Measurements of All-Particle Energy Spectrum and Mean Logarithmic Mass of Cosmic Rays from 0.3 to 30 PeV with LHAASO-KM2A

We present the measurements of all-particle energy spectrum and mean logarithmic mass of cosmic rays in the energy range of 0.3-30 PeV using data collected from LHAASO-KM2A between September 2021 and December 2022, which is based on a nearly composition-independent energy reconstruction method, achieving unprecedented accuracy. Our analysis reveals the position of the knee at 3.67±0.05±0.15  PeV. Below the knee, the spectral index is found to be -2.7413±0.0004±0.0050, while above the knee, it is -3.128±0.005±0.027, with the sharpness of the transition measured with a statistical error of 2%. The mean logarithmic mass of cosmic rays is almost heavier than helium in the whole measured energy range. It decreases from 1.7 at 0.3 PeV to 1.3 at 3 PeV, representing a 24% decline following a power law with an index of -0.1200±0.0003±0.0341. This is equivalent to an increase in abundance of light components. Above the knee, the mean logarithmic mass exhibits a power law trend towards heavier components, which is reversal to the behavior observed in the all-particle energy spectrum. Additionally, the knee position and the change in power-law index are approximately the same. These findings suggest that the knee observed in the all-particle spectrum corresponds to the knee of the light component, rather than the medium-heavy components.

Measurement of Ultra-High-Energy Diffuse Gamma-Ray Emission of the Galactic Plane from 10 TeV to 1 PeV with LHAASO-KM2A

The diffuse Galactic γ-ray emission, mainly produced via interactions between cosmic rays and the interstellar medium and/or radiation field, is a very important probe of the distribution, propagation, and interaction of cosmic rays in the Milky Way. In this Letter, we report the measurements of diffuse γ rays from the Galactic plane between 10 TeV and 1 PeV energies, with the square kilometer array of the Large High Altitude Air Shower Observatory (LHAASO). Diffuse emissions from the inner (15°10  TeV). The energy spectrum in the inner Galaxy regions can be described by a power-law function with an index of -2.99±0.04, which is different from the curved spectrum as expected from hadronic interactions between locally measured cosmic rays and the line-of-sight integrated gas content. Furthermore, the measured flux is higher by a factor of ∼3 than the prediction. A similar spectrum with an index of -2.99±0.07 is found in the outer Galaxy region, and the absolute flux for 10≲E≲60  TeV is again higher than the prediction for hadronic cosmic ray interactions. The latitude distributions of the diffuse emission are consistent with the gas distribution, while the longitude distributions show clear deviation from the gas distribution. The LHAASO measurements imply that either additional emission sources exist or cosmic ray intensities have spatial variations.

[Results analysis of mNGS applied to infectious diseases]

The application of metagenomic second-generation sequencing (mNGS) is shifting from research to clinical laboratories due to rapid technological advances and significant cost reductions. Although many studies and case reports have confirmed that the success of mNGS in improving the prevention, diagnosis, treatment and tracking of infectious diseases, there are still some obstacles that must be overcome. The results of mNGS show all the possible pathogens in the sample, however, in the face of thousands of microbes that can infect humans, it remains challenging to accurately identify the key pathogens. So far, there is no unified interpretation standard for mNGS in clinical practice. This article reviews the interpretation of mNGS results for pathogen infection in different systems, the clinical interpretation and application regulations of mNGS results, and the challenges of mNGS interpretation in pathogen diagnosis.

A tera-electron volt afterglow from a narrow jet in an extremely bright gamma-ray burst

Some gamma-ray bursts (GRBs) have a tera-electron volt (TeV) afterglow, but the early onset of this has not been observed. We report observations with the Large High Altitude Air Shower Observatory of the bright GRB 221009A, which serendipitously occurred within the instrument field of view. More than 64,000 photons >0.2 TeV were detected within the first 3000 seconds. The TeV flux began several minutes after the GRB trigger, then rose to a peak about 10 seconds later. This was followed by a decay phase, which became more rapid ~650 seconds after the peak. We interpret the emission using a model of a relativistic jet with half-opening angle ~0.8°. This is consistent with the core of a structured jet and could explain the high isotropic energy of this GRB.

[A preliminary study on salivary microbiota of patients with laryngopharyngeal reflux]

Objective: To investigate the characteristics of salivary microbiota in patients with laryngopharyngeal reflux (LPR). Methods: A case-control study was applied to enroll 60 patients and healthy subjects who were outpatients of the Department of Otorhinolaryngology Head and Neck Surgery of the Eighth Medical Center of the PLA General Hospital from December 2020 to March 2021, including 35 males and 25 females, aged from 21 to 80 (33.75±11.10) years. Thirty patients with suspected laryngopharyngeal reflux were selected as study group and thirty healthy volunteers without pharyngeal symptoms were selected as control group. Their salivary samples were collected, and the salivary microbiota was detected and analyzed by 16S rDNA sequencing. SPSS 18.0 software was used for statistical analysis. Results: There was no significant difference in the diversity of salivary microbiota between the two groups. At the phylum classification level, the relative abundance of Bacteroidetes in the study group was higher than that in the control group[37.86(31.15, 41.54)% vs 30.24(25.51, 34.18)%,Z=-3.46,P<0.01]. And the relative abundance of Proteobacteria in the study group was lower than that in the control group [15.76(11.81, 20.17)% vs 20.63(13.98, 28.82)%, Z=-1.98,P<0.05]. At the genus level, the relative abundance of Prevotella, Lactobacillus, Parascardovia and Sphingobium in the study group was higher than that in the control group(Z values were-2.92, -2.69, -2.05, -2.31, respectively, P<0.05).And the relative abundance of Streptococcus, Cardiobacterium, Klebsiella and Uruburuella of study group was lower than that of control group(Z values were -2.43, -2.32, -2.17, -2.32, respectively, P<0.05). LEfSe difference analysis showed that there were 39 bacteria with significant differences between the two groups, including Bacteroidetes, Prevotellaceae and Prevotella, which were enriched in the study group, and Streptococcaceae, Streptococcus and other taxa, which were enriched in the control group(P<0.05). Conclusion: The changes of the microflora in the saliva between LPR patients and healthy people suggest that the dysbacteriosis might exist in LPR patients, which may play an important role in the pathogenesis and development of LPR.

Factors influencing herpes zoster vaccination among older people in China: results from a discrete choice experiment

OBJECTIVES

Vaccination is the most effective way to prevent herpes zoster (HZ) and related complications. This study aimed to investigate the preference of HZ vaccine among older people.

STUDY DESIGN

A discrete choice experiment was performed.

METHODS

In total, 178 adults aged ≥50 years were invited to choose between HZ vaccination scenarios using six vaccine attributes. Two equations were used to calculate participants' willingness to pay for the vaccine and their predicted choice probability.

RESULTS

The attributes that significantly influenced participants' vaccine choices were lower cost, higher effectiveness, reduced side-effects and vaccination of others in their surroundings.

CONCLUSIONS

Improving medical insurance coverage or reducing the cost of the HZ vaccine will encourage more people to be vaccinated, resulting in reduced burden of disease among older people.

[Endoscopic transoral approach nasopharyngectomy for petroclival and jugular foramen nasopharyngeal carcinoma]

Objective: To describe a technique of endoscopic transoral approach nasopharyngectomy for petroclival and jugular foramen nasopharyngeal carcinoma, based on anatomic studies and surgeries. Methods: Three dry human skulls and five fresh human cadaver heads were used for anatomic study of a endoscopic transoral approach to expose petroclival and jugular foramen. The anatomical landmarks and the extent of exposure were recorded. Six clinical cases who were treated in Eye & ENT Hospital, Fudan University from June 2020 to April 2022 were used to illustrate the technique and feasibility of this approach and to assess its indications and advantages, including 3 males and 3 females, aged 42 to 69 years old. Descriptive analysis was used in this research. Results: On the basis of the preservation of the internal pterygoid muscle and the external pterygoid muscle, this approach could fully expose the parapharyngeal, petrosal and paraclival segment internal carotid arteries, and safely deal with the lesions of jugular foramen and petroclival region. The 6 patients in our study tolerated the procedure well. Postoperative enhanced MRI showed complete resection of the tumor and no postoperative masticatory dysfunction. Conclusion: Endoscopic transoral approach is a safe, minimally invasive and effective surgical treatment for petroclival and jugular foramen recurrent nasopharyngeal carcinoma.

[Research progression of gene fusion detection technology based on next generation sequencing in tumor companion diagnostics]

Gene fusion is one of the mechanisms that promote tumor development. It is also an important cause for the poor prognosis of patients. The detection of gene fusion is crucial for the recognition of tumor biomarker, cancer subtype classification, and clinical medication guidance. Appropriate methods can help the early diagnosis and avoid ineffective medication. Traditional tests include fluorescence in situ hybridization (FISH), immunohistochemistry (IHC), reverse transcription of PCR (RT-PCR), and next generation sequencing (NGS). The next generation sequencing (NGS) mainly includes: whole genome sequencing (WGS), whole transcriptome sequencing (WTS) and target sequencing (hybridization capture method/amplicon method). In clinical concomitant diagnostic applications, some factors such as operability, time/money costs, and the level of expertise required for data analysis should be considered. This article concludes with a discussion of the technical principles of different detection methods and advantages/limitations. Meanwhile, it provides reference opinions for the detection methods of gene fusion.

[Quantitative analysis of myelofibrosis and its prognostic significance in patients with myelodysplastic syndrome]

Objective: To quantitatively analyze the reticulin fiber intensity density (RFD) in patients with myelodysplastic syndrome (MDS) by using the computer-aided grid point method, and preliminarily explore its correlation with the prognosis of MDS patients. Methods: Bone marrow (BM) slices from 32 primary MDS patients treated in Tongren Hospital Shanghai Jiao Tong University School of Medicine from February 2017 to December 2019 were observed. Images were taken by the optical microscope imaging system after the Gomori staining. The computer grid marking software was developed according to the principle of the mesh micrometer to assess RFD, meanwhile, the artificial semi-quantitative were used to assess the fibrosis of bone marrow. The co-relation between the above two methods was evaluated, and the relationship between RFD and prognosis of MDS patients were further investigated with Cox regression analysis. Results: Of the patients, there were 17 males and 15 females with a median age of 69 years (32-91 years). The RFD quantitatively analyzed by the computer-based method was positively correlated with the myelofibrosis grade by the artificial semi-quantitative analysis (r=0.497, P=0.004). The RFD in patients diagnosed with MDS complicated with excess blasts (MDS-EB) was significantly higher than that in the non-MDS-EB group((9.55%±0.75%) vs (1.71%±0.23%), P<0.001). Cox regression model analysis showed that the RFD of MDS patients had better prognostic value when compared with the artificial semi-quantitative analysis, which was also a poor prognostic factor (RR=1.337, 95%CI: 1.085-1.648, P=0.006). The overall survival (OS) of patients with RFD>5.54% was significantly shorter than that with RFD≤5.54% (P=0.001). The OS of MDS-EB patients with RFD>9.81% was significantly shorter than that in patients with RFD≤9.81% (P=0.003). Conclusion: Abnormal proliferative fibrosis of bone marrow is a potential high-risk factor for poor prognosis of MDS patients.

[Reliability and validity of Stanford Presenteeism Scale (SPS-6) in Chinese occupational population]

Objective: To investigate the reliability and validity of Stanford attendance scale (sps-6) in the study of attendance among professional groups. Methods: In August, 2018, the 1455 employees from 81 workplaces in Beijing, Shanghai, Jiangsu and Guangdong were randomly investigated as the subjects. The reliability and validity of sps-6 were analyzed by using the internal consistency reliability (Cronbach's coefficient) , half split half coefficient, content validity, integration validity, discrimination validity, cluster analysis and structural validity analysis. Results: Cronbach's coefficients of sps-6 scale, working process and work results were 0.692, 0.918 and 0.907, respectively; Guttman of scales and dimensions The split half coefficients were 0.792, 0.803 and 0.794, respectively; Pearson correlation coefficients of the total score of each item and scale were 0.526-0.673 (P<0.01) ; the qualification rate of set validity and differentiation validity were 100%; the results of cluster analysis supported the theoretical basis for the formation of the scale. The general non-standard fitting index (TLI) =0.982, approximate error mean square root mean square (RMSEA) =0.071, comparative fit index (CFI) =0.990, fit goodness index (GFI) =0.987, modified fit goodness index (AGFI) =0.965, Norm fit index (NFI) =0.990. The results showed that the scale had higher structural validity, and the results of sps-6 in the occupational population were (21.36±4.04) , and the distribution was normal (deviation was 0.053, peak was 0.023) . The scores of sps-6 scale were statistically different in various charactoristics of gender, age, education level, marital status, annual income, position, position level and industry (P< 0.01) . Conclusion: Stanford attendance scale has high reliability and validity, and can be applied to the study of attendance in professional groups.

[The incidence of school violence and its relevant factors among senior students of rural primary schools in Guizhou and Anhui Province in 2016]

Objective: To understand the incidence of school violence and its related factors among senior students in rural primary schools in Guizhou and Anhui provinces in 2016. Methods: From September to November 2016, one county was randomly selected from 47 impoverished counties of Guizhou and one county was randomly selected from 18 impoverished counties of Anhui Province by using multi-stage cluster sampling method. A total of 4 schools were randomly selected from primary schools which had more than 70% students with rural resident registration in each selected county, and 3 classes were randomly selected from fifth and sixth grades of each selected school. All students in each selected class were included in this study. A total of 2 521 students were included, and 2 506 valid questionnaires were collected with an effective response rate about 99.4%. Self-designed questionnaires were used to collect data on individual information, family information, and the incidence of school violence with related factors. Multivariable logistic regression was conducted to analyze related factors of school violence. Results: The incidence of violence in rural primary schools was 50.4% (1 264/2 506) in 2016. The number of students who had physical assault, fought or been bullied was 682 (27.2%), 689 (27.5%) and 764 (30.5%), respectively. The results of multivariable logistic regression showed that the OR (95%CI) values of incidence of school violence for male students was 2.13(1.78-2.54) compared with female students; and the OR(95%CI) values of incidence of school violence for students with high peer acceptance, high family intimacy, more physical activity and mother who had education background of junior high school, senior high school, technical secondary school and junior college, bachelor's degree or above were 0.39 (0.26-0.57), 0.47 (0.40-0.57), 0.64 (0.52-0.78), 0.79 (0.66-0.96), and 0.65 (0.46-0.92) compared with those with low peer acceptance, low family intimacy, less physical activity and mother who had primary education and below. Conclusion: The incidence of violence in rural primary schools is not optimistic. Gender, peer acceptance, family intimacy, physical activity and mother education are related to school violence.

[Effectiveness of self-management behavior intervention on type 2 diabetes based on self-determination theory]

OBJECTIVE

To provide autonomy support from three dimensions based on self-determination theory (SDT), i.e. professional support, peer support, family support, and to investigate whether this intervention can improve diabetes self-management behavior and glycemic control of diabetic patients, and to analyze the influencing factors of the effect.

METHODS

Using convenient sampling method, three communities were selected respectively in Beijing. Each community selected health service stations with similar conditions as different intervention groups. The diabetic patients managed by the station who were eligible for inclusion were recruited into this intervention group. The community stations were divided into three groups. The routine intervention group only issued knowledge manuals and conducted health management according to the requirements of basic public health services. Peer support groups were divided into small groups and carried out doctor-led group activities. Based on doctor-led peer support activities, the doctors and peers were trained to provide autonomy support based on self-determination theory, and their family members were trained in the form of manuals to provide autonomy support, forming a concerted support of the three dimensions. Activity processes and materials were also designed based on SDT. The intervention duration was 3 months, and the main evaluation indexes were HbA1c and patients' self-management behaviors, skills, knowledge, and self-efficacy scores.

RESULTS

Before and after the intervention, the HbA1c of routine intervention group were 7.40%±1.37%, 7.30%±1.18%. The HbA1c of peer support group before and after the intervention were 7.33%±1.15% and 7.13%±1.27%. The HbA1c of autonomy support group before and after the intervention were 7.42%±1.22% and 6.78%±0.80%. Before and after the intervention, the self-management score in routine intervention group was 10.54±2.28 and 10.80±2.15, the score in peer support group was 11.09±1.89 and 11.40±1.78, the score in autonomy support group was 10.34±1.99 and 11.10±1.65, respectively. The HbA1c and self-management score increased higher in autonomy support group than in the other two groups. After intervention, the control rate in autonomy support group was higher than in the other two groups. According to the multi-factor analysis, the value of HbA1c after intervention was positively related to the baseline HbA1c, and negatively related to self-management behavior. The value in autonomy support group was higher than in routine intervention group. Baseline self-management behavior, self-efficacy, knowledge, skill, family support, autonomy support, peer support and age were positively correlated with the change of behavior.

CONCLUSION

self-management behavior intervention based on self-determination theory can effectively promote self-management behavior and glycemic control of diabetic patients, and the effect is better than single peer support activities.

Diethylstilbestrol regulates mouse gubernaculum testis cell proliferation via PLC-Ca2+ -CREB pathway

Recent evidence suggested a positive correlation between environmental estrogens (EEs) and high incidence of abnormalities in male urogenital system, but the mechanism remains unclear. Diethylstilbestrol (DES) is a nonsteroidal synthetic estrogen that disrupts the morphology and proliferation of gubernaculum testis cells, but the underlying mechanism is unclear. In this study, mouse gubernaculum testis cells were pretreated with phospholipase C (PLC) inhibitor U-73122 and then treated with DES. The results demonstrated that U-73122 impaired DES-evoked intracellular Ca2+ mobilization in gubernaculum testis cells and inhibited DES-induced proliferation of gubernaculum testis cells. Mechanistically, we found that U-73122 inhibited DES-induced activation of cAMP-response element binding protein (CREB) in gubernaculum testis cells. In conclusion, these data suggest that the effects of DES on mouse gubernaculum testis cells are mediated by PLC-Ca²⁺ -CREB pathway.

SIGNIFICANCE OF THE STUDY

Environmental estrogens remain a serious threat to male reproductive health, and it is important to understand the mechanism by which EEs affect the male productive system. Here we explore potential mechanisms how the proliferation and contractility of gubernaculum testis cells are regulated by diethylstilbestrol. Our findings provide the first evidence that PLC-Ca²⁺ -CREB signalling pathway mediates the nongenomic effects of diethylstilbestrol on gubernaculum testis cells. These findings provide new insight into the role of diethylstilbestrol in the aetiology of male reproductive dysfunction and will help develop better approaches for the prevention and therapy of male reproductive malformation.

[Impacts of DES on the expressions of related genes in the gubernaculums testis of newborn mice]

OBJECTIVE

To investigate the influence of diethylstilbestrol (DES) on the mRNA expressions of the androgen receptor (AR), estrogen receptor α (ERα), proliferating cell nuclear antigen (PCNA), and actin alpha 1 (ACTα1) in the gubernaculums testis of newborn mice and explore their action mechanisms.

METHODS

A total of 140 male Kunming mice were randomly divided into a blank control, a dimethyl sulfoxide (DMSO) control, and 5 experimental groups to be treated subcutaneously with normal saline, DMSO, and DES at 0.02, 0.1, 0.5, 10 and 50 μg per kg of the body weight per day, respectively, at gestation days 9－17. On the first day after birth, the animals were sacrificed and the gubernaculums testis collected for detection of the mRNA expressions of AR, ERα, PCNA and ACTα1 by RT-PCR.

RESULTS

Compared with the DMSO control, the experimental groups, particularly the DES 10 and 50 μg groups, showed significant increases in the mRNA expression of ERα (RE2 = 0.825, P <0.05), but remarkable decreases in those of AR, PCNA and ACTα1 (RA2 = 0.713, RP2 = 0.946, RT2 = 0.960, P <0.01), all in a dose-dependent manner.

CONCLUSIONS

The AR, ERα, PCNA, and ACTα1 mRNA are expressed in the gubernaculum testis of normal newborn mice, and their expression levels may be influenced by intervention with different concentrations of DES during the gestation. Exogenous estrogens may affect the proliferation and contraction of gubernaculum testis cells and consequently the normal development of the testis or even the whole male reproductive system by influencing the metabolism of ER and/or AR.

Diethylstilbestrol affects the expression of GPER in the gubernaculum testis

Recent evidence suggested a positive correlation between environmental estrogens (EEs) and high incidence of abnormalities in male urogenital system. EEs are known to cause the abnormalities of testes development and testicular descent. Diethylstilbestrol (DES) is a nonsteroidal synthetic estrogen that disrupts the morphology and proliferation of gubernacular cells, and its nongenomic effects on gubernaculum testis cells may be mediated by G protein-coupled estrogen receptor (GPER). In this study, we detected the expression of GPER in mouse gubernacular testis and investigated the effects of DES on the expression of GPER in gubernaculum testis cells. RT-PCR analysis revealed that GPER mRNA was expressed in the gubernaculum. GPER protein was detected in the parenchymal cells of the gubernaculum early in development. Furthermore, we demonstrate that GPER inhibitor G15 relieved DES-induced inhibition of GPER expression in gubernaculum testis cell, but ER inhibitor ICI 182780 had the converse effects on DES-induced inhibition of GPER expression in these cells. These data suggest that the effects of DES on mouse gubernaculum testis cells are mediated at least partially by the regulation of GPER expression.

[Diethylstilbestrol affects LGR8 expression in mouse gubernaculum testis]

OBJECTIVE

To investigate the impact of prenatal exposure to diethylstilbestrol (DES) on the specific receptor LGR8 of insulin-like factor 3 (INSL3) in the mouse gubernaculum testis, and that of exoestrogens on descensus testis in mice.

METHODS

A total of 120 pregnant KM mice aged 8 to 10 weeks were assigned to a normal, a blank control and 4 DES groups of equal number, the blank controls injected subcutaneously with dimethyl sulfoxide plus normal saline, and the DES groups with DES at 0.1, 1, 10 and 100 microg/kg body weight, respectively, from embryonic day 9 (ED9) through ED17. Immunohistochemistry and RT-PCR were used to detect the expressions of LGR8 protein and mRNA in the gubernaculum testis of the ED18 fetuses and PND20 (postnatal day 20) offspring of the mice.

RESULTS

Histological analysis showed that the gubernaculum testis of the ED18 fetuses were well developed in both the normal and control groups, with an inner mesenchymal core and muscular outer layer. In contrast, the gubernaculum testis were poorly developed in the experimental groups, morphologically abnormal and without visible dividing line between the mesenchymal tissue and the muscular outer layer. No obvious differences were found in the gubernaculum testis development of the neonates between the normal and experimental groups. Positive immunostaining was seen in the mesenchymal core and muscular outer layer, but mainly in the latter. The expression of LGR8 was weaker in the experimental groups than in the normal group (P < 0.05), but that of LGR8 mRNA was increased in the high-dose (10 and 100 microg/kg) DES groups (P < 0.05). No obvious mutations were observed in the PCR products in any of the experimental groups.

CONCLUSION

Prenatal exposure to diethylstilbestrol affected the expression of LGR8 mRNA in the mouse gubernaculum testis, which suggests that diethylstilbestrol may induce cryptorchidism by interfering with the INSL3-LGR8 signaling system and consequently the development of the gubernaculum testis.

[A morphological study with serial histological slices on the normal and abnormal gubernacula in newborn male mice]

OBJECTIVE

To explore the feasibility of serial slices microscopic histological investigation for the elaborate evaluation of reproductive system malformations.

METHODS

Newborn male mice prenatally exposed to different doses of subcutaneously given diethylstilbestrol (DES) from gestational day 9 to 17 were treated by fixing parts of the abdomen in situ and setting them to transected serial slices. All the slices were stained, studied under the microscope and serially recorded by software. The gubernaculum was morphologically analyzed and its location and size were measured.

RESULTS

Morphologically, the gubernaculum could be identified clearly, its structure inhomogeneous from proximal to distal and dissymmetric from right to left. The environmental estrogen produced different effects on the morphology of the gubernaculum in different parts and most obviously affected its length.

CONCLUSION

Prenatal exposure to environmental estrogen has evident and general effects on the gubernacular development of newborn male mice. The morphological study with serial histological slices gives a precise and systematic evaluation of genital malformations.

[Advances in the endocrine factors affecting the development of gubernaculum testis]

The testicular gubernaculum plays an important role in testicular descent and development. Its differentiation and development are affected by many factors. Androgens, calcitonin gene-related peptide (CGRP), insulin-like factor 3 (INSL3), Müllerian inhibiting substance (MIS), epidermal growth factor (EGF) and environmental estrogens (EEs) are involved in gubernacular development. The effect of CGRP, INSL3 and especially EEs on genital system has been attracted more attention.

[Relationship between insulin like hormone 3 and testicular descent and development]

Testicular descent is an essential step in the course of reproductive system development. The mechanisms involved in the regulation of testis descent is not distinct. Gubernaculum has a very close relationship with testis descent. Maldescent of testis can cause abnormalities of genital system such as testicular underwent (cryptorchidism), dysplasia, tumor, infertility and low sexuality. Recently insulin like hormone 3 is a hotspot of concerning affecting gubernacular development and testicular descent. This article briefly reviews the advances in these aspects.

Effect of prenatal exposure to diethylstilbestrol on gubernacular development in fetal male mice

AIM

To study the effect of prenatal exposure to diethylstilbestrol (DES) and the role of actin and proliferating cell nuclear antigen (PCNA) on testicular gubernaculum development in fetal male Kunming mice.

METHODS

Pregnant mice were randomly assigned to 6 groups and injected with DES subcutaneously from gestational day 9 (E9) to day 17 (E17) at doses of 0, 25, 50, 100, 200 microg.kg-1.d-1 in 0.2 mL dimethyl sulfoxide (DMSO). On E17 they were sacrificed and fetuses quickly removed for fixation. Male fetuses were sliced on serial coronal plane. Histological changes were observed under the light microscope (LM) and ultrastructural changes with the scanning and transmission electron microscopes (SEM and TEM). The expression intensity of actin and PCNA in the gubernacula was quantitated by immunohistochemistry.

RESULTS

The mortality of the fetuses was higher in the DES-treated groups than that in the DMSO and saline controls (P<0.05). Under LM the gubernacula were seen to be poorly developed with smaller bulbs. On SEM the bulbs lose the clear demarcation between the mesenchymal inner core and the muscular outer layer and looked like a small cone instead of the normal cylindrical appearance. On TEM there were some smaller disordered myofibrils and sparse cytoplasmic organelles in the gubernacular muscular cells of the treated groups. The expression intensity of actin and PCNA in the gubernacula was significantly weaker in the treated groups than that in the DMSO and saline controls (P<0.05).

CONCLUSION

DES induces underdevelopment of the gubernacula in a dose-dependent manner in fetal male mice and down regulates the actin and PCNA expression.

[Associated sedation of propofol and midazolam in small dosage and gastroscopy]

OBJECTIVE

To search for a sedative method that is more suitable for gastroscopy.

METHODS

All of patients were randomly divided into control group and experimental group. The experimental group was treated with propofol and midazolam, the control group was treated with propofol alone. The cumulation dosage of propofol, sedative effect, variation of BP and SaO2 were observed in all patient.

RESULTS

The cumulative dosage of propofol in the experimental group was lower than that in the control group [(73.21 +/- 18.67) mg and (117.23 +/- 21.57) mg respectively]; the oblivious degree in the experimental group was higher than that in the control group (95.65% and 80.00%); the onset time and the descendant range of BP and SaO2 were also lower in the experimental than those in the control group. There was not remarkable difference in sedative effect and veriviscont time between the control group and the experimental group.

CONCLUSIONS

In such a rapid operation of gastroscopy, the dosage of propofol in the experimental group is obviously less than that in the control group, while it does not affect the effect of sedation, the diagnose and cure time in gastroscopy room, and has more security and less cost.

Apoptosis in microvascular endothelial cells of perfused rabbit lungs with acute hydrostatic edema

We test the hypothesis that microvascular endothelial cells may undergo apoptosis in response to acute pulmonary venous hypertension. The isolated rabbit lungs were perfused in situ for 4 h with left atrial pressure of 0, 10, or 20 mmHg at a constant blood flow. Edema formation was monitored by lung weight gain. To assay for apoptosis, we performed agarose gel electrophoresis of DNA, in situ nick end labeling of DNA strand breaks, and electron microscopy. We also examined the levels of expression of Bcl-2, a suppressor of apoptosis, in microvascular endothelial cells using an immunohistochemical technique. In a vascular pressure-dependent fashion, we found apoptosis in endothelial cells of alveolar septal capillaries, as well as expression of Bcl-2 in arteriolar and venular endothelial cells. We conclude that acute pulmonary venous hypertension induces apoptosis in capillary endothelial cells but not in arteriolar and venular endothelial cells, suggesting that microvascular endothelial cell apoptosis is dependent on the levels of Bcl-2 expression and influences the formation or resolution of acute hydrostatic lung edema.

Seroprevalence of cytotoxin-associated gene A positive Helicobacter pylori strains in Changle, an area with very high prevalence of gastric cancer in south China

BACKGROUND

Helicobacter pylori, especially the CagA-positive strains, are closely associated with peptic ulcers and gastric cancers. We performed a large scale gastric cancer screening project and examined the prevalence of H. pylori and CagA-positive strains in Changle, China, an area with one of the World's highest gastric cancer mortality. We also compared the prevalence with that in Hong Kong which has one-tenth of the gastric cancer mortality of that in Changle.

METHODS

A total of 2424 subjects in Changle and 523 subjects in Hong Kong had endoscopic examination and venesection. Sera were tested for anti-H. pylori antibody and anti-CagA antibody and correlated with endoscopic findings.

RESULTS

In Changle, 80. 9% of the subjects were H. pylori carriers. Out of 551 carriers, 408 (74%) were positive for anti-CagA antibody. A total of 76% and 87% of the asymptomatic and gastric cancer patients were positive for anti-CagA antibody, respectively (P > 0.05). Compared to Hong Kong, there was a significantly (P < 0.0001) higher prevalence of CagA-positive strains in asymptomatic subjects in Changle (76%) than in Hong Kong (28%), but not in peptic ulcers or gastric cancers.

CONCLUSIONS

Subjects in Changle had a high prevalence of H. pylori infection and a high prevalence of the CagA-positive strains. The contrast in the prevalence of CagA-positive strains, in asymptomatic subjects in two areas with differing gastric cancer mortality, supports the pathogenic role of CagA-positive strains in gastric carcinogenesis.

Differential Helicobacter pylori infection rates in two contrasting gastric cancer risk regions of South China. China Gastric Cancer Study Group

BACKGROUND

Carriers of Helicobacter pylori are believed to have a three- to six-fold increased risk of developing gastric cancer. We have recently conducted a simultaneous cross-sectional population study on the prevalence of H. pylori infection in a cohort of asymptomatic adult volunteers in two contrasting gastric cancer risk regions of South China, Hong Kong and Changle of Fujian. Their mean annual gastric cancer mortality has been approximately 7.5 and 75/100 000 population, respectively, since the beginning of the last decade. The aim of this study was to evaluate if H. pylori prevalence bears any relationship to gastric cancer mortality rates in these two southern regions of China.

METHODS

Sera were obtained from 397 volunteers in Hong Kong. They were tested for anti-H.pylori immunoglobulin (Ig) G antibody by using a commercial enzyme-linked immunosorbent assay (ELISA) kit. Volunteers of Changle (1456) had upper endoscopy examination and were also tested for anti-H. pylori IgG antibody by the same ELISA method.

RESULTS

The overall H. pylori infection prevalence was significantly higher in Changle (80.4%) than in Hong Kong (58.4%; P< 0.01). The high prevalence is associated with more atrophic gastritis. The overall risk of gastric cancer in people of Changle is approximately five-fold that of Hong Kong (adjusted odds ratio 4.9, 95% CI 2.5-9.8).

CONCLUSIONS

It is concluded that the prevalence of H. pylori infection rates bear a direct relationship to gastric cancer mortality rates in these two southern regions of China. Thus, H. pylori most likely plays a significant aetiopathogenetic role in gastric carcinogenesis in subjects living in Changle.

Effects of low-dose Beraprost sodium, a stable prostaglandin I2 analogue, on reperfusion injury to rabbit lungs

We investigated the effects of low-dose Beraprost sodium (BPS), a stable prostaglandin I2 (PGI2) analogue, on microvascular permeability and the plasma concentrations of thromboxane and adenosine 3',5'-cyclic monophosphate (cAMP) in blood-perfused rabbit lungs subjected to ischemia-reperfusion (I/R). After an ischemic insult for 2 h, saline as a vehicle, 3 pmol/L of BPS (BPS-1), 150 to 300 pmol/L of BPS (BPS-2), 900 pmol/L of BPS (BPS-3), or 60 micromol/L of indomethacin (IND) was administered into the reservoir, then the lungs were reperfused and reventilated for 1 h. Vascular permeability was assessed by determining the microvascular filtration coefficient (Kf, ml/min/mm Hg/100 g wet lung). I/R resulted in increases in vascular resistance, Kf, and thromboxane. BPS-2, BPS-3, and IND inhibited the increase in vascular resistance, and BPS-3 and IND attenuated the increases in Kf and thromboxane. BPS-3 increased, but IND decreased, the concentrations of cAMP in the perfusate. Perfusate thromboxane released after reperfusion was significantly correlated with Kf. We conclude that cyclooxygenase products play a critical role in I/R-induced lung vascular injury and that 900 pmol/L of BPS inhibits the production of thromboxane and enhances the permeability barrier via a cAMP-elevating effect. However, vasodilatory action of BPS may exacerbate the reperfused lung injury by increasing the flow through injured capillaries via inhibition of thromboxane-induced vasoconstriction.

[Experimental study on different concentration alcohol humidifying oxygen supply improving hypoxia caused by pulmonary edema]

In order to research the best alcoholic concentration in the humidifying bottle when pneumonedema oxygen inhalation, 32 rabbits, divided into 4 groups, are replicated into pneumonedema models using method of rapid transfusion, and given oxygen inhalation with 20%, 50%, 70%, and 90% alcohol as humidifying agent (shortly called alcoholic oxygen). The results are as follows: using 20% alcohol as humidifying agent, the increasing amplitude of blood PaO2 is 147.30% (P < 0.001), the injury to the pulmonary bronchial mucosa and the wall of pulmonary alveoli is slight; using 50% alcohol, the increasing amplitude of blood PaO2 is 39.46% (P < 0.001), the injury to the parts mentioned above exacerbates and bronchiole cavity mucosa has moderate bleeding; using 70% alcohol, the increasing amplitude of blood PaO2 is 21.97% (P < 0.05), pneumorrhagia occurs; using 90% alcohol, the increasing amplitude of blood PaO2 is 94.46% (P < 0.01), a great number of blood cells aggregate inside the pulmonary alveoli and the bronchiole. This study proves that choosing 20% alcohol as humidifying agent has the best result, and as well, the explanation of the mechanism of alcohol suppressing foam, meaning being able to decrease only the surface tension of the foam inside the pulmonary alveoli, is incomprehensive, and the nature of the material itself forming foam has decisive function.

Survey of 160 centenarians in Shanghai

One hundred and sixty centenarians were discovered and followed up for 7 years (1982-88) in Shanghai. The proportion of centenarians in the population was non-significantly greater in the urban than in the rural area and centenarians were in general increasing in both areas over the years. The factors promoting longevity were good medical care and benevolent attention from family members. Autopsy was performed in eight centenarians revealing the main causes of death as pneumonia and cancer.

RNA-primed initiation sites of DNA replication in the origin region of bacteriophage lambda genome

Using DNA molecules synthesized in the early stage of lambda phage infection, deoxynucleotides at the transition sites from primer RNA to DNA synthesis have been mapped in the 1.5 kbase area of the lambda phage genome containing the genetically defined replication origin (ori lambda). Sites in the 1-strand (the polarity of the 1-strand is 5' to 3' from the left to the right direction of the lambda phage genetic map) were distributed both inside and outside of the ori lambda, whereas the sites in the r-strand (the strand in the opposite polarity) were mainly distributed more than three hundred nucleotides apart from the ori lambda to the right. A CPuPu sequence was found at -12 to -10 region of transition sites of the r- and the 1-strands in the frequency of 80% and 70%, respectively, and over 60% of the CPuPu sequences were CAG. Properties of the transition sites are discussed in relation to the primer synthesis.

The distribution and properties of RNA primed initiation sites of DNA synthesis at the replication origin of Escherichia coli chromosome

RNA-linked DNA molecules were obtained from E. coli dnaCts cells synchronously initiating a new round of chromosome replication. The deoxynucleotides at the transition from primer RNA to DNA were 32P-labeled, and their positions were located on the nucleotide sequence of 1.4 kb genomic region (position -906 to +493) including the oriC and its leftside flanking region. In the r-strand (the counterclockwise strand), many strong transition sites were mapped in the left half portion of the oriC and a few weak sites in the left outside region. In the 1-strand (the clockwise strand), no transition sites were found inside the oriC but many weak sites were found in the left outside region. The results support the initiation mechanism in which the first leading strand synthesis starts with the r-strand counterclockwise from the oriC that is followed by the 1-strand synthesis on the displaced template strand on the left of oriC. Primer RNA molecules attached to the strong r-strand transition sites were only a few residues in length. Properties of the transition sites were discussed.