APPLICATIONS OF POINT PROCESS MODELS TO IMAGING AND BIOLOGY

This dissertation deals with point process models and their applications to imaging and messenger RNA (mRNA) transcription. We address three problems. The first problem arises in two-photon laser scanning microscopy. We model the process by which photons are counted by a detector which suffers from a dead period upon registration of a photon. In this model, we assume that there are a Poisson (α) number of excited molecules, with exponentially distributed waiting times for the emissions of photons. We derive the exact distribution of all observed counts, rather than grouped counts which were used earlier. We use it to get improved estimates of the Poisson intensity, which leads to images with higher signal-to-noise ratio. This improvement is because grouping of count data results in loss of information. We illustrate this improvement on imaging data of paper fibers. Next, we study two variants of this model: the first uses a finite time horizon and the second considers gamma waiting times for the emissions. The second problem concerns the Conway-Maxwell-Poisson distribution for count data. This family has been proposed as a generalization of the Poisson for handling overdispersion and underdisperson. Because the normalizing constant of this family is hard to compute, good approximations for it are needed. We provide a statistical approach to derive an existing approximation more simply. However, this approximation does not perform well across all the parameter ranges. Therefore, we introduce correction terms to improve its performance. For other parts of the parameter space, we use the geometric and Bernoulli distributions, with correction terms based on Taylor expansions. Using numerical examples, we show that our approximations are much better than earlier proposed methods. In the last problem, we present a new application for Conway-Maxwell-Poisson family. We use the generalized linear model setting of this family to study mRNA counts. We then compare its performance with the existing methods used for modeling mRNAs, such as the negative binomial. This empirical model can be a good modeling tool for dispersed mRNA count data when a biophysically based model is not available

Generating Functions for New Families of Combinatorial Numbers and Polynomials: Approach to Poisson–Charlier Polynomials and Probability Distribution Function

The aim of this paper is to construct generating functions for new families of combinatorial numbers and polynomials. By using these generating functions with their functional and differential equations, we not only investigate properties of these new families, but also derive many new identities, relations, derivative formulas, and combinatorial sums with the inclusion of binomials coefficients, falling factorial, the Stirling numbers, the Bell polynomials (i.e., exponential polynomials), the Poisson−Charlier polynomials, combinatorial numbers and polynomials, the Bersntein basis functions, and the probability distribution functions. Furthermore, by applying the p-adic integrals and Riemann integral, we obtain some combinatorial sums including the binomial coefficients, falling factorial, the Bernoulli numbers, the Euler numbers, the Stirling numbers, the Bell polynomials (i.e., exponential polynomials), and the Cauchy numbers (or the Bernoulli numbers of the second kind). Finally, we give some remarks and observations on our results related to some probability distributions such as the binomial distribution and the Poisson distribution

Mullerian inhibiting substance expression in papillary thyroid cancer

SummaryObjectiveTo examine the expression of Mullerian inhibiting substance (MIS) in papillary thyroid cancer.Materials and methodsThe MIS expression was examined by studying the immunohistochemistry in deparafinized sections prepared from tissue blocks of patients who were diagnosed with papillary thyroid cancer, as given in the pathology archive records (n = 23).ResultsIn all the cases studied, 50% (n = 10) showed strong staining and 50% showed moderate staining. The percentage of staining was found to be 94.2 ± 3.1% in strongly stained cases and 92.2 ± 2.1% in moderately stained cases. Normal thyroid tissues neighboring the tumor did not display any staining.ConclusionThe MIS expression can be used as a significant tool in differential diagnosis of papillary thyroid cancer and also to shed light on its etiopathogenesis

Atrial natriuretic peptide and posterior pituitary neurohormone changes in patients with acute schizophrenia

Conclusion: The obtained data indicate that the AVP level was higher, but OXT and ANP levels were lower in the patients having acute schizophrenia. Specifically OXT is related with reduced disease severity and increased functionality

On Certain Mathematical Problems in Two-Photon Laser Scanning Microscopy

In an earlier paper, we derived the distribution of the number of photons detected in two-photon laser scanning microscopy when the counter has a dead period. We assumed a Poisson number of emissions, exponential waiting times, and an infinite time horizon, and used an equivalent inhomogeneous Poisson process formulation. We then used that result to improve image quality as measured by the signal-to-noise ratio. Here, we extend that study in two directions. First, we treat the finite-horizon case to assess the accuracy of the simpler infinite-horizon approximation. Second, we use a direct approach by conditioning on the Poisson count for the infinite-horizon case to derive several polynomial identities

Disparities in ART Live Birth and Cumulative Live Birth Outcomes for Hispanic and Asian Women Compared to White Non-Hispanic Women

BACKGROUND: Conflicting disparities have been seen in assisted reproductive technology (ART) outcomes for Hispanic and Asian women compared to white, non-Hispanic (WNH) women. We, therefore, sought to clarify these disparities and calculated cumulative live birth rates (CLBR) for these racial or ethnic groups using the SARTCORS database. METHODS: We performed an analysis of the 2014–2016 SARTCORS database for member clinics doing at least 50 cycles of ART each year. RESULTS: In comparison to cycles in WNH women, cycles in Hispanic and Asian patients were in older (p < 0.001), more nulliparous women, that were less likely to have a history of endometriosis compared WNH women regardless of prior ART status. ART cycles in Hispanic and Asian women, exhibited lower rates of live birth (LB) per cycle start (p < 0.001) compared to cycles in WNH women. Multivariate logistic regression demonstrated that cycles from Hispanic and Asian women were less likely to have a LB and CLBR than white women (OR 0.86; p = 0.004, OR 0.69; p < 0.001, respectively) independent of age, parity, BMI, etiology of infertility, use of ICSI or number of embryos transferred. CONCLUSIONS: Race or ethnicity continues to be an independent prognostic factor for LB and CLBR for ART. Additional analysis of trends among Hispanic and Asian women is warranted to enable addressing disparities in outcomes in ART treatment

An approach to revealing clinically relevant subgroups across the mood spectrum

Background Individuals diagnosed with bipolar 1 disorder (BP1), bipolar 2 disorder (BP2), or major depressive disorder (MDD) experience varying levels of depressive and (hypo)manic symptoms. Clarifying symptom heterogeneity is meaningful, as even subthreshold symptoms may impact quality of life and treatment outcome. The MOODS Lifetime self-report instrument was designed to capture the full range of depressive and (hypo)manic characteristics. Methods This study applied clustering methods to 347 currently depressed adults with MDD, BP2, or BP1 to reveal naturally occurring MOODS subgroups. Subgroups were then compared on baseline clinical and demographic characteristics and as well as depressive and (hypo)manic symptoms over twenty weeks of treatment. Results Four subgroups were identified: (1) high depressive and (hypo)manic symptoms (N=77, 22%), (2) moderate depressive and (hypo)manic symptoms (N=115, 33%), (3) low depressive and moderate (hypo)manic symptoms (N=82, 24%), and (4) low depressive and (hypo)manic symptoms (N=73, 21%). Individuals in the low depressive/moderate (hypo)manic subgroup had poorer quality of life and greater depressive symptoms over the course of treatment. Individuals in the high and moderate severity subgroups had greater substance use, longer duration of illness, and greater (hypo)manic symptoms throughout treatment. Treatment outcomes were primarily driven by individuals diagnosed with MDD. Limitations The sample was drawn from three randomized clinical trials. Validation is required for this exploratory study. Conclusions After validation, these subgroups may inform classification and personalized treatment beyond categorical diagnosis

Epidemiologic Trends In Hbv Infections At A Reference Centre In Turkey: An 11-Year Retrospective Analysis

Objective. To identify changes in hepatitis B epidemiology after the implementation of the nationwide vaccination program in Turkey, hepatitis B virus (HBV) and related tests performed over a period of 11 years (2000-2010) at a reference centre were retrospectively overviewed and statistically analysed for trends. Results. Assay results for Hepatitis B surface antigen (HBsAg) and e antigen (HBeAg), Anti-HBs, Anti-HBe, Anti-HBc immunoglobulins and HBV DNA as well as aspartate aminotransferase (AST), alanine aminotransferase (ALT), gama-glutamyl transpeptidase (GGT) and alkaline phosphatase (AP) levels, obtained via standardized commercial assays were included in the analysis. Overall, a stable anti-HBs incidence (43.6%) and male predominance in infected individuals were noted. Total Anti-HBc was detected in 43.3% of the Anti-HBs reactive population, demonstrating that the immunity against HBV has still been acquired through virus exposure. An intermediate HBsAg seroprevalence of 6.0% was observed with a significant decrease from 12.3% to 5.0% from 2000 to 2010. Anti-HBe positive infections were more frequent than those with HBe antigenemia (77.1% vs. 18.5%) with a notable increase from 2000 to 2003. HBV DNA was detected in 23.6-25.6% with serological markers of viral replication and was more prevalent in HBeAg positive individuals in parallel with AST, ALT and GGT levels. Evidence for horizontal transfer as the major transmission route was revealed with a reduction of childhood HBV infections, attributable to the ongoing vaccination efforts

Mullerian inhibiting substance expression in papillary thyroid cancer

To examine the expression of Mullerian inhibiting substance (MIS) in papillary thyroid cancer. The MIS expression was examined by studying the immunohistochemistry in deparafinized sections prepared from tissue blocks of patients who were diagnosed with papillary thyroid cancer, as given in the pathology archive records (n = 23). In all the cases studied, 50% (n = 10) showed strong staining and 50% showed moderate staining. The percentage of staining was found to be 94.2 ± 3.1% in strongly stained cases and 92.2 ± 2.1% in moderately stained cases. Normal thyroid tissues neighboring the tumor did not display any staining. The MIS expression can be used as a significant tool in differential diagnosis of papillary thyroid cancer and also to shed light on its etiopathogenesis