BACKGROUND:Upper lumbar spinal stenosis is a multifactorial degenerative disorder of the spine.For narrowing of the spinal canal in the upper lumbar region(L1-L4),surgical decision-making is particularly complex.Existing minimally invasive surgeries each have their own advantages and limitations.Currently,there are few reports on biomechanical comparison and finite element analysis of different surgical methods for the treatment of high lumbar spinal stenosis.OBJECTIVE:To analyze the biomechanical impact of endoscopic unilateral laminotomy for bilateral decompression,transforaminal endoscopic lumbar decompression,and cross-overtop decompression in the treatment of upper lumbar spinal stenosis using endoscopy,and to verify the reliability and effectiveness of these three surgical techniques in treating upper lumbar spinal stenosis,providing a biomechanical basis for clinical decision-making.METHODS:The CT images of the lumbar spine of a healthy volunteer were selected,and the finite element model M0 of the normal lumbar L1-L5 segments was established using Mimics,Geomagic,Solid works,and Ansys software.The L2-L3 segment,representing upper lumbar characteristics,was chosen.Based on this model,the surgical models for endoscopic unilateral laminotomy for bilateral decompression(M1),transforaminal endoscopic lumbar decompression(M2),and cross-overtop decompression(M3)were established.Using software,the changes in the range of motion of the entire lumbar segment and the maximum Von Mises stress of the intervertebral discs were simulated and evaluated for each group of models under six loading conditions:flexion,extension,left lateral bending,right lateral bending,left rotation,and right rotation.RESULTS AND CONCLUSION:(1)Compared with model MO,the range of motion in M1,M2,and M3 increased under all six conditions,with M1 showing a greater increase.(2)M1 and M2 demonstrated significant increases in range of motion under forward bending,extension,and right rotation,while the increase under other conditions remained below 7％.(3)Compared with model M3,model M1 exhibited slightly increased overall joint range of motion during extension and left bending,while no significant changes were observed in other aspects,and the L1-L5 lumbar segments did not reach an unstable state.(4)In model M1,the maximum Von Mises stress of the intervertebral discs increased most significantly under flexion and extension loading conditions.However,under left lateral bending,right lateral bending,left rotation,and right rotation loading conditions,the increase did not exceed 5％.(5)These findings suggest that due to the sagittal anatomical characteristics of the facet joints,the unilateral laminotomy for bilateral decompression technique,while decompressing,involves resection of more facet joints,which impacts overall segmental stability.The transforaminal endoscopic lumbar decompression technique is suitable for patients with foraminal stenosis but cannot achieve complete decompression for those with severe ventral central stenosis.The Cross-Overtop technique effectively enlarges the volume of the central canal and lateral recess,optimizing decompression,and shows unique advantages in treating upper lumbar spinal stenosis.

BACKGROUND:Upper lumbar spinal stenosis is a multifactorial degenerative disorder of the spine.For narrowing of the spinal canal in the upper lumbar region(L1-L4),surgical decision-making is particularly complex.Existing minimally invasive surgeries each have their own advantages and limitations.Currently,there are few reports on biomechanical comparison and finite element analysis of different surgical methods for the treatment of high lumbar spinal stenosis.OBJECTIVE:To analyze the biomechanical impact of endoscopic unilateral laminotomy for bilateral decompression,transforaminal endoscopic lumbar decompression,and cross-overtop decompression in the treatment of upper lumbar spinal stenosis using endoscopy,and to verify the reliability and effectiveness of these three surgical techniques in treating upper lumbar spinal stenosis,providing a biomechanical basis for clinical decision-making.METHODS:The CT images of the lumbar spine of a healthy volunteer were selected,and the finite element model M0 of the normal lumbar L1-L5 segments was established using Mimics,Geomagic,Solid works,and Ansys software.The L2-L3 segment,representing upper lumbar characteristics,was chosen.Based on this model,the surgical models for endoscopic unilateral laminotomy for bilateral decompression(M1),transforaminal endoscopic lumbar decompression(M2),and cross-overtop decompression(M3)were established.Using software,the changes in the range of motion of the entire lumbar segment and the maximum Von Mises stress of the intervertebral discs were simulated and evaluated for each group of models under six loading conditions:flexion,extension,left lateral bending,right lateral bending,left rotation,and right rotation.RESULTS AND CONCLUSION:(1)Compared with model MO,the range of motion in M1,M2,and M3 increased under all six conditions,with M1 showing a greater increase.(2)M1 and M2 demonstrated significant increases in range of motion under forward bending,extension,and right rotation,while the increase under other conditions remained below 7％.(3)Compared with model M3,model M1 exhibited slightly increased overall joint range of motion during extension and left bending,while no significant changes were observed in other aspects,and the L1-L5 lumbar segments did not reach an unstable state.(4)In model M1,the maximum Von Mises stress of the intervertebral discs increased most significantly under flexion and extension loading conditions.However,under left lateral bending,right lateral bending,left rotation,and right rotation loading conditions,the increase did not exceed 5％.(5)These findings suggest that due to the sagittal anatomical characteristics of the facet joints,the unilateral laminotomy for bilateral decompression technique,while decompressing,involves resection of more facet joints,which impacts overall segmental stability.The transforaminal endoscopic lumbar decompression technique is suitable for patients with foraminal stenosis but cannot achieve complete decompression for those with severe ventral central stenosis.The Cross-Overtop technique effectively enlarges the volume of the central canal and lateral recess,optimizing decompression,and shows unique advantages in treating upper lumbar spinal stenosis.

Objective To establish a method for simultaneous determination of four high-molecular-weight thiol derivatives (TDs) in workplace air by gas chromatography. Methods The four kinds of vapor-phase macromolecular TDs (1-pentanethiol, 1-hexanethiol, 1-benzyl mercaptan, and n-octanethiol) in the workplace air were collected using the GDH-1 air sampling tubes, desorbed with anhydrous ethanol, separated on a DB-FFAP capillary column, and determined by flame ionization detector. Results The quantitation range of the four TDs was 0.30-207.37 mg/L, with the correlation coefficients greater than 0.999 00. The minimum detection mass concentrations and minimum quantitation mass concentrations were 0.18-0.32 and 0.60-1.05 mg/m³, respectively (both calculated based on the 1.5 L sample and 3.0 mL desorption solvent). The mean desorption efficiencies ranged from 87.07% to 103.59%. The within-run and between-run relative standard deviations were 1.92%-8.22% and 1.89%-8.45%, respectively. The samples can be stored at room temperature or 4 ℃ for three days and up to 7 days at -18 ℃. Conclusion This method is suitable for the simultaneous determination of four vapor-phase TDs in workplace air.

Objective To investigate the role of cytochrome P450 2E1 (CYP2E1) in trichloroethylene (TCE)-induced skin sensitization and liver damage in guinea pigs, using diallyl sulfide (DAS), a CYP2E1 inhibitor, as an intervention. Methods Specific pathogen-free female guinea pigs were randomly divided into blank control group, solvent control group, positive control (2,4-dinitrochlorobenzene) group, TCE-exposure group, and DAS-intervention group. Skin sensitization experiments were conducted using the guinea pig TCE maximal dose-skin sensitization test. Urinary trichloroacetic acid levels were determined following TCE induction and challenge. At 48 hours after the final challenge, serum liver function markers and inflammatory cytokines levels were detected. Histopathological examination on skin and liver tissues was performed, and hepatic CYP2E1 protein expression and oxidative stress indicators were assessed. Results The sensitization rates of guinea pigs were 100.0%, 75.0%, and 33.3% in the positive control, TCE-exposure, and DAS-intervention groups, respectively, while the blank control and solvent control groups were both 0.0%. Compared with the guinea pigs in TCE-exposure group, those in the DAS-intervention group had lower urinary trichloroacetic acid levels at intradermal induction, local induction, first challenge, and 24 hours after the final challenge time point (all P<0.05). Histopathology of guinea pigs showed dermal inflammatory infiltration and basal keratinocyte necrosis in the TCE-exposure group, whereas only mild dermal inflammation was observed in the DAS-intervention group. The guinea pigs in TCE-exposure group exhibited diffuse hepatocellular necrosis, while hepatic damage in the DAS-intervention group was alleviated, characterized by only mild hepatocellular steatosis and hepatocyte swelling around the central vein. The skin sensitization rate of guinea pigs in the TCE-exposure group increased (all P<0.01), the serum alanine aminotransferase (ALT )activity, the levels of interleukin (IL)-2, IL-17, and tumor necrosis factor-α (TNF- α) increased (all P<0.05), the relative expression of CYP2E1 protein, the activity of superoxide dismutase (SOD), and the level of malondialdehyde in liver tissue increased (all P<0.05), while the activity of catalase decreased (P<0.05), compared with the blank control and solvent control groups. The serum ALT activity and the levels of IL-2, IL-17, and TNF-α of guinea pigs in DAS-intervention group reduced (all P<0.05), as well as CYP2E1 protein expression, SOD activity, and malondialdehyde level in liver tissue reduced (all P<0.05), compared with the TCE-exposure group. Conclusion TCE can induce hepatic CYP2E1 expression, thereby promoting oxidative stress and inflammatory responses, which contributes to skin sensitization and liver damage. DAS alleviates TCE-induced toxic effects on skin and liver by inhibiting CYP2E1 expression.

Objective:To understand the current status of the actual protective effect of respiratory protective equipment (RPE) for workers exposed to trichloroethylene (TCE), and to explore the factors affecting the actual protective effect.Methods:From July to December 2023, a total of 75 workers occupationally exposed to TCE from 21 hardware and electronics manufacturing facilities in a province were selected as research objects by convenient sampling method. Workplace protection factor (WPF) was used as an index to evaluate the actual protective effect of workers' RPE. The concentration of TCE inside and outside the RPE was detected to calculate WPE, and the temperature, humidity and wind speed near the working place were measured, as well as the forced vital capacity, respiratory rate, heart rate and other indicators of the worker were measured. The log-transformed WPF value (lgWPF) followed a normal distribution. One-sample t-test was used to compare the difference between the mean lgWPF and the log value of the assigned protection factor (APF) of the half mask (lgAPF=1). Multiple linear regression model was used to investigate the influencing factors of lgWPF. Results:The lgWPF of 75 TCE-exposed workers ranged from 0.40 to 1.32 (0.84±0.22). The mean of lgWPF was lower than that of lgAPF, and the difference was statistically significant ( t=-6.37, P<0.001). After adjusting for confounding factors, the results of multiple linear regression showed that humidity, forced vital capacity and respiratory rate were negatively correlated with lgWPF ( β=-0.008, -0.079, -0.021, P<0.05) . Conclusion:The actual protective efficacy of RPE among workers exposed to TCE is suboptimal. High humidity, elevated forced vital capacity, and increased respiratory rate may be contributing factors to the diminished protective performance of RPE.

Objective:To understand the current status of the actual protective effect of respiratory protective equipment (RPE) for workers exposed to trichloroethylene (TCE), and to explore the factors affecting the actual protective effect.Methods:From July to December 2023, a total of 75 workers occupationally exposed to TCE from 21 hardware and electronics manufacturing facilities in a province were selected as research objects by convenient sampling method. Workplace protection factor (WPF) was used as an index to evaluate the actual protective effect of workers' RPE. The concentration of TCE inside and outside the RPE was detected to calculate WPE, and the temperature, humidity and wind speed near the working place were measured, as well as the forced vital capacity, respiratory rate, heart rate and other indicators of the worker were measured. The log-transformed WPF value (lgWPF) followed a normal distribution. One-sample t-test was used to compare the difference between the mean lgWPF and the log value of the assigned protection factor (APF) of the half mask (lgAPF=1). Multiple linear regression model was used to investigate the influencing factors of lgWPF. Results:The lgWPF of 75 TCE-exposed workers ranged from 0.40 to 1.32 (0.84±0.22). The mean of lgWPF was lower than that of lgAPF, and the difference was statistically significant ( t=-6.37, P<0.001). After adjusting for confounding factors, the results of multiple linear regression showed that humidity, forced vital capacity and respiratory rate were negatively correlated with lgWPF ( β=-0.008, -0.079, -0.021, P<0.05) . Conclusion:The actual protective efficacy of RPE among workers exposed to TCE is suboptimal. High humidity, elevated forced vital capacity, and increased respiratory rate may be contributing factors to the diminished protective performance of RPE.

Biotoxins, which include bacterial, fungal, marine, plant, and animal toxins, are widespread in living and occupational environments, posing potential threats to human health. Rapid detection of biotoxins in blood is crucial for preventing health hazards and enabling timely disease diagnosis and treatment. Biosensors and immunoassay technologies have critical advantages in the rapid detection of biotoxins in blood. Common biosensors, such as surface plasmon resonance biosensors and fluorescent biosensors, enhance sensitivity and reduce detection limits through signal amplification. Common immunoassay methods, such as colloidal gold immunochromatography, fluorescence immunochromatography, and chemiluminescence immunoassay, improve detection efficacy and sensitivity through specific antibody-antigen binding and nanotechnology. However, current rapid detection technologies of bitoxins in blood face challenges such as matrix interference and insufficient specificity, and they fall short in high-throughput detection of multiple toxins simultaneously. Future developments should focus on improving sample pretreatment, innovating signal amplification methods, enhancing specificity on recognition of elements, and designing portable detection devices and high-throughput platforms for simultaneous toxin analysis. These advancements aim to improve the sensitivity and reliability of detection methods, providing more accurate and convenient solutions for biotoxin detection in blood.

BACKGROUND:Semaphone 3A(Sema3A)is an important neurovascular growth inhibitor.It is not clear how Sema3A is involved in the pathogenesis of discogenic low back pain.Exploring the potential mechanism of Sema3A in intervertebral disc degeneration can provide a new target and theoretical basis for the prevention and treatment of discogenic low back pain. OBJECTIVE:To explore the mechanism of interleukin-1β inhibiting the expression of Sema3A by activating the nuclear factor-κB signaling pathway to induce intervertebral disc degeneration in rats. METHODS:RT-qPCR was used to detect the expression of Sema3A mRNA in normal and degenerative human nucleus pulposus tissues.Nucleus pulposus cells of Sprague-Dawley rats were isolated,cultured,and passaged to the 3rd generation.Then,passage 3 cells were divided into three groups:the blank control group was routinely cultured for 48 hours,the degeneration group was intervened with 10 ng/mL interleukin 1β for 48 hours,and the degeneration+inhibitor group was treated by 5 μmol/L nuclear factor-κB signaling pathway-specific inhibitor BAY11-7082 for 1 hour,followed by interleukin-1β for 48 hours.At the end of the intervention,cell viability was detected by cell counting kit-8,cell apoptosis was detected by Annexin V/FITC staining,mRNA expression of cellular matrix,vascular and neural markers and Sema3A was detected by RT-qPCR,and protein expression of marker proteins,p65 and p-p65 was detected by western blot. RESULTS AND CONCLUSION:RT-qPCR assay showed that the expression of Sema3A mRNA was lower in degenerative human nucleus pulposus tissue than in normal human nucleus pulposus tissue(P＜0.05).Compared with the blank control group,the nucleus pulposus cell viability decreased and the apoptotic rate increased in the degeneration group(P＜0.05);compared with the degeneration group,the nucleus pulposus cell viability increased and the apoptotic rate decreased in the degeneration + inhibitor group(P＜0.05).Compared with the blank control group,mRNA expression of type Ⅱ collagen,polyproteoglycan,and Sema3A was decreased in the degeneration group(P＜0.05),while mRNA expression of CD31 and neurofilament 200 was increased(P＜0.05).Compared with the degeneration group,mRNA expression of type Ⅱ collagen,polyproteoglycan,and Sema3A was elevated in the degeneration+inhibitor group(P＜0.05)and mRNA expression of CD31 and neurofilament 200 decreased(P＜0.05).Compared with the blank control group,the protein expression of type Ⅱ collagen,polyproteoglycan,and Sema3A was decreased in the degeneration group(P＜0.05),and the protein expression of CD31,neurofilament protein 200,p65,and p-p65 was elevated(P＜0.05);compared with the degeneration group,the protein expression of type Ⅱ collagen,polyproteoglycan,and Sema3A was elevated in the degeneration+inhibitor group(P＜0.05),and protein expression of CD31,neurofilament 200,p65,and p-p65 was decreased(P＜0.05).To conclude,interleukin-1β does inhibit the expression of Sema3A by activating the nuclear factor-κB signaling pathway,which can also increase the degradation of extracellular matrix,promote the innervation and angiogenesis in degenerative intervertebral disc,and may be one of potential factors that contribute to intervertebral disc degeneration and discogenic low back pain.

AIM: To compare the short-term postoperative visual acuity, visual disturbance phenomena, and spectacle independence rate in patients who underwent monocular implantation with trifocal, multifocal, or extended range of vision intraocular lens(IOL).METHODS: A retrospective analysis was conducted on 67 cataract patients(67 eyes)who underwent phacoemulsification cataract extraction combined with IOL implantation from March 2019 to December 2022. A total of 35 cases(35 eyes)received Symfony extended range of vision IOL implantation, 21 cases(21 eyes)received AcrySof IQ ReSTOR +3D multifocal IOL, and 11 cases(11 eyes)received AcrySof IQ PanOptix trifocal IOL. The preoperative uncorrected distance visual acuity(UDVA), uncorrected intermediate visual acuity(UIVA), and uncorrected near visual acuity(UNVA)and 3 mo postoperatively were documented. Moreover, defocus curves, visual disturbance phenomena, and spectacle independence rates were recorded at 3 mo postoperatively.RESULTS: At 3 mo postoperatively, no statistically significant differences were observed in UDVA among the three groups(P>0.05). A comparison of UIVA showed superior results in the Symfony and PanOptix groups compared to the ReSTOR group(all P<0.01). The UNVA of both the ReSTOR and PanOptix groups outperformed the Symfony group(all P<0.01). The defocus curves indicated that in the intermediate vision range(-1.00 to -1.50 D), the Symfony group exhibited better performance than the ReSTOR group(P<0.05); while in the near vision range(-2.50 to -3.50 D), the ReSTOR group was superior to the Symfony group(P<0.05). The PanOptix group demonstrated superior visual acuity in the near vision range(-2.00 to -3.50 D)compared to the Symfony group(P<0.05)and was also superior in the intermediate vision range(-1.00 to -2.00 D)compared to the ReSTOR group(P<0.05). No significant differences were observed in the incidence of glare or halo and binocular interference phenomena among the three groups(P>0.05). The PanOptix and ReSTOR groups exhibited a higher spectacle independence rate compared to the Symfony group(P<0.0167).CONCLUSION: Compared to Symfony extended range of vision IOL and ReSTOR multifocal IOL, PanOptix trifocal IOL offers a balanced approach to distance, intermediate, and near visual acuity, without a high incidence of glare and halo, and with a higher spectacle independence rate. Caution is still advised when considering monocular implantation with presbyopia-correcting IOLs.

Objective:To explore the feasibility of deep learning-based restoration of obscured thyroid ultrasound images.Methods:A total of 358 images of thyroid nodules were retropectively collected from January 2020 to October 2021 at Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, and the images were randomly masked and restored using DeepFillv2. The difference in grey values between the images before and after restoration was compared, and 6 sonographers (2 chief physicians, 2 attending physicians, 2 residents) were invited to compare the rate of correctness of judgement and detection of image discrepancies. The ultrasound features of thyroid nodules (solid composition, microcalcifications, markedly hypoechoic, ill-defined or irregular margins, or extrathyroidal extensions, vertical orientation and comet-tail artifact) were extracted according to the Chinese Thyroid Imaging Reporting and Data System (C-TIRADS). The consistency of ultrasound features of thyroid nodules before and after restoration were compared.Results:The mean squared error of the images before and after restoration ranged from 0.274 to 0.522, and there were significant differences in the rate of correctness of judgement and detection of image discrepancies between physicians of different groups(all P<0.001). The overall accuracy rate was 51.95%, the overall detection rate was 1.79%, there were significant differences also within the chief physicians and resident groups (all P<0.001). The agreement rate of all ultrasound features of the nodules before and after image restoration was higher than 70%, over 90% agreement rate for features such as solid composition and comet-tail artifact. Conclusions:The algorithm can effectively repair obscured thyroid ultrasound images while preserving image features, which is expected to expand the deep learning image database, and promote the development of deep learning in the field of ultrasound images.