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1.
Molecules ; 29(2)2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38276623

RESUMO

Among breast cancer subtypes, triple-negative breast cancer stands out as the most aggressive, with patients facing a 40% mortality rate within the initial five years. The limited treatment options and unfavourable prognosis for triple-negative patients necessitate the development of novel therapeutic strategies. Photodynamic therapy (PDT) is an alternative treatment that can effectively target triple-negative neoplastic cells such as MDA-MB-231. In this in vitro study, we conducted a comparative analysis of the PDT killing rate of unbound Rose Bengal (RB) in solution versus RB-encapsulated chitosan nanoparticles to determine the most effective approach for inducing cytotoxicity at low laser powers (90 mW, 50 mW, 25 mW and 10 mW) and RB concentrations (50 µg/mL, 25 µg/mL, 10 µg/mL and 5 µg/mL). Intracellular singlet oxygen production and cell uptake were also determined for both treatment modalities. Dark toxicity was also assessed for normal breast cells. Despite the low laser power and concentration of nanoparticles (10 mW and 5 µg/mL), MDA-MB-231 cells experienced a substantial reduction in viability (8 ± 1%) compared to those treated with RB solution (38 ± 10%). RB nanoparticles demonstrated higher singlet oxygen production and greater uptake by cancer cells than RB solutions. Moreover, RB nanoparticles display strong cytocompatibility with normal breast cells (MCF-10A). The low activation threshold may be a crucial advantage for specifically targeting malignant cells in deep tissues.


Assuntos
Fotoquimioterapia , Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Rosa Bengala/farmacologia , Rosa Bengala/uso terapêutico , Oxigênio Singlete , Linhagem Celular Tumoral , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico
2.
Photochem Photobiol ; 100(1): 115-128, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37477110

RESUMO

Rose bengal (RB) solutions coupled with a green laser have proven to be efficient in clearing resilient nail infections caused by Trichophyton rubrum in a human pilot study and in extensive in vitro experiments. Nonetheless, the RB solution can become diluted or dispersed over the tissue and prevented from penetrating the nail plate to reach the subungual area where fungal infection proliferates. Nanoparticles carrying RB can mitigate the problem of dilution and are reported to effectively penetrate through the nail. For this reason, we have synthesized RB-encapsulated chitosan nanoparticles with a peak distribution size of ~200 nm and high reactive oxygen species (ROS) production. The RB-encapsulated chitosan nanoparticles aPDT were shown to kill more than 99% of T. rubrum, T. mentagrophytes, and T. interdigitale spores, which are the common clinically relevant pathogens in onychomycosis. These nanoparticles are not cytotoxic against human fibroblasts, which promotes their safe application in clinical translation.


Assuntos
Quitosana , Onicomicose , Humanos , Trichophyton , Rosa Bengala/farmacologia , Projetos Piloto , Onicomicose/tratamento farmacológico
3.
Molecules ; 28(19)2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37836744

RESUMO

Cancer, a prominent cause of death, presents treatment challenges, including high dosage requirements, drug resistance, poor tumour penetration and systemic toxicity in traditional chemotherapy. Photodynamic therapy, using photosensitizers like rose bengal (RB) with a green laser, shows promise against breast cancer cells in vitro. However, the hydrophilic RB struggles to efficiently penetrate the tumour site due to the unique clinical microenvironment, aggregating around rather than entering cancer cells. In this study, we have synthesized and characterized RB-encapsulated chitosan nanoparticles with a peak particle size of ~200 nm. These nanoparticles are readily internalized by cells and, in combination with a green laser (λ = 532 nm) killed 94-98% of cultured human breast cancer cells (MCF-7) and prostate cancer cells (PC3) at a low dosage (25 µg/mL RB-nanoparticles, fluence ~126 J/cm2, and irradiance ~0.21 W/cm2). Furthermore, these nanoparticles are not toxic to cultured human normal breast cells (MCF10A), which opens an avenue for translational applications.


Assuntos
Neoplasias da Mama , Nanopartículas , Fotoquimioterapia , Neoplasias da Próstata , Masculino , Humanos , Rosa Bengala/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Mama/tratamento farmacológico , Microambiente Tumoral
4.
Res Gerontol Nurs ; 15(4): 172-178, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35708962

RESUMO

Preventing acute care transfers from skilled nursing facilities (SNFs) is a challenge secondary to residents' associated debilitated status and comorbidities. Acute care transfers often result in serious complications and unnecessary health care expenditure. Literature implies that approximately two thirds of these acute care transfers could be prevented using proactive interventions. The purpose of the current study was to identify the predictors of acute care transfers for SNF residents in developing relevant prevention strategies. A retrospective chart review using multivariate logistic regression analysis showed increased odds of SNF hospitalization was significantly associated with impaired cognition, chronic obstructive pulmonary disease, and chronic kidney disease, whereas decreased odds of hospitalization was identified among non-Hispanic White residents. Study recommendations include prompt assessment of comorbid symptomatology among SNF residents for the timely management and prevention of unnecessary acute care transfers. [Research in Gerontological Nursing, 15(4), 172-178.].


Assuntos
Hospitalização , Uso Excessivo dos Serviços de Saúde , Transferência de Pacientes , Instituições de Cuidados Especializados de Enfermagem , Idoso , Disfunção Cognitiva/epidemiologia , Hospitalização/estatística & dados numéricos , Humanos , Uso Excessivo dos Serviços de Saúde/prevenção & controle , Uso Excessivo dos Serviços de Saúde/estatística & dados numéricos , Alta do Paciente , Transferência de Pacientes/estatística & dados numéricos , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Insuficiência Renal Crônica/epidemiologia , Estudos Retrospectivos , Instituições de Cuidados Especializados de Enfermagem/estatística & dados numéricos , Estados Unidos/epidemiologia
5.
DNA Cell Biol ; 41(2): 225-234, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34986032

RESUMO

Hereditary sensory neuropathy type 1A (HSN1A) is an autosomal, dominantly inherited peripheral neuropathy caused by mutations in serine palmitoyl transferase long chain 1 (SPTLC1), involved in the de novo synthesis of sphingolipids. We have previously reported calcium imbalance, as well as mitochondrial and ER stress in both HSN1 patient lymphoblasts and a transiently transfected cell model. In this study, we investigated the role of the Ca2+-activated protease calpain in destabilizing the cell cytoskeleton, by examining calpain activity in SH-SY5Y cells overexpressing the V144D mutant and changes in microtubule-associated proteins (MAP). Intramitochondrial Ca2+ was found to be significantly depleted and cytoplasmic Ca2+ increased in the V144D mutant. Subsequently, calpain and proteasome activity were increased and calpain substrates, microtubule associated proteins MAP2, and tau were significantly reduced in the microtubule fraction of the mutant. Significant changes were also found in motor proteins dynein and KIF2A detected in the microtubule fraction of cells overexpressing the V144D mutation. There was also a reduction in anterograde and retrograde mitochondrial transport velocities in the V144D mutant. These findings strongly implicate cytoskeletal aberration caused by Ca2+ dysregulation and subsequent loss of microtubule transport functions as the cause of axonal dying back that is characteristic of HSN1.


Assuntos
Cálcio
6.
J Phys Chem B ; 123(30): 6618-6626, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31274317

RESUMO

The hoisted increment in the CO2 emission in the atmosphere is a noteworthy environmental problem. Gas-liquid absorption is a well-known strategy that can be used to control CO2 emissions from an increased rate of fossil fuel industrializations. In this work, a combination of broadband dielectric spectroscopy, Fourier infrared (FTIR) spectroscopy, and quantum chemical calculations were used to study the absorption, desorption and kinetic mechanism of a room temperature imidazolium ionic liquid (IL) with cyanide anion, 1-ethyl-3-methylimidazolium thiocyanate ([EMIM][SCN]) on CO2 exposure. Initially, the charge transport and glassy dynamics of [EMIM][SCN] is investigated in a wide frequency and temperature range using broadband dielectric spectroscopy and differential scanning calorimetry. The conductivity relaxation was well fitted with Havriliak-Negami function in the modulus formalism, while the dc conductivity correlated well with the Barton-Nakajima-Namikawa relation. Then, the conductometric approach was taken to monitor the interplay between the ionic conductivity of [EMIM][SCN] and diffusion of captured CO2 in it. The resistance of the IL increases upon CO2 exposure, indicating a chemical change at the molecular level of [EMIM][SCN]. The possible CO2 capturing mechanisms for [EMIM][SCN] were investigated with density functional theory calculations and FTIR spectroscopy. Thus, this work proposes a new strategy to explain the mechanism underlined in chemisorption of CO2 in the [EMIM][SCN]. This can be extended to more promising CO2 capturing materials including ionic liquids especially imidazolium-based ionic liquids with cyanide anions like dicyanimide, tricyanometanide, tetracyanoborate, etc.

7.
J Family Med Prim Care ; 5(2): 430-434, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27843855

RESUMO

INTRODUCTION: Cancer is a major public health problem worldwide. There is an urgent need for a reinvigorated and tailored approach to promote cancer prevention and treatment-related health education, especially among the youth. OBJECTIVE: (1) To assess the knowledge and awareness of the students of adolescent age group about cancer. (2) To compare two methods of health education on improving awareness about cancer among these students. METHODOLOGY: We conducted an interventional study among students (both male and female) of adolescent age group (10-19 years) who attend Government school (Lakkur and Kugur) in Sarjapur PHC between May and September 2014. A standard pretested validated questionnaire-adopted from Cancer Awareness Measure-translated into Kannada was used. After pretest, health education was given by two modes: in Lakkur - child to child, and Kugur - routine (lecture). Following 2 days of health education, an immediate posttest was conducted. After 2 weeks, the second posttest was conducted. RESULTS: In Kugur School, 96 students and Lakkur School, 104 students participated. The mean age group of students in both the schools was 14 years. The preexisting knowledge scores between both the schools were not statistically significant. There was a significant increase in knowledge of the posttest scores in all three domains of cancer questionnaire in both the schools. Child to child program in Lakkur School was found to be more effective in increasing the knowledge scores. CONCLUSION: To increase the awareness of cancer among schools using child to child method for health education. School curriculum should include sessions on cancer education and reinforced to students periodically. To sustain this measure, school teachers could be trained in nuances of cancer prevention and treatment.

8.
Ann Plast Surg ; 62(5): 591-5, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19387168

RESUMO

Numerous techniques have been used in an attempt to achieve long-term nipple projection following nipple-areolar reconstruction (NAR). A common setback, however, is the diminution of projection over time; this phenomenon is particularly evident following implant based breast reconstruction. The purpose of this report was thus to evaluate surgical outcomes and long-term nipple projection with the use of "modified skate flap" technique in exclusively implant based postmastectomy reconstructions. A retrospective review was performed for the period between 1993 and 2007. All consecutive patients with 2-staged tissue expander/implant reconstructions followed by NAR using the modified skate flap technique performed by the senior author (P.C.) were identified in a prospectively maintained breast reconstruction database. Only patients with a minimum of 1-year follow-up were included in the study. Patients with a history of irradiation to the breast were excluded from nipple projection assessment. Clinical outcome measurements included long-term nipple projection as well as incidence of complications from the NAR procedure using the modified skate flap technique. Over the 15-year study period, 475 patients underwent 2-staged tissue expander/implant reconstruction followed by NAR using the modified skate flap technique. Of these, there was a total of 292 patients with the minimum requirement of 1-year follow-up post NAR (61% follow-up rate). The total number of reconstructed nipple areolar complexes evaluated in this series was 422 (130 bilateral and 162 unilateral NAR). Forty patients (28 unilateral and 12 bilateral NAR) who received radiation to their breasts were excluded from nipple projection assessment. At a median follow-up of 44 months (range: 12-84 months), mean nipple projection was 2.5 mm (range: 1-4 mm). Minor complications occurred in 7.2% of the patients (n = 292). Skin graft donor site dehiscence was the most common complication (3.1%) followed by partial skin graft nontake of the areola (2.1%). This report documents the largest series of NAR using a single technique in the setting of postmastectomy reconstructions. This technique can be safely performed over breast implants with acceptably low rates of complications and predictable results. Long-term nipple projection over implant reconstructions using this technique is modest and this must be forewarned to patients completing the final stage of their implant reconstruction.


Assuntos
Mamoplastia/métodos , Mamilos/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Retalhos Cirúrgicos , Adulto , Idoso , Bandagens , Implante Mamário/métodos , Implantes de Mama , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Mamilos/anatomia & histologia , Satisfação do Paciente , Estudos Retrospectivos , Transplante de Pele/métodos , Dispositivos para Expansão de Tecidos , Coleta de Tecidos e Órgãos/métodos , Resultado do Tratamento
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