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1.
Niger J Clin Pract ; 27(4): 534-536, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38679778

RESUMO

ABSTRACT: A femoral hernia is an uncommon and acquired hernia in the groin. Its incidence in adults is 2%-8% of all abdominal wall hernias, and it has a female-to-male ratio of 1.8:1. It is usually found in elderly patients and is associated with increased morbidity due to delays in diagnosis leading to a high incidence of incarceration and strangulation. Accurate preoperative diagnosis of femoral hernia is challenging, especially in obese patients in whom a small femoral hernia can be hidden under the groin fat. Unlike an inguinal hernia, it rarely reduces on its own and if asymptomatic and small, is often unnoticed by the elderly obese patient. Femoral hernia is often unsuspected and overlooked in males as it is predominant among females. Delay in diagnosis can lead to intestinal gangrene and high morbidity. We present a case of an incarcerated left femoral hernia in an elderly obese male who presented with acute intestinal obstruction. He was managed with resection of the gangrenous segment and double barrel ileostomy. Although uncommon in males, a femoral hernia has a high incidence of strangulation, and therefore should always be ruled out as a cause of acute intestinal obstruction in elderly patients. Therefore, never forget to examine the groin in case of intestinal obstruction.


Assuntos
Hérnia Femoral , Obstrução Intestinal , Humanos , Hérnia Femoral/cirurgia , Hérnia Femoral/diagnóstico , Hérnia Femoral/complicações , Masculino , Obstrução Intestinal/etiologia , Obstrução Intestinal/diagnóstico , Obstrução Intestinal/cirurgia , Idoso , Tomografia Computadorizada por Raios X , Obesidade/complicações , Gangrena/diagnóstico , Gangrena/cirurgia , Diagnóstico Diferencial
2.
Appl Radiat Isot ; 204: 111140, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38070360

RESUMO

Double differential neutron fluence distributions were measured in the 7Li(p,n)7Be reaction for proton beam energies 7, 9 and 12 MeV. Seven liquid scintillator based detectors were employed to measure neutron fluence distributions using the Time of Flight technique. Neutron ambient dose equivalents were determined from the measured fluence distribution using ICRP (International Commission on Radiological Protection) recommended fluence to dose equivalent conversion coefficients. Neutron dose equivalents were also measured using a conventional BF3 detector based REM counter. Ambient dose equivalent measured by the REM counter is found to be in agreement with that determined from the neutron fluence spectra within their uncertainties. Angular distributions of the ambient dose equivalents were also determined from the measured fluence distributions at different angles.

4.
Braz J Biol ; 83: e275598, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37971087

RESUMO

The Bacalar Lagoon (BL) in Quintana Roo, Mexico; is an area of high interest due to its tourist potential. However, the changes in landuse patterns, urbanization, extensive cattle ranching and rapidly expanding agriculture, have generated negative impacts on areas of adjacent plan communities and wildlife habitats. The objective of this study has to evaluate the level of vegetation conservation in the southern portion of the BL through the avifauna present in sites with contrasting degrees of conservation. Additionally, change "and their habitat preference(s) in the different communities" to and their habitat use preferences in the different communities. To evaluate the level of conservation of the BL, field visits and botanical collections were carried out to identify species. For the counting and identification of birds, monthly surveys were made through coastal tours along the cenote Xul-ha in 2.5 km transects. Four transects were established: two for sites characterized as semi-conserved and two with disturbed sites. A total richness of 40 taxa was observed, which corresponds to 8.1% of the Quintana Roo avifauna and 32% to wetland birds (125 species). The species accumulation curves indicated that semi-conserved and disturbed sites tend to reach asymptotes and with a coverage percentage greater than 90%. In terms of diversity and community structure, no significant differences were observed. However, the semi-conserved and disturbed sites each have 11 unique species and share 18 species. The LB has an intermediate diversity of bird species compared to studies at the Mexican level, the habitat is important for the conservation of birdlife; as it functions as a reservoir of diversity. Strategies has been suggested that promote sustainable tourism, support the restoration of natural vegetation; and facilitate the economic development of the region.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Animais , Bovinos , México , Ecossistema , Animais Selvagens , Aves
5.
Nat Struct Mol Biol ; 30(11): 1628-1639, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37770717

RESUMO

To understand how the nucleosome remodeling and deacetylase (NuRD) complex regulates enhancers and enhancer-promoter interactions, we have developed an approach to segment and extract key biophysical parameters from live-cell three-dimensional single-molecule trajectories. Unexpectedly, this has revealed that NuRD binds to chromatin for minutes, decompacts chromatin structure and increases enhancer dynamics. We also uncovered a rare fast-diffusing state of enhancers and found that NuRD restricts the time spent in this state. Hi-C and Cut&Run experiments revealed that NuRD modulates enhancer-promoter interactions in active chromatin, allowing them to contact each other over longer distances. Furthermore, NuRD leads to a marked redistribution of CTCF and, in particular, cohesin. We propose that NuRD promotes a decondensed chromatin environment, where enhancers and promoters can contact each other over longer distances, and where the resetting of enhancer-promoter interactions brought about by the fast decondensed chromatin motions is reduced, leading to more stable, long-lived enhancer-promoter relationships.


Assuntos
Cromatina , Nucleossomos , Complexo Mi-2 de Remodelação de Nucleossomo e Desacetilase/metabolismo , Regiões Promotoras Genéticas , Elementos Facilitadores Genéticos
6.
Niger J Clin Pract ; 26(1): 128-131, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36751835

RESUMO

A transmesenteric internal hernia (TIH) is a protrusion of a viscus through the mesenteric defect. It is secondary to previous gastrointestinal surgery in an adult. Early diagnosis and management are warranted to prevent the strangulation of the bowel in a TIH. Here, we are reporting a case of a 24-year-old gentleman with COVID-positive status who has presented with cough, abdominal cocoon, and features of subacute intestinal obstruction (SAIO) without any previous history of abdominal surgery. A nonoperative trial is given in the management of abdominal cocoon with SAIO. In contrast, delay in surgical intervention in TIH leads to bowel gangrene. Surprisingly even on contrast-enhanced computed tomography of the abdomen, TIH was not picked up. We have diagnosed this case intraoperatively with gangrene of the bowel. In an abdominal cocoon without any history suggestive of tuberculosis or previous surgery, or any other condition that leads to an intra-abdominal reaction, an internal hernia should be kept as a differential diagnosis. The delay in diagnosis and surgical intervention is associated with potentially disastrous complications.


Assuntos
COVID-19 , Hérnia Abdominal , Obstrução Intestinal , Masculino , Adulto , Humanos , Adulto Jovem , Gangrena , COVID-19/complicações , Hérnia Abdominal/complicações , Hérnia Abdominal/diagnóstico , Hérnia Abdominal/cirurgia , Obstrução Intestinal/etiologia , Hérnia Interna/complicações , Mesentério/cirurgia
7.
Immunohematology ; 38(3): 100-105, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36190198

RESUMO

Despite knowing the benefits of the type and screen (TS) method in pre-transfusion testing (PTT), most transfusion centers in developing countries continue to be reluctant to adopt a TS strategy over the conventional type and antihuman globulin (AHG) crossmatch (TX) policy in their routine laboratory practice because of the cost of obtaining antibody screening reagents. To generate strong evidence, this multicenter, observational study was conducted in which we collected data prospectively over a 1-year period from six major blood centers in India. The primary objective of this study was to identify the discordance between TS and TX results. A secondary objective was to identify the allo-antibody specificity in patients with positive antibody detection tests. All patients with orders for red blood cell transfusion who met patient selection criteria were subjected to parallel testing by column agglutination technology (CAT) for both the antibody detection test (screen) using a commercial three-cell panel and for the AHG crossmatch. A total of 21,842 patients were tested. In 148 patients with incompatible crossmatches, samples from six patients gave negative results with the antibody detection test, whereas the antibody detection test was positive in samples from 118 patients among the 21,694 crossmatch-compatible cases. The TS approach achieved a positive percent agreement of 95.95 and was found to be significantly effective in preventing the transfusion of serologically incompatible blood. The risk associated with abbreviating the AHG crossmatch was found to be 0.009 percent. Most of the identified clinically significant alloantibodies were directed to Rh antigens (D>E>c>C>e), followed by anti-K and anti-M. This study has generated sufficient robust data for the Indian population by including patients from all major geographical areas of the country and concluded a satisfactory agreement level as well as non-inferiority to the current PTT policy. Therefore, TS policy can be implemented in developing countries with no compromise on blood safety, provided sufficient technical and infrastructural support are available.


Assuntos
Antígenos de Grupos Sanguíneos , Isoanticorpos , Tipagem e Reações Cruzadas Sanguíneas , Transfusão de Sangue , Humanos , Políticas
8.
Nat Microbiol ; 7(9): 1337-1347, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35927336

RESUMO

Early development of the microbiome has been shown to affect general health and physical development of the infant and, although some studies have been undertaken in high-income countries, there are few studies from low- and middle-income countries. As part of the BARNARDS study, we examined the rectal microbiota of 2,931 neonates (term used up to 60 d) with clinical signs of sepsis and of 15,217 mothers screening for blaCTX-M-15, blaNDM, blaKPC and blaOXA-48-like genes, which were detected in 56.1%, 18.5%, 0% and 4.1% of neonates' rectal swabs and 47.1%, 4.6%, 0% and 1.6% of mothers' rectal swabs, respectively. Carbapenemase-positive bacteria were identified by MALDI-TOF MS and showed a high diversity of bacterial species (57 distinct species/genera) which exhibited resistance to most of the antibiotics tested. Escherichia coli, Klebsiella pneumoniae and Enterobacter cloacae/E. cloacae complex, the most commonly found isolates, were subjected to whole-genome sequencing analysis and revealed close relationships between isolates from different samples, suggesting transmission of bacteria between neonates, and between neonates and mothers. Associations between the carriage of antimicrobial resistance genes (ARGs) and healthcare/environmental factors were identified, and the presence of ARGs was a predictor of neonatal sepsis and adverse birth outcomes.


Assuntos
Microbioma Gastrointestinal , Sepse , Antibacterianos , Países em Desenvolvimento , Resistência Microbiana a Medicamentos , Escherichia coli , Feminino , Humanos , Lactente , Recém-Nascido , Testes de Sensibilidade Microbiana , Mães
10.
Ann R Coll Surg Engl ; 104(9): e252-e254, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35446709

RESUMO

Afferent loop syndrome (ALS) is an uncommon complication of gastrojejunostomy. It may be acute or chronic depending on whether symptoms manifest within 7 days of surgery. Rarely acute ALS may give rise to acute pancreatitis. It may present early in the postoperative course and, if diagnosed late, may result in organ failure within 48h. We report a middle-aged woman with carcinoma of the stomach managed by subtotal gastrectomy with Billroth II gastrojejunostomy and Braun jejunojejunostomy. The patient developed vomiting and abdominal pain in the first postoperative day with acute renal shutdown and about 500ml drain output of dirty fluid. On investigation, a diagnosis of acute pancreatitis due to afferent loop syndrome was made, and the patient was resuscitated in the intensive care unit. However, she showed early signs of organ failure and succumbed to her condition within 6 days of surgery. Since the complication is rare following gastrojejunostomy and often mimics ALS, an early diagnosis becomes difficult. If delay in management happens, premature organ failure may lead to high morbidity and mortality.


Assuntos
Síndrome da Alça Aferente , Derivação Gástrica , Pancreatite , Neoplasias Gástricas , Feminino , Humanos , Pessoa de Meia-Idade , Doença Aguda , Síndrome da Alça Aferente/diagnóstico , Síndrome da Alça Aferente/etiologia , Síndrome da Alça Aferente/cirurgia , Gastrectomia/efeitos adversos , Derivação Gástrica/efeitos adversos , Pancreatite/etiologia , Pancreatite/complicações , Período Pós-Operatório , Neoplasias Gástricas/cirurgia , Neoplasias Gástricas/complicações
11.
Appl Physiol Nutr Metab ; 47(7): 749-761, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35358395

RESUMO

The onset of menopause and accompanying changes to ovarian hormones often precedes endothelial dysfunction in women. In particular, accelerated impairments in macrovascular and microvascular function coincide with the loss of estrogen, as does impaired endothelial responses to ischemia-reperfusion (IR) injury. In healthy, early postmenopausal women (n = 12; 3.9 ± 1.5 years since menopause) we tested the hypothesis that acute dietary nitrate (NO3-) supplementation would improve endothelial function and attenuate the magnitude of endothelial dysfunction following whole-arm IR in comparison with placebo. In this randomized, double-blind, placebo-controlled, crossover study we tested participants before and after NO3--rich (BRnitrate) and NO3--depleted (BRplacebo) beetroot juice (BR) consumption, as well as following IR injury, and 15 min after IR to assess recovery. Analyses with repeated-measures general linear models revealed a condition × time interaction for brachial artery flow-mediated dilation (FMD; P = 0.04), and no interaction effect was found for the near-infrared spectroscopy-derived reperfusion slope (P = 0.86). Follow-up analysis showed a significant decline in FMD following IR injury with BRplacebo in comparison with all other timepoints (all, P < 0.05), while this decline was not present with BRnitrate (all, P > 0.05). Our findings demonstrate that a single dose of dietary NO3- minimizes IR-induced macrovascular endothelial dysfunction in healthy, early postmenopausal women, but does not improve resting macrovascular and microvascular function. Trial registration number: NCT03644472. Novelty: In healthy, early postmenopausal women, a single dose of NO3--rich BR can protect against IR-induced endothelial dysfunction. This protection may be due to nitric oxide bioactivity during IR rather than improved endothelial function prior to the IR protocol per se.


Assuntos
Nitratos , Traumatismo por Reperfusão , Estudos Cross-Over , Suplementos Nutricionais , Método Duplo-Cego , Endotélio Vascular/fisiologia , Feminino , Humanos , Óxido Nítrico/farmacologia , Pós-Menopausa , Traumatismo por Reperfusão/prevenção & controle
12.
Ann R Coll Surg Engl ; 104(2): 117-120, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35100852

RESUMO

INTRODUCTION: The ear, nose and throat (ENT) emergency clinic is managed by foundation year (FY) doctors from taking referrals to discharging patients, under the supervision of a registrar. FYs learn essential skills and knowledge on how to manage common ENT problems. The clinic is often overloaded because of a high patient demand, and this limits the opportunities for teaching. We hypothesised that the clinic bookings would be better managed if referrals from general practitioners (GPs) were triaged by registrars. METHODS: Telephone referrals from GPs for the ENT emergency clinic were directed to the on-call ENT registrar, between 8am and 1pm from Monday to Friday, and to the FY outside of this period. Consecutive referrals to the emergency clinic were analysed in a baseline audit and a post-intervention cycle. RESULTS: A total of 646 and 611 patients were given clinic appointments in the first and second cycles, respectively. Clinic session overbookings decreased from 85% to 46.3%. Appointments for referrals that were deemed inappropriate had reduced from 22% to 12.1%. DISCUSSION AND CONCLUSION: Involvement of a registrar in taking referrals for the ENT emergency clinic was associated with a reduction in clinic overbookings. It is feasible and productive to involve a senior decision maker in the operational management of the emergency clinic, while preserving the delivery of this service by FYs for its training value.


Assuntos
Instituições de Assistência Ambulatorial , Serviço Hospitalar de Emergência , Encaminhamento e Consulta/estatística & dados numéricos , Triagem , Auditoria Clínica , Clínicos Gerais , Humanos , Otorrinolaringologistas , Estudos Retrospectivos , Reino Unido
13.
AJNR Am J Neuroradiol ; 43(1): 125-131, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34764083

RESUMO

BACKGROUND AND PURPOSE: Gamma-aminobutyric acid and glutamate system disruptions may underlie neonatal brain injury. However, in vivo investigations are challenged by the need for special 1H-MR spectroscopy sequences for the reliable measurement of the neurotransmitters in this population. We used J-edited 1H-MR spectroscopy (Mescher-Garwood point-resolved spectroscopy) to quantify regional in vivo gamma-aminobutyric acid and glutamate concentrations during the early postnatal period in healthy neonates. MATERIALS AND METHODS: We prospectively enrolled healthy neonates and acquired Mescher-Garwood point-resolved spectroscopy spectra on a 3T MR imaging scanner from voxels located in the cerebellum, the right basal ganglia, and the right frontal lobe. CSF-corrected metabolite concentrations were compared for regional variations and cross-sectional temporal trends with advancing age. RESULTS: Fifty-eight neonates with acceptable spectra acquired at postmenstrual age of 39.1 (SD, 1.3) weeks were included for analysis. Gamma-aminobutyric acid (+ macromolecule) (2.56 [SD, 0.1]) i.u., glutamate (3.80 [SD, 0.2]), Cho, and mIns concentrations were highest in the cerebellum, whereas NAA (6.72 [SD, 0.2]), NAA/Cho, Cr/Cho, and Glx/Cho were highest in the basal ganglia. Frontal gamma-aminobutyric acid (1.63 [SD, 0.1]), Glx (4.33 [SD, 0.3]), Cr (3.64 [SD, 0.2]), and Cho concentrations were the lowest among the ROIs. Glx, NAA, and Cr demonstrated a significant adjusted increase with postmenstrual age (ß = 0.2-0.35), whereas gamma-aminobutyric acid and Cho did not. CONCLUSIONS: We report normative regional variations and temporal trends of in vivo gamma-aminobutyric acid and glutamate concentrations reflecting the functional and maturational status of 3 distinct brain regions of the neonate. These measures will serve as important normative values to allow early detection of subtle neurometabolic alterations in high-risk neonates.


Assuntos
Ácido Glutâmico , Ácido gama-Aminobutírico , Ácido Aspártico/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Estudos Transversais , Ácido Glutâmico/metabolismo , Humanos , Lactente , Recém-Nascido , Espectroscopia de Ressonância Magnética/métodos , Ácido gama-Aminobutírico/metabolismo
14.
Ann R Coll Surg Engl ; 104(2): 117-120, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34813383

RESUMO

INTRODUCTION: The ear, nose and throat (ENT) emergency clinic is managed by foundation year (FY) doctors from taking referrals to discharging patients, under the supervision of a registrar. FYs learn essential skills and knowledge on how to manage common ENT problems. The clinic is often overloaded because of a high patient demand, and this limits the opportunities for teaching. We hypothesised that the clinic bookings would be better managed if referrals from general practitioners (GPs) were triaged by registrars. METHODS: Telephone referrals from GPs for the ENT emergency clinic were directed to the on-call ENT registrar, between 8am and 1pm from Monday to Friday, and to the FY outside of this period. Consecutive referrals to the emergency clinic were analysed in a baseline audit and a post-intervention cycle. RESULTS: A total of 646 and 611 patients were given clinic appointments in the first and second cycles, respectively. Clinic session overbookings decreased from 85% to 46.3%. Appointments for referrals that were deemed inappropriate had reduced from 22% to 12.1%. DISCUSSION AND CONCLUSION: Involvement of a registrar in taking referrals for the ENT emergency clinic was associated with a reduction in clinic overbookings. It is feasible and productive to involve a senior decision maker in the operational management of the emergency clinic, while preserving the delivery of this service by FYs for its training value.


Assuntos
Pacientes Ambulatoriais , Triagem , Instituições de Assistência Ambulatorial , Humanos , Nariz , Encaminhamento e Consulta
16.
Global Biogeochem Cycles ; 35(6): e2021GB007000, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34219915

RESUMO

We study the drivers behind the global atmospheric methane (CH4) increase observed after 2006. Candidate emission and sink scenarios are constructed based on proposed hypotheses in the literature. These scenarios are simulated in the TM5 tracer transport model for 1984-2016 to produce three-dimensional fields of CH4 and δ 13C-CH4, which are compared with observations to test the competing hypotheses in the literature in one common model framework. We find that the fossil fuel (FF) CH4 emission trend from the Emissions Database for Global Atmospheric Research 4.3.2 inventory does not agree with observed δ 13C-CH4. Increased FF CH4 emissions are unlikely to be the dominant driver for the post-2006 global CH4 increase despite the possibility for a small FF emission increase. We also find that a significant decrease in the abundance of hydroxyl radicals (OH) cannot explain the post-2006 global CH4 increase since it does not track the observed decrease in global mean δ 13C-CH4. Different CH4 sinks have different fractionation factors for δ 13C-CH4, thus we can investigate the uncertainty introduced by the reaction of CH4 with tropospheric chlorine (Cl), a CH4 sink whose abundance, spatial distribution, and temporal changes remain uncertain. Our results show that including or excluding tropospheric Cl as a 13 Tg/year CH4 sink in our model changes the magnitude of estimated fossil emissions by ∼20%. We also found that by using different wetland emissions based on a static versus a dynamic wetland area map, the partitioning between FF and microbial sources differs by 20 Tg/year, ∼12% of estimated fossil emissions.

17.
Semin Fetal Neonatal Med ; 26(4): 101268, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34301501

RESUMO

Adequate nutrition and glycemic homeostasis are increasingly recognized as potentially neuroprotective for the developing brain. In the context of hypoxia-ischemia, evidence is scarce regarding optimal nutritional support and administration route, as well as the short- and long-term consequences of such interventions. In this review, we summarize current knowledge on disturbances of brain metabolism of glucose and substrates by hypoxia-ischemia, and compound effects of these mechanisms on brain injury characterized by specific patterns on EEG and MRI. Risks and benefits of nutrition delivery via parenteral or enteral routes are examined. Nutrition could mitigate adverse neurodevelopmental outcomes, and the impact of nutritional strategies and specific nutritional interventions are reviewed. Limited literature highlights the need for further studies to understand the changes in energy metabolism during and after hypoxic-ischemic injury, to optimize nutritional regimens and glucose management, and to inform the neuroprotective role of nutrition.


Assuntos
Lesões Encefálicas , Hipotermia Induzida , Hipotermia , Hipóxia-Isquemia Encefálica , Glicemia , Humanos , Hipóxia-Isquemia Encefálica/terapia , Recém-Nascido
18.
Biosystems ; 206: 104450, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34098060

RESUMO

In this paper, we have developed a multi-scale, lattice-free, agent based model of avascular tumour growth in epithelial tissue. The model integrates different events to identify the underlying diversity within intracellular, cellular, and extracellular layer dynamics. The model considers every cell as an agent. A cellular agent may proliferate, spawns two identical daughter agents, or it may be transformed into other phenotypes during its life time depending on its internal proteins' activity as well as its external microenvironment. In this context, a simplified age-structured cell cycle model is adopted from the existing literature. The model considers that the intracellular events are regulated by p27 gene expression. In this model, p27 protein controls the overall tumour growth dynamics. Moreover, p27 is controlled by the external oxygen and nutrients that are modelled with the reaction-diffusion equations. The model also considers several biophysical forces which directly effect on the tumour growth dynamics. This modelling framework offers biologically realistic outcomes and also covers important criteria of the hallmarks of cancer which include oxygen and nutrient consumptions, micro-environmental heterogeneity, tumour cell proliferation by avoiding growth suppressor signals, replication of tumour cells at an abnormally faster rate, and resistance of apoptosis. The avascular tumour growth model is validated with immunohistochemistry and histopathology data. The outcome of the proposed model is very close to the range of the patient data, which concludes that the model is capable enough to mimic these complex biophysical phenomena.


Assuntos
Proliferação de Células/fisiologia , Simulação por Computador , Modelos Biológicos , Neoplasias/patologia , Microambiente Tumoral/fisiologia , Humanos , Neoplasias/metabolismo
19.
Immunohematology ; 37(1): 25-32, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33962486

RESUMO

Determination of accurate anti-A/-B titers is important for treatment selection in ABO-incompatible stem cell and solid-organ transplants. The standard method for ABO antibody titration is the conventional tube test (CTT). Dithiothreitol (DTT) is commonly used to inactivate the IgM antibody component. The aim of this study was to compare six different methods for ABO antibody titration and to observe the effectiveness of DTT on antibody estimation. A total of 90 healthy voluntary blood donors were enrolled in this study, including 30 each for blood groups A, B, and O. Antibody titrations were performed and tested using the CTT-immediate spin (IS), CTT-antihuman globulin (AHG) with and without DTT, column agglutination technology (CAT)-IS, and CAT-AHG with and without DTT methods. Bead-CAT was used, and the positive cutoff value was set to 1+ for each method to determine the endpoint of the titer. The median values of anti-A/-B titers by IS were found to be higher than those values by AHG in CTT and CAT among group B and A individuals, whereas no statistically significant differences were observed in values from group O individuals for IS and AHG anti-A/-B titers, estimated by each method. Although there was positive correlation between the anti-A/-B titer results obtained using the CTT and CAT in all blood groups, testing using AHG showed poor agreement with and without DTT pretreatment (kappa value of 0.11 and 0.20, respectively). Moderate agreement was observed between CTT-IS and CAT-IS (kappa value of 0.46). Median anti-A/-B AHG titers were reduced by the use of DTT in all blood group samples. Significant differences in the interpretability of anti-A/-B titers were observed among different methods. A uniform approach for selecting the method for ABO antibody titration is highly recommended, and DTT pretreatment of plasma to neutralize IgM activity should be considered to obtain precise values of IgG anti-A/-B titers. Immunohematology 2021;37:25-32 .Determination of accurate anti-A/-B titers is important for treatment selection in ABO-incompatible stem cell and solid-organ transplants. The standard method for ABO antibody titration is the conventional tube test (CTT). Dithiothreitol (DTT) is commonly used to inactivate the IgM antibody component. The aim of this study was to compare six different methods for ABO antibody titration and to observe the effectiveness of DTT on antibody estimation. A total of 90 healthy voluntary blood donors were enrolled in this study, including 30 each for blood groups A, B, and O. Antibody titrations were performed and tested using the CTT-immediate spin (IS), CTT-antihuman globulin (AHG) with and without DTT, column agglutination technology (CAT)-IS, and CAT-AHG with and without DTT methods. Bead-CAT was used, and the positive cutoff value was set to 1+ for each method to determine the endpoint of the titer. The median values of anti-A/-B titers by IS were found to be higher than those values by AHG in CTT and CAT among group B and A individuals, whereas no statistically significant differences were observed in values from group O individuals for IS and AHG anti-A/-B titers, estimated by each method. Although there was positive correlation between the anti-A/-B titer results obtained using the CTT and CAT in all blood groups, testing using AHG showed poor agreement with and without DTT pretreatment (kappa value of 0.11 and 0.20, respectively). Moderate agreement was observed between CTT-IS and CAT-IS (kappa value of 0.46). Median anti-A/-B AHG titers were reduced by the use of DTT in all blood group samples. Significant differences in the interpretability of anti-A/-B titers were observed among different methods. A uniform approach for selecting the method for ABO antibody titration is highly recommended, and DTT pretreatment of plasma to neutralize IgM activity should be considered to obtain precise values of IgG anti-A/-B titers. Immunohematology 2021;37:25­32 .


Assuntos
Sistema ABO de Grupos Sanguíneos , Testes Imunológicos , Aglutinação , Humanos , Índia , Tecnologia
20.
Sci Rep ; 10(1): 18936, 2020 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-33144615

RESUMO

Transplantation of peripheral nervous system glia is being explored for treating neural injuries, in particular central nervous system injuries. These glia, olfactory ensheathing cells (OECs) and Schwann cells (SCs), are thought to aid regeneration by clearing necrotic cells, (necrotic bodies, NBs), as well as myelin debris. The mechanism by which the glia phagocytose and traffic NBs are not understood. Here, we show that OECs and SCs recognize phosphatidylserine on NBs, followed by engulfment and trafficking to endosomes and lysosomes. We also showed that both glia can phagocytose and process myelin debris. We compared the time-course of glial phagocytosis (of both NBs and myelin) to that of macrophages. Internalization and trafficking were considerably slower in glia than in macrophages, and OECs were more efficient phagocytes than SCs. The two glial types also differed regarding their cytokine responses after NB challenge. SCs produced low amounts of the pro-inflammatory cytokine TNF-α while OECs did not produce detectable TNF-α. Thus, OECs have a higher capacity than SCs for phagocytosis and trafficking, whilst producing lower amounts of pro-inflammatory cytokines. These findings suggest that OEC transplantation into the injured nervous system may lead to better outcomes than SC transplantation.


Assuntos
Fagocitose/fisiologia , Células de Schwann/metabolismo , Animais , Western Blotting , Morte Celular/genética , Morte Celular/fisiologia , Imunofluorescência , Macrófagos/metabolismo , Camundongos , Camundongos Transgênicos , Neuroglia/citologia , Neuroglia/metabolismo , Neurociências , Fagocitose/genética , Fosfatidilserinas/metabolismo
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