Barriers and facilitators to anal cancer screening among people living with HIV in Puerto Rico.

BACKGROUND: Anal cancer (AC) disproportionally affects people living with HIV (PLWH). Although there are no consensus-based AC screening guidelines, experts recommend anal pap as a primary screening tool in settings where high-resolution anoscopy (HRA) is available. We aimed to assess barriers and facilitators to anal cancer screening in a sample of Hispanic PLWH in Puerto Rico. METHODS: To assess their knowledge and attitudes, we conducted a cross-sectional survey from 2020-2021 among PLWH in Puerto Rico (n = 212). Data was collected through a telephone interview that assessed information on sociodemographics, knowledge, and attitudes about AC, and the history of AC screening. The chi-square test, Fisher exact test, and logistic regression models were used to assess factors associated with screening uptake. RESULTS: Anal Pap and HRA awareness were 60.4% and 30.7%, respectively. Anal Pap and HRA uptake was 51.5% and 19.3%, respectively. The most common barriers for anal Pap and HRA were lack of knowledge about the test and lack of physician recommendation. MSM were more likely to have heard of anal Pap (OR: 2.15, 95% CI:1.30-3.54) than MSW. MSM (OR: 3.04, 95% CI: 1.79-5.19) and women (OR: 3.00, 95% CI: 1.72-5.20) were also more likely to have undergone anal Pap. Similarly, individuals with a history of genital warts were more likely to have heard of anal Pap and HRA and have undergone anal Pap and HRA. Awareness of where to go for concerns about anal health was positively associated with having received anal Pap and HRA. CONCLUSIONS: With emerging evidence on the effectiveness of screening and treatment for anal cancer, several organizations are steering toward generating consensus-based anal cancer screening recommendations. Our study provides foundational data on barriers and facilitators to anal cancer screening in Puerto Rico that will be critical to informing screening implementation in this US territory.

Objective Bayesian Inference in Probit Models with Intrinsic Priors Using Variational Approximations.

There is not much literature on objective Bayesian analysis for binary classification problems, especially for intrinsic prior related methods. On the other hand, variational inference methods have been employed to solve classification problems using probit regression and logistic regression with normal priors. In this article, we propose to apply the variational approximation on probit regression models with intrinsic prior. We review the mean-field variational method and the procedure of developing intrinsic prior for the probit regression model. We then present our work on implementing the variational Bayesian probit regression model using intrinsic prior. Publicly available data from the world's largest peer-to-peer lending platform, LendingClub, will be used to illustrate how model output uncertainties are addressed through the framework we proposed. With LendingClub data, the target variable is the final status of a loan, either charged-off or fully paid. Investors may very well be interested in how predictive features like FICO, amount financed, income, etc. may affect the final loan status.

Prevalence of Synchronous Oligopolyposis in Incident Colorectal Cancer: A Population-Based Study.

OBJECTIVE: Colorectal cancer (CRC) is a leading causes of cancer death among men and women. The purpose of this study was to determine the prevalence of oligopolyposis (≥20 synchronous colorectal adenomas) and its associated clinicopathological characteristics in Hispanics with incident CRC. METHODS: Pathology reports from individuals diagnosed with CRC (2007 to 2011) were obtained from the PR Central Cancer Registry. Colorectal polyp burden was calculated using pathology reports and the data was normalized to colon segment size. Comparisons of demographic and clinicopathological characteristics by synchronous oligopolyposis status (<20 vs. <= *20) were performed using the chi-square or Fisher's exact test. Multivariate logistic regression models were fitted to estimate the adjusted prevalence odds ratios (aPOR), with 95% confidence intervals (CI). All analyses were performed using Stata (v.12.0). RESULTS: Analyses of 1,573 colectomy specimens was performed. Oligopolyposis was observed in 9.47% (149 of 1,573) of the subjects with incident CRC. Increasing age (aPOR50-64 = 1.72, 95% CI: 0.59-5.02; aPOR65-74 = 1.83, 95% CI: 0.64-5.27; aPOR≥75 = 2.67, 95% CI: 0.93-7.64) and proximal CRC tumor location (POR = 2.91, 95% CI:1.98-4.30) were significantly associated with having oligopolyposis at CRC diagnosis. However, subjects diagnosed with CRC at a regional stage (aPORRegional = 0.50, 95% CI: 0.32-0.79) or distant stage (aPORDistant = 0.45, 95% CI: 0.29-0.69) were less likely to have synchronous oligopolyposis (p<0.05). CONCLUSION: Our findings suggest that genetic syndromes associated with colorectal polyposis may be implicated in a higher than expected number of CRC cases. Individuals with CRC and synchronous oligopolyposis should receive genetic counseling.

Comparative Longterm Mortality Trends in Cancer vs. Ischemic Heart Disease in Puerto Rico.

OBJECTIVE: Although contemporary mortality data are important for health assessment and planning purposes, their availability lag several years. Statistical projection techniques can be employed to obtain current estimates. This study aimed to assess annual trends of mortality in Puerto Rico due to cancer and Ischemic Heart Disease (IHD), and to predict shorterm and longterm cancer and IHD mortality figures. METHODS: Age-adjusted mortality per 100,000 population projections with a 50% interval probability were calculated utilizing a Bayesian statistical approach of Age-Period-Cohort dynamic model. Multiple cause-of-death annual files for years 1994-2010 for Puerto Rico were used to calculate shortterm (2011-2012) predictions. Longterm (2013-2022) predictions were based on quinquennial data. We also calculated gender differences in rates (men-women) for each study period. RESULTS: Mortality rates for women were similar for cancer and IHD in the 1994-1998 period, but changed substantially in the projected 2018-2022 period. Cancer mortality rates declined gradually overtime, and the gender difference remained constant throughout the historical and projected trends. A consistent declining trend for IHD historical annual mortality rate was observed for both genders, with a substantial changepoint around 2004-2005 for men. The initial gender difference of 33% (80/100,00 vs. 60/100,000) in mortality rates observed between cancer and IHD in the 1994-1998 period increased to 300% (60/100,000 vs. 20/100,000) for the 2018-2022 period. CONCLUSION: The APC projection model accurately projects shortterm and longterm mortality trends for cancer and IHD in this population: The steady historical and projected cancer mortality rates contrasts with the substantial decline in IHD mortality rates, especially in men.

Optimization of synthesis and peptization steps to obtain iron oxide nanoparticles with high energy dissipation rates.

Magnetic Fluid Hyperthermia (MFH) uses heat generated by magnetic nanoparticles exposed to alternating magnetic fields to cause a temperature increase in tumors to the hyperthermia range (43-47 °C), inducing apoptotic cancer cell death. As with all cancer nanomedicines, one of the most significant challenges with MFH is achieving high nanoparticle accumulation at the tumor site. This motivates development of synthesis strategies that maximize the rate of energy dissipation of iron oxide magnetic nanoparticles, preferable due to their intrinsic biocompatibility. This has led to development of synthesis strategies that, although attractive from the point of view of chemical elegance, may not be suitable for scale-up to quantities necessary for clinical use. On the other hand, to date the aqueous co-precipitation synthesis, which readily yields gram quantities of nanoparticles, has only been reported to yield sufficiently high specific absorption rates after laborious size selective fractionation. This work focuses on improvements to the aqueous co-precipitation of iron oxide nanoparticles to increase the specific absorption rate (SAR), by optimizing synthesis conditions and the subsequent peptization step. Heating efficiencies up to 1,048 W/gFe (36.5 kA/m, 341 kHz; ILP = 2.3 nH·m2·kg-1) were obtained, which represent one of the highest values reported for iron oxide particles synthesized by co-precipitation without size-selective fractionation. Furthermore, particles reached SAR values of up to 719 W/gFe (36.5 kA/m, 341 kHz; ILP = 1.6 nH·m2·kg-1) when in a solid matrix, demonstrating they were capable of significant rates of energy dissipation even when restricted from physical rotation. Reduction in energy dissipation rate due to immobilization has been identified as an obstacle to clinical translation of MFH. Hence, particles obtained with the conditions reported here have great potential for application in nanoscale thermal cancer therapy.

Changing Statistical Significance with the Amount of Information: The Adaptive α Significance Level.

We put forward an adaptive alpha which changes with the amount of sample information. This calibration may be interpreted as a Bayes/non-Bayes compromise, and leads to statistical consistency. The calibration can also be used to produce confidence intervals whose size take in consideration the amount of observed information.

Phylogeographic evidence of cognate recognition site patterns and transformation efficiency differences in H. pylori: theory of strain dominance.

BACKGROUND: Helicobacter pylori has diverged in parallel to its human host, leading to distinct phylogeographic populations. Recent evidence suggests that in the current human mixing in Latin America, European H. pylori (hpEurope) are increasingly dominant at the expense of Amerindian haplotypes (hspAmerind). This phenomenon might occur via DNA recombination, modulated by restriction-modification systems (RMS), in which differences in cognate recognition sites (CRS) and in active methylases will determine direction and frequency of gene flow. We hypothesized that genomes from hspAmerind strains that evolved from a small founder population have lost CRS for RMS and active methylases, promoting hpEurope's DNA invasion. We determined the observed and expected frequencies of CRS for RMS in DNA from 7 H. pylori whole genomes and 110 multilocus sequences. We also measured the number of active methylases by resistance to in vitro digestion by 16 restriction enzymes of genomic DNA from 9 hpEurope and 9 hspAmerind strains, and determined the direction of DNA uptake in co-culture experiments of hspAmerind and hpEurope strains. RESULTS: Most of the CRS were underrepresented with consistency between whole genomes and multilocus sequences. Although neither the frequency of CRS nor the number of active methylases differ among the bacterial populations (average 8.6 ± 2.6), hspAmerind strains had a restriction profile distinct from that in hpEurope strains, with 15 recognition sites accounting for the differences. Amerindians strains also exhibited higher transformation rates than European strains, and were more susceptible to be subverted by larger DNA hpEurope-fragments than vice versa. CONCLUSIONS: The geographical variation in the pattern of CRS provides evidence for ancestral differences in RMS representation and function, and the transformation findings support the hypothesis of Europeanization of the Amerindian strains in Latin America via DNA recombination.

Incidence, in-hospital case-fatality rates, and management practices in Puerto Ricans hospitalized with acute myocardial infarction.

OBJECTIVE: There are extremely limited data on minority populations, especially Hispanics, describing the clinical epidemiology of acute coronary disease. The aim of this study is to examine the incidence rate of acute myocardial infarction (AMI), in-hospital case-fatality rate (CFR), and management practices among residents of greater San Juan (Puerto Rico) who were hospitalized with an initial AMI. METHODS: Our trained study staff reviewed and independently validated the medical records of patients who had been hospitalized with possible AMI at any of the twelve hospitals located in greater San Juan during calendar year 2007. RESULTS: The incidence rate (# per 100,000 population) of 1,415 patients hospitalized with AMI increased with advancing age and were significantly higher for older patients for men (198) than they were for women (134). The average age of the study population was 64 years, and women comprised 45% of the study sample. Evidence-based cardiac therapies, e.g., aspirin, beta blockers, ACE inhibitors/angiotensin receptor blockers, and statins, were used with 60% of the hospitalized patients, and women were less likely than men to have received these therapies (59% vs. 65%) or to have undergone interventional cardiac procedures (47% vs. 59%) (p<0.05). The in-hospital CFR increased with advancing age and were higher for women (8.6%) than they were for men (6.0%) (p<0.05). CONCLUSION: Efforts are needed to reduce the magnitude of AMI, enhance the use of evidence-based cardiac therapies, reduce possible gender disparities, and improve the short-term prognoses of Puerto Rican patients hospitalized with an initial AMI.

Development of a multivariable prediction model for anal high-grade squamous intraepithelial lesions in persons living with HIV in Puerto Rico: a cross-sectional study.

Background: Persons living with HIV (PLWH) are at high risk of developing anal high-grade squamous intraepithelial lesions (HSIL). We aimed to develop a prediction model for anal HSIL based on individual characteristics of PLWH. Methods: Cross-sectional study of PLWH aged ≥21 years who attended the Anal Neoplasia Clinic of the University of Puerto Rico Comprehensive Cancer Center from 2016 to 2022. The primary outcome was biopsy-confirmed anal HSIL. For each sex, relations between potential predictors and HSIL were examined using univariate (ULRM) and multivariable (MLRM) logistic regression models. Risk modelling was performed with MLRM and validated with bootstrapping techniques. The area under the ROC Curves (AUC) was estimated with 95% CI. Findings: HSIL was detected among 45.11% of patients, 68.48% were males, and 59.42% were ≥45 aged. Multivariable analysis showed that, in women, the only significant predictor for HSIL was having a previous abnormal anal cytology (p = 0.01). In men, significant predictors for HSIL were having a previous abnormal anal cytology (p < 0.001) and a history of infection with any gonorrhoea (p = 0.002). Other suggestive predictors for HSIL among women were obesity and smoking. No association between smoking and HSIL among men was observed (p < 0.05). The AUC estimated among women (0.732, 95% CI: 0.651-0.811) was higher than in men (0.689, 95% CI: 0.629-0.748). Interpretation: Our results support that the inclusion of individual characteristics into the prediction model will adequately predict the presence of HSIL in PLWH. Funding: This work was supported by the NCI (Grants #U54CA096297, #R25CA240120), the NIGMS (Grant #U54GM133807), and the NIMHD (Grant #U54MD007587).

Gender disparities in Puerto Ricans hospitalized with an initial acute myocardial infarction: A population-based perspective.

OBJECTIVE: The published literature suggests differences in presenting symptoms for acute myocardial infarction (AMI), management, and outcomes according to gender and age. However, limited information exists on this topic among Hispanics. METHODS: In Puerto Rican patients hospitalized with an initial AMI, we examined differences in presenting symptoms, effective cardiac therapies, and in-hospital mortality as a function of gender and age groups. We reviewed the medical records of patients hospitalized with a validated AMI in 12 greater San Juan, Puerto Rico hospitals during 2007. RESULTS: The average age of 1,415 patients hospitalized with a first AMI was 66 years and 45 % were women. Chest pain (81%) was the most prevalent acute presenting symptom with significant differences in its frequency between women (77%) and men (85%)(p<0.001). Right arm pain, shortness-of-breath/dyspnea, and sweating/ diaphoresis were most prevalent in patients 55-64 years old (45%), compared with patients 75 years and older (29%)(p<0.005). Relative to men and patients < 55 years old, coronary angiography/thrombolytic therapy and percutaneous coronary interventions were used less frequently in women and older patients (>75 years old). During hospitalization for AMI the in-hospital death rate was higher in women (8.6%) than men (6.0%), and increased with advancing age (p<0.05). CONCLUSION: These findings suggest significant gender and age differences in presenting symptoms, management, and early mortality in Puerto Ricans hospitalized with an initial AMI. It remains of considerable importance that health care personnel become aware of these gender and age differences to improve the management and outcomes of these patients.

Comparing Gaussian graphical models with the posterior predictive distribution and Bayesian model selection.

Gaussian graphical models are commonly used to characterize conditional (in)dependence structures (i.e., partial correlation networks) of psychological constructs. Recently attention has shifted from estimating single networks to those from various subpopulations. The focus is primarily to detect differences or demonstrate replicability. We introduce two novel Bayesian methods for comparing networks that explicitly address these aims. The first is based on the posterior predictive distribution, with a symmetric version of Kullback-Leibler divergence as the discrepancy measure, that tests differences between two (or more) multivariate normal distributions. The second approach makes use of Bayesian model comparison, with the Bayes factor, and allows for gaining evidence for invariant network structures. This overcomes limitations of current approaches in the literature that use classical hypothesis testing, where it is only possible to determine whether groups are significantly different from each other. With simulation we show the posterior predictive method is approximately calibrated under the null hypothesis (α = .05) and has more power to detect differences than alternative approaches. We then examine the necessary sample sizes for detecting invariant network structures with Bayesian hypothesis testing, in addition to how this is influenced by the choice of prior distribution. The methods are applied to posttraumatic stress disorder symptoms that were measured in 4 groups. We end by summarizing our major contribution, that is proposing 2 novel methods for comparing Gaussian graphical models (GGMs), which extends beyond the social-behavioral sciences. The methods have been implemented in the R package BGGM. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Bacterial community in the crop of the hoatzin, a neotropical folivorous flying bird.

The hoatzin is unique among known avian species because of the fermentative function of its enlarged crop. A small-bodied flying foregut fermenter is a paradox, and this bird provides an interesting model to examine how diet selection and the gut microbiota contribute to maximizing digestive efficiency. Therefore, we characterized the bacterial population in the crop of six adult hoatzins captured from the wild. A total of 1,235 16S rRNA gene sequences were grouped into 580 phylotypes (67% of the pooled species richness sampled, based on Good's coverage estimator, with C(ACE) and Chao1 estimates of 1,709 and 1,795 species-level [99% identity] operational taxonomic units, respectively). Members of 9 of the approximately 75 known phyla in Bacteria were identified in this gut habitat; the Firmicutes were dominant (67% of sequences, belonging to the classes Clostridia, Mollicutes, and Bacilli), followed by the Bacteroidetes (30%, mostly in the order Bacteroidales), Proteobacteria (1.8%), and Lentisphaerae, Verrucomicrobia, TM7, Spirochaetes, Actinobacteria, and Aminanaerobia (all <0.1%). The novelty in this ecosystem is great; 94% of the phylotypes were unclassified at the "species" level and thus likely include novel cellulolytic lineages.

Helicobacter pylori and intestinal parasites are not detrimental to the nutritional status of Amerindians.

Gastrointestinal parasites have evolved with humans and colonize many asymptomatic subjects. We investigated the influence of microbial gastrointestinal colonization on the nutritional status of rural Amerindians (40 males and 61 females). Helicobacter pylori was detected by 13C-breath test, and intestinal parasites were detected in fecal specimens. Body morphometry and bioelectrical impedance measurements were measured. Although Amerindians showed low height and weight for age, they had an adequate body mass index, morphometric parameters, and cell mass. Intestinal parasites were detected in 99% of the subjects, with no detrimental effect on nutritional parameters. Helicobacter pylori was present in 82% of adults and half the children, and was positively correlated with improved nutritional status. Despite the high prevalence of gastrointestinal microbes often associated with disease, the studied population of Amerindians had a body morphometry and composition indicative of good nutritional status, and improved in children positive for gastric H. pylori.

Walls talk: Microbial biogeography of homes spanning urbanization.

Westernization has propelled changes in urbanization and architecture, altering our exposure to the outdoor environment from that experienced during most of human evolution. These changes might affect the developmental exposure of infants to bacteria, immune development, and human microbiome diversity. Contemporary urban humans spend most of their time indoors, and little is known about the microbes associated with different designs of the built environment and their interaction with the human immune system. This study addresses the associations between architectural design and the microbial biogeography of households across a gradient of urbanization in South America. Urbanization was associated with households' increased isolation from outdoor environments, with additional indoor space isolation by walls. Microbes from house walls and floors segregate by location, and urban indoor walls contain human bacterial markers of space use. Urbanized spaces uniquely increase the content of human-associated microbes-which could increase transmission of potential pathogens-and decrease exposure to the environmental microbes with which humans have coevolved.

Burden of stroke in Puerto Rico.

Stroke is the fifth leading cause of death and the first cause of long-term disability in Puerto Rico. Trained staff reviewed and independently validated the medical records of patients who had been hospitalized with possible stroke at any of the 20 largest hospitals located in Puerto Rico during 2007, 2009, and 2011. The mean age of the 5005 newly diagnosed stroke patients (51·2% female) was 70 years. At the time of hospitalization, women were 4½ years older, were less likely to be married (60·2% vs. 39·9%, P < 0·001), smoked less (5·8% vs. 13·4%, P < 0·001), and had significantly higher proportion of diabetes (56·0% vs. 54·8%), hypertension (89·1% vs. 85·0%), and low density lipoprotein-cholesterol (LDL-Chol) > 100 mg/dL (65·7% vs. 57·5%) P < 0·05. Ischemic stroke represented 75% of all types of strokes. Atrial fibrillation was mentioned in 7·9% of the medical records. The risk for dying before discharge was similar for both genders, but was 40% higher for women than for men at one-year follow-up: age-adjusted odds ratio = 1·4 (95% confidence interval = 1·2-1·5).

Short report: socioeconomic and seasonal variations of Helicobacter pylori infection in patients in Venezuela.

Infection by Helicobacter pylori is recognized as a risk factor for gastric cancer and peptic ulcer disease. Venezuela has regions with different gastric cancer risks; the Andean region has the highest gastric cancer mortality in the country. We performed a cross-sectional study on 357 patients who underwent endoscopy attending 2 private (n = 76) and one public hospital in Caracas, Venezuela (n = 215), and one public hospital in the Andes (n = 66) to determine H. pylori infection (by a rapid biopsy urease test and histology). The proportion of infected patients in Caracas was significantly higher in public hospitals (72%) than in private hospitals (46%; P = 0.00001), and there was no significant variation the Andes and Caracas (P = 0.7001). When analyzing the data from the public hospital in Caracas, we found that the frequency of infected patients was significantly higher during the rain (96%) than during the dry months (70%, P = 0.00000001). Differences in prevalence of infection in symptomatic patients was not related to the risk of gastric cancer but to socioeconomic differences. Rain-dependent factors that may be exacerbating the clinical activity of nonulcer dyspepsia in people infected with H. pylori deserve further study.

Amerindian Helicobacter pylori strains go extinct, as european strains expand their host range.

We studied the diversity of bacteria and host in the H. pylori-human model. The human indigenous bacterium H. pylori diverged along with humans, into African, European, Asian and Amerindian groups. Of these, Amerindians have the least genetic diversity. Since niche diversity widens the sets of resources for colonizing species, we predicted that the Amerindian H. pylori strains would be the least diverse. We analyzed the multilocus sequence (7 housekeeping genes) of 131 strains: 19 cultured from Africans, 36 from Spanish, 11 from Koreans, 43 from Amerindians and 22 from South American Mestizos. We found that all strains that had been cultured from Africans were African strains (hpAfrica1), all from Spanish were European (hpEurope) and all from Koreans were hspEAsia but that Amerindians and Mestizos carried mixed strains: hspAmerind and hpEurope strains had been cultured from Amerindians and hpEurope and hpAfrica1 were cultured from Mestizos. The least genetically diverse H. pylori strains were hspAmerind. Strains hpEurope were the most diverse and showed remarkable multilocus sequence mosaicism (indicating recombination). The lower genetic structure in hpEurope strains is consistent with colonization of a diversity of hosts. If diversity is important for the success of H. pylori, then the low diversity of Amerindian strains might be linked to their apparent tendency to disappear. This suggests that Amerindian strains may lack the needed diversity to survive the diversity brought by non-Amerindian hosts.

Statistical analysis of a rhesus rotavirus vaccine trial to assess protective effect against diarrhea in Venezuelan children of 2-4 months of age

A statistical analysis of a rhesus rotavirus vaccine (RRV) trial to assess protective effect against rotavirus diarrhea was performed in venezuelan children. A total of 302 children, aged 1 to 10 months, were studied. Factors such as vaccine antigenicity, vaccination age, severity of illness, rotavirus shedding and vaccine efficacy were evaluated in order to optimize vaccine administration. An overall efficacy of 64% was found, but in the group of infants 2-4 months of age the efficacy level was the highest (92,8%). These results were supported by the higher rates of shedding an seroresponse observed in that group of infants. It was also observed that the vaccine reduces severity of diarrheal episodes