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1.
J Fungi (Basel) ; 9(5)2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37233271

RESUMO

Coccidioides species are thermally dimorphic fungi found in geographically defined areas of the Western Hemisphere. The primary portal of entry is respiratory, with symptomatic pneumonic diseases as the most common presentation. Subsequent pulmonary complications as well as extrapulmonary metastatic infection may occur, either of which may be the presenting disease manifestation. Cavitary lung disease may be found incidentally or when investigating symptoms such as cough or hemoptysis. This study aims to explore the spectrum of coccidioidal cavities and the evaluation and management in a cohort of patients seen at Kern Medical over the last 12 years.

2.
JAMA Cardiol ; 8(4): 405, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36811870

RESUMO

This case report describes a 63-year-old male patient with a native bypass of the left coronary artery found incidentally while undergoing computed tomography angiography of the coronary arteries for clinical research purposes.


Assuntos
Doença da Artéria Coronariana , Humanos , Masculino , Doença da Artéria Coronariana/cirurgia , Ponte de Artéria Coronária
3.
J Investig Med High Impact Case Rep ; 10: 23247096221084852, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35354329

RESUMO

Coccidioidomycosis (CM) is a fungal disease that results from inhalation of spores of Coccidioides immitis and C posadasii. If symptomatic, disease primarily manifests as community-acquired pneumonia; however, additional pulmonary manifestations such as pleural effusion, empyema, and cavitation may occur. Diabetic patients have an increased risk of severe and cavitary CM. Cavitary disease may erode vasculature and pulmonary parenchyma leading to further complications. Furthermore, chronic cavities can become colonized as well and develop superimposed infections. This is a case of cavitary CM in uncontrolled diabetic nonadherent to treatment presenting with hemoptysis and mycetoma.


Assuntos
Coccidioidomicose , Pneumopatias Fúngicas , Coccidioides , Coccidioidomicose/complicações , Coccidioidomicose/diagnóstico , Coccidioidomicose/microbiologia , Hemoptise/etiologia , Humanos , Pulmão , Pneumopatias Fúngicas/diagnóstico , Pneumopatias Fúngicas/diagnóstico por imagem
4.
J Investig Med High Impact Case Rep ; 10: 23247096221077832, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35240889

RESUMO

In systemic lupus erythematosus (SLE), cardiac manifestations are known to be present in up to 50% of patients. However, it is rare for acute pericarditis to be the leading symptom at the time of diagnosis of SLE occurring in up to 1% of patients. We present a case series in which 3 patients with no prior history of SLE presented with acute pericarditis. This was found to be the leading manifestation of their disease, which ultimately led to the diagnosis of SLE. These patients were initially treated with nonsteroidal anti-inflammatory drugs and colchicines; however, steroids and disease-modifying anti-rheumatologic agents were ultimately added to their medical therapy.


Assuntos
Lúpus Eritematoso Sistêmico , Pericardite , Humanos , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/diagnóstico , Pericardite/diagnóstico , Pericardite/etiologia
5.
Open Forum Infect Dis ; 9(3): ofac017, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35169589

RESUMO

Coccidioidomycosis is the second most common endemic fungal infection in the United States. Prior descriptions of coccidioidal peritonitis include only single cases. We describe 17 new cases previously unreported from healthcare institutions in California. The majority of cases presented with nonspecific abdominal complaints. PubMed and Google Scholar were searched for additional case series and only single case reports and reviews of single cases were found. The diagnosis was confirmed by culture or histopathology and/or serology in each patient. All patients were treated with anti-fungal therapy. This case series demonstrates that coccidioidal peritonitis may be asymptomatic or present with only subtle abdominal symptoms. In a minority of our patients, the diagnosis was established incidentally during surgery. Based on this series, the overall outcome of coccidioidal peritonitis is favorable with long-term triazole treatment. The term cure is not usually used in disseminated coccidioidal disease because of the risk of late relapse.

6.
Cureus ; 13(7): e16170, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34268059

RESUMO

Background Methamphetamine use is associated with cardiovascular disease and significant morbidity and mortality. There is only one previous study performed on echocardiographic parameters in patients with methamphetamine cardiomyopathy. Methods We performed a retrospective review of medical records in a county hospital in Southern California with a high population of methamphetamine users. We reviewed medical records and echocardiogram findings in patients seen in our institution from November 2019 to November 2020 who had cardiomyopathy with and without methamphetamine use. We excluded patients who either left the hospital or expired before appropriate assessment. We divided our patient population into a case group (methamphetamine users) and a control group (non-methamphetamine users) to study and compare their echocardiographic parameters. Results Case group included a total of 254 patients and control group included 268 patients. Majority of the patient population were males - 178 (70%) and 180 (67%) in the case and control group respectively. Age was found to be statistically significant with the younger population in the case group (p = 0.0000). Our analysis revealed statistically significant difference in methamphetamine users compared to non-users in regards to left ventricle ejection fraction (33.65% ± 18.02 vs. 41.55% ± 15.61, p=0.0000), left ventricle mass index (122.49 grams/m2 ± 40.66 vs. 108.62 grams/m2 ± 32.82, p=0.0000), left ventricle end diastolic volume index (85.91 mL/m2 ± 37.40 vs. 72.44 mL/m2 ± 25.44; p=0.0000) and marginally significant right ventricle systolic pressure (42.29mmHg ± 17.53 vs. 39.59mmHg ± 15.61; p=0.0540) Conclusion Our results indicated that methamphetamine users had echocardiogram findings with decreased ejection fraction and increased left ventricular mass index, end-diastolic volume index, and right ventricular systolic pressure consistent with worse dilated cardiomyopathy comparison to non-users.

7.
J Investig Med High Impact Case Rep ; 9: 23247096211035238, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34293944

RESUMO

Drugs account for 2% of all the causes of acute pancreatitis. To date, there are approximately 26 reported cases of acute pancreatitis associated with the use of cannabis. We report the case of a 20-year-old male who presented with intractable nausea, vomiting, and epigastric pain and a lipase level of 1541 with reportedly no alcohol use, and no evidence of medication, biliary, or autoimmune etiology. However, the patient did endorse heavily smoking cannabis prior to symptom onset. He was instructed to abstain from cannabis use on discharge and has not presented to the hospital since this episode. The reporting of this case aims to increase awareness of cannabis as a differential diagnosis in cases of pancreatitis that is not due to typical etiologies such as gallstones, medications, and alcohol use. There has yet to be definitive evidence as to how cannabis can cause pancreatitis. Further studies must be conducted to better understand the association between cannabis use and acute pancreatitis and the mechanism by which cannabis affects the pancreas.


Assuntos
Cannabis , Pancreatite , Dor Abdominal , Doença Aguda , Adulto , Cannabis/efeitos adversos , Diagnóstico Diferencial , Humanos , Pancreatite/induzido quimicamente , Adulto Jovem
8.
Chem Sci ; 13(1): 210-217, 2021 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-35059169

RESUMO

We demonstrate phage-display screening on self-assembled ligands that enables the identification of oligopeptides that selectively bind dynamic supramolecular targets over their unassembled counterparts. The concept is demonstrated through panning of a phage-display oligopeptide library against supramolecular tyrosine-phosphate ligands using 9-fluorenylmethoxycarbonyl-phenylalanine-tyrosine-phosphate (Fmoc-FpY) micellar aggregates as targets. The 14 selected peptides showed no sequence consensus but were enriched in cationic and proline residues. The lead peptide, KVYFSIPWRVPM-NH2 (P7) was found to bind to the Fmoc-FpY ligand exclusively in its self-assembled state with K D = 74 ± 3 µM. Circular dichroism, NMR and molecular dynamics simulations revealed that the peptide interacts with Fmoc-FpY through the KVYF terminus and this binding event disrupts the assembled structure. In absence of the target micellar aggregate, P7 was further found to dynamically alternate between multiple conformations, with a preferred hairpin-like conformation that was shown to contribute to supramolecular ligand binding. Three identified phages presented appreciable binding, and two showed to catalyze the hydrolysis of a model para-nitro phenol phosphate substrate, with P7 demonstrating conformation-dependent activity with a modest k cat/K M = 4 ± 0.3 × 10-4 M-1 s-1.

9.
J Investig Med High Impact Case Rep ; 8: 2324709620966855, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33054423

RESUMO

Vasculitis is an inflammatory process involving blood vessels of various sizes, including the small vessels in the kidneys to the large vessels, such as the aorta. This inflammatory condition is usually autoimmune in nature and is associated with involvement of many locations, such as the sinuses, lungs, kidneys, and even the heart. Specifically, eosinophilic granulomatosis with polyangiitis (EGPA) is a systemic vasculitis that may initially hide as asthma, allergic rhinitis, and/or sinusitis. However, it is known to become a lethal disease once progressed to include cardiovascular manifestations. It is important to remember EGPA as a differential for any patient with a history of asthma, allergic rhinitis, and/or sinusitis who also presents with cardiovascular complaints and eosinophilia. Treatment recommendations focus on immunosuppression in such cases. In this article, we discuss the case of a 62-year-old male, with a known history of asthma, who presented to the emergency department with concern for his chest pain and right-sided weakness. He was later diagnosed with EGPA with eosinophilic myocarditis. Diagnosis and treatment are described.


Assuntos
Síndrome de Churg-Strauss/complicações , Miocardite/complicações , Síndrome de Churg-Strauss/tratamento farmacológico , Diagnóstico Diferencial , Humanos , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Miocardite/tratamento farmacológico , População Branca
10.
J Investig Med High Impact Case Rep ; 8: 2324709620959880, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32935587

RESUMO

Cryptococcus gattii is a species that has received more recognition in the recent past as distinct from Cryptococcus neoformans. C gattii is known to cause meningeal disease in both immunocompetent and immunosuppressed hosts. Patients may be clinically asymptomatic until immunosuppressive conditions occur such as corticosteroid treatment or an HIV infection. HIV-associated cryptococcal infections are most often due to C neoformans. C gattii is found in a minority. Speciation and subtyping of Cryptococcus are not always accomplished. In many parts of the world, there is no availability for speciation of Cryptococcus. Travel history may provide a clue to the most probable species. This case demonstrates a case of C gattii meningitis with a multiplicity of complications. These include advanced HIV disease secondary to nonadherence, immune reconstitution inflammatory syndrome, and superior sagittal sinus thrombosis. The patient represented diagnostic and therapeutic dilemmas over time. Headache was the primary symptom in cryptococcal meningitis, immune reconstitution inflammatory syndrome, and superior sagittal sinus thrombosis. All are discussed in detail as potential etiologies for the primary disease. Isavuconazonium is a relatively new broad-spectrum antifungal azole that was used as salvage therapy.


Assuntos
Antifúngicos/uso terapêutico , Cryptococcus gattii/isolamento & purificação , Infecções por HIV/complicações , Meningite Criptocócica/microbiologia , Líquido Cefalorraquidiano/microbiologia , Humanos , Síndrome Inflamatória da Reconstituição Imune/complicações , Masculino , Meningite Criptocócica/tratamento farmacológico , Pessoa de Meia-Idade , Nitrilas/uso terapêutico , Piridinas/uso terapêutico , Seio Sagital Superior/patologia , Trombose/complicações , Triazóis/uso terapêutico
11.
J Investig Med High Impact Case Rep ; 8: 2324709620938947, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32618206

RESUMO

We describe the case of a 41-year-old Hispanic male, inconsistently adherent to visits and workup due to socioeconomic challenges, who presented with a right testicular mass. Because of the overriding concern that this was malignant, he underwent a right orchiectomy. Pathology revealed granulomatous disease with no evidence of malignancy. No specific diagnosis was made histologically or microbiologically on primary laboratory investigation. Six months later, he developed swelling of the left testicle and was subsequently seen in consultation at the Infectious Disease Clinic Kern Medical. An extensive evaluation for granulomatous inflammation was undertaken without a positive result. A clinical diagnosis of tuberculous epididymal orchitis was made and the patient was initiated on standard 4-drug antituberculous therapy. There was a gradual resolution of pain and swelling. After 6 months of therapy, there was no evidence of residual disease. The patient remains asymptomatic after 8 months of post-therapy follow-up.


Assuntos
Orquite/etiologia , Neoplasias Testiculares/complicações , Neoplasias Testiculares/patologia , Tuberculose/complicações , Adulto , Antituberculosos/uso terapêutico , Diagnóstico Diferencial , Humanos , Masculino , Orquiectomia , Orquite/patologia , Tuberculose/tratamento farmacológico
12.
Nat Commun ; 11(1): 3463, 2020 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-32651374

RESUMO

Understanding the atomistic origin of defects in two-dimensional transition metal dichalcogenides, their impact on the electronic properties, and how to control them is critical for future electronics and optoelectronics. Here, we demonstrate the integration of thermochemical scanning probe lithography (tc-SPL) with a flow-through reactive gas cell to achieve nanoscale control of defects in monolayer MoS2. The tc-SPL produced defects can present either p- or n-type doping on demand, depending on the used gasses, allowing the realization of field effect transistors, and p-n junctions with precise sub-µm spatial control, and a rectification ratio of over 104. Doping and defects formation are elucidated by means of X-Ray photoelectron spectroscopy, scanning transmission electron microscopy, and density functional theory. We find that p-type doping in HCl/H2O atmosphere is related to the rearrangement of sulfur atoms, and the formation of protruding covalent S-S bonds on the surface. Alternatively, local heating MoS2 in N2 produces n-character.

13.
Chemistry ; 26(38): 8372-8376, 2020 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-32428282

RESUMO

Transient self-assembly of dipeptide nanofibers with lifetimes that are predictably variable through dipeptide sequence design are presented. This was achieved using 1,8-naphthalimide (NI) amino acid methyl-esters (Phe, Tyr, Leu) that are biocatalytically coupled to amino acid-amides (Phe, Tyr, Leu, Val, Ala, Ser) to form self-assembling NI-dipeptides. However, competing hydrolysis of the dipeptides results in disassembly. It was demonstrated that the kinetic parameters like lifetimes of these nanofibers can be predictably regulated by the thermodynamic parameter, namely the self-assembly propensity of the constituent dipeptide sequence. These lifetimes could vary from minutes, to hours, to permanent gels that do not degrade. Moreover, the in-built NI fluorophore was utilized to image the transient nanostructures in solution with stimulated emission depletion (STED) based super-resolution fluorescence microscopy.


Assuntos
Dipeptídeos/química , Nanofibras/química , Nanoestruturas/química , Naftalimidas/química , Aminoácidos , Géis , Hidrólise , Cinética
14.
Nat Chem ; 10(7): 696-703, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29713031

RESUMO

Aqueous compatible supramolecular materials hold promise for applications in environmental remediation, energy harvesting and biomedicine. One remaining challenge is to actively select a target structure from a multitude of possible options, in response to chemical signals, while maintaining constant, physiological conditions. Here, we demonstrate the use of amino acids to actively decorate a self-assembling core molecule in situ, thereby controlling its amphiphilicity and consequent mode of assembly. The core molecule is the organic semiconductor naphthalene diimide, functionalized with D- and L- tyrosine methyl esters as competing reactive sites. In the presence of α-chymotrypsin and a selected encoding amino acid, kinetic competition between ester hydrolysis and amidation results in covalent or non-covalent amino acid incorporation, and variable supramolecular self-assembly pathways. Taking advantage of the semiconducting nature of the naphthalene diimide core, electronic wires could be formed and subsequently degraded, giving rise to temporally regulated electro-conductivity.


Assuntos
Aminoácidos/química , Biocatálise , Nanoestruturas , Cromatografia Líquida de Alta Pressão , Quimotripsina/química , Hidrólise , Cinética , Microscopia Eletrônica de Transmissão , Estereoisomerismo , Tirosina/química
15.
Angew Chem Int Ed Engl ; 56(46): 14511-14515, 2017 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-28941038

RESUMO

The reversible regulation of catalytic activity is a feature found in natural enzymes which is not commonly observed in artificial catalytic systems. Here, we fabricate an artificial hydrolase with pH-switchable activity, achieved by introducing a catalytic histidine residue at the terminus of a pH-responsive peptide. The peptide exhibits a conformational transition from random coil to ß-sheet by changing the pH from acidic to alkaline. The ß-sheet self-assembles to form long fibrils with the hydrophobic edge and histidine residues extending in an ordered array as the catalytic microenvironment, which shows significant esterase activity. Catalytic activity can be reversible switched by pH-induced assembly/disassembly of the fibrils into random coils. At higher concentrations, the peptide forms a hydrogel which is also catalytically active and maintains its reversible (de-)activation.


Assuntos
Domínio Catalítico , Hidrolases/metabolismo , Peptídeos/metabolismo , Sítios de Ligação , Dicroísmo Circular , Histidina/metabolismo , Hidrogéis , Concentração de Íons de Hidrogênio , Hidrolases/química , Interações Hidrofóbicas e Hidrofílicas , Peptídeos/química , Conformação Proteica , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
16.
Carbon N Y ; 111: 380-384, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28690336

RESUMO

Structural properties of sixteen (16) commercial samples of graphene-based materials (GBM) labelled as graphene, graphene oxide or reduced graphene oxide are investigated at room temperature using X-ray diffraction (XRD) and Raman spectroscopy. Based on the observed correlation between the results obtained with these two techniques, these samples are classified into three groups: Group A of seven samples consisting of graphitic nanosheets with evaluated thickness ≃20 nm and exhibiting both the 2H and 3R phases in XRD; Group B of six samples exhibiting XRD spectra characteristic of either graphene oxides (GO) or carbons with some order; and Group C of three samples with XRD spectra characteristic of disordered carbons. The relative intensities and widths of D, G, D', 2D and (D + D') bands in the Raman spectra are equally distinguishable between the samples in groups A, B and C. The width of the D-band is the smallest for Group A samples, intermediate for group B and the largest for group C samples. The intensity ratio I(D)/I(G) of the D and G bands in the Raman spectra of the samples is used to quantify the Raman-active defects whose concentration increases in going from samples in Group A to those in Group C.

17.
Nat Nanotechnol ; 11(11): 960-967, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27694850

RESUMO

Sequence-specific polymers, such as oligonucleotides and peptides, can be used as building blocks for functional supramolecular nanomaterials. The design and selection of suitable self-assembling sequences is, however, challenging because of the vast combinatorial space available. Here we report a methodology that allows the peptide sequence space to be searched for self-assembling structures. In this approach, unprotected homo- and heterodipeptides (including aromatic, aliphatic, polar and charged amino acids) are subjected to continuous enzymatic condensation, hydrolysis and sequence exchange to create a dynamic combinatorial peptide library. The free-energy change associated with the assembly process itself gives rise to selective amplification of self-assembling candidates. By changing the environmental conditions during the selection process, different sequences and consequent nanoscale morphologies are selected.


Assuntos
Nanoestruturas/química , Biblioteca de Peptídeos , Aminoácidos/química , Cromatografia Líquida de Alta Pressão , Dicroísmo Circular , Dipeptídeos/química , Espectrometria de Massas , Espectroscopia de Infravermelho com Transformada de Fourier
18.
Am J Physiol Cell Physiol ; 295(2): C440-50, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18524938

RESUMO

Brain edema is an important factor leading to morbidity and mortality associated with primary brain tumors. Dexamethasone, a synthetic glucocorticoid, is routinely prescribed with antineoplastic agents to alleviate pain associated with chemotherapy and reduce intracranial pressure. We investigated whether dexamethasone treatment increased the expression and activity of multidrug resistance (MDR) transporters at the blood-brain barrier. Treatment of primary rat brain microvascular endothelial cells with submicromolar concentrations of dexamethasone induced significantly higher levels of drug efflux transporters such as breast cancer resistance protein (abcg2), P-glycoprotein (P-gp; abcb1a/abcb1b), and MDR protein 2 (Mrp2; abcc2) as indicted by protein and mRNA levels as well as by functional activity. The effect of dexamethasone on transporter function was significant within 6 h of treatment, was dose dependent, and was reversible. Dexamethasone-induced upregulation of Bcrp and P-gp expression and function was partially abrogated by the glucocorticoid receptor (GR) antagonist RU486. In contrast, RU486 had no effect on the dexamethasone-induced upregulation of Mrp2, suggesting a GR-independent regulation of Mrp2, and a GR-dependent regulation of P-gp and Bcrp. In addition to the dexamethasone-induced upregulation of MDR transporters, we measured a dose-dependent and reversible increase in the expression of the nuclear transcription factor pregnane xenobiotic receptor (PXR). Administering dexamethasone to rats caused increased expression of PXR in brain microvessels within 24 h. These results suggest that adjuvant therapy with corticosteroids such as dexamethasone in the treatment of brain tumors may increase the expression of MDR transporters at the blood-brain barrier through pathways involving GR and PXR.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Barreira Hematoencefálica/metabolismo , Dexametasona/farmacologia , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Barreira Hematoencefálica/citologia , Barreira Hematoencefálica/efeitos dos fármacos , Western Blotting , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Células Cultivadas , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Expressão Gênica/efeitos dos fármacos , Glucocorticoides/farmacologia , Indenos/farmacologia , Masculino , Mifepristona/farmacologia , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Receptor de Pregnano X , Carbonitrila de Pregnenolona/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores de Glucocorticoides/antagonistas & inibidores , Receptores de Glucocorticoides/metabolismo , Receptores de Esteroides/genética , Receptores de Esteroides/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Regulação para Cima/efeitos dos fármacos
19.
J Biol Chem ; 282(42): 30341-5, 2007 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-17537734

RESUMO

Janus kinase 3 (Jak3) is a non-receptor tyrosine kinase known to be expressed in hematopoietic cells. Studies of whole organ homogenates show that Jak3 is also expressed in the intestines of both human and mice. However, neither its expression nor its function has been defined in intestinal epithelial enterocytes. The present studies demonstrate that functional Jak3 is expressed in human intestinal enterocytes HT-29 Cl-19A and Caco-2 and plays an essential role in the intestinal epithelial wound repair process in response to interleukin 2 (IL-2). Exogenous IL-2 enhanced the wound repair of intestinal enterocytes in a dose-dependent manner. Activation by IL-2 led to rapid tyrosine phosphorylation and redistribution of Jak3. IL-2-stimulated redistribution of Jak3 was inhibited by the Jak3-specific inhibitor WHI-P131. IL-2 also induced Jak3-dependent redistribution of the actin cytoskeleton in migrating cells. In these cells Jak3 interacted with the intestinal and renal epithelial cell-specific cytoskeletal protein villin in an IL-2-dependent manner. Inhibition of Jak3 activation resulted in loss of tyrosine phosphorylation of villin and a significant decrease in wound repair of the intestinal epithelial cells. Previously, we had shown that tyrosine phosphorylation of villin is important for cytoskeletal remodeling and cell migration. The present study demonstrates a novel pathway in intestinal enterocytes in which IL-2 enhances intestinal wound repair through mechanisms involving Jak3 and its interactions with villin.


Assuntos
Enterócitos/enzimologia , Interleucina-2/farmacologia , Mucosa Intestinal/lesões , Janus Quinase 3/metabolismo , Proteínas dos Microfilamentos/metabolismo , Cicatrização/efeitos dos fármacos , Actinas/metabolismo , Animais , Células CACO-2 , Movimento Celular/efeitos dos fármacos , Citoesqueleto/metabolismo , Relação Dose-Resposta a Droga , Enterócitos/patologia , Ativação Enzimática/efeitos dos fármacos , Células-Tronco Hematopoéticas/enzimologia , Humanos , Mucosa Intestinal/enzimologia , Mucosa Intestinal/patologia , Camundongos , Fosforilação/efeitos dos fármacos , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Transporte Proteico/efeitos dos fármacos , Quinazolinas/farmacologia , Tirosina/metabolismo
20.
Chemotherapy ; 53(3): 210-7, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17356269

RESUMO

BACKGROUND: We previously showed that the anti-inflammatory drug, sulfasalazine (salicylazosulfapyridine, SASP), can arrest proliferation of MCF-7 and MDA-MB-231 mammary cancer cells by inhibiting uptake of cystine via the x(c-) cystine/glutamate antiporter. Here we examined SASP with regard to reduction of cellular glutathione (GSH) levels and drug efficacy-enhancing ability. METHODS: GSH levels were measured spectrophotometrically. Cellular drug retention was determined with 3H-labeled methotrexate, and drug efficacy with a colony formation assay. RESULTS: Incubation of the mammary cancer cells with SASP (0.3-0.5 mM) led to reduction of their GSH content in a time- and concentration-dependent manner. Similar to MK-571, a multidrug resistance-associated protein inhibitor, SASP increased intracellular accumulation of methotrexate. Preincubation of cells with SASP (0.3 mM) significantly enhanced the potency of the anticancer agent doxorubicin (2.5 nM). CONCLUSIONS: SASP-induced reduction of cellular GSH levels can lead to growth arrest of mammary cancer cells and enhancement of anticancer drug efficacy.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Antibióticos Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Doxorrubicina/farmacologia , Sulfassalazina/farmacologia , Subfamília B de Transportador de Cassetes de Ligação de ATP/antagonistas & inibidores , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Antimetabólitos Antineoplásicos/metabolismo , Carcinoma/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Sinergismo Farmacológico , Glutationa/análise , Glutationa/metabolismo , Humanos , Metotrexato/metabolismo , Oxirredução , Propionatos/farmacologia , Quinolinas/farmacologia , Ensaio Tumoral de Célula-Tronco , Membro 4 da Subfamília B de Transportadores de Cassetes de Ligação de ATP
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