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(1) Background: Climate change significantly impacts the phenology and dynamics of radial tree growth in alpine dryland forests. However, there remains a scarcity of reliable information on the physiological processes of tree growth and cambial phenology in response to long-term climate change in cold and semi-arid regions. (2) Methods: We employed the process-based Vaganov–Shashkin (VS) model to simulate the phenology and growth patterns of Chinese pine (Pinus tabuliformis) in the eastern Qilian Mountains, northeastern Tibetan Plateau. The model was informed by observed temperature and precipitation data to elucidate the relationships between climate factors and tree growth. (3) Results: The simulated tree-ring index closely aligned with the observed tree-ring chronology, validating the VS model's effectiveness in capturing the climatic influences on radial growth and cambial phenology of P. tabuliformis. The model outputs revealed that the average growing season spanned from mid-April to mid-October and experienced an extension post-1978 due to ongoing warming trends. However, it is important to note that an increase in the duration of the growing season did not necessarily result in a higher level of radial growth. (4) Conclusions: While the duration of the growing season was primarily determined by temperature, the growth rate was predominantly influenced by water conditions during the growing season, making it the most significant factor contributing to ring formation. Our study provides valuable insights into the potential mechanisms underlying tree growth responses to climate change in cold and semi-arid regions. [ABSTRACT FROM AUTHOR]

This letter to the editor discusses the case of a 58-year-old man with Acute Wernicke Encephalopathy who underwent PET/CT imaging. The imaging revealed increased uptake in the midbrain, medial thalamus, and periaqueductal gray matter, which contrasts with previously reported decreased uptake associated with Wernicke encephalopathy. Treatment with vitamin B1 injection resulted in clinical improvement, and follow-up imaging showed decreased FDG uptake in the cerebral lesion areas. The study suggests that PET/CT can reflect glucose metabolism changes in vital organs affected by thiamine deficiency in Acute Wernicke's encephalopathy. [Extracted from the article]

Quantifying the strength of the ecogeographic barrier is an important aspect of plant speciation research, and serves as a practical step to understanding the evolutionary trajectory of plants under climate change. Here, we quantified the extent of ecogeographic isolation in four closely related Aquilegia species that radiated in the Mountains of SW China and adjacent regions, often lacking intrinsic barriers. We used environmental niche models to predict past, present, and future species potential distributions and compared them to determine the degree of overlap and ecogeographic isolation. Our investigation found significant ecological differentiation in all studied species pairs except A. kansuensis and A. ecalacarata. The current strengths of ecogeographic isolation are above 0.5 in most cases. Compared with current climates, most species had an expanding range in the Last Glacial Maximum, the Mid Holocene, and under four future climate scenarios. Our results suggested that ecogeographic isolation contributes to the diversification and maintenance of Aquilegia species in the Mountains of northern and SW China and would act as an essential reproductive barrier in the future. [ABSTRACT FROM AUTHOR]

Novel strategies for diagnosing triple-negative breast cancer (TNBC) are essential for effective clinical treatment. Vascular endothelial growth factor receptor 2 (VEGFR2) and neuropilin-1 (NRP-1) are potential targets for tumor imaging agents. We designed and synthesized [99mTc]Tc-labeled heptapeptide (A7R) and its D-type peptide (DA7R) with high affinity and specificity for VEGFR2 and NRP-1 as novel single-photon emission computed tomography (SPECT) probes for TNBC imaging. The specificities of A7R and DA7R were first evaluated in vitro using flow cytometry and confocal microscopy and ex vivo using fluorescence imaging. Subsequently, A7R and DA7R were labeled with [99mTc]Tc through 6-hydrazino nicotinamide (HYNIC), and their radiochemical purities (RCPs) and stability in vitro were assessed. The imaging performance and biodistribution of [99mTc]Tc-HYNIC-A7R and [99mTc]Tc-HYNIC-DA7R were evaluated in TNBC mouse models. A7R and DA7R exhibited good TNBC cell-targeting abilities and were readily labeled with [99mTc]Tc through HYNIC. Both [99mTc]Tc-HYNIC-A7R and [99mTc]Tc-HYNIC-DA7R had high RCPs and stability in vitro, and their accumulation in tumor tissues in the TNBC models was evident, with fast blood clearance and favorable biodistribution. More importantly, [99mTc]Tc-HYNIC-DA7R showed better tumor-to-muscle ratios and lower renal uptake than [99mTc]Tc-HYNIC-A7R. These results suggest that both [99mTc]Tc-HYNIC-DA7R and [99mTc]Tc-HYNIC-A7R have substantial potential as probes for targeted SPECT imaging of TNBC, and the former may be considered for future clinical translation owing to its superior tumor imaging performance. [ABSTRACT FROM AUTHOR]

Certain receptors are often overexpressed during tumor occurrence and development and closely correlate with carcinogenesis. Owing to its overexpression on the cell membrane and cytoplasm of various tumors, plectin, which is involved in tumor proliferation, migration, and invasion, has been viewed as a promising target for cancer imaging. Hence, plectin-targeting agents have great potential as imaging probes for tumor diagnosis. In this study, we developed a [99mTc]Tc-labeled plectin-targeted peptide (PTP) as a novel single-photon emission computed tomography (SPECT) probe for tumor imaging and investigated its pharmacokinetics, biodistribution, and targeting ability in several types of tumor-bearing mouse models. The PTP had good biocompatibility and targeting ability to tumor cells in vitro and could be readily labeled with [99mTc]Tc after modification with the bifunctional chelator 6-hydrazino nicotinamide (HYNIC). Furthermore, the prepared [99mTc]Tc-labeled PTP ([99mTc]Tc-HYNIC-PTP) showed high radiochemical purity and excellent stability in vitro. In addition, favorable biodistribution, fast blood clearance, and clear accumulation of [99mTc]Tc-HYNIC-PTP in several types of tumors were observed, with a good correlation between tumor uptake and plectin expression levels. These results indicate the potential of [99mTc]Tc-HYNIC-PTP as a novel SPECT probe for tumor imaging. [ABSTRACT FROM AUTHOR]

This study was to investigate the synthesis and biological evaluation of [99mTc]Tc-labeled Buthus martensii Karsch Chlorotoxin ([99mTc]Tc-BmK CT) as a radiopharmaceutical for glioma single photon computed emission tomography (SPECT) imaging. The results showed that BmK CT peptide modified with a hexahistidine tag displayed good cytocompatibility in vitro, and could be efficiently radiolabeled with 99mTc via [99mTc]Tc-tricarbonyl chemistry. The [99mTc]Tc-BmK CT showed satisfactory radiochemical purity and stability in vitro, and could be developed as a probe for targeted SPECT imaging of glioma cells in vitro and in a tumor-bearing mouse model. Our data indicated that the synthesized [99mTc]Tc-BmK CT might be developed as a promising imaging agent for glioma diagnostic application. [ABSTRACT FROM AUTHOR]

An increasing number of studies show the diagnostic and therapeutic potential of scorpion venoms and toxins in cancer, including malignant glioma that represents the most fatal primary brain tumors. Chlorotoxin (CTX) and a CTX-like peptide Buthus martensii Karsch chlorotoxin (BmK CT) derived from scorpion venoms, have been identified as glioma-specific agents for imaging and therapy. In this study, we designed and manufactured a new BmK CT derivative (BmK CT-D) according to the amino acid sequences of native CTX and BmK CT and investigated the possibility of 99mTc-labeled BmK CT-D as a single-positron emission computed tomography (SPECT) imaging agent for glioma diagnosis. The data indicated that the BmK CT-D peptide had good cytocompatibility, improved cellular uptake compared to BmK CT, and could be readily radiolabeled by 99mTc via99mTc-tricarbonyl chemistry with high radiochemical yield and stability in vitro. Moreover, the formed 99mTc-BmK CT-D was able to be used as a probe for SPECT imaging of glioma cells in vitro and in tumor-bearing mice in vivo, indicating that the designed peptide is a promising targeting agent for tumor imaging. [ABSTRACT FROM AUTHOR]

PET/CT has been identified as one of the routine methods for the assessment of multiple myeloma (MM) bone marrow infiltration. In the routine method of performing PET/CT, the 18F-Fludeoxyglucose (18F-FDG) uptake in this disease is often used in the assessment of this condition, however CT diagnosis is not currently commonly used. The aim of the present study was to investigate the importance of CT in PET/CT for assessing diffuse infiltration (DI) of bone marrow in MM. MRI was used as a control in the present study, which is the gold standard for assessing DI of bone marrow and is divided into 3 levels: Mild, moderate and severe DI. Subsequently, a total of four combinations of PET and CT results were listed using the enumeration method for the evaluation of DI in the bone marrow. These combinations were respectively compared with the three levels of MR imaging to screen the most consistent method. The concordances of the new method and routine 18F-FDG PET/CT for the assessment of DI with MR imaging were compared using the McNemar test, respectively. The results of the DI assessment from the two methods were verified by performing Durie-Salmon (D-S) PLUS staging. Compared with MR imaging, the results were as follows: PET and CT exhibited negative results, suggesting mild DI; one of them was positive, suggesting moderate DI; and two were positive, suggesting severe DI. The results of concordance between two methods (new and routine) and MR imaging are indicated as follows: For the new method, McNemar test, P=0.513 and Kappa=0.745; for the routine 18F-FDG PET/CT method, McNemar test, P=0.03 and Kappa=0.547. Re-performance of D-S PLUS staging presented the following results: New method, McNemar test, P=0.317 and Kappa=0.93; for the routine method, McNemar test, P=0.223 and Kappa=0.811. These findings indicated that the CT component of PET/CT could improve the concordance with MRI results in the assessment of DI, and the same results were obtained when D-S PLUS staging was performed. The CT in PET/CT can enhance diagnostic accuracy in the assessment of DI by reducing the false negatives when compared with the routine 18F-FDG method. [ABSTRACT FROM AUTHOR]

Background:In addition to being a food source, flowers provide non-obvious rewards to their pollinators, such as heat or shelter. However, these rewards have seldom been studied. Aims:Plant–pollinator interactions between an alpine plantCodonopsis convolvulaceaand its main pollinator, a bee (Andrenasp.) were characterised. Methods:We recorded the floral biology and floral visitors in three populations ofCodonopsis. Pollination treatments were conducted to evaluate the importance of insect visitors. Results:The bee was the only visitor to two populations, and the main visitor to a third population. Females visited flowers to collect pollen, while males had a multi-faceted relationship with flowers. Nectar was the food resource of males. When the air temperature was <18 °C, they slept on flowers. During the day flowers were bowl-shaped solar collectors (1–3 °C warmer than the ambient air), and flowers were closed at night. Copulation was occasionally observed on flowers. Although flowers lasted 2 days and males were active for 3 h per day, the high visiting frequency (19.8 per flower per hour) guaranteed pollination of each flower. Conclusions:We suggest that the combination of multiple rewards protect males from cold and unstable weather conditions and encourage them to visit more flowers, and that the specialised pollination system is promoted by the harsh alpine environment. [ABSTRACT FROM AUTHOR]

Myocardial ischemia-reperfusion (IR) injury is a critical complication following revascularization therapy for ischemic heart disease. Itaconate, a macrophage-derived metabolite, has been implicated in inflammation and metabolic regulation. This study investigates the protective role of itaconate derivatives against IR injury. Using a mice model of IR injury, the impact of 7-day 4-Octyl itaconate (4-OI) administration on cardiac function is assessed. Exogenous administration of 4-OI significantly reduces myocardial damage, enhances angiogenesis, and alleviates myocardial hypoxia injury during reperfusion. RNA sequencing and molecular docking techniques are used to find the target of itaconate, and changes in cardiac function are observed in Immune-Responsive Gene1 (IRG1) global knockout mice. In cell culture studies, 4-OI promotes endothelial cell proliferation and migration, mediated by Mitogen-Activated Protein Kinases (MAPK) signaling pathway activation, particularly through Extracellular Signal-Regulated Kinase (ERK) signaling. Inhibition of ERK blocks these beneficial effects on endothelial cells. Furthermore, itaconate synthesis inhibition worsens myocardial damage, which is mitigated by 4-OI supplementation. The results indicate that 4-OI promotes angiogenesis by activating MAPK signaling via FMS-like tyrosine kinase 1 (Flt1), highlighting its potential as a therapeutic strategy for myocardial IR injury., (© 2025 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

Dystrophin is a critical interacting protein of Nav1.5 that determines its membrane anchoring in cardiomyocytes. Long noncoding RNAs (lncRNAs) are involved in the regulation of cardiac ion channels, while their influence on sodium channels remains unexplored. Our preliminary data showed that lncRNA- Dachshund homolog 1 ( lncDach1 ) can bind to dystrophin, which drove us to investigate if lncDach1 can regulate sodium channels by interfering with dystrophin. Western blot and immunofluorescent staining showed that cardiomyocyte-specific transgenic overexpression of lncDach1 ( lncDach1 -TG) reduced the membrane distribution of dystrophin and Nav1.5 in cardiomyocytes. Meanwhile, peak I Na was reduced in the hearts of lncDach1 -TG mice than wild-type (WT) controls. The opposite data of western blot, immunofluorescent staining and patch clamp were collected from lncDach1 cardiomyocyte conditional knockout ( lncDach1 -cKO) mice. Moreover, increased ventricular arrhythmia susceptibility was observed in lncDach1 -TG mice in vivo and ex vivo. The conservative fragment of lncDach1 inhibited membrane distribution of dystrophin and Nav1.5, and promoted the inducibility of ventricular arrhythmia. Strikingly, activation of Dystrophin transcription by dCas9-SAM system in lncDach1 -TG mice rescued the impaired membrane distribution of dystrophin and Nav1.5, and prevented the occurrence of ventricular arrhythmia. Furthermore, lncDach1 was increased in transaortic constriction (TAC) induced failing hearts, which promoted the inducibility of ventricular arrhythmia. And the expression of lncDach1 is regulated by hydroxyacyl-CoA dehydrogenase subunit beta (hadhb), which binds to lncDach1 and decreases its stability. The human homologue of lncDACH1 inhibited the membrane distribution of Nav1.5 in human iPS-differentiated cardiomyocytes. The findings provide novel insights into the mechanism of Nav1.5 membrane targeting and the development of ventricular arrhythmias., Competing Interests: GX, JY, YZ, YY, RZ, DL, TT, JL, XZ, CL, XL, JY, KS, YG, XL, GY, LX, HS, YL, YB, ZP No competing interests declared, (© 2023, Xue, Yang, Zhang et al.)

Purpose of the Report: To explore the value of 18 F-labeled prostate-specific membrane antigen (PSMA-1007) positron emission tomography (PET)/computed tomography (CT), the maximum standardized uptake value (SUVmax) of the primary tumor, prostate PSMA-tumor volume (PSMA-TVp), and prostate total lesion PSMA (TL-PSMAp) for predicting prostate cancer (PCa) metastasis and follow-up evaluation in primary PCa lesions., Materials and Methods: 18 F-PSMA-1007 PET/CT data of 110 consecutive newly diagnosed PCa patients were retrospectively analyzed. Patients were divided into non-metastatic, oligometastatic, and extensive metastatic groups. The predictive power was assessed using the receiver operating characteristic curve. Multi-group one-way analysis of variance and post-hoc tests were used to compare the groups. Patients were monitored post-therapy to evaluate treatment effectiveness., Results: Among the 110 patients, 66.4% (73) had metastasis (29 oligometastatic, 44 extensive metastasis). AUCs for Gleason score (GS), total prostate-specific antigen(TPSA), SUVmax, TL-PSMAp, and PSMA-TVp were 0.851, 0.916, 0.834, 0.938, and 0.923, respectively. GS, TPSA, SUVmax, TL-PSMAp, and PSMA-TVp were significantly different among the groups. In the post-hoc tests, differences in GS, TPSA, SUVmax, TL-PSMAp, and PSMA-TVp between the non-metastatic and oligometastatic groups and non-metastatic and extensive metastatic groups were significant (P<0.010). Differences in TL-PSMAp and PSMA-TVp between oligometastatic and extensive metastatic groups were significant (P=0.039 and 0.015, respectively), while those among GS, TPSA, and SUVmax were not. TL-PSMAp and PSMA-TVp distinguished between oligometastatic and extensive metastases, but GS, TPSA, and SUVmax did not. In individuals with oligometastasis, the implementation of active treatment for both primary and metastatic lesions may result in a more favorable prognosis., Conclusions: 18 F-PSMA-1007 PET/CT volumetric parameters PSMA-TVp and TL-PSMAp can predict PCa oligometastasis., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Li, Chen, Wang, Yang, Yang, Zhao and Li.)

Triple-negative breast cancer (TNBC) is the most aggressive breast cancer subtype, with a high mortality rate. One of the main reasons for this poor prognosis is the failure of a specific diagnosis. As a tumor-homing and penetrating peptide, iRGD has not only the properties of binding to neuropilin-1 and integrin αvβ3 but also internalizing into TNBC cells. In this study, we designed and prepared 99m Tc-labeled iRGD ( 99m Tc-HYNIC-iRGD) as a single-positron emission computed tomography (SPECT) imaging probe and investigated its feasibility for the targeted diagnosis of TNBC. The results showed that the iRGD peptide had acceptable biocompatibility within the studied concentration range and could specifically bind to TNBC cells in vitro . The 99m Tc-HYNIC-iRGD was readily prepared with high radiochemical purity and stability. SPECT imaging of 99m Tc-HYNIC-iRGD in a TNBC tumor-bearing mouse model showed obvious tumor accumulation with rapid blood clearance and favorable biodistribution. Our findings indicate that this active-targeted strategy has great potential to be developed as a novel tool for TNBC imaging., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Yu, Su, Zhao, Yang, Zhu and Zhao.)

Introduction: Smart theranostic nanosystems own a favorable potential to improve internalization within tumor while avoiding nonspecific interaction with normal tissues. However, development of this type of theranostic nanosystems is still a challenge., Methods: In this study, we developed the iodine-131 ( 131 I)-labeled multifunctional polyethylenimine (PEI)/doxorubicin (DOX) complexes with pH-controlled cellular uptake property for enhanced single-photon emission computed tomography (SPECT) imaging and chemo/radiotherapy of tumors. Alkoxyphenyl acylsulfonamide (APAS), a typical functional group that could achieve improved cellular uptake of its modified nanoparticles, was utilized to conjugate onto the functional PEI pre-modified with polyethylene glycol (PEG) with terminal groups of monomethyl ether and N-hydroxysuccinimide (mPEG-NHS), PEG with terminal groups of maleimide and succinimidyl valerate (MAL-PEG-SVA) through sulfydryl of APAS and MAL moiety of MAL-PEG-SVA. This was followed by conjugation with 3-(4'-hydroxyphenyl)propionic acid-OSu (HPAO), acetylating leftover amines of PEI, complexing DOX and labeling 131 I to generate the theranostic nanosystems., Results: The synthesized theranostic nanosystems exhibit favorable water solubility and stability. Every functional PEI can complex approximately 12.4 DOX, which could sustainably release of DOX following a pH-dependent manner. Remarkably, due to the surface modification of APAS, the constructed theranostic nanosystems own the capacity to achieve pH-responsive charge conversion and further lead to improved cellular uptake in cancer cells under slightly acidic condition. Above all, based on the coexistence of DOX and radioactive 131 I in the single nanosystem, the synthesized nanohybrid system could afford enhanced SPECT imaging and chemo/radioactive combination therapy of cancer cells in vitro and xenografted tumor model in vivo., Discussion: The developed smart nanohybrid system provides a novel strategy to improve the tumor theranostic efficiency and may be applied for different types of cancer., Competing Interests: The authors declare no conflicts of interest in this work., (© 2021 Zhu et al.)