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1.
Microbiol Spectr ; : e0420223, 2024 Jun 14.
Article in English | MEDLINE | ID: mdl-38874428

ABSTRACT

The underlying mechanism of thermotolerance, which is a key virulence factor essential for pathogenic fungi such as Cryptococcus neoformans, is largely unexplored. In this study, our findings suggest that Set302, a homolog of Set3 and a subunit of histone deacetylase complex Set3C, contributes to thermotolerance in C. neoformans. Specifically, the deletion of the predicted Set3C core subunit, Set302, resulted in further reduction in the growth of C. neoformans at 39°C, and survival of transient incubation at 50°C. Transcriptomics analysis revealed that the expression levels of numerous heat stress-responsive genes altered at both 30°C and 39°C due to the lack of Set302. Notably, at 39°C, the absence of Set302 led to the downregulation of gene expression related to the ubiquitin-proteasome system (UPS). Based on the GFP-α-synuclein overexpression model to characterize misfolded proteins, we observed a pronounced accumulation of misfolded GFP-α-synuclein at 39°C, consequently inhibiting C. neoformans thermotolerance. Furthermore, the loss of Set302 exacerbated the accumulation of misfolded GFP-α-synuclein during heat stress. Interestingly, the set302∆ strain exhibited a similar phenotype under proteasome stress as it did at 39°C. Moreover, the absence of Set302 led to reduced production of capsule and melanin. set302∆ strain also displayed significantly reduced pathogenicity and colonization ability compared to the wild-type strain in the murine infection model. Collectively, our findings suggest that Set302 modulates thermotolerance by affecting the degradation of misfolded proteins and multiple virulence factors to mediate the pathogenicity of C. neoformans.IMPORTANCECryptococcus neoformans is a pathogenic fungus that poses a potential and significant threat to public health. Thermotolerance plays a crucial role in the wide distribution in natural environments and host colonization of this fungus. Herein, Set302, a critical core subunit for the integrity of histone deacetylase complex Set3C and widely distributed in various fungi and mammals, governs thermotolerance and affects survival at extreme temperatures as well as the formation of capsule and melanin in C. neoformans. Additionally, Set302 participates in regulating the expression of multiple genes associated with the ubiquitin-proteasome system (UPS). By eliminating misfolded proteins under heat stress, Set302 significantly contributes to the thermotolerance of C. neoformans. Moreover, Set302 regulates the pathogenicity and colonization ability of C. neoformans in a murine model. Overall, this study provides new insight into the mechanism of thermotolerance in C. neoformans.

2.
Sci China Life Sci ; 67(5): 1061-1068, 2024 May.
Article in English | MEDLINE | ID: mdl-38418758

ABSTRACT

Although transvaginal mesh (TVM) repair is no longer used in some countries, long-term outcomes after TVM surgery are of great importance globally. However, reports with follow-up >10 years are limited. Thus, this study aimed to report outcomes in a prospective cohort with at least 10 years of follow-up. Women with stage III-IV symptomatic prolapse were approached consecutively from 2008 to 2013 at one tertiary hospital. The main outcome measure was symptomatic failure. Secondary outcomes included anatomic failure, recurrence, patient satisfaction, complications, and reoperation. The Kaplan-Meier curve was used to estimate the cumulative failure rate. Of the 121 patients enrolled in the study, 103 (85.1%) completed a median follow-up of 11 years. The estimated probability rates of symptomatic and anatomic failure were 17.6% and 8.8% in 11 years, respectively. The estimated incidence of symptomatic failure increased by 8.2% between 5 and 11 years; however, the corresponding rate for anatomic failure was 3.7%. The most common complication was vaginal mesh exposure, and its estimated probability increased from 19.3% to 28.4% from 5 to 11 years, respectively. Office trimming resolved 80.0% of vaginal exposures. These patients did not report decreased overall satisfaction. Patients with vaginal mesh exposure requiring>3 office procedures or mesh removal in the operating room (5.8% by 11 years) had lower satisfaction rates (P<0.01) and were defined as having severe mesh exposure. The rates of postoperative pain, reoperation, and Patient Global Impression of Improvement ⩾2 were 2.5%, 3.3%, and 94.2%, respectively. The results of this study implied that TVM treatment gradually increased the symptomatic failure rate but provided durable anatomical support of the vaginal wall. Vaginal mesh exposure was common in women who were largely not sexually active; however, 80% of the cases could be managed in the outpatient clinic, which did not affect patient satisfaction.


Subject(s)
Pelvic Organ Prolapse , Reoperation , Surgical Mesh , Humans , Female , Surgical Mesh/adverse effects , Follow-Up Studies , Middle Aged , Aged , Treatment Outcome , Pelvic Organ Prolapse/surgery , Reoperation/statistics & numerical data , Prospective Studies , Patient Satisfaction , Vagina/surgery , Postoperative Complications/epidemiology , Postoperative Complications/etiology , Kaplan-Meier Estimate , Recurrence , Cohort Studies
3.
Elife ; 132024 Jan 22.
Article in English | MEDLINE | ID: mdl-38251723

ABSTRACT

Cryptococcus neoformans poses a threat to human health, but anticryptococcal therapy is hampered by the emergence of drug resistance, whose underlying mechanisms remain poorly understood. Herein, we discovered that Isw1, an imitation switch chromatin remodeling ATPase, functions as a master modulator of genes responsible for in vivo and in vitro multidrug resistance in C. neoformans. Cells with the disrupted ISW1 gene exhibited profound resistance to multiple antifungal drugs. Mass spectrometry analysis revealed that Isw1 is both acetylated and ubiquitinated, suggesting that an interplay between these two modification events exists to govern Isw1 function. Mutagenesis studies of acetylation and ubiquitination sites revealed that the acetylation status of Isw1K97 coordinates with its ubiquitination processes at Isw1K113 and Isw1K441 through modulating the interaction between Isw1 and Cdc4, an E3 ligase. Additionally, clinical isolates of C. neoformans overexpressing the degradation-resistant ISW1K97Q allele showed impaired drug-resistant phenotypes. Collectively, our studies revealed a sophisticated acetylation-Isw1-ubiquitination regulation axis that controls multidrug resistance in C. neoformans.


Subject(s)
Cryptococcosis , Cryptococcus neoformans , Saccharomyces cerevisiae Proteins , Humans , Chromatin , Cryptococcus neoformans/genetics , Saccharomyces cerevisiae/genetics , Acetylation , Imitative Behavior , Adenosine Triphosphatases/metabolism , Ubiquitination , Drug Resistance, Multiple , DNA-Binding Proteins/metabolism , Saccharomyces cerevisiae Proteins/metabolism
4.
Antimicrob Agents Chemother ; 68(2): e0093723, 2024 Feb 07.
Article in English | MEDLINE | ID: mdl-38169282

ABSTRACT

Entering a dormant state is a prevailing mechanism used by bacterial cells to transiently evade antibiotic attacks and become persisters. The dynamic progression of bacterial dormancy depths driven by protein aggregation has been found to be critical for antibiotic persistence in recent years. However, our current understanding of the endogenous genes that affects dormancy depth remains limited. Here, we discovered a novel role of phage shock protein A (pspA) gene in modulating bacterial dormancy depth. Deletion of pspA of Escherichia coli resulted in increased bacterial dormancy depths and prolonged lag times for resuscitation during the stationary phase. ∆pspA exhibited a higher persister ratio compared to the wild type when challenged with various antibiotics. Microscopic images revealed that ∆pspA showed accelerated formation of protein aggresomes, which were collections of endogenous protein aggregates. Time-lapse imaging established the positive correlation between protein aggregation and antibiotic persistence of ∆pspA at the single-cell level. To investigate the molecular mechanism underlying accelerated protein aggregation, we performed transcriptome profiling and found the increased abundance of chaperons and a general metabolic slowdown in the absence of pspA. Consistent with the transcriptomic results, the ∆pspA strain showed a decreased cellular ATP level, which could be rescued by glucose supplementation. Then, we verified that replenishment of cellular ATP levels by adding glucose could inhibit protein aggregation and reduce persister formation in ∆pspA. This study highlights the novel role of pspA in maintaining proteostasis, regulating dormancy depth, and affecting antibiotic persistence during stationary phase.


Subject(s)
Anti-Bacterial Agents , Protein Aggregates , Anti-Bacterial Agents/pharmacology , Escherichia coli/genetics , Adenosine Triphosphate/metabolism , Glucose/metabolism
5.
Int Urogynecol J ; 35(1): 59-67, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37542565

ABSTRACT

INTRODUCTION AND HYPOTHESIS: The objective was to evaluate the efficacy of pessaries in the treatment of stage IV pelvic organ prolapse (POP) and identify the influencing factors. METHODS: One hundred and fifty-seven patients with stage IV symptomatic POP were admitted to the hospital for pessary fitting. A successful pessary fitting was defined as a patient fitted with a pessary at the initial fitting in whom use continued 2 weeks later. The rates of successful pessary fitting, patient satisfaction, remission of prolapse and urinary symptoms, and the occurrence of factors associated with successful pessary fitting were calculated and predictors of appropriate pessary type selection were analyzed. RESULTS: A total of 130 patients with stage IV POP had a successful pessary fitting (82.8%). The satisfaction rate associated with the two types of pessaries was more than 90%. The success rate among patients undergoing a ring pessary fitting trial was 44.6%, and 84.3% of the patients were self-managed. Prolapse symptoms significantly improved in 90% of cases, and urinary symptoms improved in 58-93% of cases from baseline. The number of vaginal deliveries, history of hysterectomy and vaginal introitus/total vaginal length (TVL) ratio were independent risk factors associated with unsuccessful pessary fitting. CONCLUSION: For patients with stage IV POP, the successful fitting rate is as high as 80% or more. More vaginal deliveries, a history of hysterectomy, and a larger vaginal introitus/TVL ratio (ratio >0.6) were predictors of unsuccessful pessary fitting.


Subject(s)
Pelvic Organ Prolapse , Pessaries , Female , Humans , Prospective Studies , Pelvic Organ Prolapse/therapy , Vagina , Patient Satisfaction , Treatment Outcome
6.
J Antimicrob Chemother ; 79(1): 128-133, 2024 Jan 03.
Article in English | MEDLINE | ID: mdl-37991189

ABSTRACT

OBJECTIVES: We explored the epidemiological and molecular characteristics of Candida parapsilosis sensu stricto isolates in China, and their mechanisms of azole resistance. METHODS: Azole susceptibilities of 2318 non-duplicate isolates were determined using CLSI broth microdilution. Isolates were genotyped by a microsatellite typing method. Molecular resistance mechanisms were also studied and functionally validated by CRISPR/Cas9-based genetic alterations. RESULTS: Fluconazole resistance occurred in 2.4% (n = 56) of isolates, and these isolates showed a higher frequency of distribution in ICU inpatients compared with susceptible isolates (48.2%, n = 27/56 versus 27.8%, 613/2208; P = 0.019). Microsatellite-genotyping analysis yielded 29 genotypes among 56 fluconazole-resistant isolates, of which 10 genotypes, including 37 isolates, belonged to clusters, persisting and transmitting in Chinese hospitals for 1-29 months. Clusters harbouring Erg11Y132F (5/10; 50%) were predominant in China. Among these, the second most dominant cluster MT07, including seven isolates, characteristically harbouring Erg11Y132F and Mrr1Q625K, lent its carriage to being one of the strongest associations with cross-resistance and high MICs of fluconazole (>256 mg/L) and voriconazole (2-8 mg/L), causing transmission across two hospitals. Among mutations tested, Mrr1Q625K led to the highest-level increase of fluconazole MIC (32-fold), while mutations located within or near the predicted transcription factor domain of Tac1 (D440Y, T492M and L518F) conferred cross-resistance to azoles. CONCLUSIONS: This study is the first Chinese report of persistence and transmissions of multiple fluconazole-resistant C. parapsilosis sensu stricto clones harbouring Erg11Y132F, and the first demonstration of the mutations Erg11G307A, Mrr1Q625K, Tac1L263S, Tac1D440Y and Tac1T492M as conferring resistance to azoles.


Subject(s)
Candida parapsilosis , Fluconazole , Fluconazole/pharmacology , Candida parapsilosis/genetics , Antifungal Agents/pharmacology , Azoles/pharmacology , China/epidemiology , Microbial Sensitivity Tests , Drug Resistance, Fungal/genetics
7.
J Clin Microbiol ; 61(11): e0080623, 2023 11 21.
Article in English | MEDLINE | ID: mdl-37877725

ABSTRACT

The infection proportion of Candida orthopsilosis, a member of the C. parapsilosis complex, has increased globally in recent years, and nosocomial outbreaks have been reported in several countries. This study aimed to establish microsatellite loci-based typing method that was able to effectively distinguish among C. orthopsilosis isolates. Three reference C. orthopsilosis genome sequences were analyzed to identify repeat loci. DNA sequences containing over eight bi- or more nucleotide repeats were selected. A total of 51 loci were initially identified, and locus-specific primers were designed and tested with 20 epidemiologically unrelated isolates. Four loci with excellent reproducibility, specificity, and resolution for molecular typing purposes were identified, and the combined discriminatory power (DP, based on 20 epidemiologically unrelated isolates) of these four loci was 1.0. Reproducibility was demonstrated by consistently testing three strains each in triplicate, and stability, demonstrated by testing 10 successive passages. Then, we collected 48 C. orthopsilosis non-duplicate clinical isolates from the China Hospital Invasive Fungal Surveillance Net study to compare the DP of the microsatellite-based typing with internal transcribed spacer (ITS) and amplified fragment length polymorphism (AFLP) typing analyses, using ATCC 96139 as a reference strain. These 49 isolates were subdivided into 12 microsatellite types (COMT1-12), six AFLP types, and three ITS types, while all the isolates with the same COMT belonged to consistent AFLP and ITS type, demonstrating the high DP of our microsatellite-type method. According to our results, COMT12 was found to be the predominant type in China, and COMT5 was the second largest and responsible for causing a nosocomial outbreak. This microsatellite-type method is a valuable tool for the differentiation of C. orthopsilosis and could be vital for epidemiological studies to determine strain relatedness and monitor transmission.


Subject(s)
Candidiasis , Cross Infection , Humans , Candida parapsilosis , Candida/genetics , Amplified Fragment Length Polymorphism Analysis , Candidiasis/diagnosis , Candidiasis/epidemiology , Cross Infection/epidemiology , Cross Infection/microbiology , Reproducibility of Results , Hospitals , Disease Outbreaks , Genotype , Microsatellite Repeats , Mycological Typing Techniques/methods
8.
Mol Plant ; 16(10): 1547-1563, 2023 10 02.
Article in English | MEDLINE | ID: mdl-37660255

ABSTRACT

Photosynthesis in crops and natural vegetation allows light energy to be converted into chemical energy and thus forms the foundation for almost all terrestrial trophic networks on Earth. The efficiency of photosynthetic energy conversion plays a crucial role in determining the portion of incident solar radiation that can be used to generate plant biomass throughout a growth season. Consequently, alongside the factors such as resource availability, crop management, crop selection, maintenance costs, and intrinsic yield potential, photosynthetic energy use efficiency significantly influences crop yield. Photosynthetic efficiency is relevant to sustainability and food security because it affects water use efficiency, nutrient use efficiency, and land use efficiency. This review focuses specifically on the potential for improvements in photosynthetic efficiency to drive a sustainable increase in crop yields. We discuss bypassing photorespiration, enhancing light use efficiency, harnessing natural variation in photosynthetic parameters for breeding purposes, and adopting new-to-nature approaches that show promise for achieving unprecedented gains in photosynthetic efficiency.


Subject(s)
Photosynthesis , Plant Breeding , Crops, Agricultural , Nutrients , Food Security
9.
Emerg Microbes Infect ; 12(2): 2244087, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37526401

ABSTRACT

Systemic infection with Cryptococcus neoformans, a dangerous and contagious pathogen found throughout the world, frequently results in lethal cryptococcal pneumonia and meningoencephalitis, and no effective treatments and vaccination of cryptococcosis are available. Here, we describe Prm1, a novel regulator of C. neoformans virulence. C. neoformans prm1Δ cells exhibit extreme sensitivity to various environmental stress conditions. Furthermore, prm1Δ cells show deficiencies in the biosynthesis of chitosan and mannoprotein, which in turn result in impairment of cell wall integrity. Treatment of mice with heat-killed prm1Δ cells was found to facilitate the host immunological defence against infection with wild-type C. neoformans. Further investigation demonstrated that prm1Δ cells strongly promote pulmonary production of interferon-γ, leading to activation of macrophage M1 differentiation and inhibition of M2 polarization. Therefore, our findings suggest that C. neoformans Prm1 may be a viable target for the development of anti-cryptococcosis medications and, cells lacking Prm1 represent a promising candidate for a vaccine.


Subject(s)
Cryptococcosis , Cryptococcus neoformans , Animals , Mice , Hot Temperature , Cryptococcosis/prevention & control , Cryptococcus neoformans/genetics , Vaccination , Immunization
10.
Carbohydr Polym ; 319: 121196, 2023 Nov 01.
Article in English | MEDLINE | ID: mdl-37567723

ABSTRACT

Customizable structures and patterns are becoming powerful tools for biomimetic design and application of soft materials. The construction of long-range ordered self-wrinkled structures on multi-dimensional and complex-shaped surfaces with facile, fast and efficient strategies still faces serious challenges. During the stretch-recovery process, the carboxyl groups in the polyacrylamide/sodium alginate dual network gel form robust coordination with Fe3+ to achieve a hard shell layer, resulting in a modulus mismatch between the inner soft layer and the outer hard layer, thereby forming a wrinkled surface. This flexible strategy allows simultaneous construction of complex topologies from 1D to 3D wits well-organized microstructure and controllable dimensions. The mechanism of the influence of ion treating time and pre-stretching ratio on wrinkle wavelength was explored in detail. The finite element simulations matched well with the experimental results. Due to the unique surface and dual crosslinking network, the self-wrinkled hydrogel maintains a high sensitivity of up to 67.47 kPa-1 in 1000 compression cycles. As a high-sensitivity pressure sensor integrated into the detection system, it can be efficiently applied to the contact dynamic tactile perception and monitoring of various movement behaviors of the human body.

11.
Front Cell Infect Microbiol ; 13: 1195968, 2023.
Article in English | MEDLINE | ID: mdl-37168390

ABSTRACT

Cryptococcus species are opportunistic human fungal pathogens. Survival in a hostile environment, such as the elevated body temperatures of transmitting animals and humans, is crucial for Cryptococcus infection. Numerous intriguing investigations have shown that the Hsf family of thermotolerance transcription regulators plays a crucial role in the pathogen-host axis of Cryptococcus. Although Hsf1 is known to be a master regulator of the heat shock response through the activation of gene expression of heat shock proteins (Hsps). Hsf1 and other Hsfs are multifaceted transcription regulators that regulate the expression of genes involved in protein chaperones, metabolism, cell signal transduction, and the electron transfer chain. In Saccharomyces cerevisiae, a model organism, Hsf1's working mechanism has been intensively examined. Nonetheless, the link between Hsfs and Cryptococcus pathogenicity remains poorly understood. This review will focus on the transcriptional regulation of Hsf function in Cryptococcus, as well as potential antifungal treatments targeting Hsf proteins.


Subject(s)
Cryptococcus , Transcription Factors , Animals , Humans , Heat Shock Transcription Factors/genetics , Heat Shock Transcription Factors/metabolism , Transcription Factors/metabolism , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Cryptococcus/genetics , Cryptococcus/metabolism , Heat-Shock Proteins/genetics , Heat-Shock Proteins/metabolism , Heat-Shock Response , Saccharomyces cerevisiae/genetics
12.
Adv Sci (Weinh) ; 10(17): e2206056, 2023 06.
Article in English | MEDLINE | ID: mdl-37083223

ABSTRACT

Millions of adenosine (A) to inosine (I) RNA editing events are reported and well-studied in eukaryotes; however, many features and functions remain unclear in prokaryotes. By combining PacBio Sequel, Illumina whole-genome sequencing, and RNA Sequencing data of two Klebsiella pneumoniae strains with different virulence, a total of 13 RNA editing events are identified. The RNA editing event of badR is focused, which shows a significant difference in editing levels in the two K. pneumoniae strains and is predicted to be a transcription factor. A hard-coded Cys is mutated on DNA to simulate the effect of complete editing of badR. Transcriptome analysis identifies the cellular quorum sensing (QS) pathway as the most dramatic change, demonstrating the dynamic regulation of RNA editing on badR related to coordinated collective behavior. Indeed, a significant difference in autoinducer 2 activity and cell growth is detected when the cells reach the stationary phase. Additionally, the mutant strain shows significantly lower virulence than the WT strain in the Galleria mellonella infection model. Furthermore, RNA editing regulation of badR is highly conserved across K. pneumoniae strains. Overall, this work provides new insights into posttranscriptional regulation in bacteria.


Subject(s)
Klebsiella pneumoniae , Quorum Sensing , Virulence/genetics , Klebsiella pneumoniae/genetics , Quorum Sensing/genetics , RNA Editing/genetics , Whole Genome Sequencing
13.
Front Microbiol ; 14: 1113817, 2023.
Article in English | MEDLINE | ID: mdl-37007533

ABSTRACT

Objective: To investigate whether an incubation time of 5 days (Aerobic/F, Anaerobic/F) and 14 days (Myco/F) blood culture bottles is sufficient to prevent false-negative results. Methods: We evaluated 1,244 blood bottles (344 patients) defined as negative by the BACTEC™ FX system. We also reviewed published cases and our own cases of bloodstream infection caused by Cryptococcus neoformans and simulated different scenarios, including different inoculation concentrations, bottle types, and clinical isolates. Results: Two bottles (0.16%) were found to contain C. neoformans when subcultured and Gram stained. A 5-day protocol with Aerobic/F bottles was insufficient for the growth of C. neoformans in some cases, and C. neoformans grew better in Myco/F bottles than in Aerobic/F bottles. Conclusion: Subculturing and Gram staining after a 5-day protocol were important for the detection of C. neoformans, and Myco/F bottles should be collected for the blood culture of C. neoformans.

14.
Future Microbiol ; 18: 87-91, 2023 01.
Article in English | MEDLINE | ID: mdl-36511165

ABSTRACT

WHAT IS THIS SUMMARY ABOUT?: Molds are types of fungus that can cause sickness and death. Mold infections are increasing in China. Until 2022, medicines that can effectively treat all mold infections were still lacking in China. This summary of a study originally published in the journal Infection and Drug Resistance. The study took place in China and tested a medicine called isavuconazole on mold samples to check if isavuconazole can be used to treat mold infections. Isavuconazole became available in China in January 2022 as a capsule (a hard gel-covered pill filled with a dose of medicine) and in June 2022 as an injection or a shot. WHAT WERE THE RESULTS?: Isavuconazole stopped the growth of most molds. Other medicines were needed at higher amounts to stop the growth of molds. WHAT DO THE RESULTS OF THE STUDY MEAN?: Isavuconazole is another option to treat mold infections in China.


Subject(s)
Aspergillosis , Mucormycosis , Humans , Antifungal Agents/pharmacology , Antifungal Agents/therapeutic use , Aspergillosis/drug therapy , Mucormycosis/drug therapy , Fungi , Nitriles/pharmacology , Nitriles/therapeutic use , China
15.
Emerg Microbes Infect ; 12(1): 2153086, 2023 Dec.
Article in English | MEDLINE | ID: mdl-36440795

ABSTRACT

Candida parapsilosis is becoming a predominant non-albicans cause of invasive candidiasis (IC). Echinocandins are the preferred choice for IC treatment and prophylaxis. Resistance to echinocandins in C. parapsilosis has emerged in several countries, but little is known about the susceptibility profile in China or about mechanisms of resistance. Here, we investigated the echinocandin susceptibilities of 2523 C. parapsilosis isolates collected from China and further explored the resistance mechanism among echinocandin-resistant isolates. Anidulafungin exhibited the highest MICs (MIC50/90, 1 and 2 µg/mL; GM, 0.948 µg/mL), while caspofungin showed better activity (0.5 and 1 µg/mL; 0.498 µg/mL). Significantly higher echinocandin MICs were observed among blood-derived isolates compared to others, especially for caspofungin (GM, 1.348 µg/mL vs 0.478 µg/mL). Isolates from ICU and surgical wards also showed higher MICs. Twenty isolates showed intermediate phenotypes for at least one echinocandin. One was resistant to all three echinocandins, fluconazole and voriconazole, which caused breakthrough IC during long-term exposure to micafungin. WGS revealed this isolate carried a mutation S656P in hotspot1 region of Fks1. Bioinformatics analyses suggested that this mutation might lead to an altered protein conformation. CRISPR Cas9-mediated introduction of this mutation into a susceptible reference C. parapsilosis strain increased MICs of all echinocandins 64-fold, with similar results found in the subspecies, C. orthopsilosis and C. metapsilosis. This is the first report of a multi-azole resistant and pan-echinocandin resistant C. parapsilosis isolate, and the identification of a FKS1S656P conferring pan-echinocandin resistance. Our study underscores the necessity of rigorous management of antifungal use and of monitoring for antifungal susceptibility.


Subject(s)
Antifungal Agents , Candidemia , Antifungal Agents/pharmacology , Antifungal Agents/therapeutic use , Candida parapsilosis/drug effects , Candida parapsilosis/genetics , Candidemia/drug therapy , Candidemia/microbiology , Caspofungin/pharmacology , China , Echinocandins/pharmacology , Echinocandins/therapeutic use , Microbial Sensitivity Tests , Humans , Drug Resistance, Fungal
16.
Front Microbiol ; 13: 1021236, 2022.
Article in English | MEDLINE | ID: mdl-36312928

ABSTRACT

The use of morphology to diagnose invasive mould infections in China still faces substantial challenges, which often leads to delayed diagnosis or misdiagnosis. We developed a model called XMVision Fungus AI to identify mould infections by training, testing, and evaluating a ResNet-50 model. Our research achieved the rapid identification of nine common clinical moulds: Aspergillus fumigatus complex, Aspergillus flavus complex, Aspergillus niger complex, Aspergillus terreus complex, Aspergillus nidulans, Aspergillus sydowii/Aspergillus versicolor, Syncephalastrum racemosum, Fusarium spp., and Penicillium spp. In our study, the adaptive image contrast enhancement enabling XMVision Fungus AI as a promising module by effectively improve the identification performance. The overall identification accuracy of XMVision Fungus AI was up to 93.00% (279/300), which was higher than that of human readers. XMVision Fungus AI shows intrinsic advantages in the identification of clinical moulds and can be applied to improve human identification efficiency through training. Moreover, it has great potential for clinical application because of its convenient operation and lower cost. This system will be suitable for primary hospitals in China and developing countries.

17.
Nat Commun ; 13(1): 5407, 2022 09 15.
Article in English | MEDLINE | ID: mdl-36109512

ABSTRACT

Mitochondrial quality control prevents accumulation of intramitochondrial-derived reactive oxygen species (mtROS), thereby protecting cells against DNA damage, genome instability, and programmed cell death. However, underlying mechanisms are incompletely understood, particularly in fungal species. Here, we show that Cryptococcus neoformans heat shock factor 3 (CnHsf3) exhibits an atypical function in regulating mtROS independent of the unfolded protein response. CnHsf3 acts in nuclei and mitochondria, and nuclear- and mitochondrial-targeting signals are required for its organelle-specific functions. It represses the expression of genes involved in the tricarboxylic acid cycle while promoting expression of genes involved in electron transfer chain. In addition, CnHsf3 responds to multiple intramitochondrial stresses; this response is mediated by oxidation of the cysteine residue on its DNA binding domain, which enhances DNA binding. Our results reveal a function of HSF proteins in regulating mtROS homeostasis that is independent of the unfolded protein response.


Subject(s)
Cryptococcus neoformans , Cysteine , Cryptococcus neoformans/genetics , Cryptococcus neoformans/metabolism , Cysteine/metabolism , DNA/metabolism , Homeostasis , Mitochondria/genetics , Mitochondria/metabolism , Reactive Oxygen Species/metabolism
18.
Emerg Microbes Infect ; 11(1): 1572-1585, 2022 Dec.
Article in English | MEDLINE | ID: mdl-35621025

ABSTRACT

Cryptococcal meningoencephalitis (CM) is emerging as an infection in HIV/AIDS patients shifted from primarily ART-naive to ART-experienced individuals, as well as patients with COVID-19 and immunocompetent hosts. This fungal infection is mainly caused by the opportunistic human pathogen Cryptococcus neoformans. Brain or central nervous system (CNS) dissemination is the deadliest process for this disease; however, mechanisms underlying this process have yet to be elucidated. Moreover, illustrations of clinically relevant responses in cryptococcosis are currently limited due to the low availability of clinical samples. In this study, to explore the clinically relevant responses during C. neoformans infection, macaque and mouse infection models were employed and miRNA-mRNA transcriptomes were performed and combined, which revealed cytoskeleton, a major feature of HIV/AIDS patients, was a centric pathway regulated in both infection models. Notably, assays of clinical immune cells confirmed an enhanced macrophage "Trojan Horse" in patients with HIV/AIDS, which could be shut down by cytoskeleton inhibitors. Furthermore, myocilin, encoded by MYOC, was found to be a novel enhancer for the macrophage "Trojan Horse," and an enhanced fungal burden was achieved in the brains of MYOC-transgenic mice. Taken together, the findings from this study reveal fundamental roles of the cytoskeleton and MYOC in fungal CNS dissemination, which not only helps to understand the high prevalence of CM in HIV/AIDS but also facilitates the development of novel therapeutics for meningoencephalitis caused by C. neoformans and other pathogenic microorganisms.


Subject(s)
COVID-19 , Cryptococcosis , Cryptococcus neoformans , HIV Infections , Meningoencephalitis , MicroRNAs , Animals , Brain/pathology , Cryptococcosis/microbiology , Cryptococcus neoformans/genetics , Disease Models, Animal , Humans , Macaca , Meningoencephalitis/microbiology , Mice , MicroRNAs/genetics , Transcriptome
19.
Infect Drug Resist ; 15: 2101-2113, 2022.
Article in English | MEDLINE | ID: mdl-35498631

ABSTRACT

Purpose: Monitoring antifungal susceptibility patterns for new or established antifungals is imperative. Antifungal resistance is frequent in molds, frequently leading to invasive mold infections (IMIs) in immunocompromised patients with high morbidity and mortality. Limited availability of effective antifungals for treatment of IMIs in China is an enormous challenge. The purpose of this study was to monitor in vitro antifungal resistance profiles of mold isolates from China, with a particular focus on evaluating in vitro isavuconazole (ISA) activity against these isolates, contributing to the treatment guidance in clinics. Methods: We evaluated the in vitro activity of ISA and its comparators (voriconazole [VOR] and amphotericin B [AMB]) against 131 clinical isolates of Aspergillus spp. (n = 105) and Mucorales order (n = 26) collected between 2017 and 2020 from China. Results: ISA and VOR exhibited similar in vitro activity against Aspergillus spp., with minimum inhibitory concentration (MIC)50 of 1 µg/mL and MIC90 of 2 µg/mL, respectively. Overall, AMB was less active than azoles against Aspergillus spp. (MIC50: 4 µg/mL, MIC90: 8 µg/mL). Against the Mucorales order, ISA demonstrated MIC50 of 0.5 µg/mL and MIC90 of 1 µg/mL; however, one strain each of Mucor circinelloides and Syncephalastrum racemosum were resistant to ISA (MICs: >8 µg/mL). VOR exhibited little or no activity (MIC50: 8 µg/mL, MIC90: >8 µg/mL) against the Mucorales order, whereas AMB had MIC50 and MIC90 of 1 µg/mL. Conclusion: This was the first multicenter, in vitro study conducted in China and demonstrated the excellent activities of ISA against most species of the Mucorales order. MIC indicated an advantage over currently available azole antifungals, positioning ISA as a potential alternative to VOR for clinical management of IMIs. As with other antimicrobials, clinicians should employ stewardship and best practices in relation to potential resistance to new azole antifungals.

20.
Front Microbiol ; 13: 809642, 2022.
Article in English | MEDLINE | ID: mdl-35479641

ABSTRACT

Early life is a critical window for preventing the intergenerational transmission of metabolic diseases. Betaine has been proven to play a role in improving glucose and lipid metabolism disorders in animal models. However, whether maternal betaine supplementation plays a role in regulating gut microbiota in both dams and offspring remains unclear. In this study, C57BL/6 female mice were fed with control diet (Ctr), high-fat diet (HF), and high-fat with betaine supplementation (0.3% betaine in the diet, HFB) from 3 weeks prior to mating and lasted throughout pregnancy and lactation. After weaning, the offspring got free access to normal chow diet until 20 weeks of age. We found that maternal dietary betaine supplementation significantly improved glucose and insulin resistance, as well as reduced free fatty acid (FFA) concentration in dams and offspring from young to adult. When compared to the HF group, Intestinimonas and Acetatifactor were reduced by betaine supplementation in dams; Desulfovibrio was reduced in 4-week-old offspring of the HFB group; and Lachnoclostridium was enriched in 20-week-old offspring of the HFB group. Moreover, the persistent elevated genus Romboutsia in both dams and offspring in the HFB group was reported for the first time. Overall, maternal betaine could dramatically alleviate the detrimental effects of maternal overnutrition on metabolism in both dams and offspring. The persistent alterations in gut microbiota might play critical roles in uncovering the intergenerational metabolic benefits of maternal betaine, which highlights evidence for combating generational metabolic diseases.

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