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1.
J Dent Res ; : 220345241262949, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39101558

RESUMO

Endodontic access preparation is one of the initial steps in root canal treatments and can be hindered by the obliteration of pulp canals and formation of tertiary dentin. Until now, methods for direct intraoperative visualization of the 3-dimensional anatomy of teeth have been missing. Here, we evaluate the use of shortwave infrared radiation (SWIR) for navigation during stepwise access preparation. Nine teeth (3 anteriors, 3 premolars, and 3 molars) were explanted en bloc with intact periodontium including alveolar bone and mucosa from the upper or lower jaw of human body donors. Analysis was performed at baseline as well as at preparation depths of 5 mm, 7 mm, and 9 mm, respectively. For reflection, SWIR was used at a wavelength of 1,550 nm from the occlusal direction, whereas for transillumination, SWIR was passed through each sample at the marginal gingiva from the buccal as well as oral side at a wavelength of 1,300 nm. Pulpal structures could be identified as darker areas approximately 2 mm before reaching the pulp chamber using SWIR transillumination, although they were indistinguishable under normal circumstances. Furcation areas in molars appeared with higher intensity than areas with canals. The location of pulpal structures was confirmed by superimposition of segmented micro-computed tomography (µCT) images. By radiomic analysis, significant differences between pulpal and parapulpal areas could be detected in image features. With hierarchical cluster analysis, both segments could be confirmed and associated with specific clusters. The local thickness of µCTs was calculated and correlated with SWIR transillumination images, by which a linear dependency of thickness and intensity could be demonstrated. Lastly, by in silico simulations of light propagation, dentin tubules were shown to be a crucial factor for understanding the visibility of the pulp. In conclusion, SWIR transillumination may allow direct clinical live navigation during endodontic access preparation.

2.
EMBO Rep ; 25(9): 3896-3924, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39048751

RESUMO

The Bcl-2 family controls apoptosis by direct interactions of pro- and anti-apoptotic proteins. The principle mechanism is binding of the BH3 domain of pro-apoptotic proteins to the hydrophobic groove of anti-apoptotic siblings, which is therapeutically exploited by approved BH3-mimetic anti-cancer drugs. Evidence suggests that also the transmembrane domain (TMD) of Bcl-2 proteins can mediate Bcl-2 interactions. We developed a highly-specific split luciferase assay enabling the analysis of TMD interactions of pore-forming apoptosis effectors BAX, BAK, and BOK with anti-apoptotic Bcl-2 proteins in living cells. We confirm homotypic interaction of the BAX-TMD, but also newly identify interaction of the TMD of anti-apoptotic BCL-2 with the TMD of BOK, a peculiar pro-apoptotic Bcl-2 protein. BOK-TMD and BCL-2-TMD interact at the endoplasmic reticulum. Molecular dynamics simulations confirm dynamic BOK-TMD and BCL-2-TMD dimers and stable heterotetramers. Mutation of BCL-2-TMD at predicted key residues abolishes interaction with BOK-TMD. Also, inhibition of BOK-induced apoptosis by BCL-2 depends specifically on their TMDs. Thus, TMDs of Bcl-2 proteins are a relevant interaction interface for apoptosis regulation and provide a novel potential drug target.


Assuntos
Apoptose , Ligação Proteica , Domínios Proteicos , Proteínas Proto-Oncogênicas c-bcl-2 , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/química , Humanos , Proteína X Associada a bcl-2/metabolismo , Proteína X Associada a bcl-2/química , Proteína X Associada a bcl-2/genética , Simulação de Dinâmica Molecular , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas/química , Proteínas Proto-Oncogênicas/genética , Retículo Endoplasmático/metabolismo , Proteína Killer-Antagonista Homóloga a bcl-2/metabolismo , Proteína Killer-Antagonista Homóloga a bcl-2/genética , Proteína Killer-Antagonista Homóloga a bcl-2/química , Domínios e Motivos de Interação entre Proteínas , Multimerização Proteica
3.
Rev. chil. obstet. ginecol. (En línea) ; 89(3): 182-188, jun. 2024. tab
Artigo em Espanhol | LILACS | ID: biblio-1569784

RESUMO

El sangrado uterino anormal tiene una etiología variable, que va desde causas estructurales hasta causas funcionales, que se describen clásicamente en el acrónimo PALM-COEIN. No obstante, hay una pobre sensibilización de este síntoma como un marcador de enfermedades graves. En esta revisión se describe la relación de la hemorragia uterina anormal como síntoma clave o de presentación de malignidad hematológica, así como la posible relación con la hemofilia adquirida secundaria a neoplasia hematológica como causal del evento hemostático. Se realizó búsqueda en la literatura, con la mayoría de los artículos obtenidos de Medline, 24 de los cuales cumplieron con los objetivos para resolver la pregunta de investigación. Se encontraron diferentes malignidades hematológicas asociadas a sangrado uterino anormal, de las cuales la hemofilia adquirida y la trombocitopenia como potenciales causales de esta; la mayor correlación fue con leucemia, seguido de linfomas, y en menor cuantía la asociación con mieloma múltiple.


Abnormal uterine bleeding has a variable etiology, ranging from structural to functional causes, classically described by the acronym PALM-COEIN. However, there is poor awareness of this symptom as a marker of serious disease; in this review, we describe the relationship of abnormal uterine bleeding as a key symptom or debut of hematologic malignancy, as well as its possible relationship to acquired hemophilia secondary to hematologic neoplasia as causative of the hemostatic event. A literature search was performed, with most of the articles obtained from Medline, 24 of which met the objectives to solve the research question. Different hematological malignancies associated with abnormal uterine bleeding were found, of which acquired hemophilia and thrombocytopenia were found as potential causes; the highest correlation was with leukemia, followed by lymphomas, and to a lesser extent the association with multiple myeloma.


Assuntos
Humanos , Feminino , Leucemia/complicações , Neoplasias Hematológicas , Neoplasias Hematológicas/complicações , Trombocitopenia/etiologia , Hemorragia Uterina/etiologia , Leucemia/diagnóstico , Hemofilia A
4.
AJP Rep ; 14(2): e129-e132, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38707262

RESUMO

Objective Acute and massive blood loss is fortunately a rare occurrence in perinatal/neonatal practice. When it occurs, typical transfusion paradigms utilize sequential administration of blood components. However, an alternative approach, transfusing type O whole blood with low anti-A and anti-B titers, (LTOWB) has recently been approved and utilized in trauma surgery. Study Design Retrospective analysis of all perinatal patients who have received LTOWB after acute massive hemorrhage at the Intermountain Medical Center. Results LTOWB was the initial transfusion product we used to resuscitate/treat 25 women with acute and massive postpartum hemorrhage and five infants with acute hemorrhage in the first hours/days after birth. We encountered no problems obtaining or transfusing this product and we recognized no adverse effects of this treatment. Conclusion Transfusing LTOWB to perinatal patients after acute blood loss is feasible and appears at least as safe a serial component transfusion. Its use has subsequently been expanded to multiple hospitals in our region as first-line transfusion treatment for acute perinatal hemorrhage. Key Points Low-titer type O whole blood (LTOWB) was our initial transfusion product for 30 perinatal patients with acute hemorrhage. Twenty-five of these were obstetrical patients and five were neonatal patients. We encountered no problems with, or adverse effects from LTOWB in any of these patients. LTOWB transfusions to women were ten days since donor draw (interquartile range, 8-13) and to neonates was six days (5-8).

5.
JBMR Plus ; 8(5): ziae032, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38577522

RESUMO

Skeletal fluorosis is rare and occurs secondary to chronic high amounts of fluoride consumption, manifesting as diffuse osteosclerosis, skeletal pain, connective tissue calcification, and increased fracture risk. Methoxyflurane is a volatile, fluorinated hydrocarbon-inhaled analgesic, and the maximum recommended dose is 15 mL (99.9 % w/w) per wk. A rodent study found increased skeletal fluoride after methoxyflurane exposure. However, skeletal fluorosis secondary to methoxyflurane use in humans has rarely been reported. We present the case of a 47-yr-old female with diffuse osteosclerosis secondary to fluorosis from methoxyflurane use for chronic pain, presenting with 3 yr of generalized bony pain and multiple fragility fractures. Lumbar spine BMD was elevated. CT and radiographs demonstrated new-onset marked diffuse osteosclerosis, with calcification of interosseous membranes and ligaments, and a bone scan demonstrated a grossly increased uptake throughout the skeleton. Biochemistry revealed an elevated alkaline phosphatase and bone turnover markers, mild secondary hyperparathyroidism with vitamin D deficiency, and mild renal impairment. Zoledronic acid, prescribed for presumed Paget's disease, severely exacerbated bony pain. Urinary fluoride was elevated (7.3 mg/L; reference range < 3.0 mg/L) and the patient revealed using methoxyflurane 9 mL per wk for 8 yr for chronic pain. A decalcified bone biopsy revealed haphazardly arranged cement lines and osteocytes lacunae and canaliculi, which was consistent with an osteosclerotic process. Focal subtle basophilic stippling around osteocyte lacunae was suggestive of fluorosis. Although fluorosis is not a histological diagnosis, the presence of compatible histology features was supportive of the diagnosis in this case with clinical-radiological-pathological correlation. Skeletal fluorosis should be considered as a cause of acquired diffuse osteosclerosis. Methoxyflurane should not be recommended for chronic pain. The risk of repeated low-dose exposure to fluoride from methoxyflurane use as analgesia may be greater than expected, and the maximum recommended dose for methoxyflurane may require re-evaluation to minimize skeletal complications. Abbreviated abstract: Skeletal fluorosis is rare and occurs secondary to chronic high amounts of fluoride consumption, manifesting as diffuse osteosclerosis, skeletal pain, connective tissue calcification, and increased fracture risk. We present the case of a 47-yr-old female with skeletal fluorosis secondary to long-term methoxyflurane for chronic pain. The risk of repeated low-dose exposure to fluoride from methoxyflurane use for analgesia may be greater than expected, and the maximum recommended dose for methoxyflurane may require re-evaluation to minimize skeletal complications.

6.
Cell Death Dis ; 15(4): 290, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38658567

RESUMO

High-grade serous ovarian cancer (HGSOC) represents the most common and lethal subtype of ovarian cancer. Despite initial response to platinum-based standard therapy, patients commonly suffer from relapse that likely originates from drug-tolerant persister (DTP) cells. We generated isogenic clones of treatment-naïve and cisplatin-tolerant persister HGSOC cells. In addition, single-cell RNA sequencing of barcoded cells was performed in a xenograft model with HGSOC cell lines after platinum-based therapy. Published single-cell RNA-sequencing data from neo-adjuvant and non-treated HGSOC patients and patient data from TCGA were analyzed. DTP-derived cells exhibited morphological alterations and upregulation of epithelial-mesenchymal transition (EMT) markers. An aggressive subpopulation of DTP-derived cells showed high expression of the stress marker ATF3. Knockdown of ATF3 enhanced the sensitivity of aggressive DTP-derived cells to cisplatin-induced cell death, implying a role for ATF3 stress response in promoting a drug tolerant persister cell state. Furthermore, single cell lineage tracing to detect transcriptional changes in a HGSOC cell line-derived xenograft relapse model showed that cells derived from relapsed solid tumors express increased levels of EMT and multiple endoplasmic reticulum (ER) stress markers, including ATF3. Single cell RNA sequencing of epithelial cells from four HGSOC patients also identified a small cell population resembling DTP cells in all samples. Moreover, analysis of TCGA data from 259 HGSOC patients revealed a significant progression-free survival advantage for patients with low expression of the ATF3-associated partial EMT genes. These findings suggest that increased ATF3 expression together with partial EMT promote the development of aggressive DTP, and thereby relapse in HGSOC patients.


Assuntos
Fator 3 Ativador da Transcrição , Cisplatino , Resistencia a Medicamentos Antineoplásicos , Transição Epitelial-Mesenquimal , Neoplasias Ovarianas , Humanos , Fator 3 Ativador da Transcrição/metabolismo , Fator 3 Ativador da Transcrição/genética , Feminino , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Transição Epitelial-Mesenquimal/genética , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/metabolismo , Animais , Camundongos , Ensaios Antitumorais Modelo de Xenoenxerto , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos
7.
Pharmacol Res Perspect ; 12(3): e1198, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38635290

RESUMO

Individual sirolimus whole blood concentrations are highly variable, critically influenced by the concomitant use of cytochrome P450 (CYP) 3A inducers or inhibitors, and also modulated by food. Therapeutic drug monitoring is therefore recommended, especially at treatment start or in circumstances that can influence sirolimus exposure. In this case report, we highlight the challenge of achieving therapeutic sirolimus concentrations and present pragmatic solutions with regimen adaptions, pharmacokinetic enhancement (use of a drug­drug interaction), concentration monitoring, and subsequent modeling of population pharmacokinetics to support treatment decisions. In a 69-year-old female patient with allogeneic hematopoietic stem cell transplantation, sirolimus concentrations were stable until she developed cerebral toxoplasmosis with tonic­clonic seizures. During treatment of this acute infection, sirolimus concentrations dropped to subtherapeutic levels and remained largely unaffected by dose increases. [Correction added on 4 May 2024, after first online publication: The word "tacrolimus concentrations" has been changed to "sirolimus concentrations" in the preceding sentence.] Only the simultaneous administration of the CYP3A4 inhibitor fluconazole and a shortening of the sirolimus dosing intervals to a (non-approved) twice-daily administration led to successful control of the concentrations, which ultimately even made a dose reduction possible. This intervention resulted in an increase of sirolimus mean trough concentration to 5.85 ng/mL, i.e., into the desired target range. Additionally, a higher ratio of sirolimus trough levels/daily dose from 26.9 to 109 ng/mL/mg/kg/day was achieved with the initiation of fluconazole. Thus, this case report describes the use of clinical pharmacological concepts and pharmacokinetic modeling to optimize treatment strategies in an individual patient. This strategy could be generalized to other CYP inhibitors and other treatment regimens.


Assuntos
Fluconazol , Tacrolimo , Feminino , Humanos , Idoso , Cognição
8.
Biomed Pharmacother ; 173: 116450, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38503239

RESUMO

Cisplatin not only targets DNA but also RNA. However, it is largely unknown whether platinated RNA (Pt-RNA) causes apoptosis and thus contributes to the cytotoxic effects of cisplatin. Consequently, cellular RNA was isolated from HepG2 and LS180 cells, exposed to cisplatin, and the resulting Pt-RNA (20 ng Pt/µg RNA) was transfected into these cancer cell lines or used to treat an apoptosis reporter Caenorhabditis elegans (C. elegans) strain (MD701, expressing CED-1::GFP). Cellular and molecular effects of Pt-RNA were evaluated by luminogenic caspase 3/7 assays, PCR array analysis, and fluorescence microscopy-based quantification of apoptosis in C. elegans gonads. Assuming RNA cross-linking (pseudo double-stranded RNA), the contribution of the Toll-like receptor 3 (TLR3, a sensor of double-stranded RNA) to apoptosis induction in cancer cell lines was investigated by pharmacological TLR3 inhibition and overexpression. In contrast to controls, Pt-RNA significantly enhanced apoptosis in C. elegans (2-fold) and in the cancer cell lines (2-fold to 4-fold). TLR3 overexpression significantly enhanced the pro-apoptotic effects of Pt-RNA in HepG2 cells. TLR3 inhibition reduced the pro-apoptotic effects of Pt-RNA and cisplatin, but not of paclitaxel (off-target control). Gene expression analysis showed that Pt-RNA (but not RNA) significantly enhanced the mRNA levels of nuclear factor kappa B subunit 2 and interleukin-8 in HepG2 cells, suggesting that Pt-RNA is a damage-associated molecular pattern that additionally causes pro-inflammatory responses. Together, this data suggests that not only DNA but also cellular RNA is a functionally relevant target of cisplatin, leading to pro-apoptotic and immunogenic effects.


Assuntos
Cisplatino , Neoplasias , Animais , Cisplatino/farmacologia , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Receptor 3 Toll-Like/genética , Receptor 3 Toll-Like/metabolismo , RNA de Cadeia Dupla/genética , RNA de Cadeia Dupla/farmacologia , Apoptose , Linhagem Celular Tumoral , DNA , Neoplasias/tratamento farmacológico , Neoplasias/genética
9.
Br J Clin Pharmacol ; 90(1): 344-349, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37815301

RESUMO

Short bowel syndrome (SBS) following extensive intestinal resection is often characterized by impaired absorption of orally administered drugs, including tyrosine kinase inhibitors (TKI). We report the case of a patient with EGFR-mutated non-small cell lung carcinoma treated with 80 mg/day of the TKI osimertinib who achieved partial response of the tumour, but was subsequently subjected to a double-barrelled jejunostomy due to ileus. Due to the development of SBS after the bypass surgery, plasma concentrations of osimertinib were monitored using mass spectrometry. The therapeutic drug monitoring confirmed a malabsorption of osimertinib in the patient (108 ng/mL, which is below the 5th percentile of the expected plasma concentration) and was useful to guide adjustments of TKI dosing in order to achieve adequate blood levels (161 ng/mL after increase of the dose to 120 mg/day) in order to maintain tumour control.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Síndrome do Intestino Curto , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Síndrome do Intestino Curto/tratamento farmacológico , Monitoramento de Medicamentos , Mutação , Receptores ErbB/genética , Inibidores de Proteínas Quinases/farmacologia
10.
J Pediatr ; 266: 113879, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38142044

RESUMO

OBJECTIVE: To test feasibility and safety of administering sildenafil in neonates with neonatal encephalopathy (NE), developing brain injury despite therapeutic hypothermia (TH). STUDY DESIGN: We performed a randomized, double-blind, placebo-controlled phase Ib clinical trial between 2016 and 2019 in neonates with moderate or severe NE, displaying brain injury on day-2 magnetic resonance imaging (MRI) despite TH. Neonates were randomized (2:1) to 7-day sildenafil or placebo (2 mg/kg/dose enterally every 12 hours, 14 doses). Outcomes included feasibility and safety (primary outcomes), pharmacokinetics (secondary), and day-30 neuroimaging and 18-month neurodevelopment assessments (exploratory). RESULTS: Of the 24 enrolled neonates, 8 were randomized to sildenafil and 3 to placebo. A mild decrease in blood pressure was reported in 2 of the 8 neonates after initial dose, but not with subsequent doses. Sildenafil plasma steady-state concentration was rapidly reached, but decreased after TH discontinuation. Twelve percent of neonates (1/8) neonates died in the sildenafil group and 0% (0/3) in the placebo group. Among surviving neonates, partial recovery of injury, fewer cystic lesions, and less brain volume loss on day-30 magnetic resonance imaging were noted in 71% (5/7) of the sildenafil group and in 0% (0/3) of the placebo group. The rate of death or survival to 18 months with severe neurodevelopmental impairment was 57% (4/7) in the sildenafil group and 100% (3/3) in the placebo group. CONCLUSIONS: Sildenafil was safe and well-absorbed in neonates with NE treated with TH. Optimal dosing needs to be established. Evaluation of a larger number of neonates through subsequent phases II and III trials is required to establish efficacy. CLINICAL TRIAL REGISTRATION: ClinicalTrials.govNCT02812433.


Assuntos
Asfixia Neonatal , Lesões Encefálicas , Hipotermia Induzida , Hipóxia-Isquemia Encefálica , Doenças do Recém-Nascido , Recém-Nascido , Humanos , Citrato de Sildenafila/efeitos adversos , Asfixia/complicações , Estudos de Viabilidade , Asfixia Neonatal/terapia , Lesões Encefálicas/complicações , Lesões Encefálicas/tratamento farmacológico , Doenças do Recém-Nascido/terapia , Hipóxia-Isquemia Encefálica/terapia , Hipotermia Induzida/métodos , Método Duplo-Cego
11.
Eur J Drug Metab Pharmacokinet ; 49(1): 101-109, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38114885

RESUMO

BACKGROUND AND OBJECTIVE: Although polypharmacy is a particular challenge in daily rheumatological practice, clinical research on the effects of hydroxychloroquine (HCQ), a commonly used drug for patients with rheumatic diseases, is sparse on cytochrome P450 (CYP)-mediated metabolism. We have shown that pre-treatment with pantoprazole does not alter HCQ absorption in healthy volunteers. In this paper, we report the effects of a single 400 mg dose of HCQ on specific CYP3A and CYP2D6 substrates in healthy volunteers. METHODS: In the trial, participants were randomized into two groups (HCQ plus a 9-day course of pantoprazole, or HCQ only). As a secondary endpoint, the effects of a single oral dose of HCQ on the exposure of the oral microdosed CYP3A probe drug midazolam (30 µg) and the oral microdosed CYP2D6 probe drug yohimbine (50 µg) were studied in 23 healthy volunteers (EudraCT no. 2020-001470-30, registered 31 March 2020). RESULTS: The exposure of the probe drugs after intake of HCQ compared with baseline values was quantified by the partial area under the plasma concentration-time curve 0-6 h after administration (AUC0-6 h) for yohimbine and the partial AUC2-4 h for midazolam. Under HCQ, yohimbine AUC0-6 h was unchanged, independent of CYP2D6 genotypes and pantoprazole exposure. Midazolam AUC2-4 h was 25% higher on the day of HCQ administration than at baseline (p = 0.0007). This significant increase was driven by the pantoprazole subgroup, which showed a 46% elevation of midazolam AUC2-4 h as compared with baseline (p < 0.0001). The ratio of midazolam to 1-OH-midazolam partial AUC2-4 h significantly increased from 3.03 ± 1.59 (baseline) to 3.60 ± 1.56 (HCQ) in the pantoprazole group (p = 0.0026). CONCLUSION: In conclusion, we observed an increased midazolam exposure most likely related to pantoprazole.


Assuntos
Citocromo P-450 CYP3A , Hidroxicloroquina , Humanos , Área Sob a Curva , Citocromo P-450 CYP2D6/genética , Citocromo P-450 CYP2D6/metabolismo , Citocromo P-450 CYP3A/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Interações Medicamentosas , Voluntários Saudáveis , Hidroxicloroquina/farmacologia , Hidroxicloroquina/uso terapêutico , Midazolam , Pantoprazol/farmacologia , Preparações Farmacêuticas , Ioimbina
12.
Pharmaceutics ; 15(12)2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38140086

RESUMO

The calcium-dependent serine endoprotease PACE4 is evaluated as a therapeutic target for prostate cancer. The peptide Ac-[d-Leu]LLLRVK-amba inhibits PACE4 with high affinity and has shown efficacy in preclinical mice xenograft models of prostate cancer. To support in vivo examinations of the potential therapeutic peptide Ac-[d-Leu]LLLRVK-amba, we established a highly sensitive assay for its quantification in mouse whole blood microsamples based on UPLC-MS/MS determination. Ac-[d-Leu]LLLRVK-amba was very labile during sample processing, which was particularly pronounced in plasma. High resolution mass spectrometric investigations of the metabolism/degradation in plasma revealed that no peptide bond hydrolysis generated products were formed, leaving the cause of the observed consumption of the peptide elusive. As a consequence, whole-blood quantification was developed relying on the immediate snap-freezing of blood samples after collection and immediate sample processing after serial thawing to ensure accurate and reliable quantification. The assay was validated according to the applicable recommendations of the FDA and EMA in a range of 10-10,000 ng/mL and applied to determine the pharmacokinetics of Ac-[d-Leu]LLLRVK-amba after intravenous and intraperitoneal administration to mice. Individual pharmacokinetic profiles were assessed using four microsamplings per animal. Intraperitoneal absorption was found to be efficient, demonstrating that this well-manageable route of administration is feasible for preclinical efficacy experiments with Ac-[d-Leu]LLLRVK-amba.

13.
Clin Transl Sci ; 16(12): 2483-2493, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37920921

RESUMO

Expression of CYP3A5 protein is a basal and acquired resistance mechanism of pancreatic ductal adenocarcinoma cells conferring protection against the CYP3A and CYP2C8 substrate paclitaxel through metabolic degradation. Inhibition of CYP3A isozymes restores the cells sensitivity to paclitaxel. The combination of gemcitabine and nab-paclitaxel is an established regimen for the treatment of metastasized or locally advanced inoperable pancreatic cancer. Cobicistat is a CYP3A inhibitor developed for the pharmacoenhancement of protease inhibitors. The addition of cobicistat to gemcitabine and nab-paclitaxel may increase the antitumor effect. We will conduct a phase I dose escalation trial with a classical 3 + 3 design to investigate the safety, tolerability, and pharmacokinetics (PKs) of gemcitabine, nab-paclitaxel, and cobicistat. Although the doses of gemcitabine (1000 mg/m2 ) and cobicistat (150 mg) are fixed, three dose levels of nab-paclitaxel (75, 100, and 125 mg/m2 ) will be explored to account for a potential PK drug interaction. After the dose escalation phase, we will set the recommended dose for expansion (RDE) and treat up to nine patients in an expansion part of the trial. The trial is registered under the following identifiers EudraCT-Nr. 2019-001439-29, drks.de: DRKS00029409, and ct.gov: NCT05494866. Overcoming resistance to paclitaxel by CYP3A5 inhibition may lead to an increased efficacy of the gemcitabine and nab-paclitaxel regimen. Safety, efficacy, PK, and RDE data need to be acquired before investigating this combination in a large-scale clinical study.


Assuntos
Carcinoma Ductal Pancreático , Citostáticos , Neoplasias Pancreáticas , Humanos , Gencitabina , Citocromo P-450 CYP3A , Inibidores do Citocromo P-450 CYP3A , Citostáticos/uso terapêutico , Desoxicitidina/efeitos adversos , Cobicistat , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Paclitaxel/efeitos adversos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/patologia , Ensaios Clínicos Fase I como Assunto
14.
Nutr Cancer ; 75(10): 1900-1910, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37791878

RESUMO

Studies of dietary inflammation potential and risks of colorectal cancer precursors are limited, particularly for sessile serrated lesions (SSLs). This study examines the association using the energy-adjusted dietary inflammatory index (E-DIITM), a measure of anti- and/or pro-inflammatory diet, in a large US colonoscopy-based case-control study of 3246 controls, 1530 adenoma cases, 472 hyperplastic polyp cases, and 180 SSL cases. Odds ratios (ORs) and 95% confidence intervals (CIs) were derived from logistic regression models. Analyses were stratified by participant characteristics, and urinary prostaglandin E2 metabolite (PGE-M) and high-sensitivity plasma C-reactive protein (hs-CRP) levels, inflammation biomarkers. Highest E-DII™ intake was associated with significantly increased risks of colorectal adenomas (OR 1.36, 95% CI 1.11, 1.67), and hyperplastic polyps (OR 1.43, 95% CI 1.06, 1.98), compared with participants consuming the lowest E-DII™ quartile. A similar, but non-significant, increased risk was also observed for SSLs (OR 1.41, 95% CI 0.82, 2.41). The positive association was stronger in females (pinteraction <0.001), normal weight individuals (ptrend 0.01), and in individuals with lower inflammatory biomarkers (ptrend 0.02 and 0.01 for PGE-M and hs-CRP, respectively). A high E-DII™ is associated with colorectal polyp risk, therefore promoting an anti-inflammatory diet may aid in preventing colorectal polyps.


Assuntos
Adenoma , Pólipos Adenomatosos , Pólipos do Colo , Neoplasias Colorretais , Neoplasias Retais , Feminino , Humanos , Pólipos do Colo/patologia , Estudos de Casos e Controles , Proteína C-Reativa/metabolismo , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/etiologia , Neoplasias Colorretais/metabolismo , Adenoma/etiologia , Colonoscopia , Dieta/efeitos adversos , Inflamação , Biomarcadores , Fatores de Risco
15.
J Clin Invest ; 134(5)2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37651202

RESUMO

BACKGROUNDFXLEARN, the first-ever large multisite trial of effects of disease-targeted pharmacotherapy on learning, was designed to explore a paradigm for measuring effects of mechanism-targeted treatment in fragile X syndrome (FXS). In FXLEARN, the effects of metabotropic glutamate receptor type 5 (mGluR5) negative allosteric modulator (NAM) AFQ056 on language learning were evaluated in 3- to 6-year-old children with FXS, expected to have more learning plasticity than adults, for whom prior trials of mGluR5 NAMs have failed.METHODSAfter a 4-month single-blind placebo lead-in, participants were randomized 1:1 to AFQ056 or placebo, with 2 months of dose optimization to the maximum tolerated dose, then 6 months of treatment during which a language-learning intervention was implemented for both groups. The primary outcome was a centrally scored videotaped communication measure, the Weighted Communication Scale (WCS). Secondary outcomes were objective performance-based and parent-reported cognitive and language measures.RESULTSFXLEARN enrolled 110 participants, randomized 99, and had 91 who completed the placebo-controlled period. Although both groups made language progress and there were no safety issues, the change in WCS score during the placebo-controlled period was not significantly different between the AFQ056 and placebo-treated groups, nor were there any significant between-group differences in change in any secondary measures.CONCLUSIONDespite the large body of evidence supporting use of mGluR5 NAMs in animal models of FXS, this study suggests that this mechanism of action does not translate into benefit for the human FXS population and that better strategies are needed to determine which mechanisms will translate from preclinical models to humans in genetic neurodevelopmental disorders.TRIAL REGISTRATIONClincalTrials.gov NCT02920892.FUNDING SOURCESNeuroNEXT network NIH grants U01NS096767, U24NS107200, U24NS107209, U01NS077323, U24NS107183, U24NS107168, U24NS107128, U24NS107199, U24NS107198, U24NS107166, U10NS077368, U01NS077366, U24NS107205, U01NS077179, and U01NS077352; NIH grant P50HD103526; and Novartis IIT grant AFQ056X2201T for provision of AFQ056.


Assuntos
Fissura Palatina , Síndrome do Cromossomo X Frágil , Indóis , Hipertermia Maligna , Miotonia Congênita , Adulto , Animais , Criança , Humanos , Síndrome do Cromossomo X Frágil/tratamento farmacológico , Método Simples-Cego , Aprendizagem , Idioma
16.
Am Surg ; 89(12): 6121-6126, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37489517

RESUMO

BACKGROUND: Sexual harassment is a known problem in surgical training and a focus of growing attention in recent years. However, the environments where sexual harassment in surgical training most commonly takes place are not yet described. METHODS: An anonymous, voluntary, electronic survey was distributed to surgical trainees, and all programs nationally were invited to participate. RESULTS: Sixteen general surgery training programs elected to participate, and the survey achieved a response rate of 30%. 48.9% of respondents reported experiencing sexual harassment. The most common location for harassment was in the operating room (OR) (74% of harassed respondents). The second most common location for harassment was the wards (67.4% of harassed respondents). In the OR, attendings and nurses were the most common harassers. The most common harassment in the OR was being called a sexist slur or intimate nickname. DISCUSSION: Surgical trainees report that the OR was the most common location for trainee harassment. Given that harassment is most commonly perpetrated by both attendings and nurses, harassment in surgical training may not entirely be due to hierarchies but may also be attributed to a flawed and permissive OR culture. Surgical training programs should vigilantly eliminate the circumstances that permit sexual harassment in the OR.


Assuntos
Internato e Residência , Médicas , Assédio Sexual , Humanos , Salas Cirúrgicas , Inquéritos e Questionários
17.
Cancer Epidemiol Biomarkers Prev ; 32(10): 1294-1301, 2023 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-37436425

RESUMO

BACKGROUND: Socioeconomic status (SES) at birth is associated with breast cancer risk. Whether this association is driven by changes in breast tissue composition (BTC) prior to adulthood remains unclear. METHODS: We used multivariable linear regression models to examine whether SES at birth is associated with BTC in adolescence and adulthood using data from a New York City cohort of daughters (n = 165, 11-20 years) and mothers (n = 160, 29-55 years). We used maternal-reported data on daughters' household income and maternal education at birth, analyzed individually and in combination (SES index). Women also reported their own mothers' education at birth. We used optical spectroscopy to evaluate BTC measures that positively (water content, collagen content, optical index) and negatively (lipid content) correlate with mammographic breast density, a recognized breast cancer risk factor. RESULTS: Being in the highest versus lowest category of the SES index was associated with lower lipid content [ßadjusted (ßadj) = -0.80; 95% confidence interval (CI), -1.30 to -0.31] and higher collagen content (ßadj = 0.54; 95% CI, 0.09-0.99) in adolescence. In women with a body mass index (BMI) <30 kg/m2, higher maternal education at birth (≥ vs. < high school degree) was associated with lower lipid content (ßadj = -0.57; 95% CI, -0.97 to -0.17), higher water content (ßadj = 0.70; 95% CI, 0.26-1.14), and higher optical index (ßadj = 0.53; 95% CI, 0.10-0.95). CONCLUSIONS: This study supports that SES at birth is associated with BTC in adolescence and adulthood, although the latter association may depend on adult BMI. IMPACT: Further research is needed to identify the socially patterned early life factors influencing BTC.


Assuntos
Neoplasias da Mama , Classe Social , Adulto , Recém-Nascido , Humanos , Feminino , Adolescente , Mama , Densidade da Mama , Índice de Massa Corporal , Lipídeos , Fatores Socioeconômicos
18.
ACS Omega ; 8(26): 23695-23705, 2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37426236

RESUMO

Quantitative monitoring of biologically active methylations of guanines in samples exposed to temozolomide (TMZ) would be useful in glioblastoma research for preclinical TMZ experiments, for clinical pharmacology questions regarding appropriate exposure, and ultimately for precision oncology. The known biologically active alkylation of DNA induced by TMZ takes place on O6 position of guanines. However, when developing mass spectrometric (MS) assays, the possible signal overlap of O6-methyl-2'-deoxyguanosine (O6-m2dGO) with other methylated 2'-deoxyguanosine species in DNA and methylated guanosines in RNA must be considered. Liquid chromatography-tandem MS (LC-MS/MS) offers the analytical requirements for such assays in terms of specificity and sensitivity, especially when multiple reaction monitoring (MRM) is available. In preclinical research, cancer cell lines are still the gold standard model for in vitro drug screening. Here, we present the development of ultra-performance LC-MRM-MS assays for the quantification of O6-m2dGO in a TMZ-treated glioblastoma cell line. Furthermore, we propose adapted parameters for method validation relevant to the quantification of drug-induced DNA modifications.

19.
Heliyon ; 9(6): e16954, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37346332

RESUMO

Background and objectives: Medical science needs to further elucidate the role of ultraviolet radiation (UVR), geographic latitude, and the role of vitamin D in the autoimmune disease multiple sclerosis (MS). We separated several papers into categories out of the thousands published and used their conclusions to explore the relationship between UVR and MS. Relevance: MS is increasing in incidence, particularly in women where MS is two to three times that in men and particularly severe in African Americans. Methods: We collected UVR data at our observatory in Central Maine and calculated the average coefficient of variation (CVUVR) for each month for 15 years (2007-2021, inclusive). Results: The month of conception (MOC) is more important than the month of birth (MOB) in explaining how UVR triggers the variable genetic predisposition to MS. We hypothesize that the rapidly increasing CVUVR is important in preventing an increase in the activity of the vitamin D receptor (VDR) from August to December, which then requires a higher intensity of UVR later in life to suppress the immune system, therefore predisposing to more MS. Limitations: One observatory at about 44° latitude. Conclusions: While variation in UVR is important at the MOC if UVR exceeds a threshold (e.g., if the sunspot number equals or is greater than 90, usually at a solar cycle MAX, or at elevations above approximately 3,000 feet above sea level), the MS mitigating vitamin D-VDR mechanism is overwhelmed and the genotoxic effects of higher-intensity UVR promote MS in those with a genetic predisposition. What is new in this research: This paper offers a new concept in MS research.

20.
Front Pharmacol ; 14: 1128547, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37089922

RESUMO

Introduction: Bulevirtide is a first-in-class antiviral drug to treat chronic hepatitis B/D. We investigated the drug-drug interaction potential and pharmacokinetics of high-dose subcutaneous bulevirtide (5 mg twice daily) with organic anion transporting polypeptide 1B1 (OATP1B1) and cytochrome P450 (CYP) 3A4. Methods: This was a single-center, open-label, fixed-sequence drug-drug interaction trial in 19 healthy volunteers. Before and at bulevirtide steady state, participants ingested a single 40 mg dose of pravastatin. A midazolam microdose was applied to quantify CYP3A4 activity. Results: At bulevirtide steady state, pravastatin area under the concentration-time curve (AUC0-∞) increased 1.32-fold (90% CI 1.08-1.61). The 5 mg bulevirtide twice-daily treatment resulted in a mean AUC0-12 of 1210 h*ng/ml (95% CI 1040-1408) and remained essentially unchanged under the influence of pravastatin. CYP3A4 activity did not change to a clinically relevant extent. As expected, total bile acids increased substantially (35-fold) compared to baseline during bulevirtide treatment. All study medication was well tolerated. Discussion: The study demonstrated that high-dose bulevirtide inhibited OATP1B-mediated hepatic uptake of the marker substrate pravastatin but the extent is considered clinically not relevant. Changes in CYP3A4 activity were also not clinically relevant. In conclusion, this study suggests that OATP1B substrate drugs as well as CYP3A4 substrates may safely be used without dose adjustment in patients treated with bulevirtide. However, in patients using high statin doses and where concomitant factors potentially further increase statin exposure, caution may be required when using bulevirtide.

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