A residuals-based transition model for longitudinal analysis with estimation in the presence of missing data

We propose a transition model for analysing data from complex longitudinal studies. Because missing values are practically unavoidable in large longitudinal studies, we also present a two-stage imputation method for handling general patterns of missing values on both the outcome and the covariates by combining multiple imputation with stochastic regression imputation. Our model is a time-varying auto-regression on the past innovations (residuals), and it can be used in cases where general dynamics must be taken into account, and where the model selection is important. The entire estimation process was carried out using available procedures in statistical packages such as SAS and S-PLUS. To illustrate the viability of the proposed model and the two-stage imputation method, we analyse data collected in an epidemiological study that focused on various factors relating to childhood growth. Finally, we present a simulation study to investigate the behaviour of our two-stage imputation procedure.     

Evaluation of sleep disorders in cancer patients based on Pittsburgh Sleep Quality Index

Insomnia, poor sleep quality and short sleep durations are the most common problems seen in cancer patients. More studies are needed about sleep disorders in cancer patients. In our study, we aimed to investigate the prevalence of sleep disorders and the impact of these problems on the quality of life in cancer patients. Pittsburgh Sleep Quality Index (PSQI) was given to a total of 314 patients. The psychometric evaluation of the Turkish version of PSQI in cancer patients revealed that 127 (40.4%) patients had global PSQI scores >5, indicating poor sleep quality. There was no statistically significant relationship between PSQI scores and sexuality, marital status, cancer stage and chemotherapy type (P > 0.05); while the patients with bone and visceral metastasis had much lower PSQI scores (P = 0.006). Patients with Eastern Cooperative Oncology Group performance scores of 3 or more had also significantly lower PSQI scores (P = 0.02). In conclusion, PSQI questionnaire may be used to evaluate the sleep disorders in cancer patients. Consistent use of multi‐item measures such as PSQI with established reliability and validity would improve our understanding of difficulties experienced by cancer patients with chronic insomnia.     

Ischemia-modified albumin use as a prognostic factor in coronary bypass surgery

Background  

Various types of markers have been used so far in order to reveal myocardial perfusion defect. However, these markers usually appear in the necrosis phase or in the late stage. Having been the focus of various investigations recently, ischemia-modified albumin (IMA) is helpful in establishing diagnosis in the early stages of ischemia, before necrosis develops.     

Self-expanding covered metallic stent treatment of esophagojejunostomy fistulas

Purpose

The purpose of this study is to analyze the outcomes of the self-expanding covered metallic stent (SECMS) therapy in the management of the postoperative anastomotic leaks that seen after total gastrectomy–esophagojejunostomy (EJ) operations.

Materials and methods

Contrast radiography and endoscopy revealed EJ fistulas in 14 patients. SECMSs were implanted both fluoroscopically and endoscopically to seal fistulas. Postoperative fistula diagnosis times, postoperative covered stent implantation times, primary success rates, clinical success rates, postinterventional oral feeding beginning times, reduction of the drainage from the surgical drains, procedure-related mortality–morbidity, and mortality related with factors other than the procedure were noted.

Results

Technical success rate was 100 %. Clinical success rate was 79 %. Reduction of the fluid from surgical drains was observed in all patients. There were no procedure-related mortality. Recurrent fistula was observed in two patients (14 %) at the third and fifth day after the intervention. In one patient (7 %), stent dislocation was observed at the 10th day after the intervention. Non procedure-related mortality was 21 %. No anastomotic stricture, no in-stent stenosis was observed during the follow up period(11.09 ± 3.21 months).

Conclusion

From the above results we concluded that SECMS treatment for EJ fistulas is a safe, effective and technically easy procedure.     

Synthesis and antioxidant activity of new tetrahydro-naphthalene-indole derivatives as retinoid and melatonin analogs

A number of retinoid-related compounds represent classes of antioxidative and proapoptotic agents with promising potential in the treatment of neoplastic diseases. Indeed, the synthetic retinoid amide fenretinide [N-(4-hydroxyphenyl)retinamide] induces apoptosis of cancer cells and acts as a chemotherapeutic drug in cancer therapy. In the present work, and as a continuation of our studies on retinoid-type compounds, the synthesis of melatonin retinamide derivatives was studied as a novel series of melatonin retinoids, using the condensation reaction sequence involving tetrahydrotetramethylnaphthalene carboxylic acid and appropriate melatonin-type moieties. Despite of the weak DPPH inhibition activity pattern of the synthesized compounds, some of them showed a strong inhibition on lipid peroxidation (IVa-b, Va, and VIIa-c, 88, 96, 90, 94, 93, and 86%, respectively at 10(-4) M concentration) when melatonin (85% at 10(-4) M concentration) was used as a reference compound.     

Simultaneous coronary artery bypass grafting and ascending aorta to bifemoral bypass for ischemic heart disease combined with critical leg ischemia: case reports

Coronary artery disease may coexist with aortoiliac occlusive disease, and concomitant revascularization procedures may be required. The ascending aorta may be used as the source of inflow to both the femoral and coronary arteries in patients who present with coronary artery disease and critical leg ischemia. We present here 2 patients in whom coronary artery bypass grafting and ascending aorta-to-bifemoral bypass operations were performed simultaneously.