Antibody persistence following preexposure regimens of cell-culture rabies vaccines: 10-year follow-up and proposal for a new booster policy

Subjects (n = 312) received either the human diploid cell rabies vaccine (HDCV) or the purified Vero cell rabies vaccine (PVRV) according to either two-injection (days 0 and 28) or three-injection (days 0, 7, and 28) primary regimens. They received a booster injection at 1 year. Rabies antibody levels were measured after the primary series and the booster and then each year for the next 10 years. The results confirm the superior long-term immunogenicity of the three-injection over the two-injection protocol. HDCV and PVRV in three doses were equally immunogenic. A booster injection at 1 year provides long-term seroconversion (titer > or = 0.5 IU/mL). Antibody titers 2 weeks after the 1-year booster allowed prediction of long-term immunity. Good responders, with titers > or = 30 IU/mL, were protected for at least 10 years. An algorithm for differentiation between good responders and poor responders with respect to vaccine booster strategies is proposed.

Comparison of two classification protocols in the evaluation of elbow dysplasia in the dog

The incidence of elbow disease based solely on arthrosis (ARTH) score was compared with a protocol using a combination of ARTH score plus a score for primary lesions (ED score). The population of dogs studied included 425 Bernese mountain dogs and 22 dogs of other breeds. The overall agreement between the two systems was high. However, 12 per cent of ARTH-score negative cases were positive using the ED score. This difference was statistically significant (P < 0.005). The female:male ratio of the dogs missed using the ARTH score was 2:1. The proportion of dogs affected with arthrosis increased with age, male dogs being affected more frequently. The development of arthrosis depends not only on age and breed, but probably also on gender. Thus, screening for elbow dysplasia should be based on at least two radiographic projections, including arthrosis and primary lesions. As the vast majority of dogs in this study were Bernese mountain dogs, conclusions are valid only for this breed.

G-protein betagamma-binding domains regulate insulin exocytosis in clonal pancreatic beta-cells

We have tested the putative role of G-protein beta-subunits in insulin exocytosis by transient expression of betagamma-binding proteins targeted to the plasma membrane. The PH domain of the G-protein-linked receptor kinase 2 fused to the transmembrane domain of a cell surface receptor and the alpha-subunit of the retinal G-protein transducin inhibited stimulated insulin release from intact and permeabilised HIT-T15 cells. This effect cannot be imputed to an increase in free Galpha, as the RGS protein RGS3 did not reverse this effect. Among the isoforms of Gbeta examined, Gbeta2 was detected on the plasma membrane by confocal immunomicroscopy. These observations suggest a role for G-protein betagamma-subunits in insulin exocytosis.

[Detection and sequence analysis of the p53 gene mutation in epithelial ovarian cancer]

OBJECTIVE

To find the characteristics of p53 gene mutation in epithelial ovarian cancer and to analyze the relationship between p53 mutation and FIGO stage.

METHODS

p53 mutations in exon 5 to 7 were detected by single-strand conformational polymorphism (SSCP) and sequencing technique.

RESULTS

8 of 46 tumor tissues demonstrated a SSCP band shift in the region of the gene. All of them have been characterized to represent DNA alterations by sequencing, including 8 point mutations (6 missence, 1 silent mutation and 1 in intron) and a 1-base pair insertion (introducing a stop codon downstream). Overall, 88.9% of mutation were transitions, and most of them are G-->A transitions (7/8, 87.5%). 62.5% of the mutation were found in 175 and 245 codon. The percentage of the mutation in stage I and stage II was 20.0%, and in stage III and stage IV was 16.7% (P > 0.05).

CONCLUSION

The arising of p53 mutations in ovarian cancer is due to spontaneous error in DNA synthesis and repair. Codon 175, 245 are the two mutational hot spots. There is no relationship between the mutation of p53 gene and FIGO stage in epithelial ovarian cancer.

Evaluation of the safety and immunogenicity of a new, heat-treated human rabies immune globulin using a sham, post-exposure prophylaxis of rabies

A double-blind, controlled, randomized trial was conducted to evaluate the safety and immunogenicity of a new human rabies immune globulin (HTRIG). This product, manufactured by Pasteur Merieux Connaught, PMC, has undergone a heat-treatment step (10 h at 60 degrees C) and removal of mercurothiolate. The corresponding unheated product available from the same manufacturer (human rabies immune globulin, HRIG, IMOGAM RABIES[spr2]) was used for comparison. These two rabies immune globulins (RIGs) were administered either alone or in association with the human diploid cell rabies vaccine (HDCV, IMOVAX[spr2] RABIES, PMC) according to a standard, post-exposure rabies prophylaxis schedule. Sixty-four healthy adults were randomly assigned to four groups of 16 to receive either HRIG/placebo, HTRIG/placebo, HRIG/HDCV or HTRIG/HDCV. RIG was administered at the recommended dose of 20 IU/kg by three intramuscular (i.m.) injections in the gluteus. HDCV or placebo was given on day (D) 0, D3, D7, D14, and D28 into the deltoid by the intramuscular (i.m.) route. Any local reaction from D0 to D3 at the immune globulin injection site, and any systemic reaction from D0 to D42, were monitored by subject diaries. Rabies-neutralizing serum antibody levels were assessed by the rapid fluorescent focus inhibition test (RFFIT) before treatment and on D3, D7, D14, D28, D35, and D42. No serious adverse reactions and, in particular, no allergic-type reactions were reported. The safety profiles of HTRIG and HRIG were similar, except that complaints of pain, or tenderness at the injection site were half as common in the HTRIG group. Most of the local reactions were mild or moderate. After the administration of HTRIG/placebo or HRIG/placebo, 60% of subjects had detectable rabies antibodies levels, but by D42 all titres were below the seroprotective level (i.e. below 0.5 IU/ml). In the groups HTRIG/HDCV and HRIG/HDCV, the antibody titres rose markedly from D7, and reached a maximum value of 19 IU/ml (95% CI, 11 to 38 IU/ml) and 31 IU/ml (95% CI, 20 to 48 IU/ml), respectively, on day 14. All subjects who received RIG and vaccine maintained a protective antibody level from D14 to D42. No significant difference in immunogenicity results between these two groups (HTRIG/HDCV and HRIG/HDCV) was observed, and no interference of immune globulin with vaccine was reported. The safety and immunogenicity profiles of PMC HTRIG appear comparable with the current reference product. The heat-treatment step will enhance the safety by further reducing the probability of virus transmission through immune globulin treatment. The low levels of rabies antibodies obtained by intramuscular administration of either PMC HTRIG or of PMC HRIG support the recommendations that call for local infiltration of wounds with RIG.

Ca2+-independent insulin exocytosis induced by alpha-latrotoxin requires latrophilin, a G protein-coupled receptor

alpha-Latrotoxin (alpha-LTX) induces exocytosis of small synaptic vesicles (SSVs) in neuronal cells both by a calcium-independent mechanism and by opening cation-permeable pores. Since the basic molecular events regulating exocytosis in neurons and endocrine cells may be similar, we have used the exocytosis of insulin-containing large dense core vesicles (LDCVs) as a model system. In primary pancreatic beta-cells and in the derived cell lines INS-1 and MIN6, alpha-LTX increased insulin release in the absence of extracellular calcium, but the insulin-secreting cell lines HIT-T15 and RINm5F were unresponsive. alpha-LTX did not alter membrane potential or cytosolic calcium, and its stimulatory effect on exocytosis was still observed in pre-permeabilized INS-1 cells kept at 0.1 microM Ca2+. Consequently, pore formation or ion fluxes induced by alpha-LTX could be excluded. The Ca2+-independent alpha-LTX-binding protein, latrophilin, is a novel member of the secretin family of G protein-coupled receptors (GPCR). Sensitivity to alpha-LTX correlated with expression of latrophilin, but not with synaptotagmin I or neurexin Ialpha expression. Moreover, transient expression of latrophilin in HIT-T15 cells conferred alpha-LTX-induced exocytosis. Our results indicate that direct stimulation of exocytosis by a GPCR mediates the Ca2+-independent effects of alpha-LTX in the absence of altered ion fluxes. Therefore, direct regulation by receptor-activated heterotrimeric G proteins constitutes an important feature of the endocrine exocytosis of insulin-containing LDCVs and may also apply to SSV exocytosis in neurons.

Preclinical assessment of immunoreactivity of a new purified equine F(ab')2 against European viper venom

The immunological and pharmacokinetic properties of a new, further purified, pasteurized preparation of equine F(ab')2 (VIPERFAV) against Vipera aspis, Vipera berus, and Vipera ammodytes venom were compared with the current equine F(ab')2 preparation (IPSER Europe). Affinity constants of the V. aspis-specific F(ab')2 were determined using biosensor technology and found to be in the range of 10(8) M-1 for the four antigenic fractions of V. aspis toxins and for both F(ab')2 preparations. The improvement of 51% in the specific activity (LD50 mg-1) of the new F(ab')2 was in close agreement with the 1.8-fold increase in the immunoreactive fraction of the new preparation. In vivo investigations of venom immunocomplexation by F(ab')2 in rabbits confirmed the ability of F(ab')2 to neutralize and redistribute toxin venom. Infusion of a stoichiometric molar ratio (i.e., 1 mg kg-1) of the new antivenom induced a 2.3-fold elevation of the plasma venom concentration with a Tmax observed 8 h after F(ab')2 administration and a decline in the terminal half-life from 31.92 +/- 4.49 h to 16.73 +/- 4.34 h, in contrast, for the venom alone. The area under the curve was 1.4-fold greater in the VIPERFAV group than in the IPSER Europe group during the post-F(ab')2 infusion period. Increasing the F(ab')2 dose to 3 mg kg-1 increased by 27% the percent of venom bound to F(ab')2. Finally, the greater the venom distribution, the smaller and less pronounced the plasma redistribution. These results demonstrate that the purification and pasteurization steps involved in the preparation of the new F(ab')2 have no deleterious influence on F(ab')2 affinity but, on the contrary, improve the protective efficacy. Alteration of viper venom kinetics by specific F(ab')2 antivenom was also shown to be dependent on the interval between of F(ab')2 administration and venom bite and on the specific F(ab')2 dose administered.

[Secondary infection of the ovarian endometriotic cysts]

OBJECTIVE

To explore the clinic manifestations, diagnostic methods and principles of management in the secondary infection of the endometriotic cysts of ovary.

METHODS

Thirteen cases of the infected ovarian endometriotic cysts were analysed retrospectively in our hospital from Jan. 1990 to Dec. 1996. The diagnosis was confirmed by the operation and pathologic findings.

RESULTS

The clinic manifestations were divided into five types, namely acute, subacute, chronic, occult and stabile types. The definitive diagnosis can be made by abdominal pain, fever and adnexal mass combined with B-scan findings and chocolate-brown purulent fluid which was punctured from the adnexal mass. Operation was the main method for treatment.

CONCLUSIONS

Secondary infection of the endometriotic cyst is one of the gynecologic emergency. Correct diagnosis and prompt management are of vital importance.

Evaluation of the safety and pharmacokinetic profile of a new, pasteurized, human tetanus immunoglobulin administered as sham, postexposure prophylaxis of tetanus

In a monocentric, double-blind, randomized trial, we examined the safety and pharmacokinetic profile of a new, pasteurized, human tetanus immunoglobulin (P-HTIG). As part of the purification process, P-HTIG has undergone a heat treatment step (10 h at 60 degrees C) and the removal of Merthiolate. Forty-eight adults with a history of tetanus vaccination were randomized into four groups (n = 12 per group) to receive one of two different batches of this P-HTIG simultaneously with either tetanus-diphtheria (Td) vaccine (sham, postexposure prophylaxis of tetanus) or placebo. Local reactions at the injection site were followed for the first 3 days after injection, and systemic reactions were followed during the entire study period, i.e., up to 42 days posttreatment. Blood samples for tetanus antibody titer determination (enzyme-linked immunosorbent assay method) were drawn prior to treatment on day 0 and on days 1, 2, 3, 7, 14, 21, 28, 35, and 42. A normalization of tetanus antibody titers (subtraction of the day 0 value for each subject at each time period) was performed to assess the additive effect of P-HTIG on tetanus antibody titers. The pharmacokinetic parameters were determined by both a compartmental analysis (modelization) and a noncompartmental analysis. No severe adverse reactions were reported. The rate of local reactions at the P-HTIG injection site was 27%. All local reactions were mild and resolved within 2 days. In contrast, local reactions at the vaccine injection site were seen in 79% of the subjects. The rate of systemic reactions was similar in the P-HTIG plus Td vaccine group (33%) and in the P-HTIG plus placebo group (21%), and all these reactions were mild. In the P-HTIG plus placebo group, tetanus antibody titers rose to a maximum of 0.313+/-2.49 IU/ml after 4.4 days; in the P-HTIG plus Td vaccine group, a maximum concentration of 15.2+/-2.42 IU/ml was reached 19 days postinjection. In both groups, 100% of the patients had seroprotective levels of tetanus antibodies (> or = 0.01 IU/ml) 2 days following treatment. An anamnestic response to Td vaccine appeared 7 days postimmunization. In conclusion, P-HTIG has a good safety and pharmacokinetic profile. Our results confirm that immunoglobulin should be associated with vaccine in the treatment of tetanus-prone wounds.

A new technique of dural closure--experience with a vicryl mesh

Treatment of postoperative dural CSF leaks following posterior fossa surgery remains a difficult and often perplexing problem. Their management includes either non-operative management or surgical re-exploration. In order to avoid CSF leaks we developed a simple but effective method using a well-cut sheet of a vicryl-poly-p-dioxanone mesh (Ethisorb) covering the whole defect of the craniectomy. This paper presents our technique of dural closure, experiences with and advantages of the vicryl mesh in comparison with conventional procedures using muscle patches in combination with fibrin sealant or fibrin glue alone. Attention is focused upon the frequency of postoperative complications, in particular infection rate and CSF leaks. Furthermore, histomorphological observations after implantation of a vicryl mesh are demonstrated. In conclusion, due to its specific qualities we consider the vicryl mesh as a suitable dural substitute with potential advantages over currently used material.

Encapsulation of Inorganic Particles by Dispersion Polymerization in Polar Media

Polymer encapsulation of small silica particles, using dispersion polymerization of styrene in aqueous ethanol medium with poly(N-vinyl pyrrolidone) (PVP) as stabilizer, is described. Silica particles, directly synthesized by the Stober process in an aqueous ethanol medium, are either unreacted (hydrophilic character) or coated with 3-(trimethoxysilyl)propyl methacrylate (MPS) (hydrophobic character), which is grafted at the silica particle surface. When the bare silica particles are used as the seed, there is a strong tendency of the silica beads to cover the surface of the polystyrene particles and obviously encapsulation does not occur. On the contrary, when the silica surface is made hydrophobic by coating, the inorganic particles are entirely contained in the polystyrene particles as evidenced by microscopy techniques (TEM, SEM, AFM). It is shown that some polystyrene chains are then chemically bonded to the silica particles, through the coupling agent MPS, and that only a small amount of bonded polystyrene, compared to the total polystyrene synthesized, is sufficient to obtain encapsulation of the silica particles with the entire amount of polystyrene synthesized during the polymerization. Under our experimental conditions, each polystyrene latex particle contains, on average, 4 to 23 silica beads depending, in particular, on the size of the silica. We believe that it is possible to control the composite particle size and morphology by a convenient choice of the composition of the system. Moreover, this new polymer-encapsulation process could be used to synthesize other organic-inorganic composite particles, using, for example, other monomers or minerals. Copyright 1998 Academic Press. Copyright 1998Academic Press

Suppressant effect of human or equine rabies immunoglobulins on the immunogenicity of post-exposure rabies vaccination under the 2-1-1 regimen: a field trial in Indonesia. MAS054 Clinical Investigator Group

WHO's reference protocol for post-exposure rabies vaccination advises five intramuscular injections on days 0, 3, 7, 14, and 30; in addition, rabies immunoglobulins (RIG) must be given to serious cases of exposure (grade III severity). Some studies indicate that these immunoglobulins suppress the immunogenicity of rabies vaccine when administered according to an alternative protocol of four injections (2-1-1) on days 0, 7, and 21, which was therefore not recommended for grade III exposures. To test this effect, we conducted a multicentre study in Indonesia using three groups of subjects. One group received only the Vero-cell rabies vaccine (PVRV, Verorab, usual commercial lot) according to the 2-1-1 schedule. The second and third groups received the same schedule of PVRV, plus either equine rabies immunoglobulins (ERIG, 40 IU/kg body weight) or human rabies immunoglobulins (HRIG, 20 IU/kg body weight). Our results confirmed the immunoglobulin suppressant effect, which was more pronounced with human than equine immunoglobulins. In both groups receiving immunoglobulins, the seroconversion rates did not reach 100% on day 28 and the geometric mean antibody titre was lower. Thus, WHO's recommendation in 1992 of the reference protocol plus immunoglobulins for severe cases is substantiated by these results in Indonesian subjects. If the 2-1-1 regimen is chosen by the treating physician and immunoglobulins are indicated, preference should be given to purified equine RIG, which also costs less than human RIG.

Ultrasonographic detection of adrenal gland tumor and ureterolithiasis in a guinea pig

A 5-year-old guinea pig was presented to the University of Berne Small Animal Radiology Department for an ultrasound examination of the abdomen to confirm a suspected diagnosis of Cushing's syndrome. The patient had bilateral alopecia, was apathic and obese. Ultrasonographically, a tumor of the left adrenal gland, obstruction of the left ureter by an ureterolith, as well as hydronephrosis of the left kidney were detected. During surgery to relieve the ureteral obstruction the adrenal gland tumor was removed. The guinea pig died post-operatively due to blood loss. The left adrenal gland tumor was found histopathologically to be an adenoma and the right adrenal gland also had multiple small adenomas, but grossly appeared normal. The ureterolith was analyzed and found by x-ray diffraction to consist of calcium carbonate.

Enforced Bcl-2 expression inhibits antigen-mediated clonal elimination of peripheral B cells in an antigen dose-dependent manner and promotes receptor editing in autoreactive, immature B cells

The mechanisms that establish immune tolerance in immature and mature B cells appear to be distinct. Membrane-bound autoantigen is thought to induce developmental arrest and receptor editing in immature B cells, whereas mature B cells have shortened lifespans when exposed to the same stimulus. In this study, we used Emu-bcl-2-22 transgenic (Tg) mice to test the prediction that enforced expression of the Bcl-2 apoptotic inhibitor in B cells would rescue mature, but not immature, B cells from tolerance induction. To monitor tolerance to the natural membrane autoantigen H-2Kb, we bred 3-83mudelta (anti-Kk,b) Ig Tg mice to H-2(b) mice or to mice expressing transgene-driven Kb in the periphery. In 3-83mudelta/bcl-2 Tg mice, deletion of autoreactive B cells induced by peripheral Kb antigen expression in the liver (MT-Kb Tg) or epithelia (KerIV-Kb Tg), was partly or completely inhibited, respectively. Furthermore, Bcl-2 protected peritoneal B-2 B cells from deletion mediated by acute antigen exposure, but this protection could be overcome by higher antigen dose. In contrast to its ability to block peripheral self-tolerance, Bcl-2 overexpression failed to inhibit central tolerance induced by bone marrow antigen expression, but instead, enhanced the receptor editing process. These studies indicate that apoptosis plays distinct roles in central and peripheral B cell tolerance.

The first C2 domain of synaptotagmin is required for exocytosis of insulin from pancreatic beta-cells: action of synaptotagmin at low micromolar calcium

The Ca2+- and phospholipid-binding protein synaptotagmin is involved in neuroexocytosis. Its precise role and Ca2+-affinity in vivo are unclear. We investigated its putative function in insulin secretion which is maximally stimulated by 10 microM cytosolic free Ca2+. The well-characterized synaptotagmin isoforms I and II are present in pancreatic beta-cell lines RINm5F, INS-1 and HIT-T15 as shown by Northern and Western blots. Subcellular fractionation and confocal microscopy revealed their presence mainly on insulin-containing secretory granules whereas only minor amounts were found on synaptic vesicle-like microvesicles. Antibodies or Fab-fragments directed against the Ca2+-dependent phospholipid binding site of the first C2 domain of synaptotagmin I or II inhibited Ca2+-stimulated, but not GTPgammaS-induced exocytosis from streptolysin-O-permeabilized INS-1 and HIT-T15 cells. Transient expression of wild-type synaptotagmin II did not alter exocytosis in HIT-T15 cells. However, mutations in the Ca2+-dependent phospholipid binding site of the first C2 domain (Delta180-183, D231S) again inhibited only Ca2+-, but not GTPgammaS-evoked exocytosis. In contrast, mutations in the IP4-binding sites of the second C2 domain (Delta325-341; K327,328, 332Q) did not alter exocytosis. Synaptotagmin II mutated in both C2 domains (Delta180-183/K327,328,332Q) induced greater inhibition than mutant Delta180-183, suggesting a discrete requirement for the second C2 domain. Thus, synaptotagmin isoforms regulate exocytotic events occurring at low micromolar Ca2+.

[The relationship between multi-drug resistance gene expression and drug resistance of ovarian carcinoma]

OBJECTIVE

To study the relationship between multi-drug-resistance (MDR1) gene expression and the drug resistance of ovarian carcinoma and the reversing potency of drug-resistance modifying agent--cyclosporin A (CsA).

METHODS

Tumor-bearing mice of ovarian carcinoma cell (OVCA3) were divided randomly into three groups: control group, adriamycin (ADM) group and ADM +CsA group. The tumor growth rate and the survival rate of mice were investigated and compared among the groups. 32 frozen specimens of ovarian carcinoma tissue from patients were examined for the expression of MDR1 gene by means of RT-PCR.

RESULT

Ovarian carcinoma cells with positive MDR1 gene expression showed cross drug-resistance to ADM, daunorubicin (DNR), vincristine (VCR) and etoposide (VP-16), the value of inhibiting concentration (IC50) is 4.1-15.5 times of that of the cells with negative MDR1 gene expression. To tumor-bearing mice, there was significant difference in tumor growth rate between mice given combined therapy of CsA + ADM and those given ADM only (P<0.01) Of the 32 frozen specimens of ovarian carcinoma tissue, there was no confirmed relationship between MDR1 gene expression and the pathologic type or differential grade. The possibility of poor prognosis of patients with positive MDR1, gene expression was 16.07 (1.78-144.7) times of that of patients with negative MDR1 gene expression.

CONCLUSION

MDR-related drug can induce the overexpression of MDR1 gene and result in the appearance of the multidrug resistance phenomenon. CsA can partially reverse the multidrug resistance of ovarian carcinoma cells both in vitro and in vivo. Detection of MDR1 gene expression in patients of ovarian carcinoma could be used as an index to predict the prognosis of the patients.