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1.
J Inflamm (Lond) ; 21(1): 14, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38689261

RESUMEN

BACKGROUND: The DNA-dependent protein kinase (DNA-PK) complex comprises a catalytic (PRKDC) and two requisite DNA-binding (Ku70/Ku80) subunits. The role of the complex in repairing double-stranded DNA breaks (DSBs) is established, but its role in inflammation, as a complex or individual subunits, remains elusive. While only ~ 1% of PRKDC is necessary for DNA repair, we reported that partial inhibition blocks asthma in mice without causing SCID. METHODS: We investigated the central role of PRKDC in inflammation and its potential association with DNA repair. We also elucidated the relationship between inflammatory cytokines (e.g., TNF-α) and PRKDC by analyzing its connections to inflammatory kinases. Human cell lines, primary human endothelial cells, and mouse fibroblasts were used to conduct the in vitro studies. For animal studies, LPS- and oxazolone-induced mouse models of acute lung injury (ALI) and delayed-type hypersensitivity (DHT) were used. Wild-type, PRKDC+/-, or Ku70+/- mice used in this study. RESULTS: A ~ 50% reduction in PRKDC markedly blocked TNF-α-induced expression of inflammatory factors (e.g., ICAM-1/VCAM-1). PRKDC regulates Th1-mediated inflammation, such as DHT and ALI, and its role is highly sensitive to inhibition achieved by gene heterozygosity or pharmacologically. In endothelial or epithelial cells, TNF-α promoted rapid PRKDC phosphorylation in a fashion resembling that induced by, but independent of, DSBs. Ku70 heterozygosity exerted little to no effect on ALI in mice, and whatever effect it had was associated with a specific increase in MCP-1 in the lungs and systemically. While Ku70 knockout blocked VP-16-induced PRKDC phosphorylation, it did not prevent TNF-α - induced phosphorylation of the kinase, suggesting Ku70 dispensability. Immunoprecipitation studies revealed that PRKDC transiently interacts with p38MAPK. Inhibition of p38MAPK blocked TNF-α-induced PRKDC phosphorylation. Direct phosphorylation of PRKDC by p38MAPK was demonstrated using a cell-free system. CONCLUSIONS: This study presents compelling evidence that PRKDC functions independently of the DNA-PK complex, emphasizing its central role in Th1-mediated inflammation. The distinct functionality of PRKDC as an individual enzyme, its remarkable sensitivity to inhibition, and its phosphorylation by p38MAPK offer promising therapeutic opportunities to mitigate inflammation while sparing DNA repair processes. These findings expand our understanding of PRKDC biology and open new avenues for targeted anti-inflammatory interventions.

2.
Antibiotics (Basel) ; 13(3)2024 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-38534701

RESUMEN

Acinetobacter baumannii has been described as a cause of serious community-acquired infections in tropical countries. Currently, its implications when simultaneously identified with other pathogens are not yet adequately understood. A descriptive study was conducted on hospitalized patients with a diagnosis of moderate/severe SARS-CoV-2-induced pneumonia confirmed via real-time RT-PCR. Patients aged > 18 years who were admitted to a specialized COVID-19 treatment center in Peru were selected for enrollment. A. baumannii was detected via the PCR amplification of the blaOXA-51 gene obtained from nasopharyngeal swabs within 48 h of hospitalization. A total of 295 patients with COVID-19 who met the study inclusion criteria were enrolled. A. baumannii was simultaneously identified in 40/295 (13.5%) of COVID-19-hospitalized patients. Demographic data and comorbidities were comparable in both Acinetobacter-positive and -negative subgroups. However, patients identified as being infected with Acinetobacter were more likely to have received outpatient antibiotics prior to hospitalization, had a higher requirement for high-flow nasal cannula and a higher subjective incidence of fatigue, and were more likely to develop Acinetobacter-induced pneumonia during hospitalization. Conclusions: The group in which SARS-CoV-2 and A. baumannii were simultaneously identified had a higher proportion of fatigue, a higher frequency of requiring a high-flow cannula, and a higher proportion of superinfection with the same microorganism during hospitalization.

3.
Int J Mol Sci ; 24(24)2023 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-38139077

RESUMEN

This review presents a comprehensive update of the biopolymer poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), emphasizing its production, properties, and applications. The overall biosynthesis pathway of PHBV is explored in detail, highlighting recent advances in production techniques. The inherent physicochemical properties of PHBV, along with its degradation behavior, are discussed in detail. This review also explores various blends and composites of PHBV, demonstrating their potential for a range of applications. Finally, the versatility of PHBV-based materials in multiple sectors is examined, emphasizing their increasing importance in the field of biodegradable polymers.


Asunto(s)
Poliésteres , Polímeros , Ácido 3-Hidroxibutírico , Poliésteres/química , Ácidos Pentanoicos
4.
Front Immunol ; 14: 1244159, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37901240

RESUMEN

Introduction: Triple-negative breast cancer (TNBC) comprises a heterogeneous group of clinically aggressive tumors with high risk of recurrence and metastasis. Current pharmacological treatment options remain largely limited to chemotherapy. Despite promising results, the efficacy of immunotherapy and chemo-immunotherapy in TNBC remains limited. There is strong evidence supporting the involvement of Notch signaling in TNBC progression. Expression of Notch1 and its ligand Jagged1 correlate with poor prognosis. Notch inhibitors, including g-secretase inhibitors (GSIs), are quite effective in preclinical models of TNBC. However, the success of GSIs in clinical trials has been limited by their intestinal toxicity and potential for adverse immunological effects, since Notch plays key roles in T-cell activation, including CD8 T-cells in tumors. Our overarching goal is to replace GSIs with agents that lack their systemic toxicity and ideally, do not affect tumor immunity. We identified sulindac sulfide (SS), the active metabolite of FDA-approved NSAID sulindac, as a potential candidate to replace GSIs. Methods: We investigated the pharmacological and immunotherapeutic properties of SS in TNBC models in vitro, ex-vivo and in vivo. Results: We confirmed that SS, a known γ-secretase modulator (GSM), inhibits Notch1 cleavage in TNBC cells. SS significantly inhibited mammosphere growth in all human and murine TNBC models tested. In a transplantable mouse TNBC tumor model (C0321), SS had remarkable single-agent anti-tumor activity and eliminated Notch1 protein expression in tumors. Importantly, SS did not inhibit Notch cleavage in T- cells, and the anti-tumor effects of SS were significantly enhanced when combined with a-PD1 immunotherapy in our TNBC organoids and in vivo. Discussion: Our data support further investigation of SS for the treatment of TNBC, in conjunction with chemo- or -chemo-immunotherapy. Repurposing an FDA-approved, safe agent for the treatment of TNBC may be a cost-effective, rapidly deployable therapeutic option for a patient population in need of more effective therapies.


Asunto(s)
Sulindac , Neoplasias de la Mama Triple Negativas , Humanos , Animales , Ratones , Sulindac/farmacología , Sulindac/uso terapéutico , Secretasas de la Proteína Precursora del Amiloide , Neoplasias de la Mama Triple Negativas/metabolismo , Antiinflamatorios no Esteroideos/uso terapéutico , Modelos Animales de Enfermedad
5.
Cancers (Basel) ; 15(15)2023 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-37568775

RESUMEN

BACKGROUND: The efficacy of CB-103 was evaluated in preclinical models of both ER+ and TNBC. Furthermore, the therapeutic efficacy of combining CB-103 with fulvestrant in ER+ BC and paclitaxel in TNBC was determined. METHODS: CB-103 was screened in combination with a panel of anti-neoplastic drugs. We evaluated the anti-tumor activity of CB-103 with fulvestrant in ESR1-mutant (Y537S), endocrine-resistant BC xenografts. In the same model, we examined anti-CSC activity in mammosphere formation assays for CB-103 alone or in combination with fulvestrant or palbociclib. We also evaluated the effect of CB-103 plus paclitaxel on primary tumors and CSC in a GSI-resistant TNBC model HCC1187. Comparisons between groups were performed with a two-sided unpaired Students' t-test. A one-way or two-way ANOVA followed by Tukey's post-analysis was performed to analyze the in vivo efficacy study results. THE RESULTS: CB-103 showed synergism with fulvestrant in ER+ cells and paclitaxel in TNBC cells. CB-103 combined with fulvestrant or paclitaxel potently inhibited mammosphere formation in both models. Combination of CB-103 and fulvestrant significantly reduced tumor volume in an ESR1-mutant, the endocrine-resistant BC model. In a GSI-resistant TNBC model, CB-103 plus paclitaxel significantly delayed tumor growth compared to paclitaxel alone. CONCLUSION: our data indicate that CB-103 is an attractive candidate for clinical investigation in endocrine-resistant, recurrent breast cancers with biomarker-confirmed Notch activity in combination with SERDs and/or CDKis and in TNBCs with biomarker-confirmed Notch activity in combination with taxane-containing chemotherapy regimens.

6.
J Funct Biomater ; 14(7)2023 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-37504844

RESUMEN

Medical gloves, along with masks and gowns, serve as the initial line of defense against potentially infectious microorganisms and hazardous substances in the health sector. During the COVID-19 pandemic, medical gloves played a significant role, as they were widely utilized throughout society in daily activities as a preventive measure. These products demonstrated their value as important personal protection equipment (PPE) and reaffirmed their relevance as infection prevention tools. This review describes the evolution of medical gloves since the discovery of vulcanization by Charles Goodyear in 1839, which fostered the development of this industry. Regarding the current market, a comparison of the main properties, benefits, and drawbacks of the most widespread types of sanitary gloves is presented. The most common gloves are produced from natural rubber (NR), polyisoprene (IR), acrylonitrile butadiene rubber (NBR), polychloroprene (CR), polyethylene (PE), and poly(vinyl chloride) (PVC). Furthermore, the environmental impacts of the conventional natural rubber glove manufacturing process and mitigation strategies, such as bioremediation and rubber recycling, are addressed. In order to create new medical gloves with improved properties, several biopolymers (e.g., poly(vinyl alcohol) and starch) and additives such as biodegradable fillers (e.g., cellulose and chitin), reinforcing fillers (e.g., silica and cellulose nanocrystals), and antimicrobial agents (e.g., biguanides and quaternary ammonium salts) have been evaluated. This paper covers these performance-enhancing materials and describes different innovative prototypes of gloves and coatings designed with them.

7.
Viruses ; 15(3)2023 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-36992464

RESUMEN

The human neurotropic Polyomavirus JCPyV is the widespread opportunistic causative pathogen of the fatal demyelinating disease progressive multifocal leukoencephalopathy; however, it has also been implicated in the oncogenesis of several types of cancers. It causes brain tumors when intracerebrally inoculated into rodents, and genomic sequences of different strains and expression of the viral protein large T-Antigen have been detected in a wide variety of glial brain tumors and CNS lymphomas. Here, we present a case of an AIDS-related multifocal primary CNS lymphoma in which JCPyV genomic sequences of the three regions of JCPyV and expression of T-Antigen were detected by PCR and immunohistochemistry, respectively. No capsid proteins were detected, ruling out active JCPyV replication. Sequencing of the control region revealed that Mad-4 was the strain of JCPyV present in tumor cells. In addition, expression of viral proteins LMP and EBNA-1 from another ubiquitous oncogenic virus, Epstein-Barr, was also detected in the same lymphocytic neoplastic cells, co-localizing with JCPyV T-Antigen, suggesting a potential collaboration between these two viruses in the process of malignant transformation of B-lymphocytes, which are the site of latency and reactivation for both viruses.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida , Neoplasias Encefálicas , Virus JC , Linfoma de Células B Grandes Difuso , Poliomavirus , Humanos , Poliomavirus/genética , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/metabolismo , Virus JC/fisiología , Proteínas Virales/genética , Antígenos Virales de Tumores/genética , Sistema Nervioso Central/metabolismo
8.
Cells ; 12(2)2023 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-36672197

RESUMEN

The novel coronavirus, SARS-CoV-2, rapidly spread worldwide, causing an ongoing global pandemic. While the respiratory system is the most common site of infection, a significant number of reported cases indicate gastrointestinal (GI) involvement. GI symptoms include anorexia, abdominal pain, nausea, vomiting, and diarrhea. Although the mechanisms of GI pathogenesis are still being examined, viral components isolated from stool samples of infected patients suggest a potential fecal-oral transmission route. In addition, viral RNA has been detected in blood samples of infected patients, making hematologic dissemination of the virus a proposed route for GI involvement. Angiotensin-converting enzyme 2 (ACE2) receptors serve as the cellular entry mechanism for the virus, and these receptors are particularly abundant throughout the GI tract, making the intestine, liver, and pancreas potential extrapulmonary sites for infection and reservoirs sites for developing mutations and new variants that contribute to the uncontrolled spread of the disease and resistance to treatments. This transmission mechanism and the dysregulation of the immune system play a significant role in the profound inflammatory and coagulative cascades that contribute to the increased severity and risk of death in several COVID-19 patients. This article reviews various potential mechanisms of gastrointestinal, liver, and pancreatic injury.


Asunto(s)
COVID-19 , Humanos , SARS-CoV-2 , Hígado , Intestinos , Páncreas
9.
Expert Rev Hematol ; 16(3): 213-226, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36563352

RESUMEN

BACKGROUND: Guidelines for congenital coagulopathies recommend that patients record treatment administrations and bleeding episodes to help healthcare professionals monitor the disease. RESEARCH DESIGN AND METHODS: We studied over two years which patient profiles (age, treatment regimen, treatment compliance) were most likely to accept the use of an app to collect this information. We validated the quality of patient-reported data by comparing it with data obtained from hospital electronic records, pharmacy dispensing records and patient interview, collected in an access database used as a reference. Patient and professional opinions were solicited through open-ended interviews. RESULTS: The app was used by 52% of 315 patients studied. Younger patients were the most frequent users. Patients with better treatment compliance used the app more, although data collection was incomplete for most patients. The best rated by patients were the reminders of days of administration and the minimum stock alerts at home. Healthcare professionals rated the app positively. CONCLUSIONS: Healthcare professionals valued the app as useful for managing treatment of congenital coagulopathies. Patients need support and time to use the app and improve the quality of the data entered. Patients who used the app rated it positively. The treatment compliance improved.


Asunto(s)
Trastornos de la Coagulación Sanguínea , Aplicaciones Móviles , Servicios Farmacéuticos , Humanos , Estudios de Seguimiento , Cooperación del Paciente
10.
Eur J Hosp Pharm ; 30(5): 268-272, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-34620687

RESUMEN

OBJECTIVES: Abiraterone and enzalutamide are two oral novel androgen receptor axis-targeted agents approved for the treatment of castration-resistant prostate cancer (mCRPC). Despite the availability of multiple treatments, there is a need to improve the knowledge and management of these drugs in the real-world setting, especially in patient groups under-represented in clinical trials. Our aim was to review the outcome of patients with chemotherapy-naïve mCRPC treated with abiraterone or enzalutamide in routine clinical practice in order to identify factors that are predictive for response. METHODS: This observational retrospective study was performed in a Spanish tertiary hospital and included men with chemotherapy-naïve mCPRC who started treatment with abiraterone or enzalutamide between September 2012 and November 2018. The study end date was 30 October 2020. RESULTS: Ninety patients with mCRPC were included, 57 with abiraterone and 33 with enzalutamide. Median overall survival (OS) was 26.87 months (95% CI 19.68 to 34.05), with no difference found between the two treatment groups. Nine variables were related to increased OS in the univariate analysis: Eastern Cooperative Oncology Group (ECOG) performance status (0-1 vs 2), pain (need of opioids for cancer pain), visceral disease, ≥3 bone lesions, exclusively lymph node metastases, baseline prostate specific antigen (PSA) (<50 vs ≥50 ng/dL and <20 vs ≥20 ng/dL), haemoglobin (<12 vs ≥12 g/dL) and alkaline phosphatase (≤116 vs >116 IU/L). A PSA response >50% was observed in 65 patients (76.5%). In the multivariate analysis, ECOG performance status, pain, visceral disease and alkaline phosphatase provided independent prognostic information. Median OS by Kaplan-Meier analysis was significantly longer for patients with a PSA response (32.1 vs 17.9 months; HR 0.46, 95% CI 0.27 to 0.78; p=0.003). CONCLUSIONS: This study assessed the efficacy of abiraterone and enzalutamide in a real-world setting, including patients under-represented in pivotal studies. Some clinical factors were correlated with improved OS in chemotherapy-naïve men with mCPRC treated with these drugs.


Asunto(s)
Neoplasias de la Próstata Resistentes a la Castración , Masculino , Humanos , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Neoplasias de la Próstata Resistentes a la Castración/patología , Antígeno Prostático Específico/uso terapéutico , Estudios Retrospectivos , Fosfatasa Alcalina/uso terapéutico
11.
12.
Int J Mol Sci ; 23(19)2022 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-36232652

RESUMEN

Great advances in cancer treatment have been undertaken in the last years as a consequence of the development of new antitumoral drugs able to target cancer cells with decreasing side effects and a better understanding of the behavior of neoplastic cells during invasion and metastasis. Specifically, drug delivery systems (DDS) based on the use of hydroxyapatite nanoparticles (HAp NPs) are gaining attention and merit a comprehensive review focused on their potential applications. These are derived from the intrinsic properties of HAp (e.g., biocompatibility and biodegradability), together with the easy functionalization and easy control of porosity, crystallinity and morphology of HAp NPs. The capacity to tailor the properties of DLS based on HAp NPs has well-recognized advantages for the control of both drug loading and release. Furthermore, the functionalization of NPs allows a targeted uptake in tumoral cells while their rapid elimination by the reticuloendothelial system (RES) can be avoided. Advances in HAp NPs involve not only their use as drug nanocarriers but also their employment as nanosystems for magnetic hyperthermia therapy, gene delivery systems, adjuvants for cancer immunotherapy and nanoparticles for cell imaging.


Asunto(s)
Nanopartículas , Neoplasias , Sistemas de Liberación de Medicamentos/métodos , Durapatita/uso terapéutico , Humanos , Nanopartículas/uso terapéutico , Neoplasias/tratamiento farmacológico , Neoplasias/terapia , Porosidad
13.
J Neurosurg Case Lessons ; 4(4): CASE22189, 2022 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-36046269

RESUMEN

BACKGROUND: Primary intracranial rhabdomyosarcoma is an extraordinarily rare malignant tumor, with even fewer presenting with distant metastasis. To date, only five cases, including the one presented here, have been reported to present metastatic activity. OBSERVATIONS: A 12-year-old boy presented with a few days of headache, nausea, vomiting, but no neurological deficit. Brain computed tomography and magnetic resonance imaging demonstrated hydrocephalus and a cystic lesion with left parieto-occipital extension. After resection, pathology reported primary rhabdomyosarcoma, with positive desmin and myogenin on immunohistochemistry. The patient presented with pulmonary metastasis. The patient had an overall survival of 21 months after diagnosis with optimal treatment. LESSONS: Rhabdomyosarcoma is a malignant neoplasm arising from undifferentiated skeletal muscle cells, with morphological, immunohistochemical, ultrastructural, or molecular genetic evidence of primary skeletal muscle differentiation. It presents with a rapidly worsening clinical course and the final outcome is poor. Treatment is widely based on protocols that have been proven to be effective in extracranial versions of these tumors, although repeatedly ineffective. Primary brain rhabdomyosarcoma poses a diagnostic challenge because of its infrequent presentation, grade of undifferentiation and tumor heterogeneity. Immunohistochemical and genetic testing have proven to be useful tools for diagnosis.

14.
PLoS One ; 17(4): e0265820, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35395015

RESUMEN

INTRODUCTION: The rapid expansion of the novel SARS-CoV-2 virus has raised serious public health concerns due to the possibility of misdiagnosis in regions where arboviral diseases are endemic. We performed the first study in northern Peru to describe the detection of SARS-CoV-2 IgM antibodies in febrile patients with a suspected diagnosis of dengue and chikungunya fever. MATERIALS AND METHODS: A consecutive cross-sectional study was performed in febrile patients attending primary healthcare centers from April 2020 through March 2021. Patients enrolled underwent serum sample collection for the molecular and serological detection of DENV and CHIKV. Also, serological detection of IgM antibodies against SARS-CoV-2 was performed. RESULTS: 464 patients were included during the study period, of which (40.51%) were positive for one pathogen, meanwhile (6.90%) presented co-infections between 2 or more pathogens. The majority of patients with monoinfections were positive for SARS-CoV-2 IgM with (73.40%), followed by DENV 18.09% and CHIKV (8.51%). The most frequent co-infection was DENV + SARS-CoV-2 with (65.63%), followed by DENV + CHIKV and DENV + CHIKV + SARS-CoV-2, both with (12.50%). The presence of polyarthralgias in hands (43.75%, p<0.01) and feet (31.25%, p = 0.05) were more frequently reported in patients with CHIKV monoinfection. Also, conjunctivitis was more common in patients positive for SARS-CoV-2 IgM (11.45%, p<0.01). The rest of the symptoms were similar among all the study groups. CONCLUSION: SARS-CoV-2 IgM antibodies were frequently detected in acute sera from febrile patients with a clinical suspicion of arboviral disease. The presence of polyarthralgias in hands and feet may be suggestive of CHIKV infection. These results reaffirm the need to consider SARS-CoV-2 infection as a main differential diagnosis of acute febrile illness in arboviruses endemic areas, as well as to consider co-infections between these pathogens.


Asunto(s)
COVID-19 , Fiebre Chikungunya , Virus Chikungunya , Coinfección , Virus del Dengue , Dengue , Infección por el Virus Zika , Anticuerpos Antivirales , Artralgia , COVID-19/diagnóstico , COVID-19/epidemiología , Fiebre Chikungunya/diagnóstico , Fiebre Chikungunya/epidemiología , Coinfección/diagnóstico , Coinfección/epidemiología , Estudios Transversales , Dengue/diagnóstico , Dengue/epidemiología , Fiebre/diagnóstico , Humanos , Inmunoglobulina M , Perú/epidemiología , SARS-CoV-2 , Infección por el Virus Zika/epidemiología
16.
Int J Mol Sci ; 23(5)2022 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-35269593

RESUMEN

Amorphous molecule-macromolecule mixtures are ubiquitous in polymer technology and are one of the most studied routes for the development of amorphous drug formulations. For these applications it is crucial to understand how the preparation method affects the properties of the mixtures. Here, we employ differential scanning calorimetry and broadband dielectric spectroscopy to investigate dispersions of a small-molecule drug (the Nordazepam anxiolytic) in biodegradable polylactide, both in the form of solvent-cast films and electrospun microfibres. We show that the dispersion of the same small-molecule compound can have opposite (plasticizing or antiplasticizing) effects on the segmental mobility of a biopolymer depending on preparation method, temperature, and polymer enantiomerism. We compare two different chiral forms of the polymer, namely, the enantiomeric pure, semicrystalline L-polymer (PLLA), and a random, fully amorphous copolymer containing both L and D monomers (PDLLA), both of which have lower glass transition temperature (Tg) than the drug. While the drug has a weak antiplasticizing effect on the films, consistent with its higher Tg, we find that it actually acts as a plasticizer for the PLLA microfibres, reducing their Tg by as much as 14 K at 30%-weight drug loading, namely, to a value that is lower than the Tg of fully amorphous films. The structural relaxation time of the samples similarly depends on chemical composition and morphology. Most mixtures displayed a single structural relaxation, as expected for homogeneous samples. In the PLLA microfibres, the presence of crystalline domains increases the structural relaxation time of the amorphous fraction, while the presence of the drug lowers the structural relaxation time of the (partially stretched) chains in the microfibres, increasing chain mobility well above that of the fully amorphous polymer matrix. Even fully amorphous homogeneous mixtures exhibit two distinct Johari-Goldstein relaxation processes, one for each chemical component. Our findings have important implications for the interpretation of the Johari-Goldstein process as well as for the physical stability and mechanical properties of microfibres with small-molecule additives.


Asunto(s)
Plastificantes , Polímeros , Biopolímeros , Rastreo Diferencial de Calorimetría , Temperatura
17.
Gels ; 8(2)2022 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-35200501

RESUMEN

Biocompatible hydrogels with antibacterial properties derived from γ-polyglutamic acid (γ-PGA) were prepared from bulk and electrospun nanofibers. The antibacterial drugs loaded in these hydrogels were triclosan (TCS), chlorhexidine (CHX) and polyhexamethylene biguanide (PHMB); furthermore, bacteriophages were loaded as an alternative antibacterial agent. Continuous and regular γ-PGA nanofibers were successfully obtained by the electrospinning of trifluoroacetic acid solutions in a narrow polymer concentration range and restricted parameter values of flow rate, voltage and needle-collector distance. Hydrogels were successfully obtained by using cystamine as a crosslinking agent following previous published procedures. A closed pore structure was characteristic of bulk hydrogels, whereas an open but structurally consistent structure was found in the electrospun hydrogels. In this case, the morphology of the electrospun nanofibers was drastically modified after the crosslinking reaction, increasing their diameter and surface roughness according to the amount of the added crosslinker. The release of TCS, CHX, PHMB and bacteriophages was evaluated for the different samples, being results dependent on the hydrophobicity of the selected medium and the percentage of the added cystamine. A high efficiency of hydrogels to load bacteriophages and preserve their bactericide activity was demonstrated too.

18.
Int J Mol Sci ; 23(3)2022 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-35163204

RESUMEN

The preparation, characterization, and controlled release of hydroxyapatite (HAp) nanoparticles loaded with streptomycin (STR) was studied. These nanoparticles are highly appropriate for the treatment of bacterial infections and are also promising for the treatment of cancer cells. The analyses involved scanning electron microscopy, dynamic light scattering (DLS) and Z-potential measurements, as well as infrared spectroscopy and X-ray diffraction. Both amorphous (ACP) and crystalline (cHAp) hydroxyapatite nanoparticles were considered since they differ in their release behavior (faster and slower for amorphous and crystalline particles, respectively). The encapsulated nanoparticles were finally incorporated into biodegradable and biocompatible polylactide (PLA) scaffolds. The STR load was carried out following different pathways during the synthesis/precipitation of the nanoparticles (i.e., nucleation steps) and also by simple adsorption once the nanoparticles were formed. The loaded nanoparticles were biocompatible according to the study of the cytotoxicity of extracts using different cell lines. FTIR microspectroscopy was also employed to evaluate the cytotoxic effect on cancer cell lines of nanoparticles internalized by endocytosis. The results were promising when amorphous nanoparticles were employed. The nanoparticles loaded with STR increased their size and changed their superficial negative charge to positive. The nanoparticles' crystallinity decreased, with the consequence that their crystal sizes reduced, when STR was incorporated into their structure. STR maintained its antibacterial activity, although it was reduced during the adsorption into the nanoparticles formed. The STR release was faster from the amorphous ACP nanoparticles and slower from the crystalline cHAp nanoparticles. However, in both cases, the STR release was slower when incorporated in calcium and phosphate during the synthesis. The biocompatibility of these nanoparticles was assayed by two approximations. When extracts from the nanoparticles were evaluated in cultures of cell lines, no cytotoxic damage was observed at concentrations of less than 10 mg/mL. This demonstrated their biocompatibility. Another experiment using FTIR microspectroscopy evaluated the cytotoxic effect of nanoparticles internalized by endocytosis in cancer cells. The results demonstrated slight damage to the biomacromolecules when the cells were treated with ACP nanoparticles. Both ACP and cHAp nanoparticles were efficiently encapsulated in PLA electrospun matrices, providing functionality and bioactive properties.


Asunto(s)
Sistemas de Liberación de Medicamentos/métodos , Nanopartículas/uso terapéutico , Estreptomicina/administración & dosificación , Animales , Antibacterianos/química , Infecciones Bacterianas/tratamiento farmacológico , Células COS , Línea Celular Tumoral , Chlorocebus aethiops , Durapatita/química , Humanos , Nanopartículas/química , Poliésteres/química , Estreptomicina/farmacología , Andamios del Tejido/química , Células Vero
19.
BMC Infect Dis ; 22(1): 96, 2022 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-35090394

RESUMEN

BACKGROUND: At the end of 2019, a novel coronavirus denominated SARS-CoV-2 rapidly spread through the world causing the pandemic coronavirus disease known as COVID-19. The difference in the inflammatory response against SARS-CoV-2 infection among people living at different altitudes is a variable not yet studied. METHODS: A descriptive cross-sectional study was performed in two Peruvian cities at different altitudes for comparison: Lima and Huaraz. Five important proinflammatory cytokines were measured including: IL-6, IL-2, IL-10, IFN-γ and TNF-α using ELISA assays. RESULTS: A total of 35 COVID-19 patients and 10 healthy subjects were recruited from each study site. The mean levels of IL-6 (p < 0.03) and TNF-α (p < 0.01) were significantly different among the study groups. In the case of IL-6, patients from Lima had a mean level of 16.2 pg/ml (healthy) and 48.3 pg/ml (COVID-19), meanwhile, patients from Huaraz had levels of 67.3 pg/ml (healthy) and 97.9 pg/ml (COVID-19). Regarding TNF-α, patients from Lima had a mean level of 25.9 pg/ml (healthy) and 61.6 pg/ml (COVID-19), meanwhile, patients from Huaraz had levels of 89.0 pg/ml (healthy) and 120.6 pg/ml (COVID-19). The levels of IL-2, IL-10 and IFN-γ were not significantly different in the study groups. CONCLUSION: Patients with COVID-19 residing at high-altitude tend to have higher levels of inflammatory cytokines compared to patients living at sea level, particularly IL-6 and TNF-α. A better understanding of the inflammatory response in different populations can contribute to the implementation of therapeutic and preventive approaches. Further studies evaluating more patients, a greater variety of cytokines and their clinical impact are required.


Asunto(s)
Altitud , COVID-19 , Estudios Transversales , Citocinas , Humanos , SARS-CoV-2
20.
Clin Breast Cancer ; 22(2): 103-114, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34903452

RESUMEN

PRECLINICAL STUDIES: have demonstrated a complex cross-talk between Notch and estrogen signaling in ERα-positive breast cancer. Gamma-secretase inhibitors (GSIs) are investigational agents that block the cleavage and activation of Notch receptors. In animal models of endocrine-resistant breast cancer, combinations of tamoxifen and GSIs produce additive or synergistic efficacy, while decreasing the intestinal toxicity of GSIs. However, results of a clinical trial of a GSI-endocrine therapy combination in the metastatic setting have not been published to date, nor had the safety of such combinations been investigated with longer term treatment. We conducted a phase 1b dose escalation trial (NCT01149356) of GSI RO4929097 with exemestane in patients with ERα+, metastatic breast cancer (MBC) STUDY OBJECTIVES: To determine the safety, tolerability and maximum tolerated dose (MTD) or recommended phase 2 dose (RP2D) of RO4929097 when administered in combination with exemestane in patients with estrogen receptor positive metastatic breast cancer RESULTS: We enrolled 15 patients with MBC. Of 14 evaluable patients, one had a partial response, 6 had stable disease and 7 progressive disease. Twenty % of patients had stable disease for ≥ 6 months. Common toxicities included nausea (73.3%), anorexia (60%), hyperglycemia (53.3%), hypophosphatemia (46.7%), fatigue (66.7%) and cough (33.0%). Grade 3 toxicities were uncommon, and included hypophosphatemia (13%) and rash (6.3%). Rash was the only DLT observed at 140 mg/d. Results suggest a possible recommended phase 2 dose of 90 mg/d. Ten patients with evaluable archival tissue showed expression of PKCα, which correlated with expression of Notch4. Mammospheres from a PKCα-expressing, endocrine-resistant T47D cell line were inhibited by a GSI-fulvestrant combination CONCLUSIONS: Our data indicate that combinations including endocrine therapy and Notch inhibitors deserve further investigation in endocrine-resistant ERα-positive breast cancer.


Asunto(s)
Androstadienos/uso terapéutico , Antineoplásicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Benzazepinas/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Fluorocarburos/uso terapéutico , Anciano , Neoplasias de la Mama/patología , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Femenino , Humanos , Dosis Máxima Tolerada , Persona de Mediana Edad , Metástasis de la Neoplasia , Receptor Notch3 , Receptores Notch/uso terapéutico
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