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1.
Neurol India ; 72(4): 791-796, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-39216035

RESUMEN

BACKGROUND AND PURPOSE: Cerebral venous and sinus thrombosis (CVST) leads to perfusion abnormality in the brain. Our aim was to assess perfusion abnormalities in the center and periphery of the parenchymal lesion in CVST patients and correlate with the clinical outcome. MATERIALS AND METHODS: Dynamic susceptibility contrast (DSC) perfusion imaging was performed in patients with CVST. Relative cerebral blood flow (rCBF), relative cerebral blood volume (rCBV), and mean transit time (MTT) values were obtained in the center and periphery of the parenchymal lesion. RESULTS: A total of 30 consecutive patients of CVST were included in the study. Parenchymal lesion was present in 21 (70%) patients. In rest 9, perfusion map was showing some abnormality although conventional MRI was normal. Mean rCBV and MTT were increasing from periphery of the lesion to the center (rCBV 69.93 ± 29.79 at periphery (PL2) to 92.49 ± 32.07 at center of the lesion and 69.19 ± 25.52 at normal appearing contralateral brain parenchyma (NABP). MTT 11.83 ± 3.76 at periphery (PL2) to 15.27 ± 5.49 at center of the lesion and 10.63 ± 3.37 at NABP). rCBV and MTT from abnormal perfusion areas from 9 patients without parenchymal abnormalities are 92.89 ± 17.76 and 15.92 ± 3.66 respectively. CONCLUSION: There is an increasing trend of MTT and rCBV from periphery to center of the parenchymal lesion. MTT is the most consistent parameter to be abnormal in patients of CVST even in patients without parenchymal lesion. Residual neurological deficit was found in patients with increased rCBV and having large hemorrhagic infarct.


Asunto(s)
Circulación Cerebrovascular , Trombosis de los Senos Intracraneales , Humanos , Trombosis de los Senos Intracraneales/diagnóstico por imagen , Femenino , Adulto , Masculino , Circulación Cerebrovascular/fisiología , Persona de Mediana Edad , Adulto Joven , Imagen por Resonancia Magnética/métodos , Adolescente , Angiografía por Resonancia Magnética , Encéfalo/diagnóstico por imagen , Encéfalo/irrigación sanguínea , Trombosis de la Vena/diagnóstico por imagen
3.
Am J Physiol Cell Physiol ; 327(3): C671-C683, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38912732

RESUMEN

Fibrostenosing Crohn's disease (CD) represents a challenging clinical condition characterized by the development of symptomatic strictures within the gastrointestinal tract. Despite therapeutic advancements in managing inflammation, the progression of fibrostenotic complications remains a significant concern, often necessitating surgical intervention. Recent investigations have unveiled the pivotal role of smooth muscle cell hyperplasia in driving luminal narrowing and clinical symptomatology. Drawing parallels to analogous inflammatory conditions affecting other organs, such as the airways and blood vessels, sheds light on common underlying mechanisms of muscular hyperplasia. This review synthesizes current evidence to elucidate the mechanisms underlying smooth muscle cell proliferation in CD-associated strictures, offering insights into potential therapeutic targets. By highlighting the emerging significance of muscle thickening as a novel therapeutic target, this review aims to inform future research endeavors and clinical strategies with the goal to mitigate the burden of fibrostenotic complications in CD and other conditions.


Asunto(s)
Enfermedad de Crohn , Hiperplasia , Músculo Liso , Enfermedad de Crohn/patología , Enfermedad de Crohn/complicaciones , Humanos , Hiperplasia/patología , Constricción Patológica , Animales , Músculo Liso/patología , Músculo Liso/metabolismo , Fibrosis , Proliferación Celular , Miocitos del Músculo Liso/patología , Miocitos del Músculo Liso/metabolismo
4.
Nat Commun ; 15(1): 4408, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38782886

RESUMEN

Phase separation and percolation contribute to phase transitions of multivalent macromolecules. Contributions of percolation are evident through the viscoelasticity of condensates and through the formation of heterogeneous distributions of nano- and mesoscale pre-percolation clusters in sub-saturated solutions. Here, we show that clusters formed in sub-saturated solutions of FET (FUS-EWSR1-TAF15) proteins are affected differently by glutamate versus chloride. These differences on the nanoscale, gleaned using a suite of methods deployed across a wide range of protein concentrations, are prevalent and can be unmasked even though the driving forces for phase separation remain unchanged in glutamate versus chloride. Strikingly, differences in anion-mediated interactions that drive clustering saturate on the micron-scale. Beyond this length scale the system separates into coexisting phases. Overall, we find that sequence-encoded interactions, mediated by solution components, make synergistic and distinct contributions to the formation of pre-percolation clusters in sub-saturated solutions, and to the driving forces for phase separation.


Asunto(s)
Transición de Fase , Ácido Glutámico/química , Cloruros/química , Humanos , Soluciones , Proteínas de Unión al ARN/metabolismo , Proteínas de Unión al ARN/química , Separación de Fases
5.
Cureus ; 16(2): e55043, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38550462

RESUMEN

Phantom bladder pain, a rare condition following cystectomy, can pose a challenge to pain management providers. We present the case of a 43-year-old male who developed severe phantom bladder pain post-cystectomy. Despite multiple treatments, his symptoms persisted, significantly affecting his quality of life. Dorsal root ganglion stimulation (DRGS) was attempted after conventional therapies failed. The DRGS trial provided significant relief, leading to permanent implantation and a 90% reduction in pain. This case highlights DRGS as a potential treatment for phantom bladder pain, expanding its applications beyond traditional uses. Further research is needed to elucidate its mechanisms and broader applicability.

6.
Pharmaceutics ; 16(2)2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38399262

RESUMEN

Developing successful nanomedicine hinges on regulating nanoparticle surface interactions within biological systems, particularly in intravenous nanotherapeutics. We harnessed the surface interactions of gold nanoparticles (AuNPs) with serum proteins, incorporating a γ-globulin (γG) hard surface corona and chemically conjugating Doxorubicin to create an innovative hybrid anticancer nanobioconjugate, Dox-γG-AuNPs. γG (with an isoelectric point of ~7.2) enhances cellular uptake and exhibits pH-sensitive behaviour, favouring targeted cancer cell drug delivery. In cell line studies, Dox-γG-AuNPs demonstrated a 10-fold higher cytotoxic potency compared to equivalent doxorubicin concentrations, with drug release favoured at pH 5.5 due to the γ-globulin corona's inherent pH sensitivity. This bioinspired approach presents a novel strategy for designing hybrid anticancer therapeutics. Our study also explored the intricacies of the p53-mediated ROS pathway's role in regulating cell fate, including apoptosis and necrosis, in response to these treatments. The pathway's delicate balance of ROS emerged as a critical determinant, warranting further investigation to elucidate its mechanisms and implications. Overall, leveraging the robust γ-globulin protein corona on AuNPs enhances biostability in harsh serum conditions, augments anticancer potential within pH-sensitive environments, and opens promising avenues for bioinspired drug delivery and the design of novel anticancer hybrids with precise targeting capabilities.

8.
Res Sq ; 2023 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-37790538

RESUMEN

Multivalent proteins undergo coupled segregative and associative phase transitions. Phase separation, a segregative transition, is driven by macromolecular solubility, and this leads to coexisting phases above system-specific saturation concentrations. Percolation is a continuous transition that is driven by multivalent associations among cohesive motifs. Contributions from percolation are highlighted by the formation of heterogeneous distributions of clusters in sub-saturated solutions, as was recently reported for Fused in sarcoma (FUS) and FET family proteins. Here, we show that clustering and phase separation are defined by a separation of length- and energy-scales. This is unmasked when glutamate is the primary solution anion. Glutamate is preferentially excluded from protein sites, and this enhances molecular associations. Differences between glutamate and chloride are manifest at ultra-low protein concentrations. These differences are amplified as concentrations increase, and they saturate as the micron-scale is approached. Therefore, condensate formation in supersaturated solutions and clustering in sub-saturated are governed by distinct energy and length scales. Glutamate, unlike chloride, is the dominant intracellular anion, and the separation of scales, which is masked in chloride, is unmasked in glutamate. Our work highlights how components of cellular milieus and sequence-encoded interactions contribute to amplifying distinct contributions from associative versus segregative phase transitions.

9.
Reg Anesth Pain Med ; 2023 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-37816519

RESUMEN

With headache being one of the most common chief complaints, it is essential for pain practitioners to interpret and differentiate a variety of headache characteristics to accurately diagnose and treat specific headache disorders. Certain misconceptions often lead to misdiagnosis. This article presents and discusses six myths about several common headache disorders (migraine, tension-type headache, cluster headache, cervicogenic headache, sinus headache, and occipital neuralgia) often encountered in clinical practice. The discussion is based primarily on the International Classification of Headache Disorders, 3rd edition and the latest studies. Recognizing and understanding the intricacies behind key headache diagnoses will help providers devise appropriate plans to better care for their patients.

10.
Cancer Res ; 83(24): 4142-4160, 2023 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-37801613

RESUMEN

Prostate cancer remains the second leading cause of cancer death in men in Western cultures. A deeper understanding of the mechanisms by which prostate cancer cells divide to support tumor growth could help devise strategies to overcome treatment resistance and improve survival. Here, we identified that the mitotic AGC family protein kinase citron kinase (CIT) is a pivotal regulator of prostate cancer growth that mediates prostate cancer cell interphase progression. Increased CIT expression correlated with prostate cancer growth induction and aggressive prostate cancer progression, and CIT was overexpressed in prostate cancer compared with benign prostate tissue. CIT overexpression was controlled by an E2F2-Skp2-p27 signaling axis and conferred resistance to androgen-targeted treatment strategies. The effects of CIT relied entirely on its kinase activity. Conversely, CIT silencing inhibited the growth of cell lines and xenografts representing different stages of prostate cancer progression and treatment resistance but did not affect benign epithelial prostate cells or nonprostatic normal cells, indicating a potential therapeutic window for CIT inhibition. CIT kinase activity was identified as druggable and was potently inhibited by the multikinase inhibitor OTS-167, which decreased the proliferation of treatment-resistant prostate cancer cells and patient-derived organoids. Isolation of the in vivo CIT substrates identified proteins involved in diverse cellular functions ranging from proliferation to alternative splicing events that are enriched in treatment-resistant prostate cancer. These findings provide insights into the regulation of aggressive prostate cancer cell behavior by CIT and identify CIT as a functionally diverse and druggable driver of prostate cancer progression. SIGNIFICANCE: The poorly characterized protein kinase citron kinase is a therapeutic target in prostate cancer that drives tumor growth by regulating diverse substrates, which control several hallmarks of aggressive prostate cancer progression. See related commentary by Mishra et al., p. 4008.


Asunto(s)
Próstata , Neoplasias de la Próstata , Proteínas Quinasas , Humanos , Masculino , Línea Celular Tumoral , Proliferación Celular , Próstata/patología , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/metabolismo , Proteínas Quinasas/metabolismo , Transducción de Señal
11.
Biophys J ; 2023 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-37717144

RESUMEN

Macromolecular solubility is an important contributor to the driving forces for phase separation. Formally, the driving forces in a binary mixture comprising a macromolecule dissolved in a solvent can be quantified in terms of the saturation concentration, which is the threshold macromolecular concentration above which the mixture separates into coexisting dense and dilute phases. In addition, the second virial coefficient, which measures the effective strength of solvent-mediated intermolecular interactions provides direct assessments of solvent quality. The sign and magnitude of second virial coefficients will be governed by a combination of solution conditions and the nature of the macromolecule of interest. Here, we show, using a combination of theory, simulation, and in vitro experiments, that titrations of crowders, providing they are true depletants, can be used to extract the intrinsic driving forces for macromolecular phase separation. This refers to saturation concentrations in the absence of crowders and the second virial coefficients that quantify the magnitude of the incompatibility between macromolecules and the solvent. Our results show how the depletion-mediated attractions afforded by crowders can be leveraged to obtain comparative assessments of macromolecule-specific, intrinsic driving forces for phase separation.

12.
bioRxiv ; 2023 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-37609232

RESUMEN

Multivalent proteins undergo coupled segregative and associative phase transitions. Phase separation, a segregative transition, is driven by macromolecular solubility, and this leads to coexisting phases above system-specific saturation concentrations. Percolation is a continuous transition that is driven by multivalent associations among cohesive motifs. Contributions from percolation are highlighted by the formation of heterogeneous distributions of clusters in sub-saturated solutions, as was recently reported for Fused in sarcoma (FUS) and FET family proteins. Here, we show that clustering and phase separation are defined by a separation of length- and energy-scales. This is unmasked when glutamate is the primary solution anion. Glutamate is preferentially excluded from protein sites, and this enhances molecular associations. Differences between glutamate and chloride are manifest at ultra-low protein concentrations. These differences are amplified as concentrations increase, and they saturate as the micron-scale is approached. Therefore, condensate formation in supersaturated solutions and clustering in sub-saturated are governed by distinct energy and length scales. Glutamate, unlike chloride, is the dominant intracellular anion, and the separation of scales, which is masked in chloride, is unmasked in glutamate. Our work highlights how components of cellular milieus and sequence-encoded interactions contribute to amplifying distinct contributions from associative versus segregative phase transitions.

13.
Microsyst Nanoeng ; 9: 107, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37649779

RESUMEN

Membranes are fundamental elements within organ-on-a-chip (OOC) platforms, as they provide adherent cells with support, allow nutrients (and other relevant molecules) to permeate/exchange through membrane pores, and enable the delivery of mechanical or chemical stimuli. Through OOC platforms, physiological processes can be studied in vitro, whereas OOC membranes broaden knowledge of how mechanical and chemical cues affect cells and organs. OOCs with membranes are in vitro microfluidic models that are used to replace animal testing for various applications, such as drug discovery and disease modeling. In this review, the relevance of OOCs with membranes is discussed as well as their scaffold and actuation roles, properties (physical and material), and fabrication methods in different organ models. The purpose was to aid readers with membrane selection for the development of OOCs with specific applications in the fields of mechanistic, pathological, and drug testing studies. Mechanical stimulation from liquid flow and cyclic strain, as well as their effects on the cell's increased physiological relevance (IPR), are described in the first section. The review also contains methods to fabricate synthetic and ECM (extracellular matrix) protein membranes, their characteristics (e.g., thickness and porosity, which can be adjusted depending on the application, as shown in the graphical abstract), and the biological materials used for their coatings. The discussion section joins and describes the roles of membranes for different research purposes and their advantages and challenges.

14.
bioRxiv ; 2023 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-37461587

RESUMEN

Macromolecular solubility is an important contributor to the driving forces for phase separation. Formally, the driving forces in a binary mixture comprising a macromolecule dissolved in a solvent can be quantified in terms of the saturation concentration, which is the threshold macromolecular concentration above which the mixture separates into coexisting dense and dilute phases. Additionally, the second virial coefficient, which measures the effective strength of solvent-mediated intermolecular interactions provides direct assessments of solvent quality. The sign and magnitude of second virial coefficients will be governed by a combination of solution conditions and the nature of the macromolecule of interest. Here, we show, using a combination of theory, simulation, and in vitro experiments, that titrations of crowders, providing they are true depletants, can be used to extract the intrinsic driving forces for macromolecular phase separation. This refers to saturation concentrations in the absence of crowders and the second virial coefficients that quantify the magnitude of the incompatibility between macromolecules and the solvent. Our results show how the depletion-mediated attractions afforded by crowders can be leveraged to obtain comparative assessments of macromolecule-specific, intrinsic driving forces for phase separation. SIGNIFICANCE: Phase separation has emerged as a process of significant relevance to sorting macromolecules into distinct compartments, thereby enabling spatial and temporal control over cellular matter. Considerable effort is being invested into uncovering the driving forces that enable the separation of macromolecular solutions into coexisting phases. At its heart, this process is governed by the balance of macromolecule-solvent, inter-macromolecule, and solvent-solvent interactions. We show that the driving forces for phase separation, including the coefficients that measure interaction strengths between macromolecules, can be extracted by titrating the concentrations of crowders that enable macromolecules to phase separate at lower concentrations. Our work paves the way to leverage specific categories of measurements for quantitative characterizations of driving forces for phase separation.

15.
Cancer Res Commun ; 3(6): 1078-1092, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37377604

RESUMEN

Triple-negative breast cancer (TNBC) has high relapse and metastasis rates and a high proportion of cancer stem-like cells (CSC), which possess self-renewal and tumor initiation capacity. MELK (maternal embryonic leucine zipper kinase), a protein kinase of the Snf1/AMPK kinase family, is known to promote CSC maintenance and malignant transformation. However, the role of MELK in TNBC metastasis is unknown; we sought to address this in the current study. We found that MELK mRNA levels were higher in TNBC tumors [8.11 (3.79-10.95)] than in HR+HER2- tumors [6.54 (2.90-9.26)]; P < 0.001]. In univariate analysis, patients with breast cancer with high-MELK-expressing tumors had worse overall survival (P < 0.001) and distant metastasis-free survival (P < 0.01) than patients with low-MELK-expressing tumors. In a multicovariate Cox regression model, high MELK expression was associated with shorter overall survival after adjusting for other baseline risk factors. MELK knockdown using siRNA or MELK inhibition using the MELK inhibitor MELK-In-17 significantly reduced invasiveness, reversed epithelial-to-mesenchymal transition, and reduced CSC self-renewal and maintenance in TNBC cells. Nude mice injected with CRISPR MELK-knockout MDA-MB-231 cells exhibited suppression of lung metastasis and improved overall survival compared with mice injected with control cells (P < 0.05). Furthermore, MELK-In-17 suppressed 4T1 tumor growth in syngeneic BALB/c mice (P < 0.001). Our findings indicate that MELK supports metastasis by promoting epithelial-to-mesenchymal transition and the CSC phenotype in TNBC. Significance: These findings indicate that MELK is a driver of aggressiveness and metastasis in TNBC.


Asunto(s)
Neoplasias de la Mama Triple Negativas , Humanos , Animales , Ratones , Neoplasias de la Mama Triple Negativas/genética , Ratones Desnudos , Leucina Zippers , Proliferación Celular/fisiología , Recurrencia Local de Neoplasia , Proteínas Serina-Treonina Quinasas/genética
16.
Cureus ; 15(3): e35759, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37025751

RESUMEN

The number of joint replacement surgeries, especially knee replacement surgeries, is rising with the rising geriatric population. Chronic unremitting knee pain post-total knee replacement surgery is a common phenomenon. Usually, the pain responds to conservative measures, including physical therapy and medical management. In some patients, the pain post-knee replacement surgery can be refractory and unremitting. In such scenarios, peripheral nerve stimulation, or neuromodulation, can be an effective option.

17.
Cureus ; 15(2): e34681, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36909041

RESUMEN

Dorsal root ganglion stimulation is a relatively new treatment option for chronic pain conditions such as pudendal neuralgia, which is a chronic pain condition affecting the pudendal nerve in the pelvic region. Pudendal neuralgia is a debilitating condition that can significantly affect the patient's quality of life. In dorsal root ganglion stimulation, a small device is implanted that delivers electrical impulses to the dorsal root ganglion to modulate pain signals coming from the pudendal nerve. The procedure is considered investigational and has been investigated in case series and case reports with promising results. However, more research is needed to fully understand its safety and effectiveness. This case report highlights the potential of dorsal root ganglion stimulation as a treatment option for pudendal neuralgia and the need for further research to establish it as a standard treatment option.

19.
Cureus ; 15(1): e33519, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36779160

RESUMEN

Abernethy malformation is an extrahepatic congenital portosystemic shunt characterized by the diversion of the portal blood away from the liver through a shunt that drains directly into the inferior vena cava. We present a case of a male child with Abernethy malformation, which was initially diagnosed as cyanotic heart disease due to pulmonary arteriovenous malformation. However, after proper clinical evaluation and investigations, the diagnosis of Abernethy malformation was established. Thereafter, the patient was successfully treated with endovascular embolization. At one year follow-up, marked relief in exertional dyspnea and improvement in physical growth was achieved with no observable complications.

20.
BMJ Case Rep ; 16(1)2023 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-36693701

RESUMEN

Mandibular arteriovenous malformations (AVMs) are rare lesions which can present with life-threatening haemorrhage. Endovascular embolisation can be life saving for these patients. We discuss a patient of mandibular AVM, who initially presented with reports of massive oral bleeding. The lesion was only partially embolised via transarterial route, as the nidus could not be penetrated completely. In view of rebleeding within 72 hours from the same site, a second embolisation procedure was done via combined, transarterial and transvenous approaches. Coils and onyx were used as embolising agents. Complete embolisation was achieved via combined approach. No further bleeding episodes were seen at 1-year follow-up. Endovascular embolisation of mandibular AVMs can be technically challenging and, hence, a sound knowledge of the anatomy as well as the possible modification of technique is essential to achieve complete obliteration of the lesion and to maximise the benefit of embolisation and to avoid major radical surgery.


Asunto(s)
Embolización Terapéutica , Malformaciones Arteriovenosas Intracraneales , Humanos , Malformaciones Arteriovenosas Intracraneales/terapia , Embolización Terapéutica/métodos , Mandíbula/patología , Hemorragia Bucal , Resultado del Tratamiento
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