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1.
PLoS One ; 19(6): e0299677, 2024.
Article in English | MEDLINE | ID: mdl-38905211

ABSTRACT

Defining the brain mechanisms underlying initial emotional evaluation is a key but unexplored clue to understanding affective processing. Event-related potentials (ERPs), especially suited for investigating this issue, were recorded in two experiments (n = 36 and n = 35). We presented emotionally negative (spiders) and neutral (wheels) silhouettes homogenized regarding their visual parameters. In Experiment 1, stimuli appeared at fixation or in the periphery (200 trials per condition and location), the former eliciting a N40 (39 milliseconds) and a P80 (or C1: 80 milliseconds) component, and the latter only a P80. In Experiment 2, stimuli were presented only at fixation (500 trials per condition). Again, an N40 (45 milliseconds) was observed, followed by a P100 (or P1: 105 milliseconds). Analyses revealed significantly greater N40-C1P1 peak-to-peak amplitudes for spiders in both experiments, and ANCOVAs showed that these effects were not explained by C1P1 alone, but that processes underlying N40 significantly contributed. Source analyses pointed to V1 as an N40 focus (more clearly in Experiment 2). Sources for C1P1 included V1 (P80) and V2/LOC (P80 and P100). These results and their timing point to low-order structures (such as visual thalamic nuclei or superior colliculi) or the visual cortex itself, as candidates for initial evaluation structures.


Subject(s)
Electroencephalography , Emotions , Photic Stimulation , Humans , Emotions/physiology , Male , Female , Adult , Young Adult , Evoked Potentials/physiology , Evoked Potentials, Visual/physiology , Visual Perception/physiology , Brain/physiology , Visual Cortex/physiology
2.
Ann Clin Biochem ; 61(2): 115-121, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37542376

ABSTRACT

INTRODUCTION AND AIMS: Sodium can be measured with direct or indirect methods; abnormal plasma total protein concentration can impact on sodium measured by indirect ion-selective electrodes (ISE). Serum sodium is an important item to determine the Model for End Stage Liver Disease Sodium (MELD-Na) score, commonly used for liver graft allocation. Patients with cirrhosis usually have hypoproteinemia. The aim of this study was to determine if there was a significant difference between the MELD-Na scores calculated based on the results of two different serum sodium ISE: indirect and direct. METHODS: This was a retrospective study; we included 166 patients that underwent liver transplant assessment, and that had paired (i.e. same date and time) direct and indirect sodium determinations. We calculated the MELD-Na scores with both sodium determinations, and we compared them. RESULTS: There was a significant difference between MELD-Na scores; the mean difference was 0.4±1.3. If MELD-Na score had been determined by the sodium measured by the direct ISE, 69 patients (42%) would have stayed in the same place on the waiting list, 67 patients (40%) would have moved up, and 30 patients (18%) would have moved down. CONCLUSIONS: There was a statistically significant difference between the MELD-Na scores calculated based on the two different sodium concentrations, which would theoretically result in changes in the order of the waiting list. This finding should prompt studies to assess if MELD-Na calculated based on direct methods has a better performance to predict clinically relevant outcomes.


Subject(s)
End Stage Liver Disease , Liver Transplantation , Humans , Sodium , End Stage Liver Disease/surgery , Cross-Sectional Studies , Retrospective Studies , Severity of Illness Index , Liver Cirrhosis/surgery , Prognosis
3.
Nanomedicine ; 52: 102695, 2023 08.
Article in English | MEDLINE | ID: mdl-37394106

ABSTRACT

Chitosan-functionalized magnetite/poly(ε-caprolactone) nanoparticles were formulated by interfacial polymer disposition plus coacervation, and loaded with gemcitabine. That (core/shell)/shell nanostructure was confirmed by electron microscopy, elemental analysis, electrophoretic, and Fourier transform infrared characterizations. A short-term stability study proved the protection against particle aggregation provided by the chitosan shell. Superparamagnetic properties of the nanoparticles were characterized in vitro, while the definition of the longitudinal and transverse relaxivities was an initial indication of their capacity as T2 contrast agents. Safety of the particles was demonstrated in vitro on HFF-1 human fibroblasts, and ex vivo on SCID mice. The nanoparticles demonstrated in vitro pH- and heat-responsive gemcitabine release capabilities. In vivo magnetic resonance imaging studies and Prussian blue visualization of iron deposits in tissue samples defined the improvement in nanoparticle targeting into the tumor when using a magnetic field. This tri-stimuli (magnetite/poly(ε-caprolactone))/chitosan nanostructure could find theranostic applications (biomedical imaging & chemotherapy) against tumors.


Subject(s)
Chitosan , Magnetite Nanoparticles , Nanoparticles , Neoplasms , Mice , Animals , Humans , Ferrosoferric Oxide/therapeutic use , Chitosan/therapeutic use , Precision Medicine , Mice, SCID , Magnetite Nanoparticles/chemistry , Neoplasms/diagnostic imaging , Neoplasms/drug therapy , Neoplasms/pathology , Gemcitabine , Magnetic Resonance Imaging/methods
4.
Front Reprod Health ; 4: 953979, 2022.
Article in English | MEDLINE | ID: mdl-36523789

ABSTRACT

Background: The foot transit of migrant peoples originating from the Caribbean, South America, Asia, and Sub-Saharan Africa through the Darién Forest (DF) in Eastern Panamá towards North America has increased in recent years from approximately 30,000 people/year to >133,000 in 2021. In the DF, there is no food/housing provision nor healthcare access. Very little is known of sexual and reproductive health (SRH) among this population. This study used rapid epidemiological methods to describe the SRH situation among migrant peoples in transit through the DF. Methods: This cross-sectional study randomly selected migrant people in transit (men and women) at a Migrant Reception Station in Darién, Panamá, between January 4-11, 2022. Data collection included a self-applied questionnaire (≥18 years); clinical screening (≥12 years); and HCG, treponemal antibodies, and HIV(I/II) lateral-flow tests with blood samples (≥12 years). Descriptive analyses were used to report findings. Results: In all, 69 men and 55 women participated in the self-applied questionnaire, 70 men and 51 women in clinical screening; 78 men and 63 women in HCG, treponemal antibody and HIV testing. Overall, 26.1% (18/69) men and 36.4% (20/55) women reported sexual intercourse within the past month. The last sex partner was casual among 43.0% (21/49) of men and 27.8% (10/36) of women; of those, 42.9% (9/21) of men and 80.0% (8/10) of women reported this sex was condomless. Among women, 20.0% (11/55) tested positive for pregnancy; 5 of these pregnancies were planned. Of those screened, a reproductive tract infection symptom was reported by 5.7% (4/70) of men and 58.8% (30/51) of women. A total of 32.7% (18/55) of men and 18.2% (8/44) of women reported no prior HIV testing. Of 78 men, HIV and treponemal antibodies were found among 1.3% (n = 1) and 2.6% (n = 2), and among 63 women, 3.2% (n = 2) and 3.2% (n = 2), respectively. Conclusions: This rapid epidemiological assessment found high recent sexual activity, low condom use with casual partners, and a need for increased HIV and syphilis testing and treatment. There is a need for increased testing, condom provision, and SRH healthcare access at migrant reception stations that receive migrant peoples in transit through Panamá.

5.
Horm Behav ; 146: 105259, 2022 11.
Article in English | MEDLINE | ID: mdl-36116197

ABSTRACT

Several studies suggest that the menstrual cycle affects emotional processing. However, these results may be biased by including women with premenstrual syndrome (PMS) in the samples. PMS is characterized by negative emotional symptomatology, such as depression and/or anxiety, during the luteal phase. This study aimed to explore the modulation of exogenous attention to emotional facial expressions as a function of the menstrual cycle in women without PMS. For this purpose, 55 women were selected (from an original volunteer sample of 790) according to rigorous exclusion criteria. Happy, angry, and neutral faces were presented as distractors, while both behavioral performance in a perceptual task and event-related potentials (ERPs) were recorded. This task was applied during both phases of the menstrual cycle (luteal and follicular, counterbalanced), and premenstrual symptomatology was monitored daily. Traditional and Bayesian ANOVAs on behavioral data (reaction times and errors in the task) and ERP indices (P1, N170, N2, and LPP amplitudes) confirmed the expected lack of an interaction of phase and emotion. Taken together, these results indicate that women free of PMS present steady exogenous attention levels to emotionally positive and negative stimuli regardless of the menstrual phase.


Subject(s)
Menstrual Cycle , Premenstrual Syndrome , Female , Humans , Bayes Theorem , Menstrual Cycle/psychology , Facial Expression , Emotions , Evoked Potentials , Premenstrual Syndrome/psychology , Electroencephalography
6.
Brain Topogr ; 35(5-6): 599-612, 2022 11.
Article in English | MEDLINE | ID: mdl-35933532

ABSTRACT

Previous research shows that dynamic stimuli, on the one hand, and emotional stimuli, on the other, capture exogenous attention due to their biological relevance. Through neural (ERPs) and behavioral measures (reaction times and errors), the present study explored the combined effect of looming motion and emotional content on attentional capture. To this end, 3D-recreated static and dynamic animals assessed as emotional (positive or negative) or neutral were presented as distractors while 71 volunteers performed a line orientation task. We observed a two-phase effect: firstly (before 300 ms), early components of ERPs (P1p and N2po) showed enhanced exogenous attentional capture by looming positive distractors and static threatening animals. Thereafter, dynamic and static threatening distractors received enhanced endogenous attention as revealed by both late ERP activity (LPC) and behavioral (errors) responses. These effects are likely explained by both the emotional valence and the distance of the stimulus at each moment.


Subject(s)
Emotions , Evoked Potentials , Photic Stimulation , Emotions/physiology , Evoked Potentials/physiology , Reaction Time/physiology , Electroencephalography
7.
Liver Int ; 42(10): 2274-2282, 2022 10.
Article in English | MEDLINE | ID: mdl-35635305

ABSTRACT

BACKGROUND AND AIMS: Cirrhosis is associated with changes in gut microbiota in both saliva and stool. The relative linkage patterns of stool versus saliva microbiota with systemic metabolomics are unclear and may differ across countries. We hypothesized that stool microbiota have greater linkages with plasma metabolites than saliva microbiota, which may depend on country of origin. METHODS: Age-balanced controls and outpatient patients with cirrhosis, compensated and decompensated, from the USA and Mexico (MX) underwent plasma collection and dietary recall. Plasma metabolomics were analysed using nuclear magnetic resonance spectroscopy. Microbiota in stool and saliva samples were analysed using 16S rRNA analyses. Correlation network differences between both saliva and stool gut microbiota and plasma metabolites were compared between subject groupings and within/between countries. RESULTS: A total of 313 age-balanced subjects-135 USA (47 control, 48 compensated and 40 decompensated) and 178 MX (71 control, 56 compensated and 51 decompensated)-were enrolled. Cirrhosis severity, including lactulose and rifaximin use, were comparable. Plasma metabolites differed with advancing cirrhosis, between countries and according to 90-day hospitalizations. Correlation networks demonstrated more microbiome-metabolite linkages in stool compared to saliva in both populations, although there were no salivary correlation metrics across decompensated subjects in either country. Stool Lactobacillus showed a positive correlation to plasma lactate in decompensated cirrhosis from MX but not USA. CONCLUSIONS: Stool microbiota were more extensively linked with systemic metabolites than were saliva microbiota, irrespective of cirrhosis severity and country. These changes were more prominent in decompensated cirrhosis and were centred around plasma lactate, which might reflect the interaction of diet and lactulose therapy.


Subject(s)
Lactulose , Microbiota , Feces , Humans , Lactates , Liver Cirrhosis/complications , RNA, Ribosomal, 16S/genetics
8.
Travel Med Infect Dis ; 47: 102317, 2022.
Article in English | MEDLINE | ID: mdl-35342009

ABSTRACT

Rapid rise of population migration is a defining feature of the 21st century due to the impact of climate change, political instability, and socioeconomic downturn. Over the last decade, an increasing number of migrant peoples travel across the Americas to reach the United States seeking asylum or cross the border undocumented in search of economic opportunities. In this journey, migrant people experience violations of their human rights, hunger, illness, violence and have limited access to medical care. In the 'Divine Comedy', the Italian poet Dante Alighieri depicts his allegorical pilgrimage across Hell and Purgatory to reach Paradise. More than 700 years after its publication, Dante's poem speaks to the present time and the perilious journey of migrant peoples to reach safehavens. By exploring the depths and heights of the human condition, Dante's struggles resonate with the multiple barriers and the unfathomable experiences faced by migrant peoples in transit across South, Central, and North America to reach the United States. Ensuring the safety of migrant peoples across the Americas and elsewhere, and attending to their health needs during their migratory paths represent modern priorities to reduce social injustices and achieving health equity.


Subject(s)
Transients and Migrants , Americas , Developing Countries , Humans , Italy , Population Dynamics , United States
9.
Sci Rep ; 12(1): 1856, 2022 02 03.
Article in English | MEDLINE | ID: mdl-35115644

ABSTRACT

Severe COVID-19 is associated with a systemic hyperinflammatory response leading to acute respiratory distress syndrome (ARDS), multi-organ failure, and death. Galectin-3 is a ß-galactoside binding lectin known to drive neutrophil infiltration and the release of pro-inflammatory cytokines contributing to airway inflammation. Thus, we aimed to investigate the potential of galectin-3 as a biomarker of severe COVID-19 outcomes. We prospectively included 156 patients with RT-PCR confirmed COVID-19. A severe outcome was defined as the requirement of invasive mechanical ventilation (IMV) and/or in-hospital death. A non-severe outcome was defined as discharge without IMV requirement. We used receiver operating characteristic (ROC) and multivariable logistic regression analysis to determine the prognostic ability of serum galectin-3 for a severe outcome. Galectin-3 levels discriminated well between severe and non-severe outcomes and correlated with markers of COVID-19 severity, (CRP, NLR, D-dimer, and neutrophil count). Using a forward-stepwise logistic regression analysis we identified galectin-3 [odds ratio (OR) 3.68 (95% CI 1.47-9.20), p < 0.01] to be an independent predictor of severe outcome. Furthermore, galectin-3 in combination with CRP, albumin and CT pulmonary affection > 50%, had significantly improved ability to predict severe outcomes [AUC 0.85 (95% CI 0.79-0.91, p < 0.0001)]. Based on the evidence presented here, we recommend clinicians measure galectin-3 levels upon admission to facilitate allocation of appropriate resources in a timely manner to COVID-19 patients at highest risk of severe outcome.


Subject(s)
COVID-19/diagnosis , COVID-19/virology , Galectins/blood , SARS-CoV-2 , Adult , Aged , Biomarkers/blood , Blood Proteins , COVID-19/complications , COVID-19/immunology , Cytokines/metabolism , Female , Humans , Inflammation , Inflammation Mediators/metabolism , Male , Middle Aged , Neutrophil Infiltration , Patient Acuity , Predictive Value of Tests , Prognosis , Prospective Studies , Respiratory Distress Syndrome/etiology , Risk
10.
Medicina (B.Aires) ; 82(1): 142-146, feb. 2022. graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1365139

ABSTRACT

Resumen Una mujer de 40 años se internó de forma programada para recibir quimioterapia por una leucemia linfoblástica aguda (LLA) B común de alto riesgo, diagnosticada 10 meses antes a raíz de hemato mas y petequias en los miembros inferiores, y metrorragia. En ese momento, presentaba trombocitopenia y una ecografía ginecológica transvaginal normal. Al ingreso de la internación programada, se quejó de dolor inguinal izquierdo con irradiación al muslo e impotencia funcional de 3 meses de evolución, dolor en fosa ilíaca derecha y diarrea. En el examen físico tenía dolor a la palpación profunda en la fosa ilíaca derecha y signo del psoas positivo a la izquierda. La tomografía de abdomen y pelvis reveló una imagen compatible con un absceso del psoas izquierdo y signos de tiflitis. La biopsia del psoas izquierdo demostró infiltración por nidos y cordones de carcinoma escamoso queratinizante moderadamente diferenciado. El examen ginecológico dirigido evidenció anomalías macroscópicas del cuello uterino correlacionadas con el mismo diagnóstico histopatológico. Los se gundos cánceres primarios más frecuentemente asociados a LLA son linfoma de Hodgkin, cáncer escamoso de piel, tumores endocrinos, cáncer renal, linfoma no-Hodgkin y cáncer de mama. Las metástasis musculares de tumores sólidos son infrecuentes, y habitualmente provienen del pulmón, riñón, tiroides y melanoma. El síndrome del psoas maligno es causado por infiltración neoplásica del músculo. El diagnóstico diferencial debe realizarse con el absceso del psoas, que puede originarse en una tiflitis si es secundario. No hemos podido encontrar registros de cáncer de cuello uterino como segundo cáncer primario luego de LLA.


Abstract A 40-year-old woman was scheduled to receive chemotherapy for a high-risk common B-cell acute lymphoblastic leukemia (ALL), diagnosed 10 months earlier in the wake of lower limb bruising and petechiae, and metrorrhagia. At that time, she had thrombocytopenia and a normal transvaginal gynecological ultrasound. Upon admission, she complained of a 3-month history of incapacitating left groin pain radiated to the thigh, and right lower quadrant abdominal pain associated with diarrhea. On physical examination, she had tenderness in the right iliac fossa and a positive psoas sign on the left. Computerized scan of the abdomen and pelvis reported an image compatible with a left psoas abscess and signs of typhlitis. The biopsy of the left psoas muscle demonstrated infiltration by nests and cords of moderately differentiated keratinizing squamous carcinoma. Gynecological examination revealed macroscopic abnormalities of the cervix correlated with the same histopathological diagnosis. The second primary cancers most frequently associated with ALL are Hodgkin lymphoma, squamous skin cancer, endocrine tumors, kidney cancer, non-Hodgkin lymphoma, and breast cancer. Muscle metastases from solid tumors are rare, and usually arise from the lung, kidney, thyroid, and melanoma. Malignant psoas syndrome is caused by neoplastic infiltration of the muscle. The differential diagnosis should be made with a psoas abscess, which may arise from typhlitis if secondary. We have not been able to find records of cervical cancer as second primary cancer after ALL.

11.
Medicina (B.Aires) ; 82(1): 161-161, feb. 2022. graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1365144
12.
Medicina (B Aires) ; 82(1): 142-146, 2022.
Article in Spanish | MEDLINE | ID: mdl-35037873

ABSTRACT

A 40-year-old woman was scheduled to receive chemotherapy for a high-risk common B-cell acute lymphoblastic leukemia (ALL), diagnosed 10 months earlier in the wake of lower limb bruising and petechiae, and metrorrhagia. At that time, she had thrombocytopenia and a normal transvaginal gynecological ultrasound. Upon admission, she complained of a 3-month history of incapacitating left groin pain radiated to the thigh, and right lower quadrant abdominal pain associated with diarrhea. On physical examination, she had tenderness in the right iliac fossa and a positive psoas sign on the left. Computerized scan of the abdomen and pelvis reported an image compatible with a left psoas abscess and signs of typhlitis. The biopsy of the left psoas muscle demonstrated infiltration by nests and cords of moderately differentiated keratinizing squamous carcinoma. Gynecological examination revealed macroscopic abnormalities of the cervix correlated with the same histopathological diagnosis. The second primary cancers most frequently associated with ALL are Hodgkin lymphoma, squamous skin cancer, endocrine tumors, kidney cancer, non-Hodgkin lymphoma, and breast cancer. Muscle metastases from solid tumors are rare, and usually arise from the lung, kidney, thyroid, and melanoma. Malignant psoas syndrome is caused by neoplastic infiltration of the muscle. The differential diagnosis should be made with a psoas abscess, which may arise from typhlitis if secondary. We have not been able to find records of cervical cancer as second primary cancer after ALL.


Una mujer de 40 años se internó de forma programada para recibir quimioterapia por una leucemia linfoblástica aguda (LLA) B común de alto riesgo, diagnosticada 10 meses antes a raíz de hematomas y petequias en los miembros inferiores, y metrorragia. En ese momento, presentaba trombocitopenia y una ecografía ginecológica transvaginal normal. Al ingreso de la internación programada, se quejó de dolor inguinal izquierdo con irradiación al muslo e impotencia funcional de 3 meses de evolución, dolor en fosa ilíaca derecha y diarrea. En el examen físico tenía dolor a la palpación profunda en la fosa ilíaca derecha y signo del psoas positivo a la izquierda. La tomografía de abdomen y pelvis reveló una imagen compatible con un absceso del psoas izquierdo y signos de tiflitis. La biopsia del psoas izquierdo demostró infiltración por nidos y cordones de carcinoma escamoso queratinizante moderadamente diferenciado. El examen ginecológico dirigido evidenció anomalías macroscópicas del cuello uterino correlacionadas con el mismo diagnóstico histopatológico. Los segundos cánceres primarios más frecuentemente asociados a LLA son linfoma de Hodgkin, cáncer escamoso de piel, tumores endocrinos, cáncer renal, linfoma no-Hodgkin y cáncer de mama. Las metástasis musculares de tumores sólidos son infrecuentes, y habitualmente provienen del pulmón, riñón, tiroides y melanoma. El síndrome del psoas maligno es causado por infiltración neoplásica del músculo. El diagnóstico diferencial debe realizarse con el absceso del psoas, que puede originarse en una tiflitis si es secundario. No hemos podido encontrar registros de cáncer de cuello uterino como segundo cáncer primario luego de LLA.


Subject(s)
Carcinoma, Squamous Cell , Psoas Abscess , Uterine Cervical Neoplasms , Adult , Biopsy , Diagnosis, Differential , Female , Humans , Psoas Abscess/diagnosis
14.
Cereb Cortex ; 32(19): 4331-4344, 2022 09 19.
Article in English | MEDLINE | ID: mdl-35059708

ABSTRACT

Several cortical and subcortical brain areas have been reported to be sensitive to the emotional content of subliminal stimuli. However, the timing of these activations remains unclear. Our scope was to detect the earliest cortical traces of emotional unconscious processing of visual stimuli by recording event-related potentials (ERPs) from 43 participants. Subliminal spiders (emotional) and wheels (neutral), sharing similar low-level visual parameters, were presented at two different locations (fixation and periphery). The differential (peak-to-peak) amplitude from CP1 (77 ms from stimulus onset) to C2 (100 ms), two early visual ERP components originated in V1/V2 according to source localization analyses, was analyzed via Bayesian and traditional frequentist analyses. Spiders elicited greater CP1-C2 amplitudes than wheels when presented at fixation. This fast effect of subliminal stimulation-not reported previously to the best of our knowledge-has implications in several debates: 1) The amygdala cannot be mediating these effects, 2) latency of other evaluative structures recently proposed, such as the visual thalamus, is compatible with these results, 3) the absence of peripheral stimuli effects points to a relevant role of the parvocellular visual system in unconscious processing.


Subject(s)
Visual Cortex , Bayes Theorem , Emotions , Evoked Potentials , Subliminal Stimulation
15.
Pharmaceutics ; 13(8)2021 Aug 10.
Article in English | MEDLINE | ID: mdl-34452193

ABSTRACT

A (core/shell)/shell nanostructure (production performance ≈ 50%, mean diameter ≈ 330 nm) was built using maghemite, PLGA, and chitosan. An extensive characterization proved the complete inclusion of the maghemite nuclei into the PLGA matrix (by nanoprecipitation solvent evaporation) and the disposition of the chitosan shell onto the nanocomposite (by coacervation). Short-term stability and the adequate magnetism of the nanocomposites were demonstrated by size and electrokinetic determinations, and by defining the first magnetization curve and the responsiveness of the colloid to a permanent magnet, respectively. Safety of the nanoparticles was postulated when considering the results from blood compatibility studies, and toxicity assays against human colonic CCD-18 fibroblasts and colon carcinoma T-84 cells. Cisplatin incorporation to the PLGA matrix generated appropriate loading values (≈15%), and a dual pH- and heat (hyperthermia)-responsive drug release behaviour (≈4.7-fold faster release at pH 5.0 and 45 °C compared to pH 7.4 and 37 °C). The half maximal inhibitory concentration of the cisplatin-loaded nanoparticles against human lung adenocarcinoma A-549 cells was ≈1.6-fold less than that of the free chemotherapeutic. Such a biocompatible and tri-stimuli responsive (maghemite/PLGA)/chitosan nanostructure may found a promising use for the effective treatment of lung cancer.

16.
J Mater Chem B ; 9(24): 4963-4980, 2021 06 23.
Article in English | MEDLINE | ID: mdl-34114575

ABSTRACT

(Maghemite/poly(d,l-lactide-co-glycolide))/chitosan (core/shell)/shell nanoparticles have been prepared reproducibly by nanoprecipitation solvent evaporation plus coacervation (production performance ≈ 45%, average size ≈ 325 nm). Transmission electron microscopy, energy dispersive X-ray spectroscopy, electrophoretic determinations, and X-ray diffraction patterns demonstrated the satisfactory embedment of iron oxide nanocores within the solid polymer matrix and the formation of an external shell of chitosan in the nanostructure. The adequate magnetic responsiveness of the nanocomposites was characterized in vitro by hysteresis cycle determinations and by visualization of the nanosystem under the influence of a 0.4 T permanent magnet. Safety and biocompatibility of the (core/shell)/shell particles were based on in vitro haemocompatibility studies and cytotoxicity tests against HFF-1 human foreskin fibroblasts and on ex vivo toxicity assessments on tissue samples from Balb/c mice. Transversal relaxivities, determined in vitro at a low magnetic field of 1.44 T, demonstrated their capability as T2 contrast agents for magnetic resonance imaging, being comparable to that of some iron oxide-based contrast agents. Heating properties were evaluated in a high frequency alternating electromagnetic gradient: a constant maximum temperature of ≈46 °C was generated within ≈50 min, while antitumour hyperthermia tests on T-84 colonic adenocarcinoma cells proved the relevant decrease in cell viability (to ≈ 39%) when treated with the nanosystem under the influence of that electromagnetic field. Finally, in vivo magnetic resonance imaging studies and ex vivo histology determinations of iron deposits postulated the efficacy of chitosan to provide long-circulating capabilities to the nanocomposites, retarding nanoparticle recognition by the mononuclear phagocyte system. To our knowledge, this is the first study describing such a type of biocompatible and long-circulating nanoplatform with promising theranostic applications (biomedical imaging and hyperthermia) against cancer.


Subject(s)
Chitosan/chemistry , Engineering , Hyperthermia, Induced , Magnetite Nanoparticles/chemistry , Nanocomposites/chemistry , Neoplasms/drug therapy , Polylactic Acid-Polyglycolic Acid Copolymer/chemistry , Cell Line, Tumor , Cell Survival/drug effects , Humans , Nanocomposites/therapeutic use
17.
Polymers (Basel) ; 12(12)2020 Nov 25.
Article in English | MEDLINE | ID: mdl-33255803

ABSTRACT

A reproducible and efficient interfacial polymer disposition method has been used to formulate magnetite/poly(ε-caprolactone) (core/shell) nanoparticles (average size ≈ 125 nm, production performance ≈ 90%). To demonstrate that the iron oxide nuclei were satisfactorily embedded within the polymeric solid matrix, a complete analysis of these nanocomposites by, e.g., electron microscopy visualizations, energy dispersive X-ray spectroscopy, Fourier-transform infrared spectroscopy, electrophoresis, and contact angle goniometry was conducted. The magnetic responsive behaviour of these nanoparticles was quantitatively characterized by the hysteresis cycle and qualitatively investigated by visualization of the colloid under exposure to a 0.4 T magnet. Gemcitabine entrapment into the polymeric shell reported adequate drug loading values (≈11%), and a biphasic and pH-responsive drug release profile (≈ four-fold faster Gemcitabine release at pH 5.0 compared to pH 7.4). Cytotoxicity studies in MCF-7 human breast cancer cells proved that the half maximal inhibitory concentration of Gem-loaded nanocomposites was ≈ two-fold less than that of the free drug. Therefore, these core/shell nanoparticles could have great possibilities as a magnetically targeted Gemcitabine delivery system for breast cancer treatment.

18.
Open Forum Infect Dis ; 7(9): ofaa359, 2020 Sep.
Article in English | MEDLINE | ID: mdl-33005697

ABSTRACT

BACKGROUND: Human cases of Madariaga virus (MADV) infection were first detected during an outbreak in 2010 in eastern Panama, where Venezuelan equine encephalitis virus (VEEV) also circulates. Little is known about the long-term consequences of either alphavirus infection. METHODS: A follow-up study of the 2010 outbreak was undertaken in 2015. An additional survey was carried out 2 weeks after a separate 2017 alphavirus outbreak in a neighboring population in eastern Panama. Serological studies and statistical analyses were undertaken in both populations. RESULTS: Among the originally alphavirus-seronegative participants (n = 35 of 65), seroconversion was observed at a rate of 14.3% (95% CI, 4.8%-30.3%) for MADV and 8.6% (95% CI, 1.8%-23.1%) for VEEV over 5 years. Among the originally MADV-seropositive participants (n = 14 of 65), VEEV seroconversion occurred in 35.7% (95% CI, 12.8%-64.9%). In the VEEV-seropositive participants (n = 16 of 65), MADV seroconversion occurred in 6.3% (95% CI, 0.2%-30.2%). MADV seroreversion was observed in 14.3% (95% CI, 1.8%-42.8%) of those who were originally seropositive in 2010. VEEV seroconversion in the baseline MADV-seropositive participants was significantly higher than in alphavirus-negative participants. In the population sampled in 2017, MADV and VEEV seroprevalence was 13.2% and 16.8%, respectively. Memory loss, insomnia, irritability, and seizures were reported significantly more frequently in alphavirus-seropositive participants than in seronegative participants. CONCLUSIONS: High rates of seroconversion to MADV and VEEV over 5 years suggest frequent circulation of both viruses in Panama. Enhanced susceptibility to VEEV infection may be conferred by MADV infection. We provide evidence of persistent neurologic symptoms up to 5 years following MADV and VEEV exposure.

19.
Semin Liver Dis ; 40(3): 321-330, 2020 08.
Article in English | MEDLINE | ID: mdl-32886936

ABSTRACT

Liver injury can result from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection with more than one-third of COVID-19 patients exhibiting elevated liver enzymes. Microvesicular steatosis, inflammation, vascular congestion, and thrombosis in the liver have been described in autopsy samples from COVID-19 patients. Several factors, including direct cytopathic effect of the virus, immune-mediated collateral damage, or an exacerbation of preexisting liver disease may contribute to liver pathology in COVID-19. Due to its immunological functions, the liver is an organ likely to participate in the viral response against SARS-CoV-2 and this may predispose it to injury. A better understanding of the mechanism contributing to liver injury is needed to develop and implement early measures to prevent serious liver damage in patients suffering from COVID-19. This review summarizes current reports of SARS-CoV-2 with an emphasis on how direct infection and subsequent severe inflammatory response may contribute to liver injury in patients with and without preexisting liver disease.


Subject(s)
Betacoronavirus , Coronavirus Infections/complications , Liver Diseases/etiology , Pandemics , Pneumonia, Viral/complications , COVID-19 , Coronavirus Infections/epidemiology , Humans , Pneumonia, Viral/epidemiology , SARS-CoV-2
20.
Pharm Dev Technol ; 25(7): 892-898, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32321344

ABSTRACT

Praziquantel (PZQ), a broad spectrum anthelmintic drug, cannot be found in acceptable dosage forms for elderly patients, paediatric patients, and for veterinary use. In fact, very little has been done up to now in the formulation of liquid dosage forms, being they always formulated for parenteral administration. To beat this important challenge, it was accomplished a comprehensive analysis of the influence of two elementary physicochemical aspects, i.e. surface thermodynamic and electrokinetic properties, on the colloidal stability of PZQ nanosuspensions. The hydrophobic character of the drug, intensely determining the flocculation curves, was confirmed by the thermodynamic characterization. The electrophoretic characterization, in combination with the sedimentation and relative absorbance versus time curves, highlighted that the electrical double layer thickness and the surface charge can play an essential role in the stability of the pharmaceutical colloid. Finally, it was demonstrated that controlling the pH values and the incorporation of electrolytes can help in formulating PZQ aqueous nanosuspensions with appropriate stability and redispersibility behaviours for pharmaceutical use.


Subject(s)
Anthelmintics/chemical synthesis , Drug Compounding/methods , Nanospheres/chemistry , Praziquantel/chemical synthesis , Anthelmintics/pharmacokinetics , Chemistry, Pharmaceutical/methods , Electrolytes/chemical synthesis , Electrolytes/pharmacokinetics , Hydrogen-Ion Concentration , Hydrophobic and Hydrophilic Interactions , Nanospheres/metabolism , Praziquantel/pharmacokinetics , Water/chemistry , Water/metabolism
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