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1.
J Stomatol Oral Maxillofac Surg ; 125(3S): 101845, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38575496

RESUMO

PURPOSE: The aim of this study is to compare the outcomes of vascular anastomosis using loupes magnification versus operative microscope magnification in reconstructive surgery. METHODS: We performed a systematic review of MEDLINE (via PubMed), Scopus and Cochrane Library database according to the PRISMA guidelines. Comparative studies between the two techniques and single arm studies reporting on loupes reconstruction were included. Random-effects model meta-analyses were performed. RESULTS: Twelve studies, reporting a total of 3908 of flaps, 3409 of which were performed under loupes magnification and 499 under the operative microscope magnification were selected for analysis. No statistically significant differences were observed regarding total flap loss and vascular complication between the two arms. In the Loupes group the rate of total flap loss was 2.65% (95% CI: 1.15-4.63) and the rate of vascular complications 4.49% (95% CI: 2.58-6.84). CONCLUSION: Loupes magnification under circumstances can provide a safe and effective alternative to microvascular reconstruction in reconstructive surgery. With respect to flap failure and vascular complication rates, there appear to be no statistically significant differences between the anastomoses conducted under Loupes magnification and the standard operative microscope.


Assuntos
Anastomose Cirúrgica , Microscopia , Procedimentos de Cirurgia Plástica , Humanos , Anastomose Cirúrgica/métodos , Anastomose Cirúrgica/instrumentação , Procedimentos de Cirurgia Plástica/métodos , Procedimentos de Cirurgia Plástica/instrumentação , Procedimentos de Cirurgia Plástica/efeitos adversos , Microscopia/métodos , Microscopia/instrumentação , Microcirurgia/métodos , Microcirurgia/instrumentação , Procedimentos Cirúrgicos Vasculares/métodos , Procedimentos Cirúrgicos Vasculares/instrumentação , Procedimentos Cirúrgicos Vasculares/efeitos adversos , Retalhos Cirúrgicos
2.
Int J Mol Sci ; 24(20)2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37894831

RESUMO

Observational fear-learning studies in genetically modified animals enable the investigation of the mechanisms underlying the social transmission of fear-related information. Here, we used a three-day protocol to examine fear conditioning by proxy (FCbP) in wild-type mice (C57BL/6J) and mice lacking the ß2-subunit of the nicotinic acetylcholine receptor (nAChR). Male animals of both genotypes were exposed to a previously fear-conditioned (FC) cage mate during the presentation of the conditioned stimulus (CS, tone). On the following day, observer (FCbP) mice were tested for fear reactions to the tone: none of the ß2-KO mice froze to the stimulus, while 30% of the wild-type mice expressed significant freezing. An investigation of the possible factors that predicted the fear response revealed that only wild-type mice that exhibited enhanced and more flexible social interaction with the FC cage mate during tone presentations (Day 2) expressed fear toward the CS (Day-3). Our results indicate that (i) FCbP is possible in mice; (ii) the social transmission of fear depends on the interaction pattern between animals during the FCbP session and (iii) ß2-KO mice display a more rigid interaction pattern compared to wild-type mice and are unable to acquire such information. These data suggest that ß2-nAChRs influence observational fear learning indirectly through their effect on social behaviour.


Assuntos
Receptores Nicotínicos , Camundongos , Masculino , Animais , Receptores Nicotínicos/genética , Camundongos Endogâmicos C57BL , Condicionamento Clássico/fisiologia , Medo/fisiologia , Aprendizagem
3.
Microorganisms ; 11(6)2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37375094

RESUMO

Pseudomonas sp. phDV1 is a polyhydroxyalkanoate (PHA) producer. The presence of the endogenous PHA depolymerase (phaZ) responsible for the degradation of the intracellular PHA is one of the main shortages in the bacterial production of PHA. Further, the production of PHA can be affected by the regulatory protein phaR, which is important in accumulating different PHA-associated proteins. PHA depolymerase phaZ and phaR knockout mutants of Pseudomonas sp. phDV1 were successfully constructed. We investigate the PHA production from 4.25 mM phenol and grape pomace of the mutants and the wild type. The production was screened by fluorescence microscopy, and the PHA production was quantified by HPLC chromatography. The PHA is composed of Polydroxybutyrate (PHB), as confirmed by 1H-nuclear magnetic resonance analysis. The wildtype strain produces approximately 280 µg PHB after 48 h in grape pomace, while the phaZ knockout mutant produces 310 µg PHB after 72 h in the presence of phenol per gram of cells, respectively. The ability of the phaZ mutant to synthesize high levels of PHB in the presence of monocyclic aromatic compounds may open the possibility of reducing the costs of industrial PHB production.

4.
Acta Biomed ; 92(6): e2021430, 2022 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-35075068

RESUMO

Unifocal Langerhans cell histiocytosis (LCH) presents as a solitary focal bone lesion characterized by clonal proliferation of CD1a (+) and langerin(+) dendritic cells, derived from the bone marrow. In 38-69% of cases BRAF-V600E mutation is revealed. It gains attention to maxillofacial surgeons due to involvement of the orofacial region and early onset of jaws symptoms. If overlooked, massive deconstruction of tissues, occurs. We present a case of LCH of the temporomandibular joint in a 14 aged child where fine needle aspiration favorably contributed in an accurate diagnosis combined with the appropriate clinicoradioliogical findings. This can overrule unwarranted biopsy and monitor the treatment largely where aproach to histopathology services is restricted.


Assuntos
Doenças Ósseas , Histiocitose de Células de Langerhans , Idoso , Biópsia por Agulha Fina , Medula Óssea , Histiocitose de Células de Langerhans/diagnóstico , Humanos , Articulação Temporomandibular/diagnóstico por imagem
5.
Neuroscience ; 450: 71-80, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-32750380

RESUMO

Amyotrophic Lateral Sclerosis (ALS) is a neurodegenerative disease that affects upper and lower motor neurons and leads to death a few years after symptom onset. Despite its high morbidity and mortality, its underlying pathogenic mechanisms still remain poorly understood. Although there is increasing evidence for significant changes in the structure and function of synapses on motor neurons, there is a need for a systematic investigation of the role of each synapse subtype in the course of the disease. Here, we focus on large cholinergic synapses on motor neurons, known as C boutons, and investigate their role during ALS progression. We implement a genetic strategy for inactivation of the cholinergic output of C boutons in the SOD1G93A transgenic mouse model of ALS. We demonstrate that although C bouton cholinergic inactivation does not alter mouse survival, it exerts a beneficial effect on motor performance in the rotarod motor task, as evidenced by an increased latency to fall in SOD1G93A mice lacking C bouton cholinergic output. Our results suggest that C bouton cholinergic transmission exerts a negative effect on motor neuron function in ALS, possibly via aberrant excitation, and render C boutons a potential target for future pharmacological intervention.


Assuntos
Esclerose Lateral Amiotrófica , Doenças Neurodegenerativas , Esclerose Lateral Amiotrófica/genética , Animais , Colinérgicos , Modelos Animais de Doenças , Camundongos , Camundongos Transgênicos , Superóxido Dismutase/genética , Superóxido Dismutase-1/genética
6.
Biol Sex Differ ; 8: 21, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28630662

RESUMO

BACKGROUND: Several molecular and cellular processes in the vertebrate brain exhibit differences between males and females, leading to sexual dimorphism in the formation of neural circuits and brain organization. While studies on large-scale brain networks provide ample evidence for both structural and functional sex differences, smaller-scale local networks have remained largely unexplored. In the current study, we investigate sexual dimorphism in cortical dynamics by means of spontaneous Up/Down states, a type of network activity that is exhibited during slow-wave sleep, quiet wakefulness, and anesthesia and is thought to represent the default activity of the cortex. METHODS: Up state activity was monitored by local field potential recordings in coronal brain slices of male and female mice across three ages with distinct secretion profiles of sex hormones: (i) pre-puberty (17-21 days old), (ii) 3-9 adult (months old), and (iii) old (19-24 months old). RESULTS: Female mice of all ages exhibited longer and more frequent Up states compared to aged-matched male mice. Power spectrum analysis revealed sex differences in the relative power of Up state events, with female mice showing reduced power in the delta range (1-4 Hz) and increased power in the theta range (4-8 Hz) compared to male mice. No sex differences were found in the characteristics of Up state peak voltage and latency. CONCLUSIONS: The present study revealed for the first time sex differences in intracortical network activity, using an ex vivo paradigm of spontaneously occurring Up/Down states. We report significant sex differences in Up state properties that are already present in pre-puberty animals and are maintained through adulthood and old age.


Assuntos
Córtex Cerebral/fisiologia , Caracteres Sexuais , Animais , Córtex Cerebral/crescimento & desenvolvimento , Feminino , Masculino , Camundongos Endogâmicos C57BL
7.
Front Aging Neurosci ; 8: 91, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27199738

RESUMO

In order to address pathological cognitive decline effectively, it is critical to adopt early preventive measures in individuals considered at risk. It is therefore essential to develop approaches that identify such individuals before the onset of irreversible dementia. A deficient cholinergic system has been consistently implicated as one of the main factors associated with a heightened vulnerability to the aging process. In the present study we used mice lacking high affinity nicotinic receptors (ß2-/-), which have been proposed as an animal model of accelerated/premature cognitive aging. Our aim was to identify behavioral signs that could serve as indicators or predictors of impending cognitive decline. We used test batteries in order to assess cognitive functions and additional tasks to investigate spontaneous behaviors, such as species-specific activities and exploration/locomotion in a novel environment. Our data confirm the hypothesis that ß2-/- animals exhibit age-related cognitive impairments in spatial learning. In addition, they document age-related deficits in other areas, such as recognition memory, burrowing and nesting building, thereby extending the validity of this animal model for the study of pathological aging. Finally, our data reveal deficits in spontaneous behavior and habituation processes that precede the onset of cognitive decline and could therefore be useful as a non-invasive behavioral screen for identifying animals at risk. To our knowledge, this is the first study to perform an extensive behavioral assessment of an animal model of premature cognitive aging, and our results suggest that ß2-nAChR dependent cognitive deterioration progressively evolves from initial subtle behavioral changes to global dementia due to the combined effect of the neuropathology and aging.

9.
Cereb Cortex ; 25(8): 2138-48, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24554727

RESUMO

The mechanisms by which aging leads to alterations in brain structure and cognitive deficits are unclear. Α deficient cholinergic system has been implicated as one of the main factors that could confer a heightened vulnerability to the aging process, and mice lacking high-affinity nicotinic receptors (ß2(-/-)) have been proposed as an animal model of accelerated cognitive aging. To date, however, age-related changes in neuronal microanatomy have not been studied in these mice. In the present study, we examine the neuronal structure of yellow fluorescent protein (YFP(+)) layer V neurons in 2 cytoarchitectonically distinct cortical regions in wild-type (WT) and ß2(-/-) animals. We find that (1) substantial morphological differences exist between YFP(+) cells of the anterior cingulate cortex (ACC) and primary visual cortex (V1), in both genotypes; (2) in WT animals, ACC cells are more susceptible to aging compared with cells in V1; and (3) ß2 deletion is associated with a regionally and temporally specific increase in vulnerability to aging. ACC cells exhibit a prematurely aged phenotype already at 4-6 months, whereas V1 cells are spared in adulthood but strongly affected in old animals. Collectively, our data reveal region-specific synergistic effects of aging and genotype and suggest distinct vulnerabilities in V1 and ACC neurons.


Assuntos
Senilidade Prematura/patologia , Córtex Cerebral/patologia , Células Piramidais/patologia , Receptores Nicotínicos/deficiência , Envelhecimento/metabolismo , Envelhecimento/patologia , Senilidade Prematura/metabolismo , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Córtex Cerebral/irrigação sanguínea , Córtex Cerebral/crescimento & desenvolvimento , Córtex Cerebral/metabolismo , Modelos Animais de Doenças , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fenótipo , Células Piramidais/metabolismo , Receptores Nicotínicos/genética
10.
J Craniomaxillofac Surg ; 38(8): 549-53, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20303279

RESUMO

This article presents literary evidence on traumatic cranio-cerebral injuries in ancient Greece from about 900 B.C. to 100 B.C. The main sources of information are epic and classic Greek texts of that period. Homer provides the first literary source of head trauma, which he portrayed in his epic poems The Iliad and The Odyssey. He describes 41 injuries of the head, face and cervical spine, of which all but two were fatal. Subsequently, other classical authors like Plato, Plutarch and others illustrate cases of cranial trauma that occurred mainly in the battlefields, during athletic games or in unusual accidents. They describe some interesting cases of head trauma in prominent men, such as the poet Aeschylos, the kings Pyrrhos and Kyros and Alexander the Great. Most of these descriptions show that the ancient Greeks possessed very good knowledge of the anatomy of the head and neck region and also of the pathophysiological consequences of trauma in the region.


Assuntos
Traumatismos Craniocerebrais/história , Medicina na Literatura , Lesões do Pescoço/história , Grécia Antiga , Mundo Grego/história , Cabeça/anatomia & histologia , História Antiga , Humanos , Pescoço/anatomia & histologia , Poesia como Assunto
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