Faculty Bibliography

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

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.

Poor glycemic control in patients with diabetes mellitus (DM) has long been considered a contraindication for dental implant therapy due to the increased risk of delayed healing, infection, and microvascular/macrovascular complications. Numerous animal and human studies have also suggested poor glycemic control as a contraindication to dental implant therapy. However, recent studies have assessed implant stability over the initial four to six months after implant placement in patients with Type II DM possessingHbA1C levels as high as 12% and reported high rates of implant survival regardless of the patients' level of glycemic control. Although these results are promising, the studies were of a short duration and primarily assessed implant-related outcomes prior to restoration of the implants. In contrast to these studies, the goal of our study was to assess the effects of elevated glycemic levels on post-loaded dental implant survival. We conducted a retrospective review of patients who completed dental implant therapy at a single institution from January 2013 through December 2015. Only patients who received stage I implant placement with delayed loading and documented HbA1C values obtained within 3-months pre- or postoperatively were included in our study. These values reflect the average level of glycemic control over 60-90 days, representing the critical time period for bone metabolism, healing and osseointegration. Additional inclusion criteria included a follow-up assessment of the restored dental implant at least 1-year postimplant placement and at least 6-months post-loading. We defined loading as implants restored with either a single- unit crown, multi-unit fixed partial denture, or a removable overdenture. We defined survival as an implant lacking any signs of clinical mobility or failure of the implant to osseointegrate, pain, infection, or periimplant radiolucency. Our study consisted a total of 42 male patients with 173 implants (83 maxillary, 90 mandibular). HbA1C levels ranged from 5.5 to 12.2%. At the time of implant placement, 27 patients (102 implants) in group 1 had no history of DM(and/or HbA1C<=5.9%), 10 patients (47 implants) in group 2 had well-controlled DM (HbA1C 6-8%) and 5 patients (24 implants) in group 3 had poorly-controlled DM (HbA1C >= 8.1%). There were a total of five implant failures (2.89%), with three implant failures (three patients) in group 1, two implant failures (one patient) in group 2, and zero implant failures in group 3. We found no statistically significant difference in the number of implant failures among the three groups (p = 0.42). We also found no statistically significant difference in the percentage of implant failures among the three groups (p = 0.34). Patients with poorly controlled DM are typically not considered appropriate candidates for dental implant therapy. However, recent studies demonstrate that the effects of hyperglycemia on implant therapy remain uncertain. Although further investigation of longer-termeffects of elevated HbA1C levels is warranted, the results of our study demonstrate favorable outcomes for post-loaded dental implant survival in patients with HbA1C levels as high as 12.2%. The clinical results of our study are consistent with those of previous studies, which reported similar rates of implant survival in patients with Type II DM and elevated HbA1C levels

In this study, we have evaluated the efficacy of propidium monoazide quantitative polymerase chain reaction (PMA-qPCR) to differentiate between viable and non-viable Ancylostoma caninum ova. The newly developed method was validated using raw wastewater seeded with known numbers of A. caninum ova. Results of this study confirmed that PMA-qPCR has resulted in average of 88 % reduction (P < 0.05) in gene copy numbers for 50 % viable +50 % non-viable when compared with 100 % viable ova. A reduction of 100 % in gene copies was observed for 100 % non-viable ova when compared with 100 % viable ova. Similar reductions (79-80 %) in gene copies were observed for A. caninum ova-seeded raw wastewater samples (n = 18) collected from wastewater treatment plants (WWTPs) A and B. The newly developed PMA-qPCR method was applied to determine the viable ova of different helminths (A. caninum, A. duodenale, Necator americanus and Ascaris lumbricoides) in raw wastewater, human fecal and soil samples. None of the unseeded wastewater samples were positive for the above-mentioned helminths. N. americanus and A. lumbricoides ova were found in unseeded human fecal and soil samples. For the unseeded human fecal samples (1 g), an average gene copy concentration obtained from qPCR and PMA-qPCR was found to be similar (6.8 x 10(5) +/- 6.4 x 10(5) and 6.3 x 10(5) +/- 4.7 x 10(5)) indicating the presence of viable N. americanus ova. Among the 24 unseeded soil samples tested, only one was positive for A. lumbricoides. The mean gene copy concentration in the positively identified soil sample was 1.0 x 10(5) +/- 1.5 x 10(4) (determined by qPCR) compared to 4.9 x 10(4) +/- 3.7 x 10(3) (determined by PMA-qPCR). The newly developed PMA-qPCR methods were able to detect viable helminth ova from wastewater and soil samples and could be adapted for health risk assessment.

OBJECTIVE: Netrin-1 is a chemorepulsant and matrix protein expressed during and required for osteoclast differentiation, which also plays a role in inflammation by preventing macrophage egress. Because wear particle-induced osteolysis requires osteoclast-mediated destruction of bone, we hypothesised that blockade of Netrin-1 or Unc5b, a receptor for Netrin-1, may diminish this pathological condition. METHODS: C57BL/6 mice, 6-8 weeks old, had 3 mg of ultrahigh-molecular-weight polyethylene particles implanted over the calvaria and then received 10 microg of monoclonal antibodies for Netrin-1 or its receptors, Unc5b and deleted in colon cancer (DCC), injected intraperitoneally on a weekly basis. After 2 weeks, micro-computed tomography and histology analysis were performed. Netrin-1 expression was analysed in human tissue obtained following primary prosthesis implantation or after prosthesis revision for peri-implant osteolysis and aseptic implant loosening. RESULTS: Weekly injection of anti-Netrin-1 or anti-Unc5b-antibodies significantly reduced particle-induced bone pitting in calvaria exposed to wear particles (46+/-4% and 49+/-3% of control bone pitting, respectively, p<0.001) but anti-DCC antibody did not affect inflammatory osteolysis (80+/-7% of control bone pitting, p=ns). Anti-Netrin-1 or anti-Unc5b, but not anti-DCC, antibody treatment markedly reduced the inflammatory infiltrate and the number of tartrate resistance acid phosphatase (TRAP)-positive osteoclasts (7+/-1, 4+/-1 and 14+/-1 cells/high power field (hpf), respectively, vs 12+/-1 cells/hpf for control, p<0.001), with no significant changes in alkaline phosphatase-positive osteoblasts on bone-forming surfaces in any antibody-treated group. Netrin-1 immunostaining colocalised with CD68 staining for macrophages. The peri-implant tissues of patients undergoing prosthesis revision surgery showed an increase in Netrin-1 expression, whereas there was little Netrin-1 expression in soft tissues removed at the time of primary joint replacement. CONCLUSIONS: These results demonstrate a unique role for Netrin-1 in osteoclast biology and inflammation and may be a novel target for prevention/treatment of inflammatory osteolysis.

As a result of its importance in key RNA metabolic processes, the ribonucleolytic RNA exosome complex has been the focus of intense study for almost two decades. Research on exosome subunit assembly, cofactor and substrate interaction, enzymatic catalysis and structure have largely been conducted using complexes produced in the yeast Saccharomyces cerevisiae or in bacteria. Here, we examine different populations of endogenous exosomes from human embryonic kidney (HEK) 293 cells and test their enzymatic activity and structural integrity. We describe methods to prepare EXOSC10-containing, enzymatically active endogenous human exosomes at suitable yield and purity for in vitro biochemistry and negative stain transmission electron microscopy. This opens the door for assays designed to test the in vitro effects of putative cofactors on human exosome activity and will enable structural studies of preparations from endogenous sources.

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

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.

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.

Iron plays an especially important role in human physiological functions and pathological impairments. The superior properties of carbon nanotubes (CNTs) and their modification with bismuth and magnetic nanoparticles as developed in this work have led to an extraordinary and novel material to facilitate ultrasensitive detection in the nanomolar range. Here, we present the development of an electrochemical sensor for detection of ferrous (Fe²⁺) and ferric (Fe³⁺) iron by means of CNTs modified with bismuth and magnetic nanoparticles for higher sensitivity of detection. The sensor fabrication includes microfabrication methodologies, soft lithography, and electrodeposition. Cyclic voltammetry and differential pulse voltammetry are used for the electroanalytical studies and detection of the ions in samples. The sensor has a dynamic range of detection from 0.01 nm to 10 mm. The performance of the sensor with modified CNTs was explored for sensitivity and specificity. CNTs, modified with bismuth and magnetic nanoparticles by means of electrodeposition, enhanced the detection limit significantly down to 0.01 nm.