Antibodies to diphtheria, tetanus and pertussis in infants before and after immunization with DTP (Triple Antigen) vaccine

Objective : To determine antibody levels to the Australian manufactured combined diphtheria, tetanus and pertussis (DTP) vaccine (Triple Antigen, CSL Ltd) in infante before and after their primary immunization course.
Methodology : Serosurvey (antibody prevalence study) in two groups: infants aged 5-9 weeks who had not received any immunizations ( n = 25), and infants aged 7-10 months who had received two ( n = 25) or three immunizations ( n = 57) with DTP, sampled from infants attending the Royal Children's Hospital, Melbourne, either as inpatients or outpatients between February and April 1993. The immunization history for each infant was determined from hospital records, the parent-held child health record, or the local council or family doctor who immunized the infant.
Results : Enzyme immunoassay (EIA) of antibodies to diphtheria and tetanus showed all infants to have adequate protective levels after two or three vaccinations (£0.01 IU/mL). All subjects who had received all three DTP vaccinations had detectable antibody to at least one pertussis antigen. Antibodies to the pertussis antigens filamentous haemagglutinin and pertussigen (pertussis toxin) were comparable to levels determined for whole cell pertussis vaccines used elsewhere in the world. EIA-determined antibodies to pertussis agglutinogen type 2 and agglutinogen type 3 showed substantially higher geometric mean titres when results for pre-immunization and post-immunization subjects were compared.
Conclusions : These data show that the Australian manufactured DTP vaccine has immunogenic properties similar to those of vaccines used elsewhere, and that antibody concentrations following immunization are at levels consistent with efficacy.     

IL-12 eliminates the Th-2 dependent protective immune response of mice to larval Strongyloides stercoralis

The goal of the present study was to determine if immune-mediated killing of S. stercoralis L3 in mice could be modulated by shifting from a Th-2 to a Th-1 type immune response. L3 killing in immunized mice was ablated in CD4⁺ T cell-depleted animals, but not in CD8⁺ T cell-depleted or β2-microglobulin-deficient mice. Treatment of immunized mice with IL-4 or IL-5 neutralizing MoAb significantly reduced the protective effects of vaccination against S. stercoralis , while protective immunity was unimpaired in IFN-γ knockout mice. Recombinant IL-12 was administered to infected mice to switch the immune response from a Th-2 to a Th-1 type response. Protective immunity was ablated in immunized mice that received IL-12 therapy. Eosinophil numbers, eosinophil peroxidase levels, and parasite-specific IgG1 levels were lowered in IL-12 treated immunized animals, and parasite-specific IgG2a levels were increased in these animals. The data indicate that eosinophils are important as mediators of larval killing, and that the establishment of Th-2 type immunity results in killing of infective S. stercoralis L3, while a shift to Th-1 type immunity abrogates protective responses.     

Disposition of the Aromatase Inhibitor LY56110 and Associated Induction and Inhibition Studies in Rats, Dogs, and Monkeys

Disposition of the Aromatase Inhibitor LY56110 and AssociatedInduction and Inhibition Studies in Rats, Dogs, and Monkeys.LINDSTROM, T. D., AND WHITAKER, G. W. (1987). Fundam. Appl.Toxicol. 8, 595–604. Compound LY56110 was well absorbedbut slowly excreted in the rat, dog, and monkey. Oral administrationof 5 mg/kg of [¹⁴C]LY56110 (5-bis(4-chlorophe-nyl)methylpyrimidine)to the rat, monkey, and dog resulted in a total excretion of68, 65, and 30% of the radioactivity within 5 days, respectively.Very low urinary excretion was observed in the rat and dog (2%),with fecal excretion being the predominant mode of eliminationin all three species. The plasma radioactivity half-life was49, 41, and greater than 100 hr in the rat, monkey, and dog,respectively. The plasma half-life of parent compound was 18hr in the rat and 10 hr in the dog. LY56110 accounted for only25, 12, and 1% of the plasma radioactivity area under the curvein the rat, dog, and monkey, respectively. High levels of radioactivitywere observed in the target tissues of fat, adrenals, and ovariesof rats. LY56110 induced hepatic cytochromes b₅ and P-450 andcytochrome c reductase in rats after 14 days of oral dosingat 10 mg/kg but not in monkeys after 10 days of oral dosingat 10 mg/kg. The compound was more potent than aminoglutethimideor cimetidine in inhibiting hepatic ethylmorphine and p-nitro-anisoledemethylase activity in vitro. LY56110 also inhibited ethinamate-inducedsleeping time in rats in vivo. The compound induced a reversetype I binding spectrum with rat ovarian microsomes.     

Hyperventilation Facilitates Induction of Supraventricular Tachycardia: A Novel Method and the Possible Mechanism

INTRODUCTION: Hyperventilation has been demonstrated to alter autonomic function. Sympathomimetic drugs (isoproterenol) and parasympatholytic drugs (atropine) may be needed to facilitate induction of supraventricular tachycardia (SVT). The aim of this study was to test the clinical utility and mechanisms of hyperventilation to facilitate SVT initiation. METHODS AND RESULTS: Fourteen patients with clinically documented SVT (9 AV nodal reentrant tachycardia and 5 AV reciprocating tachycardia) but noninducible during baseline electrophysiologic study were included. Immediately after hyperventilation test (at least 30 respirations/min) for 2 minutes, systolic blood pressure, sinus cycle length, anterograde and retrograde 1:1 conduction, and induced SVT were measured. Arterial blood gas, pH, and heart rate variability before and after hyperventilation were measured. Seven of nine patients with AV nodal reentrant tachycardia and 3 of 5 patients with AV reciprocating tachycardia could be induced immediately after the hyperventilation test. After hyperventilation, anterograde AV and retrograde VA 1:1 conduction were improved, sinus cycle length was decreased, and heart rate variability were decreased in both groups. CONCLUSION: Hyperventilation can facilitate induction of SVT. Improvement of conduction properties and changes of autonomic function are the possible mechanisms.     

Evaluation of Lactobacillus Preparation on Enterotoxigenic E. Coli-induced Rabbit Ileal Loop Reactions

A commercially available lactobacillus-containing preparation has been used extensively in the treatment of diarrhea but few laboratory tests have been performed to determine the efficacy of this product. The rabbit ileal loop reaction was used here to determine the effect of the lactobacillus preparation and its ingredients on E. coli enterotoxin-induced loop fluid response. Enterotoxigenic E. coli cells grown overnight in shake cultures were washed and resuspended in saline to the original volume. They were then diluted in TSB suspensions of the lactobacillus preparation or its ingredients and injected into ileal loops. E. coli diluted in TSB served as positive controls. Fluid response was measured after 18 hours and the loop fluid ratio (LFR) (ml./cm.) of the lactobacillus preparations was compared to the positive controls. The positive controls always showed a high loop fluid ratio (> 1.1 ml./cm.) and negative saline controls showed no fluid response. The lactobacillus granules and tablets had low LFR's (0.08 and 0.05, respectively). Ingredients (whey, talc, sugar, evaporated milk, mineral oil) had variable LFR's (0.65, 0.78, 1.39, 1.46 and 1.54, respectively). Individual ingredients used to make this preparation show little antifluid response when used separately but the final product exhibits a significant antienterotoxin response.     

An interview study of participants in the Tacoma, Washington, syringe exchange

Although European and Australian studies of syringe exchange programs have reported safer injection among participants and no increase in drug use, the generalizability of these findings to the US is uncertain. We report on the operations and potential effectiveness of the longest-operating syringe exchange in the US and compare our results to studies of exchange programs outside the US. The sample of 204 study subjects reported no change in the frequency of injection, from 155 to 152 injections per month, and a decline in the frequency of unsafe injections, from 56 to 30 times per month, while participating in the program. In all studies, participants report reduction in unsafe injections, and no increase in illicit drug use. However, the comparison also suggests that a high proportion of Tacoma exchangers have higher initial rates of drug injection, unsafe injection and homelessness, all of which were associated with unsafe injection while using the exchange. These indicate a need for additional services but that the Tacoma program is no less effective than European and Australian programs.     

COMPARISON OF NASAL CANNULAE WITH FACE MASK FOR OXYGEN ADMINISTRATION TO POSTOPERATIVE PATIENTS

Thirty postoperative patients were allocated randomly to receiveoxygen by Hudson face mask at 4 litre min-1 (group I) or 2 litremin-1 (group II) via nasal cannulae. From 22:00 on the firstnight after operation, the position of the nasal cannula orface mask was observed for 8h using video and oxyhaemoglobinsaturation (Sp02) recorded simultaneously. In group I the maskremained on and positioned correctly in five patients. In the10 other patients it was removed a total of 28 times, 17 fornursing tasks, for a median time of 2 min 39 s (range 30 s to7 h 40 min 40 s). In group II the nasal cannua was removed oncein one patient for 16 min 38 s and eight times in another fora total of 1 h 18 min 7s. Average SpOj with mask on was 98%(range 96.1–99.9%), with mask off 95% (range 89.8–98.8%)and with cannula 97% (range 90.8–99.3%). We conclude thatnasal cannulae are more likely to remain in position than facemasks and maintain an adequate saturation in most patients.(Br. J. Anaesth. 1993; 70: 440–442)