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Meta-analyses from 2018–2022 have shown that obesity increases the risk of various cancers such as acute myeloid lymphoma, chronic myeloid lymphoma, diffuse beta cell lymphoma, Hodgkin's lymphoma, leukemia, multiple myeloma, non-Hodgkin's lymphoma, bladder, breast, cholangiocarcinoma, colorectal, ovarian, esophageal, kidney, liver, prostate, thyroid, and uterus. Contextually, obesity, and its comorbidities, is the largest, most lethal pandemics in the history of mankind; hence, identification of underlying mechanisms is needed to adequately address this global health threat. Herein, we present the metabolic and hormonal mechanisms linked to obesity that might etiologically contribute to neoplasia, including hyperinsulinemia and putative places in the insulin-signaling pathway. Excess insulin, acting as a growth factor, might contribute to tumorigenesis, while abundant ATP and GDP supply the additional energy needed for proliferation of rapidly dividing cells. Our observations in the Ecuadorian cohort of subjects with Laron syndrome (ELS) prove that obesity does not always associate with increased cancer risk. Indeed, despite excess body fat from birth to death, these individuals display a diminished incidence of cancer when compared to their age- and sex-matched relatives. Furthermore, in cell cultures exposed to potent oxidizing agents, addition of ELS serum induces less DNA damage as well as increased apoptosis. ELS individuals have absent growth hormone (GH) counter-regulatory effects in carbohydrate metabolism due to a defective GH receptor. The corresponding biochemical phenotype includes extremely low basal serum concentrations of insulin and insulin-like growth factor-I, lower basal glucose and triglyceride (TG) levels, and diminished glucose, TG, and insulin responses to orally administered glucose or to a mixed meal.

Background Radioiodine (RAI) therapy is an important adjuvant therapy for differentiated thyroid carcinoma (DTC) patients. Several studies have demonstrated the efficacy of RAI in reducing the risk of thyroid cancer recurrence and mortality; however, the ideal timing to initiate RAI after surgery is debatable. This systematic review and meta-analysis evaluates the risk of achieving excellent response and mortality when comparing late administration versus early administration of RAI in patients with DTC. Methods We searched Medline, Embase, Scopus, and Cochrane Database from inception to April 2021 to identify experimental and observational studies that evaluated the impact of different timings of RAI after surgery (3 months, 6 months, 9 months) on the risk of excellent response and thyroid-specific mortality in DTC patients with low, intermediate, and high risk of recurrence. We used random-effects model to pool dichotomous variables with odd ratios (OR) and their confidence intervals (95%CI). The risk of bias was evaluated using the Newcastle Ottawa Scale. PROSPERO Protocol ID CRD42021267036. Results We included 12 retrospective cohort studies with 34,833 patients. The majority of participants were female (78.00%) and the mean age ranged from 39.70 (± 3.40) to 51.60 (± 1.70) years. In patients with low-to-intermediate risk of recurrence, there were no differences in excellent response (OR 0.76, 95%CI: 0.34-1.68, I2: 78.00%, n=1099) and mortality risk (OR 1.00, 95%CI: 0.84-1.19, I2: 0.00%, n=21450) in the late group (>3 months) compared to the early group (3 months) when compared to the early group (6 months) when compared to the early group ( Conclusions Low-to-moderate quality of evidence suggests increased mortality with delayed RAI (>6 months) in DTC patients with high risk of recurrence. The timing of RAI for other risk categories has little or no effect. Further experimental studies are needed to confirm these results and draw robust conclusions. Presentation: Saturday, June 11, 2022 1:00 p.m. - 3:00 p.m.

Transgender adolescents may require for inpatient psychiatric care, and have unique healthcare needs and can face barriers to quality care. This study sought to address limited understanding of the inpatient experience of transgender adolescents. This study uses qualitative methods to gain insight into the experience of transgender adolescents and psychiatric care providers on an adolescent inpatient psychiatric unit in the northeast United States. Semi-structured interviews were conducted with patients (9 total, ages 13–17) and unit care providers (18 total). These interviews were recorded, transcribed, and analyzed using inductive thematic analysis. Patients and providers generally reported a supportive inpatient environment. Factors that contributed to this environment were efforts by care providers to respect patients regardless of gender identity, to use patient’s preferred identifiers, and to acknowledge mistakes in identifier use. Barriers to consistently supportive interactions were also identified, including a lack of consistent identification of a patient’s transgender identity in a supportive manner during the admission intake, challenges associated with the presence of birth-assigned name and gender within the care system (e.g. in the electronic medical record, identifying wristbands, attendance rosters), and a lack of formal training of care providers in transgender cultural competency. Interviews also provided insight into how providers grapple with understanding the complexities of gender identity. Findings suggest that gender-affirming approaches by providers are experienced as supportive and respectful by transgender adolescent patients, while also identifying barriers to consistently supportive interactions that can be addressed to optimize care.

The frequency of thyroid surgeries has increased proportionality to the increment incidence of thyroid cancer. Yet, the number of experienced thyroid surgeons has not raised accordingly to that of thyroid cancer incidence. As a result, many thyroid surgeries are conducted by low volume surgeons that might affect the risk of surgical complications and remaining postoperative thyroid tissue. These poor surgical outcomes might be higher among countries affected by more thyroid cancer diagnosis yet with limited thyroid surgical expertise such as in a resource limited setting as Ecuador. The purpose of this study is to assess the outcomes of thyroid cancer surgery in a referral thyroid cancer center in Ecuador, and to explore the risk factors associated with poor surgical outcomes. Methods Around 344 patients with non-metastatic differentiated thyroid undergoing initial thyroid surgery (total thyroidectomy, central neck dissection) for a primary tumor were identified from an institutional database, and treated between June 1st, 2014 to December 31st, 2017. Poor surgical outcome was described in patients experience any surgical complications (recurrent laryngeal injury assessed with laryngoscopy and postoperative temporary and permanent hypoparathyroidism) or a stimulated post-operative Tg> 2mg/dL. Results Of the 344 patients, 127 patients had surgical complication and post-operative stimulated Tg data available to analyze. From this cohort, 22 (17%) patients had surgical complications, 19 (15%) hypoparathyroidism ( 8% temporary and 7% permanent) and 5 (4%) recurrent laryngeal nerve injury. A total of 74 (58%) out of 127 patients had a sTg value higher than 2 ng/ml. A poor surgical outcome was present in 88 (64%) patients. The multivariate analysis showed that the factor that was independently associated with poor surgical outcome was tumor size ≥1cm (OR: 3.3, 95% CI 1.18 - 9.3). Sex, age at diagnosis, benign non-nodular thyroid disease, BMI, place of surgery, tumor focallity, histology, extra thyroid extension variables were not- associated with poor surgical outcomes. Conclusion Two thirds of thyroid cancer surgeries, assessed in an Ecuadorian thyroid cancer referral center, had a poor surgical outcome that may lead to low patient’s low quality of life, and the need for additional treatment strategies. These estimates are higher than what is reported from the literature and suggest that the overdiagnosis of thyroid cancer in non-high-income country income countries might result in worse surgical outcomes.

The turnaround times for conventional methods used to detect Mycobacterium tuberculosis in sputum samples and to obtain drug susceptibility information are long in many developing countries, including Panama, leading to delays in appropriate treatment initiation and continued transmission in the community. We evaluated the performance of a molecular line probe assay, the Genotype MTBDR plus version 2.0 assay, in detecting M. tuberculosis complex directly in respiratory specimens from smear-positive tuberculosis cases from four different regions in Panama, as well as the most frequent mutations in genes conferring resistance to isoniazid ( katG and inhA ) and rifampin ( rpoB ). Our results were confirmed with the nitrate reductase assay and genomic sequencing. M. tuberculosis complex was detected by the Genotype MTBDR plus 2.0 assay with 100% sensitivity and specificity. The sensitivity and specificity for rifampin resistance were 100% and 100%, respectively, and those for isoniazid resistance were 90.7% and 100%. Isoniazid monoresistance was detected in 5.2% of new cases. Genotype MTBDR plus 2.0 is highly accurate in detecting M. tuberculosis complex in respiratory specimens and is able to discriminate isoniazid-monoresistant cases from multidrug-resistant cases within 2 days.

Processing large graph datasets represents an increasingly important area in computing research and applications. The size of many graph datasets has increased well beyond the processing capacity of a single computing node, thereby necessitating distributed approaches. As these datasets are processed over a distributed system of nodes, this leads to an inter-node communication cost problem that negatively affects system performance. Previously proposed algorithms implemented breadth-first search (BFS) for graph searching and focused on the execution, parallel performance and not the communication. In this paper a new methodology is proposed that combines BFS with random selection in order to partition large graph datasets and effectively minimize inter-node communication. The new method is discussed and applied to the single-source shortest path and PageRank algorithms using three graphs that are representative of real-world scenarios. Experimental results show that graph inter-node communication for canonical graphs representative of real-world data is improved up to 42 % in case of Powerlaw graph, up to 27 % in case of Random near K-regular graph (with low degree), and up to 7 % in case of Random near K-regular graph (with high degree).

An efficient MapReduce Algorithm for performing Similarity Joins between multisets is proposed. Filtering techniques for similarity joins minimize the number of pairs of entities joined and hence improve the efficiency of the algorithm. Multisets represent real-world data better by considering the frequency of its elements. Prior serial algorithms incorporate filtering techniques only for sets, but not multisets, while prior MapReduce algorithms do not incorporate any filtering technique or inefficiently and unscalably incorporate prefix filtering. This work extends the filtering techniques, namely the prefix, size and positional to multisets, and also achieves the challenging task of efficiently incorporating them in the shared-nothing MapReduce model, thereby minimizing the pairs generated and joined, resulting in I/O, network and computational efficiency. A technique to enhance the scalability of the algorithm is also presented as a contingency need. Algorithms are developed using Hadoop and tested using real-world Twitter data. Experimental results demonstrate unprecedented performance gain.

Radon-222 and its parent, radium-226, is a naturally occurring radioactive decay product of uranium-238. The US Environmental Protection Agency (USEPA) states that 10% of total lung cancer cases in the United States are directly attributable to indoor radon. The USEPA has categorized Ohio as a Zone 1 state (i.e., the average indoor radon screening level is greater than 4 pCi/L). To implement preventive measures, it is necessary to know radon concentration levels in all the zip codes of a geographic area. However, it is not possible to survey all the zip codes, owing to reasons such as inapproachability. In such places where radon data are unavailable, several interpolation techniques are used to estimate the radon concentrations. This article presents a comparison between recently developed interpolation techniques such as neural network techniques, support vector regression (SVR), random forest regression (RFR), and the conventional interpolation techniques. The performance of all the techniques has been assessed using 10-fold cross-validation data. This study confirmed that the correction-based artificial neural networks have performed better over SVR and RFR with least validation error of 3.63. © 2014 American Institute of Chemical Engineers Environ Prog, 34: 169–177, 2015

Background There is scant data on young children receiving protease inhibitor-based therapy in real-life resource-limited settings and on the optimal timing of therapy among children who survive infancy. Our aim was to evaluate outcomes at the Hospital del Nino, Panama, where children have been routinely treated with lopinavir/ritonavir (LPV/r)-based therapy since 2002. Methods Retrospective cohort analysis of all HIV-infected children enrolled in care between January 1, 1991, and June 1, 2011. Kaplan-Meier method and Cox proportional hazards regression were used to evaluate death, virologic suppression and virologic rebound. Results Of 399 children contributing 1944 person-years of follow-up, 254 (63.7%) were treated with LPV/r and 94 (23.6%) were never treated with antiretrovirals (ARVs). Among infants, improved survival was associated with male gender (hazard rate of death[HRdeath] 0.54, 95% confidence interval [CI]: 0.32-0.92) and treatment with highly active antiretroviral therapy (HRdeath 0.32, 95% CI: 0.12-0.83), whereas residence outside of Panama City was associated with poorer survival (HRdeath 1.72, 95% CI: 1.01-2.94). Among children who survived to 1 year of age without exposure to ARVs, LPV/r-based therapy improved survival (HRdeath 0.07, 95% CI: 0.01-0.33). Virologic suppression was achieved in 42.1%, 70.5% and 85.1% by 12, 24 and 60 months of follow-up among children treated with LPV/r. Virologic suppression was not associated with prior ARV exposure or age at initiation of therapy but was associated with residence outside of Panama City (HR suppression 1.93, 95% CI: 1.19-3.14). Patients with a baseline viral load >100,000 copies/mL were less likely to achieve suppression (HR suppression 0.37, 95% CI: 0.21-0.66). No children who achieved virologic suppression after initiating LPV/r died. Conclusions LPV/r-based therapy improved survival not only in infants but also in children over 1 year of age. Age at initiation of LPV/r-based therapy or prior ARVs did not impact virologic outcomes.

The Gnutella file sharing system allows a large number of peers to share their local files. However, it does not coordinate the way by which these shared objects are named or how they are searched by other users; such decisions are made independently by each peer. In this work, we investigate the practical performance implications of this design. We collected the shared filenames and user generated queries over a three-year period. We show the mismatch between these naming mechanisms. We show the fundamental limitations of Gnutella performance that cannot be addressed by improvements in overlays or by varying the search mechanisms alone. Based on our observations, we describe two practical approaches to improve Gnutella performance. We describe a mechanism to build the file term synopsis using the observed popularity of queries routed through the ultrapeer. We also describe a query transformation mechanism that improves the success rates for failed queries.

Introduction La denervation articulaire constitue une alternative aux arthroplasties prothetiques et aux arthrodeses dans les arthropathies douloureuses avec des mobilites en partie preservees. L’objectif est d’evaluer nos resultats avec comme hypothese que la denervation de l’interphalangienne proximale (IPP) est une intervention efficace avec un benefice durable. Patients et methode Vingt-cinq denervations ont ete realisees chez 21 patients, 20 femmes et 1 homme, de 63 ans (44–77) d’âge moyen. Les rayons traites etaient 4 index, 16 majeurs, 3 annulaires et 2 auriculaires. L’origine etait une arthrose idiopathique dans 19 cas, une arthrose post-traumatique dans 2 cas et une arthropathie inflammatoire dans 4 cas. L’EVA moyenne etait de 7,5 (5–10). Le retentissement etait modere dans 2 cas, important dans 17 et majeur dans 6. Sur les radiographies, l’atteinte articulaire etait moderee 13 fois et importante 12 fois. L’intervention a ete realisee 2 fois par voie palmaire, 11 fois par 2 voies laterales et 12 fois par voie dorsale. Resultats Il n’y a pas eu de complication immediate ni de troubles de la sensibilite pulpaire. Trois AD ont ete diagnostiquees : 2 moderees et une plus severe. Dans 1 cas, les douleurs n’ont pas ete modifiees par l’intervention et le patient a ete traite secondairement par prothese avec un bon resultat. Les 20 patients restants (24 doigts) ont ete evalues avec un recul moyen de 43 mois (de 3,5 a 148) par un examinateur independant. L’EVA moyenne a la revision etait de 1,1 (0–5) et ≤ 2 dans 22 des 24 cas. La mobilite etait diminuee 2 fois, identique 12 fois et amelioree dans 10 cas. La satisfaction moyenne etait de 8,7/10 (de 5 a 10). Discussion Le seul echec vrai sur 25 cas est survenu d’emblee. Les 24 autres cas ont tous ete ameliores et il n’y a pas eu de deterioration secondaire du resultat sur la douleur. Foucher et al. (1998) rapportent 15 % d’echecs mais ils realisaient uniquement une section des branches provenant des nerfs collateraux digitaux palmaires. Avec 4 % d’echecs, cette serie retrouve des resultats comparables voire meilleurs, peut-etre dus a la section associee des branches nerveuses d’origine dorsale. Conclusion Intervention efficace sur la douleur, avec un benefice qui reste stable dans le temps, elle doit faire partie de l’arsenal therapeutique au meme titre que les arthroplasties prothetiques et l’arthrodese.

The incidence of people with motor disabilities in Colombia is around 6.4%, which is a major social problem, because people with such disabilities lose their autonomy to perform basic actions such as displacement. Therefore, we propose a solution to the problem of mobility in people with motor disabilities, allowing to take control of the engines, with a voice comand recognition system. This paper presents a methodology for recognition of isolated spanish words (silla, atras, adelante, derecha, izquierda, pare). To this end, we use a methodology based on the wavelet transform preprocessing. The characterization of the filtered signal is performed by Mel Cepstral Coefficients and classification stage using hidden Markov models. The methodology has proven to be robust, because the databases used for training the system have been acquired in noisy environments as well as controlled, presenting performances in classification acuracy of 98%.

Gnutella peers independently choose the way in which objects are named as well as queried. Using a long term analysis of the files shared and queries issued, we show that this flexibility leads to a mismatch between the way that objects were named and the way that users were issuing search queries. Thirty percent of the failed queries contained keywords that were not present in any file name while the remaining queries failed because no file name contained all the keywords in a particular query. Our earlier analysis of files shared in the popular iTunes music file sharing system showed that standardizing the file names to make them easier to search is not a viable alternative. Instead, we transform the queries to better match the objects available in the system. We investigated spell correction (using file name information from the neighborhood) as well as remove query keywords. We consider the results from the transformed query to be relevant to the intent of the original query if the transformed query used many of the original keywords and the number of matching files closely matched the number of matches for typical successful queries. Our approach is practical and uses information available within the immediate neighborhood of an ultra-peer. An overlay agnostic analysis shows that our transformation improves success rates from 45% to between 72.5% and 91.2%. Using our Hybrid mechanism as a Gnutella middleware, our transformation produced relevant results for about 61% of the failed queries.

Modern P2P systems use hybrid searches to improve search efficiency. They use a synopsis of neighborhood content to determine whether to use a structured or unstructured overlay to satisfy a particular query. Because of their size restrictions, a synopsis cannot hold all the terms from every file in the neighborhood. The challenge is to choose the terms that should be represented in the synopsis. In this work, we investigated the distribution of query terms and file terms in Gnutella networks. We observed that there was a mismatch between terms that were popular among file names and the terms that were popular among the queries generated by the user. Because the query behavior changed with time, a synopsis based on only static set of popular file terms was ill-suited to support efficient searches. We used these observations to design a synopsis creation algorithm that dynamically adapted to the query workload and selected terms for the synopsis to reflect popular terms in both the query workload and file distribution. Our preliminary experimental analysis showed that our Query-Adaptive synopsis improved the search performance over the traditional file-based synopsis model.

Hybrid P2P systems rely on the assumption that sufficient objects exist nearby in order to make the unstructured search component efficient. This availability depends on the object annotations as well as on the terms in the queries. Earlier work assumed that the object annotations and query terms follow Zipf-like long-tail distribution. We show that the queries in real systems exhibit more complex temporal behavior. To support our position, first we analyzed the names and annotations of objects that were stored in two popular P2P sharing systems; Gnutella and Apple iTunes. We showed that the names and annotations exhibited a Zipf like long tail distribution. The long tail meant that over 98% of the objects were insufficiently replicated (less than 0.1% of the peers). We also analyzed a query trace of the Gnutella network and identified the popularity distribution of the terms used in the queries. We showed that the set of popular query terms remained stable over time and exhibited a similarity of over 90%. We also showed that despite the Zipf popularity distributions of both query terms and file annotation terms, there was little similarity over time (

A number of prior efforts analyzed the behavior of popular peer-to-peer (P2P) systems and proposed ways for maintaining the overlays as well as methods for searching for contents using these overlays. However, little was known about how successful users could be in locating the shared objects in these system. There might be a mismatch between the way content creators named objects and the way such objects were queried by the consumers. Our aim was to examine the terms used in the queries and shared object names in the Gnutella file-sharing system. We analyzed the object names of over 20 million objects collected from 40,000 peers as well as terms from over 230,000 queries. We observed that almost half (44.4%) of the queries had no matching objects in the system regardless of the overlay or search mechanism used to locate the objects. We also evaluated the query success rates against random peer groups of various sizes (200, 1K, 2K, 3K, 4K, 5K, 10K and 20K peers sampled from the full 40,000 peers). We showed that the success rates increased rapidly from 200 to 5,000 peers, but only exhibited modest improvements when increasing the number of peers beyond 5,000. Finally, we observed Zipf-like distribution for query terms and the object names. However, the relative popularity of a term in the object names did not correlate with the terms popularity in the query workload. This observation affected the ability of hybrid P2P systems to guide searches by creating a synopsis of the peer object names. A synopsis created by using the distribution of terms in the object names need not represent relevant terms for the query. Our results can be used to guide the design of future P2P systems that are optimized for the observed object names and user query behavior.

Peer-to-Peer (P2P) applications, such as Gnutella, are evolving to address some of the observed performance issues. In this paper, we analyze Gnutella behavior in 2003, 2005, and 2006. During this time, the protocol evolved from v0.4 to v0.6 to address problems with overhead of overlay maintenance and query traffic bandwidth. The goal of this paper is to understand whether the newer protocols address the prior concerns. We observe that the new architecture alleviated the bandwidth consumption for low capacity peers while increasing the bandwidth consumption at high capacity peers. We measured a decrease in incoming query rate. However, highly connected ultra-peers must maintain many connections to which they forward all queries thereby increasing the outgoing query traffic. We also show that these changes have not significantly improved search performance. The effective success rate experienced at a forwarding peer has only increased from 3.5% to 6.9%. Over 90% of queries forwarded by a peer do not result in any query hits. With an average query size of over 100 bytes and 30 neighbors for an ultra-peer, this results in almost 1 GB of wasted bandwidth in a 24 hour session. We outline solution approaches to solve this problem and make P2P systems viable for a diverse range of applications.