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1.
PLoS Pathog ; 18(2): e1010332, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35180277

RESUMO

Cassava brown streak disease (CBSD), dubbed the "Ebola of plants", is a serious threat to food security in Africa caused by two viruses of the family Potyviridae: cassava brown streak virus (CBSV) and Ugandan (U)CBSV. Intriguingly, U/CBSV, along with another member of this family and one secoviridae, are the only known RNA viruses encoding a protein of the Maf/ham1-like family, a group of widespread pyrophosphatase of non-canonical nucleotides (ITPase) expressed by all living organisms. Despite the socio-economic impact of CDSD, the relevance and role of this atypical viral factor has not been yet established. Here, using an infectious cDNA clone and reverse genetics, we demonstrate that UCBSV requires the ITPase activity for infectivity in cassava, but not in the model plant Nicotiana benthamiana. HPLC-MS/MS experiments showed that, quite likely, this host-specific constraint is due to an unexpected high concentration of non-canonical nucleotides in cassava. Finally, protein analyses and experimental evolution of mutant viruses indicated that keeping a fraction of the yielded UCBSV ITPase covalently bound to the viral RNA-dependent RNA polymerase (RdRP) optimizes viral fitness, and this seems to be a feature shared by the other members of the Potyviridae family expressing Maf/ham1-like proteins. All in all, our work (i) reveals that the over-accumulation of non-canonical nucleotides in the host might have a key role in antiviral defense, and (ii) provides the first example of an RdRP-ITPase partnership, reinforcing the idea that RNA viruses are incredibly versatile at adaptation to different host setups.


Assuntos
Manihot , Potyviridae , Manihot/genética , Nucleotídeos , Doenças das Plantas , Potyviridae/genética , Pirofosfatases , RNA Viral/análise , RNA Viral/genética , RNA Polimerase Dependente de RNA , Espectrometria de Massas em Tandem
2.
Handb Exp Pharmacol ; 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38418668

RESUMO

Bacterial infections are a significant public health concern, and the emergence of antibiotic-resistant bacteria (ARB) has become a major challenge for modern medicine. The overuse and misuse of antibiotics have contributed to the development of ARB, which has led to the need for alternative therapies. Plant-derived natural products (PNPs) have been extensively studied for their potential as alternative therapies for the treatment of bacterial infections. The diverse chemical compounds found in plants have shown significant antibacterial properties, making them a promising source of novel antibacterial agents. The use of PNPs as antibacterial agents is particularly appealing because they offer a relatively safe and cost-effective approach to the treatment of bacterial infections. This chapter aims to provide an overview of the current state of research on PNPs as antibacterial agents. It will cover the mechanisms of action of the main PNPs against bacterial pathogens and discuss their potential to be used as complementary therapies to combat ARB. This chapter will also highlight the most common screening methodologies to discover new PNPs and the challenges and future prospects in the development of these compounds as antibacterial agents.

3.
Sensors (Basel) ; 24(9)2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38732845

RESUMO

Metallic nanoscale particles attract a growing interest in several fields, thanks to their unique bonding characteristics; applications are appearing in the literature in the fields of, for example, sensor coatings and biochemical compound detection. However, the controlled fabrication of such nanopowders is often cumbersome, especially because their characterization is normally slow, involving procedures such as electron microscopy. On the other hand, microwave sensors based on near-field effects on materials are being developed with high sensitivity and show promising characteristics. In this paper, the authors show how a microwave sensor based on a Square Spiral Resonator can be used to characterize paraffin dispersions of nanoparticles conveniently and cost-effectively.

4.
Ultraschall Med ; 44(2): e118-e125, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34820795

RESUMO

PURPOSE: High-frequency ultrasound allows the accurate identification of neurofibromas in neurofibromatosis type 1 (NF1). This study aimed to analyze the ultrasound features of neurofibromas in children with NF1, to establish a classification based on the clinical and sonographic patterns of the different types of neurofibromas, and to evaluate the interobserver correlation coefficient (κ) of this classification. MATERIALS AND METHODS: In this prospective, single referral center observational study, clinical and ultrasound findings of neurofibromas in children diagnosed with NF 1 were analyzed. To identify the ultrasound patterns, a cluster analysis allowing the inclusion of both clinical and ultrasound data was designed. The κ coefficient was calculated using 9 external evaluators. RESULTS: 265 ultrasound scans were performed on a total of 242 neurofibromas from 108 children diagnosed with NF1. Cluster analysis allowed the identification of 9 patterns (Snedecor's F, P < 0.001) classified as "classic" cutaneous neurofibroma, blue-red neurofibroma, pseudoatrophic neurofibroma, nodular subcutaneous neurofibroma, diffuse subcutaneous neurofibroma, congenital cutaneous neurofibroma, congenital plexiform neurofibroma, congenital diffuse and plexiform neurofibroma, and subfascial neurofibroma. The κ coefficient of the interobserver ratings was 0.82. CONCLUSION: Patterns identified in the cluster analysis allow neurofibromas to be classified with a very high interobserver correlation.


Assuntos
Neurofibroma Plexiforme , Neurofibroma , Neurofibromatose 1 , Criança , Humanos , Neurofibromatose 1/diagnóstico por imagem , Neurofibroma Plexiforme/diagnóstico por imagem , Estudos Prospectivos , Neurofibroma/diagnóstico por imagem , Análise por Conglomerados
5.
Sensors (Basel) ; 23(8)2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37112281

RESUMO

Glycerin is a versatile organic molecule widely used in the pharmaceutical, food, and cosmetic industries, but it also has a central role in biodiesel refining. This research proposes a dielectric resonator (DR) sensor with a small cavity to classify glycerin solutions. A commercial VNA and a novel low-cost portable electronic reader were tested and compared to evaluate the sensor performance. Within a relative permittivity range of 1 to 78.3, measurements of air and nine distinct glycerin concentrations were taken. Both devices achieved excellent accuracy (98-100%) using Principal Component Analysis (PCA) and Support Vector Machine (SVM). In addition, permittivity estimation using Support Vector Regressor (SVR) achieved low RMSE values, around 0.6 for the VNA dataset and between 1.2 for the electronic reader. These findings prove that low-cost electronics can match the results of commercial instrumentation using machine learning techniques.

6.
Int J Mol Sci ; 24(7)2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-37047073

RESUMO

N-type voltage-gated calcium channel controls the release of neurotransmitters from neurons. The association of other voltage-gated calcium channels with epilepsy is well-known. The association of N-type voltage-gated calcium channels and pain has also been established. However, the relationship between this type of calcium channel and epilepsy has not been specifically reviewed. Therefore, the present review systematically summarizes existing publications regarding the genetic associations between N-type voltage-dependent calcium channel and epilepsy.


Assuntos
Canais de Cálcio Tipo N , Epilepsia , Síndromes Epilépticas , Humanos , Cálcio/metabolismo , Epilepsia/genética , Neurônios/metabolismo
7.
Int J Mol Sci ; 24(4)2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36834716

RESUMO

Drug-drug salts are a kind of pharmaceutical multicomponent solid in which the two co-existing components are active pharmaceutical ingredients (APIs) in their ionized forms. This novel approach has attracted great interest in the pharmaceutical industry since it not only allows concomitant formulations but also has proved potential to improve the pharmacokinetics of the involved APIs. This is especially interesting for those APIs that have relevant dose-dependent secondary effects, such as non-steroidal anti-inflammatory drugs (NSAIDs). In this work, six multidrug salts involving six different NSAIDs and the antibiotic ciprofloxacin are reported. The novel solids were synthesized using mechanochemical methods and comprehensively characterized in the solid state. Moreover, solubility and stability studies, as well as bacterial inhibition assays, were performed. Our results suggest that our drug-drug formulations enhanced the solubility of NSAIDs without affecting the antibiotic efficacy.


Assuntos
Ciprofloxacina , Sais , Ciprofloxacina/química , Composição de Medicamentos , Solubilidade , Sais/química , Anti-Inflamatórios não Esteroides , Antibacterianos , Preparações Farmacêuticas
8.
Pediatr Emerg Care ; 38(2): e731-e733, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33394949

RESUMO

OBJECTIVE: To determine the motions produced during pediatric extrication when using a system of motion estriction and extrication. METHODS: Simulation-based biomechanical analysis study conducted with inertial sensors to measure motion produced in the cervical spine of a pediatric simulator during extrication from a vehicle. RESULTS: The mean of the movements was 3.5° (SD ±1.35°). The mean time was 4 minutes 1 second (SD, ±45.09 seconds). The mean rotation toward the right was 3.34° (SD ±3.52°) and toward the left 2.62° (SD ±2.26°). The mean for lateralization was 6.24° (SD ±3.20°) toward the right and 2.50° (DE ±2.76°) toward the left. The mean for flexion was 2.36° (SD ±2.10°) and for extension 4.21° (SD ±2.15°). CONCLUSIONS: The device analyzed allows for the extrication of the pediatric patient with high levels of motion restriction of the spinal column with the Pediatric Immobilization and Extrication System.


Assuntos
Vértebras Cervicais , Imobilização , Criança , Humanos , Movimento , Amplitude de Movimento Articular , Rotação
9.
Int J Mol Sci ; 23(9)2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-35563270

RESUMO

Epilepsy is a neurological disorder that affects more than 50 million people. Its etiology is unknown in approximately 60% of cases, although the existence of a genetic factor is estimated in about 75% of these individuals. Hundreds of genes involved in epilepsy are known, and their number is increasing progressively, especially with next-generation sequencing techniques. However, there are still many cases in which the results of these molecular studies do not fully explain the phenotype of the patients. Somatic mutations specific to brain tissue could contribute to the phenotypic spectrum of epilepsy. Undetectable in the genomic DNA of blood cells, these alterations can be identified in cell-free DNA (cfDNA). We aim to review the current literature regarding the detection of somatic variants in cfDNA to diagnose refractory epilepsy, highlighting novel research directions and suggesting further studies.


Assuntos
Ácidos Nucleicos Livres , Epilepsia Resistente a Medicamentos , Epilepsia , Encéfalo , Ácidos Nucleicos Livres/sangue , Ácidos Nucleicos Livres/genética , Epilepsia Resistente a Medicamentos/diagnóstico , Epilepsia Resistente a Medicamentos/genética , Epilepsia/diagnóstico , Epilepsia/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Mutação
10.
Bull Hist Med ; 96(3): 403-430, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36571188

RESUMO

The medical auxiliary Mahboub al-Mahmoud (Tangier, 1888-ca. 1970) remains a neglected figure in the history of Morocco's medical modernization. However, his life and professional trajectory can provide a fruitful standpoint from which to question the persisting nationalist bias that has pervaded the modest postcolonial medical historiography about that farthest corner of North Africa. Mahboub's multiple mobilities-temporal, social, geographical, professional-transcend the "colonial fractures" created by the complex European partition of Morocco, which have resulted in Moroccans playing no significant role in the narratives of the origin and development of modern medicine in the country. This paper is divided into three sections, each of which deals with a distinctive phase of Mahboub's itinerary, his connections with various groups of irregular medical practitioners, and the modernizing initiatives they embodied from the times of Hassan I's late nineteenth-century reforms to the rise of Moroccan anticolonial nationalism in the 1930s.


Assuntos
Medicina , Humanos , História do Século XX , Marrocos , Medicina/tendências
11.
J Dtsch Dermatol Ges ; 19(1): 73-80, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33448128

RESUMO

BACKGROUND AND OBJECTIVE: Clinicopathological features of cutaneous neurofibromas presenting as large irregularly shaped congenital café-au-lait macules (CALM) in Neurofibromatosis type 1 (NF1) patients have not been well characterized. We aimed to analyze the histopathological findings of large "atypical" CALM in children with NF1. PATIENTS AND METHODS: In this retrospective observational study we analyzed histopathological and immunostaining features of 21 biopsy specimens from 18 large hyperpigmented macules with irregular borders with or without hypertrichosis present during the first months of life in NF1 diagnosed children. RESULTS: Of the 21 biopsies, ten showed a diffuse neurofibroma pattern and four exhibited characteristics of plexiform neurofibroma (PNF). In twelve specimens we observed groups of fusiform cells arranged linearly mimicking a small caliber nerve trunk with abnormal morphology. Repeated biopsies from two of these lesions performed at different ages showed transformation to a plexiform pattern. An increased interstitial cellularity was observed in 17 samples that was more evident around eccrine glands in 16 or accompanying hair follicles and vascular structures in twelve samples. All these cells had immunoreactivity for S100-protein, CD68 and were Melan-A positive in 15 samples. CONCLUSION: Clinicopathological findings of congenital cutaneous neurofibromas provide early diagnostic clues of NF1 with high relevance for monitoring of these patients.


Assuntos
Neurofibromatose 1 , Neoplasias Cutâneas , Manchas Café com Leite/diagnóstico , Criança , Humanos , Lactente , Neurofibroma , Neurofibromatose 1/diagnóstico , Estudos Retrospectivos , Neoplasias Cutâneas/diagnóstico
12.
Clin Exp Allergy ; 50(12): 1352-1361, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32946612

RESUMO

BACKGROUND: In allergology, the intradermal approach is generally used to establish an aetiological diagnosis, with limited experience in specific allergen immunotherapy. OBJECTIVE: To evaluate the efficacy and safety of immunotherapy with an allergen extract of glutaraldehyde-polymerized Phleum pratense, administered intradermally, in patients with rhinoconjunctivitis sensitized to grass pollen. METHODS: Multicentre, randomized, double-blind, placebo-controlled clinical trial in patients from 12 to 65 years of age with rhinitis or rhinoconjunctivitis, with or without asthma, due to grass pollen allergy. Patients were divided into three groups and received a total of six doses in a weekly interval, of either placebo; 0.03 or 0.06 µg of protein per dose of P pratense allergoid. The primary objective was to evaluate the combined symptoms and medication consumption score (CSMS). The secondary objectives were symptoms and medication, tolerance to the conjunctival provocation test, specific IgE and IgG4 antibodies and the safety profile according to the WAO scale. RESULTS: The dose of 0.06 µg of protein proved to be effective versus the placebo by significantly reducing CSMS and increasing tolerance to the allergenic extract in the conjunctival provocation test, after the first pollen season. This group showed a significant reduction in specific IgE after the second pollen season relative to the baseline. There were no variations in IgG4 levels. Only one grade 2 systemic reaction was recorded. CONCLUSION & CLINICAL RELEVANCE: Intradermal immunotherapy with P pratense allergoid has been shown to be effective and safe, reducing CSMS, increasing tolerance to the conjunctival provocation test and reducing IgE levels.


Assuntos
Alérgenos/administração & dosagem , Conjuntivite Alérgica/terapia , Dessensibilização Imunológica , Phleum/imunologia , Proteínas de Plantas/administração & dosagem , Pólen/imunologia , Rinite Alérgica Sazonal/terapia , Adolescente , Adulto , Alérgenos/imunologia , Biomarcadores/sangue , Conjuntivite Alérgica/diagnóstico , Conjuntivite Alérgica/imunologia , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos , Tolerância Imunológica/efeitos dos fármacos , Imunoglobulina E/sangue , Imunoglobulina G/sangue , Injeções Intradérmicas , Masculino , Pessoa de Meia-Idade , Proteínas de Plantas/imunologia , Rinite Alérgica Sazonal/diagnóstico , Rinite Alérgica Sazonal/imunologia , Espanha , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
13.
Med Confl Surviv ; 36(1): 61-81, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31852278

RESUMO

Emily Keene (London 1849 - Tangier 1941) became a relevant figure in pre-colonial Moroccan history due to her involvement in British policy and to her philanthropic-medical initiatives during the late 19th and early 20th centuries. Such prominence was closely linked with her marriage to the sheriff of Wazzan, a powerful spiritual and political figure. 'Grace', in a triple romantic, political and religious sense, was a defining feature of Keene's marriage and widowhood and explained that, despite her continuing adscription to Christian religion, British imperialism and Western science, she deployed a weakly hegemonic stand towards her country of adoption. This attitude distanced her from the 'civilizing mission' policy that set off in the mid-1880s and from the active proselytising and scientific supremacism of the British missionaries during the same period. After her husband's death in 1892, she showed a strong commitment towards (Western-style) Moroccan social and political emancipation, which she tried to promote in close association with a small circle of women friends and Quakers based in Tangiers. Emily Keene's is thus an excellent case study for exploring the interplay between gender, imperialism and religion in pre-colonial Morocco and also the connection between private life and public activity in 19th century women humanitarians.


Assuntos
Altruísmo , Cristianismo/história , Feminismo/história , Colonialismo/história , Feminino , História do Século XIX , História do Século XX , Humanos , Islamismo/história , Missionários/história , Marrocos , Reino Unido
14.
Int J Mol Sci ; 20(8)2019 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-31014011

RESUMO

Annona purpurea, known in Mexico as "cabeza de negro" or "ilama", belongs to the Annonaceae family. Its roots are employed in folk medicine in several regions of Mexico. Taking that information into account, a chemical and biological analysis of the components present in the roots of this species was proposed. Our results demonstrated that the dichloromethane (DCM) extract was exclusively constituted by a mixture of five new acetogenins named annopurpuricins A-E (1-5). These compounds have an aliphatic chain of 37 carbons with a terminal α,ß unsaturated γ-lactone. Compounds 1 and 2 belong to the adjacent bis-THF (tetrahydrofuran) α-monohydroxylated type, while compounds 3 and 4 belong to the adjacent bis-THF α,α'-dihydroxylated type; only compound 5 possesses a bis-epoxide system. Complete structure analysis was carried out by spectroscopy and chemical methods. All compounds were evaluated for their antiproliferative activity on three human tumor cell lines (MSTO-211H, HeLa and HepG2). Compounds 1-4 inhibited significantly the growth of HeLa and HepG2 cells, showing GI50 values in the low/subnanomolar range, while 5 was completely ineffective under the tested conditions. The investigation of the mechanism of action responsible for cytotoxicity revealed for the most interesting compound 1 the ability to block the complex I activity on isolated rat liver mitochondria (RLM).


Assuntos
Acetogeninas/química , Annona/química , Raízes de Plantas/química , Acetogeninas/isolamento & purificação , Acetogeninas/farmacologia , Animais , Annona/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Espectroscopia de Ressonância Magnética , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/metabolismo , Conformação Molecular , Raízes de Plantas/metabolismo , Ratos
18.
Pediatr Dermatol ; 34(3): 271-276, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28318056

RESUMO

BACKGROUND/OBJECTIVES: Mosaic neurofibromatosis type 1 (MNF1) is a variant of neurofibromatosis type 1 (NF1) in which clinical manifestations are limited to one or several body segments. The objective was to characterize the cutaneous features and associated systemic findings in a cohort of children with MNF1. METHODS: We performed a retrospective study of 40 children diagnosed with MNF1 at the Department of Dermatology, Hospital Infantil Niño Jesús, Madrid, Spain, from January 1, 1986, to October 31, 2015. RESULTS: All patients had pigmentary changes, alone (n = 39) or in combination with neurofibromas (n = 1). Twenty-four cases fulfilling the definition of MNF1 had six or more café au lait spots with or without freckling within the affected segment. They all lacked any other National Institutes of Health criteria of NF1. No patient had juvenile xanthogranuloma (JXG) or nevus anemicus (NA). Two children with MNF1 had epilepsy and two others developed malignancy (Hodgkin's lymphoma and ganglioneuroblastoma). CONCLUSIONS: Pigmentary changes are the most frequent presentation of MNF1 in children. MNF1 must be considered with segmentary distribution of freckling and café au lait spots. Other frequent cutaneous findings in NF1, such as JXG or NA, seem to be exceptional in MNF1. Although the possibility of systemic complications and cancer risk seem to be low, patients must be followed up.


Assuntos
Neurofibromatose 1/diagnóstico , Dermatopatias/etiologia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Estudos Retrospectivos , Espanha
19.
Sensors (Basel) ; 17(4)2017 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-28350356

RESUMO

In the last years, many passive electromagnetic sensors have been reported. Some of these sensors are used for measuring harmful substances. Moreover, the response of these sensors is usually obtained with laboratory equipment. This approach highly increases the total cost and complexity of the sensing system. In this work, a novel low-cost and portable Internet-of-Things (IoT) reader for passive wireless electromagnetic sensors is proposed. The reader is used to interrogate the sensors within a short-range wireless link avoiding the direct contact with the substances under test. The IoT functionalities of the reader allows remote sensing from computers and handheld devices. For that purpose, the proposed design is based on four functional layers: the radiating layer, the RF interface, the IoT mini-computer and the power unit. In this paper a demonstrator of the proposed reader is designed and manufactured. The demonstrator shows, through the remote measurement of different substances, that the proposed system can estimate the dielectric permittivity. It has been demonstrated that a linear approximation with a small error can be extracted from the reader measurements. It is remarkable that the proposed reader can be used with other type of electromagnetic sensors, which transduce the magnitude variations in the frequency domain.

20.
Dermatol Online J ; 23(11)2017 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-29447642

RESUMO

Bazex syndrome (BS) is a rare paraneoplastic syndrome most frequently associated with squamous cell carcinomas of the upper aerodigestive tractand other tumours. Characteristically, cutaneous lesions precede the diagnosis of malignancy. We report a 72-year-old patient with 1-year history of acral dermatitis. The diagnosis of BS was based on the presence of psoriasiform acral dermatitis and the evidence of two simultaneous tumors (prostate adenocarcinoma and undifferentiated carcinoma ofthe submandibular gland). It is important to have this syndrome in mind since cutaneous features usually precede an underlying neoplasm.


Assuntos
Carcinoma Basocelular/patologia , Hipotricose/patologia , Síndromes Paraneoplásicas/patologia , Neoplasias Cutâneas/patologia , Pele/patologia , Adenocarcinoma/complicações , Idoso , Biópsia , Carcinoma Basocelular/etiologia , Humanos , Hipotricose/etiologia , Masculino , Neoplasias Primárias Múltiplas/complicações , Síndromes Paraneoplásicas/etiologia , Neoplasias da Próstata/complicações , Neoplasias Cutâneas/etiologia , Neoplasias da Glândula Submandibular/complicações
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