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1.
Am J Physiol Cell Physiol ; 326(4): C1178-C1192, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38406825

RESUMO

K+ channel Kir7.1 expressed at the apical membrane of the retinal pigment epithelium (RPE) plays an essential role in retinal function. An isoleucine-to-threonine mutation at position 120 of the protein is responsible for blindness-causing vitreo-retinal dystrophy. We have studied the molecular mechanism of action of Kir7.1-I120T in vitro by heterologous expression and in vivo in CRISPR-generated knockin mice. Full-size Kir7.1-I120T reaches the plasma membrane but lacks any activity. Analysis of Kir7.1 and the I120T mutant in mixed transfection experiments, and that of tandem tetrameric constructs made by combining wild type (WT) and mutant protomers, leads us to conclude that they do not form heterotetramers in vitro. Homozygous I120T/I120T mice show cleft palate and tracheomalacia and do not survive beyond P0, whereas heterozygous WT/I120T develop normally. Membrane conductance of RPE cells isolated from WT/WT and heterozygous WT/I120T mice is dominated by Kir7.1 current. Using Rb+ as a charge carrier, we demonstrate that the Kir7.1 current of WT/I120T RPE cells corresponds to approximately 50% of that in cells from WT/WT animals, in direct proportion to WT gene dosage. This suggests a lack of compensatory effects or interference from the mutated allele product, an interpretation consistent with results obtained using WT/- hemizygous mouse. Electroretinography and behavioral tests also show normal vision in WT/I120T animals. The hypomorphic ion channel phenotype of heterozygous Kir7.1-I120T mutants is therefore compatible with normal development and retinal function. The lack of detrimental effect of this degree of functional deficit might explain the recessive nature of Kir7.1 mutations causing human eye disease.NEW & NOTEWORTHY Human retinal pigment epithelium K+ channel Kir7.1 is affected by generally recessive mutations leading to blindness. We investigate one such mutation, isoleucine-to-threonine at position 120, both in vitro and in vivo in knockin mice. The mutated channel is inactive and in heterozygosis gives a hypomorphic phenotype with normal retinal function. Mutant channels do not interfere with wild-type Kir7.1 channels which are expressed concomitantly without hindrance, providing an explanation for the recessive nature of the disease.


Assuntos
Isoleucina , Retina , Camundongos , Humanos , Animais , Isoleucina/metabolismo , Retina/metabolismo , Cegueira/metabolismo , Mutação/genética , Treonina/metabolismo
2.
Fetal Diagn Ther ; 2023 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-38008087

RESUMO

BACKGROUND: Limited information exists in the prenatal literature regarding the neuroimaging features of fetal hemimegalencephaly. SUMMARY: This report describes ultrasound and magnetic resonance imaging (MRI) findings in a second-trimester fetus with an isolated, severe form of hemimegalencephaly. The most prominent imaging findings included unilateral enlarged cerebral hemisphere and ipsilateral ventriculomegaly causing cerebral asymmetry, midline shift and macrocephaly. Abnormal cortical development imaging signs were also evident. A literature review encompassing 23 reports describing 36 cases, including ours, is presented. KEY MESSAGES: Characteristic ultrasound findings for the diagnosis of hemimegalencephaly are not always apparent prenatally. Asymmetric ventriculomegaly emerges as the most common but nonspecific presenting feature during routine second- or third-trimester ultrasound scans. Subsequent high-resolution prenatal neurosonography and fetal MRI facilitate definitive prenatal diagnosis, showcasting associated features primarily related to cortical migration, differentiation, and maturation. Postnatally, the prognosis is poor due to intractable seizures, hemiplegia and progressive neurodevelopmental delay.

3.
J Surg Case Rep ; 2023(7): rjad407, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37489161

RESUMO

The annular pancreas (AP) is an uncommon congenital anomaly, characterised by a circumferential envelope in the second portion of the duodenum. In recent years, some genetic component has been found in the etiology. A newborn full-term male, weighing at 1910 g at birth, had a history of intrauterine growth restriction and diagnosis of tetralogy of Fallot, Down syndrome and congenital hypothyroidism. Duodenal membrane is suspected after persistent postprandial vomiting and abdominal distension; his abdomen was distended, hyperresonant and soft. The gastroduodenal series showed data compatible with a duodenal membrane so exploratory laparotomy was performed, finding the pancreas completely wrapping the second portion of the duodenum, so a diamond-shaped-duodenoduodenostomy anastomosis was performed. The AP should be considered, especially in male neonates with postprandial vomiting, abdominal distension, who show some other congenital anomaly, and in the abdominal X-ray, the sign of the double bubble is observed.

4.
Fetal Diagn Ther ; 50(3): 165-174, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37015213

RESUMO

INTRODUCTION: The detection of absent septi pellucidi (ASP) during obstetric ultrasound is a rare event. However, the clinical implications of this finding are significant. ASP can be associated with severe central nervous system anomalies such as holoprosencephaly, agenesis/dysgenesis of the corpus callosum, schizencephaly, severe ventriculomegaly, and open neural tube defects. In such cases, the prognosis is poor. When no such anomalies are identified, isolated ASP usually carries a good prognosis. However, some fetuses thought to have isolated ASP actually have septo-optic dysplasia (SOD), which is associated with optic nerve hypoplasia, hypothalamic-pituitary dysfunction, and developmental delay. CASE PRESENTATION: A case in which fetal 3.0 Tesla magnetic resonance imaging (MRI) was considered crucial to definitively diagnose isolated ASP is presented. A review of the literature was conducted and analyzed to determine the role of MRI in the evaluation of fetuses with ASP, with special consideration on the differential diagnosis between isolated ASP and SOD. CONCLUSION: Differentiating isolated ASP from SOD is imperative for adequate prenatal counseling. Unfortunately, making a prenatal diagnosis of SOD requires visualization and evaluation of the fetal optic nerves, chiasm, and pituitary gland, which is very demanding and not always possible using ultrasound. Fetal MRI has the potential of obtaining high-quality images of the fetal brain, and therefore this technique can be used for establishing the differential diagnosis in utero.


Assuntos
Malformações do Sistema Nervoso , Displasia Septo-Óptica , Gravidez , Feminino , Humanos , Displasia Septo-Óptica/diagnóstico por imagem , Displasia Septo-Óptica/complicações , Diagnóstico Pré-Natal , Feto/patologia , Imageamento por Ressonância Magnética , Agenesia do Corpo Caloso/complicações
5.
PLoS Pathog ; 19(3): e1011188, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36917600

RESUMO

Sea louse ectoparasitosis is a major threat to fish aquaculture. Avermectins such as ivermectin and emamectin have been effectively used against sea louse infestation, but the emergence of resistance has limited their use. A better understanding of the molecular targets of avermectins is essential to the development of novel treatment strategies or new, more effective drugs. Avermectins are known to act by inhibiting neurotransmission through allosteric activation of glutamate-gated chloride channels (GluCls). We have investigated the GluCl subunit present in Caligus rogercresseyi, a sea louse affecting aquaculture in the Southern hemisphere. We identify four new subunits, CrGluCl-B to CrGluCl-E, and characterise them functionally. CrGluCl-A (previously reported as CrGluClα), CrGluCl-B and CrGluCl-C all function as glutamate channel receptors with different sensitivities to the agonist, but in contrast to subunit -A and -C, CrGluCl-B is not activated by ivermectin but is rather antagonised by the drug. CrGluCl-D channel appears active in the absence of any stimulation by glutamate or ivermectin and CrGluCl-E does not exhibit any activity. Notably, the expression of CrGluCl-B with either -A or -C subunits gives rise to receptors unresponsive to ivermectin and showing altered response to glutamate, suggesting that coexpression has led to the preferential formation of heteromers to which the presence of CrGluCl-B confers the property of ivermectin-activation refractoriness. Furthermore, there was evidence for heteromer formation with novel properties only when coexpressing pairs E/C and D/B CrGluCl subtypes. Site-directed mutagenesis shows that three transmembrane domain residues contribute to the lack of activation by ivermectin, most crucially Gln 15' in M2, with mutation Q15'T (the residue present in ivermectin-activated subunits A and C) conferring ivermectin activation to CrGluCl-B. The differential response to avermectin of these Caligus rogercresseyi GluClsubunits, which are highly conserved in the Northern hemisphere sea louse Lepeophtheirus salmonis, could have an influence on the response of these parasites to treatment with macrocyclic lactones. They could serve as molecular markers to assess susceptibility to existing treatments and might be useful molecular targets in the search for novel antiparasitic drugs.


Assuntos
Copépodes , Parasitos , Ftirápteros , Animais , Ivermectina/farmacologia , Ivermectina/metabolismo , Ftirápteros/metabolismo , Parasitos/metabolismo , Canais de Cloreto/genética , Canais de Cloreto/metabolismo , Ácido Glutâmico/farmacologia
6.
J Clin Ultrasound ; 51(2): 346-361, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36785498

RESUMO

Cleft lip, with or without cleft palate, is the most common congenital craniofacial anomaly and the second most common birth defect worldwide. Micrognathia is a rare facial malformation characterized by small, underdeveloped mandible and frequently associated with retrognathia. Second- and third-trimester prenatal ultrasound is the standard modality for screening and identification of fetal orofacial abnormalities, with a detection rate in the low-risk population ranging from 0% to 73% for all types of cleft. The prenatal ultrasonography detection can also be performed during the first trimester of pregnancy. Given the potential limitations of obstetric ultrasound for examining the fetal face, such as suboptimal fetal position, shadowing from the surrounding bones, reduce amniotic fluid around the face, interposition of fetal limbs, umbilical cord and placenta, and maternal habitus/abdominal scars, the use of adjunct imaging modalities can enhance prenatal diagnosis of craniofacial anomalies in at-risk pregnancies. Fetal magnetic resonance imaging (MRI) is a potentially useful second-line investigation for the prenatal diagnosis of orofacial malformations with a pooled sensitivity of 97%. In this review, we discuss the role of ultrasound and fetal MRI in the prenatal assessment of abnormalities of the upper lip, palate, and mandible.


Assuntos
Fenda Labial , Fissura Palatina , Feminino , Gravidez , Humanos , Fenda Labial/diagnóstico por imagem , Fissura Palatina/diagnóstico por imagem , Diagnóstico Pré-Natal/métodos , Ultrassonografia Pré-Natal/métodos , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Mandíbula/diagnóstico por imagem
7.
Prenat Diagn ; 42(13): 1667-1673, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36321562

RESUMO

OBJECTIVE: To compare specific fetal cranial and cerebral findings indicative of prenatal intracranial hypotension (PICH) syndrome between open and closed cephaloceles. METHODS: Two groups of fetuses with cephalocele who underwent magnetic resonance imaging scan were selected based on the defect coverage: covered ("closed cephalocele" group, n = 4) and uncovered by skin ("open cephalocele" group, n = 8). The presence of signs associated with PICH syndrome was evaluated and findings compared between groups. RESULTS: Cases from the open cephalocele group showed statistically significant differences in comparison with the closed cephalocele group regarding reduction of the interpeduncular angle (p = 0.006), reduced amount of cerebrospinal fluid in the subarachnoid space (p = 0.01), collapsed/severely reduced fourth ventricle (p = 0.03), cephalocele content (p = 0.03), and identification of a vector traction (p = 0.03). There were no differences in the presence of cerebellar tonsillar descent, obstructive ventriculomegaly, and presence of the lemon sign. In comparison with gestational age-matched controls, only the biparietal diameter but not the head circumference was significantly smaller in both the open and closed cephalocele groups (p < 0.05). CONCLUSION: Congenital cephaloceles present distinct imaging behavior depending on the defect coverage. Therefore, the classification of cephalocele should include, in addition to location and content, the presence or absence of skin fully covering the defect.


Assuntos
Hidrocefalia , Hipotensão Intracraniana , Gravidez , Feminino , Humanos , Encefalocele/diagnóstico por imagem , Hipotensão Intracraniana/complicações , Hipotensão Intracraniana/diagnóstico por imagem , Diagnóstico Pré-Natal , Hidrocefalia/complicações , Síndrome
8.
J Med Chem ; 65(22): 15014-15027, 2022 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-36378530

RESUMO

Chemical structures of selective blockers of TASK channels contain aromatic groups and amide bonds. Using this rationale, we designed and synthesized a series of compounds based on 3-benzamidobenzoic acid. These compounds block TASK-1 channels by binding to the central cavity. The most active compound is 3-benzoylamino-N-(2-ethyl-phenyl)-benzamide or F3, blocking TASK-1 with an IC50 of 148 nM, showing a reduced inhibition of TASK-3 channels and not a significant effect on different K+ channels. We identified putative F3-binding sites in the TASK-1 channel by molecular modeling studies. Mutation of seven residues to A (I118A, L122A, F125A, Q126A, L232A, I235A, and L239A) markedly decreased the F3-induced inhibition of TASK-1 channels, consistent with the molecular modeling predictions. F3 blocks cell proliferation and viability in the MCF-7 cancer cell line but not in TASK-1 knockdown MCF-7 cells, indicating that it is acting in TASK-1 channels. These results indicated that TASK-1 is necessary to drive proliferation in the MCF-7 cancer cell line.


Assuntos
Neoplasias , Humanos , Relação Estrutura-Atividade , Sítios de Ligação , Proliferação de Células , Modelos Moleculares , Células MCF-7
9.
Can J Surg ; 65(5): E573-E579, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36302131

RESUMO

BACKGROUND: During kidney procurement, after ice removal, kidneys located in the retroperitoneum are at risk for rewarming owing to the time taken to retrieve other abdominal and thoracic organs, which may lead to poorer outcomes. The purpose of this study was to evaluate the impact of prolonged kidney procurement time (PKP) on outcomes of kidney transplantation performed at the Queen Elizabeth II Health Sciences Centre, Halifax, Nova Scotia, Canada. METHODS: We retrospectively reviewed the cases of all adult (age ≥ 18 yr) patients who underwent kidney transplantation at the Queen Elizabeth II Health Sciences Centre between Jan. 1, 2010, and Dec. 31, 2015. We included all patients who received kidney transplants from deceased donors with a minimum follow-up period of 3 years. We defined PKP as more than 65 minutes from aortic cross-clamp to final organ extraction, and standard procurement time (SP) as 65 minutes or less. RESULTS: Among the 455 transplantation procedures performed during the study period, we reviewed the cases of 145 patients who received kidneys from Nova Scotian donors and were followed in Nova Scotia. No statistically significant differences were seen in outcomes between kidney-only (n = 46) and multiorgan (n = 99) procurement, although more organs from kidney-only donors than multiorgan donors had a Kidney Donor Profile Index score greater than 50% (32 [69.6%] v. 48 [48.5%], p < 0.01). Compared to the SP group (n = 115), the PKP group (n = 30) had a higher rate of 30-day graft loss (6.7% v. 0.0%, p < 0.01), a higher incidence of de novo formation of donor-specific antibodies (3 [10.0%] v. 1 [0.9%], p < 0.01) and a lower 5-year graft survival rate (90.0% v. 97.4%, p = 0.03). Left kidneys remained 11 minutes longer on the donor than right kidneys when multiorgan procurement was performed (p < 0.01), and their 5-year survival rate was significantly lower than that of right kidneys (p = 0.03). CONCLUSION: Procurement times longer than 65 minutes may be associated with poorer outcomes after kidney transplantation. Measures to reduce kidney exposure to rewarming during procurement may improve long-term outcomes.


Assuntos
Transplante de Rim , Obtenção de Tecidos e Órgãos , Adulto , Humanos , Sobrevivência de Enxerto , Rim/cirurgia , Transplante de Rim/métodos , Nova Escócia , Estudos Retrospectivos , Doadores de Tecidos
10.
Cir Esp (Engl Ed) ; 100(10): 629-634, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36109114

RESUMO

BACKGROUND: Penetrating neck injuries represent 5-10% of all traumatic injuries, these bring with them a high rate of morbidity and mortality due to vital structures that could be injured in this area. The aim of this study was to determine the epidemiological and clinical characteristics of penetrating neck injuries. METHODS: This was a retrospective, unicentric and descriptive study that included all patients who underwent neck exploration surgery. RESULTS: A total of 70 neck exploration cases were reviewed, 34 (49%) didn't had any injury. Thirty (43%) had at least one hard sign, 42 (60%) patients showed at least one soft sign. Statistical analysis showed only surgical time (252±199.5 vs. 155±76.4; p=0.020) and transfusions (1.87±3 vs. 0.4±0.856; p=0.013) were statistically significant. We report a mortality of 2 (3%) patients. CONCLUSIONS: Our prevalence of neck surgical exploration without vascular injury was slightly higher (49% vs. 40%) than literature. We highlight the importance of not performing neck explorations in all patients who present a penetrating injury. We did not obtain differences between groups for hard signs and soft signs. We were not able to identify whether or not there would be an injury based on clinical characteristics. Imaging studies should be performed to avoid unnecessary neck explorations; however, depending on the clinical scenario some surgery cannot be avoided.


Assuntos
Lesões do Pescoço , Ferimentos Penetrantes , Humanos , Pescoço , Lesões do Pescoço/diagnóstico , Lesões do Pescoço/epidemiologia , Lesões do Pescoço/cirurgia , Estudos Retrospectivos , Centros de Traumatologia , Ferimentos Penetrantes/diagnóstico , Ferimentos Penetrantes/epidemiologia , Ferimentos Penetrantes/cirurgia
11.
Food Microbiol ; 107: 104058, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35953169

RESUMO

Efforts have been focusing on the way to overcome the impact of heating on food quality while achieving the desired shelf life. In this sense, the thermosensitization of E. coli using the natural antimicrobials vanillin (V; 0.8 and 1.0 g/L) or/and emulsified citral (C; 0.012 and 0.025 g/L) was assessed at 58 and 60 °C in blended carrot-orange juice (pH 4.0; 9.0°Brix). All combined treatments exceeded the inactivation achieved by the single thermal treatments in half the time. The inactivation of the binary treatments (V or C + heating) at 58 °C was 3.84-0.62 log-cycles more effective than the control, particularly with vanillin. Ternary treatments (V + C + heating) at 58 °C increased the microbial reduction approximately 30%; however, at 60 °C no further inactivation was observed, suggesting the thermal effect prevailed. This was verified by the higher b Weibullian parameter and the narrower frequency distributions. The selected treatments 1.0 V + 0.012C at 58 and 60 °C were challenged against the pathogenic E. coli O157:H7 and found to be effective. Additionally, the microbiota of the juice was maintained at acceptable levels during storage (4 °C). In conclusion, there was an increase in the heat sensitivity of E. coli due to the natural antimicrobials, particularly vanillin at 58 °C. Therefore, reducing the intensity of the thermal processing will lead to clean label, high-quality juices, while addressing food safety requirements.


Assuntos
Citrus sinensis , Daucus carota , Escherichia coli O157 , Monoterpenos Acíclicos , Benzaldeídos , Bebidas , Contagem de Colônia Microbiana , Daucus carota/química , Escherichia coli O157/fisiologia , Microbiologia de Alimentos , Temperatura Alta
12.
J Matern Fetal Neonatal Med ; 35(14): 2751-2758, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32723018

RESUMO

OBJECTIVE: To describe the main prenatal sonographic and magnetic resonance imaging (MRI) features leading to the diagnosis of Posterior fossa malformations, Hemangiomas of the face, Arterial anomalies, Coarctation of the aorta and cardiac defects, and Eye abnormalities (PHACE) syndrome. The literature was also reviewed in order to determine the main neuroimaging features of fetuses with this condition. RESULTS: The index case was referred at 24 weeks' gestation with the probable diagnosis of Dandy-Walker malformation. Prenatal sonographic examination revealed hypoplasia of the left cerebellar hemisphere, hypoplasia of the cerebellar vermis, and enlarged cisterna magna (the "tilted telephone receiver sign"). Fetal MRI at 30 weeks confirmed the findings and also revealed an ipsilateral retrocerebellar cyst communicating with the asymmetrical dilated fourth ventricle, upward displacement of the left cerebellar hemisphere, and elevation of the ipsilateral tentorium. Postnatally, a large left facial segmental hemangioma as well as ipsilateral vascular intracranial malformations were identified, confirming the diagnosis of PHACE syndrome. A review of the literature revealed 11 reports describing 22 fetuses with prenatal imaging studies, including ours, confirming the high prevalence of specific posterior fossa abnormalities associated with PHACE syndrome. CONCLUSION: Our case and those reported in the literature support the observation that PHACE syndrome presents with characteristic features affecting the posterior fossa, which can be identified through prenatal sonography and fetal MRI.


Assuntos
Coartação Aórtica , Anormalidades do Olho , Hemangioma , Síndromes Neurocutâneas , Coartação Aórtica/diagnóstico por imagem , Anormalidades do Olho/complicações , Anormalidades do Olho/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Síndromes Neurocutâneas/complicações , Síndromes Neurocutâneas/diagnóstico por imagem , Neuroimagem/métodos , Gravidez
13.
J Matern Fetal Neonatal Med ; 35(25): 6981-6987, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34074204

RESUMO

OBJECTIVE: To study the prevalence of abnormalities of the septi pellucidi (SP) in a cohort of fetuses with open spinal dysraphism (OSD) and to determine whether this condition is secondary to obstructive ventriculomegaly and, therefore, part of the natural history of prenatal intracranial hypotension (PICH) syndrome. METHODS: Magnetic resonance imaging (MRI) studies from fetuses with OSD were analyzed. The SP were assessed using axial and coronal T2-weighted images of the fetal brain and classified as intact, partially absent, or completely absent. Additionally, the correlation between the presence or absence of the SP and the size of the lateral ventricles, degree of cerebellar tonsillar herniation, collapse of the fourth ventricle, and interpeduncular angle was investigated. RESULTS: A total of 32 fetuses with OSD were studied. Mean gestational age at the time of the fetal MRI was 25.5 ± 3.9 weeks (range, 19-35) and mean ventricular size was 16.2 ± 4.2 mm (range, 8-26). Twenty-three (71.9%) fetuses had cerebellar tonsillar herniation. The IPA was completely collapsed in 23 cases (71.9%), reduced in seven (21.9%), and unreadable in two (6.3%). Twenty (62.5%) fetuses presented with intact SP, 10 (31.3%) with partially absent SP (incomplete fenestration), and two (6.3%) with completely absent SP (complete fenestration). Fenestration of the SP correlated significantly with the degree of ventriculomegaly (Pearson's correlation coefficient =0.459; p = .01). However, there was no correlation with the IPA, collapse of the fourth ventricle, and cerebellar tonsillar herniation. CONCLUSIONS: More than one-third of the fetuses with OSD had fenestration of the SP. The most probable etiology is increased intraventricular pressure leading to local necrosis of the SP. As fenestration of the SP is a secondary event associated with PICH syndrome, this condition should not be considered a contraindication for intrauterine repair of the spinal defect. Instead, it should be seen as an indicator of the severity of the intraventricular pressure.


Assuntos
Hidrocefalia , Hipotensão Intracraniana , Malformações do Sistema Nervoso , Disrafismo Espinal , Gravidez , Feminino , Humanos , Hipotensão Intracraniana/complicações , Encefalocele/diagnóstico por imagem , Encefalocele/epidemiologia , Encefalocele/complicações , Hidrocefalia/diagnóstico por imagem , Disrafismo Espinal/complicações , Feto/diagnóstico por imagem , Malformações do Sistema Nervoso/complicações , Idade Gestacional , Imageamento por Ressonância Magnética/métodos , Estudos Retrospectivos , Ultrassonografia Pré-Natal/métodos
14.
Materials (Basel) ; 14(20)2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34683793

RESUMO

Rice husks are a by-product that is generated in large quantities in Spain. However, they are not used efficiently. One of their possible applications is its thermal use in power generation equipment. For that purpose, it is important to know the characteristics of rice husks and their thermal behavior, as well as their possible pollutant emission to the atmosphere with respect to its thermal use as a biofuel. In this work, the thermal characteristics of rice husks and their thermal behavior were studied by using thermogravimetry and mass spectroscopy for two different atmospheres (oxidizing and inert). This way, the thermal profiles and the main characteristics were studied, as well as the emission of possible pollutants to the atmosphere, such as CO2, CH4, NO2, NH3, SO2, and H2S. Moreover, three different methods (FWO, KAS, and Starink) were used to carry out a thermal analysis, in order to obtain the main thermal parameters such as activation energy. The results of the analysis predicted that rice husks could be used as biofuel in industrial thermal equipment based on its acceptable calorific value, good thermal characteristics, and low gas emissions both in oxidizing and inert atmosphere (although they have a high ash content).

15.
Ultrasound ; 29(3): 193-198, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34567232

RESUMO

INTRODUCTION: Congenital hepatic cyst is a rare hepatobiliary malformation that can present as an asymptomatic, unilocular, upper abdominal cystic mass in the fetus. CASES: We report two cases of congenital hepatic cyst in which the diagnosis was made by prenatal ultrasound at 25 and 33 weeks' gestation. The diagnosis was confirmed postnatally by abdominal ultrasound and radiologic imaging studies. Although the infants remained asymptomatic, laparoscopic excision was performed due to the increasing size of the cyst in both cases. Pathological examination of the resected specimens confirmed a simple cyst in one case and an epidermoid cyst in the other. CONCLUSIONS: Our cases and those described in the literature demonstrate the usefulness of incidental prenatal detection of congenital hepatic cyst, especially during late pregnancy. Such a diagnosis can allow for proper perinatal surveillance, selection of the route of delivery, and timely postnatal surgical intervention if required.

16.
Cir Cir ; 89(3): 354-360, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34037613

RESUMO

INTRODUCCIÓN: Un trauma penetrante puede dañar una variedad de órganos. Dado que el hígado es un órgano sólido inelástico, no tiene la tolerancia al estiramiento necesaria para hacer frente a una herida por proyectil de arma de fuego (GSW). MÉTODOS: Este fue un estudio retrospectivo, observacional y descriptivo de 53 registros clínicos de pacientes ingresados en el Departamento de Cirugía por trauma hepático (LT) por un GSW. RESULTADOS: Del total de historias clínicas analizadas, el 89% de los pacientes presentaron una lesión asociada con LT. La lesión orgánica asociada más frecuente fue la torácica, específicamente la lesión pulmonar, en el 58%. El predictor más importante de mortalidad fue una estancia en la unidad de cuidados intensivos (UCI), que aumentó el riesgo unas 21 veces. CONCLUSIÓN: Una estadía en la UCI, seguida de la presencia de fracturas, fue el predictor más importante de mortalidad. Se necesitan nuevas medidas de pronóstico para contrarrestar las variables que ha creado el aumento de GSW, además de disminuir el tiempo de espera desde el evento traumático hasta el tratamiento relevante. INTRODUCTION: A penetrating trauma can damage a variety of organs. Since the liver is an inelastic solid organ, it does not have the necessary stretch tolerance to cope with a gunshot wound (GSW). METHODS: This was a retrospective, observational, and descriptive study of 53 clinical records of patients admitted to the Department of Surgery for liver trauma (LT) by a GSW. RESULTS: Of the total clinical records analyzed, 89% of the patients presented a lesion associated with LT. The most common associated organic lesion was thoracic, specifically lung injury, in 58%. The most important predictor of mortality was a stay in the intensive care unit (ICU), which increased the risk about 21 times. CONCLUSION: A stay in the ICU, followed by the presence of fractures, was the most important predictor of mortality. New prognostic measures are needed to counteract the variables that the increase in GSWs has created, in addition to decreasing the waiting time from the traumatic event to relevant treatment.


Assuntos
Ferimentos por Arma de Fogo , Humanos , Unidades de Terapia Intensiva , Fígado/cirurgia , Estudos Retrospectivos , Ferimentos por Arma de Fogo/cirurgia
17.
Plant Physiol Biochem ; 161: 191-199, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33621863

RESUMO

Embothrium coccineum produces cluster roots (CR) to acquire sparingly soluble phosphorus (P) from the soil through the exudation of organic compounds. However, the physiological mechanisms involved in carbon drainage through its roots, as well as the gene expression involved in the biosynthesis of carboxylates and P uptake, have not been explored. In this work, we evaluated the relationship between carboxylate exudation rate and phosphoenolpyruvate carboxylase (PEPC) activity in roots of E. coccineum seedlings grown in a nutrient-poor volcanic substrate. Second, we evaluated CR formation and the expression of genes involved in the production of carboxylates (PEPC) and P uptake (PHT1) in E. coccineum seedlings grown under three different P supplies in hydroponic conditions. Our results showed that the carboxylate exudation rate was higher in CR than in non-CR, which was consistent with the higher PEPC activity in CR. We found higher CR formation in seedlings grown at 5 µM of P supply, concomitant with a higher expression of EcPEPC and EcPHT1 in CR than in non-CR. Overall, mature CR of E. coccineum seedlings growing on volcanic substrates poor in nutrients modify their metabolism compared to non-CR, enhancing carboxylate biosynthesis and subsequent carboxylate exudation. Additionally, transcriptional responses of EcPEPC and EcPHT1 were induced simultaneously when E. coccineum seedlings were grown in P-limited conditions that favored CR formation. Our results showed, for the first time, changes at the molecular level in CR of a species of the Proteaceae family, demonstrating that these root structures are highly specialized in P mobilization and uptake.


Assuntos
Fósforo , Proteaceae , Expressão Gênica , Raízes de Plantas , Solo
19.
Cir Cir ; 89(1): 39-45, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33498070

RESUMO

BACKGROUND: Traumatic injuries represent 9.6% of the global surface of the disease and represent the third most common cause of death in adults and adolescents. Patients were admitted to the hospital presenting traumatic injuries, penetrating abdominal traumatism remains a major cause of morbidity and mortality. OBJECTIVE: To analyze the presentation, handling and development of patient's gunshot wound. METHOD: Retrospective, descriptive, observational study. It was reviewed from 2010-2015 in the statistics department of the University Hospital Dr. José E. González all patients diagnosed with firearm projectile injury in abdomen. RESULTS: Were admitted above an average of 1.22 ± 0.51 lesions, on a Glasgow coma scale of 13.59 ± 2.5, oxygen saturation of 96.2 ± 2.09, heart rate of 94.4 ± 20, respiratory rate of 22 ± 6 and shock degree of 1.5 ± 0.80. CONCLUSION: Vital signs and specific characteristics of the lesion are essential and useful for the prediction of mortality due to abdominal traumatism by firearm projectile, in addition to the quantification of wounds and associated organic lesions, these are being evaluated both as a whole and separately.


ANTECEDENTES: Las lesiones traumáticas representan el 9.6% de la carga global de la enfermedad y son la tercera causa más común de muerte en adultos y adolescentes. Entre los pacientes ingresados en el hospital con lesiones traumáticas, el traumatismo penetrante abdominal sigue siendo una importante causa de morbilidad y mortalidad. OBJETIVO: Analizar la presentación, el manejo y la evolución de los pacientes con herida por proyectil de arma de fuego en el abdomen. MÉTODO: Estudio retrospectivo, descriptivo y observacional. Se revisaron todos los pacientes con diagnóstico de herida por proyectil de arma de fuego en el abdomen en el departamento de estadística del Hospital Universitario Dr. José E. González durante los años 2010-2015. RESULTADOS: Del total, 21 (9.1%) pacientes eran del sexo femenino y 229 (90.9%) del sexo masculino. Se ingresaron con un promedio de 1.22 ± 0.51 lesiones, con una puntuación en la Escala de coma de Glasgow de 13.59 ± 2.5, saturación de oxígeno de 96.2 ± 2.09, frecuencia cardiaca de 94.4 ± 20, frecuencia respiratoria de 22 ± 6 y grado de choque de 1.5 ± 0.80. CONCLUSIÓN: Los signos vitales y las características específicas de la lesión son esenciales y útiles para la predicción de la mortalidad por traumatismo abdominal por proyectil de arma de fuego, además de la cuantificación de heridas y lesiones orgánicas asociadas, siendo evaluadas estas tanto en un todo como por separado.


Assuntos
Traumatismos Abdominais , Ferimentos por Arma de Fogo , Abdome , Traumatismos Abdominais/epidemiologia , Traumatismos Abdominais/cirurgia , Adolescente , Adulto , Humanos , México/epidemiologia , Nigéria , Estudos Retrospectivos , Violência , Ferimentos por Arma de Fogo/epidemiologia , Ferimentos por Arma de Fogo/cirurgia
20.
Prenat Diagn ; 41(8): 942-948, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33480068

RESUMO

OBJECTIVE: To investigate the role of the interpeduncular angle (IPA) as a new indicator of intracranial hypotension in fetuses with open spinal dysraphism (SD). METHODS: Two groups of fetuses undergoing magnetic resonance imaging (MRI) examination were identified. The study group included fetuses with open SD (n = 21), while the control group included fetuses with a normal brain and spine (n = 43). Two observers retrospectively evaluated axial T2-weighted images of the brain and the IPA was identified and measured. Other features of the Chiari II malformation were also evaluated in the study group and correlated with the IPA. RESULTS: The average value (±SD) of the IPA for the study and control groups was 9.8° ± 18.5° and 60.2° ± 5.9°, respectively. The intergroup analysis of the IPA measurements revealed a statistically significant difference between the groups (p < 0.005). Brainstem slumping or cerebellar tonsillar descent, collapse of the fourth ventricle, and ventriculomegaly also had a significant correlation with a lower IPA (p = 0.001). CONCLUSION: Measuring the IPA may be a useful technique for assessing the degree of intracranial hypotension in fetuses with open SD. This technique can also detect less severe cases of prenatal intracranial hypotension, even before cerebellar tonsillar descent. The lower IPA in fetuses with open SD further supports the theory that cerebrospinal fluid leakage, and not traction, is the underlying cause of Chiari II malformation.


Assuntos
Feto/fisiopatologia , Hipotensão Intracraniana/classificação , Disrafismo Espinal/cirurgia , Adulto , Malformação de Arnold-Chiari/classificação , Malformação de Arnold-Chiari/complicações , Malformação de Arnold-Chiari/cirurgia , Feminino , Feto/cirurgia , Humanos , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Gravidez , Estudos Retrospectivos , Disrafismo Espinal/classificação
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