Tweety-homolog (Ttyh) Family Encodes the Pore-forming Subunits of the Swelling-dependent Volume-regulated Anion Channel (VRAC(swell)) in the Brain

In the brain, a reduction in extracellular osmolality causes water-influx and swelling, which subsequently triggers Cl⁻- and osmolytes-efflux via volume-regulated anion channel (VRAC). Although LRRC8 family has been recently proposed as the pore-forming VRAC which is activated by low cytoplasmic ionic strength but not by swelling, the molecular identity of the pore-forming swelling-dependent VRAC (VRAC(swell)) remains unclear. Here we identify and characterize Tweety-homologs (TTYH1, TTYH2, TTYH3) as the major VRAC(swell) in astrocytes. Gene-silencing of all Ttyh1/2/3 eliminated hypo-osmotic-solution-induced Cl⁻ conductance (I(Cl,swell)) in cultured and hippocampal astrocytes. When heterologously expressed in HEK293T or CHO-K1 cells, each TTYH isoform showed a significant I(Cl,swell) with similar aquaporin-4 dependency, pharmacological properties and glutamate permeability as I(Cl,swell) observed in native astrocytes. Mutagenesis-based structure-activity analysis revealed that positively charged arginine residue at 165 in TTYH1 and 164 in TTYH2 is critical for the formation of the channel-pore. Our results demonstrate that TTYH family confers the bona fide VRAC(swell) in the brain.

Neuronal Expression and Cell-Type-Specific Gene-Silencing of Best1 in Thalamic Reticular Nucleus Neurons Using pSico-Red System

Assessing the cell-type expression pattern of a certain gene can be achieved by using cell-type-specific gene manipulation. Recently, cre-recombinase-dependent gene-silencing tool, pSico has become popular in neuroscientific research. However, pSico has a critical limitation that gene-silenced cell cannot be identified by fluorescence, due to an excision of the reporter gene for green fluorescence protein (GFP). To overcome this limitation, we newly developed pSico-Red, with mCherry gene as a reporter outside two loxP sites, so that red mCherry signal is detected in all transfected cells. When a cell expresses cre, GFP is excised and shRNA is enabled, resulting in disappearance of GFP. This feature of pSico-Red provides not only cell-type-specific gene-silencing but also identification of cre expressing cells. Using this system, we demonstrated for the first time the neuronal expression of the Bestrophin-1 (Best1) in thalamic reticular nucleus (TRN) and TRN-neuron-specific gene-silencing of Best1. We combined adeno-associated virus (AAV) carrying Best1-shRNA in pSico-Red vector and transgenic mouse expressing cre under the promoter of distal-less homeobox 5/6 (DLX5/6), a marker for inhibitory neurons. Firstly, we found that almost all of inhibitory neurons in TRN express Best1 by immunohistochemistry. Using pSico-Red virus, we found that 80% of infected TRN neurons were DLX5/6-cre positive but parvalbumin negative. Finally, we found that Best1 in DLX5/6-cre positive neurons were significantly reduced by Best1-shRNA. Our study demonstrates that TRN neurons strongly express Best1 and that pSico-Red is a valuable tool for cell-type-specific gene manipulation and identification of specific cell population.

Historical Study of the Etymological Form and Translational Process of Gout (Tongfeng) / 의사학

This study aims to address questions regarding the translation of 'gout' into 'tongfeng' in East Asia. To this end, the formation process of the origins, 'gout' from Western medicine and 'tongfeng' from Oriental medicine, and the translational process were investigated through the relevant records and literature dating from the 16th century on. Symptoms associated with gout were originally mentioned in ancient Egypt and various terminologies were used to refer to gout, such as podagra, cheiragra and gonogra. The word 'gout', which is derived from Latin, was used for the first time in the 13th century. The reason for this linguistic alteration is thought to be the need for a comprehensive term to cover the various terms for gout in symptomatic body parts, since it can occur concurrently in many joints. However, it took hundreds of years before gout was independently established as a medical term. In oriental medicine, terms describing diseases with features similar to gout include bibing, lijiefeng, baihufeng and tongfeng. Among them, the concept of 'tongfeng' has been established since the Jin and Yuan dynasties. The cause, prevention and various treatments for tongfeng were proposed throughout the Ming and Qing dynasties. The early translation of gout and tongfeng in East Asia, respectively, is estimated to have occurred in the 18th century. The first literature translating gout in China was 'An English and Chinese Vocabulary in the Court Dialect (yinghua yunfu lijie)'. From the publication of this book until the late 19th century, gout was translated into an unfamiliar Chinese character 'Jiu feng jiao', likely because the translation was done mostly by foreign missionaries at the time, and they created a new word on the basis of Western medicine instead of researching and translating similar diseases in oriental medicine. In Japan, the first book translating gout was 'A Pocket Dictionary of the English and Japanese Language (Eiwa taiyaku shuchin jisho)', Japan's the first English-Japanese translation dictionary. In this book, gout was translated into tongfeng, a word adopted from oriental medicine. These differences from China are thought to be caused by Rangaku doctors, who, influenced by oriental medicine in the Jin and Yuan dynasties, played an important role in translating medical terminology at that time.

The Influence of Donguibogam during the Middle Joseon Era Based on Clinical Records on Low Back Pain in Seungjeongwon ilgi / 의사학

The recently increasing interest in historical records has led to more research on historical records in various fields of study. This trend has also affected medical research, with the medical climate and popular treatment modalities of the past now being revealed based on historical records. However, most research on medical history during the Joseon era has been based on the most well-known record, Joseon wangjo sillok or Annals of the Joseon Dynasty. Joseon wangjo sillok is a comprehensive and organized record of society during the Joseon era and contains key knowledge about medical history during the period, but it lacks details on the treatment of common disorders at the time. Seungjeongwon ilgi or Diary of the Royal Secretariat has detailed records of daily events and is a valuable resource for the daily activities of the era. And in the middle Josoen era, a variety of medical books - especially Donguibogam - was published. Therefore, the authors focused on the under-researched Seungjeongwon ilgi, Donguibogam and attempted to assess and evaluate low back pain treatment performed on Joseon royalty. The most notable characteristic of low back treatment records within the Seungjeongwon ilgi is that diagnosis and treatment was made based on an independent Korean medicine, rather than conventional Chinese medicine. This paradigm shift is represented in Dongeuibogam, and can be seen in the close relationship between Dongeuibogam and national medical exams of the day. Along with the pragmatism of the middle Joseon era, medical treatment also put more focus on pragmatic treatment methods, and records show emphasis on acupuncture and moxibustion and other points in accord with this. The authors also observed meaning and limitations of low back pain treatment during that era through comparison with current diagnosis and treatment.

Expression of hMSH2, hMLH1 Protein in Sporadic Colorectal Cancer and Corresponding Normal Tissue

PURPOSE: DNA mismatch repair gene is responsible for hereditary nonpolyposis colorectal cancer. But it is not well known its role in sporadic colorectal cancer patients. We analysed normal hMSH2, hMLH1 protein expression in colorectal adenocarcinoma tissues and corresponding normal tissues to find out the role of mismatch repair gene in sporadic colorectal cancer by Western blotting. METHODS: Normal hMSH2 and hMLH1 protein expression was studied on 25 colorectal cancer and corresponding normal tissue by Western blot with hMSH2 and hMLH1 monoclonal antibody. Normal protein band was expressed on 100 kD in hMSH2 and 87 kD in hMLH1. SW480 and LoVo cell line was used as positive and negative control for hMSH2 and LoVo and SW480 as positive and negative for hMLH1. And we analysed the relation between the hMSH2, hMLH1 protein expression and clinicopathological parameters. RESULTS: It was 2 cases (8%) that both hMSH2 and hMLH1 protein expression was not observed. Three cases (12%) were negative for hMSH2 and 2 cases (8%) for hMLH1. One or both hMSH2, hMLH1 protein expression was not observed in 7 cases (28%) in total. There was no correlation for proximal occurrence (25% vs 35%), young age (37.5% vs 23.5%) and lymph node metastasis (50% vs 47%). But poorly and mucinous differentiation was regarded as having relation with negative expression of hMSH2 and hMLH1 (50% vs 17.6%) but not significant statistically. CONCLUSION: Sporadic colorectal cancer with negative expression of normal hMSH2 and hMLH1 protein showed no relation to younger age, proximal site preference and lymph node metastasis. But it was suggested that mismatch repair gene protein was involved in cancer cell differentiation in sporadic colorectal cancer.