[Mid- and long-term results of surgical treatment of brachiocephalic Takayasu arteritis]

Objective: To examine the mid - and long-term outcomes of surgical treatment of brachiocephalic Takayasu arteritis. Methods: This is a retrospective case series study. The clinical data of 39 patients,which had been diagnosed as brachiocephalic Takayasu arteritis (244 cases),who underwent surgical treatment,were analyzed between July 2012 to November 2022 at Department of Endoluminal Vascular Surgery, the First Affiliated Hospital of Zhengzhou University. There were 5 males and 34 females, aged (37.9±14.0)years (range:13 to 71 years). Despite medical treatment, the patients suffered severe ischemic symptoms continually and then underwent surgical interventions. Among them, 20 patients underwent endovascular procedures, 11 underwent open surgical procedures, and 8 underwent hybrid procedures. Patients were followed up through outpatient visits at 1, 3, 6 months after surgery and once every year later. Follow-up was conducted until November 2022. Operation status, postoperative complications and re-intervention of patients were recorded and the Kaplan-Meier survival curves were used to analyze postoperative vascular patency rates. Results: All 39 surgeries were successful, with no intraoperative death or serious complications. The follow-up period was (48.8±38.2) months(range:1 to 123 months). Thirty-three patients experienced symptom relief after surgery, and 6 patients required secondary surgical interventions. The patency rates for the endovascular treatment group at 1-, 3-, 5-, and 10-year were 95.0%, 75.2%, 60.2%, and 60.2%, respectively, while the patency rates for open surgery were all 90.9%. In the hybrid surgery group, the patency rates at 1-, 3-, 5-, and 8-year were all 87.5%. Conclusion: For patients with brachiocephalic Takayasu arteritis, choice of an appropriate blood flow revascularization intervention should be based on the patient's condition,and the mid-and long-term outcomes are satisfactory.

[A case of multiple difficult illnesses in a patient with extremely severe burn complicated with type 2 diabetes]

On December 20, 2018, a 40-year-old male patient with extremely severe flame burn was admitted to Guangzhou First People's Hospital. A variety of difficult illnesses occurred simultaneously (refractory hyperglycemia, refractory hypernatremia, and progressive wound deepening) and successively (repeatedly postoperative hypotension, nervous system diseases, and secondary diabetes insipidus). The patient underwent treatments such as anti-shock, reducing blood sugar and blood sodium, scab removing, and gradual skin grafting after admission. Although the hyperglycemia and hypernatremia were basically corrected and the wounds were basically repaired, the patient ultimately died of nervous system diseases and secondary diabetes insipidus 5 months later. Although the cause of the above illnesses can not be fully determined, the targeted treatments to improve clinical symptoms, maintain stable internal environment and physiological function, and accelerate the process of wound repair conducted by the team may provide some experience for the treatment of such severe patients.

[Status of HVPG clinical application in China in 2021]

Objective: The investigation and research on the application status of Hepatic Venous Pressure Gradient (HVPG) is very important to understand the real situation and future development of this technology in China. Methods: This study comprehensively investigated the basic situation of HVPG technology in China, including hospital distribution, hospital level, annual number of cases, catheters used, average cost, indications and existing problems. Results: According to the survey, there were 70 hospitals in China carrying out HVPG technology in 2021, distributed in 28 provinces (autonomous regions and municipalities directly under the central Government). A total of 4 398 cases of HVPG were performed in all the surveyed hospitals in 2021, of which 2 291 cases (52.1%) were tested by HVPG alone. The average cost of HVPG detection was (5 617.2±2 079.4) yuan. 96.3% of the teams completed HVPG detection with balloon method, and most of the teams used thrombectomy balloon catheter (80.3%). Conclusion: Through this investigation, the status of domestic clinical application of HVPG has been clarified, and it has been confirmed that many domestic medical institutions have mastered this technology, but it still needs to continue to promote and popularize HVPG technology in the future.

[Effects of tree species identity and diversity on young tree growth in a south subtropical plantation]

To select the tree species assembly model for improving the productivity in south subtropical plantations, we carried out an experiment following a random block design with eight native tree species across a richness gradient of 1, 2, 4, and 6 species. The effects of tree species diversity and species mixing with different functional identities on the young tree growth were investigated in the 5th year of the experiment. The results showed that tree growth was not positively correlated with tree species richness. The growth of fast-growing tree species (Pinus massoniana and Mytilaria laosensis) in the monoculture was 2.5-4.5 times of the valuable broadleaved tree species (Castanopsis hystrix and Erythrophleum fordii) monoculture. Tree growth was significantly increased by 51.5%-132.8% in the conifer and broadleaved tree species mixing plantations and in the fast-growing and nitrogen fixation tree species mixing plantations, when two tree species or four tree species were mixed. There was no significant difference in tree growth among different tree species mixed types, when six tree species were mixed. The contents of soil nitrogen, phosphorus and organic matter were the main factors affecting tree growth. The results indicated that young tree growth could be improved through the selecting conifer and broadleaved tree species mixing, fast-growing and nitrogen fixation tree species mixing in south subtropical plantations.

[Analysis of diagnosis, treatment and risk classification of blunt thoracic aortic injury]

Objective: Propose a new risk classification system for blunt thoracic aortic injury and explore its treatment strategies. Methods: After the retrospective analysis of clinical data from 68 patients with blunt thoracic aortic injury in the First Affiliated Hospital of Zhengzhou University from November 2016 to October 2020, there were 56 males and 12 females, among these patients, the median age was 45(21-69). According to the degree of aortic injury and the combined injury, the patients were scored for aortic injury, and the risk of the patients were graded into following three types: low-risk group (score ≤ 2 points) 12 cases, intermediate-risk group (3 points ≤ score ≤ 5 points) 41 cases, high-risk group (score ≥ 6 points) 15 cases. Analyzing the effects of treatments received by patients in different grades on the prognosis. Patients were followed up through hospitalization or outpatient clinics at 1, 3, 6, 12 months after surgery and every year thereafter. Results: Of the 68 patients, 21 received non-surgical treatment and 47 received surgical repair, including 6 open surgery and 41 thoracic aortic endovascular repair. There were 16 cases of emergency operation and 31 cases of delayed operation. Twelve low-risk patients were treated with non-surgical treatment, and only 1 patient died of lung infection, with a mortality rate of 8.3% (1/12). There were 8 deaths in 41 moderate-risk patients, with a mortality rate of 19.5% (8/41), and the aortic-related mortality rate was 9.8% (4/41), and the operative mortality rate was 10.8% (4/37). The total mortality of 15 high-risk patients was 40% (6/15), and the aortic-related mortality rate was 30.0% (5/15), and the mortality rate of surgical patients was 10% (1/10). During the follow-up period of 5 to 52 months, no deaths occurred outside the hospital. According to the risk grading, there were significant differences in the aortic-related mortality of each grade (χ²=7.840, P=0.020). During the follow-up of 5-52 months, 1 case had type Ⅰ endoleak, 1 case of cerebral infarction, and 1 case of acute renal failure. Conclusion: According to the patient's degree of aortic injury and combined injury, the risk classification helps to choose the appropriate treatment.

Subcapsular Injection of Ultrasonic Contrast Agent Distinguishes between Benign and Malignant Lymph Node Lesions Exhibiting Homogeneous Enhancement in Intravenous Contrast-Enhanced Ultrasound Images

We aimed to evaluate whether subcapsular injection of ultrasonic contrast agent (UCA) can distinguish between benign and malignant lymph node (LN) lesions exhibiting homogeneous enhancement in intravenous contrast-enhanced ultrasound (CEUS) images. From November 2012 to July 2015, 32 patients with superficial lymphadenopathy exhibiting homogeneous enhancement after intravenous CEUS were enrolled. A small amount of UCA was injected into LNs using a subcapsular approach, and perfusion characteristics were recorded. Using the pathology identified via core needle biopsy as the gold standard, we calculated the sensitivity, specificity and accuracy of the technique in terms of distinguishing between benign and malignant LN lesions. Pathology revealed 23 cases of true benign and 9 cases of true malignant LN lesions; the former included 2 cases of tuberculosis and 21 cases of reactive hyperplasia, and the latter included 7 lymphomas and 2 metastases. Subcapsular CEUS diagnosed 24 benign and 8 malignant LN lesions. Most lymphomas (6 of 7, 85.7%) exhibited heterogeneous perfusion, with lymphatic tract distortion in the absence of interruption. Reactive hyperplasia LNs manifested as diffuse homogeneous or brush-like perfusion from the subcapsular region to the center, without lymphatic tract distortion. Metastatic LNs had lymphatic tract interruptions. The sensitivity, specificity, consistency and positive and negative predictive values were 77.8%, 95.6%, 90.6%, 87.5% and 91.7%, respectively. For LNs exhibiting uniform enhancement in intravenous CEUS imaging, subcapsular CEUS may help to distinguish between benign and malignant lesions. In particular, lymphatic distortion without interruption may specifically indicate a lymphoma.

[Relationship between smoking and the severity of OSA]

Objective:To explore the relationship between smoking and the severity of OSA. Method:There were 719 patients included in the study, who were accompanied by snoring, daytime sleepiness and other symptoms. Laboratory-based polysomnographic variables （including AHI, oxygen desaturation index and microarousal index, etc.）, and anthropometric measurements （including weight, neck circumference, waist circumference, hip circumference etc.） were collected for all participants. The severity of OSA was determined by AHI. No OSA was defined as AHI<5, mild OSA as AHI of 5 to 15，moderate OSA as AHI of >15 to 30, and severe OSA as AHI of >30. Smoking severity was determined by the smoking index （SI）. Light smoke was defined as SI<200, moderate smoke was as SI 200 to 400, and severe smoke as SI>400. Result:There were 138 cases of non-OSA and 581 cases of OSA. There were 381 non-smokers, 279 smokers and 59 quit smokers. The smoking rate of OSA group was significantly higher than that of non-OSA group （41.5% vs. 27.5%,P<0.01）. After excluding 59 quit smokers, the remaining 660 subjects were divided into four groups according to the severity of smoking, then each group was further divided into four groups according to OSA severity. Unadjusted analysis showed that OSA severity positively correlated with smoking severity （r=0.203,P<0.01）. The positive correlation remained significant after further adjustment for age, BMI and waist-hip ratio. In addition, logistic regression analysis showed that compared to non-smokers, the odd ratios for OSA in moderate smokers were 1.72 （95%CI 1.08-2.75） and in severe smokers were 2.68 （95%CI 1.61-4.46）, after adjustment for age, BMI and waist-hip ratio. Conclusion:The severity of smoking significantly correlated with the severity of OSA. There was increased risk of OSA in patients with severe smoke. The correlation was independent of some confounders such as age and obesity.

[Clinical characteristics and management of cervical necrotizing fasciitis]

Objective:To investigate the clinical characteristics and treatment of cervical necrotizing fasciitis. Method:Clinical data of 61 patients were analyzed retrospectively. All patients were underwent surgical debridement and treated with broad-spectrum antibiotics after diagnose. Result:Complications occurred in 14 patients. Fifty-nine patients were cured while 2 patients died. After 3 months or more follow-up, 3 patients accompanied with sequelae of vocal hoarseness, and no patient recurred or died. Conclusion:Early surgical debridement and the use of antibiotics should be taken as soon as possible after diagnosis of cervical necrotizing fasciitis, as well as control of comorbidities and systemic support treatment in order to prevent complications and deaths.

Experimental and Preliminary Clinical Study of Real-Time Registration in Liver Tumors During Respiratory Motion Based on a Multimodality Image Navigation System

Purpose:

To develop a fusion imaging system that combines ultrasound and computed tomography for real-time tumor tracking and to validate the accuracy of performing registration via this approach during a specific breathing phase.

Materials and Methods:

The initial part of the experimental study was performed using iodized oil injection in pig livers and was focused on determining the accuracy of registration. Eight points (A1-4 and B1-4) at different positions and with different target sizes were selected as target points. During respiratory motion, we used our self-designed system to perform the procedure either with (experimental group, E) or without (control group, C) the respiratory monitoring module. The registration errors were then compared between the 2 groups and within group E. The second part of this study was designed as a preliminary clinical study and was performed in 18 patients. Screening was performed to determine the combination of points on the body surface that provided the highest sensitivity to respiratory motion. Registration was performed either with (group E) or without (group C) the respiratory monitoring module. Registration errors were compared between the 2 groups.

Results:

In part 1 of this study, there were fewer registration errors at each point in group E than at the corresponding points in group C (P < .01). In group E, there were more registration errors at points A1 and B1 than at the other points (P < .05). There was no significant difference in registration errors among the remaining points. During part 2 of the study, there was a significant difference in the registration errors between the 2 groups (P < .01).

Conclusions:

Real-time fusion registration is feasible and can be accurately performed during respiratory motions when using this system.

Diabetes mellitus may worsen the prognosis in hepatocellular carcinoma patients undergoing curative microwave ablation

PURPOSE

This study aimed to investigate the outcomes of hepatocellular carcinoma (HCC) patients after curative microwave ablation (MWA) with and without diabetes mellitus (DM).

METHODS

A total of 308 patients with HCC were retrospectively studied from 2005 to 2012 over an 8-year period. They were all successfully treated by MWA. Progression-free survival (PFS) and overall survival (OS) were analyzed according to the status of DM. The presence of other comorbidities and tumor status were studied using multivariate analysis.

RESULTS

Significant differences were observed both for 1-, 3-, 5- year's PFS rates (DM: 63.8, 23.0 and 15.8 vs non-DM: 72.7, 43.6 and 30.8%; p=0.013) and OS rates (DM: 87.3, 75.1 and 49.5% vs non-DM: 97.9, 82.9 and 70.5%; p=0.045) between patients with and without DM. Cox multivariate analysis identified the following factors significantly associated with PFS: (hazard ration (HR): 1.191, 95% CI: 1.051-1,349, p=0.006), AFP (HR:1.000, 95% CI: 1.000-1.000, p=0.022), alcohol abuse (>100g/d vs ≤100g/d, HR:1.579, 95% CI:1.128- 2.212, p=0.008), mean fasting plasma glucose level after initial therapy for HCC(>7.0 / ≤7.0, HR:2.728, 95%CI:1.414- 5.265, p=0.003); and the followings associated with OS:Child-Pugh classification A against B, C (risk 1.692, 95%CI 1.065-2.689, P=0.026), tumor diameter (risk 1.251. 95% CI 1.021-1.534, P=0.031), and AFP (risk 1.000. 95% CI 1.000- 1.000, P=0.000).

CONCLUSION

DM may affect the HCC progression and overall survival in patients undergoing curative MWA. A good control of the glucose levels after ablation may be important for improving the prognosis of HCC.

Electronic States of Nanocrystal Doped with Oxygen and Visible Emission on Black Silicon Prepared by ns-Laser

We fabricated the black silicon (BS) structures by using nanosecond pulsed laser (ns-laser) in vacuum or in oxygen environment. It is interesting that the enhanced visible emission occurs in the photoluminescence (PL) spectra measured at room temperature and at lower temperature on the BS surface after annealing, in which lasing near 600 nm is observed on the BS surface with Purcell cavity structure. It is demonstrated in the PL spectra analysis that the electronic states in the nanocrystal doped with oxygen play a main role in the visible emission on the BS surface. The origin of the visible emission near 400, 560, or 700 nm is univocally revealed in the PL spectra analysis. A visible emission is promising for the development of the white light device on the BS.

Electronic states of defect with impurity and infrared emission on black silicon prepared by an ns-laser

It is found that the optimum annealing temperature is about 1000°C for the infrared emission of defect states at room temperature on black silicon (BS) prepared by using a nanosecond-pulsed laser. In addition, it is observed that the suitable annealing time is 6∼8  min at 1000°C for the emission on the BS. The crystallizing proceeding in annealing on the BS can be used to explain the above annealing effect. It is interesting that the emission band becomes intensive and broader on the BS prepared in oxygen atmosphere than that prepared in vacuum in the analysis of photoluminescence spectra, where the electronic states localized at the defects from D1 to D4 doped with oxygen play an important role in the emission with the broader band which are obviously enhanced in the room temperature.

Lasing with Pumping Levels of Si Nanocrystals on Silicon Wafer

It is reported that the silicon nanocrystals (NCs) are fabricated by using self-assembly growth method with the annealing and the electron beam irradiation processes in the pulsed laser depositing, on which the visible lasing with higher gain (over 130 cm^-1) and the enhanced emission in optical telecommunication window are measured in photoluminescence (PL). It is interesting that the enhanced visible electroluminescence (EL) on silicon nanocrystals (Si-NCs) is obviously observed by the naked eyes, and the light-emitting diode (LED) of the Si-NCs with external quantum efficiency of 20% is made on silicon chip in our laboratory. A four-level system is built for emission model in nanosilicon, in which the PL and EL measurement and transmission electron microscope (TEM) analysis demonstrate that the pumping levels with shorter lifetime from the rising energy of the Si quantum dots due to the quantum confinement effect occur, and the electronic localized states with longer lifetime owing to impurities bonding on Si-NCs surface are formed in the crystallized process to produce the inversion of population for lasing, where the optical gain is generated.

Differential effects of conifer and broadleaf litter inputs on soil organic carbon chemical composition through altered soil microbial community composition

A strategic selection of tree species will shift the type and quality of litter input, and subsequently magnitude and composition of the soil organic carbon (SOC) through soil microbial community. We conducted a manipulative experiment in randomized block design with leaf litter inputs of four native subtropical tree species in a Pinus massoniana plantation in southern China and found that the chemical composition of SOC did not differ significantly among treatments until after 28 months of the experiment. Contrasting leaf litter inputs had significant impacts on the amounts of total microbial, Gram-positive bacterial, and actinomycic PLFAs, but not on the amounts of total bacterial, Gram-negative bacterial, and fungal PLFAs. There were significant differences in alkyl/O-alkyl C in soils among the leaf litter input treatments, but no apparent differences in the proportions of chemical compositions (alkyl, O-alkyl, aromatic, and carbonyl C) in SOC. Soil alkyl/O-alkyl C was significantly related to the amounts of total microbial, and Gram-positive bacterial PLFAs, but not to the chemical compositions of leaf litter. Our findings suggest that changes in forest leaf litter inputs could result in changes in chemical stability of SOC through the altered microbial community composition.

Emission of direct-gap band in germanium with Ge-GeSn layers on one-dimensional structure

In our experiment, it was observed that the emission of direct-gap band in germanium with Ge-GeSn layers on one-dimensional (1D) structure. The results of experiment and calculation demonstrate that the uniaxial tensile strain in the (111) and (110) direction can efficiently transform Ge to a direct bandgap material with the bandgap energy useful for technological application. It is interested that under the tensile strain from Ge-GeSn layers on 1D structure in which the uniaxial strain could be obtained by curved layer (CL) effect, the two bandgaps E_Γg and E_Lg in the (111) direction become nearly equal at 0.83 eV related to the emission of direct-gap band near 1500 nm in the experiments. It is discovered that the red-shift of the peaks from 1500 nm to 1600 nm occurs with change of the uniaxial tensile strain, which proves that the peaks come from the emission of direct-gap band.

Graphene Oxide Based Nanocarrier Combined with a pH-Sensitive Tracer: A Vehicle for Concurrent pH Sensing and pH-Responsive Oligonucleotide Delivery

We chemically tuned the oxidation status of graphene oxide (GO) and constructed a GO-based nanoplatform combined with a pH-sensitive fluorescence tracer that is designed for both pH sensing and pH-responsive drug delivery. A series of GOs oxidized to distinct degrees were examined to optimize the adsorption of the model drug, poly dT30. We determined that highly oxidized GO was a superior drug-carrier candidate in vitro when compared to GOs oxidized to lesser degrees. In the cell experiment, the synthesized pH-sensitive rhodamine dye was first applied to monitor cellular pH; under acidic conditions, protonated rhodamine fluoresces at 588 nm (λex=561 nm). When the dT30-GO nanocarrier was introduced into cells, a rhodamine-triggered competition reaction occurred, and this led to the release of the oligonucleotides and the quenching of rhodamine fluorescence by GO. Our results indicate high drug loading (FAM-dT30/GO=25/50 μg/mL) and rapid cellular uptake (<0.5 h) of the nanocarrier which can potentially be used for targeted RNAi delivery to the acidic milieu of tumors.

Magic electron affection in preparation process of silicon nanocrystal

It is very interesting that magic electron affection promotes growth of nanocrystals due to nanoscale characteristics of electronic de Broglie wave which produces resonance to transfer energy to atoms. In our experiment, it was observed that silicon nanocrystals rapidly grow with irradiation of electron beam on amorphous silicon film prepared by pulsed laser deposition (PLD), and silicon nanocrystals almost occur in sphere shape on smaller nanocrystals with less irradiation time of electron beam. In the process, it was investigated that condensed structures of silicon nanocrystals are changed with different impurity atoms in silicon film, in which localized states emission was observed. Through electron beam irradiation for 15 min on amorphous Si film doped with oxygen impurity atoms by PLD process, enhanced photoluminescence emission peaks are observed in visible light. And electroluminescence emission is manipulated into the optical communication window on the bigger Si-Yb-Er nanocrystals after irradiation of electron beam for 30 min.

[Soil microbial community structure of monoculture and mixed plantation stands of native tree species in south subtropical China]

The effects of three plantation stands, Erythrophleumf ordii (EF), Pinus massoniana (PM), and their mixed plantation (MP), on soil microbial biomass and microbial community structure in south subtropical China were studied by the method of phospholipid fatty acids (PLFAs) analysis. The results showed that the amounts of microbial total PLFAs and PLFAs of each microbial group in these three plantation stand soils were significantly higher in dry season than in rainy season. In dry season, the amounts of microbial total PLFAs, bacteria PLFAs, fungi PLFAs, and actinomycetes PLFAs were the highest in the PM soil, moderate in the MP soil, and the lowest in the EF soil. But in rainy season, the amounts of microbial total PLFAs, bacteria PLFAs, fungi PLFAs, and arbuscular mycorrhizal fungi (AMF) PLFAs in the EF soil were higher than in the MP soil, and were significantly higher than in the PM soil. Principal component analysis (PCA) indicated that the variations in soil microbial community structure composition were affected by both plantation types and seasons. Redundancy analysis (RDA) of soil microbial community structure and environmental factors showed that soil temperature and moisture, pH, total nitrogen content, and ammonium nitrogen content had significant correlations with PLFA signatures. In addition, the ratio of fungi PLFAs to bacteria PLFAs in the MP soil was the highest among the three stand soils within the whole year, indicating that mixed plantation stands could facilitate the stability of the soil ecosystem.

miR-34a targets the inhibin beta B gene, promoting granulosa cell apoptosis in the porcine ovary

During ovarian follicular growth and development, only a few follicles actually ovulate. Recently, it was found that follicular atresia is triggered by granulosa cell apoptosis, but the molecular mechanism of follicular atresia was not understood. Using flow cytometry, we found that miR-34a promotes granulosa cell apoptosis in pig ovarian follicles. In addition, inhibin beta B was found to be a miR-34a target gene, based on luciferase reporter assays, quantitative RT-PCR and Western blotting. Taken together, our data indicate that miR-34a plays an important role in granulosa cell apoptosis by targeting the INHBB gene in the porcine ovary.

A coumarin-based sensitive and selective fluorescent sensor for copper(ii) ions

A new coumarin-derived fluorescent probe (1) exhibited significant fluorescence quenching in the presence of Cu²⁺ ions.

Hypochlorous acid turn-on boron dipyrromethene probe based on oxidation of methyl phenyl sulfide

A boron dipyrromethene (BODIPY)-based fluorometric probe, HCS, has been successfully developed for the highly sensitive and selective detection of hypochlorous acid (HOCl). The probe is based on the specific HOCl-promoted oxidation of methyl phenyl sulfide. The reaction is accompanied by a 160-fold increase in the fluorescent quantum yield (from 0.003 to 0.480). The fluorescent turn-on mechanism is accomplished by suppression of photoinduced electron transfer (PET) from the methyl phenyl sulfide group to BODIPY. The fluorescence intensity of the reaction between HOCl and HCS shows a good linearity in the HOCl concentration range 1-10 μM. The detection limit is 23.7 nM (S/N=3). In addition, confocal fluorescence microscopy imaging using RAW264.7 macrophages demonstrates that the HCS probe could be an efficient fluorescent detector for HOCl in living cells.

[Characteristics of soil microbial biomass and community composition in three types of plantations in southern subtropical area of China]

By using fumigation-extraction method and phospholipid fatty acids (PLFAs) analysis, this paper studied the characteristics of soil microbial biomass and community composition in the Erythrophleum fordii, Castanopsis hystrix, and Pinus massoniana plantations in south subtropical China. The soil microbial biomass, total PLFAs, bacterial PLFAs, and fungal PLFAs in the plantations were significantly affected by the plantation type and season, and the soil microbial biomass, total PLFAs, and individual PLFA signatures were higher in dry season than in rainy season. The C. hystrix plantation had the highest soil microbial biomass carbon and total PLFAs, while the E. fordii plantation had the highest soil microbial biomass nitrogen. There was a significant positive correlation between the soil pH and arbuscular mycorrhizal fungal (AMF) PLFA (16:1omega5c). The soil total PLFAs, gram-positive bacterial PLFAs, saprophytic fungal PLFA (18:2omega6,9c), and the ratio of gram-positive to gram-negative bacterial PLFAs were significantly positively correlated with soil organic carbon, total nitrogen, and total phosphorus, suggesting that the soil organic carbon, total nitrogen, and total phosphorus contents were the most important nutrient factors affecting the numbers and types of the soil microorganisms. In addition, the ectomycorrhizae fungal PLFA (18:1omega9c) and AMF PLFA were significantly correlated with the soil C/N ratio.

Association between CASP-8 gene polymorphisms and cancer risk in some Asian population based on a HuGE review and meta-analysis

Genetic variation in the CASP-8 gene reportedly can increase cancer susceptibility by regulating tumor cell proliferation and apoptosis. Several studies have investigated this possibility; however, the conclusions remain controversial. We made a Human Genome Epidemiology (HuGE) review and did a meta-analysis to explore the association between CASP-8 gene polymorphisms and cancer risk in Asian populations. Based on the inclusion criteria, 12 case-control studies comprising 7720 cancer cases and 9404 healthy controls were retrieved. Meta-analysis results showed that the rs3834129*del allele/carrier were associated with decreased risk of cancer in Asian populations [del allele: odd ratio (OR) = 0.79, 95% confidence interval (95%CI) = 0.75-0.83, P < 0.001; del carrier: OR = 0.77, 95%CI = 0.72-0.82, P < 0.001]. Subgroup analysis showed that the rs3834129*del allele/carrier are protective factors for cancer risk in Chinese populations (del allele: OR = 0.77, 95%CI = 0.73-0.81, P < 0.001; del carrier: OR = 0.75, 95%CI = 0.70-0.80, P < 0.001), but not in Indian and Korean populations. Furthermore, the rs6704688*T allele/carrier, rs3769827*C allele/carrier, rs3769825*C allele/carrier were associated with decreased risk of cancer in Asian populations (all P < 0.05). While the rs7608692*A allele was associated with increased risk of cancer risk in Asian populations (OR = 1.35, 95%CI = 1.02-1.78, P = 0.03). There was also no significant association between rs3769818, rs13030042, rs13030042, rs1045494, rs1045494, rs2823, or rs113686495, and cancer risk in Asian populations (all P > 0.05). This meta-analysis suggests that the rs3834129*del allele/ carrier, rs6704688*T allele/carrier, rs3769827*C allele/carrier, and rs3769825*C allele/carrier might be protective factors for cancer risk in Asian populations, while the rs7608692*A allele might be a risk factor for cancer risk in Asian populations.

Hypochlorous acid turn-on fluorescent probe based on oxidation of diphenyl selenide

A BODIPY-based fluorescent probe, HCSe, has been successfully developed for the rapid detection of hypochlorous acid based on the specific HOCl-promoted oxidation of diphenyl selenide in response to the amount of HOCl. Confocal fluorescence microscopy imaging using RAW264.7 cells showed that the new probe HCSe could be used as an effective fluorescent probe for detecting HOCl in living cells.

[Research advances in simulating land water-carbon coupling]

The increasing demand of adaptive management of land, forest, and water resources under the background of global change and water resources crisis has promoted the comprehensive study of coupling ecosystem water and carbon cycles and their restrictive relations. To construct the water-carbon coupling model and to approach the ecosystem water-carbon balance and its interactive response mechanisms under climate change at multiple spatiotemporal scales is nowadays a major concern. After reviewing the coupling relationships of water and carbon at various scales, this paper explored the implications and estimation methods of the key processes and related parameters of water-carbon coupling, the construction of evapotranspiration model at large scale based on RS, and the importance of this model in water-carbon coupling researches. The applications of assimilative multivariate data in water-carbon coupling researches under future climate change scenarios were also prospected.

[Characteristics of carbon storage and sequestration in different age beech (Castanopsis hystrix) plantations in south subtropical area of China]

To transform large area pure conifer plantations by planting indigenous and valuable broad-leaved tree species has been advocated as an effective close-to-nature forest management in sub-tropical China. Taking the 10-, 20- and 27-year-old Castanopsis hystrix plantations in Guangxi of South China as test objects and by the methods of plot investigation and biomass measurement, this paper studied the carbon content in different plant organs, litter layers, and soil layers and the carbon storage and its allocation in tree layer, litter layer and soil layer. For the test plantations, the carbon content in different C. hystrix organs ranged from 49.7% to 57.9%, and that in litter layer was 40.8%-50.5%, being higher in fresh litter layer than in semi-decomposed litter layer. The carbon storage in the soil profiles (0-60 cm) increased with plantation age but decreased with soil depth. The total carbon storage in the 10-, 20- and 27-year-old plantations was 182. 42, 234.75 and 269. 75 t x hm(-2), respectively, among which, tree layer, litter layer and soil layer occupied 19.8%, 32.0% and 32.8%, 1.5%, 1.6% and 1.3%, and 78.7%, 66.4% and 65.9%, respectively. The annual net carbon sequestration of the 10-, 20- and 27-year-old plantations was 4.70, 5.64 and 5.18 t x hm(-2), respectively. It was considered that C. hystrix had a high capability in carbon sequestration, being able to be an ideal tree species for multi-purpose forest management with large and valuable timber production.

[Regeneration characteristics of woody plant seedlings in typical secondary forests in Qinling Mountains]

By using sampling plot method, an investigation was conducted on the regeneration characteristics of woody plant seedlings in five kinds of typical secondary forests (Pinus tabulaeformis, Quercus valiena var. acuteserrata, Betula albo-sinensis, Picea asperata, and Pinus armandii) in Qinling Mountains. There was an obvious species differentiation of woody plant seedlings and saplings in the forests. Except for Q. valiena var. acuteserrata and P. armandii forests, the similarity coefficient of the seedlings and saplings species in the forests was lower. The seedlings and saplings quantity, species richness index, Simpson dominance index, and evenness index were higher in P. tabulaeformis and Q. valiena var. acuteserrata forests, the lowest in B. albo-sinensis forest, and basically the same in P. asperata and P. armandii forests. The percentages of the seedlings and saplings in the five forests had significant differences (P < 0.05). Except in B. albo-sinensis forest where the percentage of the saplings was higher, the percentage of the seedlings in the other stands was larger, and in the order of P. asperata forest > P. tabulaeformis forest > Q. valiena var. acuteserrata forest > P. armandii forest, respectively. The sprouting percentage of the seedlings in different forests had significant difference (P < 0.05), and was in the sequence of P. armandii forest > P. asperata forest > B. albo-sinensis forest > Q. valiena var. acuteserrata forest > P. tabulaeformis forest. In Q. valiena var. acuteserrata and P. tabulaeformis forests, the percentage of tree seedlings was the highest, occupying 68% and 51.4% of the total number of woody seedlings, respectively, and their communities were in the medium succession period, with a stronger persistent regeneration capability; in P. asperata and P. armandii forests, the percentage of tree seedlings was 40% and 15%, respectively, and their communities were in the late succession period, with a rather poor regeneration capability; while in B. albo-sinensis forest, the seedlings were difficult to develop into saplings, and thus, its continuous persistent regeneration capability was lack.

[Effects of altitudinal gradient on Salix atopantha foliar delta13C]

In 2010, measurements were conducted on the foliar delta13C, photosynthesis, CO2 diffusive conductivity, nitrogen content, photosynthetic nitrogen use efficiency (PNUE), and special leaf area (SLA) of Salix atopantha at different altitudes (2350 m, 2700 m, 3150 m, and 3530 m) in Wolong Natural Reserve. With the increase of altitude, the foliar nitrogen content (especially the nitrogen content per unit leaf area, N(area)) and the PNUE increased, and the foliar delta13C had a significant increase, with an increment of 1.4 per thousand per 1000 m altitude. The stomatal and mesophyll CO2 diffusion conductance also increased with increasing altitude, which had definite negative effect on the increase of foliar delta13C, but the effect was not strong enough. Comparing with CO2 diffusion conductance, carboxylation capacity was a more important factor limiting the P(c)/P(a), and even, the foliar delta13C. At altitude 2350-2700 m, air temperature was the main factor affecting the allocation of nitrogen in S. atopantha photosynthetic system, whereas at altitude 2700-3530 m, light could be the main affecting factor. No significant difference was observed in the SLA at different altitudes.

[Effect of opening degree regulation on diameter and height increment and aboveground biomass of Korean pine trees planted under secondary forest]

Taking mixed forest of artifical Pinus koraiensis and natural broad-leaved trees as test material, among which the P. koraiensis was 15 (stage I) and 22 (stage II) years old respectively, and was in the same succession layer, the height and diameter increment during 4 years experimental period and the aboveground biomass (AGB) at the 4th experimental year for P. koraiensis were measured in the opening degree (K = 1.0, 1.5, 2.0) regulation experiment. The periodic increment of basal diameter (BD)/diameter at breast height (DBH), tree height and AGB of P. koraiensis trees were highest in the opening degree K = 1.0 treatment. The opening degree K = 1.5 and K = 2.0 treatments promoted the annual increment of P. koraiensis, with the effect increased along with the experimental period elongation and approached or exceeded that of K = 1.0 treatment. The stem biomass proportion of P. koraiensis trees was significantly higher in K = 1.0 treatment than that in the other treatments and the control in stage I, but no significant difference among treatments was found in stage II. The ratio of branch to needle biomass in all opening degree treatments was also significantly higher than that in control in stage I, but no significant difference in stage II. The proportion and distribution of needles in different ages differed in the two stages. It was concluded that opening degrees of 1.0-2.0 were all suitable for the growth of P. koraiensis of 15-22 years old trees planted under secondary forest.

[Correlation analysis on normalized difference vegetation index (NDVI) of different vegetations and climatic factors in Southwest China]

Based on the 1982-2006 NDVI remote sensing data and meteorological data of Southwest China, and by using GIS technology, this paper interpolated and extracted the mean annual temperature, annual precipitation, and drought index in the region, and analyzed the correlations of the annual variation of NDVI in different vegetation types (marsh, shrub, bush, grassland, meadow, coniferous forest, broad-leaved forest, alpine vegetation, and cultural vegetation) with corresponding climatic factors. In 1982-2006, the NDVI, mean annual temperature, and annual precipitation had an overall increasing trend, and the drought index decreased. Particularly, the upward trend of mean annual temperature was statistically significant. Among the nine vegetation types, the NDVI of bush and mash decreased, and the downward trend was significant for bush. The NDVI of the other seven vegetation types increased, and the upward trend was significant for coniferous forest, meadow, and alpine vegetation, and extremely significant for shrub. The mean annual temperature in the areas with all the nine vegetation types increased significantly, while the annual precipitation had no significant change. The drought index in the areas with marsh, bush, and cultural vegetation presented an increasing trend, that in the areas with meadow and alpine vegetation decreased significantly, and this index in the areas with other four vegetation types had an unobvious decreasing trend. The NDVI of shrub and coniferous forest had a significantly positive correlation with mean annual temperature, and that of shrub and meadow had significantly negative correlation with drought index. Under the conditions of the other two climatic factors unchanged, the NDVI of coniferous forest, broad-leaved forest, and alpine vegetation showed the strongest correlation with mean annual temperature, that of grass showed the strongest correlation with annual precipitation, and the NDVI of mash, shrub, grass, meadow, and cultural vegetation showed the strongest correlation with drought index. There existed definite correlations among the climatic factors. If the correlations among the climatic factors were ignored, the significant level of the correlations between NDVI and climatic factors would be somewhat reduced.

Correlation of peripheral blood Vα24 NK T cell count with the severity of hepatic injury in patients with chronic hepatitis B virus infection

AIM: To investigate the changes in the number of Vα24 natural killer (NK) T cells in peripheral blood and its possible correlation with the severity of hepatic injury in patients with chronic hepatitis B virus (HBV) infection.

METHODS: Twenty-six patients with chronic hepatitis B (CHB), 9 patients with liver cirrhosis (LC), 8 patients with acute-on-chronic liver failure (ACLF), and 7 normal controls (NCs) were included in the study. The percentage of Vα24 NK T cells in total peripheral blood T lymphocytes was determined by flow cytometry.

RESULTS: The percentages of Vα24 NKT cells in patients with CHB and ACLF were significantly lower than that in NCs (0.8012% ± 0.2979% and 0.4638% ± 0.2244% vs 1.1114% ± 0.3546%, respectively, both P < 0.05). The percentage of Vα24 NK T cells had a significant positive correlation with prothrombin time (PT) and a significant negative correlation with total bilirubin (TB), but had no significant correlations with serum alanine aminotransferase (ALT) and HBV DNA level.

CONCLUSION: The percentage of Vα24 NK T cells in peripheral blood decreases with the aggravation of hepatic injury in patients with chronic HBV infection, implying that Vα24 NKT cells play an important role in the pathogenesis of chronic hepatitis B.

[Effects of Pinus massoniana plantation stand density on understory vegetation and soil properties]

By using plot investigation and sampling analysis methods, the understory vegetation and soil properties of Pinus massoniana plantations with different stand density in subtropical area were studied in Daqingshan, Guangxi Province. In the P. massoniana plantations after 14-year natural growth, the understory species diversity index of shrub layer increased with the increase of stand density from 1050 trees x hm(-2) to 1800 trees x hm(-2), but decreased when the stand density further increased to 2250 trees x hm(-2). Herb species diversity index was not sensitive to the stand density change. With increasing stand density, shrub biomass had the same variation trend as that of shrub species diversity index, while herb biomass decreased with increasing stand density. Significant differences (P < 0.05) were observed in the soil (0-20 cm) physical and chemical properties between the plantations with different stand density. The soil nutrient contents except those of total P and available K and P had the same variation trend with that of the understory species diversity index of shrub layer. Soil available K and P contents fluctuated with stand density, whereas soil total P content was higher when the stand density was 2100 trees x hm(-2). In the plantations with moderate stand density (1800 trees x hm(-2)) , soil water-holding capacity and soil porosity were higher, and soil bulk density was lower.

[Spatial patterns of dominant tree species in sub-alpine Betula-Abies forest in West Sichuan of China]

Based on the investigation in a 4 hm2 Betula-Abies forest plot in sub-alpine area in West Sichuan of China, and by using point pattern analysis method in terms of O-ring statistics, the spatial patterns of dominant species Betula albo-sinensis and Abies faxoniana in different age classes in study area were analyzed, and the intra- and inter-species associations between these age classes were studied. B. albo-sinensis had a unimodal distribution of its DBH frequency, indicating a declining population, while A. faxoniana had a reverse J-shaped pattern, showing an increasing population. All the big trees of B. albo-sinensis and A. faxoniana were spatially in random at all scales, while the medium age and small trees were spatially clumped at small scales and tended to be randomly or evenly distributed with increasing spatial scale. The maximum aggregation degree decreased with increasing age class. Spatial association mainly occurred at small scales. A. faxoniana generally showed positive intra-specific association, while B. albo-sinensis generally showed negative intra-specific association. For the two populations, big and small trees had no significant spatial association, but middle age trees had negative spatial association. Negative inter-specific associations of the two populations were commonly found in different age classes. The larger the difference of age class, the stronger the negative inter-specific association.

[Carbon storage and its allocation in mixed alder-cypress plantations at different age stages]

The 10-, 15-, 20- and 25-year-old mixed alder (Alnus cremastogyne)-cypress (Cupressus funebris) plantations and the 30-year-old pure cypress plantation succeeded from mixed alder-cypress plantation in the hilly area of central Sichuan Basin were chosen as test objects to study the dynamic changes and allocation patterns of their carbon storage. The results showed that the vegetation carbon storage in mixed alder-cypress plantations increased continually from the age stage of 10- to 30-year, and reached 52.40 t x hm(-2) at the age stage of 30-year. The vegetation carbon storage of arbor layer at each age stage was more than 85.59% of the total, and the soil carbon storage within 0-40 cm layer increased significantly (P < 0.05) from the age stage of 10- to 15-year, with the maximum (84.79 t x hm(-2)) at the age stage of 15-year, but decreased significantly (P < 0.05) from the age stage of 15- to 25-year and tended to stable from the age stage of 25- to 30-year (P > 0.05). The carbon storage of the mixed alder-cypress plantations increased significantly from the age stage of 10- to 15-year, with the maximum (118.13 t x hm(-2)) at the age stage of 15-year, but declined from the age stage of 15- to 25-year while increased slightly from the age stage of 25- to 30-year. The proportion of vegetation carbon storage increased continually from the age stage of 10- to 30-year, whereas that of soil carbon storage was in adverse. Comparing with other types of plantations in China, mixed alder-cypress plantation had a lower storage of carbon.

Seasonal variation and correlation with environmental factors of photosynthesis and water use efficiency of Juglans regia and Ziziphus jujuba

Both the photosynthetic light curves and CO(2) curves of Juglans regia L. and Ziziphus jujuba Mill. var. spinosa in three seasons were measured using a LI-6400 portable photosynthesis system. The maximal net photosynthetic rate (A(max)), apparent quantum efficiency(phi), maximal carboxylation rate (V(cmax)) and water use efficiency (WUE) of the two species were calculated based on the curves. The results showed that A(max) of J. regia reached its maximum at the late-season, while the highest values of A(max) of Z. jujuba occurred at the mid-season. The A(max) of J. regia was more affected by relative humidity (RH) of the atmosphere, while that of Z. jujuba was more affected by the air temperature. Light saturation point (LSP) and Light compensation point (LCP) of J. regia had a higher correlation with RH of the atmosphere, those of Z. jujuba, however, had a higher correlation with air temperature. V(cmax) of both J. regia and Z. jujuba had negative correlation with RH of the atmosphere. WUE of J. regia would decrease with the rise of the air temperature while that of Z. jujuba increased. Thus it could be seen that RH, temperature and soil moisture had main effect on photosynthesis and WUE of J. regia and Z. jujuba. Incorporating data on the physiological differences among tree species into forest carbon models will greatly improve our ability to predict alterations to the forest carbon budgets under various environmental scenarios such as global climate change, or with differing species composition.

Effects of diets supplemented with organic acids and nucleotides on growth, immune responses and digestive tract development in weaned pigs

Sixty-eight (Experiment 1, 46 days feeding) and sixteen (Experiment 2, 21 days feeding) 21-days-old weaned pigs were allotted to four dietary treatments including control, 0.6% organic acids (OA), 0.1% nucleotides (NA) and 0.6% OA plus 0.1% NA for determining the dietary effects. In Experiment 1, OA enhanced peripheral blood mononuclear cells proliferation on day 28 and 46. The plasma immunoglobulin (Ig) A level was elevated by OA (p < 0.06) and NA (p < 0.07), respectively. In Experiment 2, NA increased plasma IgM level, and had an interactive effect with OA on ileal Peyer's patches and mesenteric lymph node lymphocyte proliferation, bile and plasma IgA levels, and jejunal crypt depth. NA elevated gastric pepsin and jejunal alkaline phosphatase activities, however, decreased ileal aminopeptidase N, sucrase or maltase activity. These results suggest that OA and NA have synergistically enhanced the gut-associated lymphocyte responses and NA modulates the digestive tract development of weaned pigs.

[Quantitative analysis of different restoration stages during natural succession processes of subalpine dark brown coniferous forests in western Sichuan, China]

By adopting space as a substitute for time, and based on the approaches of inter-specific association, PCA and optimal division, the restoration stages of various secondary forest communities originated from the natural succession processes of bamboo-dark brown coniferous and moss-dark brown coniferous old-growth forests after clear-cut were quantified at different temporal series (20, 30, 30, 40, 50 and 160-200 years). The results showed that Betula albo-sinensis, Salix rehderiana, Acer mono, A. laxiflorum, Prunus tatsienensis, Hydrangea xanthoneura, Tilia chinensis and Salix dolia were the declining species groups with progressive restoration processes from secondary forest to mature moss and bamboo-dark brown coniferous forests, Sorbus hupehensis, S. koehneana and P. pilosiuscula were the transient species groups, and Abies faxoniana, Picea purpurea, Tsuga chinensis and P. wilsonii were the progressive species groups. During the period of 20-40 years restoration, the secondary forests were dominated by broad-leaved tree species, such as B. albo-sinensis, and the main forest types were moss--B. albo-sinensis forest and bamboo--B. albo-sinensis forest. Through 50 years natural succession, the secondary forests turned into conifer/broad-leaved mixed forest dominated by B. albo-sinensis and A. faxoniana, and the main forest types were moss--B. albo-sinensis--A. faxoniana forest and bamboo--B. albo-sinensis--A. faxoniana forest. The remained 160-200 years old coniferous forests without cutting were dominated by old-growth stage A. faxoniana, and the main forest types were moss--A. faxoniana forest and bamboo--A. faxoniana forest.

Melatonin reduced volume of cerebral infarct induced by photothrombosis in wild-type mice, not in Cyclooxygenase-1 gene knockout mice

Cyclooxygenase (COX) is crucial in inflammation and plays important role in cerebral ischemia. Antiinflammatory effects of melatonin have been verified in previous studies. In this study, cerebral blood flow (CBF) was monitored during operation, infarct volume (IFV) was determined with 5-triphenyltetrazolium chloride (TTC) staining and MR image, and neurological functions were evaluated with turn in an alley and fall pole test in both COX1-gene knockout and wide-type mice with or without melatonin administration 3 days after photothrombosis. CBF reduction, IFV and neurological deficits were not significantly different in COX-1 wild-type and COX-1 knockout mice. Melatonin (15 mg/kg) intraperitoneal injection decreased the CBF reduction, IFV and the latency to turn in an alley in COX-1 wide-type mice, whereas the neuroprotective effect of melatonin was attenuated in COX-1 knockout mice. We concluded that melatonin reduced susceptibility to photothrombotic stroke. COX-1 gene knockout does not alter the susceptibility to cerebral ischemia caused by photothrombosis. COX-1 plays an important role in the pathway of the protection of melatonin.

Using independent component analysis to research heart rate variability

Independent component analysis (ICA) and neural networks were used to extract sub-signals of heart rate variability (HRV). Electrocardiogram (ECG) recording was consisted of six minutes when the volunteer was lying and another six minutes when the volunteer was standing. HRV was extracted from ECG. According to time-delay, HRV was divided into five groups as mixed signals. ICA and neural networks reconstructed five signals into two groups. Results showed that one group signal component centralized in low frequency (called IC1); the other did in high frequency (called IC2). The power of IC1 was significantly increased (P<0.05) and the ratio of IC1 to total power was significantly increased (P<0.01) from lying to standing. Comparing the two postural results, it shows that IC1 may express sympathetic activity, and IC2 represents parasympathetic activity. Sympathetic and parasympathetic nervous function can be evaluated respectively and quantificationally by data and graphs from the two decomposed components. Key word: Neural networks, Independent component analysis, Heart rate variability, Autonomic nervous system.

[A case-control study on the risk factors for preterm delivery]

The risk factors for preterm delivery were analyzed with 1:2 matched case-control study by conditional logistic regression analysis. The result showed that the main risk factors for preterm delivery were neuroticism scores, premature rupture of the membranes, husband's smoking frequency during the third trimester of pregnancy, pregnancy induced hypertension, working strength and first-trimester vaginal bleeding. It is indicated that an examination before delivery and gaining weight during pregnancy are helpful to decrease the occurrence of preterm delivery.

Hemispheric sensitivity to grammatical cues: evidence for bilateral processing of number agreement in noun phrases

The present experiment employed a grammatical priming task to explore the possible contributions of the left and right cerebral hemispheres to the processing of grammatical agreement. Stimuli were three-word noun phrases, with the prime centered above the fixation point and the target presented laterally to one visual field after a 600-ms stimulus onset asynchrony. Number agreement between primes and targets was varied such that the article of the prime could be consistent (i.e., each narrow shoe or all narrow shoes), inconsistent (i.e., all narrow shoe or each narrow shoes) or neutral (i.e., the narrow shoe(s)) with respect to the inflection of the target. Half of the subjects provided lexical decision responses and the other half pronunciation. The bilateral priming effect, obtained only in lexical decision, suggests that both the left and the right hemispheres are sensitive to certain grammatical cues. In addition to the task difference in priming, the inclusion of a neutral condition and of pseudo-inflected nonwords allowed these effects to be attributed to postlexical mechanisms.

Biochemical analysis of a 5S rRNA-associated sub-particle from trypsinized eukaryotic ribosomes

On limited trypsinization, eukaryotic ribosomes released sub-particles that comprised a 5S rRNA molecule and two peptides (a 32 kDa and a 14 kDa). By tryptic finger-printing and amino-terminal sequence analysis, these two peptides were determined to be derived from large subunit ribosomal protein L5 (rpL5). The 32 kDa peptide represents the rpL5 protein minus the amino terminal eight residues and the carboxyl terminal ends (approximately 21 residues), whereas the 14 kDa peptide comprised near the amino-terminal region. The time course of ribosome trypsinization revealed that the two peptides were released kinetically. The indicated that the amino and carboxyl terminal ends of rpL5 were the first to be hydrolyzed, suggesting that the two ends of the rpL5 protein were exposed on the surface of ribosomes. Exposure of the carboxyl-terminal end was confirmed by use of an anti-L5c antibody raised against the carboxyl terminal region of rpL5. The kinetic data also revealed that the nearby amino terminal region of rpL5 (represented by the 14 kDa peptide) was the last part of rpL5 to be hydrolyzed, which was considered to be the 5S rRNA binding site.

Interaction between triiodothyronine and ovarian steroid hormones on the regulation of the release of thyrotropin and thyrotropin-releasing hormone in vitro

In vivo and in vitro experiments were designed to examine [1] the effect of triiodothyronine (T3) and/or ovarian steroids on the spontaneous and thyrotropin-releasing hormone (TRH)-stimulated release of thyrotropin (TSH) by the anterior pituitary gland (AP) in vitro; and [2] the in vivo effects of T3 and ovarian steroids on TRH-release in vitro. In the experiment 1, ovariectomized-thyroidectomized (Ovx-Tx) rats were injected with triiodothyronine (T3, 2 micrograms/kg), estradiol benzoate (EB, 25 micrograms/kg), progesterone (P, 10 mg/kg), T3 plus EB, T3 plus P, EB plus P, or T3 plus EB and P for 6 days before decapitation. The AP was incubated with Locke's medium, challenged with TRH (30 nM), recovered and then with T3 (10 nM) only or with T3+TRH, 30 min for each interval. Mediobasal hypothalami (MBHs) were challenged with high potassium (60 mM) for 30 min. In the experiment 2, the APs of Ovx-Tx rats were enzymatically dispersed and the AP cells were pretreated with or without EB (0-6 nM) for 72 h, and further with T3 (10 nM) for 24 h, followed by an incubation for 30 min with TRH (0-100 nM). The spontaneous and TRH-induced release of TSH in vitro from rat APs, and pituitary TSH content were increased by T3, or T3 plus P as compared with the animals injected with vehicle, or P alone. EB inhibits the effect of T3 on TSH release in vitro. Application of T3 in vitro prevented the release of TSH in response to TRH. EB dose-dependently relieved the inhibitory effect of T3 on TRH-induced TSH release in vitro. TRH release from MBH was increased by EB and inhibited by T3 or P. EB prevented the inhibitory effect of T3 on TRH release. P plus T3 potentiated the stimulatory effects of EB on TRH release. These results suggest that [1] the reduction of the concentration of plasma TSH by T3 is at least in part due to the inhibitory effects of T3 on TRH release from mediobasal hypothalamus, and TSH release in response to TRH, [2] the increased content and release of TSH from rat AP tissue by T3 via an in vivo effect may be involved in a short feedback loop of TSH on TRH release, and [3] ovarian steroid hormones play an inhibitory role in regulating T3 effects on the release of TSH and TRH.

Gastric inhibitory polypeptide and gastric acid secretion in pregnant rats

The effects of pregnancy on the basal and pentagastrin-stimulated gastric acid secretion and the level of plasma gastric inhibitory polypeptide (GIP) in rats were studied on pentobarbital-anaesthetized non-pregnant rats and rats in the 1st, 2nd, or 3rd week of gestation. Acid output was determined by titration of the gastric perfusate. Basal secretion was collected for 45 min before a 30 min infusion of pentagastrin (8 micrograms/ml/300 g body weight). Concentration of plasma GIP was measured by a radioimmunoassay (RIA). The immunoreactivity of GIP-like substance in the extract of the rat placenta collected from the rat at day 21 of gestation was examined by RIA. The biological activity of GIP-like substance in the rat placenta extract was tested by the reduction of pentagastrin-stimulated gastric acid secretion in male rats. The basal level of gastric secretion was higher in late pregnancy as compared with the non-pregnant rats. Pentagastrin induced a greater increase of gastric acid secretion in early but not late pregnant rats as compared with the non-pregnant animals. The basal and post-pentagastrin level of plasma GIP was higher in rats in late pregnancy. Both immunoreactivity and biological activity of GIP exist in the rat placenta extract. These results suggest that the normalization of gastric acid secretion in late pregnant rats is at least in part due to the production of GIP-like substance from placenta.