Search

The numerous naturally-fragmented sky islands (SIs) in the Hengduan Mountains Region (HMR) of southwestern China constitute discontinuous landscapes where montane habitats are isolated by dry-hot valleys which have fostered exceptional species diversification and endemicity. However, studies documenting the crucial role of SI on the speciation dynamics of native freshwater organisms are scarce. Here we used a novel set of comprehensive genetic markers (24 nuclear DNA sequences and complete mitogenomes), morphological characters, and biogeographical information to reveal the evolutionary history and speciation mechanisms of a group of small-bodied montane potamids in the genus Tenuipotamon. Our results provide a robustly supported phylogeny, and suggest that the vicariance events of these montane crabs correlate well with the emergence of SIs due to the uplift of the HMR during the Late Oligocene. Furthermore, ancestrally, mountain ridges provided corridors for the dispersal of these montane crabs that led to the colonization of moist montane-specific habitats, aided by past climatic conditions that were the crucial determinants of their evolutionary history. The present results illustrated that the mechanisms isolating SIs are reinforced by the harsh-dry isolating climatic features of dry-hot valleys separating SIs and continue to affect local diversification. This offers insights into the causes of the high biodiversity and endemism shown by the freshwater crabs of the HMR-SIs in southwestern China., 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 © 2023 Elsevier Inc. All rights reserved.)

Xujiang School of acupuncture and moxibustion has a long history with distinctive academic characteristics and regional influence. Xujiang School, originated from Xi Hong in Song Dynasty, is the oldest acupuncture and moxibustion school recorded in Chinese history. Later, it was passed down from family to family for more than ten generations. The tenth generation Xi Xinqing passed it on to Chen Honggang and gradually evolved into a school of acupuncture and moxibustion with regional characteristics and a certain national influence. In terms of academic characteristics, doctors in Xujiang School kept innovating based on the Classics.Its acupuncture and moxibustion academic ideas including reinforcement and reduction , point selection and searching for the primary cause of disease in treatment have had an important impact on contemporary acupuncture in clinic.

The emergence and spread of azole resistance alleles in clinical and environmental isolates of Aspergillus fumigatus is a global human health concern and endangers the "One Health" approach in our fight against antifungal resistance (AFR) in this pathogen. A major challenge to combat AFR in A. fumigatus is the massive aerial dispersal ability of its asexual spores. Our recent fine-scale survey of greenhouse populations of A. fumigatus near Kunming, Yunnan, China, suggested that the use of azole fungicides for plant protection was likely a major driver of the high-frequency azole-resistant A. fumigatus (ARAF) in greenhouses. Here, we investigated the potential spread of those ARAF and the structure of geographic populations of A. fumigatus by analyzing 452 isolates from 19 geographic locations across Yunnan. We found lower frequencies of ARAF in these outdoor populations than those in greenhouses near Kunming, but there were abundant new alleles and new genotypes, including those associated with azole resistance, consistent with multiple independent origins of ARAF across Yunnan. Interestingly, among the four ecological niches, the sediments of a large lake near Kunming were found to have the highest frequency of ARAF (~ 43%). While most genetic variations were observed within the 19 local populations, statistically significant genetic differentiations were found between many subpopulations within Yunnan. Furthermore, similar to greenhouse populations, these outdoor populations of A. fumigatus in Yunnan were significantly different from those in other parts of the world. Our results call for increased attention to local and regional studies of this fungal pathogen to help develop targeted control strategies against ARAF., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Aspergillus fumigatus is the main cause of invasive aspergillosis (IA) with a high annual global incidence and mortality rate. Recent studies have indicated an increasing prevalence of azole-resistant A. fumigatus (ARAF) strains, with agricultural use of azole fungicides as a potential contributor. China has an extensive agricultural production system and uses a wide array of fungicides for crop production, including in modern growth facilities such as greenhouses. Soils in greenhouses are among the most intensively cultivated. However, little is known about the occurrence and distribution of ARAF in greenhouse soils. Here, we investigated genetic variation and triazole drug susceptibility in A. fumigatus from greenhouses around metropolitan Kunming in Yunnan, southwest China. Abundant allelic and genotypic variations were found among 233 A. fumigatus strains isolated from nine greenhouses in this region. Significantly, ∼80% of the strains were resistant to at least one medical triazole drug, with >30% showing cross-resistance to both itraconazole and voriconazole. Several previously reported mutations associated with triazole resistance in the triazole target gene cyp51A were also found in our strains, with a strong positive correlation between the frequency of mutations at the cyp51A promoter and that of voriconazole resistance. Phylogenetic analyses of cyp51A gene sequences showed evidence for multiple independent origins of azole-resistant genotypes of A. fumigatus in these greenhouses. Evidence for multiple origins of azole resistance and the widespread distributions of genetically very diverse triazole-resistant strains of A. fumigatus in greenhouses calls for significant attention from public health agencies. IMPORTANCE The origin and prevalence of azole-resistant Aspergillus fumigatus have been attracting increasing attention from biologists, clinicians, and public health agencies. Current evidence suggests agricultural fungicide use as a major cause. In southwest China, greenhouses are used to produce large amounts of fruits, flowers, and vegetables for consumers throughout China as well as those in other countries, primarily in southeast Asia. Here, we found a very high frequency (∼80%) of triazole-resistant A. fumigatus in our sample, the highest reported so far, with a significant proportion of these strains resistant to both tested agricultural fungicides and medical triazole drugs. In addition, we found novel allelic and genotypic diversities and evidence for multiple independent origins of azole-resistant genotypes of A. fumigatus in greenhouse populations in this region. Our study calls for a systematic evaluation of the effects of azole fungicide usage in greenhouses on human health., (Copyright © 2021 Zhou et al.)

Background: Dental caries is one of the most common chronic diseases observed in elderly patients. The development of preventive strategies for dental caries in elderly individuals is vital., Objective: The objective of the present study was to construct a generalized regression neural network (GRNN) prediction model for the risk assessment of dental caries among the geriatric residents of Liaoning, China., Methods: A stratified equal-capacity random sampling method was used to randomly select 1144 elderly (65-74 years) residents (gender ratio 1 : 1) of Liaoning, China. Data for the oral assessment, including caries characteristics, and questionnaire survey from each participant were collected. Multivariate logistic regression analysis was then performed to identify the independent predictors. GRNN was applied to establish a prediction model for dental caries. The accuracy of the unconditional logistic regression and the GRNN early warning model was compared., Results: A total of 1144 patients fulfilled the requirements and completed the questionnaires. The caries rate was 68.5%, and the main associated factors were toothache history, residence area, smoking, and drinking. We randomly divided the data for the 1144 participants into a training set (915 cases) and a test set (229 cases). The optimal smoothing factor was 0.7, and the area under the receiver operating characteristic curve for the GRNN model was 0.626 (95% confidence interval, 0.544 to 0.708), with a P value of 0.002. In terms of consistency, sensitivity, and specificity, the GRNN model was better than the traditional unconditional multivariate logistic regression model., Conclusion: Geriatric (65-74 years) residents of Liaoning, China, have a high rate of dental caries. Residents with a history of toothache and smoking habits are more susceptible to the disease. The GRNN early warning model is an accurate and meaningful tool for screening, early diagnosis, and treatment planning for geriatric individuals with a high risk of caries., Competing Interests: The authors declare that they have no competing interests., (Copyright © 2020 Lu Liu et al.)

This study examined over 20 fungal specimens of the Orbiliaceae (Orbiliomycetes) from different regions in China. Our analyses based on morphological traits and the ITS rDNA sequences revealed two new Orbilia species with drechslerella-like asexual morphs. These new species are able to trap nematodes with constricting rings. In addition, Orbilia cf. orientalis is reported as a new cryptic Chinese variant of European collections of O. orientalis . All three species are described and illustrated in detail in this paper. Their phylogenetic relationships with other orbiliaceous species were identified based on their ITS sequences.

During the past 40 years, more than 400 Sudden Unexplained Deaths (SUDs) have occurred in Yunnan, southwestern China. Epidemiological and toxicological analyses suggested that a newly discovered mushroom called Trogia venenata was the leading culprit for SUDs. At present, relatively little is known about the genetics and natural history of this mushroom. In this study, we analyzed the sequence variation at four DNA fragments among 232 fruiting bodies of T. venenata collected from seven locations. Our ITS sequence analyses confirmed that all the isolates belonged to the same species. The widespread presence of sequence heterozygosity within many strains at each of three protein-coding genes suggested that the fruiting bodies were diploid, dikaryotic or heterokaryotic. Within individual geographic populations, we found significant deviations of genotype frequencies from Hardy-Weinberg expectations, with the overall observed heterozygosity lower than that expected under random mating, consistent with prevalent inbreeding within local populations. The geographic populations were overall genetically differentiated. Interestingly, while a positive correlation was found between population genetic distance and geographic distance, there was little correlation between genetic distance and barium concentration difference for the geographic populations. Our results suggest frequent inbreeding, geographic structuring, and limited gene flow among geographic populations of T. venenata from southwestern China.

A new species of Orbilia related to O. luteorubella is described mainly based on morphological characters of its asexual morph and molecular data. The sexual morph does not significantly differ from O. luteorubella, whereas the asexual morph obtained from its ascospore isolate resembles members of the non-predacious genus Dactylella, because it has fusiform phragmoconidia borne singly at the apex of conidiophores. Phylogenetic analysis showed that this strain clustered with a clade that included available strains of the O. luteorubella aggregate and was distant from all analysed Dactylella species. Within this clade, the new strain fell between species with filiform conidia and those of a Pseudotripoconidium anamorph. By combining morphological and phylogenetic analyses, we conclude that our isolate belongs to a new taxon. Pleomorphism of the new taxon is described and discussed.

Novel autoregulatory metabolites, arthrosporols A-C (1-3), involved in regulating the morphological switch in fungi, were purified and characterized from the carnivorous fungus Arthrobotrys oligospora. These compounds possess a novel hybrid carbon skeleton consisting of an epoxy-cyclohexenol combined with a rare monocyclic sesquiterpenol substructure. This is the first report of a monocyclic sesquiterpenol of this type of fungal origin. Compounds 1-3 displayed significant inhibitory activities toward the formation of conidiophores, while compounds 1 and 3 showed the opposite effects on the formation of a two-dimensional network with increasing rates of 40-90% and inhibiting rates of 30-90%, respectively.

Malachite green (MG), N-methylated diaminotriphenylmethane, is one of the most common dyes in textile industry and has also been used as an effective antifungal agent. However, due to its negative impact on the environment and carcinogenic effects to mammalian cells, there is a significant interest in developing microbial agents to degrade this type of recalcitrant molecules. Here, an Exiguobacterium sp. MG2 was isolated from a river in Yunnan Province of China as one of the best malachite green degraders. This strain had a high decolorization capability even at the concentration of 2500 mg/l and maintained its stable activity within the pH range from 5.0 to 9.0. High-pressure liquid chromatography, liquid chromatography-mass spectrometry and gas chromatography-mass spectrometry were employed to detect the catabolic pathway of MG. Six intermediate products were identified and a potential biodegradation pathway was proposed. This pathway involves a series of reactions of N-demethylation, reduction, benzene ring-removal, and oxidation, which eventually converted N-methylated diaminotriphenylmethane into N, N-dimethylaniline that is the key precursor to MG. Furthermore, our molecular biology experiments suggested that both triphenylmethane reductase gene tmr and cytochrome P450 participated in MG degradation, consistent with their roles in the proposed pathway. Collectively, our investigation is the first report on a biodegradation pathway of triphenylmethane dye MG in bacteria.

Six indole alkaloids with various levels of prenylation were isolated from the thermophilic fungus Talaromyces thermophilus strain YM3-4. Their structures were identified by NMR and MS spectroscopic analyses. Compounds 1 and 2 are new analogues of the key versatile precursor notoamide E. Compound 3 is a novel analogue of preechinulin, and compound 4 was reported as a natural occurring cyclo(glycyltryptophyl) for the first time. The metabolite profile of this thermophilic organism displayed a biosynthetic pathway for talathermophilins.

Two novel thermophilic, spore-forming bacterial strains, T-11(T) and E-112(T), were isolated from hot springs in Tengchong and Eryuan counties of Yunnan province in south-west China. The strains were Gram-stain-positive rods, occurring singly or in chains. Growth of strain T-11(T) was observed between 30 and 75 °C (optimum 50 °C) and at pH 7-11 (optimum pH 8.5), while the temperature range for strain E-112(T) was 35-70 °C (optimum 55 °C) and the pH range was 7.0-11.0 (optimum pH 8.0). The DNA G+C contents of strains T-11(T) and E-112(T) were 41.1 and 42.6 mol%, respectively. On the basis of 16S rRNA gene sequence similarity, the two strains were shown to be related most closely to Anoxybacillus species. The chemotaxonomic characteristics [predominant isoprenoid quinone menaquinone 7 (MK-7); major fatty acids iso-C(15 : 0) and iso-C(17 : 0)] also supported the affiliation of strains T-11(T) and E-112(T) to the genus Anoxybacillus. The results of DNA-DNA hybridization and physiological and biochemical tests allowed genotypic and phenotypic differentiation of strains T-11(T) and E-112(T) from Anoxybacillus species with validly published names. Strains T-11(T) and E-112(T) therefore represent two novel species, for which the names Anoxybacillus tengchongensis sp. nov. (type strain T-11(T) =CCTCC AB209237(T) =KCTC 13721(T)) and Anoxybacillus eryuanensis sp. nov. (type strain E-112(T) =CCTCC AB209236(T) =KCTC 13720(T)) are proposed.

An Achromobacter xylosoxidans MG1 strainisolated from the effluent treatment plant of a textile and dyeing factory from Yunnan Province in China was found capable of decolorizing the malachite green dye at a high efficacy. Strain MG1 reduced 86% malachite green at the concentration of 2,000 mg/l within 1 h, representing a greater ability for decolorizing and a higher tolerance of this compound than all previously reported bacteria. Color removal was optimal at pH 6 and 38°C. Further experimental evidences demonstrated that both cytoplasmic and extracellular biodegradation contributed to the decolorization of malachite green. Nested PCR was employed to identify the candidate genes responsible for malachite green decolorization, and we identified a cytoplasmic triphenylmethane reductase gene with 100% amino acid similarity to the corresponding gene in Citrobacter sp. strain. In contrast to our expectation, the addition of metyrapone had little effect on the cytoplasmic biodegradation, suggesting that cytochrome P450 was not involved in the high-performance reduction. The extracellular biodegradation was likely attributable to the secretion of extracellular proteases and some heat-resistant compounds., (Copyright © 2011 S. Karger AG, Basel.)

A new anamorphic fungus is described based on four isolates from ascospores of Orbilia aff. luteorubella. This fungus differs from previously known Orbilia anamorphs in producing inversely pyramidal, unicellular conidia with several protuberances at their distal end. Conidia produce 1-7 prominent denticles that emerge from a node at the conidiophore apex. Conidiogenesis is holoblastic. Because phylogenetic analysis indicated greater than 90% ITS sequence similarities among the four isolates they are treated here as a single species. In the sequence analysis of the internal transcribed spacer region (ITS) these isolates and other sequences identified as O. aff. luteorubella were nested within Orbilia and formed a clade with 99% bootstrap support. This clade is separated from nematode-trapping species of Orbilia. Based on both morphological and molecular analyses, we propose a new genus, Pseudotripoconidium.

The geothermal sites near neutral and alkalescent thermal springs in Tengchong Rehai National Park were examined through cultivation-dependent approach to determine the diversity of thermophilic fungi in these environments. Here, we collected soils samples in this area, plated on agar media conducive for fungal growth, obtained pure cultures, and then employed the method of internal transcribed spacer (ITS) sequencing combined with morphological analysis for identification of thermophilic fungi to the species level. In total, 102 strains were isolated and identified as Rhizomucor miehei, Chaetomium sp., Talaromyces thermophilus, Talaromyces byssochlamydoides, Thermoascus aurantiacus Miehe var. levisporus, Thermomyces lanuginosus, Scytalidium thermophilum, Malbranchea flava, Myceliophthora sp. 1, Myceliophthora sp. 2, Myceliophthora sp. 3, and Coprinopsis sp. Two species, T. lanuginosus and S. thermophilum were the dominant species, representing 34.78% and 28.26% of the sample, respectively. Our results indicated a greater diversity of thermophilic fungi in neutral and alkaline geothermal sites than acidic sites around hot springs reported in previous studies. Most of our strains thrived at alkaline growth conditions.

The experiment was conducted to investigate the effects of different forms of nitrogen application (ammonium, NH4(+) -N; nitrate, NO3(-) -N; and amide-N, NH2-N) and different concentrations (40, 200 and 800 mg/L) on N2O flux from the fluvo-aquic soil in a lab-simulated freezing and thawing process. N2O flux slowly decreased with soil freezing, and then increased slowly with soil thawing, reaching a peak at the initial thawing stage. The average N2O fluxes with addition of NH4(+) -N, NO3(-) -N and NH2 -N are 119.01, 611.61 and 148.22 microg x (m2 x h) (-1) respectively at the concentration of 40 mg/L; 205.28, 1084.40 and 106.13 microg x (m2 x h)(-1) at the concentration of 200 mg/L; 693.95, 1 820.02 and 49.74 microg x (m2 x h)(-1) at the concentration of 800 mg/L. The control is only 100.35 microg x (m2 x h)(-1). N2O flux with addition of NH4(+) -N and NO3(-) -N increased with increasing concentration, ranging from 17.49% to 425.67% for NH4(+) -N, and 563.38% to 1 458.6% for NO3(-) -N compared with control. There was a time lag achieving stable N2O emission flux with concentration increase. In contrast, by adding NH2 -N to soil, N2O flux decreased with increasing concentration. In sum, inorganic nitrogen such as NH4(+) -N or NO3(-) -N fertilizer incorporated in soil enhanced the cumulative N2O flux from the fluvo-aquic soil relative to amide-N. This study suggested that ammonium and nitrate concentration in overwintering water should be less than 200 mg/L and 40 mg/L in order to reduce N2O emissions from soil, regardless of amide-N.

A new Dactylella species, Dactylella alba was isolated from the ascospores of Orbilia alba collected in Wenshan County, Yunnan Province, China. Conidiophores were either not branched or occasionally branched, bearing divergent sterigmata on the tip with single conidium on each. Conidia were elongated ellipsoids, 1-2 septate, mostly 1 septate. By combining the ITS sequence with morphological characteristics, a new anamorphic species is described and illustrated together with its teleomorph.

Two new nematode-trapping fungi, Dactylellina sichuanensis and D. varietas from China, which capture nematodes by both adhesive knobs and non-constricting rings, are described and illustrated. D. sichuanensis is characterized by both adhesive knobs and non-constricting rings, solitary conidiophores and 3-(4)-6 septate conidia, as compared with species such as D. appendiculata, D. candida, D. leptospora and D. lysipaga. Although D. sichuanensis shares similar types of trapping devices, the presence of simple conidiophores and spindle-shaped conidia with these species, it can be distinguished by its larger conidia and presence of more than four septa. In D. sichuanensis, a single conidium is born at the tip of conidiophore, while in D. candida, 3-10 conidia are born near the apex of conidiophore in a capitate arrangement. It produces spindle-shaped conidia with 3-6 septa, whereas D. leptospora produces cylindrical-shaped conidia with 5-15 septa. D. appendiculata captures nematodes by adhesive knobs whereas D. sichuanensis captures nematodes by both adhesive knobs and non-constricting rings. They also differ in conidial size (35-82.5mum in D. sichuanensis as compared with 57-108mum in D. appendiculata). D. varietas is characterized by conidiophores that are branched at right-angles, and elongate to fusoid conidia, with 7-8 septa (more than 25% of which are curved). D. varietas resembles D. asthenopaga, Dactylella oxyspora and Monacrosporium multiseptatum, but has elongate-fusoid conidia, whereas D. asthenopaga possesses obconical or clavate conidia. D. varietas forms both adhesive knobs and non-constricting rings whereas Dactylella oxyspora does not produce any trapping device. M. multiseptatum differs from D. varietas in having larger conidia with an inflated middle cell. Phylogenetic analyses based on nuclear and protein coding DNA sequences (18 S, and a combined 28 S+5.8 S+beta-tubulin dataset) indicate that these two taxa should be assigned to the family Orbiliaceae.

Five new verticillin-type epipolysulfanyldioxopiperazines, gliocladine A (1), B (2), C (3), D (4), and E (5), were isolated from wheat solid-substrate fermentation of Gliocladium roseum 1A, along with four known compounds, verticillin A (6), 11'-deoxyverticillin A (7), Sch52900 (8), and Sch52901 (9). Their structures were elucidated by extensive 1D and 2D NMR studies, MS, and chemical transformations. In vitro immersion tests showed that all nine compounds exhibited antinematodal activity against Caenorhabditis elegans and Panagrellus redivivus. The monomeric epipolysulfanydioxopiperazines (3-5), with the indole moiety, were found to be less active than the dimeric compounds (1, 2, 6-8).

An endospore-forming bacterium, designated strain B-16T, was isolated from a forest soil sample in Yunnan, China. The isolate presented remarkable nematotoxic activity against nematode Panagrellus redivivus. The organism was strictly aerobic, motile, spore forming and rod shaped, catalase- and oxidase-positive. The predominant isoprenoid quinone was menaquinone 7 (MK-7). The major cellular fatty acid profiles were anteiso-C15:0 (48.67%), iso-C15:0 (13.45%), C16:0 (9.06%) and anteiso-Cl7:0 (8.29%). The DNA G+C content was 46%. Phylogenetic analyses based on 16S rDNA sequence revealed that isolate belongs to the genus Bacillus. Strain B-16T exhibited high 16S rDNA similarity with its closest neighbors Bacillus vallismortis (99.79%), B. subtilis (99.43%), B. atrophaeus (99.43%), B. amyloliquefaciens (99.36%), B. licheniformis (98.0%) and less than 97.0% with all the other relative type strains in the genus Bacillus. The phenotypic and genotypic characteristics and DNA-DNA relatedness data indicate that strain B-16T should be distinguished from all the relative species of genus Bacillus. Therefore, on the basis of the polyphasic taxonomic data presented, a new species of the genus Bacillus, B. nematocida, with the type strain B-16T ( = CGMCC 1128T) is proposed. The GenBank accession number for the sequence reported in this paper is AY820954.