Time of Flight Secondary Ion Mass Spectrometric Determination of Molecular Weight Distributions of Low Polydispersity Poly(Dimethyl Siloxane) with Polyatomic Primary Ions

This work reports a comparison of oligomer and fragment ion intensities resulting from primary ion bombardment with several primary ion sources (Bin+, C60+, and Cs+) at various energies in secondary ion mass spectrometry (SIMS). Although the use of polyatomic primary ions are of great interest due to increased secondary ion efficiency and yield, we demonstrate that monatomic primary ions result in increased oligomer ion yield for polymers prepared as submonolayer films on silver substrates. The enhancement of oligomer secondary ion yield with monatomic ions is evidence that monatomic primary ions have a shallower sampling depth than polyatomic ions, resulting from a collision cascade that is less energetic at the sample surface. The results are also consistent with a lower degree of fragmentation of the resultant secondary ions, which is observed when evaluating the fragmentation data and the spectral data

Renal transplantation in a patient with Bartter syndrome and glomerulosclerosis

Bartter syndrome (BS) is a clinically and genetically heterogeneous inherited renal tube disorder characterized by renal salt wasting, hypokalemic metabolic alkalosis and normotensive hyperreninemic hyperaldosteronism. There have been several case reports of BS complicated by focal segmental glomerulosclerosis (FSGS). Here, we have reported the case of a BS patient who developed FSGS and subsequent end-stage renal disease (ESRD) and provided a brief literature review. The patient presented with classic BS at 3 months of age and developed proteinuria at 7 years. Renal biopsy performed at 11 years of age revealed a FSGS perihilar variant. Hemodialysis was initiated at 11 years of age, and kidney transplantation was performed at 16 years of age. The post-transplantation course has been uneventful for more than 3 years with complete disappearance of BS without the recurrence of FSGS. Genetic study revealed a homozygous p.Trp(TGG)610Stop(TGA) mutation in the CLCNKB gene. In summary, BS may be complicated by secondary FSGS due to the adaptive response to chronic salt-losing nephropathy, and FSGS may progress to ESRD in some patients. Renal transplantation in patients with BS and ESRD results in complete remission of BS

A Case of Wernicke's Encephalopathy Following Fluorouracil-based Chemotherapy

The pyrimidine antimetabolite 5-fluorouracil (5-FU) is a chemotherapeutic agent used widely for various tumors. Common side effects of 5-FU are related to its effects on the bone marrow and gastrointestinal epithelium. Neurotoxicity caused by 5-FU is uncommon, although acute and delayed forms have been reported. Wernicke's encephalopathy is an acute, neuropsychiatric syndrome resulting from thiamine deficiency, and has significant morbidity and mortality. Central nervous system neurotoxicity such as Wernicke's encephalopathy following chemotherapy with 5-FU has been reported rarely, although it has been suggested that 5-FU can produce adverse neurological effects by causing thiamine deficiency. We report a patient with Wernicke's encephalopathy, reversible with thiamine therapy, associated with 5-FU-based chemotherapy

Consumption of Oleic Acid During Matriphagy in Free-Living Nematodes Alleviates the Toxic Effects of the Bacterial Metabolite Violacein

Maternal behaviors benefit the survival of young, contributing directly to the mother's reproductive fitness. An extreme form of this is seen in matriphagy, when a mother performs the ultimate sacrifice and offers her body as a meal for her young. Whether matriphagy offers only a single energy-rich meal or another possible benefit to the young is unknown. Here, we characterized the toxicity of a bacterial secondary metabolite, namely, violacein, in Caenorhabditis elegans and found it is not only toxic towards adults, but also arrests growth and development of C. elegans larvae. To counteract this, C. elegans resorted to matriphagy, with the mothers holding their eggs within their bodies and hatching the young larvae internally, which eventually led to the mothers' death. This violacein-induced matriphagy alleviated some of the toxic effects of violacein, allowing a portion of the internally-hatched young to bypass developmental arrest. Using genetic and pharmacological experiments, we found the consumption of oleate, a monounsaturated fatty acid produced by the mother, during matriphagy is partially responsible. As such, our study provides experimental evidence of why such a drastic and peculiar maternal behavior may have arisen in nematode natural habitats

Unconventional assemblies of bisacylhydrazones: The role of water for circularly polarized luminescence

Understanding the precise molecular arrangement of chiral supramolecular polymers is essential not only to comprehend complex superstructures like proteins and DNA but also for the development of next-generation optoelectronic materials, including materials displaying high-performance circularly polarized luminescence (CPL). Herein, we report the first chiral supramolecular polymer systems based on hydrazone???pyridinium conjugates comprising alkyl chains of different lengths, which afforded control of the apparent supramolecular chirality. Although supramolecular chirality is governed basically by the remote chiral centers of alkyl chains, helicity inversion was achieved by controlling the conditions under which the hydrazone building blocks underwent aggregation (i.e., solvent compositions or temperature). More importantly, the addition of water to the system led to aggregation-induced hydrazone deprotonation, which resulted in a completely different self-assembly behavior. Structural water molecules played an essential role, forming the assembly's channel-like backbone, around which hydrazone molecules gathered as a result of hydrogen bonding interactions. Further co-assembly of an achiral hydrazone luminophore with the given supramolecular polymer system allowed the fabrication of a novel CPL-active hydrazone-based material exhibiting a high maximum value for the photoluminescence dissymmetry factor of ???2.6 ?? 10???2

The outcome of percutaneous stent implantation in congenital heart disease: experience of a single institute

PurposeThe efficacy of percutaneous stent implantation for congenital heart disease (CHD) in Korea, where stent availability is limited, has not been determined. This study evaluated the acute and midterm results of stent implantation in different CHD subgroups.MethodsStents were implanted in 75 patients with 81 lesions: (1) pulmonary artery stenosis (PAS) group, 56 lesions in 51 patients; (2) coarctation of the aorta (CoA) group, 5 lesions in 5 patients; (3) Fontan group, 13 lesions in 12 patients; (4) ductal stent group, 3 lesions in 3 patients; and (5) other CHD group, 4 lesions in 4 patients. Mean follow-up duration was 2.1 years (0.1–4 years). Medical records were reviewed retrospectively.ResultsThe minimum lumen diameter (MLD) in PAS and CoA increased from 5.0±1.9 mm and 8.4±1.6 mm to 10.1±3.6 mm and 12.3±2.5 mm, respectively (P<0.01). In the PAS group, pressure gradient decreased from 25.7±15.6 mmHg to 10.4±10.1 mmHg, and right ventricular to aortic pressure ratio from 0.56±0.21 to 0.46±0.19. In the CoA group, the pressure gradient decreased from 50±33 mmHg to 17±8 mmHg. In the ductal stent group, the MLD of the ductus increased from 2.3 mm to 4.3 mm and arterial oxygen saturation from 40%–70% to 90%. No deaths were associated with stent implantation. Stent migration occurred in 3 patients, but repositioning was successful in all. Stent redilation was performed successfully in 26 cases after 29±12 months.ConclusionPercutaneous stent implantation was safe and effective, with acceptable short and mid-term outcomes in Korean CHD patients

Neutrophilia is more predictive than increased white blood cell counts for short-term mortality after liver transplantation in patients with acute-on-chronic liver failure

Background Acute-on-chronic liver failure (ACLF) is a life-threatening disease that requires urgent liver transplantation (LT). Accurate identification of high-risk patients is essential for predicting post-LT survival. The chronic liver failure consortium ACLF score is a widely accepted risk-stratification score that includes total white blood cell (WBC) counts as a component. This study aimed to evaluate the predictive value of total and differential WBC counts for short-term mortality following LT in patients with ACLF. Methods A total of 685 patients with ACLF who underwent LT between January 2008 and February 2019 were analyzed. Total and differential WBC counts were examined as a function of the model for end-stage liver disease for sodium (MELD-Na) score. The association between total and differential WBC counts and 90-day post-LT mortality was assessed using multivariable Cox proportional hazards regression analysis. Results The total WBC counts and neutrophil ratio were higher in patients with ACLF than in those without ACLF. The neutrophil ratio was significantly associated with 90-day post-LT mortality after adjustment (hazard ratio [HR], 1.04; P = 0.001), whereas total WBC counts were not significantly associated with 90-day post-LT mortality in either univariate or multivariate Cox analyses. The neutrophil ratio demonstrated a relatively linear trend with an increasing MELD-Na score and HR for 90-day post-LT mortality, whereas the total WBC counts exhibited a plateaued pattern. Conclusions Neutrophilia, rather than total WBC counts, is a better prognostic indicator for short-term post-LT mortality in patients with ACLF