[Establishing and verifying the threshold value of HLA mixed antigen reagent screening test results]

Objective: To establish the threshold value of human leukocyte antigen (HLA) mixed antigen reagent screening test results, and to verify it by HLA single antigen reagent confirmation test results. Methods: The results of 2 255 serum samples tested for HLA antibodies by HLA mixed antigen reagent in the department of HLA Laboratory, the First Affiliated Hospital of Soochow University from October 2017 to December 2021 were retrospectively analyzed. Among them, 1 139 samples were also tested by single antigen HLA Class-Ⅰ reagent and 1 116 samples were also tested by single antigen HLA Class-Ⅱ reagent. Based on the same antigens coated with both reagents, the Mean Fluorescence Intensity (MFI) and Nomalized Background ratio (NBG ratio) of 12 HLA Class-Ⅰ beads and 5 HLA Class-Ⅱ beads in the HLA mixed antigen reagent and the MFI of 77 anti-HLA class-Ⅰ antibodies and 35 anti-HLA class-Ⅱ antibodies detected by HLA single antigen reagent were recorded. The MFI and NBG ratio of HLA mixed antigen reagent beads in 1 139 or 1 116 samples were segmented according to the positive rate of antibodyies detected by the single antigen reagent corresponding to the antigens coated with each HLA mixed antigen reagent bead, and the results of the HLA mixed antigen screening test were verified by the HLA single antigen reagent confirmation test. Results: The threshold values of MFI and NBG ratio of HLA mixed antigen reagent's 17 beads were established. The MFI of No. 1 to No. 17 beads of HLA mixed antigen reagent ranged from 26.86 to 21 925.58, and the NBG ratio ranged from 0 to 434.65. According to the positive detection rate of HLA single antigen reagent corresponding to the coated antigens, the MFI and NBG ratio of the beads of HLA mixed antigen reagent were divided into positive interval, suspicious positive interval, suspicious negative interval and negative interval. The positive rates of anti-HLA class-Ⅰ antibodies by HLA mixed antigen reagent and single antigen HLA Class-Ⅰ reagent were 87.5% (997/1 139) and 66.3% (755/1 139). The positive rates of anti-HLA class-Ⅱ antibodies were 63.4% (707/1 116) and 44.9% (501/1 116). In the samples with suspicious negative, suspicious positive and positive results of HLA class-Ⅰ、Ⅱ antibodies detected by HLA mixed antigen reagent, the positive detection rates of single antigen HLA Class-Ⅰ reagent were 14.9% (17/114), 41.3% (145/351) and 91.3% (590/646), respectively. The positive detection rates of single antigen HLA Class-Ⅱ reagent were 15.5% (58/375), 26.5% (81/306) and 88.8% (356/401), respectively. Conclusions: In this study, the threshold values of MFI and NBG ratio of HLA mixed antigen reagent screening test are established, and the threshold values are verified by the results of HLA single antigen reagent confirmation test. HLA mixed reagent screening test can be used for screening of HLA antibodies, and if necessary, it should be combined with HLA single antigen confirmatory test for clinical detection of HLA antibodies.

[Anticoagulation status and adherence in patients with atrial fibrillation hospitalized for ACS and the impact on 1-year prognosis: a multicenter cohort study]

Objective: For patients with atrial fibrillation (AF) complicated with acute coronary syndrome (ACS), both anticoagulant and antiplatelet therapy should be applied, but the use of anticoagulation therapy is still poor in these patients in China. The purpose of this study was to explore the status and adherence of antithrombotic therapy in AF patients with ACS and the impact on 1 year clinical outcomes. Methods: Patients with AF hospitalized for ACS were retrospectively included from 6 tertiary hospitals in China between July 2015 and December 2020. According to the use of anticoagulant drugs at discharge, patients were divided into two groups: anticoagulant treatment group and non-anticoagulant treatment group. Logistic regression model was used to analyze the main factors influencing the use of anticoagulant drugs in patients with atrial fibrillation complicated with ACS. Major adverse cardiac events (MACEs) were defined as all-cause death, non-fatal myocardial infarction or coronary revascularization, and ischemic stroke and Bleeding Academic Research Consortium (BARC) 3 bleeding events were also collected at 1 year after discharge. After propensity score matching, Cox proportional hazards models and Kaplan-Meier analysis were used to evaluate the effect of anticoagulant treatment and non-anticoagulant treatment on 1-year prognosis. The patients were divided into different groups according to whether anticoagulation was performed at discharge and follow-up, and the sensitivity of the results was analyzed. Results: A total of 664 patients were enrolled, and 273 (41.1%) were treated with anticoagulant therapy, of whom 84 (30.8%) received triple antithrombotic therapy, 91 (33.3%) received double antithrombotic therapy (single antiplatelet combined with anticoagulant), and 98 (35.9%) received single anticoagulant therapy. Three hundred and ninety-one (58.9%) patients were treated with antiplatelet therapy, including 253 (64.7%) with dual antiplatelet therapy and 138 (35.3%) with single antiplatelet therapy. After 1∶1 propensity score matching between the anticoagulant group and the non-anticoagulant group, a total of 218 pairs were matched. Multivariate logistic regression analysis showed that history of diabetes, HAS-BLED score≥3, and percutaneous coronary intervention were predictors of the absence of anticoagulant therapy, while history of ischemic stroke and persistent atrial fibrillation were predictors of anticoagulant therapy. At 1-year follow-up, 218 patients (79.9%) in the anticoagulant group continued to receive anticoagulant therapy, and 333 patients (85.2%) in the antiplatelet group continued to receive antiplatelet therapy. At 1-year follow-up, 36 MACEs events (13.2%) occurred in the anticoagulant group, and 81 MACEs events (20.7%) in the non-anticoagulant group. HR values and confidence intervals were calculated by Cox proportional risk model. Patients in the non-anticoagulant group faced a higher risk of MACEs (HR=1.802, 95%CI 1.112-2.921, P=0.017), and the risk of bleeding events was similar between the two group (HR=0.825,95%CI 0.397-1.715, P=0.607). Conclusions: History of diabetes, HAS-BLED score≥3, and percutaneous coronary intervention are independent factors for the absence of anticoagulant therapy in patients with AF complicated with ACS. The incidence of MACEs, death and myocardial infarction is lower in the anticoagulant group, and the incidence of bleeding events is similar between the two groups. The risk of bleeding and ischemia/thrombosis should be dynamically assessed during follow-up and antithrombotic regiments should be adjusted accordingly.

[Singapore's healthy aging policy and implications for China]

Population ageing has become a major social issue of concern worldwide in recent years, with significant implications for national economic and social development. Globally, Singapore is one of the first countries to address ageing as a population issue and has implemented relatively well-developed initiatives to promote healthy ageing. Similar to China, Singapore has a sharp decline in the total fertility rate, resulting in changes in the population structure. This paper briefly introduces Singapore's healthy ageing measures, summarizes Singapore's practical measures and coping concepts in scientific research on ageing, healthcare programs for the elderly, elderly -friendly environment construction, artificial intelligence big data application, and puts forward that China should pay attention to the effectiveness of population growth incentive measures, pay attention to the scientific and technological response, increase the development and application of artificial intelligence, improve primary health care and long-term health care, and update scientific concepts.

Changes in Gut Microbiota by the Lactobacillus casei Anchoring the K88 Fimbrial Protein Prevented Newborn Piglets From Clinical Diarrhea

In the last 20 years, accumulating evidence indicates that the gut microbiota contribute to the development, maturation, and regulation of the host immune system and mediate host anti-pathogen defenses. Lactobacillus casei (L.casei) is a normal flora of the gastrointestinal tract in mammals and, as a great mucosal delivery vehicle, has wide use in bioengineering. However, the diarrhea prevention role of commensal intestinal microbiota interfered by the recombinant L.casei (rL.casei) in newborn piglets is not well understood. In our study, newborn piglets orally fed with the rL.casei surface displayed the fimbrial protein K88 of enterotoxigenic Escherichia coli (ETEC) and their feces were collected for a period of time after feeding. The next-generation sequencing of these fecal samples showed that the relative abundance of L.casei was significantly increased. The oral administration of rL.casei altered the intestinal microbial community as evidenced by altered microbial diversity and microbial taxonomic composition. Remarkably, the functional enhancing of the intestinal bacterial community by rL.casei was positively correlated with membrane transport, replication, and repair (p < 0.05). The specific antibody detection indicates that high levels of anti-K88 secretory immunoglobulin A (sIgA) were induced in fecal samples and systemic immunoglobulin G was produced in serum. The diarrhea rate in piglets caused by ETEC K88 was decreased by about 24%. Thus, the oral administration of rL.casei not only activated the mucosal and humoral immune responses in vivo but also contributed to shape the intestinal probiotics in newborn piglets and to significantly reduce the diarrhea rates of newborn piglets.

Picrasma quassioides Extract Elevates the Cervical Cancer Cell Apoptosis Through ROS-Mitochondrial Axis Activated p38 MAPK Signaling Pathway

BACKGROUND/AIM

Picrasma quassioides (P. quassioides) is used in traditional Asian medicine widely for the treatment of anemopyretic cold, eczema, nausea, loss of appetite, diabetes mellitus, hypertension etc. In this study we aimed to understand the effect of P. quassioides ethanol extract on SiHa cervical cancer cell apoptosis.

MATERIALS AND METHODS

The P. quassioides extract-induced apoptosis was analyzed using the MTT assay, fluorescence microscopy, flow cytometry and western blotting.

RESULTS

P. quassioides extract induced cellular apoptosis by increasing the accumulation of cellular and mitochondrial reactive oxygen species (ROS) levels and inhibiting ATP synthesis. Pretreatment with N-Acetylcysteine (NAC), a classic antioxidant, decreased the intracellular ROS production and inhibited apoptosis. In addition, the P38 MAPK signaling pathway is a key in the apoptosis of SiHa cells induced by the P. quassioides extract.

CONCLUSION

The P. quassioides extract exerts its anti-cancer properties on SiHa cells through ROS-mitochondria axis and P38 MAPK signaling. Our data provide a new insight for P. quassioides as a therapeutic strategy for cervical cancer treatment.

The compound 2-benzylthio-5,8-dimethoxynaphthalene-1,4-dione leads to apoptotic cell death by increasing the cellular reactive oxygen species levels in Ras-mutated liver cancer cells

The aim of the present study was to verify the pro-apoptotic anticancer potential of several 5,8-dimethoxy-1,4-phthoquinone (DMNQ) derivatives in Ras-mediated tumorigenesis. MTT assays were used to detect cellular viability and flow cytometry was performed to assess intracellular reactive oxygen species (ROS) levels and apoptosis. The expression levels of proteins were detected via western blotting. Among the 12 newly synthesized DMNQ derivatives, 2-benzylthio-5,8-dimethoxynaphthalene-1,4-dione (BZNQ; component #1) significantly reduced cell viability both in mouse NIH3T3 embryonic fibroblasts cells (NC) and H-Ras^G12V transfected mouse NIH3T3 embryonic fibroblasts cells (NR). Moreover, BZNQ resulted in increased cytotoxic sensitivity in Ras-mutant transfected cells. Furthermore, the reactive oxygen species (ROS) levels in H-Ras^G12V transfected HepG2 liver cancer cells (HR) were significantly higher compared with the levels in HepG2 liver cancer cells (HC) following BZNQ treatment, which further resulted in increased cellular apoptosis. Eliminating cellular ROS using an ROS scavenger N-acetyl-L-cysteine markedly reversed BZNQ-induced cellular ROS accumulation and cell apoptosis in HC and HR cells. Western blotting results revealed that BZNQ significantly downregulated H-Ras protein expression and inhibited the Ras-mediated downstream signaling pathways such as protein kinase B, extracellular signal-related kinase and glycogen synthase kinase phosphorylation and β-catenin protein expression. These results indicated that the novel DMNQ derivative BZNQ may be a therapeutic drug for Ras-mediated liver tumorigenesis. The results of the current study suggest that BZNQ exerts its effect by downregulating H-Ras protein expression and Ras-mediated signaling pathways.

Peroxiredoxin II Inhibits Alcohol-induced Apoptosis in L02 Hepatocytes Through AKT/β-Catenin Signaling Pathway

BACKGROUND

Peroxiredoxin II (PRDX2) performs unique roles in cells. It can reduce peroxides through cysteine residues, and helps prevent the effects of oxidative stress on cells. It is closely related to the occurrence and development of various diseases, especially alcoholic liver injury and even liver cancer. The metabolism of alcohol in hepatocytes leads to the increase in the levels of reactive oxygen species (ROS), oxidative stress, injury, and apoptosis. Therefore, this study focused on the investigating the protection conferred by PRDX2 against alcohol-induced apoptosis of hepatocytes.

MATERIALS AND METHODS

PRDX2 inhibition of alcohol-induced apoptosis in L02 hepatocytes was analyzed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, fluorescence microscopy, flow cytometry, western blotting and hematoxylin and eosin staining.

RESULTS

The results showed that the levels of reactive oxygen species, protein kinase B, β-catenin, B-cell lymphoma-2 (BCL2), BCL-XL, BCL2-associated X, cleaved caspase-3, and cleaved poly (ADP-ribose) polymerase in PRDX2-silenced cells were increased significantly after the treatment of cells with ethanol. Similar results were obtained in an in vivo Prdx2-knockout mouse model of alcoholic liver injury. Therefore, PRDX2 may regulate the phosphorylation of the AKT signal protein by eliminating reactive oxygen species from cells, and it inhibits the downstream mitochondria-dependent apoptosis pathway, and, thereby, the apoptosis of cells.

CONCLUSION

Thus, PRDX2 may be a potential molecular target for the prevention and treatment of alcoholic liver injury.

Anti-tumor Properties of Picrasma quassioides Extracts in H-RasG12V Liver Cancer Are Mediated Through ROS-dependent Mitochondrial Dysfunction

BACKGROUND

Picrasma quassioides (PQ) is a traditional Asian herbal medicine with anti-tumor properties that can inhibit the viability of HepG2 liver cancer cells. H-Ras is often mutated in liver cancer, however, the effect of PQ treatment on H-Ras mutated liver cancer is unclear. This study aimed to investigate the role of PQ on ROS accumulation and mitochondrial dysfunction in H-ras mutated HepG2 (HepG2^G12V) cells.

MATERIALS AND METHODS

PQ ethanol extract-induced HepG2^G12V apoptosis was analyzed by the MTT assay, fluorescence microscopy, flow cytometry and western blotting.

RESULTS

PQ treatment affected cell migration and colony formation in HepG2^G12V cells. Cleaved-caspase-3, cleaved-caspase-9 and BCL2 associated agonist of cell death (BAD) expression levels were increased, while the levels of B-cell lymphoma-extra large (Bcl-xL) were decreased with PQ treatment. PQ treatment led to a reduction of H-Ras expression levels in liver cancer cells, thus reducing their abnormal proliferation. Furthermore, it led to increased expression levels of Peroxiredoxin VI, which regulates the redox signal in cells.

CONCLUSION

Taken together these results provide a new functional significance for the role of PQ in treating HepG2^G12V liver cancer.

Peroxiredoxin I deficiency increases pancreatic β‑cell apoptosis after streptozotocin stimulation via the AKT/GSK3β signaling pathway

Apoptosis of pancreatic β-cells is involved in the pathogenesis of type I and II diabetes. Peroxiredoxin I (Prx I) serves an important role in regulating cellular apoptosis; however, the role of Prx I in pancreatic β-cell apoptosis is not completely understood. In the present study, the role of peroxiredoxin 1 (Prx I) during streptozotocin (STZ)-induced apoptosis of pancreatic β-cells was investigated. The expression level of Prx I was decreased by STZ treatment in a time-dependent manner, and apoptosis of Prx I knockdown MIN6 cells was increased by STZ stimulation, compared with untransduced MIN6 cells. Furthermore, an intraperitoneal injection of STZ increased pancreatic islet damage in Prx I knockout mice, compared with wild-type and Prx II knockout mice. AKT and glycogen synthase kinase (GSK)-3β phosphorylation significantly decreased following Prx I knockdown in MIN6 cells. However, phosphorylated β-catenin and p65 levels significantly increased after STZ stimulation, compared with untransduced cells. The results of the present study indicate that deletion of Prx I mediated STZ-induced pancreatic β-cell death in vivo and in vitro by regulating the AKT/GSK-3β/β-catenin signaling pathway, as well as NF-κB signaling. These findings provide a theoretical basis for treatment of pancreatic damage.

Peroxiredoxin I deficiency increases keratinocyte apoptosis in a skin tumor model via the ROS-p38 MAPK pathway

Keratinocyte hyperproliferation is an essential link in skin cancer pathogenesis. Peroxiredoxin I (Prx I) is known to regulate cancer cell proliferation, differentiation, and apoptosis, but its role in skin cancer remains unclear. This study aimed to elucidate the role and mechanism of Prx I in skin cancer pathogenesis. Dimethylbenz[a]anthracene (DMBA) and 12-O-tetradecanoyl-phorbol-13-acetate (TPA) were used to create a skin tumor model of the initiation/promotion stage of cancer. The role of Prx I in H₂O₂-induced keratinocyte apoptosis was also investigated. After DMBA/TPA treatment, Prx I deficiency was significantly associated with less skin tumors, lower Bcl-2 expression, and higher p-p38 and cleaved caspase-3 expressions in Prx I knockout tumors than in wild-type controls. H₂O₂ stimulation caused more cellular apoptosis in Prx I knockdown HaCaT cells than in normal HaCaT cells. The signaling study revealed that Bcl-2, p-p38, and cleaved caspase-3 expressions were consistent with the results in the tumors. In conclusion, the deletion of Prx I triggered the DMBA/TPA-induced skin tumor formation in vivo and in vitro by regulating the reactive oxygen species (ROS)-p38 mitogen-activated protein kinase (MAPK) pathway. These findings provide a theoretical basis for treating skin cancer.

Structure and Properties of PSf Hollow Fiber Membranes with Different Molecular Weight Hyperbranched Polyester Using Pentaerythritol as Core

A homologous series of hyperbranched polyesters (HBPEs) was successfully synthesized via an esterification reaction of 2,2-bis(methylol)propionic acid (bis-MPA) with pentaerythritol. The molecular weights of the HBPEs were 2160, 2660, 4150 and 5840 g/mol, respectively. These HBPEs were used as additives to prepare polysulfone (PSf) hollow fiber membranes via non-solvent induced phase separation. The characteristic behaviors of the casting solution were investigated, as well as the morphologies, hydrophilicity and mechanical properties of the PSf membranes. The results showed that the initial viscosities of the casting solutions were increased, and the shear-thinning phenomenon became increasingly obvious. The demixing rate first increased and then decreased when increasing the HBPE molecular weight, and the turning point was 2660 g/mol. The PSf hollow fiber membranes with different molecular weights of HBPEs had a co-existing morphology of double finger-like and sponge-like structures. The starting pure water contact angle decreased obviously, and the mechanical properties improved.

A Facile Way to Prepare Hydrophilic Homogeneous PES Hollow Fiber Membrane via Non-Solvent Assisted Reverse Thermally Induced Phase Separation (RTIPS) Method

Sulfonated polyethersulfone (SPES) was used as an additive to prepare hydrophilic poly(ethersulfone) (PES) hollow fiber membranes via non-solvent assisted reverse thermally induced phase separation (RTIPS) process. The PES/SPES/N,N-dimethylacetamide (DMAc)/ polyethylene glycol 200 (PEG200) casting solutions are lower critical solution temperature (LCST) membrane forming systems. The LCST and phase separation rate increased with the increase of SPES concentrations, while the casting solutions showed shear thinning. When the membrane forming temperature was higher than the LCST, membrane formation mechanism was controlled by non-solvent assisted RTIPS process and the also membranes presented a more porous structure on the surface and a bi-continuous structure on the cross section. The membranes prepared by applying SPES present higher pure water flux than that of the pure PES membrane. The advantages of the SPES additive are reflected by the relatively high flux, good hydrophilicity and excellent mechanical properties at 0.5 wt.% SPES content.

Insulin neuroprotection and the mechanisms

Objective:

To analyze the mechanism of neuroprotection of insulin and which blood glucose range was benefit for insulin exerting neuroprotective action.

Data Sources:

The study is based on the data from PubMed.

Study Selection:

Articles were selected with the search terms “insulin”, “blood glucose”, “neuroprotection”, “brain”, “glycogen”, “cerebral ischemia”, “neuronal necrosis”, “glutamate”, “γ-aminobutyric acid”.

Results:

Insulin has neuroprotection. The mechanisms include the regulation of neurotransmitter, promoting glycogen synthesis, and inhibition of neuronal necrosis and apoptosis. Insulin could play its role in neuroprotection by avoiding hypoglycemia and hyperglycemia.

Conclusions:

Intermittent and long-term infusion insulin may be a benefit for patients with ischemic brain damage at blood glucose 6–9 mmol/L.

[Molecular mechanism of ORFV intervention strategies based on the UPS of host cell: a review]

In order to compete the antiviral effects of the host cell in the process of infection, ORFV(known as Orf virus) relies on a series of functional genes developed through long-term population evolution, such as interferon resistance genes, Bcl-2 protein genes and cell cycle inhibitor gene and so on, with these weapons this virus is able to effectively counteract immune clearance and immune regulation from a host cell. Concurrently, ORFV also focuses on exploiting signal transduction pathways of the ubiquitin-proteasome system(UPS), circumvents the intracellular signal transduction and CD8+ T activation, for shielding virus particles towards maturation and releasing outside. This review introduced inner link between the UPS of host cell and intervention mechanism by virus, and analyzed the key roles of certains components in UPS, these all together showed the evolution tendency of ORFV that was involved in the designing of inhibition to immune response and for intracellular immune escape upon the selection pressure in host cell infected.

Development, characterization and anti-tumor effect of a sequential sustained-release preparation containing ricin and cobra venom cytotoxin

Cobra venom cytotoxin (CVC) loaded in poly (lactide-co-glycolide) (PLGA) microspheres was mixed with ricin and encapsulated in a thermosensitive PLGA-PEG-PLGA hydrogel for this study. This sequential sustained-release preparation (SSRP) containing ricin and CVC could avoid burst release effect of CVC from microspheres. In addition, in SSRP, the two biotoxins have different drug release rates and antitumor mechanisms, which can be complementary to each other. Ricin has a faster release rate than CVC. It can combine with the tumor cell membrane and enter the cell, inhibiting protein synthesis within 2 weeks. Whereas CVC releases slowly in 5 weeks directly dissolving the tumor cell membrane and killing the cells which are less-sensitive to ricin. The in vivo experiments showed that intratumoral injection of SSRP could inhibit hepatocellular carcinoma growth significantly, and the tumor growth inhibition rate reached 73.5%. It appears that a new medicine preparation for cancer local treatment should be further studied for clinical applications.

[Ultrasonographic appearance of experimental testicular ischemia and protective effect of allopurinol]

OBJECTIVE

To investigate the correlation of the ultrasonographic appearance of different degrees of experimentally induced acute unilateral testicular ischemia with the protective effect of allopurinol.

METHODS

Forty-two male white rabbits were equally randomized into 7 groups: sham-operation control, ischemic A, B and C, and treatment D, E and F. Models of different degrees of unilateral testicular ischemia were established in the ischemic and treatment groups under the dynamic observation by color Doppler ultrasound. The ischemic testes showed slightly decreased homogeneous echoes and flow signals in groups A and D, obviously decreased heterogeneous echoes and flow signals in groups B and E, and radial or fragmental low-echo areas and disappearance of flow signals in groups C and F. The ischemic groups received reperfusion after the appearance of the above ultrasonographic changes, while the treatment groups following the intraperitoneal injection of allopurinol at 200 mg/kg. Contrast-enhanced ultrasonography (CEUS) was performed on the bilateral testes before and 3 days after the reperfusion. After 3 days of breeding, the histological changes and malondialdehyde (MDA) contents of the ischemic testes were observed, and the correlation was analyzed between the protective effect of allopurinol and the ultrasonographic appearance of different degrees of acute unilateral testicular ischemia.

RESULTS

CEUS showed fast wash-in and fast wash-out in the sham-operation control group, slow wash-in and slow wash-out in groups A and B and extensive central filling defect in group C before the reperfusion. Fast wash-in and slow wash-out were observed in all the ischemic groups 3 days after the reperfusion, most obviously in group C. Groups D, E and F exhibited the same CEUS appearance as A, B and C before and 3 days after the reperfusion. Johnsen's scores were significantly increased in groups D (9.10 +/- 0.23) and E (7.03 +/- 0.20) in comparison with A (8.53 +/- 0.22) and B (5.82 +/- 0.33) (P < 0.05), but with no significant differences between C (2.30 +/- 0.53) and F (2.45 +/- 0.33) (P > 0.05). The rates of apoptosis were significantly decreased in groups D ([1.68 +/- 0.43]%) and E ([12.53 +/- 0.59]%) compared with A ([7.12 +/- 0.84]%) and B ([20.87 +/- 1.59]%) (P < 0.05), but with no significant differences between C ([52.93 +/- 2.62 ]%) and F ([51.23 +/- 2.53 ]%) (P > 0.05). Significant decreases of MDA contents in the ischemic testes were observed in groups D ([0.64 +/- 0.05] nmol/mg prot), E ([1.59 +/- 0.06] nmol/mg prot) and F ([3.10 +/- 0.17] nmol/mg prot) in comparison with A ([1.38 +/- 0.07] nmol/mg prot), B ([2.11 +/- 0.08] nmol/mg prot) and C ([3.25 +/- 0.14] nmol/mg prot) (P < 0.05).

CONCLUSION

Allopurinol contributes to the recovery of spermatogenesis when testicular ischemia is sonographically shown to be mild or moderate, but produces no significant effect when it is shown to be severe. Ultrasonography helps to choose the right therapy of testicular torsion and predict spermatogenesis of ischemic testes after reperfusion.

Studies on Mucosal Immunity Induced by Transmissible Gastroenteritis Virus Nucleocapsid Protein Recombinant Lactobacillus casei in Mice and Sow

Mucosal immunity plays an important role in protecting pigs against transmissible gastroenteritis virus (TGEV) infection. To elicit mucosal immune response against TGEV, we developed a surface antigen display system using the poly-[.gamma]-glutamate synthetase A (pgsA) protein of Bacillus subtilis as an anchoring matrix to express recombinant fusion proteins of pgsA and nucleocapsid protein of TGEV in Lactobacillus casei. Surface location of fusion protein was verified by ELISA and indirect immunofluorescence test. Oral and intranasal inoculations of pregnant sow and mice with recombinant L. casei resulted in high levels of serum immunoglobulin G (IgG) and secretory immunoglobulin A (sIgA) against recombinant N protein as demonstrated by ELISA. More importantly, the level of specific sIgA in colostrum significantly increased compared with that of IgG. The serum IgG levels of the piglets increased after suckling colostrum produced by sows was previously inoculated with recombinant L. casei. These results indicate that immunization with recombinant L. casei expressing TGEV N protein on its surface elicited high levels of specific sIgA and circulating IgG against TGEV N protein.

[Correlation between sonographic appearance of experimental testicular ischemia and histological changes of the testis after reperfusion]

OBJECTIVE

To discuss the correlation between sonographic appearance of different degrees of acute unilateral testicular ischemia and histological changes of the testis after reperfusion.

METHODS

Thirty-two male rabbits were equally divided into a control (sham operation) group and 3 ischemia groups. Unilateral testicular ischemia models were established under the color Doppler ultrasound (CDU) observation and allocated according to different degrees of ischemia to Group A (with homogeneous echoes and slightly decreased flow signals), B (with heterogeneous echoes and obviously decreased flow signals) and C (with radial or small-shredded low echoes and absence of flow signals). Then contrast-enhanced ultrasonography (CEUS) was performed, followed by reperfusion of the ischemic testes. A month later, the histological changes of the testes were observed and the correlation of the histological changes with the sonographic and CEUS manifestations was analyzed.

RESULTS

Concerning the CEUS parameters such as the arrival time (AT), reperfusion rate, time-to-peak (TTP), half descent time (DT/2) of the ischemic testes, Groups A and B showed significant differences from the control group (P < 0.05). The peak-base difference (PBD) was significant in Group B (P < 0.05) but not in A (P > 0.05), and no enhancement was seen in Group C. As for Johnson's scores obtained 1 month later, Group A exhibited no significant difference (8.70 +/- 0.39) (P > 0.05), Group B showed significant difference (6.01 +/- 0.88) (P < 0.05), and Group C extremely significant difference (3.16 +/- 1.05) (P< 0.001) from the control group (9.10 +/- 0.11).

CONCLUSION

CEUS is superior to CDU in evaluating the perfusion of testicular ischemia. Sonographic appearances of testicular ischemia are significantly correlated with histological changes of the testis after reperfusion. Ultrasonography helps to predict the spermatogenetic function of ischemic testes after reperfusion.

Color Doppler velocity profile and contrast-enhanced ultrasonography in assessment of liver cirrhosis

BACKGROUND

This study was designed to probe the clinical value in assessing the degree of liver cirrhosis by using the arrival time of contrast agent in the right portal vein in contrast-enhanced ultrasonography, as well as the velocity and flow volume in the right portal vein using the color Doppler velocity profile technique.

METHODS

Twenty-eight patients with HBV post-hepatic cirrhosis were grouped into compensated (13 patients) and decompensated cirrhosis (15); 30 patients without hepatic cirrhosis served as controls. Written informed consent was obtained from each patient. All the patients with hepatic cirrhosis were pathologically confirmed by percutaneous biopsy. SonoVue was injected to detect the arrival time in the right portal vein. The velocity and flow volume in the right portal vein were measured. The value of each parameter was compared for correlation analysis.

RESULTS

The arrival time in the right portal vein in the cirrhosis group was much longer than that in the control group (24.92+/-1.34 vs. 20.81+/-0.55 sec, respectively, P<0.01). The mean velocity, maximal velocity and flow volume in the cirrhosis group were much lower than those in the control group (10.64+/-0.84 vs. 14.78+/-0.71 cm/sec, 13.68+/-1.02 vs. 17.30+/-0.68 cm/sec and 358.72+/-23.63 vs. 438.61+/-16.86 ml/min, respectively, P<0.01). With the development of cirrhosis, the arrival time in the right portal vein was longer (P<0.05), and the velocity and flow volume was lower (P<0.01). There was a negative correlation between arrival time and mean velocity, maximal velocity and flow volume in the right portal vein in the cirrhosis group (r=-0.547, P<0.01; r=-0.508, P<0.05; r=-0.471, P<0.05, respectively).

CONCLUSIONS

With the development of liver cirrhosis, the arrival time of contrast agent in the right portal vein is gradually prolonged, whereas the velocity and flow volume in this vein decreases markedly, and there is a negative correlation between the results of the two methods.

Effect of fatty liver background on contrast-enhanced ultrasonographic appearance of focal nodular hyperplasia

BACKGROUND

Focal nodular hyperplasia (FNH) is increasingly diagnosed as a result of the advances in imaging studies such as contrast-enhanced ultrasonography (CEUS), enhanced computed tomography and magnetic resonance imaging. However, FNH with atypical features can be difficult to differentiate from other benign and malignant tumors. The aim of this study was to investigate the influence of fatty liver background on the CEUS characteristics of FNH.

METHODS

Twenty-six patients with FNH were divided into two groups: group A included 14 patients with fatty liver and group B included 12 patients with normal liver background. Conventional two-dimensional ultrasonography and color Doppler flow imaging (CDFI) were conducted and followed by real-time dual-frame CEUS.

RESULTS

On two-dimensional ultrasonography, hypo-echoic nodules were present in most of the patients in group A (12/14) and hyperechoic nodules in most of those in group B (7/12). The difference in the nodule echotextures between the two groups was statistically significant (P<0.05). Nodules with centrifugal blood flow signals on CDFI were found in 6 of the 14 patients in group A and 5 of the 12 in group B (P>0.05). On CEUS, nodules with a central spoked-wheel-like enhancement pattern in the early arterial phase were observed in 8 patients in group A and those with an eccentric enhancement pattern in the remaining 6 patients. In this group, 3 patients had hypoechoic nodules in the delayed phase. Eleven of the 14 patients in this group were diagnosed accurately with CEUS. In group B, nodules with a rapid central spoked-wheel-like enhancement pattern in the early arterial phase were found in 8 patients by CEUS and those with rapid an eccentric enhancement pattern in 4. The nodules were found to be continuously enhanced in the delayed phase. All of the patients in group B were accurately diagnosed with CEUS.

CONCLUSIONS

A FNH nodule on a background of fatty liver may present a hypoechoic pattern on two-dimensional ultrasonography and a hypoechoic wash-out pattern in the delayed phase on CEUS. At this time, punch biopsy is needed for the diagnosis or differential diagnosis of FNH.

Three novel mutations of the PHEX gene in three Chinese families with X-linked dominant hypophosphatemic rickets

X-linked dominant hypophosphatemia (XLH, OMIM307800), the most prevalent form of inherited rickets in humans, is a dominant disorder of phosphate homeostasis characterized by growth retardation, rachitic and osteomalacic bone disease, hypophosphatemia, and renal phosphate wasting. The gene responsible for XLH was identified by positional cloning and designated PHEX (formerly PEX) to depict a phosphate-regulating gene homologous with endopeptidases on the X chromosome. Recently, extensive mutation analysis of the PHEX gene has revealed a wide variety of gene defects in XLH. The ethnic distribution of the mutations is very widespread but only a few mutations in Chinese have been reported. To analyze the molecular basis in three unrelated Chinese families with XLH, we determined the nucleotide sequence of the PHEX gene and fibroblast growth factor 23 (FGF23) gene of affected members. The serum FGF23 concentrations of these patients with XLH were also measured. Three different novel mutations were observed in these three families: one deletion mutation c.264delG causing p.W88 X; one missense mutation c.1673C>G causing p.P558A; one nonsense mutation c.1809G>A causing p.W603 X. Serum concentration of FGF23 in XLH patients of these three families was significantly higher than normal. The results suggest that PHEX gene mutations were responsible for XLH in these patients and these mutations may contribute to a higher serum FGF23 level.

Development and evaluation of enzyme-linked immunosorbent assay based on recombinant nucleocapsid protein for detection of porcine epidemic diarrhea (PEDV) antibodies

An enzyme-linked immunosorbent assays (ELISA) based on recombinant nucleocapsid (N) protein generated in Escherichia coli was evaluated for its sensitivity and specificity for diagnosis of porcine epidemic diarrhea (PEDV) infection. The N gene encoding the N protein was cloned and expressed as a fusion protein with His tag protein in E. coli. The recombinant N protein was migrated at 48 kDa and reacted with six histidine tag specific monoclonal antibody by immunoblotting. Recombinant N protein ELISA (rnELISA) demonstrated 98.7% specificities among (80) PEDV-free individuals, and 98% sensitivity ranging among (103) clinical samples with PEDV. On testing 884 field samples, an overall agreement of 88.3% was generated between the SN and rnELISA. Taken together, these results indicated that nucleocapsid protein may be a useful antigen for the sera-diagnosis of PEDV and it was also suggested that the ELISA is a highly sensitive and specific test for detecting antibodies to PEDV.

Ultrasound-guided fine needle biopsy of intrahepatic nodules and low elevation of AFP in early diagnosis of hepatocellular carcinoma

BACKGROUND

With the progress in early clinical treatment of hepatocellular carcinoma (HCC), early detection and diagnosis of HCC have been increasingly pressing. Combined alpha-fetoprotein(AFP) determination and ultrasonography has become the main method for the detection of small HCC; but the relationship between low elevation of AFP and pathologic findings of small HCC has not been well defined. The aim of this study was to assess the value of ultrasound-guided fine needle biopsy of intrahepatic nodules and low elevation of serum AFP in the early diagnosis of HCC.

METHODS

Fifty-nine patients with serum AFP exceeding 20 ng/ml and intrahepatic nodules varying from 0.8 cm to 5.0 cm in diameter who had been detected by ultrasonography underwent ultrasound-guided percutaneous fine needle biopsy, and cytological staining and histological sectioning were performed at the same time.

RESULTS

Among the 59 patients, 11 patients (18.6%) showed AFP level above 400 ng/ml, 5 (8.5%) from 200 ng/ml to 400 ng/ml, 18 (30.5%) from 50 ng/ml to 200 ng/ml and 25 (42.4%) from 20 ng/ml to 50 ng/ml. Follow-up demonstrated that 53 patients (89.8%) had a progressive increase of AFP level. In 58 patients (98.3%) cancer cells were found by cytological staining and/or histological sectioning.

CONCLUSIONS

In those patients with slightly increased or continuously positive AFP, hepatic carcinoma should be highly suspected when AFP increases gradually and intrahepatic nodules are detected by ultrasonography in follow-up. Once intrahepatic carcinoma nodules are suspected, ultrasound-guided fine needle biopsy should be performed as early as possible for early diagnosis and treatment.

Experimental and clinical assessment of percutaneous hepatic quantified ethanol injection in treatment of hepatic carcinoma

AIM: To detect the relationship between absolute ethanol injection quantity, the interval and formation of fibreboard, the curative effect in treatment of hepatocarcinoma and to evaluate the clinical application of percutaneous hepatic quantified ethanol injection (PHQEI) in treatment of hepatic carcinoma (HCC).

METHODS: (1) Experimental study: Twenty-four human hepatic carcinoma SMMC-7721 xenografted nude mice were randomly divided into three groups: Group A injected with quantified ethanol at short intervals (QESI), group B with quantified ethanol at long intervals (QELI) and group C with a small quantity of ethanol at long intervals (SQLI). The tumor tissues were sent for patho-histology and electron microscopic examinations. The diameters of tumors were measured with high frequency ultrasound before and after therapies and tumor growth index (TGI) was calculated. (2) Clinical study: Tumors of 122 cases of pathologically proved HCC were injected with quantified ethanol guided by ultrasound every 3-5 d 4-10 times per period of treatment. The quantity of ethanol was calculated according to the regressive equations where Y = 2.885X when the mass was ≤ 5 cm in diameter and Y = 1.805X when the mass was > 5 cm in diameter (X is the maximal diameter of the mass with the unit cm, Y is the ethanol quantity with the unit mL). The survival rates of 1, 2, 3 and 4 years and recurrent rates in situ as well as dystopia in the liver were calculated.

RESULTS: (1) Experimental study: TGI of QESI group (0.072 ± 0.018) and QELI group (0.094 ± 0.028) was apparently lower than that of SQLI group (1.982 ± 0.482) (P < 0.01). TGI of QESI group seemed to be lower than that of QELI group, but it was not markedly different (P > 0.05) between two groups. Severe degeneration and necrosis could be seen in QESI group by patho-histology examination. Coagulative necrosis could be seen in most tumors of QESI group and there were no residual cancer cells under electronic microscope, while the residual cancer and inflammatory cells and fibre tissues could be seen around the tumors of QELI group. Infiltration of inflammatory cells could be seen and fibre tissues were formed. (2) Clinical study: B mode ultrasound showed that 62.5% of tumors shrank after PHQEI. The survival rates of 1, 2, 3 and 4 years of the group with tumors ≤ 3 cm in diameter were higher than those of the group with tumors > 3 cm in diameter. The recurrent rates of tumors in situ of the former group were apparently lower than those of the latter group. The recurrent rates of tumors in dystopia in the liver of the former group were markedly lower than those of the latter group. The 122 cases underwent a total of 1221 PEI. There were no complications such as hemorrhage and severe heart, liver and kidney functional injuries except for 1 case of melena and 4 cases of jaundice who recovered after 1-2 wk under common therapies.

CONCLUSION: The experimental study shows quantified ethanol at intervals of 3-5 d could improve the curative effect of hepatocarcinoma. The clinical study shows PHQEI is an effective therapeutic method for HCC with few side-effects, and a low-cost. The treatment efficacy is more remarkable for tumors ≤ 3 cm in diameter.

Percutaneous intratumoral injection of traditional Chinese herbal compound medicine Star-99 in treatment of hepatocellular carcinoma of mice

BACKGROUND

Unresectable hepatocellular carcinoma (HCC) lacks effective therapy and entails very poor progress. In 1991, we found that Chinese herbal compound Star-99 has potentially effect on HCC. The purpose of this study was to probe the anti-cancer effect and the mechanism of focal injection of Chinese herbal compound Star-99 into HCC of mice.

METHODS

In 32 nude mice transplanted with human hepatocellular carcinoma SMMC-7721, 16 received hypodermic implant and the other 16 orthotopic liver transplant. They were randomly divided into three groups: Star-99 group (Chinese herbal compound, 16 mice), alcohol group (8) and saline group (8), respectively. Intratumoral injection of Star-99, alcohol and saline was carried out 10 days after transplantation of HCC. Twenty days after the first injection, the nude mice were killed after being injected every 5 days with a total of 4 injections in each mouse. Tumor tissues were examined pathologically or via an electron microscope and flow cytometrical (FCM) DNA analysis. The three diameters of the tumor were measured with high-frequency ultrasound before and after injection, and the growth index was calculated with the following formula: volume of tumor (after treatment-before treatment)/volume of tumor (before treatment). Double-blind method was applied in the experiment.

RESULTS

The growth index of the Star-99 group (0.068+/-0.022) and the alcohol group (0.079+/-0.024) was markedly lower than that of the saline group (4.345+/-1.453, P<0.01), but there was no significant difference between the Star-99 and alcohol groups. Coagulation (8/8) was the major pathological change in the alcohol group. In the Star-99 group, however, the phenomenon of lymphocytes attacking cancer cells could even be seen under the electron microscope. The typical apoptosis cells and apoptosis bodies as well as the collagen fibrae lined in mass could also be seen in the group (14/16). FCM DNA analysis showed that the rate of apoptosis in the Star-99 group (93.8%) was significantly higher than that in the alcohol (12.5%) and saline groups (12.5%) (P<0.01).

CONCLUSIONS

This study shows that Star-99 markedly inhibits and destructs hepatocellular cancer cells. Star-99 is effective to directly destroy the membrane, cytoplasm and nuclei of tumor cells, causing their crumbling, activate the immune function and inflammatory reaction of nude mice, and induce the apoptosis of cancer cells. The effect of Star99 is significantly different from that of alcohol that mainly causes coagulation of cancer cells. Star-99 is feasible in the treatment of HCC.

Neuron-specific Bcl-2 homology 3 domain-only splice variant of Bak is anti-apoptotic in neurons, but pro-apoptotic in non-neuronal cells

We have identified and characterized N-Bak, a neuron-specific isoform of the pro-apoptotic Bcl-2 family member Bak. N-Bak is generated by neuron-specific splicing of a novel 20-base pair exon, which changes the previously described Bak, containing Bcl-2 homology (BH) domains BH1, BH2, and BH3, into a shorter BH3-only protein. As demonstrated by reverse transcription-polymerase chain reaction and RNase protection assay, N-Bak transcripts are expressed only in central and peripheral neurons, but not in other cells, whereas the previously described Bak is expressed ubiquitously, but not in neurons. Neonatal sympathetic neurons microinjected with N-Bak resisted apoptotic death caused by nerve growth factor (NGF) removal, whereas microinjected Bak accelerated NGF deprivation-induced death. Overexpressed Bak killed sympathetic neurons in the presence of NGF, whereas N-Bak did not. N-Bak was, however, still death-promoting when overexpressed in non-neuronal cells. Thus, N-Bak is an anti-apoptotic BH3-only protein, but only in the appropriate cellular environment. This is the first example of a neuron-specific Bcl-2 family member.

Interleukin 10 aggravates experimental autoimmune myasthenia gravis through inducing Th2 and B cell responses to AChR

The damage of acetylcholine receptor (AChR) at neuromuscular junctions of experimental autoimmune myasthenia gravis (EAMG), an animal model of human MG, is mediated by B cells which require T cell help. The Th2 associated cytokine IL-10 suppresses production of cytokines released by Th1 cells and is considered for treatment of human autoimmune diseases. To evaluate the role of IL-10 in EAMG, rhIL-10 was administered daily to Lewis rats by the subcutaneous route starting at the day of immunization and continued for 7 weeks. IL-10 failed to abrogate EAMG at low dose (0.1 or 1 microg/day) and at the dose of 3 microg/day caused earlier onset and aggravated clinical signs of EAMG when compared to EAMG rats injected with PBS only. Although Th1 responses reflected by AChR-induced lymphocyte proliferation and levels of IFN-gamma secreting cells, as well as AChR-induced Th1 cytokine mRNA expression was suppressed, augmented IL-4 mRNA expression and AChR-specific B cell responses may play an important role in the failure of IL-10 to abrogate EAMG. This study implicates a critical precaution in planning immunotherapy of IL-10 in antibody-mediated autoimmune diseases, e.g. MG.

[The bacteria detection and drug sensitivity test from infected root canals]

OBJECTIVE

To provide bacteriological basis for curing infected root canals with sensitive drugs.

METHODS

We have made bacterial cultivation for 56 cases with infected root canals and drug sensitive test with agar dilution.

RESULTS

The rates of bacteria detection and positive rates from infected root canals were high. Anaerobia and aerobia were sensitive to different kinds of antibiotics.

CONCLUSION

Bacteria have close relation to infected root canals. Sensitive drugs should be selected in clinical treatment.

The role of LY49 NK cell subsets in the regulation of murine cytomegalovirus infections

The distributions and functions of NK cell subsets, as defined by the expression of Ly49 NK cell receptors, were examined in murine CMV (MCMV)-infected mice. MCMV induced a reduction in NK1.1+ cell number in the spleen and an increase in the peritoneal exudate cells. Within the splenic NK1.1+ population, proportional increases in Ly49A+ and Ly49G2+ cells but decreases in Ly49C+ and Ly49D+ cells were observed 3 days post-MCMV infection, but within the peritoneal NK1.1+ cell populations there were proportional decreases in Ly49A+ cells and increases in Ly49C+, Ly49D+, and Ly49G2+ cells. Lymphocytic choriomeningitis virus did not elicit a comparable NK cell subset distribution. Lymphokine-activated killer cells were sorted into different Ly49 NK cell subsets and adoptively transferred into C57BL/6 suckling mice. Regulation of MCMV synthesis in these suckling mice was shown to be an IFN-gamma-dependent, perforin- and Cmv-1-independent process, and each NK cell subset mediated anti-viral activity. In adult C57BL/6 mice, the control of MCMV in the spleen is mediated by a perforin-dependent mechanism, regulated in part by the Cmv-1 gene, which maps closely to the Ly49 family. In vivo depletions of either one or two of the Ly49 subsets in adult mice did not affect the ability of the residual NK cells to regulate MCMV synthesis. These data provide evidence of NK cell subset distribution and function in MCMV infection, but no individual subset was required for the Cmv-1-like regulation of MCMV synthesis.

Oltipraz chemoprevention trial in Qidong, Jiangsu Province, People's Republic of China

Oltipraz has been used clinically in many regions of the world as an antischistosomal agent and is an effective inhibitor of aflatoxin hepatocarcinogenesis in rats. This chemopreventive action of oltipraz results primarily from an altered balance in aflatoxin metabolic activation and detoxication. In 1995, a randomized, placebo-controlled, double-blind intervention was conducted in residents of Qidong, People's Republic of China, who are at high risk for exposure to aflatoxin and development of hepatocellular carcinoma. The major study objectives were to define a dose and schedule for oltipraz that would reduce levels of aflatoxin biomarkers in biofluids of the participants, and to further characterize dose-limiting side effects. Two hundred thirty-four healthy eligible individuals, including those infected with HBV, were randomized to receive either 125 mg oltipraz daily, 500 mg oltipraz weekly, or placebo. Blood and urine specimens were collected to monitor potential toxicities and evaluate biomarkers over the 8-week intervention and subsequent 8-week follow-up periods. Overall, compliance in the intervention was excellent; approximately 85% of the participants completed the study. Objective evaluation of adverse events was greatly facilitated by inclusion of a placebo arm in the study design. A syndrome involving numbness, tingling, and pain in the fingertips was the only event that occurred more frequently among the active groups (18 and 14% of the daily 125 mg and weekly 500 mg arms, respectively) compared to placebo (3%). These symptoms were reversible and could be relieved with non-steroidal antiinflammatory agents. A more complete understanding of the chemopreventive utility of oltipraz awaits completion of an assessment of the efficacy of oltipraz in modulating levels of aflatoxin biomarkers.

Synthetic peptides fail to induce nasal tolerance to experimental autoimmune myasthenia gravis

Nasal administration of Torpedo acetylcholine receptor (AChR) to Lewis rats prior to induction of experimental autoimmune myasthenia gravis (EAMG) is highly efficient in prevention of clinical weakness, and suppression of AChR-specific T and B cell responses. To identify possible antigenic determinants within the receptor which can modulate EAMG and anti-AChR response, we evaluated the effects of nasal administration of alpha 61-76, alpha 100-116, alpha 146-162, delta 354-367, and alpha 261-277 of Torpedo AChR at different doses on the tolerance induction against EAMG irrespective if given at lower, the same or higher doses than whole Torpedo AChR protein, that was confirmed to be highly efficient as tolerogen to EAMG. None of these peptides, neither administrated alone nor in combination, induced tolerance to EAMG. Peptide administration did not affect the levels or affinities of anti-AChR antibodies when compared with non-tolerized control EAMG rats, while administration of whole AChR protein affected both variables. The results may indicate that the T and B cell heterogeneity of AChR epitopes makes it difficult to induce tolerance using synthetic peptide.

Oltipraz chemoprevention trial in Qidong, People's Republic of China: modulation of serum aflatoxin albumin adduct biomarkers

In 1995, 234 adults from Qidong, People's Republic of China, were enrolled and followed in a Phase IIa 4-methyl-5-(N-2-pyrazinyl)-1,2-dithiole-3-thione (oltipraz) chemoprevention trial. Residents of this area are at high risk for development of hepatocellular carcinoma, in part due to consumption of aflatoxin-contaminated foods. The intervention was a randomized, placebo-controlled, double-blind study. Elements of the study design and clinical outcomes have been recently published (Jacobson et al, Cancer Epidemiol. Biomark. Prev., 6: 257-265, 1997). The primary objective was to conduct a preliminary assessment of the ability of oltipraz to modulate levels of a validated biomarker of aflatoxin exposure and of the risk of hepatocellular carcinoma by determining levels of aflatoxin-albumin adducts in sera. Healthy eligible individuals were randomized into three arms to receive p.o. 125 mg of oltipraz daily, 500 mg of oltipraz weekly, or placebo for 8 weeks. There were no consistent changes in biomarker levels in the placebo arm over the 16-week observation period, nor was any apparent effect observed in the arm receiving 125 mg of oltipraz each day. However, individuals receiving 500 mg of oltipraz once a week for 8 weeks showed a triphasic response to oltipraz. No effect was observed during the 1st month of the intervention, whereas a significant (P = 0.001) diminution in adduct levels was observed during the 2nd month of active intervention and during the lst month of follow-up. A partial rebound in adduct levels toward baseline values was observed during the 2nd month postintervention. Linear regression models up to week 13 confirmed a significant (P = 0.008) weekly decline of biomarker levels in the group receiving 500 mg of oltipraz once a week. However, despite these effects relative to baseline values within the 500-mg weekly arm, there were no statistically significant differences in biomarker trajectories between treatment arms. The genotype for glutathione S-transferase M1, an oltipraz-inducible isoform involved in the detoxification of aflatoxin B1, did not appear to affect either baseline levels or rates of decline in the biomarker. A follow-up Phase IIb trial with a longer intervention period will be necessary to determine the full extent to which aflatoxin biomarker burden can be reduced and whether diminution of biomarkers can be sustained over the long term.

Oltipraz chemoprevention trial in Qidong, People's Republic of China: study design and clinical outcomes

In 1995, 234 adults from Qidong, Jiangsu Province, People's Republic of China, where hepatocellular carcinoma is the leading cause of cancer deaths and exposure to dietary aflatoxins is widespread, were enrolled and followed in a Phase II chemoprevention trial. The goals of the study were to define a dose and schedule of oltipraz for reducing levels of validated aflatoxin biomarkers and to characterize dose-limiting toxicities. Healthy eligible individuals, including those infected with hepatitis B virus, were randomized to receive either 125 mg of oltipraz daily, 500 mg of oltipraz weekly, or placebo. Blood and urine specimens were collected to monitor toxicities and evaluate biomarkers over the 8-week intervention period and subsequent 8-week follow-up period. Unique trial aspects included a synchronous follow-up schedule, daily observed administration of all medications, timely international data transference, and use of biomarkers as outcomes. One hundred thirty-two participants took their medications without interruptions, approximately 77% contributed all nine urine samples, and 78% contributed all seven blood samples. Fifty-one participants (21.8%) reported clinical adverse events. An extremity syndrome, developing soon after the start of treatment, was the only event that occurred more frequently (P = 0.002) among the active groups (18.4 and 14.1% of the daily 125 and weekly 500 mg arms, respectively) compared with placebo (2.5%). The oltipraz arms did not differ in symptom type or severity, and there were no indications of exacerbated drug intolerance among the few participants infected with hepatitis B virus. The good compliance with an intense follow-up schedule shows that chemoprevention trials with biomarker end points may be conducted in such populations.

Linomide suppresses both Th1 and Th2 cytokines in experimental autoimmune myasthenia gravis

Suppressive effects of the synthetic immunomodulatory drug Linomide have been shown in several autoimmune models, including antibody-mediated experimental autoimmune myasthenia gravis (EAMG), a model for human myasthenia gravis (MG). To define the mechanisms underlying EAMG suppression, we injected Linomide subcutaneously at different doses into Lewis rats immunized with Torpedo acetylcholine receptor (AChR) in complete Freund's adjuvant (CFA), and investigated AChR-specific T and B cell responses, and the levels of lymph node cells expressing mRNA of different cytokines after AChR stimulation in vitro. Both 160 and 16, but not 1.6, mg/kg/day of Linomide effectively suppressed clinical muscle weakness, accompanied by decreased AChR-induced T and B cell responses. Linomide also suppressed the mRNA expression of the Th1 cytokines IFN-gamma, IL-12 and TNF-alpha as well as the Th2 cytokines IL-4 and IL-10, which are important in the immunopathogenesis of EAMG by promoting antibody production. There were no differences for IL-1beta, IL-6, lymphotoxin or TGF-beta expression in Linomide-treated vs nontreated control EAMG rats. We conclude that Linomide suppresses clinical EAMG as well as B and T cell responses to AChR by counteracting the production of AChR-induced Th1 and Th2 cytokines.

[POEMS syndrome--a report of eight cases and review of literature]

POEMS syndrome is an unusual multisystem disorder associated frequently with polyneuropathy, organomegaly, endocrinopathy, M-protein change and skin lesion. POEMS is the acronym the above-mentioned clinical manifestations. The patients who were diagnosed must have at least three of the manifestations; polyneuropathy and plasmagenic disorders are almost always present. We present in this paper eight patients, their clinical symptoms, laboratory tests and treatment were analysed and discussed.

[Effect of superoxide dismutase and diethyldithiocarbamate on the induction of squamous cell carcinoma of lung with methylcholanthrene in rats]

The squamous cell carcinoma of lung was induced with methylcholanthrene (MCA) in iodized oil in Wistar rats. During the development of the cancer, the animals were given superoxide dismutase (SOD) or its inhibitor diethyldithiocarbamate (DDC). In DDC group, 3 out of 50 rats developed cancer and 4 developed atypical hyperplasia of bronchial epithelium within 35 to 40 days. In SOD group, no cancer developed in all of the 52 rats, and only one had atypical hyperplasia in the lungs. Only one of 42 control rats had cancer and 2 rats had atypical hyperplasia of bronchial epithelium. The difference in cancer frequency between groups DDC and SOD was significant (P < 0.05). The results suggest that there is a synergism between DDC and MAC in the induction of lung cancer, while SOD can inhibit MCA-induced lung cancer development. The mechanism of the effect of SOD and DDC was discussed.

A preliminary observation on auto-cholinergic synapse dysfunction in patients with different types of epilepsy

Serum anti-acetylcholine receptor antibodies (A AchR Ab) and anti-synaptic premembrane antibodies (A PrM Ab) were measured in 21 patients with absence epilepsy, 21 cases with benign childhood epilepsy with centro-temporal spikes (BCECTs) and 13 cases with atypical epilepsy. Respectively, in five (23.8%), eleven (51.2%) and eight (66.7%) of the above mentioned groups of patients both A AchR Ab and A PrM Ab were found.

Thyroid or glucocorticoid hormone induces pre-growth-hormone mRNA and its probable nuclear precursor in rat pituitary cells

Thyroid or glucocorticoid hormone increases the synthesis of growth hormone (GH) by clonal lines of rat pituitary tumor cells. To investigate whether these increases arise from increased accumulation of GH-specific RNA sequences in the cytoplasm and nuclei of these cells, we adapted two existing procedures so that a 32P-labeled hybrid plasmid containing a cDNA sequence could be used to quantitate relative concentrations of the corresponding mRNA. One method (RNA gel blot hybridization) used electrophoresis of RNA, transfer to nitrocellulose paper, and hybridization to 32P-labeled plasmid. The other (RNA dot hybridization) used covalent attachment of RNA to activated cellulose paper squares and hybridization to 32P-labeled plasmid. As probe, we used a hybrid plasmid (pBR322-GH1) which we show by restriction analysis to contain a DNA sequence coding for rat GH. The results were comparable from both techniques and showed that incubation of GH3 cells with a thyroid hormone (triiodothyronine), a glucocorticoid hormone (dexamethasone), or both hormones caused an increase of cytoplasmic pre-GH mRNA sequences of about 4-, 22-, and 13-fold, respectively. Results obtained with the RNA gel blot hybridization method showed that hormonal stimulation leads to the induction of a single 1.0-kilobase species of pre-GH mRNA in the cytoplasm and of 2.7- and 1.0- kilobase species of GH-specific RNA in the nucleus.