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The ability to tune the electronic properties of molecular arrays is an important step in the development of molecule-scale electronic devices. However, control over internal device charge distributions by tuning interactions between molecules has proved challenging. Here, we show that gate-tunable charge patterning can occur in one-dimensional molecular arrays on graphene field-effect transistors. One-dimensional molecular arrays are fabricated using an edge-templated self-assembly process that allows organic molecules (F4TCNQ) to be precisely positioned on graphene devices. The charge configurations of the molecular arrays can be reversibly switched between different collective charge states by tuning the graphene Fermi level via a back-gate electrode. Charge pinning at the ends of the molecular arrays allows the charge state of the entire array to be controlled by adding or removing an edge molecule and changing the total number of molecules in an array between odd and even integers. Charge patterns altered in this way propagate down the array in a cascade effect, allowing the array to function as a charge-based molecular shift register. An extended multi-site Anderson impurity model is used to quantitatively explain this behaviour. One-dimensional molecular arrays on graphene field-effect transistors can be reversibly switched between different periodic charge states by tuning the graphene Fermi level via a back-gate electrode and by manipulating individual molecules, allowing them to function as a nanoscale shift register.

Although impingement/effusion cooling systems have been extensively studied over the past several decades, studies on flow and heat transfer characteristics over a wide range of geometrical and flow parameters are still lacking. Moreover, most studies have been related to gas-turbine blade cooling, and only a few studies have focused on gas-turbine casing cooling. In addition, studies that attempted to develop a Nusselt number correlation for jet array impingement with effusion holes––where these holes are installed in the impingement plate––are scarce. This study primarily aimed to explore the heat transfer characteristics of jet array impingement with effusion holes and to provide basic data for the design of a gas-turbine casing cooling system. Perforated circular holes in two parallel plates were arranged in a staggered configuration. The air injected through the jet holes impacts the impingement plate, and the spent air from the impinging jets is then discharged through the effusion holes in the impingement plate. A three-dimensional numerical unit cell model was constructed to investigate the effect of the hole pitch, distance between the jet plate and the impingement plate, Reynolds number based on the hole diameter, and hole diameter on the impingement heat transfer. The numerical model was validated by comparing its numerical predictions for a wide range of geometric parameters using previous experimental data. The local and average Nusselt numbers on the impingement plane were obtained for 74 simulation cases, and the results show that the jet potential core has a significant influence on the flow structure and heat transfer in a confined jet impingement. The accuracy of previous Nusselt number correlations for a jet array impingement was assessed, and we proposed a new correlation for predicting the average Nusselt number for a jet array impingement with effusion holes.

The ability to tune the band-edge energies of bottom-up graphene nanoribbons (GNRs) via edge dopants creates new opportunities for designing tailor-made GNR heterojunctions and related nanoscale electronic devices. Here we report the local electronic characterization of type II GNR heterojunctions composed of two different nitrogen edge-doping configurations (carbazole and phenanthridine) that separately exhibit electron-donating and electron-withdrawing behavior. Atomically resolved structural characterization of phenanthridine/carbazole GNR heterojunctions was performed using bond-resolved scanning tunneling microscopy and noncontact atomic force microscopy. Scanning tunneling spectroscopy and first-principles calculations reveal that carbazole and phenanthridine dopant configurations induce opposite upward and downward orbital energy shifts owing to their different electron affinities. The magnitude of the energy offsets observed in carbazole/phenanthridine heterojunctions is dependent on the length of the GNR segments comprising each heterojunction with longer segments leading to larger heterojunction energy offsets. Using a new on-site energy analysis based on Wannier functions, we find that the origin of this behavior is a charge transfer process that reshapes the electrostatic potential profile over a long distance within the GNR heterojunction.

Bottom-up fabrication techniques enable atomically precise integration of dopant atoms into the structure of graphene nanoribbons (GNRs). Such dopants exhibit perfect alignment within GNRs and behave differently from bulk semiconductor dopants. The effect of dopant concentration on the electronic structure of GNRs, however, remains unclear despite its importance in future electronics applications. Here we use scanning tunneling microscopy and first-principles calculations to investigate the electronic structure of bottom-up synthesized N = 7 armchair GNRs featuring varying concentrations of boron dopants. First-principles calculations of freestanding GNRs predict that the inclusion of boron atoms into a GNR backbone should induce two sharp dopant states whose energy splitting varies with dopant concentration. Scanning tunneling spectroscopy experiments, however, reveal two broad dopant states with an energy splitting greater than expected. This anomalous behavior results from an unusual hybridization between the dopant states and the Au(111) surface, with the dopant-surface interaction strength dictated by the dopant orbital symmetry.

To evaluate the role of herbal medicine in drug-induced parkinsonism (DIP) and identify an optimal treatment approach.Retrospective review of DIP cases treated with herbal medicine.The Parkinson's clinic at Kyung Hee Traditional Korean Medicine Hospital, Korea.Twenty-one patients whose clinical outcome and offending drug could be identified.Clinical features, treatments, and outcomes and summarized the clinical course and treatment in each case.Twelve patients had levosulpiride-induced parkinsonism and 9 had parkinsonism induced by another drug. The offending drugs were discontinued in all patients, and all patients received herbal medications during treatment. Nine of 12 patients with parkinsonism from levosulpiride and 4 of 9 patients with parkinsonism from other drugs had complete reversal of symptoms. The most frequently used herbal formula was Ukgansan (Yigansan). DIP in the levosulpiride group tended to improve faster with herbal medicine, and the percentage of improvement was higher.Optimal herbal medicine treatments chosen after a careful history and evaluation for risk factors may be helpful in reversing DIP.

Bottom-up synthesized graphene nanoribbons and graphene nanoribbon heterostructures have promising electronic properties for high-performance field-effect transistors and ultra-low power devices such as tunneling field-effect transistors. However, the short length and wide band gap of these graphene nanoribbons have prevented the fabrication of devices with the desired performance and switching behavior. Here, by fabricating short channel (L ch ~ 20 nm) devices with a thin, high-κ gate dielectric and a 9-atom wide (0.95 nm) armchair graphene nanoribbon as the channel material, we demonstrate field-effect transistors with high on-current (I on > 1 μA at V d = −1 V) and high I on /I off ~ 105 at room temperature. We find that the performance of these devices is limited by tunneling through the Schottky barrier at the contacts and we observe an increase in the transparency of the barrier by increasing the gate field near the contacts. Our results thus demonstrate successful fabrication of high-performance short-channel field-effect transistors with bottom-up synthesized armchair graphene nanoribbons., Graphene nanoribbons show promise for high-performance field-effect transistors, however they often suffer from short lengths and wide band gaps. Here, the authors use a bottom-up synthesis approach to fabricate 9- and 13-atom wide ribbons, enabling short-channel transistors with 105 on-off current ratio.

Chunghyul-Dan (CHD) is the first choice agent for the prevention and treatment of stroke at the Kyung Hee Medical Hospital. To date, CHD has been reported to have beneficial effects on brain disease in animals and humans, along with antioxidative and anti-inflammatory effects. The aim of this study was to evaluate the pharmacological effects of CHD on a traumatic brain injury (TBI) mouse model to explore the possibility of CHD use in patients with TBI. The TBI mouse model was induced using the controlled cortical impact method. CHD was orally administered twice a day for 5 d after TBI induction; mice were assessed for brain damage, brain edema, blood-brain barrier (BBB) damage, motor deficits, and cognitive impairment. Treatment with CHD reduced brain damage seen on histological examination and improved motor and cognitive functions. However, CHD did not reduce brain edema and BBB damage. In conclusion, CHD could be a candidate agent in the treatment of patients with TBI. Further studies are needed to assess the exact mechanisms of the effects during the acute-subacute phase and pharmacological activity during the chronic-convalescent phase of TBI.

To perform effective integration test of avionics equipments, the importance of a setup for integration test environment has been increasing in recently developed aircraft. Especially, the development of integration test equipment is necessary for minimizing the development period and reliability of integration test. This paper treats the model development for optimal working of integration test after analyzing the characteristics of each MEP equipments for Surion(KUH). Models, whose main role is troubleshooting of equipment and simulation for missing equipments, consists of dynamic, behavior, and ICD models depending on the dynamic characteristics. Software test for both unit level and system level are performed to verify the model reliability. By conducting integration test using SIL, it is confirmed that the developed models are suitable for integration function test of the MEP system.

Photodynamic therapy using topical 5-aminolevulinic acid (ALA) has been successful in treating acne vulgaris, but sun avoidance for at least 48 hours after treatment is necessary due to the risk of post-treatment photosensitivity. Recently, a lower concentration of liposome-encapsulated 5-ALA was introduced to minimize this risk.To evaluate the efficacy and safety of liposome-encapsulated 0.5% 5-ALA in the photodynamic therapy of inflammatory acne and its effects on sebum secretion in Asian skin.Thirteen Korean subjects with inflammatory acne were administered 0.5% ALA spray before photoradiation treatment. Photoradiation was performed at 3.5-6.0 J/cm(2) three times during each of two visits, performed 2 weeks apart. Improvement of acne was evaluated subjectively and objectively based on the Korean Acne Grading System. Sebum secretion was measured quantitatively at each visit.The mean reduction in acne grade at the end of the treatment was 43.2%. Of the patients, 69.2% reported improvements in subjective skin oiliness, but fewer showed objective reductions in sebum secretion as determined by the Sebumeter® SM10. No serious adverse events were observed.Photodynamic therapy using liposome-encapsulated 0.5% 5-ALA improved inflammatory acne with minimal side effects in Asians.

With the development of optimal surface cleaning techniques by cluster ion beam sputtering, certain applications of SIMS for analyzing cells and tissues have been actively investigated. For this report, we collaborated with bio-medical scientists to study bio-SIMS analyses of skin and cancer tissues for biomedical diagnostics. We pay close attention to the setting up of a routine procedure for preparing tissue specimens and treating the surface before obtaining the bio-SIMS data. Bio-SIMS was used to study two biosystems, skin tissues for understanding the effects of photoaging and colon cancer tissues for insight into the development of new cancer diagnostics for cancer. Time-of-flight SIMS imaging measurements were taken after surface cleaning with cluster ion bombardment by Bin or C60 under varying conditions. The imaging capability of bio-SIMS with a spatial resolution of a few microns combined with principal component analysis reveal biologically meaningful information, but the lack of high molecular weight peaks even with cluster ion bombardment was a problem. This, among other problems, shows that discourse with biologists and medical doctors are critical to glean any meaningful information from SIMS mass spectrometric and imaging data. For SIMS to be accepted as a routine, daily analysis tool in biomedical laboratories, various practical sample handling methodology such as surface matrix treatment, including nano-metal particles and metal coating, in addition to cluster sputtering, should be studied.

Pemphigus, a rare, chronic blistering disease of the skin and mucous membranes with severe morbidity and occasional mortality, is the most common autoimmune bullous disease in Korea. The purpose of this study was to evaluate the clinical features and propose a treatment strategy for patients with pemphigus. A retrospective analysis was conducted of 51 pemphigus patients seen between 1993 and 2001. Pemphigus vulgaris (PV) was the most common type with 32 cases, followed by 19 cases of pemphigus foliaceus (PF). The male to female ratio was 1:1.3, with females predominating, particularly among PV patients (PV, 1:1.5; PF, 1:1.1). The average ages at onset of PV and PF were 44.3 and 51.0 years old, respectively. Mucosal involvement was noted in 27 cases (84.4%) of PV but in only 3 cases (15.8%) of PF. Most patients initially received relatively low to intermediate doses (0.3-1.0 mg/kg/day) of prednisolone, and 23 (71.9%) PV patients and 10 (52.6%) PF patients also received immunosuppressive agents. Oral prednisolone and azathioprine (100 mg/day) formed the mainstay of treatment for our patients (47.1%). At the time of writing, 25.5% (13/51) of patients are in complete remission, and 72.5% (37/51) are undergoing maintenance therapy. One patient died due to sepsis during the treatment. For the treatment of pemphigus, a course of the lowest possible corticosteroid dosage in combination with immunosuppressive agents appears to be effective and less toxic than a high corticosteroid dosage.

Summary Background Sensitive skin represents hyperactive sensory symptoms showing exaggerated reactions in response to internal stimulants or external irritants. Although sensitive skin is a very common condition affecting an estimated 50% of the population, its pathophysiology remains largely elusive, particularly with regard to its metabolic aspects. Objective The objective of our study was to investigate the pathogenesis of sensitive skin. Methods We recruited healthy participants with ‘sensitive' or ‘non-sensitive' skin based on standardized questionnaires and 10% lactic acid stinging test, and obtained skin samples for microarray analysis and subsequent experiments. Results Microarray transcriptome profiling revealed that genes involved in muscle contraction, carbohydrate and lipid metabolism, and ion transport and balance were significantly decreased in sensitive skin. These altered genes could account for the abnormal muscle contraction, decreased ATP amount in sensitive skin. In addition, pain-related transcripts such as TRPV1, ASIC3 and CGRP were significantly up-regulated in sensitive skin, compared with non-sensitive skin. Conclusions Our findings suggest that sensitive skin is closely associated with the dysfunction of muscle contraction and metabolic homeostasis.

Right and left filling pressures are important parameters in the automatic control of a total artificial heart (TAH) within normal physiologic ranges. Our TAH is composed of a moving actuator, right and left ventricles, and an interventricular space (IVS) enclosed by a semirigid housing. During operation of the TAH, the IVS volume is changed dynamically by the difference between the ejection volume of one ventricle and the inflow volume of the other. We measured the interventricular pressure (IVP) waveform by using a pressure sensor and analyzed the relationship between the IVP and the preload condition. From in vitro and in vivo experiments, we found that the measured filling pressures were linearly related to the negative peak value of the IVP. Additionally, we found that we could use the time interval from actuator start to the positive peak value of the IVP (outflow valve opening) as a useful parameter to estimate the blood filling volume of the diastole ventricle.

A new automatic cardiac output control algorithm for an implantable electromechanical total artificial heart (TAH) was developed based on the analysis of motor current waveform without using any transducer. The basic control requirements of an artificial heart can be described in terms of three features: preload sensitivity, afterload insensivity, and balanced ventricular output. In previous studies, transducers were used to acquire information on the hemodynamic states for automatic cardiac output control. However, such a control system has reliability problems with the sensors. We proposed a novel sensorless automatic cardiac output control algorithm (ACOCA) providing adequate cardiac output to the time-varying physiological demand without causing right atrial collapse, which is one of the critical problems in an active filling device. In vitro tests were performed on a mock circulatory system to assess the performance of the developed algorithm and the results show that the new algorithm satisfied the basic control requirements of the cardiac output response.

From an engineering point of view, the suitable revolution number for high efficiency operation of an axial flow pump is known. A multistage axial flow pump is a useful tool for reducing revolution number with a high efficiency axial flow pump. A two stage (25) axial flow pump designed at a 5 L/min flow rate and a 100 mmHg pressure head was evaluated in three kinds of in vitro hemolysis tests. Each stage design point of the 2s pump was tested at a 5 L/min flow rate and a 50 mmHg pressure head. Specific speed and revolution number of the 2S pump were 1400 rpm, m3/min, m, and 15500 rpm, respectively. In the first test the 2S pump was compared with two single stage axial flow pumps (1S-A and 1S-B100) designed by the same method. The specific speed of the 1A was the same as that of the 2S pump, which was driven at 26000 rpm. The impeller of the 1S-B100 was the same as that of the 2S pump, which was driven at a 22000 rpm RN and a 1100 specific speed. The 2S pump was separated into two single stage axial flow pumps and the effect of series operation on hemolysis was evaluated in the second test. In the third test the 2S pump was compared with the 1S-B100 by using diluted goat blood samples with three different hematocrit values. The results showed that the hemolysis index of the 2S pump, regarded as a total hemolysis index of both stage axial flow pumps, was less than those of the single stage axial flow pumps at all hematocrit values.

In this study, cells from the stromal vascular fraction of human subcutaneous tissues were induced to differentiate toward adipose cells in vitro for 2 weeks. During adipogenic differentiation, we followed the chronological changes in their morphology with Coherent anti-Stokes Raman scattering (CARS) microscopy and checked the PPAR-γ and UCP-1 expression with RT-PCR. On day 4 after inducing adipogenic differentiation, CARS imaging showed multiple small lipid droplets (LD) distributed peripherally along the cellular membrane. PPAR-γ began to express at this time and increased until day 14 at a steady rate. On day 7, the cells appeared as brown adipocytes with numerous small LD throughout the cytoplasm, and the mRNA level of UCP-1 rose abruptly by 6- to 7-fold. After an additional 7 days, CARS imaging showed the development of a large LD, which is characteristic of white adipocytes, and the mRNA level of UCP-1 slumped significantly. These results demonstrate the possibility that ADSC pass through a brown adipocyte-like stage while differentiating into white adipocytes.

The layers of keratinocytes form an acid mantle on the surface of the skin. Herein, we investigated the effects of acidic pH on the membrane current and [Ca(2+)](c) of human primary keratinocytes from foreskins and human keratinocyte cell line (HaCaT). Acidic extracellular pH (pH(e)/= 5.5) activated outwardly rectifying Cl(-) current (I(Cl,pH)) with slow kinetics of voltage-dependent activation. I(Cl,pH) was potently inhibited by an anion channel blocker 4,4'-diisothiocyanostilbene-2,2'-disulphonic acid (DIDS, 73.5% inhibition at 1 microM). I(Cl,pH) became more sensitive to pH(e) by raising temperature from 24 to 37. HaCaT cells also expressed Ca(2+)-activated Cl(-) current (I(Cl,Ca)), and the amplitude of I(Cl,Ca) was increased by relatively weak acidic pH(e) (7.0 and 6.8). Interestingly, the acidic pH(e) (5.0) also induced a sharp increase in the intracellular [Ca(2+)] (Delta[Ca(2+)](acid)) of HaCaT cells. The Delta[Ca(2+)](acid) was independent of extracellular Ca(2+), and was abolished by the pretreatment with PLC inhibitor, U73122. In primary human keratinocytes, 5 out of 28 tested cells showed Delta[Ca(2+)](acid). In summary, we found I(Cl,pH) and Delta[Ca(2+)](acid) in human keratinocytes, and these ionic signals might have implication in pathophysiological responses and differentiation of epidermal keratinocytes.

A 5-year-old girl with a family history of LEOPARD syndrome had multiple lentigines on the face and trunk, hypertelorism, and growth retardation. In addition, she had congenital corneal tumors on both eyes. Histologically the tumors were choristoma. The neuroectodermal origin hypothesis of LEOPARD syndrome could explain the presence of a congenital corneal tumor in this patient. We suggest that corneal tumor may represent an unrecognized associated finding in this syndrome.

We describe two Korean adult patients who had necrotizing papulovesicles mainly on their faces. Skin biopsy specimens showed perivascular and periadnexal infiltrate of atypical lymphoid cells with vasculitis in the dermis and subcutaneous tissue. In situ hybridization demonstrated a latent infection of Epstein–Barr virus in the majoriy of lymphoid cells in the dermis. These patients were diagnosed as having T-cell lymphoma. Interestingly, large granular lymphocytosis was found in the peripheral blood of Case 2.

We have studied the clinicopathological features of 19 Korean cases of peripheral T-cell and natural killer (NK) cell lymphomas, not including mycosis fungoides. Primary cutaneous involvement was demonstrated in eight of these 19 cases, and we recognized four clinicopathologic subtypes among these eight patients: nasal type NK/T cell lymphoma, three cases; primary cutaneous CD30 positive anaplastic large cell lymphoma, two cases; subcutaneous panniculitis-like T-cell lymphoma, one case; lymphoma with hydroa vacciniforme-like cutaneous lesions, two cases. We did not, however, encounter any cases of HTLV-associated adult T-cell lymphoma/leukemia, which is common in Taiwan and Japan. EBV-associated lymphoma is the most prominent type of peripheral T-cell and NK cell neoplasm involving the skin in Korea.

The electromechanical total artificial heart (TAH) developed at Seoul National University Hospital was verified as acceptable for human implantation through several successful animal experiments. In the last two years (1994–1996), the TAH was redesigned to be small (600–650 ml, total volume) and lightweight (approimately 950 g), and also improved to overcome three practical problems encountered in the animal experiments. First, we implemented modifications to the blood-pump housing to resolve the anatomical problem made apparent through the construction of a three-dimensional model of the TAH, the human thoracic cavity, and the large vessels, from magnetic resonance images and Angiogram-Computer tomography. Second, the intraventricular surface of the blood sacs was modified with fibrinolytic and anti-infective surface treatments. Third, the mechanism of regulation of cardiac output (CO) was improved by analyzing the measured pressure in the interventricular volume space (IVP). It proved beneficial to achieve the regulation of CO in response to the physiological demand, and to prevent atrial collapse due to the suction. The IVP, which accurately reflected the hemodynamic parameters, was used to predict the preload condition. These three improvements will assist in the application of the newly developed implantable electromechanical artificial heart for long-term implantation.

The right and left atrial pressures are important parameters in the automatic control of a total artificial heart (TAH) within normal physiological ranges. Our TAH is composed of a moving actuator, right and left ventricles, and the interventricular space (IVS) enclosed by a semirigid housing. During operation of the TAH, the IVS volume is changed dynamically by the difference between the ejection volume of one ventricle and the inflow volume of the other. Therefore, the change in pressure of the IVS is related to both right and left atrial pressures. We measured the interventricular pressure (IVP) waveform using a pressure sensor and attempted to estimate indirectly the changes in atrial pressures. This method has the advantage that the sensor does not contact the blood directly. Furthermore, the IVP waveform has a zero baseline in each pump cycle, thus the pressure measurements are free from transducer drift problems because the peak pressure can be measured from these baseline values. From in vitro experiments, we found that the IVP waveform contained several useful parameters such as negative peak IVP value, dP/dton the initial break, and the area enclosed by the profile for each stroke, each of which are associated with the left and right atrial pressures and the filling conditions of the ventricles. The measured atrial pressures were linearly related to the negative peak value of the interventricular pressure.

The development of a control method for the totally implantable artificial heart (TAH) to regulate cardiac output according to the change in physiological demand was the goal of this study. The conventional proportional-integral-derivative (PID) controller was used for the automatic regulation of the cardiac output. Furthermore, using a fuzzy gain-tuning algorithm, the PID controller parameters were adaptively tuned to the optimal operating point of the process, which varied with hemodynamic disturbances. To determine the physiological demand, the interventricular pressure (IVP) inside the TAH was used to estimate inflow conditions. The negative peak value of the IVP at each diastolic period has a linear relation to the corresponding atrial pressure. Based on the relationship of atrial pressure to the IVP, the automatic control algorithm proposed regulates the optimal pump rate in terms of sufficient cardiac output delivery under a given venous return. To maintain a well-balanced left and right pump output from the volumetrically coupled, circular moving actuator type TAH, the automatic control also adjusts an asymmetric amount of the moving actuator stroke angle, which provides a different net output of the ventricles. The in vitro performance of the newly developed automatic control method was assessed using a mock circulatory system. Over a physiological range of preload, -3–15 mmHg of right atrial pressure (RAP) and 80–120 mmHg of aortic pressure (AoP), the cardiac output varied from 4.2 to 6.31/min with the left atrial pressure (LAP) maintained below 15 mmHg.

An electrohydraulically driven left ventricular assist device (LVAD) has been developed in our laboratory. Over years of in vitro and in vivo testing, a “suction” problem has been pointed out as one of the major problems related to the device mechanism. The suction problem involves collapse of the left atrium, which can be caused by excessive negative pressure generated by the active blood-filling mechanism, and can lead to damage to the atrium or an air-embolism. We have developed methods for properly controlling the assistance output, depending upon the inlet pressure conditions. Algorithms have been developed for setting an absolute limit to negative pressure and for the regulation of the diastolic velocity of the device. The regulating system is based on the estimation of left atrial pressure (LAP), using the internal pressure of the polymer bellows and the motor current as raw information indicating the status of the left atrium. The estimation is based upon direct analysis of the signal wave form, coupled with the use of fuzzy logic in determining significant parameters such as the systolic peak, diastolic peak, and diastolic integral. Results of experiments using a mock-circulation system have shown that the new control system performs satisfactorily in detecting suction. An animal experiment was conducted to verify the feasibility of the methods. In a 17-day experiment using an adult sheep with a left ventricular assist device, there was no sign of damage or suction-related problems when we used the new method for controlling the diastolic velocity depending upon the bellows water pressure. In this paper, the methods are described and the results are documented.

The layers of keratinocytes form an acid mantle on the surface of the skin. Herein, we investigated the effects of acidic pH on the membrane current and [Ca2+]c of human primary keratinocytes from foreskins and human keratinocyte cell line (HaCaT). Acidic extracellular pH (pHe≤ 5.5) activated outwardly rectifying Cl- current (ICl,pH) with slow kinetics of voltage-dependent activation. ICl,pH was potently inhibited by an anion channel blocker 4,4'-diisothiocyanostilbene-2,2'-disulphonic acid (DIDS, 73.5% inhibition at 1 µM). ICl,pH became more sensitive to pHe by raising temperature from 24℃ to 37℃. HaCaT cells also expressed Ca2+-activated Cl- current (ICl,Ca), and the amplitude of ICl,Ca was increased by relatively weak acidic pHe (7.0 and 6.8). Interestingly, the acidic pHe (5.0) also induced a sharp increase in the intracellular [Ca2+] (Δ[Ca2+]acid) of HaCaT cells. The Δ[Ca2+]acid was independent of extracellular Ca2+, and was abolished by the pretreatment with PLC inhibitor, {"type":"entrez-nucleotide","attrs":{"text":"U73122","term_id":"4098075","term_text":"U73122"}}U73122. In primary human keratinocytes, 5 out of 28 tested cells showed Δ[Ca2+]acid. In summary, we found ICl,pH and Δ[Ca2+]acid in human keratinocytes, and these ionic signals might have implication in pathophysiological responses and differentiation of epidermal keratinocytes.