Scattering/Fluorescence Dual-Mode Imaging in MnO2-Coated Silicon Nanospheres for Cancer Cell Detection.

A tumor microenvironment (TME)-responsive nanoprobe composed of a fluorescent dye-decorated silicon (Si) nanosphere core and a thin MnO2 shell is proposed for simple and intelligent detection of cancer cells. The Si nanosphere core with diameters of 100-200 nm provides environment-independent Mie scattering imaging, while, simultaneously, the MnO2 shell provides the capability to switch the on/off state of the dye fluorescence reacted to the glutathione (GSH) and/or H2O2 levels in a cancer cell. Si-MnO2 core-shell nanosphere probes are fabricated in a solution-based process from crystalline Si nanosphere cores. The fluorescence switching under exposure to GSH is demonstrated, and the mechanism is discussed based on detailed optical characterizations including single-particle spectroscopy. Different types of human cells are incubated with the nanoprobes, and a proof of concept experiment is performed. From the combination of the robust scattering images and GSH- and H2O2-sensitive fluorescence images, the feasibility of cancer cell detection by the multimodal nanoprobes is demonstrated.

A redox switch allows binding of Fe(II) and Fe(III) ions in the cyanobacterial iron-binding protein FutA from Prochlorococcus.

The marine cyanobacterium Prochlorococcus is a main contributor to global photosynthesis, whilst being limited by iron availability. Cyanobacterial genomes generally encode two different types of FutA iron-binding proteins: periplasmic FutA2 ABC transporter subunits bind Fe(III), while cytosolic FutA1 binds Fe(II). Owing to their small size and their economized genome Prochlorococcus ecotypes typically possess a single futA gene. How the encoded FutA protein might bind different Fe oxidation states was previously unknown. Here, we use structural biology techniques at room temperature to probe the dynamic behavior of FutA. Neutron diffraction confirmed four negatively charged tyrosinates, that together with a neutral water molecule coordinate iron in trigonal bipyramidal geometry. Positioning of the positively charged Arg103 side chain in the second coordination shell yields an overall charge-neutral Fe(III) binding state in structures determined by neutron diffraction and serial femtosecond crystallography. Conventional rotation X-ray crystallography using a home source revealed X-ray-induced photoreduction of the iron center with observation of the Fe(II) binding state; here, an additional positioning of the Arg203 side chain in the second coordination shell maintained an overall charge neutral Fe(II) binding site. Dose series using serial synchrotron crystallography and an XFEL X-ray pump-probe approach capture the transition between Fe(III) and Fe(II) states, revealing how Arg203 operates as a switch to accommodate the different iron oxidation states. This switching ability of the Prochlorococcus FutA protein may reflect ecological adaptation by genome streamlining and loss of specialized FutA proteins.

Multifaceted Approach for Quantification and Enzymatic Activity of Iduronate-2-Sulfatase to Support Developing Gene Therapy for Hunter Syndrome.

Mucopolysaccharidosis type II, commonly called Hunter syndrome, is a rare X-linked recessive disease caused by the deficiency of the lysosomal enzyme iduronate-2-sulphatase (I2S). A deficiency of I2S causes an abnormal glycosaminoglycans accumulation in the body's cells. Although enzyme replacement therapy is the standard therapy, adeno-associated viruses (AAV)-based gene therapy could provide a single-dose solution to achieve a prolonged and constant enzyme level to improve patient's quality of life. Currently, there is no integrated regulatory guidance to describe the bioanalytical assay strategy to support gene therapy products. Herein, we describe the streamlined strategy to validate/qualify the transgene protein and its enzymatic activity assays. The method validation for the I2S quantification in serum and method qualification in tissues was performed to support the mouse GLP toxicological study. Standard curves for I2S quantification ranged from 2.00 to 50.0 µg/mL in serum and 6.25 to 400 ng/mL in the surrogate matrix. Acceptable precision, accuracy, and parallelism in the tissues were demonstrated. To assess the function of the transgene protein, fit-for-purpose method qualification for the I2S enzyme activity in serum was performed. The observed data indicated that the enzymatic activity in serum increased dose-dependently in the lower I2S concentration range. The highest I2S transgene protein was observed in the liver among tissue measured, and its expression level was maintained up to 91 days after the administration of rAAV8 with a codon-optimized human I2S. In conclusion, the multifaceted bioanalytical method for I2S and its enzymatic activity were established to assess gene therapy products in Hunter syndrome.

Fluorophore-Decorated Mie Resonant Silicon Nanosphere for Scattering/Fluorescence Dual-Mode Imaging.

Inorganic nanoparticles with multiple functions have been attracting attention as multimodal nanoprobes in bioimaging, biomolecule detection, and medical diagnosis and treatment. A drawback of conventional metallic nanoparticle-based nanoprobes is the Ohmic losses that lead to fluorescence quenching of attached molecules and local heating under light irradiation. Here, metal-free nanoprobes capable of scattering/fluorescence dual-mode imaging are developed. The nanoprobes are composed of a silicon nanosphere core having efficient Mie scattering in the visible to near infrared range and a fluorophore doped silica shell. The dark-field scattering and photoluminescence images/spectra for nanoprobes made from different size silicon nanospheres and different kinds of fluorophores are studied by single particle spectroscopy. The fluorescence spectra are strongly modified by the Mie modes of a silicon nanosphere core. By comparing scattering and fluorescence spectra and calculated Purcell factors, the fluorescence enhancement factor is quantitatively discussed. In vitro scattering/fluorescence imaging studies on human cancer cells demonstrate that the developed nanoparticles work as scattering/fluorescence dual-mode imaging nanoprobes.

Complications of a lung biopsy for severe respiratory failure: A systematic review and meta-analysis.

BACKGROUND: This systematic review and meta-analysis aimed to evaluate the complications of lung biopsy in patients with acute respiratory failure (ARF), including acute respiratory distress syndrome (ARDS). METHODS: We searched the MEDLINE and Cochrane Central Register of Controlled Trials. The primary outcomes were biopsy-related death, respiratory failure, cardiac complications, bleeding, and other major complications. We used the McMaster Quality Assessment Scale of Harms (McHarm) to evaluate the risk of bias. A random-effects model was used to calculate the pooled frequencies. RESULTS: Thirteen studies (consisting of 574 patients) were included in the meta-analysis. Furthermore, most of the included studies had a high or unclear risk of bias in half of the items in McHarm. All included studies evaluated surgical lung biopsies. The median overall hospital mortality was 53% (range: 17%-90%). The pooled frequencies of biopsy-related death, respiratory failure, cardiac complication, bleeding, and other major complications were 0.00% (95% confidence interval [CI]: 0.00%-0.21%), 1.30% (95% CI: 0.00%-5.69%), 1.03% (95% CI: 0.00%-3.73%), 1.46% (95% CI: 0.16%-3.56%), and 4.26% (95% CI: 0.00%-13.0%), respectively. CONCLUSIONS: The results of this study will be valuable information in considering the indications of lung biopsy in patients with ARF, including ARDS. TRIAL REGISTRATION: The protocol was registered with the University Hospital Medical Information Network Clinical Trials Registry (UMIN 000040650).

Re-expansion pulmonary edema after chest tube drainage of malignant pleural effusion.

A 62-year-old man presented with a 3-day history of dyspnea. Chest X-ray revealed a pleural effusion. We performed chest tube drainage, and then the patient experienced re-expansion pulmonary edema. His respiratory distress improved after the treatment of noninvasive positive pressure ventilation and intravenous methylprednisolone.

Disentangling Cathodoluminescence Spectra in Nanophotonics: Particle Eigenmodes vs Transition Radiation.

Cathodoluminescence spectroscopy performed in an electron microscope has proven a versatile tool for analyzing the near- and far-field optical response of plasmonic and dielectric nanostructures. Nevertheless, the transition radiation produced by electron impact is often disregarded in the interpretation of the spectra recorded from resonant nanoparticles. Here we show, experimentally and theoretically, that transition radiation can by itself generate distinct resonances that, depending on the time-of-flight of the electron beam inside the particle, can result from constructive or destructive interference in time. Superimposed on the eigenmodes of the investigated structures, these resonances can distort the recorded spectrum and lead to potentially erroneous assignment of modal characters to the spectral features. We develop an intuitive analogy that helps distinguish between the two contributions. As an example, we focus on the case of silicon nanospheres and show that our analysis facilitates the unambiguous interpretation of experimental measurements on Mie-resonant nanoparticles.

Elevated serum creatine kinase levels due to osimertinib: A case report and review of the literature.

INTRODUCTION: Osimertinib is a tyrosine kinase inhibitor that targets the epidermal growth factor receptor. Elevated serum creatine kinase level is an uncommon adverse event associated with osimertinib treatment for lung cancer. CASE REPORT: We report a previously healthy 56-year-old woman who developed elevated serum creatine kinase levels during osimertinib monotherapy for epidermal growth factor receptor mutation-positive lung adenocarcinoma. MANAGEMENT & OUTCOME: During treatment, she experienced leg cramps and her serum creatine kinase levels increased, peaking at 989 U/l. Further investigation revealed no evidence of cardiotoxicity or myositis; thus, osimertinib-induced myopathy was assumed to be the cause of her elevated serum creatine kinase levels. We successfully managed both lung cancer and osimertinib-induced myopathy using 1-week pauses of osimertinib therapy without dose reduction. DISCUSSION: Short-term suspension of osimertinib without dose reduction may be a reasonable option for osimertinib-induced myopathy.

Clinically amyopathic dermatomyositis during the COVID-19 pandemic.

An 84-year-old Japanese woman presented to our hospital with a month-long dry cough during the coronavirus disease 2019 (COVID-19) pandemic. She also had skin lesions on her fingers from 3 months prior. A chest computed tomography (CT) scan showed bilateral ground- glass opacities with a subpleural distribution, similar to the findings of COVID-19. The results of COVID-19 tests were negative. The titer of the anti-melanoma differentiation-associated gene 5 (MDA5) antibody was elevated. Consequently, we confirmed the diagnosis of clinically amyopathic dermatomyositis (CADM) and then administered oral prednisolone combined with tacrolimus. After the treatment, her symptoms, skin lesions and CT findings were gradually resolved.

Targeted Mass Spectrometry-Based Approach for the Determination of Intrinsic Internalization Kinetics of Cell-Surface Membrane Protein Targets.

Successful development of targeted therapeutics aimed at the elimination of diseased cells relies on the target properties and the therapeutics that target them. Currently, target properties have been evaluated through antibody-dependent semiquantitative approaches such as flow cytometry, Western blotting, or microscopy. Since antibodies can alter target properties following binding, antibody-dependent approaches provide at best skewed measurements for target intrinsic properties. To circumvent, here we attempted to develop an antibody-free targeted mass spectrometry-based (ATM) strategy to measure the surface densities and the intrinsic rates (Kint) of CD38 internalization in multiple myeloma cell lines. Using cell-surface biotinylation in conjunction with differential mass tagging to separate inward CD38 molecules from the outbound and nascent ones, the ATM approach revealed diversities in measured CD38 Kint values of 0.239 min-1 S.E. ± 0.076, 0.109 min-1 S.E. ± 0.032, and 0.058 min-1 S.E. ± 0.001 for LP1, NCIH929, and MOLP8 cell lines, respectively. Together with CD38 surface densities, intrinsic Kint values aligned well with the tumor penetration model and supported the outcomes for tumor regression in mouse xenografts upon drug treatment. Additionally, the ATM approach can evaluate molecules with fast Kint as we determined for CTLA4 protein. We believe that the ATM approach has the potential to evaluate diverse cell-surface targets as part of the pharmacological assessment in drug discovery.

Invasive Mucinous Adenocarcinoma of the Lung Presenting With Multiple Cavities.

A 78-year-old woman presented to our hospital with a two-week history of productive cough. Chest computed tomography (CT) showed bilateral multiple pulmonary nodules with cavities. Although the cytology of her sputum revealed adenocarcinoma, she refused any treatment. Following supportive care, 30 months later, she presented to our hospital with dyspnea and fever. Chest CT showed progression of multiple pulmonary nodules and cavities. Despite treatment with antibiotics and palliative care, she died on the 10th day of hospitalization. Pathological autopsy confirmed the diagnosis of pulmonary invasive mucinous adenocarcinoma (IMA). The typical CT findings of IMA include multiple consolidations or ground-glass opacities mimicking pneumonia; rarely, cavitary lesions are also observed. Clinicians should consider IMA as a differential diagnosis for lung cavities.

Optimizing plasmon enhanced luminescence in silicon nanocrystals by gold nanorods.

The great application potential of photoluminescent silicon nanocrystals, especially in biomedicine, is significantly reduced due to their limited radiative rate. One of the possible ways to overcome this limitation is enhancing the luminescence by localized plasmons of metallic nanostructures. We report an optimized fabrication of gold nanorod - silicon nanocrystal core-shell nanoparticles with the silica shell as a tunable spacer. The unprecedented structural quality and homogeneity of our hybrid nanoparticles allows for detailed analysis of their luminescence. A strong correlation between dark field scattering and luminescence spectra is shown on a single particle level, indicating a dominant role of the longitudinal plasmonic band in luminescence enhancement. The spacer thickness dependence of photoluminescence intensity enhancement is investigated using a combination of experimental measurements and numerical simulations. An optimal separation distance of 5 nm is found, yielding a 7.2× enhancement of the luminescence intensity. This result is mainly attributed to an increased quantum yield resulting from the Purcell enhanced radiative rate in the nanocrystals. The ease of fabrication, low cost, long-term stability and great emission properties of the hybrid nanoparticles make them a great candidate for bio-imaging or even targeted cancer treatment.

Insights on Droplet Digital PCR-Based Cellular Kinetics and Biodistribution Assay Support for CAR-T Cell Therapy.

Characterizing in vivo cellular kinetics and biodistribution of chimeric antigen receptor T (CAR-T) cells is critical for toxicity assessment, nonclinical and clinical efficacy studies. To date, the standardized assay to characterize CAR-T cell distribution, expansion, contraction, and persistence profiles is not readily available. To overcome this limitation and increase comparability among studies, we have established a universal protocol for analysis. We established a duplexing ddPCR protocol for the CAR-T transgene and reference gene to normalize the genomic DNA input prepared from mouse blood and tissues. The high-throughput gDNA extraction method enabled highly reproducible gDNA extraction while eliminating labor-intensive steps. The investigational CAR-T cells were intravenously injected into immunodeficient mice bearing human colorectal cancer xenografts. The blood and tissue samples were collected to measure the cellular kinetics by ddPCR and flow cytometry. The standard curves were linear throughout the calibration range with acceptable intra- and inter-day precision and accuracy. The gDNA recovery study performed by spiking in the exo-gene plasmid DNA or CAR-T cells revealed that the recovery ranged from 60 to 100% in blood and tissue homogenates. The use of both units of copy/µg gDNA and copy/µL blood met the current regulatory requirement and allowed for a systematic understanding of CAR-T cell expansion and a direct comparison with the flow cytometry data. A standardized ddPCR assay, including automated gDNA extraction procedures, has been established for evaluating cellular kinetics and biodistribution in CAR-T cell therapies.

Safety and feasibility of lung biopsy in diagnosis of acute respiratory distress syndrome: protocol for a systematic review and meta-analysis.

INTRODUCTION: Acute respiratory distress syndrome (ARDS) is a type of acute respiratory failure characterised by non-cardiac pulmonary oedema caused by various underlying conditions. ARDS is often pathologically characterised by diffuse alveolar damage, and its pathological findings have been reported to be associated with prognosis, although the adverse effects of lung biopsies to obtain pathological findings are still unclear. The purpose of this systematic review and meta-analysis is to reveal the safety and feasibility of lung biopsy in the diagnosis of ARDS. METHODS AND ANALYSIS: We will include studies that were published in MEDLINE and Cochrane Central Register of Controlled Trials until 1 June 2020. We will include the reports for critically ill patients in an intensive care unit or emergency department who undergo lung biopsy and require a mechanical ventilation. Two review authors will independently scan titles and abstracts of all identified studies. Furthermore, these two authors will read and assess the full text of study reports to identify trials that appeared broadly to address the subject of the review. We will perform a risk of bias assessment using the McMaster Quality Assessment Scale of Harms. ETHICS AND DISSEMINATION: This study will be based on the published data, therefore, it does not require ethical approval. The final results of the study will be published in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: UMIN000040650.

Pulmonary lymphangitic carcinomatosis secondary to ureteral cancer.

BACKGROUND: Pulmonary lymphangitic carcinomatosis (PLC) is a metastatic lung disease of malignant tumors that spread through pulmonary lymphatic vessels. Although prompt diagnosis and specific treatment of PLC are required due to the poor prognosis associated with this disease, it is often challenging to determine the primary cancer site. CASE PRESENTATION: A 67-year-old Japanese woman presented to our hospital with a 10-day history of cough and dyspnea on exertion. Chest radiography and computed tomography (CT) revealed diffuse nodular opacities with interlobular septal thickening. Both bronchoalveolar lavage (BAL) and transbronchial lung biopsy (TBLB) revealed carcinoma cells with unknown origin. Contrast-enhanced CT depicted a mass in the right ureter with hydronephrosis, and retrograde urography showed a narrowing of the right ureter. Urine cytology from her right ureter via ureteral catheter also revealed atypical cells, highly suggestive of malignancy. Immunohistochemical examination of lung specimens via TBLB showed results consistent with lung metastasis of ureteral cancer. Therefore, we arrived at a diagnosis of PLC secondary to ureteral cancer. CONCLUSIONS: This case encouraged multidisciplinary discussion and a whole-body examination, including TBLB with immunohistochemistry, to determine the origin of PLC.

Black bronchoscopy in a patient with pulmonary malignant melanoma: A case report.

A 47-year-old Japanese man was referred to our hospital with a one-week history of chest discomfort. Chest computed tomography (CT) revealed a mass in the right upper lobe suspected to be primary lung cancer. A biopsy of the mass using endobronchial ultrasonography (EBUS) with guide sheath (GS) was performed, and a black-colored mass was observed which occluded almost all of the right B2 b bronchus. Immunohistochemistry of lung specimens was compatible with a diagnosis of malignant melanoma which was confirmed to be BRAF wild-type. Furthermore, positron emission tomography (PET) and contrast-enhanced magnetic resonance imaging (MRI) of the head revealed multiple metastatic lesions in the brain, liver, and bones. The patient was referred to another hospital for specific treatment. After that, the patient's melanoma was confirmed to have the BRAF wild-type gene and PD-L1 expression was 80%. Then, combined therapy of nivolumab plus ipilimumab was subsequently administered.

Discovery of a Novel, Highly Potent, and Selective Thieno[3,2-d]pyrimidinone-Based Cdc7 Inhibitor with a Quinuclidine Moiety (TAK-931) as an Orally Active Investigational Antitumor Agent.

In our pursuit of developing a novel, potent, and selective cell division cycle 7 (Cdc7) inhibitor, we optimized the previously reported thieno[3,2-d]pyrimidinone analogue I showing time-dependent Cdc7 kinase inhibition and slow dissociation kinetics. These medicinal chemistry efforts led to the identification of compound 3d, which exhibited potent cellular activity, excellent kinase selectivity, and antitumor efficacy in a COLO205 xenograft mouse model. However, the issue of formaldehyde adduct formation emerged during a detailed study of 3d, which was deemed an obstacle to further development. A structure-based approach to circumvent the adduct formation culminated in the discovery of compound 11b (TAK-931) possessing a quinuclidine moiety as a preclinical candidate. In this paper, the design, synthesis, and biological evaluation of this series of compounds will be presented.