Injectable Mechanophore Nanoparticles for Deep-Tissue Mechanochemical Dynamic Therapy.

Photodynamic therapy (PDT) and sonodynamic therapy (SDT), using nonionizing light and ultrasound to generate reactive oxygen species, offer promising localized treatments for cancers. However, the effectiveness of PDT is hampered by inadequate tissue penetration, and SDT largely relies on pyrolysis and sonoluminescence, which may cause tissue injury and imprecise targeting. To address these issues, we have proposed a mechanochemical dynamic therapy (MDT) that uses free radicals generated from mechanophore-embedded polymers under mechanical stress to produce reactive oxygen species for cancer treatment. Yet, their application in vivo is constrained by the bulk form of the polymer and the need for high ultrasound intensities for activation. In this study, we developed injectable, nanoscale mechanophore particles with enhanced ultrasound sensitivity by leveraging a core-shell structure comprising silica nanoparticles (NPs) whose interfaces are linked to polymer brushes by an azo mechanophore moiety. Upon focused ultrasound (FUS) treatment, this injectable NP generates reactive oxygen species (ROS), demonstrating promising results in both an in vitro 4T1 cell model and an in vivo mouse model of orthotopic breast cancers. This research offers an alternative therapy technique, integrating force-responsive azo mechanophores and FUS under biocompatible conditions.

Biomimetic-Membrane-Protected Plasmonic Nanostructures as Dual-Modality Contrast Agents for Correlated Surface-Enhanced Raman Scattering and Photoacoustic Detection of Hidden Tumor Lesions.

Optical imaging and spectroscopic modalities are of considerable current interest for in vivo cancer detection and image-guided surgery, but the turbid or scattering nature of biomedical tissues has severely limited their abilities to detect buried or occluded tumor lesions. Here we report the development of a dual-modality plasmonic nanostructure based on colloidal gold nanostars (AuNSs) for simultaneous surface-enhanced Raman scattering (SERS) and photoacoustic (PA) detection of tumor phantoms embedded (hidden) in ex vivo animal tissues. By using red blood cell membranes as a naturally derived biomimetic coating, we show that this class of dual-modality contrast agents can provide both Raman spectroscopic and PA signals for the detection and differentiation of hidden solid tumors with greatly improved depths of tissue penetration. Compared to previous polymer-coated AuNSs, the biomimetic coatings are also able to minimize protein adsorption and cellular uptake when exposed to human plasma without compromising their SERS or PA signals. We further show that tumor-targeting peptides (such as cyclic RGD) can be noncovalently inserted for targeting the ανß3-integrin receptors expressed on metastatic cancer cells and tracked via both SERS and PA imaging (PAI). Finally, we demonstrate image-guided resections of tumor-mimicking phantoms comprising metastatic tumor cells buried under layers of skin and fat tissues (6 mm in thickness). Specifically, PAI was used to determine the precise tumor location, while SERS spectroscopic signals were used for tumor identification and differentiation. This work opens the possibility of using these biomimetic dual-modality nanoparticles with superior signal and biological stability for intraoperative cancer detection and resection.

Visualizing ultrafast photothermal dynamics with decoupled optical force nanoscopy.

The photothermal effect in nanomaterials, resulting from resonant optical absorption, finds wide applications in biomedicine, cancer therapy, and microscopy. Despite its prevalence, the photothermal effect in light-absorbing nanoparticles has typically been assessed using bulk measurements, neglecting near-field effects. Beyond standard imaging and therapeutic uses, nanosecond-transient photothermal effects have been harnessed for bacterial inactivation, neural stimulation, drug delivery, and chemical synthesis. While scanning probe microscopy and electron microscopy offer single-particle imaging of photothermal fields, their slow speed limits observations to milliseconds or seconds, preventing nanoscale dynamic investigations. Here, we introduce decoupled optical force nanoscopy (Dofn), enabling nanometer-scale mapping of photothermal forces by exploiting unique phase responses to temporal modulation. We employ the photothermal effect's back-action to distinguish various time frames within a modulation period. This allows us to capture the dynamic photothermal process of a single gold nanorod in the nanosecond range, providing insights into non-stationary thermal diffusion at the nanoscale.

[Risk factors for hemorrhagic cystitis in children with ß-thalassemia major after allogeneic hematopoietic stem cell transplantation]. / 重型ßåœ°ä¸­æµ·è´«è¡€å„¿ç«¥å¼‚åŸºå› é€ è¡€å¹²ç»†èƒžç§»æ¤åŽå¹¶å‘å‡ºè¡€æ€§è†€èƒ±ç‚Žçš„å±é™©å› ç´ åˆ†æž.

OBJECTIVES: To explore the risk factors for hemorrhagic cystitis (HC) in children with ß-thalassemia major (TM) undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT). METHODS: A retrospective analysis was conducted on clinical data of 247 children with TM who underwent allo-HSCT at Shenzhen Children's Hospital from January 2021 to November 2022. The children were divided into an HC group (91 cases) and a non-HC group (156 cases) based on whether HC occurred after operation. Multivariable logistic regression analysis was used to explore the risk factors for HC, and the receiver operating characteristic curve was used to analyze the predictive efficacy of related factors for HC. RESULTS: Among the 247 TM patients who underwent allo-HSCT, the incidence of HC was 36.8% (91/247). Univariate analysis showed age, incompatible blood types between donors and recipients, occurrence of acute graft-versus-host disease (aGVHD), positive urine BK virus deoxyribonucleic acid (BKV-DNA), and ≥2 viral infections were associated with the development of HC after allo-HSCT (P<0.05). Multivariable analysis revealed that incompatible blood types between donors and recipients (OR=3.171, 95%CI: 1.538-6.539), occurrence of aGVHD (OR=2.581, 95%CI: 1.125-5.918), and positive urine BKV-DNA (OR=21.878, 95%CI: 9.633-49.687) were independent risk factors for HC in children with TM who underwent allo-HSCT. The receiver operating characteristic curve analysis showed that positive urine BKV-DNA alone or in combination with two other risk factors (occurrence of aGVHD, incompatible blood types between donors and recipients) had a certain accuracy in predicting the development of HC after allo-HSCT (area under the curve >0.8, P<0.05). CONCLUSIONS: Incompatible blood types between donors and recipients, occurrence of aGVHD, and positive urine BKV-DNA are risk factors for HC after allo-HSCT in children with TM. Regular monitoring of urine BKV-DNA has a positive significance for early diagnosis and treatment of HC.

Detecting rare thalassemia in children with anemia using third-generation sequencing.

BACKGROUND: In China, conventional genetic testing methods can only detect common thalassemia variants. Accurate detection of rare thalassemia is crucial for clinical diagnosis, especially for children that need long-term blood transfusion. This study aims to explore the application value of third-generation sequencing (TGS) in the diagnosis of rare thalassemia in children with anemia. METHODS: We enrolled 20 children with anemia, excluding from iron deficiency anemia (IDA). TGS was employed to identify both known and novel thalassemia genotypes, while sanger sequencing was used to confirm the novel mutation detected. RESULTS: Among the 20 samples, we identified 5 cases of rare thalassemia. These included ß-4.9 (hg38,Chr11:5226187-5231089) at HBB gene, α-91(HBA2:c.*91delT), αCD30(HBA2:c.91-93delGAG), Chinese Gγ+(Aγδß)0(NG_000007.3: g .48795-127698 del 78904) and delta - 77(T > C)(HBD:c.-127T>C). Notably, the -SEA/α-91α genotype associated with severe non-deletional hemoglobin H disease (HbH disease) has not been previously reported. Patients with genotypes ß654/ß-4.9 and -SEA/α-91α necessitate long-term blood transfusions, and those with the -SEA/αCD30α, Chinese Gγ+(Aγδß)0 and delta thalassemia demonstrate mild anemia. CONCLUSIONS: TGS demonstrates promising potential as a diagnostic tool for suspected cases of rare thalassemia in children, especially those suspected to have transfusion-dependent thalassemia (TDT).

Hybrid photoacoustic and fast super-resolution ultrasound imaging.

The combination of photoacoustic (PA) imaging and ultrasound localization microscopy (ULM) with microbubbles has great potential in various fields such as oncology, neuroscience, nephrology, and immunology. Here we developed an interleaved PA/fast ULM imaging technique that enables super-resolution vascular and physiological imaging in less than 2 seconds per frame in vivo. By using sparsity-constrained (SC) optimization, we accelerated the frame rate of ULM up to 37 times with synthetic data and 28 times with in vivo data. This allows for the development of a 3D dual imaging sequence with a commonly used linear array imaging system, without the need for complicated motion correction. Using the dual imaging scheme, we demonstrated two in vivo scenarios challenging to image with either technique alone: the visualization of a dye-labeled mouse lymph node showing nearby microvasculature, and a mouse kidney microangiography with tissue oxygenation. This technique offers a powerful tool for mapping tissue physiological conditions and tracking the contrast agent biodistribution non-invasively.

Photoacoustic signal enhancement in dual-contrast gastrin-releasing peptide receptor-targeted nanobubbles.

Translatable imaging agents are a crucial element of successful molecular imaging. Photoacoustic molecular imaging relies on optical absorbing materials to generate a sufficient signal. However, few materials approved for human use can generate adequate photoacoustic responses. Here we report a new nanoengineering approach to further improve photoacoustic response from biocompatible materials. Our study shows that when optical absorbers are incorporated into the shell of a gaseous nanobubble, their photoacoustic signal can be significantly enhanced compared to the original form. As an example, we constructed nanobubbles using biocompatible indocyanine green (ICG) and biodegradable poly(lactic-co-glycolic acid) (PLGA). We demonstrated that these ICG nanobubbles generate a strong ultrasound signal and almost four-fold photoacoustic signal compared to the same concentration of ICG solution; our theoretical calculations corroborate this effect and elucidate the origin of the photoacoustic enhancement. To demonstrate their molecular imaging performance, we conjugated gastrin-releasing peptide receptor (GRPR) targeting ligands with the ICG nanobubbles. Our dual photoacoustic/ultrasound molecular imaging shows a more than three-fold enhancement in targeting specificity of the GRPR-targeted ICG nanobubbles, compared to untargeted nanobubbles or prostate cancer cells not expressing GRPR, in a prostate cancer xenograft mouse model in vivo.

Understanding the near-field photoacoustic spatiotemporal profile from nanostructures.

Understanding the mechanism of photoacoustic generation at the nanoscale is key to developing more efficient photoacoustic devices and agents. Unlike the far-field photoacoustic effect that has been well employed in imaging, the near-field profile leads to a complex wave-tissue interaction but is understudied. Here we show that the spatiotemporal profile of the near-field photoacoustic waves can be shaped by laser pulses, anisotropy, and the spatial arrangement of nanostructure(s). Using a gold nanorod as an example, we discovered that the near-field photoacoustic amplitude in the short axis is ∼75 % stronger than the long axis, and the anisotropic spatial distribution converges to an isotropic spherical wave at ∼50 nm away from the nanorod's surface. We further extend the model to asymmetric gold nanostructures by arranging isotropic nanoparticles anisotropically with broken symmetry to achieve a precisely controlled near-field photoacoustic "focus" largely within an acoustic wavelength.

A crosstalk of circadian clock and alternative splicing under abiotic stresses in the plants.

The circadian clock is an internal time-keeping mechanism that synchronizes the physiological adaptation of an organism to its surroundings based on day and night transition in a period of 24 h, suggesting the circadian clock provides fitness by adjusting environmental constrains. The circadian clock is driven by positive and negative elements that regulate transcriptionally and post-transcriptionally. Alternative splicing (AS) is a crucial transcriptional regulator capable of generating large numbers of mRNA transcripts from limited numbers of genes, leading to proteome diversity, which is involved in circadian to deal with abiotic stresses. Over the past decade, AS and circadian control have been suggested to coordinately regulate plant performance under fluctuating environmental conditions. However, only a few reports have reported the regulatory mechanism of this complex crosstalk. Based on the emerging evidence, this review elaborates on the existing links between circadian and AS in response to abiotic stresses, suggesting an uncovered regulatory network among circadian, AS, and abiotic stresses. Therefore, the rhythmically expressed splicing factors and core clock oscillators fill the role of temporal regulators participating in improving plant growth, development, and increasing plant tolerance against abiotic stresses.

Genome-wide comparison and in silico analysis of splicing factor SYF2/NTC31/p29 in eukaryotes: Special focus on vertebrates.

The gene SYF2-an RNA splicing factor-can interact with Cyclin D-type binding protein 1 (GICP) in many biological processes, including splicing regulation, cell cycle regulation, and DNA damage repair. In our previous study we performed genome-wide identification and functional analysis of SYF2 in plant species. The phylogenetic relationships and expression profiles of SYF2 have not been systematically studied in animals, however. To this end, the gene structure, genes, and protein conserved motifs of 102 SYF2 homologous genes from 91 different animal species were systematically analyzed, along with conserved splicing sites in 45 representative vertebrate species. A differential comparative analysis of expression patterns in humans and mice was made. Molecular bioinformatics analysis of SYF2 showed the gene was conserved and functional in different animal species. In addition, expression pattern analysis found that SYF2 was highly expressed in hematopoietic stem cells, T cells, and lymphoid progenitor cells; in ovary, lung, and spleen; and in other cells and organs. This suggests that changes in SYF2 expression may be associated with disease development in these cells, tissues, or organs. In conclusion, our study analyzes the SYF2 disease resistance genes of different animal species through bioinformatics, reveals the relationship between the SYF2 genotype and the occurrence of certain diseases, and provides a theoretical basis for follow-up study of the relationship between the SYF2 gene and animal diseases.

Identification of a Novel Hb H Disease with Glucose-6-Phosphate Dehydrogenase Deficiency Using Whole Genome Sequencing.

With the development of sequencing technology, more and more rare thalassemia types have been found. In this article, we found a novel Hb H disease combined with glucose-6-phosphate dehydrogenase (G6PD) deficiency through whole genome sequencing (WGS), which was verified by Sanger sequencing and polymerase chain reaction (PCR)-reverse dot-blot hybridization, respectively.

Invasive Salmonella Infections Among Children in Shenzhen, China: A Five-year Retrospective Review.

BACKGROUND: Invasive Salmonella infections are highly prevalent worldwide. Clinical data of childhood invasive Salmonella infections from China are limited. METHODS: Data of hospitalized children <18 years old with invasive Salmonella infections from 2016 to 2020 in Shenzhen Children's Hospital in Shenzhen were retrospectively collected. Serotypes and antimicrobial susceptibility tests of the invasive Salmonella isolates were performed. RESULTS: Sixty-three cases were enrolled during the 5-year study period including 8 in 2016, 11 in 2017, 16 in 2018, 6 in 2019 and 22 in 2020. The median age was 15 months (interquartile range, 11-22 months), and 79.4% (50 cases) were <2 years of age. Underlying diseases were found in 28.6% (18 cases) of the patients with a great variety, but no cases of malaria or HIV infection were identified. Most of the invasive Salmonella cases were bloodstream infections (84.1%), followed by osteoarthritis (11.1%) and meningitis (4.8%). Gastroenteritis (49.2%) and pneumonia (28.6%) were found to be the major manifestations among the patients. Furthermore, invasive Salmonella infections resulted in the death of 3 children (4.8%). Salmonella enteritis (12 cases; 15.9%) and Salmonella typhimurium (9 cases; 19.0%) as the most common serovars were identified. The resistance rates of Salmonella strains to ceftriaxone, ceftazidime and cefepime were also measured to be 17.5%, 17.5% and 9.5%, respectively. CONCLUSIONS: An increasing number of childhood invasive Salmonella infections with a broad range of serotypes was observed in Shenzhen, China. It is critical to pay attention to the antimicrobial resistance of the isolates taken from children with invasive Salmonella infections.

[Prognostic Factors Analysis of Children with Hemophagocytic Lymphohistiocytosis].

OBJECTIVE: To analyze the risk factors affecting prognosis of children with hemophagocytic lymphohistiocytosis (HLH). METHODS: The clinical manifestations and laboratory data of 143 HLH children who met the HLH-2004 diagnostic criteria in Shenzhen Children's Hospital from January 2009 to May 2017 were retrospectively analyzed, and the independent factors affecting prognosis were also analyzed. RESULTS: The median age of 143 HLH children was 1.9 (0.1-14.3) years old, and the median follow-up time was 6.7 years (1 day - 11.9 years). The overall survival rate of 1 month, 1 year, and 10 years was (87.4±5.5)%, (81.1±6.5)%, and (81.1±6.5)%, respectively. The deaths occurred within 1 year after onset. Multivariate analysis showed that central nervous system (CNS) involvement (P=0.047), low hemoglobin (P=0.002), prolonged activated partial thromboplastin time (APTT) (P<0.001), high triglyceride (P=0.005) were all the independent risk factors affecting survival of the children. Receiver operating characteristic curve indicated that APTT (AUC=0.753, P<0.001) was more valuable than other risk factors in predicting death of the children. The cut-off value of APTT was 56.6 s, and the sensitivity and specificity of which was 55.6% and 89.7%, respectively. CONCLUSION: Hypohemoglobinemia, prolonged APTT, hypertriglyceridemia, and CNS involvement the risk factors affecting prognosis of HLH, and prolonged APTT shows a strong predictive value for death.

Quantifying molecular- to cellular-level forces in living cells.

Mechanical cues have been suggested to play an important role in cell functions and cell fate determination, however, such physical quantities are challenging to directly measure in living cells with single molecule sensitivity and resolution. In this review, we focus on two main technologies that are promising in probing forces at the single molecule level. We review their theoretical fundamentals, recent technical advancements, and future directions, tailored specifically for interrogating mechanosensitive molecules in live cells.

Ultra-high-frequency radio-frequency acoustic molecular imaging with saline nanodroplets in living subjects.

Molecular imaging is a crucial technique in clinical diagnostics but it relies on radioactive tracers or strong magnetic fields that are unsuitable for many patients, particularly infants and pregnant women. Ultra-high-frequency radio-frequency acoustic (UHF-RF-acoustic) imaging using non-ionizing RF pulses allows deep-tissue imaging with sub-millimetre spatial resolution. However, lack of biocompatible and targetable contrast agents has prevented the successful in vivo application of UHF-RF-acoustic imaging. Here we report our development of targetable nanodroplets for UHF-RF-acoustic molecular imaging of cancers. We synthesize all-liquid nanodroplets containing hypertonic saline that are stable for at least 2 weeks and can produce high-intensity UHF-RF-acoustic signals. Compared with concentration-matched iron oxide nanoparticles, our nanodroplets produce at least 1,600 times higher UHF-RF-acoustic signals at the same imaging depth. We demonstrate in vivo imaging using the targeted nanodroplets in a prostate cancer xenograft mouse model expressing gastrin release protein receptor (GRPR), and show that targeting specificity is increased by more than 2-fold compared with untargeted nanodroplets or prostate cancer cells not expressing this receptor.

A Wearable Metasurface for High Efficiency, Free-Positioning Omnidirectional Wireless Power Transfer.

We introduce a design principle of metasurfaces that can form any desired distribution of magnetic field for high-efficiency wireless power transfer centered at 200 kHz, which can be used to efficiently charge implanted medical devices. This metasurface can improve the power transfer efficiency for both single-user and multi-user cases by over tenfold compared to those without the metasurface. Our design enables a robust field distribution to the positions of the transmitting and receiving coils, as well as the geometric distortions of the metasurface itself, demonstrating feasibilities as a wearable device. With our design, the field distribution and subsequent power division among the multiple users can be readily controlled from equal distribution to any selective user(s). When incorporating a three-dimensional unit cell of the metasurface, we theoretically demonstrate an omnidirectional control of the field orientation to achieve a high-efficiency wireless power transfer for multiple users.

Mitochondrial copper depletion suppresses triple-negative breast cancer in mice.

Depletion of mitochondrial copper, which shifts metabolism from respiration to glycolysis and reduces energy production, is known to be effective against cancer types that depend on oxidative phosphorylation. However, existing copper chelators are too toxic or ineffective for cancer treatment. Here we develop a safe, mitochondria-targeted, copper-depleting nanoparticle (CDN) and test it against triple-negative breast cancer (TNBC). We show that CDNs decrease oxygen consumption and oxidative phosphorylation, cause a metabolic switch to glycolysis and reduce ATP production in TNBC cells. This energy deficiency, together with compromised mitochondrial membrane potential and elevated oxidative stress, results in apoptosis. CDNs should be less toxic than existing copper chelators because they favorably deprive copper in the mitochondria in cancer cells instead of systemic depletion. Indeed, we demonstrate low toxicity of CDNs in healthy mice. In three mouse models of TNBC, CDN administration inhibits tumor growth and substantially improves survival. The efficacy and safety of CDNs suggest the potential clinical relevance of this approach.

[Application Value of Capillary Electrophoresis in Screeningß-Thalassemia of Children].

OBJECTIVE: to explore the value of capillary electrophoresis in screening ß- thalassemia of children, and to establish the cutoff values of HbA2 and HbF in our laboratory. METHODS: The data of hemoglobin capillary electrophoresis and genetic diagnosis of ß- thalassemia from 886 examined children were retrospectively analyzed. The cutoff values of HbA2 and HbF were determined by ROC curve. RESULTS: The cutoff value of HbA2 screening minor ß- thalassemia was 3.65%, the specificity was 0.996, and the sensitivity was 0.995. The cut-off value of HbF for screening minor ß- thalassemia was 1.45%, specificity was 0.751 and sensitivity was 0.675. Thus, 1 case with codon5 (CCT→C) mutation, 1 case with SEA -HPFH ß deletion, 1 case with - 28 (A→G) merger IVS-Ι-128 (T→G) double heterozygous mutations yet were found out, 1 case with 47 bp ß gene missing has not yet been reported in literature. CONCLUSION: Capillary electrophoresis has more high sensitivity and specificity in the screening of ß- thalassemia in children, especially for the detection of rare ß- thalassemia.

Carbon-coated FeCo nanoparticles as sensitive magnetic-particle-imaging tracers with photothermal and magnetothermal properties.

The low magnetic saturation of iron oxide nanoparticles, which are developed primarily as contrast agents for magnetic resonance imaging, limits the sensitivity of their detection using magnetic particle imaging (MPI). Here, we show that FeCo nanoparticles that have a core diameter of 10 nm and bear a graphitic carbon shell decorated with poly(ethylene glycol) provide an MPI signal intensity that is sixfold and fifteenfold higher than the signals from the superparamagnetic iron oxide tracers VivoTrax and Feraheme, respectively, at the same molar concentration of iron. We also show that the nanoparticles have photothermal and magnetothermal properties and can therefore be used for tumour ablation in mice, and that they have high optical absorbance in a broad near-infrared region spectral range (wavelength, 700-1,200 nm), making them suitable as tracers for photoacoustic imaging. As sensitive multifunctional and multimodal imaging tracers, carbon-coated FeCo nanoparticles may confer advantages in cancer imaging and hyperthermia therapy.

Trop2 is a driver of metastatic prostate cancer with neuroendocrine phenotype via PARP1.

Resistance to androgen deprivation therapy, or castration-resistant prostate cancer (CRPC), is often accompanied by metastasis and is currently the ultimate cause of prostate cancer-associated deaths in men. Recently, secondary hormonal therapies have led to an increase of neuroendocrine prostate cancer (NEPC), a highly aggressive variant of CRPC. Here, we identify that high levels of cell surface receptor Trop2 are predictive of recurrence of localized prostate cancer. Moreover, Trop2 is significantly elevated in CRPC and NEPC, drives prostate cancer growth, and induces neuroendocrine phenotype. Overexpression of Trop2 induces tumor growth and metastasis while loss of Trop2 suppresses these abilities in vivo. Trop2-driven NEPC displays a significant up-regulation of PARP1, and PARP inhibitors significantly delay tumor growth and metastatic colonization and reverse neuroendocrine features in Trop2-driven NEPC. Our findings establish Trop2 as a driver and therapeutic target for metastatic prostate cancer with neuroendocrine phenotype and suggest that high Trop2 levels could identify cancers that are sensitive to Trop2-targeting therapies and PARP1 inhibition.