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1.
Artigo em Inglês | MEDLINE | ID: mdl-38465480

RESUMO

BACKGROUND: Genome diagnostics is considered gold standard diagnostics for epidermolysis bullosa (EB), a phenotypically and genetically heterogeneous group of rare disorders characterized by blistering and wounding of mucocutaneous tissues. EB is caused by pathogenic variants in genes encoding proteins of the dermo-epidermal junction. Accurate genetic diagnosis of EB is crucial for prognostication, counselling and precision-medicine. Genome diagnostics for EB started in 1991 with the introduction of Sanger sequencing (SS), analysing one gene at a time. In 2013, SS was superseded by next-generation sequencing (NGS), that allow for high-throughput sequencing of multiple genes in parallel. Several studies have shown a beneficial role for NGS in EB diagnostics, but its true benefit has not been quantified. OBJECTIVES: To determine the benefit of NGS in EB by systematically evaluating the performance of different genome diagnostics used over time based on robust data from the Dutch EB Registry. METHODS: The diagnostic performances of SS and NGS were systematically evaluated in a retrospective observational study including all index cases with a clinical diagnosis of EB in whom genome diagnostics was performed between 01 January 1994 and 01 January 2022 (n = 308), registered at the Dutch EB Expertise Centre. RESULTS: Over time, a genetic diagnosis was made in 289/308 (94%) EB cases. The diagnostic yield increased from 89% (SS) to 95% (NGS). Most importantly, NGS significantly reduced diagnostic turnaround time (39 days vs. 211 days, p < 0.001). The likelihood of detecting variants of uncertain significance and additional findings increased from 5% and 1% (SS) to 22% and 13% (NGS) respectively. CONCLUSIONS: Our study quantifies the benefit of NGS-based methods and demonstrate they have had a major impact on EB diagnostics through an increased diagnostic yield and a dramatically decreased turnaround time (39 days). Although our diagnostic yield is high (95%), further improvement of genome diagnostics is urgently needed to provide a genetic diagnosis in all EB patients.

2.
Sci Rep ; 11(1): 20453, 2021 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-34650072

RESUMO

While the cultivated area of pollinator-dependent crops is increasing, pollinator availability is decreasing, leading to problems in many agroecosystems. For this reason, pollinator-dependent crop growers often rent beehives to support their pollination requirements to sustain fruit productivity. However, the efficiency of those pollination systems has not been extensively studied. Here, we compared the effect of "precision" pollination (i.e., application of pesticides coordinated with growers, audit of hives, dietary supplementation and individual distribution of hives) with conventional practices (i.e., pesticides applications without coordination with growers and no audit of hives, low maintenance of hives and hives distributed in large groups) on the mean level of pollination and fruit production and quality in blueberry crops. In nine blueberry fields, we measured bee visitation rate to flowers, fruit set, fruit firmness and fruit weight. On average, precision-pollinated plots had 70% more bee visits to flowers and produced 13% more fruits that were 12% heavier and 12% firmer than those obtained through conventional practices. These results showed that pollination efficiency could be improved if key management related to bee strength, distribution and health care are taken into account. Due to these results, we encourage growers and beekeepers to include precision pollination practices to both increase the productivity of blueberry fields and the wellbeing of honey bees within agroecosystems.


Assuntos
Mirtilos Azuis (Planta) , Produção Agrícola/métodos , Polinização , Animais , Abelhas , Frutas
3.
J Mater Chem B ; 4(46): 7423-7428, 2016 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-32263743

RESUMO

Superoxide radicals are associated with the development of many severe diseases, such as cancer. Under nonpathogenic conditions, the natural enzyme superoxide dismutase (SOD) regulates the intracellular superoxide concentrations, but nearly all tumor tissues show reduced SOD levels. Selective imaging in early progression stages remains a key requirement for efficient cancer diagnosis and treatment. Magnetic resonance imaging (MRI) as a noninvasive tool with high spatial resolution may offer advantages here, but MRI contrast agents exhibiting a redox-triggered change in the image contrast towards superoxide radicals have not been reported so far. Here we show that manganese oxide (MnO) nanoparticles (NPs) exhibit an intrinsic SOD-like activity, which is higher than that of the native Mn-dependent SOD. In addition, MnO NPs significantly enhance the MRI contrast when exposed to superoxide radicals, making them responsive MRI contrast agents for the treatment and imaging of cancer cells with reduced SOD levels.

4.
J Eur Acad Dermatol Venereol ; 24(11): 1285-95, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20569284

RESUMO

BACKGROUND: Azzalure® (Galderma SA), a newly approved European botulinum neurotoxin type A (BoNT-A), is derived from Dysport™ (Ipsen Ltd.), which has a 20-year history of product consistency and has been widely used for various aesthetic and therapeutic applications. Azzalure® and Dysport™ are collectively referred to as BoNT-A (Speywood Unit) after the unit of their activity, and are distinct from other commercial BoNT-A preparations. Consensus has been developed for the treatment of upper facial wrinkles with BoNT-A (Speywood Unit). OBJECTIVE: To provide consensus recommendations on the treatment with BoNT-A (Speywood Unit) for wrinkles on the middle and lower face, neck and chest region. METHODS: The members of the International Board on Botulinum toxin Azzalure (IBBA) convened to develop consensus based on their extensive experience. RESULTS: The recommended final concentration of BoNT-A (Speywood Unit) is 200 Speywood Units/ml after reconstitution. The consensus recommendations were provided for nine indications, including lower eyelid wrinkles, bunny lines, drooping nasal tip, perioral wrinkles, masseter hypertrophy, drooping mouth corners, dimpled chin, platysmal bands and décolleté wrinkles. For each indication, anatomy of the region to be treated was discussed, as were potential side-effects. The consensus recommendations included the number and location of the injection points, dose range of each point and the total injection, as well as specific injection technique. CONCLUSION: These recommendations provide a guideline for physicians who wish to perform safe and efficacious treatment with BoNT-A (Speywood Unit) on the less commonly treated middle and lower face, neck and chest region.


Assuntos
Toxinas Botulínicas Tipo A/uso terapêutico , Técnicas Cosméticas/normas , Face , Guias de Prática Clínica como Assunto , Envelhecimento da Pele/efeitos dos fármacos , Humanos , Cooperação Internacional , Pescoço , Neurotoxinas/uso terapêutico , Tórax
5.
J Eur Acad Dermatol Venereol ; 24(11): 1278-84, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20337830

RESUMO

BACKGROUND: Azzalure (Galderma SA) is a newly approved European botulinum neurotoxin type A (BoNT-A). It is derived from Dysport (Ipsen Pharma), which has a long history of usages in various applications. Azzalure and Dysport are collectively referred to as BoNT-A (Speywood Unit) and are different from other BoNT-A preparations. OBJECTIVE: To provide consensus recommendations on the treatment of upper face wrinkles with BoNT-A (Speywood Unit). METHODS: The members of the International Board on Botulinum toxin Azzalure (IBBA) convened to develop consensus on the treatment of upper facial wrinkles based on their own extensive experience. RESULTS: The consensus recommendations address the general issues regarding treatment and provide specific guidelines on the anatomy, injection points, dose, injection technique and safety precautions concerning each common upper face indication. The recommended final concentration of BoNT-A (Speywood Unit) is 200 s.U/mL (10 s.U/0.05 mL) after reconstitution. For glabellar lines, the members recommend a total of five injection points with 10 s.U/point. For forehead wrinkles, the members recommend four to six injections into the frontalis with 5-10 s.U/point. For crow's feet, the members recommend three injections per side with 5-10 s.U/point at the lateral part of the orbicularis oculi. For lateral eyebrow lift, the members recommend one point at each eyebrow tail and an additional one in each side of the frontalis with 5-10 s.U/point. CONCLUSION: This guideline provides a framework for physicians who wish to perform safe and efficacious injection of BoNT-A (Speywood Unit).


Assuntos
Toxinas Botulínicas Tipo A/uso terapêutico , Técnicas Cosméticas/normas , Testa , Guias de Prática Clínica como Assunto , Envelhecimento da Pele/efeitos dos fármacos , Humanos , Cooperação Internacional , Neurotoxinas/uso terapêutico
7.
Hum Biol ; 77(5): 705-14, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16596947

RESUMO

The large heterogeneity in the cystic fibrosis (CF) gene is the main difficulty for genotype characterization. Numerous studies have reported considerable variations in frequencies of CF transmembrane conductance regulator (CFTR) mutations in different populations, such as African, Asian, or European populations. To completely characterize the spectrum of mutations in the CFTR gene in the Réunion Island population, we screened 228 CF chromosomes using denaturing high-pressure liquid chromatography and denaturing gradient gel electrophoresis following by direct sequencing. We identified 27 mutations, accounting for 93% of CF chromosomes. They included three novel mutations (M1T, 3121-3C-->G, and L1324P), which are described in this paper. The detection of such a high proportion of Réunion Island CFTR mutations is important for improving neonatal screening of CF on Réunion Island.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Fibrose Cística/genética , Genética Populacional , Triagem Neonatal , Polimorfismo Genético , Fibrose Cística/diagnóstico , Humanos , Recém-Nascido , Mutação , Reunião
9.
Curr Eye Res ; 16(5): 511-5, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9154391

RESUMO

PURPOSE: The lacrimal gland expresses nuclear retinoic acid receptors. This suggests that retinoids are involved in control of gene expression in the lacrimal gland. Retinoid X receptors (RXRs) form heterodimers with and are required for activation of retinoic acid receptors. The purpose of this study was to identify retinoid X receptors in the lacrimal gland. METHODS: Total RNA was purified from rat, rabbit and human lacrimal glands and from cultured rat lacrimal cells. RNA was analyzed by northern blotting using cDNA probes for RXR alpha, RXR beta and RXR gamma. Nuclear protein extracts from rat and rabbit lacrimal glands were probed for RXR beta by immunoblotting, using a mouse monoclonal antibody. RESULTS: RXR alpha mRNA transcripts (5 kb) and RXR beta mRNA transcripts (3.3 kb) are present in the lacrimal glands of all species studied and in cultured rat lacrimal cells. RXR gamma mRNA (1.9 kb) was detected only in the rabbit lacrimal gland. RXR beta is expressed as a 50 kDa protein in rat and rabbit lacrimal glands. CONCLUSIONS: This study confirms the presence of RXRs in the lacrimal gland, thereby supporting a role for retinoids and their nuclear receptors in the control of gene transcription in the lacrimal gland.


Assuntos
Aparelho Lacrimal/metabolismo , Proteínas Nucleares/metabolismo , Receptores do Ácido Retinoico/metabolismo , Fatores de Transcrição/metabolismo , Animais , Anticorpos Monoclonais , Northern Blotting , Células Cultivadas , Humanos , Isomerismo , Aparelho Lacrimal/citologia , Camundongos , Camundongos Endogâmicos BALB C , RNA Mensageiro/metabolismo , Coelhos , Ratos , Ratos Sprague-Dawley , Receptores do Ácido Retinoico/genética , Receptores X de Retinoides , Fatores de Transcrição/genética
10.
An Otorrinolaringol Ibero Am ; 16(6): 641-8, 1989.
Artigo em Espanhol | MEDLINE | ID: mdl-2624308

RESUMO

The meagre figures of malignancies in the outer canal, especially basal cell carcinoma, offer the AA. the opportunity of this communication. Owing to the small size of the growth it was successfully treated with X-ray therapy.


Assuntos
Carcinoma Basocelular/diagnóstico , Meato Acústico Externo , Neoplasias da Orelha/diagnóstico , Adulto , Biópsia , Carcinoma Basocelular/patologia , Carcinoma Basocelular/radioterapia , Meato Acústico Externo/patologia , Neoplasias da Orelha/patologia , Neoplasias da Orelha/radioterapia , Humanos , Masculino
12.
Biol Chem Hoppe Seyler ; 369(5): 397-401, 1988 May.
Artigo em Inglês | MEDLINE | ID: mdl-3166744

RESUMO

The effect of secondary-subsite interactions on the catalytic efficiency of horse urinary kallikrein was studied using as substrates oligopeptides and peptidyl-4-nitroanilides with L-Arg at P1. The known secondary specificity of tissue kallikreins for hydrophobic residues at P2 was also demonstrated for horse urinary kallikrein and a higher preference of this enzyme for L-Phe over L-Leu at P2 was evident. Interaction of subsites S3 with D-Pro and D-Phe enhanced the catalytic efficiency but tripeptidyl-4-nitroanilides with acetyl-D-Pro, L-Pro and acetyl-L-Pro at P3 were no better substrates than acetyl-dipeptidyl-4-nitroanilides. The importance of the leaving group for the catalysis was proved by higher kcat/Km values for the peptides in relation to peptidyl-4-nitroanilides containing a common acyl-chain. The low kcat value for the peptide with L-Pro at P'2 stresses the importance of a hydrogen bond between P'2 amide and the carbonyl group at S'2. One L-arginine residue at the leaving group, specially at the P'2 position, decreases the value of the apparent Km. This effect resulting of side-chain interactions with S'2, is impaired by a second L-Arg at P'1.


Assuntos
Calicreínas/urina , Animais , Sítios de Ligação , Cavalos , Calicreínas/isolamento & purificação , Cinética , Ligação Proteica , Especificidade por Substrato
13.
Biochemistry ; 26(16): 5032-5, 1987 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-3663643

RESUMO

Hydrolysis of several N alpha-substituted L-arginine 4-nitroanilides with porcine pancreatic kallikrein was studied under different conditions of pH, temperature, and salt concentration. At high substrate concentrations a deviation from Michaelis-Menten kinetics was observed with a significant increase in the hydrolysis rates of almost all substrates. Kinetic data were analyzed on the assumption that porcine pancreatic kallikrein presents an additional binding site with lower affinity for the substrate. Binding to this auxiliary site gives rise to a modulated enzyme species which can hydrolyze an additional molecule of the substrate through a second catalytic pathway. The values of both Michaelis-Menten and catalytic rate constants were higher for the modulated species than for the free enzyme, suggesting a mechanism of enzyme activation by substrate. Kinetic data indicated similar substrate requirements for binding at the primary and auxiliary sites of the enzyme. Tris(hydroxymethyl)aminomethane hydrochloride and NaCl were shown to alter the kinetic parameters of the hydrolysis of N alpha-acetyl-L-Phe-L-Arg 4-nitroanilide by porcine pancreatic kallikrein but not the enzyme activation pattern (ratio of the catalytic constants for the activated and the free enzyme forms). Similar observations were made when the hydrolysis of D-Val-L-Leu-L-Arg 4-nitroanilide was studied under different pH and temperature conditions.


Assuntos
Anilidas/metabolismo , Calicreínas/metabolismo , Oligopeptídeos/metabolismo , Pâncreas/enzimologia , Animais , Ativação Enzimática , Cinética , Especificidade por Substrato , Suínos , Termodinâmica
14.
Biol Chem Hoppe Seyler ; 367(3): 199-205, 1986 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3518738

RESUMO

The three tetrapeptides Ac-Phe-Arg-Arg-Val-NH2 (I), Ac-Phe-Arg-Arg-Pro-NH2 (II) and Ac-Phe-Lys-Arg-Val-NH2 (III) were shown to form a most convenient substrate system for the discrimination of the serine proteinases listed below. Tissue kallikreins (porcine pancreatic, horse and human urinary) have the unique feature of cleaving well the Arg-Arg bond in peptide I (P'2 = Val), hardly splitting it in peptide II (P'2 = Pro). The kcat/Km for the hydrolysis of peptide II by horse urinary kallikrein was 600-fold lower than that for peptide I. Trypsin, plasma kallikreins (human and rat), tonin and rat urinary kallikrein were distinguished from each other by the sequence of the N-terminal fragments formed in the hydrolysis of peptides I and/or II. Differences in the cleavage sites in these peptides are explained by differences in the specificities of the proteinase subsite S2 and/or in their preference for Arg or Lys residues. The three tetrapeptides were not substrates for plasmin.


Assuntos
Endopeptidases/metabolismo , Calicreínas/metabolismo , Oligopeptídeos/metabolismo , Tripsina/metabolismo , Sequência de Aminoácidos , Animais , Bovinos , Cavalos , Humanos , Ratos , Serina Endopeptidases , Especificidade da Espécie , Especificidade por Substrato , Suínos
15.
Adv Exp Med Biol ; 198 Pt A: 241-6, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3643710

RESUMO

The first purpose of this work was to obtain direct evidence that tissue kallikreins cleave arginyl bonds when the leaving group is Arg-Val, and on the contrary, do not split them when it is Arg-Pro; the second aim was to ascertain whether this specificity could be used as a criterion, for characterizing tissue kallikreins. Two tetrapeptides Ac-Phe-Arg-Arg-Val-NH2 and Ac-Phe-Arg-Arg-Pro-NH2 were synthesized by the solid phase method and purified to homogeneity. They were used as substrates for homogeneous preparations of tissue and plasma kallikreins, as well as for some related serine proteases. Products identification and kinetic analyses were made by HPLC.


Assuntos
Calicreínas/metabolismo , Oligopeptídeos/metabolismo , Sequência de Aminoácidos , Animais , Humanos , Hidrólise , Indicadores e Reagentes , Oligopeptídeos/síntese química , Ratos , Especificidade por Substrato
17.
Biochem Biophys Res Commun ; 112(2): 366-71, 1983 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-6552186

RESUMO

Homogeneous preparations of two well-characterized glandular kallikreins have been examined for their ability to hydrolyze BAM 22P, a methionine-enkephalin-containing-peptide found in the adrenal medulla. Both enzymes cleaved preferentially the Arg6-Arg7 bond in this substrate. The specificity constant (kcat/Km) for this cleavage was 86 mM-1 sec-1 for horse urinary kallikrein and 566 mM-1 sec-1 for porcine pancreatic kallikrein. These results demonstrate a previously undescribed specificity for glandular kallikreins and suggest a possible role for these widely distributed enzymes in prohormone processing.


Assuntos
Encefalina Metionina/análogos & derivados , Calicreínas/fisiologia , Precursores de Proteínas/metabolismo , Animais , Encefalina Metionina/metabolismo , Cavalos , Hidrólise , Calicreínas/urina , Cinética , Pâncreas/enzimologia , Especificidade por Substrato , Suínos
18.
Hoppe Seylers Z Physiol Chem ; 362(3): 337-45, 1981 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6785181

RESUMO

The synthetic tridecapeptide Gly-Leu-Met-Lys-Arg-Pro-Pro-Gly-Phe-Ser-Pro-Phe-Arg was used as a model substrate for horse urinary and porcine pancreatic kallikreins. The Met-Lys bond is hydrolyzed selectively by both enzymes. Oxidation of the methionine residue to sulfoxide made the peptide resistant to both kallikreins. Substitution of either the methionine or lysine residues by norleucine led to peptides in which the Nle-Lys or the Met-Nle bonds, respectively, were susceptible to the urinary kallikrein. The esterolytic and Met-Lys bond-splitting activities of both enzymes were inhibited similarly by phenylmethanesulfonyl fluoride. Both activities of the pancreatic kallikrein were inhibited by the chloromethane derivative Ala-Leu-Lys-CH2Cl. Inhibition by benzamidine of Met-Lys hydrolysis by both kallikreins was observed.


Assuntos
Bradicinina/análogos & derivados , Calicreínas/metabolismo , Peptídeos/metabolismo , Animais , Fenômenos Químicos , Química , Cavalos , Hidrólise , Lisina , Metionina , Oxirredução , Suínos
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