Oral immunization with a shiga toxin B subunit: rotavirus NSP4(90) fusion protein protects mice against gastroenteritis

A fusion protein containing the shiga toxin-1 B subunit (STB) linked to a 90 amino acid peptide (aa residues 86--175) from simian rotavirus (SA--11) nonstructural protein NSP4 was synthesized in Escherichia coli. Mice orally inoculated with 60 microg of STB::NSP4(90) fusion protein per dose generated higher humoral and intestinal antibody titers than mice inoculated with 30 microg of NSP4 alone. Serum anti-NSP4 IgG2a isotype titers were substantially greater than IgG1 titers, suggesting a dominant Th1 immune response. ELISA measurement of cytokines secreted from splenocytes isolated from immunized mice confirmed the STB::NSP4(90) fusion protein stimulation of a strong Th1 cell mediated immune response. Diarrhea in SA-11 rotavirus challenged neonates suckling from STB::NSP4 immunized dams was significantly reduced in severity and duration in comparison with virus challenged neonates from unimmunized mice. Together, our experiments demonstrate for the first time that the shiga toxin B subunit provides ligand mediated delivery of virus antigens to the gut-associated lymphoid tissues for enhanced stimulation of humoral and cellular responses against rotavirus gastroenteritis.     

The correction of cerebrovascular insufficiency by transluminal dilatation: a preliminary report

Transluminal angioplasty is being extensively utilized to dilate arteriosclerotic lesions. However, this technique has not been widely used for the treatment of cerebrovascular insufficiency. This report describes the application of transluminal angioplasty to relieve cerebral ischemia secondary to extracranial arterial stenosis. A total of 10 patients presented with symptoms of vertebrobasilar insufficiency. Bilateral upper extremity pressures were measured prior to the performance of arteriography on all patients. Significant stenoses were found in the subclavian artery (9) and in the innominate artery (1). Dilating catheters were passed retrograde through surgically exposed brachial and common carotid arteries. Transluminal angioplasty under fluoroscopic control was attempted. Anatomic correction of all lesions was achieved without hemorrhagic or embolic complications. The mean increase in brachial systolic pressure was 38.2 mm Hg postdilatation. Initial symptomatic relief was total in seven patients, partial in two, and absent in one. It is believed that associated small vessel brain stem disease accounted for the less than total relief of symptoms of these three patients. Average follow-up for all patients was 13 months with one recurrent subclavian artery stenosis occurring at three months postangioplasty. Preliminary results suggest that some patients with cerebral ischemia secondary to extracranial arterial stenosis can be treated safely by transluminal angioplasty.     

Retrospective analysis of weekly topotecan as salvage therapy in relapsed ovarian cancer

OBJECTIVE: To retrospectively investigate the safety and efficacy of weekly topotecan in heavily pretreated patients with ovarian cancer. METHODS: Data were collected by retrospective review of patient records. Eligible patients had received > or =2 prior regimens for ovarian cancer before treatment with weekly topotecan. Efficacy was determined by measurable disease or CA 125 levels. Adverse event and growth factor support data were also collected. RESULTS: Fifty patients (median age, 61 years) were evaluable for safety and received a total of 244 4-week cycles of therapy (median, 3; range, 1-21 cycles). Most patients (84%) had measurable disease, and 30% had performance status of > or =2. Patients had received two to six prior treatments for ovarian cancer. Median weekly dose per patient was topotecan 3.7 mg/m(2). Grade 4 hematologic toxicities (generally manageable) occurred in 4% of patients. One patient had febrile neutropenia. Grade 3/4 nonhematologic toxicities were fatigue in two (4%) patients. Forty-two patients were evaluable for response. Of 35 evaluable patients with measurable disease, 11 (31%) had a partial response (median duration, 3 months), and 15 (43%) patients had stable disease (median duration, 3.5 months). Of 41 evaluable patients with elevated CA 125 (median, 154 U/l; range, 47-7200 U/l), 11 (27%) had > or =50% decreases or normalization of CA 125 levels. Median time to progression in all patients with stable disease has not been reached (follow-up range, 1.5-17.3 months). CONCLUSIONS: Weekly topotecan is active and well tolerated in heavily pretreated patients with relapsed ovarian cancer. Prospective studies of this regimen are warranted.     

Combined measurement of ferritin, soluble transferrin receptor, retinol binding protein, and C-reactive protein by an inexpensive, sensitive, and simple sandwich enzyme-linked immunosorbent assay technique

The measurement of vitamin A (VA) and iron status is very important in the assessment of nutritional deficiencies. The objective of this research was to develop a sandwich ELISA technique for the simultaneous measurement of ferritin, soluble transferrin receptor, retinol binding protein, and C-reactive protein (CRP) as indicators for VA and iron status. The inclusion of CRP as marker of infection allows for more accurate interpretation of VA and iron status. This is accomplished in a 30-microL serum or plasma sample using an ELISA with different capture and detection antibodies and different dilutions of the sample. Commercially available clinical serum controls were used for calibration purposes. The developed assays were compared to commercially available traditional tests. Regression coefficients comparing both assays were better than 0.84 (P < 0.001). Using a limited sample set, the sandwich ELISA assay produced very similar specificity and sensitivity compared to traditional methods when common cutoff values were applied. Intra- and interassay variability was between 5 and 14% for all tests. The cost of the materials for all 5 measurements decreases to less than $1/sample if a large number of samples is analyzed. Due to the low cost, high throughput, and comparability to traditional tests, this procedure has several advantages for assessing VA and iron status in population surveys.     

Peripheral blood-derived bovine dendritic cells promote IgG1-restricted B cell responses in vitro

Regulation of humoral responses involves multiple cell types including the requirements for cognate interactions between T and B cells to drive CD40-dependent responses to T-dependent antigens. A third cell type has also been shown to play an essential role, the dendritic cell (DC). We demonstrate that bovine peripheral blood-derived (PB)-DC are similar in function to features described for human interstitial DC including the production of signature type 2 cytokines [interleukin (IL)-13, IL-10]. PB-DC express moderate-to-high costimulatory molecule expression, and major histocompatibility complex class II is negative for CD14 expression and has low or no expression of CD11c. Consistent with the interstitial phenotype is the ability of PB-DC to influence B cell activation and differentiation via direct expression of CD40L and type 2 cytokines. Collectively, these results suggest that direct B cell-DC interactions may promote an immunoglobulin-isotype expression pattern consistent with type 2 responses, independent of direct T cell involvement.     

A randomized clinical trial of treatment of clomiphene citrate-resistant anovulation with the use of oral contraceptive pill suppression and repeat clomiphene citrate treatment

OBJECTIVE: The purpose of this study was to evaluate the effectiveness and endocrine response of oral contraceptive ovarian suppression followed by clomiphene citrate in patients who previously were clomiphene citrate resistant. STUDY DESIGN: Forty-eight patients from a private tertiary infertility clinic were assigned randomly prospectively to either group 1 (oral contraceptive/clomiphene citrate), which received continuous oral contraceptives followed by clomiphene citrate, or to group 2 (control) received no treatment in the cycle before clomiphene citrate treatment. On day 3, 17 beta-estradiol, follicle-stimulating hormone, luteinizing hormone, and androgens were assayed before and after treatment. Follicle growth, ovulation, and pregnancy were evaluated. The Student t test and analysis of variance were used for statistical significance. RESULTS: The oral contraceptive/clomiphene citrate group had a significantly higher percentage of patients who ovulated and of ovulatory cycles and pregnancies. Significantly lower levels of 17 beta-estradiol, luteinizing hormone, and androgen levels were seen in the oral contraceptive/clomiphene citrate group, with no significant changes in group 2. CONCLUSION: Suppression of the ovary with oral contraceptives results in excellent rates of ovulation and pregnancy in patients who previously were resistant to clomiphene citrate. The decreases in ovarian androgens, luteinizing hormone, and 17 beta-estradiol may be responsible for the improved response.