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PURPOSE: Triple-negative breast cancer (TNBC) has a poor prognosis due to the absence of effective therapeutic targets. Vascular endothelial growth factor (VEGF) family are expressed in 30-60% of TNBC, therefore providing potential therapeutic targets for TNBC. Aflibercept (Abe), a humanized recombinant fusion protein specifically bound to VEGF-A, B and placental growth factor (PIGF), has proven to be effective in the treatment in some cancers. Therefore, 89Zr/177Lu-labeled Abe was investigated for its theranostic role in TNBC. METHODS: Abe was radiolabeled with 89Zr and 177Lu via the conjugation of chelators. Flow cytometry and cell immunofluorescent staining were performed to evaluate the binding affinity of Abe. Sequential PET imaging and fluorescent imaging were conducted in TNBC tumor bearing mice following the injection of 89Zr-labeled Abe and Cy5.5-labeled Abe. Treatment study was performed after the administration of 177Lu-labeled Abe. Tumor volume and survival were monitored and SPECT imaging and biodistribution studies were conducted. Safety evaluation was performed including body weight, blood cell measurement, and hematoxylin-eosin (H&E) staining of major organs. Expression of VEGF and CD31 was tested by immunohistochemical staining. Dosimetry was estimated using the OLINDA software. RESULTS: FITC-labeled Abe showed a strong binding affinity to VEGF in TNBC 4T1 cells and HUVECs by flow cytometry and cell immunofluorescence. Tumor uptake of 89Zr-labeled Abe peaked at 120 h (SUVmax = 3.2 ± 0.64) and persisted before 168 h (SUVmax = 2.54 ± 0.42). The fluorescence intensity of the Cy5.5-labeled Abe group surpassed that of the Cy5.5-labeled IgG group, implying that Cy5.5-labeled Abe is a viable candidate monitoring in vivo tumor targeting and localization. 177Lu-labeled Abe (11.1 MBq) served well as the therapeutic component to suppress tumor growth with standardized tumor volume at 16 days, significantly smaller than PBS group (about 815.66 ± 3.58% vs 3646.52 ± 11.10%, n = 5, P < 0.01). Moreover, SPECT images confirmed high contrast between tumors and normal organs, indicating selective tumor uptake of 177Lu-labeled Abe. No discernible abnormalities in blood cells, and no evident histopathological abnormality observed in liver, spleen, and kidney. Immunohistochemical staining showed that 177Lu-labeled Abe effectively inhibited the expression of VEGF and CD31 of tumor, suggesting that angiogenesis may be suppressed by 177Lu-labeled Abe. The whole-body effective dose for an adult human was estimated to be 0.16 mSv/MBq. CONCLUSION: 89Zr/177Lu-labeled Abe could be a TNBC-specific marker with diagnostic value and provide insights into targeted therapy in the treatment of TNBC. Further clinical evaluation and translation may be of high significance for TNBC.
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Carbocianinas , Receptores de Factores de Crecimiento Endotelial Vascular , Neoplasias de la Mama Triple Negativas , Factor A de Crecimiento Endotelial Vascular , Femenino , Humanos , Animales , Ratones , Factor A de Crecimiento Endotelial Vascular/metabolismo , Neoplasias de la Mama Triple Negativas/diagnóstico por imagen , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Medicina de Precisión , Distribución Tisular , Línea Celular Tumoral , Factor de Crecimiento Placentario/metabolismo , Proteínas Recombinantes de Fusión/uso terapéutico , Proteínas Recombinantes de Fusión/metabolismoRESUMEN
Vascular endothelial growth factor (VEGF) targeted therapy serves as an important therapeutic approach for renal cancer, but its clinical effectiveness is unsatisfactory. Moreover, there is a lack of reliable biomarkers for preoperative assessment of tumor VEGF expression. This study aimed to explore the potential for further applications of 177Lu/89Zr-labeled aflibercept (Abe), a VEGF-binding agent, in imaging visualization of VEGF expression and therapy for renal cancer. To determine specificity uptake in renal cancer, BALB/c mice with VEGF-expressing Renca tumor were intravenously injected with [89Zr]Zr-Abe, [177Lu]Lu-Abe, or Cy5.5-Abe and the blocking group was designed as a control group. PET, SPECT, and fluorescence images were acquired, and the biodistribution of [89Zr]Zr-Abe and [177Lu]Lu-Abe was performed. Additionally, the [177Lu]Lu-Abe, [177Lu]Lu-Abe-block, 177Lu only, Abe only, and PBS groups were compared for evaluation of the therapeutic effect. To assess the safety, we monitored and evaluated the body weight, blood biochemistry analysis, and whole blood analysis and major organs were stained with hematoxylin and eosin after [177Lu]Lu-Abe treatment. DOTA-Abe was successfully labeled with 177Lu and Df-Abe with 89Zr in our study. The uptake in tumor of [89Zr]Zr-Abe was significantly higher than that of [89Zr]Zr-Abe-block (P < 0.05) and provided excellent tumor contrast in PET images. [177Lu]Lu-Abe demonstrated promising tumor-specific targeting capability with a high and persistent tumor uptake. The standardized tumor volume of [177Lu]Lu-Abe was significantly smaller than those of other treatment groups (P < 0.05). [177Lu]Lu-Abe also had smaller tumor volumes and reduced expression of VEGF and CD31 compared to those of the control groups. Fluorescence images demonstrate higher tumor uptake in the Cy5.5-Abe group compared to the Cy5.5-Abe-block group (P < 0.05). In conclusion, [89Zr]Zr-Abe enables noninvasive analysis of VEGF expression, serving as a valuable tool for assessing the VEGF-targeted therapy effect. Additionally, all of the findings support the enhanced therapeutic efficacy and safety of [177Lu]Lu-Abe, making it a viable option for clinical practice in renal cancer.
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Neoplasias Renales , Lutecio , Ratones Endogámicos BALB C , Radioisótopos , Receptores de Factores de Crecimiento Endotelial Vascular , Proteínas Recombinantes de Fusión , Circonio , Animales , Receptores de Factores de Crecimiento Endotelial Vascular/metabolismo , Proteínas Recombinantes de Fusión/administración & dosificación , Proteínas Recombinantes de Fusión/farmacocinética , Circonio/química , Ratones , Neoplasias Renales/tratamiento farmacológico , Neoplasias Renales/diagnóstico por imagen , Neoplasias Renales/metabolismo , Distribución Tisular , Humanos , Línea Celular Tumoral , Factor A de Crecimiento Endotelial Vascular/metabolismo , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Radiofármacos/farmacocinética , Radiofármacos/química , Nanomedicina Teranóstica/métodos , Femenino , Tomografía de Emisión de Positrones/métodos , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
BACKGROUND: Postoperative cognitive dysfunction (POCD) is a common complication after anesthesia/surgery, especially among elderly patients, and poses a significant threat to their postoperative quality of life and overall well-being. While it is widely accepted that elderly patients may experience POCD following anesthesia/surgery, the exact mechanism behind this phenomenon remains unclear. Several studies have indicated that the interaction between silent mating type information regulation 2 homologue 1 (SIRT1) and brain-derived neurotrophic factor (BDNF) is crucial in controlling cognitive function and is strongly linked to neurodegenerative disorders. Hence, this research aims to explore how SIRT1/BDNF impacts cognitive decline caused by anesthesia/surgery in aged mice. METHODS: Open field test (OFT) was used to determine whether anesthesia/surgery affected the motor ability of mice, while the postoperative cognitive function of 18 months old mice was evaluated with Novel object recognition test (NORT), Object location test (OLT) and Fear condition test (FC). The expressions of SIRT1 and other molecules were analyzed by western blot and immunofluorescence staining. The hippocampal synaptic plasticity was detected by Golgi staining and Long-term potentiation (LTP). The effects of SIRT1 and BDNF overexpression as well as chemogenetic activation of glutamatergic neurons in hippocampal CA1 region of 18 months old vesicular glutamate transporter 1 (VGLUT1) mice on POCD were further investigated. RESULTS: The research results revealed that older mice exhibited cognitive impairment following intramedullary fixation of tibial fracture. Additionally, a notable decrease in the expression of SIRT1/BDNF and neuronal excitability in hippocampal CA1 glutamatergic neurons was observed. By increasing levels of SIRT1/BDNF or enhancing glutamatergic neuron excitability in the CA1 region, it was possible to effectively mitigate synaptic plasticity impairment and ameliorate postoperative cognitive dysfunction. CONCLUSIONS: The decline in SIRT1/BDNF levels leading to changes in synaptic plasticity and neuronal excitability in older mice could be a significant factor contributing to cognitive impairment after anesthesia/surgery.
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Factor Neurotrófico Derivado del Encéfalo , Región CA1 Hipocampal , Regulación hacia Abajo , Plasticidad Neuronal , Neuronas , Complicaciones Cognitivas Postoperatorias , Sirtuina 1 , Animales , Sirtuina 1/metabolismo , Sirtuina 1/genética , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Factor Neurotrófico Derivado del Encéfalo/genética , Ratones , Neuronas/metabolismo , Complicaciones Cognitivas Postoperatorias/metabolismo , Complicaciones Cognitivas Postoperatorias/etiología , Región CA1 Hipocampal/metabolismo , Masculino , Ratones Endogámicos C57BL , Potenciación a Largo Plazo , Ácido Glutámico/metabolismo , Disfunción Cognitiva/etiología , Disfunción Cognitiva/metabolismo , Disfunción Cognitiva/fisiopatologíaRESUMEN
The daily discharge of rural sewage in China occupies 30 % of the national wastewater discharge, and developing an energy-efficient, easy to operate, and decentralized rural sewage treatment technology becomes an important task. In this work, a novel rural sewage treatment technology, Electrocoagulation enhanced Gravity-Driven Membrane Bioreactor (EC-GDMBR) was exploited for the rural sewage treatment under long-term operation (160 days). Two EC-GDMBRs with various module structures of ceramic membrane (horizontal module and side module) not only displayed the desirable effluent quality, but also sustained the stable flux (8-13 LMH). The electrocoagulation, electrooxidation, biodegradation, and separation in EC-GDMBRs were able to synergistically remove the particle matter, organic (CODCr effluent <11.6 ± 1.2 mg/L) and nutrients (NH3-N effluent <0.1 mg/L, TN effluent <8.5 mg/L, TP effluent <0.05 mg/L). Besides, the high permeability of ceramic membrane and large porosity of biofilm on its surface improved the sustainability of stable flux during the long-term operation. Moreover, by analyzing bacterial abundance, Extracellular Polymeric Substances, Adenosine Tri-Phosphate and Confocal Laser Scanning Microscopy, a large number of microorganisms grew and accumulated on the carrier, as well as formed the biofilm (23.46-659.9 µm), while Nitrobacteria (1.6-4.1 %) and Nitrate (0.01-0.06 %) exited in the carrier biofilms, promoting the nitrogen removal. Compared with EC-GDMBR with side module of ceramic membrane, EC-GDMBR with horizontal module of ceramic membrane has advantages in flux behavior, organic/nutrient removal, microbial abundance/activity, abundance of nitrogen removal functional bacteria and water permeability of biofilm, because the ceramic membrane of horizontal module can promote the uniform growth of biofilm and improve the uniformity of flow penetration distribution. In general, the findings of this work verify the reliability of EC-GDMBR for the sustainable operation of wastewater treatment and improve its application value of rural sewage treatment.
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Aguas del Alcantarillado , Eliminación de Residuos Líquidos , Aguas del Alcantarillado/química , Reproducibilidad de los Resultados , Membranas Artificiales , Reactores Biológicos , Nitrógeno/metabolismo , Bacterias/metabolismoRESUMEN
Acidithiobacillus caldus is a common bioleaching bacterium that is inevitably exposed to extreme copper stress in leachates. The ArsR/SmtB family of metalloregulatory repressors regulates homeostasis and resistance in bacteria by specifically responding to metals. Here, we characterized A. caldus Cu(I)-sensitive repressor (AcsR) and gained molecular insights into this new member of the ArsR/SmtB family. Transcriptional analysis indicated that the promoter (PIII) of acsR was highly active in Escherichia coli but inhibited upon AcsR binding to the PIII-acsR region. Size exclusion chromatography and circular dichroism spectra revealed that CuI-AcsR shared an identical assembly state with apo-AcsR, as a dimer with fewer α helices, more extended strands, and more ß turns. Mutation of the cysteine site in AcsR did not affect its assembly state. Copper(I) titrations revealed that apo-AcsR bound two Cu(I) molecules per monomer in vitro with an average dissociation constant (KD) for bicinchoninic acid competition of 2.55 × 10-9 M. Site-directed mutation of putative Cu(I)-binding ligands in AcsR showed that replacing Cys64 with Ala reduces copper binding ability from two Cu(I) molecules per monomer to one, with an average KD of 6.05 × 10-9 M. Electrophoretic mobility shift assays revealed that apo-AcsR has high affinity for the 12-2-12 imperfect inverted repeats P2245 and P2270 in the acsR gene cluster and that Cu-loaded AcsR had lower affinity for DNA fragments than apo-AcsR. We developed a hypothetical working model of AcsR to better understand Cu resistance mechanisms in A. caldus. IMPORTANCE Copper (Cu) resistance among various microorganisms is attracting interest. The chemolithoautotrophic bacterium A. caldus, which can tolerate extreme copper stress (≥10 g/L Cu ions), is typically used to bioleach chalcopyrite (CuFeS2). Understanding of Cu resistance in A. caldus is limited due to scant investigation and the absence of efficient gene manipulation tools. Here, we characterized a new member of the ArsR/SmtB family of prokaryotic metalloregulatory transcriptional proteins that repress operons linked to stress-inducing concentrations of heavy metal ions. This protein can bind two Cu(I) molecules per monomer and negatively regulate its gene cluster. Members of the ArsR/SmtB family have not been investigated in A. caldus until now. The discovery of this novel protein enriches understanding of Cu homeostasis in A. caldus.
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Acidithiobacillus , Proteínas Bacterianas , Extremófilos , Transactivadores , Acidithiobacillus/genética , Acidithiobacillus/metabolismo , Bacterias/genética , Bacterias/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Sitios de Unión , Cobre/metabolismo , Extremófilos/genética , Extremófilos/metabolismo , Iones/metabolismo , Metales/metabolismo , Unión Proteica , Transactivadores/genética , Transactivadores/metabolismoRESUMEN
We present a case of a 67-year-old male presenting with severe abdominal pain, laboratory tests revealed IgG levels of 63.5 g/L, IgG4 levels of 63.7 g/L, and negative results for ANCA (Anti-Neutrophil Cytoplasmic Antibodies), Hematuria immunofixation electrophoresis, as well as Cold globulin qualitative test. 18F-FDG PET/CT revealed multiple lesions with increased metabolism in the submaxillary saliva gland, intrahepatic bile ducts, prostate, seminal vesicle glands, and the body of the pancreas. Additionally, a circular cystic-solid lesion with metabolic heterogeneity was observed in the head of the pancreas, accompanied by visible dilatation of the pancreatic duct. The diagnostic imaging suggested IgG4-related disease (IgG4-RD), while pancreatic malignancy could not be definitively ruled out. The patient underwent fine-needle aspiration (FNA) biopsies of lung nodules and the prostate gland, all of which were consistent with the diagnosis of IgG4-RD. Additionally, FNA biopsy of a pancreatic lesion is consistent with the diagnosis of pancreatic ductal adenocarcinoma.
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Enfermedad Relacionada con Inmunoglobulina G4 , Neoplasias Pancreáticas , Masculino , Humanos , Anciano , Tomografía Computarizada por Tomografía de Emisión de Positrones , Fluorodesoxiglucosa F18 , Enfermedad Relacionada con Inmunoglobulina G4/diagnóstico por imagen , Tomografía de Emisión de Positrones/métodos , Neoplasias Pancreáticas/diagnóstico por imagenRESUMEN
PURPOSE: Abnormal CD38 expression in some hematologic malignancies, including lymphoma, has made it a biomarker for targeted therapies. Daratumumab (Dara) is the first FDA-approved CD38-specific monoclonal antibody, enabling successfully immunoPET imaging over the past years. Radiolabeled Dara however has a long blood circulation and delayed tumor uptake which can limit its applications. The focus of this study is to develop 64Cu-labeled Dara-F(ab')2 for the visualization of CD38 in lymphoma models. METHODS: F(ab')2 fragment was prepared from Dara using an IdeS enzyme and purified with Protein A beads. Western blotting, flow cytometry, and surface plasmon resonance (SPR) were performed for in vitro assay. Probes were labeled with 64Cu after the chelation of 1,4,7-triazacyclononane-1,4,7-triacetic acid (NOTA). Small animal PET imaging and quantitative analysis were performed after injection of 64Cu-labeled Dara-F(ab')2, IgG-F(ab')2, and Dara for evaluation in lymphoma models. RESULTS: Flow cytometry and SPR assay proved the specific binding ability of Dara-F(ab')2 and NOTA-Dara-F(ab')2 in vitro. Radiolabeling yield of [64Cu]Cu-NOTA-Dara-F(ab')2 was over 90% and with a specific activity of 4.0 ± 0.6 × 103 MBq/µmol (n = 5). PET imaging showed [64Cu]Cu-NOTA-Dara-F(ab')2 had a rapid and high tumor uptake as early as 2 h (6.9 ± 1.2%ID/g) and peaked (9.5 ± 0.7%ID/g) at 12 h, whereas [64Cu]Cu-NOTA-Dara reached its tumor uptake peaked at 48 h (8.3 ± 1.4%ID/g, n = 4). In comparison, IgG-F(ab')2 and HBL-1 control groups found no noticeable tumor uptake. [64Cu]Cu-NOTA-Dara-F(ab')2 had significantly lower uptake in blood pool, bone, and muscle than [64Cu]Cu-NOTA-Dara and its tumor-to-blood and tumor-to-muscle ratios were significantly higher than controls. CONCLUSIONS: [64Cu]Cu-NOTA-Dara-F(ab')2 showed a rapid and high tumor uptake in CD38-positive lymphoma models with favorable imaging contrast, showing its promise as a potential PET imaging agent for future clinical applications.
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Anticuerpos Monoclonales , Linfoma , Animales , Línea Celular Tumoral , Humanos , Fragmentos Fab de Inmunoglobulinas/metabolismo , Inmunoglobulina G , Linfoma/diagnóstico por imagen , Tomografía de Emisión de Positrones/métodosRESUMEN
Chemotherapy is an important method for the treatment of lung cancer, but multidrug resistance (MDR) greatly reduces the efficacy. The superfamily of ATP-binding cassette (ABC) transport proteins is related to MDR. As a subfamily of ABC proteins, ABCG2/BCRP (breast cancer resistance protein, BCRP) is considered a major player in the development of cancer MDR. For the stratification of chemotherapeutic choices, we constructed Cy5.5- or 89Zr-labeled ABCG2-targeted monoclonal antibody (mAb) ABCG2-PKU1 for noninvasive evaluation of ABCG2 expression in lung cancer xenograft models. ABCG2 expression was screened in H460/MX (mitoxantrone resistant), H460, and H1299 human lung cancer cell lines using Western blotting. ELISA, flow cytometry, and cell immunofluorescent staining were used to evaluate the binding ability of ABCG2-PKU1 to ABCG2 antigen. Lung cancer murine xenograft models were built for in vivo experiments. ABCG2-PKU1 was labeled with Cy5.5 (Cy5.5-ABCG2) for fluorescent imaging and radiolabeled with 89Zr (89Zr-DFO-ABCG2) for immunoPET imaging following the conjugation with p-SCN-deferoxamine (DFO). In vivo imaging was performed in lung cancer models at 2, 24, 48, 72, 96, 120, 144, and 168 h postinjection. Ex vivo biodistribution was conducted after the terminal time point of imaging. Finally, tissue immunohistochemical staining was used to evaluate the tumor expression of ABCG2. Western blotting showed that the H460/MX cells had a high ABCG2 expression level whereas H460 and H1299 had moderate and low levels. ELISA, flow cytometry, and cell immunofluorescent staining results validated the good binding affinity between ABCG2-PKU1 and ABCG2. The H460/MX and H460 cells were used to build positive lung cancer models, and H1299 cells were used to build negative models. The fluorescent imaging showed that the tumor average radiant efficiency of Cy5.5-ABCG2 reached the maximum at 72 and 120 h in H460/MX and H460 respectively (n = 3, P < 0.01). The tumor uptake of Cy5.5-ABCG2 in H1299 (n = 3) was significantly lower than H460/MX and H460 (P < 0.01). ImmunoPET imaging showed that the tumor uptake of 89Zr-DFO-ABCG2 in H460/MX was significantly higher than H460, with a maximum of 4.15 ± 0.41 %ID/g and 2.81 ± 0.24 %ID/g at 168 and 144 h, respectively (n = 5, P < 0.01). The H1299 tumors showed significantly lower uptake than H460/MX and H460 (n = 5, P < 0.01). The radioactive uptake of 89Zr-DFO-ABCG2 among three groups in the heart, liver, and kidney gradually decreased over time. Ex vivo biodistribution verified the differential tumor uptake among the three groups (P < 0.01). Immunohistochemical staining revealed that the H460/MX tumor had the highest expression of ABCG2, whereas H460 and H1299 had the moderate and lowest expression, respectively. Therefore, in this study, fluorescent and immunoPET imaging of lung cancer MDR models using Cy5.5-ABCG2 and 89Zr-DFO-ABCG2 noninvasively evaluated the differential expression of ABCG2, which are expected to be used for the diagnosis and the selection for clinical treatment options for lung cancer MDR patients in future applications.
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Neoplasias Pulmonares , Mitoxantrona , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/metabolismo , Adenosina Trifosfato/metabolismo , Animales , Anticuerpos Monoclonales/metabolismo , Carbocianinas , Línea Celular Tumoral , Deferoxamina , Modelos Animales de Enfermedad , Resistencia a Múltiples Medicamentos , Resistencia a Antineoplásicos , Xenoinjertos , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Ratones , Proteínas de Neoplasias/metabolismo , Distribución TisularRESUMEN
To understand the acid-resistant mechanism of bioleaching microorganism Acidithiobacillus caldus CCTCC M 2018054, its physiology and metabolic changes at the transcriptional level under extreme acid stress were systemically studied. Scanning electron microscopy (SEM), Fourier transform infrared reflection (FTIR) and X-ray diffraction (XRD) showed that with an increase in acidity, the absorption peak of sulfur oxidation-related functional groups such as S-O decreased significantly, and a dense sulfur passivation film appeared on the surface of the ore. Confocal laser scanning microscopy (CLSM) revealed that coverage scale of extracellular polymeric substance (EPS) and biofilm fluctuated accordingly along with the increasing acid stress (pH-stat 1.5, 1.2 0.9 and 0.6) during the bioleaching process. In response to acid stress, the increased levels of intracellular glutamic acid, alanine, cysteine, and proline contributed to the maintenance of intracellular pH homeostasis via decarboxylation and alkaline neutralization. Higher unsaturated fatty acid content was closely related to membrane fluidity. Up to 490 and 447 differentially expressed genes (DEGs) were identified at pH 1.5 vs pH 1.2 and pH 1.2 vs pH 0.9, respectively, and 177 common DEGs were associated with two-component system (TCS) regulation, transporter regulation, energy metabolism, and stress response. The upregulation of kdpB helped cells defend against proton invasion, whereas the downregulation of cysB and cbl implied stronger oxidation of sulfur compounds. The transcriptional level of sqr, sor, and soxA was significantly increased and consolidated the energy supply needed for resisting acid stress. Furthermore, eight of the identified DEGs (sor, cbl, ompA, atpF, nuoH, nuoC, sqr, grxB) were verified as being related to the acid stress response process. This study contributes toward expanding the application of these acidophiles in industrial bioleaching.
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Acidithiobacillus , Matriz Extracelular de Sustancias Poliméricas , Acidithiobacillus/genética , Azufre , TranscriptomaRESUMEN
In this study, a one-step extrusion method is proposed to prepare blended polylactic acid (PLA)/thermoplastic starch (TPS) using a novel plant-derived compatibilizer, pyrogallic acid (PGA), to enhance the PLA/TPS compatibility. The effects of PGA on the mechanical behavior, fractured cross-section morphology, thermal and dynamic mechanical performance, and water resistance of PLA/TPS blends were systematically studied. Results demonstrate that the addition of PGA effectively improves the compatibility between TPS and PLA, resulting in enhanced tensile strength, crystallinity, elongation at break, thermal stability, and hydrophobicity of the blends. Specifically, incorporating 1.5 phr of PGA into the blend system yields the highest values for tensile strength (23.38 MPa) and elongation at break (16.96 %), which are 24.7 % and 233.2 %, respectively, higher than those observed for pure PLA/TPS blends. Furthermore, other properties exhibit obvious improvements upon incorporation of PGA into the blends. This approach provides a promising strategy for enhancing the performance of PLA/TPS blends and expanding their applications in food packaging, agricultural film, etc.
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Poliésteres , Almidón , Resistencia a la Tracción , Almidón/química , Poliésteres/química , Interacciones Hidrofóbicas e Hidrofílicas , Temperatura , Agua/químicaRESUMEN
Background: Retroperitoneal fibrosis, a condition of uncertain origin, is rarely linked to 8% of malignant cases, including breast, lung, gastrointestinal, genitourinary, thyroid, and carcinoid. The mechanism leading to peritoneal fibrosis induced by tumors is not well understood, possibly encompassing direct infiltration of neoplastic cells or the initiation of inflammatory responses prompted by cytokines released by tumor cells. We report a case of breast cancer with renal metastasis and retroperitoneal fibrosis detected using 18F-FDG PET/CT, providing help for clinical diagnosis and treatment. Case report: A 49-year-old woman was referred to the hospital with elevated creatinine and oliguria for over a month. Abdominal computer tomography (CT) and magnetic resonance imaging (MRI) showed a retroperitoneal fibrosis-induced acute kidney injury (AKI) was suspected. However, a percutaneous biopsy of the kidney lesion confirmed metastasis from breast cancer. The physical examination revealed inverted nipples and an orange peel appearance on the skin of both breasts. Ultrasonography revealed bilateral hyperplasia (BIRADS 4a) of the mammary glands and bilateral neck and axillary lymphadenopathy. Subsequently, 18F-deoxyglucose positron emission tomography/computer tomography (18F-FDG PET/CT) detected abnormally high uptake (SUVmax) in the bilateral mammary glands and axillary lymph nodes, suggesting bilateral breast cancer. Furthermore, abnormal 18F-FDG uptake was detected in the kidney, suggesting renal metastasis. In addition, abnormal 18F-FDG uptake was observed in the vertebrae, accompanied by an elevation in inhomogeneous bone mineral density, raising suspicion of bone metastases. However, the possibility of myelodysplasia cannot be dismissed, and further investigations will be conducted during close follow-ups. There was significant 18F-FDG uptake in the retroperitoneal position indicating a potential association between retroperitoneal fibrosis and breast cancer. The final pathological diagnosis of the breast tissue confirmed bilateral invasive ductal carcinoma. The patient had been treated with 11 cycles of albumin-bound (nab)-paclitaxel (0.3 mg) and had no significant adverse reaction. Conclusion: In this case, neither the bilateral breast cancer nor the kidney metastatic lesion showed typical nodules or masses, so breast ultrasound, abdominal CT, and MRI did not suggest malignant lesions. PET/CT played an important role in detecting occult metastases and primary lesions, thereby contributing to more accurate staging, monitoring treatment responses, and prediction of prognosis in breast cancer.
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Background: Low-grade fibromyxoid sarcoma (LGFMS) is a rare type of soft tissue sarcoma that often involves the deep soft tissue of the extremities and trunk in young and middle-aged adults. It is uncommon in the elderly. Here we discuss a case of LGFMS in an elderly patient who had recurrence and metastasis within 2 years of resection of the primary tumor. Case report: A 71-year-old LGFMS patient was presented with a mass in the left forearm accompanied by pain and numbness from the left upper arm to fingers. The patient subsequently underwent 3 surgical resections, although she had 3 recurrences within 6 months after the initial diagnosis. Considering the malignant biological behavior of the tumor, an amputation at 5 cm above the elbow was eventually performed. However, recurrence in the extremity of the stump and chest wall metastasis were observed 2 years after amputation. Then resection of the metastases, radiotherapy and particle implantation therapy were performed. The patient is currently undergoing follow-up and has no evidence of recurrence. Conclusion: In our case, multiple early postoperative recurrences may be associated with a positive margin at initial operation. The patient underwent a total of 5 operations including local resection of the primary tumor, twice wide resections, amputation and metastatic surgery with 4 early postoperative recurrences and metastases within 4 years, suggesting that LGFMS may have highly invasive biological behavior. Our case demonstrated that early aggressive surgical treatment is recommended for LGFMS patients with a positive margin at initial operation and patients who had recurrence even after wide resection rather than local resection. Further research is needed to develop more effective treatment options for rapidly progress and highly aggressive LGFMS.
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Background: One of the exceptionally rare forms of non-Hodgkin's lymphoma (NHL) is primary cardiac lymphoma (PCL). The principal clinical manifestation in patients with PCL involves cardiac symptoms resulting from myocardial infiltration by lymphoma, including arrhythmias, heart failure, and chest pain. 18F-FDG PET/CT serves as a reliable and indispensable imaging modality for assessing clinically staging NHL. Case report: We present a rare case involving a 72-year-old woman diagnosed with primary intracardiac diffuse large B-cell lymphoma. For further staging, the patient underwent 18F-FDG PET/CT, revealing multiple nodular soft tissue density lesions in the heart and pericardium exhibiting increased FDG metabolism (SUVmax = 12.1). The supradiaphragmatic and infradiaphragmatic segments of the inferior vena cava exhibited irregular morphology with localized nodular changes and increased FDG metabolism in the surrounding area (SUVmax = 9.7). Additionally, multiple enlarged lymph nodes were identified in the left axilla, mediastinum, and adjacent to the abdominal aorta, displaying heterogeneous FDG uptake with an SUVmax of 9.3, indicating lymphoma involvement. The above imaging findings suggested that the mass was a PCL. Hence, the patient underwent a combination of chemotherapy and immunotherapy using R-CDOP (rituximab, cyclophosphamide, liposomal doxorubicin, vincristine, and prednisone). Following two courses of treatment within a span of 2 months, there was a partial remission observed in the cardiac lymphoma and the enlarged lymph nodes. Conclusion: The case elucidated in this report contributes to an enhanced understanding of the disease for clinicians, with 18F-FDG PET/CT providing comprehensive insights into the extent of cardiac involvement, as well as the engagement of extracardiac organs and pathologic lymph nodes. The 18F-FDG PET/CT examination not only visually delineates the lesion's location and extent but also serves as a cornerstone for clinical tumor staging, offering valuable support for treatment monitoring and subsequent follow-up.
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AIMS: Cognitive dysfunction associated with chronic pain may be caused by impaired synaptic plasticity. Considering the impact of silent information regulator 1 (SIRT1) on synaptic plasticity, we explored the exact role of SIRT1 in cognitive impairment caused by chronic pain. METHODS: We evaluated the memory ability of mice with the fear conditioning test (FCT) after spared nerve injury (SNI) model. Western blotting and immunofluorescence were used to analyze the expression levels of SIRT1. Hippocampal synaptic plasticity was detected with Golgi staining, transmission electron microscopy, and long-term potentiation (LTP). In the intervention study, AAV9-CaMKIIα-Cre-EGFP was injected to SIRT1flox/flox mice to knockdown the expression levels of SIRT1. Besides, SNI mice were injected with AAV2/9-CaMKIIα-SIRT1-3*Flag-GFP or SRT1720 to increase the expression levels or enzymatic activity of SIRT1. RESULTS: Our current results indicated that cognitive function in SNI mice was impaired, SIRT1 expression in glutaminergic neurons in the hippocampal CA1 area was downregulated, and synaptic plasticity was altered. Selective knockdown of SIRT1 in hippocampus damaged synaptic plasticity and cognitive function of healthy mice. In addition, the impaired synaptic plasticity and cognitive dysfunction of SNI mice could be improved by the upregulation of SIRT1 expression or enzyme activity. CONCLUSIONS: Reduced SIRT1 expression in hippocampus of SNI mice may induce cognitive impairment associated with chronic pain by mediating the impaired synaptic plasticity.
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Dolor Crónico , Disfunción Cognitiva , Animales , Ratones , Disfunción Cognitiva/genética , Disfunción Cognitiva/metabolismo , Regulación hacia Abajo , Hipocampo/metabolismo , Plasticidad Neuronal/fisiología , Sirtuina 1/genética , Sirtuina 1/metabolismoRESUMEN
The full mechanism of action of propofol, a commonly administered intravenous anesthetic drug in clinical practice, remains elusive. The focus of this study was the role of GABAergic neurons which are the main neuron group in the ventral pallidum (VP) closely associated with anesthetic effects in propofol anesthesia. The activity of VP GABAergic neurons following propofol anesthesia in Vgat-Cre mice was observed via detecting c-Fos immunoreactivity by immunofluorescence and western blotting. Subsequently, chemogenetic techniques were employed in Vgat-Cre mice to regulate the activity of VP GABAergic neurons. The role of VP GABAergic neurons in generating the effects of general anesthesia induced by intravenous propofol was further explored through behavioral tests of the righting reflex. The results revealed that c-Fos expression in VP GABAergic neurons in Vgat-Cre mice dramatically decreased after propofol injection. Further studies demonstrated that chemogenetic activation of VP GABAergic neurons during propofol anesthesia shortened the duration of anesthesia and promoted wakefulness. Conversely, the inhibition of VP GABAergic neurons extended the duration of anesthesia and facilitated the effects of anesthesia. The results obtained in this study suggested that regulating the activity of GABAergic neurons in the ventral pallidum altered the effect of propofol on general anesthesia.
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Anestesia General , Anestésicos Intravenosos , Prosencéfalo Basal , Neuronas GABAérgicas , Propofol , Propofol/farmacología , Neuronas GABAérgicas/efectos de los fármacos , Neuronas GABAérgicas/metabolismo , Animales , Prosencéfalo Basal/efectos de los fármacos , Anestésicos Intravenosos/farmacología , Anestesia General/métodos , Ratones , Masculino , Ratones Transgénicos , Proteínas Proto-Oncogénicas c-fos/metabolismo , Reflejo de Enderezamiento/efectos de los fármacos , Reflejo de Enderezamiento/fisiología , Vigilia/efectos de los fármacos , Vigilia/fisiología , Ratones Endogámicos C57BL , Proteínas del Transporte Vesicular de Aminoácidos InhibidoresRESUMEN
The mechanism of ketamine-induced neurotoxicity development remains elusive. Mitochondrial fusion/fission dynamics play a critical role in regulating neurogenesis. Therefore, this study was aimed to evaluate whether mitochondrial dynamics were involved in ketamine-induced impairment of neurogenesis in neonatal rats and long-term synaptic plasticity dysfunction. In the in vivo study, postnatal day 7 (PND-7) rats received intraperitoneal (i.p.) injection of 40 mg/kg ketamine for four consecutive times at 1 h intervals. The present findings revealed that ketamine induced mitochondrial fusion dysfunction in hippocampal neural stem cells (NSCs) by downregulating Mitofusin 2 (Mfn2) expression. In the in vitro study, ketamine treatment at 100 µM for 6 h significantly decreased the Mfn2 expression, and increased ROS generation, decreased mitochondrial membrane potential and ATP levels in cultured hippocampal NSCs. For the interventional study, lentivirus (LV) overexpressing Mfn2 (LV-Mfn2) or control LV vehicle was microinjected into the hippocampal dentate gyrus (DG) 4 days before ketamine administration. Targeted Mfn2 overexpression in the DG region could restore mitochondrial fusion in NSCs and reverse the inhibitory effect of ketamine on NSC proliferation and its faciliatory effect on neuronal differentiation. In addition, synaptic plasticity was evaluated by transmission electron microscopy, Golgi-Cox staining and long-term potentiation (LTP) recordings at 24 h after the end of the behavioral test. Preconditioning with LV-Mfn2 improved long-term cognitive dysfunction after repeated neonatal ketamine exposure by reversing the inhibitory effect of ketamine on synaptic plasticity in the hippocampal DG. The present findings demonstrated that Mfn2-mediated mitochondrial fusion dysfunction plays a critical role in the impairment of long-term neurocognitive function and synaptic plasticity caused by repeated neonatal ketamine exposure by interfering with hippocampal neurogenesis. Thus, Mfn2 might be a novel therapeutic target for the prevention of the developmental neurotoxicity of ketamine.
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Animales Recién Nacidos , Cognición , GTP Fosfohidrolasas , Hipocampo , Ketamina , Dinámicas Mitocondriales , Células-Madre Neurales , Neurogénesis , Ratas Sprague-Dawley , Animales , Masculino , Ratas , Anestesia/efectos adversos , Cognición/efectos de los fármacos , GTP Fosfohidrolasas/metabolismo , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Hipocampo/patología , Ketamina/administración & dosificación , Ketamina/efectos adversos , Ketamina/toxicidad , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Dinámicas Mitocondriales/efectos de los fármacos , Proteínas Mitocondriales , Células-Madre Neurales/efectos de los fármacos , Células-Madre Neurales/metabolismo , Neurogénesis/efectos de los fármacos , Plasticidad Neuronal/efectos de los fármacosRESUMEN
B-cell maturation antigen (BCMA) has emerged as a promising tumor marker for the diagnosis and treatment of multiple myeloma. The noninvasive and rapid detection of BCMA expression in vivo provides significant value in screening and evaluating multiple myeloma patients receiving BCMA-targeted therapy. We identified the BCMA-targeting peptide BP1 from a one-bead-one-compound (OBOC) peptide library using a high-throughput microarray strategy. The BCMA-targeting specificity and affinity of BP1 were assessed by surface plasmon resonance imaging (SPRi), flow cytometry, and confocal imaging. BCMA-positive (H929) and BCMA-negative (K562) subcutaneous tumor models were established and labeled with 68Ga for BP1, followed by PET imaging and biodistribution studies. PET imaging demonstrated that 68Ga-labeled BP1 has significant specific uptake in multiple myeloma, enabling rapid identification of BCMA expression and precise delineation of the disease. Thus, BP1 represents an ideal candidate for multiple myeloma imaging.
RESUMEN
AIM: Repeated exposure to ketamine during the neonatal period in mice leads to cognitive impairments in adulthood. These impairments are likely caused by synaptic plasticity and excitability damage. We investigated the precise role of brain-derived neurotrophic factor (BDNF) in the cognitive impairments induced by repeated ketamine exposure during the neonatal period. METHODS: We evaluated the cognitive function of mice using the Morris water maze test and novel object recognition test. Western blotting and immunofluorescence were used to detect the protein levels of BDNF. Western blotting, Golgi-Cox staining, transmission electron microscopy, and long-term potentiation (LTP) recordings were used to assess synaptic plasticity in the hippocampus. The excitability of neurons was evaluated using c-Fos. In the intervention experiment, pAdeno-CaMKIIα-BDNF-mNeuronGreen was injected into the hippocampal CA1 region of mice to increase the level of BDNF. The excitability of neurons was enhanced using a chemogenetic approach. RESULTS: Our findings suggest that cognitive impairments in mice repeatedly exposed to ketamine during the neonatal period are associated with downregulated BDNF protein level, synaptic plasticity damage, and decreased excitability of glutamatergic neurons in the hippocampal CA1 region. Furthermore, the specific upregulation of BDNF in glutamatergic neurons of the hippocampal CA1 region and the enhancement of excitability can improve impaired synaptic plasticity and cognitive function in mice. CONCLUSION: BDNF downregulation mediates synaptic plasticity and excitability damage, leading to cognitive impairments in adulthood following repeated ketamine exposure during the neonatal period.
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Disfunción Cognitiva , Ketamina , Ratones , Animales , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Ketamina/toxicidad , Regulación hacia Abajo , Plasticidad Neuronal/fisiología , Hipocampo/metabolismo , Neuronas/metabolismo , Disfunción Cognitiva/metabolismoRESUMEN
ABSTRACT: Pancreatic choriocarcinoma is a rare disease, and concurrent hepatic metastases have not previously been reported. We report a case of a 46-year-old woman with significantly elevated human chorionic gonadotropin ß levels, and 18 F-FDG PET/CT demonstrated FDG-avid lesions in the pancreatic head, liver, and lymph nodes. The initial diagnosis of pancreatic choriocarcinoma with metastases was made and further confirmed by PET/CT-guided biopsy. 125 I seeds were then implanted to treat the pancreatic choriocarcinoma lesions, which effectively reduced the tumor size. New hepatic metastases have been observed after 5 months, and this case had an overall survival of 10 months.