Searched for: school:SOM
Department/Unit:Cell Biology
Impaired reproductive function in a woman with a telomeropathy [Meeting Abstract]
Robinson, L G; Kramer, Y G; Pimentel, R N; Wang, F; Keefe, D L
OBJECTIVE: Telomere attrition may mediate some of the effects of aging on reproductive function in women. Mice null or haploinsufficient for telomerase phenocopy the profile of reproductive aging in women, with progressive infertility caused by numerous defects in their reproductive cells. Telomeropathies, such as Dyskeratosis Congenita, provide a natural experiment to test the Telomere Theory of Reproductive Aging in women. This study attempts to extensively characterize the reproductive function in women with telomeropathies for the first time. DESIGN: Blood samples, cumulus cells, and arrested embryos were collected following the cycle of A 30 year old woman with a precocious aging syndrome and aplastic anemia, attributed to a telomeropathy (AMH=0.3 and AFC=8). She underwent, controlled ovarian stimulation with E2 prime protocol and 600 IU/day of gonadotropin, using mixed protocol and GnRH antagonist for 18 days. MATERIALS AND METHODS: Monochrome multiplex quantitative polymerase chain reaction (qPCR) assay (Cawthon 2009) measured telomere length in leukocytes extracted from whole blood as well as, cumulus cells stripped from retrieved follicles. Telomere (T) amplification was normalized to a single copy gene (S), resulting in a T/S ratio proportional to average telomere length in the population. Single-Cell Amplification of Telomere Repeats (SCATR) PCR (Wang 2013) was used to measure telomere length in discarded embryo blastomeres. Telomere (T) amplification was normalized a reference gene (R), producing a T/R ratio . One-Way ANOVA test was used to determine statistical significance. RESULTS: Hyperstimulation resulted in only 7 oocytes and 1 euploid blastocyst. Over the treatment course, leukocyte telomere length increased from T/S ratio= 0.192+/-.0157 to 0.234+/-.0306 and there was a statistically significant (p= .0256) linear increase during the treatment. Further, telomere length in a retrieved parthenogenetic, 2-cell embryo was (T/R average= .169+/-.021) and that in cumulus cells (T/S= 0.586+/-.0147). Telomere lengths in all assayed cell types were shorter than those from age matched controls. CONCLUSIONS: Young woman with reduced ovarian reserve, poor response to ovarian stimulation and a high percentage of arrested embryos and aneuploid embryos was still able to generate one euploid blastocyst with high dose controlled ovarian stimulation, demonstrating the promise of ART for fertility preservation in women with telomeropathies. Intriguingly, controlled ovarian hyperstimulation increased her leukocyte telomere length. Presumably, the supraphysiologic levels of estrogen activated telomerase activity, consistent with prior studies reporting an estrogen response element in the TERT gene. Future studies should examine whether women with telomeropathies may benefit from estrogen supplementation
EMBASE:612867897
ISSN: 1556-5653
CID: 2300162
Specialized Roles of Neurofilament Proteins in Synapses: Relevance to Neuropsychiatric Disorders
Yuan, Aidong; Nixon, Ralph A
Neurofilaments are uniquely complex among classes of intermediate filaments in being composed of four subunits (NFL, NFM, NFH and alpha-internexin in the CNS) that differ in structure, regulation, and function. Although neurofilaments have been traditionally viewed as axonal structural components, recent evidence has revealed that distinctive assemblies of neurofilament subunits are integral components of synapses, especially at postsynaptic sites. Within the synaptic compartment, the individual subunits differentially modulate neurotransmission and behavior through interactions with specific neurotransmitter receptors. These newly uncovered functions suggest that alterations of neurofilament proteins not only underlie axonopathy in various neurological disorders but also may play vital roles in cognition and neuropsychiatric diseases. Here, we review evidence that synaptic neurofilament proteins are a sizable population in the CNS and we advance the concept that changes in the levels or post-translational modification of individual NF subunits contribute to synaptic and behavioral dysfunction in certain neuropsychiatric conditions.
PMCID:5079776
PMID: 27609296
ISSN: 1873-2747
CID: 2238682
Cell-type-specific profiling of protein-DNA interactions without cell isolation using targeted DamID with next-generation sequencing
Marshall, Owen J; Southall, Tony D; Cheetham, Seth W; Brand, Andrea H
This protocol is an extension to: Nat. Protoc. 2, 1467-1478 (2007); doi:10.1038/nprot.2007.148; published online 7 June 2007The ability to profile transcription and chromatin binding in a cell-type-specific manner is a powerful aid to understanding cell-fate specification and cellular function in multicellular organisms. We recently developed targeted DamID (TaDa) to enable genome-wide, cell-type-specific profiling of DNA- and chromatin-binding proteins in vivo without cell isolation. As a protocol extension, this article describes substantial modifications to an existing protocol, and it offers additional applications. TaDa builds upon DamID, a technique for detecting genome-wide DNA-binding profiles of proteins, by coupling it with the GAL4 system in Drosophila to enable both temporal and spatial resolution. TaDa ensures that Dam-fusion proteins are expressed at very low levels, thus avoiding toxicity and potential artifacts from overexpression. The modifications to the core DamID technique presented here also increase the speed of sample processing and throughput, and adapt the method to next-generation sequencing technology. TaDa is robust, reproducible and highly sensitive. Compared with other methods for cell-type-specific profiling, the technique requires no cell-sorting, cross-linking or antisera, and binding profiles can be generated from as few as 10,000 total induced cells. By profiling the genome-wide binding of RNA polymerase II (Pol II), TaDa can also identify transcribed genes in a cell-type-specific manner. Here we describe a detailed protocol for carrying out TaDa experiments and preparing the material for next-generation sequencing. Although we developed TaDa in Drosophila, it should be easily adapted to other organisms with an inducible expression system. Once transgenic animals are obtained, the entire experimental procedure-from collecting tissue samples to generating sequencing libraries-can be accomplished within 5 d.
PMCID:7032955
PMID: 27490632
ISSN: 1750-2799
CID: 5193312
Selective serotonin reuptake inhibitors and dental implant osseointegration [Meeting Abstract]
Tolomeo, P G; Lee, J S; Miller, E J
Selective serotonin reuptake inhibitors (SSRIs) are a class of antidepressants that are utilized to treatmajor depressive disorders and anxiety disorders; SSRIs are the most widely used antidepressants worldwide.3 Past literature on SSRIs have documented that use of SSRIs reduce bone formation thus increasing the risk of bone fracture. Inhibiting the reuptake of 5-HTs results in increased osteoclast differentiation and inhibition of osteoblast proliferation, leading to an overall decrease in bone mass and bone mineral density. 1Recent studies have suggested that use of SSRIs is associated with increased risk of dental implant failure, although other studies involving bone loss and remodeling have reported conflicting results. In addition to SSRIs, proton- proton inhibitors and anti-epileptic drugs have also been implicated in impaired bone remodeling. We conducted a retrospective study on patients who completed dental implant therapy from December 2007 to January 2016 at a single institution. A total of 510 dental implants (167 implants placed in 29 patients using SSRIs) placed in 108 male patients were used to assess the risk associated with the use of SSRI. The data was analyzed with a multivariate analysis and linear regression model. Osseointegration is defined as a direct structural and functional connection between ordered living bone and the surface of a load-carrying implant, that is critical for implant stability.2 In order for implants to be considered successful, they must be fully osseointegrated with the bone and provide function. Implant failure is defined as presenting with one or more of the following: clinical signs of mobility, pain, infection, total loss of implant, radiographic bone loss and/or peri-apical pathology. The results of our study show that in patients taking an SSRI at the time of dental implant therapy, 10 implants failed and 157 were successful (5.99% failure rate), while in those who were not taking an SSRI, 20 implants failed and 323 were successful (5.83% failure rate). We found no association between SSRI and dental implant failure risk (RR = 1.03; 95% confidence interval, 0.4918-2.1443; p = 0.9436). A secondary outcome that was associated with increased failure rate was smoking habits (p = 0.03), which is in agreement with previous studies. Additionally, we did not find a dose-dependent risk of dental implant failure in patients who were taking a low-moderate vs. moderate- high dose of SSRIs (RR = 1.91, 95% confidence interval, 0.4201 -8.6981; p = 0.40) The study assessed the use of proton- pump inhibitors and anti-epileptic drugs in the above patients, demonstrating that there was no associated risk of implant failure (p =0.93; p = 0.84, respectively). Our results conclude that treatment with SSRIs is not associated with an increased failure rate of osseointegration of dental implants, which is not in agreement with previously reported studies. 4
EMBASE:620211831
ISSN: 1531-5053
CID: 2930542
Autoantibodies against tumor-associated antigens in the early detection of lung cancer
Dai, Liping; Tsay, Jun-Chieh J; Li, Jitian; Yie, Ting-An; Munger, John S; Pass, Harvey; Rom, William N; Zhang, Yi; Tan, Eng M; Zhang, Jian-Ying
OBJECTIVES: Autoantibodies against tumor-associated antigens (TAAs) identified in patients with advanced lung cancer may be detected in subjects with early lung cancer or even predate the diagnosis. The purpose of this study is to address the temporal relationship between lung cancer development and serum autoantibody response. MATERIALS AND METHODS: Two cohorts of patients with newly diagnosed lung cancer were included. The first cohort included 90 sera from patients with lung cancer (Stages I-III) and 89 normal control sera. In the second cohort, 93 serial serum samples from 25 patients with CT-scan screen-detected stage I lung cancer were collected before the diagnosis of lung cancer (average 32 months) and 56 controls were matched on age, gender, and smoking. Autoantibody levels were measured by immunoassay. RESULTS: Measurement of autoantibodies against seven TAAs (14-3-3zeta, c-Myc, MDM2, NPM1, p16, p53 and cyclin B1) individually could discriminate lung cancer patients from normal individuals in the first cohort and the area under curve (AUC) was 0.863 based on a panel of seven autoantibodies, with sensitivity of 68.9% and specificity of 79.5%. Autoantibodies in serial pre-diagnostic serum samples against the same panel of seven TAAs were detected prior to lung cancer diagnosis with sensitivity of 76.0% and specificity of 73.2% (AUC) (95%CI): 0.885 (0.797-0.973)). Elevated autoantibody levels could be detected greater than four years prior to lung cancer diagnosis. CONCLUSION: A panel of seven TAAs may enhance the early detection of lung cancer, consistent with a humoral immune response to TAAs that can be detected months to years prior to the diagnosis.
PMID: 27565936
ISSN: 1872-8332
CID: 2221692
The Structural Architecture of an Infectious Mammalian Prion Using Electron Cryomicroscopy
Vazquez-Fernandez, Ester; Vos, Matthijn R; Afanasyev, Pavel; Cebey, Lino; Sevillano, Alejandro M; Vidal, Enric; Rosa, Isaac; Renault, Ludovic; Ramos, Adriana; Peters, Peter J; Fernandez, Jose Jesus; van Heel, Marin; Young, Howard S; Requena, Jesus R; Wille, Holger
The structure of the infectious prion protein (PrPSc), which is responsible for Creutzfeldt-Jakob disease in humans and bovine spongiform encephalopathy, has escaped all attempts at elucidation due to its insolubility and propensity to aggregate. PrPSc replicates by converting the non-infectious, cellular prion protein (PrPC) into the misfolded, infectious conformer through an unknown mechanism. PrPSc and its N-terminally truncated variant, PrP 27-30, aggregate into amorphous aggregates, 2D crystals, and amyloid fibrils. The structure of these infectious conformers is essential to understanding prion replication and the development of structure-based therapeutic interventions. Here we used the repetitive organization inherent to GPI-anchorless PrP 27-30 amyloid fibrils to analyze their structure via electron cryomicroscopy. Fourier-transform analyses of averaged fibril segments indicate a repeating unit of 19.1 A. 3D reconstructions of these fibrils revealed two distinct protofilaments, and, together with a molecular volume of 18,990 A3, predicted the height of each PrP 27-30 molecule as ~17.7 A. Together, the data indicate a four-rung beta-solenoid structure as a key feature for the architecture of infectious mammalian prions. Furthermore, they allow to formulate a molecular mechanism for the replication of prions. Knowledge of the prion structure will provide important insights into the self-propagation mechanisms of protein misfolding.
PMCID:5015997
PMID: 27606840
ISSN: 1553-7374
CID: 2444432
Oocytes are more resistent to oxidative stress than embryos [Meeting Abstract]
Wang, L; Wang, F; Robinson, L G; Kramer, Y G; Seth-Smith, M L; Sachdev, N M; Keefe, D L
OBJECTIVE: Reactive oxygen species (ROS) are a major cause of aging in all tissues studied, including reproductive tissues. Recent studies demonstrate extensiveDNA damage repair capacity in oocytes (1), and genetic variation in DNA damage repair pathways is associated with reproductive lifespan in women (2). We hypothesized that MII oocytes are more resistant to oxidative stress than other stages of development. DESIGN: Prospective, randomized study of a biologic intervention on mouse oocytes and embryos. MATERIALS AND METHODS: 80 MII oocytes and 40 cleavage embryos from B6C3F1 mice (Embryotech Laboratories, Inc, USA) were thawed and exposed to oxidative stress induced by Carbonyl cyanide-4-(trifluoromethoxy) phenylhydrazone (FCCP, 750nM), which generates ROS by uncoupling mitochondrial electron transport and disrupting mitochondrial function. Oocytes and embryos were randomized into untreated controls, or 5, 10 or 20 hour exposure to FCCP. DNA damage was determined by immuno- fluorescent staining for gamma-H2AX, or by mean telomere length, measured by single-cell qPCR. Data were analyzed by chi-square test and one-way ANOVA. RESULTS: 20 hours of exposure to FCCP is lethal for all embryos. Embryos exposed to FCCP for 5 and 10 hours of FCCP show increased g- H2AX staining (5 hours- 87.5% vs. 25% positive cells P<0.05; 10 hours- 100% vs 25%, P<0.05). However, these same doses and durations of FCCP do not increase DNA damage in oocytes- there is no significant increase of gamma-H2AX positive MII oocytes compared to controls (30% in the control group, 40% in the 5-hour group and 30% in the 10-hour group, P>0.05). Significantly higher numbers of gamma-H2AX positive MII oocytes are found only in the 20-hour group (100%, P<0.05), a dose which is uniformly lethal to embryos. As previously demonstrated, 45 minutes of 750nM FCCP treatment shortens telomeres in cleavage stage mouse embryos (3). However, MII oocytes exposed to 750nM FCCP for 5, 10, or 20 hours show no statistically significant telomere shortening compared to controls (P>0.05). CONCLUSIONS: MIIoocytes are more resistant to oxidative stress than cleavage embryos
EMBASE:612867638
ISSN: 1556-5653
CID: 2300212
The Role of Stem Cell Therapeutics in Wound Healing: Current Understanding and Future Directions
Sorice, Sarah; Rustad, Kristine C; Li, Alexander Y; Gurtner, Geoffrey C
BACKGROUND:Chronic wounds present unique challenges for healthcare providers as they place patients at increased risk for various morbidities and mortality. Advances in wound care technology have expanded the treatment options available for wound management, but few products fully address the underlying core deficiencies responsible for the development of poorly healing wounds. In the future, addressing these derangements will undoubtedly play a key role in the treatment of these patients. Broad enthusiasm has surrounded the field of stem cell biology, which has shown great promise in repairing damaged tissues across numerous disease phenotypes. METHODS:In this review, we provide a comprehensive review of the literature and evaluate the present landscape of wound therapeutics while discussing the rationales and allure behind stem cell-based products. We further propose 2 challenges that remain as new stem cell-based therapies are being developed and as this technology moves toward clinical translation. RESULTS:Given the relatively young age of this newer technology in wound healing, numerous challenges continue to surround its effective use including identifying the ideal population of stem cells to use and determining the optimal cell delivery method. However, significant forward progress has been made, with several clinical trials beginning to demonstrate reliable clinical benefit. CONCLUSION/CONCLUSIONS:The upward trajectory of stem cell technologies provides an exciting opportunity to positively impact patient outcomes through the controlled application of regenerative cell-based therapy.
PMID: 27556772
ISSN: 1529-4242
CID: 3098432
Solitary fibrous tumor of the hard palate: A case report and review of the literature [Meeting Abstract]
Lee, J S; Tolomeo, P G; Cappetta, E J A; Phelan, J A; Alsabban, L
Solitary fibrous tumors (SFTs) are a relatively rare group of mesenchymal neoplasms. Klemperer and Rabin first described a case in the pleura in 1931, but SFTs have also been reported in extrapleural sites, including the oral cavity. SFTs of the oral cavity most commonly affect the buccal mucosa and tongue of female patients in their sixth decade of life. To date, only seven cases of oral SFTs located in the palate (three soft palate, four hard palate) have been documented in the literature. We present a case of a solitary fibrous tumor of the hard palate with review of the literature. A 26-year-old female with a past medical history significant for tuberous sclerosis presented to NYU College of Dentistry reporting a several year history of a painless mass of the hard palate. The mass was biopsied, initially diagnosed as cellular angiofibroma, and referred to the Department of Oral & Maxillofacial Surgery at Bellevue Hospital Center for further management. Examination revealed a 3x3 cm exophytic lesion on the right hard palate extending past the midline. The mass was non-tender to palpation and the mucosa overlying the lesion was intact without evidence of ulceration or necrosis. A CTA of the lesion showed mild prominence of vasculature along the right lateral soft and hard palate, possibly demonstrating supply from the ascending palatine artery. Postoperative surgical histopathology demonstrated a well-circumscribed, non-encapsulated lesion composed of spindle cells with admixed background slit-and-staghorn vessels in a patternless pattern. Immunohistochemical staining was diffusely positive for CD34 and Bcl-2 while negative for SMA, CD31, AE1/AE3, CAM5.2, S-100, EMA and demonstrated low KI-67 immunolabeling. SFTs constitute a heterogeneous group of rare spindlecell tumors that include benign and malignant neoplasms. Their cell of origin remains uncertain since CD34-positive spindle cells are also found in other mesenchymal neoplasms, such as giant cell angiofibromas and hemangiopericytoma, and share similar microscopic, immunohistochemical and biologic features. SFTs are usually well-demarcated and partially encapsulated neoplasms. Microscopically, SFTs show a wide range of morphological characteristics from predominantly fibrous lesions containing alternating fibrous areas and hyalinized thick-walled vessels to more cellular fibrous neoplasms with a "patternless pattern" and thinwalled branching vessels. Immunohistochemically, SFTs usually demonstrate CD34 and CD99, and vimentin positivity with variable Bcl-2, EMA and SMA positivity and are usually negative for CD68, desmin, pan-cytokeratins, and S-100 protein immunoreactivity. Malignant SFTs tend to demonstrate nuclear atypia, hypercellularity, loss of margin integrity, high mitotic rate (>4 per 10 high power fields) and lose CD34 immunoreactivity while overexpressing S-100 and p53. Our patient's lesion demonstrated positivity for only CD34 and Bcl-2, which, along with its aforementioned histological characteristics, was more consistent with the diagnosis of benign SFT than for the original diagnosis of cellular angiofibroma. CT imaging typically demonstrates SFTs as well-circumscribed, hypervascular masses with varying degrees of enhancement, necrosis or cystic change, and may show occasional internal calcification. Our patient's lesion demonstrated mild prominence of vasculature associated with the lesion with no invasion into the adjacent hard palate, consistent with a benign tumor. Due to its rare entity, SFTs are seldom considered in the differential diagnosis for submucosal masses of the oral cavity. However, reports suggest that SFTs may possess malignant characteristics and, thus, should be considered when evaluating well-circumscribed, solid masses in the oral cavity
EMBASE:620211992
ISSN: 1531-5053
CID: 2930512
Acute exposure to apolipoprotein A1 inhibits macrophage chemotaxis in vitro and monocyte recruitment in vivo
Iqbal, Asif J; Barrett, Tessa J; Taylor, Lewis; McNeill, Eileen; Manmadhan, Arun; Recio, Carlota; Carmineri, Alfredo; Brodermann, Maximillian H; White, Gemma E; Cooper, Dianne; DiDonato, Joseph A; Hazen, Stanley L; Channon, Keith M; Greaves, David R; Fisher, Edward A
Apolipoprotein A1 (apoA1) is the major protein component of high-density lipoprotein (HDL) and has well documented anti-inflammatory properties. To better understand the cellular and molecular basis of the anti-inflammatory actions of apoA1, we explored the effect of acute human apoA1 exposure on the migratory capacity of monocyte-derived cells in vitro and in vivo. Acute (20-60 min) apoA1 treatment induced a substantial (50-90%) reduction in macrophage chemotaxis to a range of chemoattractants. This acute treatment was anti-inflammatory in vivo as shown by pre-treatment of monocytes prior to adoptive transfer into an on-going murine peritonitis model. We find that apoA1 rapidly disrupts membrane lipid rafts, and as a consequence, dampens the PI3K/Akt signalling pathway that coordinates reorganization of the actin cytoskeleton and cell migration. Our data strengthen the evidence base for therapeutic apoA1 infusions in situations where reduced monocyte recruitment to sites of inflammation could have beneficial outcomes.
PMCID:5030090
PMID: 27572261
ISSN: 2050-084x
CID: 2232432