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1.
Heliyon ; 10(1): e23482, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38187303

RESUMO

Introduction: One of the causes of congenital hearing loss are infections suffered by the mother during pregnancy. The objective of this study was to investigate the effects on hearing in newborns to SARS-CoV-2 seropositive mothers during pregnancy. We also studied the hearing impact in the first year of life of the newborns to investigate whether neonatal infection produced a risk of infantile sensorineural hearing loss. Material and methods: All children born in our center whose mother had been infected with SARS-CoV-2 positive COVID were included and were audiologically studied at two and a half months and at one year of life. All infants were evaluated by brainstem evoked response audiometry (BERA) and auditory steady-state responses (ASSR). Results: The range of the latencies for BERA founded were inside the desired ranges of normality both at two and a half months and at one year of life No significant differences by sex and ears were found in the BERA performed (p > 0,05). The mean ASSR values were found to be significantly below 30 dB in all frequencies studied both at two and a half months, and at one year of life (p < 0,05). Conclusion: There is no association between COVID-19 infection during pregnancy and neonatal hearing loss. Further studies are needed to clarify this field since it is still unclear whether pregnant women infected with SARS-CoV-2 can produce hearing alterations in their newborns according to the current evidence in the literature.

2.
Antioxidants (Basel) ; 12(11)2023 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-38001847

RESUMO

Age-related hearing loss (ARHL) impairs the quality of life in elderly persons. ARHL is associated with comorbidities, such as depression, falls, or frailty. Frailty syndrome is related to poor health outcomes in old age. ARHL is a potentially modifiable risk factor for frailty. Oxidative stress has been proposed as a key factor underlying the onset and/or development of ARHL and frailty. Cocoa has high levels of polyphenols and provides many health benefits due to its antioxidant properties. Male and female C57Bl/6J mice were randomly assigned to two study groups: animals receiving a cocoa-supplemented diet and the other receiving a standard diet. Then, at the ages of 6, 14, and 22 months, hearing and frailty were measured in all mice. Auditory steady-state responses (ASSR) threshold shifts were measured to different frequencies. The frailty score was based on the "Valencia Score" adapted to the experimental animals. The total antioxidant capacity and total polyphenols in urine samples were also measured. Significant improvements in hearing ability are observed in the cocoa groups at 6, 14, and 22 months compared to the no cocoa group. The cocoa diet significantly retards the development of frailty in mice. Cocoa increases the concentration of polyphenols excreted in the urine, which increases the total antioxidant capacity. In conclusion, cocoa, due to its antioxidant properties, leads to significant protection against ARHL and frailty.

3.
Nutrients ; 15(3)2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36771251

RESUMO

Cocoa, rich in polyphenols, has been reported to provide many health benefits due to its antioxidant properties. In this study, we investigated the effect of Cocoa polyphenols extract (CPE) against oxidative stress-induced cellular senescence using a hydrogen peroxide (H2O2)-induced cellular senescence model in three auditory cells lines derived from the auditory organ of a transgenic mouse: House Ear Institute-Organ of Corti 1 (HEI-OC1), Organ of Corti-3 (OC-k3), and Stria Vascularis (SV-k1) cells. Our results showed that CPE attenuated senescent phenotypes, including senescence-associated ß-galactosidase expression, cell proliferation, alterations of morphology, oxidative DNA damage, mitochondrial dysfunction by inhibiting mitochondrial reactive oxygen species (mtROS) generation, and related molecules expressions such as forkhead box O3 (FOXO3) and p53. In addition, we determined that CPE induces expression of sirtuin 1 (SIRT1) and sirtuin 3 (SIRT3), and it has a protective role against cellular senescence by upregulation of SIRT1 and SIRT3. These data indicate that CPE protects against senescence through SIRT1, SIRT3, FOXO3, and p53 in auditory cells. In conclusion, these results suggest that Cocoa has therapeutic potential against age-related hearing loss (ARHL).


Assuntos
Sirtuína 1 , Sirtuína 3 , Camundongos , Animais , Sirtuína 1/metabolismo , Sirtuína 3/genética , Sirtuína 3/metabolismo , Polifenóis/farmacologia , Peróxido de Hidrogênio/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Senescência Celular , Estresse Oxidativo , Camundongos Transgênicos
4.
J Voice ; 37(5): 799.e13-799.e15, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34088573

RESUMO

The spinal accessory nerve innervates the sternocleidomastoid and trapezius muscles, but the internal branch from the spinal accessory nerve is also contributing to the motor innervation of the larynx. For the first time, we report a case of an impairment of sternocleidomastoid, trapezius, and thyroarytenoid muscles from the same side. In our case, the anatomical variant that can explain this situation implies the cranial roots and some fibers from the spinal roots of the spinal accessory nerve to form the internal branch. In the case of agenesis of these spinal roots, the muscles reliant on it would be missing. For this reason, it is advisable to rule out laryngeal problems in patients with sternocleidomastoid and/or trapezius muscles impairment.


Assuntos
Nervo Acessório , Prega Vocal , Humanos , Nervo Acessório/fisiologia , Músculos do Pescoço , Músculos Laríngeos/inervação
5.
Antioxidants (Basel) ; 11(8)2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35892652

RESUMO

Presbycusis or Age-related hearing loss (ARHL) is a sensorineural hearing loss that affects communication, leading to depression and social isolation. Currently, there are no effective treatments against ARHL. It is known that cocoa products have high levels of polyphenol content (mainly flavonoids), that are potent anti-inflammatory and antioxidant agents with proven benefits for health. The objective is to determine the protective effect of cocoa at the cellular and molecular levels in Presbycusis. For in vitro study, we used House Ear Institute-Organ of Corti 1 (HEI-OC1), stria vascularis (SV-k1), and organ of Corti (OC-k3) cells (derived from the auditory organ of a transgenic mouse). Each cell line was divided into a control group (CTR) and an H2O2 group (induction of senescence by an oxygen radical). Additionally, every group of every cell line was treated with the cocoa polyphenolic extract (CPE), measuring different markers of apoptosis, viability, the activity of antioxidant enzymes, and oxidative/nitrosative stress. The data show an increase of reactive oxidative and nitrogen species (ROS and RNS, respectively) in senescent cells compared to control ones. CPE treatment effectively reduced these high levels and correlated with a significant reduction in apoptosis cells by inhibiting the mitochondrial-apoptotic pathway. Furthermore, in senescence cells, the activity of antioxidant enzymes (Superoxide dismutase, SOD; Catalase, CAT; and Glutathione peroxidase, GPx) was recovered after CPE treatment. Administration of CPE also decreased oxidative DNA damage in the auditory senescent cells. In conclusion, CPE inhibits the activation of senescence-related apoptotic signaling by decreasing oxidative stress in auditory senescent cells.

6.
Antioxidants (Basel) ; 10(9)2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34573129

RESUMO

Age-related hearing loss (ARHL) is an increasing and gradual sensorineural hearing dysfunction. Oxidative stress is an essential factor in developing ARHL; additionally, premature senescence of auditory cells induced by oxidative stress can produce hearing loss. Hydrogen peroxide (H2O2) represents a method commonly used to generate cellular senescence in vitro. The objective of the present paper is to study H2O2-induced senescence patterns in three auditory cell lines (House Ear Institute-Organ of Corti 1, HEI-OC1; organ of Corti, OC-k3, and stria vascularis, SV-k1 cells) to elucidate the intrinsic mechanisms responsible for ARHL. The auditory cells were exposed to H2O2 at different concentrations and times. The results obtained show different responses of the hearing cells concerning cell growth, ß-galactosidase activity, morphological changes, mitochondrial activation, levels of oxidative stress, and other markers of cell damage (Forkhead box O3a, FoxO3a, and 8-oxoguanine, 8-oxoG). Comparison between the responses of these auditory cells to H2O2 is a helpful method to evaluate the molecular mechanisms responsible for these auditory cells' senescence. Furthermore, this in vitro model could help develop anti-senescent therapeutic strategies for the treatment of AHRL.

7.
Pharmaceutics ; 13(8)2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34452203

RESUMO

Currently, new treatments are required to supplement the current standard of care for head and neck squamous cell carcinoma (HNSCC). The phosphatidylinositol3-kinase (PI3K) signaling pathway is commonly altered and activated in HNSCC. PHT-427 is a dual PI3K-mammalian target of the AKT/PDK1 inhibitor; however, to the best of our knowledge, the effect of the PHT-427 inhibitor on HNSCC has not been investigated. This study aims to evaluate the antitumoral effect of PHT-427-loaded polymeric nanoparticles based on α-tocopheryl succinate (α-TOS). The in vitro activity of PHT-427 was tested in hypopharynx carcinoma squamous cells (FaDu) to measure the cell viability, PI3KCA/AKT/PDK1 gene expression, and PI3KCA/AKT/PDK1 levels. Apoptosis, epidermal growth factor receptor (EGFR), and reactive oxygen species (ROS) were also measured. The presence of PHT-427 significantly enhances its antiproliferative and proapoptotic activity by inactivating the PI3K/AKT/PDK1 pathway. Nanoparticles (NPs) effectively suppress AKT/PDK1 expression. Additionally, NPs loaded with PHT-427 produce high oxidative stress levels that induce apoptosis. In conclusion, these results are promising in the use of this nanoformulation as a PHT-427 delivery system for effective HNSCC treatment.

8.
Artigo em Inglês | MEDLINE | ID: mdl-34063346

RESUMO

Aquaculture is an increasingly relevant sector in the exploitation of natural resources; therefore, it is appropriate to propose various models that include the fundamental variables for its economic-financial valuation from a business point of view. The objective of this paper is to analyze different models for the valuation of investment projects in a company in the aquaculture sector in order to conclude whether there is a model that represents a better valuation. Therefore, in this study, four valuation models have been applied, three classical models (net present value, internal rate of return, and payback) and a more recent model, real options (RO) for a company producing and marketing seaweed in Galicia (region located in the northwest of Spain). The results obtained, RO (€5,527,144.04) and net present value (€5,479,659.19), conclude that the RO model estimates a higher added value by taking into account in its calculations the flexibility given by the expansion option. Future lines of research include the application of valuation models that have been applied to companies belonging to the same sector in order to compare whether the results found are similar.


Assuntos
Alga Marinha , Comércio , Humanos , Investimentos em Saúde , Marketing , Espanha
9.
Drug Deliv ; 28(1): 1376-1388, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34180747

RESUMO

The prognosis of patients with recurrent or metastatic head and neck squamous cell cancer (HNSCC) is generally poor. New treatments are required to supplement the current standard of care. Paclitaxel (PTX), an effective chemotherapeutic for HNSCC, has serious side effects. A polymeric nanocarrier system was developed for the delivery of PTX to improve HNSCC treatment. This study aimed to evaluate the antitumor efficacy of PTX-loaded polymeric nanoparticles based on α-TOS (PTX-NPs) administered by direct intratumoral injection into a Hypopharynx carcinoma squamous cells (FaDu) tumor xenograft mouse model. The nanocarrier system based on block copolymers of polyethylene glycol (PEG) and a methacrylic derivative of α-TOS was synthesized and PTX was loaded into the delivery system. Tumor volume was measured to evaluate the antitumor effect of the PTX-NPs. The relative mechanisms of apoptosis, cell proliferation, growth, angiogenesis, and oxidative and nitrosative stress were detected by Western blotting, fluorescent probes, and immunohistochemical analysis. The antitumor activity results showed that compared to free PTX, PTX-NPs exhibited much higher antitumor efficacy and apoptosis-inducing in a FaDu mouse xenograft model and demonstrated an improved safety profile. Ki-67, EGFR, and angiogenesis markers (Factor VIII, CD31, and CD34) expression were significantly lower in the PTX-NPs group compared with other groups (p < .05). Also, PTX-NPs induced oxidative and nitrosative stress in tumor tissue. Direct administration of PTX-loaded polymeric nanoparticles based on α-Tocopheryl Succinate at the tumor sites, proved to be promising for HNSCC therapy.


Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/farmacologia , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Nanopartículas/química , Paclitaxel/administração & dosagem , Paclitaxel/farmacologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Química Farmacêutica , Portadores de Fármacos , Feminino , Camundongos , Camundongos Nus , Neovascularização Patológica/metabolismo , Polietilenoglicóis/química , Polímeros/química , Carga Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Eur Arch Otorhinolaryngol ; 278(12): 4831-4837, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33774737

RESUMO

PURPOSE: The study aimed to determine the incidence and long-term evolution of COVID-related olfactory (OD) and gustatory (GD) dysfunction, the recovery timeline, and the association with other symptoms. The secondary objective was to identify the predictive clinical factors for the evolution of these symptoms. METHODS: A prospective case-control study was conducted from March 15 to October 15, 2020, in health workers with COVID-19 related symptoms in a tertiary care hospital. 320 patients were included after 6 months of follow-up: 195 in the case group and 125 in the control group. Olfactory dysfunction (OD), dysosmia, and gustatory dysfunction (GD) onset and recovery rate after 6 months follow-up are analyzed in both groups. RESULTS: There were 125 (64.1%) in case group patients with OD and 118 (60.5%) with GD. Total or partial recovery OD and GD was found in 89%, mainly in the first 2 months. In the control group, there were 14 (11.2%) patients with OD and 33 (26.4%) patients with GD, with 100% of total/partial recovery. CONCLUSION: In both groups, OD and GD showed high-resolution rates during the first two months after the onset of symptoms. Nevertheless, 11% of the case group patients did not show any recovery, and the partial resolution was present in 30% of our patients, at the 6 months follow-up. We found a high correlation between OD and GD, both in the appearance of symptoms and in their recovery. Nasal obstruction and dyspnea have been identified as risk factors for the persistence of symptoms.


Assuntos
COVID-19 , Transtornos do Olfato , Estudos de Casos e Controles , Seguimentos , Humanos , Transtornos do Olfato/diagnóstico , Transtornos do Olfato/epidemiologia , Transtornos do Olfato/etiologia , SARS-CoV-2 , Distúrbios do Paladar/diagnóstico , Distúrbios do Paladar/epidemiologia , Distúrbios do Paladar/etiologia
12.
Laryngoscope ; 130(11): 2674-2679, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32686164

RESUMO

OBJECTIVE: To evaluate the incidence of certain symptoms in a population of health workers exposed to coronavirus disease 2019 patients. STUDY DESIGN: Case-control study. METHODS: The study was conducted at a tertiary care hospital from March 1 to April 7, 2020. Health workers with suspected coronavirus disease 2019 (COVID-19) infection were included. The presence of COVID-19 was detected by using real-time polymerase chain reaction (RT-PCR) methods. Positive and negative RT-PCR patients were used as case and control groups, respectively. This study analyzed the incidence of COVID-19 symptoms in both patient groups. Visual analog scales were used for self-assessment of smell and taste disorders, ranging from 0 (no perception) to 10 (excellent perception). RESULTS: There were 215 (60.6%) patients with positive RT-PCR and 140 (39.4%) patients with negative RT-PCR. The presence of symptoms such as hyposmia hypogeusia, dysthermia, and cough were strongly associated with a positive RT-PCR. The association of cough and subjective hyposmia had 5.46 times higher odds of having a positive test. The receiver operating characteristic (ROC) analysis showed that a fever higher than 37.45°C resulted in sensitivity and specificity of 0.65 and 0.61, respectively. A total of 138 cases (64.1%) and 114 cases (53%) had subjective hyposmia and hypogeusia, respectively. The 85.4% of these patients recovered olfactory function within the first 14 days of the onset of the symptoms. CONCLUSION: There is a significant association between positive RT-PCR and subjective hyposmia. The association of subjective hyposmia and cough increase significantly the odds of having a positive RT-PCR. The measurement of fever as the only method for screening of COVID-19 infection resulted in a poor association. LEVEL OF EVIDENCE: 3 Laryngoscope, 130:2674-2679, 2020.


Assuntos
Ageusia/epidemiologia , Anosmia/epidemiologia , COVID-19/complicações , Tosse/epidemiologia , SARS-CoV-2 , Adulto , Ageusia/virologia , Anosmia/virologia , Estudos de Casos e Controles , Tosse/virologia , Feminino , Pessoal de Saúde/estatística & dados numéricos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Curva ROC , Reação em Cadeia da Polimerase em Tempo Real , Sensibilidade e Especificidade
13.
Otolaryngol Head Neck Surg ; 163(3): 462-464, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32450761

RESUMO

During the SARS-CoV-2 pandemic, patients in intensive care units who are undergoing long-term intubation may require tracheostomy. There is controversy about indication and health care professionals' safety regarding the conventional or percutaneous technique. We performed a prospective analysis of a series of 27 consecutive patients with COVID-19 comparing both tracheostomy techniques, safety, and prognosis clinical markers. The results show that the techniques are equally safe, without cases of infection in surgeons. The Sequential Organ Failure Assessment score before surgery and the progression in ventilation support during the first 72 hours after tracheostomy are optimal prognostic markers for these patients.


Assuntos
Infecções por Coronavirus/terapia , Segurança do Paciente , Pneumonia Viral/terapia , Traqueostomia/métodos , Idoso , Betacoronavirus , COVID-19 , Feminino , Humanos , Unidades de Terapia Intensiva , Masculino , Escores de Disfunção Orgânica , Pandemias , Prognóstico , Estudos Prospectivos , SARS-CoV-2
14.
Rev. pediatr. electrón ; 17(1): 1-7, abr 2020.
Artigo em Espanhol | LILACS | ID: biblio-1099830

RESUMO

La enfermedad de Kawasaki (EK) es una vasculitis aguda de vaso mediano que afecta principalmente a niños menores de 5 años, que de no ser tratada, se asocia al desarrollo de aneurismas de las arterias coronarias en aproximadamente el 25% de los casos. Típicamente la EK se presenta con fiebre, cambios mucocutáneos y linfadenopatía. Sin embargo, EK es una enfermedad excepcional en la que las formas incompletas de la enfermedad son muy comunes y a menudo asociación sintomatologías atípicas. Éstas pueden crear un desafío diagnóstico para los tratantes y retrasar el inicio de la terapia. No existe un gold standard para el diagnóstico de EK pero hay estudios de laboratorio y hallazgos ecocardiográficos que permiten apoyar el diagnóstico en casos incompletos. El estudio con ecocardiograma debe realizarse lo más pronto posible cuando se sospecha el diagnóstico, pero no debe retrasar el inicio de tratamiento. El objetivo de la terapia en EK es disminuir el riesgo de desarrollar aneurismas de las arterias coronarias y de esta forma, la morbimortalidad asociada a dicha condición. El propósito de esta revisión es conocer las características clínicas y las posibles formas de presentación de esta patología, además del tratamiento actual.


Kawasaki disease (KD) is an acute vasculitis of the medium vessel that mainly affects children under 5 years old, which if it's not treated, is associated with the development of coronary artery aneurysms in approximately 25% of all cases. Typically, KD presents with fever, mucocutaneous changes and lymphadenopathy. However, EK is an exceptional disease in which incomplete forms of the disease are very common and atypical presentations often occur. These presentations may create a diagnostic puzzle for pediatricians and may delay the start of therapy. There is no specific study for the diagnosis of KD but there are laboratory studies and findings in ECG that support the diagnosis in atypical cases. The echocardiogram study should be performed as soon as possible when the diagnosis is suspected, but should not delay the treatment. The goal of treatment in KD is to reduce the risk of developing aneurysms of the coronary arteries and thereby decrease the morbidity and mortality associated with this condition.


Assuntos
Humanos , Lactente , Pré-Escolar , Criança , Síndrome de Linfonodos Mucocutâneos/diagnóstico , Ecocardiografia , Síndrome de Linfonodos Mucocutâneos/etiologia , Síndrome de Linfonodos Mucocutâneos/terapia
15.
Rev. pediatr. electrón ; 17(1): 1-6, abr 2020.
Artigo em Espanhol | LILACS | ID: biblio-1099831

RESUMO

La parotiditis es un infección viral producida por el virus parotídeo. Clínicamente se caracteriza por aumento de volumen de la glándula parótida generalmente bilateral. La estrategia que ha mostrado ser más eficaz para la prevención de esta infección ha sido la implementación de la vacuna tres vírica en los programas de inmunización. En países con población altamente inmunizada como Chile, se logró una importante disminución de la incidencia de esta enfermedad. Sin embargo, a pesar de la efectividad de la vacuna se siguen reportando brotes en todo el mundo, evidenciándose un cambio epidemiológico, trasladándose la edad de presentación clínica desde la niñez y adolescencia hacia los adultos jóvenes. Este aumento en el número de casos ha sido estudiado, determinando que el efecto protector inmunitario de la vacuna decaería con el transcurso del tiempo, contribuyendo a la propagación de los brotes. Con respecto a posibles estrategias para el manejo de los brotes la aplicación de una dosis adicional de la vacunas tres vírica en población expuesta sería una medida que mejoraría el control de los brotes.


Mumps is a viral infection caused by mumps virus. Clinically, it is characterized by increased parotid volume. The most effective strategy for preventing this infection, has been the implementation of measles-mumps-rubella (MMR) vaccine in the national immunization program. Among countries with a highly immunized population, like Chile, there has been an important reduction in the incidence of this disease. Nevertheless, despite the effectivity of the MMR, there are reports of outbreaks worldwide, with an epidemiological change, from clinical presentation in childhood, to adolescents and adults. This outbreaks have been studied, and it has been determined that they are due to the waning of vaccine-derived immunity. Regarding strategies for the management of new outbreaks, the administration of an additional dose of MMR, would be an alternative.


Assuntos
Humanos , Recém-Nascido , Lactente , Pré-Escolar , Criança , Adolescente , Parotidite/epidemiologia , Vacina contra Caxumba/uso terapêutico , Surtos de Doenças/prevenção & controle , Programas de Imunização , Vacina contra Sarampo-Caxumba-Rubéola/administração & dosagem , Vírus da Caxumba
16.
Appl Biochem Biotechnol ; 189(3): 903-918, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31144254

RESUMO

Interfacial esterases are useful enzymes in bioconversion and racemic mixture resolution processes. Marine invertebrates are few explored potential sources of these proteins. In this work, aqueous extracts of 41 species of marine invertebrates were screened for esterase, lipase, and phospholipase A activities, being all positive. Five extracts (Stichodactyla helianthus, Condylactis gigantea, Stylocheilus longicauda, Zoanthus pulchellus, and Plexaura homomalla) were selected for their activity values and immobilized on Octyl-Sepharose CL 4B support by interfacial adsorption. The selectivity of this immobilization method for interfacial esterases was evidenced by immobilization percentages ≥ 94% in almost all cases for lipase and phospholipase A activities. Six pharmaceutical-relevant esters (phenylethyl butyrate, ethyl-2-hydroxy-4-phenyl-butanoate, 2-oxyranylmethyl acetate (glycidol acetate), 7-aminocephalosporanic acid, methyl-prostaglandin F2α, and methyl-6-metoxy-α-methyl-2-naphtalen-acetate -naproxen methyl ester-) were bioconverted by at least three of these biocatalysts, with the lowest conversion percentage of 24%. In addition, three biocatalysts were used in the racemic mixture resolution of three previous compounds. The S. helianthus-derived biocatalyst showed the highest enantiomeric ratios for glycidol acetate (2.67, (S)-selective) and naproxen methyl ester (8.32, (R)-selective), and the immobilized extract of S. longicauda was the most resolutive toward the ethyl-2-hydroxy-4-phenyl-butanoate (8.13, (S)-selective). These results indicate the relevance of such marine interfacial esterases as immobilized biocatalysts for the pharmaceutical industry.


Assuntos
Organismos Aquáticos/enzimologia , Biocatálise , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Esterases/química , Esterases/metabolismo , Invertebrados/enzimologia , Animais , Ésteres/química , Ésteres/metabolismo , Lipase/metabolismo , Fosfolipases/metabolismo , Estereoisomerismo , Especificidade por Substrato , Água/química
17.
Otol Neurotol ; 40(1): 79-87, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30334870

RESUMO

OBJECTIVE: This study aimed to evaluate the changes in the VOR gain after intratympanic gentamicin therapy and to correlate them with the mid-term effects on the control of vertigo, in a population of Menière's disease patients. STUDY DESIGN: The study design was a prospective "Outcomes research." SETTING: Tertiary referral center. PATIENTS: This study included 20 patients with unilateral Menière's disease refractory to medical therapy for at least 1 year, and treated with an on demand intratympanic gentamicin protocol. INTERVENTION: Therapeutic. MAIN OUTCOME MEASURE: Audiometry, caloric testing, and a vHIT before beginning the protocol were performed. Patients underwent weekly vHIT assessments until a significant gain reduction was observed. Subsequently we performed vHIT tests 1 month after the therapy completion, and then every 3 months for at least 1 year. RESULTS: Complete vertigo control (class A) was achieved in 14 patients at the 12-month follow-up assessment. We observed a significant reduction in VOR gain values at the 3-week follow-up assessment. We found a significant correlation between the 1-month posttreatment ipsilateral hVOR gain and the rate of vertigo recurrence after the first IT gentamicin treatment (p = 0.012; r = 0.400). At the mid-term assessment, 10 patients exhibited a significant partial recovery of the hVOR gain. CONCLUSIONS: The delayed effect of intratympanic gentamicin and the subsequent gain restoration are factors that may influence the patients' outcome. The feasibility of the vHIT system makes it a useful tool to monitorize the VOR changes.


Assuntos
Antibacterianos/administração & dosagem , Gentamicinas/administração & dosagem , Doença de Meniere/tratamento farmacológico , Adulto , Idoso , Antibacterianos/uso terapêutico , Testes Calóricos , Feminino , Gentamicinas/uso terapêutico , Humanos , Injeção Intratimpânica , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
19.
Protein Expr Purif ; 95: 57-66, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24326193

RESUMO

Sticholysin I and Sticholysin II (StI and StII) are two potent hemolysins which form pores in natural and model membranes at nanomolar concentrations. These proteins were purified from the aqueous extract of the sea anemone Stichodactyla helianthus, Ellis 1768, by gel filtration and ionic exchange chromatography. This procedure rendered StI and StII with high purity (purification factors: 36 and 50, respectively) but a low yield of hemolytic activity, HA (<3%). Additionally, these toxins exhibited very low phospholipase activity (10(-3)U/mg of protein). In this work, a mixture StI-StII was obtained (yield >95%, with an increase in specific activity: 14 times) from the animal extract using an oxidized phospholipid-based affinity chromatographic matrix binding phospholipases. Cytolysin identification in the mixture was performed by immunoblotting and N-terminal sequence analyses. Phospholipase A2 (PLA2) activity of StI-StII was relatively high (1.85U/mg) and dependent of Ca(2+). The activity resulted optimum when was measured with the mostly unsaturated soybean phosphatidylcholine (PC), when compared to the less unsaturated egg PC or completely saturated dipalmitoyl PC, in the presence of 40mM Ca(2+) at pH 8.0. This Ca(2+) concentration did not exert any effect on binding of StI-StII with soybean PC monolayers. Then, PLA2 activity seems not be required to binding to membranes.


Assuntos
Venenos de Cnidários/metabolismo , Proteínas Hemolisinas/metabolismo , Fosfolipases A2/metabolismo , Anêmonas-do-Mar/química , Anêmonas-do-Mar/enzimologia , Sequência de Aminoácidos , Animais , Cálcio/metabolismo , Cromatografia de Afinidade , Venenos de Cnidários/química , Venenos de Cnidários/isolamento & purificação , Proteínas Hemolisinas/química , Proteínas Hemolisinas/isolamento & purificação , Dados de Sequência Molecular , Compostos Orgânicos/química , Compostos Orgânicos/isolamento & purificação , Compostos Orgânicos/metabolismo , Fosfolipases A2/química , Fosfolipases A2/isolamento & purificação , Alinhamento de Sequência
20.
J Biol Chem ; 287(19): 15427-38, 2012 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-22411994

RESUMO

This study describes a novel bifunctional metallocarboxypeptidase and serine protease inhibitor (SmCI) isolated from the tentacle crown of the annelid Sabellastarte magnifica. SmCI is a 165-residue glycoprotein with a molecular mass of 19.69 kDa (mass spectrometry) and 18 cysteine residues forming nine disulfide bonds. Its cDNA was cloned and sequenced by RT-PCR and nested PCR using degenerated oligonucleotides. Employing this information along with data derived from automatic Edman degradation of peptide fragments, the SmCI sequence was fully characterized, indicating the presence of three bovine pancreatic trypsin inhibitor/Kunitz domains and its high homology with other Kunitz serine protease inhibitors. Enzyme kinetics and structural analyses revealed SmCI to be an inhibitor of human and bovine pancreatic metallocarboxypeptidases of the A-type (but not B-type), with nanomolar K(i) values. SmCI is also capable of inhibiting bovine pancreatic trypsin, chymotrypsin, and porcine pancreatic elastase in varying measures. When the inhibitor and its nonglycosylated form (SmCI N23A mutant) were overproduced recombinantly in a Pichia pastoris system, they displayed the dual inhibitory properties of the natural form. Similarly, two bi-domain forms of the inhibitor (recombinant rSmCI D1-D2 and rSmCI D2-D3) as well as its C-terminal domain (rSmCI-D3) were also overproduced. Of these fragments, only the rSmCI D1-D2 bi-domain retained inhibition of metallocarboxypeptidase A but only partially, indicating that the whole tri-domain structure is required for such capability in full. SmCI is the first proteinaceous inhibitor of metallocarboxypeptidases able to act as well on another mechanistic class of proteases (serine-type) and is the first of this kind identified in nature.


Assuntos
Carboxipeptidases/metabolismo , Poliquetos/genética , Serina Proteases/metabolismo , Inibidores de Serina Proteinase/genética , Sequência de Aminoácidos , Animais , Aprotinina/química , Aprotinina/genética , Aprotinina/farmacologia , Sequência de Bases , Sítios de Ligação/genética , Biocatálise/efeitos dos fármacos , Carboxipeptidases/antagonistas & inibidores , Bovinos , Clonagem Molecular , Relação Dose-Resposta a Droga , Humanos , Cinética , Modelos Moleculares , Dados de Sequência Molecular , Peso Molecular , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacologia , Análise de Sequência de DNA , Inibidores de Serina Proteinase/química , Inibidores de Serina Proteinase/farmacologia
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