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1.
Cell ; 185(10): 1694-1708.e19, 2022 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-35447074

RESUMO

Immunotherapy is a promising treatment for triple-negative breast cancer (TNBC), but patients relapse, highlighting the need to understand the mechanisms of resistance. We discovered that in primary breast cancer, tumor cells that resist T cell attack are quiescent. Quiescent cancer cells (QCCs) form clusters with reduced immune infiltration. They also display superior tumorigenic capacity and higher expression of chemotherapy resistance and stemness genes. We adapted single-cell RNA-sequencing with precise spatial resolution to profile infiltrating cells inside and outside the QCC niche. This transcriptomic analysis revealed hypoxia-induced programs and identified more exhausted T cells, tumor-protective fibroblasts, and dysfunctional dendritic cells inside clusters of QCCs. This uncovered differential phenotypes in infiltrating cells based on their intra-tumor location. Thus, QCCs constitute immunotherapy-resistant reservoirs by orchestrating a local hypoxic immune-suppressive milieu that blocks T cell function. Eliminating QCCs holds the promise to counteract immunotherapy resistance and prevent disease recurrence in TNBC.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Imunossupressores/uso terapêutico , Imunoterapia , Recidiva Local de Neoplasia , Linfócitos T/patologia , Neoplasias de Mama Triplo Negativas/patologia , Microambiente Tumoral
2.
Cell ; 180(1): 107-121.e17, 2020 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-31866069

RESUMO

Fibrosis can develop in most organs and causes organ failure. The most common type of lung fibrosis is known as idiopathic pulmonary fibrosis, in which fibrosis starts at the lung periphery and then progresses toward the lung center, eventually causing respiratory failure. Little is known about the mechanisms underlying the pathogenesis and periphery-to-center progression of the disease. Here we discovered that loss of Cdc42 function in alveolar stem cells (AT2 cells) causes periphery-to-center progressive lung fibrosis. We further show that Cdc42-null AT2 cells in both post-pneumonectomy and untreated aged mice cannot regenerate new alveoli, resulting in sustained exposure of AT2 cells to elevated mechanical tension. We demonstrate that elevated mechanical tension activates a TGF-ß signaling loop in AT2 cells, which drives the periphery-to-center progression of lung fibrosis. Our study establishes a direct mechanistic link between impaired alveolar regeneration, mechanical tension, and progressive lung fibrosis.


Assuntos
Células-Tronco Adultas/metabolismo , Fibrose Pulmonar Idiopática/etiologia , Alvéolos Pulmonares/metabolismo , Células-Tronco Adultas/patologia , Idoso , Células Epiteliais Alveolares/patologia , Animais , Fenômenos Biomecânicos/fisiologia , Feminino , Fibrose/patologia , Humanos , Fibrose Pulmonar Idiopática/metabolismo , Fibrose Pulmonar Idiopática/patologia , Pulmão/patologia , Masculino , Camundongos , Pessoa de Meia-Idade , Alvéolos Pulmonares/patologia , Regeneração , Transdução de Sinais , Células-Tronco/patologia , Estresse Mecânico , Estresse Fisiológico/fisiologia , Fator de Crescimento Transformador beta/metabolismo , Proteína cdc42 de Ligação ao GTP/genética , Proteína cdc42 de Ligação ao GTP/metabolismo
4.
Development ; 151(20)2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38572957

RESUMO

The ovarian microenvironment plays a crucial role in ensuring the reproductive success of viviparous teleosts. However, the molecular mechanism underlying the interaction between spermatozoa and the ovarian microenvironment has remained elusive. This study aimed to contribute to a better understanding of this process in black rockfish (Sebastes schlegelii) using integrated multi-omics approaches. The results demonstrated significant upregulation of ovarian complement-related proteins and pattern recognition receptors, along with remodeling of glycans on the surface of spermatozoa at the early spermatozoa-storage stage (1 month after mating). As spermatozoa were stored over time, ovarian complement proteins were progressively repressed by tryptophan and hippurate, indicating a remarkable adaptation of spermatozoa to the ovarian microenvironment. Before fertilization, a notable upregulation of cellular junction proteins was observed. The study revealed that spermatozoa bind to ZPB2a protein through GSTM3 and that ZPB2a promotes spermatozoa survival and movement in a GSTM3-dependent manner. These findings shed light on a key mechanism that influences the dynamics of spermatozoa in the female reproductive tract, providing valuable insights into the molecular networks regulating spermatozoa adaptation and survival in species with internal fertilization.


Assuntos
Ovário , Espermatozoides , Animais , Masculino , Feminino , Espermatozoides/metabolismo , Ovário/metabolismo , Fertilização , Viviparidade não Mamífera , Proteômica , Proteínas de Peixes/metabolismo , Proteínas de Peixes/genética , Peixes/metabolismo , Microambiente Celular , Multiômica
5.
Cell ; 148(1-2): 244-58, 2012 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-22265415

RESUMO

p53 is a frequent target for mutation in human tumors, and mutant p53 proteins can actively contribute to tumorigenesis. We employed a three-dimensional culture model in which nonmalignant breast epithelial cells form spheroids reminiscent of acinar structures found in vivo, whereas breast cancer cells display highly disorganized morphology. We found that mutant p53 depletion is sufficient to phenotypically revert breast cancer cells to a more acinar-like morphology. Genome-wide expression analysis identified the mevalonate pathway as significantly upregulated by mutant p53. Statins and sterol biosynthesis intermediates reveal that this pathway is both necessary and sufficient for the phenotypic effects of mutant p53 on breast tissue architecture. Mutant p53 associates with sterol gene promoters at least partly via SREBP transcription factors. Finally, p53 mutation correlates with highly expressed sterol biosynthesis genes in human breast tumors. These findings implicate the mevalonate pathway as a therapeutic target for tumors bearing mutations in p53.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Ácido Mevalônico/metabolismo , Proteína Supressora de Tumor p53/genética , Linhagem Celular Tumoral , Feminino , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Redes e Vias Metabólicas/efeitos dos fármacos , Mutação , Prenilação , Regiões Promotoras Genéticas , Sinvastatina/farmacologia , Proteínas de Ligação a Elemento Regulador de Esterol/metabolismo
6.
Blood ; 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38701407

RESUMO

Glucocorticoids are key components of the current standard-of-care regimens (e.g., R-CHOP, EPOCH-R, Hyper-CVAD) for treatment of B-cell malignancy. However, systemic glucocorticoid treatment is associated with several adverse events. CD19 displays restricted expression in normal B-cells and is up-regulated in B-cell malignancies. ABBV-319 is a CD19-targeting antibody-drug conjugate (ADC) engineered to reduce glucocorticoid-associated toxicities while possessing three distinct mechanisms of action (MOA) to increase therapeutic efficacy: (1) antibody-mediated delivery of glucocorticoid receptor modulator (GRM) payload to activate apoptosis, (2) inhibition of CD19 signaling, and (3) enhanced Fc-mediated effector function via afucosylation of the antibody backbone. ABBV-319 elicited potent GRM-driven anti-tumor activity against multiple malignant B-cell lines in vitro as well as in cell line-derived xenografts (CDXs) and patient-derived xenografts (PDXs) in vivo. Remarkably, a single-dose of ABBV-319 induced sustained tumor regression and enhanced anti-tumor activity compared to repeat dosing of systemic prednisolone at the maximum tolerated dose (MTD) in mice. The unconjugated CD19 monoclonal antibody (mAb) also displayed anti-proliferative activity on a subset of B-cell lymphoma cell lines through the inhibition of PI3K signaling. Moreover, afucosylation of the CD19 mAb enhanced Fc-mediated antibody-dependent cellular cytotoxicity (ADCC), and this activity was maintained after conjugation with GRM payloads. Notably, ABBV-319 displayed superior efficacy compared to afucosylated CD19 mAb in human CD34+ PBMC-engrafted NSG-tg(Hu-IL15) transgenic mice, demonstrating enhanced anti-tumor activity when multiple MOAs are enabled. ABBV-319 also showed durable anti-tumor activity across multiple B-cell lymphoma PDX models, including non-germinal center B-cell (GCB) DLBCL and relapsed lymphoma post R-CHOP treatment. Collectively, these data support the ongoing evaluation of ABBV-319 in Phase I clinical trial (NCT05512390).

7.
J Immunol ; 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39058321

RESUMO

IFN regulatory factors (IRFs) are transcription factors that mediate homeostatic mechanisms of host defense against pathogens. In addition to IRF1-9, which are conserved across vertebrates, teleost fishes have two other IRFs, IRF10 and IRF11. In zebrafish (Danio rerio), IRF10 represses the expression of IFNφ1 and IFNφ3, whereas IRF11 exerts the opposite effect. In this study, we found IRF10 could significantly inhibit the expression of IFNφ1 and IFNφ3 induced by IFN11 to synergistically regulate type I IFN expression. To clarify the synergistically regulatory mechanism of IRF10 and IRF11 in type I IFN expression, we determined and analyzed the crystal structures of the DNA-binding domains (DBDs) of zebrafish IRF10 and IRF11 bound to DNA, as well as IRF11 DBD in apo form. The interactions of IRF10-DBD and IRF11-DBD with DNA backbone were elaborated in detail. Further analysis showed that IRF10 and IRF11 have the same binding patterns and comparable affinities with the IFN-sensitive response elements of IFNφ1 and IFNφ3 promoters. Therefore, IRF10 could function as a controlling factor for IRF11 by competitive binding of the IFN-sensitive response elements to coregulate the host IFN response. Accordingly, similar to IRF1 and IRF2 in mammals, IRF10 and IRF11 act as another pair of negative and positive regulators to balance the antiviral responses in fish.

8.
Biochemistry ; 63(9): 1225-1233, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38682295

RESUMO

As plant photoreceptors, phytochromes are capable of detecting red light and far-red light, thereby governing plant growth. All2699 is a photoreceptor found in Nostoc sp. PCC7120 that specifically responds to red light and far-red light. All2699g1g2 is a truncated protein carrying the first and second GAF (cGMP phosphodiesterase/adenylyl cyclase/FhlA) domains of All2699. In this study, we found that, upon exposure to red light, the protein underwent aggregation, resulting in the formation of protein aggregates. Conversely, under far-red light irradiation, these protein aggregates dissociated. We delved into the factors that impact the aggregation of All2699g1g2, focusing on the protein structure. Our findings showed that the GAF2 domain contains a low-complexity (LC) loop region, which plays a crucial role in mediating protein aggregation. Specifically, phenylalanine at position 239 within the LC loop region was identified as a key site for the aggregation process. Furthermore, our research revealed that various factors, including irradiation time, temperature, concentration, NaCl concentration, and pH value, can impact the aggregation of All2699g1g2. The aggregation led to variations in Pfr concentration depending on temperature, NaCl concentration, and pH value. In contrast, ΔLC did not aggregate and therefore lacked responses to these factors. Consequently, the LC loop region of All2699g1g2 extended and enhanced sensory properties.


Assuntos
Proteínas de Bactérias , Luz , Nostoc , Nostoc/metabolismo , Nostoc/química , Nostoc/efeitos da radiação , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Domínios Proteicos , Agregados Proteicos , Fotorreceptores Microbianos/química , Fotorreceptores Microbianos/metabolismo , Pigmentos Biliares/química , Pigmentos Biliares/metabolismo , Concentração de Íons de Hidrogênio , Fitocromo/química , Fitocromo/metabolismo
9.
J Am Chem Soc ; 146(18): 12485-12495, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38651836

RESUMO

Understanding the mechanisms of C-H activation of alkanes is a very important research topic. The reactions of metal clusters with alkanes have been extensively studied to reveal the electronic features governing C-H activation, while the experimental cluster reactivity was qualitatively interpreted case by case in the literature. Herein, we prepared and mass-selected over 100 rhodium-based clusters (RhxVyOz- and RhxCoyOz-) to react with light alkanes, enabling the determination of reaction rate constants spanning six orders of magnitude. A satisfactory model being able to quantitatively describe the rate data in terms of multiple cluster electronic features (average electron occupancy of valence s orbitals, the minimum natural charge on the metal atom, cluster polarizability, and energy gap involved in the agostic interaction) has been constructed through a machine learning approach. This study demonstrates that the general mechanisms governing the very important process of C-H activation by diverse metal centers can be discovered by interpreting experimental data with artificial intelligence.

10.
Biochem Biophys Res Commun ; 711: 149906, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38640879

RESUMO

Cardiovascular diseases (CVD) represent one of the most considerable global health threats, owing to their high incidence and mortality rates. Despite the ongoing advancements in detection, prevention, treatment, and prognosis of CVD, which have resulted in a decline in both incidence and mortality rates, CVD remains a major public health concern. Therefore, novel diagnostic biomarkers and therapeutic interventions are imperative to minimise the risk of CVD. Non-coding RNAs (ncRNAs) have recently gained increasing attention, with PIWI-interacting RNAs (piRNAs) emerging as a class of small ncRNAs traditionally recognised for their role in silencing transposons within cells. Although the functional roles of PIWI proteins and piRNAs in human cells remain unclear, growing evidence suggests that these molecules are gradually becoming valuable biomarkers for the diagnosis and treatment of CVD. This review provides a comprehensive summary of the latest studies on piRNAs in CVD. This review discusses the roles of piRNAs in various cardiovascular subtypes, including myocardial hypertrophy, heart failure, myocardial infarction, and cardiac regeneration. The perceived insights may contribute novel perspectives for the diagnosis and treatment of CVD.


Assuntos
Biomarcadores , Doenças Cardiovasculares , RNA Interferente Pequeno , Humanos , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/diagnóstico , Biomarcadores/metabolismo , RNA Interferente Pequeno/metabolismo , RNA Interferente Pequeno/genética , Animais , RNA de Interação com Piwi
11.
Biochem Biophys Res Commun ; 733: 150350, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-39053107

RESUMO

Postovulatory aging of oocytes involves a series of deleterious molecular and cellular changes, which adversely affect oocyte maturation, fertilization, and early embryonic development. Petunidin-3-O-(6-O-pcoumaroyl)-rutinoside-5-O-glucoside (PrG), the main active ingredient of anthocyanin, exerts antioxidant effects. This study investigated whether PrG supplementation could delay postovulatory oocyte aging by alleviating oxidative stress. Our results showed that PrG supplementation decreased the number of abnormal morphology oocytes and improved the oxidative stress of aged oocytes by facilitating the reduction of the reactive oxygen species, the increase in glutathione content, and the recovery of expression of antioxidant-related gene expression. In addition, PrG treatment recovered mitochondrial dysfunction, including mitochondrial distribution, mitochondrial membrane potential and adenosine triphosphate in aged oocytes. PrG-treated oocytes returned to normal levels of cytoplasmic and mitochondrial calcium. Notably, PrG inhibited early apoptosis in aged oocytes. RNA-seq and qRT-PCR results revealed that PrG ameliorated oxidative stress injury in postovulatory aging oocytes of mice via the putrescine pathway. In conclusion, in vitro PrG supplementation is a potential therapy for delaying postovulatory oocyte aging.

12.
Small ; : e2404347, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958084

RESUMO

Solar-driven interfacial evaporation is an efficient method for purifying contaminated or saline water. Nonetheless, the suboptimal design of the structure and composition still necessitates a compromise between evaporation rate and service life. Therefore, achieving efficient production of clean water remains a key challenge. Here, a biomimetic dictyophora hydrogel based on loofah/carbonized sucrose@ZIF-8/polyvinyl alcohol is demonstrated, which can serve as an independent solar evaporator for clean water recovery. This special structural design achieves effective thermal positioning and minimal heat loss, while reducing the actual enthalpy of water evaporation. The evaporator achieves a pure water evaporation rate of 3.88 kg m-2 h-1 and a solar-vapor conversion efficiency of 97.16% under 1 sun irradiation. In comparison, the wastewater evaporation rate of the evaporator with ZIF-8 remains at 3.85 kg m-2 h-1 for 30 days, which is 16.3% higher than the light irradiation without ZIF-8. Equally important, the evaporator also showcases the capability to cleanse water from diverse sources of contaminants, including those with small molecules, oil, heavy metal ions, and bacteria, greatly improving the lifespan of the evaporator.

13.
Small ; 20(14): e2306402, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37992239

RESUMO

Photodynamic therapy (PDT) is extensively investigated for tumor therapy in the clinic. However, the efficacy of PDT is severely limited by the tissue penetrability of light, short effective half-life and radius of reactive oxygen species (ROS), and the weak immunostimulatory effect. In this study, a glutathione (GSH)-activatable nano-photosensitizer is developed to load with arachidonic acid (AA) and camouflage by erythrocyte membrane, which serves as a laser-ignited lipid peroxidation nanoamplifier (MAR). The photosensitive effect of MAR is recovered accompanied by the degradation in the tumor microenvironment and triggers the peroxidation of AA upon laser excitation. Interestingly, it aggravates the propagation of ferroptosis among cancer cells by driving the continuous lipid peroxidation chain reactions with the participation of the degradation products, ferrous ions (Fe2+), and AA. Consequently, even the deep-seated tumor cells without illumination also undergo ferroptosis owing to the propagation of ferroptotic signal. Moreover, the residual tumor cells undergoing ferroptosis still maintain high immunogenicity after PDT, thus continuously triggering sufficient tumor-associated antigens (TAAs) release to remarkably promote the anti-tumor immune response. Therefore, this study will provide a novel "all-in-one" nano-photosensitizer that not only amplifies the damaging effect and expands the effective range of PDT but also improves the immunostimulatory effect after PDT.


Assuntos
Fotoquimioterapia , Fármacos Fotossensibilizantes , Peroxidação de Lipídeos , Fármacos Fotossensibilizantes/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Glutationa/metabolismo , Linhagem Celular Tumoral
14.
J Virol ; 97(4): e0182922, 2023 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-36943056

RESUMO

Spring viremia of carp virus (SVCV) is a highly pathogenic Vesiculovirus infecting the common carp, yet neither a vaccine nor effective therapies are available to treat spring viremia of carp (SVC). Like all negative-sense viruses, SVCV contains an RNA genome that is encapsidated by the nucleoprotein (N) in the form of a ribonucleoprotein (RNP) complex, which serves as the template for viral replication and transcription. Here, the three-dimensional (3D) structure of SVCV RNP was resolved through cryo-electron microscopy (cryo-EM) at a resolution of 3.7 Å. RNP assembly was stabilized by N and C loops; RNA was wrapped in the groove between the N and C lobes with 9 nt nucleotide per protomer. Combined with mutational analysis, our results elucidated the mechanism of RNP formation. The RNA binding groove of SVCV N was used as a target for drug virtual screening, and it was found suramin had a good antiviral effect. This study provided insights into RNP assembly, and anti-SVCV drug screening was performed on the basis of this structure, providing a theoretical basis and efficient drug screening method for the prevention and treatment of SVC. IMPORTANCE Aquaculture accounts for about 70% of global aquatic products, and viral diseases severely harm the development of aquaculture industry. Spring viremia of carp virus (SVCV) is the pathogen causing highly contagious spring viremia of carp (SVC) disease in cyprinids, especially common carp (Cyprinus carpio), yet neither a vaccine nor effective therapies are available to treat this disease. In this study, we have elucidated the mechanism of SVCV ribonucleoprotein complex (RNP) formation by resolving the 3D structure of SVCV RNP and screened antiviral drugs based on the structure. It is found that suramin could competitively bind to the RNA binding groove and has good antiviral effects both in vivo and in vitro. Our study provides a template for rational drug discovery efforts to treat and prevent SVCV infections.


Assuntos
Modelos Moleculares , Rhabdoviridae , Ribonucleoproteínas , Proteínas Virais , Ribonucleoproteínas/química , Ribonucleoproteínas/metabolismo , Rhabdoviridae/química , Rhabdoviridae/efeitos dos fármacos , Proteínas Virais/química , Proteínas Virais/metabolismo , Estrutura Quaternária de Proteína , Antivirais/farmacologia , Avaliação Pré-Clínica de Medicamentos , Microscopia Crioeletrônica , Suramina/farmacologia
15.
Cardiovasc Diabetol ; 23(1): 243, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38987779

RESUMO

BACKGROUND: The prevalence of obesity-associated insulin resistance (IR) is increasing along with the increase in obesity rates. In this study, we compared the predictive utility of four alternative indexes of IR [triglyceride glucose index (TyG index), metabolic score for insulin resistance (METS-IR), the triglyceride/high-density lipoprotein cholesterol (TG/HDL-C) ratio and homeostatic model assessment of insulin resistance (HOMA-IR)] for all-cause mortality and cardiovascular mortality in the general population based on key variables screened by the Boruta algorithm. The aim was to find the best replacement index of IR. METHODS: In this study, 14,653 participants were screened from the National Health and Nutrition Examination Survey (2001-2018). And TyG index, METS-IR, TG/HDL-C and HOMA-IR were calculated separately for each participant according to the given formula. The predictive values of IR replacement indexes for all-cause mortality and cardiovascular mortality in the general population were assessed. RESULTS: Over a median follow-up period of 116 months, a total of 2085 (10.23%) all-cause deaths and 549 (2.61%) cardiovascular disease (CVD) related deaths were recorded. Multivariate Cox regression and restricted cubic splines analysis showed that among the four indexes, only METS-IR was significantly associated with both all-cause and CVD mortality, and both showed non-linear associations with an approximate "U-shape". Specifically, baseline METS-IR lower than the inflection point (41.33) was negatively associated with mortality [hazard ratio (HR) 0.972, 95% CI 0.950-0.997 for all-cause mortality]. In contrast, baseline METS-IR higher than the inflection point (41.33) was positively associated with mortality (HR 1.019, 95% CI 1.011-1.026 for all-cause mortality and HR 1.028, 95% CI 1.014-1.043 for CVD mortality). We further stratified the METS-IR and showed that significant associations between METS-IR levels and all-cause and cardiovascular mortality were predominantly present in the nonelderly population aged < 65 years. CONCLUSIONS: In conjunction with the results of the Boruta algorithm, METS-IR demonstrated a more significant association with all-cause and cardiovascular mortality in the U.S. population compared to the other three alternative IR indexes (TyG index, TG/HDL-C and HOMA-IR), particularly evident in individuals under 65 years old.


Assuntos
Biomarcadores , Glicemia , Doenças Cardiovasculares , Causas de Morte , Resistência à Insulina , Síndrome Metabólica , Inquéritos Nutricionais , Valor Preditivo dos Testes , Triglicerídeos , Humanos , Masculino , Feminino , Doenças Cardiovasculares/mortalidade , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/sangue , Pessoa de Meia-Idade , Medição de Risco , Adulto , Estados Unidos/epidemiologia , Biomarcadores/sangue , Idoso , Triglicerídeos/sangue , Prognóstico , Glicemia/metabolismo , Fatores de Tempo , Síndrome Metabólica/mortalidade , Síndrome Metabólica/diagnóstico , Síndrome Metabólica/sangue , Síndrome Metabólica/epidemiologia , HDL-Colesterol/sangue , Insulina/sangue , Fatores de Risco de Doenças Cardíacas , Fatores de Risco
16.
Biotechnol Bioeng ; 121(5): 1674-1687, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38372655

RESUMO

Hollow fiber filter fouling is a common issue plaguing perfusion production process for biologics therapeutics, but the nature of filter foulant has been elusive. Here we studied cell culture materials especially Chinese hamster ovary (CHO) cell-derived extracellular vesicles in perfusion process to determine their role in filter fouling. We found that the decrease of CHO-derived small extracellular vesicles (sEVs) with 50-200 nm in diameter in perfusion permeates always preceded the increase in transmembrane pressure (TMP) and subsequent decrease in product sieving, suggesting that sEVs might have been retained inside filters and contributed to filter fouling. Using scanning electron microscopy and helium ion microscopy, we found sEV-like structures in pores and on foulant patches of hollow fiber tangential flow filtration filter (HF-TFF) membranes. We also observed that the Day 28 TMP of perfusion culture correlated positively with the percentage of foulant patch areas. In addition, energy dispersive X-ray spectroscopy-based elemental mapping microscopy and spectroscopy analysis suggests that foulant patches had enriched cellular materials but not antifoam. Fluorescent staining results further indicate that these cellular materials could be DNA, proteins, and even adherent CHO cells. Lastly, in a small-scale HF-TFF model, addition of CHO-specific sEVs in CHO culture simulated filter fouling behaviors in a concentration-dependent manner. Based on these results, we proposed a mechanism of HF-TFF fouling, in which filter pore constriction by CHO sEVs is followed by cake formation of cellular materials on filter membrane.


Assuntos
Anticorpos Monoclonais , Filtração , Cricetinae , Animais , Cricetulus , Células CHO , Perfusão , Filtração/métodos , Reatores Biológicos , Membranas Artificiais
17.
J Endovasc Ther ; : 15266028241241494, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561992

RESUMO

OBJECTIVE: To identify risk factors for in-stent restenosis (ISR) in patients undergoing stent placement for superior mesenteric artery dissection (SMAD) and to determine the hemodynamic mechanism underlying ISR. METHODS: For this retrospective study, patients with SMAD who had ISR after stent placement were included in the ISR group, and age- and sex-matched patients with SMAD who did not experience ISR after stent placement were included in the control group. Clinical, imaging, and hemodynamic data were assessed. Multivariable regression was used to identify independent ISR risk factors. Structural and fluid dynamics simulations were applied to determine the hemodynamic mechanism underlying the occurrence of ISR. RESULTS: The study population included 26 patients with ISR and 26 control patients. Multivariate analysis demonstrated that stent-to-vascular (S/V) ratio (odds ratio [OR], 1.14; 95% confidence interval [CI]: 1.00-1.29; p=0.045), stent proximal position >10 mm away from the SMA root (OR, 108.67; 95% CI: 3.09-3816.42; p=0.010), and high oscillatory shear index (OSI) area (OR, 1.25; 95% CI: 1.02-1.52; p=0.029) were predictors of ISR. In structural and fluid dynamics simulations, a stent proximal position near the abdominal aorta (AA) or entering into the AA reduced the contact area between the proximal struts of the stent and the vascular wall, and alleviated the distal lumen overdilation. CONCLUSION: The S/V ratio, stent proximal position away from the SMA root (>10 mm), and high OSI area are independent risk factors for ISR in patients with SMAD undergoing stent placement. Deploying the proximal end of the stent near the AA or entering into the AA appears to improve the hemodynamic environment in the SMA lumen and ultimately reduce the risk of ISR. CLINICAL IMPACT: In-stent restenosis is an uncommon but potentially catastrophic complication after stent placement for the management of superior mesenteric artery dissection. This study identified risk factors for in-stent restenosis and demonstrated that, as long as the stent can fully cover the dissection range, deploying the proximal end of the stent near the abdominal aorta or less entering into the abdominal aorta may reduce the risk of in-stent restenosis in this patient population.

18.
Pharm Res ; 41(3): 547-556, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38326531

RESUMO

OBJECTIVE: This study aimed to investigate the movement of liquid in the needle region of staked-in-needle pre-filled syringes using neutron imaging and synchrotron X-ray tomography. The objective was to gain insights into the dynamics of liquid presence and understand the factors contributing to needle clogging. METHODS: Staked-in-needle pre-filled syringes were examined using neutron radiography and synchrotron X-ray phase-contrast computed tomography. Neutron radiography provided a 2D visualization of liquid presence in the needle, while synchrotron X-ray tomography offered high-resolution 3D imaging to study detailed morphological features of the liquid. RESULTS: Neutron radiography revealed liquid presence in the needle region for as-received samples and after temperature and pressure cycling. Pressure cycling had a more pronounced effect on liquid formation. Synchrotron X-ray tomography confirmed the presence of liquid and revealed various morphologies, including droplets of different sizes, liquid segments blocking sections of the needle, and a thin layer covering the needle wall. Liquid presence was also observed between the steel needle and the glass barrel. CONCLUSIONS: The combination of neutron imaging and synchrotron X-ray tomography provided valuable insights into the dynamics of liquid movement in staked-in-needle pre-filled syringes. Temperature and pressure cycling were found to contribute to additional liquid formation, with pressure changes playing a significant role. The detailed morphological analysis enhanced the understanding of microstructural arrangements within the needle. This research contributes to addressing the issue of needle clogging and can guide the development of strategies to improve pre-filled syringe performance.


Assuntos
Agulhas , Tomografia Computadorizada por Raios X , Pressão , Temperatura , Vidro/química
19.
Vasc Med ; 29(3): 274-285, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38334057

RESUMO

BACKGROUND: False lumen changes (FLCs) are the main reference for the prognosis judgment and treatment plan selection for type IIa superior mesenteric artery dissection (SMAD). METHODS: For this retrospective study, 55 patients with symptomatic type IIa SMAD were included. Computational fluid dynamics (CFD) analysis was used to explore the hemodynamic basis of FLCs. Correlation and multiple linear regression analyses were performed to identify clinical, morphological and hemodynamic factors associated with FLCs. RESULTS: The FLCs of patients with successful conservative treatment (n = 29) are significantly higher than those with failed conservative treatment (n = 26) (58.5 ± 21.1% vs 10.9 ± 17.4%, p < 0.0001). Positive correlations were seen between FLCs and the morphological parameters false lumen length (FLL)/dissection entrance length (DEL) and FLL. In terms of hemodynamic parameters, negative correlations were seen between FLCs and time-averaged wall shear stress (TAWSS), vorticity, and high areas of TAWSS and vorticity, whereas positive correlations were seen between FLCs and oscillatory shear index (OSI), relative residence time (RRT), and high areas of OSI and RRT. Multiple linear regression analysis identified symptom duration (odds ratio [OR], 0.93; 95% CI, 0.91-0.96; p < 0.0001), FLL/DEL (OR, 1.30; 95% CI, 1.01-1.67; p = 0.044), and high RRT area (OR, 2.03; 95% CI, 1.48-2.78; p < 0.0001) as predictors of FLCs. CONCLUSION: The clinical predictor symptom duration, morphological factor FLL/DEL, and the hemodynamic factor high RRT area can serve as predictors of FLCs in patients with symptomatic type IIa SMAD.


Assuntos
Dissecção Aórtica , Hemodinâmica , Artéria Mesentérica Superior , Humanos , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Artéria Mesentérica Superior/diagnóstico por imagem , Artéria Mesentérica Superior/fisiopatologia , Dissecção Aórtica/fisiopatologia , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/terapia , Adulto , Fatores de Risco , Resultado do Tratamento , Idoso , Tratamento Conservador , Modelos Cardiovasculares , Angiografia por Tomografia Computadorizada , Modelagem Computacional Específica para o Paciente , Valor Preditivo dos Testes , Circulação Esplâncnica
20.
BMC Infect Dis ; 24(1): 738, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39061029

RESUMO

BACKGROUND: The objective of this study was to explore the correlation between statin administration in the intensive care unit (ICU) setting and the in-hospital mortality risk of patients suffering from sepsis-induced coagulopathy (SIC). METHODS: Utilizing a retrospective cohort study design, this investigation collected data from the Medical Information Mart for Intensive Care (MIMIC)-IV spanning 2008 to 2019. The diagnosis of SIC was established based on a SIC score of 4 or above. Statin usage during the ICU period was extracted from the prescription records based on the keywords of statin medications. The primary endpoint analyzed was the in-hospital mortality within the ICU, characterized by any death occurring during the ICU admission. RESULTS: During the follow-up, which had a median duration of approximately 7.28 days, 18.19% of the 4,777 SIC patients died in the ICU. Statin was linked with a decrease in the risk of in-hospital mortality for SIC patients in the ICU [hazard ratio (HR): 0.73, 95% confidence interval (CI): 0.60-0.89, P = 0.002]. Relative to rosuvastatin, the use of atorvastatin (HR: 0.54, 95% CI: 0.34-0.85, P = 0.008) or simvastatin (HR: 0.55, 95% CI: 0.33-0.92, P = 0.024), as well as combinations of multiple statins (HR: 0.36, 95% CI: 0.15-0.86, P = 0.022), was associated with a reduction in ICU in-hospital mortality risk. Subgroup analysis also suggested that the use of atorvastatin, simvastatin, or a combination of statins had an advantage over rosuvastatin in reducing ICU in-hospital mortality in SIC patients older than 65 years of age or SIC patients with respiratory failure or cardiogenic shock (all P < 0.05). CONCLUSION: The present study supports the potential benefits of statin use in mortality in SIC patients during ICU stays. The study encourages clinicians to consider the benefits of statins and supports the ongoing exploration of statins for enhanced outcomes in critical care settings.


Assuntos
Mortalidade Hospitalar , Inibidores de Hidroximetilglutaril-CoA Redutases , Unidades de Terapia Intensiva , Sepse , Humanos , Masculino , Sepse/mortalidade , Sepse/tratamento farmacológico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Feminino , Unidades de Terapia Intensiva/estatística & dados numéricos , Estudos Retrospectivos , Idoso , Pessoa de Meia-Idade , Transtornos da Coagulação Sanguínea/tratamento farmacológico , Transtornos da Coagulação Sanguínea/mortalidade , Transtornos da Coagulação Sanguínea/etiologia , Bases de Dados Factuais , Idoso de 80 Anos ou mais
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