Aluminum‐Catalyzed One‐Pot Synthesis of Polyester‐b‐Polypeptide Block Copolymers by Ring‐Opening Polymerization

Polypeptides are a class of important biomaterials that are extensively utilized in applications such as drug delivery systems, sensors, tissue engineering, biomimetic synthesis of ordered inorganic nanostructures, and catalysis. In particular, the association of polypeptides to polyesters in copolymer architectures provides versatile original materials. However, the catalytic formation of this type of peptide‐based copolymers remains a considerable synthetic challenge. Here, a new strategy to obtain copolymer materials by one‐pot catalysis is reported, which confers great interest to the approach.     

The Advantage of Imputation of Missing Income Data to Evaluate the Association Between Income and Self-Reported Health Status (SRH) in a Mexican American Cohort Study

Missing data often occur in cross-sectional surveys and longitudinal and experimental studies. The purpose of this study was to compare the prediction of self-rated health (SRH), a robust predictor of morbidity and mortality among diverse populations, before and after imputation of the missing variable “yearly household income.” We reviewed data from 4,162 participants of Mexican origin recruited from July 1, 2002, through December 31, 2005, and who were enrolled in a population-based cohort study. Missing yearly income data were imputed using three different single imputation methods and one multiple imputation under a Bayesian approach. Of 4,162 participants, 3,121 were randomly assigned to a training set (to derive the yearly income imputation methods and develop the health-outcome prediction models) and 1,041 to a testing set (to compare the areas under the curve (AUC) of the receiver-operating characteristic of the resulting health-outcome prediction models). The discriminatory powers of the SRH prediction models were good (range, 69–72%) and compared to the prediction model obtained after no imputation of missing yearly income, all other imputation methods improved the prediction of SRH (P < 0.05 for all comparisons) with the AUC for the model after multiple imputation being the highest (AUC = 0.731). Furthermore, given that yearly income was imputed using multiple imputation, the odds of SRH as good or better increased by 11% for each $5,000 increment in yearly income. This study showed that although imputation of missing data for a key predictor variable can improve a risk health-outcome prediction model, further work is needed to illuminate the risk factors associated with SRH.     

Trends in prevalence of prognostic factors and survival in lung cancer patients from 1985 to 2004 at a tertiary care center

Background: After a prolonged period of increasing rates of lung cancer incidence and mortality for both men and women, incidence and mortality rates are decreasing in men and stabilizing in women. The goal of this study was to assess changes over 20 years in the prevalence of known risk factors for lung cancer and to elucidate possible predictors associated with lung cancer survival. Methods: The study included a total of 908 patients with primary lung cancer referred to The University of Texas M.D. Anderson Cancer Center over three study periods 1985–1989 (N = 392), 1993–1997 (N = 216), and 2000–2004 (N = 300). Detailed questionnaires were used to collect information from the patients. Hazard ratios were estimated by fitting a Cox proportional hazards model. Using the Kaplan–Meier method, survival in months was calculated up to 2 years from the date of diagnosis to achieve comparability in the three groups. Results: We observed a decrease in the proportion of patients who are current cigarette smokers and an increase in the proportion of patients who present with adenocarcinoma of the lung, are obese and patients who present with localized disease. We also found an increase in the number of patients who report a family history of lung cancer. The overall median survival duration has increased over the years from 12.0 months in 1985–1989 to 17.5 months in 2000–2004. Also, the probability of survival of patients who were alive at 2 years after diagnosis has also increased (26.5% in 1985–1989 to 40.8% in 2000–2004). Overall, women had a better median survival than men. Conclusions: The results show that the demographic, histologic, clinical, and outcome variables of patients with lung cancer have changed over the past 20 years. Most important, the survival of patients with lung cancer has improved.     

Isolated sulphite oxidase deficiency mimics the features of hypoxic ischaemic encephalopathy

Isolated sulphite oxidase deficiency (ISOD) is a rare autosomal recessive inborn error of metabolism, which may present at birth with intractable seizures (often of prenatal onset) and severe neurological abnormalities. In infants who survive, lens dislocation may occur from 8 weeks of age. The neuropathological findings in ISOD are similar to those seen in severe perinatal asphyxia. We describe two siblings with ISOD born to healthy non-consanguineous parents. The first child presented within 48 h of birth with poor feeding and seizures. He died from septicaemia on day 20 of life. The clinical presentation, neuroradiology and autopsy suggested a diagnosis of severe hypoxic ischaemic encephalopathy with a low recurrence risk. The second child presented with seizures within an hour of birth. She lived for 16 months during which time she failed to make developmental progress and continued to experience intractable seizures. Her neuroradiology was similar to her brothers. A diagnosis of ISOD was suggested from high urinary S-sulphocysteine in the second child and confirmed by the absence of sulphite oxidase activity in skin fibroblast culture. The diagnosis has enabled the couple to access prenatal testing in a subsequent pregnancy. Conclusion:Isolated sulphite oxidase deficiency is an autosomal recessive condition which may mimic ischaemic encephalophathy. The disorder should be considered in all cases of intrauterine seizures, intractable seizures in the newborn period and infants with clinical and radiological features of ischaemic encephalophathy, especially when no obvious insult can be determined.E. Hobson and S. Thomas contributed equally to this paper