Tag: pubmed

Neural Comput. 2022 Oct 14:1-35. doi: 10.1162/neco_a_01549. Online ahead of print.

ABSTRACT

Domain adaptation aims to transfer knowledge of labeled instances obtained from a source domain to a target domain to fill the gap between the domains. Most domain adaptation methods assume that the source and target domains have the same dimensionality. Methods that are applicable when the number of features is different in each domain have rarely been studied, especially when no label information is given for the test data obtained from the target domain. In this letter, it is assumed that common features exist in both domains and that extra (new additional) features are observed in the target domain; hence, the dimensionality of the target domain is higher than that of the source domain. To leverage the homogeneity of the common features, the adaptation between these source and target domains is formulated as an optimal transport (OT) problem. In addition, a learning bound in the target domain for the proposed OT-based method is derived. The proposed algorithm is validated using both simulated and real-world data.

PMID:36283052 | DOI:10.1162/neco_a_01549

Neural Comput. 2022 Oct 14:1-14. doi: 10.1162/neco_a_01543. Online ahead of print.

ABSTRACT

Our neurons seem capable of handling any type of data, regardless of its scale or statistical properties. In this letter, we suggest that optimal coding may occur at the single-neuron level without requiring memory, adaptation, or evolutionary-driven fit to the stimuli. We refer to a neural circuit as optimal if it maximizes the mutual information between its inputs and outputs. We show that often encountered differentiator neurons, or neurons that respond mainly to changes in the input, are capable of using all their information capacity when handling samples of any statistical distribution. We demonstrate this optimality using both analytical methods and simulations. In addition to demonstrating the simplicity and elegance of neural processing, this result might provide a way to improve the handling of data by artificial neural networks.

PMID:36283043 | DOI:10.1162/neco_a_01543

Neural Comput. 2022 Oct 14:1-27. doi: 10.1162/neco_a_01544. Online ahead of print.

ABSTRACT

Complex systems can be defined by “sloppy” dimensions, meaning that their behavior is unmodified by large changes to specific parameter combinations, and “stiff” dimensions, whose change results in considerable behavioral modification. In the neocortex, sloppiness in synaptic architectures would be crucial to allow for the maintenance of asynchronous irregular spiking dynamics with low firing rates despite a diversity of inputs, states, and short- and long-term plasticity. Using simulations on neural networks with first-order spiking statistics matched to firing in murine visual cortex while varying connectivity parameters, we determined the stiff and sloppy parameters of synaptic architectures across three classes of input (brief, continuous, and cyclical). Algorithmically generated connectivity parameter values drawn from a large portion of the parameter space reveal that specific combinations of excitatory and inhibitory connectivity are stiff and that all other architectural details are sloppy. Stiff dimensions are consistent across input classes with self-sustaining synaptic architectures following brief input occupying a smaller subspace as compared to the other input classes. Experimentally estimated connectivity probabilities from mouse visual cortex are consistent with the connectivity correlations found and fall in the same region of the parameter space as architectures identified algorithmically. This suggests that simple statistical descriptions of spiking dynamics are a sufficient and parsimonious description of neocortical activity when examining structure-function relationships at the mesoscopic scale. Additionally, coarsegraining cell types does not prevent the generation of accurate, informative, and interpretable models underlying simple spiking activity. This unbiased investigation provides further evidence of the importance of the interrelationship of excitatory and inhibitory connectivity to establish and maintain stable spiking dynamical regimes in the neocortex.

PMID:36283042 | DOI:10.1162/neco_a_01544

Rev Med Inst Mex Seguro Soc. 2022 Oct 25;60(6):657-665.

ABSTRACT

OBJECTIVE: Identify risk factors for severe outcome in Mexican patients with COVID-19 in the population of Quintana Roo.

MATERIAL AND METHODS: Study of 5,916 who met the criteria for suspected cases of COVID-19, 2,531 confirmed by qrTPCR-Sars-CoV-2 tests, of which 1,486 were positive, among which they were classified as hospitalized (severe COVID-19) and outpatients. Multivariate logistic regression analysis was performed to explore the factors associated with the severity of COVID-19 and death as clinical outcomes. The basic reproduction number (R0) was calculated Statistical analysis) Endorsement of the ethics committee 2301.

RESULTS: SARS-CoV-2 positive patients presented a high prevalence of hypertension 29.1%, diabetes 23.5%, obesity 24%, and 48.5% have at least one chronic disease. There is a high risk of severity for COVID-19 in patients with diabetes OR=3.14, hypertension OR=1.88, obesity OR=1.68, kidney disease OR=3.2, older than 65 years OR=13.6 and men OR=1.7. These factors also increase the risk of death up to 7.7 times. The maximum R0 during the epidemic was 2.4.

CONCLUSION: Liver and kidney disease, diabetes, hypertension, and obesity are significantly associated with severe COVID-19 and death.

PMID:36283034

Res Number Theory. 2022;8(4):70. doi: 10.1007/s40993-022-00373-2. Epub 2022 Sep 16.

ABSTRACT

We consider spaces of modular forms attached to definite orthogonal groups of low even rank and nontrivial level, equipped with Hecke operators defined by Kneser neighbours. After reviewing algorithms to compute with these spaces, we investigate endoscopy using theta series and a theorem of Rallis. Along the way, we exhibit many examples and pose several conjectures. As a first application, we express counts of Kneser neighbours in terms of coefficients of classical or Siegel modular forms, complementing work of Chenevier-Lannes. As a second application, we prove new instances of Eisenstein congruences of Ramanujan and Kurokawa-Mizumoto type.

PMID:36283022 | PMC:PMC9583295 | DOI:10.1007/s40993-022-00373-2

Pol Merkur Lekarski. 2022 Oct 21;50(299):282-286.

ABSTRACT

Myocardial infarction (MI) of the right ventricle (RV) coexists in 20- 60% of patients with inferior MI. There are electrocardiographic indicators which are connected with RV MI, which may also predict unfavorable clinical outcome of in-hospital follow-up.

AIM: The aim of the study was determination a value of seven electrocardiographic predictors of RV MI in prognosis of in-hospital complications in patients with inferior MI.

MATERIALS AND METHODS: The analysis of hospital files of patients admitted with diagnosis of inferior MI with persistent ST elevation (STEMI) was retrospectively performed. A set of seven RV MI predictors (RVMIP) was assessed from the electrocardiographic tracings (ECG). Finally in group of 167 patients relation between each RVMIP and in-hospital complications was statistically evaluated.

RESULTS: The most often RVMIP was an elevation of ST higher in III lead then in II and aVF (RVMIP-2; recorded in 61,7% patients). In total any RVMIP was found in ECG of 142 patients (85%). Patients who had more RVMIP were more prone for combined adverse cardiac event (CACE, which included artificial respirotherapy, lungs edema and cardiogenic shock) (p=0,012); ventricular arrhythmias (p<0,001) and second/third grade atrioventricular blocks (p=0,028). Advanced atrioventricular blocks were more often observed in patient with ST elevation in V1 and ST depression in aVL (OR=4,91, p=0,005; OR=4,67, p=0,006; respectively). On the other hand second/third grade atrioventricular blocks were also related to higher incidence of CACE, ventricular arrhythmias and atrial fibrillation (AF), respectively: OR=8,1, p<0,001; OR=7,19, p=0,001; OR=5,75, p=0,001).

CONCLUSIONS: The more RVMIPs the higher risk of in-hospital complication in patients with inferior MI. The second/third grade atrioventricular blocks were recorded more often in patients with ST elevation in V1 and ST depression in aVL. Advanced atrioventricular conduction blocks were related to worse outcome of in-hospital followup. A detailed ECG analysis in admission still adds important contribution in determination of in-hospital risk of complications.

PMID:36283009

Multimodal Learn Clin Decis Support (2021). 2021 Oct;13050:1-11. doi: 10.1007/978-3-030-89847-2_1. Epub 2021 Oct 20.

ABSTRACT

Advances in neuroimaging have yielded extensive variety in the scale and type of data available. Effective integration of such data promises deeper understanding of anatomy and disease-with consequences for both diagnosis and treatment. Often catered to particular datatypes or scales, current computational tools and mathematical frameworks remain inadequate for simultaneously registering these multiple modes of “images” and statistically analyzing the ensuing menagerie of data. Here, we present (1) a registration algorithm using a “scattering transform” to align high and low resolution images and (2) a varifold-based modeling framework to compute 3D spatial statistics of multiscale data. We use our methods to quantify microscopic tau pathology across macroscopic 3D regions of the medial temporal lobe to address a major challenge in the diagnosis of Alzheimer’s Disease-the reliance on invasive methods to detect microscopic pathology.

PMID:36283001 | PMC:PMC9582035 | DOI:10.1007/978-3-030-89847-2_1

Rev Med Inst Mex Seguro Soc. 2022 Oct 25;60(6):640-648.

ABSTRACT

BACKGROUND: Acute respiratory distress syndrome, due to SARS-CoV-2, is a worldwide health problem. The neutrophil-lymphocyte index allows risk stratification in patients with severe and poor prognostic data, since it reflects the inflammatory state.

OBJECTIVE: To determine whether the Neutrophil-Lymphocyte Index delta predicts mortality in patients with COVID-19.

MATERIAL AND METHODS: We conducted a longitudinal, comparative study in patients with COVID-19, older than 18 years, admitted to the ICU. We evaluated HAS, DM, obesity, COPD, asthma, PaO2/FiO2, tomographic severity. On admission and on days 3 and 7 we measured Neutrophil-Lymphocyte Index, SOFA and APACHE score. For statistical analysis, we performed ROC and Kaplan-Meyer curves.

RESULTS: We included 180 patients with COVID-19, 63 died (35%). Delta INL1(Day1-day3)>4.11 was associated with mortality (AUC:0.633); sensitivity 55.56% and specificity 77.78%, CI95 0.55-0.70, for delta INL2 (Day1-day7)>8.95 (AUC:0.623); sensitivity 44.44% and specificity 84.62%, CI95 0.54-0.69. Difference in survival was observed for Delta1. SOFA scale >6, was associated with more days of mechanical ventilation and lower PaO2/FiO2 (p<0.001).

CONCLUSIONS: INL delta between the day of ICU admission and the 3rd day of evolution is a predictor of mortality in critically ill patients.

PMID:36282995

J Low Genit Tract Dis. 2022 Oct 24. doi: 10.1097/LGT.0000000000000712. Online ahead of print.

ABSTRACT

OBJECTIVES: Small cell carcinoma of the vagina (SmCCV) is an extremely rare disease. Evidence-based data and specific guidelines are lacking. We conducted the first systematic review of case reports to provide the most overall picture of SmCCV.

MATERIALS AND METHODS: Literature search in PubMed and Scopus was performed using the terms “small cell carcinoma” and “vagina.” English-language case reports of primary SmCCV up to January 2022 were included.

RESULTS: Twenty-nine articles describing 44 cases met our inclusion criteria. We report a new case of our hospital. The global median overall survival (mOS) was 12.00 months (95% CI = 9.31-14.69). The mOS was not reached for stage I, and it was 12.00, 12.00, 9.00, and 8.00 months for stages II, III, IVA, and IVB, respectively (statistically significant differences between stage I and stages II, III, or IVA [log rank p = .003-.017]). Thirty-five cases received local treatments (77.8%). The mOS of patients treated with surgery ± complementary chemotherapy, radiotherapy ± complementary chemotherapy, chemoradiation ± complementary chemotherapy, and surgery + radiotherapy ± complementary chemotherapy were 11.00, 12.00, 17.00, and 29.00 months, respectively. The use of adjuvant or neoadjuvant chemotherapy (64.5%, mostly platinum + etoposide) showed longer mOS (77.00 vs 15.00 months). Four of 5 tested cases presented human papillomavirus infection, 3 of them presenting type 18.

CONCLUSIONS: Small cell carcinoma of the vagina shows dismal prognosis. Multimodal local management plus complementary chemotherapy seems to achieve better outcomes. Human papillomavirus could be related to the development of SmCCV. A diagnostic-therapeutic algorithm is proposed.

PMID:36282979 | DOI:10.1097/LGT.0000000000000712

J Crohns Colitis. 2022 Oct 25:jjac146. doi: 10.1093/ecco-jcc/jjac146. Online ahead of print.

ABSTRACT

BACKGROUND: Histological disease severity assessment in ulcerative colitis (UC) has become a mainstay in clinical endpoints definition (“histologic remission”) in clinical trials of UC. Several scores are established in the microscopical assessment of disease activity, but the Nancy index (NI) stands out being a histological index with the least amount of scoring items among these scores. To which extent histologic assessment using NI is affected by interobserver reliability in a real word setting, is poorly understood. We therefore performed a single-center retrospective analysis of NI assessment in patients with UC.

METHODS: We retrospectively evaluated the NI in two independent cohorts (total: 1085 biopsies, 547 UC patients) of clinically diagnosed UC patients, who underwent colonoscopy between 2007 and 2020. Cohort #1 consisted of 637 biopsies from 312 patients, Cohort #2 consisted of 448 biopsies from 235 patients. Two blinded pathologists with different levels of expertise scored all biopsies of each cohort. A consensus conference was held for cases with discrepant scoring results. Finally, an overall consensus scoring was obtained from both cohorts.

RESULTS: The interobserver-agreement of the NI was substantial after the assessment of 1085 biopsy samples (κ = 0.796 [95%-CI: 0.771-0.820]). An improvement of the interobserver-agreement was found with growing numbers of samples evaluated by both observers (Cohort #1: κ = 0.772 [95%-CI: 0.739-0.805]; Cohort #2: κ = 0.829 [95%-CI: 0.793-0.864]). The interobserver discordance was the highest in NI grade 1 (observer 1: n=128; observer 2: n=236). Interobserver discordance was the lowest in NI grades 0 (observer 1: n=504; observer 2: n=479) and 3 (observer 1: n=71; observer 2: n=66).

CONCLUSION: The NI is an easy-to-use index with high interobserver reliability to assess the histological disease activity of UC patients in a real-world setting. While NI grades 0 and 3 had a high level of agreement between the observers, NI grade 1 had a poorer agreement-level. This highlights the clinical need to specify histological characteristics leading to NI grade 1.

PMID:36282973 | DOI:10.1093/ecco-jcc/jjac146