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The asymmetric cross-coupling of unsaturated bonds, hampered by their comparable polarity and reactivity, as well as the scarcity of efficient catalytic systems capable of diastereo- and enantiocontrol, presents a significant hurdle in organic synthesis. In this study, we introduce a highly adaptable photochemical cobalt catalysis framework that facilitates chemo- and stereoselective reductive cross-couplings between common aldehydes with a broad array of carbonyl and iminyl compounds, including N-acylhydrazones, aryl ketones, aldehydes, and α-keto esters. Our methodology hinges on a synergistic mechanism driven by photoredox-induced single-electron reduction and subsequent radical-radical coupling, all precisely guided by a chiral cobalt catalyst. Various optically enriched ß-amino alcohols and unsymmetrical 1,2-diol derivatives (80 examples) have been synthesized with good yields (up to 90% yield) and high stereoselectivities (up to >20:1 dr, 99% ee). Of particular note, this approach accomplishes unattainable photochemical asymmetric transformations of aldehydes with disparate carbonyl partners without reliance on any external photosensitizer, thereby further emphasizing its versatility and cost-efficiency.
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OBJECTIVE: Mesenchymal stem cells (MSCs) can treat osteoarthritis (OA), but their therapeutic efficacy is poor to date due to low migration efficiency. This study aimed to determine whether ultrasound-targeted microbubble destruction (UTMD) could ameliorate cartilage repair efficiency through facilitating the migration of MSCs via hypoxia-inducible factor-1α (HIF-1α)-mediated glycolysis regulatory pathway in OA model rats. METHODS: OA rats were treated with MSCs alone or in combination with UTMD, respectively, for 4 weeks. Cartilage histopathology, MSCs migration efficiency, von Frey fiber thresholds, and the expression levels of collagen II and MMP-13 were measured. Further, MSCs were extracted from the bone marrow of rats, cocultured with osteoarthritic chondrocytes, transfected to siRNA-HIF-1α, and subjected to UTMD for 4 days. Glucose consumption, lactate production, and cell migration efficiency were assessed. The protein expression levels of HIF-1α, HK2, PKM2, and GLUT1 were measured, respectively. RESULTS: In OA rat model, NC-MSCs + UTMD improved migration efficiency, increased collagen II expression, decreased MMP-13 expression, and delayed osteoarthritis progression. Silencing HIF-1α attenuated the effects induced by UTMD. In vitro, UTMD led to increases in MSC activity and migration, glucose consumption, lactate production, and the protein expression of HIF-1α, HK2, PKM2, and GLUT1 expression, all of which were reversed upon HIF-1α silencing. CONCLUSION: UTMD enhances MSCs migration and improves cartilage repair efficiency through the HIF-1α-mediated glycolytic regulatory pathway, providing a novel therapy strategy for knee osteoarthritis.
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Movimento Celular , Glicólise , Subunidade alfa do Fator 1 Induzível por Hipóxia , Células-Tronco Mesenquimais , Microbolhas , Osteoartrite , Ratos Sprague-Dawley , Animais , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/citologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Ratos , Osteoartrite/metabolismo , Osteoartrite/terapia , Osteoartrite/patologia , Transplante de Células-Tronco Mesenquimais/métodos , Masculino , Ondas Ultrassônicas , Cartilagem Articular/metabolismo , Cartilagem Articular/patologia , Condrócitos/metabolismo , Células CultivadasRESUMO
Integrating traits across above- and belowground organs offers comprehensive insights into plant ecology, but their various functions also increase model complexity. This study aimed to illuminate the interspecific pattern of whole-plant trait correlations through a network lens, including a detailed analysis of the root system. Using a network algorithm that allows individual traits to belong to multiple modules, we characterize interrelations among 19 traits, spanning both shoot and root phenology, architecture, morphology, and tissue properties of 44 species, mostly herbaceous monocots from Northern Ontario wetlands, grown in a common garden. The resulting trait network shows three distinct yet partially overlapping modules. Two major trait modules indicate constraints of plant size and form, and resource economics, respectively. These modules highlight the interdependence between shoot size, root architecture and porosity, and a shoot-root coordination in phenology and dry-matter content. A third module depicts leaf biomechanical adaptations specific to wetland graminoids. All three modules overlap on shoot height, suggesting multifaceted constraints of plant stature. In the network, individual-level traits showed significantly higher centrality than tissue-level traits do, demonstrating a hierarchical trait integration. The presented whole-plant, integrated network suggests that trait covariation is essentially function-driven rather than organ-specific.
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Integrating optoelectronic devices with various functions into a monolithic chip is a popular research frontier. The top-down integration scheme on silicon-based III-nitride wafers has unique advantages. A monolithic III-nitride on-chip system with lighting source, electrical absorption modulator, waveguide and photodetector with the same structure were designed and fabricated to discover the asymmetry of photon emission and absorption in quantum well diode. The characteristics of the chip were characterized in detail and three different spectral redshifts were observed in the experiment. Results revealed that the asymmetric absorption causes spectral redshift in a quantum well diode, and self-absorption is a fundamental and universal phenomenon in quantum wells. This work provides an important reference for future III-nitride optoelectronic integration.
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Insects are the most widely distributed and successful animals on the planet. A large number of insects are capable of flight with functional wings. Wing expansion is an important process for insects to achieve functional wings after eclosion and healthy genital morphology is crucial for adult reproduction. Myofilaments are functional units that constitute sarcomeres and trigger muscle contraction. Here, we identified four myofilament proteins, including Myosin, Paramyosin, Tropomyosin and Troponin T, from the wing pads of nymphs in the American cockroach, Periplaneta americana. RNAi-mediated knockdown of Myosin, Paramyosin, Tropomyosin and Troponin T in the early stage of final instar nymphs caused a severely curly wing phenotype in the imaginal moult, especially in the Paramyosin and Troponin T knockdown groups, indicating that these myofilament proteins are involved in controlling wing expansion behaviours during the nymph-adult transition. In addition, the knockdown resulted in abnormal external genitalia, caused ovulation failure, and affected male accessory gland development. Interestingly, the expression of myofilament genes was induced by methoprene, a juvenile hormone (JH) analogue, and decreased by the depletion of the JH receptor gene Met. Altogether, we have determined that myofilament genes play an important role in promoting wing expansion and maintaining adult genitalia morphology, and their expression is induced by JH signalling. Our data reveal a novel mechanism by which wing expansion is regulated by myofilaments and the functions of myofilaments are involved in maintaining genitalia morphology.
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Periplaneta , Feminino , Masculino , Animais , Periplaneta/genética , Periplaneta/metabolismo , Miofibrilas , Tropomiosina/genética , Tropomiosina/metabolismo , Troponina T/metabolismo , Metamorfose Biológica , Insetos , Hormônios Juvenis/metabolismo , NinfaRESUMO
When an AlGaInP quantum well (QW) diode is biased with a forward voltage and illuminated with an external shorter-wavelength light beam, the diode is in a superposition state of both light emission and detection. The two different states take place simultaneously, and both the injected current and the generated photocurrent begin to mix. Here, we make use of this intriguing effect and integrate an AlGaInP QW diode with a programmed circuit. The AlGaInP QW diode with the dominant emission peak wavelength centered around 629.5â nm is excited by a 620-nm red-light source. The photocurrent is then extracted as a feedback signal to regulate the light emission of the QW diode in real time without an external or monolithically integrated photodetector, paving a feasible way to autonomously adjust the brightness of the QW diode for intelligent illumination in response to changes in the environmental light condition.
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Lightweight, low-cost, and simple systems for magnetic field sensing are in high demand. Here, we demonstrate such a magnetic field sensing system by integrating a light source, detector, magnetic fluid (MF), and plastic optical fiber (POF). Two bifunctional AlGaInP diodes with identical multiple-quantum well structures separately function as the light source and the detector of the sensing system due to the partial overlap between the electroluminescence and responsivity spectra. Magnetic field sensing is realized by changing the amount of reflected light due to the change in reflection coefficient of the POF/MF interface caused by the ambient magnetic field. The chip-integrated POF magnetic field sensor exhibits a reliable operation with a detection range from 10 Gs to 400 Gs. The results indicate that the chip-integrated POF sensor is promising for magnetic field sensing.
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Dual-functioning multiple quantum well (MQW) diodes can simultaneously transmit and receive information through visible light. Here, we report vertically stacked red, green, and blue (RGB) MQW diodes for light detection and display applications. Both blue and green MQW diodes are monolithically integrated with distributed Bragg reflector (DBR) filters to realize the separation of light. The versatile RGB MQW transmitter/receiver system not only creates full-color display but also effectively separates RGB light into various colors. These results open feasible routes to generate multifunctional device for the development of full-color display and light receiver.
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III-nitride optoelectronic chips have tremendous potential for developing integrated computing and communication systems with low power consumption. The monolithic, top-down approaches are advantageous for simplifying the fabrication process and reducing the corresponding manufacturing cost. Herein, an ultraviolet optical interconnection system is investigated to discover the way of multiplexing between emission and absorption modulations on a monolithic optoelectronic chip. All on-chip components, the transmitter, monitor, waveguide, modulator, and receiver, share the same quantum well structure. As an example, two bias-controlled modulation modes are used to modulate video and audio signals in the experiment presented in this Letter. The results show that our on-chip optoelectronic system works efficiently in the near ultraviolet band, revealing the potential breadth of GaN optoelectronic integration.
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The combination of plastic optical fiber (POF) with monolithically integrated transmitter and receiver is becoming increasingly attractive for the development of miniature optoelectronic sensing systems. Here, we propose a temperature sensing system by integrating a GaN optoelectronic chip with a POF and aluminum (Al) reflector. Owing to the overlap between electroluminescence and responsivity spectra of multiple quantum well (MQW) diodes, both the transmitter and the receiver having identical MQW structures are monolithically integrated on a tiny GaN chip by using the same fabrication process flow. Environmental temperature change leads to thermal deformation in the Al reflector, which reflects the transmitted light back with a light pulse. The reflected light is coupled into the guided POF again and sensed by the on-chip receiver. Finally, the temperature information is read out as electrical signals. When the ambient temperature changes from 20.1°C to 100°C, the optically induced electrical signal decreases from -3.04 µA to -3.13 µA. The results suggest that the monolithically integrated GaN device offers a promising option for optoelectronic temperature sensing systems.
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BACKGROUND: Esophageal squamous cell carcinoma (ESCC) is a prevalent malignant tumor worldwide. Circular RNA (circRNA) is of great value in tumorigenesis progression. However, the mechanism of circFNDC3B in ESCC remains to be clarified. METHODS: Firstly, the circular characteristics of circFNDC3B were evaluated by Actinomycin D and RNase R measurements. The functions of circFNDC3B in ESCC cells were examined by CCK-8, EdU and flow cytometry. Subsequently, the molecular mechanism of circFNDC3B was explained using luciferase reporter gene detection. Finally, we constructed xenograft model to prove the role of circFNDC3B in vivo. RESULTS: Our study revealed that circFNDC3B was more stable than its linear RNA and prominently upregulated in ESCC. Functional findings suggested that silencing of circFNDC3B reduced the proliferation and enhanced apoptosis of ESCC cells in vitro. Meanwhile, knockdown of circFNDC3B attenuated tumor progression in vivo. Next, miR-370-3p/miR-136-5p was discovered to bind circFNDC3B. miR-370-3p/miR-136-5p reversed the promotive effect on cell proliferation and the inhibitory effect on cell apoptosis of circFNDC3B. MYO5A was a downstream target of miR-370-3p/miR-136-5p. CircFNDC3B served as a sponge for miR-370-3p/miR-136-5p and alleviated the prohibitory effect of miR-370-3p/miR-136-5p on MYO5A, which accelerated ESCC progression. CONCLUSION: circFNDC3B positively adjusted the MYO5A expression via spongy miR-370-3p/miR-136-5p, hence achieving the cancer-promoting effect on ESCC. circFNDC3B was a prospective diagnosis marker for ESCC.
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Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , MicroRNAs , Miosina Tipo V , RNA Circular , Humanos , Neoplasias Esofágicas/genética , Carcinoma de Células Escamosas do Esôfago/genética , Genes Reporter , MicroRNAs/genética , Cadeias Pesadas de Miosina , Estudos Prospectivos , RNA Circular/genéticaRESUMO
Recently, studies have highlighted the potential danger for soil organisms posed by film-derived microplastics (MPs). However, the majority of those does not accurately reflect the field conditions and the degree of MP contamination that can be found in actual settings. To fill the gap between laboratory and field scenarios, the polyethylene (PE) plastic film was made into PE-MPs and aged. Toxicity and molecular mechanisms of pristine PE-MPs (PMPs) and aged PE-MPs (AMPs) with the concentration at 500 mg/kg of dry weight were determined after 14 days of exposure by measuring the oxidative stress, osmoregulation pressure, gut microbiota, and metabolic responses in earthworms under environmentally relevant conditions. Our research showed that, when compared to PMPs (13.13 ± 1.99 items/g), AMPs accumulated more (16.19 ± 8.47 items/g), caused more severe tissue lesions, and caused a higher increase of cell membrane osmotic pressure in earthworms' intestines. Furthermore, the proportion of probiotic bacteria Lactobacillus johnsonii in the gut bacterial communities was 24.26%, 23.26%, and 12.96%, while the proportion of pathogenic bacteria of the phylum Verrucomicrobia was 2.28%, 4.79%, and 10.39% in the control and PMP- and AMP-exposed earthworms, indicating that the decrease in number of probiotic bacteria and the increase in number of pathogenic bacteria were more pronounced in the gut of AMP- rather than PMP-exposed earthworms. Metabolomic analysis showed that AMP exposure reduced earthworm energy metabolites. Consequently, the constant need for energy may result in protein catabolism, which raises levels of some amino acids, disturbs normal cell homeostasis, causes changes of cell membrane osmolarity, and destroys the cell structure. Our studies showed that aged MPs, with the same characteristics as those found in the environment, have greater toxicity than pristine MPs. The results of this study broaden our understanding of the toxicological effects of MPs on soil organisms under environmentally relevant conditions.
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Oligoquetos , Poluentes do Solo , Animais , Microplásticos/toxicidade , Plásticos/toxicidade , Oligoquetos/metabolismo , Solo/química , Poluentes do Solo/toxicidade , PolietilenoRESUMO
Enantioselective labeling of important bioactive molecules in complex biological environments by artificial receptors has drawn great interest. From both the slight difference of enantiomers' physicochemical properties and inherently complexity in living organism point of view, it is still a contemporary challenge for preparing practical chiral device that could be employed in the model animal due to diverse biological interference. Herein, we introduce γ-cyclodextrin onto graphene oxide for fabricating γ-cyclodextrin and graphene oxide assemblies, which provided an efficient nanoplatform for chiral labelling of D-phenylalanine with higher chiral discrimination ratio of KD/KL = 8.21. Significantly, the chiral fluorescence quenching effect of this γ-CD-GO nanoplatform for D-phenylalanine enantiomer in zebrafish was 7.0-fold higher than L-isomer, which exhibiting real promise for producing practical enantio-differentiating graphene-based systems in a complex biological sample.
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Grafite , gama-Ciclodextrinas , Animais , Fenilalanina/química , Grafite/química , Peixe-Zebra , EstereoisomerismoRESUMO
The demand for on-chip multifunctional optoelectronic systems is increasing in today's Internet of Things era. III-nitride quantum well diodes (QWDs) can transmit and receive information through visible light and can be used as both light-emitting diodes (LEDs) and photodetectors (PDs). Spectral emission-detection overlap gives the III-nitride QWD an intriguing capability to detect and modulate light emitted by itself. In this paper, the coexistence of light emission and detection in a III-nitride QWD is experimentally demonstrated, and a wireless video communication system through light is established. When approximately biasing and illuminating at the same time, the III-nitride QWD can achieve light emission and detection simultaneously. This work provides a foundation for the development of multifunctional III-nitride QWDs and the realization of device-to-device data communication.
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In this Letter, we report an effective monolithic integration of a metal oxide semiconductor field effect (MOSFET) phototransistor (PT) and a light-emitting diode (LED) on a GaN-on-Si LED epitaxial (epi) wafer. Avoiding additional growth or Si diffusion, the PT was directly fabricated on the LED epi layer, providing a cost-effective and facile method. As a driver, the PT could modulate both peak value of the light intensity and output current of the integrated LED. As an ultraviolet (UV) detector, our PT showed sufficient responsivity. It was found that the gate-voltage-dependent photocurrent-response of the device had a shorter response time, and a higher responsivity was obtained at a higher gate-voltage bias. The device demonstrated a switching effect that the photoinduced current from the PT drove the LED when the UV lamp was turned on, whereas the photoinduced current stopped driving upon powering off the UV lamp. The experiment proved that the integrated device working as a UV detector exhibited a fast response time and a longstanding stability. We anticipate that such an approach could have potential applications for UV light detection and visible light communication (VLC).
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Inland river basins include critical habitats and provide various ecosystem services in extremely arid lands. However, we know little about the distribution patterns of soil fungal communities in these river basins. We investigated the distribution patterns of soil fungal communities from the riparian oasis zone (ROZ) to the circumjacent desert zone (CDZ) at the lower reaches of the Heihe River. The results indicated that soil fungal communities were mainly dominated by the phyla Ascomycota and Basidiomycota across all samples. The dominant soil fungi taxa were significantly different between ROZ and CDZ habitats at both the phylum and genus levels. Fungal alpha diversity was mainly affected by spatial factors and plant functional traits, and Pearson correlation analysis revealed that fungal alpha diversity was more closely related to plant functional traits than soil properties. Furthermore, fungal community structure was best explained by spatial factors and plant attributes (including plant diversity and plant functional traits). Together, our findings provide new insights into the significance of spatial factors and plant attributes for predicting distributions of fungal communities in arid inland river basins, which will help us better understand the functions and services of these ecosystems.
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Micobioma , Solo , China , Ecossistema , Plantas , Rios , Microbiologia do SoloRESUMO
Due to the electro-optic property of InGaN multiple quantum wells, a III-nitride diode can provide light transmission, photo detection, and energy harvesting under different bias conditions. Made of III-nitride diodes arrayed in a single chip, the combination allows the diodes to transmit, detect, and harvest visible light at the same time. Here, we monolithically integrate a III-nitride transmitter, receiver, and energy harvester using a compatible foundry process. By adopting a bottom SiO2/TiO2 distributed Bragg reflector, we present a III-nitride diode with a peak external quantum efficiency of 50.65% at a forward voltage of 2.6 V for light emission, a power conversion efficiency of 6.68% for energy harvesting, and a peak external quantum efficiency of 50.9% at a wavelength of 388 nm for photon detection. The energy harvester generates electricity from ambient light to directly turn the transmitter on. By integrating a circuit, the electrical signals generated by the receiver pulse the emitted light to relay information. The multifunctioning system can continuously operate without an external power supply. Our work opens up a promising approach to develop multicomponent systems with new interactive functions and multitasking devices, due to III-nitride diode arrays that can simultaneously transmit, detect, and harvest light.
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Multiple-quantum well (MQW) III-nitride diodes can both emit and detect light. In particular, a III-nitride diode can absorb shorter-wavelength photons generated from another III-nitride diode that shares an identical MQW structure because of the spectral overlap between the emission and detection spectra of the III-nitride diode, which establishes a wireless visible light communication system using two identical III-nitride diodes. Moreover, a wireless light communication system using a modulating retro-reflector (MRR) enables asymmetric optical links, which forms a two-way optical link using a single transmitter and receiver. Here, in association with an MRR, we propose, fabricate, and characterize asymmetric optical links using monolithic III-nitride diodes, where one III-nitride diode functions as a transmitter to emit light, an MRR reflects light with the encoded information, another monolithically integrated III-nitride diode serves as a receiver to absorb the reflected light to convert optical signals into electrical ones, and the encoded information is finally decoded. Advanced monolithic III-nitride asymmetric optical links can be developed toward Internet of Things (IoT) deployment based on such multifunction devices.
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BACKGROUND: Aberrant DNA methylation is significantly associated with breast cancer. METHODS: In this study, we aimed to determine novel methylation biomarkers using a bioinformatics analysis approach that could have clinical value for breast cancer diagnosis and prognosis. Firstly, differentially methylated DNA patterns were detected in breast cancer samples by comparing publicly available datasets (GSE72245 and GSE88883). Methylation levels in 7 selected methylation biomarkers were also estimated using the online tool UALCAN. Next, we evaluated the diagnostic value of these selected biomarkers in two independent cohorts, as well as in two mixed cohorts, through ROC curve analysis. Finally, prognostic value of the selected methylation biomarkers was evaluated breast cancer by the Kaplan-Meier plot analysis. RESULTS: In this study, a total of 23 significant differentially methylated sites, corresponding to 9 different genes, were identified in breast cancer datasets. Among the 9 identified genes, ADCY4, CPXM1, DNM3, GNG4, MAST1, mir129-2, PRDM14, and ZNF177 were hypermethylated. Importantly, individual value of each selected methylation gene was greater than 0.9, whereas predictive value for all genes combined was 0.9998. We also found the AUC for the combined signature of 7 genes (ADCY4, CPXM1, DNM3, GNG4, MAST1, PRDM14, ZNF177) was 0.9998 [95% CI 0.9994-1], and the AUC for the combined signature of 3 genes (MAST1, PRDM14, and ZNF177) was 0.9991 [95% CI 0.9976-1]. Results from additional validation analyses showed that MAST1, PRDM14, and ZNF177 had high sensitivity, specificity, and accuracy for breast cancer diagnosis. Lastly, patient survival analysis revealed that high expression of ADCY4, CPXM1, DNM3, PRDM14, PRKCB, and ZNF177 were significantly associated with better overall survival. CONCLUSIONS: Methylation pattern of MAST1, PRDM14, and ZNF177 may represent new diagnostic biomarkers for breast cancer, while methylation of ADCY4, CPXM1, DNM3, PRDM14, PRKCB, and ZNF177 may hold prognostic potential for breast cancer.
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Neoplasias da Mama , Biomarcadores Tumorais/genética , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Metilação de DNA , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , PrognósticoRESUMO
WHAT IS KNOWN AND OBJECTIVE: Interstitial lung disease (ILD) is a rare but life-threatening adverse event (AE) that can be induced by trastuzumab in patients with breast cancer. ILD is a known AE associated with trastuzumab therapy, but it has other causes. We describe a case of ILD, which was induced by Epstein-Barr virus (EBV). CASE SUMMARY: A 76-year-old female patient with early-stage HER-2-positive breast cancer presented with ILD after 10 cycles of trastuzumab and paclitaxel. After excluding the possibility of trastuzumab-induced AE, Epstein-Barr virus (EBV) was thought to be a possible cause. Her symptoms resolved after ganciclovir therapy and did not recur following reintroduction of trastuzumab therapy. WHAT IS NEW AND CONCLUSION: Given the known association of ILD with trastuzumab therapy, it was tempting to assign causality to this drug. Our investigations and observed treatment response of our patient to ganciclovir suggest that EBV was the cause.