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1.
Br J Radiol ; 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38781498

RESUMO

BACKGROUND: Prostate biopsies are mainly performed through transrectal or perineal approaches, while ultrasound probes are located in rectum for guidance. However, reports on the use of perineal ultrasound guided transperineal prostate biopsy (PG-TPPB) are few. METHODS: A retrospective case-control study was designed. A total of 111 patients who underwent PG-TPPB from February 2019 to December 2020 were investigated retrospectively. Simultaneously, 188 patients who underwent transrectal prostate biopsy (TRPB) were included as control. The prostate cancer detection rates (PCDR), complication rates, and application values were compared between the two groups. RESULTS: The overall PCDR in the PG-TPPB and TRPB groups were 33.3% (37/111) and 39.9% (75/188), respectively (P = 0.258). There was no significant difference in the PCDR between the two groups under each PSA level (all P > 0.05). The single-needle PCDR in the PG-TPPB and TRPB groups were 21.5%(277/1 287)and 24.0% (513/2 134), respectively (P = 0.091). The incidence of complications in the PG-TPPB group was significantly lower than that in the TRPB group (8.1% vs 21.3%, P = 0.003). CONCLUSIONS: The PCDRs of PG-TPPB and TRPB were the same. However, the postoperative complication rate of PG-TPPB was significantly lower than that of TRPB. Moreover, PG-TPPB required simpler equipment and did not require enema administration, which is suitable for patients with rectal contraindications. ADVANCES IN KNOWLEDGE: The reports on perineal ultrasound guided transperineal prostate biopsy (PG-TPPB) are few. Our study indicated PG-TPPB reduced the postoperative complication rate. Moreover, PG-TPPB required simpler equipment. Importantly, PG-TPPB is suitable for patients with rectal contraindications.

2.
BMC Cardiovasc Disord ; 24(1): 233, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38689231

RESUMO

OBJECTIVE: This study aimed to examine the changes in absolute value and decline rate of early serum cardiac troponin T (cTnT) and N-terminal pro b-type natriuretic peptide (NT-proBNP) in neonates who received veno-arterial (V-A) extracorporeal membrane oxygenation (ECMO) support therapy within the first week of life. METHODS: We retrospectively collected clinical data and laboratory test results of 18 neonates who underwent V-A ECMO support within one week of birth, from July 2021 to June 2023, using the electronic medical record system. These patients were categorized into survival and death groups. Comparative analyses of the absolute values and decline rates of cTnT and NT-proBNP were made between the groups at baseline, and at 24, 48, and 72 h post-ECMO initiation. RESULTS: Out of the 18 neonates, 12 survived (survival rate: 66.7%), while 6 succumbed. The survival group exhibited significantly lower absolute values of cTnT and NT-proBNP than the death group, and their decline rates were significantly higher. Notably, all neonates without an early decline in cTnT and NT-proBNP levels were in the death group. CONCLUSION: The early changes in the absolute value and decline rate of serum cTnT and NT-proBNP in neonates undergoing V-A ECMO may serve as predictors of their prognosis.


Assuntos
Biomarcadores , Oxigenação por Membrana Extracorpórea , Peptídeo Natriurético Encefálico , Fragmentos de Peptídeos , Troponina T , Humanos , Oxigenação por Membrana Extracorpórea/efeitos adversos , Oxigenação por Membrana Extracorpórea/mortalidade , Peptídeo Natriurético Encefálico/sangue , Troponina T/sangue , Recém-Nascido , Fragmentos de Peptídeos/sangue , Estudos Retrospectivos , Masculino , Feminino , Biomarcadores/sangue , Fatores de Tempo , Resultado do Tratamento , Valor Preditivo dos Testes , Fatores de Risco
3.
J Mater Chem B ; 12(17): 4270-4278, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38619420

RESUMO

Although the importance of circulating tumor cells (CTCs) has been widely recognized, it is still a challenge to realize high-efficiency and accurate enrichment and identification of highly heterogeneous CTCs derived from various types of tumors in complex cancer processes. Currently, the most widely used methods follow the general idea of sequential immunoaffinitive capture and immunostaining to achieve the abovementioned goal. However, different organ/tissue origins as well as the inherent heterogeneity of CTCs would lead to the missed detection of certain CTC subtypes using such methods. Further, immunocytochemistry (ICC) immunostaining disrupts the physiological structure of cells, severely limiting the detection and application scenarios that require the participation of live cells. To address these limitations, we have developed a generally applicable strategy for the isolation and labeling of CTCs. This strategy focuses on targeting the universal characteristics of all tumor cells, specifically the abnormally expressed cell membrane glycoproteins, such as the transferrin receptor and sialic acid. Strategically, transferrin-functionalized magnetic beads (TMBs) were applied to enrich CTCs, and azide-based bioorthogonal chemistry was employed to label target CTCs. Accordingly, the membrane glycoprotein-targeting strategy achieved unbiased enrichment and labeling of broad-spectrum CTCs that were both epithelial and non-epithelial phenotypic populations with varied organ/tissue origins (MCF-7, HepG2, A549, Jurkat, and B16), with a capture efficiency of >95% and a detection limit as low as 5 cells per mL in artificial blood. In particular, our developed strategy displayed excellent specificity, and the CTCs under capture and fluorescence labelling remained with good viability and could be further cultivated and analyzed. Finally, the membrane glycoprotein-targeting strategy successfully detected and identified 33-223 CTCs from 1 mL patient blood samples.


Assuntos
Células Neoplásicas Circulantes , Humanos , Células Neoplásicas Circulantes/patologia , Separação Celular/métodos , Glicoproteínas/química
4.
World J Gastrointest Endosc ; 16(2): 72-82, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38464816

RESUMO

BACKGROUND: Endoscopic submucosal dissection (ESD) and surgical resection are the standard of care for cT1N0M0 esophageal cancer (EC), whereas definitive chemoradiotherapy (d-CRT) is a treatment option. Nevertheless, the comparative efficiency and safety of ESD, surgery and d-CRT for cT1N0M0 EC remain unclear. AIM: To compare the efficiency and safety of ESD, surgery and d-CRT for cT1N0M0 EC. METHODS: We retrospectively analyzed the hospitalized data of a total of 472 consecutive patients with cT1N0M0 EC treated at Sun Yat-sen University Cancer center between 2017-2019 and followed up until October 30th, 2022. We analyzed demographic, medical recorded, histopathologic characteristics, imaging and endoscopic, and follow-up data. The Kaplan-Meier method and Cox proportional hazards modeling were used to analyze the difference of survival outcome by treatments. Inverse probability of treatment weighting (IPTW) was used to minimize potential confounding factors. RESULTS: We retrospectively analyzed patients who underwent ESD (n = 99) or surgery (n = 220) or d-CRT (n = 16) at the Sun Yat-sen University Cancer Center from 2017 to 2019. The median follow-up time for the ESD group, the surgery group, and the d-CRT group was 42.0 mo (95%CI: 35.0-60.2), 45.0 mo (95%CI: 34.0-61.75) and 32.5 mo (95%CI: 28.3-40.0), respectively. After adjusting for background factors using IPTW, the highest 3-year overall survival (OS) rate and 3-year recurrence-free survival (RFS) rate were observed in the ESD group (3-year OS: 99.7% and 94.7% and 79.1%; and 3-year RFS: 98.3%, 87.4% and 79.1%, in the ESD, surgical, and d-CRT groups, respectively). There was no difference of severe complications occurring between the three groups (P ≥ 0.05). Multivariate analysis showed that treatment method, histology and depth of infiltration were independently associated with OS and RFS. CONCLUSION: For cT1N0M0 EC, ESD had better long-term survival and lower hospitalization costs than those who underwent d-CRT and surgery, with a similar rate of severe complications occurring.

5.
Talanta ; 273: 125909, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38490020

RESUMO

The in vitro detection of circulating tumor cells (CTCs) has been proven as a vital method for early diagnosis and evaluation of cancer metastasis, since the existence and number fluctuation of CTCs have shown close correlation with clinical outcomes. However, it remains difficult and technically challenging to realize accurate CTCs detection, due to the rarity of CTCs in the blood samples with complex components. Herein, we reported a CTCs in vitro detection strategy, utilizing a loop amplification strategy based on DNA tetrahedron and nicking endonuclease reaction, as well as the anti-background interference based on lanthanide metal luminescence strategy. In this work, a detection system (ATDN-MLLPs) composed of an aptamer-functionalized tetrahedral DNA nanostructure (ATDN) and magnetic lanthanide luminescent particles (MLLPs) was developed. ATDN targeted the tumor cells via aptamer-antigen recognition and extended three hybridizable target DNA segments from the apex of a DNA tetrahedron to pair with probe DNA on MLLPs. Then, the nicking endonuclease (Nt.BbvCI) recognized the formed double-strand DNA and nicked the probe DNA to release the target DNA for recycling, and the released TbNps served as a high signal-to-noise ratio fluorescence signal source for CTCs detection. With a detection limit of 5 cells/mL, CTCs were selectively screened throughout a linear response range of low orders of magnitude. In addition, the ATDN-MLLPs system was attempted to detect possible existence of CTCs in biological samples in vitro.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Células Neoplásicas Circulantes , Humanos , Endonucleases/química , Luminescência , DNA/genética , DNA/química , Sondas de DNA/química , Metais , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Limite de Detecção , Técnicas de Amplificação de Ácido Nucleico/métodos
6.
Anal Bioanal Chem ; 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38363305

RESUMO

Nanozyme technology has gained significant regard and been successfully implemented in various applications including chemical sensing, bio-medicine, and environmental monitoring. Fe-CDs were synthesized and characterized well in this study. As compared to HRP (3.7 mM), the Fe-CDs exhibited a higher affinity towards H2O2 (0.2 mM) using the steady-state kinetic assay and stronger catalytic capability by changing the color of TMB to the blue color of the oxidized state, oxTMB. Additionally, an efficient peroxidase mimic, Fe-CDs/GOx, based on the hybrid cascade system to produce in situ H2O2 for the visual detection of glucose (color change: colorless to blue, and then to green), has been developed in detail, with limits of detection (LODs) for H2O2 and glucose of 0.33 µM and 1.17 µM, respectively. The changes further demonstrate a linear relationship between absorbance and H2O2 concentration, ranging from 10 to 60 µM, and for glucose (1 to 60 µM). To assess the accuracy and detection capability of the Fe-CDs/GOx system, we evaluated a real human serum sample obtained from adult males in a local hospital. In conclusion, Fe-CDs serving as a peroxidase mimic have the potential for various applications in the fields of biomedicine and nanozymes.

7.
Anal Chem ; 95(51): 18880-18888, 2023 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-38088834

RESUMO

Biocompatible fluorescent probes have emerged as essential tools in life sciences for visualizing subcellular structures and detecting specific analytes. Herein, we report the synthesis and characterization of a novel fluorescent probe (TPE-FdU), incorporated with hydrophilic 2'-fluoro-substituted deoxyuridine and hydrophobic ethynyl tetraphenylethene moieties, which possessed typical aggregation-induced emission (AIE) behavior. In comparison to the TPE-FdU (pKa 7.68) treated in neutral conditions, it performed well at pH 4, exhibiting an enhanced 450 nm emission signal of approximately four times stronger. As the pH value was increased to 10, the fluorescence intensity was completely quenched. The TEM images of TPE-FdU in an acidic environment (nanospherical morphology, AIE enhance, pH = 4) and in a basic environment (microrods, fluorescence quenching, pH = 9) revealed that it was a pH-dependent self-assembled probe, which was also illustrated by the interpretation of the NMR spectrum. Furthermore, the TPE-FdU probe exhibited a specific response to trace Hg2+ ions. Interestingly, the quenched fluorescence of the TPE-FdU probe caused by Hg2+ can be recovered by the addition of GSH due to the formation of the Hg-S bond being released away. MTT assay and CLSM images demonstrated that TPE-FdU was nontoxic and selectively visualized in the intracellular mitochondria. These results contributed to the development of advanced fluorescent probes with diverse applications in cell imaging, environment protection, and biomedical research.


Assuntos
Floxuridina , Corantes Fluorescentes , Corantes Fluorescentes/química , Mitocôndrias , Espectrometria de Fluorescência , Concentração de Íons de Hidrogênio
8.
Anal Chim Acta ; 1283: 341924, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37977773

RESUMO

A multifunctional nucleoside-based AIEgens sensor (TPEPy-dU) was constructed for visual screening of Hg2+, determine to the reversible response of Fe3+ and biothiols, and applied for cell imaging, and drug-free bacterial killing. The TPEPy-dU displayed 10-folds fluorescence enhancement at 540 nm of emission in response to trace Hg2+ ions with 10 nM of LOD, which can be immediately quenched by adding Fe3+ or GSH/Cys-containing sulfhydryl groups. Moreover, their bacterial staining efficiency closely correlates with their antibacterial efficacy as they demonstrated comparatively higher antibacterial activity against Gram-positive bacteria than Gram-negative bacteria. The drug-free antibacterial results involved the stating prominent surface damages at the sites of interactions between bacterial cells and TPEPy-dU that were further verified by CLSM and SEM images. It can be applied as a potential fluorescent agent to explore the related antibacterial mechanisms for treating and monitoring bacterial infections in vivo due to their nontoxic nature. Compared with conventional sensors and antibacterial therapies, these findings elevated the synthetic strategies of fluorescent probes and represented an advanced antibacterial agent wearing quaternary ammonium cationic with low resistance in clinical diagnosis.


Assuntos
Compostos de Amônio , Mercúrio , Nucleosídeos/farmacologia , Bactérias , Antibacterianos/farmacologia , Cátions , Mercúrio/farmacologia
9.
J Mater Chem B ; 11(43): 10288-10296, 2023 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-37886894

RESUMO

Noninvasive detection of small extracellular vesicles (sEVs) has become one of the most promising liquid biopsy methodologies for effective and timely cancer diagnosis and prognostic monitoring. Currently, accurate and sensitive detection of tumor-derived sEVs is compromised by their heterogeneous nature, and the tissue origin and parent cell cycle change may significantly affect the tumor-associated information (e.g., phenotypic proteins) of sEVs. Accordingly, many of the single-marker dependent detections on sEVs may not provide comprehensive information about the tumor, and their reliability and clinical applicability cannot be guaranteed. Herein, a strategy for constructing AND gate photoluminescence on tumor-derived sEVs is proposed. Briefly, only after co-recognition of the two epithelial phenotypic proteins (EpCAM and MUC1) on tumor-derived sEVs simultaneously, can our designed lanthanide luminescence probe precursors then assemble to form the AND gate for photoluminescence detection. Consequently, the generated AND gate photoluminescence provided time-resolved luminescence for a wide cancerous sEV linear detection range of 6.0 × 104-6.0 × 109 particles per mL, with a calculated detection limitation of 1.42 × 102 particles per mL. Furthermore, the AND gate photoluminescence can significantly distinguish epithelial cancer patients from healthy controls, displaying its great potential for accurate and noninvasive cancer diagnosis.


Assuntos
Vesículas Extracelulares , Elementos da Série dos Lantanídeos , Neoplasias , Humanos , Reprodutibilidade dos Testes , Ciclo Celular , Neoplasias/diagnóstico
10.
New Phytol ; 240(2): 815-829, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37533094

RESUMO

Bacteroid (name for rhizobia inside nodule cells) differentiation is a prerequisite for successful nitrogen-fixing symbiosis. In certain legumes, under the regulation of host proteins, for example, a large group of NCR (nodule cysteine rich) peptides, bacteroids undergo irreversible terminal differentiation. This process causes them to lose the ability to propagate inside nodule cells while boosting their competency for nitrogen fixation. How host cells maintain the viability of differentiated bacteroids while maximizing their nitrogen-reducing activities remains elusive. Here, through mutant screen, map-based cloning, and genetic complementation, we find that NCR343 is required for the viability of differentiated bacteroids. In Medicago truncatula debino1 mutant, differentiated bacteroids decay prematurely, and NCR343 is proved to be the casual gene for debino1. NCR343 is mainly expressed in the nodule fixation zone, where bacteroids are differentiated. In nodule cells, mature NCR343 peptide is secreted into the symbiosomes. RNA-Seq assay shows that many stress-responsive genes are significantly induced in debino1 bacteroids. Additionally, a group of stress response-related rhizobium proteins are identified as putative interacting partners of NCR343. In summary, our findings demonstrate that beyond promoting bacteroid differentiation, NCR peptides are also required in maintaining the viability of differentiated bacteroids.


Assuntos
Medicago truncatula , Rhizobium , Medicago truncatula/genética , Medicago truncatula/metabolismo , Peptídeos/metabolismo , Diferenciação Celular , Simbiose/fisiologia , Nitrogênio/metabolismo , Fixação de Nitrogênio/fisiologia , Nódulos Radiculares de Plantas/metabolismo
11.
J Fungi (Basel) ; 9(4)2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37108904

RESUMO

Phyllosticta spp. are important pathogens of citrus plants. Several Phyllosticta species associated with Citrus species grown in China have been reported; however, the relative prevalences of individual species and the distributions of their genotypes among host Citrus species remain largely unknown. In this study, we conducted an extensive survey of Phyllosticta species across 11 citrus-producing provinces in southern China. From fruits and leaves with black spots or black-spot-like symptoms, a total of 461 Phyllosticta strains were isolated. Based on molecular (ITS, actA, tef1, gapdh, LSU, and rpb2 sequences) and morphological data, the strains were systematically identified as belonging to five species: P. capitalensis, P. citrichinaensis, P. citriasiana, P. citricarpa, and P. paracitricarpa. To further understand intraspecific genetic diversity and relationships, strains of five species from different geographic and host sources were analyzed based on the multilocus sequence data. Our population genetic analyses revealed that all five Phyllosticta species on citrus showed evidence for clonal dispersals within and among geographic regions. In addition, pathogenicity tests using representative strains showed that all five species can cause disease on the tested Citrus spp. We discuss the implications of our results for the control and management of Citrus Black Spot and related diseases.

12.
World J Gastrointest Surg ; 14(9): 986-996, 2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36185565

RESUMO

BACKGROUND: Endoscopic ultrasonography (EUS) and magnifying endoscopy (ME) reliably determine indications for endoscopic resection in patients with superficial esophageal squamous cell carcinoma (SESCC). ME is widely accepted for predicting the invasion depth of superficial esophageal cancer with satisfying accuracy. However, the addition of EUS is controversial. AIM: To evaluate the diagnostic efficiency of ME vs EUS for invasion depth prediction and investigate the influencing factors in patients with SESCC to determine the best diagnostic model in China. METHODS: We retrospectively analyzed patients with suspected SESCC who completed both ME and EUS and then underwent endoscopic or surgical resection at Sun Yat-Sen University Cancer Center between January 2018 and December 2021. We evaluated and compared the diagnostic efficiency of EUS and ME according to histological results, and investigated the influencing factors. RESULTS: We included 152 lesions from 144 patients in this study. The diagnostic accuracies of ME and EUS in differentiating invasion depth were not significantly different (73.0% and 66.4%, P = 0.24); both demonstrated moderate consistency with the pathological results (ME: kappa = 0.58, 95% confidence interval [CI]: 0.48-0.68, P < 0.01; EUS: kappa = 0.46, 95%CI: 0.34-0.57, P < 0.01). ME was significantly more accurate in the diagnosis of high-grade intraepithelial (HGIN) or carcinoma in situ (odds ratio [OR] = 3.62, 95%CI: 1.43-9.16, P = 0.007) subgroups. Using a miniature probe rather than conventional EUS can improve the accuracy of lesion depth determination (82.3% vs 49.3%, P < 0.01). Less than a quarter of circumferential occupation and application of a miniature probe were independent risk factors for the accuracy of tumor invasion depth as assessed by EUS (< 1/4 circumferential occupation: OR = 3.07, 95%CI: 1.04-9.10; application of a miniature probe: OR = 5.28, 95%CI: 2.41-11.59, P < 0.01). Of the 41 lesions (41/152, 27.0%) that were misdiagnosed by ME, 24 were corrected by EUS (24/41, 58.5%). CONCLUSION: Preoperative diagnosis of SESCC should be conducted endoscopically using white light and magnification. In China, EUS can be added after obtaining patient consent. Use of a high-frequency miniature probe or miniature probe combined with conventional EUS is preferable.

13.
ACS Sens ; 7(10): 2833-2856, 2022 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-36112358

RESUMO

The G-quadruplex structure is crucial in several biological processes, including DNA replication, transcription, and genomic maintenance. G-quadruplex-based fluorescent probes have recently gained popularity because of their ease of use, low cost, excellent selectivity, and sensitivity. This review summarizes the latest applications of G-quadruplex structures as detectors of genome-wide, enantioselective catalysts, disease therapeutics, promising drug targets, and smart fluorescence probes. In every section, sensing of G-quadruplex and employing G4 for the detection of other analytes were introduced, respectively. Since the discovery of the G-quadruplex structure, several studies have been conducted to investigate its conformations, biological potential, stability, reactivity, selectivity for chemical modification, and optical properties. The formation mechanism and advancements for detecting different metal ions (Na+, K+, Ag+, Tl+, Cu+/Cu2+, Hg2+, and Pb2+) and biomolecules (AMP, ATP, DNA/RNA, microRNA, thrombin, T4 PNK, RNase H, ALP, CEA, lipocalin 1, and UDG) using fluorescent sensors based on G-quadruplex modification, such as dye labels, artificial nucleobase moieties, dye complexes, intercalating dyes, and bioconjugated nanomaterials (AgNCs, GO, QDs, CDs, and MOF) is described herein. To investigate these extremely efficient responsive agents for diagnostic and therapeutic applications in medicine, fluorescence sensors based on G-quadruplexes have also been employed as a quantitative visualization technique.


Assuntos
Quadruplex G , Ligantes , Corantes Fluorescentes/química , DNA/química , Íons
14.
J Oncol ; 2022: 2286040, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35646121

RESUMO

Currently, there is still controversy on postoperative adjuvant chemotherapy for node-negative advanced gastric cancer. Herein, we sought to evaluate the role of postoperative adjuvant chemotherapy in these patients. We retrospectively analyzed the clinical and pathological characteristics of 363 node-negative advanced gastric cancer patients in our hospital from 1996 to 2007 who underwent gastrectomy and D2 lymphadenectomy. We compared the survival rate of the surgery-only group with that of the adjuvant chemotherapy treatment group. The 5-year survival rates of patients in the surgery-only group and the chemotherapy treatment group were 70.7% and 73.8%, respectively. There was no significant difference in the survival rate between patients receiving postoperative chemotherapy and patients not receiving chemotherapy (P=0.328). However, postoperative chemotherapy treatment significantly increased the survival rate of pT4aN0M0 patients (P=0.020), although it did not exert a direct effect on the survival rate in pT2N0M0 and pT3N0M0 patients (P=0.990 and P=0.895). We also summarized and analyzed the side effects and safety of postoperative adjuvant chemotherapy. The rate of chemotherapy-related adverse events was 79.9%. Although 61 (36.1%) patients had to adjust their chemotherapy dose, no patient died from side effects. In conclusion, postoperative chemotherapy treatment is safe but did not show a direct impact on the survival rate of the node-negative advanced gastric cancer patients. However, pT4aN0M0 patients can benefit from postoperative adjuvant chemotherapy after undergoing D2 radical resections.

15.
J Fungi (Basel) ; 7(9)2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34575787

RESUMO

The fungal pathogen Diaporthe citri is a major cause of diseases in citrus. One common disease is melanose, responsible for large economic losses to the citrus fruit industry. However, very little is known about the epidemiology and genetic structure of D. citri. In this study, we analyzed 339 isolates from leaves and fruits with melanose symptoms from five provinces in southern China at 14 polymorphic simple sequence repeat (SSR) loci and the mating type idiomorphs. The genetic variations were analyzed at three levels with separate samples: among provinces, among orchards within one county, and among trees within one orchard. The five provincial populations from Fujian, Zhejiang, Jiangxi, Hunan, and Guizhou were significantly differentiated, while limited differences were found among orchards from the same county or among trees from the same orchard. STRUCTURE analysis detected two genetic clusters in the total sample, with different provincial subpopulations showing different frequencies of isolates in these two clusters. Mantel analysis showed significant positive correlation between genetic and geographic distances, consistent with geographic separation as a significant barrier to gene flow in D. citri in China. High levels of genetic diversity were found within individual subpopulations at all three spatial scales of analyses. Interestingly, most subpopulations at all three spatial scales had the two mating types in similar frequencies and with alleles at the 14 SSR loci not significantly different from linkage equilibrium. Indeed, strains with different mating types and different multilocus genotypes were frequently isolated from the same leaves and fruits. The results indicate that sexual reproduction plays an important role in natural populations of D. citri in southern China and that its ascospores likely represent an important contributor to citrus disease.

16.
Phytopathology ; 111(5): 779-783, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33315476

RESUMO

Melanose disease is one the most widely distributed and economically important fungal diseases of citrus worldwide. The causative agent is the filamentous fungus Diaporthe citri (syn. Phomopsis citri). Here, we report the genome assemblies of three strains of D. citri, namely strains ZJUD2, ZJUD14, and Q7, which were generated using a combination of PacBio Sequel long-read and Illumina paired-end sequencing data. The assembled genomes of D. citri ranged from 52.06 to 63.61 Mb in genome size, containing 15,977 to 16,622 protein-coding genes. We also sequenced and annotated the genome sequences of two citrus-related Diaporthe species, D. citriasiana and D. citrichinensis. In addition, a database for citrus-related Diaporthe genomes was established to provide a public platform to access genome sequences, genome annotation and comparative genomics data of these Diaporthe species. The described genome sequences and the citrus-related Diaporthe genomes database provide a useful resource for the study of fungal biology, pathogen-host interaction, molecular diagnostic marker development, and population genomic analyses of Diaporthe species. The database will be updated regularly when the genomes of newly isolated Diaporthe species are sequenced. The citrus-related Diaporthe genomes database is freely available for nonprofit use at zjudata.com/blast/diaporthe.php.


Assuntos
Citrus , Melanose , Ascomicetos , Genoma Bacteriano , Doenças das Plantas
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