Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 64
Filtrar
1.
Mol Cell ; 81(2): 386-397.e7, 2021 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-33340488

RESUMO

In tumors, nutrient availability and metabolism are known to be important modulators of growth signaling. However, it remains elusive whether cancer cells that are growing out in the metastatic niche rely on the same nutrients and metabolic pathways to activate growth signaling as cancer cells within the primary tumor. We discovered that breast-cancer-derived lung metastases, but not the corresponding primary breast tumors, use the serine biosynthesis pathway to support mTORC1 growth signaling. Mechanistically, pyruvate uptake through Mct2 supported mTORC1 signaling by fueling serine biosynthesis-derived α-ketoglutarate production in breast-cancer-derived lung metastases. Consequently, expression of the serine biosynthesis enzyme PHGDH was required for sensitivity to the mTORC1 inhibitor rapamycin in breast-cancer-derived lung tumors, but not in primary breast tumors. In summary, we provide in vivo evidence that the metabolic and nutrient requirements to activate growth signaling differ between the lung metastatic niche and the primary breast cancer site.


Assuntos
Neoplasias da Mama/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/genética , Neoplasias Mamárias Experimentais/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Fosfoglicerato Desidrogenase/genética , Serina/biossíntese , Animais , Antibióticos Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Ácidos Cetoglutáricos/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundário , Neoplasias Mamárias Experimentais/tratamento farmacológico , Neoplasias Mamárias Experimentais/metabolismo , Neoplasias Mamárias Experimentais/patologia , Alvo Mecanístico do Complexo 1 de Rapamicina/antagonistas & inibidores , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transportadores de Ácidos Monocarboxílicos/genética , Transportadores de Ácidos Monocarboxílicos/metabolismo , Fosfoglicerato Desidrogenase/antagonistas & inibidores , Fosfoglicerato Desidrogenase/metabolismo , Ácido Pirúvico/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Transdução de Sinais , Sirolimo/farmacologia
2.
PLoS Genet ; 20(5): e1011236, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38722825

RESUMO

Patients with ER-negative breast cancer have the worst prognosis of all breast cancer subtypes, often experiencing rapid recurrence or progression to metastatic disease shortly after diagnosis. Given that metastasis is the primary cause of mortality in most solid tumors, understanding metastatic biology is crucial for effective intervention. Using a mouse systems genetics approach, we previously identified 12 genes associated with metastatic susceptibility. Here, we extend those studies to identify Resf1, a poorly characterized gene, as a novel metastasis susceptibility gene in ER- breast cancer. Resf1 is a large, unstructured protein with an evolutionarily conserved intron-exon structure, but with poor amino acid conservation. CRISPR or gene trap mouse models crossed to the Polyoma Middle-T antigen genetically engineered mouse model (MMTV-PyMT) demonstrated that reduction of Resf1 resulted in a significant increase in tumor growth, a shortened overall survival time, and increased incidence and number of lung metastases, consistent with patient data. Furthermore, an analysis of matched tail and primary tissues revealed loss of the wildtype copy in tumor tissue, consistent with Resf1 being a tumor suppressor. Mechanistic analysis revealed a potential role of Resf1 in transcriptional control through association with compound G4 quadruplexes in expressed sequences, particularly those associated with ribosomal biogenesis. These results suggest that loss of Resf1 enhances tumor progression in ER- breast cancer through multiple alterations in both transcriptional and translational control.


Assuntos
Proteínas Repressoras , Neoplasias de Mama Triplo Negativas , Animais , Feminino , Humanos , Camundongos , Linhagem Celular Tumoral , Quadruplex G , Regulação Neoplásica da Expressão Gênica , Genes Supressores de Tumor , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/secundário , Neoplasias Pulmonares/patologia , Metástase Neoplásica , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo
3.
J Pediatr Nurs ; 75: 8-15, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38091927

RESUMO

BACKGROUND: Obtaining accurate information is critical for youth's sexual and reproductive health (SRH). Youth not in foster care often learn about SRH from their biological parents. Separated from their biological parents, youth in care depend on healthcare providers and caregivers for SRH information. However, they often receive insufficient information and feel unsupported in meeting their needs for SRH information. PURPOSE: This study explored female African American adolescents in foster care's perspectives on effective SRH communication with caregivers to help them avoid sexual risks. METHODS: A qualitative study was conducted using semi-structured interviews. We used purposive sampling to recruit 16 adolescents aged 18 to 20 years old with a history of foster care placement. The transcribed interviews underwent inductive thematic analysis. The Positive Youth Development theory underpinned this research. RESULTS: Two prominent themes emerged: establishing a relationship and preferred communication approach. Youth reported that for caregivers to engage in effective SRH communication, they must first establish a relationship by being aware of the youth's childhood trauma, building trust, having patience, and being vulnerable. Youth also appreciated caregivers who ensured comfortability and were honest and straightforward. DISCUSSION: Caregivers should be trained on adverse childhood experiences, trauma-informed approaches, SRH knowledge, and communication. IMPLICATIONS TO PRACTICE: Healthcare providers should make use of the time spent with youth and discuss SRH topics during clinical encounters. This time spent with youth may be their only chance to obtain accurate SRH information. Youth's perspectives regarding communication about SRH should be implemented in future SRH communication interventions.


Assuntos
Comunicação em Saúde , Saúde Reprodutiva , Adolescente , Feminino , Humanos , Adulto Jovem , Negro ou Afro-Americano , Cuidadores , Comportamento Sexual
4.
PLoS Genet ; 16(5): e1008743, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32463822

RESUMO

Metastasis remains the principle cause of mortality for breast cancer and presents a critical challenge because secondary lesions are often refractory to conventional treatments. While specific genetic alterations are tightly linked to primary tumor development and progression, the role of genetic alteration in the metastatic process is not well-understood. The theory of tumor evolution postulated by Peter Nowell in 1976 has yet to be proven in the context of metastasis. Therefore, in order to investigate how somatic evolution contributes to breast cancer metastasis, we performed exome, whole genome, and RNA sequencing of matched metastatic and primary tumors from pre-clinical mouse models of breast cancer. Here we show that in a treatment-naïve setting, recurrent single nucleotide variants and copy number variation, but not gene fusion events, play key metastasis-driving roles in breast cancer. For instance, we identified recurrent mutations in Kras, a known driver of colorectal and lung tumorigenesis that has not been previously implicated in breast cancer metastasis. However, in a set of in vivo proof-of-concept experiments we show that the Kras G12D mutation is sufficient to significantly promote metastasis using three syngeneic allograft models. The work herein confirms the existence of metastasis-driving mutations and presents a novel framework to identify actionable metastasis-targeted therapies.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Genômica/métodos , Mutação , Animais , Células Cultivadas , Evolução Clonal/genética , Análise Mutacional de DNA/métodos , Modelos Animais de Doenças , Progressão da Doença , Feminino , Células HEK293 , Xenoenxertos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Nus , Camundongos Transgênicos , Modelos Biológicos , Metástase Neoplásica , Sequenciamento do Exoma
5.
Int Urogynecol J ; 33(3): 487-491, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34100976

RESUMO

INTRODUCTION AND HYPOTHESIS: Patients with interstitial cystitis/bladder pain syndrome (IC/BPS) often experience chronic pelvic and even systemic pain that can be difficult to clinically manage. Pulsed electromagnetic field (PEMF) therapy, a non-invasive strategy that has shown significant efficacy for pain reduction in other chronic pain conditions, may provide benefit for pain management in patients with IC/BPS. METHODS: PEMF delivery to patients occurs via a bio-electromagnetic-energy device which consists of a flexible mat (180 × 50 cm) that the patient lies on for systemic, full-body delivery and/or a flexible pad (50 × 15 cm) for targeted delivery to a specific body region (e.g., pelvic area). The duration of individual sessions, number of sessions per day, total number of sessions, and follow-up observation period vary between previously published studies. Positive outcomes are typically reported as a significant reduction in visual analog scale (VAS) pain score and functional improvement assessed using validated questionnaires specific to the condition under study. RESULTS AND CONCLUSIONS: The use of PEMF has been evaluated as a therapeutic strategy for pain management in several clinical scenarios. Randomized, double-blinded, placebo-controlled trials have reported positive efficacy and safety profiles when PEMF was used to treat non-specific low back pain, patellofemoral pain syndrome, chronic post-operative pain, osteoarthritis-related pain, rheumatoid arthritis-related pain, and fibromyalgia-related pain. Based on these positive outcomes in a variety of pain conditions, clinical trials to evaluate whether PEMF can provide a safe, non-invasive therapeutic approach to improve symptoms of chronic pain and fatigue in patients with IC/BPS are warranted.


Assuntos
Cistite Intersticial , Terapia Combinada , Cistite Intersticial/complicações , Cistite Intersticial/diagnóstico , Cistite Intersticial/terapia , Campos Eletromagnéticos , Humanos , Dor , Manejo da Dor/métodos
6.
Cult Health Sex ; 24(11): 1481-1497, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-34524073

RESUMO

Intimate partner violence is an ongoing issue in South Africa, which has the highest rates of violence against women and girls in the world. Intimate partner violence is common in Limpopo, where women, including university students, experience elevated rates of violent crime. This qualitative study was conducted to examine university students' perspectives regarding intimate partner violence among their peers. A culturally tailored vignette was used to prompt reflection from 38 female university students in Limpopo. Audiotaped responses to the vignette were transcribed, coded and analysed using thematic analysis. Four main themes were developed from participants' responses to the vignette: cultural beliefs, the university's role in intimate partner violence, likely outcomes of intimate partner violence, and future interventions. Intimate partner violence was seen as a common problem within the university. Students' responses indicated that cultural beliefs perpetuated violence against women, with women entering and remaining in abusive relationships for financial security or resources such as housing. Students also reported lack of adequate on-campus housing options, limited knowledge of intimate partner violence, and few actions to reduce intimate partner violence, all of which placed then at heightened risk of intimate partner violence.


Assuntos
Violência por Parceiro Íntimo , Feminino , Humanos , África do Sul , Universidades , Pesquisa Qualitativa , Estudantes
7.
J Pediatr Nurs ; 56: 47-53, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33181373

RESUMO

PURPOSE: Youth in foster care are at greater risk for engaging in sexual behaviors that increase their odds of experiencing negative sexual and reproductive health (SRH) outcomes. The purpose of this qualitative study was to describe challenges faced by female African American adolescents in foster care as they tried to protect themselves from SRH risks and protective beliefs and behaviors to avoid these risks. DESIGN AND METHODS: Semi-structured interviews were conducted with 16 female African American adolescents, ages 18-20 years, with a history of foster care placement during adolescence. Purposive sampling was done to recruit participants from a metropolitan area in Virginia. Transcribed interviews underwent inductive thematic analysis. This paper focuses on the theme of protection from SRH risks and its subthemes of challenges that made it difficult to avoid sexual risks and protective beliefs and behaviors that facilitated avoidance of those risks. RESULTS: Participants reported yearning for connection, partners' desire to not use condoms, and judgmental caregivers as challenges. Protective beliefs and behaviors included open communication with their caregivers about SRH, abstinence, contraceptive use, and participants' desire to be healthy. CONCLUSIONS: Study findings shed light on protective beliefs and behaviors female youth in foster care used to safeguard themselves from negative SRH outcomes. Youth at times lacked agency in sexual decision-making and contraceptive use. PRACTICE IMPLICATIONS: Findings highlight the importance of sexual relationships and partner communication related to contraceptive use, and offering trauma-informed interventions, including culturally sensitive counseling regarding long acting reversible contraception.


Assuntos
Negro ou Afro-Americano , Infecções Sexualmente Transmissíveis , Adolescente , Adulto , Preservativos , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Comportamento Sexual , Infecções Sexualmente Transmissíveis/prevenção & controle , Virginia , Adulto Jovem
8.
Prostate ; 77(16): 1601-1608, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29030865

RESUMO

BACKGROUND: Understanding how biological factors contribute to prostate cancer (PCa) health disparities requires mechanistic functional analysis of specific genes or pathways in pre-clinical cellular and animal models of this malignancy. The 22Rv1 human prostatic carcinoma cell line was originally derived from the parental CWR22R cell line. Although 22Rv1 has been well characterized and used in numerous mechanistic studies, no racial identifier has ever been disclosed for this cell line. In accordance with the need for racial diversity in cancer biospecimens and recent guidelines by the NIH on authentication of key biological resources, we sought to determine the ancestry of 22RV1 and authenticate previously reported racial identifications for four other PCa cell lines. METHODS: We used 29 established Ancestry Informative Marker (AIM) single nucleotide polymorphisms (SNPs) to conduct DNA ancestry analysis and assign ancestral proportions to a panel of five PCa cell lines that included 22Rv1, PC3, DU145, MDA-PCa-2b, and RC-77T/E. RESULTS: We found that 22Rv1 carries mixed genetic ancestry. The main ancestry proportions for this cell line were 0.41 West African (AFR) and 0.42 European (EUR). In addition, we verified the previously reported racial identifications for PC3 (0.73 EUR), DU145 (0.63 EUR), MDA-PCa-2b (0.73 AFR), and RC-77T/E (0.74 AFR) cell lines. CONCLUSIONS: Considering the mortality disparities associated with PCa, which disproportionately affect African American men, there remains a burden on the scientific community to diversify the availability of biospecimens, including cell lines, for mechanistic studies on potential biological mediators of these disparities. This study is beneficial by identifying another PCa cell line that carries substantial AFR ancestry. This finding may also open the door to new perspectives on previously published studies using this cell line.


Assuntos
Biomarcadores Tumorais/genética , População Negra/genética , Disparidades em Assistência à Saúde , Polimorfismo de Nucleotídeo Único/genética , Neoplasias da Próstata/genética , População Branca/genética , Linhagem Celular Tumoral , Disparidades em Assistência à Saúde/tendências , Humanos , Masculino
9.
Electromagn Biol Med ; 36(1): 74-87, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27398987

RESUMO

Traumatic spinal cord injury (SCI) is typically the result of direct mechanical impact to the spine, leading to fracture and/or dislocation of the vertebrae along with damage to the surrounding soft tissues. Injury to the spinal cord results in disruption of axonal transmission of signals. This primary trauma causes secondary injuries that produce immunological responses such as neuroinflammation, which perpetuates neurodegeneration and cytotoxicity within the injured spinal cord. To date there is no FDA-approved pharmacological agent to prevent the development of secondary SCI and induce regenerative processes aimed at healing the spinal cord and restoring neurological function. An alternative method to electrically activate spinal circuits is the application of a noninvasive electromagnetic field (EMF) over intact vertebrae. The EMF method of modulating molecular signaling of inflammatory cells emitted in the extra-low frequency range of <100 Hz, and field strengths of <5 mT, has been reported to decrease inflammatory markers in macrophages, and increase endogenous mesenchymal stem cell (MSC) proliferation and differentiation rates. EMF has been reported to promote osteogenesis by improving the effects of osteogenic media, and increasing the proliferation of osteoblasts, while inhibiting osteoclast formation and increasing bone matrix in vitro. EMF has also been shown to increase chondrogenic markers and collagen and induce neural differentiation, while increasing cell viability by over 50%. As advances are made in stem cell technologies, stabilizing the cell line after differentiation is crucial to SCI repair. Once cell-seeded scaffolds are implanted, EMF may be applied outside the wound for potential continued adjunct treatment during recovery.


Assuntos
Magnetoterapia/métodos , Regeneração Nervosa/efeitos da radiação , Traumatismos da Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/terapia , Animais , Ensaios Clínicos como Assunto , Humanos , Magnetoterapia/efeitos adversos
10.
J Biol Chem ; 290(3): 1770-85, 2015 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-25451934

RESUMO

Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is an enzyme best known for its role in glycolysis. However, extra-glycolytic functions of GAPDH have been described, including regulation of protein expression via RNA binding. GAPDH binds to numerous adenine-uridine rich elements (AREs) from various mRNA 3'-untranslated regions in vitro and in vivo despite its lack of a canonical RNA binding motif. How GAPDH binds to these AREs is still unknown. Here we discovered that GAPDH binds with high affinity to the core ARE from tumor necrosis factor-α mRNA via a two-step binding mechanism. We demonstrate that a mutation at the GAPDH dimer interface impairs formation of the second RNA-GAPDH complex and leads to changes in the RNA structure. We investigated the effect of this interfacial mutation on GAPDH oligomerization by crystallography, small-angle x-ray scattering, nano-electrospray ionization native mass spectrometry, and hydrogen-deuterium exchange mass spectrometry. We show that the mutation does not significantly affect GAPDH tetramerization as previously proposed. Instead, the mutation promotes short-range and long-range dynamic changes in regions located at the dimer and tetramer interface and in the NAD(+) binding site. These dynamic changes are localized along the P axis of the GAPDH tetramer, suggesting that this region is important for RNA binding. Based on our results, we propose a model for sequential GAPDH binding to RNA via residues located at the dimer and tetramer interfaces.


Assuntos
Gliceraldeído-3-Fosfato Desidrogenases/química , RNA/química , Regiões 3' não Traduzidas , Motivos de Aminoácidos , Sequência de Aminoácidos , Anisotropia , Sítios de Ligação , DNA Complementar/metabolismo , Gliceraldeído-3-Fosfato Desidrogenases/genética , Glicólise , Humanos , Microscopia de Fluorescência , Dados de Sequência Molecular , Mutação , Peptídeos/química , Ligação Proteica , Conformação Proteica , Multimerização Proteica , Espalhamento de Radiação , Homologia de Sequência de Aminoácidos , Espectrometria de Massas por Ionização por Electrospray , Fator de Necrose Tumoral alfa/metabolismo , Raios X
11.
Altern Ther Health Med ; 22(3): 52-64, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27228272

RESUMO

Context • During cell-communication processes, endogenous and exogenous signaling affects normal and pathological developmental conditions. Exogenous influences, such as extra-low-frequency (ELF) electromagnetic fields (EMFs) have been shown to affect pain and inflammation by modulating G-protein coupling receptors (GPCRs), downregulating cyclooxygenase-2 (Cox-2) activity, and downregulating inflammatory modulators, such as tumor necrosis factor alpha (TNF-α) and interleukin 1 beta (IL-1ß) as well as the transcription factor nuclear factor kappa B (NF-κB). EMF devices could help clinicians who seek an alternative or complementary treatment for relief of patients chronic pain and disability. Objective • The research team intended to review the literature on the effects of EMFs on inflammatory pain mechanisms. Design • We used a literature search of articles published in PubMed using the following key words: low-frequency electromagnetic field therapy, inflammatory pain markers, cyclic adenosine monophosphate (cAMP), cyclic guanosine monophosphate (cGMP), opioid receptors, G-protein coupling receptors, and enzymes. Setting • The study took place at the Wake Forest School of Medicine in Winston-Salem, NC, USA. Results • The mechanistic pathway most often considered for the biological effects of EMF is the plasma membrane, across which the EMF signal induces a voltage change. Oscillating EMF exerts forces on free ions that are present on both sides of the plasma membrane and that move across the cell surface through transmembrane proteins. The ions create a forced intracellular vibration that is responsible for phenomena such as the influx of extracellular calcium (Ca2+) and the binding affinity of calmodulin (CaM), which is the primary transduction pathway to the secondary messengers, cAMP and cGMP, which have been found to influence inflammatory pain. Conclusions • An emerging body of evidence indicates the existence of a frequency-dependent interaction between the mechanical interventions of EMF and cell signaling along the peripheral inflammatory pain pathway.


Assuntos
Campos Eletromagnéticos , Inflamação , Nociceptividade , Dor/fisiopatologia , Membrana Celular , Citocinas/metabolismo , Humanos , NF-kappa B , Transdução de Sinais
12.
Electromagn Biol Med ; 35(3): 206-13, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26151161

RESUMO

During the cell communication process, endogenous and exogenous signaling affect normal as well as pathological developmental conditions. Exogenous influences such as extra-low-frequency electromagnetic field (EMF) have been shown to effect pain and inflammation by modulating G-protein receptors, down-regulating cyclooxygenase-2 activity, and affecting the calcium/calmodulin/nitric oxide pathway. Investigators have reported changes in opioid receptors and second messengers, such as cyclic adenosine monophosphate (cAMP), in opiate tolerance and dependence by showing how repeated exposure to morphine decreases adenylate cyclase activity causing cAMP to return to control levels in the tolerant state, and increase above control levels during withdrawal. Resonance responses to biological systems using exogenous EMF signals suggest that frequency response characteristics of the target can determine the EMF biological response. In our past research we found significant down regulation of inflammatory markers tumor necrosis factor alpha (TNF-α) and nuclear factor kappa B (NFκB) using 5 Hz EMF frequency. In this study cAMP was stimulated in Chinese Hamster Ovary (CHO) cells transfected with human mu-opioid receptors, then exposed to 5 Hz EMF, and outcomes were compared with morphine treatment. Results showed a 23% greater inhibition of cAMP-treating cells with EMF than with morphine. In order to test our results for frequency specific effects, we ran identical experiments using 13 Hz EMF, which produced results similar to controls. This study suggests the use of EMF as a complementary or alternative treatment to morphine that could both reduce pain and enhance patient quality of life without the side-effects of opiates.


Assuntos
AMP Cíclico/metabolismo , Campos Eletromagnéticos , Receptores Opioides mu/metabolismo , Animais , Células CHO , Colforsina/metabolismo , Cricetinae , Cricetulus , Espaço Extracelular/metabolismo , Espaço Extracelular/efeitos da radiação , Humanos , Espaço Intracelular/metabolismo , Espaço Intracelular/efeitos da radiação , Receptores Opioides mu/genética , Transdução de Sinais/efeitos da radiação , Regulação para Cima/efeitos da radiação
13.
Wound Repair Regen ; 23(6): 830-41, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26053405

RESUMO

Oxygen generating biomaterials represent a new trend in regenerative medicine that aims to generate and supply oxygen at the site of requirement, to support tissue healing and regeneration. To enhance the healing of dermal wounds, we have developed a highly portable, in situ oxygen generating wound dressings that uses sodium percarbonate (SPO) and calcium peroxide (CPO) as chemical oxygen sources. The dressing continuously generated oxygen for more than 3 days, after which it was replaced. In the in vivo testing on porcine full-thickness porcine wound model, the SPO/CPO dressing showed enhanced wound healing during the 8 week study period. Quantitative measurements of wound healing related parameters, such as wound closure, reepithelialization, epidermal thickness and collagen content of dermis showed that supplying oxygen topically using the SPO/CPO dressing significantly accelerated the wound healing. An increase in neovascularization, as determined using Von Willebrand factor (vWF) and CD31 staining, was also observed in the presence of SPO/CPO dressing. This novel design for a wound dressing that contains oxygen generating biomaterials (SPO/CPO) for supplying topical oxygen, may find utility in treating various types of acute to chronic wounds.


Assuntos
Bandagens , Oxigênio/farmacologia , Peróxidos/farmacologia , Regeneração , Lesões dos Tecidos Moles/patologia , Cicatrização , Administração Tópica , Animais , Materiais Biocompatíveis , Modelos Animais de Doenças , Neovascularização Fisiológica , Medicina Regenerativa , Suínos , Cicatrização/efeitos dos fármacos
14.
Bioorg Med Chem Lett ; 25(8): 1715-1717, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25791452

RESUMO

Halogenated thieno[3,2-d]pyrimidines exhibit antiproliferative activity against a variety of cancer cell models, such as the mouse lymphocytic leukemia cell line L1210 in which they induce apoptosis independent of cell cycle arrest. Here we assessed these activities on MDA-MB-231 cells, a well-established model of aggressive, metastatic breast cancer. While 2,4-dichloro[3,2-d]pyrimidine was less toxic to MDA-MB-231 cells than previously observed in the L1210 model, flow cytometry analysis showed that MDA-MB-231 cell death involved arrest at the G2/M stage of the cell cycle. Conversely, the introduction of bromine at C7 of the 2,4-dichloro[3,2-d]pyrimidine eliminated cell type-dependent differences in cytotoxicity or cell cycle status. Together, these data indicate that a substituent at C7 can profoundly modify the cytotoxic mechanism of halogenated thieno[3,2-d]pyrimidines in a cell type-specific manner.


Assuntos
Antineoplásicos/química , Brometos/química , Pirimidinas/química , Antineoplásicos/síntese química , Antineoplásicos/toxicidade , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Humanos , Pontos de Checagem da Fase M do Ciclo Celular/efeitos dos fármacos , Pirimidinas/síntese química , Pirimidinas/toxicidade
15.
Bioorg Med Chem ; 23(15): 4354-4363, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26122770

RESUMO

In vitro evaluation of the halogenated pyrrolo[3,2-d]pyrimidines identified antiproliferative activities in compounds 1 and 2 against four different cancer cell lines. Upon screening of a series of pyrrolo[3,2-d]pyrimidines, the 2,4-Cl compound 1 was found to exhibit antiproliferative activity at low micromolar concentrations. Introduction of iodine at C7 resulted in significant enhancement of potency by reducing the IC50 into sub-micromolar levels, thereby suggesting the importance of a halogen at C7. This finding was further supported by an increased antiproliferative effect for 4 as compared to 3. Cell-cycle and apoptosis studies conducted on the two potent compounds 1 and 2 showed differences in their cytotoxic mechanisms in triple negative breast cancer MDA-MB-231 cells, wherein compound 1 induced cells to accumulate at the G2/M stage with little evidence of apoptotic death. In contrast, compound 2 robustly induced apoptosis with concomitant G2/M cell cycle arrest in this cell model.


Assuntos
Antineoplásicos/química , Pirimidinas/química , Pirróis/química , Antineoplásicos/síntese química , Antineoplásicos/toxicidade , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Halogenação , Humanos , Pontos de Checagem da Fase M do Ciclo Celular/efeitos dos fármacos , Pirimidinas/síntese química , Pirimidinas/toxicidade , Pirróis/síntese química , Pirróis/toxicidade , Relação Estrutura-Atividade
16.
Bioorg Med Chem ; 22(7): 2113-22, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24631358

RESUMO

The in vitro evaluation of thieno[3,2-d]pyrimidines identified halogenated compounds 1 and 2 with antiproliferative activity against three different cancer cell lines. A structure activity relationship study indicated the necessity of the chlorine at the C4-position for biological activity. The two most active compounds 1 and 2 were found to induce apoptosis in the leukemia L1210 cell line. Additionally, the compounds were screened against a variety of other microbial targets and as a result, selective activity against several fungi was also observed. The synthesis and preliminary biological results are reported herein.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Antineoplásicos/farmacologia , Bacillus subtilis/efeitos dos fármacos , Fungos/efeitos dos fármacos , Pirimidinas/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Antifúngicos/síntese química , Antifúngicos/química , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Pirimidinas/síntese química , Pirimidinas/química , Relação Estrutura-Atividade , Células Tumorais Cultivadas
17.
Int Braz J Urol ; 40(6): 745-52, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25615243

RESUMO

OBJECTIVES: To evaluate the PSA in a large population of Brazilian men undergone to check up, and correlate the PSA cutoffs with prostate size and urinary symptoms. MATERIALS AND METHODS: This is a cross sectional study performed with men between 40 and 70 years undergone to check-up. All men were undergone to urological evaluation, digital rectal examination, prostate-specific antigen, and ultrasonography The exclusion criteria were men who used testosterone in the last six months, or who were using 5 alpha-reductase inhibitors. RESULTS: A total of 5015 men with an average age of 49.0 years completed the study. Most men were white and asymptomatic. The PSA in the three different aging groups were 0.9 ± 0.7 ng/dL for men between 40 and 50; 1.2 ± 0.5 ng/dL for men between 50 and 60; and 1.7 ± 1.5 ng/dL for men greater than 60 years (p=0.001). A total of 192 men had PSA between 2.5 and 4 ng/ml. From these men 130 were undergone to prostate biopsy. The predictive positive value of biopsy was 25% (32/130). In the same way, 100 patients had PSA > 4 ng/mL. From these men, 80 were undergone to prostate biopsy. In this group, the predictive positive value of biopsy was 40% (32/100). The Gleason score was 6 in 19 men (60%), 7 in 10 men (31%) and 8 in 3 men (9%). CONCLUSIONS: The PSA level of Brazilian men undergone to check up was low. There was a positive correlation with aging, IPSS and prostate size.


Assuntos
Detecção Precoce de Câncer/métodos , Antígeno Prostático Específico/sangue , Próstata/patologia , Neoplasias da Próstata/patologia , Adulto , Fatores Etários , Idoso , Análise de Variância , Biópsia , Brasil , Estudos Transversais , Exame Retal Digital , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Valor Preditivo dos Testes , Próstata/diagnóstico por imagem , Neoplasias da Próstata/sangue , Ultrassonografia
18.
bioRxiv ; 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38410477

RESUMO

Breast cancer is the most frequently diagnosed cancer worldwide, constituting around 15% of all diagnosed cancers in 2023. The predominant cause of breast cancer-related mortality is metastasis to distant essential organs, and a lack of metastasis-targeted therapies perpetuates dismal outcomes for late-stage patients. However, through our use of meiotic genetics to study inherited transcriptional network regulation, we have identified a new class of "Goldilocks" genes that are promising candidates for the development of metastasis-targeted therapeutics. Building upon previous work that implicated the CCR4-NOT RNA deadenylase complex in metastasis, we now demonstrate that the RNA-binding proteins (RNA-BPs) NANOS1, PUM2, and CPSF4 also regulate metastatic potential. Using cell lines, 3D culture, mouse models, and clinical data, we pinpoint Smarcd1 mRNA as a key target of all three RNA-BPs. Strikingly, both high and low expression of Smarcd1 is associated with positive clinical outcomes, while intermediate expression significantly reduces the probability of survival. Applying the theory of "essential genes" from evolution, we identify an additional 50 genes that span several cellular processes and must be maintained within a discrete window of expression for metastasis to occur. In the case of Smarcd1, small perturbations in its expression level significantly reduce metastasis in laboratory mouse models and alter splicing programs relevant to the ER+/HER2-enriched breast cancer subtype. The identification of subtype-specific "Goldilocks" metastasis modifier genes introduces a new class of genes and potential catalogue of novel targets that, when therapeutically "nudged" in either direction, may significantly improve late-stage patient outcomes.

19.
ArXiv ; 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38903746

RESUMO

Gene set knowledge discovery is essential for advancing human functional genomics. Recent studies have shown promising performance by harnessing the power of Large Language Models (LLMs) on this task. Nonetheless, their results are subject to several limitations common in LLMs such as hallucinations. In response, we present GeneAgent, a first-of-its-kind language agent featuring self-verification capability. It autonomously interacts with various biological databases and leverages relevant domain knowledge to improve accuracy and reduce hallucination occurrences. Benchmarking on 1,106 gene sets from different sources, GeneAgent consistently outperforms standard GPT-4 by a significant margin. Moreover, a detailed manual review confirms the effectiveness of the self-verification module in minimizing hallucinations and generating more reliable analytical narratives. To demonstrate its practical utility, we apply GeneAgent to seven novel gene sets derived from mouse B2905 melanoma cell lines, with expert evaluations showing that GeneAgent offers novel insights into gene functions and subsequently expedites knowledge discovery.

20.
J Am Geriatr Soc ; 72(7): 2120-2125, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38441308

RESUMO

BACKGROUND: Decisions regarding resuscitation after cardiac arrest are critical from ethical, patient satisfaction, outcome, and healthcare cost standpoints. Physician-reported discussion barriers include topic discomfort, fear of time commitment, and difficulty articulating end-of-life concepts. The influence of language used in these discussions has not been tested. This study explored whether utilizing the alternate term "allow (a) natural death" changed code status decisions in hospitalized patients versus "do not resuscitate" (DNR). METHODS: All patients age 65 and over admitted to a general medicine hospital teaching service were screened (English-speaking, not ICU-level care, no active psychiatric illness, no substance misuse, no active DNR). Participants were randomized to resuscitation discussions with either DNR or "allow natural death" as the "no code" phrasing. Outcomes included patient resuscitation decision, satisfaction with and duration of the conversation, and decision correlation with illness severity and predicted resuscitation success. RESULTS: 102 participants were randomized to the "allow natural death" (N = 49) or DNR (N = 53) arms. The overall "no code" rate for our sample of hospitalized general medicine inpatients age >65 was 16.7%, with 13% in the DNR and 20.4% in the "allow natural death" arms (p = 0.35). Discussion length was similar in the DNR and "allow natural death" arms (3.9 + 3.2 vs. 4.9 + 3.9 minutes), and not significantly different (p = 0.53). Over 90% of participants were highly satisfied with their code status decision, without difference between arms (p = 0.49). CONCLUSIONS: Participants' code status discussions did not differ in "no code" rate between "allow natural death" and DNR arms but were short in length and had high patient satisfaction. Previously reported code status discussion barriers were not encountered. It is appropriate to screen code status in all hospitalized patients regardless of phrasing used.


Assuntos
Parada Cardíaca , Ordens quanto à Conduta (Ética Médica) , Humanos , Masculino , Feminino , Ordens quanto à Conduta (Ética Médica)/ética , Ordens quanto à Conduta (Ética Médica)/psicologia , Idoso , Parada Cardíaca/terapia , Satisfação do Paciente , Idoso de 80 Anos ou mais , Tomada de Decisões/ética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA