense peptides (HDPs), and 60 in other components. In addition, a sample of the soluble venom obtained from this scorpion was analyzed using an Orbitrap Velos apparatus, which allowed for identification by liquid chromatography followed by mass spectrometry (LC-MS/MS) of 70 peptides and proteins: 23 toxins, 27 enzymes, 6 PINs, 3 HDPs, and 11 other components. Until now, this work has the highest number of scorpion venom components identified through omics technologies. The main novel findings described here were analyzed in comparison with the known data from the literature, and this process permitted some new insights in this field.


Assuntos
Escorpiões , Peçonhas , Humanos , Animais , Camundongos , Escorpiões/genética , Cromatografia Líquida , Espectrometria de Massas em Tandem , Inibidores de Proteases , Mamíferos
5.
Toxicon ; 233: 107232, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37536653

RESUMO

Scorpions are a group of arthropods that strike fear in many people due to their severe medical symptoms, even death, caused by their venomous stings. Even so, not all scorpion species contain harmful venoms against humans but still have valuable bioactive molecules, which could be used in developing new pharmaceutical leads for treating important diseases. This work conducted a comprehensive analysis of the venom from the scorpion Thorellius intrepidus. The venom of T. intrepidus was separated by size exclusion chromatography, and four main fractions were obtained. Fraction IV (FIV) contained small molecules representing over 90% of the total absorbance at 280 nm. Analysis of fraction FIV by RP-HPLC indicated the presence of three main molecules (FIV.1, FIV.2, and FIV.3) with similar UV absorbance spectra profiles. The molecular masses of FIV.1, FIV.2, and FIV.3 were determined, resulting in 175.99, 190.07, and 218.16 Da, respectively. Further confirmation through 1H-NMR and 13C-NMR analyses revealed that these molecules were serotonin, N-methylserotonin, and bufotenidine. These intriguing compounds are speculated to play a pivotal role in self-defense and increasing venom toxicity and could also offer promising biotechnological applications as small bioactive molecules.


Assuntos
Picadas de Escorpião , Venenos de Escorpião , Animais , Humanos , Escorpiões , Peçonhas , Venenos de Escorpião/química
6.
Nat Ecol Evol ; 7(7): 1002-1011, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37169879

RESUMO

Soils support an immense portion of Earth's biodiversity and maintain multiple ecosystem functions which are essential for human well-being. Environmental thresholds are known to govern global vegetation patterns, but it is still unknown whether they can be used to predict the distribution of soil organisms and functions across global biomes. Using a global field survey of 383 sites across contrasting climatic and vegetation conditions, here we showed that soil biodiversity and functions exhibited pervasive nonlinear patterns worldwide and are mainly governed by water availability (precipitation and potential evapotranspiration). Changes in water availability resulted in drastic shifts in soil biodiversity (bacteria, fungi, protists and invertebrates) and soil functions including plant-microbe interactions, plant productivity, soil biogeochemical cycles and soil carbon sequestration. Our findings highlight that crossing specific water availability thresholds can have critical consequences for the provision of essential ecosystem services needed to sustain our planet.


Assuntos
Ecossistema , Solo , Animais , Humanos , Solo/química , Água , Biodiversidade , Invertebrados
7.
Toxins (Basel) ; 15(2)2023 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-36828459

RESUMO

Skin secretions of toads are a complex mixture of molecules. The substances secreted comprise more than 80 different compounds that show diverse pharmacological activities. The compounds secreted through skin pores and parotid glands are of particular interest because they help toads to endure in habitats full of pathogenic microbes, i.e., bacteria, fungi, viruses, and protozoa, due to their content of components such as bufadienolides, alkaloids, and antimicrobial peptides. We carried out an extensive literature review of relevant articles published until November 2022 in ACS Publications, Google Scholar, PubMed, and ScienceDirect. It was centered on research addressing the biological characterization of the compounds identified in the species of genera Atelopus, Bufo, Duttaphrynus, Melanophryniscus, Peltopryne, Phrynoidis, Rhaebo, and Rhinella, with antibacterial, antifungal, antiviral, and antiparasitic activities; as well as studies performed with analogous compounds and skin secretions of toads that also showed these activities. This review shows that the compounds in the secretions of toads could be candidates for new drugs to treat infectious diseases or be used to develop new molecules with better properties from existing ones. Some compounds in this review showed activity against microorganisms of medical interest such as Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Coronavirus varieties, HIV, Trypanosoma cruzi, Leishmania chagasi, Plasmodium falciparum, and against different kinds of fungi that affect plants of economic interest.


Assuntos
Anti-Infecciosos , Bufanolídeos , Animais , Bufonidae , Antibacterianos , Bufanolídeos/farmacologia , Antifúngicos , Pele
8.
Microbiome ; 10(1): 219, 2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36503688

RESUMO

BACKGROUND: Little is known about the global distribution and environmental drivers of key microbial functional traits such as antibiotic resistance genes (ARGs). Soils are one of Earth's largest reservoirs of ARGs, which are integral for soil microbial competition, and have potential implications for plant and human health. Yet, their diversity and global patterns remain poorly described. Here, we analyzed 285 ARGs in soils from 1012 sites across all continents and created the first global atlas with the distributions of topsoil ARGs. RESULTS: We show that ARGs peaked in high latitude cold and boreal forests. Climatic seasonality and mobile genetic elements, associated with the transmission of antibiotic resistance, were also key drivers of their global distribution. Dominant ARGs were mainly related to multidrug resistance genes and efflux pump machineries. We further pinpointed the global hotspots of the diversity and proportions of soil ARGs. CONCLUSIONS: Together, our work provides the foundation for a better understanding of the ecology and global distribution of the environmental soil antibiotic resistome. Video Abstract.


Assuntos
Antibacterianos , Solo , Humanos , Antibacterianos/farmacologia , Ecologia , Fenótipo
9.
J Ecol ; 110(9): 2074-2087, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36250131

RESUMO

Ongoing global warming and alterations in rainfall patterns driven by climate change are known to have large impacts on biogeochemical cycles, particularly on drylands. In addition, the global increase in atmospheric nitrogen (N) deposition can destabilize primary productivity in terrestrial ecosystems, and phosphorus (P) may become the most limiting nutrient in many terrestrial ecosystems. However, the impacts of climate change on soil P pools in drylands remain poorly understood. Furthermore, it is unknown whether biocrusts, a major biotic component of drylands worldwide, modulate such impacts.Here we used two long-term (8-10 years) experiments conducted in Central (Aranjuez) and SE (Sorbas) Spain to test how a ~2.5°C warming, a ~30% rainfall reduction and biocrust cover affected topsoil (0-1 cm) P pools (non-occluded P, organic P, calcium bound P, occluded P and total P).Warming significantly increased most P pools-except occluded P-in Aranjuez, whereas only augmented non-occluded P in Sorbas. The rainfall reduction treatment had no effect on the soil P pools at any experimental site. Biocrusts increased most soil P pools and conferred resistance to simulated warming for major P pools at both sites, and to rainfall reduction for non-occluded and occluded P in Aranjuez. Synthesis. Our findings provide novel insights on the responses of soil P pools to warming and rainfall reduction, and highlight the importance of biocrusts as modulators of these responses in dryland ecosystems. Our results suggest that the observed negative impacts of warming on dryland biocrust communities will decrease their capacity to buffer changes in topsoil P driven by climate change.


Tanto el calentamiento global en curso como las alteraciones en los patrones de precipitaciones provocados por el cambio climático tienen grandes impactos en los ciclos biogeoquímicos, particularmente en los ecosistemas áridos y semiáridos. Además, el aumento global de la deposición de nitrógeno (N) atmosférico puede desestabilizar la productividad primaria en los ecosistemas terrestres, y el fósforo (P) puede convertirse en el nutriente más limitante en muchos de estos ecosistemas. Sin embargo, los impactos del cambio climático en las reservas de P del suelo en los ecosistemas áridos y semiáridos siguen sin comprenderse totalmente. Además, se desconoce si la costra biológica del suelo, un componente biótico importante de los ecosistemas áridos y semiáridos en todo el mundo, modulan tales impactos.Utilizamos dos experimentos a largo plazo (8­10 años) ubicados en el centro (Aranjuez) y el sureste (Sorbas) de España para probar cómo el calentamiento de ~2,5°C, la reducción de las precipitaciones de ~30 % y la cobertura de costra biológica afectaron los pools de P (P no ocluido, P orgánico, P ligado al calcio, P ocluido y P total) de la capa superior del suelo (0­1 cm).El calentamiento aumentó significativamente la mayoría de los pools de P ­excepto el P ocluido­ en Aranjuez, mientras que solo aumentó el P no ocluido en Sorbas. El tratamiento de reducción de las precipitaciones no tuvo efecto en los pools de P del suelo en ningún sitio experimental. La costra biológica aumentó la mayoría de los depósitos de P del suelo y confirieron resistencia al calentamiento simulado para los principales pools de P en ambos sitios, y a la reducción de las precipitaciones para el P no ocluido y ocluido en Aranjuez. Síntesis. Nuestros hallazgos brindan información novedosa sobre las respuestas de los pools de P del suelo al calentamiento y la reducción de las precipitaciones, y resaltan la importancia de la costra biológica como moduladora de estas respuestas en los ecosistemas áridos y semiáridos. Nuestros resultados sugieren que los impactos negativos observados del calentamiento en las comunidades de costra biológica de los ecosistemas áridos y semiáridos disminuirán su capacidad para amortiguar los cambios en el P del suelo provocados por el cambio climático.

10.
Toxicon ; 197: 114-125, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33901550

RESUMO

The peptide, denominated Ct1a, is a ß-toxin of 66 amino acids, isolated from venom of the scorpion, Centruroides tecomanus, collected in Colima, Mexico. This toxin was purified using size exclusion, cationic exchange, and reverse phase chromatography. It is the most abundant toxin, representing 1.7% of the soluble venom. Its molecular mass of 7588.9 Da was determined by mass spectrometry. The amino acid sequence was determined by Edman degradation and confirmed by transcriptomic analysis. Since neurons of the suprachiasmatic nucleus (SCN) maintain a spontaneous firing rate (SFR), we evaluated the physiological effects of toxin Ct1a on these neurons. The SFR exhibited a bimodal concentration-dependent response: 100 nM of Ct1a increased the SFR by 223%, whereas 500 nM and 1000 nM reduced it to 42% and 7%, respectively. Control experiments, consisting of recordings of the SFR during a time similar to that used in Ct1a testing, showed stability throughout the trials. Experiments carried out with denatured Ct1a toxin (500 nM) caused no variation in SFR recordings. Action potentials of SCN neurons, before and after Ct1a (100 nM) showed changes in the time constants of depolarization and repolarization phases, amplitude, and half-time. Finally, recordings of hNav1.6 sodium currents indicated that Ct1a shifts the channel activation to a more negative potential and reduces the amplitude of the peak current. These results all demonstrate that toxin Ct1a affects the SFR of SCN neurons by acting upon sodium channels of sub-type 1.6, implicating them in regulation of the SFR of SCN neurons.


Assuntos
Venenos de Escorpião , Escorpiões , Animais , México , Neurônios , Núcleo Supraquiasmático , Peçonhas
11.
Hosp Pharm ; 55(5): 338-341, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32999504

RESUMO

Purpose: To report a case of posterior reversible encephalopathy syndrome (PRES) in a 75 year-old patient who was taking concomitant ciprofloxacin and metronidazole. Method: Case report Results: A patient had been prescribed ciprofloxacin and metronidazole during a recent hospitalization and continued this regimen outpatient. Two weeks after discharge and 3 weeks after initiation of her regimen, she was brought to the emergency department after developing acute weakness and lightheadedness. After admission, the patient declined more rapidly and began seizing with subsequent intubation. Initial computed tomographic (CT) imaging showed no acute neurological abnormalities, and a sepsis workup was initiated. After negative CT, a magnetic resonance imaging scan was performed that showed a T2 flair and hyperdensity consistent with PRES. The final diagnosis was considered to be PRES secondary to ciprofloxacin/metronidazole utilization. Conclusion: Antibiotic induced PRES is a condition that needs to be explored more thoroughly.

12.
Nat Commun ; 11(1): 4721, 2020 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-32948775

RESUMO

The importance of soil age as an ecosystem driver across biomes remains largely unresolved. By combining a cross-biome global field survey, including data for 32 soil, plant, and microbial properties in 16 soil chronosequences, with a global meta-analysis, we show that soil age is a significant ecosystem driver, but only accounts for a relatively small proportion of the cross-biome variation in multiple ecosystem properties. Parent material, climate, vegetation and topography predict, collectively, 24 times more variation in ecosystem properties than soil age alone. Soil age is an important local-scale ecosystem driver; however, environmental context, rather than soil age, determines the rates and trajectories of ecosystem development in structure and function across biomes. Our work provides insights into the natural history of terrestrial ecosystems. We propose that, regardless of soil age, changes in the environmental context, such as those associated with global climatic and land-use changes, will have important long-term impacts on the structure and function of terrestrial ecosystems across biomes.


Assuntos
Biota , Ecossistema , Solo/química , Bactérias/classificação , Biodiversidade , Biomassa , Clima , Fungos/classificação , Microbiota , Plantas/classificação , Fatores de Tempo
13.
Cell Signal ; 73: 109673, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32470518

RESUMO

Activation process of mature B cell is predominantly driven by specific BCR-mediated pathways, switched on and off all through late B cell differentiation stages. Mice deficient for APS, a member of the Lnk/SH2B family of adaptor proteins, showed that this adaptor plays a BCR-mediated regulatory role in mature B cells. However, the intermediates involved in this adaptor modulating functions in B cells are still unknown. In the present study, we investigated the role of APS in regulating BCR signalling notably through cytoskeleton remodeling in mature B cells. Herein, we showed that APS function is stage specific, as it exclusively intervenes in mature B cells. Upon activation, APS colocalizes with the BCR and associates with important regulators of BCR signalling, such as Syk and Cbl kinase. Importantly, APS interferes, as a scaffold protein, with the stability of Syk kinase by recruiting Cbl. This function is mainly mediated by APS SH2 domain, which regulates BCR-evoked cell dynamics. Our findings thus reveal that APS plays a regulatory role in BCR-induced responses by specifically modulating its interacting partners, which positions APS as a relevant modulator of BCR signalling in mature B cells.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Linfócitos B , Proteínas Proto-Oncogênicas c-bcr/metabolismo , Animais , Linfócitos B/citologia , Linfócitos B/metabolismo , Linhagem Celular , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais
14.
Toxicon ; 180: 62-78, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32283106

RESUMO

Lizards of the Helodermatidae (Anguimorpha) family consist of at least two well recognized species: Heloderma horridum horridum and Heloderma suspectum suspectum. They contain specialized glands in their jaws that produce venomous secretions that causes envenoming symptoms to bitten animals. One way to study proteins from such secretions is by RNA-seq; a powerful molecular tool to characterize the transcriptome of such specialized gland, and its protein secretions. The total RNA from venom gland tissues of H. horridum horridum was extracted and a cDNA library was constructed and sequenced. Overall, 114,172 transcripts were found, and 199 were annotated based on sequence similarities to previously described peptides/proteins. Transcripts coding for putative exendins, defensins, natriuretics and serine protease inhibitors were the most highly expressed. Transcripts that code for several putative serine proteases, phospholipases, metalloproteases, lipases, L-amino oxidase and nucleases were also found. Some of the novel identified transcripts were translationally controlled tumor proteins, venom factors, vespryns, waprins, lectins, cystatins and serine protease inhibitors. All these new protein structures may contribute to a better understanding of the venomous secretions of the Helodermatidae family.


Assuntos
Lagartos/genética , Peçonhas , Sequência de Aminoácidos , Animais , Sequência de Bases , Sequenciamento de Nucleotídeos em Larga Escala , Lagartos/metabolismo , Peptídeos , Fosfolipases , Transcriptoma
15.
Toxicon ; 179: 21-32, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32126222

RESUMO

Centruroides hirsutipalpus (Scorpiones: Buthidae) is related to the "striped scorpion" group inhabiting the western Pacific region of Mexico. Human accidents caused by this species are medically important due to the great number of people stung and the severity of the resulting intoxication. This communication reports an extensive venom characterization using high-throughput proteomic and Illumina transcriptomic sequencing performed with RNA purified from its venom glands. 2,553,529 reads were assembled into 44,579 transcripts. From these transcripts, 23,880 were successfully annoted using Trinotate. Using specialized databases and by performing bioinformatic searches, it was possible to identify 147 putative venom protein transcripts. These include α- and ß-type sodium channel toxins (NaScTx), potassium channel toxins (KScTx) (α-, ß-, δ-, γ- and λ-types), enzymes (metalloproteases, hyaluronidases, phospholipases, serine proteases, and monooxygenases), protease inhibitors, host defense peptides (HDPs) such as defensins, non-disulfide bridge peptides (NDBPs), anionic peptides, superfamily CAP proteins, insulin growth factor-binding proteins (IGFBPs), orphan peptides, and other venom components (La1 peptides). De novo tandem mass spectrometric sequencing of digested venom identificatied 50 peptides. The venom of C. hirsutipalpus contains the highest reported number (77) of transcripts encoding NaScTxs, which are the components responsible for human fatalities.


Assuntos
Venenos de Escorpião/química , Escorpiões , Animais , Proteínas de Artrópodes/metabolismo , Glândulas Exócrinas , Sequenciamento de Nucleotídeos em Larga Escala , México , Proteoma/metabolismo , Proteômica , Venenos de Escorpião/metabolismo , Transcriptoma/fisiologia
16.
Nat Ecol Evol ; 4(2): 210-220, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32015427

RESUMO

The role of soil biodiversity in regulating multiple ecosystem functions is poorly understood, limiting our ability to predict how soil biodiversity loss might affect human wellbeing and ecosystem sustainability. Here, combining a global observational study with an experimental microcosm study, we provide evidence that soil biodiversity (bacteria, fungi, protists and invertebrates) is significantly and positively associated with multiple ecosystem functions. These functions include nutrient cycling, decomposition, plant production, and reduced potential for pathogenicity and belowground biological warfare. Our findings also reveal the context dependency of such relationships and the importance of the connectedness, biodiversity and nature of the globally distributed dominant phylotypes within the soil network in maintaining multiple functions. Moreover, our results suggest that the positive association between plant diversity and multifunctionality across biomes is indirectly driven by soil biodiversity. Together, our results provide insights into the importance of soil biodiversity for maintaining soil functionality locally and across biomes, as well as providing strong support for the inclusion of soil biodiversity in conservation and management programmes.


Assuntos
Ecossistema , Solo , Biodiversidade , Fungos , Humanos , Microbiologia do Solo
17.
Mol Ecol ; 29(4): 752-761, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31697860

RESUMO

Unlike plants and vertebrates, the ecological preferences, and potential vulnerabilities of soil invertebrates to environmental change, remain poorly understood in terrestrial ecosystems globally. We conducted a cross-biome survey including 83 locations across six continents to advance our understanding of the ecological preferences and vulnerabilities of the diversity of dominant and functionally important soil invertebrate taxa, including nematodes, arachnids and rotifers. The diversity of invertebrates was analyzed through amplicon sequencing. Vegetation and climate drove the diversity and dominant taxa of soil invertebrates. Our results suggest that declines in forest cover and plant diversity, and reductions in plant production associated with increases in aridity, can result in reductions of the diversity of soil invertebrates in a drier and more managed world. We further developed global atlases of the diversity of these important soil invertebrates, which were cross-validated using an independent database. Our study advances the current knowledge of the ecological preferences and vulnerabilities of the diversity and presence of functionally important soil invertebrates in soils from across the globe. This information is fundamental for improving and prioritizing conservation efforts of soil genetic resources and management policies.


Assuntos
Aracnídeos/genética , Invertebrados/genética , Nematoides/genética , Rotíferos/genética , Animais , Ecossistema , Florestas , Solo
18.
C R Biol ; 342(9-10): 331-344, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31680022

RESUMO

As part of an ongoing survey of scorpion diversity in Colima, Mexico, the isolated mountain Cerro Grande, part of the Biosphere Reserve Sierra de Manantlán, was investigated. Centruroides possanii sp. nov., the fifth species of the genus from the state, was discovered during fieldwork in the massif and is described in the present paper. Physiographical and climatic features of Cerro Grande may restrict the range of this new species; thus, we hypothesized that it may be a microendemic species that requires priority conservation. The new species is not assigned to any Centruroides species group recognized because some of its morphological features do not fit the current diagnosis of any of these groups, and these different groups are non-monophyletic and consequently ill-diagnosed. The new species is profusely illustrated, particularly the hemispermatophore. A distribution map is presented along with the other two more common species distributed in Colima. Because only indirect data on the potency of its venom is available, the medical importance of this new species described here is yet to be known.


Assuntos
Escorpiões/classificação , Animais , México , Escorpiões/anatomia & histologia
19.
Nat Commun ; 10(1): 3481, 2019 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-31375717

RESUMO

Identifying the global drivers of soil priming is essential to understanding C cycling in terrestrial ecosystems. We conducted a survey of soils across 86 globally-distributed locations, spanning a wide range of climates, biotic communities, and soil conditions, and evaluated the apparent soil priming effect using 13C-glucose labeling. Here we show that the magnitude of the positive apparent priming effect (increase in CO2 release through accelerated microbial biomass turnover) was negatively associated with SOC content and microbial respiration rates. Our statistical modeling suggests that apparent priming effects tend to be negative in more mesic sites associated with higher SOC contents. In contrast, a single-input of labile C causes positive apparent priming effects in more arid locations with low SOC contents. Our results provide solid evidence that SOC content plays a critical role in regulating apparent priming effects, with important implications for the improvement of C cycling models under global change scenarios.

20.
Proc Natl Acad Sci U S A ; 116(14): 6891-6896, 2019 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-30877251

RESUMO

Belowground organisms play critical roles in maintaining multiple ecosystem processes, including plant productivity, decomposition, and nutrient cycling. Despite their importance, however, we have a limited understanding of how and why belowground biodiversity (bacteria, fungi, protists, and invertebrates) may change as soils develop over centuries to millennia (pedogenesis). Moreover, it is unclear whether belowground biodiversity changes during pedogenesis are similar to the patterns observed for aboveground plant diversity. Here we evaluated the roles of resource availability, nutrient stoichiometry, and soil abiotic factors in driving belowground biodiversity across 16 soil chronosequences (from centuries to millennia) spanning a wide range of globally distributed ecosystem types. Changes in belowground biodiversity during pedogenesis followed two main patterns. In lower-productivity ecosystems (i.e., drier and colder), increases in belowground biodiversity tracked increases in plant cover. In more productive ecosystems (i.e., wetter and warmer), increased acidification during pedogenesis was associated with declines in belowground biodiversity. Changes in the diversity of bacteria, fungi, protists, and invertebrates with pedogenesis were strongly and positively correlated worldwide, highlighting that belowground biodiversity shares similar ecological drivers as soils and ecosystems develop. In general, temporal changes in aboveground plant diversity and belowground biodiversity were not correlated, challenging the common perception that belowground biodiversity should follow similar patterns to those of plant diversity during ecosystem development. Taken together, our findings provide evidence that ecological patterns in belowground biodiversity are predictable across major globally distributed ecosystem types and suggest that shifts in plant cover and soil acidification during ecosystem development are associated with changes in belowground biodiversity over centuries to millennia.


Assuntos
Biodiversidade , Modelos Biológicos
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