A real-world pharmacovigilance study on cardiovascular adverse events of tisagenlecleucel using machine learning approach.

Chimeric antigen receptor T-cell (CAR-T) therapies are a paradigm-shifting therapeutic in patients with hematological malignancies. However, some concerns remain that they may cause serious cardiovascular adverse events (AEs), for which data are scarce. In this study, gradient boosting machine algorithm-based model was fitted to identify safety signals of serious cardiovascular AEs reported for tisagenlecleucel in the World Health Organization Vigibase up until February 2024. Input dataset, comprised of positive and negative controls of tisagenlecleucel based on its labeling information and literature search, was used to train the model. Then, we implemented the model to calculate the predicted probability of serious cardiovascular AEs defined by preferred terms included in the important medical event list from European Medicine Agency. There were 467 distinct AEs from 3,280 safety cases reports for tisagenlecleucel, of which 363 (77.7%) were classified as positive controls, 66 (14.2%) as negative controls, and 37 (7.9%) as unknown AEs. The prediction model had area under the receiver operating characteristic curve of 0.76 in the test dataset application. Of the unknown AEs, six cardiovascular AEs were predicted as the safety signals: bradycardia (predicted probability 0.99), pleural effusion (0.98), pulseless electrical activity (0.89), cardiotoxicity (0.83), cardio-respiratory arrest (0.69), and acute myocardial infarction (0.58). Our findings underscore vigilant monitoring of acute cardiotoxicities with tisagenlecleucel therapy.

The Influence of Tacrolimus on Cellular Morphology, Cellular Viability, Osteogenic Differentiation, and mRNA Expression within Stem Cell Spheroids.

Background and Objectives: Tacrolimus is a macrolide lactone compound derived from the bacterium Streptomyces tsukubensis, widely known as an immunosuppressant. In basic research, the effects of tacrolimus on osteogenic differentiation have been tested using mesenchymal stem cells. In this study, tacrolimus's effects on the cellular survival and osteogenic differentiation of stem cell spheroids were investigated. Materials and Methods: Concave microwells were used to form stem cell spheroids in the presence of tacrolimus at final concentrations of 0 µg/mL, 0.1 µg/mL, 1 µg/mL, 10 µg/mL, and 100 µg/mL. A microscope was used to test cellular vitality qualitatively, and an assay kit based on water-soluble tetrazolium salt was used to measure cellular viability quantitatively. Alkaline phosphatase activity and an anthraquinone dye test for measuring calcium deposits were used to assess osteogenic differentiation. To assess the expression of osteogenic differentiation, a quantitative polymerase chain reaction, Western blot, and RNA sequencing were performed. Results: Spheroids across all concentrations maintained a relatively uniform and spherical shape. Cell viability assay indicated that tacrolimus, up to a concentration of 100 µg/mL, did not significantly impair cell viability within spheroids cultured in osteogenic media. The increase in calcium deposition, particularly at lower concentrations of tacrolimus, points toward an enhancement in osteogenic differentiation. There was an increase in COL1A1 expression across all tacrolimus concentrations, as evidenced by the elevated mean and median values, which may indicate enhanced osteogenic activity. Conclusions: This study showed that tacrolimus does not significantly impact the viability of stem cell spheroids in osteogenic media, even at high concentrations. It also suggests that tacrolimus may enhance osteogenic differentiation, as indicated by increased calcium deposition and COL1A1 expression. These findings advance our understanding of tacrolimus's potential roles in tissue repair, regeneration, and stem cell-based therapeutic applications.

Mad2B forms a complex with Cdc20, Cdc27, Rev3 and Rev1 in response to cisplatin-induced DNA damage.

Mitotic arrest deficient 2 like 2 (Mad2L2, also known as Mad2B), the human homologue of the yeast Rev7 protein, is a regulatory subunit of DNA polymerase ζ that shares high sequence homology with Mad2, the mitotic checkpoint protein. Previously, we demonstrated the involvement of Mad2B in the cisplatin-induced DNA damage response. In this study, we extend our findings to show that Mad2B is recruited to sites of DNA damage in human cancer cells in response to cisplatin treatment. We found that in undamaged cells, Mad2B exists in a complex with Polζ-Rev1 and the APC/C subunit Cdc27. Following cisplatin-induced DNA damage, we observed an increase in the recruitment of Mad2B and Cdc20 (the activators of the APC/C), to the complex. The involvement of Mad2B-Cdc20-APC/C during DNA damage has not been reported before and suggests that the APC/C is activated following cisplatin-induced DNA damage. Using an in vitro ubiquitination assay, our data confirmed Mad2B-dependent activation of APC/C in cisplatin-treated cells. Mad2B may act as an accelerator for APC/C activation during DNA damage response. Our data strongly suggest a role for Mad2B-APC/C-Cdc20 in the ubiquitination of proteins involved in the DNA damage response.

Trends of polypharmacy among older people in Asia, Australia and the United Kingdom: a multinational population-based study.

BACKGROUND: Polypharmacy among older people represents a global challenge due to its association with adverse drug events. The reported prevalence of polypharmacy varies widely across countries, and is particularly high in Asian countries. However, there is no multinational study using standardised measurements exploring variations in prescribing trends. OBJECTIVE: To compare polypharmacy trends in older people in Asia, Australia and the United Kingdom. DESIGN: Multinational, retrospective, time-trend, observational study using a common study protocol. SETTING: Outpatient and community settings. SUBJECTS: All individuals aged ≥ 65 years between 2013 and 2016. METHODS: We defined polypharmacy as the concomitant use of ≥5 medications for ≥45 days per year. We estimated the annual prevalence of polypharmacy and calculated average annual percentage change (AAPC) to assess the time trends. RESULTS: A total of 1.62 million individuals were included in this study. The highest prevalence of polypharmacy was observed in Hong Kong (46.4%), followed by Taiwan (38.8%), South Korea (32.0%), the United Kingdom (23.5%) and Australia (20.1%) in 2016. For the time trend, the Asian region showed a steady increase, particularly in Hong Kong and South Korea (AAPC: Hong Kong, 2.7%; South Korea, 1.8%; Taiwan, 1.0%). However, Australia and the United Kingdom showed a decreasing trend (Australia, -4.9%; the United Kingdom, -1.1%). CONCLUSIONS: Polypharmacy prevalence in older people was higher in Hong Kong, Taiwan and South Korea, with an increasing trend over time, compared with Australia and the United Kingdom. Our findings underline the necessity to monitor polypharmacy among older people in Asia by conducting government-level interventions and introducing medicine-optimisation strategies.

Inactivation of Mad2B Enhances Apoptosis in Human Cervical Cancer Cell Line upon Cisplatin-Induced DNA Damage.

Mad2B (Mad2L2), the human homolog of the yeast Rev7 protein, is a regulatory subunit of DNA polymerase ζ that shares sequence similarity with the mitotic checkpoint protein Mad2A. Previous studies on Mad2B have concluded that it is a mitotic checkpoint protein that functions by inhibiting the anaphase-promoting complex/cyclosome (APC/C). Here, we demonstrate that Mad2B is activated in response to cisplatin-induced DNA damage. Mad2B co-localizes at nuclear foci with DNA damage markers, such as proliferating cell nuclear antigen and gamma histone H2AX (γ-H2AX), following cisplatin-induced DNA damage. However, unlike Mad2A, the binding of Mad2B to Cdc20 does not inhibit the activity of APC/C in vitro. In contrast to Mad2A, Mad2B does not localize to kinetochores or binds to Cdc20 in spindle assembly checkpoint-activated cells. Loss of the Mad2B protein leads to damaged nuclei following cisplatin-induced DNA damage. Mad2B/Rev7 depletion causes the accumulation of damaged nuclei, thereby accelerating apoptosis in human cancer cells in response to cisplatin-induced DNA damage. Therefore, our results suggest that Mad2B may be a critical modulator of DNA damage response.

Risk Factors of Pertussis Among Older Adults in South Korea: A Nationwide Health Data-Based Case-Control Study.

INTRODUCTION: To better understand the conditions associated with pertussis diagnosis among older adults in South Korea, a matched case-control study was conducted of individuals ≥ 50 years diagnosed with pertussis between 2009 and 2018. METHODS: Pertussis cases were identified using the nationwide Health Insurance Review and Assessment service (HIRA) database. Each case was then matched to up to 10 controls identified using the National Health Insurance Service-National Sample Cohort (NHIS-NSC) by age, sex, and geographic region at index date. In the 12 months and 30 days prior to index date, the presence of clinical characteristics previously reported to be related to pertussis and pertussis-like conditions were assessed, respectively. A conditional multivariate logistic regression model was then used to calculate odds ratios (ORs) of pertussis diagnosis, adjusted for each of the characteristics. RESULTS: Pertussis cases (n = 1004) generally demonstrated a higher prevalence of comorbidities compared to controls (n = 9710). Pre-existing asthma and chronic obstructive pulmonary disease (COPD) within 12 months of index date were associated with a two-fold increased risk of pertussis with adjusted ORs (95% confidence interval) of 2.08 (1.68-2.58) and 2.32 (1.59-3.39), respectively. Gastroesophageal reflux disease [GERD; 2.67 (2.23-3.19)], cancer [1.68 (1.23-2.31)], cardiovascular disease [1.62 (1.31-2.00)], renal disease [1.56 (1.12-2.16)], autoimmune disease [1.50 (1.25-1.79)], and hyperlipidemia [1.43 (1.16-1.77)] were also associated with pertussis diagnosis. Finally, acute respiratory events within 30 days prior to index date, such as pneumonia, acute bronchitis, and upper respiratory tract infection (URTI), were highly associated with increased odds of pertussis diagnosis [adjusted ORs of 8.28 (5.10-13.44), 4.86 (3.84-6.14), and 2.90 (2.30-3.67), respectively]. CONCLUSIONS: This study's findings complement and expand upon previous studies on the adult pertussis population, generating real-world data to describe underlying clinical characteristics of those diagnosed with pertussis in South Korea.

Impact of 17ß-Estradiol on the Shape, Survival, Osteogenic Transformation, and mRNA Expression of Gingiva-Derived Stem Cell Spheroids.

Background and Objectives: Mesenchymal stem cells hold promise for tissue regeneration, given their robust growth and versatile differentiation capabilities. An analysis of bone marrow-sourced mesenchymal stem cell proliferation showed that 17ß-estradiol could enhance their growth. This study aims to investigate the influence of 17ß-estradiol on the shape, survival, osteogenic differentiation, and mineralization of human mesenchymal stem cells. Materials and Methods: Spheroids made from human gingiva-derived stem cells were cultivated with varying concentrations of 17ß-estradiol: 0, 0.01, 0.1, 1, and 10 nM. Morphology was assessed on days 1, 3, and 5. The live/dead kit assay was employed on day 3 for qualitative cell viability, while cell counting kit-8 was used for quantitative viability assessments on days 1, 3, and 5. To evaluate the osteogenic differentiation of the spheroids, a real-time polymerase chain reaction assessed the expressions of RUNX2 and COL1A1 on day 7. Results: The stem cells formed cohesive spheroids, and the inclusion of 17ß-estradiol did not noticeably alter their shape. The spheroid diameter remained consistent across concentrations of 0, 0.01, 0.1, 1, and 10 nM of 17ß-estradiol. However, cellular viability was boosted with the addition of 1 and 10 nM of 17ß-estradiol. The highest expression levels for RUNX2 and COL1A1 were observed with the introduction of 17ß-estradiol at 0.1 nM. Conclusions: In conclusion, from the results obtained, it can be inferred that 17ß-estradiol can be utilized for differentiating stem cell spheroids. Furthermore, the localized and controlled use, potentially through localized delivery systems or biomaterials, can be an area of active research. While 17ß-estradiol holds promise for enhancing stem cell applications, any clinical use requires a thorough understanding of its mechanisms, careful control of its dosage and delivery, and extensive testing to ensure safety and efficacy.

Comparative Treatment Persistence with Bone-Targeting Agents Among Asian Patients with Bone Metastases from Solid Tumors: A Multinational Retrospective Cohort Study.

BACKGROUND: The efficacy of bone-targeting agents has been confirmed, but the generalizability of results to Asia is in question. OBJECTIVE: We aimed to evaluate and compare treatment persistence and re-initiation with different bone-targeting agents among patients with bone metastases from solid tumors. METHODS: This population-based cohort study included patients with bone metastasis with breast, lung, or prostate cancer who initiated bone-targeting agents, including denosumab, zoledronic acid, and pamidronate in Taiwan (2013-17), Hong Kong (2013-17), and Korea (2012-16). We described the patients' persistence with bone-targeting agents, by evaluating the interruption probability, and compared risks of treatment interruption. The rates of re-initiation with index bone-targeting agents were evaluated. RESULTS: We included 5127 patients (denosumab: 3440, zoledronic acid: 1210, pamidronate: 477) from Taiwan, 883 patients (denosumab: 458, zoledronic acid: 357, pamidronate: 68) from Hong Kong, and 4800 patients (zoledronic acid: 4068, pamidronate: 732) from Korea. Compared with zoledronic acid, denosumab had a lower risk of interruption in Taiwan (adjusted hazard ratio: 0.44; 95% confidence interval 0.40-0.48) and Hong Kong (0.36; 0.28-0.45). However, pamidronate was more likely to be interrupted than zoledronic acid in Taiwan (1.31; 1.11-1.54) and Korea (2.06; 1.83-2.32), but not in Hong Kong (1.13; 0.71-1.78). After discontinuation, original treatments with denosumab in Taiwan and zoledronic acid in Hong Kong were more likely to be resumed, while in Korea, the rates were similar among the bisphosphonates. CONCLUSIONS: Denosumab was associated with a lower risk of interruption than bisphosphonates in patients with bone metastases in Taiwan and Hong Kong. Further investigations may be required to verify patients' actual reasons for discontinuation.

Site-Selective Antibody-Drug Conjugation by a Proximity-Driven S to N Acyl Transfer Reaction on a Therapeutic Antibody.

Immunoglobulin Gs (IgGs) contain many Lys and Cys residues, which results in an unwanted complex product mixture with conventional drug conjugation methods. We selectively acylated the ε-NH2 of K248 on trastuzumab using an IgG Fc-binding peptide (FcBP) equipped with a 5-norbornene-2-carboxylic acid thioester (AbClick-1). AbClick-1 locates its thioester close to the ε-NH2 of K248 while binding to trastuzumab. Consequently, the thioester underwent proximity-driven selective acylation of ε-NH2 through an S to N acyl transfer reaction. Furthermore, N-tert-butyl maleimide accelerated the cross-linking reaction with an approximately 95% yield of the desired product by scavenging the byproduct (FcBP-SH). Only K248 was modified selectively with the 5-norbornene-2-carbonyl group, which was further modified by click reaction to afford an antibody-drug conjugate (ADC) with two drugs per antibody. The resulting ADCs showed remarkable in vitro and in vivo anticancer activity. Our results demonstrate that a thioester is a promising chemical entity for proximity-driven site-selective conjugation of antibodies.

Bone-targeting agents in major solid tumour metastases: a multinational cohort study.

OBJECTIVE: To describe the epidemiology, clinical characteristics and utilisation patterns of bone-targeting agents (BTAs) in patients with bone metastases from breast, prostate and lung cancer. METHODS: This is a multinational retrospective cohort study including patients with three major solid tumours (breast, prostate and lung cancer) and newly initiated on BTAs (ie, denosumab, zoledronic acid and pamidronate). Records were retrieved from nationwide health databases from Hong Kong and Taiwan (HK and TW: 2013-2017) and Korea (KR: 2012-2016). Descriptive analyses included the annual incidence rates of bone metastases and the cumulative incidence curves of BTA initiation. We used Sankey diagrams to visualise the dynamic BTA utilisation patterns. RESULTS: The annual incidence rate of bone metastases ranged from 3.5% to 4.5% in TW, from 9.6% to 10.3% in HK and from 2.9% to 3.8% in KR. We identified 14.1% (5127), 9.3% (883) and 9.4% (4800) of patients with bone metastases newly initiated on BTAs in TW, HK and KR, respectively. The most frequently used BTA in TW (67.1%) and HK (51.9%) was denosumab, while in KR (84.8%) it was zoledronic acid. Sankey diagrams indicated the proportion of patients remaining on denosumab was highest in TW and HK, while it was zoledronic acid in KR. Specifically, in TW, patients who were on bisphosphonates or had discontinued treatment frequently switched to or reinitiated denosumab. CONCLUSIONS: We found the rate of BTA utilisation remained low across all sites and tumour types in recent years. The dynamic utilisation patterns of BTAs provide better understanding of the treatment landscape for future evaluation of associated outcomes of patients.

Survival outcomes of patients with nonsmall cell lung cancer concomitantly receiving proton pump inhibitors and immune checkpoint inhibitors.

Recent evidence suggests that gut microbiota dysbiosis adversely affects the efficacy of immune checkpoint inhibitors (ICIs). Our objective was to investigate the association between concomitant use of proton pump inhibitors (PPIs) and ICIs, and poor prognosis in patients with nonsmall cell lung cancer (NSCLC). We conducted a cohort study using a completely enumerated lung cancer cohort from a nationwide healthcare database in South Korea. We identified 2963 patients treated with ICIs as second-line or later therapy for stage ≥IIIB NSCLC. PPI use was ascertained within 30-days before and on the date of ICI initiation, and nonuse was defined as no prescription of PPIs during this period. Using national vital statistics in South Korea, we assessed the risk of all-cause mortality associated with concomitant PPI use through a propensity score-matched Cox proportional hazard model. Among 1646 patients included after 1:1 propensity score-matching, concomitant PPI use was associated with a 28% increased risk of all-cause mortality, compared to nonuse (adjusted hazard ratio [HR] 1.28; 95% confidence intervals [CIs], 1.13-1.46). We observed an increased risk when we restricted the analysis to new users of PPI (adjusted HR = 1.64; 95% CI = 1.25-2.17). Subgroup analysis showed that PPI use was associated with high mortality risk among patients with viral hepatitis (adjusted HR = 2.72; 95% CI = 1.54-4.78; Pinteraction = .048). Our study indicates that PPI use is associated with poor prognosis in NSCLC patients treated with ICIs. Further prospective studies are required to determine the risk-benefit balance of concomitant use of PPIs and ICIs.

Treatment pattern in postmenopausal women with osteoporosis: a population-based cohort study in South Korea.

INTRODUCTION: The treatment landscape of postmenopausal osteoporosis (OP) in an Asian population is yet to be explored. MATERIALS AND METHODS: We conducted a retrospective cohort study to explore treatment patterns and characteristics associated with treatment interruption in postmenopausal women diagnosed with OP between 2008 and 2014. Treatment pattern assessment included the initial distribution of OP medications and treatment interruption rate according to the treatment groups during a 3-year follow-up period. We used multivariate logistic regression to estimate odds ratio (OR) and 95% confidence interval (CI) to identify factors associated with treatment interruption. RESULTS: Of 21,813 patients, 87.9% initiated oral bisphosphonates (BP), followed by ibandronate intravenous (IV; 5.4%), selective estrogen receptor modulators (SERMs; 5.2%), pamidronate IV (1.4%) and zoledronic acid (0.06%). Treatment interruption was most notable in the first year of treatment, with cumulative treatment interruption rates highest for oral BP (76.3%) and lowest for pamidronate IV (50.5%). Compared to oral BP users, users of ibandronate IV (OR 0.34, 95% CI 0.30-0.39), pamidronate IV (0.49, 0.39-0.63), zoledronic acid (0.26, 0.09-0.77), and SERMs (0.50, 0.44-0.57) were less likely to interrupt treatment. Of characteristics assessed, presence of rheumatoid arthritis increased the odds of treatment interruption in ibandronate IV group (3.94, 2.12-7.33), and concomitant use of glucocorticoids for oral BP (1.11, 1.03-1.19) and pamidronate IV (2.04, 1.06-3.93) groups, respectively. CONCLUSION: Given the frequent treatment interruptions across all OP medications, our findings on the factors associated with treatment interruption will serve to implement targeted interventions in reinforcing persistence to OP treatment.

Exposure to long-term evolution radiofrequency electromagnetic fields decreases neuroblastoma cell proliferation via Akt/mTOR-mediated cellular senescence.

The aim of this study was to examine the potential effects of long-term evolution (LTE) radiofrequency electromagnetic fields (RF-EMF) on cell proliferation using SH-SY5Y neuronal cells. The growth rate and proliferation of SH-SY5Y cells were significantly decreased upon exposure to 1760 MHz RF-EMF at 4 W/kg specific absorption rate (SAR) for 4 hr/day for 4 days. Cell cycle analysis indicated that the cell cycle was delayed in the G0/G1 phase after RF-EMF exposure. However, DNA damage or apoptosis was not involved in the reduced cellular proliferation following RF-EMF exposure because the expression levels of histone H2A.X at Ser139 (γH2AX) were not markedly altered and the apoptotic pathway was not activated. However, SH-SY5Y cells exposed to RF-EMF exhibited a significant elevation in Akt and mTOR phosphorylation levels. In addition, the total amount of p53 and phosphorylated-p53 was significantly increased. Data suggested that Akt/mTOR-mediated cellular senescence led to p53 activation via stimulation of the mTOR pathway in SH-SY5Y cells. The transcriptional activation of p53 led to a rise in expression of cyclin-dependent kinase (CDK) inhibitors p21 and p27. Further, subsequent inhibition of CDK2 and CDK4 produced a fall in phosphorylated retinoblastoma (pRb at Ser807/811), which decreased cell proliferation. Taken together, these data suggest that exposure to RF-EMF might induce Akt/mTOR-mediated cellular senescence, which may delay the cell cycle without triggering DNA damage in SH-SY5Y neuroblastoma cells.

The Protective Effects of EMF-LTE against DNA Double-Strand Break Damage In Vitro and In Vivo.

With the rapid growth of the wireless communication industry, humans are extensively exposed to electromagnetic fields (EMF) comprised of radiofrequency (RF). The skin is considered the primary target of EMFs given its outermost location. Recent evidence suggests that extremely low frequency (ELF)-EMF can improve the efficacy of DNA repair in human cell-lines. However, the effects of EMF-RF on DNA damage remain unknown. Here, we investigated the impact of EMF-long term evolution (LTE, 1.762 GHz, 8 W/kg) irradiation on DNA double-strand break (DSB) using the murine melanoma cell line B16 and the human keratinocyte cell line HaCaT. EMF-LTE exposure alone did not affect cell viability or induce apoptosis or necrosis. In addition, DNA DSB damage, as determined by the neutral comet assay, was not induced by EMF-LTE irradiation. Of note, EMF-LTE exposure can attenuate the DNA DSB damage induced by physical and chemical DNA damaging agents (such as ionizing radiation (IR, 10 Gy) in HaCaT and B16 cells and bleomycin (BLM, 3 µM) in HaCaT cells and a human melanoma cell line MNT-1), suggesting that EMF-LTE promotes the repair of DNA DSB damage. The protective effect of EMF-LTE against DNA damage was further confirmed by attenuation of the DNA damage marker γ-H2AX after exposure to EMF-LTE in HaCaT and B16 cells. Most importantly, irradiation of EMF-LTE (1.76 GHz, 6 W/kg, 8 h/day) on mice in vivo for 4 weeks reduced the γ-H2AX level in the skin tissue, further supporting the protective effects of EMF-LTE against DNA DSB damage. Furthermore, p53, the master tumor-suppressor gene, was commonly upregulated by EMF-LTE irradiation in B16 and HaCaT cells. This finding suggests that p53 plays a role in the protective effect of EMF-LTE against DNA DSBs. Collectively, these results demonstrated that EMF-LTE might have a protective effect against DNA DSB damage in the skin, although further studies are necessary to understand its impact on human health.

Activation of matrix metalloproteinases and FoxO3a in HaCaT keratinocytes by radiofrequency electromagnetic field exposure.

As the skin is the largest body organ and critically serves as a barrier, it is frequently exposed and could be physiologically affected by radiofrequency electromagnetic field (RF-EMF) exposure. In this study, we found that 1760 MHz RF-EMF (4.0 W/kg specific absorption rate for 2 h/day during 4 days) exposure could induce intracellular reactive oxygen species (ROS) production in HaCaT human keratinocytes using 2',7'-dichlorofluorescin diacetate fluorescent probe analysis. However, cell growth and viability were unaffected by RF-EMF exposure. Since oxidative stress in the skin greatly influences the skin-aging process, we analyzed the skin senescence-related factors activated by ROS generation. Matrix metalloproteinases 1, 3, and 7 (MMP1, MMP3, and MMP7), the main skin wrinkle-related proteins, were significantly increased in HaCaT cells after RF-EMF exposure. Additionally, the gelatinolytic activities of secreted MMP2 and MMP9 were also increased by RF-EMF exposure. FoxO3a (Ser318/321) and ERK1/2 (Thr 202/Tyr 204) phosphorylation levels were significantly increased by RF-EMF exposure. However, Bcl2 and Bax expression levels were not significantly changed, indicating that the apoptotic pathway was not activated in keratinocytes following RF-EMF exposure. In summary, our findings show that exposure to 1760 MHz RF-EMF induces ROS generation, leading to MMP activation and FoxO3a and ERK1/2 phosphorylation. These data suggest that RF-EMF exposure induces cellular senescence of skin cells through ROS induction in HaCaT human keratinocytes.

Photoconjugation of an Fc-Specific Peptide Enables Efficient DAR 2 Antibody-Drug Conjugate Formation.

Antibody-drug conjugates (ADCs) in current clinical usage have been constructed via the nonspecific conjugation of drugs to antibodies, rendering the manufacturing processes difficult. In this study, a high-affinity IgG Fc-binding peptide equipped with a photoreactive amino acid was developed and successfully conjugated to Glu-382 of trastuzumab in a site-specific manner. The resulting conjugate was employed to generate a DAR 2 ADC product using click chemistry.

Decreased dopamine in striatum and difficult locomotor recovery from MPTP insult after exposure to radiofrequency electromagnetic fields.

Concern is growing about possible neuronal effects of human exposure to radiofrequency electromagnetic fields because of the increasing usage of cell phones and the close proximity of these devices to the brain when in use. We found that exposure to a radiofrequency electromagnetic field (RF-EMF) of 835 MHz (4.0 W/kg specific absorption rate [SAR] for 5 h/day for 12 weeks) affects striatal neurons in C57BL/6 mice. The number of synaptic vesicles (SVs) in striatal presynaptic boutons was significantly decreased after RF-EMF exposure. The expression levels of synapsin I and II were also significantly decreased in the striatum of the RF-EMF-exposed group. RF-EMF exposure led to a reduction in dopamine concentration in the striatum and also to a decrease in the expression of tyrosine hydroxylase in striatal neurons. Furthermore, in behavioral tests, exposure to RF-EMF impeded the recovery of locomotor activities after repeated treatments with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). These results suggest that the observed decrease in dopamine concentration in the striatum was caused by both a reduction in the number of dopaminergic neurons and a decline in the number of SVs. The decreased dopamine neuron numbers and concentration seen after RF-EMF exposure would have caused the difficult recovery after MPTP treatment. In summary, our results strongly suggest that exposing the brain to RF-EMF can decrease the number of SVs and dopaminergic neurons in the striatum. These primary changes impair the recovery of locomotor activities following MPTP damage to the striatum.

Early exposure to radiofrequency electromagnetic fields at 1850 MHz affects auditory circuits in early postnatal mice.

In the present study, we measured the spontaneous post synaptic currents (sPSCs) at the post synaptic principle cells of the medial nucleus of the trapezoid body (MNTB) in early postnatal mice after exposure to 1850 MHz radiofrequency electromagnetic fields (RF-EMF). sPSC frequencies and amplitudes were significantly increased in the RF-EMF exposed group. Moreover, the number of synaptic vesicles in the calyx of Held was significantly increased in presynaptic nerve terminals. Following RF-EMF exposure, the number of docking synaptic vesicles in the active zone increased, thereby expanding the total length of the presynaptic active zone in the calyx of Held. These data suggest that the increased sPSCs are a result of greater synaptic vesicle release from presynaptic nerves. However, we found no morphological changes in the inner hair cell ribbon synapses. Further, there were no significant changes in the hearing threshold of the auditory brainstem response at postnatal day 15. Our results indicate that exposure to RF-EMF at an early postnatal stage might directly affect brainstem auditory circuits, but it does not seem to alter general sound perception.

Label-Free Detection of Protein Tyrosine Phosphatase 1B (PTP1B) by Using a Rationally Designed Förster Resonance Energy Transfer (FRET) Probe.

A highly selective detection method of native protein tyrosine phosphatase 1B (PTP1B) is described using a target specific probe equipped with 1-naphthylamine (λex =330 nm, λem =445 nm). Irradiation of a mixture of PTP1B and Probe 1 with ultraviolet light of 280 nm (corresponding to PTP1B excitation maximum) resulted in significant fluorescence increase at 445 nm, following FRET characteristics. This phenomenon does not occur with other closely related phosphatases or cellular abundant alkaline phosphatase (APP). Probe 1, the most potent and selective probe, was found to competitively inhibit PTP1B (Ki ≈42 nm), whereas APP inhibition was found to be in the low micromolar range. Furthermore, Probe 1 discriminates between PTP1B and several other phosphatases. Here, we report real-time label-free FRET detection of pure PTP1B as well as induced human PTP1B in Escherichia coli cell lysate. In contrast to 6,8-difluoro-4-methylumbelliferyl phosphate (DiFMUP), a representative fluorescence turn-on PTP substrate, our FRET probe successfully differentiated human cervical carcinoma cell lysate, SiHa, which has a high expression level of PTP1B, from PTP1B-knockdown SiHa cell lysate (that is, siRNA was used for PTP1B knockdown).