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1.
Nucleic Acids Res ; 50(18): 10680-10694, 2022 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-36169232

RESUMO

Condensin I and condensin II are multi-subunit complexes that are known for their individual roles in genome organization and preventing genomic instability. However, interactions between condensin I and condensin II subunits and cooperative roles for condensin I and condensin II, outside of their genome organizing functions, have not been reported. We previously discovered that condensin II cooperates with Gamma Interferon Activated Inhibitor of Translation (GAIT) proteins to associate with Long INterspersed Element-1 (LINE-1 or L1) RNA and repress L1 protein expression and the retrotransposition of engineered L1 retrotransposition in cultured human cells. Here, we report that the L1 3'UTR is required for condensin II and GAIT association with L1 RNA, and deletion of the L1 RNA 3'UTR results in increased L1 protein expression and retrotransposition. Interestingly, like condensin II, we report that condensin I also binds GAIT proteins, associates with the L1 RNA 3'UTR, and represses L1 retrotransposition. We provide evidence that the condensin I protein, NCAPD2, is required for condensin II and GAIT protein association with L1 RNA. Furthermore, condensin I and condensin II subunits interact to form a L1-dependent super condensin complex (SCC) which is located primarily within the cytoplasm of both transformed and primary epithelial cells. These data suggest that increases in L1 expression in epithelial cells promote cytoplasmic condensin protein associations that facilitate a feedback loop in which condensins may cooperate to mediate L1 repression.


Assuntos
Elementos Nucleotídeos Longos e Dispersos , Complexos Multiproteicos/metabolismo , Regiões 3' não Traduzidas , Adenosina Trifosfatases/genética , Adenosina Trifosfatases/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Proteínas de Ligação a DNA , Humanos , Interferon gama/genética , Proteínas de Ligação a Poli-ADP-Ribose/genética
2.
FASEB J ; 36(5): e22290, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35344227

RESUMO

The actomyosin cytoskeleton serves as a key regulator of the integrity and remodeling of epithelial barriers by controlling assembly and functions of intercellular junctions and cell-matrix adhesions. Although biochemical mechanisms that regulate the activity of non-muscle myosin II (NM-II) in epithelial cells have been extensively investigated, little is known about assembly of the contractile myosin structures at the epithelial adhesion sites. UNC-45A is a cytoskeletal chaperone that is essential for proper folding of NM-II heavy chains and myofilament assembly. We found abundant expression of UNC-45A in human intestinal epithelial cell (IEC) lines and in the epithelial layer of the normal human colon. Interestingly, protein level of UNC-45A was decreased in colonic epithelium of patients with ulcerative colitis. CRISPR/Cas9-mediated knock-out of UNC-45A in HT-29cf8 and SK-CO15 IEC disrupted epithelial barrier integrity, impaired assembly of epithelial adherence and tight junctions and attenuated cell migration. Consistently, decreased UNC-45 expression increased permeability of the Drosophila gut in vivo. The mechanisms underlying barrier disruptive and anti-migratory effects of UNC-45A depletion involved disorganization of the actomyosin bundles at epithelial junctions and the migrating cell edge. Loss of UNC-45A also decreased contractile forces at apical junctions and matrix adhesions. Expression of deletion mutants revealed roles for the myosin binding domain of UNC-45A in controlling IEC junctions and motility. Our findings uncover a novel mechanism that regulates integrity and restitution of the intestinal epithelial barrier, which may be impaired during mucosal inflammation.


Assuntos
Actomiosina , Miosinas , Actomiosina/metabolismo , Células Epiteliais/metabolismo , Humanos , Junções Intercelulares/metabolismo , Mucosa Intestinal/metabolismo , Chaperonas Moleculares/metabolismo , Miosinas/metabolismo , Junções Íntimas/metabolismo
3.
Gastrointest Endosc ; 98(5): 797-802, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37356633

RESUMO

BACKGROUND AND AIMS: Colonoscopy quality affects colorectal cancer (CRC) incidence and mortality. The U.S. Multi-Society Task Force on Colorectal Cancer strongly recommends photodocumentation (PD) of lesions ≥10 mm in size (ie, large polyps [LPs]) pre-resection and suggests PD postresection to enhance the quality of colonoscopy. No studies have assessed the frequency of LP PD. We evaluated the frequency of and factors associated with PD of LPs. METHODS: Reports from endoscopists performing ≥50 colonoscopies with LP resection between 2016 and 2021 were reviewed. The frequency of LP PD pre-resection and post-resection and factors associated with PD were collected. A composite score of 2 quality metrics (PD of completeness of examination and bowel preparation quality) was created. Endoscopists were divided into 2 tiers based on the frequency of the score on all included examinations: Tier 1, ≥95% of examinations; and Tier 2, <95% of examinations. Univariate and multivariate analyses were used to assess factors associated with PD. RESULTS: A total of 1322 colonoscopies, 1693 LPs, and 25 endoscopists were included in this study. PD of LPs occurred in 1392 (82%) pre-resection and in 878 (52%) post-resection. Factors associated with pre-resection PD include endoscopist subspecialty (colorectal surgery vs gastroenterology: odds ratio [OR], .12; 95% confidence interval [CI], .04-.42); >1 LP on examination (2 vs 1 LP: OR, .41 [95% CI, .27-.61]; and ≥3 vs 1 LP: OR, .41 [95% CI, .24-.70]), and longer withdrawal time (OR, 1.02; 95% CI, 1.01-1.04). CONCLUSIONS: We provide the first data on PD of LP pre-resection and post-resection, which can inform future benchmarking in this area. The implications of PD on metachronous advanced neoplasia need to be studied.

4.
Front Cell Dev Biol ; 12: 1405454, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39040043

RESUMO

The actin cytoskeleton regulates the integrity and repair of epithelial barriers by mediating the assembly of tight junctions (TJs), and adherens junctions (AJs), and driving epithelial wound healing. Actin filaments undergo a constant turnover guided by numerous actin-binding proteins, however, the roles of actin filament dynamics in regulating intestinal epithelial barrier integrity and repair remain poorly understood. Coactosin-like protein 1 (COTL1) is a member of the ADF/cofilin homology domain protein superfamily that binds and stabilizes actin filaments. COTL1 is essential for neuronal and cancer cell migration, however, its functions in epithelia remain unknown. The goal of this study is to investigate the roles of COTL1 in regulating the structure, permeability, and repair of the epithelial barrier in human intestinal epithelial cells (IEC). COTL1 was found to be enriched at apical junctions in polarized IEC monolayers in vitro. The knockdown of COTL1 in IEC significantly increased paracellular permeability, impaired the steady state TJ and AJ integrity, and attenuated junctional reassembly in a calcium-switch model. Consistently, downregulation of COTL1 expression in Drosophila melanogaster increased gut permeability. Loss of COTL1 attenuated collective IEC migration and decreased cell-matrix attachment. The observed junctional abnormalities in COTL1-depleted IEC were accompanied by the impaired assembly of the cortical actomyosin cytoskeleton. Overexpression of either wild-type COTL1 or its actin-binding deficient mutant tightened the paracellular barrier and activated junction-associated myosin II. Furthermore, the actin-uncoupled COTL1 mutant inhibited epithelial migration and matrix attachment. These findings highlight COTL1 as a novel regulator of the intestinal epithelial barrier integrity and repair.

5.
Front Chem ; 12: 1370667, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38817442

RESUMO

This work successfully demonstrates a sustainable and environmentally friendly approach for synthesizing Semal-ZnO nanoparticles (NPs) using the aqueous leaf extract of Bombax ceiba L. These NPs exhibit an absorption peak at approximately 390 nm in the UV-visible spectrum and an energy gap (Eg) of 3.11 eV. Detailed analyses of the morphology and particle size using various spectroscopic and microscopic techniques, XRD, FE-SEM with EDS, and HR-TEM reveal crystallographic peaks attributable to the hexagonal phase, with an average crystal size of 17 nm. The Semal-ZnO NPs also exhibit a notable photocatalytic efficiency for degrading methylene blue (MB) and methyl orange (MO) under sunlight in different water samples collected from diverse natural sources, indicating that they are promising photocatalysts for environmental remediation. The photocatalytic efficiency of the biofabricated Semal-ZnO NPs is impressive, exhibiting a photodegradation rate of up to 99% for MB and 79% for MO in different water samples under exposure to sunlight. The novel phytofabricated Semal-ZnO NPs are thus a beacon of hope for the environment, with their desirable photocatalytic efficiency, pseudo-first-order kinetics, and ability to break down noxious dye pollutants in various aquatic environments.

6.
Eur J Gastroenterol Hepatol ; 36(2): 190-196, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38131425

RESUMO

OBJECTIVE: The purpose of this study was to determine how thromboelastography (TEG) parameters differ by various clinical conditions that commonly occur in patients with cirrhosis, including sepsis, acute on chronic liver failure (ACLF), alcohol-associated hepatitis (AAH) and portal vein thrombosis (PVT). BACKGROUND: TEG, a whole blood assay, is used to assess several parameters of coagulation and is becoming increasingly used in clinical practice. STUDY: This study was a retrospective chart review of 155 patients admitted to the ICU with decompensated cirrhosis from 2017 to 2019. RESULTS: The R time was significantly shorter in patients when they were septic compared to when they were not and longer in patients with vs. without ACLF grade 3. Alpha angle and maximum amplitude was decreased in patients with severe AAH compared to those without severe AAH; and maximum amplitude was increased in patients with acute PVT compared to those with chronic PVT. R time was positively correlated with Chronic Liver Failure Consortium Organ Failure and Chronic Liver Failure Consortium ACLF scores (rho = 0.22, P = 0.020), while alpha angle and maximum amplitude were negatively correlated with MELD-NA. CONCLUSION: Findings suggest TEG parameters vary in several clinical conditions in patients with decompensated cirrhosis who are admitted to the ICU. Prospective research is needed to confirm our findings and to determine how this knowledge can be used to guide clinical practice, as well as blood product transfusions in the setting of bleeding or prior to invasive procedures.


Assuntos
Insuficiência Hepática Crônica Agudizada , Doença Hepática Terminal , Humanos , Tromboelastografia , Estudos Retrospectivos , Estudos Prospectivos , Doença Hepática Terminal/diagnóstico , Estado Terminal , Cirrose Hepática/complicações , Cirrose Hepática/diagnóstico
7.
Transplantation ; 107(4): 849-854, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36445920

RESUMO

The dearth of deceased liver donors has created a supply demand gap, necessitating creation of living donor liver transplantation. However, living donor liver transplantation has relied on directed donation, whereby many potential directed donors are rejected based on ABO blood group incompatibility, hepatic size incompatibility, or the need for biliary or arterial reconstruction during transplant surgery. Much like kidney paired exchange, liver paired exchange (LPE) circumvents these incompatibility issues by relying on anonymous, nondirected, or bridge donors that are better anatomical or histological matches for recipients. Although Asia has taken the lead in LPE, the process has only recently been adopted in North America, with the first successful surgery done in the United States in 2019. Our review article sheds light on the process of LPE and the success of LPE in the United States thus far and, additionally, highlights the several logistical and ethical challenges that must be considered as transplant centers adopt and scale up LPE across the United States to address the increased demand for liver allografts.


Assuntos
Transplante de Rim , Transplante de Fígado , Obtenção de Tecidos e Órgãos , Humanos , Estados Unidos , Doadores Vivos , Fígado/cirurgia , Medo
8.
World J Clin Oncol ; 13(6): 540-552, 2022 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-35949429

RESUMO

BACKGROUND: Epstein-Barr virus associated smooth muscle tumor (EBV-SMT) is a rare oncological entity. However, there is an increasing incidence of EBV-SMTs, as the frequency of organ transplantation and immunosuppression grows. EBV-SMT diagnosis relies on histopathology and immunochemical staining to distinguish it from post-transplant lymphoproliferative disorder (PTLD). There is no clear consensus on the treatment of EBV-SMTs. However, surgical resection, chemotherapy, radiation therapy, and immunosuppression reduction have been explored with varying degrees of success. CASE SUMMARY: Our case series includes six cases of EBV-SMTs across different age groups, with different treatment modalities, adding to the limited existing literature on this rare tumor. The median latency time between immunosuppression and disease diagnosis is four years. EBV-SMTs present with variable degrees of aggressiveness and seem to have worse clinical outcomes in patients with tumor multiplicity and worse immunocompetency. CONCLUSION: It is imperative to continue building on this knowledge and keeping EBV-SMTs on the differential in immunocompromised individuals.

9.
10.
Vaccine ; 35(40): 5352-5359, 2017 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-28863869

RESUMO

BACKGROUND: Maternal immunization against pertussis is a potential strategy to protect young infants from severe disease. We assessed factors associated with intention to accept pertussis vaccination among pregnant women in Karachi, Pakistan. METHODS: We conducted a cross-sectional survey between May and August 2013 in pregnant women who visited healthcare centers in urban slums of Karachi city. Women completed a survey examining socio-demographic factors, vaccination history, knowledge on pertussis disease, perception of vaccine recommendation sources, and potential influences on vaccine decision-making. RESULTS: Of the 283 participants, 259 (92%) provided their intention to either accept or decline pertussis vaccination. Eighty-three percent women were willing to accept the pertussis vaccine if offered during pregnancy. About half (53%) of the participants had ever heard of pertussis disease. Perceptions of pertussis vaccine efficacy, safety, and disease susceptibility were strongly associated with intention to accept pertussis vaccine (p<0.01). Healthcare providers, Ministry of Health, and mass media were considered as highly reliable sources of vaccine recommendation and associated with intention to accept antenatal pertussis vaccination (p<0.001). Healthcare provider recommendation was a common reason cited by respondents for pregnant women to accept antenatal pertussis vaccination (p=0.0005). However, opinion of primary decision-makers in the family (husbands and in-laws) was a crucial reason cited by respondents for pregnant women to reject pertussis vaccination in pregnancy (p=0.003). CONCLUSION: Antenatal pertussis vaccination initiatives in South Asia should strongly consider inclusion of family members, healthcare providers, national health ministries, and mass media to help implement new vaccination programs.


Assuntos
Vacina contra Coqueluche/uso terapêutico , Coqueluche/prevenção & controle , Adulto , Estudos Transversais , Feminino , Humanos , Programas de Imunização , Paquistão , Aceitação pelo Paciente de Cuidados de Saúde , Gravidez , Fatores Socioeconômicos , Coqueluche/imunologia , Adulto Jovem
11.
Vaccine ; 33(39): 5103-9, 2015 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-26296492

RESUMO

BACKGROUND: Facilitators and barriers to influenza vaccination among pregnant women in the developing world are poorly understood, particularly in South Asia. We assessed intention to accept influenza vaccine among ethnically diverse low-income pregnant women in Pakistan. METHODS: From May to August 2013, we conducted a cross-sectional survey of pregnant women who visited health centers in urban slums in Karachi city. We assessed intention to accept influenza vaccine against socio-demographic factors, vaccination history, vaccine recommendation sources, and other factors. RESULTS: In an unvaccinated study population of 283 respondents, 87% were willing to accept the vaccine, if offered. All except two participants were aware of symptoms typically associated with influenza. Perceived vaccine safety, efficacy, and disease susceptibility were significantly associated with intention to accept influenza vaccine (p<0.05). Regardless of intention to accept influenza vaccine, 96% rated healthcare providers as highly reliable source of vaccine information. While a recommendation from a physician was critical for influenza vaccine acceptance, parents-in-law and husbands were often considered the primary decision-makers for pregnant women seeking healthcare including vaccination. CONCLUSIONS: Maternal influenza vaccination initiatives in South Asia should strongly consider counseling of key familial decision-makers and inclusion of healthcare providers to help implement new vaccination programs.


Assuntos
Vacinas contra Influenza/administração & dosagem , Influenza Humana/prevenção & controle , Aceitação pelo Paciente de Cuidados de Saúde , Adolescente , Adulto , Estudos Transversais , Feminino , Hospitais , Humanos , Pessoa de Meia-Idade , Paquistão , Áreas de Pobreza , Gravidez , Fatores Socioeconômicos , Adulto Jovem
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