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71.
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Lara Ahmad Pietro Businaro Simone Regalbuto Matteo Gastaldi Elisabetta Zardini Marta Panzeri Elisa Vegezzi Giuseppe Fiamingo Elena Colombo Sabrina Ravaglia 《Medicine》2022,101(30)
Single reports of Guillain-Barré syndrome (GBS) have been reported worldwide during the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic. While case reports are likely to be biased toward uncommon clinical presentations, systematic assessment of prospective series can highlight the true clinical features and spectrum. In this prospective, observational study, we included all consecutive patients who developed GBS. In patients with SARS-CoV-2 infection as antecedent, the time-gap between the infection and GBS onset had to be ≤30 days. The referral was a neurological University Research Hospital, in the Italian Region more severely involved by the pandemic, and hospitalizing both COVID+ and non-COVID neurological diseases. Clinical, laboratory, cerebrospinal fluid, and electromyographic features of GBS diagnosed between March 2020 and March 2021 were compared to a retrospective series of GBS diagnosed between February 2019 and February 2020 (control population). Nasopharyngeal swab was still positive at GBS onset in 50% of patients. Mild-to-moderate COVID-related pneumonia, as assessed by X-ray (6 patients) or X-ray plus computerized tomography (2 patients) co-occurred in 6 of 10 patients. GBS diagnosed during the pandemic period, including 10 COVID-GBS and 10 non–COVID-GBS, had higher disability on admission (P = .032) compared to the GBS diagnosed between February 2019 and 2020, possibly related to later hospital referral in the pandemic context. Compared to non–COVID-GBS (n = 10) prospectively diagnosed in the same period (March 2020–2021), post–COVID-GBS (n = 10) had a higher disability score on admission (P = .028), lower sum Medical Research Council score (P = .022) and lymphopenia (P = .025), while there were no differences in GBS subtype/variant, severity of peripheral involvement, prognosis and response to treatment. Cerebrospinal fluid search for SARS-CoV-2 RNA and antiganglioside antibodies were negative in all COVID+ patients. Temporal clustering of cases, coinciding with the waves of the pandemic, and concomitant reduction of the incidence of COVID-negative GBSs may indicate a role for SARS-CoV-2 infection in the development of GBS, although the association may simply be related to a bystander effect of systemic inflammation; lack of prevalence of specific GBS subtypes in post–COVID-GBS also support this view. GBS features and prognosis are not substantially different compared to non–COVID-GBS. 相似文献
73.
Lara Schorn Anna Sine Karin Berr Jrg Handschel Rita Depprich Norbert R. Kübler Christoph Sproll Majeed Rana Julian Lommen 《Materials》2022,15(14)
Alloplastic and xenogeneic bone grafting materials are frequently used for bone augmentation. The effect of these materials on precursor cells for bone augmentation is yet to be determined. The aim of this study was to ascertain, in vitro, how augmentation materials influence the growth rates and viability of human unrestricted somatic stem cells. The biocompatibility of two xenogeneic and one alloplastic bone graft was tested using human unrestricted somatic stem cells (USSCs). Proliferation, growth, survival and attachment of unrestricted somatic stem cells were monitored after 24 h, 48 h and 7 days. Furthermore, cell shape and morphology were evaluated by SEM. Scaffolds were assessed for their physical properties by Micro-CT imaging. USSCs showed distinct proliferation on the different carriers. Greatest proliferation was observed on the xenogeneic carriers along with improved viability of the cells. Pore sizes of the scaffolds varied significantly, with the xenogeneic materials providing greater pore sizes than the synthetic inorganic material. Unrestricted somatic stem cells in combination with a bovine collagenous bone block seem to be very compatible. A scaffold’s surface morphology, pore size and bioactive characteristics influence the proliferation, attachment and viability of USSCs. 相似文献
74.
75.
Zhang Xu Jung-Hyun Choi David L. Dai Jun Luo Reese Jalal Ladak Qian Li Yimeng Wang Christine Zhang Shane Wiebe Alex C. H. Liu Xiaozhuo Ran Jiaqi Yang Parisa Naeli Aitor Garzia Lele Zhou Niaz Mahmood Qiyun Deng Mohamed Elaish Rongtuan Lin Lara K. Mahal Tom C. Hobman Jerry Pelletier Tommy Alain Silvia M. Vidal Thomas Duchaine Mohammad T. Mazhab-Jafari Xiaojuan Mao Seyed Mehdi Jafarnejad Nahum Sonenberg 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(32)
76.
Maher Al Khaldi Massine Fellouah Pierre Drolet Julien Ct Bertrand Trilling Alexandre BrindAmour Alexandre Dugas Jean-Franois Tremblay Suzanne Fortin Lara De Guerk Marie-Hlne Auclair Pierre Dub Mikaël Soucisse Lucas Sideris 《Current oncology (Toronto, Ont.)》2022,29(12):9314
Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) is a treatment option for peritoneal metastases (PM) but is associated with significant postoperative morbidity. The aim of this study was to determine the prognostic value of computed tomographic (CT)-measured sarcopenia on postoperative outcomes and survival in patients undergoing CRS-HIPEC for PM from various origins. A retrospective cohort study was conducted between 2012 and 2020. Three-hundred and twelve patients (mean age 57.6 ± 10.3, 34.3% male) were included, of which 88 (28.2%) were sarcopenic. PM from a colorectal origin was the most common in both groups. The proportion of major postoperative complications (Clavien-Dindo ≥ III) was not higher in the sarcopenic group (15.9% in sarcopenic patients vs. 23.2% in nonsarcopenic patients, p = 0.17). The mean Comprehensive Complication Index scores, HIPEC-related toxicities, length of hospital stay, and duration of parenteral nutrition were comparable regardless of sarcopenia status. In the multivariate logistic regression analysis of severe complications, only peritoneal carcinomatosis index reached statistical significance (OR, 1.05; 95% CI, 1.01 to 1.08, p = 0.007). Sarcopenia did not impact origin-specific overall survival on Cox regression analysis. Sarcopenia was not associated with worse rates of postoperative severe complications or worse survival rates. Future prospective studies are required before considering sarcopenia as part of preoperative risk assessment. 相似文献
77.
Michael Rebsamen Christoph Friedli Piotr Radojewski Lara Diem Andrew Chan Roland Wiest Anke Salmen Christian Rummel Robert Hoepner 《CNS Neuroscience & Therapeutics》2023,29(2):538
IntroductionData on structural brain changes after infection with SARS‐CoV‐2 is sparse. We postulate multiple sclerosis as a model to study the effects of SARS‐CoV‐2 on brain atrophy due to the unique availability of longitudinal imaging data in this patient group, enabling assessment of intraindividual brain atrophy rates.MethodsGlobal and regional cortical gray matter volumes were derived from structural MRIs using FreeSurfer. A linear model was fitted to the measures of the matching pre‐SARS‐CoV‐2 images with age as an explanatory variable. The residuals were used to determine whether the post‐SARS‐CoV‐2 volumes differed significantly from the baseline.ResultsFourteen RRMS patients with a total of 113 longitudinal magnetic resonance images were retrospectively analyzed. We found no acceleration of brain atrophy after infection with SARS‐CoV‐2 for global gray matter volume (p = 0.17). However, on the regional level, parahippocampal gyri showed a tendency toward volume reduction (p = 0.0076), suggesting accelerated atrophy during or after infection.ConclusionsOur results illustrate the opportunity of using longitudinal MRIs from existing MS registries to study brain changes associated with SARS‐CoV‐2 infections. We would like to address the global MS community with a call for action to use the available cohorts, reproduce the proposed analysis, and pool the results. 相似文献
78.
Vernica AlfaroLara Rocío MuozHernndez Luis GimnezMiranda Luis BeltrnRomero Francisco Javier CastellMontsalve Pablo Stiefel 《Journal of clinical hypertension (Greenwich, Conn.)》2023,25(1):38
The pancreas fat content has been poorly investigated in essential hypertension. The authors aim to relate pancreas and liver fat content with parameters measuring insulin resistance, beta‐cell function and also with markers of endothelial dysfunction and platelet or endothelial cell destruction. The authors studied a group of 40 male hypertensive patients with well‐controlled blood pressure, maintaining a stable weight, and having not changed their medication during the last year. Pancreas fat content was correlated with HOMA‐IR (r = .616, p < .001), HOMA‐S (r = −.439, p < .005), beta cell function parameter (r = .457, p < .005), and QUICKI (r = .412, p < .01), whereas liver fat was not patients in the highest quartile of pancreas fat content had more circulating endothelial microparticles than patients in the other quartiles (median 129 [94.3–200] vs. 60.9 [49.4–88.8], p = .002). However, patients in the highest quartile of the pancreas fat content distribution did not differ from the lowest in hyperemic response after ischemia nor circulating platelet microparticles count. Liver fat content was not related to any of the parameters studied. In a multivariate stepwise binary logistic regression analysis (Wald Method) circulating endothelial microparticles remain significantly associated with pancreas fat content after adjusting for confounding factors, such as tobacco, diabetes mellitus, hypercholesterolemia, or metabolic syndrome. Our results reflect that in essential hypertension, pancreas fat content is superior to liver fat to study beta‐cell functionality and insulin resistance. Moreover, the authors described for the first time that pancreas fat content is related to endothelial cell destruction. Further studies are needed to confirm this point. 相似文献
79.
Blueberries are rich in polyphenols, and their effect on cardiovascular health, including risk factors for endothelial dysfunction and hypertension, has been investigated in interventional studies. However, the difference between blueberry treatments in varied forms for their cardiovascular-protective effect remains poorly understood. The current study assessed the effects of whole blueberry and freeze-dried blueberry powder compared to a control on cardiovascular health in young adults. A cross-over randomised controlled trial (RCT) was implemented with 1 week of treatment for three treatment groups, each followed by 1 week of wash out period. Systolic (SBP) and diastolic blood pressure (DBP), pulse wave velocity (PWV), plasma cholesterol (low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and total cholesterol) and triglyceride levels (TAG), and glucose and nitrite (NO2-) concentrations were compared following fresh blueberry, freeze-dried blueberry powder, and control treatments. Thirty-seven participants with a mean age of 25.86 ± 6.81 completed the study. No significant difference was observed among fresh blueberry, blueberry powder, and the control arm. Plasma NO2- levels were improved by 68.66% and 4.34% separately following whole blueberry and blueberry powder supplementations compared to the baseline, whereas the control supplementation reported a decrease (−9.10%), although it was not statistically significant. There were no other effects shown for SBP, DBP, total cholesterol, HDL-C, LDL-C, TAG, or glucose. No difference was shown between whole blueberry and freeze-dried blueberry powder consumption for improving cardiovascular health. 相似文献
80.
Ravi Mahalingam Brittany Feia Colin Coleman Kusala Anupindi Pratush Saravanan Amalia Luthens Amalia Bustillos Arpita Das Eileen de Haro Lara Doyle-Meyers Jayme Looper Andrew N. Bubak Christy S. Niemeyer Brent Palmer Maria A. Nagel Vicki Traina-Dorge 《Viruses》2022,14(6)
Primary simian varicella virus (SVV) infection and reactivation in nonhuman primates is a valuable animal model in the study of varicella zoster virus disease [varicella (chickenpox) and herpes zoster (shingles)]. To understand SVV pathogenesis in skin, we inoculated 10 rhesus macaques with SVV, resulting in varicella rash. After the establishment of latency, eight of the monkeys were immunosuppressed using tacrolimus with or without irradiation and prednisone and two monkeys were not immunosuppressed. Zoster rash developed in all immunosuppressed monkeys and in one non-immunosuppressed monkey. Five monkeys had recurrent zoster. During varicella and zoster, SVV DNA in skin scrapings ranged from 50 to 107 copies/100 ng of total DNA and 2–127 copies/100 ng of total DNA, respectively. Detection of SVV DNA in blood during varicella was more frequent and abundant compared to that of zoster. During varicella and zoster, SVV antigens colocalized with neurons expressing β-III tubulin in epidermis, hair follicles, and sweat glands, suggesting axonal transport of the virus. Together, we have demonstrated that both SVV DNA and antigens can be detected in skin lesions during varicella and zoster, providing the basis for further studies on SVV skin pathogenesis, including immune responses and mechanisms of peripheral spread. 相似文献