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Background: Laparoscopic sleeve gastrectomy (LSG) is the most common bariatric surgery performed worldwide. The Titan stapler aims to standardize the sleeve gastrectomy by eliminating inconsistencies and simplifying the procedure., Methods: A retrospective chart review was performed on all patients > 18 years of age undergoing LSG using the Titan. Pre-operative demographics, perioperative findings, and post-operative complications were all abstracted from the MBSAQIP database., Results: A total of 807 LSG have been performed using the latest iteration of the Titan stapler since November 2022. Data from these patients was compared to 3829 patients who underwent LSG using a sequential staple firing technique from September 2016-September 2021. The median age of Titan patients was 42 years (IQR 33-52) compared to 44 years (IQR 35-54) for sequential firing. The median pre-operative BMI was 47.1 (IQR 43.5-52.1) for Titan versus 47.6 (IQR 43.1-53.3) for sequential staple firing. After propensity matching, operative duration was significantly less for the Titan. Titan patients had decreased hospital length of stay, experienced fewer 30-day readmissions, and had less post-operative nausea/vomiting. Post-op bleed rates were similar between the two cohorts. Weight loss at 6 months favored the sequential fire arm, but our preliminary data shows this difference diminishes at 1 year., Conclusions: Here we report our data on patients undergoing LSG using the latest Titan stapler. We show the device is safe, effective, and has resulted in an improvement in length of stay, readmissions, and post-operative nausea/vomiting. We also noted reduced operative time with this technique., (© 2024. The Author(s).)

Objectives This study investigated the effects of a national early retirement reform, which was implemented in 2006 and penalized early retirement, on paid employment and different exit pathways and examined whether these effects differ by gender, income level and health status. Methods This study included all Dutch individuals in paid employment born six months before (control group) and six months after (intervention group) the cut-off date of the reform (1 January 1950) that fiscally penalized early retirement. A regression discontinuity design combined with restricted mean survival time analysis was applied to evaluate the effect of penalizing early retirement on labor force participation from age 60 until workers reached the retirement age of 65 years, while accounting for secular trends around the threshold. Results The intervention group postponed early retirement by 7.41 months [95% confidence interval (CI) 6.11-8.72], and partly replaced this by remaining 4.87 months (95% CI 3.60-6.24) longer in paid employment. Workers born after the threshold, annually earning €25 000-40 000, spent 1.24 months (95% CI 0.31-2.18) more in economic inactivity than those born before. The working months lost to unemployment increased by 1.50 months (95% CI 0.30-2.71) for female workers and 1.99 months (95% CI 0.06-3.92) for workers reporting multiple chronic diseases. Conclusions The national reform successfully prolonged working lives of older workers. However, workers with a middle income, female workers, and workers with chronic diseases were more vulnerable to premature exit from the labor market through unemployment or being without any income or benefit.

Objective Using a novel mediation method that presents unbiased results even in the presence of exposure-mediator interactions, this study estimated the extent to which working conditions and health behaviors contribute to educational inequalities in self-rated health in the workforce. Methods Respondents of the longitudinal Survey of Health, Ageing, and Retirement in Europe (SHARE) in 16 countries were selected, aged 50-64 years, in paid employment at baseline and with information on education and self-rated health (N=15 028). Education, health behaviors [including body mass index (BMI)] and working conditions were measured at baseline and self-rated health at baseline and two-year follow-up. Causal mediation analysis with inverse odds weighting was used to estimate the total effect of education on self-rated health, decomposed into a natural direct effect (NDE) and natural indirect effect (NIE). Results Lower educated workers were more likely to perceive their health as poor than higher educated workers [relative risk (RR) 1.48, 95% confidence interval (CI) 1.37-1.60]. They were also more likely to have unfavorable working conditions and unhealthy behaviors, except for alcohol consumption. When all working conditions were included, the remaining NDE was RR 1.30 (95% CI 1.15-1.44). When BMI and health behaviors were included, the remaining NDE was RR 1.40 (95% CI 1.27-1.54). Working conditions explained 38% and health behaviors and BMI explained 16% of educational inequalities in health. Including all mediators explained 64% of educational inequalities in self-rated health. Conclusions Working conditions and health behaviors explain over half of the educational inequalities in self-rated health. To reduce health inequalities, improving working conditions seems to be more important than introducing health promotion programs in the workforce.

Objective This study investigates the impact of physical workload factors and occupational class on working life expectancy (WLE) and working years lost (WYL) in a sample of older Finnish workers. Methods A 70% random sample of Finns in 2004 was linked to a job exposure matrix for physical workload factors and register information on occupational class and labor market status until 2014. Transitions between being at work, time-restricted work disability, unemployment, economic inactivity, disability retirement, retirement and death were estimated. A multistate Cox regression model with transition-specific covariates was used to estimate the WLE and WYL at age 50 up to 63 years for each occupational class and physical workload factor for men and women (N=415 105). Results At age 50, male and female manual workers had a WLE of 10.13 and 10.14 years, respectively. Among both genders, manual workers had one year shorter WLE at age 50 than upper non-manual employees. This difference was largely attributable to unemployment (men: 0.60, women: 0.66 years) and disability retirement (men: 0.28, women: 0.29 years). Self-employed persons had the highest WLE (11.08 years). Men and women exposed to four or five physical workload factors had about one year lower WLE than non-exposed workers. The difference was primarily attributable to ill-health-related reasons, including disability retirement (men: 0.45 years, women: 0.53 years) and time-restricted work disability (men: 0.23, women: 0.33 years). Conclusions Manual workers and those exposed to physical workload factors had the lowest WLE. The differences in WYL between exposure groups can primarily be explained by ill-health-based exit routes.

Objectives The primary aim of this study was to investigate educational inequalities in health-related exit from paid employment through different pathways in five European regions. A secondary objective was to estimate the proportion of different routes out of paid employment that can be attributed to poor health across educational groups in five European regions. Methods Longitudinal data from 2005 up to 2014 were obtained from the four-year rotating panel of the European Union Statistics on Income and Living Conditions (EU-SILC), including 337 444 persons with 1 056 779 observations from 25 countries. Cox proportional hazards models with censoring for competing events were used to examine associations between health problems and exit from paid employment. The population attributable fraction was calculated to quantify the impact of health problems on labor force exit. Results In all European regions, lower-educated workers had higher risks of leaving paid employment due to disability benefits [relative inequality (RI) 3.3-6.2] and unemployment (RI 1.9-4.5) than those with higher education. The fraction of exit from paid employment that could be attributed to poor health varied between the five European regions among lower-educated persons from 0.06-0.21 and among higher-educated workers from 0.03-0.09. The disadvantaged position of lower-educated persons on the labor market was primarily due to a higher prevalence of poor health. Conclusion In all European regions, educational inequalities exist in health-related exclusion from paid employment. Policy measures are needed to reduce educational inequalities in exit from paid employment due to poor health.

Objective: To assess the relationship between technique and surgical devices on anastomotic and staple-line leaks after laparoscopic Roux-en-Y gastric bypass., Background: Leaks after bariatric surgery remain a major source of morbidity and mortality. The association of surgical technique and devices with leaks after gastric bypass is poorly understood., Setting: Multi-centered study that included teaching and non-teaching hospitals that participate in a statewide consortium for quality improvement using a payer-funded outcome registry., Methods: We analyzed data from the Michigan Bariatric Surgery Collaborative and performed a case-control study comparing patients who sustained a leak with those who did not after primary laparoscopic Roux-en-Y gastric bypass. A total of 71 (.44%) patients with leaks were identified between January 2007 and December 2011. The leak group was matched 1:2 to a control group (nonleak) based on procedure type, age, body mass index, sex, and the year in which the procedure was performed. Technique-specific case characteristics and device-specific factors were assessed by reviewing operative notes from all primary bariatric procedures in our study population., Results: The rate of leak decreased during the study period, and there was a significant downward trend (slope estimate: -.19961%, P = .0372). After performing multivariate analysis, the type of anastomosis (circular stapler, hand-sewn, or linear stapler) and stapler manufacturer were not associated with leaks. The use of buttressing material was associated with a higher rate of leaks (odds ratio: 8.79 [95% confidence interval: 2.49-31.01], P = .0007), whereas the use of fibrin sealant was associated with a lower rate of leaks (odds ratio .11 [95% confidence interval: .03-.41], P = .0013). These findings could not be explained by differences in measures of surgeon performance., Conclusion: Leak rates after laparoscopic gastric bypass have fallen in Michigan despite variations in technique and device utilization. Although the type of anastomosis and stapler manufacturer do not appear to be significantly associated with leaks, it appears that the use of buttressing material was more common in cases in which leaks occurred, whereas the use of fibrin sealant was not. Given the complex interplay of multiple variables that affect surgical outcomes, future studies justifying the benefits of operative devices should be evaluated prospectively in the context of surgeon technique and skill., (Copyright © 2016 American Society for Bariatric Surgery. Published by Elsevier Inc. All rights reserved.)

Background: In 2008, the Realize Band (RB) adopted a precurved design (RB-C). We present 2-year outcomes data from the first multiinstitutional study of RB-C. The objective of this study was to analyze weight loss and safety data from bariatric practices in the United States, including academic, nonacademic, public, and private., Methods: The study included adult RB-C patients with a preoperative body mass index (BMI)≥40 kg/m(2) or >35 kg/m(2) with co-morbidity. Exclusions included RB-C's label contraindications for use. Outcomes parameters were percent excess weight loss (%EWL), BMI change, number and volume of band adjustments, and adverse events., Results: A total of 231 patients met inclusion/exclusion criteria. Of these, 161 had 24-month data available. Mean %EWL was 44.4%±26.9% (P<.0001). BMI decreased from 44.1±5.7 kg/m(2) to 35.3±6.9 kg/m(2) (P<.0001). Percent EWL varied by preoperative BMI (P = .0002), bariatric practice (P<.0001), aftercare frequency (P = .0004), and band fill frequency (P = .0271), but %EWL was not influenced by gender, race, or age (P>.20 each). Adverse events were dysphagia (21.2%), gastroesophageal reflux (21.6%), and vomiting (30.7%). Incidence of pouch dilation, esophageal dilation, and slippage was ≤1%. Revisions (2.2%) were for unbuckled band, tube kinking, slippage, and suspected band leak (1 each). No erosions, explants, or mortality were reported., Conclusion: RB-C appears to be as well tolerated and effective as the first generation RB for weight loss. The near 45% EWL at 2 years is consistent with other high-quality publications on the RB. Preoperative BMI and frequency of postoperative care, including frequency of band fills, influence %EWL. Significant weight loss is achievable with RB-C despite variable postoperative management practices. The low morbidity and the absence of mortality at 24 months reflect positively on the RB-C characteristics., (Copyright © 2013 American Society for Bariatric Surgery. Published by Elsevier Inc. All rights reserved.)

Objective: To evaluate the comparative effectiveness of sleeve gastrectomy (SG), laparoscopic gastric bypass (RYGB), and laparoscopic adjustable gastric banding (LAGB) procedures., Background: Citing limitations of published studies, payers have been reluctant to provide routine coverage for SG for the treatment of morbid obesity., Methods: Using data from an externally audited, statewide clinical registry, we matched 2949 SG patients with equal numbers of RYGB and LAGB patients on 23 baseline characteristics. Outcomes assessed included complications occurring within 30 days, and weight loss, quality of life, and comorbidity remission at 1, 2, and 3 years after bariatric surgery., Results: Matching resulted in cohorts of SG, RYGB, and LAGB patients that were well balanced on baseline characteristics. Overall complication rates among patients undergoing SG (6.3%) were significantly lower than for RYGB (10.0%, P < 0.0001) but higher than for LAGB (2.4%, P < 0.0001). Serious complication rates were similar for SG (2.4%) and RYGB (2.5%, P = 0.736) but higher than for LAGB (1.0%, P < 0.0001). Excess body weight loss at 1 year was 13% lower for SG (60%) than for RYGB (69%, P < 0.0001), but was 77% higher for SG than for LAGB (34%, P < 0.0001). SG was similarly closer to RYGB than LAGB with regard to remission of obesity-related comorbidities., Conclusions: With better weight loss than LAGB and lower complication rates than RYGB, SG is a reasonable choice for the treatment of morbid obesity and should be covered by both public and private payers.

Objective: To evaluate the effectiveness and safety of 3 predominant venous thromboembolism (VTE) prophylaxis strategies among patients undergoing bariatric surgery., Design: Cohort study., Setting: The Michigan Bariatric Surgery Collaborative, a statewide clinical registry and quality improvement program., Patients: Twenty-four thousand seven hundred seventy-seven patients undergoing bariatric surgery between 2007 and 2012., Interventions: Unfractionated heparin preoperatively and postoperatively (UF/UF), UF heparin preoperatively and low-molecular-weight heparin postoperatively (UF/LMW), and LMW heparin preoperatively and postoperatively (LMW/LMW)., Main Outcome Measures: Rates of VTE, hemorrhage, and serious hemorrhage (requiring >4 U of blood products or reoperation) occurring within 30 days of surgery., Results: Overall, adjusted rates of VTE were significantly lower for the LMW/LMW (0.25%; P < .001) and UF/LMW (0.29%; P = .03) treatment groups compared with the UF/UF group (0.68%). While UF/LMW (0.22%; P = .006) and LMW/LMW (0.21%; P < .001) were similarly effective in patients at low risk of VTE (predicted risk <1%), LMW/LMW (1.46%; P = .10) seemed more effective than UF/LMW (2.36%; P = .90) for high-risk (predicted risk ≥1%) patients. There were no significant differences in rates of hemorrhage or serious hemorrhage among the treatment strategies., Conclusion: Low-molecular-weight heparin is more effective than UF heparin for the prevention of postoperative VTE among patients undergoing bariatric surgery and does not increase rates of bleeding.

Background: In 2008, the REALIZE Band (RB) adopted a precurved design (RB-C). The present study is the first multi-institutional report of RB-C outcomes. Our objective was to analyze the 1-year weight loss and safety data from adult RB-C patients treated at multiple U.S. centers (7 typical U.S. bariatric practices, including academic, nonacademic, public, and private practice)., Methods: Patients implanted with the RB-C (preoperative body mass index ≥ 40 kg/m(2) or >35 kg/m(2) with co-morbidity) were recruited. The exclusion criteria included the RB-C label contraindications for use. The outcomes parameters were the percentage of excess weight loss (%EWL), change in body mass index, number and volume of band adjustments, and incidence of complications., Results: Of the 239 patients enrolled in the 2-year study, 158 had 1-year data available for analysis in November 2010. The mean %EWL was 39.2% ± 20.5% (range -7.7 to -116.8, P < .0001). The body mass index decreased from 44.4 ± 5.5 kg/m(2) to 36.4 ± 5.8 kg/m(2) (P < .0001). The variability in the %EWL was significant among the study centers (P < .0001). The average band fill volume at 1 year was 8.0 ± 2.0 mL (range .0-11.1). The total fill volume was >11 mL in 1 patient. No band erosions/migrations, explants, or deaths occurred., Conclusion: RB-C appears to be as safe and effective as the first-generation RB. The near 40% EWL at 1 year was consistent with other high-quality publications of the RB. Good weight loss results are achievable, despite the varying postoperative management practices. The low morbidity and the absence of mortality at 12 months reflect positively on the RB-C characteristics. Our findings suggest that the learning curve, related to the postoperative management of the RB-C, might vary by practice and that a greater frequency and smaller band fills might result in better weight loss at 12 months., (Copyright © 2012 American Society for Metabolic and Bariatric Surgery. Published by Elsevier Inc. All rights reserved.)

In this longitudinal study, the authors investigated individual differences in how families adapt to a child's congenital disorder. Family impact, maternal grief resolution, and child attachment were assessed among 74 mothers and their toddlers with a neurological disorder or disfigurement. Fifty dyads were reevaluated 16 months later. For children with neurological compared with disfigurement diagnoses, there was a greater likelihood of negative impact on family, unresolved maternal grief, and insecure attachment at Time 1. Children classified as secure were significantly more likely to have mothers classified as resolved regarding their reactions to their children's diagnosis. Maternal grief resolution was significantly stable (77%) over time and mediated the relation between type of diagnosis and child security. With time, negative impact of child condition on the family decreased and percentage of children classified as secure increased, suggesting that on average families improved. Results suggest that helping parents come to terms emotionally and cognitively with their child's condition may be a useful focus for intervention., (Copyright 2006 APA, all rights reserved.)

Strand displacement amplification (SDA) is an isothermal nucleic acid amplification method based on the primer-directed nicking activity of a restriction enzyme and the strand displacement activity of an exonuclease-deficient polymerase. Here we describe fluorogenic reporter probes that permit real-time, sequence-specific detection of targets amplified during SDA. The new probes possess the single-strand half of a BsoBI recognition sequence flanked on opposite sides by a fluorophore and a quencher. The probes also contain target-binding sequences located 3' to the BsoBI site. Fluorophore and quencher are maintained in sufficiently close proximity that fluorescence is quenched in the intact single-stranded probe. If target is present during SDA, the probe is converted into a fully double-stranded form and is cleaved by the restriction enzyme BsoBI, which also serves as the nicking agent for SDA. Fluorophore and quencher diffuse apart upon probe cleavage, causing increased fluorescence. Target replication may thus be followed in real time during the SDA reaction. Probe performance may be enhanced by embedding the fluorogenic BsoBI site within the loop of a folded hairpin structure. The new probe designs permit detection of as few as 10 target copies within 30 min in a closed-tube, real-time format, eliminating the possibility of carry-over contamination. The probes may be used to detect RNA targets in SDA mixtures containing reverse transcriptase. Furthermore, a two-color competitive SDA format permits accurate quantification of target levels from the real-time fluorescence data., (Copyright 1999 Academic Press.)

Strand Displacement Amplification (SDA) is an isothermal, in vitro method of amplifying a DNA target sequence prior to detection [Walker et al (1992) Nucleic Acids Res., 20, 1691-1693]. Here we describe a multiplex form of SDA that allows two target sequences and an internal amplification control to be co-amplified by a single pair of primers after common priming sequences are spontaneously appended to the ends of target fragments. Multiplex SDA operates at a single temperature, under the same simple protocol previously developed for single-target SDA. We applied multiplex SDA to co-amplification of a target sequence (IS6110) that is specific to members of the Mycobacterium tuberculosis-complex and a target (16S ribosomal gene) that is common to most clinically relevant species of mycobacteria. Both targets are amplified 10(8)-fold during a 2 hour, single temperature incubation. The relative sensitivity of the system was evaluated across a number of clinically relevant mycobacteria and checked for crossreactivity against organisms that are closely related to mycobacteria.

Strand Displacement Amplification (SDA) is an isothermal, in vitro nucleic acid amplification technique based upon the ability of HincII to nick the unmodified strand of a hemiphosphorothioate form of its recognition site, and the ability of exonuclease deficient klenow (exo- klenow) to extend the 3'-end at the nick and displace the downstream DNA strand. Exponential amplification results from coupling sense and antisense reactions in which strands displaced from a sense reaction serve as target for an antisense reaction and vice versa. In the original design (G. T. Walker, M. C. Little, J. G. Nadeau and D. D. Shank (1992) Proc. Natl. Acad. Sci 89, 392-396), the target DNA sample is first cleaved with a restriction enzyme(s) in order to generate a double-stranded target fragment with defined 5'- and 3'-ends that can then undergo SDA. Although effective, target generation by restriction enzyme cleavage presents a number of practical limitations. We report a new target generation scheme that eliminates the requirement for restriction enzyme cleavage of the target sample prior to amplification. The method exploits the strand displacement activity of exo- klenow to generate target DNA copies with defined 5'- and 3'-ends. The new target generation process occurs at a single temperature (after initial heat denaturation of the double-stranded DNA). The target copies generated by this process are then amplified directly by SDA. The new protocol improves overall amplification efficiency. Amplification efficiency is also enhanced by improved reaction conditions that reduce nonspecific binding of SDA primers. Greater than 10(7)-fold amplification of a genomic sequence from Mycobacterium tuberculosis is achieved in 2 hours at 37 degrees C even in the presence of as much as 10 micrograms of human DNA per 50 microL reaction. The new target generation scheme can also be applied to techniques separate from SDA as a means of conveniently producing double-stranded fragments with 5'- and 3'-sequences modified as desired.

A new immunoassay developed for the detection of respiratory syncytial virus (RSV) makes use of magnetic separation and amplification by a dual-enzyme cascade for signal generation. Magnetic particles are conjugated to monoclonal anti-RSV antibodies through the heterobifunctional crosslinker sulfosuccinimidyl 4-(maleimidomethyl)cyclohexane-1-carboxylate, yielding particles of high specific activity and low background. The dual-enzyme cascade is initiated by activation of a masked inhibitor for the enzyme rabbit liver esterase (RLE) by an alkaline phosphatase-antibody conjugate. The esterase activity is then measured to determine the degree of inhibition and, hence, the amount of specifically labeled antigen. These methods yield an immunoassay which is rapid and sensitive. Formation of the immunometric complex requires only 7 min and the total assay time is 40 min. The limit of detection for RSV fusion protein was found to be 1 ng or 10(-14) mol per test. Pre-clinical evaluation of the assay with 52 clinical specimens (nasal washes or aspirates) gave 96% sensitivity (25/26) and 96% specificity (25/26) with respect to a microtiter ELISA procedure and blocking antibody assay.

Bacteria were isolated from a high percentage of the effusions from patients with otitis media with effusion (OME, serous otitis media). In an attempt to determine if the isolated bacteria were involved in the disease process, we analyzed the serum and effusion of 25 OME patients for the presence of antibacterial antibodies by the indirect immunofluorescence antibody method. Specific antibody activity was detected in 20 of 25 effusions (80%) and 19 of 22 sera (86%). IgG antibodies were the most frequently found class of antibodies in both sera and effusions, but IgA antibodies were detected more frequently in the effusions than in the sera. Hemophilus influenzae, Streptococcus pneumoniae, and diphtheroids were the most frequently isolated organisms, and antibody activity to all bacterial species isolated was detected. The results support the concept that the isolated bacteria are not contaminants but are actively involved in the disease process.

The fluorescent dye ethidium bromide stains Escherichia coli and Staphylococcus aureus in whole blood. The staining is rapid, relatively specific, and does not require fixation of the sample. Furthermore, stained bacteria can be seen microscopically without the need for a final wash to remove unbound dye. By using lysostaphin, an S. aureus-specific lytic enzyme, we have demonstrated that S. aureus can be stained with ethidium bromide even after phagocytosis. After short periods of incubation with the dye (less than 5 min), bacteria, both intracellular and extracellular, were the predominant fluorescent particles. With increasing time of incubation, blood cell components, notably leukocyte nuclei, began to fluoresce.

To investigate the possible role of allergy in otitis media with effusion (OME), the immunoglobulin E (IgE) content of 138 middle ear effusions (MEE) and paired serum samples from patients with chronic otitis media with effusion was determined. The initial 62 paired specimens were assayed for IgE by the radioimmunosorbent test (RIST), while the later 76 paired specimens were assayed for IgE by the paper radioimmunosorbent test (PRIST). When the results obtained by these two techniques were compared, it was noted that the PRIST procedure gave significantly lower IgE values for effusions than the RIST method. When the effusion-to-serum ratios (E/S ratios) were computed from the PRIST data, the E/S ratio was less than one, while RIST data gave an E/S ratio greater than one. The results obtained with the PRIST procedure were confirmed by double antibody radioimmunoassay for IgE. Thus, the PRIST procedure appears to measure the IgE content of MEE more accurately, and the results obtained by this procedure fail to support the concept of allergy as a major causative factor in OME.

Eighty-two bacterial isolates recovered from the middle ear effusions (192) of children with otitis media with effusion (OME) were tested for antibiotic sensitivity. Nearly 50% of all bacteria isolated were found to be resistant to penicillin, and in particular, 61% of the Haemophilus isolates were penicillin-resistant; 48% of the Haemophilus isolates were ampicillin-resistant. In addition, we we compared the bacterial recovery rate from effusions of patients who were receiving antibiotics with those who were not. Among patients who were receiving antibiotics, 33% of the effusions were culture positive, while 82% of the effusions were culture positive in the patients who were not given antibiotics. These results are discussed with respect to the possible role of bacteria in the pathogenesis of OME.

Otitis media was induced in chinchillas by intrabullar injection of type 3 Streptococcus pneumoniae. It was found that the severity of a primary infection was related to the dose of bacteria injected, and animals that had recovered from a primary infection were resistant to reinfection with type 3 S pneumoniae. Middle ear effusions from infected animals contained antibodies to type 3 pneumococcal polysaccharide, whereas the sera of these animals lacked this antibody, suggesting that resistance to reinfectin was due to local immune mechanisms. This idea was tested by immunizing chinchillas by various routes. Animals immunized with formalin-killed type 3 S pneumoniae by intramuscular injection (to stimulate the systemic immune system) or by intranasal inoculation (to stimulate the secretory immune system) were found to be susceptible to infection with type 3 pneumonococcus, while animals immunized by inoculation of bacterial suspension directly into the middle ear were resistant to infection. In addition, we found that ampicillin treatment of a primary infection blocks the development of resistance since antibiotic-treated animals were susceptible to reinfection with the type 3 pneumococcus. These results indicate that chinchillas develop an immunity to pneumococcal otitis media following recovery from primary infection and that this immunity is mediated primarily by local immune mechanisms rather than systemic immune responses.

A quantitative cytologic study of 83 middle ear effusions from children with otitis media with effusion (OME) was made with the use of cytocentrifuge-prepared smears and was correlated with bacteriological findings. The identification of the types of cell present in an effusion was confirmed by electron microscopic findings. The most common cell types were neutrophilic leukocytes, lymphocytes, and macrophages, but a few eosinophils were found in only one case. The cytologic profile of an effusion correlated well with the bacterial culture results. Neutrophil counts were significantly higher in effusions that contained pathogenic bacteria (P less than .01) than in culture-negative effusions. Lymphocytes were the dominant cell type in culture-negative effusions. The results support the idea that bacteria are involved in the pathogenesis of many cases of OME.