First quantitative dosages: Strong correlations between non-5-HT2Rs serotonin receptors on normal human heart valves

Objectives

Although critical in animal and human development and pathology, a measurement of the quantitative expression of 5-HTR serotonin receptors on animal or human valvular tissues has never been performed.

Methods

Quantification of the most frequent 5-HTRs reported as being present in human peripheral tissue was performed using radiolabeled agonists/antagonists. A membrane protein extract from normal human valves (aortic/mitral/tricuspid and some pulmonary) and associated diseased left myocardium, all unusable in clinics, were obtained from the Homograft bank.

Results

We analyzed 5-HT1AR/5-HT1B/DR/5-HT2AR/5-HT2BR/5-HT 2CR/5-HT4R/5-HT7R from 28 hearts. We confirmed the presence of tissue and measured the quantitative content for respective proteins in femtomol/mg of protein extracts: for 5-HT2AR (35.9+/−0.7), 5-HT2BR (28.8+/−1.3) but also a newly observed and robust expression for 5-HT4R (38+/−4.2). We identified one, 5-HT1ARs (4.9+/−0.3), and the possible expression, but at a very low level, of previously reported 5-HT1B/DRs (1.3+/−0.5) as well as the new 5-HT7Rs (3.5+/0.1) and 5-HT2CRs (1.2+/−0.1). Interestingly, by using univariate analysis, we were able to observe many correlations between the different 5-HTR levels of expression especially between 5-HT1AR/5-HT1B/DR and also between 5-HT4R/5-HT7R, but none were observed between 5-HT2AR and 5-HT2BR. Using multivariate analyses for a specific 5-HTR level of expression, after adjustment for implantation sites and other 5-HTRs, we found that 5-HT1AR was correlated with 5-HT1B/DR;5-HT4R with 5-HT7R and 5-HT1AR;5-HT2BR with 5-HT2AR only. For 5-HT2C, no correlation was observed.

Conclusion

5-HT2AR/5-HT2BR and 5-HT4R were all observed to have a high and equal level of expression on human valves, but that of 5-HT1AR was more limited. Since these non-5-HT2Rs are coupled with different G-proteins, with specific signaling, theoretically they may control the main 5-HT2R signaling (i.e., PLC/DAG-PKC-ERK/Ras/Src signaling) involved in valvular fibrosis and degeneration.

End-Stage Respiratory Failure Secondary to Bronchiolitis Obliterans Syndrome Induced by Toxic Epidermal Necrosis, Also Known as Lyell Syndrome: A Case Report

BACKGROUND

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are rare but serious dermatologic diseases. They can be associated with systemic manifestations such as bronchiolitis obliterans syndrome (BOS). SJS/TEN-induced BOS is associated with a poor prognosis, and no guidelines exist regarding its management. Several case reports have described the association between SJS/TEN and BOS, with few patients undergoing lung transplantation as a last resort therapy. Unfortunately, in the published reports, none of the transplanted patients were observed for a long period of time after the transplantation; therefore, the long-term mortality as well as the risk of recurrence of BOS could not be inferred from these reports.

CASE REPORT

We present the case of a young patient diagnosed with SJS complicated by BOS and end-stage respiratory failure refractory to corticosteroid therapy. She underwent bilateral lung transplantation with an outstanding outcome at 5-year follow-up.

CONCLUSION

SJS/TEN-induced BOS might have a favorable evolution and long-term outcomes following lung transplantation. However, prospective studies are needed to confirm this finding.

Blood CD9+ B cell, a biomarker of bronchiolitis obliterans syndrome after lung transplantation

Bronchiolitis obliterans syndrome is the main limitation for long-term survival after lung transplantation. Some specific B cell populations are associated with long-term graft acceptance. We aimed to monitor the B cell profile during early development of bronchiolitis obliterans syndrome after lung transplantation. The B cell longitudinal profile was analyzed in peripheral blood mononuclear cells from patients with bronchiolitis obliterans syndrome and patients who remained stable over 3 years of follow-up. CD24^hi CD38^hi transitional B cells were increased in stable patients only, and reached a peak 24 months after transplantation, whereas they remained unchanged in patients who developed a bronchiolitis obliterans syndrome. These CD24^hi CD38^hi transitional B cells specifically secrete IL-10 and express CD9. Thus, patients with a total CD9⁺ B cell frequency below 6.6% displayed significantly higher incidence of bronchiolitis obliterans syndrome (AUC = 0.836, PPV = 0.75, NPV = 1). These data are the first to associate IL-10-secreting CD24^hi CD38^hi transitional B cells expressing CD9 with better allograft outcome in lung transplant recipients. CD9-expressing B cells appear as a contributor to a favorable environment essential for the maintenance of long-term stable graft function and as a new predictive biomarker of bronchiolitis obliterans syndrome-free survival.

Catamenial and Noncatamenial, Endometriosis-related or Nonendometriosis-related Pneumothorax Referred for Surgery

RATIONALE

Catamenial and endometriosis-related pneumothorax are considered relatively rare entities. Their clinical characteristics and outcome are incompletely known.

OBJECTIVES

To evaluate the frequencies, clinical characteristics, and outcomes of catamenial and endometriosis-related pneumothoraces occurring in women with no underlying lung disease referred for surgical treatment.

METHODS

Clinical files of all the women of reproductive age referred to our center during a 6-year period for surgical treatment of spontaneous pneumothorax were retrospectively reviewed. Catamenial pneumothorax (CP) was defined as recurrent pneumothorax occurring between the day before and within 72 hours after the onset of menses. All histologic slides were reviewed to confirm initial diagnoses.

MEASUREMENTS AND MAIN RESULTS

A total of 114 women underwent video-assisted thoracic surgery; 28 women (24.6%) had CP (right-sided in all but one), and diaphragmatic abnormalities (perforations and/or nodules) were observed in 22 of them. Diaphragmatic abnormalities were seen in 21 of 86 patients with non-CP. Histologic examination found endometriosis, mainly diaphragmatic, in 18 of 28 CPs and 11 of 86 non-CPs. A 6-month antigonadotropic treatment was prescribed postoperatively to women with either CP or endometriosis-related pneumothorax. Mean follow-up was 32.7 (+/-18.5) months. Recurrence rates in CP, non-CP but endometriosis-related, and non-CP non-endometriosis-related pneumothoraces were 32, 27, and 5.3%, respectively.

CONCLUSIONS

Our experience shows that (1) CP and/or endometriosis-related pneumothoraces account for an important percentage of spontaneous pneumothoraces referred for surgery, (2) diaphragmatic abnormalities seem to play a fundamental role in their pathogenesis, and (3) management is difficult because of the high recurrence rate.

A surgical predictive risk model of in-hospital mortality for primary resectable lung cancer: Statistical analysis of 8,796 patients from a nationally representative database

7677

Background: The aim of this study was twofold: to identify factors associated with in-hospital mortality among patients operated on for primary resectable lung cancer and to construct a risk model that could be used prospectively to inform decisions and retrospectively to enable comparisons and outcomes. Methods: Data from a nationally representative thoracic surgery database were collected prospectively in 59 hospitals between June 1, 2002 and December 1, 2006. Only adult patients with more than 95% of completed data were selected for the final analysis (n = 8,796 patients). Logistic regression analysis was used to predict the risk of in-hospital mortality. A risk model was developed with a training set of data (50% of patients) and validated on an independent test set (50% of patients). Its fit was assessed by the Hosmer-Lemeshow test (larger p value signifies greater reliability), and predictive accuracy was indicated by the area under the receiver operating characteristic curve (c-index). Results: Of the 8,796 original patients, 255 (2.9%) died during the same hospital admission. Within the data used to develop the model, the factors found to be significantly associated with the occurrence of in-hospital mortality in a multivariate analysis were: age, gender, performance status (World Health Organization) classification, side, class of procedure (lobectomy or wedge resection versus pneumonectomy), tumor histology, TNM stages and presence of co-morbid disease. The model was reliable (Hosmer-Lemeshow test = 8.94; p = 0.35) and accurate: the c-index (95% confidence interval) = 0.83 (0.81 to 0.85) for the training set and 0.82 (0.79 to 0.85) for the test set of data. The correlation between the expected and observed number of deaths was 0.99. Conclusions: The validated multivariate model for risk of in-hospital mortality among adult patients requiring surgery for primary resectable lung cancer described in this report was developed with national data, uses only 8 variables and has good performance characteristics. It would be useful both for calculating the mortality risk of an individual patient and contrasting expected and observed mortality rates for an institution or independent clinician.

No significant financial relationships to disclose.

Crystalloid versus cold blood cardioplegia and cardiac troponin I release

BACKGROUND

Cardiac troponin I (CTnI) has been shown to be a marker of myocardial injury. The aim of this study was to compare antegrade crystalloid cardioplegia with antegrade cold blood cardioplegia with warm reperfusion using CTnI release as the criteria for evaluating the adequacy of myocardial protection.

METHODS AND RESULTS

Seventy patients were randomly assigned to receive crystalloid or blood cardioplegia. CTnI concentrations were measured in serial venous blood samples drawn just before cardiopulmonary bypass and after aortic unclamping at 6, 9, 12, and 24 hours and daily thereafter for 5 days. ANOVA with repeated measures was performed to test the effect of the type of cardioplegia on CTnI release. The total amount of CTnI released was higher in the crystalloid cardioplegia group than in the blood cardioplegia group (11.2 +/- 8.9 versus 7.8 +/- 8.6 micrograms, P < .02). CTnI concentration was significantly higher in the crystalloid group than in the blood group in the samples drawn at hours 9 and 12. Three patients in each group had ECG evidence of perioperative myocardial infarction. Eight patients in the crystalloid group and five patients in the blood group had CTnI evidence of perioperative myocardial infarction. CTnI release was significantly lower in patients requiring no electrical defibrillation after aortic unclamping.

CONCLUSIONS

Cold blood cardioplegia followed by warm reperfusion is beneficial in an unselected group of patients with a preserved left ventricular function undergoing an elective first coronary artery bypass grafting. CTnI allowed the diagnosis of small perioperative necrotic myocardial areas. The need for electrical defibrillation after aortic unclamping was related to a higher release of CTnI. A further study is necessary to determine whether this technique was beneficial because of cold blood cardioplegia, warm reperfusion, or both.