The role of sirtuins in intervertebral disc degeneration: Mechanisms and therapeutic potential.

Intervertebral disc degeneration (IDD) is one of the main causes of low back pain, which affects the patients' quality of life and health and imposes a significant socioeconomic burden. Despite great efforts made by researchers to understand the pathogenesis of IDD, effective strategies for preventing and treating this disease remain very limited. Sirtuins are a highly conserved family of (NAD+)-dependent deacetylases in mammals that are involved in a variety of metabolic processes in vivo. In recent years, sirtuins have attracted much attention owing to their regulatory roles in IDD on physiological activities such as inflammation, apoptosis, autophagy, aging, oxidative stress, and mitochondrial function. At the same time, many studies have explored the therapeutic effects of sirtuins-targeting activators or micro-RNA in IDD. This review summarizes the molecular pathways of sirtuins involved in IDD, and summarizes the therapeutic role of activators or micro-RNA targeting Sirtuins in IDD, as well as the current limitations and challenges, with a view to provide possible solutions for the treatment of IDD.

Sub-picosecond tunable mid-infrared light source for driving high-efficiency optical rectification.

Optical rectification (OR) is a popular way to generate coherent terahertz radiation. Here, we develop a sub-picosecond mid-infrared (mid-IR) light source with a tailored wavelength and pulse duration for enhancing the OR efficiency. Numerical simulations for a LiNbO3-based OR with tilted pulse-front excitation are first conducted to determine the optimal parameters of pump wavelength and pulse duration, demonstrating that the OR efficiency pumped by 4-µm sub-picosecond (0.5-0.6 ps) pulses is approximately twice the value with 0.8-µm pump at the same conditions. Guided by the simulation results, we build a BaGa4Se7-based optical parametric chirped-pulse amplification system with 1030-nm thin-disk pump and broadband mid-IR seeds. The output performances of >200-µJ pulse energy, ∼600-fs pulse duration and 1-kHz pulse repetition rate are achieved in a spectral range tunable from 3.5 to 5 µm. The large energy scalability and high parameter tunability make the light source attractive to high-efficiency OR in various materials.

Improvement on Magnetocaloric Effect through Structural Evolution in Gadolinium Borate Halides Ba2Gd(BO3)2X (X = F, Cl).

A new Gd3+-containing borate Ba2Gd(BO3)2F has been successfully grown via the high-temperature solution method using BaF2-NaF-B2O3 flux. Ba2Gd(BO3)2F crystallizing in the orthorhombic space group Pnma is with lattice parameters a = 7.571(4) Å, b = 10.424(5) Å, c = 8.581(4) Å, α = ß = γ = 90°, and Z = 2. Its three-dimensional framework was constructed from interesting pinwheel-like [Gd(BO3)F]∞ layers bridged by sharing [BO3]3-, which is different from the [Gd(BO3)]∞ layer in the model structure Ba2Gd(BO3)2Cl. The magnetic measurements indicated that Ba2Gd(BO3)2F has a larger magnetocaloric effect with -ΔSm,max = 27.82 J·kg-1·K-1at 2 K and 9 T than that of Ba2Gd(BO3)2Cl under the same conditions. Moreover, thermal stability, infrared spectrum (IR), and ultraviolet-visible-near-infrared diffuse reflectance spectrum were carried out to characterize the title compounds. The first-principles computations also looked into the electronic band structures, densities of states, and refractive indices.

Sr14.06Gd14.63(BO3)24: A Gadolinium-Rich Borate with Magnetic Refrigeration Performance.

A single crystal of Sr14.06Gd14.63(BO3)24 has been successfully grown through a high-temperature solution technique with K2O-KF-B2O3 as the flux. It crystallizes in the Pnma space group with parameters a = 22.3153(5) Å, b = 15.9087(4) Å, c = 8.7507(2) Å, and Z = 2. Sr14.06Gd14.63(BO3)24 has a three-dimensional (3D) framework built from [GdO] chains, in which the isolate [BO3]3- groups and Sr2+ ions fill in the space of the 3D framework. The magnetic measurements revealed that the title compound exhibits a large magnetocaloric effect with the magnetic entropy change of -ΔSm = 42.2 J kg-1 K-1 at 2 K for 7 T, which is higher than that of the commercial material, Gd3Ga5O12 (GGG), with -ΔSm of 38.4 J kg-1 K-1 under the same conditions. Moreover, the infrared spectrum (IR), UV-vis-NIR diffuse reflectance spectrum, and thermal stability were investigated.

Growth, Structure, and Properties of a Multifunctional Crystal Pr2CaB10O19.

A new praseodymium-based borate crystal Pr2CaB10O19 (PCB) has been grown through the high temperature solution method. PCB crystallizes in monoclinic space group C2 with unit cell parameters of a = 10.9475(10) Å, b = 6.5343(7) Å, c = 9.0336(8) Å, ß = 91.652(3)°, and Z = 2, in which B5O12 groups and PrO10 and CaO8 polyhedra constitute the three-dimensional framework. PCB exhibits a similar second harmonic response intensity to that of La2CaB10O19 and an intense orange fluorescence emission with a long fluorescence lifetime at about 610 nm excited by a xenon lamp light of 466 nm. The band gap, partial density of states, and birefringence have been investigated via theoretical calculations.

Large Magnetocaloric Effect in Li3K9Gd3(BO3)7 Crystal Featuring Sandwich-Like Three-Dimensional Framework.

A new Gd-based borate crystal, Li3K9Gd3(BO3)7, has been successfully obtained via the high-temperature solution method using Li2O-K2O-B2O3 self-flux. It crystallizes in monoclinic space group P2/n (no. 10) with lattice parameters a = 11.3454(6) Å, b = 9.9881(4) Å, c = 11.4467(7) Å, α = γ = 90 o, ß = 114.782(7) o, and Z = 2. Li3K9Gd3(BO3)7 exhibits an intriguing sandwich-like three-dimensional (3D) framework constructed from [Gd-B-O]∞ layers, KOn (n = 6 and 8) polyhedra, and LiO4 tetrahedra, in which [Gd-B-O]∞ layers are built from two types of GdO8 polyhedra and triangular BO3 units. Magnetic measurements showed that Li3K9Gd3(BO3)7 exhibits a large magnetocaloric effect with -ΔSm = 39.3 J kg-1 K-1 at 2.0 K for ΔH = 7 T, which is slightly higher than that of the commercial gadolinium gallium garnet under the same conditions. The powder X-ray diffraction, infrared spectrum, and UV-vis-NIR diffuse reflectance spectrum were also performed to characterize Li3K9Gd3(BO3)7. The electronic band structures, partial density of states, and refractive indices of Li3K9Gd3(BO3)7 were investigated via the first-principle calculations.

Na3Bi(IO3)6: An Alkali-Metal Bismuth Iodate with Intriguing One-Dimensional [BiI6O18] Chains and Pressure-Induced Structural Transition.

An alkali-metal bismuth iodate, Na3Bi(IO3)6, was successfully obtained by the hydrothermal method for the first time and contains intriguing one-dimensional [BiI6O18] chains. High-pressure Raman spectra were carried out to investigate the structural transition of Na3Bi(IO3)6. Electronic states and anisotropic optical responses were also investigated by theoretical calculations.

PIP4K2A regulates intracellular cholesterol transport through modulating PI(4,5)P2 homeostasis.

The transport of LDL-derived cholesterol from lysosomes to peroxisomes is facilitated by membrane contacts formed between the lysosomal protein synaptotagmin VII and the peroxisomal lipid phosphatidylinositol 4, 5-bisphosphate [PI(4,5)P2]. Here, we used RNA interference to search for regulators of PI(4,5)P2 and to study the effects of altered PI(4,5)P2 homeostasis on cholesterol transport. We found that knockdown of phosphatidylinositol 5-phosphate 4-kinase type-2 α (PIP4K2A) reduced peroxisomal PI(4,5)P2 levels, decreased lysosome-peroxisome membrane contacts, and increased accumulation of lysosomal cholesterol in human SV-589 fibroblasts. Forced expression of peroxisome-localized, kinase-active PIP4K2A in the knockdown cells reduced cholesterol accumulation, and in vitro addition of recombinant PIP4K2A restored membrane contacts. These results suggest that PIP4K2A plays a critical role in intracellular cholesterol transport by upregulating PI(4,5)P2 levels in the peroxisomal membrane. Further research into PIP4K2A activity may inform future therapeutic interventions for managing lysosomal storage disorders.

The role of Map1b in regulating osteoblast polarity, proliferation, differentiation and migration.

Osteoblast polarity, proliferation, differentiation, and migration are essential for maintaining normal bone structure and function. While the microtubule-associated protein Map1b has been extensively studied in nerve cells, its role in bone cells is less known. We investigated the functional significance of Map1b in mouse bone marrow stromal cells (ST2) and elucidated its relationship and influence on cytoskeletal polarity and Golgi organization. Our results suggest that Map1b, as a microtubule regulatory protein, can also regulate the expression of cyclin PCNA, p-H3(S10) and migration-related protein integrin ß1, thereby affecting the proliferation and migration of osteoblasts. The downstream target gene Rgc32 was screened by RNA sequencing. Furthermore, Map1b, as a downstream mediator, regulates the Wnt5a signaling pathway. This study expands our understanding of the involvement of Map1b in bone biology and highlights its crucial role in governing osteoblast polarity, proliferation, and migration, thereby providing a basis for developing novel therapeutic strategies targeting Map1b in orthopedic medicine and promoting precision treatment modalities. Further investigations on the precise mechanisms underlying Map1b's influence on bone cell function and disease progression are needed.

High-energy noncollinear optical parametric-chirped pulse amplification in LBO at 800 nm.

The optical parametric-chirped pulse amplification (OPCPA) based on large-aperture nonlinear optical crystals is promising for implementation of an ultrahigh peak-power laser system of 10 PW and beyond. We demonstrated the highest energy broadband OPCPA at 800 nm, to the best of our knowledge, by using an 80 mm in diameter LiB(3)O(5)(LBO) amplifier, with an output energy of 28.68 J, a bandwidth of 80 nm (FWHM), and conversion efficiency of 25.38%. After compression, a peak power of 0.61 PW with 33.8 fs pulse duration is produced.

Applications of Hydrogels in Drug Delivery for Oral and Maxillofacial Diseases.

Oral and maxillofacial diseases have an important impact on local function, facial appearance, and general health. As a multifunctional platform, hydrogels are widely used in the biomedical field due to their excellent physicochemical properties. In recent years, a large number of studies have been conducted to adapt hydrogels to the complex oral and maxillofacial environment by modulating their pore size, swelling, degradability, stimulus-response properties, etc. Meanwhile, many studies have attempted to use hydrogels as drug delivery carriers to load drugs, cytokines, and stem cells for antibacterial, anticancer, and tissue regeneration applications in oral and maxillofacial regions. This paper reviews the application and research progress of hydrogel-based drug delivery systems in the treatment of oral and maxillofacial diseases such as caries, endodontic diseases, periodontal diseases, maxillofacial bone diseases, mucosal diseases, oral cancer, etc. The characteristics and applications of hydrogels and drug-delivery systems employed for the treatment of different diseases are discussed in order to provide a reference for further research on hydrogel drug-delivery systems in the future.

[Rat alveolar type II injured by bleomycin].

OBJECTIVE: To explore dysfunction mechanism of rat alveolar type II (AT-II) injured by bleomycin (BLM). METHODS: SD rats were injected with a single intratracheal dose of bleomycin or control saline. On day 7, 14, and 28 following intratracheal bleomycin or saline instillation, animals were killed under overdose of 1.5% sodium pentobarbital (0.25 ml/100 g, i.p.) and bronchoalveolar lavage fluid (BALF) from the lung was tested for the activity of pulmonary surfactant (PS) by the Whihelmy Film Balance. Several concentrations of bleomycin stimulated the culture of rat AT-II cells, and surfactant protein (SP) A, B, and aquaporin-1 (AQP) mRNA were analyzed by fluorescent quantitative polymerase chain reaction (FQ-PCR). RESULTS: The activity of PS and hypoxemia significantly decreased on day 7 and improved on day 14 and completely recovered to normal status on day 28. SP-A, B, and AQP-1 mRNA expression in BLM-stimulated group were significantly lower than those in the control group (P<0.001). CONCLUSION: BLM-injured AT-II cells decrease the levels of SP-A, B, and AQP-1 mRNA and cause PS dysfunction, resulting in hypoxemia and pneumonedema.

[The protective effects of Fufang Biejiafang on bleomycin-induced pulmonary fibrosis in rats].

OBJECTIVE: To explore the possible effects and mechanism of Fufang Biejiafang on a single intratracheal instillation (IT) of bleomycin-induced lung fibrosis model. METHOD: SD rats were treated with a single IT dose of bleomycin or control saline. Chinese medicine group were poured into the stomach after the first day of operation with high dosage, middle dosage and low dosage. On days 7, 14 and 28 following IT bleomycin or saline, 4 mL blood were taken from the abdominal aorta for arterial blood gas analysis. The left lung was fixed for routine light microscopic examination. Bronchoalveolar lavage fluid (BALF) from the right lung was tested the activity of pulmonary surfactant (PS) by the Whihelmy Film Balance, then the right lung was frozen immediately in liquid nitrogen for determination of hydroxyproline concentration. RESULT: Model rats had obviously changes of body weight and hypoxemia and dysfunction of PS on days 7 and improved on days 14. Compared with three dose groups, the middle dose group some degreely improved and PS function. It ameliorate fibrosis because of inhibition of inflammation. CONCLUSION: (1) PS dysfunction resulted in hypoxemia after bleomycin injured alveolar type II (AT II). Fufang biejiafang-middle dose-group ameliorate hypoxemia by remission AT-II injury. (2) Fufang biejiafang may inhibit exudation inflammation and ameliorate fibrosis.