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1.
Nature ; 440(7084): 692-6, 2006 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-16572175

RESUMO

Bone metastases are a frequent complication of many cancers that result in severe disease burden and pain. Since the late nineteenth century, it has been thought that the microenvironment of the local host tissue actively participates in the propensity of certain cancers to metastasize to specific organs, and that bone provides an especially fertile 'soil'. In the case of breast cancers, the local chemokine milieu is now emerging as an explanation for why these tumours preferentially metastasize to certain organs. However, as the inhibition of chemokine receptors in vivo only partially blocks metastatic behaviour, other factors must exist that regulate the preferential metastasis of breast cancer cells. Here we show that the cytokine RANKL (receptor activator of NF-kappaB ligand) triggers migration of human epithelial cancer cells and melanoma cells that express the receptor RANK. RANK is expressed on cancer cell lines and breast cancer cells in patients. In a mouse model of melanoma metastasis, in vivo neutralization of RANKL by osteoprotegerin results in complete protection from paralysis and a marked reduction in tumour burden in bones but not in other organs. Our data show that local differentiation factors such as RANKL have an important role in cell migration and the tissue-specific metastatic behaviour of cancer cells.


Assuntos
Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/secundário , Proteínas de Transporte/metabolismo , Movimento Celular , Glicoproteínas de Membrana/metabolismo , Metástase Neoplásica/patologia , Animais , Neoplasias Ósseas/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proteínas de Transporte/genética , Morte Celular , Diferenciação Celular , Linhagem Celular Tumoral , Proliferação de Células , Células Epiteliais/patologia , Feminino , Humanos , Melanoma/metabolismo , Melanoma/patologia , Glicoproteínas de Membrana/genética , Camundongos , Especificidade de Órgãos , Paralisia , Ligante RANK , Receptor Ativador de Fator Nuclear kappa-B , Transdução de Sinais
2.
Reprod Toxicol ; 26(2): 175-7, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18640262

RESUMO

BACKGROUND: Use of HMG-CoA reductase inhibitors (statins) is becoming increasingly common. However, a recent study based on a series of cases reported to FDA suggests possible teratogenic effects of statins on embryogenesis, such as limb defects and severe central nervous system anomalies. METHODS: In a prospective, observational cohort study with a comparison group to examine a fetal toxicity risk of statins, we followed 64 pregnant women taking statins, and 64 comparison group women without exposure to known teratogens. The statin group women were exposed to atorvastatin (n=46), simvastatin (n=9), pravastatin (n=6), or rosuvastatin (n=3) during the first trimester. RESULTS: There was no difference in the rate of major malformations between the statin group (1/46 live birth: 2.2%) and the comparison group (1/52 live birth: 1.9%, p=0.93). Similarly, there were no statistical differences between the statin and comparison groups in live births (71.9% vs 81.2%), spontaneous abortions (14: 21.9% vs 11: 17.2%), therapeutic abortions (3: 4.7% vs 0: 0%) and stillbirths (1: 1.5% vs 1: 1.6%). Gestational age at birth (38.4+/-2.8 weeks vs 39.3+/-1.3 weeks: M+/-S.D., p=0.04) and birth weight (3.14+/-0.68kg vs 3.45+/-0.42kg, p=0.01) were lower in the statin group. CONCLUSIONS: The absolute risk of teratogenicity of statins, if any, appears relatively small. A large-scale study is needed to further characterize the teratogenic potential.


Assuntos
Desenvolvimento Fetal/efeitos dos fármacos , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Resultado da Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Anormalidades Induzidas por Medicamentos/epidemiologia , Anormalidades Induzidas por Medicamentos/etiologia , Peso ao Nascer/efeitos dos fármacos , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Idade Gestacional , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Recém-Nascido , Gravidez , Resultado da Gravidez/epidemiologia , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Estudos Prospectivos
3.
Mol Cell Biol ; 23(21): 7708-18, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14560016

RESUMO

Cbl family proteins are evolutionarily conserved ubiquitin ligases that negatively regulate signaling from tyrosine kinase-coupled receptors. The mammalian cbl family consists of c-Cbl, Cbl-b, and the recently cloned Cbl-3 (also known as Cbl-c). In this study, we describe the detailed expression pattern of murine Cbl-3 and report the generation and characterization of Cbl-3-deficient mice. Cbl-3 exhibits an expression pattern distinct from those of c-Cbl and Cbl-b, with high levels of Cbl-3 expression in epithelial cells of the gastrointestinal tract and epidermis, as well as the respiratory, urinary, and reproductive systems. Cbl-3 expression was not detected in nonepithelial cells, but within epithelial tissues, the levels of Cbl-3 expression varied from undetectable in the alveoli of the lungs to very strong in the cecum and colon. Despite this restricted expression pattern, Cbl-3-deficient mice were viable, healthy, and fertile and displayed no histological abnormalities up to 18 months of age. Proliferation of epithelial cells in the epidermises and gastrointestinal tracts was unaffected by the loss of Cbl-3. Moreover, Cbl-3 was not required for attenuation of epidermal growth factor-stimulated Erk activation in primary keratinocytes. Thus, Cbl-3 is dispensable for normal epithelial development and function.


Assuntos
Células Epiteliais/metabolismo , Epitélio/crescimento & desenvolvimento , Proteínas Oncogênicas de Retroviridae/metabolismo , Animais , Células Cultivadas , Ativação Enzimática , Células Epiteliais/citologia , Epitélio/anatomia & histologia , Regulação da Expressão Gênica , Marcação de Genes , Humanos , Hibridização In Situ , Queratinócitos/citologia , Queratinócitos/metabolismo , Camundongos , Camundongos Knockout , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteínas Proto-Oncogênicas c-cbl , Proteínas Oncogênicas de Retroviridae/genética , Distribuição Tecidual
4.
J Med Food ; 16(12): 1079-85, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24328700

RESUMO

Clostridium difficile is the leading cause of hospital-acquired antibiotic-associated diarrhea worldwide; in addition, the proliferation of antibiotic-resistant C. difficile is becoming a significant problem. Virgin coconut oil (VCO) has been shown previously to have the antimicrobial activity. This study evaluates the lipid components of VCO for the control of C. difficile. VCO and its most active individual fatty acids were tested to evaluate their antimicrobial effect on C. difficile in vitro. The data indicate that exposure to lauric acid (C12) was the most inhibitory to growth (P<.001), as determined by a reduction in colony-forming units per milliliter. Capric acid (C10) and caprylic acid (C8) were inhibitory to growth, but to a lesser degree. VCO did not inhibit the growth of C. difficile; however, growth was inhibited when bacterial cells were exposed to 0.15-1.2% lipolyzed coconut oil. Transmission electron microscopy (TEM) showed the disruption of both the cell membrane and the cytoplasm of cells exposed to 2 mg/mL of lauric acid. Changes in bacterial cell membrane integrity were additionally confirmed for VCO and select fatty acids using Live/Dead staining. This study demonstrates the growth inhibition of C. difficile mediated by medium-chain fatty acids derived from VCO.


Assuntos
Antibacterianos/farmacologia , Clostridioides difficile/efeitos dos fármacos , Ácidos Graxos/farmacologia , Óleos de Plantas/farmacologia , Caprilatos/farmacologia , Óleo de Coco , Contagem de Colônia Microbiana , Ácidos Decanoicos/farmacologia , Farmacorresistência Bacteriana , Ácidos Graxos/análise , Ácidos Láuricos/farmacologia , Metronidazol/farmacologia , Viabilidade Microbiana/efeitos dos fármacos , Microscopia Eletrônica de Transmissão , Óleos de Plantas/análise
5.
Rev Soc Bras Med Trop ; 44(2): 254-6, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21552747

RESUMO

This is a case report of a Brazilian soldier with cutaneous leishmaniasis. The lesion relapsed following two systemic treatments with meglumine antimoniate. The patient was treated with amphotericin B, which was interrupted due to poor tolerance. Following isolation of Leishmania sp., six intralesional infiltrations of meglumine antimoniate resulted in no response. Leishmania sp promastigotes were again isolated. The patient was submitted to intramuscular 4 mg/kg pentamidine. Parasites from the first and second biopsies were identified as Leishmania (Viannia) braziliensis; those isolated from the first biopsy were more sensitive to meglumine antimoniate in vitro than those isolated from the second biopsy. No relapse was observed.


Assuntos
Antiprotozoários/uso terapêutico , Leishmania braziliensis/efeitos dos fármacos , Leishmaniose Cutânea/parasitologia , Meglumina/uso terapêutico , Compostos Organometálicos/uso terapêutico , Pentamidina/uso terapêutico , Adulto , Humanos , Leishmaniose Cutânea/tratamento farmacológico , Masculino , Antimoniato de Meglumina , Testes de Sensibilidade Parasitária , Resultado do Tratamento
6.
Rev. Soc. Bras. Med. Trop ; 44(2): 254-256, Mar.-Apr. 2011. ilus
Artigo em Inglês | LILACS | ID: lil-586093

RESUMO

Relatamos um caso de um militar brasileiro com leishmaniose cutânea, cuja lesão reativou após dois tratamentos sistêmicos com antimoniato de meglumina. Foi tratado com anfotericina B, mas precisou interromper por intolerância à medicação. Após isolamento de Leishmania sp, seis infiltrações intralesionais de antimoniato de meglumina foram realizadas, sem resposta. Promastigotas de Leishmania sp. foram novamente isoladas. Foi submetido a tratamento intramuscular com pentamidina (4mg/kg). Parasitas da primeira e segunda biópsias foram identificados como Leishmania (Viannia) braziliensis; os da primeira biópsia eram mais sensíveis ao antimoniato de meglumina in vitro do que os da segunda biópsia. A lesão não reativou.


This is a case report of a Brazilian soldier with cutaneous leishmaniasis. The lesion relapsed following two systemic treatments with meglumine antimoniate. The patient was treated with amphotericin B, which was interrupted due to poor tolerance. Following isolation of Leishmania sp., six intralesional infiltrations of meglumine antimoniate resulted in no response. Leishmania sp promastigotes were again isolated. The patient was submitted to intramuscular 4mg/kg pentamidine. Parasites from the first and second biopsies were identified as Leishmania (Viannia) braziliensis; those isolated from the first biopsy were more sensitive to meglumine antimoniate in vitro than those isolated from the second biopsy. No relapse was observed.


Assuntos
Adulto , Humanos , Masculino , Antiprotozoários/uso terapêutico , Leishmania braziliensis/efeitos dos fármacos , Leishmaniose Cutânea/parasitologia , Meglumina/uso terapêutico , Compostos Organometálicos/uso terapêutico , Pentamidina/uso terapêutico , Leishmaniose Cutânea/tratamento farmacológico , Testes de Sensibilidade Parasitária , Resultado do Tratamento
7.
Can J Clin Pharmacol ; 11(2): e257-66, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15591613

RESUMO

BACKGROUND: Breastfeeding is the ideal method of infant nutrition. However, if mothers need medications such as the central nervous system (CNS) acting drugs, infant safety concerns arise. Summarized information on infant exposure levels to drugs in milk and associated side effect profiles will help clinicians to rationalize and justify important drug therapy for a breastfeeding patient. METHODS: Electronic searches of MEDLINE and PsycINFO from 1966-2003, and of EMBASE from 1980-2003, were conducted for studies on breastfeeding or breast milk and medications in the following categories: antidepressants, antipsychotics, antiepileptics (or anticonvulsants) and anxiolytics. The infant exposure level (%) was defined as follows: [Drug concentration in milk (mg/mL)] x [Daily milk intake (mL/kg/d)] x 100 / Maternal dose (mg/kg/d). RESULTS: A total of 129 papers were eligible for analyses. Our findings indicate that the majority of the CNS-acting drugs, if taken by nursing women, result in average exposure levels to their breast-fed infants of less than 10% of the therapeutic doses per kg body weight. Exceptions are lithium, ethosuximide, phenobarbital, primidone, lamotrigine and topiramate. Adverse effect profiles do not always correlate with a higher exposure level. Overall, most reported adverse effect profiles appear benign. Where adverse effects were reported, they were often confounded by intrauterine exposure. CONCLUSIONS: CNS-acting drugs taken by the mother do not appear to pose any major risks of immediate adverse effects to the breastfeeding infant, although with most of the newer drugs further research is needed to be conclusive.


Assuntos
Aleitamento Materno , Fármacos do Sistema Nervoso Central/efeitos adversos , Fármacos do Sistema Nervoso Central/farmacocinética , Leite Humano/metabolismo , Anticonvulsivantes/administração & dosagem , Anticonvulsivantes/efeitos adversos , Anticonvulsivantes/farmacocinética , Antidepressivos/administração & dosagem , Antidepressivos/efeitos adversos , Antidepressivos/farmacocinética , Antipsicóticos/administração & dosagem , Antipsicóticos/efeitos adversos , Antipsicóticos/farmacocinética , Fármacos do Sistema Nervoso Central/administração & dosagem , Feminino , Humanos , Lactente , Recém-Nascido
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