Objective To analyze the effects of tyrosinase on choroidal and retinal thickness and blood flow changes in guinea pigs,and to explore the role of tyrosinase in the development and progression of myopia.Methods A total of 30 three-week-old male tri-colored guinea pigs and 10 albino guinea pigs were selected and divided into four groups:control group(tri-colored hyperopic guinea pigs,with no intervention),albino group(albino myopic guinea pigs,with no inter-vention),myopia group(tri-colored myopic guinea pigs,with no intervention),and injection group[tri-colored hyperopic guinea pigs,injected with tyrosinase inhibitor(6 250 μg·L-1),100 μL per day].The experiment lasted for 4 weeks.The refractive status and axial length(AL)of the guinea pigs in each group were measured,along with ocular biometric param-eters related to axial length[anterior chamber depth,aqueous humor depth(AQD),central corneal thickness,lens diame-ter,vitreous chamber depth(VCD)].Optical coherence tomography was used to measure the retinal thickness,choroidal thickness(ChT),and choroidal blood perfusion(ChBP)in different regions of the guinea pigs.The tyrosinase activity in the vitreous and retina of guinea pigs in each group was measured.The expression levels of neurotransmitters in the vitre-ous and retina of guinea pigs in each group were detected.Results The differences in refractive status between the albi-no group and the control group at 0,2,and 4 weeks of the experiment were statistically significant(F=8.972,P＜0.05).At the 4th week of the experiment,the refractive status of the injection group was lower than that of the control group,and the AL was greater than that of the control group,with statistically significant differences(both P＜0.05).Further analysis of AL-related biometric parameters revealed that only AQD and VCD were associated with the changes in AL of guinea pigs in each group.At the 0th week of the experiment,the average retinal thickness of the control group was greater than that of the albino group,with a statistically significant difference(t=-9.007,P＜0.000 1).Moreover,the differences in reti-nal thickness in the outer retina across different directions and time points were statistically significant(all P＜0.05).The differences in retinal thickness between the control and albino groups were mainly concentrated in the outer retina.The ChT of the albino group was less than that of the control group,with a significant difference between groups(F=4.809,P=0.030).The ChBP of the control group was significantly higher than that of the albino group at 0,2,and 4 weeks of the experiment(all P＜0.05).At the 4th week of the experiment,the tyrosinase activity in the vitreous of the injection,albi-no,and myopia groups was lower than that of the control group,with statistically significant differences(all P＜0.05).The differences in neurotransmitters between the albino and control groups were mainly concentrated in the vitreous.In the retina,the ornithine level in the myopia group was higher than that in the albino and control groups,and the tryptophan levels in the myopia and control groups were higher than that in the albino group,with statistically significant differences(all P＜0.05).Conclusion Tyrosinase plays a crucial role in the development of myopia,regulating the development of refractive status by influencing the physiological properties of the retina and choroid.

Owing to their high genetic and physiological similarities to humans,non-human primates(NHPs)have become pivotal animal models in life sciences research and biomedical development.NHP laboratory animals are not only an ideal platform for exploring the mechanisms of neurological diseases and infectious diseases,but they are also widely used in preclinical safety evaluations of macromolecular drugs,which are considered the"gold standard".Nevertheless,this biological similarity increases the risk of zoonotic disease transmission to personnel working with NHP laboratory animals,their tissues,and body fluids.In light of recent domestic and international outbreaks of zoonotic diseases as well as the implementation of the Biosafety Law,this study examines the occupational risk factors encountered by personnel working with NHPs.This includes biological,chemical,and physical factors.This paper also covers common zoonoses,classification of the corresponding pathogens,transmission routes,risk severity levels,and protocols for post-exposure management.A multidimensional prevention and control framework is proposed,which includes the following components.(1)Risk Assessment and Emergency Response:Regularly identify hazards through an Occupational Health and Safety Committee(OHSC)and develop post-exposure emergency protocols.(2)Optimization of Management Systems:Improve facility design,optimize the allocation of personal protective equipment,and enhance health surveillance and vaccination programs.(3)Technical Training and Standardized Operations:Provide specialized training in NHP laboratory animal ethology and biosafety practices.Additionally,implement intelligent monitoring technologies to reduce the occurrence of aggressive incidents.This paper outlines measures designed to enhance health and safety awareness among personnel working with NHP laboratory animals.It emphasizes the need for strengthened guidance on the use of personal protective equipment(PPE)and the standardization of professional operational practices.The goal is to safeguard personnel health and safety,reduce occupational exposure rates,and effectively prevent occupational diseases related to laboratory animals.

Owing to their high genetic and physiological similarities to humans,non-human primates(NHPs)have become pivotal animal models in life sciences research and biomedical development.NHP laboratory animals are not only an ideal platform for exploring the mechanisms of neurological diseases and infectious diseases,but they are also widely used in preclinical safety evaluations of macromolecular drugs,which are considered the"gold standard".Nevertheless,this biological similarity increases the risk of zoonotic disease transmission to personnel working with NHP laboratory animals,their tissues,and body fluids.In light of recent domestic and international outbreaks of zoonotic diseases as well as the implementation of the Biosafety Law,this study examines the occupational risk factors encountered by personnel working with NHPs.This includes biological,chemical,and physical factors.This paper also covers common zoonoses,classification of the corresponding pathogens,transmission routes,risk severity levels,and protocols for post-exposure management.A multidimensional prevention and control framework is proposed,which includes the following components.(1)Risk Assessment and Emergency Response:Regularly identify hazards through an Occupational Health and Safety Committee(OHSC)and develop post-exposure emergency protocols.(2)Optimization of Management Systems:Improve facility design,optimize the allocation of personal protective equipment,and enhance health surveillance and vaccination programs.(3)Technical Training and Standardized Operations:Provide specialized training in NHP laboratory animal ethology and biosafety practices.Additionally,implement intelligent monitoring technologies to reduce the occurrence of aggressive incidents.This paper outlines measures designed to enhance health and safety awareness among personnel working with NHP laboratory animals.It emphasizes the need for strengthened guidance on the use of personal protective equipment(PPE)and the standardization of professional operational practices.The goal is to safeguard personnel health and safety,reduce occupational exposure rates,and effectively prevent occupational diseases related to laboratory animals.

Objective To analyze the effects of tyrosinase on choroidal and retinal thickness and blood flow changes in guinea pigs,and to explore the role of tyrosinase in the development and progression of myopia.Methods A total of 30 three-week-old male tri-colored guinea pigs and 10 albino guinea pigs were selected and divided into four groups:control group(tri-colored hyperopic guinea pigs,with no intervention),albino group(albino myopic guinea pigs,with no inter-vention),myopia group(tri-colored myopic guinea pigs,with no intervention),and injection group[tri-colored hyperopic guinea pigs,injected with tyrosinase inhibitor(6 250 μg·L-1),100 μL per day].The experiment lasted for 4 weeks.The refractive status and axial length(AL)of the guinea pigs in each group were measured,along with ocular biometric param-eters related to axial length[anterior chamber depth,aqueous humor depth(AQD),central corneal thickness,lens diame-ter,vitreous chamber depth(VCD)].Optical coherence tomography was used to measure the retinal thickness,choroidal thickness(ChT),and choroidal blood perfusion(ChBP)in different regions of the guinea pigs.The tyrosinase activity in the vitreous and retina of guinea pigs in each group was measured.The expression levels of neurotransmitters in the vitre-ous and retina of guinea pigs in each group were detected.Results The differences in refractive status between the albi-no group and the control group at 0,2,and 4 weeks of the experiment were statistically significant(F=8.972,P＜0.05).At the 4th week of the experiment,the refractive status of the injection group was lower than that of the control group,and the AL was greater than that of the control group,with statistically significant differences(both P＜0.05).Further analysis of AL-related biometric parameters revealed that only AQD and VCD were associated with the changes in AL of guinea pigs in each group.At the 0th week of the experiment,the average retinal thickness of the control group was greater than that of the albino group,with a statistically significant difference(t=-9.007,P＜0.000 1).Moreover,the differences in reti-nal thickness in the outer retina across different directions and time points were statistically significant(all P＜0.05).The differences in retinal thickness between the control and albino groups were mainly concentrated in the outer retina.The ChT of the albino group was less than that of the control group,with a significant difference between groups(F=4.809,P=0.030).The ChBP of the control group was significantly higher than that of the albino group at 0,2,and 4 weeks of the experiment(all P＜0.05).At the 4th week of the experiment,the tyrosinase activity in the vitreous of the injection,albi-no,and myopia groups was lower than that of the control group,with statistically significant differences(all P＜0.05).The differences in neurotransmitters between the albino and control groups were mainly concentrated in the vitreous.In the retina,the ornithine level in the myopia group was higher than that in the albino and control groups,and the tryptophan levels in the myopia and control groups were higher than that in the albino group,with statistically significant differences(all P＜0.05).Conclusion Tyrosinase plays a crucial role in the development of myopia,regulating the development of refractive status by influencing the physiological properties of the retina and choroid.

Bacillus subtilis is recognized as a generally-regarded-as-safe strain, and has been widely used in the biosynthesis of high value-added products, including N-acetylneuraminic acid (NeuAc) which is widely used as a nutraceutical and a pharmaceutical intermediate. Biosensors responding to target products are widely used in dynamic regulation and high-throughput screening in metabolic engineering to improve the efficiency of biosynthesis. However, B. subtilis lacks biosensors that can efficiently respond to NeuAc. This study first tested and optimized the transport capacity of NeuAc transporters, and obtained a series of strains with different transport capacities for testing NeuAc-responsive biosensors. Subsequently, the binding site sequence of Bbr_NanR responding to NeuAc was inserted into different sites of the constitutive promoter of B. subtilis, and active hybrid promoters were obtained. Next, by introducing and optimizing the expression of Bbr_NanR in B. subtilis with NeuAc transport capacity, we obtained an NeuAc-responsive biosensor with wide dynamic range and higher activation fold. Among them, P535-N2 can sensitively respond to changes in intracellular NeuAc concentration, with the largest dynamic range (180-20 245) AU/OD. P566-N2 shows a 122-fold of activation, which is 2 times of the reported NeuAc-responsive biosensor in B. subtilis. The NeuAc-responsive biosensor developed in this study can be used to screen enzyme mutants and B. subtilis strains with high NeuAc production efficiency, providing an efficient and sensitive analysis and regulation tool for biosynthesis of NeuAc in B. subtilis.
N-Acetylneuraminic Acid/metabolism* ; Bacillus subtilis/metabolism* ; Promoter Regions, Genetic/genetics* ; Binding Sites ; Biosensing Techniques

Objective:To observe the effects of acupuncture at Houxi(SI3)and Huantiao(GB30)on the expression levels of nuclear factor kappa B(NF-κB),inducible nitric oxide synthase(iNOS),and nitric oxide(NO)of NF-κB inflammatory signaling pathway in L5 spinal nerve root of lumbar disc herniation(LDH)model rats and explore the mechanism of acupuncture in LDH treatment.Methods:Forty specific-pathogen-free healthy male Sprague-Dawley rats were randomly divided into a sham operation group,a model group,acupuncture group 1,and acupuncture group 2,with 10 rats in each group.The non-compression nucleus protrusion model was made by puncturing L4-L5 spinous process space and injecting autologous nucleus suspension.Acupuncture at bilateral Shenshu(BL23),Dachangshu(BL25),and Weizhong(BL40)was carried out in acupuncture group 1,and acupuncture at bilateral Houxi(SI3)and Huantiao(GB30)in acupuncture group 2.All rats were treated with balanced reinforcing and reducing needling manipulations,and the needles were retained for 30 min/time with one episode of needling manipulation every 10 min,once a day,14 times in total.The threshold value of paw withdrawal pain was measured by a thermal stimulation pain instrument;the serum NF-κB,iNOS,and NO levels were measured by enzyme-linked immunosorbent assay.The pathomorphological changes of spinal nerve roots were observed by hematoxylin-eosin(HE)staining;quantitative reverse transcription polymerase chain reaction was used to detect iNOS mRNA expression in spinal nerve roots;the NF-κB and iNOS protein expression in spinal nerve roots was detected by the immunofluorescence method.Results:Compared with the sham operation group,the threshold of paw withdrawal pain in the model group was decreased,and the expression levels of serum NF-κB,iNOS,and NO were increased;HE staining showed many degenerated and dissolved Schwann cells in spinal nerve roots with vacuolar changes;meanwhile,the expression levels of NF-κB and iNOS proteins,and the iNOS mRNA in spinal nerve roots were increased.Compared with the model group,the paw withdrawal pain thresholds in acupuncture group 1 and acupuncture group 2 were increased,and the increase in acupuncture group 2 was greater(P<0.05);the expression levels of serum NF-κB,iNOS,and NO in acupuncture group 1 and acupuncture group 2 were decreased,especially in acupuncture group 2(P<0.01);the vacuolar changes of spinal nerve roots,and the degeneration and lysis of Schwann cells in acupuncture group 1 and acupuncture group 2 were decreased,which were more obvious in acupuncture group 2;the NF-κB and iNOS protein expression and the iNOS mRNA expression levels in spinal nerve roots of acupuncture group 1 and acupuncture group 2 were decreased,especially in acupuncture group 2(P<0.01).Conclusion:Acupuncture at Houxi(SI3)and Huantiao(GB30)can improve the morphology of spinal nerve roots,inhibit the NF-κB and iNOS protein expression levels in spinal nerve roots and the serum NO level,and relieve the pain caused by inflammation of spinal nerve roots,which may be one of the mechanisms of acupuncture in LDH treatment.

Objective To investigate the clinicopathological characteristics of established genital and extragenital lichen sclerosus(LS)and compare the differences between them. Method The clinicopathological data of 55 patients with established genital and extragenital LS diagnosed by pathological examination in the Department of Dermatology of Beijing Hospital were retrospectively analyzed. Results The 55 patients included 11 males and 44 females.Among them,38,15,and 2 patients had genital lesions,extragenital lesions,and both genital and extragenital lesions,respectively.Extragenital LS mainly involved the back(14.55%)and extremities(7.27%).Among the patients,28.30% were asymptomatic,and 73.58% and 24.53% felt itchy and painful,respectively.The asymptomatic patients had a higher proportion in extragenital cases(
Darier Disease ; Extremities ; Female ; Genitalia ; Humans ; Lichen Sclerosus et Atrophicus/epidemiology* ; Male ; Retrospective Studies

Objective·To identify the relationship between the estimated fetal weight (EFW) discordance and birth weight (BW) discordance, and evaluate the accuracy of ultrasonography in predicting birth weight discordance (△BW) of twin pregnancy. Methods·The ultrasound was used to detect the growth of twins at different gestational weeks and the data were analyzed to compare the difference between EFW discordance (△EFW) and ?BW. Results·About 15.9 percent of twins (totally 277 cases) had severe △BW (△BW ≥20%) in our study, and the percentages of dichorionic-diamniotic twin (DCDA) and monochorionic-diamniotic twin (MCDA) were 68.2% and 31.8%, respectively (P>0.01). Compared with △EFW in other gestational weeks,△EFW last time before parturition was most consistent of △BW. Furthermore, the negative predictive value of MCDA was highest (94%) at 22-24 gestational weeks. Conclusion·Twin △BW was relatively better predicted by △EFW last time before parturition. Twin pregnancy without severe △EFW (△EFW<20%), especially MCDA with △EFW<20% at 22-24 weeks, had low probability of selective intrauterine growth restriction in the future.