[Progress and prospects of liquid-liquid phase separation in developmental diseases]

Membrane-bound organelles as well as membrane-free compartments exist in eukaryotic cells, which divide the nucleus and cytoplasm into distinct subregions and allow specific biochemical reactions to occur. The physiological mechanisms of membrane-bound organelles have been extensively characterized, but the formation and function of membrane-free compartments have not been thoroughly studied. Over the past decade, significant progress had been made in the studies about the role of liquid-liquid phase separation (LLPS) in the formation of membrane-free organelles. LLPS which serves as an aggregated separation mechanism for cellular biochemical reactions, is associated with a variety of physiological processes such as signal transduction and gene transcriptional regulation; while aberrant LLPS may contribute to the occurrence of developmental diseases. The present review investigates the role of LLPS as a mechanism of aggregation and segregation of cellular biochemical responses. The mechanisms of LLPS development and recent advances in the relationships between aberrant LLPS and developmental diseases are forward discussed, as well as how these advances may aid in the development of LLPS-based therapies.

[Investigation of familial tendency of endometriosis]

Objective: To investigate the familial heritability of endometriosis and to compare the clinical characteristics of patients with or without a family history of endometriosis. Methods: From January 2020 to June 2022, 850 patients with endometriosis confirmed by laparotomy or laparoscopy in Peking University Third Hospital were included in this study. Clinical data were collected, family history was followed up, and the differences of clinical indicators between patients with and without family history of endometriosis were compared. Results: A total of 850 patients were enrolled, with an average age of (33.8±7.0) years old, 315 (37.1%, 315/850) patients in stage Ⅲ and 496 (58.4%, 496/850) patients in stage Ⅳ. There were 100 patients with family history of endometriosis, accounting for 11.8% (100/850). Most of the 113 relatives involved were mothers, daughters and sisters (76.1%, 86/113), 81.5% (22/27) of the second and third degree relatives were maternal relatives. The median ages of patients with and without family history of endometriosis were 30 and 33 years old respectively at the time of diagnosis. The unmarried rate of patients with family history was higher [42.0% (42/100) vs 26.3% (197/750)]. The percentage of dysmenorrhea patients with family history was higher [89.0% (89/100) vs 55.5% (416/750)]. The medians of dysmenorrhea score in patients with and without family history were 6 and 2, and the median durations of dysmenorrhea were 10 and 1 years. There were significant differences in age, marital status, percentage of dysmenorrhea, dysmenorrhea score and duration (all P<0.001). The median levels of serum cancer antigen (CA) 125 in patients with family history and patients without family history at the time of diagnosis were 57.5 and 46.9 kU/L respectively, with a statistically significant difference (P<0.05). However, there were no significant differences between the two groups in nationality, bady mass index, menarche age, menstrual cycle, menstrual period, menstrual volume, serum CA_19-9 level, cyst location and size, stage, history of adverse pregnancy and childbirth, infertility, adenomyosis and deep infiltrating endometriosis (all P>0.05). By comparing the specific conditions of dysmenorrhea patients with and without family history of endometriosis, there were no significant differences between the two groups in terms of the age of onset of dysmenorrhea, duration of dysmenorrhea, primary and secondary dysmenorrhea, and progressive aggravation of dysmenorrhea (all P>0.05). The difference in the degree of dysmenorrhea in dysmenorrhea patients with family history of endometriosis was significant (P<0.001). Conclusions: The incidence of endometriosis has a familial tendency, and most of the involved relatives are the first degree relatives. Compared with patients without family history of endometriosis, endometriosis patients with family history are diagnosed at an earlier age, with higher percentage of dysmenorrhea, had more severe dysmenorrhea and higher serum CA₁₂₅ level.

[Factors influencing bilirubin elevation and its correlation with UGT1A1 gene polymorphism in the early postoperative period of transjugular intrahepatic portosystemic shunt]

Objective: To investigate the factors influencing total bilirubin elevation and its correlation with UGT1A1 gene polymorphism in the early postoperative period of transjugular intrahepatic portosystemic shunt (TIPS). Methods: 104 cases with portal hypertension and esophageal variceal hemorrhage (EVB) treated with elective TIPS treatment were selected as the study subjects and were divided into a bilirubin-elevated group and a normal bilirubin group according to the total bilirubin elevation level during the early postoperative period. Univariate analysis and logistic regression were used to analyze the factors influencing total bilirubin elevation in the early postoperative period. PCR amplification and first-generation sequencing technology were used to detect the polymorphic loci of the UGT1A1 gene promoter TATA box, enhancer c.-3279 T > G, c.211G > A, and c.686C > A. Logistic regression was used to analyze the correlation of four locus alleles and genotypes with elevated total bilirubin in the early postoperative period. Results: Among the 104 cases, 47 patients were in the bilirubin elevated group, including 35 males (74.5%) and 12 females (25.5%), aged (50.72 ± 12.56) years. There were 57 cases in the normal bilirubin group, including 42 males (73.7%) and 15 females (26.3%), aged (51.63 ± 11.10) years. There was no statistically significant difference in age (t = -0.391, P = 0.697) and gender (χ(2) = 0.008, P = 0.928) between the two groups of patients. Univariate analysis revealed that preoperative alanine transaminase (ALT) level (χ(2) = 5.954, P = 0.015), total bilirubin level (χ(2) = 16.638, P < 0.001), MELD score (χ(2) = 10.054, P = 0.018), Child-Pugh score (χ(2) = 6.844, P = 0.022), and postoperative portal vein branch development (χ(2) = 6.738, P = 0.034) were statistically significantly different between the two groups. Logistic regression analysis showed that preoperative ALT level, total bilirubin level, and portal vein branch development after TIPS were correlated with the elevated total bilirubin in the early postoperative period. The polymorphism of the c.211G > A locus of the UGT1A1 gene correlation had elevated total bilirubin in the early postoperative period of TIPS. The risk of elevated total bilirubin was increased in the population carrying allele A (P = 0.001, OR = 4.049) in the early postoperative period. Allelic polymorphisms in the TATA box promoter region and enhancer c.-3279 T > G and c.686C > A had no statistically significant difference between the bilirubin-elevated group and the normal bilirubin group. Conclusion: The preoperative ALT level, total bilirubin level, and portal vein branch development are correlated with the elevated total bilirubin in early postoperative patients. The polymorphisms of the UGT1A1 gene and enhancer c.211G > A are correlated with the occurrence of elevated total bilirubin in the early postoperative period of TIPS. Allele A carrier may have a higher risk of elevated total bilirubin in the early postoperative period.

Nicosulfuron stress on the glyoxalase system and endogenous hormone content in sweet maize seedlings

To reduce the harmful effects of nicosulfuron on sweet corn, the physiological regulation mechanism of sweet corn detoxification was studied. This study analyzed the effects of nicosulfuron stress on the glyoxalase system, hormone content, and key gene expression of nicosulfuron-tolerant "HK301" and nicosulfuron-sensitive "HK320" sweet corn seedling sister lines. After spraying nicosulfuron, the methylglyoxal (MG) content in HK301 increased first and then decreased. Glyoxalase I (GlyI) and glyoxalase II (GlyII) activities, non-enzymatic glutathione (GSH), and the glutathione redox state glutathione/(glutathione + glutathione disulfide) (GSH/(GSH + GSSG)) showed a similar trend as the MG content. Abscisic acid (ABA), gibberellin (GA), and zeatin nucleoside (ZR) also increased first and then decreased, whereas the auxin (IAA) increased continuously. In HK301, all indices after spraying nicosulfuron were significantly greater than those of the control. In HK320, MG accumulation continued to increase after nicosulfuron spraying and GlyI and GlyII activities, and GSH first increased and then decreased after 1 day of stress. The indicators above were significantly greater than the control. The GSH/(GSH + GSSG) ratio showed a decreasing trend and was significantly smaller than the control. Furthermore, ABA and IAA continued to increase, and the GA and ZR first increased and then decreased. Compared with HK320, HK301 significantly upregulated the transcription levels of GlyI and GlyII genes in roots, stems, and leaves. Comprehensive analysis showed that sweet maize seedlings improved their herbicide resistance by changing the glyoxalase system and regulating endogenous hormones. The results provide a theoretical basis for further understanding the response mechanism of the glyoxalase system and the regulation characteristics of endogenous hormones in maize under nicosulfuron stress.

Responses of photosynthesis, antioxidant enzymes, and related gene expression to nicosulfuron stress in sweet maize (Zea mays L.)

Weed control in maize (Zea mays L.) crops is usually undertaken using the postemergence herbicide nicosulfuron. The toxicity of nicosulfuron on maize, especially sweet maize, has been widely reported. In order to examine the effect of nicosulfuron on seedling photosynthetic characteristics, chlorophyll fluorescence, reactive oxygen species production, antioxidant enzyme activities, and gene expressions on sweet maize, nicosulfuron-tolerant "HK310" and nicosulfuron-sensitive "HK320" were studied. All experiment samples were subjected to a water or 80 mg kg^-1 of nicosulfuron treatment when sweet maize seedlings grow to the stage of four leaves. After treatment with nicosulfuron, results for HK301 were significantly higher than those for HK320 for net photosynthetic rate, transpiration rate, stomatal conductance, leaf maximum photochemical efficiency of PSII, photochemical quenching of chlorophyll fluorescence, and the electron transport rate. These results were contrary to nonphotochemical quenching and intercellular CO₂ concentration. As exposure time increased, associated effects also increased. Both O₂^·- and H₂O₂ detoxification is modulated by antioxidant enzymes. Compared to HK301, SOD, POD, and CAT activities of HK320 were significantly reduced as exposure time increase. Compared to HK320, the gene expression for the majority of SOD genes, except for SOD2, increased due to inducement by nicosulfuron, and it significantly upregulated the gene expression of CAT in HK301. Results from this study indicate that plants can improve photosynthesis, scavenging capabilities of ROS, and protective mechanisms to alleviate phytotoxic effect of nicosulfuron. Future research is needed to further elucidate the important role antioxidant systems and gene regulation play in herbicide detoxification in sweet maize.

MG-BERT: leveraging unsupervised atomic representation learning for molecular property prediction

MOTIVATION

Accurate and efficient prediction of molecular properties is one of the fundamental issues in drug design and discovery pipelines. Traditional feature engineering-based approaches require extensive expertise in the feature design and selection process. With the development of artificial intelligence (AI) technologies, data-driven methods exhibit unparalleled advantages over the feature engineering-based methods in various domains. Nevertheless, when applied to molecular property prediction, AI models usually suffer from the scarcity of labeled data and show poor generalization ability.

RESULTS

In this study, we proposed molecular graph BERT (MG-BERT), which integrates the local message passing mechanism of graph neural networks (GNNs) into the powerful BERT model to facilitate learning from molecular graphs. Furthermore, an effective self-supervised learning strategy named masked atoms prediction was proposed to pretrain the MG-BERT model on a large amount of unlabeled data to mine context information in molecules. We found the MG-BERT model can generate context-sensitive atomic representations after pretraining and transfer the learned knowledge to the prediction of a variety of molecular properties. The experimental results show that the pretrained MG-BERT model with a little extra fine-tuning can consistently outperform the state-of-the-art methods on all 11 ADMET datasets. Moreover, the MG-BERT model leverages attention mechanisms to focus on atomic features essential to the target property, providing excellent interpretability for the trained model. The MG-BERT model does not require any hand-crafted feature as input and is more reliable due to its excellent interpretability, providing a novel framework to develop state-of-the-art models for a wide range of drug discovery tasks.

Attenuation of a virulent swine acute diarrhea syndrome coronavirus strain via cell culture passage

Swine acute diarrhea syndrome coronavirus (SADS-CoV) is a newly identified enteric alphacoronavirus that causes fatal diarrhea in newborn piglets in China. Here, we propagated a virulent strain SADS-CoV/CN/GDWT/2017 in Vero cells for up to 83 passages. Four strains of SADS-CoV/GDWT-P7, -P18, -P48 and -P83 were isolated and characterized. Sequence alignments showed that these four novel strains exhibited 16 nucleotide mutations and resultant 10 amino acid substitutions in open reading frame 1a/1b, spike, NS3a, envelope, membrane and nucleocapsid proteins. Furthermore, a 58-bp deletion in NS7a/7b was found in P48 and P83 strains, which led to the loss of NS7b and 38 amino acid changes of NS7a. Pig infection studies showed that the P7 strain caused typical watery diarrhea, while the P83 strain induced none-to-mild, delayed and transient diarrhea. This is the first report on cell adaption of a virulent SADS-CoV strain, which gives information on the potential virulence determinants of SADS-CoV.

A rare case of thoracic spinal intradural extramedullary enterogenous cyst with acute onset: case report and literature review

The intraspinal enterogenous cyst, also called an neurenteric cyst, is a rare congenital disease. It was reported to be local to the C1 to L2 spinal segments, with the majority located in the cervicothoracic region. Most patients present with symptoms of progressive focal pain, myelopathic signs or radicular symptoms. We report a rare case of thoracic spinal intradural extramedullary enterogenous cyst with rapidly progressive weakness of both lower extremities. Additionally, we analysed the literature concerning the clinical features, diagnosis and prognosis of this disease.

[Soft-tissue angiosarcoma with pulmonary metastases: case report and literature review]

Objective: To investigate the differential diagnosis between pulmonary metastases from soft-tissue angiosarcoma and primary pulmonary angiosarcoma. Methods: A case of soft-tissue angiosarcoma with pulmonary metastases was reported and related literatures were reviewed. Results: A 39 year-old man complaining of hemoptysis, cough, and sputum for 10 months was admitted to our hospital in September 2013. He was initially diagnosed as having primary pulmonary angiosarcoma after wedge-resection biopsy of the lung. After 22 months since onset, he felt discomfort in his leg, which led to the confirmative diagnosis of soft-tissue angiosarcoma of the leg with multiple pulmonary metastases by a full-body PET/CT scan and core needle biopsy of the leg. Twenty-three articles concerning primary pulmonary angiosarcoma with complete records of history, treatment and follow-up of patients were included in the literature review. A total of 26 patients were reported in these articles, including 18 males, 8 females, age 19-85 years, average (52±18) years. Primary pulmonary angiosarcoma was mainly manifested as single or multiple pulmonary nodules or masses, with or without ground glass opacity. In our case, chest CT showed multiple thin-wall cysts and ground glass opacities, and recurrent spontaneous pneumothorax, which had never been reported in literatures on primary pulmonary angiosarcoma. Conclusions: Pulmonary metastases from soft-tissue angiosarcoma differed from primary pulmonary lesions in terms of chest imaging, with the former usually showing thin-wall cysts and pneumothorax. A full-body PET-CT was essential for differential diagnosis between primary and metastatic pulmonary angiosarcoma.

Circulating B7-H4 in serum predicts prognosis in patients with hepatocellular carcinoma

B7-H4 is member of the B7 family that negatively regulates the immune response, which are important for fine-tuning of the tumor microenvironment. Dysregulation of B7-H4 expression has been associated with tumor progression. However, expression level of B7-H4 in hepatocellular carcinoma (HCC) tissues is still a controversial topic. In addition, whether serum B7-H4 expression of HCC patients has any clinical value is unknown. We compared serum levels of B7-H4 in patients with HCC and healthy controls by using the ELISA method. Association between serum B7-H4 expression level and clinical parameters of HCC was further investigated. Log-rank test and Kaplan-Meier method were employed to evaluate the overall survival rate of HCC patients. Univariate and multivariate analysis of prognostic factors were performed with the Cox regression model. Our results showed that HCC patients had significantly higher serum B7-H4 level as compared with healthy controls (P < 0.001). In addition, serum B7-H4 expression was correlated with HCC clinical parameters including serum AFP expression and TNM stage. HCC patients in the higher serum B7-H4 expression group had a poorer 5-year overall survival rate (P = 0.028). Moreover, serum B7-H4 expression was shown to be an independent prognostic factor for HCC (P = 0.034). The findings from this study suggest that serum B7-H4 is an independent prognostic indicator for HCC and may be a promising biomarker for early diagnosis as well as disease prognosis of HCC.

Apoptosis induced by yessotoxins in Hela human cervical cancer cells in vitro

To investigate the apoptotic effects of an extract of red-tide algae, Protoceratium reticulatum, on HeLa cells, we used liquid chromatography-tandem mass spectrometry, optical microscopy, Hoechst 33342/propidine iodide staining, and DNA gel electrophoresis to analyze its constituents and toxicity, as well as rhodamine 123 staining to investigate changes in mitochondrial membrane potential. Analysis showed that the P. reticulatum extract contained the yessotoxins (YTXs) homo-YTX, 45-OH-YTX and 45-OH-homo-YTX. The results indicated that P. reticulatum extract negatively influences HeLa cells and induces their apoptosis.

Immuno-PCR for one step detection of H5N1 avian influenza virus and Newcastle disease virus using magnetic gold particles as carriers

Detecting avian influenza virus (AIV) and Newcastle disease virus (NDV) at low concentrations from tracheal and cloacal swabs of avian influenza- and Newcastle disease-infected poultry was carried out using a highly sensitive immunological-polymerase chain reaction (immuno-PCR) method. Magnetic gold particles were pre-coated with a capture antibody, either a monoclonal anti-AIV/H5 or monoclonal anti-NDV/F and viruses serially diluted ten-fold from 10(2) to 10(-5)EID(50)/ml. A biotinylated detection antibody bound to the viral antigen was then linked via a streptavidin bridge to biotinylated reporter DNA. After extensive washing, reporter DNA was released by denaturation, transferred to PCR tubes, amplified, electrophoresed and visualized. An optimized immuno-PCR method was able to detect as little as 10(-4)EID(50)/ml AIV and NDV. To further evaluate the specificity and the clinical application of this IPCR assay for AIV H5N1 and NDV, the tracheal swab specimens, taken from chickens which were infected with H5N1/AIV, H9N2/AIV, H7N2/AIV, NDV, IBDV, IBV/H(120), were detected by IPCR. Our data demonstrated that this monoclonal antibody-based immuno-PCR method provides a platform capable of rapid screening of clinical samples for trace levels of AIV H5 and NDV in one step.

Supratentorial Brain AVM Embolization with Onyx-18 and Post-Embolization Management. A Single-Center Experience

SUMMARY

Onyx is increasingly used in endovascular therapy of intracranial arteriovenous malformations (AVMs). However, the embolic effect and post-embolization management are still under discussion. We report our experience in the treatment of supratentorial brain arteriovenous malformations (SBAVMs) with Onyx and discuss post-embolic management. From June 2006 to July 2008, 20 patients with SBAVM were embolized with Onyx. There were 14 men and six women ranging from 14 to 64 years of age (mean 38.3 years). Initial symptoms included spontaneous hemorrhage (n=12), headaches (n=4), seizure (n=3) and incidentally disclosed after head trauma (n=1). After the endovascular procedure, all had subsequent treatment (follow-up angiogram, stereotactic radiosurgery or microsurgery) according to the obliteration degree. At angiography, seven patients (35%, 7/20) were completely obliterated (over 95% closure) after embolization while one suffered a small subarachnoid hemorrhage without permanent clinical sequelae. Four patients (20%, 4/20) were subtotally obliterated (over 80% closure), one patient who suffered severe cerebral edema after embolization underwent decompressive craniectomy, two patients had additional radiosurgery and one patient had follow-up angiogram. Nine patients (45%, 9/20) were partially obliterated (20-80% closure), five patients had additional surgery, two patients had additional radiosurgery and two patients had follow-up angiogram (one patient had intraventricular hemorrhage three months after embolization). Of all 20 AVMs, an average of 2.2 ml Onyx was used per patient and average volume reduction was 80% (range, 30%-99%). Onyx is suitable for embolization of SBAVMs because of its diffuse controllable properties. We suggest clinical follow-up after complete obliteration, additional radiosurgery or angiographic follow-up after subtotal obliteration and additional surgery after partially obliteration. More cases with long-term follow-up are needed to evaluate the long-term prognosis of our post-embolization management.

[Aneurysmal model induced by elastase]

OBJECTIVE

To induce the aneurysms by corrosion of aneurysmal wall with elastase, imitating clinical intracranial aneurysms patho-morhologically.

METHODS

The elastase-corroded arterial segments were transplanted onto lateral walls of carotid arteries. Follow-up and pathological examination of the aneurysms were made at two weeks and one month after construction.

RESULTS

The aneurysms formed by the transplantation of elastase-corroded arterial segments were found persistent or enlarge a little within one month. The aneurysms were purplish red and easy to rupture when exposed. The walls were deprived of elastic layer, and constructed by thin connective tissue.

CONCLUSIONS

The aneurysms made by transplanting elastase-corroded arterial segments are simple to built, while morphological and pathological characteristics are demonstrated good clinical mimicry, we believe our aneurysm model may well substitute the most popularly used aneurysms made of venous pouches.

Chronic smoking enhances tachykinin synthesis and airway responsiveness in guinea pigs

This study tests the hypothesis that the bronchial hyperreactivity induced by chronic cigarette smoke (CS) exposure involves the increased expression and release of tachykinins and calcitonin gene-related peptide (CGRP) from afferent nerve fibers innervating the airways. In guinea pigs chronically exposed to CS (20 min twice daily for 14-17 d), peak response in total lung resistance to capsaicin (1.68 microg/kg, intravenously) was significantly greater than that evoked by the same dose of capsaicin in control (air-exposed) animals. This augmented response in CS-exposed animals was abolished after treatment with CP-99994 and SR-48968, the neurokinin (NK)-1 and NK-2 receptor antagonists, suggesting the involvement of tachykinins in chronic CS-induced airway hyperresponsiveness (AHR). Further, substance P (SP)-like immunoreactivity (LI) and CGRP-LI in the airway tissue were significantly greater in the CS animals than in the control animals. Finally, beta-preprotachykinin (PPT, a splice variant from the PPT A gene encoding tachykinins including SP and NKA) messenger RNA levels as measured by in situ hybridization histochemistry displayed a significant increase in jugular ganglion neurons but not in dorsal root or nodose ganglion neurons. These data suggest that chronic CS-induced AHR is related to an increase in SP synthesis and release in jugular ganglion neurons innervating the lungs and airways.

Role of intrinsic airway neurons in ozone-induced airway hyperresponsiveness in ferret trachea

Exposure to ozone (O(3)) enhances airway responsiveness, which is mediated partly by the release of substance P (SP) from airway neurons. In this study, the role of intrinsic airway neurons in O(3)-induced airway responses was examined. Ferrets were exposed to 2 ppm O(3) or air for 1 h. Reactivity of isolated tracheal smooth muscle to cholinergic agonists was significantly increased after O(3) exposure, as were contractions to electrical field stimulation at 10 Hz. Pretreatment with CP-99994, a neurokinin type 1 receptor antagonist, partially abolished the O(3)-induced reactivity to cholinergic agonists and electrical field stimulation. The O(3)-enhanced airway responses were present in tracheal segments cultured for 24 h, a procedure shown to deplete sensory nerves while maintaining viability of intrinsic airway neurons, and all the enhanced smooth muscle responses were also diminished by CP-99994. Immunocytochemistry showed that the percentage of SP-containing neurons in longitudinal trunk and the percentage of neurons innervated by SP-positive nerve fibers in superficial muscular plexus were significantly increased at 1 h after exposure to O(3). These results suggest that enhanced SP levels in airway ganglia contribute to O(3)-induced airway hyperresponsiveness.

An external-sample liquid scintillation counting for 75Se and its application to selenoprotein detection

An external-sample liquid scintillation (LS) counting for the gamma emitter 75Se has been developed. An expressly designed well-type LS vial and a 2,5-diphenyoxazole-1,4-bis(5-phenyl-2-oxazoyl)-benzene-xylene solution containing 35% tertrabutylzinn allow 75Se to be counted in a standard LS counter with counting efficiency up to 43.2%, much higher than that of conventional LS counting method. This external sample LS has a good count rate linearity and exhibits low background count rates. After in vivo labeling with [75Se]selenite, 75Se distributions and the Se-containing proteins present in tissues of male rat were investigated by means of sodium dodecyl sulfate-polyacrylamide gel electrophoresis, external-sample LS and gamma-detector. Eight Se-containing proteins or protein subunits were detected to be Se-containing proteins or protein subunits in arterial wall, and their apparent molecular masses (Mr) were 76.4, 67.0, 57.4, 30.3, 25.4, 22.7, 21.7, and 15.1 kDa, respectively. In addition, eight 75Se-labeled proteins (Mr: 66.8, 57.0, 43.1, 30.0, 24.8, 19.8, 18.0, and 14.8 kDa) were found in brain homogenates, and nine 75Se-labeled proteins (Mr: 117.0, 78.0, 66.6, 57.2, 43.0, 38.1, 25.0, 20.1, and 18.0 kDa) were detected in testis homogenates. Some of them should be new biologically important selenoproteins that have not been identified so far.

Airway hyperresponsiveness to cigarette smoke in ovalbumin-sensitized guinea pigs

This study was carried out to determine if the bronchoconstrictive effect of cigarette smoke (CS) is enhanced when airway hyperresponsiveness is induced by ovalbumin (Ova) sensitization, and if so, whether an increase in endogenously released tachykinins is involved. The bronchoconstrictive effects of an acute CS inhalation challenge (15 ml; 50% concentration) were compared between guinea pigs sensitized with aerosolized Ova and matching control animals (receiving saline aerosol). In Ova-sensitized animals, there were marked increases in the numbers of eosinophils and neutrophils in the bronchoalveolar lavage fluid (BALF), which was accompanied by an elevated bronchomotor response to acetylcholine (ACh). The baseline lung resistance (RL) and dynamic pulmonary compliance (Cdyn) were not significantly different between the two groups; however, the same CS inhalation challenge evoked a significantly more intense bronchoconstriction in the Ova-sensitized group (control group: DeltaRL = 68 +/- 8%, DeltaCdyn = -26 +/- 6%; Ova group: DeltaRL = 425 +/- 76%; DeltaCdyn = -47 +/- 8%). The levels of substance P-like immunoreactivity (SP-LI) and calcitonin gene-related peptide-like immunoreactivity (CGRP-LI) measured in the bronchoalveolar lavage (BAL) collected after CS inhalation challenge were also significantly greater in Ova-sensitized animals than in control animals. Furthermore, pretreatment with SR-48968, a selective antagonist of neurokinin-2 (NK(2)) receptor, inhibited more than 85% of the enhanced bronchomotor responses to CS challenge, but did not significantly reduce the airway hyperresponsiveness to ACh in Ova-sensitized guinea pigs. These results show that Ova sensitization induces airway hyperresponsiveness to inhaled CS, and that the endogenous tachykinins evoked by CS-induced activation of lung C fibers play a primary role in this augmented response.

Airway hyperresponsiveness induced by chronic exposure to cigarette smoke in guinea pigs: role of tachykinins

This study was carried out to determine whether tachykinins released from lung C-fiber afferents play a part in the bronchial hyperreactivity induced in guinea pigs by chronic exposure to cigarette smoke (CS). Two matching groups of young guinea pigs were exposed to either mainstream CS (CS group) or air (control group) for 20 min twice daily for 14-17 days. There was no difference in the baseline total pulmonary resistance (RL) between the two groups, but the baseline dynamic lung compliance was reduced ( approximately 19%) in CS animals. The responses of RL to intravenous injections of ACh, neurokinin (NK) A, and capsaicin were all markedly increased in CS animals; for example, ACh at the same dose of 5.06 microg/kg increased RL by 207% in the control group and by 697% (n = 8; P < 0. 001) in the CS group. The increased responsiveness was accompanied by significant increases in the numbers of neutrophils, eosinophils, and macrophages in the bronchoalveolar lavage fluid in CS animals. Pretreatment with SR-48968 and CP-99994, antagonists of NK(1) and NK(2) receptors, respectively, did not alter the response of RL to ACh in control animals, but it abolished the elevated bronchoconstrictive response in the CS animals. Furthermore, the immunoreactivities of substance P and calcitonin gene-related peptide in the bronchoalveolar lavage fluid collected after capsaicin challenge were significantly increased in CS animals. These results show that chronic exposure to CS induced airway mucosal inflammation accompanied by bronchial hyperreactivity in guinea pigs and that the tachykininergic mechanism plays an important role in this augmented responsiveness.

Role of tachykinins in ozone-induced airway hyperresponsiveness to cigarette smoke in guinea pigs

Acute exposure to ozone (O3) induces airway hyperresponsiveness to various inhaled bronchoactive substances. Inhalation of cigarette smoke, a common inhaled irritant in humans, is known to evoke a transient bronchoconstrictive effect. To examine whether O3 increases airway responsiveness to cigarette smoke, effects of smoke inhalation challenge on total pulmonary resistance (RL) and dynamic lung compliance (Cdyn) were compared before and after exposure to O3 (1.5 ppm, 1 h) in anesthetized guinea pigs. Before O3 exposure, inhalation of two breaths of cigarette smoke (7 ml) at a low concentration (33%) induced a mild and reproducible bronchoconstriction that slowly developed and reached its peak (DeltaRL = 67 +/- 19%, DeltaCdyn = -29 +/- 6%) after a delay of >1 min. After exposure to O3 the same cigarette smoke inhalation challenge evoked an intense bronchoconstriction that occurred more rapidly, reaching its peak (DeltaRL = 620 +/- 224%, DeltaCdyn = -35 +/- 7%) within 20 s, and was sustained for >2 min. By contrast, sham exposure to room air did not alter the bronchomotor response to cigarette smoke challenge. Pretreatment with CP-99994 and SR-48968, the selective antagonists of neurokinin type 1 and 2 receptors, respectively, completely blocked the enhanced responses of RL and Cdyn to cigarette smoke challenge induced by O3. These results show that O3 exposure induces airway hyperresponsiveness to inhaled cigarette smoke and that the enhanced responses result primarily from the bronchoconstrictive effect of endogenous tachykinins.

The effects of temperature, light and water upon the hatching of the ova of Schistosoma japonicum

Eggs of Schistosoma japonicum were obtained from infected patients' feces from Yujiang City, China to observe the effects of temperature, light and water on the hatching of eggs. The temperature of water and light played important roles on the hatching of S. japonicum, but the type of water did not. A constant temperature of 28 degrees C and electrical light produced the highest rate of hatching, and reproducible results, whereas a temperature of 4 degrees C or 37 degrees C, and the absence of light inhabited the hatching of eggs. The percentage of eggs hatched during the first 8 hours of 24 hours incubation was 94.90%, so that using the hatching rate of the first 8 hours could approximate the total hatching rate of samples.

Combinations of three immunological assays for detecting anti-Toxoplasma IgG in the sera of patients infected with Toxoplasma gondii

Enzyme-linked immunosorbent assay (ELISA), Dot-ELISA and Dot-immunogold silver staining (Dot-IGSS) were simultaneously used to detect the specific IgG against Toxoplasma gondii in 65 patients infected with the protozoa. The positive rates were 86.51%, 92.51% and 98.64%, respectively. When ELISA and Dot-ELISA results were put together, the positive rate increased to 95.38%. When Dot-IGSS results were combined with those of ELISA or Dot-ELISA, the positive rate was raised to 100%. The difference in positive rate between ELISA and Dot-IGSS was significant (x2 = 6.93, p < 0.01), but no statistically significant differences were found between ELISA and Dot-ELISA or between Dot-ELISA and Dot-IGSS. Paired comparison of the reacting intensities of the sera in the 3 assays showed the correlations were highly significant (p < 0.001), with r = 0.608 between Dot-IGSS and Dot-ELISA, r = 0.8194 between Dot-IGSS and ELISA and r = 0.517 between Dot-ELISA and ELISA. Hence combination of different serological assays may increase their sensitivity and specificity for detecting the anti-Toxoplasma antibodies.

The non-randomness of the distribution of Trichuris trichiura and Ascaris lumbricoides eggs in faeces and the effect of stirring faecal specimens

Experiments were performed to describe the distribution of Trichuris trichiura and Ascaris lumbricoides eggs in faeces and to test for the effect of stirring faecal specimens prior to sampling. For each of 5 volunteers infected with A. lumbricoides and 7 volunteers infected with T. trichiura, helminth eggs were counted in 150 samples from a single stool specimen using the Kato-Katz smear technique. No significant differences between the distribution of eggs in samples from the surface and the centre of the specimens were found. Prior to stirring, eggs were found to be aggregately distributed in four of the specimens with T. trichiura and all of the specimens with A. lumbricoides. The distributions of eggs were not significantly altered by stirring the stool prior to sampling except in the case of one volunteer infected with A. lumbricoides for whom stirring reduced variability.

[Effects of inflammatory mediators on the release of CGRP from isolated mesenteric arterial bed of rat]

The purpose of the present study was to observe whether inflammatory mediators, such as: Prostaglandin E2 (PGE2), Bradykinin (BK), Histamine (HIS), Platelet active factor (PAF) and 5-hydroxytryptamine (5-HT), directly triggered the release of CGRP from perivascular nerves in isolated rat mesenteric arterial bed. The results showed that PGE2 (1-100 mumol/L) and BK (5-10 mumol/L) caused time- and concentration-dependent CGRP release, but HIS, PAF and 5-HT did not show significant effects. Our data indicate that PGE2 and BK are the major inflammatory mediators in triggering the release of CGRP from the perivascular CGRP-containing nerve.

[The roles of nitric oxide and prostaglandins in the endotoxin-induced release of calcitonin gene-related peptide (CGRP) in rat mesenteric artery]

The mechanism of endotoxin (ETX) -induced release of CGRP was studied in isolated mesenteric arterial bed. ETX (50 micrograms/ml) caused a 16-fold increase of the release of CGRP. The effect of ETX was enhanced by L-arginine (L-Arg), a substratum of nitric oxide synthase (NOS), by 41%, but inhibited by NG-nitro-L-arginine (L-NNA), an selective inhibitor of NOS, L-NNA, and methylium blue (MB), an inhibitor of guanylate cyclase, respectively by 35% and 36%. These observations suggested that the effect of ETX is, at least partially, mediated by elevation of intracellular cGMP induced by NO. When endothelial cells were removed, the above responses of L-NNA and L-Arg still existed, indicating that ETX activated neuronal, rather than endothelial, NOS. Indomethacin and ibupofen, inhibitors of cyclooxygenase, also inhibited ETX-induced CGRP release by 34% and 39% respectively. When L-NNA and indomethacin were both incubated, no additive effects were discernible. The data suggest that ETX triggers CGRP release partially through activation of NOS located in perivascular sensory nerve and increase of NO, which is followed by activation of cyclooxygenase.

[Endotoxin causes release of calcitonin gene-related peptide (CGRP) from the isolated mesenteric arterial bed in rat]

Our previous work has shown that CGRP is released into the circulation during endotoxin or hemorrhagic shock in animals and septic shock in patients. We have also identified the blood vessels as a major source of production of circulating CGRP in the endotoxic rat. In the present study we determined whether ETX could directly trigger release of CGRP from CGRP-containing perivascular nerves in isolated mesenteric arterial bed (MAB) of rat. The results showed that ETX caused time- and concentration (10-100 micrograms/ml) -dependent release of CGRP. ETX (50 micrograms/ml) is increased by 20 fold CGRP in perfusate 10-15 min after ETX. Characterization of CGRP in perfusates by reverse-phase HPLC showed one predominant peak which coeluted with synthetic rat CGRP. Pretreated MAB with capsaicin or ruthenium red inhibited ETX-induced release of CGRP by 90% and 65% respectively. ETX-induced CGRP release was decreased under Ca2+-free perfusion by 80%. The data suggest that ETX directly trigger the release of CGRP from capsaicin-sensitive sensory nerve innervating blood vessels. The release of CGRP is dependent on extra-cellular Ca2+ and Ca2+-induced Ca2+ release from the intracellular Ca2+ store which is sensitive to ruthenium red.

Dot-immunogold-silver staining in the diagnosis of cysticercosis

Dot-immunogold-silver staining (Dot-IGSS) and Dot-ELISA were used, with Taenia solium cyst fluid antigen, to detect specific antibodies in the sera of patients with cysticercosis. All 40 confirmed cases of cysticercosis were found to be positive when tested by 2 methods. The average titer of the sera detected by Dot-IGSS was 1:27,470, which was significantly higher than that detected by Dot-ELISA. The false positive rates were 2% and 4% in 50 healthy controls for Dot-IGSS and Dot-ELISA, respectively, with a low titer of 1:20.

[Effects of some physical and chemical factors on CGRP release from mesenteric arterial bed]

We have shown that calcitonin gene-related peptide (CGRP) is released into the circulation during endotoxin or hemorrhagic shock. In the present study, it was observed that low pH, elevated levels of lactic acid, hypertonic NaCl and hypertonic sucrose caused CGRP release from isolated mesenteric arterial bed (MAB) of rat. All the responses were blocked when MAB was pretreated with capsaicin. Ruthenium red, an inhibitor of Ca(2+)-induced Ca2+ release from intracellular Ca2+ pools, significantly inhibited the release of CGRP. In Ca2+ free medium, low pH, lactic acid and hypertonic solutions became no longer capable of inducing the release of CGRP. The above results suggest that the observed release of CGRP in MAB was mediated by capsaicin-sensitive sensory nerve endings, as a result of Ca(2+)-induced Ca2+ release from the intracellular Ca2+ store which is sensitive to ruthenium red.

Application of dot-immunogold-silver staining in the diagnosis of clonorchiasis

All 35 confirmed clonorchiasis cases showed a positive reaction in dot-immunogold-silver staining (Dot-IGSS) with a mean serum titre of 1:1656, while none of the sera from 35 normal individuals reacted. A seroepidemiological survey of middle-school students revealed a positive rate of 17.0% (142/836), and 76.1% (105/138) of the serologically positive students were egg positive in stool examination. The egg positive rates in those with antibody at levels of 1+ to 4+ were 57.1% (28/49), 75.7% (28/37), 94.7% (36/38) and 92.9% (13/14) respectively. It is believed that Dot-IGSS can be used for the clinical diagnosis and epidemiological survey of clonorchiasis.

The population biology and control of Necator americanus in a village community in south-eastern China

The population dynamic parameters of Necator americanus infections were estimated from longitudinal intensity and prevalence data from a village in south-eastern China. The theoretical predictions of a deterministic model incorporating these parameters were then compared with observed, horizontal, age-prevalence data from an infected population (N = 565), and an estimate of the basic reproduction rate (R0 = 3.7) of N. americanus was obtained. The findings indicate that populations of N. americanus might be easier to control by mass-treatment chemotherapy (eradication requiring only 63% of the population to be treated every year for 4 years) than those of Ascaris lumbricoides and Trichuris trichiura.

Comparative study of Dot-immunogold silver staining and Dot-ELISA for the detection of serum antibodies against Wuchereria bancrofti

Dot-immunogold silver staining (Dot-IGSS) and Dot-ELISA, using the soluble antigen of Brugia malayi, were employed to detect anti-Wuchereria bancrofti antibodies in 50 cases of Wuchereria bancrofti microfilaremia. The positive rates were 100% and 90% in Dot-IGSS and Dot-ELISA respectively. The average titer in the 45 positive cases was 1:184 (1:10-1:2560) for Dot-IGSS and 1:150 (1:10-1:2560) for Dot-ELISA, with 30 cases showing the same titer in both tests, 13 cases showing higher titer in Dot-IGSS than in Dot-ELISA and 2 cases in the former showing lower titers than in the latter. There was a linear relationship between the titers of antibodies detected by Dot-IGSS and by Dot-ELISA (r = 0.8443). Dot-IGSS, similar to Dot-ELISA, is easy to carry out and the result is easy to read. It is seen that Dot-IGSS is highly sensitive and specific and is practicable for immunodiagnosis and surveillance of filariasis.

The use of dot-immunogold-silver staining (dot-IGSS), dot-ELISA and dot-IGSS to detect serum antibodies from clonorchiasis patients: a comparative study

We report the use of immunogold-silver staining (IGSS), dot-ELISA and dot-IGSS methods in the study of clonorchiasis in China. These methods were employed to detect the antibody in sera from 40 clonorchiasis patients. The positive rates were 100%, 90.0% and 95.0%, respectively. When the three methods were used to examine 40 normal sera, the negative rates were 100%, 97.5% and 97.5%, respectively. These results suggest that IGSS, dot-ELISA and dot-IGSS are highly specific and sensitive in detecting anti-Clonorchis antibody in patients.

[Intravascular embolization in treatment of craniocerebral vascular diseases]

From Aug. 1986 to June 1992, 193 cases of craniocerebral vascular diseases were treated with intravascular embolization. Among these there were 52 cases of carotid-cavernous fistula (CCF), 31 intracranial aneurysms, 83 arteriovenous malformations (AVM), and 27 dural AVMs. Intravascular embolization was first used in the treatment of CCF and dural AVM. For those of non-clippable aneurysms, detachable balloon catheter was adopted, but investigation of whole brain vessels and Matas' test should be made before embolization. As to brain AVM, embolization or combination of embolization and surgery is practical in some cases. Use of IBCA glue or silk suture in embolization is depends on the anatomical feature of AVM.

[Embolization treatment of carotid-cavernous fistula with balloon catheter]

Fifty-five cases of carotid-cavernous fistula (CCF) were treated with detachable balloon catheter from Oct. 1986 to Aug. 1992. Of these cases, 52 were embolized successfully with patented carotid arteries in 36. The clinical data, neurological complications and embolization methods were evaluated. We believe that intravascular embolization is the best method for treating CCF.

Treatment of traumatic carotid-cavernous fistula with detachable balloon

From November 1986 to February 1989, 18 patients with traumatic carotid-cavernous fistulas were treated by means of detachable balloon, which was made by ourselves. Successful embolization was achieved in 15 patients. Draining features of the fistulas and methods of embolization were introduced. The method was compared with other methods. Selection of treatments and problems in embolization are discussed.