bluuebunny/crossref_metadata_2025 huggingface dataset:
Trichomonad Gastritis in Rhesus Macaques (Macaca mulatta) Infected with Simian Immunodeficiency Virus
Authors: Kondova I. , Simon M. A. , Klumpp S. A. , MacKey J. , Widmer G. , Domingues H. G. , Persengiev S. P. , O'Neil S. P.
Published: January 2005

In a retrospective study, 51 cases of gastritis (14%) were identified from among 341 necropsies performed on simian immunodeficiency virus (SlV)-infected rhesus macaques ( Macaca mulatta) at the New England Primate Research Center from 1993 to 2001. Protozoa were seen in the stomach of 13 monkeys (25%) with gastritis. Two histopathologic manifestations of gastritis were observed: seven cases of lymphoplasmacytic gastritis with trichomonad trophozoites within lumens of gastric glands and four cases of necrosuppurative gastritis containing intralesional periodic acid-Schiff-positive protozoa; two cases of gastritis had morphologic features of both types of gastritis. In instances of necrosuppurative and combined lymphoplasmacytic and necrosuppurative gastritis, protozoa were 4-35 μm in diameter and round to tear-shaped. Because of the unusual morphology of the protozoa in these latter cases, transmission electron microscopy and polymerase chain reaction (PCR) were used to further identify these organisms. The protozoa were definitively identified as Tritrichomonas in all cases on the basis of ultrastructural characteristics (flagella and undulating membranes) and amplification of a 347-bp product of the 5.8S ribosomal RNA gene of Tritrichomonas foetus, Tritrichomonas suis and Tritrichomonas mobilensis by PCR using DNA extracted from stomach tissue. On the basis of these observations, we conclude that Tritrichomonas can be a significant cofactor in the development of necrosup-purative gastritis in SIV-infected rhesus macaques.
Overexpression of HER-2 in Feline Invasive Mammary Carcinomas: An Immunohistochemical Survey and Evaluation of Its Prognostic Potential
Authors: Millanta F. , Calandrella M. , Citi S. , Della Santa D. , Poli A.
Published: January 2005

The role of c-erbB-2 protooncogene status in feline invasive mammary carcinomas (FMCs) was assessed through the HER-2 receptor immunohistochemical expression. The HER-2 overexpression was then correlated with some relevant histologic parameters and with the clinical course of the disease during a 2-year follow-up. Forty-seven FMCs from surgically treated queens were considered. Tumors were classified according to the WHO criteria and stromal or lymphatic invasion (or both) and histologic grading were recorded. The immunohistochemical staining was performed on paraffin sections and a well-defined scoring system based upon numbers of HER-2 receptors expressed on the cell surface was applied according to standard guidelines. Overall survival (OS) distributions were generated with the Kaplan-Meier method. HER-2 overexpression was detected in 28 of the 47 carcinomas (59.6%). This parameter was demonstrated to be significantly correlated with the shorter OS ( P = 0.02). However, the HER-2 overexpression did not show significant correlation with histologic type, tumor grading, or presence of lymphatic invasion. Furthermore, the HER-2 overexpression appeared with a higher percentage in FMCs than what is reported in canine or human mammary carcinomas. The significant correlation with a shorter OS suggests a possible role of HER-2 as an additional marker of malignancy in FMCs and as a reliable prognostic indicator As in the human oncology practice, the identification of the FMCs that overexpress HER-2 may also promote new therapeutic strategies.
Comparison of Diagnostic Detection Methods for Mycobacterium avium subsp. paratuberculosis in North American Bison
Authors: Huntley J. F. J. , Whitlock R. H. , Bannantine J. P. , Stabel J. R.
Published: January 2005

Tissues and fecal material were collected from 14 North American bison ( Bison bison) that were suspected of having Johne's disease and analyzed for the presence of Mycobacterium avium subsp. paratuberculosis (M. paratuberculosis). Sections of ileum, ileal-cecal lymph node, and three sequential sections of jejunum with their associated mesenteric lymph nodes were taken from each animal. Fecal culture indicated that 5 of 14 (35.7%) animals were infected, whereas cultures from tissues detected 12 of 14 (85.7%) animals as infected and 59 of 111 (53.2%) of the tissues as positive for M. paratuberculosis. Polymerase chain reaction analysis identified infection in 14 of 14 (100%) animals and in 91 of 112 (81.2%) tissues. In addition, tissues were processed for Ziehl-Neelsen acid-fast staining, auramine O/acridine orange fluorescent staining, and immunohistochemical staining. Ziehl-Neelsen and auramine O staining identified 7 of 14 (50%) and 5 of 14 (35.7%) animals as infected and 24 of 112 (21.4%) and 28 of 112 (25%) tissues as positive, respectively. Immunohistochemical analyses of bison tissues, using antisera collected from rabbits immunized with four different preparations of M. paratuberculosis, identified a greater percentage of infected animals (ranging from 57 to 93%) and positive tissues (ranging from 28 to 46%). Collectively, these data indicate that DNA-based detection of M. paratuberculosis was more sensitive than bacterial culture or staining, identified infection in all the bison, and detected the greatest number of positive tissues within each animal.
Systemic AL Amyloidosis Associated with Multiple Myeloma in a Horse
Authors: Kim D. Y. , Taylor H. W. , Eades S. C. , Cho D.-Y.
Published: January 2005

AL amyloidosis is the most common type of systemic amyloidosis in humans, and it is frequently associated with multiple myeloma. But, AL amyloidosis is very rare in domestic animals. A 16-year-old Quarter horse gelding was diagnosed with systemic AL amyloidosis associated with multiple myeloma. Clinical problems were rapid weight loss, muscle atrophy, soft unformed stool, and ventral edema. Grossly, diffuse gastrointestinal hemorrhage, markedly thickened jejunal mucosa, and splenomegaly were present. Microscopically, diffuse severe amyloid deposits were present in the lamina propria of glandular stomach, duodenum, and jejunum. Much of the spleen and sternal bone marrow was replaced by neoplastic round cells, and multiple foci of amyloid were also present in the spleen and bone marrow. Electron microscopy revealed the neoplastic round cells to be of plasma cell origin, and the amyloid showed a strongly positive immunoreactivity with polyclonal anti-human immunoglobin lambda light-chain antisera. To our knowledge, this is the second report describing systemic AL amyloidosis in domestic animals-associated plasma cell neoplasia and the first associated with multiple myeloma, as is common in humans.
Thyroid Carcinosarcoma in a Dog
Authors: Grubor B. , Haynes J. S.
Published: January 2005

An adult male mixed breed dog developed pain, on swallowing, that lasted for 1 week. Physical exam and radiographs revealed a subcutaneous mass in the cervical area and three metastatic nodules in the lung. The cervical mass was surgically removed and fixed in 10% buffered formalin. Histopathologic diagnosis was carcinosarcoma supported by positive immunohistochemistry (IHC) results for cytokeratin and vimentin. IHC for thyroglobulin proved that the tissue of origin was the thyroid gland. This is the fifth canine case of thyroid carcinosarcoma to be documented, but the first one to be confirmed by specific cell markers. It is an extremely rare neoplasm that also occurs in people.
Sequential Pathology after Experimental Infection with Marine Viral Hemorrhagic Septicemia Virus Isolates of Low and High Virulence in Turbot (Scophthalmus maximus L.)
Authors: Brudeseth B. E. , Raynard R. S. , King J. A. , Evensen Ø.
Published: January 2005

Three marine viral hemorrhagic septicemia virus isolates were used to bath challenge turbot with the purpose of studying mortality and the pathology and antigen distribution over time. Two high-virulence isolates, 860/94, 4p168 and a low-virulence isolate 1p3 from a Baltic Sea herring were used. Organ samples were collected sequentially at 2, 4, 7, 10, 15, 20, 25, and 45 days postinfection. Specimens were processed for virology, histopathology, and immunohistochemistry. Organs during the early stages of infection (from 2 to 7 days) had virus isolation from all three groups only on day 7. Virus titer in kidney and heart sampled at day 25 was higher for the two virulent isolates compared with the low-virulence isolate. The viral distribution in situ of the two more virulent isolates from turbot (860/94) and herring (4p168) resembled viral hemorrhagic septicemia in rainbow trout with regard to the target organs. Early infection of endothelial cells in both kidney and heart was observed. Accumulated mean mortality was 41.5% for the turbot isolate 860/94, 48% for the herring isolate 4p168, and 3.5% for the herring isolate 1p3. This study revealed that the isolates from turbot (860/94) and herring (4p168) induced significantly higher mortality compared with the virus-free control and the herring isolate (1p3). The onset of mortality is markedly later in turbot compared with what is seen in rainbow trout.
Melanotroph Pituitary Adenoma in a Cat with Diabetes Mellitus
Authors: Meij B. P. , van der Vlugt-Meijer R. H. , van den Ingh T. S. G. A. M. , Flik G. , Rijnberk A.
Published: January 2005

A 13-year-old male, castrated, crossbred cat was referred for insulin-resistant diabetes mellitus. The cat had a ravenous appetite and a dull coat. Basal urinary corticoid/creatinine ratios were normal. In the low-dose dexamethasone suppression test there was no suppression of the (nonelevated) plasma cortisol concentration, whereas the (nonelevated) plasma adrenocorticotropic hormone (ACTH) concentration declined to low values. Basal plasma α-melanocyte-stimulating hormone (α-MSH) concentrations were highly elevated (> 1,500 ng/liter). Computed tomography revealed a pituitary tumor originating from the pars intermedia (PI). After microsurgical transsphenoidal hypophysectomy, the clinical signs resolved and the cat no longer required insulin administration. Microscopic examination of the surgical specimen revealed a pituitary adenoma originating from the PI with infiltration into the neural lobe. The adenoma immunostained intensely positive for α-MSH and only weakly for ACTH. It is concluded that the ACTH-independent cortisol production was probably due to the (weak) glucocorticorticotropic effects of the extremely high plasma concentration of α-MSH and related peptides.
Oxytocin- and vasopressin-induced growth of human small-cell lung cancer is mediated by the mitogen-activated protein kinase pathway
Authors: Péqueux C , Keegan B P , Hagelstein M-T , Geenen V , Legros J-J , North W G
Published: January 2005

Malignant growth of small-cell lung carcinoma is promoted by various neuroendocrine autocrine/paracrine loops. Therefore, to interfere with this mitogenic process, it is crucial to elucidate the mechanisms involved. It is known that the oxytocin (OT) and vasopressin (VP) genes, normally transcriptionally restricted in their expression, are activated in small-cell lung cancer (SCLC), concomitantly with expression of their receptors (OTR, V1aR, V1bR/V3R and V2R). The aim of the present study was to characterize, in concentrations close to physiological and pharmacological conditions, intracellular signalling events triggered by OT and VP binding to their specific receptors in SCLC cells and to identify factors mediating OT- and VP-induced mitogenic effects on SCLC. Known agonists for OTR ([Thr4,Gly7]OT) and V1aR (F180), in addition to OT and VP, were able to elicit increases in cytosolic Ca2+ levels and this effect could be blocked using an OTR antagonist (OVTA) or a V1aR antagonist (SR49059) respectively. There was no activation of the cAMP pathway detected after VP, dDAVP (a V2R agonist), or OT treatment. Stimulation of SCLC cells with OT and VP led to an increase of extracellular signal-regulated kinase (ERK) 1/2 phosphorylation, maximal at 5 min, and the subsequent phosphorylation of its downstream target p90 ribosomal S6 kinase (p90RSK). Pre-incubation with OVTA and SR49059, and with inhibitors of phospholipase C (PLC), protein kinase C (PKC), mitogen-activated protein kinase/ERK kinase (MEK) 1/2 and a Ca2+ chelator significantly reduced OT- and VP-induced ERK1/2 phosphorylations. OVTA, SR49059 as well as MEK1/2 and PKC inhibitors also downregulated OT- and VP-induced p90RSK phosphorylation. In [3H]thymidine-uptake experiments, we subsequently observed that PLC, Ca2+, PKC and ERK1/2 are absolutely required for the OT- and VP-stimulated SCLC cellular growth process. In conclusion, the results presented here indicate that OT- and VP-induced mitogenic effects on SCLC are respectively mediated by OTR and V1aR signalling and that this mitogenic signalling passes through the phosphorylation of ERK1/2 and p90RSK in a PLC-, Ca2+-, PKC- and MEK1/2-dependent pathway.
The influence of the progression of secondary hyperparathyroidism on the set point of the parathyroid hormone-calcium curve
Authors: Bas S , Aguilera-Tejero E , Bas A , Estepa J C , Lopez I , Madueño J A , Rodriguez M
Published: January 2005

The influence of secondary hyperparathyroidism (2 HPT) on the set point of the parathyroid hormone (PTH)-Ca2+ curve is controversial. In vitro experiments have shown an increase in the set point. However, clinical studies with hemodialysis patients have provided a variety of results (increases, decreases and no changes in the set point have been reported). The present study was designed to investigate the influence of the progression of 2 HPT on the set point of the PTH-Ca2+ curve. The PTH-Ca2+ curve and the expression of parathyroid calcium receptor (CaR mRNA) and vitamin D receptor (VDR mRNA) have been studied in normal rabbits (group I, n=9) and in nephrectomized rabbits (group II, n=18) at two stages after inducing 2 HPT: 2–3 weeks (group IIA) and 5–6 weeks (group IIB). In group I, the set point of the PTH-Ca2+ curve was 1.63±0.03 mM. A progressive hypocalcemia was detected during the evolution of 2 HPT (groups IIA and IIB). Rabbits from group IIA had a significant (P<0.001) decrease in the set point to values of 1.45±0.02 mM. However, the set point increased significantly in group IIB (P<0.001) to 1.56±0.03 mM. CaR mRNA was similarly decreased in groups IIA (39±12%) and IIB (48±7%). No changes were detected in VDR mRNA. In conclusion, a reduction in the set point of the PTH-Ca2+ curve in response to decreased extracellular Ca2+ was detected in the early phases of 2 HPT. However, with the progression of 2 HPT the set point tended to increase even though extracellular Ca2+ was markedly decreased. The increase in the set point in the course of 2 HPT seems to be a complex process that cannot be fully explained by changes in parathyroid CaR mRNA or VDR mRNA.
Manganese superoxide dismutase activity in the rat adrenal
Authors: Raza F S , Okamoto M , Takemori H , Vinson G P
Published: January 2005

In the light of studies suggesting that transcription of the gene coding for manganese superoxide dismutase (MnSOD) is induced by ACTH in the rat adrenal gland, northern blot analysis was used to determine its mRNA distribution. It was found that mRNA coding for MnSOD is primarily present in the inner zones of the rat adrenal cortex, and not the glomerulosa. To investigate the functional relationships between MnSOD activity and expression and adrenocortical function, adrenals and blood were taken from animals pretreated with corticotrophin or betamethasone (Betnesol), or subjected to a low-sodium diet. MnSOD activity in inner zone mitochondrial fractions was enhanced by corticotrophin and by a low-sodium diet, but suppressed by betamethasone. Apparent cytosolic MnSOD activity, total cytosolic MnSOD and CuZnMn-SOD, and glomerulosa mitochondrial MnSOD all were unaffected. Steroid assays showed a clear correlation between circulating corticosterone and inner zone mitochondrial MnSOD, but none between aldosterone and glomerulosa MnSOD.

Immunoblot analysis of MnSOD showed two apparent isoforms, at approximately 25 kDa and 75 kDa. There was a partial relationship between expression of the 75 kDa isoform and MnSOD activity, in that it was induced by corticotrophin. However, there was also a slight induction with betamethasone, and a low-sodium diet had no effect. The 25 kDa MnSOD isoform was unaffected by the treatments. The results suggest that MnSOD may have a specific role in the steroidogenic function of the fasciculata/reticularis of the rat adrenal, but not in that of the glomerulosa.
Ghrelin regulates proliferation and differentiation of osteoblastic cells
Authors: Maccarinelli Giuseppina , Sibilia Valeria , Torsello Antonio , Raimondo Francesca , Pitto Marina , Giustina Andrea , Netti Carmela , Cocchi Daniela
Published: January 2005

It has previously been reported that growth hormone secretagogues (GHS) may have a role in the regulation of bone metabolism in animals and humans. In this study we evaluated the effect of ghrelin, the endogenous ligand of GHS receptors, on the proliferation rate and on osteoblast activity in primary cultures of rat calvaria osteoblasts. In the same experiments, we compared the effects of ghrelin with those of hexarelin (HEXA) and EP-40737, two synthetic GHS with different characteristics. Both ghrelin and HEXA (10−11−10−8 M) significantly stimulated osteoblast proliferation at low concentrations (10−10 M). Surprisingly, EP-40737 demonstrated an antiproliferative effect at 10−9−10−8 M, whereas lower concentrations had no effect on cell proliferation. Ghrelin and HEXA significantly increased alkaline phosphatase (ALP) and osteocalcin (OC) production. At variance with these peptides, EP-40737 did not significantly stimulate ALP and OC. The mRNA for GHS-R1a receptors and the corresponding protein were detected in calvarial osteoblasts by RT-PCR and Western blot respectively, indicating that ghrelin and GHS may bind and activate this specific receptor. We conclude that endogenous ghrelin and synthetic GHS modulate proliferation and differentiation of rat osteoblasts, probably by acting on their specific receptor.
Evidence that androgens and oestrogens, as well as follicle-stimulating hormone, can alter Sertoli cell number in the neonatal rat
Authors: Atanassova Nina N , Walker Marion , McKinnell Chris , Fisher Jane S , Sharpe Richard M
Published: January 2005

Neonatal treatment of male rats with diethylstilboestrol (DES) or a gonadotrophin-releasing hormone antagonist (GnRHa) reduces final Sertoli cell number, an effect presumed to occur via suppression of follicle-stimulating hormone (FSH). As both treatments also suppress androgen action, we investigated whether androgens and oestrogens might affect Sertoli cell nuclear volume/number in the rat using single or combined treatments that differentially affected FSH, testosterone and oestrogen (DES) levels. Neonatal treatment with flutamide (50 mg/ kg) significantly reduced Sertoli cell nuclear volume/ number per testis and blood inhibin-B levels at day 18, despite elevating FSH levels; this treatment also exacerbated the reduction in Sertoli cell nuclear volume per testis induced by treatment with 0.1 μg DES without affecting FSH levels. Treatment with 0.1 μg DES on its own also reduced Sertoli cell nuclear volume per testis without affecting FSH/testosterone levels, but co-administration of 0.1 μg DES+GnRHa, which suppressed FSH and testosterone levels, resulted in a markedly greater effect. Treatment with GnRHa alone or 10 μg DES alone grossly suppressed FSH and testosterone levels and reduced Sertoli cell nuclear volume/number per testis by approximately 60%, but co-administration of the two treatments had no greater effect than either alone. Co-administration of testosterone esters with 10 μg DES partially prevented the 10 μg DES-induced reduction in Sertoli cell nuclear volume per testis, and normalized FSH levels. In all treatment groups, plasma levels of inhibin-B paralleled changes in Sertoli cell nuclear volume/number per testis, but treatments that suppressed FSH levels (GnRHa, 10 μg DES) caused a proportionately greater reduction (approximately 90%) in inhibin-B levels than in Sertoli cell nuclear volume/number (50–60%). Germ cell volume per unit Sertoli cell was reduced in animals treated with 10 μg DES alone or in those treated with 0.1 μg DES plus either flutmaide or GnRHa, but otherwise remained relatively constant between treatment groups. It is concluded that, in the neonatal rat, (1) endogenous androgens, as well as FSH, play a physiological role in increasing Sertoli cell number, (2) exogenous oestrogen exposure can decrease Sertoli cell number without altering FSH levels, (3) these effects probably share a common pathway and (4) blood inhibin-B provides a robust indicator of change in Sertoli cell number.
Stereotactic Body and Conventional Radiotherapy for Painful Bone Metastases
Authors: Bindels Bas J. J. , Mercier Carole , Gal Roxanne , Verlaan Jorrit-Jan , Verhoeff Joost J. C. , Dirix Piet , Ost Piet , Kasperts Nicolien , van der Linden Yvette M. , Verkooijen Helena M. , van der Velden Joanne M.
Published: February 2024

Importance

Conventional external beam radiotherapy (cEBRT) and stereotactic body radiotherapy (SBRT) are commonly used treatment options for relieving metastatic bone pain. The effectiveness of SBRT compared with cEBRT in pain relief has been a subject of debate, and conflicting results have been reported.

Objective

To compare the effectiveness associated with SBRT vs cEBRT for relieving metastatic bone pain.

Data Sources

A structured search was performed in the PubMed, Embase, and Cochrane databases on June 5, 2023. Additionally, results were added from a new randomized clinical trial (RCT) and additional unpublished data from an already published RCT.

Study Selection

Comparative studies reporting pain response after SBRT vs cEBRT in patients with painful bone metastases.

Data Extraction and Synthesis

Two independent reviewers extracted data from eligible studies. Data were extracted for the intention-to-treat (ITT) and per-protocol (PP) populations. The study is reported following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline.

Main Outcomes and Measures

Overall and complete pain response at 1, 3, and 6 months after radiotherapy, according to the study’s definition. Relative risk ratios (RRs) with 95% CIs were calculated for each study. A random-effects model using a restricted maximum likelihood estimator was applied for meta-analysis.

Results

There were 18 studies with 1685 patients included in the systematic review and 8 RCTs with 1090 patients were included in the meta-analysis. In 7 RCTs, overall pain response was defined according to the International Consensus on Palliative Radiotherapy Endpoints in clinical trials (ICPRE). The complete pain response was reported in 6 RCTs, all defined according to the ICPRE. The ITT meta-analyses showed that the overall pain response rates did not differ between cEBRT and SBRT at 1 (RR, 1.14; 95% CI, 0.99-1.30), 3 (RR, 1.19; 95% CI, 0.96-1.47), or 6 (RR, 1.22; 95% CI, 0.96-1.54) months. However, SBRT was associated with a higher complete pain response at 1 (RR, 1.43; 95% CI, 1.02-2.01), 3 (RR, 1.80; 95% CI, 1.16-2.78), and 6 (RR, 2.47; 95% CI, 1.24-4.91) months after radiotherapy. The PP meta-analyses showed comparable results.

Conclusions and Relevance

In this systematic review and meta-analysis, patients with painful bone metastases experienced similar overall pain response after SBRT compared with cEBRT. More patients had complete pain alleviation after SBRT, suggesting that selected subgroups will benefit from SBRT.
Characteristics and functions of predictive and directive memories and forecasts
Authors: Ay Demet , Gülgöz Sami
Published: February 2024

Earlier research focused on three functions of recollecting the past self, social, and directive functions, but few studies examined the characteristics of events serving these functions. Moreover, research has neglected the function of prediction, which refers to predicting the future by recollecting the past. The current study distinguished the predictive function from the directive function and aimed to characterize memories and future events serving different functions by employing function prompts as cues. In addition, the frequency of using function‐cued memories for the other functions was measured. Results showed that predictive and directive function ratings of the predictive function cued events were significantly different. However, directive events served the predictive function as frequently as the directive function, indicating that the predictive function is a prerequisite for future planning conceptualized under the directive function. The results are indicative of a distinct predictive function and considerable overlap between functions of memories.
Large‐Scale Artificial Production of Coleoptera Cuticle Iridescence and Its Use in Conformal Biodegradable Coatings
Authors: Kompa Akshayakumar , Finet Cédric , Saranathan Vinodkumar , Fernandez Javier G
Published: February 2024

In this study, bioinspired chitinous manufacturing is leveraged to artificially reproduce iridescent gratings found in the cuticles of beetles living in concealed environments. Combining this with a melanin‐like background achieves a vibrant iridescence, similar to that produced by the multilayer reflectors in leaf beetles. In this process, the controlled production of optical structures is allowed using chitinous polymers, the same components that produce color in arthropod cuticles. This not only aids in understanding the functionality and evolutionary advantages of these structures without being limited to the existing solutions in animals—which entangle the solutions for several problems with the rubble of past functionalities—but also enables the creation of color with the second most abundant organic material on Earth, only surpassed in its ubiquity by cellulose. However, unlike cellulose‐based materials, the chitinous optical structures are produced by avoiding the use of strong organic solvents, representing a simplified approach to producing vibrant, iridescent, fully biodegradable, and ecologically integrated colors. Herein, the production of hundreds of square centimeters of iridescent chitinous surfaces, a scale suitable for imparting biodegradable color to large 3D objects, is demonstrated.
Effect of Tool Geometry on the Microstructure of Friction Stir Welding of Copper and 316L Stainless Steel
Authors: Huser Gautier , Martinez Celis Mayerling , Picot Florent , Minárik Peter , Veselý Jozef , Helbert Anne‐Laure , Hug Eric
Published: February 2024

The microstructure evolution during dissimilar friction stir welding of copper with stainless steel 316L is studied. The welding is performed in transparence configuration using tools of two different geometries. The joints are characterized by optical microscopy, scanning and transmission electron microscopy, electron backscattered diffraction, and microhardness. The microstructure and crystallographic texture of base metals are significantly affected. The joint produced using a shoulder of 8 mm in diameter is characterized by a copper nugget with refined grains. The texture of copper is dominated by component of the shear texture. The steel beneath the tool shows a grain refinement with grains of sub‐micron size and a texture which is close to the ideal simple shear texture. For the joint produced by the 16 mm diameter tool shoulder, the nugget consists of large grains of copper, while the steel beneath the tool shows small recrystallized grains of micrometer size. The texture in the steel is dominated by the component of the shear texture. The Cu/316L interface in both types of joint is of very good quality. In a detailed study of the interface, it is revealed that the welding of metals is achieved by mutual intense mechanical interlocking without formation of any intermetallic compounds.
Highly Stable O‐Tolylbiguanide‐CsPbI3 Quantum Dots and Light‐Emitting Diodes by Synergistic Supramolecular Passivation
Authors: Li Hanming , Hua Yulu , Wang Xiaoyu , Ge Chengda , Wang Zisheng , Song Yilong , Li Xiaohui , Wang Anran , Yang Yang , Zhou Kun , Dong Wei , Zheng Weitao , Zhang Lijun , Zhang Xiaoyu , Dong Qingfeng
Published: February 2024

Developing effective strategy to passivate surface defects in quantum dots (QDs) is critical to achieving high‐efficiency and long‐life perovskite light‐emitting diodes (LEDs). Here, the supramolecular interaction underpinning of organic‐inorganic components is exploited and a facile method is proposed to generate multiple‐hydrogen‐bonded supramolecular‐perovskite crystal structures on QD surfaces by introducing O‐Tolylbiguanide (O‐Tg) during QD synthesis, enabling bright, conductive, and water‐resistant CsPbI3 QDs. Compared with commonly used oleic acid and oleylamine ligands, the biguanide functional group in O‐Tg not only forms multiple hydrogen bond interactions with lead halide octahedra passivating both bridging‐ and terminal‐halogen ion defects, but also compatibly occupies the A‐site position stabilizing the crystal structure simultaneously. With fewer nonradiative defects and introduced hydrophobic benzene rings preventing eroding of polar molecules, CsPbI3 QDs exhibit remarkable photoluminescence quantum yields of 96%, and their film can be submerged in water for 30 h without degrading. The corresponding LEDs display a high external quantum efficiency (21.2%) and offer superior operational stability with a lifetime (T90) of 25 h at a constant current density as high as 50 mA cm−2.
Oxidation‐Responsive Supramolecular Hydrogel Based on a Simple Fmoc‐Cysteine Derivative Capable of Showing Autonomous Gel–Sol–Gel Transitions
Authors: Shintani Yuki , Katagiri Hiroshi , Ikeda Masato
Published: February 2024

Aqueous soft matter, including supramolecular hydrogels capable of exhibiting stimuli–responsive macroscopic phase transitions, has attracted increasing attention for the exploration of functional soft materials. However, the investigation of supramolecular hydrogels that undergo autonomous and multiple macroscopic phase transitions (e.g., gel–sol–gel, sol–gel–sol) in response to the surrounding environment without repeated additions of stimuli has remained largely unexplored. In this study, the oxidation‐responsive autonomous gel–sol–gel transitions of supramolecular hydrogels fabricated via the self‐assembly of a simple fluorenylmethyloxycarbonyl (Fmoc)‐protected, benzylated cysteine (Fmoc‐CBzl) is presented. During the evaluation of the oxidation process of Fmoc‐CBzl, it is revealed that the oxidized products, two diastereomeric sulfoxides (Fmoc‐CBzl‐(R)‐O and Fmoc‐CBzl‐(S)‐O), exhibit significantly different self‐assembly propensities under aqueous conditions. It may be noteworthy that the chirality of sulfoxide is largely overlooked and not effectively used to modulate supramolecular, self‐assembled nanostructures. The difference in the self‐assembly propensities and kinetics of self‐assembly/disassembly as well as co‐assembly will contribute to oxidation‐responsive autonomous gel–sol–gel transitions.
Advances in Green Triboelectric Nanogenerators
Authors: Du Taili , Chen Zhixiang , Dong Fangyang , Cai Hu , Zou Yongjiu , Zhang Yuewen , Sun Peiting , Xu Minyi
Published: February 2024

Triboelectric nanogenerator (TENG), an emerging energy conversion technology, offers innovative pathways for energy harvesting and self‐powered sensing. To achieve superior performance, researchers commonly employ substantial quantities of original or treated polymers, resulting in high energy and precise sensing. Nevertheless, the sustainable development of TENGs faces significant challenges related to environmental compatibility, pollution hazards, and high production and disposal costs. To address this issue, numerous green materials for diverse TENGs are introduced and advanced. These materials may encompass natural resources, household waste, and recyclable materials, among others. Consequently, a review of the progress in TENGs based on green materials, which can be called green TENGs, becomes imperative to advance its sustainable development. To this end, this work comprehensively elucidates the development of green TENGs from the perspective of materials processing and treatment degree for the first time. Various green TENGs, including food waste, discarded daily‐use items, plant organs, biodegradable industrial products, and natural cellulose, are meticulously categorized. This review not only systematically synthesizes the latest research advancements in green TENGs, but also offers insight into their processing methodologies, working characteristics, and potential application scenarios. Finally, it envisions the challenges, proposed solutions, and future research directions for the development of green TENGs.
Na2.5VTi0.5Al0.5(PO4)3 as Long Lifespan Cathode for Fast Charging Sodium‐Ion Batteries
Authors: Li Zechen , Sun Chen , Li Meng , Wang Xiaoyang , Li Yang , Yuan Xuanyi , Jin Haibo , Zhao Yongjie
Published: February 2024

Vanadium based NASICON‐type cathodes are faced with the exorbitant cost and underdeveloped multi‐electrons reaction of V species. In this work, a strategy of increased covalency of the NASICON framework combined with the reversible activation of V4+/V5+ couple is proposed to improve the electrochemical performance together with energy density of V‐based cathodes. Making full use of V2+/V3+/V4+/V5+ and Ti3+/Ti4+ redox couples, Na2.5VTi0.5Al0.5(PO4)3 exhibits admirable electrochemical performance, including a high specific capacity of 160.9 mAh g−1 at 0.1 C and favorable cycling stability (a capacity retention of 88.3% at 20 C after 1000 cycles). Moreover, this cathode displays outstanding low temperature performance at 0 °C with a capacity retention of 89% after 1200 cycles at 5 C. In situ XRD and EIS analysis are conducted to reveal the Na+ storage mechanism. The cathode reveals a lattice volume variation of 2.16% upon cycling, which is responsible for the high structural stability during the extraction and intercalation process of Na+. Applying Na2.5VTi0.5Al0.5(PO4)3 as both cathode and anode electrode, the symmetric cell is assembled and displays exceptional capacity of 59.8 mAh g−1 at 20 C. The research provides an effective routine to stimulate the electrochemical potential of V‐based electrode materials.
Covalent Adaptable Networks with Dual Dynamic Covalent Bonds for Self‐Repairing Infrared Transmitting Materials
Authors: Cui Chenhui , Wang Fang , Chen Xingxing , Xu Ting , Li Zhen , Chen Kexiang , Guo Yinzhou , Cheng Yilong , Ge Zhishen , Zhang Yanfeng
Published: February 2024

Infrared transmitting materials (IRTMs) are prone to mechanical and corrosion damage during long‐time exposure to harsh outside environments. However, conventional IRTMs frequently lack self‐repairability that limit their lifespan. To address the limitation, thioctic acid‐based epoxy resins (TAEs) are developed from natural thioctic acid and commercial epoxy monomers. The double ring‐opening polymerization (ROP) reactions of thioctic acid and epoxy groups result in dual dynamic covalent bonds with varying bond energies containing relatively weak disulfide bonds and strong ester bonds. As compared with conventional covalent adaptable networks (CANs) that present rapid creep properties when heated, TAEs maintain their geometric stability during rapid self‐repairing at a mild temperature of 80 °C by enhancing network integrity through stable ester crosslinking points. The feature renders TAEs self‐repairing capability while maintaining precise geometrical dimensions, which is suitable for infrared transmitting devices. On the other hand, TAEs exhibit high near‐infrared transmittance (>80%). Therefore, TAEs with self‐repairability and high infrared transmittance demonstrate they can be used as superior polymeric IRTM.
Ferredoxin‐Inspired Design of S‐Synergized Fe–Fe Dual‐Metal Center Catalysts for Enhanced Electrocatalytic Oxygen Reduction Reaction
Authors: Liu Ming , Wang Xuemin , Cao Shoufu , Lu Xiaoqing , Li Wei , Li Na , Bu Xian‐He
Published: February 2024

Dual‐metal center catalysts (DMCs) have shown the ability to enhance the oxygen reduction reaction (ORR) owing to their distinctive structural configurations. However, the precise modulation of electronic structure and the in‐depth understanding of synergistic mechanisms between dual metal sites of DMCs at the atomic level remain challenging. Herein, mimicking the ferredoxin, Fe‐based DMCs (Fe2N6‐S) are strategically designed and fabricated, in which additional Fe and S sites are synchronously installed near the Fe sites and serve as “dual modulators” for coarse‐ and fine‐tuning of the electronic modulation, respectively. The as‐prepared Fe2N6‐S catalyst exhibits enhanced ORR activity and outstanding Zinc‐air (Zn–air) battery performance compared to the conventional single Fe site catalysts. The theoretical and experimental results reveal that introducing the second metal Fe creates a dual adsorption site that alters the O2 adsorption configuration and effectively activates the O─O bond, while the synergistic effect of dual Fe sites results in the downward shift of the d‐band center, facilitating the release of OH*. Additionally, local electronic engineering of heteroatom S for Fe sites further facilitates the formation of the rate‐determining step OOH*, thus accelerating the reaction kinetics.
Blood–Brain Barrier‐Penetrating and Lesion‐Targeting Nanoplatforms Inspired by the Pathophysiological Features for Synergistic Ischemic Stroke Therapy
Authors: Tang Lu , Yin Yue , Liu Hening , Zhu Mengliang , Cao Yuqi , Feng Jingwen , Fu Cong , Li Zixuan , Shu Weijie , Gao Jifan , Liang Xing‐Jie , Wang Wei
Published: February 2024

Ischemic stroke is a dreadful vascular disorder that poses enormous threats to the public health. Due to its complicated pathophysiological features, current treatment options after ischemic stroke attack remains unsatisfactory. Insufficient drug delivery to ischemic lesions impeded by the blood–brain barrier (BBB) largely limits the therapeutic efficacy of most anti‐stroke agents. Herein, inspired by the rapid BBB penetrability of 4T1 tumor cells upon their brain metastasis and natural roles of platelet in targeting injured vasculatures, a bio‐derived nanojacket is developed by fusing 4T1 tumor cell membrane with platelet membrane, which further clothes on the surface of paeonol and polymetformin‐loaded liposome to obtain biomimetic nanoplatforms (PP@PCL) for ischemic stroke treatment. The designed PP@PCL could remarkably alleviate ischemia‐reperfusion injury by efficiently targeting ischemic lesion, preventing neuroinflammation, scavenging excess reactive oxygen species (ROS), reprogramming microglia phenotypes, and promoting angiogenesis due to the synergistic therapeutic mechanisms that anchor the pathophysiological characteristics of ischemic stroke. As a result, PP@PCL exerts desirable therapeutic efficacy in injured PC12 neuronal cells and rat model of ischemic stroke, which significantly attenuates neuronal apoptosis, reduces infarct volume, and recovers neurological functions, bringing new insights into exploiting promising treatment strategies for cerebral ischemic stroke management.
Strategies to Modulate the Copper Oxidation State Toward Selective C2+ Production in the Electrochemical CO2 Reduction Reaction
Authors: Jun Minki , Kundu Joyjit , Kim Duck Hyun , Kim Minah , Kim Dongyong , Lee Kwangyeol , Choi Sang‐Il
Published: February 2024

The electrochemical reduction of CO2 to form value‐added chemicals receives considerable attention in recent years. Copper (Cu) is recognized as the only element capable of electro‐reducing CO2 into hydrocarbons with two or more carbon atoms (C2+), but the low product selectivity of the Cu‐based catalyst remains a major technological challenge to overcome. Therefore, identification of the structural features of Cu‐based catalysts is of great importance for the highly selective production of C2+ products (ethylene, ethanol, n‐propanol, etc.), and the oxidation state of Cu species in the catalysts is found critical to the catalyst performance. This review introduces recent efforts to fine‐tune the oxidation state of Cu to increase carbon capture and produce specific C2+ compounds, with the intention of greatly expediting the advance in the catalyst designs. It also points to the remaining challenges and fruitful research directions for the development of Cu‐based catalysts that can shape the practical CO2 reduction technology.
High‐Safety Electrolytes with an Anion‐Rich Solvation Structure Tuned by Difluorinated Cations for High‐Voltage Lithium Metal Batteries
Authors: Ding Fangwei , Li Yixing , Zhang Guoxu , Wang Hongyu , Liu Bo , Liu Chang , Jiang Linhai , Sui Xulei , Wang Zhenbo
Published: February 2024

As next‐generation energy storage devices, lithium metal batteries (LMBs) must offer high safety, high‐voltage resistance, and a long life span. Electrolyte engineering is a facile strategy to tailor the interfacial chemistry of LMBs. In particular, the solvation structure and derived solid electrolyte interphase (SEI) are crucial for a satisfactory battery performance. Herein, a novel middle‐concentrated ionic liquid electrolyte (MCILE) with an anion‐rich solvation structure tuned by difluorinated cations is demonstrated to achieve ultrahigh safety, high‐voltage stability, and excellent ternary‐cathode compatibility. Novel gem‐difluorinated cations first synthesized for prestoring fluorine on positively charged species, not only preferentially adsorb in the inner‐Helmholtz layers, but also participate in regulating the Li+ solvation structure, resulting in a robust interphase. Moreover, these weak interactions in the Li+ solvation structure including anion–solvent and ionic liquid (IL) cation–solvent pairs are first revealed, which are beneficial for promoting an anion‐dominated solvation structure and the desolvation process. Benefiting from the unique anion‐rich solvation structure, a stable hetero‐SEI structure is obtained. The designed MCILE exhibits compatibility with Li metal anode and the high‐voltage ternary cathode at high temperatures (60 °C). This work provides a new approach for regulating the solvation structure and electrode interphase chemistry of LMBs via difluorinated IL cations.
Microfluidic Metasurface with Constant Absorption Efficiency Throughout the Ku Band
Authors: Qin Jin , Gao Yusong , Zhang Wu , Xiong Sha , Zhu Weiming
Published: February 2024

Metasurfaces with designable electromagnetic parameters are ideal candidates for broadband and tunable microwave absorbers. Water‐based metasurface microwave absorbers have been demonstrated to exhibit ultra‐broadband and near‐unity absorption. However, a broadband microwave absorber with constant and designable efficiencies remains a challenge due to stringent impedance‐matching conditions over a large frequency region. In this work, a design paradigm of microfluidic metasurface absorbers is proposed to regulate absorption efficiency over a wide frequency range. As an example, microfluidic metasurface absorbers are demonstrated with constant absorption efficiency over the Ku band, which is designable from 61.8% to 99.9%. The broadband metasurface absorbers have the advantages of easy fabrication, low cost, and optical transparency, making them highly promising for applications in fields like electromagnetic shielding, active camouflage, electromagnetic pollution control, and wireless communications.
Reconfigurable Tri‐Mode Metasurface for Broadband Low Observation, Wide‐Range Tracing, and Backscatter Communication
Authors: Ning Jing , Zheng Yilin , Wang Shaojie , Jiang Tian , Zhao Junming , Chen Ke , Feng Yijun
Published: February 2024

In the current prevalent complex electromagnetic (EM) environment, intelligent methods for versatile and integrated control of EM waves using compact devices are both essential and challenging. These varied wave control objectives can at times conflict with one another, such as the need for broad absorption to remain inconspicuous, while also requiring enhanced backward scattering for highly reliable tracing and secure communication. To address these sophisticated challenges, a microwave‐frequency reconfigurable tri‐mode metasurface (RTMM) is introduced. The proposed innovation enables three distinct operational modes: broadband low observation, enhanced EM wave tracing, and backscatter communication over a wide‐angle range by simple control of the PIN diodes embedded in each meta‐atom. The proof‐of‐concept demonstration of the fabricated prototype verified the switchable tri‐mode performance of the RTMM. This proposed RTMM can be adapted to various applications, including EM shielding, target detection, and secure communication in complex and threatening EM environments, paving the way for environmentally‐adaptive EM wave manipulation.
Inflammatory Fibroblast‐Like Synoviocyte‐Derived Exosomes Aggravate Osteoarthritis via Enhancing Macrophage Glycolysis
Authors: Liu Bin , Xian Yansi , Chen Xiang , Shi Yong , Dong Jian , Yang Lin , An Xueying , Shen Tao , Wu Wenshu , Ma Yuze , He Yi , Gong Wang , Peng Rui , Lin Jiaquan , Liu Na , Guo Baosheng , Jiang Qing
Published: February 2024

The severity of osteoarthritis (OA) and cartilage degeneration is highly associated with synovial inflammation. Although recent investigations have revealed a dysregulated crosstalk between fibroblast‐like synoviocytes (FLSs) and macrophages in the pathogenesis of synovitis, limited knowledge is available regarding the involvement of exosomes. Here, increased exosome secretion is observed in FLSs from OA patients. Notably, internalization of inflammatory FLS‐derived exosomes (inf‐exo) can enhance the M1 polarization of macrophages, which further induces an OA‐like phenotype in co‐cultured chondrocytes. Intra‐articular injection of inf‐exo induces synovitis and exacerbates OA progression in murine models. In addition, it is demonstrated that inf‐exo stimulation triggers the activation of glycolysis. Inhibition of glycolysis using 2‐DG successfully attenuates excessive M1 polarization triggered by inf‐exo. Mechanistically, HIF1A is identified as the determinant transcription factor, inhibition of which, both pharmacologically or genetically, relieves macrophage inflammation triggered by inf‐exo‐induced hyperglycolysis. Furthermore, in vivo administration of an HIF1A inhibitor alleviates experimental OA. The results provide novel insights into the involvement of FLS‐derived exosomes in OA pathogenesis, suggesting that inf‐exo‐induced macrophage dysfunction represents an attractive target for OA therapy.
Synergistic Performance Boosts of Dopamine‐Derived Carbon Shell Over Bi‐metallic Sulfide: A Promising Advancement for High‐Performance Lithium‐Ion Battery Anodes
Authors: Bhattarai Roshan Mangal , Le Nghia , Chhetri Kisan , Acharya Debendra , Pandiyarajan Sudhakaran Moopri Singer , Saud Shirjana , Kim Sang Jae , Mok Young Sun
Published: February 2024

A CoMoS composite is synthesized to combine the benefits of cobalt and molybdenum sulfides as an anodic material for advanced lithium‐ion batteries (LIBs). The synthesis is accomplished using a simple two‐step hydrothermal method and the resulting CoMoS nanocomposites are subsequently encapsulated in a carbonized polydopamine shell. The synthesis procedure exploited the self‐polymerization ability of dopamine to create nitrogen‐doped carbon‐coated cobalt molybdenum sulfide, denoted as CoMoS@NC. Notably, the de‐lithiation capacity of CoMoS and CoMoS@NC is 420 and 709 mAh g⁻1, respectively, even after 100 lithiation/de‐lithiation cycles at a current density of 200 mA g⁻1. Furthermore, excellent capacity retention ability is observed for CoMoS@NC as it withstood 600 consecutive lithiation/de‐lithiation cycles with 94% capacity retention. Moreover, a LIB full‐cell assembly incorporating the CoMoS@NC anode and an NMC‐532 cathode is subjected to comprehensive electrochemical and practical tests to evaluate the performance of the anode. In addition, the density functional theory showcases the increased lithium adsorption for CoMoS@NC, supporting the experimental findings. Hence, the use of dopamine as a nitrogen‐doped carbon shell enhanced the performance of the CoMoS nanocomposites in experimental and theoretical tests, positioning the material as a strong candidate for LIB anode.