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Given the prevalence of low-pathogenic but highly infectious Omicron variants, a cohort study was conducted to assess the response and duration of novel coronavirus-inactivated vaccine-induced antibodies 1 year after the third dose (Day 641). Blood samples were collected and anti-spike neutralizing antibodies (neutralizing antibody), total antibodies against the receptor-binding domain of the spike protein (total antibody), and immunoglobulin G antibodies against the spike protein (IgG antibody) were determined. Antibody kinetics and attenuation were evaluated. The results showed that the levels of neutralizing, total, and IgG antibodies on Day 641 were 98.05 IU/mL, 152.8 AU/mL, and 7.68 S/CO, respectively. Levels of anti-SARS-CoV-2 antibodies were higher in the younger subgroup than in the older subgroup at several time points after the second and third doses. The seropositive rate of neutralizing antibodies providing protection from infection or severe infection was 46.87% and 87.5%, and the seropositive rates of total antibody and IgG antibody were maintained at 100% and 90.63%, respectively. The half-lives of neutralizing, total, and IgG antibodies were 186.89, 363.04, and 417.50 days, respectively. Collectively, anti-SARS-CoV-2 antibodies may provide a certain degree of protection from infection 1 year after the third dose and high protection from severe infection.
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COVID-19 , Glicoproteína da Espícula de Coronavírus , Humanos , Estudos Prospectivos , Estudos de Coortes , Estudos Longitudinais , COVID-19/prevenção & controle , SARS-CoV-2 , Anticorpos Antivirais , Anticorpos Neutralizantes , Imunoglobulina GRESUMO
In this study, a halotolerant strain was isolated from high salinity leachate and identified as Bacillus cereus NT-3. It can produce a high concentration of polyhydroxyalkanoates (PHAs) with no significant changes when NaCl concentration is up to 50 g/L. FTIR and NMR spectra of PHAs synthesized by Bacillus cereus NT-3 were similar to the standard or previous results. Effluent from acidogenic fermentation of food waste and pure volatile fatty acids (VFAs) mixture was used as carbon source to check the effect of non-VFAs compounds of the effluent on PHAs production. The maximum PHAs production was 0.42 g/L for effluent fermentation, whereas it was 0.34 g/L for pure VFAs fermentation, indicating that bacteria could use actual effluent in a better way. Furthermore, a mathematical model was established for describing kinetic behavior of bacteria using different carbon sources. These results provided a promising approach for PHAs biosynthesis with a low-cost carbon source.
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Bacillus cereus/metabolismo , Carbono/metabolismo , Ácidos Graxos Voláteis/metabolismo , Poli-Hidroxialcanoatos/biossíntese , Eliminação de Resíduos , Bacillus cereus/isolamento & purificação , Ácidos Graxos Voláteis/química , FermentaçãoRESUMO
Objective: To assess the efficacy and safety of colistin sulfate in treating infections caused by carbapenem-resistant organisms (CRO) and to analyze potential factors impacting its effectiveness. Methods: In this retrospective study, medical records of CRO-infected patients from June 2020 to June 2023 were analyzed, divided into effective and ineffective treatment groups, and compared for clinical outcomes and adverse reactions. Multifactorial logistic regression and ROC curve analysis were used to identify influencing factors. Results: The study included 226 patients, with 124 in the effective treatment group and 102 in the ineffective group. A total of 293 CRO strains were cultured. The clinical efficacy rate of colistin sulfate was 54.87%, the microbiological efficacy rate 46.46%, and the hospital mortality rate 20.80%, with nephrotoxicity observed in 11.50% of patients. Multifactorial analysis identified APACHE II scores and vasoactive drug use as independent predictors of ineffective treatment, while treatment duration and albumin levels predicted effective treatment. ROC analysis indicated that albumin levels >34 g/L, APACHE II scores <13, and treatment duration >10 days correlated with better clinical efficacy. Conclusion: Colistin sulfate is both safe and effective in clinical settings. Factors such as treatment duration, albumin levels, APACHE II scores, and vasoactive drug use independently affect its clinical efficacy, providing valuable guidance for its informed clinical application.
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Syphilis has resurged in many countries, which has called attention to vaccine development. Based on the immunization-based rabbit model of infection with the Nichols strain, this study explored the protective immune response of a controversial syphilis vaccine candidate, TprK, and found that immunization with full-length rTprK was effective in attenuating lesion development and accelerating lesion resolution, which could reduce the probability of the pathogen spreading to distant tissue sites to prevent the progression of the disease to some extent. Furthermore, the results revealed that immunization with rTprK not only rapidly induced a strong Th1-like cellular response but also elicited a humoral immune response to produce opsonic antibodies to enhance macrophage-mediated opsonophagocytosis. Although complete protection against infection was not achieved, the study provided a comprehensive and in-depth exploration of the immunogenicity of TprK and highlighted the importance of TprK as a promising syphilis vaccine component.
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Interleukin-6 (IL-6) is a multi-effective cytokine involved in multiple immune responses. Whether fibroblasts also turn out to be a cytokine IL-6 factory during interaction with Treponema pallidum is not yet understood. To explore whether fibroblasts participate in inflammation due to syphilis, a series of experiments were performed to explore the role of T. pallidum lipoprotein Tp47 in IL-6 production in human dermal fibroblasts. The Toll-like receptor 2 (TLR2) and participating signalling pathways in this process were also evaluated. The results showed that the expressions of IL-6 and the protein levels of TLR2 in fibroblasts were upregulated after stimulation with Tp47, and this effect was impeded by the TLR2 inhibitor C29. In addition, Tp47 promoted the phosphorylation of p38, PI3K/Akt, and nuclear factor-kappaB (NF-κB), and the translocation of NF-κB in fibroblasts. Moreover, p38, PI3K, and NF-κB inhibitors significantly reduced IL-6 production in fibroblasts stimulated with Tp47. Furthermore, the TLR2 inhibitor C29 inhibited the phosphorylation of p38, Akt, and NF-κB, and the translocation of NF-κB in fibroblasts. In conclusion, our results showed that Tp47 enhanced IL-6 secretion in human dermal fibroblasts through TLR2 via p38, PI3K/Akt, and NF-κB signalling pathways. These findings contribute to our understanding of syphilis inflammation.
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NF-kappa B , Sífilis , Humanos , NF-kappa B/metabolismo , Interleucina-6/metabolismo , Treponema pallidum/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor 2 Toll-Like/genética , Receptor 2 Toll-Like/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Sífilis/metabolismo , Citocinas/metabolismo , Inflamação , Proteínas Recombinantes/metabolismo , Fibroblastos/metabolismoRESUMO
Heterogeneous tprK sequences have been hypothesized to be an important factor for persistent infection of Treponema pallidum subsp. pallidum (T. pallidum) in humans. Previous research has only explored tprK diversity using a rabbit model infected with almost clonal isolates, which is inconsistent with the fact that infected human isolates contain multiple heterogeneous tprK sequences. Here, we used the T. pallidum Amoy strain with heterogeneous tprK sequences to establish a rabbit infection model and explore longitudinal variations in the tprK gene under normal infection, immunosuppression treatment, and benzathine penicillin G (BPG) treatment using next-generation sequencing. The diversity of the tprK gene was high in all three groups but was highest in the control group and lowest in the BPG group. Interestingly, the overall diversity of tprK in all three groups decreased during infection, exhibiting a "more to less" trend, indicating that survival selection may be an important factor affecting tprK variation in the later infection stage. BPG treatment appeared to reduce the diversity of tprK but increased the frequency of predominant sequence changes, which might facilitate the escape of T. pallidum from the host immune clearance. Furthermore, the original predominant V region sequence did not disappear with disease progression but retained a relatively high proportion within the population, suggesting a new direction for tprK-related vaccine research. This study provides insights into longitudinal variations within the highly heterogeneous tprK gene sequences of T. pallidum and will contribute to further exploration of the pathogenesis of syphilis. IMPORTANCE The tprK variations are an important factor in persistent T. pallidum infection. A nearly clonal isolate has been used previously to investigate the mechanism of tprK gene variations; however, clinical T. pallidum isolates in infected humans exhibit multiple heterogeneous tprK sequences. Here, we use next-generation sequencing to explore longitudinal variations in the tprK gene under normal infection and immunosuppression and benzathine penicillin G treatment in a rabbit model infected with the Amoy strain with heterogeneous tprK sequences. The overall diversity of tprK in all three groups was high and decreased during infection, exhibiting a "more to less" trend. Benzathine penicillin G treatment reduced the diversity of tprK but increased the frequency of predominant sequence changes. Moreover, the original predominant V region sequence did not disappear as the disease progressed but remained at a relatively high proportion within the population. The research results give us a new understanding about tprK variation.
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Sífilis , Treponema pallidum , Animais , Coelhos , Humanos , Treponema pallidum/genética , Penicilina G Benzatina , Treponema/genética , Infecção PersistenteRESUMO
PCR can be a supplement to Treponema serological testing. However, its sensitivity is not satisfactory for blood sample testing. The aim of this study was to investigate whether pretreatment with red blood cell (RBC) lysis could enhance the yield of Treponema pallidum subsp. pallidum DNA extraction from blood. We developed and verified the efficacy of a quantitative PCR (qPCR) assay that utilizes TaqMan technology to specifically detect T. pallidum DNA by targeting the polA gene. Simulation media with 106 to 100 treponemes/mL were prepared in normal saline (NS), whole blood, plasma, and serum, and RBC lysis pretreatment was performed on a portion of whole blood. Then, blood samples drawn from 50 syphilitic rabbits were divided in parallel into five groups, labeled whole blood, whole blood/lysed RBCs, plasma, serum, and blood cells/lysed RBCs. DNA extraction and qPCR detection were performed. The detection rate and copy number were compared among different groups. The polA assay showed good linearity and an excellent amplification efficiency of 102%. In the simulated blood samples, the detection limit of the polA assay reached 1 × 102 treponemes/mL in whole blood/lysed RBCs, plasma, and serum. However, the detection limit was only 1 × 104 treponemes/mL in NS and whole blood. Among the blood samples from syphilitic rabbits, whole blood/lysed RBCs showed the best detection rate (82.0%), while the detection rate for whole blood was only 6%. The copy number of whole blood/lysed RBCs was higher than that of whole blood. RBC lysis pretreatment can significantly improve the yield of T. pallidum DNA from whole blood, and the yield is better than that from whole blood, plasma, serum, and blood cells/lysed RBCs. IMPORTANCE Syphilis is a sexually transmitted disease caused by T. pallidum that can spread into the blood. T. pallidum DNA can be detected in blood by PCR but with low sensitivity. Few studies have applied RBC lysis pretreatment to blood T. pallidum DNA extraction. This study shows that the detection limit, detection rate, and copy number of whole blood/lysed RBCs were better than those of whole blood, plasma, and serum. After RBC lysis pretreatment, the yield of low concentrations of T. pallidum DNA was improved, and the low sensitivity of blood-based T. pallidum PCR was improved. Therefore, whole blood/lysed RBCs are the ideal sample for acquiring blood T. pallidum DNA.
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Sífilis , Treponema pallidum , Animais , Coelhos , Treponema pallidum/genética , Sífilis/diagnóstico , Plasma , Soro , EritrócitosRESUMO
M2 macrophages were related to local immune homeostasis and maternal-fetal tolerance in normal pregnancy; whether M2 macrophages can respond to the stimulation of Treponema pallidum to mediate placental vascular inflammation injury is unclear. In this study, M2 macrophages were constructed to investigate the impact of T. pallidum on macrophage polarization and the underlying signaling pathway involved in this process, and the influence of macrophage polarization triggered by T. pallidum on the apoptosis and angiogenesis of human umbilical vein endothelial cells (HUVEC) was also explored. The results showed that M2 macrophage markers (CD206 and PPARγ) and anti-inflammatory factors (TGFß and CCL18) were decreased, while M1 macrophage marker CD80 and inflammatory cytokines (IL1ß and TNFα) were increased when M2 macrophages were treated with T. pallidum, indicating that T. pallidum promoted the polarization of M2 subtype macrophages to the M1 subtype. Moreover, T. pallidum-induced M1 macrophage polarization was found to be significantly correlated with the activation of Janus kinase 1 (JAK1) and signal transducer and activator of transcription 1 (STAT1). In addition, T. pallidum-induced M1 macrophages were found to promote apoptosis and inhibit the angiogenesis of HUVECs, and JAK1 or STAT1 inhibitors could weaken the apoptosis rate and promote the angiogenesis of HUVECs. These findings revealed that T. pallidum promoted the polarization of M2 macrophages to the M1 subtype through the JAK1-STAT1 signal pathway mediating the apoptosis and inhibiting angiogenesis of HUVECs, which may provide a possible mechanism for T. pallidum-induced adverse pregnancy outcomes.
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Angiogênese , Treponema pallidum , Humanos , Feminino , Gravidez , Células Endoteliais da Veia Umbilical Humana , Placenta , Macrófagos/metabolismo , ApoptoseRESUMO
In this paper, novel micro-architectures with X-type lattice unit cell (namely, face-centered cubic (FCC), and X-type) are constructed and prepared by additive manufacturing technology. The compression behaviors of micro-architectures are explored in detail by experimental measurement and theoretical prediction. It is found that the strength of FCC micro-lattice structure is higher than that of the X-type micro-lattice structure with the same relative density. The X-type micro-lattice structure exhibits a zero Poisson's ratio during compression deformation. In addition, the compressive strength and energy absorption efficiency of proposed micro-architectures shows a higher advantage over other previously cellular materials in a map for material selection.
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Real-time reverse transcription-polymerase chain reaction (RT-PCR) is the gold standard for diagnosing coronavirus disease 2019 (COVID-19). However, RT-PCR may yield false-positive results, leading to unnecessary countermeasures. Here, we report a "positive" nucleic acid test on a 10-pooled sample during the routine screening that caused many adverse societal effects, and financial and resource losses. However, they were subsequently determined to be a case of vaccine contamination. This case study increases awareness of false-positive RT-PCR results for SARS-CoV-2, especially when participants are vaccinators. Moreover, it could provide relevant suggestions to prevent the recurrence of such incidents.
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Background: Chancre self-healing, a typical clinical phenomenon of primary syphilis, is essentially wound healing. The first response to a wound is constriction of the injured blood vessels and activation of platelets to form a fibrin clot. However, the role of Treponema pallidum in platelet activation and clot formation remains unclear. Objectives: We aimed to elucidate the role of the outer membrane Treponema pallidum lipoprotein Tp0136 in human platelet activation and aggregation and explore the related mechanism. Methods: A series of experiments were performed to assess the effects of Tp0136 on human platelet activation and aggregation in vitro. The effect of Tp0136 on platelet receptors was studied by detecting PAR1 protein levels and studying related receptor sites. The involvement of the Gq/Gi signaling pathway downstream of PAR1 was explored. Results: Tp0136 significantly accelerated the formation of human platelet clots as well as platelet adhesion to and diffusion on fibrinogen to promote platelet aggregation. Tp0136 also potentiated P-selectin expression and PF4 release to promote platelet activation and downregulated PAR1 expression. The activation and aggregation induced by Tp0136 were reverted by the specific PAR1 antagonist RWJ56110 and the human PAR1 antibody. In addition, Tp0136 significantly enhanced Gq and Gi signaling activation, thereby triggering p38 phosphorylation and Akt-PI3K activation, increasing the release of intraplatelet Ca2+ and attenuating the release of cytosolic cAMP. Furthermore, the specific PAR1 antagonist RWJ56110 significantly suppressed Gq and Gi signaling activation. Conclusions: Our results showed that the Treponema pallidum Tp0136 protein stimulated human platelet activation and aggregation by downregulating PAR1 and triggered PAR1-dependent Gq and Gi pathway activation. These findings may contribute to our understanding of the self-healing of chancroid in early syphilis.
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Receptor PAR-1 , Sífilis , Humanos , Lipoproteínas/metabolismo , Ativação Plaquetária , Agregação Plaquetária , Receptor PAR-1/metabolismo , Transdução de Sinais , Treponema pallidumRESUMO
To evaluate the application of cycle threshold (Ct) values of coronavirus disease 2019 (COVID-19) patients in predicting epidemic dynamics and monitoring surface contamination. The Ct value of reverse transcriptase-polymerase chain reaction for SARSCoV-2 from COVID-19 patients inbound overseas in Xiamen, China was collected from October 2020 to December 2021, and the correlation of patients' Ct values with epidemic dynamics and surface contamination was evaluated. The results showed that there was an extreme inverse correlation of positivity rate in the current calendar month (ORF1ab, r = -0.692, P = 0.004; N,r = -0.629, P = 0.012) and the following calendar month (ORF1ab,r = -0.801, P = 0.001; N,r = -0.620, P = 0.018) with the median Ct values. Ct value showed better performance for monitoring surface contamination, with the area under the curve value 0.808(95 %CI: 0.748-0.869) for ORF1ab and 0.807(95 %CI:0.746-0.868) for the N gene. The patients' ORF1ab Ct value< 29.09 or N Ct value< 28.03 were 11.25 times and 10.48 times more likely to result in surface contamination than those with ORF1ab Ct value ≥ 29.09 or N Ct value≥ 28.03 (OR:11.25,95 % CI: 5.52-22.35; OR:10.48,95 % CI:5.29-20.70). Ct values were associated with the positivity rate in the current or following calendar month and predicted the epidemic dynamics. The Ct values can be used as a predictor for monitoring surface contamination to develop public health responses to COVID-19.
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COVID-19 , Epidemias , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Saúde PúblicaRESUMO
BACKGROUND: Determining what quarantine period and detection strategy are more effective and sustainable remains a challenge for further prevention and social stability. METHODS: From October 2020 to December 2021, 290,547 inbound overseas travelers were subject to government quarantine in Xiamen, China. The detection rate of COVID-19 during different quarantine periods using dual or single nucleic acid testing reagents. RESULTS: The COVID-19 positive rate was 1.79% (519/290,547). The detection rates during the 7-day, 14-day and 14+7-day quarantine periods using the dual reagents were 78.4%, 91.7%, and 100%, respectively. The detection rate of the 7-day, 14-day and 14+7-day quarantine periods were 73.99%, 86.51%, and 94.22%, respectively, using the Liferiver reagent and 72.25%, 84.59%, and 91.91%, respectively, using the Daan reagent. Based on the 14+7 day strategy, dual nucleic acid testing reagent strategy detected all imported cases, but 30 cases (5.78%) were not detected via Liferiver reagent and 42 (8.09%) cases not detected via Daan reagent. CONCLUSION: A 14+7-day quarantine period and dual nucleic acid testing reagent strategy are effective screening methods for COVID-19 among inbound overseas travelers. The superior detection rate of these strategies reduce the risk of secondary transmission of the SARS-CoV-2 virus.
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COVID-19 , Ácidos Nucleicos , COVID-19/diagnóstico , China , Humanos , Indicadores e Reagentes , Quarentena , SARS-CoV-2RESUMO
CONTEXT.: Neutralizing antibody detection can assess the incidence of COVID-19 and the effectiveness of vaccines. However, commercial reagents for neutralizing antibodies were developed after the anti-SARS-CoV-2 immunoglobulin (Ig) G and IgM antibodies. Therefore, some laboratories did not perform neutralizing antibody testing services because of multiple factors. OBJECTIVE.: To find a fast, accurate, and economic alternative for the detection of neutralizing antibodies for the development of COVID-19 screening programs. DESIGN.: The response and correlation of 3 antibodies (anti-spike protein neutralizing antibody, total anti-receptor-binding domain [RBD] antibody, and anti-RBD IgG) were determined by observing the dynamics in 61 participants for 160 days after vaccination. RESULTS.: The levels of neutralizing and anti-RBD IgG antibodies reached their peak values on day 42 after vaccination (120.75 IU/mL and 14.38 signal-to-cutoff ratio [S/CO], respectively). The total antibody levels peaked at 138.47 S/CO on day 35 after vaccination. The strongest correlation was found between neutralizing and anti-RBD IgG antibody levels (r = 0.894, P < .001). The area under the receiver operating characteristic curve for total antibody levels for the prediction of seropositivity for neutralizing antibodies was 0.881 (P < .001), and that for anti-RBD IgG antibody levels was 0.937 (P < .001). CONCLUSIONS.: Neutralizing and anti-RBD IgG antibody levels were strongly correlated, and thus anti-RBD IgG antibody levels can be used for the accurate assessment of immunity following SARS-CoV-2 infection or vaccination.
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COVID-19 , Imunoglobulina G , Glicoproteína da Espícula de Coronavírus , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/diagnóstico , COVID-19/imunologia , Humanos , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/químicaRESUMO
The compound Bi(cys)(3).H(2)O (cys=L-cysteine) has been obtained from the displacement reaction of [Bi(cit)](-) (cit=citrate) with cys in aqueous solution, and characterized by X-ray crystallography for the first time. It crystallizes in orthorhombic system with the space group P2(1)2(1)2(1), a=5.135(3)A, b=11.841(7)A, c=28.120(16)A, V=1709.8(17)A(3). The displacement reaction between bismuth citrate with cysteine in aqueous solution has been found to be pH-dependent and the complete displacement of the bound citrate with cysteine occurs at physiological pH value.
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Cisteína/química , Concentração de Íons de Hidrogênio , Cristalografia por Raios X , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Espectrofotometria UltravioletaRESUMO
A pilot-scale study with conventional water treatment and ozone-biological activated carbon (O3-BAC) treatment was conducted to evaluate the impact of ammonia and hydrogen peroxide (H2O2) addition on the bromate and disinfection by-products formation potential (DBPFP) control, with bromide containing water as raw water. It was found that bromate concentration would exceed 10.00 µg·L-1 as ozone doses were higher than 1.0 mg·L-1 under different water qualities. Ammonia and H2O2could effectively control bromate formation and bromate concentration decreased as ammonia and H2O2 doses increased. Bromate concentration could be controlled below 10.00 µg·L-1 as ammonia dose was 0.10-0.30 mg·L-1 or the m(H2O2)/m(O3) was 0.2-1.0. However, as ammonia-H2O2 was combined for the same purpose, bromate increased firstly and then decreased. Ammonia addition would not significantly affect the THMFP control but H2O2 application would depress the efficiency of THMFP removal.
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Soil salinization and overgrazing are two main factors limiting animal husbandry in the Songnen Grassland. Leymus chinensis is a dominant rhizome grass, resistant to grazing as well as to-lerant to salt stress. Foliar labeled with 15N-urea was used to study the nitrogen allocation strategy and compensatory growth response to clipping under saline-alkali conditions. The results showed that the total absorbed 15N allocated to the aboveground part was more than 60%. Compared with the control treatment (no saline-alkali, no clipping), saline-alkali increased the distribution of 15N by 5.1% in root; the 15N distribution into aboveground in the moderate clipping and saline-alkali treatment was 11.6% higher than that of the control, exhibiting over-compensatory growth of aboveground biomass and total biomass, however, 15N allocated to stem base was significantly increased by 9.5% under severe clipping level and saline-alkali addition, showing under-compensatory growth of shoot, root and total biomass. These results suggested that L. chinensis adapted to mode-rate clipping by over-compensatory growth under salt-alkali stress condition. However, L. chinensis would take a relatively conservative growth strategy through the enhanced N allocation to stem base for storage under severe saline-alkali and clipping conditions.
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Nitrogênio , Poaceae , Álcalis , Animais , Biomassa , SoloRESUMO
Two Bi (III) contained heteropolymate compounds Cos [Bi2 Co2 W20 O70 (H2O)6] x 44H2O (I)and Na3 H2 [Ce3 (H2O)18 Bi2 W22 O76] x 23H2O (II) have been synthesized under hydrothermal condition. The relationship between their properties and structures was studied by using FTIR, NIR FT-Raman, and UV-Vis DRS etc. The characteristic vibrational frequencies nu(as) (M = O(d)) and nu(s) (M-O(b)-M) is related to the structure of the materials. Nu(as) (M-O(b)-M) is demonstrated to explain why the the oxidative ability becomes stronger when W atoms are substituted by Co atoms. In UV-Vis DRS spectra of compound I and II, there are two characteristic peaks at 254, 319 nm and 220, 310 nm coresponding O(d) --> W and to O(b), c --> W charge transfer, respectively. The wide and weak absorption band of compound I at 529 nm can be assigned as Co2+ d-d transfer. Finally, quantum chemistry calculation of compound I was performed to explain the structure characteristic.
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Four novel polyoxovanadium borates with [(VO)12O6B18O42], namely (enH2)6 H3 [(VO)12O6B18O42].13H2O(1), [Ni (en)2]6 H3 [(VO)12 O6B18O42].8H2O(2), [Cu(en)2]5 H3 [(VO)12 O6B18 O42] [B(OH)3]2. 16H20(3) and(enH2)4 Na4H3 [(VO)12 O6B18O42].8H2O(4), were synthesized. The relationship between their properties and structures were studied by using FTIR, UV-Vis DRS and fluorescence etc. Among these compounds, compound (1) possesses isolated [(VO)12O6B18O42] cage, there is a ring of B18O42 sandwiched between two vanadium-oxygen clusters V6O18 by eighteen B--(micro3--O)--V bonds, while compound (2) is rather six [Ni(en)2], each connected with the B18O42 ring by two Ni--(micro3--O)--B. In compounds (3) and (4), the anion clusters [(VO)12 O6B18O42]13- are connected with [Cu(en)2]2+ and Na+ , respectively. Thus, the compounds (3) and (4) are extended to an infinite two-dimensional network structure, respectively. These characteristic vibrational frequencies of polyoxovanadium borates are related to the structures of these compounds. In UV/Vis DRS spectra, there are two characteristic peaks of polyoxometalates at 205 and 260 nm, respectively. The fluorescence spectra of these four compounds have been studied, and they have emission peaks at 415 nm excited by 310 nm which are caused by Omicro-->Mo. The fluorescence lifetimes of these compounds have been studied.