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1.
Cureus ; 16(7): e64803, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39156394

RESUMO

A proliferating trichilemmal tumor (PTT) is a rare, benign, exophytic tumor originating from the isthmus region of the outer root sheath of the hair follicle. Clinically, PTTs manifest as isolated, exophytic, firm nodules that have the potential to ulcerate. These tumors may occasionally originate from a pre-existing trichilemmal cyst, or they can emerge spontaneously. Most exclusively these lesions are seen on the scalp. However, rarely these tumors can be found in other anatomical areas. Our patient had a protruding mass in her shoulder for 20 years, and this is a rare site for the occurrence of these lesions; it could be the first case to document such a site, as far as we found in the literature. The mainstay treatment of the PTT is surgical excision of the tumor, assessing the histological margins to ensure sufficient resection was made, close monitoring, and follow-up with the patient.

2.
J Nucl Med Technol ; 51(4): 296-301, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37433678

RESUMO

The objective was to compare estimated total blood-absorbed doses obtained by applying 4 methods to the same group of patients. In addition, these results were compared with those for the patients of other researchers, who used various other techniques over a period of more than 20 y. Methods: Twenty-seven patients (22 women and 5 men) with differentiated thyroid carcinoma were enrolled in the study. Whole-body measurements were performed as conjugate-view (anterior and posterior) counts by scintillation camera imaging. All patients received 3.7 GBq of 131I for thyroid ablation. Results: The mean total blood-absorbed doses by the first, second, third, and fourth methods in the 27 patients were estimated to be 0.46 ± 0.12, 0.45 ± 0.13, 0.46 ± 0.19, and 0.62 ± 0.23 Gy, respectively. The maximum values were 1.40, 0.81, 1.04. and 1.33 Gy, respectively. The difference between the mean values was 37.22%. In the comparison with the total blood-absorbed doses for the patients of other researchers, the difference was 50.77% (difference between the means of 0.65 and 0.32 Gy). Conclusion: None of the total absorbed doses to the blood by the 4 methods in my 27 patients was 2 Gy, the maximum permissible dose. The difference between the total absorbed doses to the blood obtained by different teams of researchers was 50.77%, whereas the difference between the values by the 4 different methods in the 27 patients was 37.22%.


Assuntos
Adenocarcinoma , Neoplasias da Glândula Tireoide , Masculino , Humanos , Feminino , Dosagem Radioterapêutica , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/radioterapia , Radioisótopos do Iodo/uso terapêutico
3.
Prev Vet Med ; 215: 105922, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37084631

RESUMO

Listeria monocytogenes is a significant pathogen that causes listeriosis in humans and small ruminants. This study aimed to estimate the prevalence, antimicrobial resistance and risk factors of L. monocytogenes in small dairy ruminants in Jordan. A total of 948 milk samples were collected from 155 sheep and goat flocks across Jordan. L. monocytogenes was isolated from the samples, confirmed and tested for 13 clinically important antimicrobials. Data were also collected on the husbandry practices to identify risk factors for the presence of L. monocytogenes. The results showed that the flock-level prevalence of L. monocytogenes was 20.0% (95% CI; 14.46%-26.99%) and the prevalence in the individual milk samples was 6.43% (95% CI; 4.92%-8.36%). The univariable (UOR=2.65, p = 0.021) and multivariable (AOR=2.49, p = 0.028) analyses showed that using water from municipality pipelines as a water source in the flock reduced L. monocytogenes prevalence. All L. monocytogenes isolates were resistant to at least one antimicrobial. High percentages of the isolates were resistant to ampicillin (83.6%), streptomycin (79.3%), kanamycin (75.0%), quinupristin/dalfopristin (63.8%) and clindamycin (61.2%). About 83.6% of the isolates (94.2% and 75% of the sheep and goat isolates) exhibited multidrug resistance (resistance to ≥3 antimicrobial classes). In addition, the isolates exhibited fifty unique antimicrobial resistance profiles. Thus, it's recommended to restrict the misuse of clinically important antimicrobials and to chlorinate and monitor the water sources in sheep and goat flocks.


Assuntos
Listeria monocytogenes , Humanos , Ovinos , Animais , Cabras , Jordânia/epidemiologia , Ruminantes , Resistência a Múltiplos Medicamentos , Antibacterianos/farmacologia
4.
Radiography (Lond) ; 29(3): 604-609, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37075490

RESUMO

INTRODUCTION: Paediatric patients differ from adult patients with respect to anatomy, examination factors, behaviour, and intellectual development, requiring dedicated specialised knowledge and expertise. In the absence of a formal dedicated paediatric medical imaging subspecialty, this study undertook to understand student radiographers' experiences and perspectives on paediatric medical imaging. METHODS: The study entailed a descriptive cross-sectional survey design entailed a 51-item closed and open-ended response questionnaire using a total sampling method. Data were collected from both under- and postgraduate student radiographers who undertook clinical placement. Data interpretation and analysis involved statistical analysis of close-ended questions and thematic analysis of open-ended questions. RESULTS: The overall response rate was 70%. Most participants acknowledged the importance of dedicated paediatric content as well as the theory content covered. The shortcoming in pre-placement practical component was overcome through varied approaches like observations and attempting through supervision whilst experiencing uncertainty, anxiety and felt unfair to risk the patient. As reported in literature like their qualified counterparts expressed similar challenges in technique adaptation, styles of interactions in gaining cooperation from both the children and parents. They also felt paediatric content and the practicals should be embedded throughout the course offering to not compromise the day-to-day service delivery. CONCLUSIONS: The study findings iterate the importance paediatric imaging in the service delivery context. The importance of undertaking these examinations reliant on experiential learning is insufficient to bridge the gap of preparation prior to placement. IMPLICATIONS FOR PRACTICE: Collaborative academic and clinical radiography education will ensure that radiography students' dedicated specialised paediatric imaging knowledge and experience are enhanced.


Assuntos
Radiologia , Estudantes de Medicina , Criança , Humanos , Austrália , Estudos Transversais , Radiografia , Radiologia/educação
5.
PLoS One ; 18(2): e0280481, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36827358

RESUMO

Craniofacial defects require a treatment approach that provides both robust tissues to withstand the forces of mastication and high geometric fidelity that allows restoration of facial architecture. When the surrounding soft tissue is compromised either through lack of quantity (insufficient soft tissue to enclose a graft) or quality (insufficient vascularity or inducible cells), a vascularized construct is needed for reconstruction. Tissue engineering using customized 3D printed bioreactors enables the generation of mechanically robust, vascularized bony tissues of the desired geometry. While this approach has been shown to be effective when utilized for reconstruction of non-load bearing ovine angular defects and partial segmental defects, the two-stage approach to mandibular reconstruction requires testing in a large, load-bearing defect. In this study, 5 sheep underwent bioreactor implantation and the creation of a load-bearing mandibular defect. Two bioreactor geometries were tested: a larger complex bioreactor with a central groove, and a smaller rectangular bioreactor that were filled with a mix of xenograft and autograft (initial bone volume/total volume BV/TV of 31.8 ± 1.6%). At transfer, the tissues generated within large and small bioreactors were composed of a mix of lamellar and woven bone and had BV/TV of 55.3 ± 2.6% and 59.2 ± 6.3%, respectively. After transfer of the large bioreactors to the mandibular defect, the bioreactor tissues continued to remodel, reaching a final BV/TV of 64.5 ± 6.2%. Despite recalcitrant infections, viable osteoblasts were seen within the transferred tissues to the mandibular site at the end of the study, suggesting that a vascularized customized bony flap is a potentially effective reconstructive strategy when combined with an optimal stabilization strategy and local antibiotic delivery prior to development of a deep-seated infection.


Assuntos
Osteotomia Mandibular , Procedimentos de Cirurgia Plástica , Humanos , Animais , Ovinos , Engenharia Tecidual , Retalhos Cirúrgicos/cirurgia , Mandíbula/cirurgia , Transplante Ósseo
6.
Proc Natl Acad Sci U S A ; 119(49): e2209531119, 2022 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-36454751

RESUMO

The molecular mechanisms underlying the stability of mature neurons and neural circuits are poorly understood. Here we explore this problem and discover that the Hox genes are a component of the genetic program that maintains normal neural function in adult Drosophila. We show that post-developmental downregulation of the Hox gene Ultrabithorax (Ubx) in adult neurons leads to substantial anomalies in flight. Mapping the cellular basis of these effects reveals that Ubx is required within a subset of dopaminergic neurons, and cell circuitry analyses in combination with optogenetics allow us to link these dopaminergic neurons to flight control. Functional imaging experiments show that Ubx is necessary for normal dopaminergic activity, and neuron-specific RNA-sequencing defines two previously uncharacterized ion channel-encoding genes as potential mediators of Ubx behavioral roles. Our study thus reveals a novel role of the Hox system in controlling adult behavior and neural function. Based on the broad evolutionary conservation of the Hox system across distantly related animal phyla, we predict that the Hox genes might play neurophysiological roles in adult forms of other species, including humans.


Assuntos
Proteínas de Drosophila , Genes Homeobox , Animais , Evolução Biológica , Neurônios Dopaminérgicos , Drosophila/genética , Proteínas de Drosophila/genética , Genes Homeobox/genética , Proteínas de Homeodomínio/genética , Optogenética , Fatores de Transcrição/genética
7.
Int J Mycobacteriol ; 11(1): 116-119, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35295034

RESUMO

Drug-resistant tuberculosis (DR-TB) is a serious public health of concern. We present the management of multidrug-resistant (MDR)-TB with skin reaction in Zanzibar in a patient who had prior exposure to anti-TB drugs. The reaction developed 4 months later, following MDR-TB treatment, stopped when the drug was withdrawn, and reappeared when reintroduced. Close monitoring is important in managing DR-TB cases, and an active DR-TB safety, monitoring, and management is required to detect, monitor, and manage adverse events timely.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Antituberculosos/efeitos adversos , Clofazimina/efeitos adversos , Humanos , Tanzânia , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico
8.
Front Robot AI ; 8: 650885, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34790702

RESUMO

Autonomy is becoming increasingly important for the robotic exploration of unpredictable environments. One such example is the approach, proximity operation, and surface exploration of small bodies. In this article, we present an overview of an estimation framework to approach and land on small bodies as a key functional capability for an autonomous small-body explorer. We use a multi-phase perception/estimation pipeline with interconnected and overlapping measurements and algorithms to characterize and reach the body, from millions of kilometers down to its surface. We consider a notional spacecraft design that operates across all phases from approach to landing and to maneuvering on the surface of the microgravity body. This SmallSat design makes accommodations to simplify autonomous surface operations. The estimation pipeline combines state-of-the-art techniques with new approaches to estimating the target's unknown properties across all phases. Centroid and light-curve algorithms estimate the body-spacecraft relative trajectory and rotation, respectively, using a priori knowledge of the initial relative orbit. A new shape-from-silhouette algorithm estimates the pole (i.e., rotation axis) and the initial visual hull that seeds subsequent feature tracking as the body gets more resolved in the narrow field-of-view imager. Feature tracking refines the pole orientation and shape of the body for estimating initial gravity to enable safe close approach. A coarse-shape reconstruction algorithm is used to identify initial landable regions whose hazardous nature would subsequently be assessed by dense 3D reconstruction. Slope stability, thermal, occlusion, and terra-mechanical hazards would be assessed on densely reconstructed regions and continually refined prior to landing. We simulated a mission scenario for approaching a hypothetical small body whose motion and shape were unknown a priori, starting from thousands of kilometers down to 20 km. Results indicate the feasibility of recovering the relative body motion and shape solely relying on onboard measurements and estimates with their associated uncertainties and without human input. Current work continues to mature and characterize the algorithms for the last phases of the estimation framework to land on the surface.

9.
J Neurosci ; 41(40): 8297-8308, 2021 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-34417328

RESUMO

All what we see, touch, hear, taste, or smell must first be detected by the sensory elements of our nervous system. Sensory neurons, therefore, represent a critical component in all neural circuits and their correct function is essential for the generation of behavior and adaptation to the environment. Here, we report that the evolutionarily-conserved microRNA (miRNA) miR-263b plays a key behavioral role in Drosophila melanogaster through effects on the function of larval sensory neurons. Several independent experiments (in 50:50 male:female populations) support this finding: first, miRNA expression analysis, via reporter expression and fluorescent-activated cell sorting (FACS)-quantitative PCR (qPCR) analysis, demonstrate miR-263b expression in larval sensory neurons. Second, behavioral tests in miR-263b null mutants show defects in self-righting, an innate and evolutionarily conserved posture-control behavior that allows larvae to rectify their position if turned upside-down. Third, competitive inhibition of miR-263b in sensory neurons using a miR-263b "sponge" leads to self-righting defects. Fourth, systematic analysis of sensory neurons in miR-263b mutants shows no detectable morphologic defects in their stereotypic pattern, while genetically-encoded calcium sensors expressed in the sensory domain reveal a reduction in neural activity in miR-263b mutants. Fifth, miR-263b null mutants show reduced "touch-response" behavior and a compromised response to sound, both characteristic of larval sensory deficits. Furthermore, bioinformatic miRNA target analysis, gene expression assays, and behavioral phenocopy experiments suggest that miR-263b might exert its effects, at least in part, through repression of the basic helix-loop-helix (bHLH) transcription factor Atonal Altogether, our study suggests a model in which miRNA-dependent control of transcription factor expression affects sensory function and behavior.SIGNIFICANCE STATEMENT Sensory neurons are key to neural circuit function, but how these neurons acquire their specific properties is not well understood. Here, we examine this problem, focusing on the roles played by microRNAs (miRNAs). Using Drosophila, we demonstrate that the evolutionarily-conserved miRNA miR-263b controls sensory neuron function allowing the animal to perform an adaptive, elaborate three-dimensional movement. Our work thus shows that microRNAs can control complex motor behaviors by modulating sensory neuron physiology, and suggests that similar miRNA-dependent mechanisms may operate in other species. The work contributes to advance the understanding of the molecular basis of behavior and the biological roles of microRNAs within the nervous system.


Assuntos
MicroRNAs/biossíntese , Movimento/fisiologia , Postura/fisiologia , Reflexo de Endireitamento/fisiologia , Células Receptoras Sensoriais/fisiologia , Animais , Drosophila melanogaster , Feminino , Masculino , MicroRNAs/genética
10.
Pediatrics ; 147(6)2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34021063

RESUMO

BACKGROUND AND OBJECTIVES: Use of mid-upper arm circumference (MUAC) as a single screening tool for severe acute malnutrition (SAM) assumes that children with a low weight-for-height z score (WHZ) and normal MUAC have lower risks of morbidity and mortality. However, the pathophysiology and functional severity associated with different anthropometric phenotypes of SAM have never been well characterized. We compared clinical characteristics, biochemical features, and health and nutrition histories of nonedematous children with SAM who had (1) low WHZ only, (2) both low WHZ and low MUAC, or (3) low MUAC only. METHODS: In Bangladesh, Burkina Faso, and Liberia, we conducted a multicentric cohort study in uncomplicated, nonedematous children with SAM and low MUAC only (n = 161), low WHZ only (n = 138), or a combination of low MUAC and low WHZ (n = 152). Alongside routine anthropometric measurements, we collected a wide range of critical indicators of clinical and nutritional status and viability; these included serum leptin, an adipocytokine negatively associated with mortality risk in SAM. RESULTS: Median leptin levels at diagnosis were lower in children with low WHZ only (215.8 pg/mL; P < .001) and in those with combined WHZ and MUAC deficits (180.1 pg/mL; P < .001) than in children with low MUAC only (331.50 pg/mL). The same pattern emerged on a wide range of clinical indicators, including signs of severe wasting, dehydration, serum ferritin levels, and caretaker-reported health deterioration, and was replicated across study sites. CONCLUSIONS: Illustrative of the likely heterogeneous functional severity of the different anthropometric phenotypes of SAM, our results confirm the need to retain low WHZ as an independent diagnostic criterion.


Assuntos
Desnutrição Aguda Grave/diagnóstico , Biomarcadores/sangue , Pesos e Medidas Corporais , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Lactente , Masculino , Medição de Risco , Desnutrição Aguda Grave/sangue
11.
J Neurogenet ; 34(3-4): 527-548, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32772603

RESUMO

Since Caenorhabditis elegans was first introduced as a genetic model organism by Sydney Brenner, researchers studying it have made significant contributions in numerous fields including investigations of the pathophysiology of neurodegenerative diseases. The simple anatomy, optical transparency, and short life-span of this small nematode together with the development and curation of many openly shared resources (including the entire genome, cell lineage and the neural map of the animal) allow researchers using C. elegans to move their research forward rapidly in an immensely collaborative community. These resources have allowed researchers to use C. elegans to study the cellular processes that may underlie human diseases. Indeed, many disease-associated genes have orthologs in C. elegans, allowing the effects of mutations in these genes to be studied in relevant and reproducible neuronal cell-types at single-cell resolution in vivo. Here we review studies that have attempted to establish genetic models of specific human neurodegenerative diseases (ALS, Alzheimer's Disease, Parkinson's Disease, Huntington's Disease) in C. elegans and what they have contributed to understanding the molecular and genetic underpinnings of each disease. With continuous advances in genome engineering, research conducted using this small organism first established by Brenner, Sulston and their contemporaries will continue to contribute to the understanding of human nervous diseases.


Assuntos
Caenorhabditis elegans/genética , Modelos Animais de Doenças , Doenças Neurodegenerativas/genética , Animais , Animais Geneticamente Modificados , Apoptose , Sistemas CRISPR-Cas , Caenorhabditis elegans/fisiologia , Proteínas de Caenorhabditis elegans/metabolismo , Genes de Helmintos , Humanos , Mitocôndrias/metabolismo , Modelos Neurológicos , Proteínas do Tecido Nervoso/fisiologia , Neurotransmissores/fisiologia , Proteostase
12.
Biomaterials ; 256: 120185, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32599360

RESUMO

Mandibular reconstruction requires functional and aesthetic repair and is further complicated by contamination from oral and skin flora. Antibiotic-releasing porous space maintainers have been developed for the local release of vancomycin and to promote soft tissue attachment. In this study, mandibular defects in six sheep were inoculated with 106 colony forming units of Staphylococcus aureus; three sheep were implanted with unloaded porous space maintainers and three sheep were implanted with vancomycin-loaded space maintainers within the defect site. During the same surgery, 3D-printed in vivo bioreactors containing autograft or xenograft were implanted adjacent to rib periosteum. After 9 weeks, animals were euthanized, and tissues were analyzed. Antibiotic-loaded space maintainers were able to prevent dehiscence of soft tissue overlying the space maintainer, reduce local inflammatory cells, eliminate the persistence of pathogens, and prevent the increase in mandibular size compared to unloaded space maintainers in this sheep model. Animals with an untreated mandibular infection formed bony tissues with greater density and maturity within the distal bioreactors. Additionally, tissues grown in autograft-filled bioreactors had higher compressive moduli and higher maximum screw pull-out forces than xenograft-filled bioreactors. In summary, we demonstrated that antibiotic-releasing space maintainers are an innovative approach to preserve a robust soft tissue pocket while clearing infection, and that local infections can increase local and remote bone growth.


Assuntos
Mandíbula , Reconstrução Mandibular , Animais , Antibacterianos/uso terapêutico , Reatores Biológicos , Porosidade , Próteses e Implantes , Ovinos
13.
Med Hypotheses ; 144: 109925, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32544740

RESUMO

In the present study, we used the potential of bioinformatics and computational analysis to predict the existence and biological relevance of zinc finger (ZF) motifs in heamagglutinin (HA) protein of Avian Influenza (AI) virus. Sequence data of Avian Influenza (AI) viruses were retrieved from accessible databases (GenBank, GISAID, IRD) and analyzed for the existence, as well as functional prediction of the putative zinc finger or ''zinc-binding'' motif(s) of HA protein. It is hypothesized that the ZF motif(s) in HA of AI virus can be used as a ''novel'' biomarker for categorization of the virus and/or its virulence. As a model for analysis, we used the H5 subtypes of highly pathogenic, non-pathogenic and low pathogenic avian influenza (HPAI, NPAI and LPAI) viruses of H5N1 and H5N2 of avian and human origins. Interestingly, our method of characterization using the zinc-finger agrees with the existing classification in distinguishing between highly pathogenic and non-pathogenic or low pathogenic subtypes. The new method also clearly distinguished between low and non-pathogenic strains of H5N2 and H5N1 which are indistinguishable by the existing method that utilizes the sequence of the polybasic amino acids of the proteolytic cleavage site for pathogenicity. It is hypothesized that zinc through the activities of zinc-binding proteins modulates the virulence property of the viral subtypes. Our observation further revealed that only the HA protein among the eight encoded proteins of influenza viruses contain high numbers of Cys-His residues. It is expected that the information gathered from the analysis of the data will be useful to generate more research hypotheses/designs that will give further insight towards the identification and control of avian influenza virus through the molecular manipulation of zinc finger motifs present in viral HA protein.


Assuntos
Virus da Influenza A Subtipo H5N1 , Vírus da Influenza A Subtipo H5N2 , Influenza Aviária , Animais , Galinhas , Hemaglutininas , Humanos , Virulência , Zinco
14.
J Appl Clin Med Phys ; 21(7): 173-180, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32573916

RESUMO

BACKGROUND: Radiation effective dose to the red bone-marrow, a critical organ in the therapy of differentiated thyroid carcinoma (DTC) with radioiodine-131 (131 I), cannot be measured directly. As radioiodine concentration is comparable in blood and most organs, and is believed to be similar in red marrow, the effective dose to the blood seems to be a good first-order approximation of the radiation effective dose to the hematopoietic system and a better means to quantifying exposure from therapy compared to the total amount of activity administered. PURPOSE: We applied four formulas (Lassmann et al (standard) [2008], Eur J Nucl Med Molecul Imaging, 35:1405-1412), (Thomas et al. [1993], Nucl Med Biol, 20:157-162), (Sisson et al. [2003], J Nucl Med, 44:898-903; Ha¨nscheid et al. [2009], Endocr Relat Cancer, 16:1283-1289) and (Ha¨nscheid et al. [2006], J Nucl Med, 47:648-654) and compared between the estimated values of the effective dose that were obtained by three formulas and those obtained by the standard one. MATERIALS AND METHODS: Twenty-seven patients, 22 women and 5 men, suffering from DTC were enrolled in this study. Whole-body probe measurements and blood collections (2 mL whole-blood samples) were conducted at 2, 6, 24, 48, 72-96 h after the administration of 131 I to obtain time-activity curves. Whole-body measurements were performed as conjugate view (anterior and posterior) counts by scintillation camera imaging. RESULTS: By comparing the values of blood effective dose that were obtained by applying Thomas et al. [1993], Nucl Med Biol, 20:157-162; Sisson et al. [2003], J Nucl Med, 44:898-903 and Ha¨nscheid et al. [2009], Endocr Relat Cancer, 16:1283-1289, and Ha¨nscheid et al. [2006], J Nucl Med, 47:648-654, techniques, with those obtained by (Lassmann et al (standard technique) [2008], Eur J Nucl Med Molecul Imaging, 35:1405-1412), we found that these values are, respectively, 15.0%, 40.0%, and 41.0% more than those obtained by using the standard method. To our knowledge no papers have been published previously that compare between these dosimetric approaches. CONCLUSION: Highly overestimated or highly underestimated results obtained by a certain method or technique, compared with those obtained by the standard method, are not desirable, they tend to exaggerate in applying radiation protection procedures, by increasing or decreasing, which, in both cases, become far from the realistic or recommended procedures. As an operating philosophy, the objective of radiation safety practices simply should not be to keep radiation doses within legal limits or maximum permissible doses (MPDs ), but to keep them "as low as reasonably achievable" (ALARA concept). MPDs should not be considered as thresholds below which exposure to radiation is of no concern, they are not assumed to be totally risk free, and any reasonable technique for reducing radiation dose may have potential benefits in the long run.


Assuntos
Radioisótopos do Iodo , Neoplasias da Glândula Tireoide , Medula Óssea , Feminino , Humanos , Radioisótopos do Iodo/uso terapêutico , Masculino , Radiometria , Neoplasias da Glândula Tireoide/radioterapia , Neoplasias da Glândula Tireoide/cirurgia
15.
Biochem Biophys Res Commun ; 528(4): 698-705, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32517868

RESUMO

Zinc transporters of the ZIP (Slc39, importers) and ZnT (Slc30, exporters) protein families have evolutionary conserved roles in biology. The aim of the present study was to explore the role of zinc, and zinc transporters Zip10 and Znt1a in zebrafish hatching gland development and larval hatching. In the study, knockdown of genes for Zip10 and Znt1a in zebrafish embryos was achieved using morpholino-modified oligonucleotides. A partial loss-of-function Znt1a mutant (Znt1asa17) allowed comparison with the Znt1a morphant. Free Zn2+ in embryos and apoptosis were investigated using fluorescent dyes whereas gene expression was investigated by whole-mount in situ hybridization (WISH). The results showed high levels of free Zn2+ in the hatching gland cells (HGC) along with abundant expression of zip10 and znt1a in normal embryo. Knockdown of zip10 reduced free Zn2+ in HGC, ceased their normal developmental apoptosis, and resulted in displacement and later disappearance of hatching glands and hatching enzymes he1a and catL1b, and inability to hatch. Conversely, knockdown of znt1a or the Znt1asa17 mutation accelerated hatching and coincided with high expression of hatching enzymes and free Zn2+ in the HGC. Thus, Zip10 and free Zn2+ in the HGC are required both for their development and function. This study also demonstrated the opposite functions of the two zinc transporters, ZIP10 and ZnT1 as well as shedding light on the role of Zn2+ in regulation of the human hatching enzyme homologue, ovastacin, which is activated by zinc and cleaves the zona pellucida protein, ZP2, to prevent polyspermy.


Assuntos
Peixe-Zebra/embriologia , Zinco/metabolismo , Animais , Regulação da Expressão Gênica no Desenvolvimento , Mutação com Perda de Função , Regulação para Cima , Peixe-Zebra/genética , Peixe-Zebra/metabolismo
16.
J Trace Elem Med Biol ; 60: 126496, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32199393

RESUMO

BACKGROUND: Zinc is one of the vital micronutrients required through various developmental stages in animals. Zinc transporter-1 (ZnT1; Slc30a1) is essential in vertebrates for nutritional zinc uptake and cellular zinc extrusion. Knockout of ZnT1 is lethal in vertebrates and there are therefore few functional studies of this protein in vivo. METHODS: In the present study we characterised the embryonic development in a zebrafish Znt1a mutant (Znt1asa17) which is lacking the last 40 amino acids of Znt1a as generated by TILLING. In parallel experiments, we compared the development of a zebrafish embryo Znt1a morphant (Znt1aMO) which was generated by knockdown of Znt1a using morpholino-modified oligonucliotides. RESULTS: The homozygous Znt1asa17 embryo is viable, but displays a subtle phenotype informing on the biological roles of Znt1a. The Znt1asa17 fish have delayed development, including attenuated epiboly. They further show a decrease in phosphorylated extracellular signal-regulated kinases 1 and 2 (pERK1/2), retarded yolk resorption, and impaired clearance of free Zn2+ from the vitelline fluid and its storage in hatching gland cells. All these aberrations are milder versions of those observed upon knockdown of Znt1a by morpholinos. Interestingly, the phenotype could be rescued by addition of the cell-permeable zinc chelator, N,N,N',N'-tetrakis(2-pyridinylmethyl)-1,2-ethanediamine (TPEN) to the incubation medium and was aggravated by addition of zinc(II). Thus, the Znt1asa17 mutant has a reduced ability to handle zinc and can be characterised as a hypomorph. CONCLUSION: This study is the first to show that the last 40 amino acids of Znt1a are of importance for its role in zinc homeostasis and ability to activate the MAPK/ERK pathway contrary to what was previously thought.


Assuntos
Proteínas de Transporte/genética , Desenvolvimento Embrionário/genética , Proteínas de Peixe-Zebra/genética , Aminoácidos/genética , Aminoácidos/metabolismo , Animais , Proteínas de Transporte/metabolismo , Homeostase/genética , Mutação , Peixe-Zebra , Proteínas de Peixe-Zebra/metabolismo , Zinco/metabolismo
17.
Trop Anim Health Prod ; 52(3): 1249-1255, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32006232

RESUMO

Graded concentrations (200, 400 and 800 mg/kg) of the aqueous stem bark extract of Khaya senegalensis was evaluated for its therapeutic efficacy against experimentally induced coccidiosis in broiler chicken. The phytochemical analysis shows the presence of tannins, saponins, cardiac glycosides and steroids. There was significant reduction in oocyst count across the groups in a graded dose manner with 800 mg/kg being the most efficacious dose. There was also weight gain across the treatment groups with immuno-modulatory and erythropoetic activities observed. Also, a significant (p < 0.05) graded dose-dependent reduction in the oocyst count in the treatment groups. A significant (p < 0.05) increase in mean weight gain was also recorded across the experimental groups except the negative control. The haematology also showed a dose-dependent increase in red blood cells, haemoglobin and packed cell volume of the treatment groups. The extract had no significant difference (p > 0.05) on the white blood cells, but a slight decrease in the white blood cells and heterophil counts was observed at 400 mg/kg. Furthermore, the aspartate amino transaminase level showed a significant difference (p < 0.05). Fluctuating levels of other serum biochemical parameters such as total protein, albumin and potassium were observed. No significant difference (p > 0.05) in the sodium concentration was observed. In addition, oxidative stress biomarkers such as catalase significantly increased (p < 0.05) in all the experimental groups in addition to the concomitant increase in reduced gluthathione (GSH) and superoxide dismutase (SOD) levels. Conclusively, the aqueous extract of K. senegalensis was effective in the management of coccidiosis thus supporting its folkloric use.


Assuntos
Galinhas , Coccidiose/veterinária , Coccidiostáticos/farmacologia , Eimeria/efeitos dos fármacos , Meliaceae/química , Extratos Vegetais/uso terapêutico , Animais , Coccidiose/tratamento farmacológico , Coccidiostáticos/química , Oocistos/efeitos dos fármacos , Fitoterapia , Casca de Planta/química , Extratos Vegetais/química , Doenças das Aves Domésticas/tratamento farmacológico , Aumento de Peso/efeitos dos fármacos
18.
Curr Biol ; 29(16): 2665-2675.e4, 2019 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-31327720

RESUMO

Movement is the main output of the nervous system. It emerges during development to become a highly coordinated physiological process essential to survival and adaptation of the organism to the environment. Similar movements can be observed in morphologically distinct developmental stages of an organism, but it is currently unclear whether or not these movements have a common molecular cellular basis. Here we explore this problem in Drosophila, focusing on the roles played by the microRNA (miRNA) locus miR-iab4/8, which we previously showed to be essential for the normal corrective response displayed by the fruit fly larva when turned upside down (self-righting). Our study shows that miR-iab4 is required for normal self-righting across all three Drosophila larval stages. Unexpectedly, we also discover that this miRNA is essential for normal self-righting behavior in the adult fly, an organism with different morphology, neural constitution, and biomechanics. Through the combination of gene expression, optical imaging, and quantitative behavioral approaches, we provide evidence that miR-iab4 exerts its effects on adult self-righting behavior in part through repression of the Hox gene Ultrabithorax (Ubx) in a specific set of adult motor neurons, the NB2-3/lin15 neurons. Our results show that miRNA controls the function, rather than the morphology, of these neurons and demonstrate that post-developmental changes in Hox gene expression can modulate behavior in the adult. Our work reveals that a common miRNA-Hox genetic module can be re-deployed in different neurons to control functionally equivalent movements in biomechanically distinct organisms and describes a novel post-developmental role of the Hox genes in adult neural function.


Assuntos
Proteínas de Drosophila/genética , Drosophila melanogaster/fisiologia , Proteínas de Homeodomínio/genética , MicroRNAs/genética , Fatores de Transcrição/genética , Animais , Fenômenos Biomecânicos , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/crescimento & desenvolvimento , Redes Reguladoras de Genes/genética , Genes Homeobox/fisiologia , Proteínas de Homeodomínio/metabolismo , Larva/fisiologia , MicroRNAs/metabolismo , Movimento/fisiologia , Fatores de Transcrição/metabolismo
19.
J Oral Maxillofac Surg ; 77(9): 1867.e1-1867.e8, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31228425

RESUMO

Iatrogenic cervicofacial subcutaneous emphysema is a well-reported entity in the field of dentistry and oral and maxillofacial surgery, especially with the use of air-driven headpieces. Cervicofacial subcutaneous emphysema sequelae after maxillofacial trauma, however, has been reported less and the self-induced variant is even rarer. We report a case of massive cervicofacial subcutaneous emphysema, pneumomediastinum, and pneumopericardium in a healthy 16-year-old boy after blunt trauma to the face, which caused a nondisplaced anterior maxillary wall fracture. The findings from the present case report will validate the common phrase "no nose blowing or holding your sneezes" that clinicians tell patients after maxillofacial trauma and sinus surgery.


Assuntos
Enfisema Mediastínico , Pneumopericárdio , Enfisema Subcutâneo , Ferimentos não Penetrantes , Adolescente , Progressão da Doença , Face , Humanos , Masculino , Enfisema Mediastínico/etiologia , Pneumopericárdio/etiologia , Enfisema Subcutâneo/etiologia , Ferimentos não Penetrantes/complicações
20.
Radiat Oncol J ; 37(1): 60-65, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30947482

RESUMO

PURPOSE: The quality assurance (QA) chart rounds are multidisciplinary meetings to review radiation therapy (RT) treatment plans. This study focus on describing the changes in RT management based on QA round reviews in a single institution. MATERIALS AND METHODS: After 9 full years of implementation, a retrospective review of all patients whose charts passed through departmental QA chart rounds from 2007 to 2015. The reviewed cases were presented for RT plan review; subcategorized based on decision in QA rounds into: approved, minor modifications or major modifications. Major modification defined as any substantial change which required patient re-simulation or re-planning prior to commencement of RT. Minor modification included treatment plan changes which didn't necessarily require RT re-planning. RESULTS: Overall 7,149 RT treatment plans for different anatomical sites were reviewed at QA rounds. From these treatment plans, 6,654 (93%) were approved, 144 (2%) required minor modifications, while 351 (5%) required major modifications. Major modification included changes in: selected RT dose (96/351, 27%), target volume definition (127/351, 36%), organs-at-risk contouring (10/351, 3%), dose volume objectives/constraints criteria (90/351, 26%), and intent of treatment (28/351, 8%). The RT plans which required major modification according to the tumor subtype were as follows: head and neck (104/904, 12%), thoracic (12/199, 6%), gastrointestinal (33/687,5%), skin (5/106, 5%), genitourinary (16/359, 4%), breast (104/2387, 4%), central nervous system (36/846, 4%), sarcoma (11/277, 4%), pediatric (7/251, 3%), lymphoma (10/423, 2%), gynecological tumors (2/359, 1%), and others (11/351, 3%). CONCLUSION: Multi-disciplinary standardized QA chart rounds provide a comprehensive and an influential method on RT plans and/ or treatment decisions.

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