Decreased Memory and Learning Ability Mediated by Bmal1/M1 Macrophages/Angptl2/Inflammatory Cytokine Pathway in Mice Exposed to Long-Term Blue Light Irradiation.

Humans are persistently exposed to massive amounts of blue light via sunlight, computers, smartphones, and similar devices. Although the positive and negative effects of blue light on living organisms have been reported, its impact on learning and memory remains unknown. Herein, we examined the effects of widespread blue light exposure on the learning and memory abilities of blue light-exposed mice. Ten-week-old male ICR mice were divided into five groups (five mice/group) and irradiated with blue light from a light-emitting diode daily for 6 months. After 6 months of blue light irradiation, mice exhibited a decline in memory and learning abilities, assessed using the Morris water maze and step-through passive avoidance paradigms. Blue light-irradiated mice exhibited a decreased expression of the clock gene brain and muscle arnt-like 1 (Bmal1). The number of microglia and levels of M1 macrophage CC-chemokine receptor 7 and inducible nitric oxide synthase were increased, accompanied by a decrease in M2 macrophage arginase-1 levels. Levels of angiopoietin-like protein 2 and inflammatory cytokines interleukin-6, tumor necrosis factor-α, and interleukin-1ß were elevated. Our findings suggest that long-term blue light exposure could reduce Bmal1 expression, activate the M1 macrophage/Angptl2/inflammatory cytokine pathway, induce neurodegeneration, and lead to a decline in memory.

[The Strength of the Sense of Shame of the Aged in Care Scenes: Comparison Between Whether or not There is Anyone Else Around Them].

Medical staff in a hospital or nursing facility should take care of aged individuals with dignity and respect. We conducted a survey on aged individuals to derive under what care circumstances they had a sense of shame, using 12 illustrations, drawn by ourselves, which were common daily care scenes where nurses and patients meet. This survey was conducted at 4 care facilities in A prefecture, Japan. The number of surveyed persons was 43, with the following exclusion criteria: over 60 years old, more than third level of care needed, and non suspected of having dementia. We got the following results from the answers of 41 persons: 1. When elder persons are surrounded by people other than the care staff, they feel more of a sense of shame than when alone; 2. They feel more sense of shame when they use a wheelchair than when they use crutches; 3. They do not feel much shame when they get a bed-bath, even if other persons are there; and 4. Male patients feel more shame than females when they meet their family. These results suggest that elderly patients feel a stronger sense of shame when they are seen by others than when they are seen by care staff. The result 2 suggests that the use of a wheelchair exposes their physical weakness to others. Males feel a stronger sense of shame when they show a weakness in their gender role. We conclude that the sense of shame of aged individuals in daily life scenes in a care facility depends on their gender and whether or not they are surrounded by other persons.

[Nursing Care Students' Image of Shame -Comparison Between First and Second Year Nursing Students].

It is not easy for nurses to estimate a patient's degree of shame, as the sense of shame depends on each person's personality, but nurses are requested to evaluate it as correctly as possible and to reduce the patient's mental load. We presume that most of the sense of shame is generated by body defects or disadvantages recognized by the patient. In this study, we tried to measure the degree of shame and to improve the basic nursing curriculum, depending on students' school year, under the assumption of what cases the nurses would frequently meet in a hospital. We prepared 13 figures that show common cases in hospitals. In these figures: 1) 6 figures show cases in which a nurse touched a patient's body; 2) 3 figures show common daily life; and 3) 4 figures show cases in which there are other people around the patient. A questionnaire was given to the first and second year students in A Nursing University, and we allocated scores of 1 to 10: 1 is "no-shame", and 10 is "very much shame". The students answered that patients must feel shame when: 1) they take off their clothes, 2) they show their disability to another person even without taking their clothes off, and 3) having people other than medical staff around them. In the results, as 2) appeared more strongly in the second year students than in the first, we thought that the second year students could surmise a patient's position in a hospital through the effect of the nursing education.

Development of Teaching Materials in Basic Nursing Using Virtual Reality －Ceiling Image Teaching Materials of a Hospital Room－.

It is difficult to understand nursing practically for students who have just started studying nursing, because they cannot imagine the actual medical scene. The authors expect that they can improve nursing learning through experiences in virtual medical environments supported by ICT (information and commnication technology). We developed teaching materials in nursing education, and in a previous study we reported that the use of a virtual hospital was useful for students who had not had medical experience. The aim of the present study was to have students consider the meaning of a hospital room ceiling. First, we showed them a few ceiling patterns, and they selected the best one among the patterns. After that, we showed the same one in a virtual hospital room. They had negative opinions about what they had thought was the best one at this time. This demonstrates that the virtual hospital room is effective when students evaluate the ceiling as a part of the hospital room.

Nursing Education Trial Using a Virtual Nightingale Ward.

Nursing department students are expected to correctly grasp the entire concept of nursing through their education. The authors created a movie of a Nightingale ward (virtual ward, hereafter) with an architectural computer design software for education. The students' reaction to the virtual ward was categorized into three viewpoints: that of nurses, of patients, and of nurses and patients in common. Most of the reactions in each viewpoint were: "easy to observe patients" in the nurses' viewpoint; "no privacy" in the patients' viewpoint; and "wide room" in the common viewpoint, respectively. These reactions show the effectiveness of using a virtual ward in nursing education. Because these reactions are characteristics of a Nightingale ward, and even students, who have generally less experiences, recognized these characteristics from the both viewpoints of nurses and patients.

[Nursing Education Utilizing Experiences in a Virtual Hospital Ward].

Environmental design should be required at medical facilities for conducting medical practice safely and for making hospitalization comfortable. Many medical nursing students cannot imagine medical facilities, especially hospital wards, when they study medical environments in a basic nursing lecture. As a result, they cannot connect well with patient assistance. We employed a computer assisted designing software, "3D My Home Designer" (Mega Soft Company) that runs on Windows 8, and considered the usefulness of it for lectures on environmental design showing how to design a hospital ward for patients' optimal hospital stay. We drew a medical facility in 2-D first, transformed it into 3D images, and then created movies of a virtual hospital ward in which a patient walked around. These movies consisted of 3 kinds: a) hospital room with changeable wall color, b) different allocations of hospital room and nurse station, and c) a blurred ward which corresponded to how a patient with poor eyesight (cataract) would see a ward. We prepared as controls: a') still images of a hospital room, b') still images of ward, and c') a documentation on how a ward is seen by a patient with a cataract. We gave a questionnaire to students and nurses about these movies and still images (controls). In a) and b), there were no differences between the movies and still images in both students and nurses. In c), both students and nurses had a viewpoint from the patient with poor eyesight. From these results, we consider that the students, who have fewer experiences in a hospital, may understand the environments well by movies and the application of a virtual movie ward to nursing education may be useful in a lecture, depending on the readiness of the students.

[Evaluation of Educational Effect of Problem-Posing System in Nursing Processing Study].

The nursing processing study is generally difficult, because it is important for nursing college students to understand knowledge and utilize it. We have developed an integrated system to understand, utilize, and share knowledge. We added a problem-posing function to this system, and expected that students would deeply understand the nursing processing study through the new system. This system consisted of four steps: create a problem, create an answer input section, create a hint, and verification. Nursing students created problems related to nursing processing by this system. When we gave a lecture on the nursing processing for second year students of A university, we tried to use the creating problem function of this system. We evaluated the effect by the number of problems and the contents of the created problem, that is, whether the contents consisted of a lecture stage or not. We also evaluated the correlation between those and regular examination and report scores. We derived the following: 1. weak correlation between the number of created problems and report score (r=0.27), 2. significant differences between regular examination and report scores of students who created problems corresponding to the learning stage, and those of students who created problems not corresponding to it (P<0.05). From these results, problem-posing is suggested to be effective to fix and utilize knowledge in the lecture of nursing processing theory.

Induction of Skin Cancer by Long-Term Blue Light Irradiation.

Presently, people are not only exposed to sunlight but also to a large amount of blue light from personal computers and smartphones. This blue light has various effects on the living body. However, its effect on the induction of skin cancer is unknown. In this study, we investigated the induction of skin cancer by long-term blue light irradiation. Hairless mice were irradiated with blue light (LED; peak emission 479 nm) every day for one year, and a control was irradiated with white light (LED), green light (LED; peak emission 538 nm), and red light (LED; peak emission 629 nm) for one year, respectively. Skin cancer was induced only in the mice exposed to blue light. Long-term blue light irradiation also increased the migration of neutrophils and macrophages involved in carcinogenesis in the skin. In neutrophils, an increased expression of citH3 and PAD4 was observed, suggesting the possibility of NETosis. Conversely, in macrophages, inflammatory macrophages (type 1 macrophages) increased and anti-inflammatory macrophages (type 2 macrophages) decreased due to continuous blue light irradiation. These findings suggest that long-term continuous irradiation with blue light induces neutrophil NETosis and an increase in type 1 macrophages, resulting in skin cancer.

The Effect of Bacillus coagulans Induced Interactions among Intestinal Bacteria, Metabolites, and Inflammatory Molecules in Improving Natural Skin Aging.

BACKGROUND: Lactic acid bacteria consumption serves several health benefits to humans. However, their effect on natural skin aging is still unclear. METHODS: This study examined the effects of skin naturalization (particularly skin drying) by administering a spore-bearing lactic acid bacteria (Bacillus coagulans) in mice for 2 years. RESULTS: B. coagulans administration improved the natural skin of mice and significantly increased proportions of the genera Bacteroides and Muribaculum, among other intestinal bacteria. As metabolites, increases in nicotinic acid, putrescin, and pantothenic acid levels and a decrease in choline levels were observed. Increased hyaluronic acid, interleukin-10, and M2 macrophage levels indicate aging-related molecules in the skin. Intestinal permeability was also suppressed. Thus, these changes together improved natural skin aging. CONCLUSIONS: This study revealed that B. coagulans administration improved the natural skin aging in mice. This enhancement might be induced by the interaction of alterations in intestinal flora, metabolites, or inflammatory substances.

Periprocedural and 30-day outcomes of robotic-assisted percutaneous coronary intervention used in the intravascular imaging guidance.

In recent years, there have been several reports on robotic-assisted percutaneous coronary intervention (R-PCI), but few studies have been conducted on R-PCI performed under intravascular imaging guidance. To elucidate the periprocedural and postoperative 30-day outcomes of intravascular imaging-guided R-PCI, we performed a retrospective observational study on all patients in 102 consecutive cases who underwent R-PCI under intravascular imaging guidance at a single center in Japan from June 12, 2019 to February 18, 2021. The primary end point was 30-day survival, and the secondary end point was the incidence of complications. Intravascular imaging-guided R-PCI was performed 110 times in total on 125 lesions. The medians of procedural time, fluoroscopy time, contrast volume, patient entrance skin dose, and radiation exposure to the main operator were 49 min, 16 min, 67 mL, 0.62 Gy, and 0 µSv, respectively. Furthermore, 60.0% of target lesion branches were American College of Cardiology Foundation/American Heart Association classification type B2 or type C. However, in all cases, lesion dilatation was successful, and the final Thrombolysis in Myocardial Infarction flow grade was 3. The combination of manual operation was required in 12.7% of all cases, but 30-day survival was confirmed in all cases. There were two problems at the puncture site. One small distal branch artery dissection occurred due to manual operation, but no cardiovascular events (myocardial infarction, stroke) occurred and no target lesion restenosis was observed within 30 days of R-PCI. Hence, R-PCI using intravascular imaging demonstrated highly satisfactory treatment outcomes, and no complication caused by robotic operation was observed.

Incidence and natural history of coronary evagination after implanted biodegradable polymer sirolimus-eluting stent.

Aims: The incidence and temporal change in coronary evagination (CE) after first-generation drug-eluting stent implantation is well established, whereas that after biodegradable polymer sirolimus-eluting stent (BP-SES) implantation has not yet been evaluated. The aim of this study is to assess the incidence and natural history of CE after BP-SES implantation. Methods and results: In this multicenter registry, stable coronary lesions treated by Ultimaster BP-SES were evaluated by serial optical frequency domain imaging (OFDI) (at 0-1-12 or 0-3-12 months) and the incidence of CE was assessed. Coronary evagination was defined as the presence of an outward bulge in luminal vessel contour between apposed struts according to the following criteria: (i) evagination depth ≥10% of nominal stent diameter and (ii) evagination length ≥3.0 mm. Optical frequency domain imaging was obtained in 98, 47, 49, and 87 lesions at 0, 1, 3, and 12 months, respectively. Coronary evagination was observed in 20 (42.6%) and 12 (24.5%) lesions at 1 and 3 months, respectively, and all but one CE had resolved at 12 months. At 12 months, the mean CE area was almost zero and the mean malapposed stent area was also decreased. Comparison of the serial OFDI images indicated that CEs originated mostly from acute stent malapposition or coronary dissection behind the implanted stent. Conclusions: In stable lesions, CE was occasionally observed with Ultimaster BP-SES at 1-3 months but mostly resolved within 12 months, without late-acquired stent malapposition. These findings suggest the safety and feasibility of biodegradable polymer coating on DES.

Prevalence, clinical characteristics, and impact of active cancer in patients with acute myocardial infarction: data from an all-comer registry.

BACKGROUND: Although a history of cancer is a poor prognostic factor in patients with acute myocardial infarction (AMI), the clinical importance of coexisting active cancer remains unclear. METHODS: In this single-center retrospective study, we reviewed an AMI registry and assessed the prevalence and predictors of active cancer, 1-year incidence of cardiac death or major bleeding events (defined as a Bleeding Academy Research Consortium type 3 or 5), and the impact of coexisting active cancer on clinical outcomes. Active cancer was defined as either an already-diagnosed or undiagnosed occult cancer. RESULTS: Between January 2012 and December 2017, 1140 AMI patients (median age, 69 years; male, 76.0%) were enrolled. Active and historical cancers were diagnosed in 63 patients (5.5%) and 50 patients (4.4%), respectively. The most common location was the urinary tract (n=21). In the Kaplan-Meier analysis, the active cancer group had a higher incidence of 1-year cardiac death (17.5% vs. 5.3%, p < 0.001) and major bleeding events (19.0% vs. 5.6%, p < 0.001) than the non-cancer group. In the multivariate Cox proportional hazards regression models, active cancer was an independent predictor of both cardiac death and major bleeding at 1 year. Specifically, gastrointestinal tract and advanced-stage cancers had the poorest outcomes. Compared to the non-cancer group, the 1-year major bleeding rate was higher for all cancer types and stages. In contrast, early-stage cancers had a weaker impact on the 1-year cardiac mortality compared to advanced-stage cancers. Similarly, cardiac death during 1-year also occurred less frequently in occult cancers than in already-known cancers. CONCLUSIONS: In patients with AMI, coexisting active cancer was rare, but it significantly impacted cardiac death and major bleeding events.

Novel KCNE3 mutation reduces repolarizing potassium current and associated with long QT syndrome.

Long QT syndrome (LQTS) is an inherited disease involving mutations in the genes encoding a number of cardiac ion channels and a membrane adaptor protein. Among the genes that are responsible for LQTS, KCNE1 and KCNE2 are members of the KCNE family of genes, and function as ancillary subunits of Kv channels. The third KCNE gene, KCNE3, is expressed in cardiac myocytes and interacts with KCNQ1 to change the channel properties. However, KCNE3 has never been linked to LQTS. To investigate the association between KCNE3 and LQTS, we conducted a genetic screening of KCNE3 mutations and single nucleotide polymorphisms (SNPs) in 485 Japanese LQTS probands using DHPLC-WAVE system and direct sequencing. Consequently, we identified two KCNE3 missense mutations, located in the N- and C-terminal domains. The functional effects of these mutations were examined by heterologous expression systems using CHO cells stably expressing KCNQ1. One mutation, p.R99lambdaH was identified in a 76-year-old woman who suffered torsades de pointes (TdP) after administration of disopyramide. Another mutation, p.T4A was identified in a 16-year-old boy and 67-year-old woman. Although the boy carried another KCNH2 mutation, he was asymptomatic. On the other hand, the woman suffered from hypokalemia-induced TdP. In a series of electrophysiological analyses, the KCNQ1(Q1)+KCNE3(E3)-R99lambdaH channel significantly reduced outward current compared to Q1+E3-WT, though the current density of the Q1+E3-T4A channel displayed no statistical significance. This is the first report of KCNE3 mutations associated with LQTS. Screening for variants in the KCNE3 gene is of clinical importance for LQTS patients.

A trafficking-deficient KCNQ1 mutation, T587M, causes a severe phenotype of long QT syndrome by interfering with intracellular hERG transport.

BACKGROUND: KCNQ1-T587M is a C-terminal mutation correlated with severe phenotypes of long QT syndrome (LQTS). However, functional analysis of KCNQ1 channels with the T587M mutation showed a mild genotype in the form of haploinsufficiency in a heterologous expression system. This study sought to explore the molecular mechanism underlying the phenotype-genotype dissociation of LQTS patients carrying the KCNQ1-T587M mutation. METHODS: cDNAs for wild-type (WT) and KCNQ1 mutations (R259C and T587M) were transiently transfected into HEK293 cells stably expressing hERG (hERG-HEK), and whole-cell patch-clamp technique was performed to examine the effect of KCNQ1 mutations on IKr-like currents. In addition, fluorescence resonance energy transfer (FRET) was conducted to demonstrate the molecular interaction between KCNQ1 and hERG when co-expressed in HEK293 cells. RESULTS: KCNQ1-T587M mutation produced a significant (p<0.01) decrease in IKr-like tail current densities without affecting the gating kinetics, while KCNQ1-R259C mutation had no significant effect on the IKr-like tail current densities. Consistent with this result, FRET experiments demonstrated that both KCNQ1-WT and -R259C interacted with hERG in the cytosol and on the plasma membrane; however, the interaction between KCNQ1-T587M and hERG was observed only in the cytosol, and hERG proteins were seldom transported to the cell membrane, suggesting that the KCNQ1-T587M mutation impaired the trafficking of hERG to the cell membrane. CONCLUSIONS: The disruption of hERG trafficking caused by the KCNQ1-T587M mutation is likely the reason why some patients exhibit severe LQTS phenotypes.

Age- and genotype-specific triggers for life-threatening arrhythmia in the genotyped long QT syndrome.

INTRODUCTION: Patients with long QT syndrome (LQTS) become symptomatic in adolescence, but some become at age of >or=20 years. Since it remains unknown whether clinical features of symptomatic LQTS patients differ depending on the age of onset, we aimed to examine whether triggers for cardiac events are different depending on the age in genotyped and symptomatic LQTS patients. METHODS AND RESULTS: We identified 145 symptomatic LQTS patients, divided them into three groups according to the age of first onset of symptoms (young <20, intermediate 20-39, and older >or=40 years), and analyzed triggers of cardiac events (ventricular tachycardia, syncope, or cardiac arrest). The triggers were divided into three categories: (1) adrenergically mediated triggers: exercise, emotional stress, loud noise, and arousal; (2) vagally mediated triggers: rest/sleep; and (3) secondary triggers: drugs, hypokalemia, and atrioventricular (AV) block. In the young group, 78% of the cardiac events were initiated by adrenergically mediated triggers and 22% were vagally mediated, but none by secondary triggers. In contrast, the adrenergically mediated triggers were significantly lower in the intermediate group. The percentage of secondary triggers was significantly larger in the older group than in the other two groups (0% in young vs 23% in intermediate vs 72% in older; P < 0.0001). Concerning the subdivision of secondary triggers on the basis of genotype, hypokalemia was only observed in LQT1, drugs mainly in LQT2, and AV block only in LQT2. CONCLUSION: Arrhythmic triggers in LQTS differ depending on the age of the patients, stressing the importance of age-related therapy for genotyped LQTS patients.

Genotype-phenotype correlations of KCNJ2 mutations in Japanese patients with Andersen-Tawil syndrome.

Andersen-Tawil syndrome (ATS) is a rare inherited disorder characterized by periodic paralysis, mild dysmorphic features, and QT or QU prolongation with ventricular arrhythmias in electrocardiograms (ECGs). Mutations of KCNJ2, encoding the human inward rectifying potassium channel Kir 2.1, have been identified in patients with ATS. We aimed to clarify the genotype-phenotype correlations in ATS patients. We screened 23 clinically diagnosed ATS patients from 13 unrelated Japanese families. Ten different forms of KCNJ2 mutations were identified in the 23 ATS patients included in this study. Their ECGs showed normal QTc intervals and abnormal U waves with QUc prolongation and a variety of ventricular arrhythmias. Especially, bidirectional ventricular tachycardia (VT) was observed in 13 of 23 patients (57%). Periodic paralysis was seen in 13 of 23 carriers (57%), dysmorphic features in 17 (74%), and seizures during infancy in 4 (17%). Functional assays for the two novel KCNJ2 mutations (c. 200G>A (p. R67Q) and c. 436G>A (p. G146S)) displayed no functional inward rectifying currents in a heterologous expression system and showed strong dominant negative effects when co-expressed with wild-type KCNJ2 channels (91% and 84% reduction at -50 mV respectively compared to wild-type alone). Immunocytochemistry and confocal imaging revealed normal trafficking for mutant channels. In our study, all of the clinically diagnosed ATS patients had KCNJ2 mutations and showed a high penetrance with regard to the typical cardiac phenotypes: predominant U wave and ventricular arrhythmias, typically bidirectional VT.

N- and C-terminal KCNE1 mutations cause distinct phenotypes of long QT syndrome.

BACKGROUND: Long QT syndromes (LQTS) are inherited diseases involving mutations to genes encoding a number of cardiac ion channels and a membrane adaptor protein. The MinK protein is a cardiac K-channel accessory subunit encoded by the KCNE1 gene, mutations of which are associated with the LQT5 form of LQTS. OBJECTIVE: The purpose of this study was to search for the KCNE1 mutations and clarify the function of those mutations. METHODS: We conducted a genetic screen of KCNE1 mutations in 151 Japanese LQTS patients using the denaturing high-performance liquid chromatography-WAVE system and direct sequencing. In two LQTS patients, we identified two KCNE1 missense mutations, located in the MinK N- and C-terminal domains. The functional effects of these mutations were examined by heterologous coexpression with KCNQ1 and KCNH2. RESULTS: One mutation, which was identified in a 67-year-old woman, A8V, was novel. Her electrocardiogram (ECG) revealed marked bradycardia and QT interval prolongation. Another mutation, R98W, was identified in a 19-year-old woman. She experienced syncope followed by palpitation in exercise. At rest, her ECG showed bradycardia with mild QT prolongation, which became more prominent during exercise. In electrophysiological analyses, R98W produced reduced I(Ks) currents with a positive shift in the half activation voltages. In addition, when the A8V mutation was coexpressed with KCNH2, this reduced current magnitude, which is suggestive of a modifier effect by the A8V KCNE1 mutation on I(Kr). CONCLUSION: KCNE1 mutations may be associated with mild LQTS phenotypes, and KCNE1 gene screening is of clinical importance for asymptomatic and mild LQTS patients.

Immunomodulating effect of vitamin D3 derivatives on type-1 cellular immunity.

1 alpha,25-dihydroxyvitamin D3 [Calcitriol or 1,25(OH)(2)D(3)] is an important active metabolite involved in multiple functions but its calcemic effect in vivo limits its therapeutic applications. On the other hand, 22-oxa-1 alpha,25-dihydroxyvitamin D(3) (22-oxacalcitriol or 22-Oxa-1 alpha,25-D(3)), a low calcemic analog of vitamin D3 (VitD3), has been widely used as a drug for the secondary hyperparathyroidism. Here, we investigated immunomodulating effect of these two VitD3 derivatives on the differentiation of type-1 immunoregulatory cells such as dendritic cells (DC1), cytotoxic T cells (Tc1) and helper T cells (Th1). BALB/c mouse bone marrow-derived DC (BMDC1) induced by culture with Th1 condition (GM-CSF, IL-3, IL-12 and IFN-gamma) expressed higher levels of MHC Class I and Class II molecules and co-stimulatory molecules compared with BMDC0 induced by neutral condition (GM-CSF+IL-3). In addition, BMDC1 showed stronger immunostimulating activity to induce alloantigen (H-2(d))-specific cytotoxic T lymphocytes (CTL) compared with BMDC0. However, if VitD3 derivatives were added into the culture for BMDC1 induction, the expression of functional molecules and type-1 IFNs were greatly inhibited. Moreover, VitD3 derivative-treated BMDC1 lost their immunostimulating activity to induce alloantigen-specific IFN-gamma-producing Tc1. In addition, it was demonstrated that the addition of VitD3 derivatives inhibited the differentiation of IFN-gamma-producing Th1 cells from ovalbumin (OVA)-specific naive Th cells, while it rather augmented the differentiation of IL-4- or IL-10-producing Th2 cells. There was no significant difference in immunomodulating activity between 1,25(OH)(2)D(3) and 22-Oxa-1 alpha,25-D(3). Thus, VitD3 derivatives are demonstrated to inhibit the functional differentiation of DC1, Tc1 and Th1 cells, which play a critical role in type-1 cellular immune responses.

Novel KCNJ2 mutation in familial periodic paralysis with ventricular dysrhythmia.

BACKGROUND: Mutations in the KCNJ2 gene, which codes cardiac and skeletal inward rectifying K+ channels (Kir2.1), produce Andersen's syndrome, which is characterized by periodic paralysis, cardiac arrhythmia, and dysmorphic features. METHODS AND RESULTS: In 3 Japanese family members with periodic paralysis, ventricular arrhythmias, and marked QT prolongation, polymerase chain reaction/single-strand conformation polymorphism/DNA sequencing identified a novel, heterozygous, missense mutation in KCNJ2, Thr192Ala (T192A), which was located in the putative cytoplasmic chain after the second transmembrane region M2. Using the Xenopus oocyte expression system, we found that the T192A mutant was nonfunctional in the homomeric condition. Coinjection with the wild-type gene reduced the current amplitude, showing a weak dominant-negative effect. CONCLUSIONS: T192, which is located in the phosphatidylinositol-4,5-bisphosphate binding site and also the region necessary for Kir2.1 multimerization, is a highly conserved amino acid residue among inward-rectifier channels. We suggest that the T192A mutation resulted in the observed electrical phenotype.