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1.
ACS Appl Bio Mater ; 6(3): 973-986, 2023 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-36786674

RESUMO

Coordination of clinically employed bisphosphonate, risedronate (RISE), to bioactive metals, Ca2+, Mg2+, and Zn2+, allowed the formation of bisphosphonate-based coordination complexes (BPCCs). Three RISE-based BPCCs, RISE-Ca, RISE-Mg, and RISE-Zn, were produced, and their structures were elucidated by single crystal X-ray diffraction. Interestingly, the addition of an auxiliary ligand, etidronic acid (HEDP), resulted in the recrystallized protonated form of the ligand, H-RISE. The pH-dependent structural stability of the RISE-based BPCCs was measured by means of dissolution profiles under neutral and acidic simulated physiological conditions (PBS and FaSSGF, respectively). In comparison to RISE (Actonel), the complexes showed a lower equilibrium solubility (∼70-85% in 18-24 h) in PBS, while a higher equilibrium solubility (∼100% in 3 h) in acidic media. The results point to the capacity to release this BP in a pH-dependent manner from the RISE-based BPCCs. Subsequently, the particle size of RISE-Ca was reduced, from 300 µm to ∼350 d.nm, employing the phase inversion temperature (PIT)-nanoemulsion method, resulting in nano-Ca@RISE. Aggregation measurements of nano-Ca@RISE in 1% fetal bovine serum (FBS):H2O was monitored after 24, 48, and 72 h to study the particle size longevity in physiological media, showing that the suspended material has the potential to maintain its particle size over time. Furthermore, binding assays were performed to determine the potential binding of nano-Ca@RISE to the bone, where results show higher binding (∼1.7×) for the material to hydroxyapatite (HA, 30%) when compared to RISE (17%) in 1 d. The cytotoxicity effects of nano-Ca@RISE were compared to those of RISE against the human breast cancer MDA-MB-231 and normal osteoblast-like hFOB 1.19 cell lines by dose-response curves and relative cell viability assays in an in vitro setting. The results demonstrate that nano-Ca@RISE significantly decreases the viability of MDA-MB-231 with high specificity, at concentrations ∼2-3× lower than the ones reported employing other third-generation BPs. This is supported by the fact that when normal osteoblast cells (hFOB 1.19), which are part of the tissue microenvironment at metastatic sites, were treated with nano-Ca@RISE no significant decrease in viability was observed. This study expands on the therapeutic potential of RISE beyond its antiresorptive activity through the design of BPCCs, specifically nano-Ca@RISE, that bind to the bone and degrade in a pH-dependent manner under acidic conditions.


Assuntos
Complexos de Coordenação , Humanos , Ácido Risedrônico/química , Ligantes , Difosfonatos/farmacologia , Difosfonatos/uso terapêutico , Ácido Etidrônico/farmacologia , Ácido Etidrônico/uso terapêutico , Ácido Etidrônico/química
2.
Inorg Chem ; 62(1): 201-212, 2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36546849

RESUMO

Functionalization of highly pure rutile phase titanium dioxide (TiO2) particles with a selected bisphosphonate-based coordination complex (BPCC), ZOLE-Ca form II, was achieved through in situ surface crystallization. The hydrothermal reaction of the selected BPCC was carried out in the presence of photoactivated rutile phase TiO2 by ultraviolet irradiation. The reaction time was varied to control the crystal growth of the BPCC around the TiO2 core, resulting in a functionalized material with different shell thicknesses: TiO2-core:nano-Ca@ZOLE-shell-† (5 min) and TiO2-core:nano-Ca@ZOLE-shell-‡ (10 min). The crystal phase assessment of the BPCC and the polymorphic phase purity of the metal oxide were determined after immobilization through Raman spectroscopy and powder X-ray diffraction. The results initially suggested that the crystallization of a shell comprising the selected BPCC surrounding a highly pure rutile phase TiO2 core was achieved through controlled in situ surface crystallization. Morphological changes, elemental composition and exact atomic distribution in the functionalized materials were addressed employing scanning electron microscopy coupled with energy-dispersive spectroscopy. These analyses unambiguously confirmed that after 5 min, successful incorporation of a thin BPCC shell on the surface of the metal oxide particles was achieved. Particle size distribution measurements revealed an average particle size of 495 d.nm for the functionalized material after the immobilization process. Quantitative determination of the BPCC shell content in TiO2-core:nano-Ca@ZOLE-shell-† was determined through thermogravimetric analysis, estimating a ratio of ∼1:3 (TiO2:BPCC). The cytotoxicity of TiO2-core:nano-Ca@ZOLE-shell-† against MDA-MB-231 (cancer cell model) and hFOB 1.19 (normal osteoblast-like cell model) cell lines was investigated. The results demonstrated significant cell growth inhibition for TiO2-core:nano-Ca@ZOLE-shell-† against MDA-MB-231, specifically at a concentration of 7.5 µM (% RCL = 46 ± 2%, 72 h). Under the same conditions, the functionalized material did not present cytotoxicity against hFOB 1.19 (% RCL ∼ 100%). These important outcomes provide evidence of the surface crystallization of BPCCs onto rutile phase TiO2 for the development of a novel functionalized material with the potential to treat and prevent osteolytic metastases.


Assuntos
Complexos de Coordenação , Cristalização , Titânio/química , Óxidos
3.
PLoS Negl Trop Dis ; 13(9): e0007715, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31553732

RESUMO

BACKGROUND: The National Program for Chagas disease was implemented in Bolivia in 2006, and it greatly decreased the number of infections through vector control. Subsequently, a treatment regimen of benznidazole (BNZ) was started in seropositive school-age children living in certified vector control areas. METHODS AND FINDINGS: We conducted a 12-month follow-up study and seven blood samples were taken during and after the treatment. Serology, conventional diagnostic PCR (cPCR) and quantitative Real-time PCR (qPCR) were performed. Plasma Th1/Th2/Th17 cytokines levels were also determined. Approximately 73 of 103 seropositive children complied with BNZ, with three interruptions due to side effects. To evaluate each individual's treatment efficacy, the cPCR and qPCR values during the final 6 months of the follow-up period were observed. Among 57 children who completed follow-up, 6 individuals (11%) showed both cPCR(+) and qPCR(+) (non reactive), 24 (42%) cPCR(-) but qPCR(+) (ambiguous) and 27 (47%) cPCR(-) and qPCR(-) (reactive). Within 14 Th1/Th2/Th17 cytokines, IL-17A showed significantly higher levels in seropositive children before the treatment compared to age-matched seronegative children and significantly decreased to the normal level one-year after. Moreover, throughout the follow-up study, IL-17A levels were positively co-related to parasite counts detected by qPCR. At the 12 months' time point, IL-17A levels of non-reactive subjects were significantly higher than either those of reactive or ambiguous subjects suggesting that IL-17A might be useful to determine the reactivity to BNZ treatment. CONCLUSIONS: Plasma levels of IL-17A might be a bio-marker for detecting persistent infection of T. cruzi and its chronic inflammation.


Assuntos
Doença de Chagas/tratamento farmacológico , Interleucina-17/sangue , Nitroimidazóis/uso terapêutico , Resultado do Tratamento , Adolescente , Biomarcadores/sangue , Bolívia , Doença de Chagas/sangue , Criança , Pré-Escolar , Citocinas , Feminino , Seguimentos , Humanos , Masculino , Nitroimidazóis/sangue , Reação em Cadeia da Polimerase/métodos , Tripanossomicidas/sangue , Tripanossomicidas/uso terapêutico , Trypanosoma cruzi/efeitos dos fármacos , Trypanosoma cruzi/isolamento & purificação
4.
Korean J Parasitol ; 55(4): 409-416, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28877572

RESUMO

The high prevalence of pediculosis capitis, commonly known as head lice (Pediculus humanus capitis) infestation, has led to the preparation of a community-based pediculicidal ointment, which is made of common household items and the extract of Tinospora crispa stem. The present study aimed to evaluate the safety, efficacy, and physicochemical characteristics of the T. crispa pediculicidal ointment. The physicochemical properties of the ointment were characterized, and safety was determined using acute dermal irritation test (OECD 404), while the efficacy was assessed using an in vitro pediculicidal assay. Furthermore, the chemical compounds present in T. crispa were identified using liquid-liquid extraction followed by ultra-performance liquid chromatography quadruple time-of-flight mass spectrometric (UPLC-qTOF/MS) analysis. The community-based ointment formulation was light yellow in color, homogeneous, smooth, with distinct aromatic odor and pH of 6.92±0.09. It has spreadability value of 15.04±0.98 g·cm/sec and has thixotropic behavior. It was also found to be non-irritant, with a primary irritation index value of 0.15. Moreover, it was comparable to the pediculicidal activity of the positive control Kwell®, a commercially available 1% permethrin shampoo (P>0.05), and was significantly different to the activity of the negative control ointment, a mixture of palm oil and candle wax (P<0.05). These findings suggested that the community-based T. crispa pediculicidal ointment is safe and effective, having acceptable physicochemical characteristics. Its activity can be attributed to the presence of compounds moupinamide and physalin I.


Assuntos
Composição de Medicamentos , Infestações por Piolhos/tratamento farmacológico , Infestações por Piolhos/parasitologia , Pediculus , Fitoterapia , Extratos Vegetais , Tinospora/química , Animais , Fenômenos Químicos , Ácidos Cumáricos/análise , Pomadas , Pediculus/efeitos dos fármacos , Praguicidas , Extratos Vegetais/efeitos adversos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Segurança , Secoesteroides/análise , Testes de Irritação da Pele , Tiramina/análogos & derivados , Tiramina/análise
5.
Acta biol. colomb ; 20(1): 109-116, ene.-abr. 2015. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-734905

RESUMO

Los marcadores genéticos del pelaje y malformaciones óseas han permitido caracterizar el perfil genético de más de 400 poblaciones del gato doméstico alrededor del mundo. Hace 15 años se estableció dicho perfil en la ciudad de Cali (Colombia). En este estudio se determinó si el norte y sur de Cali se comportan como subpoblaciones y se comparó el perfil total con el estudio pasado. Se encontró una disminución de la frecuencia alélica de a (no-agouti) y d (dilution), pero un aumento en cinco, especialmente en l (longhair) y c s (siamese). Dichas diferencias pueden atribuirse a la selección humana de características más atractivas y por el flujo génico resultante del crecimiento demográfico de la ciudad, lo que explicaría también el primer reporte de los alelos inhibitor y ticked abyssinian. Se evaluó el equilibrio Hardy-Weinberg para el norte, sur y las dos zonas juntas, usando los loci white spotting y orange, encontrándose desequilibrio en este último para las tres zonas evaluadas debido a un déficit de heterocigotos. Norte y sur se dividieron en dos, y cada sub-muestra presentó equilibrio Hardy-Weinberg, aunque las diferencias en las frecuencias alélicas y heterocigosidades resaltaron microestructura geográfica y una relación entre tiempo de fundación del barrio y heterocigosidad. Norte y sur resultaron ser una población y no subpoblaciones (F ST= 0,0004, D= 0,0017), al igual que las nueve poblaciones colombianas con las que se comparó la presente ciudad. Se sugiere realizar un análisis microgeográfico de flujo génico y la definición de posibles colonias de gatos en Cali.


The coat genetic markers and skeleton abnormalities have allowed characterize the profile from more than 400 domestic cat populations around the world. 15 years ago, that profile was established in the city of Cali (Colombia). In this study it was determined if north and south of the city are subpopulations and it was compared the total profile against past study. A decrease in allele frequency of a (non-agouti) and d (dilution) was found, but an increase of five alleles was found, especially in l (long hair) and c s (siamese). These differences could be attributed to human selection of more attractive characteristics and gene flow resulting from demographic growth city, which would also explain the first report of inhibitor and ticked abyssinian alleles. Hardy-Weinberg equilibrium was evaluated for the north, south and both areas together, using white spotting and orange loci, determining disequilibrium in orange for the three evaluated areas due to a heterozygotes deficit. North and south were divided into two, each sub-sample showed Hardy-Weinberg equilibrium, although allele frequencies and heterozygosities highlighted microgeographic structure and a relationship between founding time of the neighborhood and heterozygosity. North and south are a single population and aren´t subpopulations (F ST= 0,0004, D= 0,0017), as well as nine Colombian populations with which this city was compared. It is suggested to make a microgeographical gene flow analysis and the definition of possible cat colonies in Cali.

6.
J Immigr Minor Health ; 14(3): 512-5, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21909984

RESUMO

Pediatric obesity continues to be an epidemic, affecting Hispanic children disproportionately. Recent recommendations outline a step-wise approach to the treatment of overweight and obese children, culminating in tertiary-care, multidisciplinary programs. We detail here how our tertiary-care, family-based, pediatric weight management clinic addressed the problem of few Spanish-speaking families enrolling in treatment after referral by adding a Bilingual Case Manager. Utilizing a family-centered, high-contact, personal approach, our program increased the number of Hispanic families enrolling over ten-fold. Further, outcomes in Hispanic families were equal to or better than other racial/ethnic groups. Lessons learned from this experience may benefit other obesity treatment programs trying to improve care of Spanish-speaking families.


Assuntos
Instituições de Assistência Ambulatorial/organização & administração , Hispânico ou Latino/estatística & dados numéricos , Idioma , Obesidade/prevenção & controle , Pediatria , Programas de Redução de Peso/organização & administração , Criança , Proteção da Criança , Cultura , Feminino , Educação em Saúde/métodos , Conhecimentos, Atitudes e Prática em Saúde , Promoção da Saúde , Humanos , Masculino , Obesidade/epidemiologia , Obesidade/etnologia , Desenvolvimento de Programas , Avaliação de Programas e Projetos de Saúde , Marketing Social
7.
J Orthomol Med ; 25(1): 29-38, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-23565030

RESUMO

Ascorbic Acid (AA) has been used in the prevention and treatment of cancer with reported effectiveness. Mitochondria may be one of the principal targets of ascorbate's cellular activity and it may play an important role in the development and progression of cancer. Mitochondria, besides generating adenosine triphosphate (ATP), has a role in apoptosis regulation and in the production of regulatory oxidative species that may be relevant in gene expression. At higher concentrations AA may increase ATP production by increasing mitochondrial electron flux, also may induce apoptotic cell death in tumor cell lines, probably via its pro-oxidant action In contrast, at lower concentrations AA displays antioxidant properties that may prevent the activation of oxidant-induced apoptosis. These concentration dependent activities of ascorbate may explain in part the seemingly contradictory results that have been reported previously.

8.
Am J Health Behav ; 33(5): 581-6, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19296748

RESUMO

OBJECTIVE: To describe promising recruitment and retention strategies for transient Latino populations, assisting investigators who work with this population in their research design and implementation. METHODS: Strategies in recruitment and retention from a year-long intervention in children and their families are described. RESULTS: Of the 159 families who agreed to participate in the program, 123 parent-child dyads were enrolled. Retention rates were 59% in the control group, 67% in the intervention group. CONCLUSION: Building and maintaining relationships between a consistent study team contact and participants promote strong recruitment and retention outcomes. Barriers such as child care and transportation must be minimized.


Assuntos
Hispânico ou Latino , Estilo de Vida , Seleção de Pacientes , Adulto , Criança , Cuidado da Criança , Feminino , Humanos , Masculino , North Carolina , Relações Pais-Filho , Ensaios Clínicos Controlados Aleatórios como Assunto , Meios de Transporte
9.
J Ethnopharmacol ; 109(3): 523-8, 2007 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-17088036

RESUMO

The cortex of Mimosa tenuiflora is a popular remedy utilized in Mexico for the treatment of skin lesions. Modern studies support the existence in this cortex of compounds with cicatrizing properties. In the present study the therapeutic effectiveness of an extract elaborated with this bark in the treatment of venous leg ulceration disease was explored. A randomized, double-blind, placebo-controlled clinical trial was conducted with ambulatory patients distributed into two groups, one receiving a hydrogel containing 5% of a crude extract standardized in its tannin concentration (1.8%), while the control group, was administered the same hydrogel but without addition of the extract. In both aseptic washings were performed initially followed by topical application of the corresponding hydrogel and dressing. Follow-up lasted 13 weeks and ulcer healing was determined through measurement of the lesion area by digital-photographic parameters. Therapeutic effectiveness occurred in all patients of the extract group; after the 8th treatment week, ulcer size was reduced by 92% as mean value in this group, whereas therapeutic effectiveness was observed only in one patient of the control group (chi(2), p=0.0001). No side effects were observed in any patient in either group.


Assuntos
Úlcera da Perna/tratamento farmacológico , Mimosa/química , Adulto , Idoso , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fitoterapia , Extratos Vegetais/uso terapêutico , Resultado do Tratamento
10.
P R Health Sci J ; 25(1): 71-3, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16883681

RESUMO

Many mathematical models have been proposed to study tumor growth parameters in vivo. Nevertheless most of the medical models have given variable results even when experimental conditions are exactly the same. There are multiple factors that are capable of affecting tumor growth that should be taken into account when proposing a mathematical model for tumor growth in vivo. We discuss here own proposed model for tumor growth kinetics utilizing a modified Gompertz function that better responds to the growth characteristic of in "vivo" tumors.


Assuntos
Neoplasias da Mama/patologia , Modelos Teóricos , Proliferação de Células , Humanos , Cinética
11.
P R Health Sci J ; 24(3): 211-3, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16329685

RESUMO

A dietary supplement combination consisting of vitamins, minerals and fibers was studied to determine its safety and efficacy on weight/fat loss, cholesterol and triglycerides in children between ages 7-13. This open label trial measured total body weight, body fat percentage, waist circumference, total cholesterol, triglycerides before and after 6 weeks of treatment. The study population consisted of 25 mildly to moderate obese, otherwise healthy children of both sexes. After 6 weeks of treatment, the combination supplement had a statistically significant (p < 0.05) weight reducing effect. This weight reduction was associated with a corresponding statistically significant (p < 0.0001l) decrease in body fat percentage. In addition, significant decreases in total cholesterol (p < 0.0001) and triglycerides (p < 0.0001) were obtained, plus reductions in waist measurements. We conclude that the combination supplement studied herein is a safe and effective way to assist children in weight, fat percentage, cholesterol and triglyceride reduction.


Assuntos
Tecido Adiposo , Colesterol/sangue , Suplementos Nutricionais , Obesidade/sangue , Obesidade/terapia , Triglicerídeos/sangue , Redução de Peso , Adolescente , Criança , Feminino , Humanos , Masculino
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