The effectiveness of germicidal wipes and ultraviolet irradiation in reducing bacterial loads on electronic tablet devices used to obtain patient information in orthopaedic clinics: evaluation of tablet cleaning methods

BACKGROUND

Electronic tablet devices are commonly used in outpatient clinics to obtain patient information for both clinical and research purposes. These devices are often colonized with bacteria; there are many cleaning methods to reduce this bacterial load.

AIM

The primary purpose of this study was to evaluate whether regular cleaning with either germicidal wipes or ultraviolet (UV) irradiation leads to lower bacterial levels compared with irregular cleaning.

METHODS

A randomized blinded trial was conducted of tablet cleaning strategies between each patient encounter in orthopaedic clinics. The cleaning method was randomized to either germicidal wipes, UV irradiation, or cleaning only when the tablet was visibly soiled. Research assistants (blinded to the treatment) obtained bacterial cultures from the tablets at the beginning and end of each clinic day.

FINDINGS

Using germicidal wipes between each patient encounter vs no routine cleaning resulted in a marked decrease in the amount of bacterial contamination (risk ratio (RR) = 0.17 (0.04-0.67)). Similarly, using UV irradiation between each patient encounter led to significantly lower bacterial contamination rates (RR = 0.29 (95% confidence interval (CI) = 0.09-0.95)) compared with no routine cleaning. The majority of bacteria identified were normal skin flora. No meticillin-resistant Staphylococcus aureus was identified and only sparse colonies of meticillin-sensitive S. aureus.

CONCLUSION

Electronic tablets used in orthopaedic trauma clinics are colonized with bacteria if no routine cleaning is performed. Routine use of either UV irradiation or germicidal wipes significantly decreases this bacterial burden. Providers should implement routine cleaning of tablets between each patient encounter to minimize exposure to potential pathogens.

A novel real-time polymerase chain reaction method for high throughput quantification of small regulatory RNAs

MicroRNAs (miRNAs) and small interfering RNAs (siRNAs) are important players of both transcriptional and post-transcriptional gene silencing networks. In order to investigate the functions of these small regulatory RNAs, a system with high sensitivity and specificity is desperately needed to quantitatively detect their expression levels in cells and tissues. However, their short length of 19-24 nucleotides and strong similarity between related species render most conventional expression analysis methods ineffective. Here we describe a novel primer for small RNA-specific reverse transcription and a new TaqMan technology-based real-time method for quantification of small RNAs. This method is capable of quantifying miRNA and siRNA in the femtomolar range, which is equivalent to ten copies per cell or fewer. The assay has a high dynamic range and provides linear readout of miRNA concentrations that span seven orders of magnitude and allows us to discriminate small RNAs that differ by as little as one nucleotide. Using the new method, we investigated the expression pattern of gma-miRMON1, a novel miRNA identified from soybean leaves. The results were consistent with our results obtained from Northern blot analysis of gma-miRMON1 and Affymetrix microarray analysis of the gma-miRMON1 precursor, suggesting that the new method can be used in transcription profiling.

Periodontitis and type 2 diabetes: is oxidative stress the mechanistic link?

Periodontitis is a common, chronic inflammatory disease initiated by bacteria which has an increased prevalence and severity in patients with type 2 diabetes. Recent studies indicate that the co-morbid presence of periodontitis can, in turn, adversely affect diabetic status and the treatment of periodontitis can lead to improved metabolic control in diabetes patients. Current evidence points to a bidirectional interrelationship between diabetes and inflammatory periodontitis. The importance of oxidative stress-inflammatory pathways in the pathogenesis of type 2 diabetes and periodontitis has recently received attention. Given the bidirectional relationship between these two conditions, this review discusses the potential synergistic interactions along the oxidative stress-inflammation axis common to both type 2 diabetes and periodontitis, and the implications of this relationship for diabetic patients.

Attitudes, awareness and oral health-related quality of life in patients with diabetes

The purpose of this study was to assess the knowledge diabetic patients have of their risk for periodontal disease, their attitude towards oral health and their oral health-related quality of life (OHRQL). One hundred and one consecutive patients (age range 31-79 years) recruited from a diabetic outpatient clinic participated in the study. Twenty-seven per cent of participants had type 1 diabetes, 66% type 2 and 7% did not know what type of diabetes they had. The length of time since participants were diagnosed as diabetic ranged from 1 to 48 years. Metabolic control of diabetes as determined by HbA1c levels ranged from 6.2% to 12.0% compared with the normal range of 4.5-6.0%. Thirty-three per cent of participants were aware of their increased risk for periodontal disease, 84% of their increased risk for heart disease, 98% for eye disease, 99% for circulatory problems and 94% for kidney disease. Half of the participants who were aware of their increased risk for periodontal disease had received this information from a dentist. Dental attendance was sporadic, with 43% reporting attendance within the last year. OHRQL was not significantly affected by the presence of diabetes in the group surveyed, in comparison with a previous survey of non-diabetic patients. A significant association was found between metabolic control and dentate status. Awareness of the potential associations between diabetes, oral health and general health needs to be increased in diabetic patients.

Base-pairing between untranslated regions facilitates translation of uncapped, nonpolyadenylated viral RNA

Translationally competent mRNAs form a closed loop via interaction of initiation factors with the 5' cap and poly(A) tail. However, many viral mRNAs lack a cap and/or a poly(A) tail. We show that an uncapped, nonpolyadenylated plant viral mRNA forms a closed loop by direct base-pairing (kissing) of a stem loop in the 3' untranslated region (UTR) with a stem loop in the 5' UTR. This allows a sequence in the 3' UTR to confer translation initiation at the 5'-proximal AUG. This base-pairing is also required for replication. Unlike other cap-independent translation mechanisms, the ribosome enters at the 5' end of the mRNA. This remarkably long-distance base-pairing reveals a novel mechanism of cap-independent translation and means by which mRNA UTRs can communicate.

Base-pairing between untranslated regions facilitates translation of uncapped, nonpolyadenylated viral RNA

Translationally competent mRNAs form a closed loop via interaction of initiation factors with the 5' cap and poly(A) tail. However, many viral mRNAs lack a cap and/or a poly(A) tail. We show that an uncapped, nonpolyadenylated plant viral mRNA forms a closed loop by direct base-pairing (kissing) of a stem loop in the 3' untranslated region (UTR) with a stem loop in the 5' UTR. This allows a sequence in the 3' UTR to confer translation initiation at the 5'-proximal AUG. This base-pairing is also required for replication. Unlike other cap-independent translation mechanisms, the ribosome enters at the 5' end of the mRNA. This remarkably long-distance base-pairing reveals a novel mechanism of cap-independent translation and means by which mRNA UTRs can communicate.

IL-10 kinetics in thyroiditis-prone BB/Wor rats

Cytokines modulate the course of autoimmunity, but their role in the evolution of spontaneous disease is unclear. This study compared the cytokine kinetics of T cell cultures from thyroiditis (LT)-prone NB line BB/Wor rats with those of Wistar (Wis) rat controls following activation with the thyroid-specific antigen thyroglobulin (Tg) or Concanavalin A (Con A).

DESIGN

T cell enhanced splenocytes from 60 day old Wis and NB rats were activated with 0.5 microg/ml rat thyroglobulin (Tg) or Con A in the presence of homologous irradiated splenocytes as antigen presenting cells (APC's). In addition, the effect of APC's was determined in a crisscross experiment which examined NB T cell responses to Con A in the presence of Wis APC's. ELISA and RT-PCR were used to examine IL-2, IL-4, IL-10, TNFalpha, IFNgamma, IL-I0 concentrations and mRNA expression in the supernatant and cells from parallel cultures harvested at specific intervals. Frozen thyroids from 60 day old NB, Wis and Fisher rats were examined for the presence of IL-10 by immunohistochemistry. T cell proliferation was measured by 3H thymidine uptake.

RESULTS

Following activation with either Tg or Con A, IL-10 concentrations exceeded IFNgamma in NB rat cultures, but IFNgamma exceeded IL-10 in Wis cultures. Wis splenocytes significantly enhanced NB T cell proliferation and cytokine responses to Con A. Thyroids from 60 day NB rats contained IL-10, but no IFNgamma. There was no IL-10 in thyroids from Wistar or Fisher rats.

CONCLUSION

Splenocyte responses in LT-prone BB/Wor rats favor IL-10 production. Future investigations will examine the source of intrathyroidal IL-10 and its role in LT.

Liver transplantation improves cirrhosis-associated impaired oral glucose tolerance

BACKGROUND

Thirty-five percent to 80% of cirrhotic patients have impaired glucose tolerance (IGT) or diabetes mellitus (DM). Diabetic cirrhotics have higher morbidity and mortality than nondiabetics. Therefore, it would be worthwhile to determine whether liver transplantation improves glucose homeostasis in these patients.

METHOD

A total of 26 patients awaiting liver transplantation were evaluated for impaired glucose homeostasis by fasting blood glucose and/or oral glucose tolerance tests (OGTT). Five patients underwent transplant surgery within 1 year of OGTT and had a repeat OGTT 3-6 months after transplantation.

RESULTS

Sixty-five percent (17/26) of the patients had abnormal glucose homeostasis. Twenty-three percent (6/26) met American Diabetes Association criteria for DM, and another 42.3% (11/26) had IGT. All patients had normal HbA1C levels. After transplantation, the 2-hr blood glucose improved in four patients and the mean 2-hr glucose level was reduced (204 +/- 94 vs. 132 +/- 53 mg/dl [mean +/- SD, P=0.051]).

CONCLUSION

Liver transplantation can reverse cirrhosis-associated impaired glucose tolerance.

Water fluoridation and the sudden infant death syndrome

AIMS

To determine whether exposure to fluoridated water supplies prenatally or postnatally at the time of death increases the risk of sudden infant death syndrome (SIDS).

METHODS

A nationwide, case-control study, with infant's water fluoridation status determined from census area unit information for mother's usual address at the time of the infant's birth, infant's usual address at the time of death / nominated sleep and address where infant died / was at nominated sleep. SIDS risk associated with fluoride exposure postnatally was assessed according to method of infant feeding (breast or reconstituted formula), for the two days prior to infant's death / nominated sleep.

RESULTS

Infants exposed to fluoridated water supplies during pregnancy were not at increased risk for SIDS, adjusted odds ratio (OR) 1.19 (95% confidence interval (CI) 0.82, 1.74). For breast-fed infants at the time of death / nominated sleep, fluoridated water exposure was not associated with an increased risk for SIDS, adjusted OR 1.09 (95% CI 0.66, 1.79). Similarly, 'fluoridated' formula feeding, when compared with 'unfluoridated' formula feeding, showed no increased risk of SIDS, adjusted OR 1.25 (95% CI 0.73, 2.13). There was no evidence of an interaction between fluoridation and infant feeding for the last two days (chi2 = 0.171, df = 1, p = 0.68).

CONCLUSION

Exposure to a fluoridated water supply prenatally or postnatally at the time of death did not affect the relative risk for SIDS.

The effect of methimazole, iodine and splenocytes on thyroid transplants in BB/Wor rats

BACKGROUND

BB/Wor rats develop spontaneous autoimmune insulin-requiring diabetes mellitus and lymphocytic thyroiditis (LT). Our investigations examined the effect of the thyroid-specific agents, iodine and methimazole (MMI) on thyroid graft survival in BB/Wor rats, compared the intrathyroidal cytokine mRNA expression of endogenous and engrafted thyroids, and ascertained whether unfractionated splenocytes could protect thyroid grafts from lymphocytic infiltration.

METHODS

In study 1, 0.025% iodine water-treated LT-prone NB line BB/Wor rats were randomized to receive one of the following treatments: (1) 1.0 x 10(8) splenocytes, IV from LT-resistant WA line BB/Wor rats, (2) WA rat thyroid transplants, (3) both, or (4) neither (controls). In study 2, after thyroid transplantation, LT-prone BB/Wor rats were randomized to receive (1) WA splenocytes, (2) 0.025% iodine water, (3) 0.05% MMI water or, (4) tap water (controls). The incidence of LT was determined by microscopic inspection after hematoxylin and eosin staining. Lymphocytic infiltrates were characterized by immunohistochemistry. Cytokine mRNA was detected by RT-PCR.

RESULTS

Grafts from MMI-treated rats had a significantly lower incidence of lymphocytic infiltration (MMI: 2/5; Tap: 5/5; I 5/5, P<0.05, chi2). IL-10 mRNA was expressed in 77% (7/9) endogenous thyroids and 20% (1/5) of the transplanted WA thyroids (P<0.05, chi2) from iodine-treated rats with LT. There was no difference in IL-12 mRNA expression. Lymphocytic infiltration occurred in 100% of the splenocyte-treated graft recipients. Both endogenous and engrafted thyroids contained CD4 and C8 T cells with scattered IgG staining.

CONCLUSION

Target organ-specific interventions that suppress antigen presentation may have an adjunctive role in transplantation tolerance. The differential expression of IL-10 may indicate preferential Th2 lymphocyte activation in the endogenous tissues.

A randomized, controlled study of the 1-hour and 24-hour effects of inhaled nitric oxide therapy in children with acute hypoxemic respiratory failure

STUDY OBJECTIVE

To determine whether 24 h of inhaled nitric oxide improves oxygenation greater than conventional therapy alone in children with acute hypoxemic respiratory failure.

DESIGN

Prospective, randomized, controlled study.

SETTING

Twenty-six-bed pediatric ICU in a tertiary children's hospital.

PATIENTS

Twenty-four patients with acute bilateral lung disease requiring a positive-end expiratory pressure >6 cm H2O and a fraction of inspired oxygen >0.5 for >12 h.

INTERVENTIONS

Twelve patients were treated with 10 ppm inhaled nitric oxide from the onset of randomization and 12 control patients were initially maintained on a regimen of conventional therapy alone. After a period of 24 h, control patients were also treated with 10 ppm inhaled nitric oxide. Hemodynamic and blood gas measurements were performed at baseline, at 1 h after randomization, and at 24-h intervals for 2 days.

MEASUREMENTS AND RESULTS

Inhaled nitric oxide decreased the ratio of pulmonary to systemic vascular resistance and improved oxygenation indexes during the initial hour following randomization. However, 24 h after randomization, the oxygenation indexes of 11 surviving treated patients were not improved in comparison to baseline or the oxygenation indexes of 10 surviving control patients. Oxygenation indexes acutely improved in control patients when inhaled nitric oxide was started after 24 h of conventional therapy. Oxygenation indexes remained improved in the initial control patients after 24 h of inhaled nitric oxide.

CONCLUSIONS

Pulmonary vascular resistance and systemic oxygenation are acutely improved by 10 ppm inhaled nitric oxide in some children with severe lung disease. However, a sustained improvement in oxygenation may not occur during prolonged therapy. Thus, inhaled nitric oxide may have a limited therapeutic role in children with acute hypoxemic respiratory failure.

Life events, social support and the risk of sudden infant death syndrome

The effects of a lack of maternal social support and stressful life events on the risk of Sudden Infant Death Syndrome (SIDS) were examined by case-control design: 390 cases and 1592 control infants. A seven item index of mother's social support was used. A possible 21 life events experienced by each family were summed and then put into one of three categories: 0-2, 3-5, and 6 or more life events. Similar levels of maternal social support were found for both groups. SIDS families experienced significantly more stressful life events than control families, but once social factors had been taken into account this association was lost.

Hemodynamic effects of N-acetylamrinone in a porcine model of group B streptococcal sepsis

High plasma concentrations of N-acetylamrinone, a primary metabolite of amrinone, are measured in some children during prolonged amrinone infusion. The purpose of this investigation was to determine if N-acetylamrinone has direct hemodynamic effects independent of amrinone. Twenty neonatal piglets received an infusion of 6 x 10(9) colony-forming units/kg of group B Streptococcus to induce sepsis. Subsequently, they were divided into 1 of 3 groups and received a 1-hr infusion of either normal saline (N = 4); 8 mg/kg amrinone, followed by 20 micrograms/kg/min (N = 9); or 8 mg/kg N-acetylamrinone, followed by 20 micrograms/kg/min (N = 7). Hemodynamic measurements and arterial/venous blood-gas determinations were obtained every 30 min during the study. Systemic vascular resistance and pulmonary vascular resistance were calculated. One milliliter of blood was obtained every 30 min during drug administration to determine plasma amrinone and N-acetylamrinone concentrations. The mean amrinone plasma concentrations measured at 30 and 60 min during the infusion time in the group receiving amrinone were 8.8 +/- 1.1 and 6.9 +/- 0.7 micrograms/ml, respectively. These animals experienced a significant decrease in mean pulmonary artery pressure and pulmonary vascular resistance, compared with saline controls after a 30-min infusion of amrinone. The mean N-acetylamrinone plasma concentrations measured at 30 and 60 min during the N-acetylamrinone infusion were 7.3 +/- 0.8 and 5.7 +/- 0.6 micrograms/ml, respectively. There was no difference between any hemodynamic parameter measured in these animals, compared with saline controls at any time during the infusion. We conclude that amrinone, but not N-acetylamrinone, causes pulmonary vasodilation in a porcine model of sepsis and that the parent drug is the sole active component in amrinone.

HPLC micromethod for amrinone and metabolites in patients receiving concurrent cephalosporin therapy

Amrinone (AMR), a bipyridine derivative, is receiving increasing use in postoperative cardiac patients as an inotrope and vasodilator. The hemodynamic response to amrinone in adults is linearly related to AMR concentrations, warranting therapeutic drug monitoring. We report a rapid microsample HPLC method for monitoring AMR and its principal metabolites, N-acetyl (N-ac) and N-glycolyl (N-gly) AMR. Serum was precipitated with acetonitrile, and the supernatant fluid was then injected into a C18 narrow-bore column. The mobile phase consisted of a 0.1 mol/L sodium phosphate buffer (pH 6) with a gradient of acetonitrile going from 50 to 100 mL/L of eluent. Detection with a diode-array detector (DAD) concurrently monitored the absorbances at 320 and 345 nm. Monitoring 320 nm allows optimal quantification of AMR, N-gly, and N-ac. Patients often receive concurrent cephalosporin therapy, which is detectable at 320 nm but not 345 nm. Because cephalosporins coelute with AMR or metabolites, monitoring at 345 nm allows separation of these antibiotics from AMR and metabolites while retaining a detection limit of 0.5 mg/L.

HPLC micromethod for amrinone and metabolites in patients receiving concurrent cephalosporin therapy

Amrinone (AMR), a bipyridine derivative, is receiving increasing use in postoperative cardiac patients as an inotrope and vasodilator. The hemodynamic response to amrinone in adults is linearly related to AMR concentrations, warranting therapeutic drug monitoring. We report a rapid microsample HPLC method for monitoring AMR and its principal metabolites, N-acetyl (N-ac) and N-glycolyl (N-gly) AMR. Serum was precipitated with acetonitrile, and the supernatant fluid was then injected into a C18 narrow-bore column. The mobile phase consisted of a 0.1 mol/L sodium phosphate buffer (pH 6) with a gradient of acetonitrile going from 50 to 100 mL/L of eluent. Detection with a diode-array detector (DAD) concurrently monitored the absorbances at 320 and 345 nm. Monitoring 320 nm allows optimal quantification of AMR, N-gly, and N-ac. Patients often receive concurrent cephalosporin therapy, which is detectable at 320 nm but not 345 nm. Because cephalosporins coelute with AMR or metabolites, monitoring at 345 nm allows separation of these antibiotics from AMR and metabolites while retaining a detection limit of 0.5 mg/L.

The pathogenicity of spontaneously-occurring thyroglobulin-reactive T lymphocytes from BB/WOR rats

Autoantigen-reactive T lymphocytes have been implicated in the pathogenesis organ-specific autoimmune disease. Thyroglobulin (Tg) is one of the primary autoantigens associated with autoimmune lymphocytic thyroiditis (LT). These experiments investigated the pathogenicity of a lymphocyte line derived from spontaneously-occurring Tg-reactive T lymphocytes isolated from unprimed NB line BB/Wor rats which have nearly a 100% incidence of spontaneous LT. Adoptive transfer of LT was accomplished by injecting 1.0 x 10(5) Tg-reactive lymphocytes into the tail vein of MHC compatible, non LT-prone BB line BB/Wor rats. All of the Tg-reactive cell line recipients (5/5) developed LT compared to only 20% (1/5) of the control rats given a parallel tetanus toxoid-reactive T cell line (p < 0.05, Fisher's exact test). Furthermore, despite the presence of LT, only one Tg-reactive cell line recipient developed insulitis. When Tg-reactive lymphocytes were incubated with an MHC compatible Wistar rat thyrocyte line at increasing effector: target ratios, the T cell line lysed thyrocytes in a dose-response fashion (r = 0.99, p < 0.05, linear regression), but did not lyse smooth muscle cell targets. FACS analysis established that this cell line is CD8 predominant. This is the first study to demonstrate that spontaneously-occurring Tg-reactive T lymphocytes from a nonimmunized animal model for LT are pathogenic. Further investigations into the repertoire of Tg-reactive lymphocytes in BB/Wor rats should provide insight into the pathogenesis of autoimmune thyroid disease and provide a basis for targeted immunotherapy.

Difference between the measured and ordered dose of catecholamine infusions

OBJECTIVE

To measure the actual concentrations of dopamine, dobutamine, and epinephrine in infusates prepared for patients, and to compare these concentrations with those of the dopamine HCl, dobutamine, and epinephrine HCl infusates that had been prescribed to evaluate drug preparation accuracy.

DESIGN

Prospective, unblind study.

SETTING

Pediatric intensive care unit in a tertiary-care teaching hospital.

PARTICIPANTS

All dopamine, dobutamine, and epinephrine infusions ordered for patients during the 2-month study period were eligible for inclusion in the study.

MEASUREMENTS

Daily samples of dopamine, dobutamine, and epinephrine infusates that were prepared for 41 pediatric patients were obtained; the infusate catecholamine concentration was measured by HPLC and compared with the ordered concentration. The concentration than was multiplied by the rate of infusion to determine the catecholamine dose.

MAIN RESULTS

There were significant differences between the measured doses of dopamine, dobutamine, and epinephrine and the dopamine HCl, dobutamine, and epinephrine HCl doses (p = 0.0001, p = 0.039, and p = 0.0009, respectively) that had been ordered because of preparation inaccuracies. Failure to account for the HCl salt in the stock drug accounted for some, but not all, of the inaccuracy of the dopamine HCl and epinephrine HCl infusates. There was a wide interday variability in the measured catecholamine dosage in patients receiving the same dose for 3 days or more.

CONCLUSIONS

There are daily fluctuations in the preparation of dopamine, dobutamine, and epinephrine infusates that could alter the amount of drug actually delivered to critically ill patients and potentially contribute to their hemodynamic instability.

Antenatal and intrapartum factors associated with sudden infant death syndrome in the New Zealand Cot Death Study

OBJECTIVE

To describe the relationship between antenatal and intrapartum factors and sudden infant death syndrome (SIDS).

METHODOLOGY

The New Zealand Cot Death Study was a 3 year case-control study, with 485 infants who died from SIDS in the postneonatal period and 1800 randomly selected control infants. Data were obtained from obstetric records, parental interview and community nursing records.

RESULTS

This study confirms many of the antenatal and intrapartum risk factors for SIDS noted in studies from both the southern and northern hemispheres. After controlling for potential confounders, such as occupational group and marital status, significant inverse effects were noted for interpregnancy interval, birthweight and gestation. Other factors that retained a significantly increased risk of SIDS were: increasing parity, bacteriological evidence of urinary tract infection (UTI) (adjusted odds ratio 1.73, 95% CI 1.10-2.73); smoking antenatally (AdjOR 2.14, 95% CI 1.61-2.84); less than six antenatal checks attended (AdjOR 1.84, 95% CI 1.19-2.84); second stage of labour less than 16 min (AdjOR 2.06, 95% CI 1.35-3.14) and multiple birth (AdjOR 3.23, 95% CI 1.70-6.02). No interaction was observed between maternal haemoglobin and antenatal smoking. Interactions were tested for and not found between antenatal smoking and three antenatal risk factors (UTI, short second stage of labour and number of antenatal appointments). The only significant interaction between these three factors and three modifiable postnatal risk factors (prone sleeping, bed sharing and bottle feeding) was between bed sharing and fewer antenatal appointments. The risk of SIDS associated with bed sharing was greater among those whose mothers had fewer antenatal appointments.

CONCLUSIONS

Although many of the previously identified antenatal and intrapartum risk factors for SIDS are confirmed, the risks of SIDS associated with obstetric factors are in general considerably lower than the risks associated with the four modifiable postnatal risk factors.

Oral dimercaptosuccinic acid and ongoing exposure to lead: effects on heme synthesis and lead distribution in a rat model

Lead (Pb) exposure and subsequent toxicity continues to be a significant problem in the United States. Treatment with meso-2,3-dimercaptosuccinic acid (DMSA) has been reported to be effective in reducing the body's Pb burden, with fewer adverse side effects than other chelating agents. The oral availability and relative safety of DMSA presents the controversial option of treating patients with Pb poisoning on an outpatient basis. Despite recommendations that children be removed from the Pb contaminated environment, some children will inevitably be exposed to environmental Pb while receiving oral DMSA therapy. The study hypothesized that oral DMSA chelation therapy is beneficial even when faced with continued dietary Pb. Sprague-Dawley rats were exposed to Pb in water for 35 days and then placed in various treatment groups, including groups administered oral DMSA with and without concurrent Pb exposure. The concentration of Pb in blood and critical organs and Pb diuresis were measured. The effect of Pb on heme synthesis was determined by assaying the urinary delta-aminolevulinic acid (delta-ALA), and blood zinc protoporphyrin (ZPP). DMSA reversed the hematological effects of Pb, decreased the blood, brain, bone, kidney, and liver Pb concentration, and produced a marked Pb diuresis, even when challenged with ongoing Pb exposure. In conclusion, even though DMSA treatment without exposure to Pb is optimal, oral DMSA could be beneficial even when challenged with ongoing Pb exposure.

Thyroglobulin-reactive T lymphocytes in thyroiditis-prone BB/Wor rats

Autoimmune lymphocytic thyroiditis (LT) is a common cause of primary hypothyroidism. Autoreactive T lymphocytes are clearly associated with this disorder, but their pathogenic role in spontaneously occurring LT remains to be established. In the present study, thyroglobulin-reactive T lymphocytes were cultured from young, unprimed LT-prone BB/Wor rats before the age of spontaneously-occurring LT. Although similar investigations have been conducted in animal models for experimental autoimmune thyroiditis (EAT), this study is unique because it examines a mammalian model for spontaneous LT. Splenic T lymphocytes were isolated from unprimed 30 to 45-day-old Fisher and LT-prone BB/Wor rats before the onset of LT, then tested for activation by normal (NL), iodine-poor (LI), and iodine-rich (HI) rat thyroglobulin (Tg) in bulk proliferation assay. BB/Wor rat lymphocytes were activated by all three Tg preparations, but Fisher lymphocytes were unresponsive (BB/Wor vs Fisher; p < 0.0001, Student's t-test). There was no difference between BB/Wor rat responses to the three preparations (p > 0.05, ANOVA). Based on these results, we conclude that Tg-responsive T lymphocytes can be cultured from young, unprimed LT-prone BB/Wor rats. Isolating such lymphocytes before the onset of histologically demonstrable LT strengthens the argument that antigen-specific T cells have a pathogenic role in the development of spontaneous autoimmune thyroid disease. The fact that these lymphocytes recognized normal, iodine-rich and iodine poor preparations of rat Tg equally well suggest that unlike the EAT model, spontaneously-occurring Tg-reactive T cells are not influenced by thyroglobulin's iodine content.

Factors adversely associated with breast feeding in New Zealand

Control data from 1529 infants studied in a multicentre case-control study of sudden infant death in New Zealand were analysed to identify factors that might hinder the establishment and duration of breast feeding. Although 1300 infants (85%) were exclusively breast-fed at discharge from the obstetric hospital, this fell to 940 (61%) by 4 weeks. Logistic regression was used to identify factors that might adversely influence breast feeding 'at discharge', 'at 4 weeks' and the overall 'duration' of breast feeding. When adjusted for confounding factors, not exclusive breast feeding 'at discharge' was significantly associated with: twin pregnancy, being a Pacific Islander, mother not bedsharing, subsequent dummy use, birthweight less than 2500 g, heavy maternal smoking, not attending antenatal classes and mother less than 20 years old at first pregnancy. Mothers smoking more than 20 cigarettes a day were nearly twice as likely to not exclusively breast feed on discharge compared to those who did not smoke. A 'dose response' was apparent with the heaviest smokers having the least likelihood of establishing exclusive breast feeding. Being exclusively breast-fed at discharge but not 'at 4 weeks' was associated with: twin pregnancy, admission to a neonatal intensive care unit, subsequent dummy use and not being married. A shorter overall 'duration' of breast feeding was associated with maternal smoking, subsequent dummy use, mother not bedsharing, twin pregnancy, mother less than 20 years old at first pregnancy, low occupational status and not attending antenatal classes. These effects persisted when social and demographic factors, including birthweight, were taken into account.(ABSTRACT TRUNCATED AT 250 WORDS)

Lithium sustains the acute antidepressant effects of sleep deprivation: preliminary findings from a controlled study

Early morning sleep deprivation (patient awake from 0200 to 2200 hours) produces a same-day antidepressant effect in approximately one-half of patients with major depression. Unfortunately, these antidepressant effects are short-lived and patients usually relapse to baseline depression levels within 48 hours. Recent work suggests, however, that the use of lithium with early morning sleep deprivation sustains this rapid antidepressant effect and makes it clinically useful. In a 30-day study, we compared the abilities of four different treatments (lithium plus early morning sleep deprivation, lithium plus a control sleep deprivation procedure, and desipramine with either of the two sleep manipulations) to induce a rapid (next-day) and sustained antidepressant response in 16 depressed patients. Lithium plus early morning sleep deprivation produced a quicker response than lithium with the control sleep deprivation, and the response was sustained for at least 30 days. In this design, however, lithium/early morning sleep deprivation was no faster than either of the two desipramine/sleep deprivation conditions in inducing remission. These results support the results of previous studies and suggest further investigation of this novel sleep/pharmacologic intervention is warranted.

Bed sharing, smoking, and alcohol in the sudden infant death syndrome. New Zealand Cot Death Study Group

OBJECTIVES

To investigate why sharing the bed with an infant is a not consistent risk factor for the sudden infant death syndrome in ethnic subgroups in New Zealand and to see if the risk of sudden infant death associated with this practice is related to other factors, particularly maternal smoking and alcohol consumption.

DESIGN

Nationwide case-control study.

SETTING

Region of New Zealand with 78% of all births during 1987-90.

SUBJECTS

Home interviews were completed with parents of 393 (81.0% of total) infants who died from the sudden infant death syndrome in the postneonatal age group, and 1592 (88.4% of total) controls who were a representative sample of all hospital births in the study region.

RESULTS

Maternal smoking interacted with infant bed sharing on the risk of sudden infant death. Compared with infants not exposed to either risk factor, the relative risk for infants of mothers who smoked was 3.94 (95% confidence interval 2.47 to 6.27) for bed sharing in the last two weeks and 4.55 (2.63 to 7.88) for bed sharing in the last sleep, after other confounders were controlled for. The results for infants of non-smoking mothers were inconsistent with the relative risk being significantly increased for usual bed sharing in the last two weeks (1.73; 1.11 to 2.70) but not for bed sharing in the last sleep (0.98; 0.44 to 2.18). Neither maternal alcohol consumption nor the thermal resistance of the infant's clothing and bedding interacted with bed sharing to increase the risk of sudden infant death, and alcohol was not a risk factor by itself.

CONCLUSION

Infant bed sharing is associated with a significantly raised risk of the sudden infant death syndrome, particularly among infants of mothers who smoke. The interaction between maternal smoking and bed sharing suggests that a mechanism involving passive smoking, rather than the previously proposed mechanisms of overlaying and hyperthermia, increases the risk of sudden infant death from bed sharing.

Breastfeeding and the risk of sudden infant death syndrome

The New Zealand Cot Death Study, a multicentre case-control study, was set up to identify risk factors associated with sudden infant death syndrome (SIDS). In the 3 years of the study there were 485 infant deaths classified as SIDS in the study areas and 1800 infants who were randomly selected as controls. Data were collected by parent interviews and from obstetric notes. A full set of data for this analysis was available from 356 cases and 1529 control infants. The relationship between length of any breastfeeding and SIDS was examined: 92% of the controls were initially breastfed compared to 86% of the cases. As time went by, cases stopped breastfeeding sooner than controls: by 13 weeks, 67% controls were breastfed versus 49% cases. A reduced risk for SIDS in breastfed infants persisted during the first 6 months after controlling for confounding demographic, maternal and infant factors. Infants exclusively breastfed 'at discharge from the obstetric hospital' (odds ratio [OR] = 0.52, 95% confidence interval (CI): 0.35-0.71) and during the last 2 days (OR = 0.65, 95% CI: 0.46-0.91) had a significantly lower risk of SIDS than infants not breastfed after controlling for potential confounders. We have shown a substantial association of breastfeeding with a lowered risk for SIDS. This supports the need for more positive promotion and active community support to further enhance the level and length of exclusive breastfeeding.

Subclass reactivity of pemphigus foliaceus autoantibodies with recombinant human desmoglein

Pemphigus foliaceus (PF) and its endemic form, Fogo Selvagem (FS), are autoimmune disorders characterized by subcorneal vesicles and IgG4 subclass autoantibodies that recognize a surface antigen of normal epidermal cells. FS and PF autoantibodies have been shown to bind desmoglein (DGI), a desmosomal glycoprotein classified as a member of the cadherin family of calcium-dependent cell adhesion molecules. In the present study we report the isolation of three overlapping cDNA clones representing greater than 90% of the extracellular domain of human DGI. Recombinant proteins encoded by these clones, designated DGI-1, DGI-2, and DGI-3, were produced in bacteria and analyzed for immunoblot (IB) reactivity with a panel of FS, PF, and control sera. FS and PF autoantibodies possessing reactivity with each of the three recombinant fusion proteins (FPs) were identified. FP DGI-3 (containing 123 amino acids of the membrane proximal region of the DGI ectodomain) showed reactivity with the largest number of patient sera--seven FS and one PF. IB reactivity with the DGI-1 FP (encoding 205 amino acids of the N-terminal region of DGI) could be eliminated by truncation of the C-terminal portion of this protein, indicating that autoantibodies were not binding the R-A-L motif. Autoantibodies reactive with two of the three FPs were predominantly restricted to IgG4, the subclass shown to be pathogenic in the passive transfer mouse model. The findings of this study demonstrate that the extracellular domain of DGI contains at least three antigenic sites recognized by FS and PF autoantibodies. The region near the membrane-spanning domain of DGI appears to contain an immunodominant site. This study is the first to document immunoblot reactivity of FS and PF autoantibodies with recombinant forms of DGI. The use of such molecular tools should facilitate the identification and characterization of relevant antigen/antibody systems in FS and PF.

Smoking and the sudden infant death syndrome

OBJECTIVE

Maternal smoking has been shown to be a risk factor for sudden infant death syndrome (SIDS). The effect of smoking by the father and other household members has not previously been examined.

METHODS

A large nationwide case-control study. Four hundred eighty-five SIDS deaths in the postneonatal age group were compared with 1800 control infants.

RESULTS

Infants of mothers who smoked during pregnancy had a 4.09 (95% confidence interval [CI] = 3.28, 5.11) greater risk of death than infants of mothers who did not smoke. Infants of mothers who smoked postnatally also had an increased risk of SIDS compared with infants of nonsmokers and, furthermore, the risk increased with increasing levels of maternal smoking. Smoking by the father and other household members increased the risk (odds ratio [OR] = 2.41, 95% CI = 1.92, 3.02 and OR = 1.54, 95% CI = 1.20, 1.99, respectively). Smoking by the father increased the risk of SIDS if the mother smoked, but had no effect if she did not smoke. In analyses controlled for a wide range of potential confounders, smoking by the mother and father was still significantly associated with an increased risk of SIDS.

CONCLUSION

Passive tobacco smoking is causally related to SIDS.

Acute iodine ingestion increases intrathyroidal glutathione

In genetically predisposed individuals, autoimmune lymphocytic thyroiditis (LT) is potentiated by excess dietary iodine (I). There have been data which suggest that oxidative stress may have a role in iodine-induced LT. These in vivo studies were undertaken to examine the effect of iodine on intrathyroidal levels of the potent antioxidant glutathione (GSH) and see if the thyroids of LT-prone BB/Wor rats have aberrant GSH responses after iodine-loading. LT-prone BB/Wor, non LT-prone BB/Wor and Wistar rats were randomized to receive either 0.05% I (as Nal) or tap water. Thyroid and liver homogenates were assayed individually for GSH. Following the administration of 0.05% iodine water overnight, all of the animals demonstrated a rise in intrathyroidal GSH regardless of LT-proneness. To determine whether this was a dose-dependent response, Wis rats were randomized to receive tap, 0.0125%, 0.025%, 0.05%, or 0.075% I, overnight. Intrathyroidal GSH levels rose with increasing iodine concentrations peaking at 0.025% I. Hepatic GSH levels were unaltered by iodine treatment. Ten days of 0.05% I water did not result in any difference between the GSH levels of thyroids from treated and control rats. Frozen sections of the thyroids and livers from iodine-treated rats were compared to tap-water controls after staining with Mercury Orange for GSH and Schiff's reagent for evidence of lipid peroxidation. Iodine-treated thyroids had an apparent shift of GSH staining from the apical border to the cytoplasm. However, there was no Schiff's staining indicative of lipid peroxidation in the iodine-treated thyroids.(ABSTRACT TRUNCATED AT 250 WORDS)

Dummies and the sudden infant death syndrome

The association between dummy use and sudden infant death syndrome (SIDS) was investigated in 485 deaths due to SIDS in the postneonatal age group and compared with 1800 control infants. Parental interviews were completed in 87% of subjects. The prevalence of dummy use in New Zealand is low and varies within New Zealand. Dummy use in the two week period before death was less in cases of SIDS than in the last two weeks for controls (odds ratio (OR) 0.76, 95% confidence interval (CI) 0.57 to 1.02). Use of a dummy in the last sleep for cases of SIDS or in the nominated sleep for controls was significantly less in cases than controls (OR 0.44, 95% CI 0.26 to 0.73). The OR changed very little after controlling for a wide range of potential confounders. It is concluded that dummy use may protect against SIDS, but this observation needs to be repeated before dummies can be recommended for this purpose. If dummy sucking is protective then it is one of several factors that may explain the higher mortality from SIDS in New Zealand than in other countries, and may also explain in part the regional variation within New Zealand.

Ethnic differences in mortality from sudden infant death syndrome in New Zealand

OBJECTIVES

To examine the factors which might explain the higher mortality from sudden infant death syndrome in Maori infants (7.4/1000 live births in 1986 compared with 3.6 in non-Maori children).

DESIGN

A large nationwide case control study.

SETTING

New Zealand. 485 infants who died of sudden infant death syndrome were compared with 1800 control infants. There were 229 Maori and 240 non-Maori cases of sudden infant death syndrome (16 cases unassigned) and 353 Maori and 1410 non-Maori controls (37 unassigned).

RESULTS

Maori infants had 3.81 times the risk (95% confidence interval 3.06 to 4.76) of sudden infant death syndrome compared with non-Maori infants. The risk factors for sudden infant death syndrome within groups were remarkably similar. When Maori and non-Maori controls were compared the prevalence of many of the known risk factors was higher in Maori infants. In particular, mothers were socioeconomically disadvantaged, younger, and more likely to smoke and their infants were of lower birth weight and more likely to share a bed with another person. Multivariate analysis controlling for potential confounders found that simply being Maori increased the risk of sudden infant death syndrome by only 1.37 (95% CI = 0.95 to 2.01), not statistically significantly different from 1. Population attributable risk was calculated for prone sleeping position, maternal smoking, not breast feeding, and infants sharing a bed with another person. In total these four risk factors accounted for 89% of deaths from sudden infant death syndrome in Maori infants and 79% in non-Maori infants.

CONCLUSION

The high rate of sudden infant death syndrome among Maori infants is based largely on the high prevalence in the Maori population of the major risk factors. Other risk factors, not related to ethnicity, probably explain remaining differences between Maori and non-Maori children.

Pilot study of computerised differentiation of Huntington's disease, schizophrenic, and Parkinson's disease patients using the contingent negative variation

In this study a potential known as the contingent negative variation was used to differentiate between schizophrenic, Parkinson's disease (PD), Huntington's disease (HD) patients and normal control subjects. The aim was to assist diagnosis and the avoidance of false diagnosis. 20 schizophrenic, 16 PD, 11 HD and 43 normal control subjects were enrolled for this study. The discriminatory variables were generated by applying spectral analysis to pre- and post-stimulus sections of the CNV responses. The patient differentiation was achieved by using the measured variables in a discriminant analysis program. It was possible to accurately differentiate between HD, schizophrenic, PD patients and normal control subjects. It was also attempted to differentiate between HD and schizophrenic patients, HD and PD patients, and schizophrenic and PD patients. The test results indicated that the method is useful in differentiating between these patients. This study had a number of limitations. It was based on a limited number of individuals, and an analysis of medication effects on the test results and the test-retest reliability assessment could not be carried out.

The effect of iodine on lipid peroxidation and ultrastructure in the thyroids of BB/Wor rats

There has been recent data suggesting that iodine potentiates lymphocytic thyroiditis (LT) by inciting oxidative stress. However, the mechanism by which iodine induces LT in genetically predisposed animals is unknown. This study was undertaken to examine LT-prone BB/Wor (LT-P) rat thyroids for signs of acute iodine toxicity and oxidative damage before the onset of spontaneous LT. Lipid peroxidation was assessed by the measurement of malonyldialdehyde (MDA) in thyroid homogenates after randomization to a treatment group receiving 0.05% iodide in the drinking water or tap water for 24 hours. Basal MDA levels were higher in LT-prone rat thyroids than Wistar rat thyroids, but iodine treatment did not influence intrathyroidal MDA levels. Electronmicroscopy demonstrated that prolonged treatment with excess iodine, increased the number of apical lysosomes. But there were no ultrastructural changes unique to LT-P rat thyroids. These data suggest that although LT-P rat thyroids may experience subclinical oxidative damage before the onset of histologically demonstrable LT, this activity is not affected by iodine.

Disruption of social circadian rhythms in major depression: a preliminary report

While dysregulations of physiological circadian rhythms are common findings in depression and have been posited to be involved in the mediation of depressive episodes, only recently has the role of social circadian rhythms in the pathogenesis of depression been a focus of interest. The Social Rhythm Metric (SRM), designed to describe the regularity of a human subject's social circadian rhythms, was used in this study to compare the social rhythms of depressed patients with those of normal controls and to determine the relationship between SRM scores and depression severity. Depressed patients' SRM scores were significantly lower than those of normal controls. The SRM negatively correlated with scores on the Hamilton Rating Scale for Depression. Overall social activity was negatively correlated with a Hamilton item, social activity impairment. The results of this preliminary study support the hypothesis that social zeitgebers are disrupted in major depression.

Postnatal depression and SIDS: a prospective study

This study was carried out in response to reports from nurses to a post-neonatal mortality review committee that a number of mothers of infants dying from sudden infant death syndrome (SIDS) appeared to be depressed before the child's death. The New Zealand Cot Death Study was a 3 year multicentre case-control study for SIDS. There were 485 SIDS cases in the post-neonatal age group in the study regions, and these were compared with 1800 control infants. Infants of mothers with either a self-reported use of medication for psychiatric disorders, a history of hospitalization for psychiatric illness or a family history of postnatal depression had a significantly increased risk of SIDS compared with infants of mothers who were either not using medication (odds ratio (OR) = 1.45; 95% confidence interval (CI) = 1.03, 2.04) or were without a history of hospitalization for psychiatric illness (OR = 1.80; 95% CI = 1.03, 3.11) or a family history of postnatal depression (OR = 1.61; 95% CI = 1.06, 2.43). All mothers of infants born in the study areas over a 1 year period were eligible to complete a questionnaire measuring maternal depression when the infant was 4 weeks of age. Thirty-three infants subsequently died from SIDS, and they were compared with 174 controls. Fifteen (45.5%) of the mothers of cases were depressed, compared with 28 (16.1%) of the mothers of controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Four modifiable and other major risk factors for cot death: the New Zealand study

New Zealand's high mortality rate from sudden infant death syndrome (SIDS) prompted the development of the New Zealand Cot Death Study. A report of the analysis of the data from the first year has been published. This report now gives the major identified risk factors from the full 3 year data set. In this case-control study there were 485 infants who died from SIDS in the post-neonatal age group, and 1800 control infants, who were a representative sample of all hospital births in the study region. Obstetric records were examined and parental interviews were completed in 97.5% and 86.9% of subjects, respectively. As expected many risk factors for SIDS were confirmed including: lower socio-economic status, unmarried mother, young mother, younger school-leaving age of mother, younger age of mother at first pregnancy, late attendance at antenatal clinic, non-attendance at antenatal classes, Maori, greater number of previous pregnancies, the further south the domicile, winter, low birthweight, short gestation, male infant and admission to a special care baby unit. In addition, however, we identified four risk factors that are potentially amenable to modification.(ABSTRACT TRUNCATED AT 250 WORDS)

The New Zealand Cot Death Study: some legal and ethical issues

The New Zealand Cot Death Study is a 3 year multicentre case-control study aimed at identifying the risk factors for sudden infant death syndrome (SIDS). The paper describes some of the legal and ethical issues which arose in the planning, implementation and analysis of the study.

Further evidence supporting a causal relationship between prone sleeping position and SIDS

A 3 year case-control study identifying the risk factors for SIDS was undertaken. Preliminary analysis of the data from the first year suggested that SIDS mortality could fall by 50% if the prevalence of the prone sleeping position changed from 40 to 0%. During the 3 year study the prevalence of the prone sleeping position among infants has fallen from 43% in the first year to 20% in the third year. SIDS mortality has fallen to 3.1/1000 live births, which is very close to that predicted. When considered with other available evidence this strongly supports a causal relationship between the prone sleeping position and SIDS.

Management of nutritional and infectious complications of postoperative chylothorax in children

Postoperative chylothorax may occur following any intrathoracic surgical procedure in children. From January 1979 through February 1987, 18 children aged 1 month to 9 years had chylothorax listed among their discharge diagnoses. Initial therapy for all patients consisted of chest tube placement for pleural space drainage and nutritional support with either enteral formulas enriched with medium-chain triglycerides or total parenteral nutrition. Both total parenteral nutrition and medium-chain triglyceride-enriched enteral regimens provided adequate nutritional support in these children. Five of the 18 experienced lymphopenia secondary to chylous lymphocyte loss. Infections were diagnosed in 5 patients during hospitalization; one was a fatal viral pneumonitis. No correlation between infectious complications and lymphocyte count could be demonstrated.

Herpes simplex virus type 1-specific cytotoxic T lymphocytes recognize immediate-early protein ICP27

The identity of herpes simplex virus type 1 (HSV-1) antigens that serve as targets for cytotoxic T lymphocytes (CTL) and their ability to induce protective immunity remain uncertain. In this article, we report the identification of the immediate-early protein ICP27 as a CTL antigen in H-2d mice but not in H-2k or H-2b mice. Calculation of the frequencies of H-2d-restricted virus-specific CTL demonstrated that approximately one-fourth of the total HSV-1-specific response was directed against ICP27. To define the location of this CTL epitope, four truncated derivatives of the ICP27 gene which place the epitope in a 217-amino-acid region (amino acids 189 to 406) near the central portion of the protein were constructed. Mice immunized with ICP27 were able both to induce HSV-1-specific CTL and to survive a lethal intraperitoneal challenge with virulent HSV-1. However, neither appreciable antibody nor delayed-type hypersensitivity responses were induced in immunized mice, and they were also unable to clear a local epithelial virus challenge. It appears that ICP27, although capable of inducing several aspects of the immune response, is by itself unable to provide complete immunity.

Results from the first year of the New Zealand cot death study

New Zealand's high mortality rate from the sudden infant death syndrome (SIDS) prompted the development of the New Zealand cot death study. This report of the preliminary analysis of the first year of the data gives the major identified risk factors. One hundred and sixty-two infants who died from SIDS were compared with 589 control infants, who were a representative sample of all hospital births in the study region. Obstetric records were examined and parental interviews were completed in 96% and 89% of subjects respectively. Data were available for all the variables in this study in 95% of those interviewed, thus 128 cases and 503 controls make up the subjects of this report. As expected we confirmed many risk factors for SIDS including: lower socioeconomic status, unmarried mother, young mother, younger school leaving age of mother, younger age of mother at first pregnancy, late attendance at antenatal clinic, nonattendant at antenatal classes, Maori, greater number of previous pregnancies, lower birth weight, shorter gestation, male infant, admission to neonatal intensive care unit. In addition, however, we identified three risk factors which are potentially amenable to modification. These were the prone sleeping position of baby (odds ratio = 3.53, 95% confidence interval 2.26, 5.54), maternal smoking (1-9 cigarettes/day OR = 1.87, 95% CI = 0.98, 3.54; 10-19/day OR = 2.64, 95% CI = 1.47, 4.74; 20+/day OR = 5.06, 95% CI = 2.86, 8.95) and breast feeding (OR = 2.93, 95% CI = 1.84, 4.67).(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of iodine on lymphocytic thyroiditis in the thymectomized buffalo rat

Excess iodine has been associated with an increased incidence of lymphocytic thyroiditis (LT) in the BB/W rat, obese strain chicken, and hamster. The spontaneous incidence of LT in the Buffalo (Buf) rat is increased by neonatal thymectomy. In the present study, the effect of combined thymectomy and excess iodine ingestion on the incidence of LT in Buf rats has been examined. Buf rats were thymectomized at 1 day of age and randomized at 4 weeks of age to receive either standard rat chow with tap water (controls), or standard rat chow with 0.05% iodine in the drinking water (iodine group) for 12 weeks. The serum was assayed for TSH, antithyroglobulin antibodies, and iodine. The thyroids were fixed in Bouin's solution and stained with hematoxylin and eosin, and the presence of thyroiditis was determined. Iodine increased the incidence of LT from 31% in the control group to 73% in the iodine-treated group (P less than 0.05). Serum TSH concentrations and levels of thyroglobulin antibodies were significantly higher in the iodine-treated rats, primarily due to the increased incidence of LT and subsequent iodine-induced hypothyroidism. These data suggest that iodine enhances the effect of neonatal thymectomy on LT in Buf rats and support the concept that iodine may play an important role in the expression of LT in predisposed animals.

The effects of charcoal and sorbitol (alone and in combination) on plasma theophylline concentrations after a sustained-release formulation

1. The effects of charcoal and sorbitol, alone and in combination, were investigated in eight healthy female volunteers who received 600 mg slow-release theophylline (two 300 mg capsules). 2. The area under the plasma concentration time curve to 24 h (AUC0-24) after theophylline alone was significantly greater than after both the charcoal and charcoal plus sorbitol phase. 3. Charcoal and charcoal with sorbitol also significantly reduced the maximum plasma theophylline concentration (Tmax) and time to maximum concentration (Cmax). 4. Sorbitol significantly increased Cmax and shortened Tmax. 5. Although sorbitol did not reduce the adsorptive efficacy of charcoal, its use alone may be deleterious in poisoning with sustained-release theophylline products.

Role of coexpression of IL-2 and herpes simplex virus proteins in recombinant vaccinia virus vectors on levels of induced immunity

Vaccinia virus recombinants co-expressing the genes for IL-2 and HSV-1 gC or gD were used to study the potential adjuvant effects of IL-2 on immunity to HSV-1. In addition, constructs were produced which, while expressing IL-2, encoded for reduced levels of HSV-1 gC. Studies with mice revealed that gC and gD could stimulate HSV-1 immunity as measured by neutralizing antibody (NA), lymphoproliferation and viral clearance. IL-2 enhancement of NA and lymphoproliferation was observed only in those groups of mice immunized with the sub-optimal gC construct which co-expressed IL-2. In no instance did the presence of IL-2 augment the ability of mice to clear an epithelial challenge of HSV-1.

Recombinant vaccinia virus expressing the herpes simplex virus type 1 glycoprotein C protects mice against herpes simplex virus challenge

The gene encoding the herpes simplex virus type 1 (HSV-1) glycoprotein C (gC) was isolated and cloned into a vaccinia virus insertion vector, and the resulting vaccinia-gC vector was used to construct a recombinant vaccinia virus that expressed gC (VVgC5). Infection of cells with VVgC5 resulted in cell surface expression of authentic HSV-1 gC. HSV-1 gC-specific neutralizing antibodies were produced in VVgC5-immunized mice, and lymphocytes exhibited an HSV-1-specific proliferation response in vitro following infection. More importantly, VVgC5-immunized mice were resistant to subsequent lethal HSV-1 challenge.

Infundibular metastasis and panhypopituitarism

A patient with no known history of primary neoplasia presented with panhypopituitarism secondary to metastasis. Complete anterior pituitary failure was documented by pituitary reserve testing. However, at autopsy there was extensive carcinomatous invasion of the hypothalamus and infundibulum but no adenohypophyseal involvement. The possibility of metastatic disease should be considered in patients presenting with panhypopituitarism. The literature covering this topic is reviewed.