[Inhibitory effects of recombinant human neurotrophin-4/5 protein on neurotoxicity caused by arsenic trioxide]

OBJECTIVE

To study preliminarily the inhibitory effects of recombinant human neurotrophin (hNT)-4/5 protein on neurotoxicity caused by arsenic trioxide (As(2)O(3)).

METHODS

Nerve cells of the chicken embryonic forebrain and PC12 cells were co-cultured with recombinant hNT-4/5 protein and As(2)O(3) (0 - 16 micromol/L) for 24 and 48 hours, respectively, to observe the survival of nerve cells and the outgrowth of PC12 cells, with clone expression and recombination techniques.

RESULTS

There was significant difference in survival rate of nerve cells between the experimental and control groups (P < 0.01) after co-culture for 48 hours, and survival rate and number of neuron outgrowth increased with the concentration of hNT-4/5 protein.

CONCLUSION

Recombinant hNT-4/5 protein could inhibit neurotoxicity caused by As(2)O(3), which provided a basis to find an anti-toxic factor in the environment by genetic engineering.

Abacavir: absolute bioavailability, bioequivalence of three oral formulations, and effect of food

STUDY OBJECTIVES

Study A: to determine the absolute bioavailability of a single 300-mg abacavir hemisulfate tablet. Study B: to determine the bioequivalence of two oral abacavir formulations (300-mg hemisulfate tablet, 100-mg succinate caplet), the effect of food on the bioavailability of the 300-mg hemisulfate tablet, and the bioavailability of the hemisulfate tablet relative to the hemisulfate solution.

DESIGN

Phase I, randomized, open-label, balanced two- (study A) and three- or four-period (study B), crossover studies.

SETTING

Two clinical research centers.

SUBJECTS

Six men infected with the human immunodeficiency virus (HIV), aged 27-39 years (study A), and 18 HIV-infected men and women, aged 21-50 years (study B).

INTERVENTIONS

In study A, all subjects received a single, oral 300-mg tablet of abacavir hemisulfate or a single, intravenous infusion of abacavir hemisulfate 150 mg over 60 minutes. In study B, all subjects received each of three single-dose treatments: three 100-mg abacavir succinate caplets in a fasted state, one 300-mg abacavir hemisulfate tablet in a fasted state, and one 300-mg abacavir hemisulfate tablet with a high-fat breakfast. Twelve subjects in study B also received a fourth treatment of abacavir hemisulfate 300 mg as an oral solution in a fasted state. Plasma samples collected for 24 hours (study A) or 12 hours (study B), and urine samples collected for 12 hours (study A) were analyzed by validated high-performance liquid chromatographic methods.

MEASUREMENTS AND MAIN RESULTS

Abacavir pharmacokinetic parameters were calculated using standard, noncompartmental methods. In study A, the geometric least square (GLS) mean absolute bioavailability of oral abacavir was 83% (range 65-107%). In study B, the hemisulfate tablet was bioequivalent to the succinate caplet, but its time to maximum concentration (Tmax) occurred 30 minutes earlier. Administration of the abacavir hemisulfate tablet with food had no effect on area under the curve from time zero to infinity (AUC0-infinity), decreased maximum concentration (Cmax) by 26%, and delayed Tmax by 38 minutes. The relative bioavailability (GLS mean AUC0-infinity ratio) of the 300-mg abacavir hemisulfate tablet to solution was 101%, Cmax was 11% lower, and Tmax was unchanged. The most common drug-related adverse events associated with abacavir were nausea, vomiting, abdominal pain, and headache, all of which were mild.

CONCLUSION

Based on our results, abacavir is safe and well tolerated and can be administered with or without meals.

[The free searchable patent databases on Internet]

The names and the addresses of the free searchable patent databases on Internet were provided in this paper. The basic ways of information search methods were also introduced.

Inhibitory effect of green and black tea on tumor growth

The administration of green tea, black tea, or (-)-epigallocatechin gallate inhibited the growth of established nonmalignant and malignant tumors in tumor-bearing mice. In experiments with black tea, we found that its oral administration inhibited DNA synthesis and enhanced apoptosis in both nonmalignant and malignant tumors in tumor-bearing mice.

Safety and pharmacokinetics of abacavir (1592U89) following oral administration of escalating single doses in human immunodeficiency virus type 1-infected adults

Abacavir (1592U89) is a nucleoside analog reverse transcriptase inhibitor that has been demonstrated to have selective activity against human immunodeficiency virus (HIV) in vitro and favorable safety profiles in mice and monkeys. A phase I study was conducted to evaluate the safety and pharmacokinetics of abacavir following oral administration of single escalating doses (100, 300, 600, 900, and 1,200 mg) to HIV-infected adults. In this double-blind, placebo-controlled study, subjects with baseline CD4+ cell counts ranging from < 50 to 713 cells per mm3 (median, 315 cells per mm3) were randomly assigned to receive abacavir (n = 12) or placebo (n = 6). The bioavailability of the caplet formulation relative to that of the oral solution was also assessed with the 300-mg dose. Abacavir was well tolerated by all subjects; mild to moderate asthenia, abdominal pain, headache, diarrhea, and dyspepsia were the most frequently reported adverse events, and these were not dose related. No significant clinical or laboratory abnormalities were observed throughout the study. All doses resulted in mean abacavir concentrations in plasma that exceeded the mean 50% inhibitory concentration (IC50) for clinical HIV isolates in vitro (0.07 microgram/ml) for almost 3 h. Abacavir was rapidly absorbed following oral administration, with the time to the peak concentration in plasma occurring at 1.0 to 1.7 h postdosing. Mean maximum concentrations in plasma (Cmax) and the area under the plasma concentration-time curve from time zero to infinity (AUC0-infinity) increased slightly more than proportionally from 100 to 600 mg (from 0.6 to 4.7 micrograms/ml for Cmax; from 1.0 to 15.7 micrograms.h/ml for AUC0-infinity) but increased proportionally from 600 to 1,200 mg (from 4.7 to 9.6 micrograms/ml for Cmax; from 15.7 to 32.8 micrograms.h/ml for AUC0-infinity. The elimination of abacavir from plasma was rapid, with an apparent elimination half-life of 0.9 to 1.7 h. Abacavir was well absorbed, with a relative bioavailability of the caplet formulation of 96% versus that of an oral solution (drug substance in water). In conclusion, this study showed that abacavir is safe and is well tolerated by HIV-infected subjects and demonstrated predictable pharmacokinetic characteristics when it was administered as single oral doses ranging from 100 to 1,200 mg.

Safety and single-dose pharmacokinetics of abacavir (1592U89) in human immunodeficiency virus type 1-infected children

Abacavir (formerly 1592U89) is a potent 2'-deoxyguanosine analog reverse transcriptase inhibitor that has been demonstrated to have a favorable safety profile in initial clinical trials with adults with human immunodeficiency virus (HIV) type 1 infection. A phase I study was conducted to evaluate the pharmacokinetics and safety of abacavir following the administration of two single oral doses (4 and 8 mg/kg of body weight) to 22 HIV-infected children ages 3 months to 13 years. Plasma was collected for analysis at predose and at 0.5, 1, 1.5, 2, 2.5, 3, 5, and 8 h after the administration of each dose. Plasma abacavir concentrations were determined by high-performance liquid chromatography, and data were analyzed by noncompartmental methods. Abacavir was well tolerated by all subjects. The single abacavir-related adverse event was rash, which occurred in 2 of 22 subjects. After administration of the oral solution, abacavir was rapidly absorbed, with the time to the peak concentration in plasma occurring within 1.5 h postdosing. Pharmacokinetic parameter estimates were comparable among the different age groups for each dose level. The mean maximum concentration in plasma (Cmax) and the mean area under the curve from time zero to infinity (AUC0-infinity) increased by 16 and 45% more than predicted, respectively, as the abacavir dose was doubled from 4 to 8 mg/kg (Cmax increased from 1.69 to 3.94 micrograms/ml, and AUC0-infinity increased from 2.82 to 8.09 micrograms.h/ml). Abacavir was rapidly eliminated, with a mean elimination half-life of 0.98 to 1.13 h. The mean apparent clearance from plasma decreased from 27.35 to 18.88 ml/min/kg as the dose increased. Neither body surface area nor creatinine clearance were correlated with pharmacokinetic estimates at either dose. The extent of exposure to abacavir appears to be slightly lower in children than in adults, with the comparable unit doses being based on body weight. In conclusion, this study showed that abacavir is safe and well tolerated in children when it is administered as a single oral dose of 4 or 8 mg/kg.

[An experimental study of anti-angiogenesis with a cartilage-derived inhibitor]

OBJECTIVE

To evaluate the efficacy of a cartilage-derived inhibitor for the treatment of corneal neovascularization in vivo.

METHODS

A cartilage-derived inhibitor (CDI) from bovine scapula was purified to homogeneity. By rabbit corneal neovascularization (CNV) model, the effect of inhibition of CDI under various conditions was determined in corneal micropocket analysis.

RESULTS

The purified CDI could inhibit strongly the growing speed and area of rabbit CNV compared to control (P < 0.001).

CONCLUSION

It is demonstrated that CDI is a potent dose-dependent inhibitor of angiogenesis.

[Determination of adenosine in Rehmannia glutinosa Libosch. by HPLC]

OBJECTIVE

To establish a method to determine the contents of asenosine in different species of Rehmannia glutinosa.

METHOD

The contents were determined by HPLC, with a column of KYWG-C18 as stationary phase, 6% ace tonitrile as mobile phase and detecting wavelength at 260 nm.

RESULT

Adenosine has a good linearity in the range of 0.002 mg/ml-0.01 mg/ml, Y = 1.7742 x 10(-4) + 8.9021 x 10(-7) X, r = 0.9995. The average recovery is 94.1% and RSD = 1.86% (n = 5).

CONCLUSION

The method is fast, reliable and simple.

[Effects of different thyroid status on the pharmacokinetics of diazepam]

Experimental models of hypothyroidism and hyperthyroidism in Sprague-Dawley rats were established in this study. Diazepam was given to rats at a single oral dose of 30-40 mg.kg-1 and the plasma concentration of diazepam was detected by HPLC. The results showed that the plasma concentration of diazepam was significantly higher in hypothyroid rats than that in controls (P < 0.05). The Cmax, AUC and T1/2 (Ka) were increased. The Vd was decreased and the elimination was slowed. Mild hyperthyroidism showed nearly no effect on the plasma concentration, Cmax and AUC of diazepam in the rats. But when the rats became more heavily hyperthyroid, the plasma concentration, Cmax and AUC of diazepam were increased gradually. The absorption of diazepam was changed slightly in mild and moderate hyperthyroid rats, the Vd was decreased and the elimination was accelerated. In heavily hyperthyroid rats, however, the absorption of diazepam was obviously accelerated. The Vd was decreased and the elimination was slowed. Therefore, we conclude that different thyroid status may have different effects on the pharmacokinetics of diazepam.

Insulin receptor exon 11+/- isoform mRNA in spontaneously hypertensive and adrenocorticotropin-hypertensive rats

OBJECTIVE

To test the hypothesis that insulin resistance of the spontaneously hypertensive rat (SHR) and adrenocorticotropin-hypertensive rat is related to a difference in the proportion of the functionally different, alternatively spliced exon 11 isoforms of the insulin receptor.

DESIGN

We determined the proportions of mRNA for the exon 11+ and exon 11- isoforms in various tissues of SHR and Wistar-Kyoto rats aged 3, 6, 9 and 12 weeks, which span the pre-hypertensive phase through to established hypertension, as well as in Sprague-Dawley rats with adrenocorticotropin-induced hypertension and Sprague-Dawley controls.

METHODS

Detection of mRNA involved a reverse-transcriptase polymerase chain reaction technique specific for each isoform and quantification was by slot and dot blot hybridization.

RESULTS

Mean proportions of exon 11+ mRNA in SHR, Wistar-Kyoto rats, adrenocorticotropin-hypertensive rats and Sprague-Dawley control rats at each age were 95% for liver, 82% for adipose tissue, 77% for kidney, 66% for adrenal, 53% for heart, 26% for cerebral cortex, 23% for hypothalamus, and 3% for skeletal muscle. There was also no difference in concentration of total insulin receptor mRNA.

CONCLUSIONS

The absence of any difference in proportions of insulin receptor mRNA isoforms argues against the hypothesis that an alteration of differential splicing plays a role in the models of hypertension studied.

[Pharmacokinetic profile of naftopidil in rats]

Naftopidil(Naf), a novel antihypertensive drug, was determined by HPLC-UV method. The plasma concentration and pharmacokinetics of naftopidil have been investigated in rats after single oral doses of 10, 20 and 30 mg.kg-1. The drug was found to conform to a two-compartment model. Tp was in the range of 0.42 h to 0.90 h. T1/2 beta was 7.08 h after the 10 mg.kg-1 dose, 4.78 h after the 20 mg.kg-1 dose and 5.83 h after the 30 mg.kg-1 dose. The Cmax, AUC and CL/F appeared to be dose dependent at the doses not higher than 20 mg.kg-1. Naf was found in many tissues after a single oral dose of 20 mg.kg-1. The top level tissues were intestine, liver and lung at 15 minutes after administration, while the utero-ovarian tissue was the highest at 6 h. Naf can be extensively metabolized since the total excretion of the parent compound in urine and faeces was less than 1% of the dose. From 82% to 97% of Naf in plasma was shown to be bound to protein.

[A study on diagnosis of ocular adnexal lymphoid hyperplasia by polymerase chain reaction amplified IgH CDR-III sequence]

OBJECTIVE

To study the diagnosis and classification of ocular adnexal lymphoid hyperplasia and investigate its cell origin by using some molecular biological techniques.

METHODS

29 cases (31 eyes) of ocular adnexal lymphoid hyperplasia were examined for immunoglobulin heavy-chain (IgH) gene rearrangements by means of polymerase chain reaction (PCR) to amplify the complementarity determining region III (CDR-III) with formalin-fixed and paraffin-embedded tissue combining with histopathologic examination and immunophenotypic analysis.

RESULTS

17 eyes of malignant lymphoma and 5 eyes of reactive lymphoid hyperplasia demonstrated clear single band of the rearranged gene for the IgH chain between 100 bp. to 120 bp. The bilateral ocular adnexal lymphoma occurring simultaneously in 4 eyes (two individuals) exhibited identical band. 1 eye of malignant lymphoma, 8 eyes of atypical lymphoid hyperplasias and 6 eyes of reactive lymphoid hyperplasia showed no band or a smear band.

CONCLUSIONS

The results show that this method can determine the clonality of the lymphoid hyperplasias. It may be as well in the examination of small monoclonal B cell populations for which immunophenotypical analysis is difficult. The method is an objective, accurate and useful approach for the diagnosis of ocular adnexal lymphoid hyperplasias.

Effect of hypoxia on the proliferation of retinal microvessel endothelial cells in culture

BACKGROUND

To determine if hypoxia stimulates the proliferation of retinal microvessel endothelial cells in culture.

METHODS

Bovine retinal microvessel endothelial cells were cultured in normoxic (95% air, 5% CO2) and hypoxic (2% O2, 5% CO2, 93% N2) conditions. Endothelial cells were identified by acetylated LDL and Factor VIII-related antigen immunocytochemical staining. Cells from passages three to eight were used in these experiments. Proliferation assays included cell counts by hemocytometer and autoradiographic analysis of incorporated 3H-thymidine (3H-TdR).

RESULTS

At day 4, cell counts of endothelial cells in hypoxia showed a 133% increase over those grown in normoxic conditions (N = 25, P < 0.01). Cell counts per day for 5 days were 121-181% greater in hypoxia. Autoradiography of endothelial cells exposed to 3H-TdR and counted every 12 hours for 60 hours exhibited labeling indices 112-118% higher in hypoxic conditions (P < 0.0001). Endothelial cells cultured under hypoxic conditions were smaller and spindle-shaped, whereas those grown under normoxic conditions were larger and more polygonal.

CONCLUSIONS

Hypoxia increases DNA synthesis and stimulates proliferation of retinal microvessel endothelial cells in vitro and induces alterations in morphology. These results may be relevant to microvessel angiogenesis, which occurs in vivo under ischemic conditions.

[A study on the loss of heterozygosity at 17p13.3 and abnormal expression of p53 protein in gastric carcinoma]

OBJECTIVE

To evaluate the role of 17p13.3 loss and abnormal expression of p53 in the development and progress of gastric carcinoma.

METHODS

The loss of heterozygosity (LOH) at 17p13.3 and abnormal expression of p53 gene were examined with PCR-RFLP and immunohistochemical methods in 51 surgical specimens of gastric carcinoma.

RESULTS

LOH at 17p13.3 was detected in 16/31 cases (51.6%) and positive staining for p53 protein was found in 19/51 cases (37.3%). No significant correlation was found between LOH at 17p13.3 and abnormal expression of p53 or between these two events in any clinicopathological parameters. LOH was found in one cases of early gastric cancer.

CONCLUSIONS

These results suggest that LOH at 17p and abnormal expression of p53 protein are frequently found in gastric carcinoma and may play an important role in the carcinogenesis and progress of both intestinal and gastric types of gastric cancer.

Adaptation to sublethal environmental stresses protects Listeria monocytogenes against lethal preservation factors

A sublethal dose of ethanol (5%, vol/vol), acid (HCl, pH 4.5 to 5.0), H2O2 (500 ppm), or NaCl (7%, wt/vol) was added to a Listeria monocytogenes culture at the exponential phase, and the cells were allowed to grow for 1 h. Exponential-phase cells also were heat shocked at 45 degrees C for 1 h. The stress-adapted cells were then subjected to the following factors at the indicated lethal levels--NaCl (25%, wt/vol), ethanol (17.5%, vol/vol), hydrogen peroxide (0.1%, wt/vol), acid (pH 3.5), and starvation on 0.1 M phosphate buffer at pH 7.0 (up to 300 h). Viable counts of the pathogen, after the treatment, were determined on Trypticase soy agar-yeast extract, and survivor plots were constructed. The area (h.log10 CFU/ml) between the control and treatment curves was calculated to represent the protective effect resulting from adaptation to the sublethal stress factor. Adaptation to pH 4.5 to 5.0 or 5% ethanol significantly (P < 0.05) increased the resistance of L. monocytogenes to lethal doses of acid, ethanol, and H2O2. Adaptation to ethanol significantly (P < 0.05) increased the resistance to 25% NaCl. When L. monocytogenes was adapted to 500 ppm of H2O2, 7% NaCl, or heat, resistance of the pathogen to 1% hydrogen peroxide increased significantly (P < 0.05). Heat shock significantly (P < 0.05) increased the resistance to ethanol and NaCl. Therefore, the occurrence of stress protection after adaptation of L. monocytogenes to environmental stresses depends on the type of stress encountered and the lethal factor applied. This "stress hardening" should be considered when current food processing technologies are modified or new ones are developed.

Breed differences in boar taint: relationship between tissue levels boar taint compounds and sensory analysis of taint

A total of 228 intact male pigs form Duroc, Hampshire, Landrace, and Yorkshire breeds were used in the experiment. Samples of salivary gland and backfat were collected at slaughter for colorimetric assay of salivary and fat 16-androstene levels and fat skatole levels. Fat levels also were tested by a sensory panel using an R-index technique for detecting the presence of boar taint. The proportion of tainted carcasses determined by the sensory panel was 5.0% for androstenone and 11.4% for skatole, with a combined total of 15.0% tainted from either source. Sensory analysis of taint showed a lower proportion (P < .05) of tainted carcasses in Hampshire, with no difference in taint across the other three breeds. Analysis of taint compounds indicated that overall 14.5% of pigs had salivary gland 16-androstene levels and 20.9% had fat 16-androstene levels above acceptable limits. There was a higher (P < .05) proportion of Duroc pigs above the threshold levels for 16-androstenes in both salivary gland and fat. Landrace pigs had the lowest (P < .05) average tissue concentrations of steroids and skatole. Across breeds, only 1.8% of pigs had fat skatole concentrations above .25 ppm, which has been suggested as threshold levels of skatole for taint. The canonical correlation coefficient between fat compound levels and the R-indices of fat 16-androstenes and skatole was .40 (P < .001). Our results indicate breed differences in tissue levels of taint compounds and in taint assessed by a sensory panel. Levels of 16-androstene steroids were highly associated with taint, but more pigs had measured levels above the threshold than those identified as tainted by sensory analysis. Levels of fat skatole were low overall and did not account for all the pigs judged as tainted from skatole by sensory analysis.

Overall and cause-specific mortality in a cohort of homo-/bisexual men, injecting drug users, and female partners of HIV-infected men. Pulmonary Complications of Human Immunodeficiency Virus Infection Study Group

OBJECTIVE

To study the overall and cause-specific HIV-related mortality in a cohort of HIV-seropositive subjects according to transmission category, race/ethnicity, sex and severity of immunosuppression.

DESIGN

A cohort of 1129 HIV-seropositive homo-/bisexual men, injecting drug users, and female partners of HIV-infected men were enrolled at six centers in San Francisco, Los Angeles, Chicago, Newark, Detroit and New York between 1 November 1988 and 1 November 1989. Subjects were evaluated every 6 months at least until 31 March 1994.

METHODS

The analyses of overall mortality for the subgroups of interest were performed with Kaplan-Meier plots and Cox proportional hazards models. Cause-specific analyses were performed on the primary cause of death using rates per 100 person-years of exposure.

RESULTS AND CONCLUSIONS

Baseline severity of immunosuppression is the strongest predictor of mortality. There were no statistically significant differences in overall HIV-related mortality among transmission categories, race/ethnicity groups or sexes. There were differences, however, in cause-specific mortality among the different risk groups.

No difference in the proportion of insulin receptor exon 11 +/- isoform mRNA in the liver of rats after development of hypertension

1. There are two functionally different isoforms of the insulin receptor in humans and rats. We hypothesized that a change in their relative proportion could be of relevance to insulin resistance in hypertension. 2. A reverse-transcriptase polymerase chain reaction technique was established for the detection of mRNA for the exon 11+ and exon 11- isoforms and the proportion of each was determined in 3, 6, 9 and 12 week old spontaneously hypertensive rats and Wistar-Kyoto rats, as well as adrenocorticotrophin (ACTH)-induced hypertensive rats and controls. 3. The proportion of the exon 11+ form (approximately 95%) and exon 11- form (approximately 5%) was similar in the liver of all rats studied. 4. We conclude that there is no change in insulin receptor isoform expression in the liver in the models of hypertension studied.

Colonization with group B streptococci in pregnancy and adverse outcome. VIP Study Group

OBJECTIVE

Our purpose was to study the association of cervicovaginal colonization with group B streptococci with pregnancy and neonatal outcome.

STUDY DESIGN

A prospective study was conducted at seven medical centers between 1984 and 1989. Genital tract cultures were obtained at 23 to 26 weeks' gestation and at delivery. Prematurity and neonatal sepsis rates were compared between group B streptococci positive and negative women.

RESULTS

Group B streptococci was recovered from 2877 (21%) of 13,646 women at enrollment. Heavy colonization was associated with a significant risk of delivering a preterm infant who had a low birth weight (odds ratio = 1.5, 95% confidence interval 1.1 to 1.9). Heavily colonized women given antibiotics effective against group B streptococci had little increased risk of a preterm, low-birth-weight birth. Women with light colonization were at the same risk of adverse outcome as the uncolonized women. Neonatal group B streptococci sepsis occurred in 2.6 of 1000 live births in women with and 1.6 of 1000 live births in women without group B streptococci at 23 to 26 weeks' gestation (p = 0.11). However, sepsis occurred in 16 of 1000 live births to women with and 0.4 of 1000 live births to women without group B streptococci at delivery (p < 0.001).

CONCLUSIONS

Heavy group B streptococci colonization of 23 to 26 weeks' gestation was associated with an increased risk of delivering a preterm, low-birth-weight infant. Cervicovaginal colonization with group B streptococci at 23 to 26 weeks' gestation was not a reliable predictor of neonatal group B streptococci sepsis. Colonization at delivery was associated with sepsis.

ZP3 peptide vaccine that induces antibody and reversible infertility without autoimmune oophoritis

Autoantibodies to ZP3, a major glycoprotein of the zona pellucida (ZP) with sperm receptor function, can block sperm/oocyte interaction. However, only mice of certain major histocompatibility complex (MHC) haplotype respond to the ZP3 peptide. Moreover, ZP3-specific T cells can mediate ovarian autoimmune disease. A chimeric peptide has been designed that induces antibody to native ZP3 regardless of the MHC haplotype of the inbred mice tested. This results in reduction in fertility that is reversible. Infertility correlates well with ZP antibody titer, and the mice do not develop concomitant autoimmune oophoritis. The vaccine contains (1) a promiscuous foreign T-cell peptide capable of eliciting a T-cell response regardless of the animals' MHC haplotype, and (2) a modified native B-cell peptide of ZP3.

A zona pellucida 3 peptide vaccine induces antibodies and reversible infertility without ovarian pathology

Zona pellucida 3 (ZP3) is a major glycoprotein of the zona pellucida that possesses the sperm receptor function. ZP3 induces autoantibody that can block sperm/oocyte interaction. However, the feasibility of a ZP3 contraceptive vaccine has been marred by the finding that ZP3-specific T cells mediate ovarian autoimmune disease. Moreover, as reported in this work, only some inbred mouse strains respond to the ZP3 peptide. We now describe a chimeric peptide that induces Abs to native ZP3 regardless of the MHC haplotype of the inbred mice tested. Study in one mouse strain resulted in reduction in fertility that correlates well with zona pellucida Ab titer, and most importantly, the mice do not develop concomitant autoimmune oophoritis. Moreover, the infertility was completely reversible. The design of the vaccine chimeric peptide is governed by the inclusion of two essential components: 1) a promiscuous foreign T cell peptide capable of eliciting a Th cell response regardless of the MHC haplotype of the animals, and 2) the native B cell peptide of ZP3 that has been modified by substitution of residue(s) critical for T cell but not B cell response to ZP3.

A zona pellucida 3 peptide vaccine induces antibodies and reversible infertility without ovarian pathology

Zona pellucida 3 (ZP3) is a major glycoprotein of the zona pellucida that possesses the sperm receptor function. ZP3 induces autoantibody that can block sperm/oocyte interaction. However, the feasibility of a ZP3 contraceptive vaccine has been marred by the finding that ZP3-specific T cells mediate ovarian autoimmune disease. Moreover, as reported in this work, only some inbred mouse strains respond to the ZP3 peptide. We now describe a chimeric peptide that induces Abs to native ZP3 regardless of the MHC haplotype of the inbred mice tested. Study in one mouse strain resulted in reduction in fertility that correlates well with zona pellucida Ab titer, and most importantly, the mice do not develop concomitant autoimmune oophoritis. Moreover, the infertility was completely reversible. The design of the vaccine chimeric peptide is governed by the inclusion of two essential components: 1) a promiscuous foreign T cell peptide capable of eliciting a Th cell response regardless of the MHC haplotype of the animals, and 2) the native B cell peptide of ZP3 that has been modified by substitution of residue(s) critical for T cell but not B cell response to ZP3.

Pulmonary function tests in HIV-infected patients without AIDS. Pulmonary Complications of HIV Infection Study Group

To determine the prevalence, incidence, and types of lung diseases that occur in association with HIV infection, 1,353 subjects, including HIV-seropositive homosexual men, injection drug users, female sexual partners of HIV-positive men, and HIV-seronegative control subjects from the first two transmission categories were evaluated prospectively in a multicenter study. Patients with AIDS at the time of initial evaluation were excluded. One thousand two-hundred ninety-four subjects who had no AIDS-defining diagnosis within 3 mo of enrollment had measurements of FVC, FEV1 and DLCO at the time of enrollment. As a group, all subjects had mean values of FVC and FEV1 close to 100% predicted. Those with CD4 counts below 200/mm3 had slightly reduced DLCO compared with the others. Subjects with a history of HIV-associated symptoms (thrush, weight loss, herpes zoster) also had a reduced DLCO compared with those without symptoms. Injection drug users had reduced FVC, FEV1 and DLCO compared with homosexual men and female sexual partners of HIV-infected men, with DLCO more substantially reduced. Part of the reduction in DLCO in drug users was attributable to factors other than HIV infection, especially cigarette smoking and race. Using predicted values that take cigarette smoking into account, the prevalence of abnormality in DLCO was higher among injection drug users (33.3%) than among homosexual men (11.2%) and female sexual partners (12.7%). These results show that advanced HIV infection, characterized by CD4 count < 200/mm3 or HIV-associated symptoms, and factors unrelated to HIV infection, including race, cigarette smoking, and injection drug use, are all associated with reductions in DLCO measurements.

A Combinatorial Approach to Materials Discovery

A method that combines thin film deposition and physical masking techniques has been used for the parallel synthesis of spatially addressable libraries of solid-state materials. Arrays containing different combinations, stoichiometries, and deposition sequences of BaCO(3), Bi(2)O(3), CaO, CuO, PbO, SrCO(3), and Y(2)O(3) were generated with a series of binary masks. The arrays were sintered and BiSrCaCuO and YBaCuO superconducting films were identified. Samples as small as 200 micrometers by 200 micrometers in size were generated, corresponding to library densities of 10,000 sites per square inch. The ability to generate and screen combinatorial libraries of solid-state compounds, when coupled with theory and empirical observations, may significantly increase the rate at which novel electronic, magnetic, and optical materials are discovered and theoretical predictions tested.

Interaction between fibronectin-bearing surfaces and Bacillus Calmette-Guérin (BCG) or gelatin microparticles

Gelatin, prepared commercially by degradation of animal collagen, was studied to see whether it had an affinity for fibronectin, which has a known affinity for collagen, and whether gelatin-based drugs could be used to target fibronectin-excreting tumours. Bacillus Calmette-Guérin (BCG) vaccine, an attenuated strain of Mycobacterium bovis, is currently the most effective treatment for superficial transitional cell carcinoma of the bladder. The living cells of the BCG vaccine associate with the fibronectin-bearing surfaces of the tumour. Using a multi-well culture plate technique, gelatin microparticles were shown to be adsorbed onto murine S180 sarcoma cells and this reaction was substantially inhibited by the addition of human plasma fibronectin. The avidities of various BCG substrains and gelatin microparticles for glass-bound fibronectin were measured and the association constants determined. The gelatin microparticles associated with the fibronectin with equal avidity as the BCG cells. The results suggest that this model system may allow the investigation of gelatin-based drug delivery devices capable of targeting fibronectin-bearing surfaces associated with some tumours.

The use of gelatin microparticles to delay the release of readily water-soluble materials

The adsorption of D-arabinose onto gelatin microparticles demonstrated a Langmuirian adsorption pattern. Evaluation of the dissolution behaviour of D-arabinose-loaded gelatin microparticles suggested that the saccharide, loaded at a level below the adsorption saturation level, was released uniformly over a 14-h period after the loaded gelatin microparticles had been lyophilized for a second time. When dissolution curves were corrected for the initial burst effect seen after the gelatin microparticles had been loaded at higher levels of D-arabinose and lyophilized, steady-state release rates were also evident over prolonged periods. In addition, it was evident that the D-arabinose was adsorbed onto internal surfaces of the hydrated gelatin matrix. Calculation of this internal surface demonstrated the influence of the concentration of the glutaraldehyde used as a cross-linking agent and this parameter, in turn, influenced both the adsorption maxima and the subsequent equilibrium release rates. Application of this data base to a highly water-soluble complex polysaccharide antineoplastic agent, which has a higher molecular weight (22.4 kDa vs 150 Da), demonstrated similar behaviour in that a near zero-order release pattern over at least 16 h could be obtained by attention to the conditions under which the gelatin microparticles were made and subsequently loaded before lyophilization.

In-vivo and in-vitro targeting of a murine sarcoma by gelatin microparticles loaded with a glycan (PS1)

PS1, a complex polysaccharide derived from Mycobacterium bovis (Bacillus Calmette-Guérin, BCG) with considerable antitumor activity in-vivo, was loaded onto gelatin microparticles (mean diam. 1.45 micron) at a level shown to not produce the burst effect often seen with drug-loaded microparticulate systems. In-vitro dissolution experiments had demonstrated a sustained-release behaviour, with a half-life of approximately 8 h for what is an extremely water-soluble material. These PS1/gelatin systems had no measurable cytotoxicity against an S180 murine sarcoma cell in-vitro although fibronectin-mediated targeting of the microparticles for the tumour cells could be demonstrated. Injection into mice, with the S180 cells, of PS1 solutions or suspensions of PS1-loaded gelatin microparticles resulted in almost identical dose-related suppression for the tumour cell growth. When injected at intervals following injection of the tumour cells, however, for a period of 24-48 h there was a relatively enhanced activity of the formulated PS1, compared with the aqueous solution, after which both formulated and unformulated material became progressively less effective.

Initial characterization of an antineoplastic, polysaccharide-rich extract of Mycobacterium bovis BCG, Tice substrain

A purified hot-water extract from Mycobacterium bovis (BCG vaccine) has been found to have significant antitumor activity against a murine sarcoma in vivo, but not in vitro, suggesting that the active compound is behaving as an immunostimulant. The material, termed PS1, has an average molecular weight of 22.4 kDa, is freely soluble in water, but has low solubility in acetone or ethanol, and is remarkably heat-stable, as is the parent BCG vaccine in terms of high-dose antitumor activity. PS1 contains at least 50% carbohydrate, consisting mainly of glucose, galactose and mannose, and about 10% lipid that may correspond to phosphatidylinositol. It shares chemical and biological properties with an arabinomannan isolated from M. tuberculosis, but it contains only trace quantities of lipoarabinomannan (LAM). Crossed immunoelectrophoresis indicated that PS1 contains the mycobacterial antigen 89, but only a single, non-migrating precipitin arc appeared on immunoelectrophoresis against a standard anti-BCG serum. PS1 appears to be non-toxic in mice up to a dose of 5 mg/kg, while as little as 70 micrograms/kg is sufficient to inhibit tumor formation significantly.

T cell peptide of a self-protein elicits autoantibody to the protein antigen. Implications for specificity and pathogenetic role of antibody in autoimmunity

A 13-mer peptide of the ZP3 glycoprotein from mouse zona pellucida has a T cell epitope that induces autoimmune oophoritis and a B cell epitope that reacts with antibody to murine ZP3. When the B cell epitope was partially truncated, the ZP3 peptides no longer induced antibody to the B cell epitope, but unexpectedly they elicited antibody to the zona pellucida. These autoantibodies were of IgG class, detected in sera and bound to the ovarian zona pellucida. That an exclusive T cell peptide of murine ZP3, without coinjection of the whole ZP3 protein, elicited autoantibodies against ZP3 outside the T cell peptide was confirmed as follows. First, the ZP3 T cell peptide did not contain additional B cell epitopes that cross-reacted with native ZP3. Second, endogenous ovarian Ag were required because autoantibodies were not detected in ovariectomized mice immunized with ZP3 peptides lacking the B epitope. This autoantibody amplification phenomenon demonstrates conclusively that 1) self-reactive B cells for ovarian autoantigens respond to endogenous ovarian Ag in vivo after activation of ZP3-specific Th cells and 2) serum antibody in an autoimmune disease need not mirror the immunogen that initiates the disease process. Nonetheless, the autoantibodies bound to the zona pellucida in vivo and are potentially important in disease pathogenesis.

T cell peptide of a self-protein elicits autoantibody to the protein antigen. Implications for specificity and pathogenetic role of antibody in autoimmunity

A 13-mer peptide of the ZP3 glycoprotein from mouse zona pellucida has a T cell epitope that induces autoimmune oophoritis and a B cell epitope that reacts with antibody to murine ZP3. When the B cell epitope was partially truncated, the ZP3 peptides no longer induced antibody to the B cell epitope, but unexpectedly they elicited antibody to the zona pellucida. These autoantibodies were of IgG class, detected in sera and bound to the ovarian zona pellucida. That an exclusive T cell peptide of murine ZP3, without coinjection of the whole ZP3 protein, elicited autoantibodies against ZP3 outside the T cell peptide was confirmed as follows. First, the ZP3 T cell peptide did not contain additional B cell epitopes that cross-reacted with native ZP3. Second, endogenous ovarian Ag were required because autoantibodies were not detected in ovariectomized mice immunized with ZP3 peptides lacking the B epitope. This autoantibody amplification phenomenon demonstrates conclusively that 1) self-reactive B cells for ovarian autoantigens respond to endogenous ovarian Ag in vivo after activation of ZP3-specific Th cells and 2) serum antibody in an autoimmune disease need not mirror the immunogen that initiates the disease process. Nonetheless, the autoantibodies bound to the zona pellucida in vivo and are potentially important in disease pathogenesis.

Inhibition of murine sarcoma cell adherence to polystyrene substrata by bacillus Calmette-Guérin: evidence for fibronectin-mediated direct antitumor activity of BCG

Bacillus Calmette-Guérin (BCG) inhibited adherence of S180 mouse sarcoma cells and WI38 human diploid fibroblasts to the polystyrene substratum of 24-well cluster dishes in a dose-dependent manner. This property was retained by washed or heat-killed bacilli, but not by the vaccine filtrate or by the spent bacterial culture medium. Adhesion of bacilli to nonadherent S180 cells was demonstrated by light and scanning electron microscopy, but was not seen after trypsinization of adherent cells, indicating that bacilli bind to cell-surface adhesins. Preincubation of bacilli with human fibronectin abolished their ability to inhibit S180 adherence, suggesting that the phenomenon may be mediated by interaction of bacilli with cell-surface fibronectin. Fibronectin pretreatment of the bacteria also decreased their inhibition of S180 tumor growth in vivo, indicating that this mechanism may be at least partly responsible for BCG vaccine's observed antineoplastic activity.