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1.
Artigo em Inglês | MEDLINE | ID: mdl-38265460

RESUMO

Premature ovarian insufficiency (POI) is one of many potential long-term consequences of childhood cancer treatment in females. Causes of POI in this patient population can include chemotherapy, especially alkylating agents, and radiation therapy. Rarely, ovarian tumors lead to ovarian dysfunction. POI can manifest as delayed pubertal development, irregular menses or amenorrhea, and infertility. This diagnosis often negatively impacts emotional health due to the implications of impaired ovarian function after already enduring treatment for a primary malignancy. The emerging adult may be challenged by the impact on energy level, quality of life, and fertility potential. POI can also lead to low bone density and compromised skeletal strength. This review discusses the health consequences of POI in childhood cancer survivors (CCS). We also explore the role of fertility preservation for CCS, including ovarian tissue cryopreservation and other available options. Lastly, knowledge gaps are identified that will drive a future research agenda.

2.
Bone ; 178: 116930, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37844715

RESUMO

PURPOSE: To investigate the skeletal phenotype of adolescent girls with premature ovarian insufficiency (POI). METHODS: Data are presented from two adolescent girls who participated in a clinical research protocol to evaluate axial bone mineral density (BMD) (via dual-energy x-ray absorptiometry, DXA) and appendicular bone density, microarchitecture, and strength (via high-resolution peripheral quantitative computed tomography, HRpQCT). Anthropometric data were also obtained, and pubertal staging was performed by a clinician. RESULTS: Both cases presented with an undetectable estradiol concentration and an elevated follicle stimulating hormone (FSH), meeting the criteria for POI. Each also received alkylating agents as part of their chemotherapy and radiotherapy, but in different locations as one presented with stage IV neuroblastoma and the other, metastatic medulloblastoma. Both had a low BMD of the axial and appendicular skeleton, as well as microarchitectural changes of the latter. The low BMD Z-score (<-2.0) seen when interpreting their DXA measurements for chronological age improved when adjusted for short stature, but it was not normalized. Lastly, most variables obtained by HRpQCT were abnormal for each participant, indicating that appendicular bone structure and strength were compromised. CONCLUSIONS: Chemotherapy and radiation affect growth, puberty, and bone accrual deleteriously. However, as these cases show, POI in an adolescent is not always classic primary ovarian insufficiency. Adolescents with brain cancer can present with signs of estrogen deficiency but may not be able to secrete FSH to the extent of elevation typically seen in long-term cancer survivors. Estrogen deficiency is almost universally present in either clinical setting and prompt recognition facilitates early provision of hormone replacement therapy that may then allow for a resumption of bone accrual as an adolescent approaches her peak bone mass.


Assuntos
Sobreviventes de Câncer , Hipogonadismo , Neoplasias , Insuficiência Ovariana Primária , Humanos , Adolescente , Feminino , Densidade Óssea , Insuficiência Ovariana Primária/complicações , Insuficiência Ovariana Primária/diagnóstico , Absorciometria de Fóton , Hormônio Foliculoestimulante , Estrogênios
3.
Int J Mol Sci ; 24(3)2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36768176

RESUMO

The opportunistic fungus Aspergillus fumigatus causes a set of diseases ranging from allergy to lethal invasive mycosis. Within the human airways, A. fumigatus is embedded in a biofilm that forms not only a barrier against the host immune defense system, but also creates a physical barrier protecting the fungi from chemicals such as antifungal drugs. Novel therapeutic strategies aim at combining drugs that inhibit biofilm synthesis or disrupt existing biofilm with classical antimicrobials. One of the major constituents of A. fumigatus biofilm is the polysaccharide galactosaminogalactan (GAG) composed of α1,4-linked N-acetylgalactosamine, galactosamine, and galactose residues. GAG is synthesized on the cytosolic face of the plasma membrane and is extruded in the extracellular space, where it is partially deacetylated. The deacetylase Agd3 that mediates this last step is essential for the biofilm formation and full virulence of the fungus. In this work, a previously described enzyme-linked lectin assay, based on the adhesion of deacetylated GAG to negatively charged plates and quantification with biotinylated soybean agglutinin was adapted to screen microbial natural compounds, as well as compounds identified in in silico screening of drug libraries. Actinomycin X2, actinomycin D, rifaximin, and imatinib were shown to inhibit Agd3 activity in vitro. At a concentration of 100 µM, actinomycin D and imatinib showed a clear reduction in the biofilm biomass without affecting the fungal growth. Finally, imatinib reduced the virulence of A. fumigatus in a Galleria mellonella infection model in an Agd3-dependent manner.


Assuntos
Aspergillus fumigatus , Polissacarídeos , Humanos , Dactinomicina , Mesilato de Imatinib , Polissacarídeos/metabolismo , Aspergillus fumigatus/metabolismo , Biofilmes
4.
Cells ; 8(11)2019 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-31671548

RESUMO

Invasive fungal infections (IFI) are an increasing threat to the developing world, with fungal spores being ubiquitous and inhaled every day. Some fungal species are commensal organisms that are part of the normal human microbiota, and, as such, do not pose a threat to the immune system. However, when the natural balance of this association is disturbed or the host's immune system is compromised, these fungal pathogens overtake the organism, and cause IFI. To understand the invasiveness of these pathogens and to address the growing problem of IFI, it is essential to identify the cellular processes of the invading organism and their virulence. In this review, we will discuss the prevalence and current options available to treat IFI, including recent reports of drug resistance. Nevertheless, the main focus of this review is to describe the glycobiology of human fungal pathogens and how various components of the fungal cell wall, particularly cell wall polysaccharides and glycoconjugates, are involved in fungal pathogenicity, their biosynthesis and how they can be potentially exploited to develop novel antifungal treatment options. We will specifically describe the nucleotide sugar transporters (NSTs) that are important in fungal survival and suggest that the inhibition of fungal NSTs may potentially be useful to prevent the establishment of fungal infections.


Assuntos
Antifúngicos/farmacologia , Parede Celular/química , Desenvolvimento de Medicamentos , Polissacarídeos Fúngicos/metabolismo , Fungos/efeitos dos fármacos , Glicômica , Infecções Fúngicas Invasivas/tratamento farmacológico , Fungos/metabolismo , Humanos , Infecções Fúngicas Invasivas/metabolismo , Infecções Fúngicas Invasivas/microbiologia
5.
Hum Resour Health ; 17(1): 57, 2019 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-31311561

RESUMO

BACKGROUND: Elevated blood pressure is the leading risk for mortality in the world. Task redistribution has been shown to be efficacious for hypertension management in low- and middle-income countries. However, the workforce requirements for such a task redistribution strategy are largely unknown. Therefore, we developed a needs-based workforce estimation model for hypertension management in western Kenya, using need and capacity as inputs. METHODS: Key informant interviews, focus group discussions, a Delphi exercise, and time-motion studies were conducted among administrative leadership, clinicians, patients, community leaders, and experts in hypertension management. These results were triangulated to generate the best estimates for the inputs into the health workforce model. The local hypertension clinical protocol was used to derive a schedule of encounters with different levels of clinician and health facility staff. A Microsoft Excel-based spreadsheet was developed to enter the inputs and generate the full-time equivalent workforce requirement estimates over 3 years. RESULTS: Two different scenarios were modeled: (1) "ramp-up" (increasing growth of patients each year) and (2) "steady state" (constant rate of patient enrollment each month). The ramp-up scenario estimated cumulative enrollment of 7000 patients by year 3, and an average clinical encounter time of 8.9 min, yielding nurse full-time equivalent requirements of 4.8, 13.5, and 30.2 in years 1, 2, and 3, respectively. In contrast, the steady-state scenario assumed a constant monthly enrollment of 100 patients and yielded nurse full-time equivalent requirements of 5.8, 10.5, and 14.3 over the same time period. CONCLUSIONS: A needs-based workforce estimation model yielded health worker full-time equivalent estimates required for hypertension management in western Kenya. The model is able to provide workforce projections that are useful for program planning, human resource allocation, and policy formulation. This approach can serve as a benchmark for chronic disease management programs in low-resource settings worldwide.


Assuntos
Necessidades e Demandas de Serviços de Saúde , Mão de Obra em Saúde , Hipertensão/terapia , Coleta de Dados/métodos , Feminino , Humanos , Hipertensão/epidemiologia , Quênia/epidemiologia , Masculino , População Rural
6.
Anat Rec (Hoboken) ; 299(5): 613-29, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26910848

RESUMO

Type V collagen (COLV) is a regulatory fibril-forming collagen. It has at least three different molecular isoforms-α1(V)2 α2(V), α1(V)3, and α1(V)α2(V)α3(V)-formed by combinations of three different polypeptide α chains-α1(V), α2(V), and α3(V). COL V is a relatively minor collagen of the extracellular matrix (ECM). Morphologically, COLV occurs as heterotypic fibrils with type I collagen (COLI), microfilaments, or 12-nm-thick fibrils. COLV is synthesized in various mesenchymal cells and its gene expression is modulated by TGF-ß and growth factors. While resistant to digestion by interstitial collagenases, native and denatured COLV are degraded by metalloproteinases and gelatinases, thereby promoting ECM remodeling. COLV interacts with matrix collagens and structural proteins, conferring structural integrity to tissue scaffolds. It binds matrix macromolecules, modulating cellular behavior, and functions. COLV co-assembles with COLI into heterotypic fibrils in the cornea and skin dermis, acting as a dominant regulator of collagen fibrillogenesis. COLV deficiency is associated with loss of corneal transparency and classic Ehlers-Danlos syndrome, while COLV overexpression is found in cancer, granulation tissue, inflammation, atherosclerosis, and fibrosis of lungs, skin, kidneys, adipose tissue, and liver. COLV isoform containing the α3(V) chain is involved in mediating pancreatic islet cell functions. In the liver, COLV is a minor but regular component of the ECM. Increases in COLV are associated with both early and advanced hepatic fibrosis. The neoepitopes of COLV have been shown to be a useful noninvasive serum biomarker for assessing fibrotic progression and resolution in experimental hepatic fibrosis. COLV is multifunctional in health, disease, and fibrosis.


Assuntos
Colágeno Tipo V/metabolismo , Doença , Matriz Extracelular/metabolismo , Fibrose/patologia , Fibrose/metabolismo , Humanos
7.
J Pharm Pharm Sci ; 17(2): 207-19, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24934549

RESUMO

PURPOSE: To evaluate the influence of co-administered vehicles on in vitro dissolution in simulated gastric fluid of crushed immediate release tablets as an indicator for potential drug bioavailability compromise. METHODS: Release and dissolution of crushed amlodipine, atenolol, carbamazepine and warfarin tablets were tested with six foods and drinks that are frequently used in the clinical setting as mixers for crushed medications (water, orange juice, honey, yoghurt, strawberry jam and water thickened with Easythick powder) in comparison to whole tablets. Five commercial thickening agents (Easythick Advanced, Janbak F, Karicare, Nutilis, Viscaid) at three thickness levels were tested for their effect on the dissolution of crushed atenolol tablets. RESULTS: Atenolol dissolution was unaffected by mixing crushed tablets with thin fluids or food mixers in comparison to whole tablets or crushed tablets in water, but amlodipine was delayed by mixing with jam. Mixing crushed warfarin and carbamazepine tablets with honey, jam or yoghurt caused them to resemble the slow dissolution of whole tablets rather than the faster dissolution of crushed tablets in water or orange juice. Crushing and mixing any of the four medications with thickened water caused a significant delay in dissolution. When tested with atenolol, all types of thickening agents at the greatest thickness significantly restricted dissolution, and products that are primarily based on xanthan gum also delayed dissolution at the intermediate thickness level. CONCLUSIONS: Dissolution testing, while simplistic, is a widely used and accepted method for comparing drug release from different formulations as an indicator for in vivo bioavailability. Thickened fluids have the potential to retard drug dissolution when used at the thickest levels. These findings highlight potential clinical implications of the addition of these agents to medications for the purpose of dose delivery and indicate that further investigation of thickened fluids and their potential to influence therapeutic outcomes is warranted.


Assuntos
Bebidas , Deglutição , Liberação Controlada de Fármacos , Alimentos , Preparações Farmacêuticas/administração & dosagem , Administração Oral , Disponibilidade Biológica , Deglutição/efeitos dos fármacos , Ingestão de Líquidos , Ingestão de Alimentos , Suco Gástrico/química , Humanos , Preparações Farmacêuticas/química , Comprimidos/administração & dosagem , Comprimidos/química
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