In photoacoustic imaging, the second near-infrared (NIR-II) window is where tissue generates the least background signal. However, the large size of the few available contrast agents in this spectral ...range impedes their pharmacokinetics and decreases their thermal stability, leading to unreliable photoacoustic imaging. Here, we report the synthesis of miniaturized gold nanorods absorbing in the NIR-II that are 5-11 times smaller than regular-sized gold nanorods with a similar aspect ratio. Under nanosecond pulsed laser illumination, small nanorods are about 3 times more thermally stable and generate 3.5 times stronger photoacoustic signal than their absorption-matched larger counterparts. These unexpected findings are confirmed using theoretical and numerical analysis, showing that photoacoustic signal is not only proportional to the optical absorption of the nanoparticle solution but also to the surface-to-volume ratio of the nanoparticles. In living tumour-bearing mice, these small targeted nanorods display a 30% improvement in efficiency of agent delivery to tumours and generate 4.5 times greater photoacoustic contrast.
Noninvasive techniques, such as breath tests (urea breath test), blood pressure measurements using a sphygmomanometer and electrocardiography, were employed by a physician to perform classical ...diagnosis. The use of state-of-the-art noninvasive therapies at the organ level in modern medicine has gradually become possible. However, cancer treatment demands spatially and temporally controlled noninvasive therapy at the cell level because nonspecific toxicity often causes complicated side effects. To increase survival in cancer patients further, combination therapy and combination drugs are explored which demand high specificity to avoid combined-drug side effects. We believe that high specificity could be obtained by implementing near-infrared (NIR) light-assisted nanoparticles in photothermal therapy, chemotherapy, and photodynamic therapy. To refine this therapy and subsequently achieve high efficiency, novel nanomaterials have been designed and modified either to enhance the uptake and drug delivery to the cancer site, or control treatment to administer therapy efficiently. These modifications and developments have been demonstrated to achieve spatial and temporal control when conducting an
in vivo
xenograft, because the NIR light penetrated effectively the biological tissue. The nanoplatforms discussed in this review are grouped under the following subheadings: Au nanorods (NRs), Au nanoshells, other Au-related nanomaterials, graphene oxide, upconversion nanoparticles, and other related materials (including materials such as CuS, Fe
3
O
4
-related systems, and carbon nanotubes (CNTs)).
Near-infrared light sensitive nanomaterials provide ideal nanoplatforms in site specific noninvasive cancer therapy.
Glycosylated hemoglobin (HbA1c) targets for patients with chronic kidney disease (CKD) and type 2 diabetes remain controversial. To evaluate whether baseline HbA
1c
and HbA
1c
trajectories are ...associated with the risk of end-stage kidney disease (ESKD) and all-cause mortality, we recruited adult patients with CKD and type 2 diabetes from a “Pre-ESKD Program” at a medical center in Taiwan from 2003 to 2017. Group-based trajectory modeling was performed to identify distinct patient groups that contained patients with similar longitudinal HbA1c patterns. Cox proportional hazard models were used to estimate hazard ratios (HRs) of ESKD and mortality associated with baseline HbA
1c
levels and HbA
1c
trajectories. In the analysis related to baseline HbA
1c
(
n
= 4543), the adjusted HRs 95% confidence interval (CI) of all-cause mortality were 1.06 (0.95–1.18) and 1.25 (95% CI, 1.07–1.46) in patients with an HbA
1c
level of 7%–9% (53–75 mmol/mol) and >9% (>75 mmol/mol), respectively, as compared with those with an HbA1c level < 7% (<53 mmol/mol). In the trajectory analysis
(n
= 2692), three distinct longitudinal HbA
1c
trajectories were identified: nearly optimal (55.9%), moderate to stable (34.2%), and poor control (9.9%). Compared with the “nearly optimal” HbA
1c
trajectory group, the “moderate-to-stable” group did not have significantly higher mortality, but the “poorly controlled” group had 35% higher risk of mortality (adjusted HR = 1.35, 95% CI = 1.06–1.71). Neither baseline levels of HbA
1c
nor trajectories were associated with ESKD risk. In conclusion, in patients with CKD and type 2 diabetes, poor glycemic control was associated with an elevated risk of mortality but not associated with a risk of progression to ESKD.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Multidrug resistance (MDR) occurs frequently after long-term chemotherapy, resulting in refractory cancer and tumor recurrence. Therefore, combatting MDR is an important issue. Autophagy, a ...self-degradative system, universally arises during the treatment of sensitive and MDR cancer. Autophagy can be a double-edged sword for MDR tumors: it participates in the development of MDR and protects cancer cells from chemotherapeutics but can also kill MDR cancer cells in which apoptosis pathways are inactive. Autophagy induced by anticancer drugs could also activate apoptosis signaling pathways in MDR cells, facilitating MDR reversal. Therefore, research on the regulation of autophagy to combat MDR is expanding and is becoming increasingly important. We summarize advanced studies of autophagy in MDR tumors, including the variable role of autophagy in MDR cancer cells.
Abstract
The widespread use of proton exchange membrane water electrolysis requires the development of more efficient electrocatalysts containing reduced amounts of expensive iridium for the oxygen ...evolution reaction (OER). Here we present the identification of 6H-phase SrIrO
3
perovskite (6H-SrIrO
3
) as a highly active electrocatalyst with good structural and catalytic stability for OER in acid. 6H-SrIrO
3
contains 27.1 wt% less iridium than IrO
2
, but its iridium mass activity is about 7 times higher than IrO
2
, a benchmark electrocatalyst for the acidic OER. 6H-SrIrO
3
is the most active catalytic material for OER among the iridium-based oxides reported recently, based on its highest iridium mass activity. Theoretical calculations indicate that the existence of face-sharing octahedral dimers is mainly responsible for the superior activity of 6H-SrIrO
3
thanks to the weakened surface Ir-O binding that facilitates the potential-determining step involved in the OER (i.e., O* + H
2
O → HOO* + H
+
+
e
¯
).
Botulinum neurotoxins (BoNTs) cause flaccid paralysis by interfering with vesicle fusion and neurotransmitter release in the neuronal cells. BoNTs are the most widely used therapeutic proteins. ...BoNT/A was approved by the U.S. FDA to treat strabismus, blepharospam, and hemificial spasm as early as 1989 and then for treatment of cervical dystonia, glabellar facial lines, axillary hyperhidrosis, chronic migraine and for cosmetic use. Due to its high efficacy, longevity of action and satisfactory safety profile, it has been used empirically in a variety of ophthalmological, gastrointestinal, urological, orthopedic, dermatological, secretory, and painful disorders. Currently available BoNT therapies are limited to neuronal indications with the requirement of periodic injections resulting in immune-resistance for some indications. Recent understanding of the structure-function relationship of BoNTs prompted the engineering of novel BoNTs to extend therapeutic interventions in non-neuronal systems and to overcome the immune-resistance issue. Much research still needs to be done to improve and extend the medical uses of BoNTs.
Dye and nitro-compound pollution has become a significant issue worldwide. The adsorption and degradation of dyes and nitro-compounds have recently become important areas of study. Different methods, ...such as precipitation, flocculation, ultra-filtration, ion exchange, coagulation, and electro-catalytic degradation have been adopted for the adsorption and degradation of these organic pollutants. Apart from these methods, adsorption, photocatalytic degradation, and chemical degradation are considered the most economical and efficient to control water pollution from dyes and nitro-compounds. In this review, different kinds of dyes and nitro-compounds, and their adverse effects on aquatic organisms and human beings, were summarized in depth. This review article covers the comprehensive analysis of the adsorption of dyes over different materials (porous polymer, carbon-based materials, clay-based materials, layer double hydroxides, metal-organic frameworks, and biosorbents). The mechanism and kinetics of dye adsorption were the central parts of this study. The structures of all the materials mentioned above were discussed, along with their main functional groups responsible for dye adsorption. Removal and degradation methods, such as adsorption, photocatalytic degradation, and chemical degradation of dyes and nitro-compounds were also the main aim of this review article, as well as the materials used for such degradation. The mechanisms of photocatalytic and chemical degradation were also explained comprehensively. Different factors responsible for adsorption, photocatalytic degradation, and chemical degradation were also highlighted. Advantages and disadvantages, as well as economic cost, were also discussed briefly. This review will be beneficial for the reader as it covers all aspects of dye adsorption and the degradation of dyes and nitro-compounds. Future aspects and shortcomings were also part of this review article. There are several review articles on all these topics, but such a comprehensive study has not been performed so far in the literature.
Two-dimensional metal-organic frameworks represent a family of materials with attractive chemical and structural properties, which are usually prepared in the form of bulk powders. Here we show a ...generic approach to fabricate ultrathin nanosheet array of metal-organic frameworks on different substrates through a dissolution-crystallization mechanism. These materials exhibit intriguing properties for electrocatalysis including highly exposed active molecular metal sites owning to ultra-small thickness of nanosheets, improved electrical conductivity and a combination of hierarchical porosity. We fabricate a nickel-iron-based metal-organic framework array, which demonstrates superior electrocatalytic performance towards oxygen evolution reaction with a small overpotential of 240 mV at 10 mA cm
, and robust operation for 20,000 s with no detectable activity decay. Remarkably, the turnover frequency of the electrode is 3.8 s
at an overpotential of 400 mV. We further demonstrate the promise of these electrodes for other important catalytic reactions including hydrogen evolution reaction and overall water splitting.
Pancreatic ductal adenocarcinoma (PDAC) is the most common type of pancreatic cancer featured with high intra-tumoral heterogeneity and poor prognosis. To comprehensively delineate the PDAC ...intra-tumoral heterogeneity and the underlying mechanism for PDAC progression, we employed single-cell RNA-seq (scRNA-seq) to acquire the transcriptomic atlas of 57,530 individual pancreatic cells from primary PDAC tumors and control pancreases, and identified diverse malignant and stromal cell types, including two ductal subtypes with abnormal and malignant gene expression profiles respectively, in PDAC. We found that the heterogenous malignant subtype was composed of several subpopulations with differential proliferative and migratory potentials. Cell trajectory analysis revealed that components of multiple tumor-related pathways and transcription factors (TFs) were differentially expressed along PDAC progression. Furthermore, we found a subset of ductal cells with unique proliferative features were associated with an inactivation state in tumor-infiltrating T cells, providing novel markers for the prediction of antitumor immune response. Together, our findings provide a valuable resource for deciphering the intra-tumoral heterogeneity in PDAC and uncover a connection between tumor intrinsic transcriptional state and T cell activation, suggesting potential biomarkers for anticancer treatment such as targeted therapy and immunotherapy.
The role of long noncoding RNA (lncRNA) in adult hearts is unknown; also unclear is how lncRNA modulates nucleosome remodelling. An estimated 70% of mouse genes undergo antisense transcription, ...including myosin heavy chain 7 (Myh7), which encodes molecular motor proteins for heart contraction. Here we identify a cluster of lncRNA transcripts from Myh7 loci and demonstrate a new lncRNA-chromatin mechanism for heart failure. In mice, these transcripts, which we named myosin heavy-chain-associated RNA transcripts (Myheart, or Mhrt), are cardiac-specific and abundant in adult hearts. Pathological stress activates the Brg1-Hdac-Parp chromatin repressor complex to inhibit Mhrt transcription in the heart. Such stress-induced Mhrt repression is essential for cardiomyopathy to develop: restoring Mhrt to the pre-stress level protects the heart from hypertrophy and failure. Mhrt antagonizes the function of Brg1, a chromatin-remodelling factor that is activated by stress to trigger aberrant gene expression and cardiac myopathy. Mhrt prevents Brg1 from recognizing its genomic DNA targets, thus inhibiting chromatin targeting and gene regulation by Brg1. It does so by binding to the helicase domain of Brg1, a domain that is crucial for tethering Brg1 to chromatinized DNA targets. Brg1 helicase has dual nucleic-acid-binding specificities: it is capable of binding lncRNA (Mhrt) and chromatinized--but not naked--DNA. This dual-binding feature of helicase enables a competitive inhibition mechanism by which Mhrt sequesters Brg1 from its genomic DNA targets to prevent chromatin remodelling. A Mhrt-Brg1 feedback circuit is thus crucial for heart function. Human MHRT also originates from MYH7 loci and is repressed in various types of myopathic hearts, suggesting a conserved lncRNA mechanism in human cardiomyopathy. Our studies identify a cardioprotective lncRNA, define a new targeting mechanism for ATP-dependent chromatin-remodelling factors, and establish a new paradigm for lncRNA-chromatin interaction.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK