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1.
Int J Oral Maxillofac Implants ; 0(0): 1-20, 2024 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-39365911

RESUMEN

The development of a successful bone grafting technology with cohesive and adhesive properties has been an elusive goal for dental and orthopedic researchers. Tetracalcium phosphate combined with phosphoserine (TTCP-PS) is a synthetic, injectable, cohesive, self-setting, mineral-organic wet-field adhesive. The objective of this study was to evaluate four formulations of TTCP-PS in comparison to the conventional grafting materials, Bioglass and deproteinized cancellous bovine bone with a bioresorbable collagen membrane in standardized defects created in the angle of the rat mandible. Microcomputed tomography and histomorphometry were utilized to evaluate bone replacement with each of these materials after in vivo residence of either 4 or 12 weeks. The results of this study demonstrate that specific TTCP-PS formulations can form bone comparable to conventional materials in an osteopromotive mechanism but with the advantage of having cohesive and adhesive properties.

2.
Molecules ; 29(17)2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39274902

RESUMEN

Zinc cobalt oxide-zinc hydroxide (ZnCo2O4-Zn(OH)2) microspheres were successfully fabricated on carbon cloth via a sample hydrothermal method. The surface morphology of these microspheres and their efficacy in degrading methyl violet were further modulated by varying the thermal annealing temperatures. Adjusting the thermal annealing temperatures was crucial for controlling the porosity of the ZnCo2O4-Zn(OH)2 microspheres, enhancing their photocatalytic performance. Various analytical techniques were utilized to evaluate the physical and chemical properties of the ZnCo2O4-Zn(OH)2 microspheres, including field-emission scanning electron microscopy, energy-dispersive spectroscopy, X-ray diffraction, field-emission transmission electron microscopy, X-ray photoelectron spectroscopy, and UV-vis spectroscopy. Compared to untreated ZnCo2O4-Zn(OH)2 microspheres, those subjected to thermal annealing exhibited increased specific surface area and light absorption capacity, rendering them highly effective photocatalysts under UVC light exposure. Subsequent studies have confirmed the superior performance of ZnCo2O4-Zn(OH)2 microspheres as a reusable photocatalyst for degrading methyl violet and tetracycline. Furthermore, trapping experiments during the photodegradation process using ZnCo2O4-Zn(OH)2 microspheres identified hydroxyl radicals (·OH) and superoxide radicals (·O2⁻) as the primary reactive species.

5.
Cancers (Basel) ; 16(17)2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39272865

RESUMEN

Oligopulmonary metastases from primary liver tumors are typically treated surgically. We evaluated the clinical outcomes after lung metastasectomy in patients with pulmonary metastases from primary liver tumors. We retrospectively enrolled 147 consecutive patients with lung metastases from liver cancer who had undergone pulmonary metastasectomies at three medical centers between February 2007 and December 2020. All patients were pathologically confirmed to have lung metastases from liver cancer. Among the 147 patients, 110, 17, and 20 initially underwent surgical resection, radiofrequency ablation, and transcatheter arterial embolization, respectively. The 5-year overall survival (OS) in the study cohort was 22%. Univariate analysis revealed four factors associated with better OS: surgical resection as the initial primary liver tumor treatment (p = 0.004), a disease-free interval exceeding 12 months after the initial liver surgery (p = 0.036), a lower Model for End-Stage Liver Disease (MELD)-Na score (≤20) for liver cirrhosis (p = 0.044), and the absence of local liver tumor recurrence at the time of pulmonary metastasectomy (p = 0.004). Multivariate analysis demonstrated that surgical resection as the initial primary liver tumor treatment and lower MELD-Na scores significantly correlated with better OS. Our findings can assist thoracic surgeons in selecting suitable patients for surgery and predicting surgical outcomes.

6.
Artículo en Inglés | MEDLINE | ID: mdl-39190511

RESUMEN

Decoding natural language from noninvasive brain signals has been an exciting topic with the potential to expand the applications of brain-computer interface (BCI) systems. However, current methods face limitations in decoding sentences from electroencephalography (EEG) signals. Improving decoding performance requires the development of a more effective encoder for the EEG modality. Nonetheless, learning generalizable EEG representations remains a challenge due to the relatively small scale of existing EEG datasets. In this paper, we propose enhancing the EEG encoder to improve subsequent decoding performance. Specifically, we introduce the discrete Conformer encoder (D-Conformer) to transform EEG signals into discrete representations and bootstrap the learning process by imposing EEG-language alignment from the early training stage. The D-Conformer captures both local and global patterns from EEG signals and discretizes the EEG representation, making the representation more resilient to variations, while early-stage EEG-language alignment mitigates the limitations of small EEG datasets and facilitates the learning of the semantic representations from EEG signals. These enhancements result in improved EEG representations and decoding performance. We conducted extensive experiments and ablation studies to thoroughly evaluate the proposed method. Utilizing the D-Conformer encoder and bootstrapping training strategy, our approach demonstrates superior decoding performance across various tasks, including word-level, sentence-level, and sentiment-level decoding from EEG signals. Specifically, in word-level classification, we show that our encoding method produces more distinctive representations and higher classification performance compared to the EEG encoders from existing methods. At the sentence level, our model outperformed the baseline by 5.45%, achieving a BLEU-1 score of 42.31%. Furthermore, in sentiment classification, our model exceeded the baseline by 14%, achieving a sentiment classification accuracy of 69.3%.


Asunto(s)
Algoritmos , Interfaces Cerebro-Computador , Electroencefalografía , Procesamiento de Lenguaje Natural , Humanos , Electroencefalografía/métodos , Lenguaje , Semántica , Aprendizaje Automático Supervisado , Masculino , Femenino , Adulto , Reproducibilidad de los Resultados
8.
Am J Cancer Res ; 14(7): 3555-3564, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39113877

RESUMEN

This study aimed to evaluate the impact of different pre-transplant local treatments on the survival of liver transplantation (LTx) recipients with BCLC Stage A Hepatocellular Carcinoma (HCC). We analyzed data from the Taiwan Cancer Registry and National Health Insurance Research Databases spanning 2012 to 2018. Employing propensity score matching, patients were categorized into three groups: those receiving local treatments (180 patients), hepatectomy (179 patients), and combined treatments (180 patients). The primary outcomes were overall mortality and HCC-specific death, assessed using time-varying Cox regression models and Kaplan-Meier survival analysis. During a median follow-up period of 3.92 years, all-cause mortality rates were observed as 74.44% for local treatments, 42.46% for hepatectomy, and 65.00% for combined treatments. HCC-specific mortality rates followed a similar pattern at 65.00%, 39.11%, and 59.44%, respectively. Adjusted hazard ratios demonstrated significantly elevated mortality risks associated with local and combined treatments compared to hepatectomy. Notably, the 2-year overall and HCC-specific survival rates were highest in the hepatectomy group, surpassing those observed in both the combined treatment and local treatment groups. The findings of our study highlight that for patients with BCLC Stage A HCC, undergoing hepatectomy prior to LTx is associated with superior survival outcomes compared to solely local treatments. This underscores the importance of considering hepatectomy as a vital component of the treatment strategy in this patient population.

9.
J Crit Care Med (Targu Mures) ; 10(3): 209-212, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39108416

RESUMEN

Introduction: Current guidelines recommend limiting the rate of correction in patients with severe hyponatremia to avoid severe neurologic complications such as osmotic demyelination syndrome (ODS). However, published data have been conflicting. We aimed to evaluate the association between rapid sodium correction and ODS in patients with severe hyponatremia. Materials and methods: We searched PubMed, Embase, Scopus, Web of Science, and Cochrane Central Register of Controlled Trials from inception to November 2023. The primary outcome was ODS and the secondary outcomes were in-hospital mortality and length of hospital stay. Results: We identified 7 cohort studies involving 6,032 adult patients with severe hyponatremia. Twenty-nine patients developed ODS, resulting in an incidence rate of 0.48%. Seventeen patients (61%) had a rapid correction of serum sodium in the first or any 24-hour period of admission. Compared with a limited rate of sodium correction, a rapid rate of sodium correction was associated with an increased risk of ODS (RR, 3.91 [95% CI, 1.17 to 13.04]; I2 = 44.47%; p = 0.03). However, a rapid rate of sodium correction reduced the risk of in-hospital mortality by approximately 50% (RR, 0.51 [95% CI, 0.39 to 0.66]; I2 = 0.11%; p < 0.001) and the length of stay by 1.3 days (Mean difference, -1.32 [95% CI, -2.54 to -0.10]; I2 = 71.47%; p = 0.03). Conclusions: Rapid correction of serum sodium may increase the risk of ODS among patients hospitalized with severe hyponatremia. However, ODS may occur in patients regardless of the rate of serum sodium correction.

10.
J Neurooncol ; 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39167243

RESUMEN

BACKGROUND: Dendritic cell (DC) vaccine is an emerging immunotherapy that could potentially improve glioblastoma survival. The first phase III clinical trial of DC vaccine was recently published. This meta-analysis aims to update and reappraise existing evidence on the efficacy of DC vaccine in patients with glioblastoma. METHODS: We searched PubMed, Embase, and Cochrane Library for clinical trials of DC vaccine for glioblastoma. The quality of the studies was assessed using the RoB 2.0 and ROBINS-I tools. The results of overall survival (OS) and progression-free survival (PFS) were pooled using hazard ratios (HRs) with corresponding 95% confidence intervals (CI). Summary effects were evaluated using random effects models. Trial sequential analysis (TSA) was performed. RESULTS: Seven clinical trials involving 3,619 patients were included. DC vaccine plus standard care was associated with significantly improved OS (HR = 0.71; 95% CI, 0.57 - 0.88) and PFS (HR = 0.65; 95% CI, 0.43 - 0.98). In the subgroup of newly diagnosed glioblastoma, DC vaccine was associated with improved PFS (HR = 0.59; 95% CI, 0.39 - 0.90). TSA of OS showed that the cumulative z-score line for the DC vaccine crossed the benefit boundary and reached the required sample size. TSA of PFS and subgroup analysis of newly diagnosed glioblastoma showed that the required sample size was not reached. CONCLUSIONS: This updated meta-analysis, which included the first phase III trial of a DC vaccine for glioblastoma, demonstrated that the DC vaccine was associated with improved OS. Moreover, TSA showed that the required sample size was reached, indicating a true-positive result. Future studies are required for patient subgroups with newly diagnosed and recurrent glioblastoma.

11.
Urol Oncol ; 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39168785

RESUMEN

BACKGROUND: Nonmuscle invasive bladder cancer (NMIBC) has a favorable prognosis but has high propensity for recurrence. Recent development in one of the urinary biomarker tests, Bladder EpiCheck™, offers a noninvasive and accurate method to detect NMIBC recurrence. In this study, we aimed to compare the diagnostic performance of Bladder EpiCheck™ with urine cytology to detect NMIBC recurrence. METHODS: We performed a systematic review search through PubMed, Embase, Cochrane Central Register of Controlled Trials, Web of Science, and Scopus from inception to July 2023. Diagnostic accuracy was defined by sensitivity, negative predictive value (NPV), specificity, and positive predictive value (PPV). RESULTS: A total of 6 studies involving 1588 patients were included. Bladder EpiCheck™ has a sensitivity and specificity of 0.81 (95% CI: 0.63-0.91; I2: 43%) and 0.87 (95% CI: 0.83-0.91; I2: 20%), respectively. On the other hand, urine cytology has a sensitivity and specificity of 0.63 (95% CI: 0.29-0.87; I2: 61%) and 0.97 (95% CI: 0.78-1.00; I2: 79%), respectively. EpiCheck™ has a higher NPV (0.94 (95% CI: 0.87-0.97) vs. 0.84 (95% CI: 0.80-0.87) though a lower PPV (0.62 (95% CI: 0.45-0.76) vs. 0.87 (95% CI: 0.56-0.97) than urine cytology. In our subgroup analysis, the sensitivity of Bladder EpiCheck™ for detecting high-grade tumors improved to 0.90 (95% CI: 0.83-0.94) while that for urine cytology improved to 0.72 (95% CI: 0.50-0.87). CONCLUSION: Bladder EpiCheck™ has a high sensitivity and NPV for detecting recurrence among patients with NMIBC.

12.
PLoS One ; 19(8): e0309245, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39190688

RESUMEN

CD19-targeted chimeric antigen receptor (CAR) T cell therapies have driven a paradigm shift in the treatment of relapsed/refractory B-cell malignancies. However, >50% of CD19-CAR-T-treated patients experience progressive disease mainly due to antigen escape and low persistence. Clinical prognosis is heavily influenced by CAR-T cell function and systemic cytokine toxicities. Furthermore, it remains a challenge to efficiently, cost-effectively, and consistently manufacture clinically relevant numbers of virally engineered CAR-T cells. Using a highly efficient piggyBac transposon-based vector, Quantum pBac™ (qPB), we developed a virus-free cell-engineering system for development and production of multiplex CAR-T therapies. Here, we demonstrate in vitro and in vivo that consistent, robust and functional CD20/CD19 dual-targeted CAR-T stem cell memory (CAR-TSCM) cells can be efficiently produced for clinical application using qPB™. In particular, we showed that qPB™-manufactured CAR-T cells from cancer patients expanded efficiently, rapidly eradicated tumors, and can be safely controlled via an iCasp9 suicide gene-inducing drug. Therefore, the simplicity of manufacturing multiplex CAR-T cells using the qPB™ system has the potential to improve efficacy and broaden the accessibility of CAR-T therapies.


Asunto(s)
Antígenos CD19 , Antígenos CD20 , Inmunoterapia Adoptiva , Receptores Quiméricos de Antígenos , Antígenos CD19/inmunología , Humanos , Antígenos CD20/inmunología , Antígenos CD20/genética , Inmunoterapia Adoptiva/métodos , Receptores Quiméricos de Antígenos/inmunología , Receptores Quiméricos de Antígenos/genética , Animales , Ratones , Ingeniería Celular/métodos , Linfocitos T/inmunología , Línea Celular Tumoral
15.
Br J Haematol ; 205(2): 473-477, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38981737

RESUMEN

There are limited data on the optimal choice of anticoagulation in multiple myeloma (MM) patients receiving immunomodulatory drugs (IMiDs). We conducted a propensity score-matched cohort study using the TriNetX database to compare the efficacy and safety of factor Xa inhibitors and warfarin in this patient population. Compared to warfarin, factor Xa inhibitors had a similar risk of deep vein thrombosis (hazard ratio [HR]: 1.11 [95% CI: 0.50-2.46]) or pulmonary embolism (HR: 1.08 [95% CI: 0.59-2.00]). There were no differences in the risk of gastrointestinal or intracranial bleeding. Factor Xa inhibitor-treated patients had lower all-cause mortality (HR: 0.56 [95% CI: 0.36-0.86]) compared with warfarin. These data suggest that factor Xa inhibitors had similar safety and efficacy compared with warfarin for MM patients on IMiDs.


Asunto(s)
Anticoagulantes , Inhibidores del Factor Xa , Mieloma Múltiple , Warfarina , Humanos , Warfarina/uso terapéutico , Warfarina/efectos adversos , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/complicaciones , Mieloma Múltiple/mortalidad , Inhibidores del Factor Xa/uso terapéutico , Inhibidores del Factor Xa/efectos adversos , Femenino , Masculino , Anciano , Persona de Mediana Edad , Anticoagulantes/uso terapéutico , Anticoagulantes/efectos adversos , Trombosis de la Vena/prevención & control , Trombosis de la Vena/etiología , Agentes Inmunomoduladores/uso terapéutico , Agentes Inmunomoduladores/efectos adversos , Anciano de 80 o más Años , Embolia Pulmonar/prevención & control , Embolia Pulmonar/etiología
16.
Int J Mol Sci ; 25(11)2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38892282

RESUMEN

The rhizobacterial strain BJ3 showed 16S rDNA sequence similarity to species within the Burkholderia genus. Its complete genome sequence revealed a 97% match with Burkholderia contaminans and uncovered gene clusters essential for plant-growth-promoting traits (PGPTs). These clusters include genes responsible for producing indole acetic acid (IAA), osmolytes, non-ribosomal peptides (NRPS), volatile organic compounds (VOCs), siderophores, lipopolysaccharides, hydrolytic enzymes, and spermidine. Additionally, the genome contains genes for nitrogen fixation and phosphate solubilization, as well as a gene encoding 1-aminocyclopropane-1-carboxylate (ACC) deaminase. The treatment with BJ3 enhanced root architecture, boosted vegetative growth, and accelerated early flowering in Arabidopsis. Treated seedlings also showed increased lignin production and antioxidant capabilities, as well as notably increased tolerance to water deficit and high salinity. An RNA-seq transcriptome analysis indicated that BJ3 treatment significantly activated genes related to immunity induction, hormone signaling, and vegetative growth. It specifically activated genes involved in the production of auxin, ethylene, and salicylic acid (SA), as well as genes involved in the synthesis of defense compounds like glucosinolates, camalexin, and terpenoids. The expression of AP2/ERF transcription factors was markedly increased. These findings highlight BJ3's potential to produce various bioactive metabolites and its ability to activate auxin, ethylene, and SA signaling in Arabidopsis, positioning it as a new Burkholderia strain that could significantly improve plant growth, stress resilience, and immune function.


Asunto(s)
Arabidopsis , Burkholderia , Estrés Fisiológico , Burkholderia/genética , Burkholderia/metabolismo , Burkholderia/crecimiento & desarrollo , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Arabidopsis/microbiología , Estrés Fisiológico/genética , Desarrollo de la Planta/genética , Ácidos Indolacéticos/metabolismo , Regulación de la Expresión Génica de las Plantas , Genómica/métodos , Reguladores del Crecimiento de las Plantas/metabolismo , Raíces de Plantas/microbiología , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/genética , Raíces de Plantas/metabolismo , Etilenos/metabolismo
17.
Molecules ; 29(11)2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38893507

RESUMEN

The binary heterostructured semiconducting visible light photocatalyst of the iron-doped graphitic carbon nitride/bismuth molybdate (Fe-g-C3N4/Bi2MoO6) composite was prepared by coupling with Fe-doped g-C3N4 and Bi2MoO6 particles. In the present study, a comparison of structural characteristics, optical properties, and photocatalytic degradation efficiency and activity between Fe-doped g-C3N4 particles, Bi2MoO6 particles, and Fe-g-C3N4/Bi2MoO6 composite was investigated. The results of X-ray diffraction (XRD) examination indicate that the hydrothermal Bi2MoO6 particles have a single orthorhombic phase and Fourier transform infrared (FTIR) spectroscopy analysis confirms the formation of Fe-doped g-C3N4. The optical bandgaps of the Fe-doped g-C3N4 and Bi2MoO6 particles are 2.74 and 2.73 eV, respectively, as estimated from the Taut plots obtained from UV-Vis diffuse reflectance spectroscopy (DRS) spectra. This characteristic indicates that the two semiconductor materials are suitable for absorbing visible light. The transmission electron microscopy (TEM) micrograph reveals the formation of the heterojunction Fe-g-C3N4/Bi2MoO6 composite. The results of photocatalytic degradation revealed that the developed Fe-g-C3N4/Bi2MoO6 composite photocatalyst exhibited significantly better photodegradation performance than the other two single semiconductor photocatalysts. This property can be attributed to the heterostructured nanostructure, which could effectively prevent the recombination of photogenerated carriers (electron-hole pairs) and enhance photocatalytic activity. Furthermore, cycling test showed that the Fe-g-C3N4/Bi2MoO6 heterostructured photocatalyst exhibited good reproducibility and stability for organic dye photodegradation.

18.
Mol Med ; 30(1): 86, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38877399

RESUMEN

BACKGROUND: Despite the advances of therapies, multiple myeloma (MM) remains an incurable hematological cancer that most patients experience relapse. Tumor angiogenesis is strongly correlated with cancer relapse. Human leukocyte antigen G (HLA-G) has been known as a molecule to suppress angiogenesis. We aimed to investigate whether soluble HLA-G (sHLA-G) was involved in the relapse of MM. METHODS: We first investigated the dynamics of serum sHLA-G, vascular endothelial growth factor (VEGF) and interleukin 6 (IL-6) in 57 successfully treated MM patients undergoing remission and relapse. The interactions among these angiogenesis-related targets (sHLA-G, VEGF and IL-6) were examined in vitro. Their expression at different oxygen concentrations was investigated using a xenograft animal model by intra-bone marrow and skin grafts with myeloma cells. RESULTS: We found that HLA-G protein degradation augmented angiogenesis. Soluble HLA-G directly inhibited vasculature formation in vitro. Mechanistically, HLA-G expression was regulated by hypoxia-inducible factor-1α (HIF-1α) in MM cells under hypoxia. We thus developed two mouse models of myeloma xenografts in intra-bone marrow (BM) and underneath the skin, and found a strong correlation between HLA-G and HIF-1α expressions in hypoxic BM, but not in oxygenated tissues. Yet when stimulated with IL-6, both HLA-G and HIF-1α could be targeted to ubiquitin-mediated degradation via PARKIN. CONCLUSION: These results highlight the importance of sHLA-G in angiogenesis at different phases of multiple myeloma. The experimental evidence that sHLA-G as an angiogenesis suppressor in MM may be useful for future development of novel therapies to prevent relapse.


Asunto(s)
Antígenos HLA-G , Interleucina-6 , Mieloma Múltiple , Neovascularización Patológica , Mieloma Múltiple/sangre , Mieloma Múltiple/metabolismo , Mieloma Múltiple/patología , Humanos , Animales , Neovascularización Patológica/metabolismo , Antígenos HLA-G/sangre , Antígenos HLA-G/metabolismo , Ratones , Interleucina-6/sangre , Interleucina-6/metabolismo , Masculino , Femenino , Factor A de Crecimiento Endotelial Vascular/metabolismo , Factor A de Crecimiento Endotelial Vascular/sangre , Persona de Mediana Edad , Línea Celular Tumoral , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Anciano , Modelos Animales de Enfermedad , Angiogénesis
19.
Materials (Basel) ; 17(10)2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38793432

RESUMEN

This research successfully synthesized SnO2@ZnIn2S4 composites for photocatalytic tap water splitting using a rapid two-step microwave-assisted synthesis method. This study investigated the impact of incorporating a fixed quantity of SnO2 nanoparticles and combining them with various materials to form composites, aiming to enhance photocatalytic hydrogen production. Additionally, different weights of SnO2 nanoparticles were added to the ZnIn2S4 reaction precursor to prepare SnO2@ZnIn2S4 composites for photocatalytic hydrogen production. Notably, the photocatalytic efficiency of SnO2@ZnIn2S4 composites is substantially higher than that of pure SnO2 nanoparticles and ZnIn2S4 nanosheets: 17.9-fold and 6.3-fold, respectively. The enhancement is credited to the successful use of visible light and the facilitation of electron transfer across the heterojunction, leading to the efficient dissociation of electron-hole pairs. Additionally, evaluations of recyclability demonstrated the remarkable longevity of SnO2@ZnIn2S4 composites, maintaining high levels of photocatalytic hydrogen production over eight cycles without significant efficiency loss, indicating their impressive durability. This investigation presents a promising strategy for crafting and producing environmentally sustainable SnO2@ZnIn2S4 composites with prospective implementations in photocatalytic hydrogen generation.

20.
Plant Dis ; 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38783581

RESUMEN

Celosia spp. is a widely cultivated ornamental plant in gardens or parks in Taiwan. In September 2021, withering leaves and grayish-brown lesions were observed on the lower stem of plumed cockscombs (C. argentea var. plumosa) in Taichung City, with an incidence of about 22% in 136 plants after continuous precipitation, impacting the aesthetic value of the landscape. Symptomatic plants were collected, surface disinfected with 70% EtOH for ~20 sec., blotted dried, and excised diseased tissues (~ 3×3 mm2) were placed on 2% water agar. Four representative isolates were obtained after purification and the colonies were white with aerial and non-septated hyphae on V8 agar for 7 days. Sporangia were ovoid, ellipsoid or obpyriform, papillate, (26.3-55.9) 38.0 × 29.0 (20.1-40.6) µm (n = 200) (Ahonsi et al. 2007). Chlamydospores were spherical, terminal or intercalary, 26.0 (15.1-40.4) µm (n = 200). All isolates belong to A2 mating type with amphigynous antheridia and plerotic oospores, 21.0 (17.7-25.7) µm (n = 200), resembling the descriptions of Phytophthora (Erwin & Ribeiro 1996). For molecular identification, sequences of the ITS, ß-tubulin (ß-tub), and EF-1α regions of all isolates were amplified using ITS1/ITS4, TUBUF2/TUBUR1, and ELONGF1/ELONGR1 primers, respectively (White et al. 1990; Kroon et al. 2004). BLAST analyses of isolates cap1-2 (ITS: OQ581785; ß-tub: OQ590022; EF-1α: OQ590026), cap1-3 (ITS: OQ581786; ß-tub: OQ590023; EF-1α: OQ590027), cap2-1 (ITS: OQ581787; ß-tub: OQ590024; EF-1α: OQ590028), and cap2-2 (ITS: OQ581788; ß-tub: OQ590025; EF-1α: OQ590029) showed 100% of ITS identity, 99.5 to 99.9% of ß-tub identity, and 99.4 to 99.6% of EF-1α identity with Phytophthora nicotianae (ITS: MG865551; ß-tub: MH493987; EF-1α: MH359043). Phylogenetic trees were constructed using concatenated ITS, ß-tub, and EF-1α sequences based on maximum likelihood with a GTR+G model in MEGA X and Bayesian inference method in Geneious Prime 2022.2. All isolates were clustered in P. nicotianae with similar topology, thereby were identified as P. nicotianae. To confirm pathogenicity, 7 to 10-day-old seedlings and 6-week-old plumed cockscomb plants were inoculated in separate trials and each experiment was conducted twice. For each seedling, the lower stem was inoculated with 50 µl of zoospore suspension (104 zoospores/ml), 3 plants per isolate, and then incubated at 30±2℃ with 12 h light. For adult plants, each was inoculated with mycelial plugs from one V8 plate of 10-day-old P. nicotianae, 5 plants per isolate, and incubated at 25±2℃ in a greenhouse. Control plants were inoculated with sterile water and V8 agar plugs, respectively. Stem and root rot were observed on seedlings 4 days after inoculation while wilting and lower stem browning were observed on adult plants 2 months after inoculation. All control plants remained healthy at the end of repeated trials and identical pathogens were re-isolated only from symptomatic plants, thus fulfilling Koch's rules. P. nicotianae has been reported causing root rot and stem necrosis not only on cockscomb (C. plumosa Hort. ex Burvenich) in Argentina (Frezzi 1950), but also infecting several ornamental plants recently in Taiwan (Ann et al. 2018). To our knowledge, this is the first report of stem blight caused by P. nicotianae on plumed cockscombs in Taiwan. This finding suggests limited options for landscaping and the host preference of the isolates obtained in this study should warrant further studies.

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