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1.
Opt Lett ; 49(10): 2545-2548, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748101

RESUMO

We demonstrate the transfer of a cesium frequency standard steered to UTC(NIST) over 20 km of dark telecom optical fiber. Our dissemination scheme uses an active stabilization technique with a phase-locked voltage-controlled oscillator. Out-of-loop characterization of the optical fiber link performance is done with dual-fiber and single-fiber transfer schemes. We observe a fractional frequency instability of 1.5 × 10-12 and 2 × 10-15 at averaging intervals of 1 s and 105 s, respectively, for the link. Both schemes are sufficient to transfer the cesium clock reference without degrading the signal, with nearly an order of magnitude lower fractional frequency instability than the cesium clocks over all time scales. The simplicity of the two-fiber technique may be useful in future long-distance applications where higher stability requirements are not paramount, as it avoids technical complications involved with the single-fiber scheme.

2.
medRxiv ; 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38712176

RESUMO

Background: Recent data have demonstrated that in locally advanced rectal cancer (LARC), a total neoadjuvant therapy (TNT) approach improves compliance with chemotherapy and increases rates of tumor response compared to neoadjuvant chemoradiation (CRT) alone. They further indicate that the optimal sequencing of TNT involves consolidation (rather than induction) chemotherapy to optimize complete response rates. Data, largely from retrospective studies, have also shown that patients with clinical complete response (cCR) after neoadjuvant therapy may be managed safely with the watch and wait approach (WW) instead of preemptive total mesorectal resection (TME). However, the optimal consolidation chemotherapy regimen to achieve cCR has not been established, and a randomized clinical trial has not robustly evaluated cCR as a primary endpoint. Collaborating with a multidisciplinary oncology team and patient groups, we designed this NCI-sponsored study of chemotherapy intensification to address these issues and to drive up cCR rates, to provide opportunity for organ preservation, improve quality of life for patients and improve survival outcomes. Methods: In this NCI-sponsored multi-group randomized, seamless phase II/III trial (1:1), up to 760 patients with LARC, T4N0, any T with node positive disease (any T, N+) or T3N0 requiring abdominoperineal resection or coloanal anastomosis and distal margin within 12 cm of anal verge will be enrolled. Stratification factors include tumor stage (T4 vs T1-3), nodal stage (N+ vs N0) and distance from anal verge (0-4; 4-8; 8-12 cm). Patients will be randomized to receive neoadjuvant long course chemoradiation (LCRT) followed by consolidation doublet (mFOLFOX6 or CAPOX) or triplet chemotherapy (mFOLFIRINOX) for 3-4 months. LCRT in both arms involves 4500 cGy in 25 fractions over 5 weeks + 900 cGy boost in 5 fractions with a fluoropyrimidine (capecitabine preferred). Patients will undergo assessment 8-12 (+/- 4) weeks post-TNT completion. The primary endpoint for the phase II portion will compare cCR between treatment arms. A total number of 296 evaluable patients (148 per arm) will provide statistical power of 90.5% to detect an 17% increase in cCR rate, at a one-sided alpha=0.048. The primary endpoint for the phase III portion will compare disease-free survival (DFS) between treatment arms. A total of 285 DFS events will provide 85% power to detect an effect size of hazard ratio 0.70 at a one-sided alpha of 0.025, requiring enrollment of 760 patients (380 per arm). Secondary objectives include time-to event outcomes (overall survival, organ preservation time and time to distant metastasis) and adverse effects. Biospecimens including archival tumor tissue, plasma and buffy coat in EDTA tubes, and serial rectal MRIs will be collected for exploratory correlative research. This study, activated in late 2022, is open across the NCTN and has a current accrual of 312. Support: U10CA180821, U10CA180882, U24 CA196171; https://acknowledgments.alliancefound.org . Discussion: Building off of data from modern day rectal cancer trials and patient input from national advocacy groups, we have designed the current trial studying chemotherapy intensification via a consolidation chemotherapy approach with the intent to enhance cCR and DFS rates, increase organ preservation rates, and improve quality of life for patients with rectal cancer. Trial Registration: Clinicaltrials.gov ID: NCT05610163 ; Support includes U10CA180868 (NRG) and U10CA180888 (SWOG).

3.
Mar Drugs ; 22(4)2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38667760

RESUMO

The inadequate vascularization seen in fast-growing solid tumors gives rise to hypoxic areas, fostering specific changes in gene expression that bolster tumor cell survival and metastasis, ultimately leading to unfavorable clinical prognoses across different cancer types. Hypoxia-inducible factors (HIF-1 and HIF-2) emerge as druggable pivotal players orchestrating tumor metastasis and angiogenesis, thus positioning them as prime targets for cancer treatment. A range of HIF inhibitors, notably natural compounds originating from marine organisms, exhibit encouraging anticancer properties, underscoring their significance as promising therapeutic options. Bioprospection of the marine environment is now a well-settled approach to the discovery and development of anticancer agents that might have their medicinal chemistry developed into clinical candidates. However, despite the massive increase in the number of marine natural products classified as 'anticancer leads,' most of which correspond to general cytotoxic agents, and only a few have been characterized regarding their molecular targets and mechanisms of action. The current review presents a critical analysis of inhibitors of HIF-1 and HIF-2 and hypoxia-selective compounds that have been sourced from marine organisms and that might act as new chemotherapeutic candidates or serve as templates for the development of structurally similar derivatives with improved anticancer efficacy.


Assuntos
Antineoplásicos , Organismos Aquáticos , Produtos Biológicos , Fator 1 Induzível por Hipóxia , Neoplasias , Animais , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Organismos Aquáticos/química , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/antagonistas & inibidores , Produtos Biológicos/farmacologia , Produtos Biológicos/química , Produtos Biológicos/uso terapêutico , Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Transdução de Sinais/efeitos dos fármacos
6.
Ecol Lett ; 26 Suppl 1: S16-S21, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37840027

RESUMO

Studies of eco-evolutionary dynamics have integrated evolution with ecological processes at multiple scales (populations, communities and ecosystems) and with multiple interspecific interactions (antagonistic, mutualistic and competitive). However, evolution has often been conceptualised as a simple process: short-term directional adaptation that increases population growth. Here we argue that diverse other evolutionary processes, well studied in population genetics and evolutionary ecology, should also be considered to explore the full spectrum of feedback between ecological and evolutionary processes. Relevant but underappreciated processes include (1) drift and mutation, (2) disruptive selection causing lineage diversification or speciation reversal and (3) evolution driven by relative fitness differences that may decrease population growth. Because eco-evolutionary dynamics have often been studied by population and community ecologists, it will be important to incorporate a variety of concepts in population genetics and evolutionary ecology to better understand and predict eco-evolutionary dynamics in nature.


Assuntos
Evolução Biológica , Ecossistema , Dinâmica Populacional , Genética Populacional , Crescimento Demográfico
9.
Antibiotics (Basel) ; 12(5)2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37237772

RESUMO

Pest resistance against fungicides is a widespread and increasing problem, with impact on crop production and public health, making the development of new fungicides an urgent need. Chemical analyses of a crude methanol extract (CME) of Guiera senegalensis leaves revealed the presence of sugars, phospholipids, phytosterols, guieranone A, porphyrin-containing compounds, and phenolics. To connect chemical composition with biological effects, solid-phase extraction was used to discard water-soluble compounds with low affinity for the C18 matrix and obtain an ethyl acetate fraction (EAF) that concentrates guieranone A and chlorophylls, and a methanol fraction (MF) dominated by phenolics. While the CME and MF exhibited poor antifungal activity against Aspergillus fumigatus, Fusarium oxysporum and Colletotrichum gloeosporioides, the EAF demonstrated antifungal activity against these filamentous fungi, particularly against C. gloeosporioides. Studies with yeasts revealed that the EAF has strong effectiveness against Saccharomyces cerevisiae, Cryptococcus neoformans and Candida krusei with MICs of 8, 8 and 16 µg/mL, respectively. A combination of in vivo and in vitro studies shows that the EAF can function as a mitochondrial toxin, compromising complexes I and II activities, and as a strong inhibitor of fungal tyrosinase (Ki = 14.40 ± 4.49 µg/mL). Thus, EAF appears to be a promising candidate for the development of new multi-target fungicides.

10.
J Pediatr Surg ; 58(8): 1578-1581, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37221126

RESUMO

BACKGROUND: Hirschsprung-associated enterocolitis (HAEC) is the most common cause of morbidity and mortality amongst patients with Hirschsprung disease (HD); rectal Botulinum toxin (Botox) has been reported a possible prevention strategy. We aimed to evaluate our institution's historic cohort of HD patients, first to determine our incidence of HAEC and second to begin assessing the effect of Botox on HAEC incidence. METHODS: Patients with HD seen at our institution between 2005 and 2019 were reviewed. Incidence of HD and frequencies of HAEC and Botox injections were tallied. Associations between initial Botox treatment or transition zone and HAEC incidence were evaluated. RESULTS: We reviewed 221 patients; 200 were included for analysis. One hundred thirteen (56.5%) patients underwent primary pull-through at a median age of 24 days (IQR 91). Eighty-seven (43.5%) patients with initial ostomy had their intestinal continuity reestablished at a median of 318 days (IQR 595). Ninety-four (49.5%) experienced at least one episode of HAEC and 62 (66%) experienced multiple episodes of HAEC. Nineteen (9.6%) patients had total colonic HD and had an increased total incidence of HAEC compared to patients without total colonic HD (89% vs 44%, p < 0.001). Six (2.9%) patients received Botox injections at the time of pull-through or ostomy takedown; one experienced an episode of HAEC (versus 50.7% of the patients who were confirmed to have not received Botox injections at their surgery, p = 0.102). CONCLUSION: Further prospective study on Botox's effect on Hirschsprung-associated enterocolitis is required and is the next step in our investigation. LEVEL OF EVIDENCE: Level III.


Assuntos
Toxinas Botulínicas Tipo A , Enterocolite , Doença de Hirschsprung , Humanos , Lactente , Estudos Retrospectivos , Estudos Prospectivos , Toxinas Botulínicas Tipo A/uso terapêutico , Doença de Hirschsprung/complicações , Doença de Hirschsprung/cirurgia , Enterocolite/epidemiologia , Enterocolite/etiologia , Enterocolite/cirurgia , Reto , Complicações Pós-Operatórias/epidemiologia
11.
Bioorg Chem ; 138: 106614, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37216893

RESUMO

The inflammatory response is a vital mechanism for repairing damage induced by aberrant health states or external insults; however, persistent activation can be linked to numerous chronic diseases. The nuclear factor kappa ß (NF-κB) inflammatory pathway and its associated mediators have emerged as critical targets for therapeutic interventions aimed at modulating inflammation, necessitating ongoing drug development. Previous studies have reported the inhibitory effect of a hydroethanol extract derived from Parinari excelsa Sabine (Chrysobalanaceae) on tumour necrosis factor-alpha (TNF-α), but the phytoconstituents and mechanisms of action remained elusive. The primary objective of this study was to elucidate the phytochemical composition of P. excelsa stem bark and its role in the mechanisms underpinning its biological activity. Two compounds were detected via HPLC-DAD-ESI(Ion Trap)-MS2 analysis. The predominant compound was isolated and identified as naringenin-8-sulphonate (1), while the identity of the second compound (compound 2) could not be determined. Both compound 1 and the extract were assessed for anti-inflammatory properties using a cell-based inflammation model, in which THP-1-derived macrophages were stimulated with LPS to examine the treatments' effects on various stages of the NF-κB pathway. Compound 1, whose biological activity is reported here for the first time, demonstrated inhibition of NF-κB activity, reduction in interleukin 6 (IL-6), TNF-α, and interleukin 1 beta (IL-1ß) production, as well as a decrease in p65 nuclear translocation in THP-1 cells, thus highlighting the potential role of sulphur substituents in the activity of naringenin (3). To explore the influence of sulphation on the anti-inflammatory properties of naringenin derivatives, we synthesized naringenin-4'-O-sulphate (4) and naringenin-7-O-sulphate (5) and evaluated their anti-inflammatory effects. Naringenin derivatives 4 and 5 did not display potent anti-inflammatory activities; however, compound 4 reduced IL-1ß production, and compound 5 diminished p65 translocation, with both exhibiting the capacity to inhibit TNF-α and IL-6 production. Collectively, the findings demonstrated that the P. excelsa extract was more efficacious than all tested compounds, while providing insights into the role of sulphation in the anti-inflammatory activity of naringenin derivatives.


Assuntos
Chrysobalanaceae , NF-kappa B , Humanos , NF-kappa B/metabolismo , Interleucina-6/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Chrysobalanaceae/metabolismo , Casca de Planta/metabolismo , Anti-Inflamatórios/uso terapêutico , Inflamação/metabolismo , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Lipopolissacarídeos/farmacologia
12.
Gynecol Oncol ; 173: 58-67, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37086524

RESUMO

BACKGROUND: Despite evidence supporting its use, many Enhanced Recovery After Surgery (ERAS) recommendations remain poorly adhered to and barriers to ERAS implementation persist. In this second updated ERAS® Society guideline, a consensus for optimal perioperative care in gynecologic oncology surgery is presented, with a specific emphasis on implementation challenges. METHODS: Based on the gaps identified by clinician stakeholder groups, nine implementation challenge topics were prioritized for review. A database search of publications using Embase and PubMed was performed (2018-2023). Studies on each topic were selected with emphasis on meta-analyses, randomized controlled trials, and large prospective cohort studies. These studies were then reviewed and graded by an international panel according to the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system. RESULTS: All recommendations on ERAS implementation challenge topics are based on best available evidence. The level of evidence for each item is presented accordingly. CONCLUSIONS: The updated evidence base and recommendations for stakeholder derived ERAS implementation challenges in gynecologic oncology are presented by the ERAS® Society in this consensus review.


Assuntos
Recuperação Pós-Cirúrgica Melhorada , Neoplasias dos Genitais Femininos , Feminino , Humanos , Neoplasias dos Genitais Femininos/cirurgia , Estudos Prospectivos , Assistência Perioperatória , Procedimentos Cirúrgicos em Ginecologia
13.
Life (Basel) ; 13(2)2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36836763

RESUMO

The present work aimed to detail the mechanisms elicited by Allophylus africanus P. Beauv. stem bark extract in human stomach cancer cells and to identify the bioactives underlying the cytotoxicity. MTT reduction and LDH leakage assays allowed characterizing the cytotoxic effects in AGS cells, which were further detailed by morphological analysis using phalloidin and Hoechst 33258. Proapoptotic mechanisms were elucidated through a mitochondrial membrane potential assay and by assessing the impact upon the activity of caspase-9 and -3. The extract displayed selective cytotoxicity against AGS cells. The absence of plasma membrane permeabilization, along with apoptotic body formation, suggested that pro-apoptotic effects triggered cell death. Intrinsic apoptosis pathway activation was verified, as mitochondrial membrane potential decrease and activation of caspase-9 and -3 were observed. HPLC-DAD profiling enabled the identification of two apigenin-di-C-glycosides, vicenin-2 (1) and apigenin-6-C-hexoside-8-C-pentoside (3), as well as three mono-C-glycosides-O-glycosylated derivatives, apigenin-7-O-hexoside-8-C-hexoside (2), apigenin-8-C-(2-rhamnosyl)hexoside (4) and apigenin-6-C-(2-rhamnosyl)hexoside (5). Isovitexin-2″-O-rhamnoside (5) is the main constituent, accounting for nearly 40% of the total quantifiable flavonoid content. Our results allowed us to establish the relationship between the presence of vicenin-2 and other apigenin derivatives with the contribution to the cytotoxic effects on the presented AGS cells. Our findings attest the anticancer potential of A. africanus stem bark against gastric adenocarcinoma, calling for studies to develop herbal-based products and/or the use of apigenin derivatives in chemotherapeutic drug development.

15.
J Trauma Acute Care Surg ; 94(3): 455-460, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36397206

RESUMO

BACKGROUND: The Western Trauma Association (WTA) has undertaken publication of best practice clinical practice guidelines on multiple trauma topics. These guidelines are based on scientific evidence, case reports, and best practices per expert opinion. Some of the topics covered by this consensus group do not have the ability to have randomized controlled studies completed because of complexity, ethical issues, financial considerations, or scarcity of experience and cases. Blunt pancreatic trauma falls under one of these clinically complex and rare scenarios. This algorithm is the result of an extensive literature review and input from the WTA membership and WTA Algorithm Committee members. METHODS: Multiple evidence-based guideline reviews, case reports, and expert opinion were compiled and reviewed. RESULTS: The algorithm is attached with detailed explanation of each step, supported by data if available. CONCLUSION: Blunt pancreatic trauma is rare and presents many treatment challenges.


Assuntos
Traumatismos Abdominais , Traumatismo Múltiplo , Traumatismos Torácicos , Ferimentos não Penetrantes , Humanos , Algoritmos , Traumatismo Múltiplo/terapia , Pâncreas , Ferimentos não Penetrantes/terapia
16.
Clin Oncol (R Coll Radiol) ; 35(1): e94-e102, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36150980

RESUMO

AIMS: Risk stratification, including nodal assessment, allows for selective de-intensification of adjuvant radiotherapy in stage II endometrial cancer. Patterns of treatment and clinical outcomes, including the use of reduced volume 'mini-pelvis' radiotherapy fields, were evaluated in a population-based study. MATERIALS AND METHODS: All patients diagnosed with pathological stage II endometrial cancer between 2000 and 2014, and received adjuvant radiotherapy in a regional healthcare jurisdiction were reviewed. Registry data were supplemented by a comprehensive review of patient demographics, disease characteristics and treatment details. The Charlson Comorbidity Score was calculated. Survival and recurrence data were analysed. RESULTS: In total, 264 patients met the inclusion criteria. Most patients had endometrioid histology (83%); 41% of patients had International Federation of Gynecologists and Obstetricians grade 1 disease. Half (49%) had surgical nodal evaluation; 11% received chemotherapy. Most patients (59%) were treated with full pelvic radiotherapy fields ± brachytherapy. Seventeen per cent of patients received mini-pelvis radiotherapy ± brachytherapy, whereas 24% received brachytherapy alone. Five-year recurrence-free survival was 87% for the entire cohort, with no significant difference by adjuvant radiotherapy approach. Only one patient receiving mini-pelvis radiotherapy ± brachytherapy recurred in the pelvis but outside of the mini-pelvis field. Recorded late toxicity rates were highest for full pelvis radiotherapy + brachytherapy. CONCLUSION: Risk stratification in a real-world setting allowed for selective de-intensification of adjuvant radiation with equivalent outcomes for stage II endometrial cancer. Mini-pelvis radiotherapy combined with brachytherapy is effective in highly selected patients, with the potential to decrease toxicity without compromising local control. Brachytherapy should be considered in low-risk stage II patients.


Assuntos
Braquiterapia , Neoplasias do Endométrio , Feminino , Humanos , Radioterapia Adjuvante , Estudos Retrospectivos , Neoplasias do Endométrio/patologia , Estadiamento de Neoplasias , Histerectomia , Recidiva Local de Neoplasia/patologia
18.
Front Pharmacol ; 14: 1310439, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38371914

RESUMO

Introduction: Despite the increasing number of essential oils being reported on their potential therapeutic effects, some remain relatively unknown on their biological properties. That is the case of the essential oils obtained from copaiba (Copaifera officinalis L.), wintergreen (Gaultheria fragrantissima Wall.), everlasting (Helichrysum italicum (Roth) G.Don) and clove (Syzygium aromaticum (L.) Merr. & L.M.Perry), commonly labelled as being useful on the amelioration of conditions with an inflammatory background. Methods: To further broaden the current knowledge on the four essential oils, commercially available samples were approached on their effects upon a series of mediators that are involved on the inflammatory and oxidative response, both through in vitro cell-free and cell-based assays (5-lipoxygenase activity, lipid peroxidation, free radical and nitric oxide radical scavenging properties or tyrosinase inhibition). Results: The four oils proved to be active at some of the concentrations tested in most of the performed assays. Significant differences were found between the essential oils, S. aromaticum proving to tbe the most active, followed by G. fragrantissima against 5-lipoxygenase (5-LOX) and linoleic acid peroxidation, proving their potential use as antioxidants and anti-inflammatory agents. In fact, the IC50 value of S. aromaticum in the 5-LOX assay was 62.30 µg mL-1. Besides S. aromaticum efficiently scavenged superoxide radicals generated by xanthine/xanthine oxidase, displaying an IC50 value of 135.26 µg mL-1. The essential oil obtained from H. italicum exhibited a significant decrease in the nitric oxide levels on BV-2 cells, showing its potential as a cytoprotective agent against toxic damage. Copaiba oil ranked first as the most potent tyrosinase inhibitor, exhibiting an IC50 98.22 µg mL-1. Conclusion: More studies are needed to describe the essential oils properties, but these results confirm the potential of these essential oils as anti-inflammatory and antioxidant agents.

19.
Gynecol Oncol Rep ; 44: 101119, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36568896

RESUMO

•Somatic yolk sac tumor differentiation associated with malignant neoplasms is uncommon and associated with poor outcome.•In the gynecologic tract, somatic yolk sac differentiation most often arises in postmenopausal patients.•Somatic yolk sac differentiation shares driver mutations with and likely differentiates from the corresponding carcinoma.•This is the first report of somatic yolk sac differentiation in the gynecologic tract from a non-epithelial malignancy.

20.
Peptides ; 157: 170865, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36038014

RESUMO

The gut microbiota presents essential functions in the immune response. The gut epithelium acts as a protective barrier and, therefore, can produce several antimicrobial peptides (AMPs) that can act against pathogenic microorganisms, including bacteria. Several factors cause a disturbance in gut microbiota, including the exacerbated and erroneous use of antibiotics. Antibiotic therapy has been closely related to bacterial resistance and is also correlated with undesired side-effects to the host, including the eradication of commensal bacteria. Consequently, this results in gut microbiota imbalance and inflammatory bowel diseases (IBD) development. In this context, AMPs in the gut epithelium play a restructuring role for gut microbiota. Some naturally occurring AMPs are selective for pathogenic bacteria, thus preserving the health microbiota. Therefore, AMPs produced by the host's epithelial cells represent effective molecules in treating gut bacterial infections. Bearing this in mind, this review focused on describing the importance of the host's AMPs in gut microbiota modulation and their role as anti-infective agents against pathogenic bacteria.


Assuntos
Anti-Infecciosos , Infecções Bacterianas , Microbioma Gastrointestinal , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Peptídeos Antimicrobianos , Bactérias , Humanos
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