Statistical Copolymers of N-Vinylpyrrolidone and Isobornyl Methacrylate via Free Radical and RAFT Polymerization: Monomer Reactivity Ratios, Thermal Properties, and Kinetics of Thermal Decomposition.

The synthesis of statistical copolymers of N-vinylpyrrolidone (NVP) with isobornyl methacrylate (IBMA) was conducted by free radical and reversible addition-fragmentation chain transfer (RAFT) polymerization. The reactivity ratios were estimated using the Finemann-Ross, inverted Fineman-Ross, Kelen-Tüdos, extended Kelen-Tüdos and Barson-Fenn graphical methods, along with the computer program COPOINT, modified to both the terminal and the penultimate models. According to COPOINT the reactivity ratios were found to be equal to 0.292 for NVP and 2.673 for IBMA for conventional radical polymerization, whereas for RAFT polymerization and for the penultimate model the following reactivity ratios were obtained: r11 = 4.466, r22 = 0, r21 = 14.830, and r12 = 0 (1 stands for NVP and 2 for IBMA). In all cases, the NVP reactivity ratio was significantly lower than that of IBMA. Structural parameters of the copolymers were obtained by calculating the dyad sequence fractions and the mean sequence length. The thermal properties of the copolymers were studied by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and differential thermogravimetry (DTG). The results were compared with those of the respective homopolymers.

Oesophageal atresia without major cardiovascular anomalies: Is management justified at a district paediatric surgical institution?

BACKGROUND: Oesophageal atresia lacks sufficiently documented treatment approach, as guidelines are based rather on the opinion of experts than on systematic data. We aimed to answer the question if treatment of patients without major cardiovascular anomalies could be justified at a peripheral paediatric surgical institution, by evaluating the outcome of surgical correction. METHODS: Thirty-three neonates underwent surgery for correction of oesophageal atresia during a period of 20 years. They were categorised into two time-period groups, to follow-up the evolution of surgical intervention and complications through time. Evaluation of post-operative outcome and morbidity was performed. The results were related to those of our recent cross-sectional study on families having experienced oesophageal atresia performed years after repair, regarding the long-term quality of life. RESULTS: A shift from staged to primary repair occurred throughout time in the patients with a marginal long gap between proximal and distal oesophagus (P = 0.008). Anastomotic stenosis was the major short-term complication encountered, treated with post-operative dilation sessions. Dysphagia and reflux were the most common long-term complications. CONCLUSIONS: Oesophageal atresia without severe cardiovascular abnormalities could be treated at a peripheral paediatric surgical department with satisfactory outcomes. However, qualified paediatric surgeons, anaesthesiologists and neonatologists and the availability of neonatal intensive care unit should be definitively required.

Predictive model of heterotopy in Meckel's diverticulum in children.

BACKGROUND: The presence of heterotopic tissue in Meckel's diverticulum (MD) increases the incidence of future complications. Based on this concept, this study aimed to detect clinical and morphological parameters able to predict the probability of heterotopy in incidentally discovered uncomplicated MD and to develop a risk-based classification tool. METHODS: The clinical records of 146 patients who underwent MD resection were reviewed. MD complications (bleeding, inflammation, perforation or involvement in pathological processes such as intussusception) and MD dimensions (width, length and the product width × length) were evaluated in association with heterotopy. Regression analysis was used to explore the discrete effect of clinically relevant parameters, which were subsequently combined in a Classification and Regression Tree. RESULTS: The probability of heterotopy was higher in complicated MDs. The width of the base of the MD and the product width × length were also significant predictors of heterotopy. A stepwise combination (Classification and Regression Tree model) of (i) uncomplicated macroscopic presentation, (ii) width <2.5 cm, (iii) age <10 years and (iv) product width × length <4 cm2 resulted in a null probability of heterotopy in our study group. CONCLUSION: The combination of MD-related clinical and morphological parameters using advanced statistical tools may assist in estimating the probability of heterotopy. This may be applied in incidentally discovered uncomplicated MDs during abdominal surgery for other morbidities. Prospective studies are required to confirm our findings and test the practical usefulness of the classification tool developed here.

Evaluation of the detection of GBA missense mutations and other variants using the Oxford Nanopore MinION.

BACKGROUND: Mutations in GBA cause Gaucher disease when biallelic and are strong risk factors for Parkinson's disease when heterozygous. GBA analysis is complicated by the nearby pseudogene. We aimed to design and validate a method for sequencing GBA using long reads. METHODS: We sequenced GBA on the Oxford Nanopore MinION as an 8.9 kb amplicon from 102 individuals, including patients with Parkinson's and Gaucher diseases. We used NanoOK for quality metrics, NGMLR to align data (after comparing with GraphMap), Nanopolish and Sniffles to call variants, and WhatsHap for phasing. RESULTS: We detected all known missense mutations in these samples, including the common p.N409S (N370S) and p.L483P (L444P) in multiple samples, and nine rarer ones, as well as a splicing and a truncating mutation, and intronic SNPs. We demonstrated the ability to phase mutations, confirm compound heterozygosity, and assign haplotypes. We also detected two known risk variants in some Parkinson's patients. Rare false positives were easily identified and filtered, with the Nanopolish quality score adjusted for the number of reads a very robust discriminator. In two individuals carrying a recombinant allele, we were able to detect and fully define it in one carrier, where it included a 55-base pair deletion, but not in another one, suggesting a limitation of the PCR enrichment method. Missense mutations were detected at the correct zygosity, except for the case where the RecNciI one was missed. CONCLUSION: The Oxford Nanopore MinION can detect missense mutations and an exonic deletion in this difficult gene, with the added advantages of phasing and intronic analysis. It can be used as an efficient research tool, but additional work is required to exclude all recombinants.

An Uncommon Case of Cervical Thymopharyngeal Duct Cyst.

Thymopharyngeal duct cyst is one of the most uncommon benign cervical lesions encountered in the paediatric population. Due to its rarity, it almost always escapes a correct preoperative diagnosis and is usually misdiagnosed as a branchial cyst or lymphangioma. Furthermore, although located at the neck it may present with retrosternal or mediastinal extension. In this case report here we present a case of a young boy with a right cervical mass, diagnosis of thymopharyngeal duct cyst was confirmed during histopathological examination of the excised specimen. Furthermore, preoperative ultrasonography and MRI did not detect the thin cord and the lower part of the lesion, which rendered operative treatment more demanding. Apropos to these findings, we reflect on the crucial points of awareness that affect the diagnostic and surgical process of this lesion.

Greek renal nurses' attitudes towards death.

UNLABELLED: This study aims to assess how Greek renal nurses feel about death and examine any relationships between their attitudes and demographic factors. DESIGN: Descriptive quantitative study. The sample comprised of 49 nurses. METHODOLOGY: Voluntary and anonymous completion of the Death Attitude Profile-Revised and a demographic questionnaire. RESULTS: 44 respondents were female and 5 were male with a mean age of 25.80 years. The mean nursing experience was 10.9 years. Nursing experience and age were the variables most likely to predict nurses' attitudes towards death. Nurses with specific education on palliative care had less difficulty talking about death and dying and did not have a fear of death. The Hospital-based teams (known as palliative care teams, supportive care teams or symptom assessment teams) had statistically significant different relationships with fear of death and neutral acceptance scores. CONCLUSIONS: It is recommended to include education on death and care of the dying in the nursing degree course in order for nurses who are giving terminal phase patient care to be better able deal with issues that death evolves.