Clinical spectrum of late symptomatic neurosyphilis in China: an 11-year retrospective study.

OBJECTIVES: This study aimed to describe the clinical features of neurosyphilis in Chinese patients in an attempt to find clinical features that are helpful for the early identification of neurosyphilis. METHODS: This retrospective study included people with syphilis who visited Shanghai Skin Disease Hospital between January 2010 and December 2020. Lumbar puncture was performed on those who met the inclusion and exclusion criteria. The diagnosis of neurosyphilis was based on clinical and laboratory findings. The parameters were analysed statistically. RESULTS: Of the 3524 patients with neurosyphilis, 2111 (59.9%) and 1413 (40.1%) were asymptomatic and symptomatic neurosyphilis, respectively. General paresis was the most common type of symptomatic neurosyphilis (46.8%). The clinical manifestations of symptomatic neurosyphilis include psychiatric and neurotic symptoms, among which general paresis predominantly presented as psychiatric symptoms such as affective (66.7%) and memory disorder (72.9%). Tabes dorsalis is often presented as neurotic symptoms. One hundred fifty patients (10.6%) with symptomatic neurosyphilis presented candy signs, a rare and specific neurosyphilis symptom that is common in general paresis. Girdle sensation was presented in 13 patients, mainly with tabes dorsalis, which had not been reported in previous studies. CONCLUSIONS: Notably, the candy sign is identified as a specific symptom of general paresis, while girdle sensations are highlighted as a particular symptom of tabes dorsalis. This is the largest study describing the clinical spectrum of neurosyphilis since the onset of the penicillin era and could help doctors learn more about the disease. A comprehensive description of the possible clinical manifestations of late symptomatic neurosyphilis, particularly highlighting rare symptoms, can identify suspicious patients and prevent diagnostic delays.

Clinical parameter-based prediction model for neurosyphilis risk stratification.

Accurately predicting neurosyphilis prior to a lumbar puncture (LP) is critical for the prompt management of neurosyphilis. However, a valid and reliable model for this purpose is still lacking. This study aimed to develop a nomogram for the accurate identification of neurosyphilis in patients with syphilis. The training cohort included 9,504 syphilis patients who underwent initial neurosyphilis evaluation between 2009 and 2020, while the validation cohort comprised 526 patients whose data were prospectively collected from January 2021 to September 2021. Neurosyphilis was observed in 35.8% (3,400/9,504) of the training cohort and 37.6% (198/526) of the validation cohort. The nomogram incorporated factors such as age, male gender, neurological and psychiatric symptoms, serum RPR, a mucous plaque of the larynx and nose, a history of other STD infections, and co-diabetes. The model exhibited good performance with concordance indexes of 0.84 (95% CI, 0.83-0.85) and 0.82 (95% CI, 0.78-0.86) in the training and validation cohorts, respectively, along with well-fitted calibration curves. This study developed a precise nomogram to predict neurosyphilis risk in syphilis patients, with potential implications for early detection prior to an LP.

A novel transcription factor, ScAIL1, modulates plant defense responses by targeting DELLA and regulating gibberellin and jasmonic acid signaling in sugarcane.

DELLA proteins are important repressors of gibberellin signaling, regulating plant development and defense responses through crosstalk with various phytohormones. Sugarcane ScGAI encodes a DELLA protein that regulates culm development. However, it is unclear which transcription factors mediate the transcription of ScGAI. Here, we identified two different ScGAI promoter sequences that cooperatively regulate ScGAI transcription. We also identified a nuclear-localized AP2 family transcription factor, ScAIL1, which inhibits the transcription of ScGAI by directly binding to two ScGAI promoters. ScAIL1 was expressed in all sugarcane tissues tested and was induced by gibberellin and various stressors, including NaCl, polyethylene glycol, and pathogenic fungi and bacteria. Overexpression of ScAIL1 in rice significantly improved resistance to bacterial blight and rice blast, while reducing growth and development. In addition, several genes associated with stress responses were significantly up-regulated in transgenic rice overexpressing ScAIL1. Endogenous phytohormone content and expression analysis further revealed that ScAIL1-overexpressing lines improved resistance to bacterial blight and rice blast instead of promoting growth, and that this response was associated with increased jasmonic acid synthesis and gibberellin inactivation. These results provide molecular evidence that the role of ScAIL1 in the plant defense response is related to jasmonic acid and gibberellin signaling.

ScGAIL, a sugarcane N-terminal truncated DELLA-like protein, participates in gibberellin signaling in Arabidopsis.

The hormone gibberellin (GA) is crucial for internode elongation in sugarcane. DELLA proteins are critical negative regulators of the GA signaling pathway. ScGAI encodes a DELLA protein that was previously implicated in the regulation of sugarcane culm development. Here, we characterized ScGAI-like (ScGAIL) in sugarcane, which lacked the N-terminal region but was otherwise homologous to ScGAI. ScGAIL differed from ScGAI in its chromosomal location, expression patterns, and cellular localization. Although transgenic Arabidopsis overexpressing ScGAIL were insensitive to GAs, GA synthesis was affected in these plants, suggesting that ScGAIL disrupted the GA signaling pathway. After GA treatment, the expression patterns of GA-associated genes differed between ScGAIL-overexpressing and wild-type Arabidopsis, and the degradation of AtDELLA proteins in transgenic lines was significantly inhibited compared with wild-type lines. A sugarcane GID1 gene (ScGID1) encoding a putative GA receptor was isolated and interacted with ScGAIL in a GA-independent manner. Five ScGAIL-interacting proteins were verified by yeast two-hybrid assays, and only one interacted with ScGAI. Therefore, ScGAIL may inhibit plant growth by modulating the GA signaling pathway.

Genome-wide identification and expression analysis of AP2/ERF transcription factors in sugarcane (Saccharum spontaneum L.).

BACKGROUND: APETALA2/ETHYLENE RESPONSIVE FACTOR (AP2/ERF) transcription factors play essential roles in plant growth, development, metabolism, and responses to biotic and abiotic stresses. However, few studies concerning AP2/ERF genes in sugarcane which are the most critical sugar and energy crops worldwide. RESULTS: A total of 218 AP2/ERF genes were identified in the Saccharum spontaneum genome. Phylogenetic analysis showed that these genes could be divided into four groups, including 43 AP2s, 160 ERFs and Dehydration-responsive element-binding (DREB) factors, 11 ABI3/VPs (RAV), and four Soloist genes. These genes were unevenly distributed on 32 chromosomes. The structural analysis of SsAP2/ERF genes showed that 91 SsAP2/ERFs lacked introns. Sugarcane and sorghum had a collinear relationship between 168 SsAP2/ERF genes and sorghum AP2/ERF genes that reflected their similarity. Multiple cis-regulatory elements (CREs) present in the SsAP2/ERF promoter were related to abiotic stresses, suggesting that SsAP2/ERF activity could contribute to sugarcane adaptation to environmental changes. The tissue-specific analysis showed spatiotemporal expression of SsAP2/ERF in the stems and leaves of sugarcane at different development stages. In ten sugarcane samples, 39 SsAP2/ERFs were not expressed, whereas 58 SsAP2/ERFs were expressed in all samples. Quantitative PCR experiments showed that SsERF52 expression was up-regulated under salt stress, but suppressed under dehydration stress. SsSoloist4 had the most considerable upregulation in response to treatment with the exogenous hormones ABA and GA. Within 3 h of ABA or PEG6000 treatment, SsSoloist4 expression was up-regulated, indicating that this gene could play a role in the responses to ABA and GA-associated dehydration stress. Analysis of AP2/ERF gene expression patterns under different treatments indicated that SsAP2/ERF genes played an essential role in dehydration and salt stress responses of S. spontaneum. CONCLUSIONS: In this study, a total of 218 members of the AP2 / ERF superfamily were identified in sugarcane, and their genetic structure, evolution characteristics, and expression patterns were studied and analyzed. The results of this study provide a foundation for future analyses to elucidate the importance of AP2/ERF transcription factors in the function and molecular breeding of sugarcane.

Functional characterization of sugarcane ScFTIP1 reveals its role in Arabidopsis flowering.

The timing of floral transition is essential for reproductive success in flowering plants. In sugarcane, flowering time affects the production of sugar and biomass. Although the function of the crucial floral pathway integrators, FLOWERING LOCUS T (FT), in sugarcane, has been uncovered, the proteins responsible for FT export and the underlying mechanism remain unexplored. In this study, we identified a member of the multiple C2 domain and transmembrane region proteins (MCTPs) family in sugarcane, FT-interacting protein 1 (ScFTIP1), which was localized to the endoplasmic reticulum. Ectopic expression of ScFTIP1 in the Arabidopsis mutant ftip1-1 rescued the late-flowering phenotype. ScFTIP1 interacted with AtFT in vitro and in vivo assays. Additionally, ScFTIP1 interacted with ScFT1 and the floral inducer ScFT3. Furthermore, we found that the NAC member, ScNAC23, could directly bind to the ScFTIP1 promoter and negatively regulate its transcription. Overall, our findings revealed the function of ScFTIP1 and proposed a potential mechanism underlying flowering regulation in sugarcane.

Receptor-like cytoplasmic kinase ScRIPK in sugarcane regulates disease resistance and drought tolerance in Arabidopsis.

Introduction: Receptor-like cytoplastic kinases (RLCKs) are known in many plants to be involved in various processes of plant growth and development and regulate plant immunity to pathogen infection. Environmental stimuli such as pathogen infection and drought restrict the crop yield and interfere with plant growth. However, the function of RLCKs in sugarcane remains unclear. Methods and results: In this study, a member of the RLCK VII subfamily, ScRIPK, was identified in sugarcane based on sequence similarity to the rice and Arabidopsis RLCKs. ScRIPK was localized to the plasma membrane, as predicted, and the expression of ScRIPK was responsive to polyethylene glycol treatment and Fusarium sacchari infection. Overexpression of ScRIPK in Arabidopsis enhanced drought tolerance and disease susceptibility of seedlings. Moreover, the crystal structure of the ScRIPK kinase domain (ScRIPK KD) and the mutant proteins (ScRIPK-KD K124R and ScRIPK-KD S253A|T254A) were characterized in order to determine the activation mechanism. We also identified ScRIN4 as the interacting protein of ScRIPK. Discussion: Our work identified a RLCK in sugarcane, providing a potential target for sugarcane responses to disease infection and drought, and a structural basis for kinase activation mechanisms.

Interactions between ScNAC23 and ScGAI regulate GA-mediated flowering and senescence in sugarcane.

Control of gene transcription is crucial to regulate plant growth and development events, such as flowering, leaf senescence, and seed germination. Here we identified a NAC transcription factor (ScNAC23) isolated from sugarcane (cv. ROC22). Analysis by qRT-PCR indicated that ScNAC23 expression was strongly induced in mature leaves and flowering varieties and was also responsive to exogenous treatment with the hormone gibberellin (GA). Ectopic expression of ScNAC23 in Arabidopsis accelerated bolting, flowering, and leaf senescence compared to wild type plants. Furthermore, Arabidopsis overexpressed ScNAC23 were more sensitive to GA than the wild type, and exogenous GA significantly accelerated flowering and senescence in the ScNAC23-overexpressed ones. A direct interaction between ScNAC23 and ScGAI, an inhibitor of GA signaling, was confirmed by yeast-two hybrid, bimolecular fluorescence complementation, and GST-pull down assay. The putative GA-ScNAC23-LFY/SAGs regulator module might provide a new sight into the molecular action of GA to accelerating flowering and leaf senescence in sugarcane.

Dynamic recrystallization behavior and processing map of the Cu-Cr-Zr-Nd alloy.

Hot deformation behavior of the Cu-Cr-Zr-Nd alloy was studied by hot compressive tests in the temperature range of 650-950 °C and the strain rate range of 0.001-10 s(-1) using Gleeble-1500D thermo-mechanical simulator. The results showed that the flow stress is strongly dependent on the deformation temperature and the strain rate. With the increase of temperature or the decrease of strain rate, the flow stress significantly decreases. Hot activation energy of the alloy is about 404.84 kJ/mol and the constitutive equation of the alloy based on the hyperbolic-sine equation was established. Based on the dynamic material model, the processing map was established to optimize the deformation parameters. The optimal processing parameters for the Cu-Cr-Zr-Nd alloy hot working are in the temperature range of 900-950 °C and strain rate range of 0.1-1 s(-1). A full dynamic recrystallization structure with fine and homogeneous grain size can be obtained at optimal processing conditions. The microstructure of specimens deformed at different conditions was analyzed and connected with the processing map. The surface fracture was observed to identify instability conditions.