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1.
Appl Opt ; 63(11): 2916-2921, 2024 Apr 10.
Article in English | MEDLINE | ID: mdl-38856389

ABSTRACT

The laser output characteristics of N d:L u 2 O 3 crystals were investigated in detail to obtain a dual-wavelength all-solid-state laser. Using 806 nm LD end-face pumped N d:L u 2 O 3 crystals with lengths of 6 mm, a 1076 & 1080 nm laser outputs with a maximum output power of 3.73 W were obtained, with a slope efficiency of 30.4%, an optical-to-optical conversion efficiency of 28.5%, and a power stability of 0.41% for 4 h of continuous measurement. Furthermore, by suppressing the higher-order modes, a high beam quality laser output with beam quality factors of 2.092 and 1.589 in the x and y directions, respectively, and a maximum output power of 1.27 W were obtained. In addition, it was experimentally verified that both wavelengths of the output laser were elliptically polarized.

2.
PLoS One ; 19(6): e0305366, 2024.
Article in English | MEDLINE | ID: mdl-38843169

ABSTRACT

[This corrects the article DOI: 10.1371/journal.pone.0275998.].

3.
Zool Res ; 45(3): 633-647, 2024 May 18.
Article in English | MEDLINE | ID: mdl-38766746

ABSTRACT

Painful stimuli elicit first-line reflexive defensive reactions and, in many cases, also evoke second-line recuperative behaviors, the latter of which reflects the sensing of tissue damage and the alleviation of suffering. The lateral parabrachial nucleus (lPBN), composed of external- (elPBN), dorsal- (dlPBN), and central/superior-subnuclei (jointly referred to as slPBN), receives sensory inputs from spinal projection neurons and plays important roles in processing affective information from external threats and body integrity disruption. However, the organizational rules of lPBN neurons that provoke diverse behaviors in response to different painful stimuli from cutaneous and deep tissues remain unclear. In this study, we used region-specific neuronal depletion or silencing approaches combined with a battery of behavioral assays to show that slPBN neurons expressing substance P receptor ( NK1R) (lPBN NK1R) are crucial for driving pain-associated self-care behaviors evoked by sustained noxious thermal and mechanical stimuli applied to skin or bone/muscle, while elPBN neurons are dispensable for driving such reactions. Notably, lPBN NK1R neurons are specifically required for forming sustained somatic pain-induced negative teaching signals and aversive memory but are not necessary for fear-learning or escape behaviors elicited by external threats. Lastly, both lPBN NK1R and elPBN neurons contribute to chemical irritant-induced nocifensive reactions. Our results reveal the functional organization of parabrachial substrates that drive distinct behavioral outcomes in response to sustained pain versus external danger under physiological conditions.


Subject(s)
Nociception , Parabrachial Nucleus , Animals , Parabrachial Nucleus/physiology , Mice , Nociception/physiology , Neurons/physiology , Pain/physiopathology , Male , Behavior, Animal/physiology
4.
bioRxiv ; 2024 May 01.
Article in English | MEDLINE | ID: mdl-38746158

ABSTRACT

Acquired genetic alterations commonly drive resistance to endocrine and targeted therapies in metastatic breast cancer 1-7 , however the underlying processes engendering these diverse alterations are largely uncharacterized. To identify the mutational processes operant in breast cancer and their impact on clinical outcomes, we utilized a well-annotated cohort of 3,880 patient samples with paired tumor-normal sequencing data. The mutational signatures associated with apolipoprotein B mRNA-editing enzyme catalytic polypeptide-like 3 (APOBEC3) enzymes were highly prevalent and enriched in post-treatment compared to treatment-naïve hormone receptor-positive (HR+) cancers. APOBEC3 mutational signatures were independently associated with shorter progression-free survival on antiestrogen plus CDK4/6 inhibitor combination therapy in patients with HR+ metastatic breast cancer. Whole genome sequencing (WGS) of breast cancer models and selected paired primary-metastatic samples demonstrated that active APOBEC3 mutagenesis promoted resistance to both endocrine and targeted therapies through characteristic alterations such as RB1 loss-of-function mutations. Evidence of APOBEC3 activity in pre-treatment samples illustrated a pervasive role for this mutational process in breast cancer evolution. The study reveals APOBEC3 mutagenesis to be a frequent mediator of therapy resistance in breast cancer and highlights its potential as a biomarker and target for overcoming resistance.

5.
BMC Public Health ; 24(1): 1287, 2024 May 10.
Article in English | MEDLINE | ID: mdl-38730364

ABSTRACT

BACKGROUND: Frailty not only affects disease survival but also impacts the long-term function and quality life of all adults diagnosed with and/or treated for cancer.The American Heart Association has introduced Life's Essential 8 (LE8) as a novel metric for assessing cardiovascular health. Currently, LE8's application in evaluating the frailty of cancer survivors remains unreported. This research seeks to explore the connection between LE8 scores and frailty levels in cancer survivors across the United States, thereby addressing a significant void in existing studies. METHODS: This study analyzed data from cancer survivors enrolled in the National Health and Nutrition Examination Surveys (NHANES) spanning the years 2005 to 2018, providing a comprehensive dataset. Multivariable logistic regression models were used to examine the linkage between LE8 rankings and frailty condition in cancer survivors. Furthermore, the study delved deeper into this correlation using restricted cubic spline (RCS) curves and subgroup analyses. RESULTS: In the fully adjusted model, an increased LE8 level was closely associated with a reduced odds ratio of frailty among cancer survivors, with an OR of 0.95 (95% CI: 0.94-0.96, p < 0.0001).This pattern persisted across different categorizations of LE8 into low, moderate, and high groups, demonstrating a consistent trend. The analysis revealed a non-linear relationship between LE8 scores and frailty status, further supporting a straightforward association (p-value for non-linearity = 0.0729). CONCLUSION: Studies have found that the higher the LE8 score, the less likely a cancer patient is to develop debilitating symptoms.This indicates that the LE8 scores may provide an opportunity for interventions aimed at improving the prognosis of cancer patients.


Subject(s)
Cancer Survivors , Frailty , Nutrition Surveys , Humans , Male , United States/epidemiology , Female , Frailty/epidemiology , Cancer Survivors/statistics & numerical data , Cancer Survivors/psychology , Cross-Sectional Studies , Middle Aged , Aged , Adult , Quality of Life , Neoplasms/mortality
6.
Heliyon ; 10(8): e29275, 2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38699747

ABSTRACT

Background: The clinical significance of immune-related antigen CD58 in gliomas remains uncertain. The aim of this study was to examine the clinical importance and possible core related genes of CD58 in gliomas. Methods: Pan-cancer analysis was to observe the association between CD58 and different tumors, glioma RNA sequencing data and clinical sample analyses were used to observe the relationship between CD58 and glioma, shRNA interference models were to observe the impact of CD58 on glioma cell function, and four glioma datasets and two online analysis platforms were used to explore the core related genes affecting the correlation between CD58 and glioma. Results: High CD58 expression was associated with worse prognosis in various tumors and higher malignancy in glioma. Down regulation of CD58 expression was linked to decreased proliferation, increased apoptosis, and reduced metastasis in glioma cells. The pathways involved in CD58-related effects were enriched for immune cell adhesion and immune factor activation, and the core genes were CASP1, CCL2, IL18, MYD88, PTPRC, and TLR2. The signature of CD58 and its core-related genes showed superior predictive power for glioma prognosis. Conclusion: High CD58 expression is correlated with more malignant glioma types, and also an independent risk factor for mortality in glioma. CD58 and its core-related genes may serve as novel biomarkers for diagnosing and treating glioma.

7.
Article in English | MEDLINE | ID: mdl-38702472

ABSTRACT

RATIONALE: Methamphetamine addiction is a persistent and intractable pathological learning and memory, whereas no approved therapeutics is available. However, few attentions have been paid to how associative learning participates in the formation of intractable memory related to drug addiction OBJECTIVES AND METHODS: To investigate the role of associative learning in methamphetamine addiction and the underlying neurobiological mechanism, methamphetamine self-administration, oral sucrose self-administration, chemogenetic neuromanipulation, and fiber photometry in mice were performed in this study. RESULTS: We reported that associative learning increased methamphetamine-induced self-administration, but not oral sucrose self-administration. In addition, the enhancement of methamphetamine-induced self-administration was independent of more methamphetamine consumption, and remained with higher drug-taking and motivation in the absence of visual cues, suggesting the direct effects of the associative learning that enhanced methamphetamine-induced self-administration. Moreover, chemogenetic inactivation of the secondary visual cortex (V2) reduced the enhancement of the drug-taking induced by associative learning but did not alter sucrose-taking. Further fiber photometry of V2 neurons demonstrated that methamphetamine-associative learning elicits V2 neuron excitation, and sucrose-associative learning elicits V2 neuron inhibition. CONCLUSIONS: Therefore, this study reveals the neurobiological mechanism of V2 excitability underlying how associative learning participates in the formation of intractable memory related to drug addiction, and gives evidence to support V2 as a promising target for stimulation therapy for methamphetamine addiction.

8.
Cancer Lett ; 595: 216987, 2024 May 28.
Article in English | MEDLINE | ID: mdl-38815798

ABSTRACT

Triple-negative breast cancer (TNBC) is a highly lethal malignancy with limited therapy options. Aberrant metabolism, a key hallmark of human cancers, plays a crucial role in tumor progression, therapeutic responses and TNBC-related death. However, the underlying mechanisms are not fully understood. In this study, we delineate a previously unrecognized role of aberrant glucose metabolism in regulating the turnover of Snail1, which is a key transcriptional factor of epithelial-mesenchymal transition (EMT) and critically contributes to the acquisition of stemness, metastasis and chemo-resistance. Mechanistically, we demonstrate that AMP-activated protein kinase (AMPK), when activated in response to glucose deprivation, directly phosphorylates Snail1 at Ser11. Such a phosphorylation modification of Snail1 facilitates its recruitment of the E3 ligase FBXO11 and promotes its degradation, thereby suppressing stemness, metastasis and increasing cellular sensitivity to chemotherapies in vitro and in vivo. Clinically, histological analyses reveal a negative correlation between p-AMPKα and Snail1 in TNBC specimens. Taken together, our findings establish a novel mechanism and functional significance of AMPK in linking glucose status to Snail1-dependent malignancies and underscore the potential of AMPK agonists as a promising therapeutic strategy in the management of TNBC.

9.
Talanta ; 275: 126134, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-38692044

ABSTRACT

Phosphoenolpyruvate (PEP) is an essential intermediate metabolite that is involved in various vital biochemical reactions. However, achieving the direct and accurate quantification of PEP in plasma or serum poses a significant challenge owing to its strong polarity and metal affinity. In this study, a sensitive method for the direct determination of PEP in plasma and serum based on ethylenediaminetetraacetic acid (EDTA)-facilitated hydrophilic interaction liquid chromatography-tandem mass spectrometry was developed. Superior chromatographic retention and peak shapes were achieved using a zwitterionic stationary-phase HILIC column with a metal-inert inner surface. Efficient dechelation of PEP-metal complexes in serum/plasma samples was achieved through the introduction of EDTA, resulting in a significant enhancement of the PEP signal. A PEP isotopically labelled standard was employed as a surrogate analyte for the determination of endogenous PEP, and validation assessments proved the sensitivity, selectivity, and reproducibility of this method. The method was applied to the comparative quantification of PEP in plasma and serum samples from mice and rats, as well as in HepG2 cells, HEK293T cells, and erythrocytes; the results confirmed its applicability in PEP-related biomedical research. The developed method can quantify PEP in diverse biological matrices, providing a feasible opportunity to investigate the role of PEP in relevant biomedical research.


Subject(s)
Edetic Acid , Hydrophobic and Hydrophilic Interactions , Phosphoenolpyruvate , Tandem Mass Spectrometry , Tandem Mass Spectrometry/methods , Animals , Humans , Edetic Acid/chemistry , Mice , Chromatography, Liquid/methods , Rats , Phosphoenolpyruvate/chemistry , Phosphoenolpyruvate/blood , Phosphoenolpyruvate/metabolism , HEK293 Cells , Hep G2 Cells , Rats, Sprague-Dawley , Male
10.
Brain Res ; 1839: 148999, 2024 May 16.
Article in English | MEDLINE | ID: mdl-38761845

ABSTRACT

BACKGROUND: Microglia are damaged during cerebral ischemia-reperfusion (I/R). This study was performed to investigate the regulatory effect of tAR DNA-binding protein-43 (TDP-43) on microglia after cerebral I/R in vitro and in vivo. METHOD: The hypoxia/reoxygenation (H/R) treated microglia and rats with middle cerebral artery occlusion surgery were constructed respectively. The TDP-43 expression in brain tissues and microglia of each group was evaluated by qPCR and western blotting methods. Cell viability and cell apoptosis were combined to evaluate the degree of cell injury. As for animal experiments, neurological score and infarct volume were obtained to evaluate neurological injury. RESULTS: The levels of TDP-43 in the brain tissues of I/R group were higher than that in sham group. Both TDP-43 and Iba1, a typical microglia marker, were expressed in the brain tissues. TDP-43 was also elevated in microglia with H/R treatment. Inhibition of TDP-43 significantly down-regulated neurological deficit scores of rats after I/R surgery, and weakened the H/R treatment induced injury by promoting cell viability, inhibiting cell apoptosis, down-regulating IL-6 and iNOS levels, and up-regulating Arg-1 and IL-10 levels. Inactivation of cGAS pathway mediated by TDP-43 knockdown protects microglia from H/R treatment induced injury. CONCLUSION: The highly expressed TDP-43 level is associated with cerebral I/R, and inhibition of TDP-43 protects microglia from H/R induced injury through cGAS pathway in vitro and in vivo.

11.
Photodiagnosis Photodyn Ther ; 46: 104068, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38598961

ABSTRACT

Port-wine stain (PWS) birthmarks are congenital capillary malformations occurring in 0.3 %∼0.5 % of newborns. Hemoporfin-mediated vascular-acting photodynamic therapy (Hemoporfin PDT) is an emerging option for treating PWS. This in vivo study aimed to compare laser and light-emitting diodes (LED) as light source for Hemoporfin PDT. Chicken wattles were used as the animal model. Color and histopathological changes were evaluated after combining Hemoporfin with KTP laser or LED light source of 532 nm at the same doses. Both PDT approaches could induce significant vascular injury and color bleaching. Although the use of the laser resulted in a greater vascular clearance, the LED showed more uniform distribution both in the beam profiles and tissue reaction and exhibited better safety. This in vivo study suggests that the LED is a favorable choice for larger PWS lesion.


Subject(s)
Chickens , Hematoporphyrins , Photochemotherapy , Photosensitizing Agents , Port-Wine Stain , Animals , Port-Wine Stain/drug therapy , Photochemotherapy/methods , Photosensitizing Agents/pharmacology , Hematoporphyrins/pharmacology , Lasers, Solid-State/therapeutic use , Disease Models, Animal
12.
Chem Soc Rev ; 53(9): 4490-4606, 2024 May 07.
Article in English | MEDLINE | ID: mdl-38502087

ABSTRACT

Living organisms in nature have undergone continuous evolution over billions of years, resulting in the formation of high-performance fracture-resistant biomineralized tissues such as bones and teeth to fulfill mechanical and biological functions, despite the fact that most inorganic biominerals that constitute biomineralized tissues are weak and brittle. During the long-period evolution process, nature has evolved a number of highly effective and smart strategies to design chemical compositions and structures of biomineralized tissues to enable superior properties and to adapt to surrounding environments. Most biomineralized tissues have hierarchically ordered structures consisting of very small building blocks on the nanometer scale (nanoparticles, nanofibers or nanoflakes) to reduce the inherent weaknesses and brittleness of corresponding inorganic biominerals, to prevent crack initiation and propagation, and to allow high defect tolerance. The bioinspired principles derived from biomineralized tissues are indispensable for designing and constructing high-performance biomimetic materials. In recent years, a large number of high-performance biomimetic materials have been prepared based on these bioinspired principles with a large volume of literature covering this topic. Therefore, a timely and comprehensive review on this hot topic is highly important and contributes to the future development of this rapidly evolving research field. This review article aims to be comprehensive, authoritative, and critical with wide general interest to the science community, summarizing recent advances in revealing the formation processes, composition, and structures of biomineralized tissues, providing in-depth insights into guidelines derived from biomineralized tissues for the design and construction of high-performance biomimetic materials, and discussing recent progress, current research trends, key problems, future main research directions and challenges, and future perspectives in this exciting and rapidly evolving research field.


Subject(s)
Biomimetic Materials , Biomimetic Materials/chemistry , Biomimetic Materials/metabolism , Humans , Animals , Biomineralization , Bone and Bones/chemistry , Bone and Bones/metabolism , Biomimetics/methods , Tooth/chemistry
13.
Int J Biol Macromol ; 266(Pt 1): 131169, 2024 May.
Article in English | MEDLINE | ID: mdl-38554899

ABSTRACT

Autogenous bone transplantation is a prevalent clinical method for addressing bone defects. However, the limited availability of donor bone and the morbidity associated with bone harvesting have propelled the search for suitable bone substitutes. Bio-inspired scaffolds, particularly those fabricated using electron beam melting (EBM) deposition technology, have emerged as a significant advancement in this field. These 3D-printed titanium alloy scaffolds are celebrated for their outstanding biocompatibility and favorable elastic modulus. Thermosensitive chitosan hydrogel, which transitions from liquid to solid at body temperature, serves as a popular carrier in bone tissue engineering. Icariin (ICA), known for its efficacy in promoting osteoblast differentiation from bone marrow mesenchymal stem cells (BMSCs), plays a crucial role in this context. We developed a system combining a 3D-printed titanium alloy with a thermosensitive chitosan hydrogel, capable of local bone regeneration and integration through ICA delivery. Our in vitro findings reveal that this system can gradually release ICA, demonstrating excellent biocompatibility while fostering BMSC proliferation and osteogenic differentiation. Immunohistochemistry and Micro-CT analyses further confirm the effectiveness of the system in accelerating in vivo bone regeneration and enhancing osseointegration. This composite system lays a significant theoretical foundation for advancing local bone regeneration and integration.


Subject(s)
Alloys , Cell Differentiation , Chitosan , Flavonoids , Hydrogels , Mesenchymal Stem Cells , Osseointegration , Osteogenesis , Printing, Three-Dimensional , Tissue Scaffolds , Titanium , Chitosan/chemistry , Chitosan/pharmacology , Titanium/chemistry , Osseointegration/drug effects , Alloys/chemistry , Alloys/pharmacology , Tissue Scaffolds/chemistry , Animals , Mesenchymal Stem Cells/drug effects , Mesenchymal Stem Cells/cytology , Osteogenesis/drug effects , Hydrogels/chemistry , Hydrogels/pharmacology , Cell Differentiation/drug effects , Cell Proliferation/drug effects , Bone Regeneration/drug effects , Tissue Engineering/methods
14.
Medicine (Baltimore) ; 103(13): e37550, 2024 Mar 29.
Article in English | MEDLINE | ID: mdl-38552075

ABSTRACT

BACKGROUND: Current study aimed to investigate the clinical characterization, differential diagnosis, and treatment of splenic littoral cell angioma (LCA). METHODS: A retrospective analysis was performed for 10 LCA cases admitted to Huzhou Central Hospital from 2007 to 2023, for clinical manifestations, hematological tests, imaging features, pathological features, treatment methods, and prognosis along with the relevant literature was also reviewed. RESULTS: During examinations, no specific clinical manifestations and hematological abnormalities were seen in all 10 cases of LCA. Imaging observations depicted single or even multiple spherical lesions in the spleen. Plains shown by computed tomography (CT) were found somewhat equal or slightly lower in density. On the other hand, magnetic resonance imaging (MRI) plain scans viz. T1 weighted image showed equal low and mixed signals while T2-weighted showed high and low mixed signals. Moreover, punctate low signals could be seen in high signals named "freckle sign" in MRI scans. On contrast-enhanced CT scans, the enhancement of the lesions was not obvious in the arterial phase, and some of the lesions showed edged ring-like enhancements and "filling lake" progressive enhancement during the venous phase and delayed phase. In multiple lesions, the number of enhanced scan lesions showed a variable changing pattern "less-more-less." MRI-enhanced scan showed the characteristics of "fast in and slow out." Microscopic examinations identified tumor tissue actually composed of sinus-like lacunae that anastomosed with each other in the form of a network. Furthermore, cystic expansion and pseudopapillary protrusions were also seen in the dilated sinus cavity which was lined with single-layer endothelial cells having conspicuous cytoplasmic hemosiderin. High immunophenotypic expressions of vascular endothelial cell phenotype (CD31, CD34, FVIII) and tissue cell phenotype (CD68) were also seen. Total and partial splenectomy were performed in 8 and 2 patients, respectively, and follow-up examinations showed survival in all patients with no recurrence. CONCLUSION: LCA is a rare splenic benign lesion with atypical clinical manifestations. CT and MRI imaging are important tools in preoperative diagnosis based on pathomorphological and immunohistochemical examinations. Splenectomy is a superior therapeutic choice with significant impacts and prognosis.


Subject(s)
Endothelial Cells , Hemangioma , Splenic Neoplasms , Humans , Endothelial Cells/pathology , Retrospective Studies , Splenic Neoplasms/diagnostic imaging , Splenic Neoplasms/surgery
15.
Neurosci Res ; 2024 Feb 15.
Article in English | MEDLINE | ID: mdl-38364907

ABSTRACT

Although the brain can discriminate between various sweet substances, the underlying neural mechanisms of this complex behavior remain elusive. This study examines the role of the anterior paraventricular nucleus of the thalamus (aPVT) in governing sweet preference in mice. We fed the mice six different diets with equal sweetness for six weeks: control diet (CD), high sucrose diet (HSD), high stevioside diet (HSSD), high xylitol diet (HXD), high glycyrrhizin diet (HGD), and high mogroside diet (HMD). The mice exhibited a marked preference specifically for the HSD and HSSD. Following consumption of these diets, c-Fos expression levels in the aPVT were significantly higher in these two groups compared to the others. Utilizing fiber photometry calcium imaging, we observed rapid activation of aPVT neurons in response to sucrose and stevioside intake, but not to xylitol or water. Our findings suggest that aPVT activity aligns with sweet preference in mice, and notably, stevioside is the sole plant-based sweetener that elicits an aPVT response comparable to that of sucrose.

16.
Gynecol Oncol ; 185: 58-67, 2024 Feb 17.
Article in English | MEDLINE | ID: mdl-38368814

ABSTRACT

OBJECTIVE: Adenoid cystic carcinoma (AdCC) of the Bartholin's gland (AdCC-BG) is a very rare gynecologic vulvar malignancy. AdCC-BGs are slow-growing but locally aggressive and are associated with high recurrence rates. Here we sought to characterize the molecular underpinning of AdCC-BGs. METHODS: AdCC-BGs (n = 6) were subjected to a combination of RNA-sequencing, targeted DNA-sequencing, reverse-transcription PCR, fluorescence in situ hybridization (FISH) and MYB immunohistochemistry (IHC). Clinicopathologic variables, somatic mutations, copy number alterations and chimeric transcripts were assessed. RESULTS: All six AdCC-BGs were biphasic, composed of ductal and myoepithelial cells. Akin to salivary gland and breast AdCCs, three AdCC-BGs had the MYB::NFIB fusion gene with varying breakpoints, all of which were associated with MYB overexpression by IHC. Two AdCC-BGs were underpinned by MYBL1 fusion genes with different gene partners, including MYBL1::RAD51B and MYBL1::EWSR1 gene fusions, and showed MYB protein expression. Although the final AdCC-BG studied had MYB protein overexpression, no gene fusion was identified. AdCC-BGs harbored few additional somatic genetic alterations, and only few mutations in cancer-related genes were identified, including GNAQ, GNAS, KDM6A, AKT1 and BCL2, none of which were recurrent. Two AdCC-BGs, both with a MYB::NFIB fusion gene, developed metastatic disease. CONCLUSIONS: AdCC-BGs constitute a convergent phenotype, whereby activation of MYB or MYBL1 can be driven by the MYB::NFIB fusion gene or MYBL1 rearrangements. Our observations further support the notion that AdCCs, irrespective of organ site, constitute a genotypic-phenotypic correlation. Assessment of MYB or MYBL1 rearrangements may be used as an ancillary marker for the diagnosis of AdCC-BGs.

17.
Plants (Basel) ; 13(2)2024 Jan 14.
Article in English | MEDLINE | ID: mdl-38256784

ABSTRACT

Oxidosqualene cyclases (OSCs) are the key enzymes accountable for the cyclization of 2,3-oxidosqualene to varied triterpenoids and phytosterols. Hoodia gordonii (from the family Apocynaceae), a native of the Kalahari deserts of South Africa, Namibia, and Botswana, is being sold as a prevalent herbal supplement for weight loss. The appetite suppressant properties are attributed to P57AS3, an oxypregnane steroidal glycoside. At the molecular level, the enzymes involved in the biosynthesis of triterpenes and phytosterols from H. gordonii have not been previously reported. In the current study, predicted transcripts potentially encoding oxidosqualene cyclases were recognized first by searching publicly available H. gordonii RNA-seq datasets. Two OSC-like sequences were selected for functional analysis. A monofunctional OSC, designated HgOSC1 which encodes lupeol synthase, and HgOSC2, a multifunctional cycloartenol synthase forming cycloartenol and other products, were observed through recombinant enzyme studies. These studies revealed that distinct OSCs exist for triterpene formation in H. gordonii and provided opportunities for the metabolic engineering of specific precursors in producing phytosterols in this plant species.

18.
J Colloid Interface Sci ; 660: 370-380, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38244503

ABSTRACT

Solar energy-driven water evaporation technology is a promising, low-cost and sustainable approach to alleviate the global clean water shortage, but usually suffers from low water evaporation rate and severe salt deposition on the water evaporation surface. In this work, a hydrophilic bilayer photothermal paper-based three-dimensional (3D) cone flowing evaporator was designed and prepared for stable high-performance seawater desalination with excellent salt-rejecting ability. The as-prepared bilayer photothermal paper consisted of MXene (Ti3C2Tx) and HAA (ultralong hydroxyapatite nanowires, poly(acrylic acid), and poly(acrylic acid-2-hydroxyethyl ester)). The accordion-like multilayered MXene acted as the efficient solar light absorber, and ultralong hydroxyapatite (HAP) nanowires served as the thermally insulating and supporting skeleton with a porous networked structure. A siphon effect-driven unidirectional fluid transportation unit in the 3D cone flowing evaporator could guide the concentrated saline flowing away from the evaporating surface to prevent salt deposition on the evaporation surface, avoiding severe deterioration of the performance in solar water evaporation. Furthermore, combining high solar light absorption and high photothermal conversion efficiencies, low water evaporation enthalpy (1838 ±â€¯11 J g-1), and additional energy taken from the ambient environment, the as-prepared cone flowing evaporator exhibited a high water evaporation rate of 3.22 ±â€¯0.20 kg m-2 h-1 for real seawater under one sun illumination (1 kW m-2), which was significantly higher than many values reported in the literature. This study provides an effective approach for designing high-performance solar energy-driven water evaporators for sustainable seawater desalination and wastewater purification.

19.
Curr Biol ; 34(2): 389-402.e5, 2024 01 22.
Article in English | MEDLINE | ID: mdl-38215742

ABSTRACT

Aversive stimuli activate corticotropin-releasing factor (CRF)-expressing neurons in the paraventricular nucleus of hypothalamus (PVNCRF neurons) and other brain stress systems to facilitate avoidance behaviors. Appetitive stimuli also engage the brain stress systems, but their contributions to reward-related behaviors are less well understood. Here, we show that mice work vigorously to optically activate PVNCRF neurons in an operant chamber, indicating a reinforcing nature of these neurons. The reinforcing property of these neurons is not mediated by activation of the hypothalamic-pituitary-adrenal (HPA) axis. We found that PVNCRF neurons send direct projections to the ventral tegmental area (VTA), and selective activation of these projections induced robust self-stimulation behaviors, without activation of the HPA axis. Similar to the PVNCRF cell bodies, self-stimulation of PVNCRF-VTA projection was dramatically attenuated by systemic pretreatment of CRF receptor 1 or dopamine D1 receptor (D1R) antagonist and augmented by corticosterone synthesis inhibitor metyrapone, but not altered by dopamine D2 receptor (D2R) antagonist. Furthermore, we found that activation of PVNCRF-VTA projections increased c-Fos expression in the VTA dopamine neurons and rapidly triggered dopamine release in the nucleus accumbens (NAc), and microinfusion of D1R or D2R antagonist into the NAc decreased the self-stimulation of these projections. Together, our findings reveal an unappreciated role of PVNCRF neurons and their VTA projections in driving reward-related behaviors, independent of their core neuroendocrine functions. As activation of PVNCRF neurons is the final common path for many stress systems, our study suggests a novel mechanism underlying the positive reinforcing effect of stressful stimuli.


Subject(s)
Corticotropin-Releasing Hormone , Pituitary Hormone-Releasing Hormones , Mice , Animals , Corticotropin-Releasing Hormone/metabolism , Pituitary Hormone-Releasing Hormones/metabolism , Pituitary Hormone-Releasing Hormones/pharmacology , Hypothalamo-Hypophyseal System , Pituitary-Adrenal System , Hypothalamus/metabolism , Paraventricular Hypothalamic Nucleus/metabolism , Dopaminergic Neurons/metabolism
20.
Molecules ; 29(2)2024 Jan 22.
Article in English | MEDLINE | ID: mdl-38276628

ABSTRACT

Ultralong nanowires with ultrahigh aspect ratios exhibit high flexibility, and they are promising for applications in various fields. Herein, a cadmium oleate precursor hydrothermal method is developed for the synthesis of ultralong nanowires of cadmium phosphate hydroxide. In this method, water-soluble cadmium salt is used as the cadmium source, water-soluble phosphate is used as the phosphorus source, and sodium oleate is adopted as a reactant to form cadmium oleate precursor and as a structure-directing agent. By using this method, ultralong nanowires of cadmium phosphate hydroxide are successfully synthesized using CdCl2, sodium oleate, and NaH2PO4 as reactants in an aqueous solution by hydrothermal treatment at 180 °C for 24 h. In addition, a new type of flexible fire-resistant inorganic paper with good electrical insulation performance is fabricated using ultralong nanowires of cadmium phosphate hydroxide. As an example of the extended application of this synthetic method, ultralong nanowires of cadmium phosphate hydroxide can be converted to ultralong CdS nanowires through a convenient sulfidation reaction. In this way, ultralong CdS nanowires are successfully synthesized by simple sulfidation of ultralong nanowires of cadmium phosphate hydroxide under mild conditions. The as-prepared ultralong nanowires of cadmium phosphate hydroxide are promising for applications as the precursors and templates for synthesizing other inorganic ultralong nanowires and have wide applications in various fields.

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