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1.
BMC Public Health ; 24(1): 871, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38515081

RESUMO

BACKGROUND: The COVID-19 pandemic was characterized by an abundance of information, some of it reliable and some of it misinformation. Evidence-based data on the impact of misinformation on attitudes and behaviours remains limited. Studies indicate that older adults are more likely to embrace and disseminate misinformation than other population groups, making them vulnerable to misinformation. The purpose of this article is to explore the effects of misinformation and information overload on older adults, and to present the management strategies put in place to deal with such effects, in the context of COVID-19. METHODS: A qualitative exploratory approach was adopted to conduct this research. A total of 36 semi-structured interviews were conducted with older adults living in Quebec, Canada. The interviews were fully transcribed and subjected to a thematic content analysis. RESULTS: Participants said they could easily spot misinformation online. Despite this, misinformation and its treatment by the media could generate fear, stress and anxiety. Moreover, the polarization induced by misinformation resulted in tensions and even friendship breakdowns. Participants also denounced the information overload produced largely by the media. To this end, the participants set up information routines targeting the sources of information and the times at which they consulted the information. CONCLUSIONS: This article questions the concept of vulnerability to misinformation by highlighting older adults' agency in managing misinformation and information overload. Furthermore, this study invites us to rethink communication strategies by distinguishing between information overload and misinformation.


Assuntos
COVID-19 , Pandemias , Humanos , Idoso , Comunicação , Pesquisa Qualitativa , Ansiedade , Transtornos de Ansiedade
2.
Explor Res Clin Soc Pharm ; 12: 100379, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38145238

RESUMO

As the COVID-19 pandemic unfolded, community pharmacies adapted rapidly to broaden and adjust the services they were providing to patients, while coping with severe pressure on supply chains and constrained social interactions. This study investigates whether these events had an impact on the medication incidents reported by pharmacists. Results indicate that Canadian pharmacies were able to sustain such stress while maintaining comparable safety levels. At the same time, it appears that some risk factors that were either ignored or not meaningful in the past started to be reported, suggesting that community pharmacists are now aware of a larger set of contributing factors that can lead to medication incidents, notably for medication incidents that can lead to harm.

3.
Front Bioeng Biotechnol ; 11: 1165197, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37324420

RESUMO

Brewer's spent grain (BSG) is an undervalorized organic feedstock residue composed of fermentable macromolecules, such as proteins, starch, and residual soluble carbohydrates. It also contains at least 50% (as dry weight) of lignocellulose. Methane-arrested anaerobic digestion is one of the promising microbial technologies to valorize such complex organic feedstock into value-added metabolic intermediates, such as ethanol, H2, and short-chain carboxylates (SCC). Under specific fermentation conditions, these intermediates can be microbially transformed into medium-chain carboxylates through a chain elongation pathway. Medium-chain carboxylates are of great interest as they can be used as bio-based pesticides, food additives, or components of drug formulations. They can also be easily upgraded by classical organic chemistry into bio-based fuels and chemicals. This study investigates the production potential of medium-chain carboxylates driven by a mixed microbial culture in the presence of BSG as an organic substrate. Because the conversion of complex organic feedstock to medium-chain carboxylates is limited by the electron donor content, we assessed the supplementation of H2 in the headspace to improve the chain elongation yield and increase the production of medium-chain carboxylates. The supply of CO2 as a carbon source was tested as well. The additions of H2 alone, CO2 alone, and both H2 and CO2 were compared. The exogenous supply of H2 alone allowed CO2 produced during acidogenesis to be consumed and nearly doubled the medium-chain carboxylate production yield. The exogenous supply of CO2 alone inhibited the whole fermentation. The supplementation of both H2 and CO2 allowed a second elongation phase when the organic feedstock was exhausted, which increased the medium-chain carboxylate production by 285% compared to the N2 reference condition. Carbon- and electron-equivalent balances, and the stoichiometric ratio of 3 observed for the consumed H2/CO2, suggest an H2- and CO2-driven second elongation phase, converting SCC to medium-chain carboxylates without an organic electron donor. The thermodynamic assessment confirmed the feasibility of such elongation.

4.
J Med Imaging (Bellingham) ; 10(3): 034504, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37274760

RESUMO

Purpose: The adoption of emerging imaging technologies in the medical community is often hampered when they provide a new unfamiliar contrast that requires experience to be interpreted. Dynamic full-field optical coherence tomography (D-FF-OCT) microscopy is such an emerging technique. It provides fast, high-resolution images of excised tissues with a contrast comparable to H&E histology but without any tissue preparation and alteration. Approach: We designed and compared two machine learning approaches to support interpretation of D-FF-OCT images of breast surgical specimens and thus provide tools to facilitate medical adoption. We conducted a pilot study on 51 breast lumpectomy and mastectomy surgical specimens and more than 1000 individual 1.3×1.3 mm2 images and compared with standard H&E histology diagnosis. Results: Using our automatic diagnosis algorithms, we obtained an accuracy above 88% at the image level (1.3×1.3 mm2) and above 96% at the specimen level (above cm2). Conclusions: Altogether, these results demonstrate the high potential of D-FF-OCT coupled to machine learning to provide a rapid, automatic, and accurate histopathology diagnosis with minimal sample alteration.

5.
Phys Rev Lett ; 126(18): 181802, 2021 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-34018798

RESUMO

The CUPID-Mo experiment at the Laboratoire Souterrain de Modane (France) is a demonstrator for CUPID, the next-generation ton-scale bolometric 0νßß experiment. It consists of a 4.2 kg array of 20 enriched Li_{2}^{100}MoO_{4} scintillating bolometers to search for the lepton-number-violating process of 0νßß decay in ^{100}Mo. With more than one year of operation (^{100}Mo exposure of 1.17 kg×yr for physics data), no event in the region of interest and, hence, no evidence for 0νßß is observed. We report a new limit on the half-life of 0νßß decay in ^{100}Mo of T_{1/2}>1.5×10^{24} yr at 90% C.I. The limit corresponds to an effective Majorana neutrino mass ⟨m_{ßß}⟩<(0.31-0.54) eV, dependent on the nuclear matrix element in the light Majorana neutrino exchange interpretation.

6.
Gut ; 70(1): 6-8, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32447309

RESUMO

Full-field optical coherence tomography (FFOCT) is an imaging technique of biological tissue based on tissue light reflectance analysis. We evaluated the feasibility of imaging fresh digestive mucosal biopsies after a quick mounting procedure (5 min) using two distinct modalities of FFOCT. In static FFOCT mode, we gained high-resolution images of general gut tissue-specific architecture, such as oesophageal papillae, gastric pits, duodenal villi and colonic crypts. In dynamic FFOCT mode, we imaged individual epithelial cells of the mucosal lining with a cellular or subcellular resolution and identified cellular components of the lamina propria. FFOCT represents a promising dye-free imaging tool for on-site analysis of gut tissue remodelling.


Assuntos
Trato Gastrointestinal/diagnóstico por imagem , Trato Gastrointestinal/patologia , Tomografia de Coerência Óptica , Biópsia , Endoscopia , Humanos , Mucosa/diagnóstico por imagem , Mucosa/patologia
7.
J Clin Microbiol ; 59(3)2021 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-33303562

RESUMO

As the coronavirus disease 2019 (COVID-19) pandemic second wave is emerging, it is of the upmost importance to screen the population immunity in order to keep track of infected individuals. Consequently, immunoassays for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with high specificity and positive predictive values are needed to obtain an accurate epidemiological picture. As more data accumulate about the immune responses and the kinetics of neutralizing-antibody (nAb) production in SARS-CoV-2-infected individuals, new applications are forecast for serological assays such as nAb activity prediction in convalescent-phase plasma from recovered patients. This multicenter study, involving six hospital centers, determined the baseline clinical performances, reproducibility, and nAb level correlations of 10 commercially available immunoassays. In addition, three lateral-flow chromatography assays were evaluated, as these devices can be used in logistically challenged areas. All assays were evaluated using the same patient panels in duplicate, thus enabling accurate comparison of the tests. Seven immunoassays examined in this study were shown to have excellent specificity (98 to 100%) and good to excellent positive predictive values (82 to 100%) when used in a low (5%)-seroprevalence setting. We observed sensitivities as low as 74% and as high as 95% at ≥15 days after symptom onset. The determination of optimized cutoff values through receiver operating characteristic (ROC) curve analyses had a significant impact on the diagnostic resolution of several enzyme immunoassays by increasing the sensitivity significantly without a large trade-off in specificity. We found that spike-based immunoassays seem to be better correlates of nAb activity. Finally, the results reported here will add to the general knowledge of the interlaboratory reproducibility of clinical performance parameters of immunoassays and provide new evidence about nAb activity prediction.


Assuntos
Anticorpos Neutralizantes/análise , Anticorpos Antivirais/análise , COVID-19/diagnóstico , Ensaios de Triagem em Larga Escala/normas , COVID-19/imunologia , Humanos , Laboratórios , Reprodutibilidade dos Testes , SARS-CoV-2 , Sensibilidade e Especificidade , Estudos Soroepidemiológicos
8.
Rev Med Liege ; 75(S1): 94-100, 2020.
Artigo em Francês | MEDLINE | ID: mdl-33211429

RESUMO

Rising from the province of Wuhan in China, the new coronavirus SARS-CoV-2 broke out in winter 2019, causing a global pandemic. In most cases reported, COVID-19 symptoms include cough, dyspnea, myalgia and asthenia. In some cases, the disease can also cause severe respiratory distress syndrome, requiring intensive care. Recent studies suggest that SARS-CoV-2 infection predisposes to thromboembolic event such as pulmonary embolism. Moreover, there is an overlap between signs and symptoms of pulmonary embolism and COVID-19, which brings a challenge for the diagnosis and could potentially be fatal. Nevertheless, the incidence rate of pulmonary embolism in cases of COVID-19 is currently not known. In this paper we describe six cases of pulmonary embolism associated with COVID-19.


Depuis la fin de l'année 2019, le monde est frappé par une épidémie causée par le virus SARS-CoV-2. La maladie à coronavirus 2019 se manifeste dans la majorité des cas par de la pyrexie, de la toux, de la dyspnée, des myalgies et de la fatigue. Néanmoins, elle peut aussi se présenter sous des formes plus sévères, allant de la pneumopathie hypoxémiante jusqu'à l'insuffisance respiratoire et à la défaillance multiorganique. Des études récentes suggèrent que l'infection à SARS-CoV-2 prédispose aux événements thromboemboliques. Bien que l'incidence de l'embolie pulmonaire dans le cadre de la maladie à coronavirus soit inconnue, elle constitue une complication potentiellement fatale. L'embolie pulmonaire peut être difficile à mettre en évidence car les signes et symptômes peuvent être similaires et se confondre avec ceux d'une pneumopathie à SARS-CoV-2. Nous rapportons 6 cas d'embolie pulmonaire associée à une pneumopathie à SARS-CoV-2.


Assuntos
Infecções por Coronavirus , Pandemias , Pneumonia Viral , Embolia Pulmonar , Betacoronavirus , COVID-19 , China , Humanos , Embolia Pulmonar/diagnóstico , Embolia Pulmonar/etiologia , SARS-CoV-2
9.
Rev Med Liege ; 75(11): 697-698, 2020 Nov.
Artigo em Francês | MEDLINE | ID: mdl-33155440

RESUMO

Coronary aneurysm has an incidence of 1,1 to 4,9 % in patients undergoing a coronary angiography. Many etiologies may be accused, atherosclerosis is associated in up to 50 % of cases. We report the case of a 76-year-old patient with a large coronary aneurysm.


L'anévrisme coronarien a une incidence de 1,1 à 4,9 % chez les patients bénéficiant d'une coronarographie. De nombreuses étiologies peuvent être incriminées, l'athérosclérose y est associée dans 50 % des cas. Nous rapportons ici le cas d'un patient de 76 ans présentant un volumineux anévrisme coronarien.


Assuntos
Aterosclerose , Aneurisma Coronário , Idoso , Aneurisma Coronário/diagnóstico por imagem , Aneurisma Coronário/etiologia , Angiografia Coronária , Humanos
10.
Phys Rev Lett ; 125(14): 141301, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33064531

RESUMO

We present the first Ge-based constraints on sub-MeV/c^{2} dark matter (DM) particles interacting with electrons using a 33.4 g Ge cryogenic detector with a 0.53 electron-hole pair (rms) resolution, operated underground at the Laboratoire Souterrain de Modane. Competitive constraints are set on the DM-electron scattering cross section, as well as on the kinetic mixing parameter of dark photons down to 1 eV/c^{2}. In particular, the most stringent limits are set for dark photon DM in the 6 to 9 eV/c^{2} range. These results demonstrate the high relevance of Ge cryogenic detectors for the search of DM-induced eV-scale electron signals.

11.
Rev Med Liege ; 74(7-8): 375-377, 2019 07.
Artigo em Francês | MEDLINE | ID: mdl-31373448

RESUMO

We report a case of left ventricular pseudo-aneurysm and we take the opportunity to briefly review the literature concerning etiologies, diagnosis and management of this pathology, emphasizing some differences with the true aneurysm.


Nous rapportons un cas de pseudo-anévrysme ventriculaire gauche et nous en profitons pour réaliser une brève revue de la littérature concernant les étiologies, le diagnostic et la prise en charge de cette pathologie, en insistant sur certaines différences avec le vrai anévrysme.


Assuntos
Síndrome Coronariana Aguda , Falso Aneurisma , Aneurisma Cardíaco , Síndrome Coronariana Aguda/complicações , Falso Aneurisma/etiologia , Aneurisma Cardíaco/etiologia , Ventrículos do Coração , Humanos
12.
Brain Struct Funct ; 224(2): 699-711, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30470894

RESUMO

Vestibular dysfunction strongly impairs hippocampus-dependent spatial memory performance and place cell function. However, the hippocampal encoding of vestibular information at the synaptic level, remains sparsely explored and controversial. We investigated changes in in vivo long-term potentiation (LTP) and NMDA glutamate receptor (NMDAr) density and distribution after bilateral vestibular lesions (BVL) in adult rats. At day 30 (D30) post-BVL, the LTP of the population spike recorded in the dentate gyrus (DG) was higher in BVL rats, for the entire 3 h of LTP recording, while no difference was observed in the fEPSP slope. However, there was an increase in EPSP-spike (E-S) potentiation in lesioned rats. NMDArs were upregulated at D7 and D30 predominantly within the DG and CA1. At D30, we observed a higher NMDAr density in the left hippocampus. NMDArs were overexpressed on both neurons and non-neuronal cells, suggesting a decrease of the entorhinal glutamatergic inputs to the hippocampus following BVL. The EPSP-spike (E-S) potentiation increase was consistent with the dorsal hippocampus NMDAr upregulation. Such an increase could reflect a non-specific enhancement of synaptic efficacy, leading to a disruption of memory encoding, and therefore might underlie the memory deficits previously reported in rats and humans following vestibular loss.


Assuntos
Hipocampo/metabolismo , Potenciação de Longa Duração/fisiologia , Receptores de N-Metil-D-Aspartato/metabolismo , Vestíbulo do Labirinto/fisiopatologia , Animais , Potenciais Pós-Sinápticos Excitadores/fisiologia , Masculino , Neurônios/metabolismo , Ratos , Ratos Sprague-Dawley
13.
J Neurosci Methods ; 304: 11-23, 2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-29660368

RESUMO

BACKGROUND: Flow cytometry allows single-cell analysis of peripheral biological samples and is useful in many fields of research and clinical applications, mainly in hematology, immunology, and oncology. In the neurosciences, the flow cytometry separation method was first applied to stem cell extraction from healthy or cerebral tumour tissue and was more recently tested in order to phenotype brain cells, hippocampal neurogenesis, and to detect prion proteins. However, it remains sparsely applied in quantifying membrane receptors in relation to synaptic plasticity. NEW METHOD: We aimed to optimize a flow cytometric procedure for receptor quantification in neurons and non-neurons. A neural dissociation process, myelin separation, fixation, and membrane permeability procedures were optimized to maximize cell survival and analysis in hippocampal tissue obtained from adult rodents. We then aimed to quantify membrane muscarinic acetylcholine receptors (mAChRs) in rats with and without bilateral vestibular loss (BVL). RESULTS: mAChR's were quantified for neuronal and non-neuronal cells in the hippocampus and striatum following BVL. At day 30 but not at day 7 following BVL, there was a significant increase (P ≤ 0.05) in the percentage of neurons expressing M2/4 mAChRs in both the hippocampus and the striatum. CONCLUSION: Here, we showed that flow cytometry appears to be a reliable method of membrane receptor quantification in ex-vivo brain tissue.


Assuntos
Doenças Auditivas Centrais/metabolismo , Citometria de Fluxo/métodos , Hipocampo/citologia , Neuroglia/metabolismo , Neurônios/metabolismo , Receptores Muscarínicos/metabolismo , Animais , Doenças Auditivas Centrais/patologia , Células Cultivadas , Corpo Estriado/patologia , Modelos Animais de Doenças , Masculino , Bainha de Mielina/metabolismo , Neuroglia/patologia , Plasticidade Neuronal/fisiologia , Neurônios/patologia , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Tubulina (Proteína)/metabolismo
14.
Bull Entomol Res ; 107(5): 699-704, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28290255

RESUMO

Leucopis argenticollis (Zetterstedt) and Leucopis piniperda (Malloch) are known to feed on the lineage of Adelges tsugae Annand that is native to western North America, but it is not known if they will survive on the lineage that was introduced from Japan to the eastern USA. In 2014, western Leucopis spp. larvae were brought to the laboratory and placed on A. tsugae collected in either Washington (North American A. tsugae lineage) or Connecticut (Japanese lineage). There were no significant differences in survival or developmental times between flies reared on the two different adelgid lineages. In 2015 and 2016, western Leucopis spp. adults were released at two different densities onto enclosed branches of A. tsugae infested eastern hemlock (Tsuga canadensis (L.) Carr.) in Tennessee and New York. Cages were recovered and their contents examined 4 weeks after release at each location. Leucopis spp. larvae and puparia of the F1 generation were recovered at both release locations and adults of the F1 generation were collected at the Tennessee location. The number of Leucopis spp. offspring collected increased with increasing adelgid density, but did not differ by the number of adult flies released. Flies recovered from cages and flies collected from the source colony were identified as L.argenticollis and L. piniperda using DNA barcoding. These results demonstrate that Leucopis spp. from the Pacific Northwest are capable of feeding and developing to the adult stage on A. tsugae in the eastern USA and they are able to tolerate environmental conditions during late spring and early summer at the southern and northern extent of the area invaded by A. tsugae in the eastern USA.


Assuntos
Dípteros/crescimento & desenvolvimento , Hemípteros , Controle Biológico de Vetores , Comportamento Predatório , Animais , Feminino , Cadeia Alimentar , Masculino , Tsuga , Estados Unidos
15.
Eur Phys J C Part Fields ; 77(11): 785, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-31997932

RESUMO

This paper reports on the development of a technology involving 100 Mo -enriched scintillating bolometers, compatible with the goals of CUPID, a proposed next-generation bolometric experiment to search for neutrinoless double-beta decay. Large mass ( ∼ 1 kg ), high optical quality, radiopure 100 Mo -containing zinc and lithium molybdate crystals have been produced and used to develop high performance single detector modules based on 0.2-0.4 kg scintillating bolometers. In particular, the energy resolution of the lithium molybdate detectors near the Q-value of the double-beta transition of 100 Mo (3034 keV) is 4-6 keV FWHM. The rejection of the α -induced dominant background above 2.6 MeV is better than 8 σ . Less than 10 µ Bq/kg activity of 232 Th ( 228 Th ) and 226 Ra in the crystals is ensured by boule recrystallization. The potential of 100 Mo -enriched scintillating bolometers to perform high sensitivity double-beta decay searches has been demonstrated with only 10 kg × d exposure: the two neutrino double-beta decay half-life of 100 Mo has been measured with the up-to-date highest accuracy as T 1 / 2 = [6.90 ± 0.15(stat.) ± 0.37(syst.)] × 10 18 years . Both crystallization and detector technologies favor lithium molybdate, which has been selected for the ongoing construction of the CUPID-0/Mo demonstrator, containing several kg of 100 Mo .

16.
J Musculoskelet Neuronal Interact ; 16(3): 211-20, 2016 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-27609036

RESUMO

Fusionless devices are currently designed to treat spinal deformities such as scoliosis by the application of a controlled mechanical loading. Growth modulation by dynamic compression was shown to preserve soft tissues. The objective of this in vivo study was to characterize the effect of static vs. dynamic loading on the bone formed during growth modulation. Controlled compression was applied during 15 days on the 7(th) caudal vertebra (Cd7) of rats during growth spurt. The load was sustained in the "static" group and sinusoidally oscillating in the "dynamic" group. The effect of surgery and of the device was investigated using control and sham (operated on but no load applied) groups. A high resolution CT-scan of Cd7 was acquired at days 2, 8 and 15 of compression. Growth rates, histomorphometric parameters and mineral density of the newly formed bone were quantified and compared. Static and dynamic loadings significantly reduced the growth rate by 20% compared to the sham group. Dynamic loading preserved newly formed bone histomorphometry and mineral density whereas static loading induced thicker (+31%) and more mineralized (+12%) trabeculae. A significant sham effect was observed. Growth modulation by dynamic compression constitutes a promising way to develop new treatment for skeletal deformities.


Assuntos
Desenvolvimento Ósseo/fisiologia , Coluna Vertebral/fisiologia , Estresse Mecânico , Animais , Modelos Animais de Doenças , Lâmina de Crescimento/fisiologia , Masculino , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Escoliose/cirurgia , Coluna Vertebral/cirurgia , Microtomografia por Raio-X
17.
Rev Med Liege ; 71(5): 233-5, 2016 May.
Artigo em Francês | MEDLINE | ID: mdl-27337841

RESUMO

We report the case of a patient admitted with upper gastrointestinal bleeding. The CT scan revealed an aorto-duodenal fistula. This case highlights the progression of radiological imaging in parallel with the clinical course. We take this opportunity to write a brief literature review mainly focused on the description and diagnostic modalities of aortoenteric fistulas.


Assuntos
Doenças da Aorta/complicações , Hemorragia Gastrointestinal/etiologia , Fístula Intestinal/complicações , Fístula Vascular/complicações , Idoso , Aorta Abdominal/patologia , Doenças da Aorta/diagnóstico , Doenças da Aorta/cirurgia , Evolução Fatal , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/cirurgia , Humanos , Fístula Intestinal/diagnóstico , Fístula Intestinal/cirurgia , Masculino , Prognóstico , Fístula Vascular/diagnóstico , Fístula Vascular/cirurgia
18.
Hum Reprod ; 31(7): 1493-500, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27165625

RESUMO

STUDY QUESTION: What threshold values of ultrasonographic antral follicle count (AFC) and serum anti-Müllerian hormone (AMH) levels should be considered for ensuring the cryopreservation of sufficient number of in vitro matured (IVM) oocytes, in cancer patients seeking fertility preservation (FP)? SUMMARY ANSWER: AFC and serum AMH values >20 follicles and 3.7 ng/ml, respectively, are required for obtaining at least 10 IVM oocytes for cryopreservation. WHAT IS KNOWN ALREADY: IVM of cumulus oocyte complexes (COCs) followed by oocyte cryopreservation has emerged recently as an option for urgent FP. Recent data have reported that, in healthy patients, 8-20 cryopreserved oocytes after ovarian stimulation would maximize the chance of obtaining a live birth. Although both AFC and AMH have been reported as predictive factors of IVM success in infertile patients with polycystic ovary syndrome (PCOS), there is a dramatic lack of data regarding the values of these parameters in oncological patients as candidates for FP. STUDY DESIGN, SIZE, DURATION: From January 2009 to April 2015, we prospectively studied 340 cancer patients, aged 18-41 years, as candidates for oocyte cryopreservation following IVM. PARTICIPANTS/MATERIALS, SETTING, METHODS: All patients had AFC and AMH measurements, 48-72 h before oocyte retrieval, regardless of the phase of the cycle. COCs were recovered under ultrasound guidance 36 h after hCG priming. Logistic regression allowed the determination of threshold values of AFC and AMH, for obtaining at least 8, 10 or 15 matures oocytes frozen after the IVM procedure. Similar analyses were performed for a final number of mature oocytes ≤2. MAIN RESULTS AND THE ROLE OF CHANCE: Among the 340 cancer patients included, 300 were diagnosed with breast cancers, 14 had hematological malignancies and 26 underwent the procedure for others indications. Overall, the mean age of the population was 31.8 ± 4.5 years. Mean AFC and serum AMH levels were 21.7 ± 13.3 follicles and 4.4 ± 3.8 ng/ml, respectively. IVM was performed in equal proportions during the follicular or luteal phase of the cycle (49 and 51%, respectively). Statistical analysis showed that AFC and AMH values above 28 follicles and 3.9 ng/ml, 20 follicles and 3.7 ng/ml and 19 follicles and 3.5 ng/ml are required, respectively, for obtaining at least 15, 10 or 8 frozen IVM oocytes with a sensitivity ranging from 0.82 to 0.90. On the contrary, ≤2 IVM oocytes were cryopreserved when AFC and AMH were <19 follicles and 3.0 ng/ml, respectively. LIMITATIONS, REASONS FOR CAUTION: Although the potential of cryopreserved IVM oocytes from cancer patients remains unknown, data obtained from infertile PCOS women have shown a dramatically reduced competence of these oocytes when compared with that of oocytes recovered after ovarian stimulation. As a consequence, the optimal number of IVM oocytes frozen in candidates for FP is currently unpredictable. WIDER IMPLICATIONS OF THE FINDINGS: Cryopreservation of oocytes after IVM should be considered in the FP strategy when ovarian stimulation is unfeasible, in particular when markers of the follicular ovarian status are at a relatively high range. Further investigation is needed to objectively assess the real potential of these IVM oocytes after cryopreservation. Therefore, even when a good COCs yield is expected, we should systematically encourage IVM in combination with ovarian tissue cryopreservation. STUDY FUNDING/COMPETING INTERESTS: No external funding was obtained for the present study. The authors have no conflict of interest to declare. TRIAL REGISTRATION NUMBER: Not applicable.


Assuntos
Hormônio Antimülleriano/sangue , Criopreservação/métodos , Técnicas de Maturação in Vitro de Oócitos , Oócitos , Adulto , Feminino , Preservação da Fertilidade , Humanos , Modelos Logísticos , Estudos Prospectivos , Valores de Referência
19.
Gynecol Obstet Fertil ; 44(5): 280-4, 2016 May.
Artigo em Francês | MEDLINE | ID: mdl-26968255

RESUMO

OBJECTIVES: Oocyte vitrification using an open device is thought to be a source of microbiological and chemical contaminations that can be avoided using a closed device. The principal purpose of this study was to compare the two vitrification protocols: closed and open system. The secondary aim was to study the effects of the storage in the vapor phase of nitrogen (VPN) on oocytes vitrified using an open system and to compare it to those of a storage in liquid nitrogen (LN). METHODS: Forty-four patients have been included in our study between November 2014 and May 2015. Two hundred and fourteen oocytes have been vitrified at germinal vesicle (GV), metaphase I (0PB) and metaphase II (1PB) stages. We vitrified 96 oocytes (59 GV/37 0PB) using a closed vitrification device and 118 oocytes (57 GV/31 0PB/30 1PB) using an open device. The vitrified oocytes were then stored either in LN or in VPN. The main outcome measures were the survival rate after warming (SR), meiosis resumption rate (MRR) and maturation rate (MR). RESULTS: The global post-thaw SR was significantly higher for oocytes vitrified using an open system (93.2%) compared to those vitrified using a closed one (64.5%; P<0.001). On the contrary, there was no significant difference in terms of global MRR and MR (82.1% vs. 87.5% and 60.7% vs. 61.2% using closed and open system respectively). The SR, MRR and the MR were not significantly different when vitrified oocytes were stored in VPN or LN (91.6, 83.8, 64.5% vs. 93.9, 89.8, 59.1% respectively). CONCLUSION: Taking into account the limits of our protocol, the open vitrification system remains the more efficient system. The use of sterile liquid nitrogen for oocyte vitrification and the subsequent storage in vapor phase of nitrogen could minimize the hypothetical risks of biological and chemical contaminations.


Assuntos
Criopreservação/instrumentação , Criopreservação/métodos , Oócitos/fisiologia , Adulto , Sobrevivência Celular , Feminino , Temperatura Alta , Humanos , Meiose , Metáfase , Nitrogênio , Estudos Prospectivos
20.
J Gynecol Obstet Biol Reprod (Paris) ; 45(5): 424-44, 2016 May.
Artigo em Francês | MEDLINE | ID: mdl-27021926

RESUMO

Advances on cryopreservation techniques now allow considering oocyte, embryo or ovarian tissue freezing for female fertility preservation. Originally developed for patients suffering from cancer, fertility preservation has rapidly invaded others medical fields, and represents now the standard of care for all young patient diagnosed with a disease that could impair fertility or having to receive possibly gonadotoxic treatment. As a result, autoimmune diseases, some genetic pathologies or iterative pelvic surgeries, at risk of premature ovarian failure, have become common indications of fertility preservation. In addition, the social egg freezing aiming at preventing the age-related fertility decline is still debated in France, although authorized in numerous countries. This review will discuss the different strategies of fertility preservation in young girls and women of reproductive age, regarding different medical or non-medical indications.


Assuntos
Criopreservação , Preservação da Fertilidade/métodos , Oócitos , Ovário , Adolescente , Adulto , Neoplasias da Mama , Criança , Criopreservação/métodos , Embrião de Mamíferos , Feminino , França , Hormônio Liberador de Gonadotropina/análogos & derivados , Humanos , Técnicas de Maturação in Vitro de Oócitos , Infertilidade Feminina/terapia , Neoplasias/tratamento farmacológico , Neoplasias/radioterapia , Insuficiência Ovariana Primária , Adulto Jovem
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