Recent data suggest that vascular endothelial growth factor receptor inhibitor (VEGFRi) can enhance the anti-tumor activity of the anti-programmed cell death-1 (anti-PD-1) antibody in colorectal cancer (CRC) with microsatellite stability (MSS). However, the comparison between this combination and standard third-line VEGFRi treatment is not performed, and reliable biomarkers are still lacking. We retrospectively enrolled MSS CRC patients receiving anti-PD-1 antibody plus VEGFRi (combination group, n=54) or VEGFRi alone (VEGFRi group, n=32), and their efficacy and safety were evaluated. We additionally examined the immune characteristics of the MSS CRC tumor microenvironment (TME) through single-cell and spatial transcriptomic data, and an MSS CRC immune cell-related signature (MCICRS) that can be used to predict the clinical outcomes of MSS CRC patients receiving immunotherapy was developed and validated in our in-house cohort. Compared with VEGFRi alone, the combination of anti-PD-1 antibody and VEGFRi exhibited a prolonged survival benefit (median progression-free survival: 4.4 vs. 2.0 months, P=0.0024; median overall survival: 10.2 vs. 5.2 months, P=0.0038) and a similar adverse event incidence. Through single-cell and spatial transcriptomic analysis, we determined ten MSS CRC-enriched immune cell types and their spatial distribution, including naive CD4⁺ T, regulatory CD4⁺ T, CD4⁺ Th17, exhausted CD8⁺ T, cytotoxic CD8⁺ T, proliferated CD8⁺ T, natural killer (NK) cells, plasma, and classical and intermediate monocytes. Based on a systemic meta-analysis and ten machine learning algorithms, we obtained MCICRS, an independent risk factor for the prognosis of MSS CRC patients. Further analyses demonstrated that the low-MCICRS group presented a higher immune cell infiltration and immune-related pathway activation, and hence a significant relation with the superior efficacy of pan-cancer immunotherapy. More importantly, the predictive value of MCICRS in MSS CRC patients receiving immunotherapy was also validated with an in-house cohort. Anti-PD-1 antibody combined with VEGFRi presented an improved clinical benefit in MSS CRC with manageable toxicity. MCICRS could serve as a robust and promising tool to predict clinical outcomes for individual MSS CRC patients receiving immunotherapy.
Humans ; Colorectal Neoplasms/drug therapy* ; Male ; Female ; Immunotherapy ; Middle Aged ; Aged ; Tumor Microenvironment/immunology* ; Retrospective Studies ; Microsatellite Instability ; Transcriptome ; Single-Cell Analysis ; Programmed Cell Death 1 Receptor/immunology* ; Gene Expression Profiling ; Immune Checkpoint Inhibitors/therapeutic use* ; Adult ; Receptors, Vascular Endothelial Growth Factor/antagonists & inhibitors*

OBJECTIVE: Cigarette smoking exacerbates the progression of pulmonary tuberculosis (TB). The role of tertiary lymphoid structures (TLS) in chronic lung diseases has gained attention; however, it remains unclear whether smoking-exacerbated lung damage in TB is associated with TLS. This study aimed to analyze the characteristics of pulmonary TLS in smokers with TB and to explore the possible role of TLS in smoking-related lung injury in TB. METHODS: Lung tissues from 36 male patients (18 smokers and 18 non-smokers) who underwent surgical resection for pulmonary TB were included in this study. Pathological and immunohistological analyses were conducted to evaluate the quantity of TLS, and chest computed tomography (CT) was used to assess the severity of lung lesions. The correlation between the TLS quantity and TB lesion severity scores was analyzed. The immune cells and chemokines involved in TLS formation were also evaluated and compared between smokers and non-smokers. RESULTS: Smoker patients with TB had significantly higher TLS than non-smokers ( P < 0.001). The TLS quantity in both the lung parenchyma and peribronchial regions correlated with TB lesion severity on chest CT (parenchyma: r = 0.5767; peribronchial: r = 0.7373; both P < 0.001). Immunohistochemical analysis showed increased B cells, T cells, and C-X-C motif chemokine ligand 13 (CXCL13) expression in smoker patients with TB ( P < 0.001). CONCLUSION Smoker TB patients exhibited increased pulmonary TLS, which was associated with exacerbated lung lesions on chest CT, suggesting that cigarette smoking may exacerbate lung damage by promoting TLS formation.
Humans ; Male ; Tuberculosis, Pulmonary/immunology* ; Middle Aged ; Tertiary Lymphoid Structures/pathology* ; Adult ; Lung/pathology* ; Smoking/adverse effects* ; Smokers ; Aged ; Tomography, X-Ray Computed

L-valine is an important branched-chain amino acid widely used in the food, pharmaceutical, and feed industries. Microbial fermentation has become the primary production method for L-valine. However, current industrial production still faces issues such as inefficient carbon flux utilization, imbalance in cofactor supply and demand, and suboptimal fermentation processes, which limit the efficient synthesis of L-valine. To further enhance the production performance of L-valine, In this study, metabolic engineering was conducted for a previously constructed Escherichia coli strain with a high yield of L-valine to optimize carbon flux distribution and balance cofactor consumption. Dual-phase oxygen-controlled fermentation was carried out to enhance L-valine production. Firstly, to address the pyruvate loss, we knocked out multiple competing pathway genes (ldhA, poxB, pflB, frdA, and pta), which resulted in a 48% increase in flask yield of the constructed strain VL-04. Next, we optimized the cofactor supply and demand balance by replacing ilvE with bcd (NADH-preferential) from Bacillus subtilis to construct the strain VL-06, which achieved a flask yield of 22.80 g/L, a further improvement of 25.8%. Subsequently, the fermentation conditions of VL-06 were optimized in a 5 L bioreactor with dual-phase oxygen-controlled fermentation. After optimization, the L-valine production reached 86.44 g/L in 26 h, with a glucose-to-acid conversion rate of 44.08% and a production intensity of 3.32 g/(L·h). This study not only shortens the time for L-valine production but also improves the economic efficiency, providing insights for similar fermentation processes employing dual-phase oxygen control.
Metabolic Engineering/methods* ; Escherichia coli/genetics* ; Valine/biosynthesis* ; Fermentation ; Bacillus subtilis/genetics*

Objective To design an anti-inversion performance evaluation system for ankle braces and validate its performance.Methods The system was composed of a simulation system,an inversion angle acquisition system,a lateral tension acquisition system for ankle joint and a data collection and procession system.The simulation platform made of aluminum alloy consisted of a standing platform and a landing pad,and the landing pad was made up of a platform and a slope for landing;the inversion angle acquisition system included markers,an image acquisition device and a fill light.The lateral tension acquisition system involved in a tension sensor,a detection sensor and an elastic cloth for fixation.The data collection and procession system comprised of a computer or smartphone,iXControl software,iXViewer software and a cell phone App that received real-time data from the lateral ankle tension acquisition device.The system developed underwent performance validation when applied to evaluating anti-inversion performance of volunteers without or with flexible or new braces.The traditional EMG testing method was used for EMG data acquisition for volunteers without or with flexible or new braces,and the consistency was explored between the testing results by the traditional method and the system.Results The system developed could evaluate the anti-inversion performance of ankle braces by simulating the process of ankle inversion during human high-altitude landing,and the results had high consistency with those by traditional EMG testing methods.Conclusion The system developed with simple structure and easy operation evaluates the anti-inversion performance of ankle braces.[Chinese Medical Equipment Journal,2024,45(11):21-26]

Objective To investigate the risk factors for bronchopulmonary dysplasia(BPD)in twin preterm infants with a gestational age of<34 weeks,and to provide a basis for early identification of BPD in twin preterm infants in clinical practice.Methods A retrospective analysis was performed for the twin preterm infants with a gestational age of<34 weeks who were admitted to 22 hospitals nationwide from January 2018 to December 2020.According to their conditions,they were divided into group A(both twins had BPD),group B(only one twin had BPD),and group C(neither twin had BPD).The risk factors for BPD in twin preterm infants were analyzed.Further analysis was conducted on group B to investigate the postnatal risk factors for BPD within twins.Results A total of 904 pairs of twins with a gestational age of<34 weeks were included in this study.The multivariate logistic regression analysis showed that compared with group C,birth weight discordance of>25%between the twins was an independent risk factor for BPD in one of the twins(OR=3.370,95%CI:1.500-7.568,P<0.05),and high gestational age at birth was a protective factor against BPD(P<0.05).The conditional logistic regression analysis of group B showed that small-for-gestational-age(SGA)birth was an independent risk factor for BPD in individual twins(OR=5.017,95%CI:1.040-24.190,P<0.05).Conclusions The development of BPD in twin preterm infants is associated with gestational age,birth weight discordance between the twins,and SGA birth.

Objective To investigate the effect of percutaneous endoscopic transforaminal discectomy(PETD)on L5-S1 lumbar disc herniation(LDH)and the influence of iliac crest height on the clinical efficacy.Methods A total of 86 patients treated with PETD for LDH(L5-S1 segment)from February 2019 to February 2018 were selected and grouped according to the relationship between the highest point of the iliac crest and the position of the L4-5 pedicle.Forty-eighty patients with the highest point of the iliac crest located below the upper edge of the L5 pedicle were included in group A;thirty-three patients with the highest point of the iliac crest located between the lower edge of the L4 pedicle and the upper edge of the L5 pedicle were included in group B,and five patients with the highest point of the iliac crest located above the lower edge of the L4 pedicle were included in group C.The operation indexes of the three groups were compared.The visual analogue score(VAS)and Oswestry Disability index(ODI)before and after surgery[preoperative(T0),1 week after surgery(T1),1 month,6 months and 12 months after surgery(T2,T3,T4)]were compared among the three groups.Results There was no difference in operation time and blood loss among the three groups(P>0.05).At T0,there was no difference in VAS score and ODI among the three groups(P>0.05).At T1-T4,when VAS score and ODI of the three groups were lower than that at T0,VAS in group A and B was lower than that in group C(P<0.05),but there was no difference between group A and B(P>0.05).Conclusion PETD has significantly clinical efficacy in the treatment of L5-S1 LDH,and whether the iliac crest height is higher than the level of the lower edge of the L4 pedicle will affect its clinical efficacy.

Objective To express recombinant Burkholderia pseudomallei(B.pseudomallei)type Ⅲ secretion system BipD protein,prepare its polyclonal antibodies and verify their immunological traits.Methods The recombinant pET-28a-BipD plasmid was generated,and the pET-28a-BipD-carried E.coli BL21(DE3)bacteria were induced with isopropyl-β-d-thiogalactoside(IPTG)to express recombinant BipD(rBipD)protein.The rBipD was obtained by affinity chromatography using His Trap column,then mixed with Fredrick's adjuvant to immunize BALB/c mice by intraperitoneal injection in order to obtain anti-rBipD polyclonal antibodies.The immunoreactivity of rBipD was detected by Western blot assay using rabbit anti-melioidosis serum and the serum from melioidosis patients.The immunogenicity of rBipD was evaluated using Western blotting and immunofluorescence staining.Finally,rBipD was used to establish an indirect ELISA to detect serum antibodies of clinical melioidosis patients.Results The recombinant plasmid pET-28a-BipD was successfully constructed and transformed into E.coli BL21(DE3)to induce rBipD expression with IPTG treatment.The obtained rBipD had a relative molecular weight of 36×103 and a purity of 95.4％,and had good immunogenicity and immunoreactivity.It could induce the production of specific antibodies after immunizing mice,and mouse polyclonal antibodies against rBipD were prepared with the titer of 1∶512 000.rBipD of 5.0 μg/mL produced specific immune response with the serum of melioidosis patients,but had no specific reaction with the serum of tuberculosis patients,with statistical difference(P＜0.01).Conclusion rBipD with immunological activity is successfully prepared and purified,and its polyclonal antibodies are also developed,which provide a good tool for clinical immunological diagnosis and study of immune mechanism of B.pseudomallei infection.

Objective To analyze the mechanism that Hcp1 protein in type Ⅵ secretion system of Burkholderia pseudomallei(B.pseudomallei)mediates the formation of multinucleated giant cells(MNGCs)when host cells are infected by the bacterium.Methods The mutant strain(BPC006 Δhcp1)and complementation strain(BPC006 Δhcp1::hcp1)were constructed by homologous recombination and plasmid complement technology,respectively.After RAW264.7 cells were infected with B.pseudomallei,the localization of Hcp1 in host cells was analyzed by immunofluorescence staining.The localization was further verified by cytoplasmic-membrane isolation in 293T cells after transfecting pCDNA4.1-Hcp1.The biological significance and effect of Hcp1 were explored by the anti-Hcp1 polyclonal antibody blocking and the formation of MNGC was detected by Giemsa staining.Results Western blotting showed that BPC006 Δhcp1 could not express Hcp1,while BPC006 Δhcp1::hcp1 restored Hcp1 expression.The above results proved that the mutant and complement strains were successfully constructed.Both cellular immunofluorescence co-localization and cytoplasmic-membrane isolation experiments showed that Hcp1 localized to host cell membranes.Last but not least,compared with the control group,anti-Hcp1 polyclonal antibodies inhibited the formation of MNGC(P＜0.01).Conclusion Hcp1 protein in type Ⅵ secretion system of B.pseudomallei is able to translocate to the RAW264.7 cell membranes and plays an important role in the formation of MNGCs.

Elemental imaging analysis based on laser induced-breakdown spectroscopy(LIBS)can provide significant reference value for oil and gas exploration activities.Improving the scanning speed and spatial resolution of LIBS elemental imaging analysis instruments contributes to enhancing the efficiency of mineral surface elemental analysis,which is crucial for achieving in-situ,real-time,and rapid LIBS analysis.In this study,a high-speed scanning LIBS elemental imaging analysis instrument was developed based on a scanning mirror device,achieving a scanning speed of 100 Hz and a spatial resolution of 50 μm.The stability of spectral data collected by this instrument was validated using aluminum alloy standard samples with uniform elemental distribution.The experimental results showed that the relative standard deviations(RSD)of the spectral data collected at different locations were 2.76％,2.79％,2.35％and 2.55％,respectively,demonstrating that the instrument's performance met analysis requirements.Analysis of spectral acquisition channels led to the selection of the 337-595 nm spectral range.Imaging analysis of major elements on the surface of meteorite mineral samples with complex matrices was conducted using this instrument,coupled with a multi-element imaging algorithm enabling visualization analysis of four major elements on the same image.The results revealed a higher level of detail and complexity in element distribution.The study demonstrated that this instrument,combined with multi-element imaging analysis algorithms,could provide crucial technical support for rapid imaging of element distribution in minerals at a microscopic scale during geological research.

Analgesia is an important link in the treatment of severe patients after neurosurgery and plays a vital role in improving the prognosis of the patients.Understanding the status quo and influencing fac-tors of pain in severe patients after neurosurgery helps to predict the occurrence of pain,which is crucial for determining the new pain assessment methods and auxiliary analgesic methods and developing novel analgesic drugs.This paper reviews the pain status,pain evaluation and analgesic methods of severe patients after neuro-surgery in recent years so as to understand the pain management current status of the patients with severe neurological conditions and provide reference for the medical staff to implement the analgesic programs.