Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 41
Filter
Add more filters

Publication year range
1.
Am J Perinatol ; 2024 May 07.
Article in English | MEDLINE | ID: mdl-38714205

ABSTRACT

OBJECTIVE: This study aimed to assess the viability of implementing a tele-educational training program in neurocritical care for newborns diagnosed with hypoxic-ischemic encephalopathy (HIE) and treated with therapeutic hypothermia (TH), with the goal of reducing practice variation. STUDY DESIGN: Prospective study including newborns with HIE treated with TH from 12 neonatal intensive care units in Brazil conducted from February 2021 to February 2022. An educational intervention consisting of 12 biweekly, 1-hour, live videoconferences was implemented during a 6-month period in all centers. Half of the centers had the assistance of a remote neuromonitoring team. The primary outcome was the rate of deviations from TH protocol, and it was evaluated during a 3-month period before and after the intervention. Logistic regression via generalized estimating equations was performed to compare the primary and secondary outcomes. Protocol deviations were defined as practices not in compliance with the TH protocol provided. A subanalysis evaluated the differences in protocol deviations and clinical variables between centers with and without neuromonitoring. RESULTS: Sixty-six (39.5%) newborns with HIE were treated with TH during the preintervention period, 69 (41.3%) during the intervention period and 32 (19.1%) after intervention. There was not a significant reduction in protocol deviations between the pre- and postintervention periods (37.8 vs. 25%, p = 0.23); however, a decrease in the rates of missing Sarnat examinations within 6 hours after birth was seen between the preintervention (n = 5, 7.6%) and postintervention (n = 2, 6.3%) periods (adjusted odds ratio [aOR]: 0.36 [0.25-0.52], p < 0.001). Centers with remote neuromonitoring support had significantly lower rates of seizures (27.6 vs. 57.5%; aOR: 0.26 [0.12-0.55], p < 0.001) and significant less seizure medication (27.6 vs. 68.7%; aOR: 0.17 [0.07-0.4], p < 0.001). CONCLUSION: This study shows that implementing a tele-educational program in neonatal neurocritical care is feasible and may decrease variability in the delivery of care to patients with HIE treated with TH. KEY POINTS: · Neurocritical care strategies vary widely in low- and middle-income countries.. · Heterogeneity of care may lead to suboptimal efficacy of neuroprotective strategies.. · Tele-education and international collaboration can decrease the variability of neurocritical care provided to infants with HIE..

2.
BMC Public Health ; 23(1): 1070, 2023 06 05.
Article in English | MEDLINE | ID: mdl-37277812

ABSTRACT

BACKGROUND: In collaboration with local partners, we reviewed 18 national policy documents across two sub-Saharan African countries identified as pre-dividend nations by the World Bank in 2017: Nigeria and Tanzania. Our aim was to assess national policies in pre-dividend countries and to determine whether national strategies were primed to capitalize on changing demographic structures, maximally attain the demographic dividend, and augment socio-economic growth. METHODS: We conducted policy reviews by focusing on five key sectors of the Gates Institute Demographic Dividend Framework: Family Planning, Maternal and Child Health, Education, Women's Empowerment, and Labor Market. This framework was developed as a tool for countries to apply targeted policies for accelerating the demographic dividend based on their demographic structure. For each component we used a comprehensive list of indicators, defined via a systematic literature review, through which we assessed national policies aimed at maximizing the demographic dividend. RESULTS: Between the two countries, we observed persistent gaps in policies targeting family planning. Although more comprehensive, policies addressing maternal and child health, education, women's empowerment, and labor market still lagged in their specificity and measurability. We identified specific policy amendments and alternatives that Nigeria and Tanzania could consider to mitigate these gaps. We also stress the importance of designing measurable policy initiatives across sectors. CONCLUSIONS: Based on these recommendations, as Nigeria, Tanzania, and other pre-dividend nations start experiencing rapid demographic changes, they may consider implementing routine policy reviews to strengthen policies across the five key sectors and harness the benefits of a demographic dividend.


Subject(s)
Family Planning Services , Policy , Child , Female , Humans , Nigeria , Tanzania , Demography , Developing Countries
3.
Molecules ; 26(5)2021 Mar 02.
Article in English | MEDLINE | ID: mdl-33801209

ABSTRACT

Although single targeted anti-cancer drugs are envisaged as safer treatments because they do not affect normal cells, cancer is a very complex disease to be eradicated with a single targeted drug. Alternatively, multi-targeted drugs may be more effective and the tumor cells may be less prone to develop drug resistance although these drugs may be less specific for cancer cells. We have previously developed a new strategy to endow human pancreatic ribonuclease with antitumor action by introducing in its sequence a non-classical nuclear localization signal. These engineered proteins cleave multiple species of nuclear RNA promoting apoptosis of tumor cells. Interestingly, these enzymes, on ovarian cancer cells, affect the expression of multiple genes implicated in metabolic and signaling pathways that are critic for the development of cancer. Since most of these targeted pathways are not highly relevant for non-proliferating cells, we envisioned the possibility that nuclear directed-ribonucleases were specific for tumor cells. Here, we show that these enzymes are much more cytotoxic for tumor cells in vitro. Although the mechanism of selectivity of NLSPE5 is not fully understood, herein we show that p27KIP1 displays an important role on the higher resistance of non-tumor cells to these ribonucleases.


Subject(s)
Cell Nucleus/metabolism , Colon/cytology , Cyclin-Dependent Kinase Inhibitor p27/metabolism , Cytoplasm/metabolism , Keratinocytes/cytology , Neoplasms/pathology , Ribonucleases/metabolism , Apoptosis , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Cells, Cultured , Colon/metabolism , Female , Humans , Keratinocytes/metabolism , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Neoplasms/metabolism , Ovarian Neoplasms/metabolism , Ovarian Neoplasms/pathology , Signal Transduction
4.
Molecules ; 23(12)2018 Dec 11.
Article in English | MEDLINE | ID: mdl-30544927

ABSTRACT

Ribonucleases are proteins whose use is promising in anticancer therapy. We have previously constructed different human pancreatic ribonuclease variants that are selectively cytotoxic for tumor cells by introducing a nuclear localization signal into their sequence. However, these modifications produced an important decrease in their stability compromising their behavior in vivo. Here, we show that we can significantly increase the thermal stability of these cytotoxic proteins by introducing additional disulfide bonds by site-directed mutagenesis. One of these variants increases its thermal stability by around 17 °C, without affecting its catalytic activity while maintaining the cytotoxic activity against tumor cells. We also show that the most stable variant is significantly more resistant to proteolysis when incubated with proteinase K or with human sera, suggesting that its half-live could be increased in vivo once administered.


Subject(s)
Protein Engineering/methods , Ribonuclease, Pancreatic/chemistry , Ribonuclease, Pancreatic/metabolism , Antineoplastic Agents/pharmacology , Cell Line, Tumor , Disulfides/chemistry , Endopeptidase K/chemistry , Endopeptidase K/metabolism , Enzyme Stability , Humans , Mutagenesis, Site-Directed , Nuclear Localization Signals/genetics , Proteolysis , Ribonuclease, Pancreatic/genetics , Ribonuclease, Pancreatic/pharmacology
5.
Invest New Drugs ; 35(3): 260-268, 2017 06.
Article in English | MEDLINE | ID: mdl-28120180

ABSTRACT

Apoptin is a nonstructural protein encoded by one of the three open reading frames of the chicken anemia virus genome. It has attracted a great deal of interest due to its ability to induce apoptosis in multiple transformed and malignant mammalian cell lines without affecting primary and non-transformed cells. However, the use of Apoptin as an anticancer drug is restricted by its strong tendency to aggregate. A number of methods to overcome this problem have been proposed, including transduction techniques to deliver the Apoptin gene into tumor cells, but all such methods have certain drawbacks. Here we describe that a truncated variant of Apoptin, lacking residues 1 to 43, is a soluble, non-aggregating protein that maintains most of the biological properties of wild-type Apoptin when transfected into cells. We show that the cytotoxic effect of this variant is also present when it is added exogenously to cancer cells, but not to normal cells. In addition to the interest this protein has attracted as a promising therapeutic strategy, it is also an excellent model to study the structural properties of Apoptin and how they relate to its mechanism of action.


Subject(s)
Antineoplastic Agents/pharmacology , Capsid Proteins/chemistry , Capsid Proteins/pharmacology , Apoptosis/drug effects , Capsid Proteins/genetics , Cell Line , Cell Line, Tumor , DNA/metabolism , Escherichia coli/genetics , Humans , Transfection
6.
Arch Biochem Biophys ; 614: 53-64, 2017 Jan 15.
Article in English | MEDLINE | ID: mdl-28034642

ABSTRACT

Apoptin is a 121 residue protein which forms large, soluble aggregates and possesses an exceptionally selectively cytotoxic action on cancer cells. In the accompanying paper, we described the design, production and initial characterization of an Apoptin truncated variant called H6-ApopΔProΔLeu. Whereas both the variant and wild type protein possess similar selective cytotoxicity against cancer cells following transfection, only the variant is cytotoxic when added externally. Remarkably, as observed by gel filtration chromatography and dynamic light scattering, H6-ApopΔProΔLeu lacks the tendency of wild type Apoptin to form large aggregates, which greatly facilitated the study of its biological properties. Here, we characterize the conformation and dynamics of H6-ApopΔProΔLeu. Using a battery of 2D, 3D and (4,2)D NMR spectra, the essentially complete 1H, 13C and 15N resonance assignments of H6-ApopΔProΔLeu were obtained. The analysis of these data shows that the variant is an intrinsically disordered protein, which lacks a preferred conformation. This conclusion is corroborated by a lack of protection against proteolytic cleavage and hydrogen/deuterium exchange. Moreover, the CD spectra are dominated by random coil contributions. Finally, 1H-15N NOE ratios are low, which indicates flexibility on the ps-ns time scale. Interestingly, H6-ApopΔProΔLeu's intrinsically disordered ensemble is not significantly altered by the redox state of its Cys residues or by Thr phosphorylation, which has been proposed to play a key role in Apoptin's selective cytotoxicity. These results serve to better comprehend Apoptin's remarkably selective anticancer action and provide a framework for the future design of improved Apoptin variants.


Subject(s)
Antineoplastic Agents/chemistry , Capsid Proteins/chemistry , Neoplasms/pathology , Neoplasms/therapy , Cell Line, Tumor , Chicken anemia virus , Cysteine/chemistry , Drug Screening Assays, Antitumor , Endopeptidase K/chemistry , Humans , Magnetic Resonance Spectroscopy , Phosphorylation , Protein Conformation , Protein Folding , Spectrometry, Fluorescence , Spectrophotometry, Ultraviolet
7.
Protein Sci ; 33(7): e5070, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38864750

ABSTRACT

Protein splicing is a self-catalyzed process in which an internal protein domain (the intein) is excised from its flanking sequences, linking them together with a canonical peptide bond. Trans-inteins are separated in two different precursor polypeptide chains that must assemble to catalytically self-excise and ligate the corresponding flanking exteins to join even when expressed separately either in vitro or in vivo. They are very interesting to construct full proteins from separate domains because their common small size favors chemical synthesis approaches. Therefore, trans-inteins have multiple applications such as protein modification and purification, structural characterization of protein domains or production of intein-based biosensors, among others. For many of these applications, when using more than one trans-intein, orthogonality between them is a critical issue to ensure the proper ligation of the exteins. Here, we confirm the orthogonality (lack of cross-reactivity) of four different trans- or split inteins, gp41-1, gp41-8, IMPDH-1 and NrdJ-1 both in vivo and in vitro, and built different constructs that allow for the sequential fusion of up to four protein fragments into one final spliced product. We have characterized the splicing efficiency of these constructs. All harbor non-native extein residues at the splice junction between the trans-intein and the neighboring exteins, except for the essential Ser + 1. Our results show that it is possible to ligate four different protein domains using inteins gp41-1, IMPDH-1 and NrdJ-1 with non-native extein residues to obtain a final four-domain spliced product with a not negligible yield that keeps its native sequence.


Subject(s)
Inteins , Protein Domains , Protein Splicing , Protein Engineering/methods , Escherichia coli/genetics , Escherichia coli/metabolism
8.
MethodsX ; 12: 102759, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38826794

ABSTRACT

In Mexico, corn and the nixtamalization technique hold immense culinary and economic significance. Thus, optimizing and offering alternatives for this process is critical. This research proposes a solar-driven nixtamalization method customized for native maize varieties in Michoacán, Mexico. The objective is to present a technique that is energy-efficient, environmentally friendly, socially acceptable, and cost-effective. We devised a straightforward yet effective nixtamalization process utilizing the HSMC solar furnace. This method encompasses:•Field research to understand the practices and traditions regarding nixtamalization and the most consumed maize varieties.•Thermal determination and profiling of the solar oven to be used for each case study.For the rural areas of Michoacán, solar nixtamalization presents a practical and eco-sustainable alternative in both energy usage and economic terms. However, those interested in its local application must consider that the duration may vary due to differing climatic conditions and maize types.

9.
J Med Chem ; 67(3): 1783-1811, 2024 Feb 08.
Article in English | MEDLINE | ID: mdl-38291666

ABSTRACT

One approach to reduce the side effects of chemotherapy in cancer treatment is photodynamic therapy (PDT), which allows spatiotemporal control of the cytotoxicity. We have used the strategy of coordinating π-expansive ligands to increase the excited state lifetimes of Ir(III) half-sandwich complexes in order to facilitate the generation of 1O2. We have obtained derivatives of formulas [Cp*Ir(C∧N)Cl] and [Cp*Ir(C∧N)L]BF4 with different degrees of π-expansion in the C∧N ligands. Complexes with the more π-expansive ligand are very effective photosensitizers with phototoxic indexes PI > 2000. Furthermore, PI values of 63 were achieved with red light. Time-dependent density functional theory (TD-DFT) calculations nicely explain the effect of the π-expansion. The complexes produce reactive oxygen species (ROS) at the cellular level, causing mitochondrial membrane depolarization, cleavage of DNA, nicotinamide adenine dinucleotide (NADH) oxidation, as well as lysosomal damage. Consequently, cell death by apoptosis and secondary necrosis is activated. Thus, we describe the first class of half-sandwich iridium cyclometalated complexes active in PDT.


Subject(s)
Antineoplastic Agents , Photochemotherapy , Photosensitizing Agents/pharmacology , Photosensitizing Agents/therapeutic use , Antineoplastic Agents/pharmacology , Ligands , Cell Line, Tumor , Iridium/pharmacology
10.
J Strength Cond Res ; 27(2): 477-84, 2013 Feb.
Article in English | MEDLINE | ID: mdl-22549084

ABSTRACT

Kettlebells are a popular implement in many strength and conditioning programs, and their benefits are touted in popular literature, books, and videos. However, clinical data on their efficacy are limited. The purpose of this study was to examine whether kettlebell training transfers strength and power to weightlifting and powerlifting exercises and improves muscular endurance. Thirty-seven subjects were assigned to an experimental (EXP, n = 23; mean age = 40.9 ± 12.9 years) or a control group (CON; n = 14; mean age = 39.6 ± 15.8 years), range 18-72 years. The participants were required to perform assessments including a barbell clean and jerk, barbell bench press, maximal vertical jump, and 45° back extensions to volitional fatigue before and after a 10-week kettlebell training program. Training was structured in a group setting for 2 d·wk(-1) for 10 weeks. A repeated measures analysis of variance was conducted to determine group × time interactions and main effects. Post hoc pairwise comparisons were conducted when appropriate. Bench press revealed a time × group interaction and a main effect (p < 0.05). Clean and jerk and back extension demonstrated a trend toward a time × group interaction, but it did not reach significance (p = 0.053). However, clean and jerk did reveal a main effect for time (p < 0.05). No significant findings were reported for maximal vertical jump. The results demonstrate a transfer of power and strength in response to 10 weeks of training with kettlebells. Traditional training methods may not be convenient or accessible for strength and conditioning specialists, athletes, coaches, and recreational exercisers. The current data suggest that kettlebells may be an effective alternative tool to improve performance in weightlifting and powerlifting.


Subject(s)
Muscle Strength , Muscle, Skeletal/physiology , Physical Endurance , Resistance Training , Weight Lifting/physiology , Adolescent , Adult , Aged , Analysis of Variance , Exercise Test , Female , Humans , Male , Middle Aged , Resistance Training/methods , Young Adult
11.
Heliyon ; 9(6): e16675, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37303520

ABSTRACT

This study presents the salient perceptions of students and instructors in a master's program taught in a hybrid virtual format using the pocket Bipolar Laddering tool, a written open-ended electronic data collection system. Perceptions about the hybrid virtual format were tested on the participants of a master's program taught in the 2021-2022 academic year through a hybrid virtual format based on a Smart Classroom system developed as part of the digital innovations implemented to overcome the COVID-19 pandemic restrictions. This work aims to shed light on the users' salient perceptions of the format, detect the positive elements mentioned by the surveyed participants and identify the negative items in a bid to minimize, or even revert, their effects for future editions of the master. As expected, the findings suggest that one of the main advantages of this format is that it allows students who have difficulty attending classes on campus to enroll on courses. However, the participants detected diverse elements that could be improved such as interaction, the degree of socialization, or the technical problems that arose during teaching sessions. It is hoped that these findings will be of use when adjusting new editions of the program and will help to determine the design and implementation of other hybrid virtual programs in the Institution.

12.
Front Psychol ; 14: 1279705, 2023.
Article in English | MEDLINE | ID: mdl-38115981

ABSTRACT

Introduction: This research is based on the role played by the entrepreneurial competence (EC), entrepreneurial education (EE) and teachers in the social, economic and cultural development of a society. The general objective of the study is to analyze the level of knowledge pre-service, those who are studying, or have recently studied, the Bachelor's Degree in Primary Education at the University of Deusto (Spain) (DPEUD) have about the EC. Methods: A questionnaire, based on EntreComp Framework, underwent expert validation and was applied to a sample of 304 students. Results: The data showed that 25% of the respondents believed that EE was related to educating through entrepreneurship; more than 45% did not know about EntreComp and EntreCompEdu, whereas only three participants were aware of how to use them; and more than 10% of the pre-service teachers did not consider assessing the CE. Discussion: These results lead to the conclusion that there is a need for EE to form part of the different national teacher training strategies; and for policy makers to include EE in the different educational frameworks, laws and decrees. In addition, it can be concluded that social, cultural and economic value can be created through entrepreneurial actions; that EC should be assessed; and that teachers should motivate students to share and implement entrepreneurial ideas and actions.

13.
J Endod ; 2023 Aug 06.
Article in English | MEDLINE | ID: mdl-37544428

ABSTRACT

INTRODUCTION: The controversial issue of whether the Archaea domain plays a role in endodontic infections is the focus of this systematic review with meta-analysis. The aim is to emphasize the significance of minority microbial domains in oral dysbiosis by evaluating the prevalence of archaea in root canals and its association with clinical parameters such as symptomatology and type of endodontic infection. METHODS: The search strategy involved researching 6 databases and the gray literature. Publications were accepted in any year or language that identified archaea in samples from endodontic canals. A 2-step selection process narrowed the final choice to 16 articles. The methodological quality of the studies was evaluated using tools from the Joanna Briggs Institute, and the certainty of evidence was assessed using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach. RESULTS: The results showed that archaea were present in 20% (95% [confidence interval] CI = 8%-32%) of individuals with endodontic samples analyzed. The samples were about twice as likely to be archaeal-positive if collected from individuals with primary vs. persistent/secondary infection (odds ratio = 2.33; 95% CI = 1.31-4.14; I2 = 0%), or individuals with self-reported vs. symptom-free infections (odds ratio = 2.67; 95% CI = 1.47-4.85; I2 = 0%). Methanogenic archaea were reported in 66% of the included studies. Representative members of phyla Thaumarchaeota and Crenarchaeota were also identified. CONCLUSIONS: Archaea are present in about one-fifth of the infected root canals. Recognized biases in experimental approaches for researching archaea must be addressed to understand the prevalence and roles of archaea in endodontic infections, and to determine whether the decontamination process should include the elimination or neutralization of archaea from root canals (International Prospective Register of Systematic Reviews protocol = CRD42021264308).

14.
J Periodontol ; 94(3): 389-404, 2023 03.
Article in English | MEDLINE | ID: mdl-36245273

ABSTRACT

BACKGROUND: This study evaluated the effects of the probiotic Bifidobacterium animalis subsp. lactis HN019 (HN019) in the development of experimental periodontitis (EP) in rats submitted to chemotherapy (5-fluorouracil [5FU]). METHODS: Eighty male rats were divided into the following groups: control (C); treated with 5FU (60 mg/kg at day 30 and 40 mg/kg at day 32); treated with probiotic (HN019) (daily, for 44 days, starting at day 0); treatment with 5FU and probiotic (5FU-HN019); only EP (EP) (ligature placed on lower first molars at day 30, maintained for 14 days); EP and treatment with 5FU (EP-5FU); EP and treatment with probiotic (EP-HN019); and EP and treatment with 5FU and probiotic (EP-5FU-HN019). Euthanasia occurred at day 44. Morphometric, histomorphometric, microtomographic, immunohistochemical, immunoenzymatic, and gene expressions analyses were performed. The data obtained were statistically analyzed (p < 0.05). RESULTS: The EP-5FU-HN019 group showed less bone and connective tissue loss when compared with EP-5FU group, while EP-HN019 and EP-5FU-HN019 groups had greater bone volume than EP and EP-5FU groups, respectively (p < 0.05). A decrease in immunostaining for tartrate-resistant acid phosphatase and RANKL, an increase for osteoprotegerin and lower interleukin-1ß levels were observed in EP-5FU-HN019 group, when compared with EP-5FU group (p < 0.0001). Probiotic therapy led to an increase in the proportions of B. lactis in the feces (p = 0.0018), but not in the biofilm, and reduced the expression of Fusobacterium nucleatum and Prevotella intermedia in the biofilm (p < 0.0001). CONCLUSION: B. lactis HN019 reduced the severity of EP in rats submitted to chemotherapy, modulating immunoinflammatory parameters in periodontal tissues and reducing periodontopathogens expression on biofilm in rats submitted to chemotherapy.


Subject(s)
Bifidobacterium animalis , Periodontitis , Probiotics , Rats , Male , Animals , Periodontitis/microbiology , Immunosuppression Therapy , Probiotics/pharmacology , Probiotics/therapeutic use , Fluorouracil/therapeutic use
15.
Biomolecules ; 13(3)2023 03 22.
Article in English | MEDLINE | ID: mdl-36979510

ABSTRACT

The number of multidrug-resistant pathogenic microorganisms has been growing in recent years, most of which is due to the inappropriate use of the commercial antibiotics that are currently available. The dissemination of antimicrobial resistance represents a serious global public health problem. Thus, it is necessary to search for and develop new drugs that can act as antimicrobial agents. Antimicrobial peptides are a promising alternative for the development of new therapeutic drugs. Anurans' skin glands are a rich source of broad-spectrum antimicrobial compounds and hylids, a large and diverse family of tree frogs, are known as an important source of antimicrobial peptides. In the present study, two novel antimicrobial peptides, named Raniseptins-3 and -6, were isolated from Boana raniceps skin secretion and their structural and biological properties were evaluated. Raniseptins-3 and -6 are cationic, rich in hydrophobic residues, and adopt an α-helix conformation in the presence of SDS (35 mM). Both peptides are active against Gram-negative bacteria and Gram-positive pathogens, with low hemolytic activity at therapeutic concentrations. No activity was observed for yeasts, but the peptides are highly cytotoxic against B16F10 murine melanoma cells and NIH3T3 mouse fibroblast cells. None of the tested compounds showed improvement trends in the MTT and LDH parameters of MHV-3 infected cells at the concentrations tested.


Subject(s)
Anti-Infective Agents , Antimicrobial Cationic Peptides , Animals , Mice , Antimicrobial Cationic Peptides/pharmacology , Antimicrobial Cationic Peptides/chemistry , Antimicrobial Peptides , NIH 3T3 Cells , Anti-Infective Agents/pharmacology , Anti-Infective Agents/chemistry , Anura , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/analysis , Microbial Sensitivity Tests , Skin/chemistry
16.
Invest New Drugs ; 30(3): 880-8, 2012 Jun.
Article in English | MEDLINE | ID: mdl-21286781

ABSTRACT

We have previously described a cytotoxic human pancreatic-ribonuclease variant, named PE5, which is able to cleave nuclear RNA, inducing the apoptosis of cancer cells. We have investigated whether PE5 could specifically inhibit the accumulation of P-glycoprotein in multidrug-resistant cells, since P-glycoprotein overexpression is one of the most important mechanisms contributing to the multiple drug resistance phenotype. We show that PE5 is able to reduce the amount of P-glycoprotein in two different multidrug-resistant cell lines, NCI/H460-R and NCI/ADR-RES, while glutathione S-transferase-л is not affected. We also show that onconase, an amphibian ribonuclease that is undergoing phase II/III clinical trials as an antitumor drug, does not affect the expression of these proteins. The reduction of P-glycoprotein accumulation, which has been functionally confirmed by flow cytometry analysis, may be caused by the previously reported underphosphorylation of JNK induced by PE5. We also show that PE5 has synergistic cytotoxicity with doxorubicin on the NCI/ADR-RES multidrug-resistant cell line. In conclusion, PE5 is a cytotoxic ribonuclease that cleaves nuclear RNA and decreases the expression of P-glycoprotein, showing anticancer activity in multidrug-resistant cell lines.


Subject(s)
Antineoplastic Agents/pharmacology , Drug Resistance, Multiple , Drug Resistance, Neoplasm , Ribonucleases/pharmacology , ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism , Cell Line, Tumor , Cell Proliferation/drug effects , Doxorubicin/pharmacology , Humans
17.
Mol Pharm ; 9(10): 2894-902, 2012 Oct 01.
Article in English | MEDLINE | ID: mdl-22957849

ABSTRACT

Ribonucleases are promising agents for use in anticancer therapy. Engineering a nuclear localization signal into the sequence of the human pancreatic ribonuclease has been revealed as a new strategy to endow this enzyme with cytotoxic activity against tumor cells. We previously described a cytotoxic human pancreatic ribonuclease variant, named PE5, which is able to cleave nuclear RNA, inducing the apoptosis of cancer cells and reducing the amount of P-glycoprotein in different multidrug-resistant cell lines. These results open the opportunity to use this ribonuclease in combination with other chemotherapeutics. In this work, we have investigated how to improve the properties of PE5 as an antitumor drug candidate. When attempting to develop a recombinant protein as a drug, two of the main desirable attributes are minimum immunogenicity and maximum potency. The improvements of PE5 have been designed in both senses. First, in order to reduce the potential immunogenicity of the protein, we have studied which residues mutated on PE5 can be reverted to those of the wild-type human pancreatic ribonuclease sequence without affecting its cytotoxicity. Second, we have investigated the effect of introducing an additional nuclear localization signal at different sites of PE5 in an effort to obtain a more cytotoxic enzyme. We show that the nuclear localization signal location is critical for the cytotoxicity. One of these variants, named NLSPE5, presents about a 10-fold increase in cytotoxicity respective to PE5. This variant induces apoptosis and kills the cells using the same mechanism as PE5.


Subject(s)
Cell Nucleus/metabolism , Nuclear Localization Signals/biosynthesis , Nuclear Localization Signals/genetics , Ribonuclease, Pancreatic/biosynthesis , Ribonuclease, Pancreatic/genetics , Antineoplastic Agents/metabolism , Apoptosis/drug effects , Apoptosis/genetics , Cell Line, Tumor , Cell Nucleus/genetics , HeLa Cells , Humans , Jurkat Cells , Mutation , Nuclear Localization Signals/administration & dosage , Nuclear Localization Signals/metabolism , RNA, Nuclear/genetics , RNA, Nuclear/metabolism , Recombinant Proteins/administration & dosage , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Ribonuclease, Pancreatic/administration & dosage , Ribonuclease, Pancreatic/metabolism
19.
J Equine Vet Sci ; 110: 103840, 2022 03.
Article in English | MEDLINE | ID: mdl-34923074

ABSTRACT

This study aimed to evaluate the in vitro antimicrobial activity of essential oils (EO) from Ocimum basilicum (basil), Rosmarinus officinalis (rosemary), and Cymbopogon citratus (lemongrass) on endometritis-causing microorganisms in mares. Serial concentrations of the EO from 30.00 mg/mL to 0.47 mg/mL were tested. The major compounds of O. basilicum EO were linalyl acetate (33.32 wt.%) and citronellal (25.06 wt.%); of R. officinalis EO were borneol (26.48 wt.%), trans-ß-ocimene (16.76 wt.%), camphene (12.45 wt.%), and α-phellandrene (11.08 wt.%); and of C. citratus EO were geranial (45.96 wt.%) and neral (32.62 wt.%). Regarding antimicrobial activity, C. citratus EO has had the highest inhibition percentage (73.9%), followed by O. basilicum (67.2%) and R. officinalis (58.7%). P. aeruginosa was the only pathogen unable to establish the minimum inhibitory concentrations (MIC) and minimum bactericidal concentration (MBC) values for the studied EO. The EOs were effective against all other microorganisms (S. equi, S. aureus, K. pneumoniae, E. coli, and C. Albicans). In conclusion, the EOs of O. basilicum, R. officinalis, and C. citratus have presented in vitro antimicrobial activity against microorganisms causing endometritis in mares.


Subject(s)
Anti-Infective Agents , Endometritis , Horse Diseases , Oils, Volatile , Animals , Anti-Infective Agents/pharmacology , Endometritis/drug therapy , Endometritis/veterinary , Escherichia coli , Female , Horses , Oils, Volatile/pharmacology , Staphylococcus aureus
20.
Pharmaceutics ; 14(12)2022 Dec 14.
Article in English | MEDLINE | ID: mdl-36559294

ABSTRACT

A family of dinuclear iron (II) compounds with iminopyridine-based ligands displays selective cytotoxic activity against cancer cell lines. All compounds have IC50 values 2-6 fold lower than that of cisplatin, and 30-90 fold lower than that of carboplatin for the tumor cell lines assayed. Comparing the IC50 values between tumor and non-tumor cell lines, the selectivity indexes range from 3.2 to 34, compound 10, [Fe2(4)2(CH3CN)4](BF4)4, showing the highest selectivity. Those compounds carrying substituents on the iminopyridine ring show the same cytotoxicity as those without substituents. However, the electronic effects of the substituents on position 6 may be important for the cytotoxicity of the complexes, and consequently for their selectivity. All compounds act over DNA, promoting cuts on both strands in the presence of reactive oxygen species. Since compound 10 presented the highest selectivity, its cytotoxic effect was further characterized. It induces apoptosis, affects cell cycle phase distribution in a cell-dependent manner, and its cytotoxic effect is linked to reactive oxygen species generation. In addition, it decreases tumor cell migration, showing potential antimetastatic effects. These properties make compound 10 a good lead antitumor agent among all compounds studied here.

SELECTION OF CITATIONS
SEARCH DETAIL