[Practical application of the Paris system for reporting urinary cytology]

Objective: To validate the diagnostic performance of the Paris system for reporting urinary cytology (TPS). Methods: A total of 7 046 urine cytology samples from 3 402 patients collected in the Department of Pathology, Beijing Hospital, China from January 2020 to January 2022 were analyzed. 488 patients had a biopsy or resection specimen during the follow-up period of 6 months. The sensitivity, specificity, risk of malignancy (ROM) and risk of high-grade malignancy (ROHM) of the TPS were evaluated using histological diagnosis as the golden standard. Results: Among the 7 046 samples, high-grade urothelial carcinoma (HGUC) accounted for 5.7% (399/7 046), suspicious for high-grade urothelial carcinoma (SHGUC) for 3.2% (227/7 046), atypical urothelial cells (AUC) for 8.4% (593/7 046), and negative for high-grade urothelial carcinoma (NHGUC) for 72.9% (5 139/7 046) including low-grade urothelial neoplasm (LGUN) for 0.8% (59/7 046) and insufficient samples for 9.8% (688/7 046). 488 patients had a bladder biopsy or resection in the follow-up of six months, including 314 males and 174 females, aged 27 to 92 years (average, 66 years). The ROHM of TPS was 94.7% in HGUC, 83.3% in SHGUC, 41.3% in AUC and 18.8% in NHGUC. The sensitivity and specificity of urine cytology were 70.1% (169/241) and 97.0% (162/167), respectively. The negative predictive value of NHGUC was 69.2% (162/234). Conclusions: The study has shown that TPS classification has high sensitivity and specificity, high ROHM for HGUC and SHGUC, and high negative predictive value for NHGUC. The application of TPS reporting system can better interpret the clinical significance of cytology samples, improve the accuracy of urine cytopathology and ensure continuous diagnostic consistency.

[A case of acute inhalation dinitrogen tetroxide poisoning]

Dinitrogen tetroxide is often used as an oxidant in rocket propellant and has strong irritant and corrosive properties. This paper analyzes the clinical data of a patient with dinitrogen tetroxide poisoning admitted in the 63710 Army Hospital of Chinese People's Liberation Army, so as to further explore the poisoning mechanism, clinical characteristics and key points of acute inhaled dinitrogen tetroxide poisoning.

[The malignant phenotype of calcineurin B homologous protein 2 in gastric cancer and its clinical significance]

Objective: To study the expression and clinical significance of calcineurin B homologous protein 2 (CHP2) in gastric cancer (GC) and its effect on malignant phenotype of GC cells. Methods: The protein expression of CHP2 in 297 GC tissue and 198 normal gastric tissue samples were detected by immunohistochemistry. The relationship between the expression of CHP2 and clinicopathologic parameters of GC were analyzed. CHP2-overexpression plasmids and CHP2-interference plasmids were transfected into GC cell lines respectively. Wound healing assay and Transwell experiment was used to detect the invasion and migration ability of GC cells, and cell counting kit-8 (CCK-8) method was used to detect the proliferation ability of GC cells. Results: The positive expression rate of CHP2 in GC was 68.7% (204/297), which was higher in benign margin (34.1%) (31/91), chronic gastritis (59.1%) (13/22), intestinal metaplasia (34.2%) (13/38), low-grade intraepithelial neoplasia (40.0%) (12/30) and high-grade intraepithelial neoplasia (41.2%)(7/17). The positive expression of CHP2 was correlated with tumor, node and metastasis (TNM) stage, lymph node metastasis and distant metastasis (all P<0.05), but not with gender, age, Laurén classification, human epidermal growth factor receptor 2 (HER2) levels, depth of invasion, carcinoembryonic antigen (CEA) level and CEA 19-9 level (all P>0.05). The results of multivariate analysis showed that high expression of CHP2 and TNM stage were both independent parameters for predicting GC patient prognosis (both P<0.05). Interference of CHP2 expression in HGC-27 cells suppressed proliferation and migration significantly (P<0.05). However, over-expression CHP2 in AGS cells promoted proliferation, and migration significantly (P<0.05). Conclusion: CHP2 plays an important role in the development of GC, which is expected to be a molecular marker for patient prognosis and a potential target of targeted therapy for GC patients.

Retrospective analysis of clinical characteristics and prognostic factors of neuroendocrine carcinoma of the gynecologic tract: A preliminary report of ten years follow-up

e18001

Background: To investigate the clinical characteristics and prognostic factors of neuroendocrine carcinoma of the gynecologic tract (NECGT). Methods: Patients with NECGT diagnosed during 2010 to 2019 were enrolled in this retrospective study. Clinical parameters were calculated, including age, childbearing history, initial symptoms, blood indexs, International Federation of Gynaecology and Obstetrics (FIGO) stages, treatment modalities and survival data. The cut-off values of parameters were screened by receiver-operating characteristic (ROC) curves and their significance was assessed by multivariate logistic regression. Results: We indentified forty five NECGT patients available with the median follow-up time of 5.5 months (9.7±1.98 months). 42 cases (93.3%) originated from cervix uteri, 2 cases (4.4%) from vagina and 1 case (2.2%) from fallopian tube. Irregular vaginal bleeding was the most frequent symptom at the first visit accounting for 75.6%. FIGO stages I to IV distributions were 16 (35.6%), 15 (33.3%), 6 (13.3%), and 8 patients (17.8%). Squamous carcinoma (16.7%) and adenocarcinoma (11.9%) were the common mixed pathological types. 66.7% patients underwent radical surgery, almost all of which received 4-6 cycles adjuvant chemotherapy and half followed by radiation therapy. While data analysis showed that adjuvant radiotherapy could not bring additional survival benefits (p = 0.523). The median PFS of enrolled patients was 14 months (1-78months). Pelvic recurrence (66.7%) and lymphatic metastasis (52.6%) were the main failure patterns. In multivariate analysis, leukocyte count (HR = 0.068, 95%CI: 0.007-0.673, p = 0.021), neutrophil-to-leukocyte ratio (HR = 0.151, 95%CI: 0.024-0.95, p = 0.044), lactic dehydrogenase (LDH) (HR = 6.632, 95%CI: 1.31-33.569, p = 0.022) and carbohydrate antigen-ca 125 (CA-125) (HR = 7.173, 95%CI: 1.25-41.06, p = 0.027) were the independent prognostic factors of PFS. In addition, age at natural menopause (ANM) later than 51.5years (p = 0.009) and an optimal maximum diameter > 62.1mm (p = 0.002) were closely related with poor survival. Conclusions: NECGT is a rare malignant tumor of female genital system. Surgery combined with chemotherapy is the essential treatment, addition of adjuvant radiotherapy did not improve survival. More high-quality clinical trials are needed to provide powerful evidence.

Meiotic block with roscovitine improves competence of porcine oocytes by fine-tuning activities of different cyclin-dependent kinases

Successful use of oocytes from small follicles (SFs) is of great importance for animal embryo production and human in vitro fertilization with reduced hormone-related side effects. How in vitro meiotic arrest maintenance (MAM) increases the competence of oocytes is not clear. In this study, pig oocytes recovered from SF of 1-2 mm and medium-follicles (MF) of 3-6 mm in diameter from abattoir ovaries were treated by various MAM treatments to improve their competence. The results showed that 25 µM roscovitine or 1 mM db-cAMP efficiently blocked germinal vesicle breakdown in both SF and MF oocytes suggesting a similar cyclin-dependent kinase (CDK) 1 level between the two oocyte groups. MAM with 15- and 25-µM roscovitine alone or with 1-mM db-cAMP improved competence of SF and MF oocytes, respectively, with a promoted chromatin configuration transition from surrounded nucleoli (SN) to re-decondensation (RDC) pattern that supported substantial gene transcription. However, MAM with db-cAMP alone or with higher concentrations of roscovitine did not improve oocyte competence, could not support an SN-to-RDC transition, and/or evoked a premature chromatin condensation (PMC) that suppressed gene transcription. Both CDK2 and CDK5 contents were higher (p < .05) in MF than in SF oocytes. It is concluded that the competence of pig oocytes, particularly that of SF oocytes can be improved by MAM using a proper roscovitine concentration that promotes gene transcription by inhibiting CDK5 while letting CDK2 off to prevent PMC.

[Protective effects of berberine against exhaustion exercise induced myocardial injury in rats]

Objective: To investigate the effect and possible mechanism of berberine (Ber) on myocardial injury induced by exhaustion exercise (Ee). Methods: Forty healthy male SPF Sprague-Dawley rats were randomly divided into 5 groups using the random unit group design method: control group, Ee group and Ee plus Ber group (low: 50 mg·kg(-1)·d(-1), medium: 100 mg·kg(-1)·d(-1) and high dose: 150 mg·kg(-1)·d(-1), n=8 each). Ber (1.5 ml) or equal volume saline was given per gavage for 14 days. Rats assigned to Ee groups underwent Ee swimming once daily and rats in control group remain sedentary. After 14 days, echocardiographic measurements were performed and left ventricular ejection fraction (LVEF) and fractional shortening (LVFS), left ventricular diastolic diameter (LVIDd) and left ventricular systolic diameter (LVIDs) were obtained. The morphological structure of heart was detected by HE and Masson staining. Serum superoxide dismutase (SOD) and malondialdehyde (MDA) were measured by enzyme-linked immunosorbent assay. Cardiomyocytes apoptosis was detected by TUNEL method. The protein expression of myocardial hypertrophy marker protein B-type natriuretic peptide (BNP) and apoptotic marker protein (Bcl-2, Bax) in rat myocardial tissue was detected by Western blot. Results: (1) Both LVFS and LVEF were significantly lower, and LVIDs and LVIDd were significantly larger in Ee group than those in control group (all P<0.01). The LVFS and LVEF in medium dose of Ber and high-dose Ber groups were significantly higher, and the LVIDs and LVIDd were significantly smaller than those in Ee group (all P<0.01). (2) The results of HE staining showed that the myocardial cells in control group were closely arranged, regular, normal in morphology, clear in structure, and uniform in staining. The myocardial cells of rats in Ee group were disarranged, cell staining was uneven, and vacuoles appeared in the cytoplasm. The disorder of myocardial cell arrangement and unequal staining in the medium dose of Ber were attenuated than in Ee group. The Masson staining results showed that the myocardial cells in control group were closely arranged, regular, normal in shape, clear in structure, and rarely blue-stained (fibrosis). Myocardial cells in rats in Ee group showed obvious fibrosis. The myocardial cell fibrosis in rats with medium dose of Ber was significantly reduced than exercise group. (3) MDA content in myocardial tissue of rats in Ee group was significantly higher than that of control group, and MDA content in myocardial tissue of rats in medium dose of Ber group was significantly lower than in Ee group (P<0.01). The SOD activity of myocardial tissue in rats was significantly lower than that of control group, while that of rats with medium dose of Ber was significantly higher than that of rats in Ee group (P<0.01). (4) TUNEL staining results showed that only a small amount of apoptosis myocardial cells were seen in control group, and a large number of apoptosis myocardial cells were seen in rats in Ee group. However, the number of apoptotic cardiomyocytes in medium dose of Ber was significantly lower than that in Ee group. The AI of rat cardiomyocytes was significantly higher than that of control group (P<0.01), and the AI of rat cardiomyocytes in median dose of Ber group was significantly lower than in Ee group (P<0.01). (5) BNP and Bax protein expression in the myocardial tissues of rats in Ee group were significantly higher than in control group (P<0.01). BNP and Bax protein expression in the myocardial tissues in median dose of Ber group were significantly lower than that of Ee group (P<0.01). The myocardial protein expression level of Bax was significantly higher, and the myocardial protein level of Bcl-2 was significantly lower in Ee group than in control group (both P<0.01), treatment with median dose of Ber could partly reverse above changes (both P<0.01). Conclusion: Ber can attenuate exhaustion exercise induced myocardial injury and remodeling in rats, and the beneficial effects of Ber might possibly be mediated by reducing free radical release and cardiomyocytes apoptosis.

Intelligently Taking Out Universal Screws and Nail Caps After Spine Internal Fixation

The purpose of this study was to present a surgical technique for taking out universal screw and nail caps which were difficult to removed. We used a variety of industrial hex wrenches, dental drills, and other equipment to take out internal hex nuts with different specifications (32 pieces) and universal screws (15 pieces) in 28 patients. A total of 32 nuts were taken out, 3 of which were polished by the industrial drill. A total of 17 were spun by hand, 2 were spun by locking pliers, 10 were turned by “I” type screwdriver, and 3 were turned by bone blade. A total of 15 screws were taken out, 9 of which were removed with a wrench and the other 6 by means of locking pliers after re‐fixing with a truncated titanium rod. The novel technique is simple and provides a solution following failure of a supporting device.

Enamel matrix proteins regulate hypoxia-induced cellular biobehavior and osteogenic differentiation in human periodontal ligament cells

Hypoxia is a crucial microenvironment for inflamed periodontal tissue and periodontal wound healing. Enamel matrix proteins (EMPs) potentially can promote the formation of new periodontium. The effects of EMPs on periodontal ligament cells under hypoxia, however, remain unclear. We investigated the effects of EMPs on cellular biobehavior and osteogenic differentiation of human periodontal ligament cells (hPDLCs) under hypoxia. Under cobalt chloride (CoCl₂)-induced hypoxia, cellular biobehavior of hPDLCs, including proliferation, attachment, spreading, and migration with or without EMPs, was evaluated by 3-(4, 5-dimethylthiazol- 2-yl)-2, 5-diphenyl tetrazolium bromide (MTT), cell counting, spreading area measurement and wound scratch assay. The osteogenic activity of hPDLCs was assessed using alkaline phosphatase (ALP) and alizarin red S staining (ARS). The expressions of osteogenic genes including runt related transcription factor 2 (Runx2), ALP, osteocalcin (OCN) and collagen type I (Col-I) were detected using real time quantitative PCR, western blot and immunocytochemistry assays. The biobehavior and osteogenic differentiation of hPDLCs were inhibited significantly under hypoxia. EMPs have no effect on cell proliferation under mimicked hypoxia. EMPs partly reversed the inhibitory effects of hypoxia, however, for other cellular biobehavior including attachment, spreading and migration, and markedly up-regulated osteogenic differentiation activities including ALP, mineralization ability and the expressions of osteogenic genes such as Runx2, ALP, osteocalcin, and collagen type I in hPDLCs under hypoxia. EMPs attenuate the hypoxic injury to cellular biobehavior and osteogenic differentiation in hPDLCs under hypoxia.

[Mechanism of alpha-lipoic acid in treating TNBS-induced colitis in mice]

Objective: To investigate whether α-lipoic acid (ALA) regulates autophagy in the pathogenesis of colitis through the mammalian target of rapamycin (mTOR) signaling pathway. Methods: Balb/c mouse colitis model was induced with 2, 4, 6-trinitrobenzenesulfonic acid (TNBS). Male Balb/c mice (22-25 g) were divided into four groups: control group, ALA group, colitis group, and ALA treatment group, with 10 mice in each group. ALA was administered at a dose of 80 mg/kg once a day for 7 days. The colon weight index, the disease activity index (DAI) and the histologic degeneration score (HDS) of colon tissue in each group were calculated. The autophagy gene Beclin-1 mRNA level was detected by RT-PCR. The levels of mTOR, phosphorylated mTOR (p-mTOR), and Beclin-1 proteins were detected by Western blot. Results: Compared with the control group, there was no statistically significant difference in colon weight index in the ALA group[(9.21±0.57)vs(8.91±0.91)g/kg, P>0.05], but increased in the colitis group [(12.65±1.33)g/kg, P<0.05] and decreased in the ALA treatment group [(10.04±1.02)g/kg, P<0.05]; there were no significant differences in DAI or HDS in the ALA group, but significantly increased in the colitis group, and decreased in the ALA treatment group (all P<0.05). The Beclin-1 mRNA and protein levels showed no significant differences between the control and the ALA groups (1.00±0.12 vs 1.05±0.05, 1.00±0.11 vs 1.00±0.06). However, the expression of Beclin-1 was significantly decreased in the colitis group compared to the control group (0.51±0.07 vs 1.00±0.12, 0.52±0.07 vs 1.00±0.11, both P<0.05), but significantly increased in the ALA treatment group compared to the colitis group (1.75±0.09 vs 0.51±0.07, 1.82±0.14 vs 0.52±0.07, both P<0.05). The mTOR total protein levels were not significantly different among the four groups, but the p-mTOR level was significantly higher in the colitis group than in the control group (3.07±0.20 vs 1.00±0.07), and reduced in the ALA treatment group than in the colitis group (1.49±0.11 vs 3.07±0.20) (all P<0.05). Conclusion: ALA may improve the TNBS-induced colitis in mice by inhibiting the phosphorylation of mTOR to promote autophagy.

[Value of endobronchial ultrasound-guided transbronchial needle aspiration of enlarged mediastinal lymph nodes and analysis of false negative results]

Objective: To explore the diagnostic value of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) in the diagnosis of enlarged mediastinal lymph nodes, and to analyze the reasons of false negative results of EBUS-TBNA. Methods: A retrospective analysis of the clinical and imaging data of 389 patients who underwent EBUS-TBNA for sampling enlarged hilar and mediastinal lymph nodes from October 2009 to October 2015 in Shandong Tumor Hospital, to evaluate its significance in the diagnosis of enlarged mediastinal lymph nodes, and to analyze the reasons of false negative results. Results: Among the 389 collected cases, positive biopsy results were obtained in 362 cases, and false negative results in 27 cases. The sensitivity, specificity, positive predictive value and negative predictive value were 92.9%, 100%, 100% and 25.0%, respectively. There was a positive correlation between the size of lymph node and biopsy positive rate (P=0.021). The subcarinal lymph nodes had the highest positive rate (97.7%), followed by the paratracheal lymph nodes (91.2%), with a statistically significant difference (P=0.006). The positive rates obtained by cytology (88.7%) and pathology (92.5%, ) showed no significant difference (P=0.065). The positive rate of EBUS-TBNA was not correlated with pathological types (P=0.932). Needle types (21G, 22G) had no significant effect on diagnosis accuracy (P=0.142). Conclusions: EBUS-TBNA is a practical technology for diagnosis of enlarged mediastinal lymph nodes, with unique characteristics such as minimally invasiveness, local anesthesia, good safety and repeatability. Along with the accumulation of surgical experience, improvement of operative skills, more close cooperation between surgeons, cytologists and pathologists, false negative results will be reduced and positive rate of EBUS-TBNA examination will be further improved.

Aquaporin in the proliferation and apoptosis of diabetic myocardial cells

The aim of this study was to explore the effect of aquaporin on the molecular mechanism of human diabetic myocardial cell apoptosis. The methylthiazolyle tetrazolium assay was used to detect the inhibitory effect of different concentrations of aquaporin on cell growth. The rate of aquaporin-induced myocardial cell apoptosis was detected by flow cytometric analysis of Annexin V-fluorescein isothiocyanate/propidium iodide double-stained cells. We also attempted to quantify the expression of Bcl-2, Bax, caspase-3, and survivin in diabetic myocardial cells by western blot analysis. Aquaporin was found to inhibit the proliferation of diabetic myocardial cells in a concentration-dependent manner; the increase in aquaporin concentration led to an increase in Bax (apoptosis protein) expression, decrease in Bcl-2 expression (anti-apoptosis protein), increase in the Bax/Bcl-2 ratio, and a decrease in caspase-3 and survivin expression (P < 0.05). Therefore, aquaporin significantly inhibits the proliferation of diabetic myocardial cells and cell apoptosis in a dose-dependent manner by upregulating the ratio of Bax/Bcl-2 protein expression, activating the caspase-3 protein cascade, and regulating the expression of survivin.

Optimized Protocols for In Vitro Maturation of Rat Oocytes Dramatically Improve Their Developmental Competence to a Level Similar to That of Ovulated Oocytes

The developmental capacity of in vitro-matured (IVM) oocytes is markedly lower than that of their in vivo-matured (IVO) counterparts, suggesting the need for optimization of IVM protocols in different species. There are few studies on IVM of rat oocytes, and there are even fewer attempts to improve ooplasmic maturation compared to those reported in other species. Furthermore, rat oocytes are well known to undergo spontaneous activation (SA) after leaving the oviduct; however, whether IVM rat oocytes have lower SA rates than IVO oocytes and can potentially be used for nuclear transfer is unknown. In this study, we investigated the effects of maturation protocols on cytoplasmic maturation of IVM rat oocytes and observed the possibility to reduce SA by using IVM rat oocytes. Ooplasmic maturation was assessed using multiple markers, including pre- and postimplantation development, meiotic progression, CG redistribution, redox state, and the expression of developmental potential- and apoptosis-related genes. The results showed that the best protocol consisting of modified Tissue Culture Medium-199 (TCM-199) supplemented with cysteamine/cystine and the cumulus cell monolayer dramatically improved the developmental competence of rat oocytes and supported both pre- and postimplantation development and other ooplasmic maturation makers to levels similar to that observed in ovulated oocytes. Rates of SA were significantly lower in IVM oocytes than in IVO oocytes when observed at the same intervals after nuclear maturation. In conclusion, we have optimized protocols for IVM of rat oocytes that sustain ooplasmic maturation to a level similar to ovulated oocytes. The results suggest that IVM rat oocytes might be used to reduce SA for rat cloning.

A saxitoxin-binding aptamer with higher affinity and inhibitory activity optimized by rational site-directed mutagenesis and truncation

Saxitoxin (STX), a member of the family of paralytic shellfish poisoning toxins, poses toxicological and ecotoxicological risks. To develop an analytical recognition element for STX, a DNA aptamer (APT(STX1)) was previously discovered via an iterative process known as Systematic Evolution of Ligands by Exponential Enrichment (SELEX) by Handy et al. Our study focused on generating an improved aptamer based on APT(STX1) through rational site-directed mutation and truncation. In this study, we generated the aptamer, M-30f, with a 30-fold higher affinity for STX compared with APT(STX1). The Kd value for M-30f was 133 nM, which was calculated by Bio-Layer Interferometry. After optimization, we detected and compared the interaction of STX with aptamers (APT(STX1) or M-30f) through several techniques (ELISA, cell bioassay, and mouse bioassay). Both aptamers' STX-binding ability was demonstrated in all three methods. Moreover, M-30f performs better than its parent sequence with higher suppressive activity against STX. As a molecular recognition element, M-30f has good prospects for practical application.

Dynamics and correlation of serum cortisol and corticosterone under different physiological or stressful conditions in mice

Although plasma corticosterone is considered the main glucocorticoid involved in regulation of stress responses in rodents, the presence of plasma cortisol and whether its level can be used as an indicator for rodent activation of stress remain to be determined. In this study, effects of estrous cycle stage, circadian rhythm, and acute and chronic (repeated or unpredictable) stressors of various severities on dynamics and correlation of serum cortisol and corticosterone were examined in mice. A strong (r = 0.6–0.85) correlation between serum cortisol and corticosterone was observed throughout the estrous cycle, all day long, and during acute or repeated restraints, chronic unpredictable stress and acute forced swimming or heat stress. Both hormones increased to the highest level on day 1 of repeated-restraint or unpredictable stresses, but after that, whereas the concentration of cortisol did not change, that of corticosterone showed different dynamics. Thus, whereas corticosterone declined dramatically during repeated restraints, it remained at the high level during unpredictable stress. During forced swimming or heat stress, whereas cortisol increased to the highest level within 3 min., corticosterone did not reach maximum until 40 min. of stress. Analysis with HPLC and HPLC-MS further confirmed the presence of cortisol in mouse serum. Taken together, results (i) confirmed the presence of cortisol in mouse serum and (ii) suggested that mouse serum cortisol and corticosterone are closely correlated in dynamics under different physiological or stressful conditions, but, whereas corticosterone was a more adaptation-related biomarker than cortisol during chronic stress, cortisol was a quicker responder than corticosterone during severe acute stress.

Antioxidant supplementation overcomes the deleterious effects of maternal restraint stress-induced oxidative stress on mouse oocytes

In this study, using a mouse model, we tested the hypothesis that restraint stress would impair the developmental potential of oocytes by causing oxidative stress and that antioxidant supplementation could overcome the adverse effect of stress-induced oxidative stress. Female mice were subjected to restraint stress for 24 h starting 24 h after equine chorionic gonadotropin injection. At the end of stress exposure, mice were either killed to recover oocytes forin vitromaturation (IVM) or injected with human chorionic gonadotropin and caged with male mice to observein vivodevelopment. The effect of antioxidants was testedin vitroby adding them to IVM medium orin vivoby maternal injection immediately before restraint stress exposure. Assays carried out to determine total oxidant and antioxidant status, oxidative stress index, and reactive oxygen species (ROS) and glutathione levels indicated that restraint stress increased oxidative stress in mouse serum, ovaries, and oocytes. Whereas the percentage of blastocysts and number of cells per blastocyst decreased significantly in oocytes from restraint-stressed mice, addition of antioxidants to IVM medium significantly improved their blastocyst development. Supplementation of cystine and cysteamine to IVM medium reduced ROS levels and aneuploidy while increasing glutathione synthesis and improving pre- and postimplantation development of oocytes from restraint-stressed mice. Furthermore, injection of the antioxidant epigallocatechin gallate into restraint-stressed mice significantly improved the blastocyst formation and postimplantation development of their oocytes. In conclusion, restraint stress at the oocyte prematuration stage impaired the developmental potential of oocytes by increasing oxidative stress and addition of antioxidants to IVM medium or maternal antioxidant injection overcame the detrimental effect of stress-induced oxidative stress. The data reported herein are helpful when making attempts to increase the chances of a successful outcome in human IVF, because restraint was applied at a stage similar to the FSH stimulation period in a human IVF program.

Immunohistochemical localization of glucagon and pancreatic polypeptide on rat endocrine pancreas: coexistence in rat islet cells

We used immunofluorescence double staining method to investigate the cellular localization of glucagon and pancreatic polypeptide (PP) in rat pancreatic islets. The results showed that both A-cells (glucagon-secreting cells) and PP-cells (PP-secreting cells) were located in the periphery of the islets. However, A-cells and PP-cells had a different regional distribution. Most of A-cells were located in the splenic lobe but a few of them were in the duodenal lobe of the pancreas. In contrast, the majority of PP-cells were found in the duodenal lobe and a few of them were in the splenic lobe of the pancreas. Furthermore, we found that 67.74% A-cells had PP immunoreactivity, 70.92% PP-cells contained glucagon immunoreactivity with immunofluorescence double staining. Our data support the concept of a common precursor stem cell for pancreatic hormone-producing cells.

Immunohistochemical localization of glucagon and pancreatic polypeptide on rat endocrine pancreas: coexistence in rat islet cells

We used immunofluorescence double staining method to investigate the cellular localization of glucagon and pancreatic polypeptide (PP) in rat pancreatic islets. The results showed that both A-cells (glucagon-secreting cells) and PP-cells (PP-secreting cells) were located in the periphery of the islets. However, A-cells and PP-cells had a different regional distribution. Most of A-cells were located in the splenic lobe but a few of them were in the duodenal lobe of the pancreas. In contrast, the majority of PP-cells were found in the duodenal lobe and a few of them were in the splenic lobe of the pancreas. Furthermore, we found that 67.74% A-cells had PP immunoreactivity, 70.92% PP-cells contained glucagon immunoreactivity with immunofluorescence double staining. Our data support the concept of a common precursor stem cell for pancreatic hormone-producing cells.

Dual activities of human prolidase

The cDNA encoding human liver prolidase derived from a healthy adult's liver was cloned into the expression vector pPIC9K of Pichia pastoris to construct the recombination expression vector pPIC9K-P. The pPIC9K-P was digested by restriction enzyme Pme I, and then transformed into P. pastoris GS115 by electroporation. Transformants (the insertion recombinant) were induced by methanol to express the recombination protein. The optimal induction conditions (medium pH, methanol concentration and induction time) of the insertion transformant with the highest enzymatic activity were estimated by orthogonal experimental design L9(3(4)). The SDS-PAGE of the recombinant human prolidase (rh-prolidase) in induction medium showed a molecular weight of 73 kDa. The activities of the rh-prolidase and organophosphoric acid anhydrolases (OPAA) were assayed by colorimetric methods. The recombinant enzyme catalyzed the hydrolysis of organophosphorous compound soman as well as the hydrolysis of dipeptide Gly-Pro. Under the optimal induction conditions, the maximal activities of prolidase and OPAA came to 44.1 and 54.8 nmol/min/mg protein respectively in the medium supernatant. The rh-prolidase purified from the supernatant by ion exchange gradient chromatography (DEAE-Sepharose Fast Flow) and gel filtration chromatography (Sephacryl S-200 High Resolution) showed a single band by SDS-PAGE analysis. The purified rh-prolidase could decompose soman via hydrolytic reaction in vitro.

Synthetic antigenic decapeptides of human brain acetylcholinesterase cross-immunoreact with peptide-specific antibodies against Torpediniformes narcine timlei acetylcholinesterase

Antigenic decapeptides of human brain acetylcholinesterase (AChE) were investigated for immunoreactivity with the rabbit anti-Torpediniformes narcine timlei AChE polyclonal antibody (anti-narcine AChE polyclonal antibody). The decapeptides were synthesized using the multipin combinatorial chemical synthesis technique and biotinylated at N-terminals. Rabbit anti-narcine AChE polyclonal antibodies were purified by Protein A-Sepharose CL 4B column chromatography. Enzyme-linked immunosorbent assay (ELISA) was used for the assay of the reaction between the antigen and the antibody. Seven of 11 antigenic synthetic decapeptides of human brain AChE showed obvious immunoreactivity with the rabbit anti-narcine AChE polyclonal antibodies. The similarity of the AChE sequences of humans and Torpedo species were compared thereby with the epitopes indicated. The results indicate that the epitopes of human brain AChE and Torpedo AChEs have been highly conserved during evolution. In view of this, no N-glycosylation site was found in the antigenic decapeptides tested, they all belong to oligopeptide epitopes.

High-level expression of human butyrylcholinesterase gene in Bombyx mori and biochemical-pharmacological characteristic study of its product

The human butyrylcholinesterase (BChE, EC 3.1.1.8) gene was highly expressed in Bombyx mori using baculovirus vector, and the biochemical-pharmacological properties of its product were studied. BChE cDNA was cloned into transfer vector pBn96 and co-transfected with wild-type Bombyx mori nucleopolyhedrovirus (BmNPV) DNA into BmN cells. The recombinant virus with the highest enzyme activity was sorted out and purified. Once the BmN cells or silkworm larvae had been infected with the recombinant virus, recombinant human BChE (rhBChE) could be secreted into the culture medium or the hemolymph of the larvae at levels of 1.5 mg x L(-1) and 35 mg x L(-1), respectively. Western blot and enzymatic staining of the electrophoresis gel of non-denatured protein showed that rhBChE manifested similar antigenicity and enzyme activity to native human BChE (nhBChE). The production of rhBChE in the hemolymph was 23-fold higher than that in BmN cells and about 280-fold that in Chinese hamster overy cells (125 microg x L(-1)). This is the first report of human BChE expression in silkworm with the highest level of yield so far. rhBChE was highly similar to nhBChE in respect to substrate affinity, inhibitor sensitivity, and reactivity of the inhibited enzyme. It is suggested that rhBChE functions as well as nhBChE and has potential practical value.

Epitopes of human brain acetylcholinesterase

The main purpose of the present work was to identify B-cell epitopes on human brain acetylcholinesterase (AChE) by the synthetic peptide approach. Five hundred and seventy-four decapeptides comprising amino acids No. n to n+9 (where n denotes the residue number of the 583 amino acids in the primary structure of human brain AChE and is an integer in the range 1-574) were synthesized, using the multipin combinatorial chemical synthesis technique, and biotinylated. Epitopes of human brain AChE were detected by enzyme-linked immunosorbent assay (ELISA) and compared with the predicted epitopes of human AChE by 'Goldkey' software. Among 574 synthetic decapeptides, 47 decapeptides at 11 antigenic regions showed immunoreactivity with mouse anti-human brain AChE polyclonal antibodies. The minimum sequence of epitope was defined at every antigenic region explored. The locations and sequences of the former ten continuous epitopes at the 11 antigenic regions of the human brain AChE had been identified as follows: TPVLVWIY (112-119), RTVLVSMNY (143-151), LLDQRLALQW (173-182), RRATQLAH (246-253), VFRFSFVPV (294 approximately 302), KDEGSYFLVY (332-341), RVYA (424-427), LMRY (476-479), KAPQWPPY (496-503), GLRAQACAFW (523-532). The rate of hits of the predicted epitopes from the software came out at 33%. In our work, the epitopes of human AChE have been mapped by purified polyclonal antibody at eleven distinct sites in the primary structure.

Systematic study of the substituted active C-terminus of hirudin

Hirudin, a potent clinical thrombin inhibitor from Hirudo medicinalis, consists of 65 amino acids in a single chain. In this paper, we systematically synthesize a series of C-terminal (desulfo hirudin45-65) peptides substituted by 20 natural L-amino acids via the Multipin method. The resulting peptide library is subsequently screened using an alpha-thrombin-mediated fibrinogen clotting assay and alpha-thrombin-induced amidolytic hydrolysis assay.

Grafting of genetically modified human fetal fibroblasts to produce human butyrylcholinesterase in mice

Human diploid fibroblast cultures were established from fetal skin tissue. Enzymic dissociation yielded cultures of higher growth capacity of fibroblasts than those prepared by mechanical dissociation followed by spontaneous outgrowth of cells. Transfer of recombinant human butyrylcholinesterase (BChE, EC 3.1.1.8) gene into primary human fibroblasts was achieved successfully using lipofection and retrovirus-mediated transfection. The analysis of drug-resistant colonies suggested the presence of the transcripted BChE mRNA in the cytoplasm of transfected cells. The secreted BChE protein in culture medium was assayed for enzyme activity using butyrylthiocholine as substrate. The genetically modified fibroblasts were mixed with rat tail collagen and transplanted subcutaneously and intraperitoneally to mice. Immunoreactive human BChE appeared in the plasma from the transplanted mice. reaching the top level at day 13. It was not present any longer in most of the mice 20 days later.

Apoptosis and necrosis induced by sulfur mustard in Hela cells

AIM

To study the apoptotic effect of sulfur mustard (SM) on Hela cells.

METHODS

Exponentially growing Hela cells were treated with SM at various concentrations for 3 h, then apoptosis was examined by electron-microscope, DNA gel electrophoresis, and flow cytometry.

RESULTS

SM 1 mumol.L-1 arrested cell growth. After treatment with SM 10-100 mumol.L-1, cells were mainly blocked at G1-phase with apoptosis. Agarose gel electrophoresis of DNA from cells treated with SM revealed "DNA Ladder." About 33% of the Hela cells showed apoptosis 12 h after 3-h treatment with SM 100 mumol.L-1 as determined by flow cytometry and the S-phase cells were more susceptible. However, SM 1000 mumol.L-1 caused marked necrosis in Hela cells.

CONCLUSION

SM caused 2 distinct forms of cell death, apoptosis or necrosis, in Hela cells in a concentration-dependent manner.

Prophylactic effect of methylene blue against neurotoxicity of sodium nitroprusside

AIM

To examine the effect of methylene blue (MB) on cytotoxicities of sodium nitroprusside (SNP) and cyclic guanosine monophosphate (cGMP) in cultivated cerebellar neurons.

METHODS

The cytotoxicities of xenobiotic SNP and cGMP on cultivated murine cerebellar neurons were examined according to Dessi's method. Toxicity of SNP i.c.v. to mice and the prophylactic effect of i.c.v. MB were investigated with respect to the incidence of seizure and the mortality of mice within 24 h.

RESULTS

Ten min treatment of SNP 1 mmol.L-1 decreased the survival rate of murine cerebellar nerve cells from 92% of normal control to 35%. Incubation with cGMP 0.1 mmol.L-1 for 1 h declined the survival rate from 94% of normal to 40%. Injection i.c.v. SNP 20 nmol killed one tenth of the mice in 24 h, and SNP 30 nmol killed 11/13 of the mice. MB (100 nmol) i.c.v. injection protected 11/13 of the mice against seizure and death caused by SNP (30 nmol, i.c.v.), and completely eliminated the toxicity of SNP 20 nmol.

CONCLUSION

SNP and cGMP inhibit the vitality of murine neurons in vitro. MB injection i.c.v. markedly antagonizes the dose-dependent neuron-toxic effect of SNP in respect of convulsion and mortality of mice.

Characteristics of recombinant human butyrylcholinesterase

AIM

To study the biochemical-pharmacological properties of the recombinant human butyrylcholinesterase (rhBChE) and thereby to size up the potential possibility of using it as a detoxifying agent in succinylcholine intoxication.

METHODS

CHO-dhfr cells were transfected with plasmids by electroporation. BChE activity was determined colorimetrically by 5, 5'-dithiobis-(2-nitrobenzoic acid) (DTNB) method. Antigenicity was estimated by enzyme-linked immunosorbent assay and Western blot.

RESULTS

The maximal expression amounted to 25.83 ng.h-1/10(6) cells. The rhBChE was highly similar to the native human BChE (nhBChE) in terms of its catalytic property, substrate affinity, inhibitor sensitivity, reactivation, stability, and immunoreactivity with anti-nhBChE antibodies. Mice challenged with 1.5 lethal dose of succinylcholine preincubated with rhBChE survived without any symptoms of intoxication.

CONCLUSION

The rhBChE and nhBChE exhibit similar biochemical-pharmacological features. It is of potential value in practical use.

Nitric oxide and soman poisoning

AIM

To examine whether nitric-oxide (NO) is involved in the toxicity of soman.

METHODS

With pretreatments of icv L-arginine (Arg, the substrate of nitric-oxide synthase NOS), NG-nitro-L-arginine methyl ester (NAME, the inhibitor of NOS), the latency of seizure, and the mortality of mice induced by soman poisoning were examined. The activities of brain NOS in soman-intoxicated mice were measured.

RESULTS

In case of Arg pretreatments, the latency decreased (P < 0.05) from (5.2 +/- 1.8) min (control) to (4.3 +/- 0.8) min (Arg 160 nmol), and the mortality increased (P < 0.05) from 50% (control) to 81% (Arg 160 nmol). In case of NAME pretreatment, the latency increased (P < 0.01) from (4.0 +/- 1.1) min (control) to (14.5 +/- 5.0) min (NAME 2.20 mumol), and the mortality decreased (P < 0.05) from 87% (control) to 50% (NAME 2.20 mumol). The toxicity of soman in mice was enhanced by Arg and reduced by NAME all in a dose-dependent fashion. NAME antagonized the enhancement of soman poisoning by Arg. Intoxication of mice with soman increased the NOS activity in cerebrum, cerebellum, and hippocampus from 100% to 104% (P < 0.05), 115% (P < 0.01), and 111% (P < 0.01), respectively.

CONCLUSION

The onset of seizure and death of mice induced by soman poisoning are related to the NO messenger system.

Anionic subsite of active center of Torpedo acetylcholinesterase constructs a part of its conformational epitope

AIM

To study the structure-activity relationship of Torpedo acetylcholinesterase (AChE) and explore whether the anionic subsite of the active center is a constituent of the conformational epitope of enzyme.

METHODS

Using ELISA and enzyme inhibition test to examine the effect of 1-methyl-2-hydroxyiminomethylpyridium chloride (2-PAM), an anionic subsite probe of AChE, on the immunoreactivity between Torpedo AChE and its monoclonal antibody (McAb) 3F3.

RESULTS

McAb 3F3 did not react with 2-PAM-AChE complex. 2-PAM decreased the inhibitory rate of McAb 3F3 on AChE in a concentration-dependent fashion, but did not dissociate the McAb 3F3-AChE complex.

CONCLUSION

Anionic subsite of the active center of Torpedo AChE constructs a part of its conformational epitope.

Monoclonal antibody 3F3 against conformational epitope of Torpedo acetylcholinesterase

AIM

To study the type of epitope of native Torpedo acetylcholinesterase (AChE) directed by its monoclonal antibody (McAb) 3F3.

METHODS

Enzyme-linked immunosorbent assay (ELISA) was used for the assay of the reaction between antigen and antibody.

RESULTS

McAb 3F3 immunoreacted well with the native AChE, but not with the reduced- and alkylated-AChE (RA-AChE) at all. Soman did not interfere the binding of 3F3 with AChE molecule. The synthesized 24-peptide containing the active serine residue of the AChE active center did not react with McAb 3F3.

CONCLUSION

3F3 is a monoclonal antibody against the conformational epitope of Torpedo AChE active center, but dose not occupy the active serine residue of the enzyme.

The Goodpasture autoantigen. Structural delineation of two immunologically privileged epitopes on alpha3(IV) chain of type IV collagen

The family of type IV collagen comprises six chains numbered alpha1 through alpha6. The alpha3(IV) NC1 domain is the primary target antigen for autoantibodies from patients with anti-basement membrane disease and Goodpasture syndrome. Earlier peptide studies suggested that the last 36 amino acids of the alpha3 NC1 domain probably contains one recognition site for Goodpasture autoantibodies, and an algorithm analysis of secondary structure from a later study predicted a second possible upstream epitope near the triple helix junction. We have used several analytic approaches to evaluate the likelihood of two immunologic epitopes for the Goodpasture antigen. In our first set of studies, peptide antibodies directed against these two putative regions co-inhibited Goodpasture autoantibodies binding to denatured human alpha3(IV) NC1 monomer by nearly 80%, with the helix-junction region of the alpha3 NC1 domain contributing 26% of the binding sites and the C-terminal region contributing the remaining 50%. Second, both of these candidate regions are normally sequestered within the associated alpha3(IV) NC1 hexamer but become more visible for binding by anti-peptide antibodies upon their dissociation, a property that is shared by the Goodpasture autoantibodies. Third, segment deletions of recombinant alpha3 NC1 domain further confirmed the presence of two serologic binding sites. Finally, we looked more closely at the C-terminal binding region of the alpha3(IV) NC1 domain. Since the lysines in that region have been previously advanced as possible contact sites, we created several substitutions within the C-terminal epitope of the alpha3 NC1 domain. Substitution of lysines to alanines revealed lysines 219 and 229 as essential for antibody binding to this distal site; no lysines were present in the NC1 part of the helix-NC1 junction region. Substitutions involving arginine and cysteines to alanines in the same C-terminal region did not produce significant reductions in antibody binding. In summary, our findings characterize two Goodpasture epitopes confined to each end of the alpha3 NC1 domain; one is lysine-dependent, and the other is not. We propose, as a hypothetical model, that these two immunologically privileged regions fold to form an optimal pathogenic structure within the NC1 domain of the alpha3 chain. These sites are subsequently concealed by NC1 hexamer assembly of type IV collagen.

Lipoperoxidative injury to macrophages by oxidatively modified low density lipoprotein may play an important role in foam cell formation

Both oxidatively and malondialdehyde modified low density lipoprotein (Ox-LDL and MDA-LDL) could be recognized by the scavenger receptor and induce intracellular cholesteryl ester accumulation of macrophage. The cholesteryl ester accumulation caused by MDA-LDL could be largely cleared by high density lipoprotein (HDL3), but that caused by Ox-LDL could not be. Further studies showed that Ox-LDL and MDA-LDL all could decrease the binding capacity of HDL3 and increase intracellular thiobarbituric acid reactive substances (TBARS). When macrophages were first cultured with MDA-LDL and then in medium without LDL, the decreased binding capacity of HDL3 was somewhat recovered and the intracellular TBARS did not increase any more. However, if macrophages were first cultured with Ox-LDL, the binding capacity of H DL3 continued to decrease and intracellular TBARS continued to increase. There was a negative correlation (r = -0.81, P < 0.01) between the decreased binding capacity of HDL3 and the increased intracellular TBARS caused by Ox-LDL. These results imply that lipid peroxidative injury to macrophages caused by Ox-LDL play an important role in foam cell formation.

Comparative distribution of the alpha 1(IV), alpha 5(IV), and alpha 6(IV) collagen chains in normal human adult and fetal tissues and in kidneys from X-linked Alport syndrome patients

We have shown previously that the 5' ends of the genes for the alpha 5(IV) and alpha 6(IV) collagen chains lie head-to-head on Xq22 and are deleted in patients with Alport syndrome (AS)-associated diffuse leiomyomatosis. In this study, we raised a rabbit anti-human alpha 6(IV)chain antibody, demonstrated its specificity by the analysis of recombinant NC1 domains af all six type IV chains, and studied the distribution of the alpha 6(IV) chain in relation to the alpha 1(IV) and alpha 5(IV) chains in human adult and fetal tissues involved in AS and diffuse leiomyomatosis. The alpha 6(IV) chain colocalizes with the alpha 5(IV) chain in basement membranes (BMs) of many tissues, but not in glomerular BM. These data exclude the alpha 6(IV) chain as a site for AS mutations. The head-to-head genomic pairing of the alpha 5(IV) and alpha 6 (IV) genes implies coordinate transcription of the two genes. Differential localization of the alpha 5(IV) and alpha 6(IV) chains shows that the two chains are not always coordinately regulated. The alpha 6(IV) chain, together with the alpha 3(IV)-alpha 5(IV) chains, was absent from all renal BMs in eight patients with X-linked AS while the alpha 1(IV) and alpha 2(IV) chains were increased. The data support the existence of two independent collagen networks, one for the alpha 3(IV)-alpha 6(IV) chains and one for the alpha 1(IV) and alpha 2(IV) chains.

Characterization of a cis-acting regulatory element which silences expression of the class II-A beta gene in epithelium

Class II major histocompatibility complex (MHC) genes encode for alpha/beta chain pairs that are constitutively expressed principally on mature B cells and dendritic cells in mice. These gene products are easily induced on macrophages with cytokines, and may also aberrantly appear on the surface of epithelium during immune injury. The appearance of class II determinants in parenchymal tissue potentially renders these somatic cells capable of antigen presentation to circulating CD4+ T lymphocytes, and their absence may be protective for normal tissues expressing self-antigens. The low surface class II expression observed on parenchymal cells generally correlates with low levels of mRNA, suggesting that transcription rate is a major element in class II regulation. To understand the transcriptional mechanism maintaining low basal surface expression of class II in somatic cells, we transiently transfected mini-gene reporter constructs to study the regulation of the murine A beta promoter in a cultured renal epithelial cell line. We describe here a negative cis-acting regulatory region located between -552 and -489 bp upstream of the A beta cap site that silences the transcriptional activity of the A beta promoter in epithelial cells in an orientation-dependent manner, and is also able to silence a heterologous promoter. This region is not active in class II-expressing B cells (BAL-17) in culture, but is functional in two other murine class II-negative cell lines, fibroblasts and thymoma T cells. Using competition electrophoretic mobility shift assays, we have localized the core protein binding site within this region to an 8-10-bp response element, designated A beta NRE, at -543 to -534 bp. A nuclear extract from BAL-17 cells does not bind to this element. Mutation of this site abrogates the transcriptional silencing activity of the region. We conclude that the transcription of class II-A beta in parenchymal cells, and some lymphocytes, can be actively repressed by an upstream silencing element.

Epitopes recognized by anti-reduced and alkylated acetylcholinesterase antibodies

Peptides of the reduced and alkylated acetylcholinesterase (RA-AChE) from the electric organ of Torpediniformes Torpedo torpedo subjected to bromo-cynogen (CNBr) cleavage or/and peptic digestion conserved well the antigen-antibody reactivity with anti-RA-AChE monoclonal antibodies E9, F6, and F12, whereas peptides produced by CNBr and tryptic treatments lost all the reactivity. Periodate oxidation of the RA-AChE or glycopeptidase digestion of the CNBr cleaved RA-AChE did not change the antigen-antibody reactivity. It implied that the epitopes recognized by the 3 anti-RA-AChE monoclonal antibodies are all peptide determinants rather than carbohydrate determinants.

A monoclonal antibody marker for Alport syndrome identifies the Alport antigen as the alpha 5 chain of type IV collagen

The nephropathy of Alport syndrome is associated with unique abnormalities of glomerular basement membranes and is caused in many families by mutations in the X-chromosomal gene COL4A5, which encodes the alpha 5 chain of type IV collagen. We have previously reported that Alport epidermal and glomerular basement membranes fail to bind a monoclonal antibody, Mab A7, that reacts with normal epidermal and glomerular basement membranes, and that this abnormality is unique to Alport syndrome. The molecule in normal tissues that reacts with Mab A7 was termed the "Alport antigen". In the present study we used recombinant carboxyterminal noncollagenous (NC1) domains of the alpha 1, alpha 2, alpha 3, alpha 4 and alpha 5 chains of type IV collagen to determine the molecular identity of the Alport antigen. Mab A7 was found to bind specifically to the NC1 domain of the alpha 5 chain of type IV collagen, by ELISA and immunoblotting studies. This finding provides a molecular explanation for the utility of Mab A7 as a marker for the Alport basement membrane defect. Mab A7 can identify the Alport basement membrane defect in those patients in whom COL4A5 mutations prevent incorporation of alpha 5(IV) into basement membranes.

COL4A5 gene deletion and production of post-transplant anti-alpha 3(IV) collagen alloantibodies in Alport syndrome

Mutations in the COL4A5 gene encoding the alpha 5(IV) chain of type IV collagen have been implicated as the primary defect in X-linked Alport syndrome. Several kinds of mutations have been reported so far, spanning point mutations to complete gene deletions. About 5% of Alport patients, who undergo renal transplantation, develop anti-glomerular basement membrane (GBM) nephritis, causing loss of allograft function. In one such patient, COL4A5 gene deletion was recently identified. In the present study, the GBM constituent, targeted by the anti-GBM alloantibodies from the patient who had complete COL4A5 gene deletion was identified. Its identity was determined on the basis of circulating antibody binding to various GBM constituents, domains of bovine type IV collagen and recombinant NC1 domain of human type IV collagen. These results establish, for the first time, the absence of the alpha 5(IV) chain in Alport GBM and, in the same patient, the production of an alloantibody that is targeted to a different chain of type IV collagen, the alpha 3(IV) chain. These findings provide further support for the hypothesis that: (1) anti-alpha 3(IV) collagen alloantibodies mediate the allograft glomerulonephritis; and (2) COL4A5 gene mutations cause defective assembly of the alpha 3(IV) collagen alloantibodies mediate the allograft glomerulonephritis; and (2) COL4A5 gene mutations cause defective assembly of the alpha 3(IV) chain in Alport GBM, as reflected by the production of anti-alpha 3(IV) alloantibodies.

Purification and properties of acetylcholinesterase from human brain

Acetylcholinesterase from human caudate nucleus and partial thalamus was purified by using Con A-Sepharose, short-arm and long-arm ligand Sepharose affinity chromatographies. SDS-PAGE of the purified AChE under the reduced condition showed one main band, corresponding to a molecular weight of 66 kD. The purified AChE with a specific activity of 3384 U/mg protein represented 20% activity of the homogenate supernatant. Analysis of purified AChE by gradient slab PAGE and DISC-PAGE with activity staining revealed the existence of monomer, dimer, tetramer, hexamer and octomer of the enzyme. The isoelectric point of AChE ranged between pH 5.6 and 6.0. Con A-Sepharose affinity chromatography retained most of the applied AChE activity implying that the enzyme is a kind of glycoprotein. The isolated human brain AChE had no cross-immunoreactivity with 3F3 and weak cross-immunoreactivity with 2G8 and 1H11 anti-Torpedo AChE antibodies. Balb/c mice were immunized with human cerebellum AChE purified with Con A and short-arm ligand affinity chromatographies. The antiserum produced showed strong cross-immunoreactivity with Torpedo AChE but weak cross-immunoreactivity with human RBC membrane AChE. The purified human brain striatum AChE was reduced and alkylated, and then hydrolyzed by immobilized TPCK-treated trypsin. Trypsin peptides in the hydrolysate was separated by RP-HPLC. Several large peptide peaks and numbers of small peaks were observed. The large peaks showed obvious immunoreactivity with the mouse anti human cerebellum AChE antiserum.

Specificity of Goodpasture autoantibodies for the recombinant noncollagenous domains of human type IV collagen

Type IV collagen has recently emerged as a family composed of five known chains (alpha 1-alpha 5), each of which contains a carboxyl-terminal noncollagenous domain (NC1) of approximately 230 amino acids. The NC1 domain of the alpha 3(IV) chain is the probable target for autoantibodies in patients with Goodpasture syndrome (GP), as evidenced from studies employing bovine type IV collagen. In the present experiments, the specificity of GP antibodies for the five NC1 domains of human type IV collagen was determined by using recombinant NC1 domains as the antigen. cDNAs encoding each NC1 domain were expressed in E. coli as fusion proteins with a 6-histidine amino-terminal leader. The recombinant NC1 monomers r alpha 1(IV), r alpha 2(IV), r alpha 3(IV), r alpha 4(IV), and r alpha 5(IV) were purified by affinity chromatography to the fusion protein using a nickel resin column, and then characterized by electrophoresis and immunoblot analysis using chain-specific peptide antibodies. The specificity of GP antibodies from four patients to these recombinant proteins was then further evaluated by immunoblot analysis and enzyme-linked immunosorbent assay measurements. The GP antibodies reacted strongly with the r alpha 3(IV) NC1 domain but were not reactive when tested against the other four recombinant monomers. In contrast, neither antisera from patients with two other forms of autoimmune disease (anti-tubular basement membrane disease and Wegener's syndrome) nor normal control sera bound to any of the recombinant NC1 moieties. These results unambiguously establish that GP antibodies are specifically targeted to the NC1 domain of the alpha 3(IV) chain of human type IV collagen. The findings also establish a methodology for large scale preparation of r alpha 3(IV) NC1 domain for use in diagnostic tests and development of therapeutic procedures and offer a strategy for the elucidation of a more complete GP epitope by site-directed mutagenesis.

Molecular structure of a cross-reactive idiotype on autoantibodies recognizing parenchymal self

The autoimmune B cell repertoire in anti-tubular basement membrane (alpha TBM) disease is focused on the nephritogenic P1 domain of the 3M-1 target Ag in kidney and normally expresses a disease-modifying cross-reactive Id (IdX). The molecular structure of this Id was determined from a library of rat mAb alpha TBM/alpha 3M-1 by using anchor polymerase chain reactions. Our findings provide the first alignment of V region sequences for rat IgG and reveal that specificity for the P1 domain among alpha 3M-1 antibodies is derived from several recurring germ-line VH genes which have not undergone somatic mutation. The IdX in this repertoire localizes to the H chain on Western blot, and to the CDR3 region as deduced from the cDNA encoding several informative clones. Computer modeling of the Id reveals a conformational structure largely dependent on hydroxyl groups in or near turn position 4 of the H chain CDR3 region. These findings demonstrate that regulatory elements protective of autoimmunity are not encoded in the germ line as IdX, but rather emerge from a recombinatorial diversity engaged by the recognition of parenchymal self.

Molecular structure of a cross-reactive idiotype on autoantibodies recognizing parenchymal self

The autoimmune B cell repertoire in anti-tubular basement membrane (alpha TBM) disease is focused on the nephritogenic P1 domain of the 3M-1 target Ag in kidney and normally expresses a disease-modifying cross-reactive Id (IdX). The molecular structure of this Id was determined from a library of rat mAb alpha TBM/alpha 3M-1 by using anchor polymerase chain reactions. Our findings provide the first alignment of V region sequences for rat IgG and reveal that specificity for the P1 domain among alpha 3M-1 antibodies is derived from several recurring germ-line VH genes which have not undergone somatic mutation. The IdX in this repertoire localizes to the H chain on Western blot, and to the CDR3 region as deduced from the cDNA encoding several informative clones. Computer modeling of the Id reveals a conformational structure largely dependent on hydroxyl groups in or near turn position 4 of the H chain CDR3 region. These findings demonstrate that regulatory elements protective of autoimmunity are not encoded in the germ line as IdX, but rather emerge from a recombinatorial diversity engaged by the recognition of parenchymal self.

Human cDNA clones transcribed from an unusually high-molecular-weight RNA encode a new collagen chain

Human collagen (COL) cDNA clones were isolated from a library representing transcripts synthesized by an established rhabdomyosarcoma (RH) cell line. The 0.6-kb insert of the first isolate encodes a discontinuous collagenous sequence not homologous to type I-XVI COL chains. Sequencing of a second clone with a 4-kb insert revealed an open reading frame (ORF) of 2154 nucleotides. The deduced amino acid (aa) sequence begins with an 186-aa noncollagenous region containing seven cysteines (Cys). Several of the Cys and surrounding aa residues can be aligned with those in type XVI, XII and IX COL. Due to the presence of two long interruptions, the 524-aa collagenous region is separated into three subdomains that each have smaller interruptions of 1-6 aa. The protein terminates with an 8-aa noncollagenous peptide including an unusual single Cys which would be expected to form an interchain disulfide bond. Results of Northern blot hybridization suggest that the new COL chain may be uncommonly large since the clone identified a low-abundance RNA at least 12.4 kb in size. The gene coding for RH COL is located on human chromosome 6. It is now important to elucidate the role of this unusual COL in the infrastructure of extracellular matrix.

Biosynthetic and proliferative characteristics of tubulointerstitial fibroblasts probed with paracrine cytokines

Fibroblasts in parenchymal organs potentially contribute extracellular matrix to local fibrogenic processes. This contribution, in some circumstances, may be initiated by cytokines disseminated from inflammatory lesions. Different populations of fibroblasts, however, might respond distinctively to this cytokine bath depending on the microenvironment in which they reside. We have begun to explore this issue using syngeneic, low-passage fibroblasts cultured in serum-free media that were derived originally from the dermis (DFBs) and from tubulointerstitium (TFBs) of the kidney. Our findings indicate that, while fibroblasts from each compartment appear similar at the ultrastructural level, there are a variety of functional differences which distinguish their proliferative response, and their collagen secretory response (types I, III, IV, and V) following challenge with various doses of immune-relevant cytokines (TGF beta, EGF, IL-1, IL-2 and gamma IFN) in culture. DFBs, for example, express more surface EGF receptors than do TFBs, and, as a consequence, exhibit a more robust proliferative response to EGF in serum-free media. Unstimulated DFBs also secrete more collagen types I and III than TFBs, while unstimulated TFBs secrete more types IV and V. The expression of these collagens in TFBs was confirmed by Northern blot hybridization. When these sets of fibroblasts were further stimulated by cytokines, some of the cytokines not only differentially effect the secretion of various species of collagens within the same group of cells, but also between cells from populations which are anatomically distinct. DFBs, furthermore, at mid-level doses of cytokine, demonstrated a general trend towards less secretion of all types of collagen (particularly for TGF beta, EGF, and IL-2), while TFBs seemed less repressive. In TFBs the cytokine-induced responses for collagen types I and III tended to be discordant, and for types I and IV EGF inhibited, while TGF beta stimulated the secretory process. These findings speak collectively for the presence of a functional heterogeneity among organ-based populations of syngeneic fibroblasts in normal tissues.

Isolation and characterization of cDNA from renal tubular epithelium encoding murine Rantes

We have been interested in identifying proinflammatory molecules which might play a role in attracting monocytes and T cells to the kidney. Some of the new intercrines are potential candidates. In this report we have isolated cDNA encoding murine Rantes (MuRantes) from renal tubular epithelium (MCT cells). MuRantes is a 91 amino acid member of the -C-C- or intercrine beta subgroup of the Scy superfamily. The amino acid sequence for mature MuRantes was deduced from its coding cDNA and was found to be 90% homologous to its mature human counterpart (HuRantes). MCT epithelium expresses a single mRNA transcript for MuRantes of approximately 1100 bp. The MuRantes protein could be detected in cell lysates of MCT epithelium by western blotting and in the cytoplasm of MCT cells by immunofluorescence using a polyclonal antibody generated against HuRantes fusion protein. A search protocol using MuRantes-specific primers and cDNA amplification revealed that mRNAs for MuRantes are expressed additionally in syngeneic mesangial cells (MMC cells), whole kidney, liver, and spleen, as well as in nephritogenic antigen-specific CD4+ helper and CD8+ effector T cells. cDNA amplification studies also demonstrated a significant elevation in mRNA transcripts encoding MuRantes in response to the stimulation of MCT epithelium with TNF alpha and IL-1 alpha in culture, but not with TGF beta, gamma IFN, or IL-6. Our findings indicate that proximal tubular epithelium is an authentic source of MuRantes, and that transcripts encoding MuRantes are responsive to the modulating influence of paracrine factors having a known role in the development of parenchymal injury.

Analysis of the cDNA sequence encoding MHC-A beta in tubular epithelium from mouse kidney

Class II gene products of the major histocompatibility complex (MHC) are not expressed usually in abundance on normal epithelium. The cell surface visibility of such proteins for the immune system is thought to be limited protectively in order to minimize inflammation consequent to the recognition of self-antigens in parenchymal structures by T lymphocytes. In the current experiments we investigated whether the previously recognized sparseness of A beta on the surface of tubular epithelial cells might be accounted for by a protein coding difference deduced from the primary structure of its transcript compared with sequence from lymphoid cells that normally express A beta in generous amounts. We demonstrate, however, using clones obtained from a cDNA library prepared from tubular epithelium harvested from H-2s (A beta/alpha+; E beta/alpha-) mice susceptible to autoimmune interstitial nephritis, that the nucleotide sequence encoding the class II A beta chain in cells from both compartments is essentially identical. Our findings suggest that there is no primary structural aberrancy in the coding region of parenchymal A beta that would contribute to its low expression. The protective tolerance afforded by reduced numbers of class II molecules in normal tissues is, therefore, more likely the result of repressive regulatory processes.

Expression of homeobox genes in a proximal tubular cell line derived from adult mice

We have been studying the expression of several homeobox genes in cultures of proximal tubular epithelium (MCT cells) harvested from adult mus musculus. Hox genes 2.1, 2.3, and 3.3, in particular, are all expressed at low levels in resting MCT cells. The expression of Hox 2.1 and 3.3 were not influenced by mitogenic (epidermal growth factor: EGF, and platelet-derived growth factor: PDGF) nor by hypertrophogenic cytokines (angiotensin II: Ang II) in serum-free media. Transcripts for Hox 2.3, however, were elevated in MCT cells by Ang II. EGF, and serum treatment, as early as 30 minutes after their addition, whereas no change, or slight reductions were observed with transforming growth factor beta (TGF beta), PDGF, and gamma-interferon (gamma IFN). Hox 2.3 was also super-induced by serum, in the presence of cycloheximide, in cells rested previously in serum-free media, suggesting that new protein synthesis was not required for expressive augmentation. The induction of Hox 2.3, moreover, was not specific for tubular epithelium, since the gene could be activated in tubulointerstitial fibroblasts after treatment with EGF. These experiments collectively represent a first report regarding the characterization of transcripts encoding homeoboxes in adult cells derived from renal tissue. The putative DNA-binding properties of homeobox proteins in general, the prompt and rapid induction of Hox 2.3 by morphogenic cytokines in tubulointerstitial cells, and the observed effect of cycloheximide on this gene, all indicate that Hox 2.3 might have a role in the general activation of mature somatic cells, as an immediate early event. probably in the capacity of a nuclear trans-acting factor.

Lysis of herpes simplex virus-infected cells by lymphokine-activated killer cells

Activation of human peripheral blood mononuclear cells (PBMC) or murine splenocytes with recombinant interleukin-2 (rIL-2) has been found to be able to generate cells which are lytic in vitro for a variety of cells infected by herpes simplex virus (HSV). Lymphokine-activated killer (LAK) cells were generated by the incubation of human PBMC or murine splenocytes with 500 u/ml of rIL-2 for 3 to 4 days in a CO2 incubator at 37 degrees C. These cells were lytic to cultured tumor cell lines, yet sparing normal primary cell cultures as has been reported. Human PBMC infected with HSV, however, were susceptible to the lytic effect of these LAK cells. From 30 to 50 percent lysis of HSV-infected human PBMC was observed when the effector-to-target ratios were 40:1 and 100:1 respectively by four hr 51Cr-release assays. Similar cytolytic effect was observed when mouse embryonic fibroblasts (MEF) were infected with HSV and used as targets when rIL-2-activated mouse splenocytes were used as effectors. The cytolytic effects of LAK cells on the HSV-infected cells can be demonstrated even after lowering of NK activities by the treatment of effector cells with anti-NK antibody Leu-11b plus complement. Cytolytic effects were not restricted to the autologous system, and could be demonstrated in the heterologous system as well. Human LAK cells killed not only HSV-infected autologous PBMC but also infected mouse embryonic fibroblasts. However, mouse LAK cells exhibit species-specific cytotoxicity. In conclusion, it was demonstrated that LAK cells are cytolytic to HSV-infected cells in both human and murine systems.

Primary malignant rhabdoid tumor of the brain: CT characteristics

Primary malignant rhabdoid tumor of the brain is rare. The CT manifestations and differential diagnosis are discussed in one pathologically proven case.

[Aerobic metabolism of VX and mixed function oxidases]

In our preliminary study, it has been found that VX oxidase exists in the microsome fraction of rat liver and the catalytic reaction needs the participation of molecular oxygen and coenzyme I or II. In this paper, the data showed that deoxycholate inactivated both the mixed function oxidase and VX oxidase. The specific inhibitor proadifen of the mixed function oxidase also profoundly inhibited VX oxidase activity. The complex of VX and cytochrome P-450 exhibited typical difference spectrum of type I. Aniline competitively inhibited the inactivation of VX catalyzed by microsomes. These results indicate that VX is one of the substrates of mixed function oxidase. VX oxidase in the rat liver cells is exactly the mixed function oxidase.

Eruption effects of microdontia--a case report

A patient presented at the Department of Orthodontics, Medunsa Dental Hospital, complaining of "crooked teeth". On clinical examination it was evident that several teeth were unerupted. The absence of a normal eruption pattern of certain teeth as well as delayed eruption of others, resulted in a malocclusion.

Clonotypic heterogeneity in experimental interstitial nephritis. Restricted specificity of the anti-tubular basement membrane B cell repertoire is associated with a disease-modifying crossreactive idiotype

Experimental anti-tubular basement membrane (anti-TBM) disease is an autoimmune interstitial nephritis elicited in susceptible rodents after immunization with renal tubular antigen. The nephritogenic antigen in the immunizing preparation is 3M-1, a 48,000 Mr noncollagenous glycoprotein. The hallmarks of the renal lesion are the presence of anti-TBM antibodies (anti-TBM-Ab) and a dense mononuclear cell infiltrate. The anti-TBM B cell repertoire in this disease was analyzed using a library of 22 anti-TBM mAbs generated in a prototypically susceptible Brown Norway rat. These anti-TBM mAbs were all demonstrated to be 3M-1 specific and their characterization formed the basis for the following observations: (a) The size of the anti-TBM B cell population is estimated at 58 distinct clones; (b) by competitive inhibition criteria, all anti-TBM mAbs recognize the same (or spatially close) epitope(s) on 3M-1. This focused recognition was maintained in spite of considerable variability in affinity. Epitopic dominance could also be demonstrated in human polyclonal anti-TBM antisera from a patient with anti-TBM disease; and (c) a crossreactive idiotype was documented, and antisera directed toward this set of variable region determinants was shown to be effective as a prophylactic regimen to abrogate disease, and as a therapeutic modality to arrest the progression of disease; (d) analysis of VH gene families suggested biased usage of Q52- and 7183-like families, although at least three gene families are used in the anti-TBM-Ab response. Thus, the anti-TBM B cell compartment in BN rats is moderately large, but is primarily focused to a single epitope on the nephritogenic antigen and is associated with a disease-modifying crossreactive idiotype.