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1.
Pathogens ; 11(11)2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36364994

RESUMO

The microbial ecosystem of the female urogenital tract is composed of many niche microenvironments across multiple organ systems in the urinary and reproductive tract. It is complex and contains a variety of bacteria, archaea, viruses, yeast, and protozoa-Many of which are still unidentified or whose functionality is unknown. Unlike the gut microbiome, whose composition is relatively stable in the absence of external perturbations, the urogenital microbiome is constantly shifting in response to biological cycles such as hormonal fluctuations during menstruation. Microbial composition differs between women but the dominance of some microbial families, such as Lactobacillaceae and other lactic acid-producing bacteria, are shared. Research suggests that it is difficult to define a universal healthy urogenital microbiome and consequently map a path to recovery from disease due to dysbiosis. Due to its temporal shifts, the female urogenital microbiome offers a unique opportunity to examine the biological mechanisms that work to restore a microbiome to its baseline. Common functional disorders in women's health are often difficult to diagnose and treat, are prone to recurrence, and can lead to subfertility or infertility. Knowledge of the interconnected microorganism communities along the continuum of the female reproductive tract could revolutionize the quality of women's healthcare.

2.
Exp Neurol ; 234(1): 161-8, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22226594

RESUMO

Severe traumatic brain injury (TBI) is associated with a high incidence of acute mortality followed by chronic alteration of homeostatic network activity that includes the emergence of posttraumatic seizures. We hypothesized that acute and chronic outcome after severe TBI critically depends on disrupted bioenergetic network homeostasis, which is governed by the availability of the brain's endogenous neuroprotectant adenosine. We used a rat lateral fluid percussion injury (FPI) model of severe TBI with an acute mortality rate of 46.7%. A subset of rats was treated with 25mg/kg caffeine intraperitoneally within 1 min of the injury. We assessed neuromotor function at 24h and 4 weeks, and video-EEG activity and histology at 4 weeks following injury. We first demonstrate that acute mortality is related to prolonged apnea and that a single acute injection of the adenosine receptor antagonist caffeine can completely prevent TBI-induced mortality when given immediately following the TBI. Second, we demonstrate that neuromotor function is not affected by caffeine treatment at either 24h or 4 weeks following injury. Third, we demonstrate development of epileptiform EEG bursts as early as 4 weeks post-injury that are significantly reduced in duration in the rats that received caffeine. Our data demonstrate that acute treatment with caffeine can prevent lethal apnea following fluid percussion injury, with no negative influence on motor function or histological outcome. Further, we show epileptiform bursting is reduced after caffeine treatment, suggesting a potential role in the modulation of epilepsy development after severe injury.


Assuntos
Lesões Encefálicas/tratamento farmacológico , Lesões Encefálicas/mortalidade , Cafeína/uso terapêutico , Estimulantes do Sistema Nervoso Central/uso terapêutico , Animais , Lesões Encefálicas/fisiopatologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Eletroencefalografia , Epilepsia/etiologia , Epilepsia/prevenção & controle , Potenciais Evocados/efeitos dos fármacos , Comportamento Exploratório/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
3.
J Control Release ; 144(2): 159-67, 2010 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-20138938

RESUMO

Due to its unique properties, silk fibroin was studied as a biodegradable polymer vehicle for sustained, local delivery of the anticonvulsant adenosine from encapsulated reservoirs. Silk is a biologically derived protein polymer that is biocompatible, mechanically strong and degrades to non-toxic products in vivo. To achieve local, sustained, controlled adenosine release from fully degradable implants, solid adenosine powder reservoirs were coated with silk fibroin. Material properties of the silk coating including thickness, crystallinity and morphology were investigated to assess the relationships between silk coating biomaterial features and adenosine release from silk encapsulated reservoirs. Reservoir coating thickness was varied through manipulation of the silk coating solution concentration and number of coatings applied. Release studies were also performed in proteinase type XIV to model the effects of degradation. Increasing the barrier to diffusion, either by increasing coating thickness or crystallinity was found to delay adenosine burst, decrease average daily release rate, and increase duration of release. In the case of encapsulated reservoirs coated with eight layers of 8% (w/v) silk, a linear release profile was observed and adenosine release was sustained for 14days. The ability to achieve nearly constant release for 2weeks for adenosine via control of the silk coating suggests these encapsulated reservoirs represent a novel system for delivering adenosine. We anticipate that this approach could also be extended to other implant needs and small-molecule drugs to treat a range of clinical needs.


Assuntos
Adenosina/uso terapêutico , Fibroínas/química , Animais , Materiais Biocompatíveis/uso terapêutico , Difusão , Polímeros/química , Pós , Próteses e Implantes , Proteínas/metabolismo , Seda
4.
J Diabetes Sci Technol ; 4(6): 1311-21, 2010 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-21129325

RESUMO

BACKGROUND: For automated prevention of hypoglycemia, there is a need for glucagon (or an analog) to be sufficiently stable so that it can be indwelled in a portable pump for at least 3 days. However, under some conditions, solutions of glucagon can form amyloid fibrils. Currently, the usage instructions for commercially available glucagon allow only for its immediate use. METHODS: In NIH 3T3 fibroblasts, we tested amyloid formation and cytotoxicity of solutions of native glucagon and the glucagon analog MAR-D28 after aging under different conditions for 5 days. In addition, aged native glucagon was subjected to size-exclusion chromatography (SEC). We also studied whether subcutaneous aged Novo Nordisk GlucaGen® would have normal bioactivity in octreotide-treated, anesthetized, nondiabetic pigs. RESULTS: We found no evidence of cytotoxicity from native glucagon or MAR-D28 (up to 2.5 mg/ml) at a pH of 10 in a glycine solvent. We found a mild cytotoxicity for both compounds in Tris buffer at pH 8.5. A high concentration of the commercial glucagon preparation (GlucaGen) caused marked cytotoxicity, but low pH and/or a high osmolarity probably accounted primarily for this effect. With SEC, the decline in monomeric glucagon over time was much lower when aged in glycine (pH 10) than when aged in Tris (pH 8.5) or in citrate (pH 3). Congo red staining for amyloid was very low with the glycine preparation (pH 10). In the pig studies, the hyperglycemic effect of commercially available glucagon was preserved despite aging conditions associated with marked amyloid formation. CONCLUSIONS: Under certain conditions, aqueous solutions of glucagon and MAR-D28 are stable for at least 5 days and are thus very likely to be safe in mammals. Glycine buffer at a pH of 10 appears to be optimal for avoiding cytotoxicity and amyloid fibril formation.


Assuntos
Glicemia/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Glucagon/farmacologia , Amiloide/química , Animais , Glicemia/metabolismo , Soluções Tampão , Sobrevivência Celular/efeitos dos fármacos , Química Farmacêutica , Cromatografia em Gel , Relação Dose-Resposta a Droga , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Glucagon/administração & dosagem , Glucagon/análogos & derivados , Glucagon/química , Glucagon/toxicidade , Concentração de Íons de Hidrogênio , Injeções Subcutâneas , Camundongos , Células NIH 3T3 , Octreotida/farmacologia , Concentração Osmolar , Suínos , Fatores de Tempo
5.
Exp Neurol ; 219(1): 126-35, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19460372

RESUMO

Pharmacotherapy for epilepsy is limited by high incidence of pharmacoresistance and failure to prevent development and progression of epilepsy. Using the rat hippocampal kindling model, we report on the therapeutic potential of novel silk-based polymers engineered to release the anticonvulsant adenosine. Polymers were designed to release 1000 ng adenosine per day during a time span of ten days. In the first experiment rats were kindled by hippocampal electrical stimulation until all animals reacted with stage 5 seizures. Adenosine-releasing or control polymers were then implanted into the infrahippocampal fissure ipsilateral to the site of stimulation. Subsequently, only recipients of adenosine-releasing implants were completely protected from generalized seizures over a period of ten days corresponding to the duration of sustained adenosine release. To monitor seizure development in the presence of adenosine, adenosine-releasing or control polymers were implanted prior to kindling. After 30 stimulations--delivered from days 4 to 8 after implantation--control animals had developed convulsive stage 5 seizures, whereas recipients of adenosine-releasing implants were still protected from convulsive seizures. Kindling was resumed after nine days to allow expiration of adenosine release. During additional 30 stimulations, recipients of adenosine-releasing implants gradually resumed kindling development at seizure stages corresponding to those when kindling was initially suspended, while control rats resumed kindling development at convulsive seizure stages. Blockade of adenosine A1 receptors did not exacerbate seizures in protected animals. We conclude that silk-based adenosine delivery exerts potent anti-ictogenic effects, but might also have at least partial anti-epileptogenic effects. Thus, silk-based adenosine augmentation holds promise for the treatment of epilepsy.


Assuntos
Adenosina/farmacologia , Anticonvulsivantes/farmacologia , Epilepsia/tratamento farmacológico , Excitação Neurológica/efeitos dos fármacos , Polímeros/uso terapêutico , Seda/uso terapêutico , Adenosina/metabolismo , Adenosina/uso terapêutico , Antagonistas do Receptor A1 de Adenosina , Animais , Anticonvulsivantes/metabolismo , Anticonvulsivantes/uso terapêutico , Modelos Animais de Doenças , Sistemas de Liberação de Medicamentos/métodos , Implantes de Medicamento/farmacologia , Estimulação Elétrica , Epilepsia/etiologia , Epilepsia/fisiopatologia , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Hipocampo/fisiopatologia , Excitação Neurológica/fisiologia , Masculino , Ratos , Ratos Sprague-Dawley , Receptor A1 de Adenosina/metabolismo , Convulsões/tratamento farmacológico , Convulsões/etiologia , Convulsões/fisiopatologia , Resultado do Tratamento
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