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1.
Mycology ; 15(1): 70-84, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38558844

RESUMO

In India, the incidence of mucormycosis reached high levels during 2021-2022, coinciding with the COVID-19 pandemic. In response to this, we established a multicentric ambispective cohort of patients hospitalised with mucormycosis across India. In this paper, we report their baseline profile, clinical characteristics and outcomes at discharge. Patients hospitalized for mucormycosis during March-July 2021 were included. Mucormycosis was diagnosed based on mycological confirmation on direct microscopy (KOH/Calcofluor white stain), culture, histopathology, or supportive evidence from endoscopy or imaging. After consent, trained data collectors used medical records and telephonic interviews to capture data in a pre-tested structured questionnaire. At baseline, we recruited 686 patients from 26 study hospitals, of whom 72.3% were males, 78% had a prior history of diabetes, 53.2% had a history of corticosteroid treatment, and 80% were associated with COVID-19. Pain, numbness or swelling of the face were the commonest symptoms (73.3%). Liposomal Amphotericin B was the commonest drug formulation used (67.1%), and endoscopic sinus surgery was the most common surgical procedure (73.6%). At discharge, the disease was stable in 43.3%, in regression for 29.9% but 9.6% died during hospitalization. Among survivors, commonly reported disabilities included facial disfigurement (18.4%) and difficulties in chewing/swallowing (17.8%). Though the risk of mortality was only 1 in 10, the disability due to the disease was very high. This cohort study could enhance our understanding of the disease's clinical progression and help frame standard treatment guidelines.

2.
Hum Vaccin Immunother ; 20(1): 2304974, 2024 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38512394

RESUMO

AZD1222 (ChAdOx1 nCoV-19) is a replication-deficient adenoviral vectored coronavirus disease-19 (COVID-19) vaccine that is manufactured as SII-ChAdOx1 nCoV-19 by the Serum Institute of India Pvt Ltd following technology transfer from Oxford University/AstraZeneca. The non-inferiority of SII-ChAdOx1 nCoV-19 with AZD1222 was previously demonstrated in an observer-blind, phase 2/3 immuno-bridging study (trial registration: CTRI/2020/08/027170). In this analysis of immunogenicity and safety data 6 months post first vaccination (Day 180), 1,601 participants were randomized 3:1 to SII-ChAdOx1 nCoV-19 or AZD1222 (immunogenicity/reactogenicity cohort n = 401) and 3:1 to SII-ChAdOx1 nCoV-19 or placebo (safety cohort n = 1,200). Immunogenicity was measured by anti-severe acute respiratory syndrome coronavirus 2 spike (anti-S) binding immunoglobulin G and neutralizing antibody (nAb) titers. A decline in anti-S titers was observed in both vaccine groups, albeit with a greater decline in SII-ChAdOx1 nCoV-19 vaccinees (geometric mean titer [GMT] ratio [95% confidence interval (CI) of SII-ChAdOx1 nCoV-19 to AZD1222]: 0.60 [0.41-0.87]). Consistent similar decreases in nAb titers were observed between vaccine groups (GMT ratio [95% CI]: 0.88 [0.44-1.73]). No cases of severe COVID-19 were reported following vaccination, while one case was observed in the placebo group. No causally related serious adverse events were reported through 180 days. No thromboembolic or autoimmune adverse events of special interest were reported. Collectively, these data illustrate that SII-ChAdOx1 nCoV-19 maintained a high level of immunogenicity 6 months post-vaccination. SII-ChAdOx1 nCoV-19 was safe and well tolerated.


Assuntos
COVID-19 , ChAdOx1 nCoV-19 , Adulto , Humanos , Vacinas contra COVID-19/efeitos adversos , Seguimentos , COVID-19/prevenção & controle , Imunoglobulina G , Imunogenicidade da Vacina , Anticorpos Antivirais
3.
Front Oncol ; 12: 798704, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35402248

RESUMO

Breast cancer is one of the most common diseases in the United States with 1 in 8 women developing the disease in her lifetime. Women who develop breast cancer are often post-menopausal and undergo a complex sequence of treatments including surgery, chemotherapy, and aromatase inhibitor therapy. Both independently and through potential interactions, these factors and treatments are associated with behavioral comorbidities reported in patients (e.g., fatigue), although the underlying neurobiological mechanisms are poorly understood. Currently, brain imaging is the most feasible way to assess neurobiology in patients. Indeed, breast cancer patients display alterations in white matter connections and chemotherapy is associated with decreased white and gray matter in the corpus callosum and cortex as well as decreased hippocampal volume. However, imaging in breast cancer rodent models is lacking, impeding translation of the mechanistic neurobiological findings made possible through modeling. Furthermore, current rodent models of breast cancer often lack the complexity of typical multimodal breast cancer treatments, thereby limiting translational value. The present study aimed to develop a comprehensive model of post-menopausal breast cancer survival using immunocompetent ovariectomized mice, including an orthotopic syngeneic tumor, surgical tumor removal, chemotherapy, and aromatase inhibitor therapy. Using this model, we systematically investigated the cumulative effects of chemotherapy and hormone replacement therapy on neurostructure and behavior using diffusion weighted imaging, open field test, and spontaneous alternation test. Our previous findings, in a simplified chemotherapy-only model, indicate that this regimen of chemotherapy causes circulating and central inflammation concurrent with reduced locomotor activity. The current study, in the more comprehensive model, has recapitulated the peripheral inflammation coincident with reduced locomotor activity as well as demonstrated that chemotherapy also drives widespread changes in brain anisotropy. Validating the clinical relevance of this comprehensive rodent breast cancer model will allow for additional neurobiological investigations of the interactions among various cancer components associated with behavioral comorbidities, as well as the relationship between these mechanisms and neurostructural imaging changes that can be measured in cancer patients.

4.
Artigo em Inglês | MEDLINE | ID: mdl-33239258

RESUMO

BACKGROUND: We used the highly prosocial prairie vole to test the hypothesis that higher-order brain structure-microarchitecture and functional connectivity (FC)-would differ between males from populations with distinctly different levels of prosocial behavior. Specifically, we studied males from Illinois (IL), which display high levels of prosocial behavior, and first generation males from Kansas dams and IL males (KI), which display the lowest level of prosocial behavior and higher aggression. Behavioral differences between these males are associated with overexpression of estrogen receptor alpha in the medial amygdala and bed nucleus of the stria terminalis and neuropeptide expression in the paraventricular nucleus. METHODS: We compared apparent diffusion coefficient, fractional anisotropy, and blood oxygen level-dependent resting-state FC between males. RESULTS: IL males displayed higher apparent diffusion coefficient in regions associated with prosocial behavior, including the bed nucleus of the stria terminalis, paraventricular nucleus, and anterior thalamic nuclei, while KI males showed higher apparent diffusion coefficient in the brainstem. KI males showed significantly higher fractional anisotropy than IL males in 26 brain regions, with the majority being in the brainstem reticular activating system. IL males showed more blood oxygen level-dependent resting-state FC between the bed nucleus of the stria terminalis, paraventricular nucleus, and medial amygdala along with other brain regions, including the hippocampus and areas associated with social and reward networks. CONCLUSIONS: Our results suggest that gray matter microarchitecture and FC may play a role the expression of prosocial behavior and that differences in other brain regions, especially the brainstem, could be involved. The differences between males suggests that this system represents a potentially valuable model system for studying emotional differences and vulnerability to stress and addiction.


Assuntos
Arvicolinae , Pradaria , Animais , Arvicolinae/metabolismo , Encéfalo/metabolismo , Córtex Cerebral , Imagem de Difusão por Ressonância Magnética , Humanos , Masculino
5.
Artigo em Inglês | MEDLINE | ID: mdl-33622657

RESUMO

BACKGROUND: Efficacy of inhaled cannabis for treating pain is controversial. Effective treatment for chemotherapy-induced neuropathy represents an unmet medical need. We hypothesized that cannabis reduces neuropathic pain by reducing functional coupling in the raphe nuclei. METHODS: We assessed the impact of inhalation of vaporized cannabis plant (containing 10.3% Δ9-tetrahydrocannabinol/0.05% cannabidiol) or placebo cannabis on brain resting-state blood oxygen level-dependent functional connectivity and pain behavior induced by paclitaxel in rats. Rats received paclitaxel to produce chemotherapy-induced peripheral neuropathy or its vehicle. Behavioral and imaging experiments were performed after neuropathy was established and stable. Images were registered to, and analyzed using, a 3D magnetic resonance imaging rat atlas providing site-specific data on more than 168 different brain areas. RESULTS: Prior to vaporization, paclitaxel produced cold allodynia. Inhaled vaporized cannabis increased cold withdrawal latencies relative to prevaporization or placebo cannabis, consistent with Δ9-tetrahydrocannabinol-induced antinociception. In paclitaxel-treated rats, the midbrain serotonergic system, comprising the dorsal and median raphe, showed hyperconnectivity to cortical, brainstem, and hippocampal areas, consistent with nociceptive processing. Inhalation of vaporized cannabis uncoupled paclitaxel-induced hyperconnectivity patterns. No such changes in connectivity or cold responsiveness were observed following placebo cannabis vaporization. CONCLUSIONS: Inhaled vaporized cannabis plant uncoupled brain resting-state connectivity in the raphe nuclei, normalizing paclitaxel-induced hyperconnectivity to levels observed in vehicle-treated rats. Inhaled vaporized cannabis produced antinociception in both paclitaxel- and vehicle-treated rats. Our study elucidates neural circuitry implicated in the therapeutic effects of Δ9-tetrahydrocannabinol and supports a role for functional imaging studies in animals in guiding indications for future clinical trials.


Assuntos
Antineoplásicos , Cannabis , Doenças do Sistema Nervoso Periférico , Animais , Nociceptividade , Núcleos da Rafe , Ratos
6.
J Neurosci Methods ; 343: 108823, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32580061

RESUMO

BACKGROUND: Novel imaging technology and procedures were developed to study brain function in preadolescent awake marmosets never exposed to anesthesia. METHODS: A radiofrequency transmit and receive, head only volume coil was designed and integrated into a holding system. An acclimation procedure was developed without the use of anesthesia or sedation that allowed for awake imaging. Preadolescent 8-month old male and female marmosets were imaged for resting state BOLD functional connectivity to assess the status of the default mode network. Levels of reactivity during acclimation sessions and behavioral stress following imaging were assessed. RESULTS: Data on functional coupling in the default mode network suggest the organization of connectivity to the prefrontal cortex is not fully developed at 8 months of age. The stress associated with the imaging procedure is comparable to that observed when marmosets are removed from their home cage and temporarily isolated from the family. COMPARISON TO OTHER METHODS: The design of the radiofrequency coil provides B1 homogeneity across the entire brain without signal drop off. The unique design of the head cradle obviates the need for any stabilizing surgery, ear bars or bite bar and could be adapted to any size marmoset. The acclimation requires no anesthesia or sedation at any time in the early life of the developing marmoset, a condition that better reflects the human experience. CONCLUSION: A method is provided for imaging functional activity in the brain of fully awake preadolescent marmosets without any history of anesthesia or sedation.


Assuntos
Callithrix , Vigília , Animais , Encéfalo/diagnóstico por imagem , Feminino , Imageamento por Ressonância Magnética , Masculino , Tecnologia
7.
Inhal Toxicol ; 32(5): 200-217, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32475185

RESUMO

Objective: The rapid increase of cannabis consumption reinforces the need to elucidate the health hazards of this practice. The presence of fine particulate matter in cannabis smoke and vapor poses a major concern, as it may contribute to cardiopulmonary disease. To facilitate the assessment of risks associated with cannabis inhalation, we developed and characterized a method for exposing mice to cannabis in a way that mimics the delivery of the drug to the airways of smokers. Materials and Methods: Cannabis (10.3% THC, 0.05% CBD) was vaporized to generate aerosols with a reproducible particle profile. Aerosols were acutely delivered to male, adult C57BL/6 mice via a nose-only exposure system. Serum THC levels were measured for increasing cannabis doses. Blood pressure and heart rate were recorded at baseline and following exposure. Behavioral response to cannabis inhalation in the open field was documented. Awake neurological activity upon cannabis exposure was monitored using BOLD fMRI.Results and Discussion: Cannabis aerosols contained particles with count median diameter of 243 ± 39 nm and geometric standard deviation of 1.56 ± 0.06. Blood serum THC levels increased linearly with aerosolized mass and peaked at 136 ± 5 ng/mL. Cannabis inhalation decreased heart rate and blood pressure but promoted anxiety-like behavior. Observed differences in BOLD activation volumes linked cannabis to increased awareness to sensory stimuli and reduced behavioral arousal.Conclusions: Quantified physiological, behavioral, and neurological responses served as validation for our mouse model of cannabis inhalation. Animal models of aerosol exposure will be instrumental for uncovering the health outcomes of chronic cannabis use.


Assuntos
Ansiedade/induzido quimicamente , Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Cannabis , Dronabinol/sangue , Fumar Maconha , Modelos Animais , Administração por Inalação , Administração Intranasal , Aerossóis , Animais , Encéfalo/diagnóstico por imagem , Humanos , Masculino , Camundongos Endogâmicos C57BL , Modelos Biológicos , Tamanho da Partícula , Sistema Respiratório/metabolismo , Volatilização
8.
Neurobiol Pain ; 6: 100034, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31223138

RESUMO

Human and animal studies suggest that both traumatic nerve injury and toxic challenge with chemotherapeutic agents involves the reorganization of neural circuits in the brain. However, there have been no prospective studies, human or animal, using magnetic resonance imaging (MRI) to identify changes in brain neural circuitry that accompany the development of chemotherapy-induced neuropathic pain (i.e. within days following cessation of chemotherapy treatment and without the confound cancer). To this end, different MRI protocols were used to ascertain whether a reorganization of brain neural circuits is observed in otherwise normal rats exposed to the taxane chemotherapeutic agent paclitaxel. We conducted an imaging study to evaluate the impact of a well-established paclitaxel dosing regimen, validated to induce allodynia in control rats within eight days of treatment, on brain neural circuitry. Rats received either paclitaxel (2 mg/kg/day i.p; cumulative dose of 8 mg/kg) or its vehicle four times on alternate days (i.e. day 0, 2, 4, 6). Following the cessation of treatments (i.e. on day 8), all rats were tested for responsiveness to cold followed by diffusion weighted magnetic resonance imaging and assessment of resting state functional connectivity. Imaging data were analyzed using a 3D MRI rat with 173 segmented and annotated brain areas. Paclitaxel-treated rats were more sensitive to a cold stimulus compared to controls. Diffusion weighted imaging identified brain areas involved in the emotional and motivational response to chronic pain that were impacted by paclitaxel treatment. Affected brain regions included the prefrontal cortex, amygdala, hippocampus, hypothalamus and the striatum/nucleus accumbens. This putative reorganization of gray matter microarchitecture formed a continuum of brain areas stretching from the basal medial/lateral forebrain to the midbrain. Resting state functional connectivity showed reorganization between the periaqueductal gray, a key node in nociceptive neural circuitry, and connections to the brainstem. Our results, employing different imaging modalities to assess the central nervous system effects of chemotherapy, fit the theory that chronic pain is regulated by emotion and motivation and influences activity in the periaqueductal gray and brainstem to modulate pain perception.

9.
Dis Model Mech ; 11(6)2018 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-29752287

RESUMO

RNASET2 deficiency in humans is associated with infant cystic leukoencephalopathy, which causes psychomotor impairment, spasticity and epilepsy. A zebrafish mutant model suggests that loss of RNASET2 function leads to neurodegeneration due to the accumulation of non-degraded RNA in the lysosomes. The goal of this study was to characterize the first rodent model of RNASET2 deficiency. The brains of 3- and 12-month-old RNaseT2 knockout rats were studied using multiple magnetic resonance imaging modalities and behavioral tests. While T1- and T2-weighted images of RNaseT2 knockout rats exhibited no evidence of cystic lesions, the prefrontal cortex and hippocampal complex were enlarged in knockout animals. Diffusion-weighted imaging showed altered anisotropy and putative gray matter changes in the hippocampal complex of the RNaseT2 knockout rats. Immunohistochemistry for glial fibrillary acidic protein (GFAP) showed the presence of hippocampal neuroinflammation. Decreased levels of lysosome-associated membrane protein 2 (LAMP2) and elevated acid phosphatase and ß-N-acetylglucosaminidase (NAG) activities indicated that the RNASET2 knockout rats likely had altered lysosomal function and potential defects in autophagy. Object recognition tests confirmed that RNaseT2 knockout rats exhibited memory deficits. However, the Barnes maze, and balance beam and rotarod tests indicated there were no differences in spatial memory or motor impairments, respectively. Overall, patients with RNASET2 deficiency exhibited a more severe neurodegeneration phenotype than was observed in the RNaseT2 knockout rats. However, the vulnerability of the knockout rat hippocampus as evidenced by neuroinflammation, altered lysosomal function and cognitive defects indicates that this is still a useful in vivo model to study RNASET2 function.


Assuntos
Endorribonucleases/genética , Hipocampo/patologia , Transtornos da Memória/genética , Transtornos da Memória/patologia , Doenças Neurodegenerativas/genética , Ribonucleases/genética , Animais , Anisotropia , Mapeamento Encefálico , Sistemas CRISPR-Cas/genética , Cognição , Técnicas de Inativação de Genes , Proteína Glial Fibrilar Ácida/metabolismo , Hipocampo/fisiopatologia , Humanos , Inflamação/patologia , Lisossomos/metabolismo , Imageamento por Ressonância Magnética , Transtornos da Memória/fisiopatologia , Atividade Motora , Doenças Neurodegenerativas/patologia , Doenças Neurodegenerativas/fisiopatologia , Tamanho do Órgão , Ratos Sprague-Dawley
10.
J Parkinsons Dis ; 8(2): 281-301, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29710734

RESUMO

BACKGROUND: Genetic models of Parkinson's disease (PD) coupled with advanced imaging techniques can elucidate neurobiological disease progression, and can help identify early biomarkers before clinical signs emerge. PTEN-induced putative kinase 1 (PINK1) helps protect neurons from mitochondrial dysfunction, and a mutation in the associated gene is a risk factor for recessive familial PD. The PINK1 knockout (KO) rat is a novel model for familial PD that has not been neuroradiologically characterized for alterations in brain structure/function, alongside behavior, prior to 4 months of age. OBJECTIVE: To identify biomarkers of presymptomatic PD in the PINK1 -/- rat at 3 months using magnetic resonance imaging techniques. METHODS: At postnatal weeks 12-13; one month earlier than previously reported signs of motor and cognitive dysfunction, this study combined imaging modalities, including assessment of quantitative anisotropy across 171 individual brain areas using an annotated MRI rat brain atlas to identify sites of gray matter alteration between wild-type and PINK1 -/- rats. RESULTS: The olfactory system, hypothalamus, thalamus, nucleus accumbens, and cerebellum showed differences in anisotropy between experimental groups. Molecular analyses revealed reduced levels of glutathione, ATP, and elevated oxidative stress in the substantia nigra, striatum and deep cerebellar nuclei. Mitochondrial genes encoding proteins in Complex IV, along with mRNA levels associated with mitochondrial function and genes involved in glutathione synthesis were reduced. Differences in brain structure did not align with any cognitive or motor impairment. CONCLUSIONS: These data reveal early markers, and highlight novel brain regions involved in the pathology of PD in the PINK1 -/- rat before behavioral dysfunction occurs.


Assuntos
Encéfalo/metabolismo , Doença de Parkinson/metabolismo , Proteínas Quinases/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Encéfalo/diagnóstico por imagem , Metilação de DNA , Modelos Animais de Doenças , Glutationa/metabolismo , Aprendizagem/fisiologia , Imageamento por Ressonância Magnética , Masculino , Aprendizagem em Labirinto/fisiologia , Atividade Motora/fisiologia , Estresse Oxidativo/fisiologia , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/genética , Proteínas Quinases/genética , Ratos , Ratos Long-Evans , Ratos Transgênicos , Reconhecimento Psicológico/fisiologia
11.
Biomaterials ; 170: 26-36, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29649747

RESUMO

Interest in theranostic agents has continued to grow because of their promise for simultaneous cancer detection and therapy. A platform-based nanosized combination agent suitable for the enhanced diagnosis and treatment of cancer was prepared using polymeric polyethylene glycol-phosphatidylethanolamine-based micelles loaded with both, poorly soluble chemotherapeutic agent paclitaxel and hydrophobic superparamagnetic iron oxide nanoparticles (SPION), a Magnetic Resonance Imaging contrast agent. The co-loaded paclitaxel and SPION did not affect each other's functional properties in vitro. In vivo, the resulting paclitaxel-SPION-co-loaded PEG-PE micelles retained their Magnetic Resonance contrast properties and apoptotic activity in breast and melanoma tumor mouse models. Such theranostic systems are likely to play a significant role in the combined diagnosis and therapy that leads to a more personalized and effective form of treatment.


Assuntos
Meios de Contraste/química , Sistemas de Liberação de Medicamentos , Nanopartículas de Magnetita/química , Micelas , Paclitaxel/administração & dosagem , Polímeros/química , Nanomedicina Teranóstica/métodos , Água/química , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Feminino , Imageamento por Ressonância Magnética , Nanopartículas de Magnetita/ultraestrutura , Masculino , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Solubilidade
12.
PLoS One ; 12(4): e0174774, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28445527

RESUMO

Dopaminergic reward dysfunction in addictive behaviors is well supported in the literature. There is evidence that alterations in synchronous neural activity between brain regions subserving reward and various cognitive functions may significantly contribute to substance-related disorders. This study presents the first evidence showing that a pro-dopaminergic nutraceutical (KB220Z) significantly enhances, above placebo, functional connectivity between reward and cognitive brain areas in the rat. These include the nucleus accumbens, anterior cingulate gyrus, anterior thalamic nuclei, hippocampus, prelimbic and infralimbic loci. Significant functional connectivity, increased brain connectivity volume recruitment (potentially neuroplasticity), and dopaminergic functionality were found across the brain reward circuitry. Increases in functional connectivity were specific to these regions and were not broadly distributed across the brain. While these initial findings have been observed in drug naïve rodents, this robust, yet selective response implies clinical relevance for addicted individuals at risk for relapse, who show reductions in functional connectivity after protracted withdrawal. Future studies will evaluate KB220Z in animal models of addiction.


Assuntos
Encéfalo/efeitos dos fármacos , Catecolaminas/farmacologia , Dopaminérgicos/farmacologia , Monoaminoxidase/farmacologia , Neprilisina/farmacologia , Animais , Encéfalo/anatomia & histologia , Encéfalo/fisiologia , Mapeamento Encefálico , Cognição/efeitos dos fármacos , Hipocampo/anatomia & histologia , Hipocampo/efeitos dos fármacos , Hipocampo/fisiologia , Imageamento por Ressonância Magnética , Masculino , Núcleo Accumbens/anatomia & histologia , Núcleo Accumbens/efeitos dos fármacos , Núcleo Accumbens/fisiologia , Efeito Placebo , Ratos , Ratos Long-Evans , Núcleos Talâmicos/anatomia & histologia , Núcleos Talâmicos/efeitos dos fármacos , Núcleos Talâmicos/fisiologia
13.
Horm Behav ; 82: 56-63, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27154458

RESUMO

The ovarian hormone estrogen has been implicated in schizophrenia symptomatology. Low levels of estrogen are associated with an increase in symptom severity, while exogenous estrogen increases the efficacy of antipsychotic medication, pointing at a possible interaction between estrogen and the dopaminergic system. The aim of this study is to further investigate this interaction in an animal model of some aspects of schizophrenia using awake functional magnetic resonance imaging. Animals receiving 17ß-estradiol and haloperidol were scanned and BOLD activity was assessed in response to amphetamine. High 17ß-estradiol replacement and chronic haloperidol treatment showed increased BOLD activity in regions of interest and neural networks associated with schizophrenia (hippocampal formations, habenula, amygdala, hypothalamus etc.), compared with low, or no 17ß-estradiol. These data show that chronic haloperidol treatment has a sensitizing effect, possibly on the dopaminergic system, and this effect is dependent on hormonal status, with high 17ß-estradiol showing the greatest BOLD increase. Furthermore, these experiments further support the use of imaging techniques in studying schizophrenia, as modeled in the rat, but can be extended to addiction and other disorders.


Assuntos
Anfetamina/farmacologia , Dopamina/metabolismo , Estradiol/farmacologia , Haloperidol/farmacologia , Oxigênio/sangue , Oxigênio/fisiologia , Vigília/efeitos dos fármacos , Animais , Antipsicóticos/farmacologia , Modelos Animais de Doenças , Feminino , Imageamento por Ressonância Magnética , Ovariectomia , Ratos , Ratos Sprague-Dawley
14.
Drug Deliv ; 23(3): 968-80, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-24901206

RESUMO

OBJECTIVE: Ovarian cancer is a highly lethal disease in which the majority of patients eventually demonstrate multidrug resistance. Develop a novel active targeted theranostic nanomedicine designed to overcome drug efflux mechanisms, using a Generally Regarded As Safe (GRAS) grade nanoemulsion (NE) as a clinically relevant platform. MATERIALS AND METHODS: The NEs surface-functionalized with folate and gadolinium, were made using GRAS grade excipients and a high-shear microfluidization process. Efficacy was evaluated in ovarian cancer cells, SKOV3 and SKOV3TR. The NE accumulation in tumors was evaluated in SKOV3 tumor-bearing mice by magnetic resonance imaging (MRI). RESULTS AND DISCUSSION: The NE with particle size < 150 nm were stable in plasma and parenteral fluids for 24 h. Ovarian cancer cells in vitro efficiently took up the non-targeted and folate-targeted NEs; improved cytotoxicity was observed for the folate-targeted NEs showing a 270-fold drop in the IC50 in SKOV3TR cells as compared to docetaxel alone. The addition of gadolinium did not affect cell viability in vitro, but showed relaxation times comparable to Magnevist®. Folate-targeted NEs accumulated in tumors for prolonged period of time compared to Magnevist® and showed enhanced contrast compared to non-targeted NEs with MRI in SKOV3 tumor-bearing mice suggesting active targeting of NEs due to folate modification. CONCLUSIONS: A folate-targeted, theranostic NE delivers docetaxel by receptor mediated endocytosis that shows enhanced cytotoxicity capable of overcoming ABC transporter mediated taxane resistance. The diagnostic capability of the targeted nanomedicine showed enhanced contrast in tumors compared to clinically relevant MRI contrast agent Magnevist®.


Assuntos
Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Emulsões/química , Nanopartículas/química , Neoplasias Ovarianas/tratamento farmacológico , Taxoides/administração & dosagem , Taxoides/química , Nanomedicina Teranóstica , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Hidrocarbonetos Aromáticos com Pontes/administração & dosagem , Hidrocarbonetos Aromáticos com Pontes/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Química Farmacêutica/métodos , Docetaxel , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Feminino , Ácido Fólico/administração & dosagem , Ácido Fólico/química , Gadolínio/administração & dosagem , Gadolínio/química , Humanos , Camundongos , Camundongos Nus , Tamanho da Partícula
15.
Psychoneuroendocrinology ; 56: 200-12, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25827963

RESUMO

Previous studies demonstrate that schizophrenia symptomatology in women is dependent upon estrogen levels. Estrogen has beneficial properties when administered in conjunction with antipsychotics, and estrogen also alters, in rats, dopamine neurotransmission, which is a common target of all antipsychotic medications, suggesting a possible interaction between the two. The aim of the current study was to investigate this possible interaction using functional magnetic resonance imaging in awake, female rats. Amphetamine-sensitized, ovariectomized rats receiving no, chronic low, or phasic high levels of estradiol replacement were used, and changes in blood-oxygen-level-dependent (BOLD) signal were recorded over time in response to an acute amphetamine injection. Increasing levels of estradiol enhanced BOLD activation in pathways previously known to be implicated in schizophrenia symptomatology, such as the mesocorticolimbic, habenular and olfactory pathways, as well as more widespread areas. We propose here the first comprehensive "amphetamine activation map" integrating brain regions where amphetamine-related BOLD activity is influenced by estrogen levels in sensitized female rats.


Assuntos
Anfetamina/farmacologia , Estimulantes do Sistema Nervoso Central/farmacologia , Estrogênios/metabolismo , Rede Nervosa/efeitos dos fármacos , Animais , Mapeamento Encefálico , Relação Dose-Resposta a Droga , Estradiol/farmacologia , Terapia de Reposição de Estrogênios , Feminino , Imageamento por Ressonância Magnética , Ovariectomia , Oxigênio/sangue , Ratos , Ratos Sprague-Dawley
16.
Pharm Res ; 32(8): 2753-63, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25732960

RESUMO

PURPOSE: Platinum-based therapies are the first line treatments for most types of cancer including ovarian cancer. However, their use is associated with dose-limiting toxicities and resistance. We report initial translational studies of a theranostic nanoemulsion loaded with a cisplatin derivative, myrisplatin and pro-apoptotic agent, C6-ceramide. METHODS: The surface of the nanoemulsion is annotated with an endothelial growth factor receptor (EGFR) binding peptide to improve targeting ability and gadolinium to provide diagnostic capability for image-guided therapy of EGFR overexpressing ovarian cancers. A high shear microfludization process was employed to produce the formulation with particle size below 150 nm. RESULTS: Pharmacokinetic study showed a prolonged blood platinum and gadolinium levels with nanoemulsions in nu/nu mice. The theranostic nanoemulsions also exhibited less toxicity and enhanced the survival time of mice as compared to an equivalent cisplatin treatment. CONCLUSIONS: Magnetic resonance imaging (MRI) studies indicate the theranostic nanoemulsions were effective contrast agents and could be used to track accumulation in a tumor. The MRI study additionally indicate that significantly more EGFR-targeted theranostic nanoemulsion accumulated in a tumor than non-targeted nanoemulsuion providing the feasibility of using a targeted theranostic agent in conjunction with MRI to image disease loci and quantify the disease progression.


Assuntos
Antineoplásicos/administração & dosagem , Antineoplásicos/uso terapêutico , Ceramidas/administração & dosagem , Ceramidas/uso terapêutico , Receptores ErbB/efeitos dos fármacos , Compostos Organoplatínicos/administração & dosagem , Compostos Organoplatínicos/uso terapêutico , Neoplasias Ovarianas/tratamento farmacológico , Nanomedicina Teranóstica/métodos , Animais , Antineoplásicos/farmacocinética , Plaquetas/metabolismo , Ceramidas/farmacocinética , Sistemas de Liberação de Medicamentos , Feminino , Gadolínio/metabolismo , Camundongos , Microfluídica , Compostos Organoplatínicos/farmacocinética , Tamanho da Partícula , Análise de Sobrevida , Distribuição Tecidual
17.
Int J Radiat Biol ; 90(9): 799-806, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24991879

RESUMO

PURPOSE: To assess the long-term effects of fractionated whole brain irradiation (fWBI) using diffusion tensor imaging (DTI) and behavior in a pediatric rodent model for the clinical presentation of adult pediatric cancer survivors. MATERIALS AND METHODS: Five-week-old, male F344xBN rats were randomized to receive 0, 5, or 6.5 Gy fractions biweekly for 3 weeks, resulting in Sham, Irradiated-30 (IR-30) and IR-39 Gy total dose groups. Magnetic Resonance Imaging occurred at 1, 3, 6 and 9 months with behavioral assessment at 10-11 months post-fWBI. RESULTS: Irradiation reduced brain size (p < 0.001) and body weight (p < 0.001) proportionate to dose. At 1 month post-fWBI and throughout follow-up, diffusion was reduced in IR-30 and IR-39 relative to shams (p < 0.001). IR-30 but not IR-39 rats were impaired relative to Shams on the reversal trial of the Morris Water Maze (p < 0.05), and IR-30 rats preferred a striatum- mediated strategy (p < 0.06). CONCLUSIONS: Hippocampal performance was impaired in IR-30 but not IR-39 animals. While gross size differences exist, white matter integrity is preserved in rats after fWBI at 5 weeks. This significant departure from childhood cancer survivors and single fraction rodent studies where white matter degradation is a prominent feature are discussed.


Assuntos
Encéfalo/efeitos da radiação , Cognição/efeitos da radiação , Imagem de Tensor de Difusão , Fracionamento da Dose de Radiação , Radioterapia/métodos , Animais , Comportamento Animal/efeitos da radiação , Neoplasias Encefálicas/radioterapia , Hipocampo/efeitos da radiação , Imageamento por Ressonância Magnética , Masculino , Aprendizagem em Labirinto , Modelos Animais , Distribuição Aleatória , Ratos , Ratos Endogâmicos F344
18.
Pharm Res ; 31(10): 2724-34, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24792826

RESUMO

PURPOSE: The main objective of this study was to develop and evaluate therapeutic efficacy and safety following systemic delivery of a peptide analgesic into the CNS using an oil-in-water nanoemulsion system. METHODS: We have formulated a safe and effective, omega-3 rich polyunsaturated fatty acid containing oil-in-water nanoemulsion formulation, for encapsulating and delivering chemically-modified DALDA, a potent mu-opioid peptide analogue, to the CNS. One of the challenges with CNS delivery is the lack of a non-invasive bioanalytical technique to confirm CNS uptake and therapeutic efficacy. Using blood oxygen-level dependent (BOLD) functional magenetic resonance imaging (fMRI), we provide quantitative evidence of nanoemulsion-based delivery and analgesic activity of DALDA analogue in capsaicin-induced awake rat model of pain. RESULTS: Nanoemulsion formulation effectively encapsulated the modified analgesic peptide and demonstrated efficacy in the capsaicin- pain induced functional magnetic resonance imaging model in rodents. Preliminary safety evaluations show that the nanoemulsion system was well tolerated and did not cause any acute negative effects. CONCLUSIONS: Overall, these results show tremendous opportunity for the development of modified peptide analgesic-encapsulated nanoemulsion formulations for CNS delivery and therapeutic efficacy.


Assuntos
Analgésicos/administração & dosagem , Encéfalo/efeitos dos fármacos , Portadores de Fármacos/química , Nanoestruturas/química , Oligopeptídeos/administração & dosagem , Receptores Opioides mu/agonistas , Analgésicos/química , Analgésicos/farmacocinética , Analgésicos/uso terapêutico , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Capsaicina/farmacologia , Modelos Animais de Doenças , Emulsões , Imageamento por Ressonância Magnética , Masculino , Camundongos Endogâmicos , Oligopeptídeos/química , Oligopeptídeos/farmacocinética , Oligopeptídeos/uso terapêutico , Dor/tratamento farmacológico , Dor/metabolismo , Dor/patologia , Ratos Sprague-Dawley
19.
PLoS One ; 8(7): e68426, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23869218

RESUMO

OBJECTIVE: Cytokines (IL-6, IL-8 and TNF-α), sCD163, and C-reactive protein were serially measured in an attempt to identify a set of tests which can reliably confirm or refute the diagnosis of neonatal sepsis at an early stage. METHODS: One hundred neonates suspected to have sepsis on clinical grounds and who met the inclusion criteria were enrolled for the study. Based on the positive or negative blood culture reports they were classified as infected (n=50) and non-infected (n=50) neonates respectively. Fifty healthy neonates without any signs of sepsis were also included in the study as control group. The initial blood sample was taken on day 0 (at the time of sepsis evaluation) and two further samples were taken on days 1 and 2 for monitoring the clinical progress and response to treatment. In the control group the cord blood and 48 hours venous sample was collected. Plasma CRP (ng/ml), IL-6 (pg/ml), IL-8 (pg/ml), TNF-α (ng/ml) and sCD163 (ng/ml) were determined by double antibody method Enzyme Linked Immunosorbent Assay in all the three blood samples. RESULTS: The cut of levels for CRP at >19,689 ng/ml had a sensitivity of 68%, specificity of 92%, for IL-6 at >95.32 pg/ml had a sensitivity of 54%, specificity of 96%, for IL-8 at >70.86 pg/ml had a sensitivity of 78%, specificity of 70%, for sCD163 at >896.78 ng/ml had a sensitivity of 100%, specificity of 88% for the diagnosis of infection before antibiotics. TNF-α levels of >12.6 ng/ml showed 100% sensitivity and 72% specificity for the diagnosis of inflammation. CONCLUSION: The most powerful predictor to differentiate between the non-infected and infected neonates before antibiotics was sCD163. The most powerful indicator for evaluation of prognosis is IL-6. sCD163 can be used alone to screen for sepsis in neonates before the results of blood culture are received.


Assuntos
Antígenos CD/sangue , Antígenos de Diferenciação Mielomonocítica/sangue , Proteína C-Reativa/metabolismo , Interleucina-6/sangue , Interleucina-8/sangue , Receptores de Superfície Celular/sangue , Sepse/diagnóstico , Fator de Necrose Tumoral alfa/sangue , Biomarcadores/sangue , Estudos de Casos e Controles , Diagnóstico Precoce , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Recém-Nascido , Masculino , Sensibilidade e Especificidade , Sepse/sangue
20.
Nanomedicine (Lond) ; 5(8): 1173-82, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21039195

RESUMO

AIMS: The development of noninvasive imaging techniques for the assessment of cancer treatment is rapidly becoming highly important. The aim of the present study is to show that magnetic cationic liposomes (MCLs), incorporating superparamagnetic iron oxide nanoparticles (SPIONs), are a versatile theranostic nanoplatform for enhanced drug delivery and monitoring of cancer treatment. MATERIALS & METHODS: MCLs (with incorporated high SPION cargo) were administered to a severe combined immunodeficiency mouse with metastatic (B16-F10) melanoma grown in the right flank. Pre- and post-injection magnetic resonance (MR) images were used to assess response to magnetic targeting effects. Biodistribution studies were conducted by ¹¹¹In-labeled MCLs and the amount of radioactivity recovered was used to confirm the effect of targeting for intratumoral administrations. RESULTS: We have shown that tumor signal intensities in T2-weighted MR images decreased by an average of 20 ± 5% and T2* relaxation times decreased by 14 ± 7 ms 24 h after intravenous administration of our MCL formulation. This compares to an average decrease in tumor signal intensity of 57 ± 12% and a T2* relaxation time decrease of 27 ± 8 ms after the same time period with the aid of magnetic guidance. CONCLUSION: MR and biodistribution analysis clearly show the efficacy of MCLs as MRI contrast agents, prove the use of magnetic guidance, and demonstrate the potential of MCLs as agents for imaging, guidance and therapeutic delivery.


Assuntos
Imageamento por Ressonância Magnética/métodos , Neoplasias/irrigação sanguínea , Neoplasias/patologia , Animais , Meios de Contraste , Portadores de Fármacos , Ácidos Graxos Monoinsaturados/administração & dosagem , Compostos Férricos , Corantes Fluorescentes/administração & dosagem , Humanos , Injeções Intravenosas , Cinética , Lipossomos/administração & dosagem , Lipossomos/uso terapêutico , Magnetismo , Melanoma/irrigação sanguínea , Melanoma/tratamento farmacológico , Melanoma/patologia , Camundongos , Camundongos SCID , Nanopartículas , Metástase Neoplásica , Compostos de Amônio Quaternário/administração & dosagem , Distribuição Tecidual
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