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1.
Biomed Pharmacother ; 176: 116758, 2024 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-38796972

RESUMEN

Sorafenib (BAY 43-9006) was developed as a multi-kinase inhibitor to treat advanced renal cell, hepatocellular, and thyroid cancers. The cytotoxic effect of sorafenib on cancer cells results from not only inhibiting the MEK/ERK signaling pathway (the on-target effect) but also inducing oxidative damage (the off-target effect). The inhibitory effect of sorafenib on system Xc- (xCT), a cystine/glutamate antiporter, promotes ferroptosis induction and accounts for oxidative damage. While emerging studies on ferroptosis in cancers have garnered increasing attention, the lack of consideration for ferroptosis inducers (FINs) with favorable pharmacokinetics could be problematic. Herein, we remodeled the chemical structure of sorafenib, of which pharmacokinetics and safety are already assured, to customize the off-target effect (i.e., ferroptosis induction) to on-target by disrupting the adenine-binding motif. JB3, a sorafenib derivative (i.e., JB compounds), with a tenfold higher IC50 toward RAF1 because of chemical remodeling, induced strong cytotoxicity in the elastin-sensitive lung cancer cells, while it was markedly reduced by ferrostatin-1. The 24% oral bioavailability of JB3 in rats accounted for a significant anti-tumor effect of orally administrated JB3 in xenograft models. These results indicate that JB3 could be further developed as an orally bioavailable FIN in novel anti-cancer therapeutics.

2.
Nat Commun ; 15(1): 4002, 2024 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-38734692

RESUMEN

Precise genome editing is crucial for establishing isogenic human disease models and ex vivo stem cell therapy from the patient-derived hPSCs. Unlike Cas9-mediated knock-in, cytosine base editor and prime editor achieve the desirable gene correction without inducing DNA double strand breaks. However, hPSCs possess highly active DNA repair pathways and are particularly susceptible to p53-dependent cell death. These unique characteristics impede the efficiency of gene editing in hPSCs. Here, we demonstrate that dual inhibition of p53-mediated cell death and distinct activation of the DNA damage repair system upon DNA damage by cytosine base editor or prime editor additively enhanced editing efficiency in hPSCs. The BE4stem system comprised of p53DD, a dominant negative p53, and three UNG inhibitor, engineered to specifically diminish base excision repair, improves cytosine base editor efficiency in hPSCs. Addition of dominant negative MLH1 to inhibit mismatch repair activity and p53DD in the conventional prime editor system also significantly enhances prime editor efficiency in hPSCs. Thus, combined inhibition of the distinct cellular cascades engaged in hPSCs upon gene editing could significantly enhance precise genome editing in these cells.


Asunto(s)
Sistemas CRISPR-Cas , Daño del ADN , Reparación del ADN , Edición Génica , Proteína p53 Supresora de Tumor , Edición Génica/métodos , Humanos , Proteína p53 Supresora de Tumor/metabolismo , Proteína p53 Supresora de Tumor/genética , Línea Celular , Homólogo 1 de la Proteína MutL/genética , Homólogo 1 de la Proteína MutL/metabolismo , Citosina/metabolismo
3.
Microbiol Spectr ; 12(4): e0337223, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38466127

RESUMEN

Foot-and-mouth disease (FMD) is one of the most devastating diseases of livestock which can cause significant economic losses, especially when introduced to FMD-free countries. FMD virus (FMDV) belongs to the family Picornaviridae and is antigenically heterogeneous with seven established serotypes. The prevailing preventive and control strategies are limited to restriction of animal movement and elimination of infected or exposed animals, which can be potentially combined with vaccination. However, FMD vaccination has limitations including delayed protection and lack of cross-protection against different serotypes. Recently, antiviral drug use for FMD outbreaks has increasingly been recognized as a potential tool to augment the existing early response strategies, but limited research has been reported on potential antiviral compounds for FMDV. FMDV 3C protease (3Cpro) cleaves the viral-encoded polyprotein into mature and functional proteins during viral replication. The essential role of viral 3Cpro in viral replication and the high conservation of 3Cpro among different FMDV serotypes make it an excellent target for antiviral drug development. We have previously reported multiple series of inhibitors against picornavirus 3Cpro or 3C-like proteases (3CLpros) encoded by coronaviruses or caliciviruses. In this study, we conducted structure-activity relationship studies for our in-house focused compound library containing 3Cpro or 3CLpro inhibitors against FMDV 3Cpro using enzyme and cell-based assays. Herein, we report the discovery of aldehyde and α-ketoamide inhibitors of FMDV 3Cpro with high potency. These data inform future preclinical studies that are related to the advancement of these compounds further along the drug development pathway.IMPORTANCEFood-and-mouth disease (FMD) virus (FMDV) causes devastating disease in cloven-hoofed animals with a significant economic impact. Emergency response to FMD outbreaks to limit FMD spread is critical, and the use of antivirals may overcome the limitations of existing control measures by providing immediate protection for susceptible animals. FMDV encodes 3C protease (3Cpro), which is essential for virus replication and an attractive target for antiviral drug discovery. Here, we report a structure-activity relationship study on multiple series of protease inhibitors and identified potent inhibitors of FMDV 3Cpro. Our results suggest that these compounds have the potential for further development as FMD antivirals.


Asunto(s)
Virus de la Fiebre Aftosa , Fiebre Aftosa , Animales , Virus de la Fiebre Aftosa/metabolismo , Péptido Hidrolasas/metabolismo , Serogrupo , Fiebre Aftosa/tratamiento farmacológico , Fiebre Aftosa/prevención & control , Endopeptidasas/metabolismo , Proteasas Virales 3C , Antivirales/farmacología
4.
Cell Mol Life Sci ; 81(1): 38, 2024 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-38214772

RESUMEN

During in vitro culture, human pluripotent stem cells (hPSCs) often acquire survival advantages characterized by decreased susceptibility to mitochondrial cell death, known as "culture adaptation." This adaptation is associated with genetic and epigenetic abnormalities, including TP53 mutations, copy number variations, trisomy, and methylation changes. Understanding the molecular mechanisms underlying this acquired survival advantage is crucial for safe hPSC-based cell therapies. Through transcriptome and methylome analysis, we discovered that the epigenetic repression of CHCHD2, a mitochondrial protein, is a common occurrence during in vitro culture using enzymatic dissociation. We confirmed this finding through genetic perturbation and reconstitution experiments in normal human embryonic stem cells (hESCs). Loss of CHCHD2 expression conferred resistance to single cell dissociation-induced cell death, a common stress encountered during in vitro culture. Importantly, we found that the downregulation of CHCHD2 significantly attenuates the activity of Rho-associated protein kinase (ROCK), which is responsible for inducing single cell death in hESCs. This suggests that hESCs may survive routine enzyme-based cell dissociation by downregulating CHCHD2 and thereby attenuating ROCK activity. These findings provide insights into the mechanisms by which hPSCs acquire survival advantages and adapt to in vitro culture conditions.


Asunto(s)
Células Madre Embrionarias Humanas , Células Madre Pluripotentes , Humanos , Línea Celular , Represión Epigenética , Variaciones en el Número de Copia de ADN , Células Madre Embrionarias Humanas/metabolismo , Diferenciación Celular , Supervivencia Celular , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
5.
mBio ; 15(2): e0287823, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38126789

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and Middle East respiratory syndrome coronavirus (MERS-CoV) are zoonotic betacoronaviruses that continue to have a significant impact on public health. Timely development and introduction of vaccines and antivirals against SARS-CoV-2 into the clinic have substantially mitigated the burden of COVID-19. However, a limited or lacking therapeutic arsenal for SARS-CoV-2 and MERS-CoV infections, respectively, calls for an expanded and diversified portfolio of antivirals against these coronavirus infections. In this report, we examined the efficacy of two potent 3CLpro inhibitors, 5d and 11d, in fatal animal models of SARS-CoV-2 and MERS-CoV to demonstrate their broad-spectrum activity against both viral infections. These compounds significantly increased the survival of mice in both models when treatment started 1 day post infection compared to no treatment which led to 100% fatality. Especially, the treatment with compound 11d resulted in 80% and 90% survival in SARS-CoV-2 and MERS-CoV-infected mice, respectively. Amelioration of lung viral load and histopathological changes in treated mice correlated well with improved survival in both infection models. Furthermore, compound 11d exhibited significant antiviral activities in K18-hACE2 mice infected with SARS-CoV-2 Omicron subvariant XBB.1.16. The results suggest that these are promising candidates for further development as broad-spectrum direct-acting antivirals against highly virulent human coronaviruses.IMPORTANCEHuman coronaviruses such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and Middle East respiratory syndrome coronavirus (MERS-CoV) continue to have a significant impact on public health. A limited or lacking therapeutic arsenal for SARS-CoV-2 and MERS-CoV infections calls for an expanded and diversified portfolio of antivirals against these coronavirus infections. We have previously reported a series of small-molecule 3C-like protease (3CLpro) inhibitors against human coronaviruses. In this report, we demonstrated the in vivo efficacy of 3CLpro inhibitors for their broad-spectrum activity against both SARS-CoV-2 and MERS-CoV infections using the fatal animal models. The results suggest that these are promising candidates for further development as broad-spectrum direct-acting antivirals against highly virulent human coronaviruses.


Asunto(s)
COVID-19 , Hepatitis C Crónica , Coronavirus del Síndrome Respiratorio de Oriente Medio , Humanos , Ratones , Animales , SARS-CoV-2 , Antivirales/farmacología , Antivirales/uso terapéutico , Modelos Animales de Enfermedad
6.
Proc Natl Acad Sci U S A ; 120(39): e2303455120, 2023 09 26.
Artículo en Inglés | MEDLINE | ID: mdl-37722054

RESUMEN

Cows produce antibodies with a disulfide-bonded antigen-binding domain embedded within ultralong heavy chain third complementarity determining regions. This "knob" domain is analogous to natural cysteine-rich peptides such as knottins in that it is small and stable but can accommodate diverse loops and disulfide bonding patterns. We immunized cattle with SARS-CoV-2 spike and found ultralong CDR H3 antibodies that could neutralize several viral variants at picomolar IC50 potencies in vitro and could protect from disease in vivo. The independent CDR H3 peptide knobs were expressed and maintained the properties of the parent antibodies. The knob interaction with SARS-CoV-2 spike was revealed by electron microscopy, X-ray crystallography, NMR spectroscopy, and mass spectrometry and established ultralong CDR H3-derived knobs as the smallest known recombinant independent antigen-binding fragment. Unlike other vertebrate antibody fragments, these knobs are not reliant on the immunoglobulin domain and have potential as a new class of therapeutics.


Asunto(s)
COVID-19 , SARS-CoV-2 , Femenino , Animales , Bovinos , Anticuerpos , Fragmentos Fab de Inmunoglobulinas/genética , Disulfuros
7.
Int J Mol Sci ; 24(16)2023 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-37628753

RESUMEN

GV1001, a 16 amino acid peptide derived from the catalytic segment of human telomerase reverse transcriptase, was developed as an anti-cancer vaccine. Subsequently, it was found to exhibit anti-inflammatory and anti-Alzheimer's disease properties. Periodontitis is a risk factor for a variety of systemic diseases, including atherosclerosis, a process in which chronic systemic and vascular inflammation results in the formation of plaques containing lipids, macrophages, foam cells, and tissue debris on the vascular intima. Thus, we investigated the effect of GV1001 on the severity of ligature-induced periodontitis, vascular inflammation, and arterial lipid deposition in mice. GV1001 notably reduced the severity of ligature-induced periodontitis by inhibiting gingival and systemic inflammation, alveolar bone loss, and vascular inflammation in wild-type mice. It also significantly lowered the amount of lipid deposition in the arterial wall in ApoE-deficient mice receiving ligature placement without changing the serum lipid profile. In vitro, we found that GV1001 inhibited the Receptor Activator of NF-κB ligand (RANKL)-induced osteoclast formation and tumor necrosis factor-α (TNF-α)-induced phenotypic changes in endothelial cells. In conclusion, our study suggests that GV1001 prevents the exacerbation of periodontitis and atherosclerosis associated with periodontitis partly by inhibiting local, systemic, and vascular inflammation and phenotypic changes of vascular endothelial cells.


Asunto(s)
Aterosclerosis , Vacunas contra el Cáncer , Periodontitis , Humanos , Animales , Ratones , Células Endoteliales , Arterias , Inflamación , Vacunas de Subunidad
8.
Cells ; 12(12)2023 06 11.
Artículo en Inglés | MEDLINE | ID: mdl-37371075

RESUMEN

Adoptive cell therapy using chimeric antigen receptor (CAR) technology is one of the most advanced engineering platforms for cancer immunotherapy. CAR-T cells have shown remarkable efficacy in the treatment of hematological malignancies. However, their limitations in solid tumors include an immunosuppressive tumor microenvironment (TME), insufficient tumor infiltration, toxicity, and the absence of tumor-specific antigens. Although recent advances in CAR-T cell design-such as the incorporation of co-stimulatory domains and the development of armored CAR-T cells-have shown promising results in treating solid tumors, there are still challenges that need to be addressed. To overcome these limitations, other immune cells, such as natural killer (NK) cells and macrophages (M), have been developed as attractive options for efficient cancer immunotherapy of solid tumors. CAR-NK cells exhibit substantial clinical improvements with "off-the-shelf" availability and low toxicity. CAR-M cells have promising therapeutic potential because macrophages can infiltrate the TME of solid tumors. Here, we review the recent advances and future perspectives associated with engineered immune cell-based cancer immunotherapies for solid tumors. We also summarize ongoing clinical trials investigating the safety and efficacy of engineered immune cells, such as CAR-T, CAR-NK, and CAR-M, for targeting solid tumors.


Asunto(s)
Neoplasias , Receptores Quiméricos de Antígenos , Humanos , Receptores Quiméricos de Antígenos/metabolismo , Inmunoterapia Adoptiva/métodos , Neoplasias/patología , Inmunoterapia/métodos , Linfocitos T , Antígenos de Neoplasias/metabolismo , Microambiente Tumoral
9.
Mol Ther Nucleic Acids ; 32: 914-922, 2023 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-37346976

RESUMEN

Precise genome editing in human pluripotent stem cells (hPSCs) has potential applications in isogenic disease modeling and ex vivo stem cell therapy, necessitating diverse genome editing tools. However, unlike differentiated somatic cells, hPSCs have unique cellular properties that maintain genome integrity, which largely determine the overall efficiency of an editing tool. Considering the high demand for prime editors (PEs), it is imperative to characterize the key molecular determinants of PE outcomes in hPSCs. Through homozygous knockout (KO) of MMR pathway key proteins MSH2, MSH3, and MSH6, we reveal that MutSα and MutSß determine PE efficiency in an editing size-dependent manner. Notably, MSH2 perturbation disrupted both MutSα and MutSß complexes, dramatically escalating PE efficiency from base mispair to 10 bases, up to 50 folds. Similarly, impaired MutSα by MSH6 KO improved editing efficiency from single to three base pairs, while defective MutSß by MSH3 KO heightened efficiency from three to 10 base pairs. Thus, the size-dependent effect of MutSα and MutSß on prime editing implies that MMR is a vital PE efficiency determinant in hPSCs and highlights the distinct roles of MutSα and MutSß in its outcome.

10.
Anim Dis ; 3(1): 12, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37128508

RESUMEN

The spike protein (S) of SARS-CoV-2 is responsible for viral attachment and entry, thus a major factor for host susceptibility, tissue tropism, virulence and pathogenicity. The S is divided with S1 and S2 region, and the S1 contains the receptor-binding domain (RBD), while the S2 contains the hydrophobic fusion domain for the entry into the host cell. Numerous host proteases have been implicated in the activation of SARS-CoV-2 S through various cleavage sites. In this article, we review host proteases including furin, trypsin, transmembrane protease serine 2 (TMPRSS2) and cathepsins in the activation of SARS-CoV-2 S. Many betacoronaviruses including SARS-CoV-2 have polybasic residues at the S1/S2 site which is subjected to the cleavage by furin. The S1/S2 cleavage facilitates more assessable RBD to the receptor ACE2, and the binding triggers further conformational changes and exposure of the S2' site to proteases such as type II transmembrane serine proteases (TTPRs) including TMPRSS2. In the presence of TMPRSS2 on the target cells, SARS-CoV-2 can utilize a direct entry route by fusion of the viral envelope to the cellular membrane. In the absence of TMPRSS2, SARS-CoV-2 enter target cells via endosomes where multiple cathepsins cleave the S for the successful entry. Additional host proteases involved in the cleavage of the S were discussed. This article also includes roles of 3C-like protease inhibitors which have inhibitory activity against cathepsin L in the entry of SARS-CoV-2, and discussed the dual roles of such inhibitors in virus replication.

11.
Eur J Med Chem ; 254: 115376, 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-37080108

RESUMEN

The high morbidity and mortality associated with SARS-CoV-2 infection, the etiological agent of COVID-19, has had a major impact on global public health. Significant progress has been made in the development of an array of vaccines and biologics, however, the emergence of SARS-CoV-2 variants and breakthrough infections are an ongoing major concern. Furthermore, there is an existing paucity of small-molecule host and virus-directed therapeutics and prophylactics that can be used to counter the spread of SARS-CoV-2, and any emerging and re-emerging coronaviruses. We describe herein our efforts to address this urgent need by focusing on the structure-guided design of potent broad-spectrum inhibitors of SARS-CoV-2 3C-like protease (3CLpro or Main protease), an enzyme essential for viral replication. The inhibitors exploit the directional effects associated with the presence of a gem-dimethyl group that allow the inhibitors to optimally interact with the S4 subsite of the enzyme. Several compounds were found to potently inhibit SARS-CoV-2 and MERS-CoV 3CL proteases in biochemical and cell-based assays. Specifically, the EC50 values of aldehyde 1c and its corresponding bisulfite adduct 1d against SARS-CoV-2 were found to be 12 and 10 nM, respectively, and their CC50 values were >50 µM. Furthermore, deuteration of these compounds yielded compounds 2c/2d with EC50 values 11 and 12 nM, respectively. Replacement of the aldehyde warhead with a nitrile (CN) or an α-ketoamide warhead or its corresponding bisulfite adduct yielded compounds 1g, 1eand1f with EC50 values 60, 50 and 70 nM, respectively. High-resolution cocrystal structures have identified the structural determinants associated with the binding of the inhibitors to the active site of the enzyme and, furthermore, have illuminated the mechanism of action of the inhibitors. Overall, the high Safety Index (SI) (SI=CC50/EC50) displayed by these compounds suggests that they are well-suited to conducting further preclinical studies.


Asunto(s)
COVID-19 , Hepatitis C Crónica , Coronavirus del Síndrome Respiratorio de Oriente Medio , Humanos , SARS-CoV-2/metabolismo , Antivirales/farmacología , Antivirales/química , Péptido Hidrolasas , Inhibidores de Proteasas/farmacología , Inhibidores de Proteasas/química , Cisteína Endopeptidasas/metabolismo
12.
Stem Cell Rev Rep ; 19(5): 1466-1481, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36862329

RESUMEN

BACKGROUND: Despite highly effective machinery for the maintenance of genome integrity in human embryonic stem cells (hESCs), the frequency of genetic aberrations during in-vitro culture has been a serious issue for future clinical applications. METHOD: By passaging hESCs over a broad range of timepoints (up to 6 years), the isogenic hESC lines with different passage numbers with distinct cellular characteristics, were established. RESULT: We found that mitotic aberrations, such as the delay of mitosis, multipolar centrosomes, and chromosome mis-segregation, were increased in parallel with polyploidy compared to early-passaged hESCs (EP-hESCs) with normal copy number. Through high-resolution genome-wide approaches and transcriptome analysis, we found that culture adapted-hESCs with a minimal amplicon in chromosome 20q11.21 highly expressed TPX2, a key protein for governing spindle assembly and cancer malignancy. Consistent with these findings, the inducible expression of TPX2 in EP-hESCs reproduced aberrant mitotic events, such as the delay of mitotic progression, spindle stabilization, misaligned chromosomes, and polyploidy. CONCLUSION: These studies suggest that the increased transcription of TPX2 in culture adapted hESCs could contribute to an increase in aberrant mitosis due to altered spindle dynamics.


Asunto(s)
Células Madre Embrionarias Humanas , Humanos , Células Madre Embrionarias Humanas/metabolismo , Mitosis/genética , Proteínas de Ciclo Celular/genética , Ciclo Celular , Poliploidía , Proteínas Asociadas a Microtúbulos/genética , Proteínas Asociadas a Microtúbulos/metabolismo
13.
Artículo en Inglés | MEDLINE | ID: mdl-36871246

RESUMEN

OBJECTIVE: Rivaroxaban is a direct factor Xa inhibitor used for the prevention and treatment of thromboembolic disorders. The objective of this study was to compare the pharmacokinetic profiles of two rivaroxaban formulations after a single dose of rivaroxaban (2.5-mg tablet) in healthy Korean subjects. MATERIALS AND METHODS: This study was a randomized, open-label, single-dose, two-period, crossover study that included 34 healthy adult subjects under fasting conditions. The test drug (Yuhan rivaroxaban tablet) or reference drug (Xarelto tablet) was administered in each period. Serial blood samples were collected up to 36 hours post-dose. Plasma concentrations were measured by LC-MS/MS. Pharmacokinetic parameters, including maximum plasma concentration (Cmax) and area under the plasma concentration-time curve from time zero to the last measurable concentration (AUCt), were determined by non-compartmental analysis. The 90% confidence intervals (CIs) for the ratio of the geometric means of Cmax and AUCt for the test drug/reference drug were calculated to evaluate pharmacokinetic equivalence. RESULTS: A total of 28 subjects were included in the pharmacokinetic analysis. The geometric mean ratios (90% CI) of the test drug/reference drug for rivaroxaban were 1.0140 (0.9794 - 1.0499) for AUCt and 0.9350 (0.8797 - 0.9939) for Cmax. All adverse events (AEs) were mild, and there was no significant difference in the incidence of AEs between the formulations. CONCLUSION: The pharmacokinetic parameters of rivaroxaban were compared between the test and reference drug, and both formulations were bioequivalent. The newly developed rivaroxaban tablet is safe and well tolerated as the reference drug (ClinicalTrials.gov identifiers: NCT05418803).

14.
ACS Pharmacol Transl Sci ; 6(1): 181-194, 2023 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-36654747

RESUMEN

The advent of SARS-CoV-2, the causative agent of COVID-19, and its worldwide impact on global health, have provided the impetus for the development of effective countermeasures that can be deployed against the virus, including vaccines, monoclonal antibodies, and direct-acting antivirals (DAAs). Despite these efforts, the current paucity of DAAs has created an urgent need for the creation of an enhanced and diversified portfolio of broadly acting agents with different mechanisms of action that can effectively abrogate viral infection. SARS-CoV-2 3C-like protease (3CLpro), an enzyme essential for viral replication, is a validated target for the discovery of SARS-CoV-2 therapeutics. In this report, we describe the structure-guided utilization of the cyclopropane moiety in the design of highly potent inhibitors of SARS-CoV-2 3CLpro, SARS-CoV-1 3CLpro, and MERS-CoV 3CLpro. High-resolution cocrystal structures were used to identify the structural determinants associated with the binding of the inhibitors to the active site of the enzyme and unravel the mechanism of action. Aldehydes 5c and 11c inhibited SARS-CoV-2 replication with EC50 values of 12 and 11 nM, respectively. Furthermore, the corresponding aldehyde bisulfite adducts 5d and 11d were equipotent with EC50 values of 13 and 12 nM, respectively. The safety index (SI) values for compounds 5c / 11c and 5d / 11d ranged between 7692 and 9090. Importantly, aldehydes 5c / 11c and bisulfite adducts 5d / 11d potently inhibited MERS-CoV 3CLpro with IC50 values of 80 and 120 nM, and 70 and 70 nM, respectively. Likewise, compounds 5c / 11c and 5d / 11d inhibited SARS-CoV-1 with IC50 values of 960 and 350 nM and 790 and 240 nM, respectively. Taken together, these studies suggest that the inhibitors described herein have low cytotoxicity and high potency and are promising candidates for further development as broad-spectrum direct-acting antivirals against highly pathogenic coronaviruses.

15.
Exp Mol Med ; 55(1): 32-42, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36596852

RESUMEN

Genetic alterations have been reported for decades in most human embryonic stem cells (hESCs). Survival advantage, a typical trait acquired during long-term in vitro culture, results from the induction of BCL2L1 upon frequent copy number variation (CNV) at locus 20q11.21 and is one of the strongest candidates associated with genetic alterations that occur via escape from mitotic stress. However, the underlying mechanisms for BCL2L1 induction remain unknown. Furthermore, abnormal mitosis and the survival advantage that frequently occur in late passage are associated with the expression of BCL2L1, which is in locus 20q11.21. In this study, we demonstrated that the expression of TPX2, a gene located in 20q11.21, led to BCL2L1 induction and consequent survival traits under mitotic stress in isogenic pairs of hESCs and human induced pluripotent stem cells (iPSCs) with normal and 20q11.21 CNVs. High Aurora A kinase activity by TPX2 stabilized the YAP1 protein to induce YAP1-dependent BCL2L1 expression. A chemical inhibitor of Aurora A kinase and knockdown of YAP/TAZ significantly abrogated the high tolerance to mitotic stress through BCL2L1 suppression. These results suggest that the collective expression of TPX2 and BCL2L1 from CNV at loci 20q11.21 and a consequent increase in YAP1 signaling promote genome instability during long-term in vitro hESC culture.


Asunto(s)
Células Madre Embrionarias Humanas , Células Madre Pluripotentes Inducidas , Humanos , Células Madre Embrionarias Humanas/metabolismo , Aurora Quinasa A/genética , Variaciones en el Número de Copia de ADN , Células Madre Pluripotentes Inducidas/metabolismo , Proteína bcl-X/genética , Proteínas Asociadas a Microtúbulos/genética , Proteínas Asociadas a Microtúbulos/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo
16.
Medicina (Kaunas) ; 60(1)2023 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-38256316

RESUMEN

Background and Objectives: The rise in suicidal attempts has led to an increase in unusual intoxication cases. The ingestion of anhydrous calcium chloride (CaCl2) causes direct injury to the gastrointestinal wall via a thermal burn. Therefore, previous reports on CaCl2 ingestion primarily considered the gastrointestinal injury. Severe CaCl2 intoxication can induce a hypercalcemic crisis, presenting with arrhythmia, acute pancreatitis, and acute kidney injury. This case report details a patient with hematemesis and hypercalcemia following the ingestion of a commercial desiccant. We aimed to report the progression of the case, with a focus on the electrocardiographic manifestations. Case Presentation: A 39-year-old female presented at a regional emergency center with blood in her vomit after the ingestion of a commercial desiccant. Bloody emesis was the initial symptom, and various electrolyte imbalances developed during admission. Electrocardiogram (ECG) changes occurred early after hospitalization and disappeared before the electrolyte levels normalized. The patient was maintained in an NPO (Nil Per Os) state throughout her hospital stay. The bloody emesis and abdominal pain resolved quite early, despite her minimal mention of symptoms, possibly due to her suspected negative psychiatric symptoms. Conclusions: In this case, we observed dynamic and prolonged multiple electrolyte imbalances along with the early-phase ECG changes, all of which responded well to supportive care. This report adds to the understanding of the diverse manifestations and management of CaCl2 intoxication.


Asunto(s)
Hipercalcemia , Pancreatitis , Humanos , Femenino , Adulto , Higroscópicos , Enfermedad Aguda , Cloruro de Calcio , Electrólitos , Ingestión de Alimentos , Vómitos/etiología
17.
Viruses ; 14(12)2022 12 12.
Artículo en Inglés | MEDLINE | ID: mdl-36560774

RESUMEN

There is mounting evidence of SARS-CoV-2 spillover from humans into many domestic, companion, and wild animal species. Research indicates that humans have infected white-tailed deer, and that deer-to-deer transmission has occurred, indicating that deer could be a wildlife reservoir and a source of novel SARS-CoV-2 variants. We examined the hypothesis that the Omicron variant is actively and asymptomatically infecting the free-ranging deer of New York City. Between December 2021 and February 2022, 155 deer on Staten Island, New York, were anesthetized and examined for gross abnormalities and illnesses. Paired nasopharyngeal swabs and blood samples were collected and analyzed for the presence of SARS-CoV-2 RNA and antibodies. Of 135 serum samples, 19 (14.1%) indicated SARS-CoV-2 exposure, and 11 reacted most strongly to the wild-type B.1 lineage. Of the 71 swabs, 8 were positive for SARS-CoV-2 RNA (4 Omicron and 4 Delta). Two of the animals had active infections and robust neutralizing antibodies, revealing evidence of reinfection or early seroconversion in deer. Variants of concern continue to circulate among and may reinfect US deer populations, and establish enzootic transmission cycles in the wild: this warrants a coordinated One Health response, to proactively surveil, identify, and curtail variants of concern before they can spill back into humans.


Asunto(s)
COVID-19 , Ciervos , Humanos , Animales , Ciudad de Nueva York/epidemiología , ARN Viral/genética , SARS-CoV-2/genética , COVID-19/epidemiología , COVID-19/veterinaria , Animales Salvajes
19.
J Glob Health ; 12: 04058, 2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-36181506

RESUMEN

Background: Optimal child feeding practices contribute to reducing child undernutrition in low- and middle-income countries. Minimum dietary diversity (MDD) is a key indicator of complementary feeding quality for children aged 6-23 months. We aimed to examine the gender-common and gender-specific factors associated with the failure to meet MDD in eight Asia Pacific countries. Methods: The study used data of children aged 6-23 months from the Demographic and Health Surveys (DHS) conducted in Afghanistan (n = 8410), Bangladesh (n = 2371), Nepal (n = 1478), Pakistan (n = 3490), Cambodia (n = 2182), Indonesia (n = 5133), Myanmar (n = 1379), and Timor-Leste (n = 2115). A total of 41 household, maternal, and child-level variables were examined for association with MDD using univariate and multivariable logistic regressions. All analyses accounted for the survey design and sampling weights. Results: Being aged 6-11 months, not receiving Vitamin A supplementation, low maternal education, belonging to a low wealth quintile, and having two or more young children in the household were factors related to the failure to meet MDD among both male and female children. Mothers' not watching TV or not being exposed to media at least once a week, delivery at home, young age, and engagement to non-agricultural work were only significant risk factors among female children. Non-professional delivery assistance, unsafe disposal of children's stool, tolerant attitudes towards domestic violence, and rural residence were significant factors only among male children. Conclusions: It is possible that male and female children in the region may consume food in various ways, because the factors for meeting MDD are not the same for different genders of children. It is advised to enhance dietary diversity in child nutrition programmes through gender-specific activities.


Asunto(s)
Lactancia Materna , Vitamina A , Preescolar , Dieta , Femenino , Humanos , Lactante , Fenómenos Fisiológicos Nutricionales del Lactante , Masculino , Pakistán , Factores Socioeconómicos
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