Child and adolescent COVID-19 vaccination coverage by educational setting, United States.

OBJECTIVES: The COVID-19 pandemic changed the setting of education for many children in the U.S. Understanding COVID-19 vaccination coverage by educational setting is important for developing targeted messages, increasing parents' confidence in COVID-19 vaccines, and protecting all children from severe effects of COVID-19 infection. STUDY DESIGN/METHODS: Using data from the Household Pulse Survey (n = 25,173) collected from December 9-19, 2022, January 4-16, 2023, and February 1-13, 2023, this study assessed factors associated with COVID-19 vaccination and reasons for non-vaccination among school-aged children 5-11 and adolescents 12-17 by educational setting. RESULTS: Among children 5-11 years, COVID-19 vaccination coverage was higher among those who received in-person instruction (53.7%) compared to those who were homeschooled (32.5%). Furthermore, among adolescents 12-17 years, COVID-19 vaccination coverage was higher among those who received in-person instruction (73.5%) or virtual/online instruction (70.1%) compared to those who were homeschooled (51.0%). Children and adolescents were more likely to be vaccinated if the parental respondent had been vaccinated compared to those who had not. Among children and adolescents who were homeschooled, main reasons for non-vaccination were concern about side effects (45.4-51.6%), lack of trust in COVID-19 vaccines (45.0-50.9%), and lack of trust in the government (32.7-39.2%). CONCLUSIONS: Children and adolescents who were home-schooled during the pandemic had lower vaccination coverage than those who attended school in person, and adolescents who were home-schooled had lower vaccination coverage than those who received virtual instruction. Based on the reasons for non-vaccination identified in this study, increasing parental confidence in vaccines, and reducing barriers to access are important for supporting COVID-19 vaccination for school-age children.

Every child, every day, back to play: the PICUstars protocol - implementation of a nurse-led PICU liberation program.

BACKGROUND: As admissions to paediatric intensive care units (PICU) rise and mortality rates decline, the focus is shifting from survival to quality of survivorship. There is paucity of internationally accepted guidelines to manage complications like over-sedation, delirium, and immobility in the paediatric setting. These have a strong adverse impact on PICU recovery including healthcare costs and long-term functional disability. The A2F bundle (ABCDEF), or ICU Liberation, was developed to operationalise the multiple evidence-based guidelines addressing ICU-related complications and has been shown to improve clinical outcomes and health-care related costs in adult studies. However, there is little data on the effect of ICU Liberation bundle implementation in PICU. METHODS: PICU-STARS will be a single centre before-and-after after trial and implementation study. It is designed to evaluate if the multidimensional, nurse-led ICU Liberation model of care can be applied to the PICU and if it is successful in minimising PICU-related problems in a mixed quaternary PICU. In a prospective baseline measurement, the present practises of care in the PICU will be assessed in order to inform the adaptation and implementation of the PICU Liberation bundle. To assess feasibility, implementation outcomes, and intervention effectiveness, the implementation team will use the Consolidated Framework for Implementation Research (CIFR) and process assessment (mixed methods). The implementation process will be evaluated over time, with focus groups, interviews, questionnaires, and observations used to provide formative feedback. Over time, the barriers and enablers for successful implementation will be analysed, with recommendations based on "lessons learned." All outcomes will be reported using standard descriptive statistics and analytical techniques, with appropriate allowance for patient differentials in severity and relevant characteristics. DISCUSSION: The results will inform the fine-tune of the Liberation bundle adaptation and implementation process. The expected primary output is a detailed adaptation and implementation guideline, including clinical resources (and investment) required, to adopt PICU-STARS in other children's hospitals. PATIENT AND PUBLIC INVOLVEMENT STATEMENT: The authors thank the PICU education and Liberation Implementation team, and our patients and families for their inspiration and valuable comments on protocol drafts. Results will be made available to critical care survivors, their caregivers, relevant societies, and other researchers. TRIAL REGISTRATION: ACTRN, ACTRN382863 . Registered 19/10/2021 - Retrospectively registered. STUDY STATUS: recruiting.

Child and adolescent COVID-19 vaccination status and reasons for non-vaccination by parental vaccination status.

OBJECTIVES: COVID-19 vaccines are recommended for children ages ≥5 years. To develop effective interventions to increase uptake, this study explores reasons for parental hesitancy of child and adolescent COVID-19 vaccination. STUDY DESIGN: The Household Pulse Survey (HPS) is a nationally representative cross-sectional online household survey of adults aged ≥18 years that began data collection in April 2020 to help understand household experiences during the COVID-19 pandemic. METHODS: Using data from December 29, 2021, to January 10, 2022 (n = 11,478), we assessed child and adolescent COVID-19 vaccination coverage and parental intent to vaccinate their children and adolescents. Factors associated with child and adolescent vaccination coverage were examined using multivariable regression models. Reasons for not having had their child or adolescent vaccinated, stratified by parental vaccination status, were compared using tests of differences in proportions. RESULTS: Less than one-half (42.3%) of children and three-quarters (74.8%) of adolescents are vaccinated. Vaccination coverage was lower among households with lower education, as well as among children who had not had a preventive check-up in the past year. Parents of unvaccinated children were more likely to report that they do not trust COVID-19 vaccines, do not trust the government, and do not believe children need a COVID-19 vaccine compared to parents of vaccinated children. CONCLUSION: Efforts to increase uptake of vaccines by children and adolescents should target those with lower education, reassure parents of the vaccine safety and efficacy for themselves and their children/adolescents, and support yearly preventive care visits for their children.

[The association between aeroallergenic structures and allergic rhinitis: a study on northern Vietnam]. / Assotsiatsiya mezhdu strukturami aeroallergenov i allergicheskim rinitom: issledovanie o severe V'etnama.

Recently, there has been an increase in the number of patients with allergic rhinitis (AR) and the number of publications devoted to this problem is increasing. The main etiological factors of AR are pollen of trees, meadow and weeds, as well as mold spores, household allergens and epidermis of animals. Epidemiological studies have found that the prevalence and structure of AR are influenced by regional characteristics, such as the climatic and geographical and social characteristics of the region, and successively therapeutic and preventive algorithms in AR are also different. AIM: To examine the phenotype of the incidence of AR in connection with the characteristics of aeroallergens under the influence of climatic and geographical conditions in northern Vietnam, to make a new contribution to knowledge about AR in Asia and to increase the effect of treatment and prevention in this territory. MATERIALS AND RESEARCH METHODS: The study was conducted in the period from 06.2018 to 09.2018 on the basis of the ENT department of Thainguyen Central Hospital, Vietnam. A total of 556 patients with pathology of ENT organs aged 18 to 70 years were examined, 158 cases of chronic rhinitis were revealed. Among data from 158 patients, 64 patients were diagnosed with AR. We used otorhinolaryngological examination, a standard specific allergological examination and carried out aeropolyneological research in the city of the northern Vietnam, from 06.2018 to 06.2019. RESULT: The aerobiological spectrum is dominated by pollen from the families Moraceae, Urticaceae, Poaceae, Acacia, Artemisia, fern spores and fungal spores from the genus Alternaria. Among patients with chronic rhinitis, 40% were diagnosed with AR, 98.44% of them year-round or perennial AR, with predominant sensitization to house dust mites and molds, much more often to plant pollen. Among 9 (14.06%) patients diagnosed with a polyp of the nasal cavity, 6 (9.37%) patients had increased levels of specific IgE in the blood to a mixture of molds. Sensitization in patients with AR with hypertrophy of the mucous membrane of the nasal cavity is predominant on house dust. CONCLUSION: Predominantly, AR in northern Vietnam was year-round. Especially the connection between the formation of a polyp of the nasal cavity and hypersensitivity to fungal spores has been indicated, which may also indicate the role of social factors in further recommendations for the diagnosis, treatment and prevention of AR in patients living in North Vietnam.

Association between local indoor smoking ordinances in Massachusetts and cigarette smoking during pregnancy: a multilevel analysis.

OBJECTIVE: To estimate the association between local clean indoor air ordinances and prenatal maternal smoking across 351 municipalities in Massachusetts before the 2004 statewide ban and to test the effect of time since ordinance adoption on the association. METHODS: The authors linked 2002 birth certificate data of women who gave birth in the state and reported a Massachusetts residence (n=67,584) to a database of indoor smoking ordinances in all municipalities. Multilevel regression models accounting for individual- and municipality-level variables estimate the associations between the presence of local smoking ordinances, strength of the ordinances, time since ordinance adoption and prenatal smoking. RESULTS: Compared with those living in municipalities with no ordinances, women living in municipalities with a smoking ordinance had lower odds of prenatal smoking (OR=0.72, CI=0.53 to 0.98). No effect was found for 100% smoke-free ordinances. For the analyses testing the effect of time, pregnant women living in municipalities with ordinances enacted >2 years were less likely to smoke than those in municipalities with more recent (<1 year) ordinances. CONCLUSIONS: Preventing smoking among women of reproductive age is a public health priority. This study suggests that indoor smoking ordinances were associated with lower prenatal smoking prevalence and the favourable effect increased over time. Findings highlight the public health benefit of tobacco control policies.

Expression of epidermal growth factors and a tight junction protein in the nasal mucosa of patients with chronic hypertrophic rhinitis.

BACKGROUND: ErbB family receptors and tight junction proteins participate in the pathologic process including tissue remodelling of inflammatory diseases in the upper and lower respiratory tracts. This study aimed at investigating the expressions of erbB1, 2, 3, 4, and a tight junction protein, claudin-1, in the nasal mucosa of patients with chronic hypertrophic rhinitis. METHODS: Inferior turbinates were collected from 10 turbinectomised patients with allergic and non-allergic chronic hypertrophic rhinitis. The expressions of erbB1, 2, 3, 4, and claudin-1 were examined by fluorescence immunohistochemistry and by quantitative real-time transcription-polymerase chain reaction (qRT-PCR). RESULTS: All erbB1-4 and claudin-1 were detected, and mainly localised in the epithelial cells and nasal gland cells. The immunoreactivity for claudin-1 was positively correlated with the expressions of erbB1, 2 and 4, but negatively correlated with that of erbB3. The mRNA expressions of erbB1, 2 and 4 were positively correlated with one another, whereas the expression of erbB3 showed negative correlation with the immunoreactivity for erbB2 and 4. CONCLUSIONS: These results suggest a possible participation of erbBs and claudin-1 in tissue remodelling in chronic hypertrophic rhinitis.

Study protocol for The GOAL Trial: comprehensive geriatric assessment for frail older people with chronic kidney disease to increase attainment of patient-identified goals-a cluster randomised controlled trial.

BACKGROUND: An increasing number of older people are living with chronic kidney disease (CKD). Many have complex healthcare needs and are at risk of deteriorating health and functional status, which can adversely affect their quality of life. Comprehensive geriatric assessment (CGA) is an effective intervention to improve survival and independence of older people, but its clinical utility and cost-effectiveness in frail older people living with CKD is unknown. METHODS: The GOAL Trial is a pragmatic, multi-centre, open-label, superiority, cluster randomised controlled trial developed by consumers, clinicians, and researchers. It has a two-arm design, CGA compared with standard care, with 1:1 allocation of a total of 16 clusters. Within each cluster, study participants ≥ 65 years of age (or ≥ 55 years if Aboriginal or Torres Strait Islander (First Nations Australians)) with CKD stage 3-5/5D who are frail, measured by a Frailty Index (FI) of > 0.25, are recruited. Participants in intervention clusters receive a CGA by a geriatrician to identify medical, social, and functional needs, optimise medication prescribing, and arrange multidisciplinary referral if required. Those in standard care clusters receive usual care. The primary outcome is attainment of self-identified goals assessed by standardised Goal Attainment Scaling (GAS) at 3 months. Secondary outcomes include GAS at 6 and 12 months, quality of life (EQ-5D-5L), frailty (Frailty Index - Short Form), transfer to residential aged care facilities, cost-effectiveness, and safety (cause-specific hospitalisations, mortality). A process evaluation will be conducted in parallel with the trial including whether the intervention was delivered as intended, any issue or local barriers to intervention delivery, and perceptions of the intervention by participants. The trial has 90% power to detect a clinically meaningful mean difference in GAS of 10 units. DISCUSSION: This trial addresses patient-prioritised outcomes. It will be conducted, disseminated and implemented by clinicians and researchers in partnership with consumers. If CGA is found to have clinical and cost-effectiveness for frail older people with CKD, the intervention framework could be embedded into routine clinical practice. The implementation of the trial's findings will be supported by presentations at conferences and forums with clinicians and consumers at specifically convened workshops, to enable rapid adoption into practice and policy for both nephrology and geriatric disciplines. It has potential to materially advance patient-centred care and improve clinical and patient-reported outcomes (including quality of life) for frail older people living with CKD. TRIAL REGISTRATION: ClinicalTrials.gov NCT04538157. Registered on 3 September 2020.

The Effect of Price Changes and Teaspoon Labelling on Intention to Purchase Sugar-Sweetened Beverages: A Discrete Choice Experiment.

INTRODUCTION: Childhood obesity is a major public health concern and sugar-sweetened beverages (SSBs) are a known contributor. SSB taxation and food labelling have been proposed as policies to reduce consumption by changing purchasing behaviours. The study aimed to analyse caregivers' preferences on commonly purchased SSBs in Australia and to determine the effect of price increases and teaspoon labelling on their purchasing intentions. METHODS: We used a discrete choice experiment (DCE) to obtain data about choices between SSB and non-SSB alternatives. 563 caregivers, who had young children aged 3-7 years, completed the experiment online. 286 were randomly allocated to receive choice sets with plain labelling while 277 were assigned to teaspoon labelling. Each participant completed nine choice scenarios where they chose between six SSB and non-SSB beverage options or a no-beverage option, with beverage prices varying between scenarios. While hypothetical, price and teaspoon labelling for sugar content for each beverage was obtained from an informal market survey. Responses from the DCE were modelled using random parameters logit within a random utility theory framework. Household income and children's consumption volumes of soft drink were used to explore preference heterogeneity. RESULTS: Using mixed logit as the final model, we found that higher reduction in intended purchases was observed for soft drink and fruit drink in teaspoon labelling than it was in plain labelling. Participants exposed to teaspoon labelling intended to purchase less of flavoured milk and fruit juice compared to those exposed to plain labelling. Compared to baseline prices, a hypothetical 20% increase in SSB prices and the presentation of 'teaspoons of sugar' labelling were predicted to reduce intentional SSB purchases and increase intentional non-SSB purchases. Within each labelling group, there were no significant differences of intentional purchases between the highest and the lowest income quintile, high and low consumers of soft drinks. However, compared to plain labelling, teaspoon labelling was predicted to strongly influence intentional purchases of SSBs and non-SSBs. CONCLUSION: This study suggests that a policy to increase SSB price and include teaspoon labelling would lead to a reduced consumption of SSBs and increased consumption of non-SSBs.

Effects of temperature and viscosity on miracidial and cercarial movement of Schistosoma mansoni: ramifications for disease transmission.

Parasites with complex life cycles can be susceptible to temperature shifts associated with seasonal changes, especially as free-living larvae that depend on a fixed energy reserve to survive outside the host. The life cycle of Schistosoma, a trematode genus containing some species that cause human schistosomiasis, has free-living, aquatic miracidial and cercarial larval stages that swim using cilia or a forked tail, respectively. The small size of these swimmers (150-350 µm) dictates that their propulsion is dominated by viscous forces. Given that viscosity inhibits the swimming ability of small organisms and is inversely correlated with temperature, changes in temperature should affect the ability of free-living larval stages to swim and locate a host. By recording miracidial and cercarial movement of Schistosoma mansoni using a high-speed camera and manipulating temperature and viscosity independently, we assessed the role each factor plays in the swimming mechanics of the parasite. We found a positive effect of temperature and a negative effect of viscosity on miracidial and cercarial speed. Reynolds numbers, which describe the ratio of inertial to viscous forces exerted on an aquatic organism, were <1 across treatments. Q10 values were <2 when comparing viscosity treatments at 20 °C and 30 °C, further supporting the influence of viscosity on miracidial and cercarial speed. Given that both larval stages have limited energy reserves and infection takes considerable energy, successful transmission depends on both speed and lifespan. We coupled our speed data with mortality measurements across temperatures and discovered that the theoretical maximum distance travelled increased with temperature and decreased with viscosity for both larval stages. Thus, our results suggest that S. mansoni transmission is high during warm times of the year, partly due to improved swimming performance of the free-living larval stages, and that increases in temperature variation associated with climate change might further increase transmission.

Determination of wild animal sources of fecal indicator bacteria by microbial source tracking (MST) influences regulatory decisions.

Fecal indicator bacteria (FIB) are used to assess fecal pollution levels in surface water and are among the criteria used by regulatory agencies to determine water body impairment status. While FIB provide no information about pollution source, microbial source tracking (MST) does, which contributes to more direct and cost effective remediation efforts. We studied a watershed in Florida managed for wildlife conservation that historically exceeded the state regulatory guideline for fecal coliforms. We measured fecal coliforms, enterococci, a marker gene for avian feces (GFD), and a marker gene for human-associated Bacteroides (HF183) in sediment, vegetation, and water samples collected monthly from six sites over two years to: 1) assess the influence of site, temporal factors, and habitat (sediment, vegetation, and water) on FIB and MST marker concentrations, 2) test for correlations among FIB and MST markers, and 3) determine if avian feces and/or human sewage contributed to FIB levels. Sediment and vegetation had significantly higher concentrations of FIB and GFD compared to water and thus may serve as microbial reservoirs, providing unreliable indications of recent contamination. HF183 concentrations were greatest in water samples but were generally near the assay limit of detection. HF183-positive results were attributed to white-tailed deer (Odocoileus virginianus) feces, which provided a false indication of human sewage in this water body. FIB and GFD were positively correlated while FIB and HF183 were negatively correlated. We demonstrated that birds, not sewage, were the main source of FIB, thus avoiding implementation of a total maximum daily load program (TMDL). Our results demonstrate that the concomitant use of FIB and MST can improve decision-making and provide direction when water bodies are impaired, and provides a strategy for natural source exclusion in water bodies impacted by wild animal feces.

Expression of a mutant prohibitin from the aP2 gene promoter leads to obesity-linked tumor development in insulin resistance-dependent manner.

A critical unmet need for the study of obesity-linked cancer is the lack of preclinical models that spontaneously develop obesity and cancer sequentially. Prohibitin (PHB) is a pleiotropic protein that has a role in adipose and immune functions. We capitalized on this attribute of PHB to develop a mouse model for obesity-linked tumor. We achieved this by expressing Y114F-PHB (m-PHB) from the aP2 gene promoter for simultaneous manipulation of adipogenic and immune signaling functions. The m-PHB mice develop obesity in a sex-neutral manner, but only male mice develop impaired glucose homeostasis and hyperinsulinemia similar to transgenic mice expressing PHB. Interestingly, only male m-PHB mice develop histiocytosis with lymphadenopathy, suggesting that metabolic dysregulation or m-PHB alone is not sufficient for the tumor development and that both are required for tumorigenesis. Moreover, ovariectomy in female m-PHB mice resulted in impaired glucose homeostasis, hyperinsulinemia and consequently tumor development similar to male m-PHB mice. These changes were not observed in sham-operated control m-Mito-Ob mice, further confirming the role of obesity-related metabolic dysregulation in tumor development in m-PHB mice. Our data provide a proof-of-concept that obesity-associated hyperinsulinemia promotes tumor development by facilitating dormant mutant to manifest and reveals a sex-dimorphic role of PHB in adipose-immune interaction or immunometabolism. Targeting PHB may provide a unique opportunity for the modulation of immunometabolism in obesity, cancer and in immune diseases.

Is vitrification involved in depression of the phase transition temperature in dry phospholipids?

Recent literature has suggested that the depression of the phase transition temperature (Tm) in dry phospholipids by sugars may be ascribed to vitrification of the stabilizing solute, rather than by the direct interaction between sugar and phospholipid we have proposed. Koster et al. ((1994) Biochim. Biophys. Acta 1193, 143-150) claim that the only necessity is that the glass transition (Tg) for the sugar exceed Tm for the lipid. Evidence is presented in the present paper that this is not sufficient. Based on the vitrification hypothesis of Koster et al., the predicted order of effectiveness in depressing Tm in dry dipalmitoylphosphatidylcholine (DPPC) is dextran > or = hydroxyethyl starch > stachyose > raffinose > trehalose > sucrose > glucose. In fact, the opposite order was seen. The effect of raffinose, sucrose, or trehalose on Tm in dry DPPC depends on the thermal history of the sample, as we have reported previously. When DPPC dried with trehalose is heated for the first time, Tm is about 55 degrees C, but on the second and subsequent heating scans Tm falls to about 25 degrees C. Koster et al. suggest that this effect is due to heating the sample above Tg rather than to melting the hydrocarbon chains. We present evidence here that all that is required is for the chains to be melted. Further, we show that retention of residual water by DPPC dried with trehalose depends on the drying temperature, but is independent of drying temperature with glucose, a finding that is consistent with direct interaction. We conclude that vitrification is not in itself sufficient to depress Tm in dry phospholipids.

The outcome of cardiac operations in infants weighing two kilograms or less.

OBJECTIVE: A review of our recent experience of operating on infants weighing 2 kg or less who had congenital heart disease was performed to determine the outcome of early surgical repair or palliation. METHODS: A retrospective review of hospital records was performed for infants who weighed 2 kg or less and who were identified to have undergone cardiac operation at our institution January 1992 to June 1997. The data collected included age, weight, gestational age, cardiac diagnosis, surgical procedure, and outcome measures such as length of stay, morbidity, and mortality rate. Outpatient charts were reviewed for follow-up survival and cardiac status. RESULTS: Thirty-three operations were performed on 30 patients. Median age at operation was 19.5 days (1 to 140 days), and median weight was 1.8 kg (1.1 to 2.0 kg). Cardiac diagnoses varied, with coarctation of the aorta and tetralogy of Fallot most common. Twenty-four patients were born at 37 or fewer weeks' gestation. Hospital survival was 83% with no difference in mortality rates based on age, weight, or type of surgical procedure. Premature infants tended to have worse hospital survival. Median postoperative length of stay was 39 days (6 to 122 days). Median duration of mechanical ventilation in survivors was 6 days (2 to 24 days). Neurologic complications were documented in eight patients. Of the 25 hospital survivors, 20 (80%) are alive with good cardiac status at a mean follow-up of 13 months. CONCLUSION: Cardiac operations in a selected group of infants weighing 2 kg or less can provide acceptable hospital survival. In most instances, complete repair is possible with good medium-term outcome in the survivors. Investigation into neurologic outcomes in these patients is warranted.

Congenital Heart Surgery Nomenclature and Database Project: aortic valve disease.

The extant nomenclature for aortic valve disease is reviewed for the purpose of establishing a unified reporting system. The subject was debated and reviewed by members of the STS-Congenital Heart Surgery Database Committee and representatives from the European Association for Cardiothoracic Surgery. All efforts were made to include all relevant nomenclature categories using synonyms where appropriate. Aortic valve disease has been subdivided into stenotic and regurgitant lesions. Stenotic lesions have been characterized by anatomic location: supravalvar, valvar, and subvalvar. Regurgitant lesions have been characterized as either congenital or acquired. A comprehensive database set is presented that is based on a hierarchical scheme. Data are entered at various levels of complexity and detail that can be determined by the clinician. These data can lay the foundation for comprehensive risk stratification analyses. A minimum database set is also presented that will allow for data sharing and would lend itself to basic interpretation of trends. Outcome tables relating diagnoses, procedures, and various risk factors are presented.

Natural history of descending thoracic and thoracoabdominal aneurysms.

BACKGROUND: A review of 165 patients with chronic dissecting and degenerative aneurysms of the descending thoracic and thoracoabdominal aorta initially managed nonoperatively was carried out to ascertain factors associated with a high risk of rupture. METHODS: Changes in the aneurysms were followed with three-dimensional reconstructions of computed tomograph scans. Risk factors were compared in patients with dissecting and nondissecting aneurysms who experienced rupture, in whom operation was recommended during the course of follow-up, and in those without rupture or operation. RESULTS: Nondimensional variables associated with an enhanced risk of rupture include age, the presence of chronic obstructive pulmonary disease, and even uncharacteristic continued pain. Patients with rupture of dissections had significantly higher blood pressures than survivors, and significantly smaller maximal descending thoracic aortic diameters (median 5.4 cm) than patients with rupture of degenerative aneurysms (median 5.8 cm). The extent of the aneurysm, as reflected by the maximal abdominal aortic diameter, was a significant risk factor for rupture only in nondissecting aneurysms. Mortality from rupture was significantly higher in patients with chronic dissections than in patients with nondissecting aneurysms: 9/10 vs 26/34 (p = 0.004). CONCLUSIONS: Almost 20% of patients followed nonoperatively succumbed to rupture, suggesting that a more aggressive surgical approach toward patients with chronic aneurysms of the descending thoracic and thoracoabdominal aorta is warranted. An individualized risk of rupture within 1 year can now be calculated, and patients whose operative risk is lower than their calculated risk should be offered elective surgery.

Use of somatosensory evoked potentials for thoracic and thoracoabdominal aortic resections.

BACKGROUND: Despite tremendous development in surgical and anesthetic techniques, resection of the thoracic and thoracoabdominal segments of the aorta remain associated with the risk of paralysis. Routine use of somatosensory-evoked potential (SEP) monitoring in patients undergoing surgery of the thoracic aorta has become a standard intra- and postoperative procedure at our institution since its first use in 1993. METHODS: One hundred forty nine (149) thoracic aortic operations were performed during January 1993 through January 1998 using SEP-directed serial sacrifice of paired intercostal arteries. Full, partial, or no cardiovascular bypass was variably used, dictated by anatomy; 49 patients required deep hypothermic circulatory arrest (DHCA). Patients were monitored during both the intraoperative procedure as well for the post-anesthesia period until neurologic stability and/or ability to reproducibly demonstrate lower extremity neurologic competency was established. Postoperative neurologic function was compared to ischemic intervals, extent of aortic resection, number of intercostal arteries sacrificed, type of perfusion, and underlying aortic pathology. RESULTS: Overall mortality in the group was 13 patients (8.7%), with no one cause predominating. Nine patients sustained permanent paraplegia, only 1 of whom lost SEPs during the procedure. Abnormal SEPs were seen in 19 patients, 14 of whom had normal neurologic function after awakening. Three of 19 (15.8%) developed late paraplegia that resolved with medical therapy. Eleven patients (7.4%) developed cerebrovascular accidents (CVA), with the majority (8) appearing in the group undergoing DHCA. The risk of CVA was significantly higher in DHCA patients (p < 0.01) than other patients. No patient with CVA had abnormal SEPs; 4 DHCA patients developed abnormal SEPs, 1 with permanent paralysis. CONCLUSIONS: The routine use of SEP monitoring during thoracic and thoracoabdominal aortic surgery as well as during the postoperative period may be useful in decreasing the observed incidence of paraplegic events associated with these procedures.

Subtypes of acute aortic dissection.

BACKGROUND: This series consists of a 12-year experience with a policy of identifying and replacing the aortic segment containing the primary intimal tear for repair of acute aortic dissection. METHODS: Patients with type A dissection underwent urgent surgery. Patients with type B dissection were referred for surgery based on selective criteria, including aortic dilatation greater than 5 cm. A classification system for acute dissection is described that specifies the site of intimal tear while retaining the clinical relevance of the Stanford system. RESULTS: Of 168 acute dissections, 139 were type A and 29 were type B. The site of intimal tear was as follows: ascending aorta, 83 cases; arch, 32 cases; descending aorta, 29 cases; multiple tears, 11 cases (10 included arch tears); no tear (intramural hematoma), 6 cases; not noted, 7 cases. Only 60% of acute type A dissections arose from solitary intimal tears in the ascending aorta, whereas 30% had arch tears. Hospital mortality for type A dissection was 13.7% (18.8% for arch tears, NS) and 0% for type B. False lumen patency was 57.1% for type A dissection and 18.8% for type B dissection (p = 0.002), yet survival was similar for these groups. Ten-year survival for type A dissection with arch tear (0.51 +/- 0.12) was lower than 10-year survival for type A dissection with ascending tear (0.74 +/- 0.05; p = 0.77), and significantly lower than for type A dissection with descending tear (0.88 +/- 0.12; p = 0.029). CONCLUSIONS: Systematic resection of the primary tear yielded similar hospital mortality, 5-year survival, and aorta-related event-free survival rates for subtypes of acute type A dissection. Excellent results were obtained with a selective approach to type B dissection.

Prospective study of the natural history of thoracic aortic aneurysms.

BACKGROUND: The decision whether or not to recommend resection of moderately large descending thoracic and thoracoabdominal aneurysms requires weighing the relatively high mortality and significant risk of paraplegia associated with operation against the likelihood that the aneurysm will rupture spontaneously, with an almost invariably fatal outcome. To better define the risk of aneurysm rupture, we undertook a prospective study of patients who had not had operation on their moderately large descending thoracic and thoracoabdominal aneurysms. METHODS: Patients were enrolled at the time of their second computed tomographic scans: three-dimensional computer-generated reconstructions allowed determination of several dimensional parameters for each study, including diameters and cross-sectional areas at the site of maximal dilatation in the descending aorta and in the abdomen as well as total thoracoabdominal surface area. Comparisons of serial studies permitted calculation of yearly rates of change in these dimensions. RESULTS: Of 114 patients, 8 died of causes unrelated to the aneurysm, 26 died of rupture, 20 met previously determined criteria for operation, and 60 survived without operation or rupture. Multivariate regression analysis identified maximal diameter in the descending and in the abdominal aorta as independent risk factors for rupture, as well as older age, the presence of even uncharacteristic pain, and a history of chronic obstructive pulmonary disease. A piecewise exponential model enabled construction of an equation allowing calculation of rate of rupture in patients in whom the values of the risk factors are known, and also of the probability of rupture in a given individual over a specified time interval. CONCLUSIONS: Because using this equation--based on easily determined risk factors (age, pain, chronic obstructive pulmonary disease, maximal thoracic and maximal abdominal aortic diameter)--allows the risk of aneurysm rupture within a given interval to be estimated fairly accurately for each individual patient, it is our current practice to recommend operation when the calculated risk of rupture within 1 year exceeds the anticipated mortality of elective operation, rather than relying on general operative guidelines based almost exclusively on aneurysm size.

Changes in the expression of extracellular matrix (ECM) and matrix metalloproteinases (MMP) of proliferating rat parotid acinar cells.

Tissue morphogenesis, development, and maintenance of function are mediated by signals generated through the composition of the extracellular matrix. The regulation of the composition of matrix is determined by enzymes specific for their degradation, the matrix metalloproteinases. Chronic injections of the beta-adrenergic receptor agonist, isoproterenol, result in a non-neoplastic hypertrophy and hyperplasia of the rat parotid gland. The activity of matrix metalloproteinases, as measured by gelatin zymography and enzymatic digestion of Azocoll substrates by gland lysates, decreased significantly (P < 0.05) following 24 hrs of agonist treatment, and slowly recovered to control values by 6 days of treatment. Daily administration of the broad-spectrum matrix metalloproteinase inhibitor Galardin for 3 days in combination with isoproterenol resulted in enhanced gland hypertrophy compared with that produced by isoproterenol alone. Given alone, Galardin also caused hypertrophy. The relative abundance of mRNA for the extracellular matrix molecules, collagens I and III and fibronectin, declined rapidly following the initiation of beta-agonist treatment in vivo, while laminin B1 and B2 mRNA levels increased initially before declining below control levels. These changes in patterns of mRNA levels also were observed in the concentrations of glandular protein when Western dot blot analysis of collagens I and III and laminin, respectively, was used. The importance of laminin, in vivo, was demonstrated by coinjection of anti-laminin antibody along with isoproterenol, which resulted in the inhibition of beta-agonist-induced parotid gland hypertrophy and hyperplasia. These data suggest that modulation of the ECM is associated with isoproterenol-induced salivary gland hypertrophy and hyperplasia. It is likely that this modulation of the ECM takes place through transcriptional regulation of some ECM genes and regulation of matrix-degrading enzyme activity.

Assessment of bromhexine as a treatment regimen in Sjögren's syndrome-like disease in the NOD (non-obese diabetic) mouse.

OBJECTIVE: Bromhexine has been reported to alleviate the xerostomia and xerophthalmia associated with secondary Sjögren's syndrome. The aim of this study was to determine if it might prove useful in the treatment of Sjögren's syndrome-like disease of the NOD mouse model for autoimmune sialoadenitis. METHODS: Groups of mice were divided into sets receiving 60 mg/kg bromhexine in drinking water and control pair-fed animals. The efficacy of drug treatment was assessed by weekly measurement of stimulated saliva volumes, protein concentration, and amylase activity. At termination (20 weeks) submandibular and lacrimal glands were removed to assess the levels of lymphocytic infiltration by histological evaluation under light microscopy. RESULTS: Control and bromhexine-treated groups of mice showed no difference in the loss or rate of reduction in stimulated saliva flow over the 12 weeks of treatment. No differences were noted in the protein concentration and amylase loss with increasing age of the animals. Similar temporal changes in total protein profiles and aberrant expression of the 20 kDa parotid secretory protein isoform were observed by SDS-polyacrylamide gel profiles and Western bolt analysis. Histological evaluation of exocrine gland sections failed to detect any reduction in focal lymphocyte infiltration. CONCLUSION: Bromhexine therapy did not alter the development or severity of Sjögren's syndrome-like disease in the NOD mouse model for autoimmune sialoadenitis.