Swallow-induced esophageal shortening in patients without hiatal hernia is associated with gastroesophageal reflux

Longitudinal esophageal body shortening with swallow-induced peristalsis has been reported in healthy individuals. Esophageal shortening is immediately followed by esophageal re-elongation, and the lower esophageal sphincter (LES) returns to the baseline position. High-resolution manometry (HRM) allows for objective assessment of extent of shortening and duration of shortening. In patients without hiatal hernia at rest, swallow-induced esophageal shortening can lead to transient hiatal hernia (tHH) which at times may persist after the completion of swallow. This manometric finding has not been investigated in the literature, but a question arises whether this swallow-induced transient herniation can effect on the likelihood of gastroesophageal reflux. This study aims to assess the relationship between gastroesophageal reflux and the subtypes of swallow-induced esophageal shortening, i.e. tHH and non-tHH, in patients without hiatal hernia at rest. After Institutional Review Board (IRB) approval, we queried a prospectively maintained database to identify patients who underwent HRM evaluation and 24-hour pH study between January to December 2015. Patients with type-I esophagogastric junction (EGJ) morphology (i.e. no hiatal hernia) according to the Chicago classification v3.0 were included. The patterns of the esophageal shortening with swallows were divided into two subtypes, i.e. tHH and non-tHH. tHH was defined as an EGJ double high-pressure zones (≥1 cm) at the second inspiration after the termination of swallow-induced esophageal body contraction. The number of episodes of tHH was counted per 10 swallows and tHH size was measured for each patient. In total, 41 patients with EGJ morphology Type-I met the inclusion criteria. The mean age was 47.2 years, 35 patients (85.4%) were women, and the mean body mass index was 33.9 kg/m2. The mean number of tHH episodes was 3 out of 10 swallows; mean maximal tHH size was 1.3 cm. Patients who had tHH in ≥3 out of 10 swallows (n = 16; 39.0%) were more likely to have abnormal DeMeester scores than patients with <3 swallows (56% vs. 28%; P = 0.070). Patients with maximal tHH ≥2 cm in at least 1 swallow (n = 17; 41.5%) were more likely to experience pathological reflux than patients with maximal tHH <2 cm (59% vs. 25%; P = 0.029). In conclusion, we showed that, in a subset of patients with Type-I EGJ morphology, swallowing induced transient EGJ double high-pressure zones (≥1 cm) after peristalsis. We have named this new manometric finding the swallow-induced tHH. A high prevalence of pathological reflux disease was observed in patients with maximal tHH ≥2 cm. The degree of swallow-induced tHH could be an early indicator of lower esophageal sphincter dysfunction in patients without manometric hiatal hernia.

Low temperature magnetic properties of Nd2Ru2O7

We present magnetic susceptibility, heat capacity, and neutron diffraction measurements of polycrystalline Nd₂Ru₂O₇ down to 0.4 K. Three anomalies in the magnetic susceptibility measurements at 146, 21 and 1.8 K are associated with an antiferromagnetic ordering of the Ru⁴⁺ moments, a weak ferromagnetic signal attributed to a canting of the Ru⁴⁺ and Nd³⁺ moments, and a long-range-ordering of the Nd³⁺ moments, respectively. The long-range order of the Nd³⁺ moments was observed in all the measurements, indicating that the ground state of the compound is not a spin glass. The magnetic entropy of Rln2 accumulated up to 5 K, suggests the Nd³⁺ has a doublet ground state. Lattice distortions accompany the transitions, as revealed by neutron diffraction measurements, and in agreement with earlier synchrotron x-ray studies. The magnetic moment of the Nd³⁺ ion at 0.4 K is estimated to be 1.54(2)µ _B and the magnetic structure is all-in all-out as determined by our neutron diffraction measurements.

Improved On-Line Thoracic Duct Drainage for Lymphocytapheresis

Lymphocytapheresis using thoracic duct drainage (TDD) is a recognized technique of extracorporeal immunomodulation for various autoimmune diseases such as rheumatoid arthritis (RA), and its clinical benefit has been reported and generally accepted. Lymphocytapheresis using TDD is very selective for removing lymphocytes (especially helper T-cells) but raises some problems such as hypoproteinemia due to the massive removal of lymph, and difficulties in repeated treatment. Along with the development of a new polyester fiber filter, we have developed a simple and effective method of lymphocytapheresis for wide adoption for these techniques. We performed lymphocytapheresis using TDD in patients with RA and previously reported its clinical efficacy indicated by the significantly lower number of peripheral lymphocytes and T4/T8 ratio. We present here our newly-developed on-line system designed to prevent hypoproteinemia. Furthermore we report on the advantages with a new subcutaneous vascular access device set up to manage the problems of repeated treatments. A small reservoir for keeping the thoracic duct open and returning lymph to the patient permitted sufficient lymph drainage and removal of lymphocytes and the clinical application of TDD is discussed.

Abstract P2-09-33: Not presented

This abstract was not presented at the symposium.

Diel regulation of photosynthetic activity in the oceanic unicellular diazotrophic cyanobacterium Crocosphaera watsonii WH8501

The oceanic unicellular diazotrophic cyanobacterium Crocosphaera watsonii WH8501 exhibits large diel changes in abundance of both Photosystem II (PSII) and Photosystem I (PSI). To understand the mechanisms underlying these dynamics, we assessed photosynthetic parameters, photosystem abundance and composition, and chlorophyll-protein biosynthesis over a diel cycle. Our data show that the decline in PSII activity and abundance observed during the dark period was related to a light-induced modification of PSII, which, in combination with the suppressed synthesis of membrane proteins, resulted in monomerization and gradual disassembly of a large portion of PSII core complexes. In the remaining population of assembled PSII monomeric complexes, we detected the non-functional version of the D1 protein, rD1, which was absent in PSII during the light phase. During the dark period, we also observed a significant decoupling of phycobilisomes from PSII and a decline in the chlorophyll a quota, which matched the complete loss of functional PSIIs and a substantial decrease in PSI abundance. However, the remaining PSI complexes maintained their photochemical activity. Thus, during the nocturnal period of nitrogen fixation C. watsonii operates a suite of regulatory mechanisms for efficient utilization/recycling of cellular resources and protection of the nitrogenase enzyme.

Angiopoietin-like protein 2 promotes chondrogenic differentiation during bone growth as a cartilage matrix factor

OBJECTIVE

Chondrocyte differentiation is crucial for long bone growth. Many cartilage extracellular matrix (ECM) proteins reportedly contribute to chondrocyte differentiation, indicating that mechanisms underlying chondrocyte differentiation are likely more complex than previously appreciated. Angiopoietin-like protein 2 (ANGPTL2) is a secreted factor normally abundantly produced in mesenchymal lineage cells such as adipocytes and fibroblasts, but its loss contributes to the pathogenesis of lifestyle- or aging-related diseases. However, the function of ANGPTL2 in chondrocytes, which are also differentiated from mesenchymal stem cells, remains unclear. Here, we investigate whether ANGPTL2 is expressed in or functions in chondrocytes.

METHODS

First, we evaluated Angptl2 expression during chondrocyte differentiation using chondrogenic ATDC5 cells and wild-type epiphyseal cartilage of newborn mice. We next assessed ANGPTL2 function in chondrogenic differentiation and associated signaling using Angptl2 knockdown ATDC5 cells and Angptl2 knockout mice.

RESULTS

ANGPTL2 is expressed in chondrocytes, particularly those located in resting and proliferative zones, and accumulates in ECM surrounding chondrocytes. Interestingly, long bone growth was retarded in Angptl2 knockout mice from neonatal to adult stages via attenuation of chondrocyte differentiation. Both in vivo and in vitro experiments show that changes in ANGPTL2 expression can also alter p38 mitogen-activated protein kinase (MAPK) activity mediated by integrin α5β1.

CONCLUSION

ANGPTL2 contributes to chondrocyte differentiation and subsequent endochondral ossification through α5β1 integrin and p38 MAPK signaling during bone growth. Our findings provide insight into molecular mechanisms governing communication between chondrocytes and surrounding ECM components in bone growth activities.