Immunogenicity and safety of SARS-CoV-2 recombinant protein nanoparticle vaccine GBP510 adjuvanted with AS03: interim results of a randomised, active-controlled, observer-blinded, phase 3 trial.

Background: GBP510 vaccine contains self-assembling, recombinant nanoparticles displaying SARS-CoV-2 spike receptor-binding domains. We report interim phase 3 immunogenicity results for GBP510 adjuvanted with AS03 (GBP510/AS03) compared with ChAdOx1-S (Vaxzevria, AstraZeneca) in healthy adults aged ≥18 years, up to 6 months after the second dose. Methods: This was a randomised, active-controlled, observer-blinded, parallel group, phase 3 study, conducted at 38 sites across six countries (South Korea, Philippines, Thailand, Vietnam, Ukraine and New Zealand). Cohort 1 (no history of SARS-CoV-2 infection/COVID-19 vaccination) was randomised 2:1 to receive two doses of GBP510/AS03 or ChAdOx1-S (immunogenicity and safety), while Cohort 2 (regardless of baseline serostatus) was randomised 5:1 (safety). Primary objectives were to demonstrate superiority in geometric mean titre (GMT) and non-inferiority in seroconversion rate (SCR; ≥4-fold rise from baseline) of GBP510/AS03 vs. ChAdOx1-S for neutralising antibodies against the ancestral strain by live-virus neutralisation assay. Secondary objectives included assessment of safety and reactogenicity (long-term 6 months cut-off date: 09 August 2022). This study was registered on ClinicalTrials.gov (NCT05007951). Findings: Between 30 August 2021 and 11 January 2022, a total of 4913 participants were screened and 4036 participants (1956 in Cohort 1 and 2080 in Cohort 2) who met eligibility criteria were enrolled and randomised to receive 2 doses of GBP510/AS03 (n = 3039) or ChAdOx1-S (n = 997). Most participants were Southeast Asian (81.5%) and aged 18-64 years (94.7%). The primary objectives assessed in per-protocol set included 877 participants in GBP510/AS03 and 441 in ChAdOx1-S group: at 2 weeks after the second vaccination, the GMT ratio (GBP510/AS03/ChAdOx1-S) in per-protocol set was 2.93 (95% CI 2.63-3.27), demonstrating superiority (95% CI lower limit >1) of GBP510/AS03; the between-group SCR difference of 10.8% (95% CI 7.68-14.32) also satisfied the non-inferiority criterion (95% CI lower limit > -5%). Neutralizing antibody titres sustained higher for the GBP510/AS03 group compared to the ChAdOx1-S group through 6 months after the second vaccination. In Safety analysis (Cohort 1 & 2), the proportion of participants with adverse events (AEs) after any vaccination was higher with GBP510/AS03 vs. ChAdOx1-S for solicited local AEs (56.7% vs. 49.2%), but was similar for solicited systemic AEs (51.2% vs. 53.5%) and unsolicited AEs (13.3% vs. 14.6%) up to 28 days after the second vaccination. No safety concerns were identified during follow-up for 6 months after the second vaccination. Interpretation: Our interim findings suggested that GBP510/AS03 met the superiority criterion for neutralising antibodies and non-inferiority criterion for SCR compared with ChAdOx1-S, and showed a clinically acceptable safety profile. Funding: This work was supported, in whole or in part, by funding from CEPI and the Bill & Melinda Gates Foundation Investments INV-010680 and INV-006462. The Bill & Melinda Gates Foundation supported this project for the generation of IND-enabling data and CEPI supported this clinical study.

A Cross-Sectional Study on the Psychological Changes of Medical Personnel in Hospitals Who Experienced Special COVID-19 Situations.

The COVID-19 pandemic contributed to an increase in mental health issues; Psychological changes occur in health professionals who are more susceptible to infection. The purpose of this study was to investigate health professionals' levels of anxiety, rage, and depression in COVID-related special circumstances. A general hospital in Korea experienced a widespread COVID-19 outbreak. There was a total of 149 involved frontline and non-frontline health professionals surveyed. The State-Trait Anger Expression Inventory, General Anxiety Disorder-7, and Korean Screening Tool for Depressive Disorders were utilized in the evaluation of their rage, anxiety, and depression. Anxiety and depression were found to be significantly higher among health professionals by occupation than among non-health professionals. Frontline workers were more depressed than non-frontline workers, according to type of work. These psychological changes can cause PTSD, so it is necessary to check and care for the mental health of health care workers working in medical institutions in the event of mass infections. These issues have been confirmed through studies related to the occurrence of mass infections such as SARS and MERS that the occurrence of mass infections can cause PTSD. The findings proved that the COVID-19 pandemic had a psychological impact on healthcare workers. During the COVID-19 pandemic, it is critical to raise awareness of post-traumatic stress disorder among healthcare professionals.

The efficacy and safety of tadalafil in the management of erectile dysfunction with diabetes and blood circulation issues.

BACKGROUND: Erectile dysfunction (ED) is a common diabetes-related complication. MATERIALS AND METHODS: This study examined the effect of daily low-dose tadalafil (5 mg) on patients' quality of life (including that of sex life) and blood circulation. Erectile dysfunction questionnaires were administered to 20 patients with type 2 diabetes (T2DM) and ED. The safety and efficacy of tadalafil were evaluated using laboratory tests, and the effect on blood circulation was measured through nail fold capillaroscopy. RESULTS: Daily tadalafil use by patients with T2DM and ED showed a statistically significant increase in the erectile reliability score from of 1.15 to 3.20 (p < .00012). Capillary blood circulation improvement tests showed a statistically significant increase in apical limb width from 13.1 to 14.64 µm (p = .04829) and flow from 9035 to 11946 µm3/s (p = .04405). Although not significant, increased capillary width and speed (rate of blood flow) confirmed improved blood circulation. There were no significant changes in the cardiac indicators (troponin, prostate-specific antigen, or electrocardiogram tests) before and after tadalafil administration, supporting the safety of its low-dose daily administration. CONCLUSIONS: A small dose of daily tadalafil was shown to safely improve erectile dysfunction and peripheral blood flow in patients with T2DM, in which peripheral arterial diseases should not be considered separately but rather as complex entities.

Results from a large post-marketing safety surveillance study in the Republic of Korea with a quadrivalent meningococcal CRM-conjugate vaccine in individuals aged 2 months-55 years.

The quadrivalent meningococcal conjugate vaccine MenACWY-CRM is approved in the Republic of Korea for use in individuals from 2 months of age. This single-arm, open-label, observational, multicenter, post-marketing study (NCT01766206) assessed the safety of MenACWY-CRM vaccine administered according to local clinical practice. A total of 3939 individuals aged 2 months-55 years provided safety data post-vaccination; the analysis was conducted on the per-protocol set (3920 participants). Solicited and unsolicited adverse events (AEs) were collected over 7 days post-vaccination and medically-attended AEs (MAAEs) and serious AEs (SAEs) over 29 days post-vaccination. Among recorded solicited AEs, injection site AEs were reported by 21.38% of participants, with tenderness/pain being most frequent across age groups; systemic AEs were reported in 13.95% of participants, with irritability (in ˂6-year-olds), headache and myalgia (in ≥6 year-olds) being the most frequently reported. Most solicited AEs were mild or moderate in nature. The percentage of participants reporting unsolicited AEs varied in the study population, i.e. 12.56% in participants aged 2-23 months and 3.18% in those ≥2 years of age. Overall, less than 22% of unsolicited AEs were considered as related to vaccination. MAAEs (10.89% of participants) were mostly mild; 2.82% were considered as related to vaccination. Three (0.46%) and 5 (0.15%) SAEs (none vaccination-related) occurred in participants aged 2-23 months and 2-55 years, respectively. No deaths were reported. The safety profile for MenACWY-CRM in this post-marketing surveillance was consistent with observations from studies conducted during the vaccine's clinical development, with no new safety concerns.

The factors associated with Vitamin D deficiency in community dwelling elderly in Korea.

BACKGROUND/OBJECTIVES: Recent studies showed vitamin D deficiency is linked to chronic diseases in addition to skeletal metabolism which could threaten the elderly. We analyzed health conditions and socio-demographic factors associated with vitamin D deficiency in community dwelling people aged 65 years and older. SUBJECTS/METHOD: Data from the Korea National Health and Nutrition Examination Survey (KNHANES) 2010 to 2012 were obtained. A total of 2,687 subjects aged 65 years and older were participated. The cutoff value of the Vitamin D deficiency was considered as serum 25-hydroxyvitamin D [25(OH)D] ≤ 20 ng/mL (50 nmol/L). RESULTS: The overall prevalence rate of vitamin D deficiency in the elderly was 62.1%. The factors such as female, obesity, metabolic syndrome, current smoker, and skipping breakfast were positively associated with vitamin D deficiency, but high intensity of physical activity and more than 9 hours of sleep duration were negatively associated with vitamin D deficiency (all P < 0.05). CONCLUSIONS: It is important that health professions know that the factors proved in this study are connected to vitamin D deficiency thus provide information and intervention strategies of vitamin D deficiency to old aged people.

The level of vitamin D using the LC-MS/MS method and related factors in healthy Korean postmenopausal women.

AIM: The main purposes of the study were (i) to evaluate serum vitamin D concentration in the forms of 25(OH)D2 , 25(OH)D3 and total 25(OH)D in Korean postmenopausal women using the LC-MS/MS method, which offers increased sensitivity and selectivity; (ii) to determine the relationship between the bone turnover marker, parathyroid hormone (PTH) and 25(OH)D3 , total 25(OH)D separately; and (iii) to determine the factors that may be associated with vitamin D deficiency using body composition analysis and laboratory blood tests. METHOD: A total of 200 postmenopausal women were recruited from November 2012 to March 2014. To control for seasonal ultraviolet exposure time differences in serum 25(OH)D, laboratory tests were performed only from November to March when vitamin D is not synthesized. Independent relationships between 25(OH)D3 , total 25(OH)D and other variables were assessed by multiple regression analysis. RESULTS: The mean serum 25(OH)D2 , 25(OH)D3 and total 25(OH)D levels were 0.51 (±0.44) ng/mL, 14.23 (±7.05) ng/mL and 14.69 (±7.13) ng/mL, respectively. Both 25(OH)D3 and total 25(OH)D were positively correlated with erythrocyte sedimentation rate (ESR), Apo A-I and C-terminal cross-linked telopeptides of type I collagen in Korean postmenopausal women. Both serum 25(OH)D3 and total 25(OH)D were negatively correlated with alkaline phosphatase , PTH and percent body fat. However, osteocalcin showed a negative correlation (r = -0.451; P = 0.041) with only 25(OH)D3 and not with total 25(OH)D (r = -0.417; P = 0.064). CONCLUSION: Both 25(OH)D3 and total 25(OH)D were negatively correlated with PTH, a bone formation marker (alkaline phosphatase) and percent body fat. Both 25(OH)D3 and total 25(OH)D were positively correlated with a bone resorption marker (C-terminal cross-linked telopeptides of type I collagen), ESR and Apo A-I after multiple regression analysis.

Phase 4, Post-Marketing Safety Surveillance of the MF59-Adjuvanted Influenza Vaccines FLUAD® and VANTAFLU® in South Korean Subjects Aged ≥65 Years.

BACKGROUD: Influenza vaccination is recommended for adults aged ≥65 years as they are at high risk of significant morbidity and mortality. This open-label, multicenter, post-marketing surveillance study assessed the safety of the MF59-adjuvanted trivalent inactivated subunit influenza vaccine, which is marketed as FLUAD® and VANTAFLU®, in South Korean subjects aged ≥65 years. MATERIALS AND METHODS: Solicited local and systemic adverse events (AEs) were collected from day 1 to 4 of the study. All unsolicited AEs and serious AEs (SAEs) were recorded from day 1 until study termination (day 29). RESULTS: Of the 770 subjects enrolled (FLUAD®, n = 389; VANTAFLU®, n = 381), 39% overall experienced any solicited AE. Local AEs were reported by 33% of subjects overall; with the most common events being injection-site pain (30%) and tenderness (27%). Systemic AEs were reported by 19% of subjects overall with the most common events being myalgia (11%) and fatigue (8%). CONCLUSION: These results show that the MF59-adjuvanted influenza vaccine known as FLUAD® or VANTAFLU® had acceptable safety profiles in older adults (aged ≥65 years) in South Korea.

Prevalence of Sexual Dysfunction and Associated Risk Factors in Middle-Aged and Elderly Korean Men in Primary Care.

Although several studies have individually investigated the risk factors for erectile dysfunction (ED), premature ejaculation (PE), and late-onset hypogonadism (LOH), few studies have considered ED, PE, and LOH as categories of sexual dysfunction (SD) within the same population. We therefore aimed to investigate the prevalence of SD and its associated risk factors among men in primary care. Study participants were enrolled by 18 family physicians from 15 hospital-based family practices in Korea between August 2010 and May 2011. Participants answered a questionnaire regarding their demographic characteristics and lifestyle factors as well as the Korean versions of the Androgen Deficiency in the Aging Male, the International Index of Erectile Function, and the Premature Ejaculation Diagnostic Tool questionnaires. SD prevalence was 64.9% among study participants who were ≥ 40 years of age. ED prevalence was 43.7%, PE prevalence was 38.6%, and LOH prevalence was 16.8%. SD prevalence was significantly associated with increased age, overweight, hypertension, diabetes, and depression. These findings highlight the importance of screening questions for SD in primary care, especially among older male patients with the identified risk factors.

The Effect of Sleep Quality on the Development of Type 2 Diabetes in Primary Care Patients.

Sleep has important effects on physical and mental health, and sleep disorders are associated with increased mortality and morbidity. This study was conducted to evaluate the relationship between sleep duration or sleep quality and the risk of type 2 diabetes. The FACTS (FAmily CohorT Study in primary care) was established to investigate the relations between familial environment and health which was conducted at 22 family medicine outpatient clinics in general hospitals. Total 563 patients without diabetes who received ≥1 year follow-up examination were included in the analysis. We used the Pittsburgh Sleep Quality Index to determine sleep quality, and a score of ≥5 was considered to define poor sleep quality. Patients taking oral hypoglycemic agents, having a fasting glucose level of >126 mg/dL, or diagnosed with diabetes by physicians were classified as having diabetes. The median follow-up period was 2.5 years. Poor sleep quality was associated with a higher risk of diabetes after adjusting for age, sex, body mass index, income, physical activity, and family history of diabetes (relative risk=2.64; 95% confidence interval, 1.03-6.78). As a risk factor for the development of diabetes, poor sleep quality may independently increase the incidence of diabetes.

The Relationship between a Spouse's Alcohol Use Disorder and Family Communication.

BACKGROUND: Alcohol use disorder (AUD) affects not only an individual's health but also their family. This study was conducted to examine effects of a spouse's AUD on family functioning and family communication. METHODS: We conducted a cross-sectional study using data from 890 participants (445 couples) in a Korean family cohort in primary care. Participants with Alcohol Use Disorders Identification Test in Korea scores of 8 or greater were classified into an AUD group. Family functioning was classified into three groups (balanced, midrange, and extreme) using the Family Adaptability and Cohesion Scale (FACES)-III questionnaire, and then reclassified into two groups (appropriate and extreme groups) for binominal analyses. Family communication was classified into three groups (high, moderate, and low) using the Family Communication Scale, FACES-IV, and also reclassified into two groups (good and poor). RESULTS: There was no significant difference in adaptability and cohesion between both male and female participants with a spouse with AUD and participants with a spouse without AUD. Using multivariate logistic regression to adjust for potential confounders, there was no significant difference in family type and communication between the two groups in males. However, there was a significant decrease in family communication (odds ratio, 2.14; 95% confidence interval, 1.29 to 3.58) in females with a spouse with AUD compared to females with a spouse without AUD, even after adjusting for the participant's own AUD. CONCLUSION: In females, family communication is significantly worse when spouses have AUD. This suggests that a husband's alcohol consumption has negative effects on his wife's family communication.

Bladder recovery by stem cell based cell therapy in the bladder dysfunction induced by spinal cord injury: systematic review and meta-analysis.

BACKGROUND: Bladder dysfunction induced by spinal cord injury (SCI) can become problematic and severely impair the quality of life. Preclinical studies of spinal cord injury have largely focused on the recovery of limb function while neglecting to investigate bladder recovery. OBJECTIVE: The present study was performed to investigate and review the effect of stem cell-based cell therapy on bladder recovery in SCI. METHODS: We conducted a meta-analysis of urodynamic findings of experimental trials that included studies of stem cell-based cell therapy in SCI. Relevant studies were searched using MEDLINE, EMBASE and Cochrane Library (January 1990 - December 2012). Final inclusion was determined by a urodynamic study involving detailed numerical values. Urodynamic parameters for analysis included voiding pressure, residual urine, bladder capacity and non-voiding contraction (NVC). Meta-analysis of the data, including findings from urodynamic studies, was performed using the Mantel-Haenszel method. RESULTS: A total of eight studies were included with a sample size of 224 subjects. The studies were divided into different subgroups by different models of SCI. After a stem cell-based cell therapy, voiding pressure (-6.35, p <0.00001, I2 = 77%), NVC (-3.58, p <0.00001, I2 = 82%), residual urine (-024, p = 0.004, I2 = 95%) showed overall significant improvement. Bladder capacity showed improvement after treatment only in the transection type (-0.23, p = 0.0002, I2 = 0%). CONCLUSION: After stem cell-based cell therapy in SCI, partial bladder recovery including improvement of voiding pressure, NVC, and residual urine was demonstrated. Additional studies are needed to confirm the detailed mechanism and to obtain an ideal treatment strategy for bladder recovery.

A 32 × 32 optical phased array using polysilicon sub-wavelength high-contrast-grating mirrors.

We report on microelectromechanical systems (MEMS)-actuated 32 × 32 optical phased arrays (OPAs) with high fill-factors and microsecond response time. To reduce the mirror weight and temperature-dependent curvature, we use high-contrast-grating (HCG) mirrors comprising a single layer of sub-wavelength polysilicon gratings with 400 nm thickness, 1250 nm pitch, and 570 nm grating bar width. The mirror has a broad reflection band and a peak reflectivity of 99.9% at 1550 nm wavelength. With 20 × 20 µm2 pixels and 2 µm, the OPA has a total aperture of 702 × 702 µm2 and a fill factor of 85%. The OPA is electrostatically controlled by voltage and has a total field of view of ± 2°, an instantaneous field of view (beam width) of 0.14°, and a response time of 3.8 µs. The latter agrees well with the mechanical resonance frequency of the HCG mirror (0.42 MHz).

High speed optical phased array using high contrast grating all-pass filters.

We report a high speed 8x8 optical phased array using tunable 1550 nm all-pass filters with ultrathin high contrast gratings (HCGs) as the microelectromechanical-actuated top reflectors. The all-pass filter design enables a highly efficient phase tuning (1.7 π) with a small actuation voltage (10 V) and actuation displacement of the HCG (50 nm). The microelectromechanical HCG structure facilitates a high phase tuning speed >0.5 MHz. Beam steering is experimentally demonstrated with the optical phased array.

Measuring the improvement in health-related quality of life using King's health questionnaire in non-obese and obese patients with lower urinary tract symptoms after alpha-adrenergic medication: a preliminary study.

BACKGROUND: The efficacy of medical treatment among obese men with lower urinary tract symptoms (LUTS) has been less clear, especially regarding the improvement of QoL. We aimed to investigate the difference in efficacy and consequent satisfaction of life quality after medical treatment of male LUTS according to obesity. METHODS: An 8-week prospective study was performed for a total of 140 patients >50 years old with International Prostate Symptom Scores (IPSS) > 12 points and prostate volume > 20 mL. Obesity was determined by either body mass index (BMI) or waist circumference (WC). Patients were divided into 2 groups according to BMI or WC. Patients received tamsulosin at a dose of 0.4 mg daily for 8 weeks. The changes from baseline in the IPSS, maximal urinary flow rate (Qmax), post-void residual volume, questionnaire of quality of life (QoL), and King's Health Questionnaire (KHQ) were analyzed. RESULTS: Of the 150 enrolled patients, 96 completed the study. Seventy-five patients (78.1%) had BMI ≥ 23 kg/m2, and 24 (25.0%) had WC > 90 cm. Overall, the IPSS, IPSS QoL, and total KHQ showed significant improvement. Obese (BMI ≥ 23 kg/m2) and non-obese (BMI < 23 kg/m2) both showed improvement of the IPSS and IPSS QoL scores, but only the obese (BMI ≥ 23 kg/m2) group showed improvement of the total KHQ score (P < 0.001 vs. P = 0.55). Only the obese (WC > 90 cm) group showed improvement of the IPSS and total KHQ scores (P < 0.001). CONCLUSIONS: Our preliminary study showed the different efficacy of an alpha-blocker for improvement of LUTS and life quality according to obesity. Obese patients, defined by BMI or WC, showed the tendency toward a more favorable improvement of LUTS and life quality. TRIAL REGISTRATION: Current Controlled Trials 2010-058. Registered 2 September 2010 in Soonchunhyang University Hospital.

Hepatic failure induced by cyproterone acetate: A case report and literature review.

Cyproterone acetate (CPA) is an anti-androgenic drug that has been used to manage prostate cancer. The drug is well-tolerated, but has hepatotoxic effects. Hepatic failure induced by CPA is rare urologists tend to overlook its severity. We report a patient with metastatic prostate cancer who developed CPA-induced hepatic failure that manifested as bilirubinuria, which was initially misinterpreted as gross hematuria. The patient died despite receiving critical care. The aim of this study is to sound the alarm about CPA-induced hepatic failure.

Optical phased array using high contrast gratings for two dimensional beamforming and beamsteering.

We have developed a microelectromechanical system (MEMS) optical phased array incorporating a high-index-contrast subwavelength grating (HCG) for beamforming and beamsteering in a range of ± 1.26° × 1.26°. Our approach needs only a thin single-layer HCG made of silicon, considerably improving its speed thanks to the low mass, and is suitable for high optical power applications. The measured resonant frequency of HCG is 0.32 MHz.

Optical beamsteering using an 8 × 8 MEMS phased array with closed-loop interferometric phase control.

We present a high-speed optical beamsteering system based on an 8x8 MEMS phased array. The system incorporates an in situ interferometer that provides a real-time, dynamic measure of the phase of each mirror in the array during beamsteering. A closed-loop phase-control algorithm results in <π/100 mirror phase accuracy and far field beam steering is shown. Stroboscopic measurement capabilities are demonstrated which allow us to show feedforward control to eliminate micromirror ringing.

A wafer-level vacuum package using glass-reflowed silicon through-wafer interconnection for nano/micro devices.

We propose a vacuum wafer-level packaging (WLP) process using glass-reflowed silicon via for nano/micro devices (NMDs). A through-wafer interconnection (TWIn) substrate with silicon vias and reflowed glass is introduced to accomplish a vertical feed-through of device. NMDs are fabricated in the single crystal silicon (SCS) layer which is formed on the TWIn substrate by Au eutectic bonding including Cr adhesion layer. The WLPof the devices is achieved with the capping glass wafer anodically bonded to the SCS layer. In order to demonstrate the successful hermetic packaging, we fabricated the micro-Pirani gauge in the SCS layer, and packaged it in the wafer-level. The vacuum level inside the packaging was measured to be 3.1 Torr with +/- 0.12 Torr uncertainty, and the packaging leakage was not detected during 24 hour after the packaging.

Automated maskless photolithography system for peptide microarray synthesis on a chip.

Maskless photolithographic peptide synthesis was performed on a glass chip using an automated peptide array synthesizer system. The peptide array synthesizer was built in a closed box, which contained optical and fluidic systems. The conditions for peptide synthesis were fully controlled by a computer program. For the peptide synthesis on a glass chip, 20 NVOC-protected amino acids were synthesized. The coupling efficiencies of two model peptide sequences were examined on ACA/APTS and PEG/CHI/GPTS chips. PEG/CHI/GPTS chip gave higher average stepwise yields of GIYWHHY (94%) and YIYGSFK (98%) than those of ACA/APTS chip. To quantify peptide-protein binding affinity, HPQ- or HPM-containing pentapeptides were synthesized on a PEG/CHI/GPTS chip and the binding event of Cy3 labeled-streptavidin was quantified. The peptide sequence of IQHPQ showed highest binding affinity with Cy3 labeled-streptavidin. The results demonstrated that the photolithographic peptide array synthesis method efficiently quantified the binding activities of protein-peptide interactions and it can be used for additional biological assay applications.

Liquid-crystalline semiconducting copolymers with intramolecular donor-acceptor building blocks for high-stability polymer transistors.

The ability to control the molecular organization of electronically active liquid-crystalline polymer semiconductors on surfaces provides opportunities to develop easy-to-process yet highly ordered supramolecular systems and, in particular, to optimize their electrical and environmental reliability in applications in the field of large-area printed electronics and photovoltaics. Understanding the relationship between liquid-crystalline nanostructure and electrical stability on appropriate molecular surfaces is the key to enhancing the performance of organic field-effect transistors (OFETs) to a degree comparable to that of amorphous silicon (a-Si). Here, we report a novel donor-acceptor type liquid-crystalline semiconducting copolymer, poly(didodecylquaterthiophene-alt-didodecylbithiazole), which contains both electron-donating quaterthiophene and electron-accepting 5,5'-bithiazole units. This copolymer exhibits excellent electrical characteristics such as field-effect mobilities as high as 0.33 cm(2)/V.s and good bias-stress stability comparable to that of amorphous silicon (a-Si). Liquid-crystalline thin films with structural anisotropy form spontaneously through self-organization of individual polymer chains as a result of intermolecular interactions in the liquid-crystalline mesophase. These thin films adopt preferential well-ordered intermolecular pi-pi stacking parallel to the substrate surface. This bottom-up assembly of the liquid-crystalline semiconducting copolymer enables facile fabrication of highly ordered channel layers with remarkable electrical stability.