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1.
Molecules ; 29(10)2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38792035

RESUMO

The crystal structure of 4-methylcatechol (4MEC) has, to date, never been solved, despite its very simple chemical formula C7O2H8 and the many possible applications envisaged for this molecule. In this work, this gap is filled and the structure of 4MEC is obtained by combining X-ray powder diffraction and first principle calculations to carefully locate hydrogen atoms. Two molecules are present in the asymmetric unit. Hirshfeld analysis confirmed the reliability of the solved structure, since the two molecules show rather different environments and H-bond interactions of different directionality and strength. The packing is characterised by a peculiar hydrogen bond network with hydroxyl nests formed by two adjacent octagonal frameworks. It is noteworthy that the observed short contacts suggest strong inter-molecular interactions, further confirmed by strong inter-crystalline aggregation observed by microscopic images, indicating the growth, in many crystallization attempts, of single aggregates taller than half a centimetre and, often, with spherical shapes. These peculiarities are induced by the presence of methyl group in 4MEC, since the parent compound catechol, despite its chemical similarity, shows a standard layered packing alternating hydrophobic and polar layers. Finally, the complexity and peculiarity of the packing and crystal growth features explain why a single crystal could not be obtained for a standard structural analysis.

2.
J Xenobiot ; 14(2): 484-496, 2024 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-38651379

RESUMO

Graphene-based nanomaterials are exceptionally attractive for a wide range of applications, raising the likelihood of the release of graphene-containing nanoparticles into aquatic environments. The growing use of these carbon nanomaterials in different industries highlights the crucial need to investigate their environmental impact and evaluate potential risks to living organisms. The current investigation evaluated the nanotoxicity of graphene (nanoflakes) and graphene oxide (GO) nanoparticles on the cardiorespiratory responses (heart rate, gill ventilation frequency), as well as the swimming and nesting behavioral parameters of early stage larvae and juvenile salmonids. Both short-term (96 h) and long-term (23 days) exposure experiments were conducted using two common species: brown trout (Salmo trutta) and rainbow trout (Oncorhynchus mykiss). The findings demonstrated notable alterations in fish nesting behavior, swimming performance, and cardiorespiratory functions, indicating the potential toxicity of nanoparticles. This impact was observed at both physiological and whole-organismal levels in salmonids at early stages. Future investigations should explore different types of nanocarbons and their potential enduring effects on fish population structure, considering not only individual survival but also broader aspects of development, including feeding, reproductive, and other social dynamics.

3.
Lasers Surg Med ; 56(4): 361-370, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38506244

RESUMO

BACKGROUND: Limited research exists on laser treatment of giant congenital melanocytic nevus (GCMN). OBJECTIVE: We sought to elucidate the efficacy of the Erbium: YAG laser on GCMN and the histologic factors associated with a positive clinical response. METHODS AND MATERIALS: Between 2019 and 2022, we enrolled 30 medium-to-giant CMN patients who underwent Er: YAG laser treatment. All patients received biopsies before and after laser treatments. Clinical efficacy outcomes were evaluated by the investigator's global assessment (IGA), 5-point scale of depigmentation, and Vancouver Scar Scale (VSS) scores at least 6 months after treatment. RESULTS: Of the 30 cases, 18 (60.0%) showed improvement (IGA score ≥3). Eight (26.7%) patients showed repigmentation. Eight (26.7%) patients developed hypertrophic scars. The average IGA, depigmentation, and VSS scores were 2.93, 3.57, and 3.20. The IGA score was higher (3.24 ± 1.18 vs. 2.22 ± 0.97, p = 0.031) and a lower repigmentation rate (14.3% vs. 55.6%, p = 0.032) was observed in the cases with Grenz zone. The IGA score was higher (3.33 ± 1.24 vs. 2.13 ± 0.89, p = 0.023) and the repigmentation rate was lower (11.1% vs. 50.0%, p = 0.034) also in the cases with the melanocytes nests with aggregation of melanin. Lesions with superficial ablation resulted in less hypertrophic scar formation than those with deep ablation (5.9% vs. 53.8%, p < 0.05). CONCLUSION: The Er: YAG laser demonstrated effective clinical results for GCMNs. The grenz zone and the melanocytes nests with aggregation of melanin are promising predictors of laser efficacy.


Assuntos
Cicatriz Hipertrófica , Terapia a Laser , Lasers de Estado Sólido , Nevo Pigmentado , Neoplasias Cutâneas , Humanos , Érbio , Melaninas , Lasers de Estado Sólido/uso terapêutico , Terapia a Laser/métodos , Resultado do Tratamento , Nevo Pigmentado/radioterapia , Nevo Pigmentado/cirurgia , Cicatriz Hipertrófica/patologia , Imunoglobulina A
4.
J Anim Ecol ; 93(6): 691-704, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38525599

RESUMO

As humans increasingly modify the natural world, many animals have responded by changing their behaviour. Understanding and predicting the extent of these responses is a key step in conserving these species. For example, the tendency for some species of birds to incorporate anthropogenic items-particularly plastic material-into their nests is of increasing concern, as in some cases, this behaviour has harmful effects on adults, young and eggs. Studies of this phenomenon, however, have to date been largely limited in geographic and taxonomic scope. To investigate the global correlates of anthropogenic (including plastic) nest material use, we used Bayesian phylogenetic mixed models and a data set of recorded nest materials in 6147 species of birds. We find that, after controlling for research effort and proximity to human landscape modifications, anthropogenic nest material use is correlated with synanthropic (artificial) nesting locations, breeding environment and the number of different nest materials the species has been recorded to use. We also demonstrate that body mass, range size, conservation status and brain size do not explain variation in the recorded use of anthropogenic nest materials. These results indicate that anthropogenic materials are more likely to be included in nests when they are more readily available, as well as potentially by species that are more flexible in their nest material choice.


Assuntos
Teorema de Bayes , Aves , Comportamento de Nidação , Animais , Aves/fisiologia , Efeitos Antropogênicos , Filogenia , Plásticos , Conservação dos Recursos Naturais
5.
Ecol Evol ; 14(3): e11175, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38505186

RESUMO

White-rumped vultures (Gyps bengalensis) are critically endangered species, and protecting their habitats, particularly the nesting trees, may have a positive impact on their reproductive success. For a better understanding of vultures' habitat needs, the characteristics of nesting trees should be accounted. In this paper, we compare the characteristics of the trees that have vultures' nests and that do not by randomly select a control tree within a 10 m radius of the nesting tree. We extensively searched and monitored the white-rumped vultures' nests, nesting trees, and nesting tree species in Nepal between 2002 and 2022, and measured the characteristics of sampled trees such as their height, girth, canopy spread, branching orders, and whorls. We recorded 1161 nests of white-rumped vulture in total on 194 trees belonging to 19 species over the past two decades. White-rumped vultures preferred the kapok trees (Bombax ceiba) for nest construction than other tree species (χ 2 = 115.38, df = 1, p < .001) as 66.49% of nests were built on them. In the logistic regression model, the number of whorls on a tree, canopy spread, and the height of the first branch determined whether a nest was present or absent on a tree. These results help to prioritize the tree attributes in a habitat conservation plan for vultures.

6.
Cytotechnology ; 76(1): 123-137, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38304627

RESUMO

The antiviral properties of the extracts of Vespa crabro nests collected from the Black Sea, Turkey have been investigated on Spodoptera frugiperda (Sf) cell cultures of Autographa californica multicapsid nuclear polyhedrosis virus (AcMNPV). The effect of nests on cell viability and cytotoxicity analysis and the antiviral assay was studied, and the cytopathic effects of the virus were detected. The nest's viral content was identified. The impact of nest extracts on the protein synthesis of the virus was investigated. Also interaction with pUC18 plasmid DNA was investigated, to analyse the protective effects of the Vespa crabro nest extract againist to hydroxyl radical-mediated DNA damage. 50 µg/ml concentration of ethanol, acetone, and petroleum ether extracts of the nests reduced the cytopathic effects of baculovirus on Sf cells. The extracts delayed infection above 25 µg/ml concentration. When the effects of nest extracts on virus titer were evaluated; the 50 µg/ml concentration of the acetone extract of the nest showed the highest effect (75%) reducing the virus titer. 25 µg/ml concentration of the ethanol extract of the nest showed the lowest effect (33.33%) with a reduction. The presence of polyhedrin protein was observed at 25 µg/ml concentrations of acetone and petroleum ether extracts. When the potential of the nest extracts to repair DNA damage, the nest extracts were found to have a concentration-dependent repair feature in different applications. As a result of bioactive component analysis, (Z) 9-Tricosane and (cis)-2-nonadecene (1.65%) were found to have the highest % areas. In other respects, 1H-Purine-6-amine, 2-dodecanol and hexadecanoic acid compaunds were Additionally, 1H-Purine-6-amine, 2-dodecanol and hexadecanoic acid compounds, which are associated with antiviral activity, also determined in the biocomponent analysis. Supplementary Information: The online version contains supplementary material available at 10.1007/s10616-023-00603-0.

8.
Life (Basel) ; 14(1)2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38255754

RESUMO

A 50-year-old male presented to the emergency room after experiencing sudden right upper limb facial numbness and dysphasia, followed by full recovery. A brain CT scan showed hyperdense lesions within the left hemispheric sulcus, which raised suspicion of spontaneous subarachnoid hemorrhage. A T1-weighted MRI showed multiple tiny leptomeningeal enhancements in the same area, and a digital subtraction angiography showed no signs of vascular abnormality. Cerebrospinal fluid cytology revealed atypical melanin-containing cells with minimal pleomorphism. One month later, the patient developed sixth nerve palsy, which was determined to be due to intracranial hypertension. Multiple giant nevi on the legs, trunk, and scalp were also observed. A skin biopsy showed well-defined and symmetrical proliferation of melanocytic nevus cell nests in the dermis. An open biopsy was performed due to the suspicious leptomeningeal lesions, which surprisingly revealed diffuse and thick black-colored tissue infiltration of the leptomeninges. Pathology confirmed the diagnosis of meningeal melanocytosis. A ventriculoperitoneal shunt was then placed, and the patient's neurological symptoms gradually improved. Based on the presence of multiple giant nevi on the patient's skin and the finding of diffuse meningeal melanocytosis during the open biopsy, the patient was diagnosed with neurocutaneous melanosis. The patient received 6 cycles triweekly of Ipilimumab and Nivolumab 8 months after initial diagnosis. Unfortunately, the disease progressed and the patient passed away 14 months after initial diagnosis.

9.
J Cutan Pathol ; 51(3): 184-192, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37967577

RESUMO

Melanotic cutaneous lupus erythematosus (LE) is a newly described clinical variant of chronic cutaneous LE, presenting with localized or diffuse brownish or grayish macular and reticulated pigmentation in the absence of erythema, scaling, atrophy, scarring, or telangiectasia. The diagnosis is based upon histopathology, which demonstrates the characteristic features of LE with an interface vacuolar dermatitis with melanophages, and a superficial and deep, perivascular and periadnexal lymphocytic infiltrate with mucin deposition. Herein, we describe a case of a 61-year-old White male presenting with melanotic cutaneous LE with a blaschkoid distribution on his face in which the histopathological phenomenon of "true melanocytic nests" in the setting of a lichenoid pattern was seen. We want to highlight how nests of cellular aggregates at the dermoepidermal junction labeling with melanocytic markers may occur in the setting of an interface tissue reaction. This benign reactional pattern may mimic atypical melanocytic proliferations, especially on sun-damaged skin. Clinicopathological correlation and careful microscopic examination using a panel of multiple melanocytic markers is crucial for making an accurate final diagnosis. All the cases of melanotic cutaneous LE reported in the literature are also reviewed.


Assuntos
Dermatite , Lúpus Eritematoso Cutâneo , Lúpus Eritematoso Discoide , Humanos , Masculino , Pessoa de Meia-Idade , Melanócitos/patologia , Lúpus Eritematoso Cutâneo/diagnóstico , Lúpus Eritematoso Cutâneo/patologia , Lúpus Eritematoso Discoide/patologia , Dermatite/patologia , Diagnóstico Diferencial
10.
Microbiol Mol Biol Rev ; 87(4): e0012121, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38047636

RESUMO

SUMMARYOver the past decade, hundreds of studies have characterized the microbial communities found in human-associated built environments (BEs). These have focused primarily on how the design and use of our built spaces have shaped human-microbe interactions and how the differential selection of certain taxa or genetic traits has influenced health outcomes. It is now known that the more removed humans are from the natural environment, the greater the risk for the development of autoimmune and allergic diseases, and that indoor spaces can be harsh, selective environments that can increase the emergence of antimicrobial-resistant and virulent phenotypes in surface-bound communities. However, despite the abundance of research that now points to the importance of BEs in determining human-microbe interactions, only a fraction of non-human animal structures have been comparatively explored. It is here, in the context of human-associated BE research, that we consider the microbial ecology of animal-built natural nests and burrows, as well as artificial enclosures, and point to areas of primary interest for future research.


Assuntos
Ambiente Construído , Microbiologia Ambiental , Animais , Humanos
11.
Animals (Basel) ; 13(22)2023 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-38003184

RESUMO

Bird and mammal nests and nest boxes constitute microenvironments in which various groups of invertebrates can live, including mites from the suborder Uropodina (Acari: Mesostigmata). The main aim of the current study was to ascertain the characteristics of mite communities from the suborder Uropodina, which inhabit the nests of dormice (Gliridae) built in nest boxes. The second aim of the study was to compare the habitat preferences of Leiodinychus orbicularis (C. L. Koch) and Apionoseius infirmus (Berlese), i.e., two typically nest-dwelling species of Uropodina. The material for the study was collected from nest boxes in six forest complexes in southwestern Poland. The conducted research revealed the presence of five species of Uropodina, with a total number of 559 specimens, in the examined boxes. Leiodinychus orbicularis was found in almost half of all of the examined boxes and was a superdominant species in the communities. The analysis of the habitat preferences of the two nest species of Uropodina showed that A. infirmus preferred old natural nests, in which the communities were formed from a larger number of species, without a significant statistical prevalence of one species. On the other hand, L. orbicularis occurred sporadically in open bird nests, but was very numerous and frequent in nest boxes. The significant dominance of L. orbicularis in nest boxes can probably be explained by the specific conditions prevailing in this type of microhabitat, including the very low humidity and food resources that this mite species prefers compared to other species of Uropodina.

12.
Animals (Basel) ; 13(20)2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37893913

RESUMO

The White Stork (Ciconia ciconia) and the Black Stork (Ciconia nigra) are well-known model organisms for the study of bird migration, as well as the selectivity of nesting sites and the choice of living environment. The former breeds mainly in open areas, while the latter inhabits forest areas. The acarofauna, and in particular Oribatida, inhabiting the nests of these species, has not been thoroughly explored so far. Therefore, we analyzed the material collected from 70 White Stork nests and 34 Black Stork nests in Poland, between Poznan and Rawicz, and in Kampinos National Park. Our research has increased the faunal and ecological knowledge of the mite fauna inhabiting the nests of large migratory bird species. Oribatida constituted 5-12% of the total mites identified in the nests of White and Black Storks. Their average number was several times higher in the Black Stork nests (80.2 individuals in 500 cm3). Also, the species diversity of moss mites was greater in the Black Stork nests (47 species). In total, the nests of the two stork species were inhabited by 62 moss mite species, with only 22 recorded in both the White and the Black Storks' nests. The most numerous species included Ramusella clavipectinata, R. fasciata, Oppiella subpectinata, Acrogalumna longipluma, and Scheloribates laevigatus. In addition, we found that juvenile oribatid mites accounted for 0.6% of all the mites in the White Stork nests, with tritonymphs having the largest share, while juveniles in the Black Stork nests comprised 1.4%, of which larvae and protonymphs had the largest share. Our research shows that the nests of large migratory birds provide living space for many mite species. In addition, we noted the potential importance of White and Black Stork nests for mite dispersion and the evolution of interspecies interactions.

13.
Dermatopathology (Basel) ; 10(3): 281-286, 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37754278

RESUMO

Lichen Planus Pigmentosus (LPP) is an uncommon variant of lichen planus characterized by the development of dark greyish-brown macules and patches primarily affecting sun-exposed areas. Histologically, it presents with lichenoid interface dermatitis with many melanophages. In select cases, the presence of melanocytic nests or pseudomelanocytic nests within LPP lesions has been documented, posing a diagnostic challenge. We present a detailed case report of a 32-year-old Eritrean woman with a longstanding history of hyperpigmented macules, alongside an in-depth review of the existing literature on lichenoid dermatoses featuring melanocytic or pseudomelanocytic nests. This paper delves into the clinical presentation, histopathological features, differential diagnosis, and potential mechanisms underlying this intriguing phenomenon.

14.
Front Psychol ; 14: 1175379, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37649685

RESUMO

Due to globalization, English has gradually become a lingua franca, leading to a rising demand for proficient English teachers all over the globe. In China, more EFL teachers are being recruited, particularly at the tertiary level, with a greater preference for so-called "native English speaking teachers (NESTs)" over "non-native English-speaking teachers (NNESTs)" due to the impacts of native-speakerism. Research has shown NESTs, NNESTs, and students are often misaligned in terms of beliefs about language learning and teaching which affect teaching effectiveness as well as student achievement. Recognizing this issue, this study investigated NESTs', NNESTs', and Chinese English-major students' perceptions of characteristics of effective EFL teachers at four mid-tier universities across China. Findings from semi-structured interviews with 16 students suggest that NNESTs and Chinese English-major students had similar views on language learning and teaching. Both groups valued prerequisite qualities such as having expert knowledge, language skills, teaching skills, and professionalism. NESTs, however, valued qualities such as caring, patience, flexibility, engagement, and awareness of students' learning needs. These differences are likely the result of these two groups of teachers' linguistic, cultural, and educational background differences. The highly uniform views of the two groups of teachers suggest that they tended to emphasize certain qualities while disregarding others. These findings suggest the need to raise teachers' and students' awareness of the benefits of different types of teacher qualities so that curriculum design and lesson planning can be implemented for better instructional alignment to ultimately improve teaching effectiveness.

15.
ACS Appl Mater Interfaces ; 15(34): 40478-40487, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37591494

RESUMO

Vapor-phase Beckmann rearrangement of cyclohexanone oxime (CHO) to ε-caprolactam (CPL) is still difficult to commercialize at the industrial scale due to its relatively low catalytic activity and poor lifetime. Herein, we synthesized a series of pure-silicon zeolites (including MFI, MEL, and -SVR) with three-dimensional 10-member-ring topolgies, diverse silanol status, and hierarchical porosity to investigate the synergistic effects of inner diffusivity and reactivity. S-1 zeolite of MFI-type topology with plentiful silanol nests exhibits a more preferable catalytic performance in terms of CHO conversion (99.7%) and CPL selectivity (89.7%), much higher than those of MEL- and -SVR-type zeolites mainly due to their diverse silanol distribution. With the construction of hierarchical porosity, S-1-P shows improved CPL selectivity of 94.1% owing to the enhanced diffusivity to shorten the retention time of the reactant and product molecules. The reaction mechanism and network have been further revealed by density functional theory (DFT) calculations and experimental designs, which indicate that silanol nests are major active sites due to their suitable interaction with CHO rather than terminal silanols. Particularly, the microenvironments of silanols can be modulated by alcohol solvents, ascribed to their different charge transfer and steric hindrance. Consequently, S-1-P shows superior CPL selectivity of 97.3% in ethonal solvents, which have higher adsorb energy of -0.627 eV with silanol nests than other alcohols. The present study not only provides a fundamental guide for the design of zeolite catalysts but also provides a reference for modulating the microenvironment of active sites according to the catalytic mechanism.

16.
Philos Trans R Soc Lond B Biol Sci ; 378(1884): 20220147, 2023 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-37427471

RESUMO

The evolution of behaviour can both influence, and be influenced by, morphology. Recent advances in methods and data availability have facilitated broad-scale investigations of physical form and behavioural function in many contexts, but the relationship between animal morphology and object manipulation-particularly objects used in construction-remains largely unknown. Here, we employ a new global database of nest materials used by 5924 species of birds together with phylogenetically informed random forest models to evaluate the link between beak shape and these nest-building materials. We find that beak morphology, together with species diet and access to materials, can predict nest-material use above chance and with high accuracy (68-97%). Much of this relationship, however, is driven by phylogenetic signal and sampling biases. We therefore conclude that while variation in nest material use is linked with that of beak shape across bird species, these correlations are modulated by the ecological context and evolutionary history of these species. This article is part of the theme issue 'The evolutionary ecology of nests: a cross-taxon approach'.


Assuntos
Bico , Aves , Animais , Filogenia , Bico/anatomia & histologia , Dieta , Comportamento de Nidação
17.
Philos Trans R Soc Lond B Biol Sci ; 378(1884): 20220156, 2023 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-37427475

RESUMO

Many bird species incorporate anthropogenic materials (e.g. sweet wrappers, cigarette butts and plastic strings) into their nests. Anthropogenic materials have become widely available as nesting materials in marine and terrestrial environments globally. These human-made objects can provide important benefits to birds such as serving as reliable signals to conspecifics or protecting against ectoparasites, but they can also incur fundamental survival and energetic costs via offspring entanglement and reduced insulative properties, respectively. From an ecological perspective, several hypotheses have been proposed to explain the use of anthropogenic nest materials (ANMs) by birds but no previous interspecific study has tried to identify the underlying mechanisms of this behaviour. In this study, we performed a systematic literature search and ran phylogenetically controlled comparative analyses to examine interspecific variation in the use of ANM and to examine the influence of several ecological and life-history traits. We found that sexual dimorphism and nest type significantly influenced the use of ANMs by birds providing support for the 'signalling hypothesis' that implies that ANMs reflect the quality of the nest builder. However, we found no support for the 'age' and 'new location' hypotheses, nor for a phylogenetic pattern in this behaviour, suggesting that it is widespread throughout birds. This article is part of the theme issue 'The evolutionary ecology of nests: a cross-taxon approach'.


Assuntos
Características de História de Vida , Comportamento de Nidação , Animais , Humanos , Filogenia , Aves
18.
Philos Trans R Soc Lond B Biol Sci ; 378(1884): 20220149, 2023 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-37427480

RESUMO

In the hyperarid Namib Desert, the sand termite Psammotermes allocerus Silvestri, 1908 (Isoptera: Rhinotermitidae) establishes colonies that create conspicuous, barren patches known as 'fairy circles' on permeable, sandy soils. The central bare areas of fairy circles serve the key function of storing moisture received from sparse rainfall. The sandy soil texture allows rapid infiltration and percolation of precipitation, while localized herbivory by the termites creates the bare patch, thereby reducing the rapid loss of soil moisture by the uptake and transpiration of water by plants. The resulting storage of rain water even during prolonged periods of drought enables perennial life in hyperarid desert environments and forms a globally unique example of ecosystem engineering by social insects. During the past decade, most publications primarily debated the origin of fairy circles. Here, we contribute to the special issue with a focus on the functional and evolutionary dimension of the structure of the Psammotermes colony with two differing nest types and two spatially separated key resources, as a successful adaptation to extreme desert environment. The paper is primarily a review and a synthesis of previous work, with the inclusion of new, relevant findings. This article is part of the theme issue 'The evolutionary ecology of nests: a cross-taxon approach'.


Assuntos
Ecossistema , Isópteros , Animais , Areia , Solo/química , Clima Desértico , Água
19.
FEMS Microbiol Ecol ; 99(8)2023 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-37481697

RESUMO

Truffle growers devote great efforts to improve black truffle productivity, developing agronomic practices such as 'truffle nests' (peat amendments that are supplemented with truffle spore inoculum). It has been hypothesized that improved fruiting associated with nests is linked to stimulation of truffle mycelia previously established in soil or to changes generated in soil fungal community. To assess this, we used real-time PCR to quantify black truffle extraradical mycelium during 2 years after nests installation. We also characterized the fungal community via high-throughput amplicon sequencing of the ITS region of rRNA genes. We found that neither the abundance of truffle mycelium in nests nor in the soil-nest interphase was higher than in the bulk soil, which indicates that nests do not improve mycelial growth. The fungal community in nests showed lower richness and Shannon index and was compositionally different from that of soil, which suggests that nests may act as an open niche for fungal colonization that facilitates truffle fruiting. The ectomycorrhizal fungal community showed lower richness in nests. However, no negative relationships between amount of truffle mycelium and reads of other ectomycorrhizal fungi were found, thus countering the hypothesis that ectomycorrhizal competition plays a role in the nest effect.


Assuntos
Ascomicetos , Micobioma , Micorrizas , Microbiologia do Solo , Ascomicetos/fisiologia , Solo
20.
Bot Stud ; 64(1): 21, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37458873

RESUMO

BACKGROUND: Xylaria collections from termite nests with dichotomously branched stromata have been identified as X. furcata. However, Léveillé's original material is no longer available, and the modern interpretation of X. furcata is based on a 1908 collection made by von Höhnel from termite nests at Buitenzorg Botanical Garden in Java. A packet of this von Höhnel material at FH was designated as the neotype by Rogers et al. in 2005. RESULTS: We reexamined the neotype from FH and its duplicates from various herbaria and found that three different species were mixed in these specimens. Despite that all of them have dichotomously branched stromata and tiny ascospores, only one fits the 2005 neotypification of X. furcata, where exposed perithecial mounds on the stromatal surface were unambiguously indicated. This portion of material is redesignated as the neotype, while the other two species with immersed perithecia are described as new: X. hoehnelii and X. robustifurcata. The ITS sequence obtained from the neotype helped us designate a specimen with cultures obtained from it as the epitype. From specimens identifiable as X. furcata, we describe four new species: X. brevifurcata, X. furcatula, X. insignifurcata, and X. tenellifurcata. Additionally, we recognize X. furcata var. hirsuta at the species level as X. hirsuta and consider X. scoparia a distinct species rather than a synonym of X. furcata. Molecular phylogenetic analyses based on three protein-coding loci showed that X. furcata and resembling species were grouped into two clusters: the X. furcata cluster with half-exposed to fully exposed perithecial mounds and the X. hoehnelii cluster with largely immersed perithecial mounds. CONCLUSION: Ten species are recognized for X. furcata and resembling species, all of which could have been identified as X. furcata in the past. Its diversity has been overlooked primarily due to the small and similar stromata. Several additional species have been confirmed to be related to X. furcata by DNA sequences but are yet to be described due to the lack of mature stromata. While the species diversity of macrotermitine termites is equally high in Africa as in Asia, all of the species are primarily found in Asia, with X. hirsuta as the only exception. This suggests that there may be many more undiscovered species for this fungal group.

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