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51.
Chazan B Colodner R Teitler N Chen Y Raz R 《American journal of infection control》2008,36(6):436-438
Health care workers (HCWs) are susceptible to hospital acquired varicella zoster virus (VZV). We evaluated seroprevalence and predictive value of a history of varicella disease (VD) with VZV serology in HCWs in northern Israel. A total of 200 HCWs were enrolled. A high rate of seropositivity for VZV-IgG was found: 98.5% seropositive and only 1.5% seronegative. A positive history of VD was an excellent predictor for the presence of VZV-IgG; however, a negative history of VD does not rule out the presence of VZV-IgG. 相似文献
52.
Ofer Beharier Romina Plitman Mayo Tal Raz Kira Nahum Sacks Letizia Schreiber Yael Suissa-Cohen Rony Chen Rachel Gomez-Tolub Eran Hadar Rinat Gabbay-Benziv Yuval Jaffe Moshkovich Tal Biron-Shental Gil Shechter-Maor Sivan Farladansky-Gershnabel Hen Yitzhak Sela Hedi Benyamini-Raischer Nitzan D. Sela Debra Goldman-Wohl Ziv Shulman Ariel Many Haim Barr Simcha Yagel Michal Neeman Michal Kovo 《The Journal of clinical investigation》2021,131(13)
BACKGROUNDThe significant risks posed to mothers and fetuses by COVID-19 in pregnancy have sparked a worldwide debate surrounding the pros and cons of antenatal SARS-CoV-2 inoculation, as we lack sufficient evidence regarding vaccine effectiveness in pregnant women and their offspring. We aimed to provide substantial evidence for the effect of the BNT162b2 mRNA vaccine versus native infection on maternal humoral, as well as transplacentally acquired fetal immune response, potentially providing newborn protection.METHODSA multicenter study where parturients presenting for delivery were recruited at 8 medical centers across Israel and assigned to 3 study groups: vaccinated (n = 86); PCR-confirmed SARS-CoV-2 infected during pregnancy (n = 65), and unvaccinated noninfected controls (n = 62). Maternal and fetal blood samples were collected from parturients prior to delivery and from the umbilical cord following delivery, respectively. Sera IgG and IgM titers were measured using the Milliplex MAP SARS-CoV-2 Antigen Panel (for S1, S2, RBD, and N).RESULTSThe BNT162b2 mRNA vaccine elicits strong maternal humoral IgG response (anti-S and RBD) that crosses the placenta barrier and approaches maternal titers in the fetus within 15 days following the first dose. Maternal to neonatal anti-COVID-19 antibodies ratio did not differ when comparing sensitization (vaccine vs. infection). IgG transfer ratio at birth was significantly lower for third-trimester as compared with second trimester infection. Lastly, fetal IgM response was detected in 5 neonates, all in the infected group.CONCLUSIONAntenatal BNT162b2 mRNA vaccination induces a robust maternal humoral response that effectively transfers to the fetus, supporting the role of vaccination during pregnancy.FUNDINGIsrael Science Foundation and the Weizmann Institute Fondazione Henry Krenter. 相似文献
53.
George Pentheroudakis Yael Spector Dimitrios Krikelis Vassiliki Kotoula Eti Meiri Vassiliki Malamou-Mitsi George Fountzilas Mats Sanden Nicholas Pavlidis Hila Benjamin Ranit Aharonov 《Clinical & experimental metastasis》2013,30(4):431-439
No data exist on biologic differences between Cancer of unknown primary (CUP) and metastatic solid tumors of known primary site. We assigned a primary tissue of origin in 40 favorable CUP patients (A: serous peritoneal carcinomatosis n = 14, B: axillary adenocarcinoma n = 8, C: upper squamous cervical adenopathy n = 18) by means of a 64-microRNA assay. Subsequently, we profiled the expression of 733 microRNAs (miRs) in the CUP cases and compared results with metastases from 20 ovarian carcinomas, 10 breast adenocarcinomas, 20 squamous head neck or lung tumors. In the Peritoneal CUP versus Ovarian (Known Primary Metastases) KPM comparison, a total of 12 miR were significantly differentially expressed: higher than twofold expression difference in CUP was seen only for miR-513a-5p (3.7-fold upregulated) and miR-483-5p (2.5-fold upregulated), while miR-708 exhibited a twofold downregulation. In the Breast CUP versus Breast KPM comparison, only miR-29c that were downregulated in CUP by 2.7-fold satisfied the FDR threshold. miR-30e and miR-27b, downregulated in ovarian CUPs versus KPMs, were also non-significantly downregulated in breast CUP by 2.0- and 1.4-fold respectively. Six miRs, which belong to the 17–92 oncocluster showed a trend of upregulation in Breast CUP versus Breast KPM cases. A CUP signature remains elusive. 相似文献
54.
Itai Spector Yael Zilberstein Adi Lavy Olga Genin Hila Barzilai-Tutsch Ana Bodanovsky Orna Halevy Mark Pines 《The American journal of pathology》2013,182(3):905-916
Apolipoprotein E4 (APOE4) genotype is the strongest genetic risk factor for late-onset Alzheimer disease and confers a proinflammatory, neurotoxic phenotype to microglia. Here, we tested the hypothesis that bone marrow cell APOE genotype modulates pathological progression in experimental Alzheimer disease. We performed bone marrow transplants (BMT) from green fluorescent protein–expressing human APOE3/3 or APOE4/4 donor mice into lethally irradiated 5-month-old APPswe/PS1ΔE9 mice. Eight months later, APOE4/4 BMT–recipient APPswe/PS1ΔE9 mice had significantly impaired spatial working memory and increased detergent-soluble and plaque Aβ compared with APOE3/3 BMT–recipient APPswe/PS1ΔE9 mice. BMT-derived microglia engraftment was significantly reduced in APOE4/4 recipients, who also had correspondingly less cerebral apoE. Gene expression analysis in cerebral cortex of APOE3/3 BMT recipients showed reduced expression of tumor necrosis factor-α and macrophage migration inhibitory factor (both neurotoxic cytokines) and elevated immunomodulatory IL-10 expression in APOE3/3 recipients compared with those that received APOE4/4 bone marrow. This was not due to detectable APOE-specific differences in expression of microglial major histocompatibility complex class II, C-C chemokine receptor (CCR) type 1, CCR2, CX3C chemokine receptor 1 (CX3CR1), or C5a anaphylatoxin chemotactic receptor (C5aR). Together, these findings suggest that BMT-derived APOE3-expressing cells are superior to those that express APOE4 in their ability to mitigate the behavioral and neuropathological changes in experimental Alzheimer disease.Humans uniquely have three different apolipoprotein E (APOE) alleles (ɛ2, ɛ3, and ɛ4). APOE4 is the single greatest genetic risk factor for late-onset Alzheimer disease (AD), and there is a gene dosage effect.1 However, genetic association does not inform function/pathogenesis. Multiple mechanisms have been postulated that predominantly focus on production, metabolism, or clearance of amyloid-β (Aβ) and that are variably supported by multiple observations, including: i) APOE genotype is strongly related to Aβ levels in brain and cerebrospinal fluid of AD patients2,3; ii) modulation of apolipoprotein E (apoE) protein levels in brain results in alterations of Aβ burden4,5; iii) Aβ degradation is at least partially apoE dependent6,7; and iv) Aβ clearance is differentially modulated by apoE isoforms, with APOE4 mice exhibiting reduced central and peripheral Aβ clearance compared with APOE3 mice.8–10 Aβ degradation and clearance is at least partially dependent on microglia, the innate immune effector cells of the brain. Microglia have migratory and phagocytic capacity, are increased in the vicinity of Aβ plaques, and phagocytose Aβ.11–13
APOE genotype modulates central nervous system innate immune function in culture,14 including astrocyte and microglia elaboration of cytokines and chemokines,15,16 microglia production of reactive oxygen species,17 microglia-mediated paracrine neurotoxicity,18 microglia migration,19 and other functions.20 However, the specific contribution of microglial APOE genotype to AD pathophysiology in vivo is largely unknown.To address this critical question and to test a potential therapeutic application, we used the fact that bone marrow transplantation (BMT) results in the gradual replacement of endogenous (host) microglia (to the near exclusion of other cell types) with microglia derived from donor marrow, in both wild-type mice and transgenic mouse models of AD.21–24 We used targeted-replacement (TR) APOE mice homozygous for either the APOE3 or APOE4 gene inserted into the mouse APOE regulatory elements25,26 that coexpressed green fluorescent protein (GFP). We transplanted whole bone marrow (BM) isolated from TR APOE3/3;GFP or TR APOE4/4;GFP mice into lethally irradiated APPswe/PS1ΔE9 mice to determine the specific role of microglial APOE genotype in the pathological progression of AD. 相似文献
55.
Yael H. Edrey David X. Medina Maria Gaczynska Pawel A. Osmulski Salvatore Oddo Antonella Caccamo Rochelle Buffenstein 《Neurobiology of aging》2013
Amyloid beta (Aβ) is implicated in Alzheimer's disease (AD) as an integral component of both neural toxicity and plaque formation. Brains of the longest-lived rodents, naked mole-rats (NMRs) approximately 32 years of age, had levels of Aβ similar to those of the 3xTg-AD mouse model of AD. Interestingly, there was no evidence of extracellular plaques, nor was there an age-related increase in Aβ levels in the individuals examined (2–20+ years). The NMR Aβ peptide showed greater homology to the human sequence than to the mouse sequence, differing by only 1 amino acid from the former. This subtle difference led to interspecies differences in aggregation propensity but not neurotoxicity; NMR Aβ was less prone to aggregation than human Aβ. Nevertheless, both NMR and human Aβ were equally toxic to mouse hippocampal neurons, suggesting that Aβ neurotoxicity and aggregation properties were not coupled. Understanding how NMRs acquire and tolerate high levels of Aβ with no plaque formation could provide useful insights into AD, and may elucidate protective mechanisms that delay AD progression. 相似文献
56.
57.
Asal Milhem Hanifa J. Abu ToamihAtamni Luna Karkar Yael HouriHaddad Fuad A. Iraqi 《动物模型与实验医学(英文)》2021,4(1):27
BackgroundMultimorbidity of intestinal cancer (IC), type 2 diabetes (T2D) and obesity is a complex set of diseases, affected by environmental and genetic risk factors. High‐fat diet (HFD) and oral bacterial infection play important roles in the etiology of these diseases through inflammation and various biological mechanisms.MethodsTo study the complexity of this multimorbidity, we used the collaborative cross (CC) mouse genetics reference population. We aimed to study the multimorbidity of IC, T2D, and obesity using CC lines, measuring their responses to HFD and oral bacterial infection. The study used 63 mice of both sexes generated from two CC lines (IL557 and IL711). For 12 weeks, experimental mice were maintained on specific dietary regimes combined with co‐infection with oral bacteria Porphyromonas gingivalis and Fusobacterium nucleatum, while control groups were not infected. Body weight (BW) and results of a intraperitoneal glucose tolerance test (IPGTT) were recorded at the end of 12 weeks, after which length and size of the intestines were assessed for polyp counts.ResultsPolyp counts ranged between 2 and 10 per CC line. The combination of HFD and infection significantly reduced (P < .01) the colon polyp size of IL557 females to 2.5 cm2, compared to the other groups. Comparing BW gain, IL557 males on HFD gained 18 g, while the females gained 10 g under the same conditions and showed the highest area under curve (AUC) values of 40 000‐45 000 (min mg/dL) in the IPGTT.ConclusionThe results show that mice from different genetic backgrounds respond differently to a high fat diet and oral infection in terms of polyp development and glucose tolerance, and this effect is gender related. 相似文献
58.
Assaf Menachem Joab Chapman Yael Deri Chaim G. Pick Aviva Katzav 《Clinical reviews in allergy & immunology》2013,45(2):248-255
Excessive influx of immunoglobulin (IgG) into the brain has been reported to induce central nervous system (CNS) dysfunction. Depressed patients may exhibit immune activation manifested by elevated inflammatory markers and pro-inflammatory cytokines. The brain and especially the limbic system contain high concentrations of high affinity Fc receptors. We reviewed the literature on this phenomena and present data on the behavioral effects of pooled normal IgG on the brain. Many disease states are associated with depression and we examined whether this may be linked to high IgG influx. Female Balb/C mice were injected intra-cerbroventricularly with human immunoglobulin whole molecule, or human IgG F(ab′)2 or Fc fragments. Control mice were injected with saline. The four groups were subjected to behavioral (staircase, forced swimming test, and elevated plus maze) and cognitive tests (passive avoidance test). IgG-injected mice exhibited depression-like behavior as reflected by significantly higher immobility time in the forced swimming test (p?<?0.05) and hyperactive behavior as reflected by higher number of stairs climbed in the staircase test compared to controls (p?<?0.01). Fc-fragments-injected mice showed hyperactive behavior as reflected by both higher number of stairs climbed and rearing events in the staircase test compared to controls. The results indicate that high levels of normal IgG in the cerebrospinal fluid can cause hyperactivity and depression-like behavior. The mechanism involved in these CNS manifestations include possibly Fc receptor binding. 相似文献
59.
Yael Lupu-Haber Oded Pinkas Stefanie Boehm Thomas Scheper Cornelia Kasper Marcelle Machluf 《Biomedical microdevices》2013,15(6):1055-1066
Bone tissue engineering is an alternative approach to bone grafts. In our study we aim to develop a composite scaffold for bone regeneration made of doped zirconium oxide (ZrO2) conjugated with poly(lactic-co-glycolic acid) (PLGA) particles for the delivery of growth factors. In this composite, the PLGA microspheres are designed to release a crucial growth factor for bone formation, bone morphogenetic protein-2 (BMP2). We found that by changing the polymer’s molecular weight and composition, we could control microsphere loading, release and size. The BMP2 released from PLGA microspheres retained its biological activity and increased osteoblastic marker expression in human mesenchymal stem cells (hMSCs). Uncapped PLGA microspheres were conjugated to ZrO2 scaffolds using carbodiimide chemistry, and the composite scaffold was shown to support hMSCs growth. We also demonstrated that human umbilical vein endothelial cells (HUVECs) can be co-cultured with hMSCs on the ZrO2 scaffold for future vascularization of the scaffold. The ZrO2 composite scaffold could serve as a bone substitute for bone grafting applications with the added ability of releasing different growth factors needed for bone regeneration. 相似文献
60.
Yael Lahav David Levy Avi Ohry Gabi Zeilig Meir Lahav Hava Golander Anat-Chacham Guber Orit Uziel Ruth Defrin 《The journal of pain》2021,22(2):209-218
Chronic pain induces a multitude of harmful effects; recently it has been suggested that chronic pain is also associated with premature aging, manifested in shortened telomere length (TL). However, evidence for this hypothesis is scarce and inconsistent. The aim was twofold: 1) Investigate whether chronic pain is associated with premature aging, and 2) Determine whether physical exercise (PE) moderates this association if it exists. Participants were 116 male subjects, with (n = 67) and without chronic pain (n = 49). Blood samples for TL analysis were collected and participants were interviewed and completed questionnaires. As a part of the cohort, we included people with physical disability; this variable was controlled in the analysis. The TL of individuals with chronic pain was significantly shorter than that of pain-free individuals. Regression analysis revealed a significant moderating effect of PE on chronic pain and TL, above and beyond the effects of disability, age, and weight. Whereas chronic pain was associated with shorter telomeres in participants who did not exercise, this association was nonsignificant among participants who did exercise. The results suggest that chronic pain is associated with premature ageing; however, PE may mitigate this association and may protect individuals against the harmful effects of chronic pain.PerspectiveThe study suggests that it is important to monitor signs of premature ageing among chronic pain patients as they are at risk. However, chronic pain patients may benefit from regular PE in this respect as it may moderate premature ageing. 相似文献