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El Hawary R, Meshaal S, Deswarte C, Galal N, Abdelkawy M, Alkady R, Abd Elaziz D, Freiberger T, Ravcukova B, Litzman J, Bustamante J, Boutros J, Gaafar T, Elmarsafy A
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Role of Flow Cytometry in the Diagnosis of Chronic Granulomatous Disease: the Egyptian Experience (opens in new window)

JOURNAL OF CLINICAL IMMUNOLOGY 2016 AUG; 36(6):610-618
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Chronic granulomatous disease (CGD) is an inherited mutational defect in any of the NADPH oxidase complex, CYBB (gp91-phox), NCF1 (p47-phox), CYBA (p22-phox), NCF2 (p67-phox), or NCF4 (p40-phox) leading to inability of phagocytes to perform effective respiratory burst and thus diminished killing of bacteria and fungi. The identification of defective proteins aids in establishing a diagnosis prior to genetic analysis, which is rather labor-intensive, expensive, and time-consuming. The present study aims at assessing the NADPH proteins by performing the intracellular staining with specific monoclonal antibodies and their assessment on flow cytometry. The use of flow cytometry is less laborious and faster to perform than western blot. It also confirms the diagnosis of CGD and detects the affected components allowing proper management of patients. Twenty-eight patients from 25 different kindred, clinically suspected as CGD were recruited in Egypt. Dihydrorhodamine test was performed to confirm the diagnosis of the patients. Intracellular staining of NADPH components using specific monoclonal antibodies was performed followed by flow cytometric analysis. The present study revealed that the most common defective protein in our cohort is p22-phox, found in 13 patients (46.4 % of cases) followed by p47-phox in 8 patients (28.6 %), gp91-phox in 5 patients (17.9 %), and finally p67-phox in 2 patients (7.1 %). In countries with limited resources and yet large number of CGD patients, the analysis of the defective proteins by flow cytometry is an optimum solution for confirming the diagnosis and is a step for targeted sequencing in families seeking prenatal diagnosis.
Capoor MN, Ruzicka F, Machackova T, Jancalek R, Smrcka M, Schmitz JE, Hermanova M, Sana J, Michu E, Baird JC, Ahmed FS, Maca K, Lipina R, Alamin TF, Coscia MF, Stonemetz JL, Witham T, Ehrlich GD, Gokaslan ZL, Mavrommatis K, Birkenmaier C, Fischetti VA, Slaby O
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Prevalence of Propionibacterium acnes in Intervertebral Discs of Patients Undergoing Lumbar Microdiscectomy: A Prospective Cross-Sectional Study (opens in new window)

PLOS ONE 2016 AUG 18; 11(8):? Article e0161676
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Background The relationship between intervertebral disc degeneration and chronic infection by Propionibacterium acnes is controversial with contradictory evidence available in the literature. Previous studies investigating these relationships were under-powered and fraught with methodical differences; moreover, they have not taken into consideration P. acnes' ability to form biofilms or attempted to quantitate the bioburden with regard to determining bacterial counts/genome equivalents as criteria to differentiate true infection from contamination. The aim of this prospective cross-sectional study was to determine the prevalence of P. acnes in patients undergoing lumbar disc microdiscectomy. Methods and Findings The sample consisted of 290 adult patients undergoing lumbar microdiscectomy for symptomatic lumbar disc herniation. An intraoperative biopsy and pre-operative clinical data were taken in all cases. One biopsy fragment was homogenized and used for quantitative anaerobic culture and a second was frozen and used for real-time PCR-based quantification of P. acnes genomes. P. acnes was identified in 115 cases (40%), coagulase-negative staphylococci in 31 cases (11%) and alpha-hemolytic streptococci in 8 cases (3%). P. acnes counts ranged from 100 to 9000 CFU/ml with a median of 400 CFU/ml. The prevalence of intervertebral discs with abundant P. acnes (>= 1x10(3) CFU/ml) was 11% (39 cases). There was significant correlation between the bacterial counts obtained by culture and the number of P. acnes genomes detected by real-time PCR (r = 0.4363, p<0.0001). Conclusions In a large series of patients, the prevalence of discs with abundant P. acnes was 11%. We believe, disc tissue homogenization releases P. acnes from the biofilm so that they can then potentially be cultured, reducing the rate of false-negative cultures. Further, quantification study revealing significant bioburden based on both culture and real-time PCR minimize the likelihood that observed findings are due to contamination and supports the hypothesis P. acnes acts as a pathogen in these cases of degenerative disc disease.
Van Kempen TA, Narayan A, Waters EM, Marques-Lopes J, Iadecola C, Glass MJ, Pickel VM, Milner TA
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Alterations in the Subcellular Distribution of NADPH Oxidase p47(phox) in Hypothalamic Paraventricular Neurons Following Slow-Pressor Angiotensin II Hypertension in Female Mice With Accelerated Ovarian Failure (opens in new window)

JOURNAL OF COMPARATIVE NEUROLOGY 2016 AUG 1; 524(11):2251-2265
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At younger ages, women have a lower risk for hypertension than men, but this sexual dimorphism declines with the onset of menopause. These differences are paralleled in rodents following "slow-pressor" angiotensin II (AngII) administration: young male and aged female mice, but not young females, develop hypertension. There is also an established sexual dimorphism both in the cardiovascular response to the neurohypophyseal hormone arginine vasopressin (AVP) and in the expression of oxidative stress. We examined the relationship between AngII-mediated hypertension and the cellular distribution of the superoxide generating NADPH oxidase (NOX) in AVP-expressing hypothalamic paraventricular nucleus (PVN) neurons in "menopausal" female mice. Dual-labeling immunoelectron microscopy was used to determine whether the subcellular distribution of the organizer/adapter NOX p47(phox) subunit is altered in PVN dendrites following AngII administered (14 days) during the "postmenopausal" stage of accelerated ovarian failure (AOF) in young female mice treated with 4-vinylcyclohexene diepoxide. Slow-pressor AngII elevated blood pressure in AOF females and induced a significant increase in near plasmalemmal p47(phox) and a decrease in cytoplasmic p47(phox) in PVN AVP dendrites. These changes are the opposite of those observed in AngII-induced hypertensive male mice (Coleman et al. [2013] J. Neurosci. 33:4308-4316) and may be ascribed in part to baseline differences between young females and males in the near plasmalemmal p47(phox) on AVP dendrites seen in the present study. These findings highlight fundamental differences in the neural substrates of oxidative stress in the PVN associated with AngII hypertension in postmenopausal females compared with males. (C) 2015 Wiley Periodicals, Inc.
Li XM, Huang J, Zhang M, Funakoshi R, Sheetij D, Spaccapelo R, Crisanti A, Nussenzweig V, Nussenzweig RS, Tsuji M
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Human CD8+T cells mediate protective immunity induced by a human malaria vaccine in human immune system mice (opens in new window)

VACCINE 2016 AUG 31; 34(38):4501-4506
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A number of studies have shown that CD8+ T cells mediate protective anti-malaria immunity in a mouse model. However, whether human CD8+ T cells play a role in protection against malaria remains unknown. We recently established human immune system (HIS) mice harboring functional human CD8+ T cells (HIS-CD8 mice) by transduction with HLA-A*0201 and certain human cytokines using recombinant adeno-associated virus-based gene transfer technologies. These HIS-CD8 mice mount a potent, antigen-specific HLA-A*0201-restricted human CD8+ T-cell response upon immunization with a recombinant adenovirus expressing a human malaria antigen, the Plasmodium falciparum circumsporozoite protein (PfCSP), termed AdPfCSP. In the present study, we challenged AdPfCSP-immunized HIS-CD8 mice with transgenic Plasmodium berghei sporozoites expressing full-length PfCSP and found that AdPfCSP-immunized (but not naive) mice were protected against subsequent malaria challenge. The level of the HLA-A*0201-restricted, PfCSP-specific human CD8+ T-cell response was closely correlated with the level of malaria protection. Furthermore, depletion of human CD8+ T cells from AdPfCSP-immunized HIS-CD8 mice almost completely abolished the anti -malaria immune response. Taken together, our data show that human CD8+ T cells mediate protective anti-malaria immunity in vivo. (C) 2016 The Author(s). Published by Elsevier Ltd.
Bastia D, Srivastava P, Zaman S, Choudhury M, Mohanty BK, Bacal J, Langston LD, Pasero P, O'Donnell ME
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Phosphorylation of CMG helicase and Tof1 is required for programmed fork arrest (vol 113, pg E3639, 2016) (opens in new window)

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA 2016 AUG 2; 113(31):E4577-E4577
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York A, Kutluay SB, Errando M, Bieniasz PD
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The RNA Binding Specificity of Human APOBEC3 Proteins Resembles That of HIV-1 Nucleocapsid (opens in new window)

PLOS PATHOGENS 2016 AUG; 12(8):? Article e1005833
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The APOBEC3 (A3) cytidine deaminases are antiretroviral proteins, whose targets include human immunodeficiency virus type-1 (HIV-1). Their incorporation into viral particles is critical for antiviral activity and is driven by interactions with the RNA molecules that are packaged into virions. However, it is unclear whether A3 proteins preferentially target RNA molecules that are destined to be packaged and if so, how. Using cross-linking immunoprecipitation sequencing (CLIP-seq), we determined the RNA binding preferences of the A3F, A3G and A3H proteins. We found that A3 proteins bind preferentially to RNA segments with particular properties, both in cells and in virions. Specifically, A3 proteins target RNA sequences that are G-rich and/or A-rich and are not scanned by ribosomes during translation. Comparative analyses of HIV-1 Gag, nucleocapsid (NC) and A3 RNA binding to HIV-1 RNA in cells and virions revealed the striking finding that A3 proteins partially mimic the RNA binding specificity of the HIV-1 NC protein. These findings suggest a model for A3 incorporation into HIV-1 virions in which an NC-like RNA binding specificity is determined by nucleotide composition rather than sequence. This model reconciles the promiscuity of A3 RNA binding that has been observed in previous studies with a presumed advantage that would accompany selective binding to RNAs that are destined to be packaged into virions.
Alabi RO, Glomski K, Haxaire C, Weskamp G, Monette S, Blobel CP
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ADAM10-Dependent Signaling Through Notchl and Notch4 Controls Development of Organ-Specific Vascular Beds (opens in new window)

CIRCULATION RESEARCH 2016 AUG 5; 119(4):519-+
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Rationale: Endothelial Notch signaling is critical for early vascular development and survival. Yet, previously described mice lacking endothelial a disintegrin and metalloproteinase 10 (ADAM10), a key regulator of Notch signaling, survived into adulthood with organ-specific vascular defects. These findings raised questions about whether these vascular defects were related to Notch signaling or other functions of ADAM10. Objective: The aims of the study are to determine whether compensatory or redundant functions of ADAM17 in Notch signaling can explain the survival of Adam10 Delta EC mice, explore the contribution of different Tie2-Cre transgenes to the differences in survival, and establish whether the Adam10 Delta EC vascular phenotypes can he recapitulated by inactivation of Notch receptors in endothelial cells. Methods and Results: Mice lacking ADAM10 and ADAM17 in endothelial cells (Adam10/Adam17 Delta EC), which survived postnatally with organ-specific vascular defects, resembled Adam10 Delta EC mice. In contrast, Adam10 Delta EC mice generated with the Tie2Cre transgene previously used to inactivate endothelial Notch (Adam10 Delta ECFlv) died by E10.5. Quantitative polymerase chain reaction analysis demonstrated that Cre-mediated recombination occurs earlier in Adam10 Delta ECFlv mice than in the previously described Adam10 Delta EC mice. Finally, mice lacking endothelial Notchl (Notch1 Delta EC) share some organ-specific vascular defects with Adam10 Delta EC mice, whereas Notch4(-/-) mice lacking endothelial Notchl (Notch1 Delta EC/Notch4(-/-)) had defects in all vascular beds affected in Adam10 Delta EC mice. Conclusions: Our results argue against a major role for ADAM17 in endothelial Notch signaling and clarify the difference in phenotypes of previously described mice lacking ADAM10 or Notch in endothelial cells. Most notably, these findings uncover new roles for Notch signaling in the development of organ-specific vascular beds.
Thinon E, Morales-Sanfrutos J, Mann DJ, Tate EW
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N-Myristoyltransferase Inhibition Induces ER-Stress, Cell Cycle Arrest, and Apoptosis in Cancer Cells (opens in new window)

ACS CHEMICAL BIOLOGY 2016 AUG; 11(8):2165-2176
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N-Myristoyltransferase (NMT) covalently attaches a C14 fatty acid to the N-terminal glycine of proteins and has been proposed as a therapeutic target in cancer. We have recently shown that selective NMT inhibition leads to dose-responsive loss of N-myristoylation on more than 100 protein targets in cells, and cytotoxicity in cancer cells. N-myristoylation lies upstream of multiple pro-proliferative and oncogenic pathways, but to date the complex substrate specificity of NMT has limited determination of which diseases are most likely to respond to a selective NMT inhibitor. We describe here the phenotype of NMT inhibition in HeLa cells and show that cells die through apoptosis following or concurrent with accumulation in the G1 phase. We used quantitative proteomics to map protein expression changes for more than 2700 proteins in response to treatment with an NMT inhibitor in HeLa cells and observed down-regulation of proteins involved in cell cycle regulation and up-regulation of proteins involved in the endoplasmic reticulum stress and unfolded protein response, with similar results in breast (MCF-7, MDA-MB-231) and colon (HCT116) cancer cell lines. This study describes the cellular response to NMT inhibition at the proteome level and provides a starting point for selective targeting of specific diseases with NMT inhibitors, potentially in combination with other targeted agents.
Li HD, Bielas SL, Zaki MS, Ismail S, Farfara D, Um K, Rosti RO, Scott EC, Tu S, Chi NC, Gabriel S, Erson-Omay EZ, Ercan-Sencicek AG, Yasuno K, Caglayan AO, Kaymakcalan H, Ekici B, Bilguvar K, Gunel M, Gleeson JG
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Biallelic Mutations in Citron Kinase Link Mitotic Cytokinesis to Human Primary Microcephaly (opens in new window)

AMERICAN JOURNAL OF HUMAN GENETICS 2016 AUG 4; 99(2):501-510
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Cell division terminates with cytokinesis and cellular separation. Autosomal-recessive primary microcephaly (PMCPH) is a neurodevelopmental disorder characterized by a reduction in brain and head size at birth in addition to non-progressive intellectual disability. MCPH is genetically heterogeneous, and 16 loci are known to be associated with loss-of-function mutations predominantly affecting centrosomal-associated proteins, but the multiple roles of centrosomes in cellular function has left questions about etiology. Here, we identified three families affected by homozygous missense mutations in CIT, encoding citron rho-interacting kinase (CIT), which has established roles in cytokinesis. All mutations caused substitution of conserved amino acid residues in the kinase domain and impaired kinase activity. Neural progenitors that were differentiated from induced pluripotent stem cells (iPSCs) derived from individuals with these mutations exhibited abnormal cytokinesis with delayed mitosis, multipolar spindles, and increased apoptosis, rescued by CRISPR/Cas9 genome editing. Our results highlight the importance of cytokinesis in the pathology of primary microcephaly.
Batista P, Deren S, Banfield A, Silva E, Cruz M, Garnes P, Cleland CM, Mehandru S, LaMar M, Markowitz M
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Challenges in Recruiting People Who Use Drugs for HIV-Related Biomedical Research: Perspectives from the Field (opens in new window)

AIDS PATIENT CARE AND STDS 2016 AUG; 30(8):379-384
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Recruitment of people who use drugs (PWUD) for HIV-related research has been undertaken since early in the epidemic. In early studies, recruitment was often performed by outreach workers with familiarity with the target population, who distributed risk reduction materials, and administered the surveys being conducted on drug use and risk behaviors. The evolution of effective treatments for HIV has provided opportunities for PWUD to participate in biobehavioral studies testing the efficacy of medical treatment advances and exploring the underlying biomedical basis for prevention and treatment efforts. Recruitment for these studies has led to new challenges for outreach workers and institutions conducting this research. PWUD, particularly those from race/ethnic minority populations, have had lower rates of engagement in HIV care and have been underrepresented in HIV/AIDS medical studies. To address these health disparities, enhanced efforts are needed to increase their participation in biomedical studies. This article examines the challenges identified by experienced outreach workers in recruiting PWUD for HIV-related biomedical studies, including individual (participant)-, institutional-, and recruiter-level challenges, and provides recommendations for addressing them.