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1.
Natl Sci Rev ; 11(7): nwae167, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38887543

ABSTRACT

Radiotherapy is widely used for cancer treatment, but its clinical utility is limited by radioresistance and its inability to target metastases. Nanoscale metal-organic frameworks (MOFs) have shown promise as high-Z nanoradiosensitizers to enhance radiotherapy and induce immunostimulatory regulation of the tumor microenvironment. We hypothesized that MOFs could deliver small-molecule therapeutics to synergize with radiotherapy for enhanced antitumor efficacy. Herein, we develop a robust nanoradiosensitizer, GA-MOF, by conjugating a STING agonist, 2',3'-cyclic guanosine monophosphate-adenosine monophosphate (GA), on MOFs for synergistic radiosensitization and STING activation. GA-MOF demonstrated strong anticancer efficacy by forming immune-cell-rich nodules (artificial leukocytoid structures) and transforming them into immunostimulatory hotspots with radiotherapy. Further combination with an immune checkpoint blockade suppressed distant tumors through systemic immune activation. Our work not only demonstrates the potent radiosensitization of GA-MOF, but also provides detailed mechanisms regarding MOF distribution, immune regulatory pathways and long-term immune effects.

3.
Angew Chem Int Ed Engl ; 63(16): e202319981, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38381713

ABSTRACT

Chemoradiotherapy combines radiotherapy with concurrent chemotherapy to potentiate antitumor activity but exacerbates toxicities and causes debilitating side effects in cancer patients. Herein, we report the use of a nanoscale metal-organic layer (MOL) as a 2D nanoradiosensitizer and a reservoir for the slow release of chemotherapeutics to amplify the antitumor effects of radiotherapy. Coordination of phosphate-containing drugs to MOL secondary building units prolongs their intratumoral retention, allowing for continuous release of gemcitabine monophosphate (GMP) for effective localized chemotherapy. In the meantime, the MOL sensitizes cancer cells to X-ray irradiation and provides potent radiotherapeutic effects. GMP-loaded MOL (GMP/MOL) enhances cytotoxicity by 2-fold and improves radiotherapeutic effects over free GMP in vitro. In a colon cancer model, GMP/MOL retains GMP in tumors for more than four days and, when combined with low-dose radiotherapy, inhibits tumor growth by 98 %. The synergistic chemoradiotherapy enabled by GMP/MOL shows a cure rate of 50 %, improves survival, and ameliorates cancer-proliferation histological biomarkers.


Subject(s)
Neoplasms , Phosphates , Humans , Gemcitabine , Chemoradiotherapy , Neoplasms/drug therapy
5.
Psychiatr Serv ; 74(11): 1215-1216, 2023 11 01.
Article in English | MEDLINE | ID: mdl-37908080
6.
Small ; 19(52): e2305440, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37635106

ABSTRACT

Cancer cells alter mechanical tension in their cell membranes. New interventions to regulate cell membrane tension present a potential strategy for cancer therapy. Herein, the increase of cell membrane tension by cholesterol oxidase (COD) via cholesterol depletion in vitro and the design of a COD-functionalized nanoscale metal-organic framework, Hf-TBP/COD, for cholesterol depletion and mechanoregulation of tumors in vivo, are reported. COD is found to deplete cholesterol and disrupt the mechanical properties of lipid bilayers, leading to decreased cell proliferation, migration, and tolerance to oxidative stress. Hf-TBP/COD increases mechanical tension of plasma membranes and osmotic fragility of cancer cells, which induces influx of calcium ions, inhibits cell migration, increases rupturing propensity for effective caspase-1 mediated pyroptosis, and decreases tolerance to oxidative stress. In the tumor microenvironment, Hf-TBP/COD downregulates multiple immunosuppressive checkpoints to reinvigorate T cells and enhance T cell infiltration. Compared to Hf-TBP, Hf-TBP/COD improves anti-tumor immune response and tumor growth inhibition from 54.3% and 79.8% to 91.7% and 95% in a subcutaneous triple-negative breast cancer model and a colon cancer model, respectively.


Subject(s)
Metal-Organic Frameworks , Neoplasms , Humans , Metal-Organic Frameworks/pharmacology , Cholesterol Oxidase , Pyroptosis , T-Lymphocytes , Cholesterol , Tumor Microenvironment
8.
Nat Plants ; 9(7): 1154-1168, 2023 07.
Article in English | MEDLINE | ID: mdl-37349550

ABSTRACT

Wood cellulose microfibril (CMF) is the most abundant organic substance on Earth but its nanostructure remains poorly understood. There are controversies regarding the glucan chain number (N) of CMFs during initial synthesis and whether they become fused afterward. Here, we combined small-angle X-ray scattering, solid-state nuclear magnetic resonance and X-ray diffraction analyses to resolve CMF nanostructures in native wood. We developed small-angle X-ray scattering measurement methods for the cross-section aspect ratio and area of the crystalline-ordered CMF core, which has a higher scattering length density than the semidisordered shell zone. The 1:1 aspect ratio suggested that CMFs remain mostly segregated, not fused. The area measurement reflected the chain number in the core zone (Ncore). To measure the ratio of ordered cellulose over total cellulose (Roc) by solid-state nuclear magnetic resonance, we developed a method termed global iterative fitting of T1ρ-edited decay (GIFTED), in addition to the conventional proton spin relaxation editing method. Using the formula N = Ncore/Roc, most wood CMFs were found to contain 24 glucan chains, conserved between gymnosperm and angiosperm trees. The average CMF has a crystalline-ordered core of ~2.2 nm diameter and a semidisordered shell of ~0.5 nm thickness. In naturally and artificially aged wood, we observed only CMF aggregation (contact without crystalline continuity) but not fusion (forming a conjoined crystalline unit). This further argued against the existence of partially fused CMFs in new wood, overturning the recently proposed 18-chain fusion hypothesis. Our findings are important for advancing wood structural knowledge and more efficient use of wood resources in sustainable bio-economies.


Subject(s)
Microfibrils , Wood , Cellulose/chemistry , Magnetic Resonance Spectroscopy , Seeds
9.
Angew Chem Int Ed Engl ; 62(22): e202301910, 2023 05 22.
Article in English | MEDLINE | ID: mdl-36997341

ABSTRACT

The efficacy of photodynamic therapy (PDT) depends on the subcellular localization of photosensitizers. Herein, we report a dual-organelle-targeted nanoparticle platform for enhanced PDT of cancer. By grafting 5-aminolevulinic acid (ALA) to a Hf12 -based nanoscale metal-organic layer (Hf-MOL) via carboxylate coordination, ALA/Hf-MOL enhanced ALA delivery and protoporphyrin IX (PpIX) synthesis in mitochondria, and trapped the Hf-MOL comprising 5,15-di-p-benzoatoporphyrin (DBP) photosensitizers in lysosomes. Light irradiation at 630 nm simultaneously excited PpIX and DBP to generate singlet oxygen and rapidly damage both mitochondria and lysosomes, leading to synergistic enhancement of the PDT efficacy. The dual-organelle-targeted ALA/Hf-MOL outperformed Hf-MOL in preclinical PDT studies, with a 2.7-fold lower half maximal inhibitory concentration in cytotoxicity assays in vitro and a 3-fold higher cure rate in a colon cancer model in vivo.


Subject(s)
Photochemotherapy , Porphyrins , Aminolevulinic Acid/pharmacology , Aminolevulinic Acid/therapeutic use , Photosensitizing Agents/pharmacology , Photosensitizing Agents/therapeutic use , Mitochondria , Metals , Cell Line, Tumor
10.
Cancer Med ; 12(7): 8378-8387, 2023 04.
Article in English | MEDLINE | ID: mdl-36562288

ABSTRACT

BACKGROUND: Small-cell lung cancer (SCLC) is the deadliest form of lung cancer but lacks targeted therapies. METHODS: We studied the effect of the natural product mistletoe lectin (ML) in pre-clinical models of SCLC, focusing on cell lines with amplification of the myc family oncogenes C-myc and N-myc. RESULTS: We found that ML treatment inhibits growth of SCLC cell lines in culture and induces apoptosis. ML treatment also decreases the expression of the amplified myc proteins. Over-expression of either C-myc or N-myc results in enhanced SCLC cell sensitivity to ML. In a mouse xenograft model of SCLC, treatment with ML results in decreased tumor growth over 4 weeks with evidence of increased apoptosis in tumors from treated animals. CONCLUSION: Overall, our results demonstrate that ML exhibits therapeutic potential in SCLC, that is at least partially dependent on myc protein expression.


Subject(s)
Biological Products , Carcinoma, Small Cell , Lung Neoplasms , Mistletoe , Small Cell Lung Carcinoma , Humans , Animals , Mice , Mistletoe/metabolism , Lectins/metabolism , Gene Amplification , Small Cell Lung Carcinoma/drug therapy , Small Cell Lung Carcinoma/genetics , Lung Neoplasms/drug therapy , Lung Neoplasms/genetics , Lung Neoplasms/metabolism , Proto-Oncogene Proteins c-myc/genetics , Proto-Oncogene Proteins c-myc/metabolism
11.
Angew Chem Int Ed Engl ; 61(46): e202208685, 2022 11 14.
Article in English | MEDLINE | ID: mdl-36149753

ABSTRACT

High-Z metal-based nanoscale metal-organic frameworks (nMOFs) with photosensitizing ligands can enhance radiation damage to tumors via a unique radiotherapy-radiodynamic therapy (RT-RDT) process. Here we report Monte Carlo (MC) simulation-guided design of a Th-based nMOF built from Th6 -oxo secondary building units and 5,15-di(p-benzoato)porphyrin (DBP) ligands, Th-DBP, for enhanced RT-RDT. MC simulations revealed that the Th-lattice outperformed the Hf-lattice in radiation dose enhancement owing to its higher mass attenuation coefficient. Upon X-ray or γ-ray radiation, Th-DBP enhanced energy deposition, generated more reactive oxygen species, and induced significantly higher cytotoxicity to cancer cells over the previously reported Hf-DBP nMOF. With low-dose X-ray irradiation, Th-DBP suppressed tumor growth by 88 % in a colon cancer and 97 % in a pancreatic cancer mouse model.


Subject(s)
Colonic Neoplasms , Metal-Organic Frameworks , Nanostructures , Mice , Animals , Metal-Organic Frameworks/therapeutic use , Metal-Organic Frameworks/radiation effects , Thorium , Monte Carlo Method , Ligands , Nanostructures/therapeutic use , Colonic Neoplasms/drug therapy
12.
Annu Int Conf IEEE Eng Med Biol Soc ; 2022: 886-890, 2022 07.
Article in English | MEDLINE | ID: mdl-36086545

ABSTRACT

Noise exposure is encountered nearly everyday in both recreational and occupational settings, and can lead to a number of health concerns including hearing-loss, tinnitus, social-isolation and possibly dementia. Although guidelines exist to protect workers from noise, it remains a challenge to accurately quantify the noise exposure experienced by an individual due to the complexity and non-stationarity of noise sources. This is especially true for impulsive noise sources, such as weapons fire and industrial impact noise which are difficult to quantify due to technical challenges relating to sensor design and size, weight and power requirements. Because of this, personal noise dosimeters are often limited to a maximum 140 dB SPL and are not sufficient to measure impulse noise. This work details the design of a body-worn noise dosimeter (mNOISE) that processes both impulse and continuous noise ranging in level from 40 dBA-185 dBP (i.e. a quiet whisper to a shoulder fired rocket). Also detailed is the capability of the device to log the kurtosis of the sound pressure waveform in real-time, which is thought to be useful in characterizing complex noise exposures. Finally, we demonstrate the use of mNOISE in a military-flight noise environment. Clinical Relevance- On-body noise exposure monitoring can be used by audiologists industrial hygiene personnel and others to determine threshold of injury adequate hearing protection requirements and ultimately reduce permanent noise-induced hearing loss.


Subject(s)
Hearing Loss, Noise-Induced , Noise, Occupational , Occupational Exposure , Hearing Loss, Noise-Induced/etiology , Hearing Loss, Noise-Induced/prevention & control , Humans , Noise, Occupational/adverse effects , Occupations , Radiation Dosimeters/adverse effects
13.
Chem Sci ; 13(29): 8526-8535, 2022 Jul 29.
Article in English | MEDLINE | ID: mdl-35974768

ABSTRACT

Extracellular accumulation of ß amyloid peptides of 40 (Aß40) and 42 residues (Aß42) has been considered as one of the hallmarks in the pathology of Alzheimer's disease. In this work, we are able to prepare oligomeric aggregates of Aß with uniform size and monomorphic structure. Our experimental design is to incubate Aß peptides in reverse micelles (RMs) so that the peptides could aggregate only through a single nucleation process and the size of the oligomers is confined by the physical dimension of the reverse micelles. The hence obtained Aß oligomers (AßOs) are 23 nm in diameter and they belong to the category of high molecular-weight (MW) oligomers. The solid-state NMR data revealed that Aß40Os adopt the structural motif of ß-loop-ß but the chemical shifts manifested that they may be structurally different from low-MW AßOs and mature fibrils. From the thioflavin-T results, we found that high-MW Aß42Os can accelerate the fibrillization of Aß40 monomers. Our protocol allows performing cross-seeding experiments among oligomeric species. By comparing the chemical shifts of Aß40Os cross seeded by Aß42Os and those of Aß40Os prepared in the absence of Aß42Os, we observed that the chemical states of E11, K16, and E22 were altered, whereas the backbone conformation of the ß-sheet region near the C-terminus was structurally invariant. The use of reverse micelles allows hitherto the most detailed characterization of the structural variability of Aß40Os.

14.
Mol Ther Nucleic Acids ; 28: 423-434, 2022 Jun 14.
Article in English | MEDLINE | ID: mdl-35505960

ABSTRACT

Small interfering RNA (siRNA) therapeutics have developed rapidly in recent years, despite the challenges associated with delivery of large, highly charged nucleic acids. Delivery of siRNA therapeutics to the liver has been established, with conjugation of siRNA to N-acetylgalactosamine (GalNAc) providing durable gene knockdown in hepatocytes following subcutaneous injection. GalNAc binds the asialoglycoprotein receptor (ASGPR) that is highly expressed on hepatocytes and exploits this scavenger receptor to deliver siRNA across the plasma membrane by endocytosis. However, siRNA needs to access the RNA-induced silencing complex (RISC) in the cytoplasm to provide effective gene knockdown, and the entire siRNA delivery process is very inefficient, likely because of steps required for endosomal escape, intracellular trafficking, and stability of siRNA. To reveal the cellular factors limiting delivery of siRNA therapeutics, we performed a genome-wide pooled knockout screen on the basis of delivery of GalNAc-conjugated siRNA targeting the HPRT1 gene in the human hepatocellular carcinoma line Hep3B. Our primary genome-wide pooled knockout screen identified candidate genes that when knocked out significantly enhanced siRNA efficacy in Hep3B cells. Follow-up studies indicate that knockout of RAB18 improved the efficacy of siRNA delivered by GalNAc, cholesterol, or antibodies, but not siRNA delivered by Lipofectamine transfection, suggesting a role for RAB18 in siRNA delivery and intracellular trafficking.

15.
Child Adolesc Psychiatr Clin N Am ; 31(2): 295-312, 2022 04.
Article in English | MEDLINE | ID: mdl-35361366

ABSTRACT

Supporting the mental health of youth who identify as Black, Indigenous, or Persons of Color (BIPOC) continues to be a challenge for clinicians and policymakers alike. Children and adolescents are a vulnerable population, and for BIPOC youth, these vulnerabilities are magnified by the effects of structural, interpersonal, and internalized racism. Integration of psychiatric care into other medical settings has emerged as an evidence-based method to improve access to psychiatric care, but to bridge the gap experienced by BIPOC youth, care must extend beyond medical settings to other child-focused sectors, including local governments, education, child welfare, juvenile legal systems, and beyond. Intentional policy decisions are needed to incentivize and support these systems, which typically rely on coordination and collaboration between clinicians and other stakeholders. Clinicians must be trauma-informed and strive for structural competency to successfully navigate and advocate for collaborative systems that benefit BIPOC youth.


Subject(s)
Mental Health , Racism , Adolescent , Child , Child Welfare , Family , Humans , Psychotherapy
16.
J Am Chem Soc ; 144(12): 5241-5246, 2022 03 30.
Article in English | MEDLINE | ID: mdl-35297640

ABSTRACT

Herein we report that dimensional reduction from three-dimensional nanoscale metal-organic frameworks (nMOFs) to two-dimensional nanoscale metal-organic layers (nMOLs) increases the frequency of encounters between photosensitizers and oxygen and facilitates the diffusion of singlet oxygen from the nMOL to significantly enhance photodynamic therapy. The nMOFs and nMOLs share the same M12-oxo (M = Zr, Hf) secondary building units and 5,15-di-p-benzoatoporphyrin (DBP) ligands but exhibit three-dimensional and two-dimensional topologies, respectively. Molecular dynamics simulations and experimental studies revealed that the nMOLs with a monolayer morphology enhanced the generation of reactive oxygen species and exhibited over an order of magnitude higher cytotoxicity over the nMOFs. In a mouse model of triple-negative breast cancer, Hf-DBP nMOL showed 49.1% more tumor inhibition, an 80% higher cure rate, and 16.3-fold lower metastasis potential than Hf-DBP nMOF.


Subject(s)
Metal-Organic Frameworks , Nanostructures , Neoplasms , Photochemotherapy , Animals , Metal-Organic Frameworks/pharmacology , Metal-Organic Frameworks/therapeutic use , Mice , Neoplasms/pathology , Photochemotherapy/methods , Photosensitizing Agents/pharmacology , Photosensitizing Agents/therapeutic use , Singlet Oxygen/therapeutic use
17.
Article in English | MEDLINE | ID: mdl-34631114

ABSTRACT

BACKGROUND: Jordan has received more than three million refugees from bordering countries during times of conflict, including over 600 000 Syrian refugees between 2011 and 2021. Amidst this humanitarian crisis, a new mental health system for Syrian refugees has developed in Jordan, with most clinical services administered through non-governmental organizations. Prior studies have identified increased risk of psychiatric disorders in refugee populations and significant barriers for Syrian refugees seeking mental health treatment, but few have reviewed the organization or ability of local systems to meet the needs of this refugee population. METHODS: Qualitative interviews of mental health professionals working with refugees in Jordan were conducted and thematically analyzed to assess efficacy and organizational dynamics. RESULTS: Interviewees described barriers to care inherent in many refugee settings, including financial limitations, shortages of mental health professionals, disparate geographic accessibility, stigma, and limited or absent screening protocols. Additional barriers not previously described in Jordan were identified, including clinician burnout, organizational metrics restricting services, insufficient visibility of services, and security restrictions. Advantages of the Jordanian system were also identified, including a receptive sociopolitical response fostering coordination and collaboration, open-door policies for accessing care, the presence of community and grassroots approaches, and improvements to health care infrastructure benefiting the local populace. CONCLUSIONS: These findings highlight opportunities and pitfalls for program development in Jordan and other middle- and low-income countries. Leveraging clinician input can promote health system efficacy and improve mental health outcomes for refugee patients.

18.
ACS Appl Mater Interfaces ; 13(29): 34742-34751, 2021 Jul 28.
Article in English | MEDLINE | ID: mdl-34264640

ABSTRACT

Cs4PbI6, as a rarely investigated member of the Cs4PbX6 (X is a halogen element) family, has been successfully synthesized at low temperatures, and the synthetic conditions have been optimized. Metal iodides such as LiI, KI, NiI2, CoI2, and ZnI2, as additives, play an important role in enhancing the formation of the Cs4PbI6 microcrystals. ZnI2 with the lowest dissociation energy is the most efficient additive to supply iodide ions, and its amount of addition has also been optimized. Strong red to near-infrared (NIR) emission properties have been detected, and its optical emission centers have been identified to be numerous embedded perovskite-type α-CsPbI3 nanocrystallites (∼5 nm in diameter) based on investigations of temperature- and pressure-dependent photoluminescent properties. High-resolution transmission electron microscopy was used to detect these hidden nanoparticles, although the material was highly beam-sensitive and confirmed a "raisin bread"-like structure of the Cs4PbI6 crystals. A NIR mini-LED for the biological application has been successfully fabricated using as-synthesized Cs4PbI6 crystals. This work provides information for the future development of infrared fluorescent nanoscale perovskite materials.

20.
Chem Commun (Camb) ; 57(34): 4110-4113, 2021 Apr 27.
Article in English | MEDLINE | ID: mdl-33908496

ABSTRACT

We present a first report on the detection of three different C6 conformers of cellulose in spruce, as revealed by solid-state 1H-13C correlation spectra. The breakthrough in 1H resolution is achieved by magic-angle spinning in the regime of 150 kHz. The suppression of dense dipolar network of 1H provides inverse detected 13C spectra at a good sensitivity even in natural samples. We find that the glycosidic linkages are initially more ordered in spruce than maple, but a thermal treatment of spruce leads to a more heterogeneous packing order of the remaining cellulose fibrils.

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