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1.
Rev. Fac. Med. UNAM ; 66(6): 17-21, nov.-dic. 2023. graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1535222

RESUMO

Resumen Introducción: El pseudotumor inflamatorio ocular asociado a IgG4 es un proceso inflamatorio no neoplásico y poco frecuente con una incidencia de 0.28-1.08 por cada 100,000 personas. El diagnóstico de esta patología es de exclusión debiendo cumplir criterios histopatológicos, agrandamiento de un órgano en específico y concentraciones serias de IgG4. El tratamiento tiene como objetivo evitar las complicaciones secundarias. Caso clínico: Mujer de 54 años de edad sin patologías previas referidas, acude refiriendo que 6 meses previos presenta de forma súbita y sin causa aparente prurito a nivel de globo ocular y párpado izquierdo, además de disminución de la agudeza visual y dolor retroocular, motivo por el que acude a valoración. Al examen físico presentó movimientos oculares normales, proptosis izquierda, dolor a la palpación, hiperemia subconjuntival, opacidad corneal, ausencia de reflejo rojo y más renitente a la presión el ojo izquierdo en relación con el contralateral. Tomografía cráneo-toraco-abdominal reporta a nivel ocular izquierdo imágenes sugestivas de melanoma coroideo sin hallazgos de actividad metastásica. Se realiza enucleación de ojo izquierdo. Se envía pieza a patología la cual reporta infiltrado difuso linfoplasmocítico positivas para IgG4. Conclusión: La enfermedad por IgG4 ocular es una patología muy infrecuente de clínica inespecífica y diagnóstico complejo. Sin embargo, un abordaje rápido y correcto es fundamental para evitar complicaciones.


Abstract Introduction: IgG4-associated ocular inflammatory pseudotumor is a rare, non-neoplastic inflammatory process with an incidence of 0.28-1.08 per 100,000 people. The diagnosis of this pathology is one of exclusion, having to meet histopathological criteria, enlargement of a specific organ, and serious concentrations of IgG4. Treatment aims to avoid secondary complications. Clinical case: A 54-year-old woman with no previous reported pathologies, reports that for the past 6 months she has itching at the level of the eyeball and the left eyelid, suddenly and without apparent cause, in addition to decreased visual acuity and retro-ocular pain; this is why she asked for the evaluation. The physical examination revealed normal eye movements, left proptosis, pain on palpation, subconjunctival hyperemia, corneal opacity, absence of red reflex, and the left eye being more resistant to pressure in relation to the contralateral eye. The cranio-thoraco-abdominal tomography reported images at the left ocular level that were suggestive of choroidal melanoma without findings of metastatic activity. Enucleation of the left eye was performed. The specimen was sent to pathology which reported diffuse lymphoplasmacytic infiltrate positive for IgG4. Conclusion: Ocular IgG4 disease is a very rare pathology with non-specific symptoms and complex diagnosis. However, a quick and correct approach is essential to avoid complications.

2.
Rev. Fac. Med. UNAM ; 66(6): 29-34, nov.-dic. 2023. graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1535224

RESUMO

Resumen La isquemia mesentérica aguda se asocia a una mortalidad de entre el 50 y el 100%, la causa más rara de esta es la trombosis venosa de los vasos mesentéricos (5%) y portal (1%). Las manifestaciones clínicas son diversas, siendo el dolor abdominal el principal síntoma. La tomografía computarizada con contraste intravenoso en fase portal es la imagen más precisa para el diagnóstico. El tratamiento en fase aguda se basa en anticoagulación, fluidos intravenosos, antibióticos profilácticos, descanso intestinal y descompresión. La laparotomía de control de daños, incluida la resección intestinal y el abdomen abierto, pueden estar justificados en última instancia para pacientes con necrosis intestinal y sepsis. Caso clínico: Hombre de 35 años, sin antecedentes de importancia, solo tabaquismo desde hace 15 años. Refirió que 5 días previos comenzó a presentar dolor en el epigastrio tipo cólico, de intensidad moderada, posteriormente refirió que el dolor se generalizó y aumentó de intensidad, acompañado de náusea, vómito, intolerancia a la vía oral y alza térmica. Al examen físico tuvo datos de respuesta inflamatoria sistémica, estaba consciente y orientado, con abdomen doloroso a la palpación superficial y profunda a nivel generalizado, pero acentuado en el flanco derecho, rebote positivo con resistencia, timpanismo generalizado, peristalsis ausente. Se ingresó a quirófano a laparotomía exploradora, encontrando lesión a intestinal isquémica-necrótica a 190-240 cm del ángulo de Treitz, y 400 cc de líquido hemático; se realizó resección de la parte intestinal afectada, con entero-enteroanastomosis término-terminal manual. Se envió pieza a patología, y se reportó un proceso inflamatorio agudo con necrosis transmural y congestión vascular. Ante estos hallazgos se realizó angiotomografía abdominal que reportó defecto de llenado en la vena mesentérica superior, secundario a trombosis que se extendía hasta la confluencia y la vena porta. Conclusión: La trombosis venosa mesentérica y portal es una patología muy infrecuente en pacientes jóvenes sin factores de riesgo en los que se presenta dolor abdominal. El diagnóstico es complejo debido a que los datos clínicos y de laboratorio son poco específicos. Sin embargo, debemos tenerla en cuenta en el diagnóstico diferencial de etiologías de dolor abdominal.


Abstract Acute Mesenteric Ischemia is associated with a mortality rate between 50% and 100%; the rarest cause of this is venous thrombosis of the mesenteric (5%) and portal (1%) vessels. The clinical manifestations are diverse, with abdominal pain being the main symptom. Computed tomography with intravenous contrast in the portal phase is the most accurate image for diagnosis. Treatment in the acute phase is based on anticoagulation, intravenous fluids, prophylactic antibiotics, intestinal rest, and decompression. Damage control laparotomy, including bowel resection and open abdomen, may ultimately be warranted for patients with bowel necrosis and sepsis. Clinical case: 35-year-old man, with no significant history, only smoking for 15 years. For 5 days before, he reported crampy epigastric pain of moderate intensity. He subsequently reported that the pain became generalized and increased in intensity, accompanied by nausea, vomiting, oral intolerance, and temperature rise. The physical examination showed signs of a systemic inflammatory response, conscious and oriented, abdomen painful on superficial and deep palpation at a generalized level but accentuated on the right flank, positive rebound with resistance, generalized tympanism, absent peristalsis. The operating room was entered for exploratory laparotomy, finding an ischemic-necrotic intestinal lesion at 190 - 240 cm from the angle of Treitz, and 400cc of blood fluid. Resection of the affected intestinal part is performed, with entire manual terminal end anastomosis. The specimen was sent to pathology, reporting an acute inflammatory process with transmural necrosis and vascular congestion. Given these findings, abdominal CT angiography was performed, which reported a filling defect in the superior mesenteric vein, secondary to thrombosis that extended to the confluence and the portal vein. Conclusion: Mesenteric and portal venous thrombosis is a very rare pathology in young patients without risk factors in whom abdominal pain occurs. The diagnosis is complex because the clinical and laboratory data are not very specific. However, we must take it into account in the differential diagnosis of abdominal pain etiologies.

3.
Rev. Fac. Med. UNAM ; 66(5): 42-49, sep.-oct. 2023. graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1535216

RESUMO

Resumen El vólvulo de sigmoides ocurre como resultado de una torsión del eje mesentérico colónico, cuenta con una etiología multifactorial y controvertida, de fisiopatología no clara aún. Presenta un cuadro clínico de inicio inespecífico y posteriores signos y síntomas de oclusión intestinal; su diagnóstico se establece mediante tomografía computarizada, con una sensibilidad y especificidad mayor al 90%. El manejo dependerá de la condición clínica del paciente. Caso clínico: Hombre de 29 años con antecedente de síndrome de Asperger. Refirió que desde 7 días previos a su ingreso presentó dolor tipo cólico difuso, asociado a distensión abdominal e intolerancia a la vía oral. Acudió a valoración hospitalaria donde se realizóa tomografía computarizada con niveles hidroaéreos, torsión de arteria mesentérica inferior de aspecto de torbellino. Se realizó laparotomía exploradora a través de la cual se encontró sigmoides dilatado y volvulado, con perforación en la unión rectosigmoidea; se realizó sigmoidectomía con colorectoanastomosis. Al quinto día presentó datos de respuesta inflamatoria con abdomen agudo, por lo que ingresó a laparotomía exploradora donde se encontró dehiscencia de anastomosis; se realizó procedimiento de Hartmann. El paciente presentó choque séptico y falleció a las 24 horas del postquirúrgico. Discusión: La presentación de vólvulo sigmoides generalmente se presenta en personas mayores de 70 años, pocos casos se describen en personas jóvenes y están relacionados con enfermedad de dismotilidad intestinal. El paciente no contaba con factores predisponentes, el diagnóstico se estableció con imágenes características de la enfermedad, como la imagen en torbellino, se decidió manejo quirúrgico con la realización de resección con colorectoanastomosis. Conclusión: La oclusión intestinal por vólvulo sigmoides es una patología infrecuente en jóvenes y de clínica inespecífica. Ante un paciente que presente datos de oclusión intestinal deberá ser abordado de manera apropiada, sobre todo en pacientes en quienes hayan debutado con una clínica insidiosa y persistente de dolor abdominal secundario a oclusión intestinal, sean jóvenes con o sin factores de riesgo.


Abstract Sigmoid volvulus occurs due to a torsion of the colonic mesenteric axis, it has a multifactorial and controversial etiology, and its pathophysiology is not yet clear. Presenting a clinical picture of non-specific onset and later signs and symptoms of intestinal occlusion, its diagnosis is established with computed tomography with a sensitivity and specificity greater than 90%. Management will depend on the clinical condition of the patient. Clinical case: A 29-year-old man with a history of Asperger syndrome. He referred 7 days prior to admission with diffuse cramping pain, associated with abdominal distension and oral intolerance. He went to the hospital for evaluation where a computed tomography was performed with air-fluid levels, torsion of the inferior mesenteric artery with a whirlwind appearance. Exploratory laparotomy was performed, finding a dilated and volvulated sigmoid with perforation at the rectosigmoid junction. A sigmoidectomy with colorectal anastomosis was performed. On the fifth day, he presented data of inflammatory response with acute abdomen, entering exploratory laparotomy finding anastomosis dehiscence, Hartmann procedure was performed. The patient presented septic shock, died 24 hours after surgery. Discussion: The presentation of sigmoid volvulus generally occurs in people older than 70 years, few cases are described in young people and are related to intestinal dysmotility disease, the patient did not have predisposing factors, the diagnosis is established with characteristic images of the disease such as whirlwind image, surgical management is decided by performing resection with colorectal anastomosis. Conclusion: Intestinal occlusion due to sigmoid volvulus is an infrequent pathology in young people and with non-specific symptoms. When faced with a patient presenting evidence of intestinal occlusion, this should be appropriately addressed, especially in patients who have debuted with insidious and persistent symptoms of abdominal pain secondary to intestinal occlusion, whether they are young with or without risk factors.

4.
Trauma Case Rep ; 47: 100912, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37637455

RESUMO

This report presents the case of a 25-year-old male with an infected tibial diaphyseal nonunion caused by a bone transport procedure carried out to treat an open fracture the patient had sustained 10 years before referral to our hospital. After an initial radical debridement, a bone defect was created, which was subsequently obliterated by placement of an antibiotic-impregnated cement spacer and Stimulan beads and covered by an anterolateral thigh flap. As the patient refused to wear an external fixator and his osseous biology was not amenable to a Masquelet procedure, a decision was made to apply the Capanna technique as soon as the infection healed. The second debridement resulted in a 12-cm-long bone defect that was filled with a tibial allograft and a vascularized fibular graft. At six months, the patient had regained full knee function and was able to bear his full weight, without pain or the need of support equipment. At one year, the bone had healed completely, the infection had subsided and the patient was able to resume his everyday activities. Although the Capanna technique was initially developed to reinforce reconstructions at risk of fracture or nonunion as a result of chemotherapy, its use in post-traumatic cases has been shown to be successful in a selected group of patents. Our study demonstrated that increasing the stability of a reconstruction with an allograft can accelerate the time to heal, and that using a vascularized fibular graft can enhance incorporation of the whole construct. It can be concluded that the Capanna technique is a valid treatment option for managing infected segmental bone defects in selected patients.

5.
ACS Cent Sci ; 9(3): 393-404, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36968546

RESUMO

The emergence of a polybasic cleavage motif for the protease furin in SARS-CoV-2 spike has been established as a major factor for human viral transmission. The region N-terminal to that motif is extensively mutated in variants of concern (VOCs). Besides furin, spikes from these variants appear to rely on other proteases for maturation, including TMPRSS2. Glycans near the cleavage site have raised questions about proteolytic processing and the consequences of variant-borne mutations. Here, we identify that sialic acid-containing O-linked glycans on Thr678 of SARS-CoV-2 spike influence furin and TMPRSS2 cleavage and posit O-linked glycosylation as a likely driving force for the emergence of VOC mutations. We provide direct evidence that the glycosyltransferase GalNAc-T1 primes glycosylation at Thr678 in the living cell, an event that is suppressed by mutations in the VOCs Alpha, Delta, and Omicron. We found that the sole incorporation of N-acetylgalactosamine did not impact furin activity in synthetic O-glycopeptides, but the presence of sialic acid reduced the furin rate by up to 65%. Similarly, O-glycosylation with a sialylated trisaccharide had a negative impact on TMPRSS2 cleavage. With a chemistry-centered approach, we substantiate O-glycosylation as a major determinant of spike maturation and propose disruption of O-glycosylation as a substantial driving force for VOC evolution.

6.
Vet Res Commun ; 47(2): 615-629, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36229725

RESUMO

Severe Acute Respiratory Syndrome Coronavirus 2 is the causative agent of Coronavirus Disease 2019 in humans. Among domestic animals, cats are more susceptible to SARS-CoV-2 than dogs. The detection of anti-SARS-CoV-2 antibodies in seemingly healthy cats and/or infected cats which are in close contact with infected humans has been described. The presence of animals that tested positive by serology or molecular techniques could represent a potential transmission pathway of SARS-CoV-2 that can spill over into urban wildlife. This study analyses the seroprevalence variation of SARS-CoV-2 in stray cats from different waves of outbreaks in a geographical area where previous seroepidemiological information of SARS-CoV-2 was available and investigate if SARS-CoV-2-seropositive cats were exposed to other co-infections causing an immunosuppressive status and/or a chronic disease that could lead to a SARS-CoV-2 susceptibility. For this purpose, a total of 254 stray cats from Zaragoza (Spain) were included. This analysis was carried out by the enzyme-linked immunosorbent assay using the receptor binding domain of Spike antigen and confirmed by serum virus neutralization assay. The presence of co-infections including Toxoplasma gondii, Leishmania infantum, Dirofilaria immitis, feline calicivirus, feline herpesvirus type 1, feline leukemia virus and feline immunodeficiency virus, was evaluated using different serological methods. A seropositivity of 1.57% was observed for SARS-CoV-2 including the presence of neutralizing antibodies in three cats. None of the seropositive to SARS-CoV-2 cats were positive to feline coronavirus, however, four SARS-CoV-2-seropositive cats were also seropositive to other pathogens such as L. infantum, D. immitis and FIV (n = 1), L. infantum and D. immitis (n = 1) and L. infantum alone (n = 1).Considering other pathogens, a seroprevalence of 16.54% was detected for L. infantum, 30.31% for D. immitis, 13.78%, for T. gondii, 83.86% for feline calicivirus, 42.52% for feline herpesvirus type 1, 3.15% for FeLV and 7.87% for FIV.Our findings suggest that the epidemiological role of stray cats in SARS-CoV-2 transmission is scarce, and there is no increase in seropositivity during the different waves of COVID-19 outbreaks in this group of animals. Further epidemiological surveillances are necessary to determine the risk that other animals might possess even though stray cats do not seem to play a role in transmission.


Assuntos
COVID-19 , Doenças do Gato , Coinfecção , Dirofilaria immitis , Doenças do Cão , Vírus da Imunodeficiência Felina , Humanos , Gatos , Animais , Cães , Doenças do Gato/epidemiologia , SARS-CoV-2 , Coinfecção/epidemiologia , Coinfecção/veterinária , Espanha/epidemiologia , Estudos Soroepidemiológicos , Estudos Transversais , COVID-19/epidemiologia , COVID-19/veterinária , Vírus da Leucemia Felina , Surtos de Doenças , Doenças do Cão/epidemiologia
7.
Antibiotics (Basel) ; 11(11)2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36358194

RESUMO

Since the introduction of antibiotics in the 1930s, the form and philosophy of their use has changed considerably [...].

8.
Preprint em Inglês | bioRxiv | ID: ppbiorxiv-508093

RESUMO

The emergence of a polybasic cleavage motif for the protease furin in the SARS-CoV-2 spike protein has been established as a major factor for enhanced viral transmission in humans. The peptide region N-terminal to that motif is extensively mutated in major variants of concern including Alpha, Delta and Omicron. Besides furin, spike proteins from these variants appear to rely on other proteases for maturation, including TMPRSS2 that may share the same cleavage motif. Glycans found near the cleavage site have raised questions about proteolytic processing and the consequences of variant-borne mutations. Here, with a suite of chemical tools, we establish O-linked glycosylation as a major determinant of SARS-CoV-2 spike cleavage by the host proteases furin and TMPRSS2, and as a likely driving force for the emergence of common mutations in variants of concern. We provide direct evidence that the glycosyltransferase GalNAc-T1 primes glycosylation at Thr678 in the living cell, and this glycosylation event is suppressed by many, but not all variant mutations. A novel strategy for rapid bioorthogonal modification of Thr678-containing glycopeptides revealed that introduction of a negative charge completely abrogates furin activity. In a panel of synthetic glycopeptides containing elaborated O-glycans, we found that the sole incorporation of N-acetylgalactosamine did not substantially impact furin activity, but the presence of sialic acid in elaborated O-glycans reduced furin rate by up to 65%. Similarly, O-glycosylation with a sialylated trisaccharide had a negative impact on spike cleavage by TMPRSS2. With a chemistry-centered approach, we firmly establish O-glycosylation as a major determinant of spike maturation and propose that a disruption of O-GalNAc glycosylation is a substantial driving force for the evolution of variants of concern. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=89 SRC="FIGDIR/small/508093v3_ufig1.gif" ALT="Figure 1"> View larger version (26K): org.highwire.dtl.DTLVardef@71b54eorg.highwire.dtl.DTLVardef@1361b4aorg.highwire.dtl.DTLVardef@139bdd9org.highwire.dtl.DTLVardef@1df192b_HPS_FORMAT_FIGEXP M_FIG C_FIG

9.
Arq Neuropsiquiatr ; 80(6): 653-655, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35946716

RESUMO

Pavlov and Cajal were two influential scientists who developed their work in the late nineteenth and early twentieth centuries. Both won the Nobel Prize in Physiology or Medicine. The authors analyze the similarities between their life and work, delving into a single aspect: the Nobel prize obtained by both with only two years of difference: Pavlov in 1904 and Cajal in 1906, shared with Camilo Golgi. Both belonged to two declining empires when nationalism was still of some importance. The theories proposed by them more than 115 years ago are still valid in much of what they contributed in their respective disciplines.


Assuntos
Prêmio Nobel , História do Século XIX , História do Século XX , Humanos
10.
Nat Commun ; 13(1): 4324, 2022 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-35882872

RESUMO

Mucinases of human gut bacteria cleave peptide bonds in mucins strictly depending on the presence of neighboring O-glycans. The Akkermansia muciniphila AM0627 mucinase cleaves specifically in between contiguous (bis) O-glycans of defined truncated structures, suggesting that this enzyme may recognize clustered O-glycan patches. Here, we report the structure and molecular mechanism of AM0627 in complex with a glycopeptide containing a bis-T (Galß1-3GalNAcα1-O-Ser/Thr) O-glycan, revealing that AM0627 recognizes both the sugar moieties and the peptide sequence. AM0627 exhibits preference for bis-T over bis-Tn (GalNAcα1-O-Ser/Thr) O-glycopeptide substrates, with the first GalNAc residue being essential for cleavage. AM0627 follows a mechanism relying on a nucleophilic water molecule and a catalytic base Glu residue. Structural comparison among mucinases identifies a conserved Tyr engaged in sugar-π interactions in both AM0627 and the Bacteroides thetaiotaomicron BT4244 mucinase as responsible for the common activity of these two mucinases with bis-T/Tn substrates. Our work illustrates how mucinases through tremendous flexibility adapt to the diversity in distribution and patterns of O-glycans on mucins.


Assuntos
Glicoproteínas , Polissacarídeos , Carboidratos , Glicopeptídeos/química , Humanos , Intestinos , Mucinas/química , Polissacarídeo-Liases , Polissacarídeos/química , República da Coreia , Açúcares
11.
Arq. neuropsiquiatr ; 80(6): 653-655, June 2022.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1393974

RESUMO

ABSTRACT Pavlov and Cajal were two influential scientists who developed their work in the late nineteenth and early twentieth centuries. Both won the Nobel Prize in Physiology or Medicine. The authors analyze the similarities between their life and work, delving into a single aspect: the Nobel prize obtained by both with only two years of difference: Pavlov in 1904 and Cajal in 1906, shared with Camilo Golgi. Both belonged to two declining empires when nationalism was still of some importance. The theories proposed by them more than 115 years ago are still valid in much of what they contributed in their respective disciplines.


RESUMEN Pavlov y Cajal fueron dos científicos influyentes que desarrollaron su trabajo a finales del siglo XIX y principios del XX. Ambos ganaron el premio Nobel de Fisiología o Medicina. Los autores analizan las similitudes entre su vida y obra, profundizando en un solo aspecto: el premio Nobel obtenido por ambos con tan solo dos años de diferencia: Pavlov en 1904 y Cajal en 1906, compartido con Camilo Golgi. Ambos pertenecían a dos imperios en decadencia, en un momento en que el nacionalismo todavía tenía cierta importancia. Las teorías propuestas por ellos, hace más de 115 años, siguen vigentes en lo fundamental de lo que aportaron en sus respectivas disciplinas.

12.
An Pediatr (Engl Ed) ; 96(5): 385-393, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35550788

RESUMO

INTRODUCTION: Data surrounding palliative sedation in pediatric patients is scarce. Our objective is to assess the utility of creating a quality standard for pediatric palliative sedation. MATERIAL AND METHODS: A non-systematic review of the literature was used to find recommendations for pediatric palliative sedation, after which a definition was established based on three items: (1) indication, (2) consent, and (3) application. Afterwards, a retrospective analysis of palliative sedations applied by our unit over 5 years was performed. RESULTS: Out of 163 patients, palliative sedation was applied in 20, in 17 of them by our unit (14/20 males; median: 11.9 years). Twelve patients had oncological diseases, seven had neurological conditions, and one had a polymalformative syndrome. Nine patients had more than one symptom at the time of PS initiation with pain (11/17) and dyspnoea (10/17) being the most frequent. As for the definition, only three patients achieved a global completion, with the registration of the consent, specification of refractoriness and the establishment of an adequate initial sedative dose being the areas with more possible improvement. CONCLUSIONS: The application of the definition allowed us to analyze and find areas of improvement for our clinical practice of palliative sedation in pediatric patients.


Assuntos
Hipnóticos e Sedativos , Cuidados Paliativos , Criança , Unidades Hospitalares , Humanos , Hipnóticos e Sedativos/uso terapêutico , Masculino , Estudos Retrospectivos
13.
Nat Commun ; 13(1): 2398, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35504880

RESUMO

C1GalT1 is an essential inverting glycosyltransferase responsible for synthesizing the core 1 structure, a common precursor for mucin-type O-glycans found in many glycoproteins. To date, the structure of C1GalT1 and the details of substrate recognition and catalysis remain unknown. Through biophysical and cellular studies, including X-ray crystallography of C1GalT1 complexed to a glycopeptide, we report that C1GalT1 is an obligate GT-A fold dimer that follows a SN2 mechanism. The binding of the glycopeptides to the enzyme is mainly driven by the GalNAc moiety while the peptide sequence provides optimal kinetic and binding parameters. Interestingly, to achieve glycosylation, C1GalT1 recognizes a high-energy conformation of the α-GalNAc-Thr linkage, negligibly populated in solution. By imposing this 3D-arrangement on that fragment, characteristic of α-GalNAc-Ser peptides, C1GalT1 ensures broad glycosylation of both acceptor substrates. These findings illustrate a structural and mechanistic blueprint to explain glycosylation of multiple acceptor substrates, extending the repertoire of mechanisms adopted by glycosyltransferases.


Assuntos
Glicopeptídeos , Mucinas , Sequência de Aminoácidos , Cristalografia por Raios X , Glicopeptídeos/química , Glicosilação , Mucinas/metabolismo
14.
An. pediatr. (2003. Ed. impr.) ; 96(5): 385-393, mayo 2022. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-206049

RESUMO

Introducción:Existen pocos datos referentes a la práctica de sedación paliativa en población pediátrica. El objetivo de este estudio es crear una definición estandarizada de sedación paliativa para población pediátrica y aplicarlo en una Unidad de Cuidados Paliativos Pediátricos.Material y métodos:Se realizó una revisión no sistemática de la literatura en búsqueda de la evidencia y recomendaciones existentes para la práctica de sedación en población pediátrica, tras lo cual se creó una definición de sedación paliativa basada en tres ítems: 1. Indicación 2. Consentimiento 3. Aplicación. Posteriormente se realizó una revisión retrospectiva de registros clínicos para analizar la práctica de sedación paliativa atendidos por la Unidad de Atención Integral Paliativa Pediátrica de Madrid (UAIPPM) en un periodo de cinco años (enero 2013-diciembre 2017).Resultados:De 163 pacientes analizados, la sedación se aplicó en 20, 17 pacientes de la propia Unidad (70% varones; mediana de edad: 11,9 años); 12 pacientes padecían cáncer, siete enfermedades neurológicas y uno un síndrome polimalformativo; 52,9% pacientes sufrían más de un síntoma en el momento de indicar la sedación paliativa, siendo el dolor (64,7%) y la disnea (58,8%) los más frecuentes. En cuanto a la definición, sólo tres pacientes consiguieron una cumplimentación global de la misma, siendo el registro del consentimiento informado el área con mayor potencial de mejora.Conclusiones:La evaluación basada en una definición estandarizada permitió definir la práctica de sedación paliativa en nuestra Unidad y encontrar áreas potenciales de mejora. (AU)


Introduction:Data surrounding palliative sedation in pediatric patients is scarce. Our objective is to assess the utility of creating a quality standard for pediatric palliative sedation.Material and methods:A non-systematic review of the literature was used to find recommendations for pediatric palliative sedation, after which a definition was established based on three items: (1) indication, (2) consent, and (3) application. Afterwards, a retrospective analysis of palliative sedations applied by our unit over 5 years was performed.Results:Out of 163 patients, palliative sedation was applied in 20, in 17 of them by our unit (14/20 males; median: 11.9 years). Twelve patients had oncological diseases, seven had neurological conditions, and one had a polymalformative syndrome. Nine patients had more than one symptom at the time of PS initiation with pain (11/17) and dyspnoea (10/17) being the most frequent. As for the definition, only three patients achieved a global completion, with the registration of the consent, specification of refractoriness and the establishment of an adequate initial sedative dose being the areas with more possible improvement.Conclusions:The application of the definition allowed us to analyze and find areas of improvement for our clinical practice of palliative sedation in pediatric patients. (AU)


Assuntos
Humanos , Criança , Adolescente , Cuidados Paliativos , Pediatria , Serviços de Saúde da Criança , 28599 , Estudos Retrospectivos
15.
PLoS Biol ; 20(4): e3001601, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35417450

RESUMO

Coat complexes coordinate cargo recognition through cargo adaptors with biogenesis of transport carriers during integral membrane protein trafficking. Here, we combine biochemical, structural, and cellular analyses to establish the mechanistic basis through which SNX27-Retromer, a major endosomal cargo adaptor, couples to the membrane remodeling endosomal SNX-BAR sorting complex for promoting exit 1 (ESCPE-1). In showing that the SNX27 FERM (4.1/ezrin/radixin/moesin) domain directly binds acidic-Asp-Leu-Phe (aDLF) motifs in the SNX1/SNX2 subunits of ESCPE-1, we propose a handover model where SNX27-Retromer captured cargo proteins are transferred into ESCPE-1 transport carriers to promote endosome-to-plasma membrane recycling. By revealing that assembly of the SNX27:Retromer:ESCPE-1 coat evolved in a stepwise manner during early metazoan evolution, likely reflecting the increasing complexity of endosome-to-plasma membrane recycling from the ancestral opisthokont to modern animals, we provide further evidence of the functional diversification of yeast pentameric Retromer in the recycling of hundreds of integral membrane proteins in metazoans.


Assuntos
Endossomos , Nexinas de Classificação , Animais , Membrana Celular/metabolismo , Endossomos/metabolismo , Transporte Proteico , Nexinas de Classificação/metabolismo
16.
Nucleic Acids Res ; 50(6): e31, 2022 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-34904657

RESUMO

DNA processing enzymes, such as DNA polymerases and endonucleases, have found many applications in biotechnology, molecular diagnostics, and synthetic biology, among others. The development of enzymes with controllable activity, such as hot-start or light-activatable versions, has boosted their applications and improved the sensitivity and specificity of the existing ones. However, current approaches to produce controllable enzymes are experimentally demanding to develop and case-specific. Here, we introduce a simple and general method to design light-start DNA processing enzymes. In order to prove its versatility, we applied our method to three DNA polymerases commonly used in biotechnology, including the Phi29 (mesophilic), Taq, and Pfu polymerases, and one restriction enzyme. Light-start enzymes showed suppressed polymerase, exonuclease, and endonuclease activity until they were re-activated by an UV pulse. Finally, we applied our enzymes to common molecular biology assays and showed comparable performance to commercial hot-start enzymes.


Assuntos
Biotecnologia/métodos , DNA Polimerase Dirigida por DNA , DNA , DNA/genética , DNA Polimerase Dirigida por DNA/genética , Endonucleases
17.
Transbound Emerg Dis ; 69(3): 1056-1064, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-33686768

RESUMO

A new coronavirus known as SARS-CoV-2 emerged in Wuhan in 2019 and spread rapidly to the rest of the world causing the pandemic disease named coronavirus disease of 2019 (COVID-19). Little information is known about the impact this virus can cause upon domestic and stray animals. The potential impact of SARS-CoV-2 has become of great interest in cats due to transmission among domestic cats and the severe phenotypes described recently in a domestic cat. In this context, there is a public health warning that needs to be investigated in relation with the epidemiological role of this virus in stray cats. Consequently, in order to know the impact of the possible transmission chain, blood samples were obtained from 114 stray cats in the city of Zaragoza (Spain) and tested for SARS-CoV-2 and other selected pathogens susceptible to immunosuppression including Toxoplasma gondii, Leishmania infantum, feline leukaemia virus (FeLV) and feline immunodeficiency virus (FIV) from January to October 2020. Four cats (3.51%), based on enzyme-linked immunosorbent assay (ELISA) using the receptor binding domain (RBD) of Spike antigen, were seroreactive to SARS-CoV-2. T. gondii, L. infantum, FeLV and FIV seroprevalence was 12.28%, 16.67%, 4.39% and 19.30%, respectively. Among seropositive cats to SARS-CoV-2, three cats were also seropositive to other pathogens including antibodies detected against T. gondii and FIV (n = 1); T. gondii (n = 1); and FIV and L. infantum (n = 1). The subjects giving positive for SARS-CoV-2 were captured in urban areas of the city in different months: January 2020 (2/4), February 2020 (1/4) and July 2020 (1/4). This study revealed, for the first time, the exposure of stray cats to SARS-CoV-2 in Spain and the existence of concomitant infections with other pathogens including T. gondii, L. infantum and FIV, suggesting that immunosuppressed animals might be especially susceptible to SARS-CoV-2 infection.


Assuntos
COVID-19 , Doenças do Gato , Coinfecção , Vírus da Imunodeficiência Felina , Animais , Animais Selvagens , COVID-19/epidemiologia , COVID-19/veterinária , Doenças do Gato/epidemiologia , Gatos , Coinfecção/epidemiologia , Coinfecção/veterinária , Humanos , Vírus da Leucemia Felina , SARS-CoV-2 , Estudos Soroepidemiológicos , Espanha/epidemiologia
19.
Antioxidants (Basel) ; 10(9)2021 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-34573078

RESUMO

Lignin biodegradation has been extensively studied in white-rot fungi, which largely belong to order Polyporales. Among the enzymes that wood-rotting polypores secrete, lignin peroxidases (LiPs) have been labeled as the most efficient. Here, we characterize a similar enzyme (ApeLiP) from a fungus of the order Agaricales (with ~13,000 described species), the soil-inhabiting mushroom Agrocybe pediades. X-ray crystallography revealed that ApeLiP is structurally related to Polyporales LiPs, with a conserved heme-pocket and a solvent-exposed tryptophan. Its biochemical characterization shows that ApeLiP can oxidize both phenolic and non-phenolic lignin model-compounds, as well as different dyes. Moreover, using stopped-flow rapid spectrophotometry and 2D-NMR, we demonstrate that ApeLiP can also act on real lignin. Characterization of a variant lacking the above tryptophan residue shows that this is the oxidation site for lignin and other high redox-potential substrates, and also plays a role in phenolic substrate oxidation. The reduction potentials of the catalytic-cycle intermediates were estimated by stopped-flow in equilibrium reactions, showing similar activation by H2O2, but a lower potential for the rate-limiting step (compound-II reduction) compared to other LiPs. Unexpectedly, ApeLiP was stable from acidic to basic pH, a relevant feature for application considering its different optima for oxidation of phenolic and nonphenolic compounds.

20.
Antibiotics (Basel) ; 10(8)2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34439007

RESUMO

The aim of the study was to investigate the intramuscular pharmacokinetics of enrofloxacin in black vultures (Coragyps atratus). The pharmacokinetics of a single intramuscular dose (10 mg/kg) of enrofloxacin was studied in six vultures. Plasma concentrations of enrofloxacin and its active metabolite, ciprofloxacin, were determined by high-performance liquid chromatography (HPLCuv). Pharmacokinetic parameters were estimated using non-compartmental and compartmental analysis. After intramuscular administration, enrofloxacin showed a rapid and complete absorption, reaching a Cmax value of 3.26 ± 0.23 µg/mL at 1.75 ± 0.53 h. A long terminal half-life of 19.58 h has been observed. Using previously published MIC values to perform a PK/PD analysis, cumulative fraction responses obtained after Monte Carlo simulation for AUC/MIC > 30, 50 and 125 were 72.93%, 72.34% and 30.86% for E. coli and 89.29%, 88.89% and 58.57% for Mycoplasma synoviae, respectively. Cumulative fraction responses obtained for Cmax/MIC index were 33.93% and 40.18% for E. coli and M. synoviae, respectively. The intramuscular administration of 10 mg/kg could be appropriate to treat infectious diseases caused by gram-positive bacteria with MIC value lower than 1 µg/mL; however, although enrofloxacin showed a slow elimination in black vultures, plasma concentrations were insufficient to reach the gram-negative stablished breakpoints.

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