Category: Statistics

Sci Rep. 2021 Apr 8;11(1):7806. doi: 10.1038/s41598-021-86937-1.

ABSTRACT

In this study, statistical analysis and spatial distribution were performed to compare raw data and centred log-ratio (clr) transformed data of three copper (Cu), lead (Pb), and zinc (Zn) potentially toxic elements (PTEs) concentration for 550 surface soil samples in Khuzestan plain. The results of both approaches showed that classical univariate analysis and compositional data analysis are essential to find the real structure of data and clarify its different aspects. Results also indicated that spatial distributions of raw data and clr-transformed data were completely different in three studied metals. Raw data necessarily shows the effects of anthropogenic activities and needs an additional evaluation of human health risk assessment for these three studied elements. Data obtained from clr-coefficient maps also demonstrated the role of geological processes in the distribution pattern of potentially toxic elements (PTEs). To improve the understanding of the implications for PTE pollution and consequences for human health, a RGB colour composite map was produce to identify the potential origin of PTEs from areas with higher than typical baseline concentrations.

PMID:33833253 | DOI:10.1038/s41598-021-86937-1

Sci Rep. 2021 Apr 8;11(1):7783. doi: 10.1038/s41598-021-87087-0.

ABSTRACT

Self-assembling processes are ubiquitous phenomena that drive the organization and the hierarchical formation of complex molecular systems. The investigation of assembling dynamics, emerging from the interactions among biomolecules like amino-acids and polypeptides, is fundamental to determine how a mixture of simple objects can yield a complex structure at the nano-scale level. In this paper we present HyperBeta, a novel open-source software that exploits an innovative algorithm based on hyper-graphs to efficiently identify and graphically represent the dynamics of [Formula: see text]-sheets formation. Differently from the existing tools, HyperBeta directly manipulates data generated by means of coarse-grained molecular dynamics simulation tools (GROMACS), performed using the MARTINI force field. Coarse-grained molecular structures are visualized using HyperBeta ‘s proprietary real-time high-quality 3D engine, which provides a plethora of analysis tools and statistical information, controlled by means of an intuitive event-based graphical user interface. The high-quality renderer relies on a variety of visual cues to improve the readability and interpretability of distance and depth relationships between peptides. We show that HyperBeta is able to track the [Formula: see text]-sheets formation in coarse-grained molecular dynamics simulations, and provides a completely new and efficient mean for the investigation of the kinetics of these nano-structures. HyperBeta will therefore facilitate biotechnological and medical research where these structural elements play a crucial role, such as the development of novel high-performance biomaterials in tissue engineering, or a better comprehension of the molecular mechanisms at the basis of complex pathologies like Alzheimer’s disease.

PMID:33833280 | DOI:10.1038/s41598-021-87087-0

Sci Rep. 2021 Apr 8;11(1):7769. doi: 10.1038/s41598-021-87064-7.

ABSTRACT

Automated machine learning approaches to skin lesion diagnosis from images are approaching dermatologist-level performance. However, current machine learning approaches that suggest management decisions rely on predicting the underlying skin condition to infer a management decision without considering the variability of management decisions that may exist within a single condition. We present the first work to explore image-based prediction of clinical management decisions directly without explicitly predicting the diagnosis. In particular, we use clinical and dermoscopic images of skin lesions along with patient metadata from the Interactive Atlas of Dermoscopy dataset (1011 cases; 20 disease labels; 3 management decisions) and demonstrate that predicting management labels directly is more accurate than predicting the diagnosis and then inferring the management decision ([Formula: see text] and [Formula: see text] improvement in overall accuracy and AUROC respectively), statistically significant at [Formula: see text]. Directly predicting management decisions also considerably reduces the over-excision rate as compared to management decisions inferred from diagnosis predictions (24.56% fewer cases wrongly predicted to be excised). Furthermore, we show that training a model to also simultaneously predict the seven-point criteria and the diagnosis of skin lesions yields an even higher accuracy (improvements of [Formula: see text] and [Formula: see text] in overall accuracy and AUROC respectively) of management predictions. Finally, we demonstrate our model’s generalizability by evaluating on the publicly available MClass-D dataset and show that our model agrees with the clinical management recommendations of 157 dermatologists as much as they agree amongst each other.

PMID:33833293 | DOI:10.1038/s41598-021-87064-7

Ann Plast Surg. 2021 Mar 18. doi: 10.1097/SAP.0000000000002859. Online ahead of print.

ABSTRACT

BACKGROUND: On March 11, 2020, the World Health Organization declared COVID-19 as a global pandemic. As a response, the United States shut down public gatherings and businesses in an effort to quarantine. This included the stopping of elective operations, which greatly affected plastic surgeons and their practices during the initial shutdown.

OBJECTIVES: We aim to study the early impact of COVID-19 on the financial implications and practice patterns of plastic surgeons in the state of California during the initial shutdown of elective surgery and provide guidelines for effective management during future crises.

METHODS: A 20-question survey was sent using Qualtrics XM software to 851 surgeon members of the California Society of Plastic Surgeons. The survey was open from May 13, 2020, to May 29, 2020. Standard statistical analysis was completed to compare private practice and nonprivate practice plastic surgeons.

RESULTS: We had a total of 140 respondents to our survey for a 16.5% response rate. The majority (77.1%) of the respondents were in a private practice setting. Private practice plastic surgeons reported a higher financial impact with a 79% reduction in financial income compared with nonprivate practice plastic surgeons at a 37% reduction (P < 0.0001). Additionally, private practice plastic surgeons demonstrated a higher reduction in case volume and were more likely to lay off or furlough staff, close their practice, and apply for loans (P < 0.001).

CONCLUSIONS: Our survey study showed that private practice plastic surgeons in the state of California faced the most financial hardship during the early shutdown of the COVID-19 pandemic. It serves as a valuable snapshot in our economic history and depicts the heavy financial impact of the stopping of elective surgery. Since the reopening of practices, new guidelines have been implemented to maintain safe elective surgery while the pandemic continues. Further follow-up studies on both the state and national level need to be completed to see the continued financial effects on private and nonprivate plastic surgery practices since the reopening and resumption of elective surgery.

PMID:33833188 | DOI:10.1097/SAP.0000000000002859

Transl Psychiatry. 2021 Apr 8;11(1):210. doi: 10.1038/s41398-021-01325-7.

ABSTRACT

Observational studies have suggested bidirectional associations between psychiatric disorders and COVID-19 phenotypes, but results of such studies are inconsistent. Mendelian Randomization (MR) may overcome the limitations of observational studies, e.g., unmeasured confounding and uncertainties about cause and effect. We aimed to elucidate associations between neuropsychiatric disorders and COVID-19 susceptibility and severity. To that end, we applied a two-sample, bidirectional, univariable, and multivariable MR design to genetic data from genome-wide association studies (GWASs) of neuropsychiatric disorders and COVID-19 phenotypes (released in January 2021). In single-variable Generalized Summary MR analysis, the most significant and only Bonferroni-corrected significant result was found for genetic liability to BIP-SCZ (a combined GWAS of bipolar disorder and schizophrenia as cases vs. controls) increasing risk of COVID-19 (OR = 1.17, 95% CI, 1.06-1.28). However, we found a significant, positive genetic correlation between BIP-SCZ and COVID-19 of 0.295 and could not confirm causal or horizontally pleiotropic effects using another method. No genetic liabilities to COVID-19 phenotypes increased the risk of (neuro)psychiatric disorders. In multivariable MR using both neuropsychiatric and a range of other phenotypes, only genetic instruments of BMI remained causally associated with COVID-19. All sensitivity analyses confirmed the results. In conclusion, while genetic liability to bipolar disorder and schizophrenia combined slightly increased COVID-19 susceptibility in one univariable analysis, other MR and multivariable analyses could only confirm genetic underpinnings of BMI to be causally implicated in COVID-19 susceptibility. Thus, using MR we found no consistent proof of genetic liabilities to (neuro)psychiatric disorders contributing to COVID-19 liability or vice versa, which is in line with at least two observational studies. Previously reported positive associations between psychiatric disorders and COVID-19 by others may have resulted from statistical models incompletely capturing BMI as a continuous covariate.

PMID:33833219 | DOI:10.1038/s41398-021-01325-7

Ann Plast Surg. 2021 Mar 18. doi: 10.1097/SAP.0000000000002800. Online ahead of print.

ABSTRACT

INTRODUCTION: Intraoperative laser angiography via indocyanine green (ICG) has become a valuable tool in objectively assessing tissue perfusion in reconstructive procedures. Studies have demonstrated the utility of ICG angiography (ICGA) for decreasing both mastectomy skin flap necrosis and wound healing complications in abdominal wall reconstruction. This tool has not been studied in lower extremity oncologic reconstruction. The objective of this study was to compare postoperative complications in lower extremity oncologic reconstruction managed with or without laser-assisted ICGA.

METHODS: A retrospective chart review was performed of patients undergoing complex lower extremity oncologic reconstruction at a single institution between 2000 and 2018. Patient information regarding demographics, comorbidities, operative procedures, and postoperative complications was analyzed.

RESULTS: Sixty-one patients were identified in our study. As some patients underwent multiple reconstructive surgeries, a total of 76 reconstructive procedures were analyzed. Patients with plastic surgery reconstruction using ICGA (n = 36) were compared with those without, non-ICGA (n = 40). No significant differences in age, sex, smoking status, chemotherapy, or radiation history were identified between cohorts. The total number of postoperative complications did not statistically differ between cohorts. There was no statistically significant difference in the number of required reoperation because of a postoperative complication between the ICGA and non-ICGA groups (0.44 vs 0.4).

CONCLUSIONS: The incidence of postoperative wound complications after complex lower extremity oncologic reconstruction remains high. The findings of our study suggest that clinical judgment of flap and soft tissue viability, as compared with ICGA, may lead to comparable operative outcomes and be more cost-effective. Long-term follow-up and prospective studies are needed to further investigate this trend.

PMID:33833180 | DOI:10.1097/SAP.0000000000002800

Ann Plast Surg. 2021 Mar 18. doi: 10.1097/SAP.0000000000002809. Online ahead of print.

ABSTRACT

OBJECTIVE: A large factor influencing a patient’s choice of aesthetic plastic surgeons is online patient reviews.

METHODS/TECHNIQUE: Plastic surgeons whose practices are located in counties within the New York metro area were included. Selected surgeons were divided into private and academic surgeons (defined as having a residency program). For each surgeon, the quantity and quality of their Google reviews were collected.

RESULTS/COMPLICATIONS: A total of 145 aesthetic surgeons from the New York area were included in the study, both private (n = 126) and academic (n = 19). Given the small size of the latter cohort, 19 private aesthetic surgeons were randomly selected, and compared with the academic surgeons, it was shown that private surgeons had both higher average quality and quantity of online patient Google reviews (confidence interval, 95%; P = 0.0223). Similar results were found when comparing all private American Society for Aesthetic Plastic Surgery (ASAPS) surgeons (n = 126) with all academic ASAPS surgeons (n = 19); private ASAPS surgeons had a higher average rating and number of reviews when compared with academic surgeons, again representing a statistically significant difference for the quality of online reviews between private and academic surgeons (confidence interval, 95%; P = 0.031975).

CONCLUSIONS: There is a statistically significant difference in both the quality and quantity of online ratings for private and academic aesthetic surgeons.

PMID:33833182 | DOI:10.1097/SAP.0000000000002809

Ann Plast Surg. 2021 Mar 24. doi: 10.1097/SAP.0000000000002760. Online ahead of print.

ABSTRACT

INTRODUCTION: Breast reconstruction in the prepectoral plane has recently fallen into favor. Minimizing the number of revisionary procedures after reconstruction is an important factor in improving patient care, but long-term studies on the effects of prepectoral reconstruction are limited. In this study, we compare the revision rates after delayed-immediate, autologous reconstruction between prepectoral and subpectoral reconstructions.

METHODS: Postoperative charts for all patients undergoing subpectoral or prepectoral delayed-immediate autologous breast reconstruction were retrospectively reviewed at our single tertiary-care institution between 2009 and 2018. Patient demographics, comorbidities, and oncologic history were recorded. Charts after second stage reconstruction were reviewed for up to eighteen months to determine if revisions were necessary. Data collected included the total number of surgeries performed, the average number of procedures performed during each surgery, and the type of revision that was performed. Statistical tests included the chi squared test, unpaired t-test, and logistic regressions.

RESULTS: Data from 89 patients with 125 breast reconstructions were collected. There was a 41.6% of these that were prepectoral reconstructions (P), and 58.4% were subpectoral reconstructions (S). For both groups, nipple sparing, followed by skin sparing mastectomies were most common. Mastectomy rates were not statistically different. Fewer breasts in the prepectoral cohort required any revisions (P, 21.2% vs S, 47.9%; P = 0.002). The subpectoral cohort had higher rates of soft tissue rearrangement (P, 7.7% vs S, 21.9%, P = 0.032), fat grafting (P, 9.6% vs S, 27.4%; P = 0.014), and nipple reconstruction (P: 5.8% vs 20.5%, P = 0.020). Mean follow-up time was not significantly different between patient groups (P, 290.5 days vs S, 375.0 days, P = 0.142). Subpectoral expander placement was found to be the only variable independently predictive of requiring 1 or more revision (P = 0.034).

CONCLUSIONS: Breast reconstruction performed in the prepectoral plane is associated with lower overall rates of revisionary surgery. Rates of soft tissue rearrangement, fat grafting, and nipple reconstruction after autologous reconstruction trended higher in subpectoral reconstructions.

PMID:33833169 | DOI:10.1097/SAP.0000000000002760

Ann Plast Surg. 2021 Apr 5. doi: 10.1097/SAP.0000000000002702. Online ahead of print.

ABSTRACT

BACKGROUND: Pierre Robin sequence (PRS) is a triad of congenital facial abnormalities that can present as a syndrome (syndromic PRS [sPRS]) or an isolated entity (isolated PRS [iPRS]). Patients with PRS can develop airway and feeding problems that may result in failure to thrive. Mandibular distraction osteogenesis (MDO) is a method for improving the functional issues associated with breathing and feeding. There is a Paucity of literature evaluating the outcomes of MDO between sPRS and iPRS patients.

METHODS: An institutional review board-approved retrospective review of PRS patients managed by a single surgeon and treated with MDO between January 2015 and December 2019 at a tertiary referral hospital was performed. The patients were stratified into iPRS or sPRS based on gene testing. Airway outcome measures included avoidance of tracheostomy, relief of sleep apnea, and oxygen saturation improvement. Primary feeding measures included achievement of full oral feeds and growth/weight gain. Statistical analysis included t tests and χ2 tests where appropriate using SPSS.

RESULTS: Over the study period, of the 29 infants with PRS, 55% identified as iPRS and 45% as sPRS. There were no significant differences in the patient characteristics, apnea-hypoxia index (22.27 ± 12.27) and laryngeal view (3 ± 0.79) pre-MDO. After MDO, 83% of the subjects achieved a positive feeding outcome and 86% achieved a positive airway outcome with no statistical significance between sPRS and iPRS (P = 0.4369). There was a statistically significant change post-MDO in apnea-hypoxia index (5.24 ± 4.50, P = 0.02) and laryngeal view (1.59 ± 1.00, P = 0.01).

CONCLUSIONS: Our recent experience would lead us to believe that sPRS patients have greater morbidities and challenging clinical developments that, when properly evaluated, can be managed by MDO. There is a potential role for MDO in reducing the need for traditional surgical interventions for respiratory and feeding problems in both iPRS and sPRS patients.

PMID:33833161 | DOI:10.1097/SAP.0000000000002702

Ann Plast Surg. 2021 Mar 31. doi: 10.1097/SAP.0000000000002826. Online ahead of print.

ABSTRACT

PURPOSE: In an attempt to reduce the incidence of infectious complications after tissue expander-based breast reconstruction, the routine administration of postoperative antibiotics regimen is common in many practices. In recent years, there has been a plethora of reports scrutinizing the prophylactic use of postoperative antibiotics in this setting. The aim of this study was to determine the efficacy of prolonged administration of postoperative antibiotics compared with perioperative-only antibiotic administration for prophylaxis after tissue expander placement for immediate mastectomy reconstruction.

METHODS AND MATERIALS: A retrospective chart review of all patients who underwent immediate tissue expander placement after mastectomy at our institution from June 2005 to September 2018 was performed. All patients in the study received perioperative intravenous antibiotics 30 to 60 min preoperatively and for 24 hours postoperatively. Patients were divided into 2 groups. Patients in group A did not receive antibiotics beyond the perioperative period. Patients in group B received oral antibiotics for at least 7 days postoperatively in addition to the perioperative intravenous antibiotics. The 2 groups were compared for demographics and prevalence of risk factors such as radiation, chemotherapy, smoking, and diabetes. The incidence of complications such as infection, wound complications, hematoma, seroma, capsular contracture, loss of tissue expander, and reoperations was assessed.

SUMMARY OF RESULTS: A total of 529 patients were included in the study, of which 241 were in group A and 288 were in group B. The total number of breasts reconstructed in group A was 398, whereas in group B, it was 466 breasts. Patients were followed up to 5 months postoperatively in each group. There were no statistically significant differences in the demographic and patient characteristics among the 2 groups. The incidence of infection in group A was 23.24% and in group B was 21.53% (P = 0.412). The incidence of other complications follows the same trend when comparing group A versus B.

CONCLUSIONS: This retrospective study shows that the routine use of postoperative antibiotics after tissue expander placement for immediate mastectomy reconstruction does not result in reduction in the incidence of common complications or improvement of clinical outcomes.

PMID:33833164 | DOI:10.1097/SAP.0000000000002826