Tag: statistics

Surg Endosc. 2022 Jun 29. doi: 10.1007/s00464-022-09387-4. Online ahead of print.

ABSTRACT

INTRODUCTION: Roux-en-Y gastric bypass (RYGB) significantly alters the gut microbiome and may be a mechanism for post-operative cardiovascular disease improvement. We have previously found an association between the class of peri-operative, intravenous antibiotic administered at the time of RYGB and the resolution rate of hypertension suggesting the gut microbiome as a mechanism. In this study, we performed a prospective study of RYGB to determine if a single intravenous antibiotic could alter the gastrointestinal microbial composition.

METHODS: Patients undergoing RYGB were randomized to a single, peri-operative antibiotic of intravenous cefazolin (n = 8) or clindamycin (n = 8). Stool samples were collected from four-time points: 2 weeks pre-op (- 2w), 2 days pre-op (- 2d), 2 weeks post-op (+ 2w) and 3 months post-op (+ 3m). Stool samples were processed for genomic DNA followed by Illumina 16S rRNA gene sequencing and shotgun metagenomic sequencing (MGS).

RESULTS: A total of 60 stool samples (- 2w, n = 16; – 2d, n = 15; + 2w, n = 16; + 3m, n = 13) from 16 patients were analyzed. 87.5% of patients were female with an average age of 48.6 ± 12.2 years and pre-operative BMI of 50.9 ± 23.3 kg/m². RYGB induced statistically significant differences in alpha and beta diversity. There were statistically significant differences in alpha diversity at + 2w and beta diversity at + 3m due to antibiotic treatment. MGS revealed significantly distinct gut microbiota with 11 discriminatory metagenomic assembled genomes driven by antibiotic treatment at 3 months post-op, including increased Bifidobacterium spp. with clindamycin.

CONCLUSION: RYGB induces significant changes in the gut microbiome at 2 weeks that are maintained 3 months after surgery. However, the single peri-operative dose of antibiotic administered at the time of RYGB induces unique and persisting changes to the gut microbiome that are antibiotic-specific. Increased Bifidobacterium spp. with clindamycin administration may improve the metabolic efficacy of RYGB when considering gut-microbiome driven mechanisms for blood pressure resolution.

PMID:35768736 | DOI:10.1007/s00464-022-09387-4

Behav Res Methods. 2022 Jun 29. doi: 10.3758/s13428-022-01895-4. Online ahead of print.

ABSTRACT

The characteristics of big data, including high volume, increased variety, and velocity, pose special challenges for data analysis. As these characteristics generally preclude manual data inspection and processing, researchers must often use computational methodologies to deal with this type of data; techniques that may be unfamiliar to nonspecialists, including behavioral scientists. However, previous data analytics methodologies within the field of computer science, developed to handle the generic tasks of data collection, preprocessing, and analysis, can be appropriated for use in other disciplines. These methodologies involve a sequential pipeline of quality checks to prepare data sets for analysis and application. Building upon these methodologies, this paper describes the Big Data Quality & Statistical Assurance (BDQSA) model, applicable for researchers in the behavioral sciences. It involves a series of data preprocessing tasks, to achieve data understanding, as well as data screening, cleaning, and transformation. These are followed by a statistical quality phase, which includes extraction of the relevant data subset, type conversions, ensuring sample representativeness when appropriate, and assessing statistical assumptions. The resulting model thereby provides methodological guidance for the preprocessing of behavioral science big data, aimed at ensuring acceptable data quality before analysis is undertaken. Sample R code snippets demonstrating the application of this model are provided throughout the paper.

PMID:35768746 | DOI:10.3758/s13428-022-01895-4

Eye (Lond). 2022 Jun 29. doi: 10.1038/s41433-022-02139-7. Online ahead of print.

ABSTRACT

BACKGROUND: To investigate the morphological retinal parameters associated with retinal sensitivity status in retinitis pigmentosa (RP) through a quantitative multimodal imaging approach.

METHODS: The study was designed as an observational, prospective case series, including RP patients and healthy controls. Multimodal imaging included fundus autofluorescence (FAF), structural optical coherence tomography (OCT), OCT angiography (OCTA) and microperimetry (MP). The follow-up lasted 12 months. For each imaging modality, we performed an overall quantitative analysis and a detailed investigation based on the ETDRS-9 sectors grid. Quantitative parameters included the thickness of each retinal and choroidal layer, vessel density (VD), choriocapillaris porosity (CCP), FAF intensity and MP retinal sensitivity.

RESULTS: We included 40 eyes (40 patients) affected by RP and 40 healthy eyes (40 controls). Mean baseline BCVA was 0.14 ± 0.18 LogMAR, with 0.18 ± 0.24 LogMAR after 1-year of follow-up. RP eyes showed statistically significant alterations of retinal and choroidal layers on the ETDRS-9 sectors grid, significant reduction of VD values and MP retinal sensitivity, and significantly higher CCP than controls. The inner retinal layers proved closely associated with the functional integrity of the posterior pole. In addition, our ROC analysis provided quantitative cutoffs connected significantly with a high probability of observing a partial sparing of MP retinal sensitivity.

CONCLUSIONS: The inner retinal layers are closely associated with the functional integrity of the posterior pole in RP. FAF intensity reduction may be interpreted as lipofuscin metabolism impairment inducing increased phototoxic distress for retinal structures. Vascular involvement contributes to the morpho-functional deterioration of the macular region in RP.

PMID:35768721 | DOI:10.1038/s41433-022-02139-7

Learn Behav. 2022 Jun 29. doi: 10.3758/s13420-022-00537-1. Online ahead of print.

ABSTRACT

It is well established that decay and interference are the two main causes of forgetting. In the present study, we specifically focus on the impact of interference on memory forgetting. To do so, we tested Guinea baboons (Papio papio) on a visuo-motor adaptation of the Serial Reaction Time task in which a target sequence is repeated, and a random sequence is interposed between repetitions, a similar situation as the one used in the Hebb repetition paradigm. In this task, one three-item sequence, the repeated sequence, was presented every second trial and interleaved with random sequences. Interference was implemented by using random sequences containing one item that was also part of the repeated sequence. In a first condition, the overlapping item was located at the same position as the repeated sequence. In a second condition, the overlapping item was located at one of the two other positions. In a third condition, there was no overlap between repeated and random sequences. Contrary to previous findings, our results reveal similar learning slopes across all three conditions, suggesting that interference did not affect sequence learning in the conditions tested. Findings are discussed in the light of previous research on sequence learning and current models of memory and statistical learning.

PMID:35768719 | DOI:10.3758/s13420-022-00537-1

J Assoc Res Otolaryngol. 2022 Jun 29. doi: 10.1007/s10162-022-00853-3. Online ahead of print.

ABSTRACT

Velocity storage is a centrally-mediated mechanism that processes peripheral vestibular inputs. One prominent aspect of velocity storage is its effect on dynamic responses to yaw rotation. Specifically, when normal human subjects are accelerated to constant angular yaw velocity, horizontal eye movements and perceived angular velocity decay exponentially with a time constant circa 15-30 s, even though the input from the vestibular periphery decays much faster (~ 6 s). Peripheral vestibular damage causes a time constant reduction, which is useful for clinical diagnoses, but a mechanistic explanation for the relationship between vestibular damage and changes in these behavioral dynamics is lacking. It has been hypothesized that Bayesian optimization determines ideal velocity storage dynamics based on statistics of vestibular noise and experienced motion. Specifically, while a longer time constant would make the central estimate of angular head velocity closer to actual head motion, it may also result in the accumulation of neural noise which simultaneously degrades precision. Thus, the brain may balance these two effects by determining the time constant that optimizes behavior. We applied a Bayesian optimal Kalman filter to determine the ideal velocity storage time constant for unilateral damage. Predicted time constants were substantially lower than normal and similar to patients. Building on our past work showing that Bayesian optimization explains age-related changes in velocity storage, we also modeled interactions between age-related hair cell loss and peripheral damage. These results provide a plausible mechanistic explanation for changes in velocity storage after peripheral damage. Results also suggested that even after peripheral damage, noise originating in the periphery or early central processing may remain relevant in neurocomputations. Overall, our findings support the hypothesis that the brain optimizes velocity storage based on the vestibular signal-to-noise ratio.

PMID:35768706 | DOI:10.1007/s10162-022-00853-3

Eur Arch Otorhinolaryngol. 2022 Jun 29. doi: 10.1007/s00405-022-07526-0. Online ahead of print.

ABSTRACT

PURPOSE: Our aim was to analyze the patients with diabetic rhino-orbital-cerebral mucormycosis that we have treated in our clinic in the last 5 years, and to reveal the altering conditions with COVID-19.

MATERIALS AND METHODS: A retrospective study was conducted on 39 rhino-orbital-cerebral mucormycosis (ROCM) patients with diabetes mellitus between 2017 and 2022. The patients were divided into two groups as those associated with and not associated with COVID-19 and compared.

RESULTS: Thirty-nine diabetic patients were included in the study, with 15 (38.5%) of them being COVID-19 associated mucormycosis (CAM) group. CAM patients showed higher orbital involvement and cavernous sinus involvement (p = 0.002 and p = 0.013, respectively). The mortality rate in the non-COVID-19 associated mucormycosis (non-CAM) group was statistically higher in patients with intracranial and cavernous sinus involvement (p = 0.015 and p = 0.033, respectively). The difference between the overall survival of the CAM patients and non-CAM patients was not statistically significant (p = 0.741).

CONCLUSIONS: With COVID-19, progressive mucormycosis accompanied by orbital and intracranial involvement is observed more frequently. However, on the contrary, the mortality rate in COVID-19-associated mucormycosis is considerably lower than expected. The fact that temporary immune suppression can be ameliorated with adequate supportive treatment and liposomal amphotericin-B which can be given to patients in high doses may explain this situation. It has been attained hints that the essential factor in the treatment of COVID-19-associated ROCM is the control of the underlying disease and to be cautious in the decision of early aggressive surgery.

PMID:35768700 | DOI:10.1007/s00405-022-07526-0

Lung. 2022 Jun 30. doi: 10.1007/s00408-022-00549-8. Online ahead of print.

ABSTRACT

PURPOSE: The recommended treatment for small-cell lung cancer (SCLC) currently is surgery in stage I disease. We wondered about stage II SCLC and present a meta-analysis on mean-survival of patients that underwent surgery for stage I and II compared to controls.

METHODS: A systematic literature search was performed on December 01st 2021 in Medline, Embase and Cochrane Library. We considered studies published on the effect of surgery in SCLC since 2004 and assessed them using ROBINS-I. We preformed I²-tests, Q-statistics, DerSimonian-Laird tests and Egger-regression. The meta-analysis was conducted according to PRISMA.

RESULTS: Out of 6826 records, seven studies with a total of 11,241 patients (‘surgery group’: 3911 patients; ‘non-surgery group’: 7330; treatment period: 1984-2015) were included. Heterogeneity between the studies was revealed in absence of any publication bias. Patient characteristics did not differ between the groups (p-value > 0.05). The mean-survival in an analysis of patients in stage I was 36.7 ± 10.8 months for the ‘surgery group’ and 20.3 ± 5.7 months for the ‘non-surgery group’ (p-value = 0.0084). A combined analysis of patients in stage I and II revealed a mean-survival of 32.0 ± 16.7 months for the ‘surgery group’ and 19.1 ± 6.1 months for the ‘non-surgery group’ (p-value = 0.0391). In a separate analysis of stage II, we were able to demonstrate a significant survival benefit after surgery (21.4 ± 3.6 versus 16.2 ± 3.9 months; p-value = 0.0493).

CONCLUSION: Our meta-analysis shows a significant survival benefit after surgery not only in the recommended stage I but also in stage II SCLC. Our data suggests that both stages should be considered for surgery of early SCLC.

PMID:35768664 | DOI:10.1007/s00408-022-00549-8

Knee Surg Sports Traumatol Arthrosc. 2022 Jun 29. doi: 10.1007/s00167-022-07033-z. Online ahead of print.

ABSTRACT

PURPOSE: To explore in vivo kinematical behavior of the same total knee arthroplasty (TKA) cruciate-retaining (CR) femoral design with either medial-congruent (MC) or ultra-congruent (UC) inlay using model-based dynamic radiostereometric analysis (RSA). The hypothesis was that there would be comparable kinematics between the two groups.

METHODS: A cohort of 16 randomly selected patients (8 MC Persona Zimmer, 8 UC Persona Zimmer) was evaluated through dynamic radiostereometric analysis (RSA) at a minimum of 9 months after TKA, during the execution of a sit-to-stand. The antero-posterior (AP) translation of the femoral component and the AP translation of the low point of medial and lateral femoral compartments were compared through Student’s t test (p < 0.05).

RESULTS: Both groups showed a medial pivot behavior, with a significantly greater anterior translation of the Low Point of the lateral compartment with respect to the medial compartment (MC medial range: 2.4 ± 2.4 mm; MC lateral range: 7.7 ± 3.0 mm; p < 0.001 – UC medial range: 3.3 ± 3.3 mm; UC lateral range: 8.0 ± 3.2 mm; p < 0.001). A statistically significant greater degree of flexion was clinically recorded at follow-up visit in the MC group respect to the UC group (126° vs 101°-p = 0.003).

CONCLUSION: The present study did not show difference in the medial pivot behavior between ultra-congruent and medial-congruent total knee arthroplasty when implanted with mechanical alignment; however, the MC group demonstrated a greater degree of flexion. The MC design examined is a valid alternative to the UC design, allowing to achieve a screw-home movement restoration combined with a high flexion.

LEVEL OF EVIDENCE: IV.

PMID:35768651 | DOI:10.1007/s00167-022-07033-z

J Prev (2022). 2022 Jun 29. doi: 10.1007/s10935-022-00688-x. Online ahead of print.

ABSTRACT

This is an analysis of conditions favouring the cumulative COVID-19 infection rates between February 2020 and April 2021 in Romania, as an Eastern European society, at the local community level. What are the socio-demographic and location profiles of the local communities by considering their infection rates with SARS-COV-2 at the beginning of the pandemia as a dependent variable? This is the research question that structured the approach. The general hypothesis that is tested is that reported infections with the new coronavirus are higher in communities of higher social interactions. The theoretical model is tested by multiple regression analysis working on more than 2500 local communities, out of the 3200 local administrative units of the country. Data basis for testing the model are coming from the National Institute of Public Health and the National Institute of Statistics. Higher COVID infection rates are favoured by socio-human capital, the regional capital, migration abroad experience, and modernity at a local level. Other factors are captured by the cultural areas as subregions of historical regions of the country, formed by neighboured similar counties. Nuclei of higher infections with COVID-19 are located in developed communities around large cities, high modernity areas, and communities of high emigration abroad. Principles for health public policies are formulated at the end by considering the role of decentralisation, and better ways to do a rapid and good diagnosis at local levels. To our knowledge, this is one of the very few studies that address determinants of COVID-19 infections at the local community level for a whole country in Europe. New research questions are formulated as an outcome of conclusions. They could be answered only by supplementary multilevel research. Limitations of analysis are derived from the fact that we are using only ecological, spatially aggregated data, and not multilevel ones. Relations that were recorded to the community could not be transferred to the individual level.

PMID:35768636 | DOI:10.1007/s10935-022-00688-x

J Neurooncol. 2022 Jun 29. doi: 10.1007/s11060-022-04057-w. Online ahead of print.

ABSTRACT

INTRODUCTION: Gliosarcomas are extremely rare malignant brain tumors, which can be classified as primary gliosarcoma (PGS) if the tumors arise de novo or secondary gliosarcoma (SGS) in patients who had previously been treated for glioblastoma. Given their rarity, it is unclear if PGS is clinically and genetically different from SGS. This meta-analysis aimed to investigate the clinicopathological features, prognostic survivals, and molecular profiles of these rare tumors.

METHODS: We searched PubMed and Web of Science for relevant studies. Odds ratio (OR), hazard ratio (HR), and their 95% confidence intervals (CI) were pooled using the random-effect model.

RESULTS: We included eight studies with 239 PGS and 79 SGS for meta-analyses. Compared to PGS, SGS occurred at a younger age and had lower rates of gross total resection and radiation therapy. Bevacizumab was more commonly administered in SGS. SGS patients had a significantly worse PFS (HR 0.60; 95% CI 0.40-0.89) and OS (HR 0.46; 95% CI 0.31-0.68) in comparison to PGS. The incidences of EGFR mutation, IDH mutation, and MGMT methylation were not statistically different between PGS and SGS.

CONCLUSION: Our results demonstrated that PGS and SGS had distinct clinicopathological profiles and prognoses but shared similar genetic profiles. This study facilitates our understanding of how these two malignant brain tumors behave clinically, but future studies will be required to elucidate the genetic pathways of PGS and SGS.

PMID:35768633 | DOI:10.1007/s11060-022-04057-w