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1.
Nature ; 582(7813): 586-591, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32494005

RESUMO

Deregulation of metabolism and disruption of genome integrity are hallmarks of cancer1. Increased levels of the metabolites 2-hydroxyglutarate, succinate and fumarate occur in human malignancies owing to somatic mutations in the isocitrate dehydrogenase-1 or -2 (IDH1 or IDH2) genes, or germline mutations in the fumarate hydratase (FH) and succinate dehydrogenase genes (SDHA, SDHB, SDHC and SDHD), respectively2-4. Recent work has made an unexpected connection between these metabolites and DNA repair by showing that they suppress the pathway of homology-dependent repair (HDR)5,6 and confer an exquisite sensitivity to inhibitors of poly (ADP-ribose) polymerase (PARP) that are being tested in clinical trials. However, the mechanism by which these oncometabolites inhibit HDR remains poorly understood. Here we determine the pathway by which these metabolites disrupt DNA repair. We show that oncometabolite-induced inhibition of the lysine demethylase KDM4B results in aberrant hypermethylation of histone 3 lysine 9 (H3K9) at loci surrounding DNA breaks, masking a local H3K9 trimethylation signal that is essential for the proper execution of HDR. Consequently, recruitment of TIP60 and ATM, two key proximal HDR factors, is substantially impaired at DNA breaks, with reduced end resection and diminished recruitment of downstream repair factors. These findings provide a mechanistic basis for oncometabolite-induced HDR suppression and may guide effective strategies to exploit these defects for therapeutic gain.


Assuntos
Cromatina/metabolismo , Reparo do DNA , Recombinação Homóloga , Neoplasias/metabolismo , Transdução de Sinais , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Linhagem Celular Tumoral , Cromatina/efeitos dos fármacos , Quebras de DNA/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Recombinação Homóloga/efeitos dos fármacos , Humanos , Histona Desmetilases com o Domínio Jumonji/antagonistas & inibidores , Lisina Acetiltransferase 5/metabolismo , Metilação/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/patologia , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Transdução de Sinais/efeitos dos fármacos
2.
J Am Chem Soc ; 146(27): 18241-18252, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38815248

RESUMO

Aberrant DNA repair is a hallmark of cancer, and many tumors display reduced DNA repair capacities that sensitize them to genotoxins. Here, we demonstrate that the differential DNA repair capacities of healthy and transformed tissue may be exploited to obtain highly selective chemotherapies. We show that the novel N3-(2-fluoroethyl)imidazotetrazine "KL-50" is a selective toxin toward tumors that lack the DNA repair protein O6-methylguanine-DNA-methyltransferase (MGMT), which reverses the formation of O6-alkylguanine lesions. We establish that KL-50 generates DNA interstrand cross-links (ICLs) by a multistep process comprising DNA alkylation to generate an O6-(2-fluoroethyl)guanine (O6FEtG) lesion, slow unimolecular displacement of fluoride to form an N1,O6-ethanoguanine (N1,O6EtG) intermediate, and ring-opening by the adjacent cytidine. The slow rate of N1,O6EtG formation allows healthy cells expressing MGMT to reverse the initial O6FEtG lesion before it evolves to N1,O6EtG, thereby suppressing the formation of toxic DNA-MGMT cross-links and reducing the amount of DNA ICLs generated in healthy cells. In contrast, O6-(2-chloroethyl)guanine lesions produced by agents such as lomustine and the N3-(2-chloroethyl)imidazotetrazine mitozolomide rapidly evolve to N1,O6EtG, resulting in the formation of DNA-MGMT cross-links and DNA ICLs in healthy tissue. These studies suggest that careful consideration of the rates of chemical DNA modification and biochemical DNA repair may lead to the identification of other tumor-specific genotoxic agents.


Assuntos
Neoplasias Encefálicas , Resistencia a Medicamentos Antineoplásicos , Humanos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Reparo do DNA/efeitos dos fármacos , O(6)-Metilguanina-DNA Metiltransferase/metabolismo , O(6)-Metilguanina-DNA Metiltransferase/antagonistas & inibidores , Imidazóis/química , Imidazóis/farmacologia , Imidazóis/uso terapêutico
3.
Clin Gastroenterol Hepatol ; 22(2): 368-376.e4, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37802268

RESUMO

BACKGROUND & AIMS: The evolution of complicated pediatric Crohn's disease (CD) in the era of anti-tumor necrosis factor (aTNF) therapy continues to be described. Because CD progresses from inflammatory to stricturing (B2) and penetrating (B3) disease behaviors in a subset of patients, we aimed to understand the risk of developing complicated disease behavior or undergoing surgery in relation to aTNF timing and body mass index z-score (BMIz) normalization. METHODS: Multicenter, 5-year longitudinal data from 1075 newly diagnosed CD patients were analyzed. Descriptive statistics, univariate and stepwise multivariate Cox proportional hazard regression (CPHR), and log-rank analyses were performed for risk of surgery and complicated disease behaviors. Differential gene expression from ileal bulk RNA sequencing was correlated with outcomes. RESULTS: Stricturing complications had the largest increase: from 2.98% to 10.60% over 5 years. Multivariate CPHR showed aTNF exposure within 3 months from diagnosis (hazard ratio [HR], 0.33; 95% CI, 0.15-0.71) and baseline L2 disease (HR, 0.29; 95% CI, 0.09-0.92) to be associated with reduced B1 to B2 progression. For children with a low BMIz at diagnosis (n = 294), multivariate CPHR showed BMIz normalization within 6 months of diagnosis (HR, 0.47; 95% CI, 0.26-0.85) and 5-aminosalicyclic acid exposure (HR, 0.32; 95% CI, 0.13-0.81) were associated with a decreased risk for surgery while B2 (HR, 4.20; 95% CI, 1.66-10.65) and B2+B3 (HR, 8.24; 95% CI, 1.08-62.83) at diagnosis increased surgery risk. Patients without BMIz normalization were enriched for genes in cytokine production and inflammation. CONCLUSIONS: aTNF exposure up to 3 months from diagnosis may reduce B2 progression. In addition, lack of BMIz normalization within 6 months of diagnosis is associated with increased surgery risk and a proinflammatory transcriptomic profile.


Assuntos
Doença de Crohn , Criança , Humanos , Índice de Massa Corporal , Fatores de Risco , Doença de Crohn/complicações , Fator de Necrose Tumoral alfa , Constrição Patológica/etiologia , Necrose , Progressão da Doença , Estudos Retrospectivos
4.
Pediatr Crit Care Med ; 25(4): 288-300, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38236083

RESUMO

OBJECTIVES: To characterize immunocompromised-associated pediatric acute respiratory distress syndrome (I-PARDS) and contrast it to PARDS. DESIGN: This is a secondary analysis of the 2016-2017 PARDS incidence and epidemiology (PARDIE) study, a prospective observational, cross-sectional study of children with PARDS. SETTING: Dataset of 145 PICUs across 27 countries. PATIENTS: During 10 nonconsecutive weeks (from May 2016 to June 2017), data about immunocompromising conditions (ICCs, defined as malignancy, congenital/acquired immunodeficiency, posttransplantation, or diseases requiring immunosuppression) were collected. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Of 708 subjects, 105 (14.8%) had ICC. Before the development of I-PARDS, those with ICC were more likely to be hospitalized (70% vs. 35%, p < 0.001), have more at-risk for PARDS ( p = 0.046), and spent more hours at-risk (20 [interquartile range, IQR: 8-46] vs. 11 [IQR: 4-33], [ p = 0.002]). Noninvasive ventilation (NIV) use was more common in those with ICC ( p < 0.001). Of those diagnosed with PARDS on NIV ( n = 161), children with ICC were more likely to be subsequently intubated ( n = 28/40 [70%] vs n = 53/121 [44%], p = 0.004). Severe PARDS was more common (32% vs 23%, p < 0.001) in I-PARDS. Oxygenation indices were higher at diagnosis and had less improvement over the first 3 days of PARDS ( p < 0.001). Children with I-PARDS had greater nonpulmonary organ dysfunction. Adjusting for Pediatric Risk of Mortality IV and oxygenation index, children with I-PARDS had a higher severity of illness-adjusted PICU mortality (adjusted hazard ratio: 3.0 [95% CI, 1.9-4.7] p < 0.001) and were less likely to be extubated alive within 28 days (subdistribution hazard ratio: 0.47 [95% CI, 0.31-0.71] p < 0.001). CONCLUSIONS: I-PARDS is a unique subtype of PARDS associated with hospitalization before diagnosis and increased: time at-risk for PARDS, NIV use, hypoxia, nonpulmonary organ dysfunction, and mortality. The opportunity for early detection and intervention seems to exist. Dedicated study in these patients is imperative to determine if targeted interventions will benefit these unique patients with the ultimate goal of improving outcomes.


Assuntos
Insuficiência de Múltiplos Órgãos , Síndrome do Desconforto Respiratório , Criança , Humanos , Estudos Prospectivos , Incidência , Estudos Transversais , Respiração Artificial/efeitos adversos
5.
Genes Dev ; 30(14): 1645-57, 2016 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-27474442

RESUMO

Repair of DNA double-strand breaks (DSBs) must be properly orchestrated in diverse chromatin regions to maintain genome stability. The choice between two main DSB repair pathways, nonhomologous end-joining (NHEJ) and homologous recombination (HR), is regulated by the cell cycle as well as chromatin context.Pericentromeric heterochromatin forms a distinct nuclear domain that is enriched for repetitive DNA sequences that pose significant challenges for genome stability. Heterochromatic DSBs display specialized temporal and spatial dynamics that differ from euchromatic DSBs. Although HR is thought to be the main pathway used to repair heterochromatic DSBs, direct tests of this hypothesis are lacking. Here, we developed an in vivo single DSB system for both heterochromatic and euchromatic loci in Drosophila melanogaster Live imaging of single DSBs in larval imaginal discs recapitulates the spatio-temporal dynamics observed for irradiation (IR)-induced breaks in cell culture. Importantly, live imaging and sequence analysis of repair products reveal that DSBs in euchromatin and heterochromatin are repaired with similar kinetics, employ both NHEJ and HR, and can use homologous chromosomes as an HR template. This direct analysis reveals important insights into heterochromatin DSB repair in animal tissues and provides a foundation for further explorations of repair mechanisms in different chromatin domains.


Assuntos
Quebras de DNA de Cadeia Dupla , Reparo do DNA/fisiologia , Drosophila melanogaster/genética , Eucromatina/genética , Heterocromatina/genética , Animais , Técnicas Citológicas , Drosophila melanogaster/citologia , Recombinação Homóloga , Larva
6.
J Biol Chem ; 298(5): 101806, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35271851

RESUMO

Grass pea (Lathyrus sativus L.) is a grain legume commonly grown in Asia and Africa for food and forage. It is a highly nutritious and robust crop, capable of surviving both droughts and floods. However, it produces a neurotoxic compound, ß-N-oxalyl-L-α,ß-diaminopropionic acid (ß-ODAP), which can cause a severe neurological disorder when consumed as a primary diet component. While the catalytic activity associated with ß-ODAP formation was demonstrated more than 50 years ago, the enzyme responsible for this activity has not been identified. Here, we report on the identity, activity, 3D structure, and phylogenesis of this enzyme-ß-ODAP synthase (BOS). We show that BOS belongs to the benzylalcohol O-acetyltransferase, anthocyanin O-hydroxycinnamoyltransferase, anthranilate N-hydroxycinnamoyl/benzoyltransferase, deacetylvindoline 4-O-acetyltransferase superfamily of acyltransferases and is structurally similar to hydroxycinnamoyl transferase. Using molecular docking, we propose a mechanism for its catalytic activity, and using heterologous expression in tobacco leaves (Nicotiana benthamiana), we demonstrate that expression of BOS in the presence of its substrates is sufficient for ß-ODAP production in vivo. The identification of BOS may pave the way toward engineering ß-ODAP-free grass pea cultivars, which are safe for human and animal consumption.


Assuntos
Diamino Aminoácidos , Lathyrus/enzimologia , Neurotoxinas , Acetiltransferases , Diamino Aminoácidos/metabolismo , Simulação de Acoplamento Molecular
7.
Pediatr Res ; 93(5): 1354-1360, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-35933485

RESUMO

BACKGROUND: The functional acute kidney injury (AKI) diagnostic tests serum creatinine (SCr) and urine output are imprecise and make management challenging. Combining tubular injury biomarkers with functional markers reveal AKI phenotypes that may facilitate personalized care. However, when and in whom to obtain injury biomarkers remains unclear. METHODS: This was a prospective, observational study of patients admitted to a pediatric intensive care unit (PICU). Using the Renal Angina Index (RAI), subjects were screened for the presence (RAI+) or absence (RAI-) of renal angina 12 h post-admission and assigned an AKI phenotype using urinary NGAL (NGAL+: ≥150 ng/ml) and SCr (SCr+: ≥KDIGO Stage 1). Outcomes for each AKI phenotype were assessed and compared by RAI status. RESULTS: In all, 200/247 (81%) subjects were RAI+. RAI+ subjects who were NGAL+ had higher risk of Day 3 AKI, renal replacement therapy use, and mortality and fewer ventilator- and PICU-free days, compared to NGAL-, irrespective of Day 0 SCr. Similar findings were not demonstrated in RAI- subjects, though NGAL+/SCr+ was associated with fewer ventilator- and PICU-free days compared to NGAL-/SCr+. CONCLUSIONS: NGAL- and SCr-based AKI phenotypes provide improved prognostic information in children with renal angina (RAI+) and/or with SCr elevation. These populations may be appropriate for targeted biomarker testing. IMPACT: New consensus recommendations encourage the integration of kidney tubular injury biomarkers such as urinary NGAL with serum creatinine for diagnosis and staging of acute kidney injury; however, no structured testing framework exists guiding when to test and in whom. Urinary NGAL- and serum creatinine-based acute kidney injury phenotypes increase diagnostic precision in critically ill children experiencing renal angina (RAI+) or serum creatinine-defined acute kidney injury. These data provide preliminary evidence for a proposed framework for directed urinary NGAL assessment in the pediatric intensive care unit.


Assuntos
Injúria Renal Aguda , Criança , Humanos , Lipocalina-2/urina , Estudos Prospectivos , Creatinina , Injúria Renal Aguda/terapia , Biomarcadores , Fenótipo
8.
Anim Biotechnol ; 34(4): 1030-1039, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34904511

RESUMO

Bovine lymphocyte antigen (BoLA) DRB3 locus in healthy and mastitis affected cattle has been genotyped by a polymerase chain reaction and restriction fragment length polymorphisms (PCR-RLFP) using RsaI restriction enzyme, followed by sequencing. In 130 farm animals, 25 BoLA DRB3 alleles have been detected by PCR-RFLP. Three distinct allelic patterns significantly associated with mastitis in Karan Fries crossbred and Sahiwal indicus cattle have been identified, whereas, four other allelic patterns were significantly high in frequency among healthy animals. Sequencing of RFLP genotypes revealed 25 and 47 alleles among healthy Sahiwal and Karan Fries, respectively, while 17 and 38 patterns observed in mastitis affected Sahiwal and Karan Fries animals, respectively. From Tajima's D-test of neutrality, it was concluded that alleles associated with mastitis were expanding in the population, whereas those of healthy were under contraction. Phylogenetic analysis carried out to delineate the evolutionary relationship of the farm and field animals at DRB3 locus, differentiating allelic patterns into six different clusters. Among the phylogenetic lineages, five patterns DRB3*028:01, DRB3*011:03, DRB3*031:01, DRB3*001:01 and DRB3*043:01, were previously reported, whereas one novel allelic variant was observed in indicus and crossbred cattle. This information will help in further exploring the association between BoLA-DRB3 genetic diversity and disease resistance in distinct cattle breeds, important in designing breeding strategies for increasing the distribution of favorable alleles.


Assuntos
Doenças dos Bovinos , Mastite , Feminino , Bovinos/genética , Animais , Frequência do Gene/genética , Antígenos de Histocompatibilidade Classe II/genética , Alelos , Filogenia , Genótipo , Mastite/genética , Doenças dos Bovinos/genética
9.
Sex Health ; 20(5): 390-402, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37423606

RESUMO

BACKGROUND: The first mpox case was reported in May 2022 in Australia. Most cases have been diagnosed in men who have sex with men (MSM). This study aimed to examine community understanding of mpox, attitudes towards vaccination, and potential changes in sexual practices surrounding the mpox outbreak among MSM and transgender people in Victoria, Australia. METHODS: Participants were recruited from sexual health clinics and communities in Victoria, Australia, in August-October 2022. Participants were asked about their understanding and knowledge of mpox, vaccination uptake and intentions to change sexual practices. Univariable and multivariable logistic regression was performed to examine the factors associated with mpox vaccine uptake. RESULTS: Most participants (97.8%, 525/537) had heard about mpox and 10.5% (55/525) knew someone who had had mpox. Of the 12 mpox knowledge questions, the median score of correct answers was 10 (IQR=8-11) out of a maximum of 12. More than a third (36.6%, 191/522) had been vaccinated against mpox. MSM who had a good knowledge of mpox had the highest odds of receiving mpox vaccine compared with those who had poor knowledge (aOR=4.05; 95% CI: 1.54-10.61). To prevent mpox, half reported they would reduce having sex with casual partners, stop having chemsex (used drugs for the purpose of sex), stop attending sex-on-premises-venues, and stop having group sex. A quarter reported they would increase condom use for anal sex. CONCLUSIONS: One-third of high-risk participants and a substantial proportion of participants intended to reduce or stop certain practices, which may explain the large reduction in mpox cases.

10.
Blood ; 135(13): 1049-1057, 2020 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-31932840

RESUMO

Overactivated complement is a high-risk feature in hematopoietic stem cell transplant (HSCT) recipients with transplant-associated thrombotic microangiopathy (TA-TMA), and untreated patients have dismal outcomes. We present our experience with 64 pediatric HSCT recipients who had high-risk TA-TMA (hrTA-TMA) and multiorgan injury treated with the complement blocker eculizumab. We demonstrate significant improvement to 66% in 1-year post-HSCT survival in treated patients from our previously reported untreated cohort with same hrTA-TMA features that had 1-year post-HSCT survival of 16.7%. Responding patients benefited from a brief but intensive course of eculizumab using pharmacokinetic/pharmacodynamic-guided dosing, requiring a median of 11 doses of eculizumab (interquartile range [IQR] 7-20). Treatment was discontinued because TA-TMA resolved at a median of 66 days (IQR 41-110). Subjects with higher complement activation measured by elevated blood sC5b-9 at the start of treatment were less likely to respond (odds ratio, 0.15; P = .0014) and required more doses of eculizumab (r = 0.43; P = .0004). Patients with intestinal bleeding had the fastest eculizumab clearance, required the highest number of eculizumab doses (20 vs 9; P = .0015), and had lower 1-year survival (44% vs 78%; P = .01). Over 70% of survivors had proteinuria on long-term follow-up. The best glomerular filtration rate (GFR) recovery in survivors was a median 20% lower (IQR, 7.3%-40.3%) than their pre-HSCT GFR. In summary, complement blockade with eculizumab is an effective therapeutic strategy for hrTA-TMA, but some patients with severe disease lacked a complete response, prompting us to propose early intervention and search for additional targetable endothelial injury pathways.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Inativadores do Complemento/uso terapêutico , Proteínas do Sistema Complemento/imunologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Microangiopatias Trombóticas/tratamento farmacológico , Microangiopatias Trombóticas/etiologia , Adolescente , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/efeitos adversos , Criança , Pré-Escolar , Inativadores do Complemento/administração & dosagem , Inativadores do Complemento/efeitos adversos , Suscetibilidade a Doenças , Feminino , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Incidência , Masculino , Medição de Risco , Fatores de Risco , Sepse/epidemiologia , Sepse/etiologia , Microangiopatias Trombóticas/diagnóstico , Resultado do Tratamento
11.
Nanotechnology ; 34(7)2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36179653

RESUMO

Glioblastoma (GBM), the deadliest brain cancer, presents a multitude of challenges to the development of new therapies. The standard of care has only changed marginally in the past 17 years, and few new chemotherapies have emerged to supplant or effectively combine with temozolomide. Concurrently, new technologies and techniques are being investigated to overcome the pharmacokinetic challenges associated with brain delivery, such as the blood brain barrier (BBB), tissue penetration, diffusion, and clearance in order to allow for potent agents to successful engage in tumor killing. Alternative delivery modalities such as focused ultrasound and convection enhanced delivery allow for the local disruption of the BBB, and the latter in particular has shown promise in achieving broad distribution of agents in the brain. Furthermore, the development of polymeric nanocarriers to encapsulate a variety of cargo, including small molecules, proteins, and nucleic acids, have allowed for formulations that protect and control the release of said cargo to extend its half-life. The combination of local delivery and nanocarriers presents an exciting opportunity to address the limitations of current chemotherapies for GBM toward the goal of improving safety and efficacy of treatment. However, much work remains to establish standard criteria for selection and implementation of these modalities before they can be widely implemented in the clinic. Ultimately, engineering principles and nanotechnology have opened the door to a new wave of research that may soon advance the stagnant state of GBM treatment development.


Assuntos
Antineoplásicos , Neoplasias Encefálicas , Glioblastoma , Humanos , Polímeros , Sistemas de Liberação de Medicamentos/métodos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/patologia , Glioblastoma/metabolismo
12.
J Biochem Mol Toxicol ; 36(12): e23215, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36117386

RESUMO

Diabetes-related health issues are increasing day by day in public, and diabetic cardiomyopathy (DCM) is one serious issue among them. There is a lack of proper strategy to control and manage DCM. Here we are attempting a nutraceutical-based approach to protect the heart from DCM. The beneficial effect of cinnamic acid (CiA), was evaluated in an experimental model of diabetes. For this, diabetic model was created by feeding male Wistar rats with a high fat, high fructose diet for 6 months and a single dose of streptozotocin (25 mg/kg bwt). Metformin was used as the positive control. The diabetic rats showed insulin resistance, myocardial injury, and a significant increase of total cholesterol, triglycerides, and LDL. Development of DCM was evident from the increased cardiac mass index, LDH, CKMB, ANP, and CRP levels in the diabetic group. There was a significant increase in the levels of cardiac hypertrophy markers like TGF-ß and ß-MHC in the hearts of diabetic rats revealing DCM. Pro-inflammatory cytokines (TNF-α, IL-6) and lipid peroxides were significantly elevated in the serum of diabetic rats. Histopathology revealed inflammation and necrosis in the heart of diabetic rats confirming DCM. Oral administration of CiA (5 and 10 mg/kg bwt) prevented the development of DCM via its cardioprotective, anti-inflammatory, anti-dyslipidemia potential, and antidiabetic properties. Similarly, metformin (50 mg/kg bwt) has also shown protection against DCM. We conclude from this study that CiA is found to be beneficial against DCM and recommend more detailed preclinical and clinical studies to develop CiA-based nutraceutical against DCM.


Assuntos
Diabetes Mellitus Experimental , Cardiomiopatias Diabéticas , Metformina , Masculino , Ratos , Animais , Cardiomiopatias Diabéticas/tratamento farmacológico , Cardiomiopatias Diabéticas/prevenção & controle , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Ratos Wistar , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Metformina/farmacologia , Metformina/uso terapêutico
13.
Curr Treat Options Oncol ; 23(11): 1566-1589, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36242713

RESUMO

OPINION STATEMENT: Primary malignant central nervous (CNS) tumors are a devastating group of diseases with urgent need for improved treatment options. Surgery, radiation, and cytotoxic chemotherapy remain the primary standard treatment modalities, with molecularly targeted therapies having proven efficacy in only small subsets of cases. Poly(ADP-ribose) polymerase (PARP) inhibitors, which have had immense success in the treatment of extracranial cancers with homologous recombination deficiency (HRD), are emerging as a potential targeted treatment for various CNS tumors. Although few primary CNS tumors display canonical BRCA gene defects, preclinical evidence suggests that PARP inhibitors may benefit certain CNS tumors with functional HRD or elevated replication stress. In addition, other preclinical studies indicate that PARP inhibitors may synergize with standard therapies used for CNS tumors including radiation and alkylating agents and may prevent or overcome drug resistance. Thus far, initial clinical trials with early-generation PARP inhibitors, typically as monotherapy or in the absence of selective biomarkers, have shown limited efficacy. However, the scientific rationale remains promising, and many clinical trials are ongoing, including investigations of more CNS penetrant or more potent inhibitors and of combination therapy with immune checkpoint inhibitors. Early phase trials are also critically focusing on determining active drug CNS penetration and identifying biomarkers of therapy response. In this review, we will discuss the preclinical evidence supporting use of PARP inhibitors in primary CNS tumors and clinical trial results to date, highlighting ongoing trials and future directions in the field that may yield important findings and potentially impact the treatment of these devastating malignancies in the coming years.


Assuntos
Neoplasias do Sistema Nervoso Central , Neoplasias Ovarianas , Feminino , Humanos , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Inibidores de Checkpoint Imunológico , Neoplasias Ovarianas/tratamento farmacológico , Poli(ADP-Ribose) Polimerases , Neoplasias do Sistema Nervoso Central/tratamento farmacológico , Neoplasias do Sistema Nervoso Central/etiologia , Biomarcadores , Alquilantes/uso terapêutico
14.
Pediatr Crit Care Med ; 23(1): 4-12, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34417417

RESUMO

OBJECTIVES: To use improved situation awareness to decrease cardiopulmonary resuscitation events by 25% over 18 months and demonstrate process and outcome sustainability. DESIGN: Structured quality improvement initiative. SETTING: Single-center, 35-bed quaternary-care PICU. PATIENTS: All patients admitted to the PICU from February 1, 2017, to December 31, 2020. INTERVENTIONS: Interventions targeted situation awareness and included bid safety huddles, bedside mitigation signs and huddles, smaller pod-based huddles, and an automated clinical decision support tool to identify high-risk patients. MEASUREMENTS AND MAIN RESULTS: The primary outcome metric, cardiopulmonary resuscitation event rate per 1,000 patient-days, decreased from a baseline of 3.1-1.5 cardiopulmonary resuscitation events per 1,000 patient-days or by 52%. The secondary outcome metric, mortality rate, decreased from a baseline of 6.6 deaths per 1,000 patient-days to 3.6 deaths per 1,000 patient-days. Process metrics included percent of clinical deterioration events predicted, which increased from 40% to 67%, and percent of high-risk patients with shared situation awareness, which increased from 43% to 71%. Balancing metrics included time spent in daily safety huddle, median 0.4 minutes per patient (interquartile range, 0.3-0.5), and a number needed to alert of 16 (95% CI, 14-25). Neither unit acuity as measured by Pediatric Risk of Mortality III scores nor the percent of deaths in patients with do-not-attempt resuscitation orders or electing withdrawal of life-sustaining technologies changed over time. CONCLUSIONS: Interprofessional teams using shared situation awareness may reduce cardiopulmonary resuscitation events and, thereby, improve outcomes.


Assuntos
Reanimação Cardiopulmonar , Parada Cardíaca , Conscientização , Criança , Parada Cardíaca/prevenção & controle , Humanos , Unidades de Terapia Intensiva Pediátrica , Melhoria de Qualidade
15.
Natl Med J India ; 35(3): 147-152, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36461876

RESUMO

Background The Covid-19 pandemic caused a rapidly evolving and confused situation. Health sciences students (HSSs) are not immune to depression, anxiety and stress during such a pandemic. We aimed to assess the relation between depression, anxiety, stress and resilience among undergraduate HSSs during the Covid-19 lockdown. Methods We conducted a cross-sectional, online survey at a rural tertiary healthcare centre in Maharashtra. Data were recorded from study participants on sociodemographic details using the 21-item Depression, Anxiety and Stress Scale (DASS-21) and the Brief Resilience Scale (BRS). Data were analysed using SPSS software version 15.0. Results A total of 381 students participated in the online survey. The prevalence of depression, anxiety and stress were 7.6%, 6.3% and 1.0%, respectively. There was a positive correlation between all three sub-scales of DASS-21. On BRS, 5 (1.3%) participants had high resilience, 216 (56.7%) had normal resilience and 160 (42.0%) had low resilience. Those respondents who had high resilience had lower rates of depression, anxiety and stress on DASS-21 sub-scales. Conclusion A proportion of HSSs had anxiety, depression and stress during the Covid-19 outbreak and lockdown. Respondents with high resilience had less frequent depression, anxiety and stress. In the long run, strengthening resilience of HSSs may be useful.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Estudos Transversais , Pandemias , Depressão/epidemiologia , Atenção Terciária à Saúde , Controle de Doenças Transmissíveis , Índia/epidemiologia , Ansiedade/epidemiologia , Estudantes
16.
Kathmandu Univ Med J (KUMJ) ; 20(78): 171-177, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37017161

RESUMO

Background Hypotension after induction of general anesthesia (GA) is common due to pre-existing hypovolemia and has adverse effects on organ function. Out of several methods to predict post-induction hypotension, nowadays Inferior Vena Cava: Aorta (IVC: Ao) index has been studied with different cut-off values. However, limited studies have been performed in our part of the world. Objective To evaluate the efficacy of pre-induction Inferior Vena Cava: Aorta index with a cutoff value of 1.0 for predicting the occurrence of post-induction hypotension after general anesthesia in the Nepalese population. Method A total of 100 patients of ASA I and II, aged more than 18 years posted for elective surgeries under general anesthesia were enrolled in this cross-sectional, observational study. Ultrasonographic guided Inferior Vena Cava: Aorta index was calculated and based on a cut-off value of 1.0, two groups were formed. Seventy patients in group A with Inferior Vena Cava: Aorta index less than 1.0 and 30 patients in group B with Inferior Vena Cava: Aorta index more than 1.0 were enrolled. Vitals parameters were recorded every minute for five minutes after induction of general anesthesia. Incidence of hypotension was the primary outcome. Statistical analysis was done using student t-test, ANOVA test and Chi-square test. Result Inferior Vena Cava: Aorta index with cut-off value of 1.0 predicted post-induction hypotension with excellent efficacy. Total 65 patients developed post-induction hypotension, out of which 63 patients had Inferior Vena Cava: Aorta index less than 1.0. Conclusion We concluded that pre-induction Inferior Vena Cava: Aorta index with cut-off value of 1.0 have high diagnostic accuracy with high degree of sensitivity and specificity to predict hypotension after induction of general anesthesia.


Assuntos
Hipotensão , Veia Cava Inferior , Humanos , Ultrassonografia/efeitos adversos , Veia Cava Inferior/diagnóstico por imagem , Estudos Transversais , Estudos Prospectivos , Anestesia Geral/efeitos adversos , Hipotensão/etiologia , Aorta/diagnóstico por imagem
17.
Kathmandu Univ Med J (KUMJ) ; 20(78): 243-245, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37017175

RESUMO

Molar pregnancy is a type of abnormal pregnancy that usually presents with amenorrhea, vaginal bleeding and elevated serum ß-hCG levels. We report a rare case of complete hydatidiform mole occurring in a 46-year-old P2L2 lady who presented with a term size uterus and elevated serum ß-hCG level (> 15,00,000 per deciliter, anemia (hemoglobin: 8.1 g/dL), difficulty in breathing and minimal vaginal bleeding. During the course of her evaluation, she had profuse vaginal bleeding, she underwent suction and evacuation, but bleeding was not controlled despite measures to control it. She was given uterotonics and antifibrinolytic agents and uterine artery ligation. But was proceeded with emergency hysterectomy for uncontrolled hemorrhage. The content of suction and evacuation was vesicles with blood clots and histopathology was reported as complete hydatidiform mole. The patient received a total of 4 units of packed red blood cells. She was discharged from hospital on 5th postoperative day and was followed up serial serum ß-hCG level. Therefore, complete mole can present with enlarged uterus, vaginal bleeding and anemia. It is also important to note that intractable bleeding following suction and evacuation not being controlled with uterotonics and antifibrinolytic agents and uterine artery ligation may require hysterectomy to save the patient's life.


Assuntos
Antifibrinolíticos , Mola Hidatiforme , Neoplasias Uterinas , Gravidez , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Uterinas/diagnóstico , Neoplasias Uterinas/cirurgia , Neoplasias Uterinas/patologia , Mola Hidatiforme/diagnóstico , Mola Hidatiforme/cirurgia , Mola Hidatiforme/patologia , Útero/patologia , Hemorragia Uterina/diagnóstico , Hemorragia Uterina/etiologia
18.
J Pharmacol Exp Ther ; 379(3): 343-357, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34556535

RESUMO

The effective treatment of brain tumors is a considerable challenge in part because of the presence of the blood-brain barrier (BBB) that limits drug delivery. Glioblastoma multiforme (GBM) is an aggressive and infiltrative primary brain tumor with an extremely poor prognosis after standard-of-care therapy with surgery, radiotherapy (RT), and chemotherapy. DNA damage response (DDR) pathways play a critical role in DNA repair in cancer cells, and inhibition of these pathways can potentially augment RT and chemotherapy tumor cell toxicity. The ataxia telangiectasia and Rad3-related protein (ATR) kinase is a key regulator of the DDR network and is potently and selectively inhibited by the ATR inhibitor berzosertib. Although in vitro studies demonstrate a synergistic effect of berzosertib in combination with temozolomide, in vivo efficacy studies have yet to recapitulate this observation using intracranial tumor models. In the current study, we demonstrate that delivery of berzosertib to the brain is restricted by efflux at the BBB. Berzosertib has a high binding affinity to brain tissue compared with plasma, thereby leading to low free drug concentrations in the brain. Berzosertib distribution is heterogenous within the tumor, wherein concentrations are substantially lower in normal brain and invasive tumor rim (wherein the BBB is intact) when compared with those in the tumor core (wherein the BBB is leaky). These results demonstrate that high tissue binding and limited and heterogenous brain distribution of berzosertib may be important factors that influence the efficacy of berzosertib therapy in GBM. SIGNIFICANCE STATEMENT: This study examined the brain delivery and efficacy of berzosertib in patient-derived xenograft models of glioblastoma multiforme (GBM). Berzosertib is actively effluxed at the blood-brain barrier and is highly bound to brain tissue, leading to low free drug concentrations in the brain. Berzosertib is heterogeneously distributed into different regions of the brain and tumor and, in this study, was not efficacious in vivo when combined with temozolomide. These factors inform the future clinical utility of berzosertib for GBM.


Assuntos
Encéfalo/metabolismo , Glioblastoma/metabolismo , Isoxazóis/administração & dosagem , Isoxazóis/metabolismo , Pirazinas/administração & dosagem , Pirazinas/metabolismo , Animais , Proteínas Mutadas de Ataxia Telangiectasia/antagonistas & inibidores , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Encéfalo/efeitos dos fármacos , Linhagem Celular Tumoral , Feminino , Glioblastoma/tratamento farmacológico , Células HEK293 , Humanos , Bombas de Infusão , Masculino , Camundongos , Camundongos Knockout , Camundongos Nus , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
19.
Chemistry ; 27(70): 17695-17699, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34697844

RESUMO

Herein we report for the first time, an advanced continuous flow synthesis of the blockbuster Leishmaniasis drug miltefosine from simple starting materials by a sequence involving four steps of chemical transformation including a continuous mechanochemical step. First three reaction steps were performed in simple tubular reactors in a telescopic mode, while in the last step the product precipitated from the 3rd step was used for a continuous mechanochemical synthesis of miltefosine. When compared to a typical batch protocol that takes 15 h, miltefosine was obtained in 58 % overall yield in flow synthesis mode at the laboratory scale in a total residence time 34 min at synthesis rate of 10 g/hr, which is sufficient to treat 4800 patients per day.


Assuntos
Fosforilcolina , Técnicas de Química Sintética , Humanos , Fosforilcolina/análogos & derivados
20.
Pediatr Crit Care Med ; 22(5): e302-e313, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33156209

RESUMO

OBJECTIVES: To serially evaluate health-related quality of life during the first year after community-acquired septic shock in children with preexisting severe developmental disabilities and explore factors associated with health-related quality of life changes in these children. DESIGN: Secondary analysis of the Life after Pediatric Sepsis Evaluation investigation. SETTING: Twelve academic PICU in the United States. PATIENTS: Children greater than or equal to 1 month and less than 18 years old identified by their family caregiver (e.g., parent/guardian) as having severe developmental disability prior to septic shock. INTERVENTIONS: Family caregivers completed the Stein-Jessop Functional Status II-R Short Form as a measure of their child's health-related quality of life at baseline (reflecting preadmission status), day 7, and months 1, 3, 6, and 12 following PICU admission. Stein-Jessop Functional Status II-R Short Form scores were linearly transformed to a 0-100 scale, with higher scores indicating better health-related quality of life. MEASUREMENTS AND MAIN RESULTS: Of 392 Life after Pediatric Sepsis Evaluation participants, 137 were identified by their caregiver as having a severe developmental disability. Sixteen children (11.6%) with severe disability died during the 12 months following septic shock. Among 121 survivors, Stein-Jessop Functional Status II-R Short Form scores declined from preadmission baseline to day 7 (70.7 ± 16.1 vs 55.6 ± 19.2; p < 0.001). Stein-Jessop Functional Status II-R Short Form scores remained below baseline through month 12 (59.1 ± 21.0, p < 0.001 vs baseline). After adjusting for baseline Stein-Jessop Functional Status II-R Short Form, the caregiver being a single parent/guardian was associated with lower month 3 Stein-Jessop Functional Status II-R Short Form scores (p = 0.041). No other baseline child or caregiver characteristic, or critical illness-related factors were significantly associated with month 3 Stein-Jessop Functional Status II-R Short Form scores. CONCLUSIONS: Health-related quality of life among children with severe developmental disability remains, on average, below baseline during the first year following community-acquired septic shock. Children with severe disability and septic shock that are in single parent families are at increased risk. Clinical awareness of the potential for decline in health-related quality of life among disabled children is essential to prevent this adverse outcome from being missed.


Assuntos
Sepse , Choque Séptico , Adolescente , Cuidadores , Criança , Deficiências do Desenvolvimento , Humanos , Qualidade de Vida , Choque Séptico/complicações , Choque Séptico/terapia
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