Faculty Bibliography

The revision of the curriculum at New York University School of Medicine in 2010, with a reduction of the preclerkship curriculum to 18 months, made it possible to offer an accelerated 3-year pathway in 2013 for students who know their career path. The goals of the program include individualizing education, reducing student debt, and integrating undergraduate and graduate medical education. This accelerated 3-year doctor of medicine (3YMD) pathway is the first program of its kind in the United States to offer conditional acceptance to residency programs in all specialties through the National Resident Matching Program. Since inception of the pathway 6 years ago, 81 students have graduated. Critical components to successfully launch and implement the program are described.Unwavering commitment to the program as a high institutional priority by the dean and vice dean for education facilitated the support required by department chairs and residency program directors and the flexibility needed for success. Alignment between the 3- and 4-year pathways has made it possible to add points of entry into the 3-year pathway during the second and third years and to shift back into the 4-year pathway, as warranted. Modifications to how 3YMD students are mentored included changing the role of the departmental advisor and adding a dedicated 3YMD pathway advisor who serves as an advocate for both the students and the program. Having a relatively large number of 3YMD students has contributed to the success of the program and facilitated acceptance by the residencies.

OBJECTIVE:gene with radiographic severity of symptomatic knee osteoarthritis (SKOA) and the risk of incident OA. We also explored these genetic polymorphisms in patients with new onset rheumatoid arthritis (RA). METHODS:haplotypes were also assessed for association with disease activity (DAS28) and plasma inflammatory markers in patients with RA. RESULTS:demonstrated that carriage of the TTG haplotype was associated with 4.1-fold (p=0.001) increased odds of incident rOA. Plasma IL-1Ra levels were lower in TTG carriers, while chondrocytes from TTG carriers exhibited decreased secretion of IL-1Ra. In patients with RA, the TTG haplotype was associated with increased DAS28, decreased plasma IL-1Ra and elevations of plasma inflammatory markers (hsCRP, interleukin 6 (IL-6)). CONCLUSION/CONCLUSIONS:TTG risk haplotype, associated with decreased IL-1Ra plasma levels, impairs endogenous 'anti-inflammatory' mechanisms.

The acceptance of students to a medical school places a considerable emphasis on performance in standardized tests and undergraduate grade point average (uGPA). Traditionally, applicants may be judged as a homogeneous population according to simple quantitative thresholds that implicitly assume a linear relationship between scores and academic success. This 'one-size-fits-all' approach ignores the notion that individuals may show distinct patterns of achievement and follow diverse paths to success. In this study, we examined a dataset composed of 53 variables extracted from the admissions application records of 1,088 students matriculating to NYU School of Medicine between the years 2006-2014. We defined training and test groups and applied K-means clustering to search for distinct groups of applicants. Building an optimized logistic regression model, we then tested the predictive value of this clustering for estimating the success of applicants in medical school, aggregating eight performance measures during the subsequent medical school training as a success factor. We found evidence for four distinct clusters of students-we termed 'signatures'-which differ most substantially according to the absolute level of the applicant's uGPA and its trajectory over the course of undergraduate education. The 'risers' signature showed a relatively higher uGPA and also steeper trajectory; the other signatures showed each remaining combination of these two main factors: 'improvers' relatively lower uGPA, steeper trajectory; 'solids' higher uGPA, flatter trajectory; 'statics' both lower uGPA and flatter trajectory. Examining the success index across signatures, we found that the risers and the statics have significantly higher and lower likelihood of quantifiable success in medical school, respectively. We also found that each signature has a unique set of features that correlate with its success in medical school. The big data approach presented here can more sensitively uncover success potential since it takes into account the inherent heterogeneity within the student population.

Osteoarthritis (OA) is characterized by progressive loss of articular cartilage accompanied by the new bone formation and, often, a synovial proliferation that culminates in pain, loss of joint function, and disability. However, the cellular and molecular mechanisms of OA progression and the relative contributions of cartilage, bone, and synovium remain unclear. We recently found that the extracellular matrix (ECM) protein periostin (Postn, or osteoblast-specific factor, OSF-2) is expressed at high levels in human OA cartilage. Multiple groups have also reported elevated expression of Postn in several rodent models of OA. We have previously reported that in vitro Postn promotes collagen and proteoglycan degradation in human chondrocytes through AKT/β-catenin signaling and downstream activation of MMP-13 and ADAMTS4 expression. Here we show that Postn induces collagen and proteoglycan degradation in cartilage by signaling through discoidin domain receptor-1 (DDR1), a receptor tyrosine kinase. The genetic deficiency or pharmacological inhibition of DDR1 in mouse chondrocytes blocks Postn-induced MMP-13 expression. These data show that Postn is signaling though DDR1 is mechanistically involved in OA pathophysiology. Specific inhibitors of DDR1 may provide therapeutic opportunities to treat OA.

Background/Purpose : Weight loss in obese patients can reduce knee osteoarthritis (OA) pain, even when physical therapy and intra-articular injections have failed. The impacts of either non-surgical or surgical weight loss on knee OA pain have been reported separately, but few studies have assessed them conjointly. While the decrease in mechanical load helps, the contribution of metabolic changes is less clear. We aimed to compare biomarker changes with weight loss as predictors of knee pain improvement, and consider a threshold of total weight loss necessary for these changes. Methods : Patients from the NYU Langone Weight Management program were screened for knee pain prior to bariatric surgery or the start of a medical weight loss (MWL) regimen. We excluded patients with autoimmune disease, recent malignancy, recent intra-articular knee injections, and lack of OA by Kellgren-Lawrence (KL) x-ray grading. The BMI, Knee Injury and Osteoarthritis Outcome Score (KOOS) for pain, and blood samples were obtained at baseline and 1, 3, 6 and 12 months for evaluation of pain and biomarker levels. Results : Of 140 patients screened, 81 were eligible and enrolled (82.7% female; BMI 45.2+/-9.6 kg/m2, 31-74; age 52+/-12 years, 30-80). A total of 49 patients had surgery (10 bypass, 30 sleeve, 9 LapBand) and 24 medical weight loss. 33 patients completed visits up to 6 months (2 bypass, 18 sleeve, 6 LapBand, 7 MWL). By 1 month, the surgical patients had lost much more total weight than the MWL group (9.8% vs 4.1 %, p=0.001), and realized marked pain relief (p< 0.001). By 6 months both groups had continued to lose weight, proportionately greater for surgical patients with further pain improvement. (Figure 1) Leptin levels dropped at 1 and then 6 months with both methods of weight loss. The pro-inflammatory protein IL-1Ra decreased significantly by 6 months in the bariatric patients, but increased with the medical regimen across both time points. Soluble vascular adhesion protein 1 (sVAP-1), another pro-inflammatory protein that facilitates leukocyte infiltration, decreased at both the 1 and 6 month intervals -but much more in MWL than in surgical patients. Consistent with the literature, the anti-inflammatory soluble receptor for advanced glycation endproducts (sRAGE) mirrored KOOS pain improvement only in surgical patients and stabilized after 1 month, but did not change in the MWL group. (Table 1) In a subgroup analysis, the 14 surgical patients who lost at least 10% of Figure 1. Surgical and medical outcomes for % total weight loss (TWL), knee pain and biomarkers Table 1. total weight by 1 month had significantly less pain at 6 months than the 12 who did not meet the threshold (DELTAKOOS 47.5 vs 29.9) but the biomarker levels were similar. (Figure 2) Conclusion : Surgical and medically supervised weight loss both lead to significant decreases in adiposity, but only those having bariatric surgery realize significant pain relief. The anatomical changes of surgical (vs. medical) weight loss result in different metabolic cascades given divergent biomarker trends. Bariatric patients who lose more than 10 percent of total body weight within the first month are more likely to have better pain relief by 6 months, but the biomarker changes reflect anatomic intervention -and are not dependent on the degree of surgical weight loss

Background/Purpose : Osteoarthritis (OA) is a highly heterogeneous disease, which suggest that multiple endotypes exist. Identification and characterization of such endotypes may assist in precision medicine for identification of faster progressors whom may benefit from a given type of intervention. Recent published data have shown that SNPs in growth factors such as TGFbeta and GDF are associated with OA, which indicate that cartilage formation and repair play an important role in progression of OA. The aim was to determine whether a biomarker of type II collagen formation measured in serum, as a potential surrogate measure of cartilage formation, could predict radiographic progression in knee OA population. Subsequently, we investigated if such a proposed low cartilage formation/repair endotype was more responsive to a potential treatment of OA. Methods : hsPRO-C2, a measurement of the type II collagen pro-peptide, was measured in blood samples of two independent knee OA cohorts: 106 recruited at New York University (NYU cohort) and 147 from the phase III OA trial SMC021-2301 (clinicaltrial.gov: NCT00486434) evaluating the efficacy and safety of oral salmon calcitonin. Patients were dichotomized based on their baseline level of hsPRO-C2 and the mean difference in two-year radiographic progression (joint space narrowing (JSN)) was analyzed using ANCOVA adjusting for baseline demographics and clinical characteristics. Results : In the NYU cohort, baseline plasma hsPRO-C2 levels were negatively correlated with the progression of radiographic JSN (r = -0.26, p = 0.009). Quartile analysis demonstrated a significant difference in mean JSN from quartile 1 to 4 (0.51 mm versus -0.07 mm, p = 0.036, fig. 1). Knee OA patients with low hsPRO-C2 levels (<= 1.48 ng/mL) revealed significantly larger JSN compared to the individuals with high hsPRO-C2 levels ( > 1.48 ng/ mL) at 24 months (0.37 mm vs 0.02 mm, p = 0.042). In the SMC cohort, there was no significant treatment effect on the medial JSN over 2 years before stratification by hsPRO-C2; however, as observed in the NYU cohort, JSN was on average higher in the low hsPRO-C2 (<= 1.96 ng/mL) group compared to the high group ( > 1.96 ng/ mL). Furthermore, in the low baseline hsPRO-C2 subgroup, sCT-treated patients on average had a lower JSN compared to placebo patients (p < 0.05, fig. 2). The opposite trend was observed in patients with high baseline hsPRO-C2. Conclusion : Here we show that low levels of cartilage formation, measured by PRO-C2, were associated with radiographic progression and greater likelihood of response to a salmon calcitonin. Low PRO-C2 may provide a measure of an OA endotype with low background cartilage formation (at baseline) and higher capacity for repair when treated with a potential cartilage anabolic drug

Background/Purpose : Early treatment initiation in rheumatoid arthritis (RA) is fundamental to avoid chronic joint destruction and disability. Despite remarkable advances in RA therapeutics, oral methotrexate (MTX) remains the anchor drug and mainstay of treatment worldwide. However, MTX bioavailability has a wide inter-individual variability and >50% of patients with moderate or severe RA show no or suboptimal improvement in their symptoms in response to MTX. The reasons for these disparities in treatment response remain unclear. Prior studies have shown that the biotransformation of MTX is altered in germ-free and microbiome-depleted mice, prompting us to hypothesize that inter-individual differences in the human gut microbiome could impact drug bioavailability and thus clinical efficacy. We sought to determine differences in the microbiome of drug-naive, new onset RA (NORA) patients that could predict response to MTX therapy. Methods : We enrolled 27 drug-naive, NORA patients priori to MTX initiation (test cohort), and classified them as either MTX-responders (MTX-R; 39% of the cohort) or non-responders (MTX-NR; 61%) based on a stringent definition of clinical response (delta improvement of DAS28 >1.8 by month 4). We performed 16S rRNA gene and Shotgun Metagenomic sequencing on the baseline gut microbiomes of these NORA patients and confirmed the results in an independent validation cohort (n=31). NMR and LC-MS were performed in ex vivo incubations to measure the capacity of each NORA microbiome to metabolize MTX. Results : Our analysis revealed significant associations between the abundance of gut bacterial taxa and future MTX response. Patients that responded to therapy had significantly lower microbial diversity (p< 0.05). A significant difference in overall gut microbial community structure was also observed between groups (Bray-Curtis distance; PERMANOVA < 0.05). At the class level, we observed statistically higher abundance of Clostridia and lower abundance of Bacteroidia in MTX-NR (p< 0.05; q< 0.2). Furthermore, the baseline metagenome separated most MTX-R from MTX-NR (PCoA; PERMANOVA p< 0.05). We identified 8 microbial modules and 23 pathways, whose abundance significantly differed between groups (p< 0.05, q< 0.2), including genes related with purine and MTX metabolism, indicating a major difference in metabolic and biosynthetic potential between the microbiome of MTX-R and MTX-NR patients. Machine learning techniques were applied to this metagenomic data, resulting in a robust model based on bacterial gene abundance that accurately predicted response to MTX in an independent cohort. Finally, MTX available levels remaining after ex vivo incubation with distal gut samples from pre-treatment RA patients significantly correlated with the magnitude of future clinical response, suggesting a direct effect of the gut microbiome on MTX bioavailability and response to therapy. Conclusion : Together, these results provide the first step towards predicting response to oral MTX in NORA patients and support the utility of the gut microbiome as a prognostic tool and perhaps even as a target for manipulation in the treatment of rheumatic and autoimmune disease

Background: There is a lack of objective diagnostic modalities that identify patients at risk for severe osteoarthritis (OA), which complicates the development of disease-modifying OA drugs. The biochemical marker, high-sensitive PRO-C2 (hsPRO-C2)¹, is a measure of the propeptide of type IIB collagen and a blood measure of cartilage formation.
Objective(s): The aim of this study was to determine whether hsPRO-C2 could predict radiographic progression in a knee OA population and stratify patients into high and low risk for joint destruction.
Method(s): Subjects with varying degrees of symptomatic knee OA (n=106) were included from a New York University (NYU) progression cohort. Radiographic progression was assessed by medial joint space narrowing (JSN), based on the change in joint space width (JSW), of the signal knee at baseline and at 24months. Baseline plasma type II collagen formation biomarker (hsPRO-C2) levels were measured. Association between baseline hsPRO-C2 and JSN was analyzed by Pearson's correlation, corrected for age, sex, BMI, race, baseline JSW, and non-steroids antiinflammatory drugs (NSAID) use. Subjects were divided into quartiles of equal size depending on the hsPRO-C2 levels, and the difference in JSN was investigated. The median level of baseline hsPRO-C2 (1.48 ng/ml) was used as a cut-off for stratifying all the subjects. The difference in JSN over 24 months was investigated in patients dichotomized based on median level. The values were compared with two-way analysis of covariates (ANCOVA).
Result(s): Baseline plasma hsPRO-C2 levels were negatively correlated with the progression of radiographic joint space narrowing over 24 months (r =-0.26, p = 0.009) after adjustment for confounders (Figure 1A). Quartile analysis demonstrated a decreasing trend of hsPRO-C2 in the radiographic progression from quartile 1 to 4 (Figure 1B). One-way ANOVA revealed a significant difference in mean JSN between quartiles 1 and 4 (0.5073 mm versus-0.0691 mm, p = 0.036, Figure 1B). JSN was significantly larger in the low hsPRO-C2 patients (0.3710 mm) com pared to the high hsPRO-C2 patients (0.0195 mm) (Figure 2).
Conclusion(s): These data suggest that symptomatic knee OA subjects with lower levels of hsPRO-C2 at baseline presented more radiographic medial JSN progression as compared to the subjects with higher levels of hsPRO-C2. The biomarker hsPRO-C2 may be useful for predicting OA progression