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2.
N Engl J Med ; 388(18): 1680-1691, 2023 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-37133586

RESUMO

BACKGROUND: Idiopathic CD4 lymphocytopenia (ICL) is a clinical syndrome that is defined by CD4 lymphopenia of less than 300 cells per cubic millimeter in the absence of any primary or acquired cause of immunodeficiency. Some 30 years after its original identification, ICL has remained a disease of obscure cause, with limited evidence with respect to its prognosis or management, despite diagnostic and therapeutic innovations. METHODS: We evaluated the clinical, genetic, immunologic, and prognostic characteristics of 108 patients who were enrolled during an 11-year period. We performed whole-exome and targeted gene sequencing to identify genetic causes of lymphopenia. We also performed longitudinal linear mixed-model analyses of T-cell count trajectories and evaluated predictors of clinical events, the response to immunization against coronavirus disease 2019 (Covid-19), and mortality. RESULTS: After the exclusion of patients with genetic and acquired causes of CD4 lymphopenia, the study population included 91 patients with ICL during 374 person-years of follow-up. The median CD4+ T-cell count among the patients was 80 cells per cubic millimeter. The most prevalent opportunistic infections were diseases related to human papillomavirus (in 29%), cryptococcosis (in 24%), molluscum contagiosum (in 9%), and nontuberculous mycobacterial diseases (in 5%). A reduced CD4 count (<100 cells per cubic millimeter), as compared with a CD4 count of 101 to 300 cells, was associated with a higher risk of opportunistic infection (odds ratio, 5.3; 95% confidence interval [CI], 2.8 to 10.7) and invasive cancer (odds ratio, 2.1; 95% CI, 1.1 to 4.3) and a lower risk of autoimmunity (odds ratio, 0.5; 95% CI, 0.2 to 0.9). The risk of death was similar to that in the age- and sex-adjusted general population, but the prevalence of cancer was higher. CONCLUSIONS: Among the study patients, ICL continued to be associated with increased susceptibility to viral, encapsulated fungal, and mycobacterial diseases, as well as with a reduced response to novel antigens and an increased risk of cancer. (Funded by the National Institute of Allergy and Infectious Diseases and the National Cancer Institute; ClinicalTrials.gov number, NCT00867269.).


Assuntos
COVID-19 , Síndromes de Imunodeficiência , Linfopenia , Infecções Oportunistas , Doenças da Imunodeficiência Primária , Humanos , COVID-19/complicações , Síndromes de Imunodeficiência/complicações , Linfopenia/etiologia , Linfócitos T CD4-Positivos , Contagem de Linfócito CD4 , Doenças da Imunodeficiência Primária/complicações
3.
Nat Chem Biol ; 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38834893

RESUMO

Toxic small alarmone synthetase (toxSAS) enzymes constitute a family of bacterial effectors present in toxin-antitoxin and secretion systems. toxSASs act through either translation inhibition mediated by pyrophosphorylation of transfer RNA (tRNA) CCA ends or synthesis of the toxic alarmone adenosine pentaphosphate ((pp)pApp) and adenosine triphosphate (ATP) depletion, exemplified by FaRel2 and FaRel, respectively. However, structural bases of toxSAS neutralization are missing. Here we show that the pseudo-Zn2+ finger domain (pZFD) of the ATfaRel2 antitoxin precludes access of ATP to the pyrophosphate donor site of the FaRel2 toxin, without affecting recruitment of the tRNA pyrophosphate acceptor. By contrast, (pp)pApp-producing toxSASs are inhibited by Tis1 antitoxin domains though occlusion of the pyrophosphate acceptor-binding site. Consequently, the auxiliary pZFD of AT2faRel is dispensable for FaRel neutralization. Collectively, our study establishes the general principles of toxSAS inhibition by structured antitoxin domains, with the control strategy directly coupled to toxSAS substrate specificity.

4.
Nat Chem Biol ; 19(3): 334-345, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36470996

RESUMO

Stringent factors orchestrate bacterial cell reprogramming through increasing the level of the alarmones (p)ppGpp. In Beta- and Gammaproteobacteria, SpoT hydrolyzes (p)ppGpp to counteract the synthetase activity of RelA. However, structural information about how SpoT controls the levels of (p)ppGpp is missing. Here we present the crystal structure of the hydrolase-only SpoT from Acinetobacter baumannii and uncover the mechanism of intramolecular regulation of 'long'-stringent factors. In contrast to ribosome-associated Rel/RelA that adopt an elongated structure, SpoT assumes a compact τ-shaped structure in which the regulatory domains wrap around a Core subdomain that controls the conformational state of the enzyme. The Core is key to the specialization of long RelA-SpoT homologs toward either synthesis or hydrolysis: the short and structured Core of SpoT stabilizes the τ-state priming the hydrolase domain for (p)ppGpp hydrolysis, whereas the longer, more dynamic Core domain of RelA destabilizes the τ-state priming the monofunctional RelA for efficient (p)ppGpp synthesis.


Assuntos
Evolução Biológica , Guanosina Pentafosfato , Conformação Molecular , Hidrolases , Catálise , Ligases/metabolismo , Proteínas de Bactérias/genética
5.
Ann Intern Med ; 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39348691

RESUMO

DESCRIPTION: In March 2020, the White House Coronavirus Task Force determined that clinicians in the United States needed expert treatment guidelines to optimally manage patients with COVID-19, a potentially life-threatening disease caused by a new pathogen for which no specific treatments were known to be effective. METHODS: The U.S. Department of Health and Human Services requested that the National Institutes of Health (NIH) take the lead in expeditiously convening a panel of experts to create "living" guidelines that would be widely accessible and capable of frequent updating as important new information became available. RECOMMENDATIONS: The purpose of this article is to expand on the experiences of the NIH COVID-19 Treatment Guidelines Panel (the Panel) over the past 4 years, summarize the Panel's final recommendations for COVID-19, highlight some challenges and unanswered questions about COVID-19 management, and inform future responses to public health emergencies. The Panel was formed in March 2020, and the first iteration of the guidelines was released in April 2020. Now that the public health emergency has ended, the NIH COVID-19 Treatment Guidelines have sunsetted. This role will now fall to professional societies and organizations, such as the American College of Physicians, the Infectious Diseases Society of America, the Pediatric Infectious Diseases Society, and the World Health Organization, all of which have been active in this area.

6.
Physiol Genomics ; 56(5): 397-408, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38497119

RESUMO

Feed efficiency is a trait of interest in pigs as it contributes to lowering the ecological and economical costs of pig production. A divergent genetic selection experiment from a Large White pig population was performed for 10 generations, leading to pig lines with relatively low- (LRFI) and high- (HRFI) residual feed intake (RFI). Feeding behavior and metabolic differences have been previously reported between the two lines. We hypothesized that part of these differences could be related to differential sensing and absorption of nutrients in the proximal intestine. We investigated the duodenum transcriptome and DNA methylation profiles comparing overnight fasting with ad libitum feeding in LRFI and HRFI pigs (n = 24). We identified 1,106 differentially expressed genes between the two lines, notably affecting pathways of the transmembrane transport activity and related to mitosis or chromosome separation. The LRFI line showed a greater transcriptomic response to feed intake than the HRFI line. Feed intake affected genes from both anabolic and catabolic pathways in the pig duodenum, such as rRNA production and autophagy. Several nutrient transporter and tight junction genes were differentially expressed between lines and/or by short-term feed intake. We also identified 409 differentially methylated regions in the duodenum mucosa between the two lines, while this epigenetic mark was less affected by feeding. Our findings highlighted that the genetic selection for feed efficiency in pigs changed the transcriptome profiles of the duodenum, and notably its response to feed intake, suggesting key roles for this proximal gut segment in mechanisms underlying feed efficiency.NEW & NOTEWORTHY The duodenum is a key organ for the hunger/satiety loop and nutrient sensing. We investigated how the duodenum transcriptome and DNA methylation profiles are affected by feed intakes in pigs. We observed thousands of changes in gene expression levels between overnight-fasted and fed pigs in high-feed efficiency pig lines, but almost none in the related low-feed efficiency pig line.


Assuntos
Metilação de DNA , Transcriptoma , Suínos/genética , Animais , Transcriptoma/genética , Metilação de DNA/genética , Ingestão de Alimentos/genética , Perfilação da Expressão Gênica , Duodeno , Ração Animal
7.
Circulation ; 148(22): 1735-1745, 2023 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-37632455

RESUMO

BACKGROUND: Hospitalization is recognized as a sentinel event in the disease trajectory of patients with heart failure (HF), but not all patients experiencing clinical decompensation are ultimately hospitalized. Outpatient intensification of diuretics is common in response to symptoms of worsening HF, yet its prognostic and clinical relevance, specifically for patients with HF with mildly reduced or preserved ejection fraction, is uncertain. METHODS: In this prespecified analysis of the DELIVER trial (Dapagliflozin Evaluation to Improve the Lives of Patients With Preserved Ejection Fraction Heart Failure), we assessed the association between various nonfatal worsening HF events (those requiring hospitalization, urgent outpatient visits requiring intravenous HF therapies, and outpatient oral diuretic intensification) and rates of subsequent mortality. We further examined the treatment effect of dapagliflozin on an expanded composite end point of cardiovascular death, HF hospitalization, urgent HF visit, or outpatient oral diuretic intensification. RESULTS: In DELIVER, 4532 (72%) patients experienced no worsening HF event, whereas 789 (13%) had outpatient oral diuretic intensification, 86 (1%) required an urgent HF visit, 585 (9%) had an HF hospitalization, and 271 (4%) died of cardiovascular causes as a first presentation. Patients with a first presentation manifesting as outpatient oral diuretic intensification experienced rates of subsequent mortality that were higher (10 [8-12] per 100 patient-years) than those without a worsening HF event (4 [3-4] per 100 patient-years) but similar to rates of subsequent death after an urgent HF visit (10 [6-18] per 100 patient-years). Patients with an HF hospitalization as a first presentation of worsening HF had the highest rates of subsequent death (35 [31-40] per 100 patient-years). The addition of outpatient diuretic intensification to the adjudicated DELIVER primary end point (cardiovascular death, HF hospitalization, or urgent HF visit) increased the overall number of patients experiencing an event from 1122 to 1731 (a 54% increase). Dapagliflozin reduced the need for outpatient diuretic intensification alone (hazard ratio, 0.72 [95% CI, 0.64-0.82]) and when analyzed as a part of an expanded composite end point of worsening HF or cardiovascular death (hazard ratio, 0.76 [95% CI, 0.69-0.84]). CONCLUSIONS: In patients with HF with mildly reduced or preserved ejection fraction, worsening HF requiring oral diuretic intensification in ambulatory care was frequent, adversely prognostic, and significantly reduced by dapagliflozin. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03619213.


Assuntos
Insuficiência Cardíaca Diastólica , Insuficiência Cardíaca , Humanos , Volume Sistólico , Pacientes Ambulatoriais , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/tratamento farmacológico , Compostos Benzidrílicos/uso terapêutico , Diuréticos/uso terapêutico , Função Ventricular Esquerda
8.
Curr Issues Mol Biol ; 46(3): 2320-2342, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38534764

RESUMO

Rare ginsenoside compound K (CK) is an intestinal microbial metabolite with a low natural abundance that is primarily produced by physicochemical processing, side chain modification, or metabolic transformation in the gut. Moreover, CK exhibits potent biological activity compared to primary ginsenosides, which has raised concerns in the field of ginseng research and development, as well as ginsenoside-related dietary supplements and natural products. Ginsenosides Rb1, Rb2, and Rc are generally used as a substrate to generate CK via several bioconversion processes. Current research shows that CK has a wide range of pharmacological actions, including boosting osteogenesis, lipid and glucose metabolism, lipid oxidation, insulin resistance, and anti-inflammatory and anti-apoptosis properties. Further research on the bioavailability and toxicology of CK can advance its medicinal application. The purpose of this review is to lay the groundwork for future clinical studies and the development of CK as a therapy for metabolic disorders. Furthermore, the toxicology and pharmacology of CK are investigated as well in this review. The findings indicate that CK primarily modulates signaling pathways associated with AMPK, SIRT1, PPARs, WNTs, and NF-kB. It also demonstrates a positive therapeutic effect of CK on non-alcoholic fatty liver disease (NAFLD), obesity, hyperlipidemia, diabetes, and its complications, as well as osteoporosis. Additionally, the analogues of CK showed more bioavailability, less toxicity, and more efficacy against disease states. Enhancing bioavailability and regulating hazardous variables are crucial for its use in clinical trials.

9.
Curr Issues Mol Biol ; 46(6): 5488-5510, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38921000

RESUMO

The PHLDA (pleckstrin homology-like domain family) gene family is popularly known as a potential biomarker for cancer identification, and members of the PHLDA family have become considered potentially viable targets for cancer treatments. The PHLDA gene family consists of PHLDA1, PHLDA2, and PHLDA3. The predictive significance of PHLDA genes in cancer remains unclear. To determine the role of pleckstrin as a prognostic biomarker in human cancers, we conducted a systematic multiomics investigation. Through various survival analyses, pleckstrin expression was evaluated, and their predictive significance in human tumors was discovered using a variety of online platforms. By analyzing the protein-protein interactions, we also chose a collection of well-known functional protein partners for pleckstrin. Investigations were also carried out on the relationship between pleckstrins and other cancers regarding mutations and copy number alterations. The cumulative impact of pleckstrin and their associated genes on various cancers, Gene Ontology (GO), and pathway analyses were used for their evaluation. Thus, the expression profiles of PHLDA family members and their prognosis in various cancers may be revealed by this study. During this multiomics analysis, we found that among the PHLDA family, PHLDA1 may be a therapeutic target for several cancers, including kidney, colon, and brain cancer, while PHLDA2 can be a therapeutic target for cancers of the colon, esophagus, and pancreas. Additionally, PHLDA3 may be a useful therapeutic target for ovarian, renal, and gastric cancer.

10.
Curr Issues Mol Biol ; 46(4): 3328-3341, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38666938

RESUMO

Kidney cancer has emerged as a major medical problem in recent times. Multiple compounds are used to treat kidney cancer by triggering cancer-causing gene targets. For instance, isoquercitrin (quercetin-3-O-ß-d-glucopyranoside) is frequently present in fruits, vegetables, medicinal herbs, and foods and drinks made from plants. Our previous study predicted using protein-protein interaction (PPI) and molecular docking analysis that the isoquercitrin compound can control kidney cancer and inflammation by triggering potential gene targets of IGF1R, PIK3CA, IL6, and PTGS2. So, the present study is about further in silico and in vitro validation. We performed molecular dynamic (MD) simulation, gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, cytotoxicity assay, and RT-PCR and qRT-PCR validation. According to the MD simulation (250 ns), we found that IGF1R, PIK3CA, and PTGS2, except for IL6 gene targets, show stable binding energy with a stable complex with isoquercitrin. We also performed gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses of the final targets to determine their regulatory functions and signaling pathways. Furthermore, we checked the cytotoxicity effect of isoquercitrin (IQ) and found that 5 µg/mL and 10 µg/mL doses showed higher cell viability in a normal kidney cell line (HEK 293) and also inversely showed an inhibition of cell growth at 35% and 45%, respectively, in the kidney cancer cell line (A498). Lastly, the RT-PCR and qRT-PCR findings showed a significant decrease in PTGS2, PIK3CA, and IGF1R gene expression, except for IL6 expression, following dose-dependent treatments with IQ. Thus, we can conclude that isoquercitrin inhibits the expression of PTGS2, PIK3CA, and IGF1R gene targets, which in turn controls kidney cancer and inflammation.

11.
Am J Physiol Heart Circ Physiol ; 327(1): H118-H130, 2024 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-38758130

RESUMO

One of the initiating events in preeclampsia (PE) is placental ischemia. Rodent models of placental ischemia do not present with vascular endothelial dysfunction, a hallmark of PE. We previously demonstrated a role for leptin in endothelial dysfunction in pregnancy in the absence of placental ischemia. We hypothesized that placental ischemia requires hyperleptinemia and endothelial mineralocorticoid receptor (ECMR) expression to induce PE-associated endothelial dysfunction in pregnant mice. We induced placental ischemia via the reduced uterine perfusion pressure (RUPP) procedure in pregnant ECMR-intact (ECMR+/+) and ECMR deletion (ECMR-/-) mice at gestational day (GD) 13. ECMR+/+ RUPP pregnant mice also received concurrent leptin infusion via miniosmotic pump (0.9 mg/kg/day). RUPP increased blood pressure via radiotelemetry and decreased fetal growth in ECMR+/+ pregnant mice. Both increases in blood pressure and reduced fetal growth were abolished in RUPP ECMR-/- mice. Placental ischemia did not decrease endothelial-dependent relaxation to acetylcholine (ACh) but increased phenylephrine (Phe) contraction in mesenteric arteries of pregnant mice, which was ablated by ECMR deletion. Addition of leptin to RUPP mice significantly reduced ACh relaxation in ECMR+/+ pregnant mice, accompanied by an increase in soluble FMS-like tyrosine kinase-1 (sFlt-1)/placental growth factor (PLGF) ratio. In conclusion, our data indicate that high leptin levels drive endothelial dysfunction in PE and that ECMR is required for clinical characteristics of hypertension and fetal growth restriction in placental ischemia PE. Collectively, we show that both ECMR and leptin play a role to mediate PE.NEW & NOTEWORTHY Leptin is a key feature of preeclampsia that initiates vascular endothelial dysfunction in preeclampsia characterized by placental ischemia. Endothelial mineralocorticoid receptor (ECMR) deletion in placental ischemia protects pregnant mice from elevations in blood pressure and fetal growth restriction in pregnancy. Increases in leptin production mediate the key pathological feature of endothelial dysfunction in preeclampsia in rodents. ECMR activation contributes to the increase in blood pressure and fetal growth restriction in preeclampsia.


Assuntos
Isquemia , Leptina , Placenta , Pré-Eclâmpsia , Receptores de Mineralocorticoides , Animais , Gravidez , Feminino , Leptina/metabolismo , Leptina/sangue , Placenta/metabolismo , Placenta/irrigação sanguínea , Isquemia/fisiopatologia , Isquemia/metabolismo , Isquemia/genética , Receptores de Mineralocorticoides/metabolismo , Receptores de Mineralocorticoides/genética , Pré-Eclâmpsia/metabolismo , Pré-Eclâmpsia/fisiopatologia , Pré-Eclâmpsia/genética , Camundongos Knockout , Pressão Sanguínea , Camundongos Endogâmicos C57BL , Camundongos , Modelos Animais de Doenças , Retardo do Crescimento Fetal/metabolismo , Retardo do Crescimento Fetal/fisiopatologia , Retardo do Crescimento Fetal/genética , Endotélio Vascular/metabolismo , Endotélio Vascular/fisiopatologia , Vasodilatação/efeitos dos fármacos
12.
Am Heart J ; 272: 23-36, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38460754

RESUMO

BACKGROUND: Yearly influenza vaccination is strongly recommended for older adults and patients with chronic diseases including cardiovascular disease (CVD); however, vaccination rates remain suboptimal, particularly among younger patients. Electronic letters incorporating behavioral nudges are highly scalable public health interventions which can potentially increase vaccination, but further research is needed to determine the most effective strategies and to assess effectiveness across different populations. The purpose of NUDGE-FLU-CHRONIC and NUDGE-FLU-2 are to evaluate the effectiveness of electronic nudges delivered via the Danish governmental electronic letter system in increasing influenza vaccination among patients with chronic diseases and older adults, respectively. METHODS: Both trials are designed as pragmatic randomized implementation trials enrolling all Danish citizens in their respective target groups and conducted during the 2023/2024 influenza season. NUDGE-FLU-CHRONIC enrolls patients aged 18-64 years with chronic diseases. NUDGE-FLU-2 builds upon the NUDGE-FLU trial conducted in 2022/2023 and aims to expand the evidence by testing both previously successful and new nudges among adults ≥65 years during a subsequent influenza season. Persons with exemptions from the electronic letter system are excluded from both trials. In both trials, participants are randomized in a 2.45:1:1:1:1:1:1 ratio to either receive no electronic letter (usual care) or to receive one of 6 different behaviorally informed electronic letters. NUDGE-FLU-CHRONIC has randomized 299,881 participants with intervention letters delivered on September 24, 2023, while NUDGE-FLU-2 has randomized 881,373 participants and delivered intervention letters on September 13, 2023. Follow-up is currently ongoing. In both trials, the primary endpoint is receipt of influenza vaccination on or before January 1, 2024, and the secondary endpoint is time to vaccination. Clinical outcomes including respiratory and cardiovascular hospitalizations, all-cause hospitalization, and mortality are included as prespecified exploratory endpoints. Prespecified individual-level pooled analyses will be conducted across NUDGE-FLU, NUDGE-FLU-CHRONIC, and NUDGE-FLU-2. DISCUSSION: NUDGE-FLU-CHRONIC is the first nationwide randomized trial of electronic nudges to increase influenza vaccination conducted among 18-64-year-old high-risk patients with chronic diseases. NUDGE-FLU-2 will provide further evidence on the effectiveness of electronic nudges among older adults ≥65 years. Collectively, the NUDGE-FLU trials will provide an extensive evidence base for future public health communications. TRIAL REGISTRATION: NUDGE-FLU-CHRONIC: Clinicaltrials.gov: NCT06030739, registered September 11, 2023, https://clinicaltrials.gov/study/NCT06030739. NUDGE-FLU-2: Clinicaltrials.gov: NCT06030726, registered September 11, 2023, https://clinicaltrials.gov/study/NCT06030726.


Assuntos
Vacinas contra Influenza , Influenza Humana , Humanos , Influenza Humana/prevenção & controle , Influenza Humana/epidemiologia , Vacinas contra Influenza/administração & dosagem , Doença Crônica , Pessoa de Meia-Idade , Adulto , Idoso , Masculino , Feminino , Adulto Jovem , Dinamarca/epidemiologia , Vacinação/métodos , Vacinação/estatística & dados numéricos , Adolescente
13.
Biol Chem ; 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39241223

RESUMO

Flow cytometry is a versatile tool used for cell sorting, DNA content imaging, and determining various cellular characteristics. With the possibility of high-throughput analyses, it combines convenient labelling techniques to serve rapid, quantitative, and qualitative workflows. The ease of sample preparation and the broad range of applications render flow cytometry a preferred approach for many scientific questions. Yet, we lack practical adaptations to fully harness the quantitative and high-throughput capabilities of most cytometers for many organisms. Here, we present simple and advanced protocols for the analysis of total DNA content, de novo DNA synthesis, and protein association to chromatin in budding yeast and human cells. Upon optimization of experimental conditions and choice of fluorescent dyes, up to four parameters can be measured simultaneously and quantitatively for each cell of a population in a multi-well plate format. Reducing sample numbers, plastic waste, costs per well, and hands-on time without compromising signal quality or single-cell accuracy are the main advantages of the presented protocols. In proof-of-principle experiments, we show that DNA content increase in S-phase correlates with de novo DNA synthesis and can be predicted by the presence of the replicative helicase MCM2-7 on genomic DNA.

14.
IUBMB Life ; 76(8): 468-484, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38440959

RESUMO

Nanotechnology is considered a successful approach for cancer diagnosis and treatment. Preferentially, cancer cell recognition and drug targeting via nano-delivery system include the penetration of anticancer agents into the cell membrane to damage the cancer cell by protein modification, DNA oxidation, or mitochondrial dysfunction. The past research on nano-delivery systems and their target has proven the beneficial achievement in a malignant tumor. Modern perceptions using inventive nanomaterials for cancer management have been offered by a multifunctional platform based on various nano-carriers with the probability of imaging and cancer therapy simultaneously. Emerging nano-delivery systems in cancer therapy still lack knowledge of the biological functions behind the interaction between nanoparticles and cancer cells. Since the potential of engineered nanoparticles addresses the various challenges, limiting the success of cancer therapy subsequently, it is a must to review the molecular targeting of a nano-delivery system to enhance the therapeutic efficacy of cancer. This review focuses on using a nano-delivery system, an imaging system, and encapsulated nanoparticles for cancer therapy.


Assuntos
Antineoplásicos , Nanomedicina , Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Nanomedicina/métodos , Antineoplásicos/uso terapêutico , Antineoplásicos/administração & dosagem , Nanopartículas/química , Sistemas de Liberação de Medicamentos , Animais , Portadores de Fármacos/química
15.
Ann Surg Oncol ; 31(1): 614-621, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37872456

RESUMO

INTRODUCTION: Many patients with mucinous appendiceal adenocarcinoma experience peritoneal recurrence despite complete cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). Prior work has demonstrated that repeat CRS/HIPEC can prolong survival in select patients. We sought to validate these findings using outcomes from a high-volume center. PATIENTS AND METHODS: Patients with mucinous appendiceal adenocarcinoma who underwent CRS/HIPEC at MD Anderson Cancer Center between 2004 and 2021 were stratified by whether they underwent CRS/HIPEC for recurrent disease or as part of initial treatment. Only patients who underwent complete CRS/HIPEC were included. Initial and recurrent groups were compared. RESULTS: Of 437 CRS/HIPECs performed for mucinous appendiceal adenocarcinoma, 50 (11.4%) were for recurrent disease. Patients who underwent CRS/HIPEC for recurrent disease were more often treated with an oxaliplatin or cisplatin perfusion (35%/44% recurrent vs. 4%/1% initial, p < 0.001), had a longer operative time (median 629 min recurrent vs. 511 min initial, p = 0.002), and had a lower median length of stay (10 days repeat vs. 13 days initial, p < 0.001). Thirty-day complication and 90-day mortality rates did not differ between groups. Both cohorts enjoyed comparable recurrence free survival (p = 0.82). Compared with patients with recurrence treated with systemic chemotherapy alone, this select cohort of patients undergoing repeat CRS/HIPEC enjoyed better overall survival (p < 0.001). CONCLUSIONS: In appropriately selected patients with recurrent appendiceal mucinous adenocarcinoma, CRS/HIPEC can provide survival benefit equivalent to primary CRS/HIPEC and that may be superior to that conferred by systemic therapy alone in select patients. These patients should receive care at a high-volume center in the context of a multidisciplinary team.


Assuntos
Adenocarcinoma Mucinoso , Neoplasias do Apêndice , Hipertermia Induzida , Neoplasias Peritoneais , Humanos , Quimioterapia Intraperitoneal Hipertérmica , Procedimentos Cirúrgicos de Citorredução , Terapia Combinada , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Hipertermia Induzida/efeitos adversos , Neoplasias Peritoneais/patologia , Recidiva Local de Neoplasia/patologia , Neoplasias do Apêndice/patologia , Adenocarcinoma Mucinoso/patologia , Estudos Retrospectivos , Taxa de Sobrevida
16.
J Card Fail ; 30(2): 391-398, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37806488

RESUMO

There is waning interest among cardiology trainees in pursuing an Advanced Heart Failure/Transplant Cardiology (AHFTC) fellowship as evidenced by fewer applicants in the National Resident Matching Program match to this specialty. This trend has generated considerable attention across the heart failure community. In response, the Heart Failure Society of America convened the AHFTC Fellowship Task Force with a charge to develop strategies to increase the value proposition of an AHFTC fellowship. Subsequently, the HFSA sponsored the AHFTC Fellowship Consensus Conference April 26-27, 2023. Before the conference, interviews of 44 expert stakeholders diverse across geography, site of practice (traditional academic medical center or other centers), specialty/area of expertise, sex, and stage of career were conducted virtually. Based on these interviews, potential solutions to address the declining interest in AHFTC fellowship were categorized into five themes: (1) alternative training pathways, (2) regulatory and compensation, (3) educational improvements, (4) exposure and marketing for pipeline development, and (5) quality of life and mental health. These themes provided structure to the deliberations of the AHFTC Fellowship Consensus Conference. The recommendations from the Consensus Conference were subsequently presented to the HFSA Board of Directors to inform strategic plans and interventions. The HFSA Board of Directors later reviewed and approved submission of this document. The purpose of this communication is to provide the HF community with an update summarizing the processes used and concepts that emerged from the work of the HFSA AHFTC Fellowship Task Force and Consensus Conference.


Assuntos
Cardiologia , Insuficiência Cardíaca , Humanos , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/cirurgia , Bolsas de Estudo , Qualidade de Vida , Consenso
17.
Microb Pathog ; 196: 106990, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39362288

RESUMO

The rising demand for innovative antimicrobial solutions has shifted focus towards silver nanoparticles (AgNPs), especially those produced through eco-friendly methods. This study introduces a novel approach utilizing actinomycetes strains-Streptomyces albus, Micromonospora maris, and Arthrobacter crystallopoietes-to biosynthesize AgNPs with remarkable antibacterial properties. Through molecular characterization, we identified unique features of these nanoparticles, and computational modeling suggested significant ion-ligand interactions with proteins 6REV and 3K07. Our research highlights the promise of these biogenically synthesized nanoparticles in advancing biomedical applications. Actinomycetes were sourced and screened for their ability to produce metallic nanoparticles, revealing that among 35 samples, only six showed this capability. Notably, Streptomyces albus strain smmdk14 (OR685674), Micromonospora maris strain smmdk13 (OR685672), and Arthrobacter crystallopoietes strain smmdk12 (OR685674) were identified as effective silver nanoparticle producers. The synthesized nanoparticles demonstrated potent antibacterial activity against common pathogens including E. coli, Pseudomonas aeruginosa, Klebsiella spp., Enterococcus faecalis, Staphylococcus aureus, and Acinetobacter spp. The data obtained from color change observation, UV-visible spectrophotometry, Zeta potential, FTIR spectroscopy, and transmission electron microscopy (TEM) characterized AgNPs potentiality. The nanoparticles were spherical, with sizes ranging from 6.46 nm to 24.7 nm. Optimization of production conditions, comparison of antimicrobial effects with antibiotics, evaluation of potential toxicity, and assessment of wound-healing capabilities were also conducted. The biosynthesized AgNPs exhibited superior antibacterial properties compared to traditional antibiotics and significantly accelerated wound healing by approximately 66.4 % in fibroblast cell cultures. Additionally, computational analysis predicted interactions between various metal ions and specific amino acid residues in proteins 6REV and 3K07. Overall, this study demonstrates the successful creation of AgNPs with notable antibacterial and wound-healing properties, underscoring their potential for medical applications.


Assuntos
Actinobacteria , Antibacterianos , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Prata , Prata/farmacologia , Prata/química , Prata/metabolismo , Nanopartículas Metálicas/química , Antibacterianos/farmacologia , Antibacterianos/química , Actinobacteria/metabolismo , Actinobacteria/química , Modelos Moleculares , Bactérias/efeitos dos fármacos , Arthrobacter/efeitos dos fármacos , Arthrobacter/metabolismo , Streptomyces/metabolismo , Streptomyces/química , Espectroscopia de Infravermelho com Transformada de Fourier , Microscopia Eletrônica de Transmissão
18.
Toxicol Appl Pharmacol ; 484: 116880, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38447874

RESUMO

Gastric ulcer (GU) is a serious upper gastrointestinal tract disorder that affects people worldwide. The drugs now available for GU treatment have a high rate of relapses and drug interactions, as well as mild to severe side effects. As a result, new natural therapeutic medications for treating GU with fewer negative side effects are desperately needed. Because of quercetin's (QCT) diverse pharmacological effects and unique structural features, we decided to semi-synthesize new QCT derivatives and test them for antiulcer activity. Docking assays were performed on the synthesized compounds to determine their affinity for TLR-4/MD-2, MyD88/TIR, and NF-κB domains, an important inflammatory pathway involved in GU development and progression. Mice were given oral famotidine (40 mg/kg/day), QCT, QCT pentamethyl (QPM), or QCT pentaacetyl (QPA) (50 mg/kg/day) for 5 days before GU induction by a single intraperitoneal injection of indomethacin (INDO; 18 mg/kg). QPM and QPA have a stronger binding affinity for TLR-4/MD-2, MyD88/TIR and NF-κB domains than QCT. In comparison, they demonstrated the greatest reduction in ulcer score and index, gastric MDA and nitric oxide (NO) contents, MyD88 and NF-κB expressions, and gastric TLR-4 immunostaining. They also enhanced the levels of GSH, CAT, COX-1, and COX-2 in the gastric mucosa, as well as HO-1 and Nrf2 expression, with histological regression in gastric mucosal lesions, with QPA-treated mice demonstrating the best GU healing. QPA is safe against all of the target organs and adverse pathways studied, with good ADME properties. However, further in vitro experiments are necessary to demonstrate the inhibitory effects of QPM and QPA on the protein targets of interest. In addition, preclinical research on its bioavailability and safety is essential before clinical management can be undertaken. Overall, the new QPA derivative could one day serve as the basis for a new class of potential antiulcer drugs.


Assuntos
Indometacina , Úlcera Gástrica , Humanos , Camundongos , Animais , Indometacina/toxicidade , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/tratamento farmacológico , Úlcera Gástrica/patologia , Quercetina/farmacologia , Quercetina/uso terapêutico , Simulação de Acoplamento Molecular , Úlcera/metabolismo , Úlcera/patologia , NF-kappa B/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Receptor 4 Toll-Like/metabolismo , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patologia
19.
Opt Lett ; 49(8): 1933-1936, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38621044

RESUMO

Low phase noise and narrow linewidth lasers are achieved by implementing self-injection locking of a DFB laser on two distinct fiber Fabry-Perot resonators. More than 45 dB improvement of the laser phase or frequency noise is observed when the laser is locked. In both cases, a frequency noise floor below 1 Hz2/Hz is measured. The integrated linewidth of the best of the two lasers is computed to be in the range of 400 Hz and appears to be dominated by vibration noise close to the carrier. The results are then compared with a model based on the retro-injected power and the Q factors ratio between the DFB laser and the resonator. This straightforward model facilitates the extraction of the theoretical performance of these sources close to the carrier, a characteristic still hidden by vibration noise.

20.
Opt Lett ; 49(11): 3214-3217, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824366

RESUMO

We report a theoretical and experimental investigation of fiber Fabry-Perot cavities aimed at enhancing Kerr frequency comb generation. The modulation instability (MI) power threshold is derived from the linear stability analysis of a generalized Lugiato-Lefever equation. By combining this analysis with the concepts of power enhancement factor (PEF) and optimal coupling, we predict the ideal manufacturing parameters of fiber Fabry-Perot (FFP) cavities for the MI Kerr frequency comb generation. Our findings reveal a distinction between the optimal coupling for modulation instability and that of the cold cavity. Consequently, mirror reflectivity must be adjusted to suit the specific application. We verified the predictions of our theory by measuring the MI power threshold as a function of detuning for three different cavities.

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