Tag: statistics

Mol Imaging Biol. 2023 Jan 25. doi: 10.1007/s11307-023-01803-y. Online ahead of print.

ABSTRACT

OBJECTIVES: To evaluate the performance of machine learning-augmented MRI-based radiomics models for predicting response to neoadjuvant chemotherapy (NAC) in soft tissue sarcomas.

METHODS: Forty-four subjects were identified retrospectively from patients who received NAC at our institution for pathologically proven soft tissue sarcomas. Only subjects who had both a baseline MRI prior to initiating chemotherapy and a post-treatment scan at least 2 months after initiating chemotherapy and prior to surgical resection were included. 3D ROIs were used to delineate whole-tumor volumes on pre- and post-treatment scans, from which 1708 radiomics features were extracted. Delta-radiomics features were calculated by subtraction of baseline from post-treatment values and used to distinguish treatment response through univariate analyses as well as machine learning-augmented radiomics analyses.

RESULTS: Though only 4.74% of variables overall reached significance at p ≤ 0.05 in univariate analyses, Laws Texture Energy (LTE)-derived metrics represented 46.04% of all such features reaching statistical significance. ROC analyses similarly failed to predict NAC response, with AUCs of 0.40 (95% CI 0.22-0.58) and 0.44 (95% CI 0.26-0.62) for RF and AdaBoost, respectively.

CONCLUSION: Overall, while our result was not able to separate NAC responders from non-responders, our analyses did identify a subset of LTE-derived metrics that show promise for further investigations. Future studies will likely benefit from larger sample size constructions so as to avoid the need for data filtering and feature selection techniques, which have the potential to significantly bias the machine learning procedures.

PMID:36695966 | DOI:10.1007/s11307-023-01803-y

Oral Maxillofac Surg. 2023 Jan 25. doi: 10.1007/s10006-023-01138-6. Online ahead of print.

ABSTRACT

OBJECTIVES: Aim of this study was to assess the influence of restorative treatment timing on the periodontal, patient and operator-reported outcomes following crown lengthening surgery (CLS).

MATERIALS AND METHODS: Eighteen study participants requiring CLS were divided into two groups based on prosthetic rehabilitation timing (6 or 14 weeks postoperatively). Clinical parameters were recorded around treated and neighboring teeth before and after surgery, 6 and 14 weeks postoperatively, at prosthesis delivery, and three and six months after. Soft tissue and radiographic bone changes were evaluated. Patients assessed their perception of the procedure by means of a questionnaire. The final treatment outcome was rated by both patients and prosthodontists.

RESULTS: CLS resulted in statistically significant and stable apical displacement of the gingival margin, at both treated and adjacent sites. Plaque and bleeding scores remained low throughout. No statistically significant differences were observed between groups for any clinical or radiographic parameter examined. Healing was uneventful and treatment outcome was satisfying for both patients and prosthodontists, without statistically significant differences between groups.

CONCLUSIONS: The present study has been characterized as pilot, because it was not possible to reach the sample size indicated by the a priori power analysis. CLS is an effective pre-prosthetic procedure as long as it is performed under a certain surgical protocol which predicts for at least a 3 mm distance between bone crest and the flap margin at suturing. Within the limitations of this study, six weeks after surgery may be an adequate healing time for the onset of prosthetic restoration.

CLINICAL RELEVANCE: Crown lengthening surgery is commonly performed in daily clinical practice with the aim to restore teeth with short clinical crowns. Based on periodontal, patient and operator-reported criteria, 6 weeks after CLS may be adequate healing time before the onset of prosthetic restoration.

TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03947658, 13/05/2019, retrospectively registered.

PMID:36695965 | DOI:10.1007/s10006-023-01138-6

J Math Biol. 2023 Jan 25;86(3):37. doi: 10.1007/s00285-023-01869-w.

ABSTRACT

In this paper, we propose a general viral infection model to incorporate two infection modes (virus-to-cell mode and cell-to-cell mode), the CTL immune response, and the distributed intracellular delays during the processes of viral infection, viral production, and CTLs recruitment. We investigate the existence, the uniqueness, and the global stability of three equilibria: infection-free equilibrium [Formula: see text], immune-inactivated equilibrium [Formula: see text] and immune-activated equilibrium [Formula: see text], respectively. We prove that the viral dynamics are determined by two threshold parameters: the basic reproduction number for infection [Formula: see text] and the basic reproduction number for immune response [Formula: see text]. We also numerically explore the viral dynamics beyond stability. We use bifurcation diagrams to show that increasing the delay in CTL immune cell recruitment can induce a switch in viral load from a stable constant level to sustained oscillations, and then back to a stable equilibrium. We also compare the contributions of the two infection modes to the total infection level and identify the key parameters that would affect the percentages of virus-to-cell infection and cell-to-cell infection. Finally, we explore how Filippov control can be applied in antiretroviral therapy to reduce the viral loads.

PMID:36695964 | DOI:10.1007/s00285-023-01869-w

J Am Heart Assoc. 2023 Jan 25:e024975. doi: 10.1161/JAHA.121.024975. Online ahead of print.

ABSTRACT

Background Uncontrolled blood pressure (BP) remains a leading cause of death in the United States. The American Medical Association developed a quality improvement program to improve BP control, but it is unclear how to efficiently implement this program at scale across multiple health systems. Methods and Results We conducted BP MAP (Blood Pressure Measure Accurately, Act Rapidly, and Partner With Patients), a comparative effectiveness trial with clinic-level randomization to compare 2 scalable versions of the quality improvement program: Full Support (with support from quality improvement expert) and Self-Guided (using only online materials). Outcomes were clinic-level BP control (<140/90 mm Hg) and other BP-related process metrics calculated using electronic health record data. Difference-in-differences were used to compare changes in outcomes from baseline to 6 months, between intervention arms, and to a nonrandomized Usual Care arm composed of 18 health systems. A total of 24 safety-net clinics in 9 different health systems underwent randomization and then simultaneous implementation. BP control increased from 56.7% to 59.1% in the Full Support arm, and 62.0% to 63.1% in the Self-Guided arm, whereas BP control dropped slightly from 61.3% to 60.9% in the Usual Care arm. The between-group differences-in-differences were not statistically significant (Full Support versus Self-Guided=+1.2% [95% CI, -3.2% to 5.6%], P=0.59; Full Support versus Usual Care=+3.2% [-0.5% to 6.9%], P=0.09; Self-Guided versus Usual Care=+2.0% [-0.4% to 4.5%], P=0.10). Conclusions In this randomized trial, 2 methods of implementing a quality improvement intervention in 24 safety net clinics led to modest improvements in BP control that were not statistically significant. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT03818659.

PMID:36695297 | DOI:10.1161/JAHA.121.024975

Saudi J Gastroenterol. 2023 Jan 23. doi: 10.4103/sjg.sjg_368_22. Online ahead of print.

ABSTRACT

CONCLUSIONS: The results of this study provide an overview of the variations in microbiota diversity present in Saudi IBD patients compared to healthy controls.

RESULTS: The key finding was three negative bacterial biomarkers, Paraprevotellaceae, the Muribaculaceae families of Bacteroidetes phylum, and the Leuconostocaceae family of Firmicutes phylum, which had a higher relative abundance in healthy individuals compared to IBD patients. It was also found that primary microbiota signatures at certain genera and species levels, including Prevotella copri, Bifidobacterium adolescentis, Ruminococcus callidus, Coprococcus sp., Ruminococcus gnavus, Dorea formicigenerans, Leuconostoc, Dialister, Catenibacterium, Eubacterium biforme, and Lactobacillus mucosae, were absent in almost all IBD patients, while Veillonella dispar was absent in all healthy individuals.

METHODS: After obtaining an informed consent, fecal samples were collected from 11 participants with IBD (patients) and 10 healthy individuals (controls). The bacterial components of the microbial population were identified by next-generation sequencing of partial 16S rRNA. Statistically significant dissimilarities were observed between samples for all metrics.

BACKGROUND: Inflammatory bowel disease (IBD) is a chronic intestinal inflammatory condition attributed to a complex interaction between imbalances in the gut microbiome, environmental conditions, and a deregulated immune response. The aim of the study was to investigate the composition of the gut microbiome of Saudi patients with IBD.

PMID:36695274 | DOI:10.4103/sjg.sjg_368_22

Lung India. 2023 Jan-Feb;40(1):24-32. doi: 10.4103/lungindia.lungindia_251_22.

ABSTRACT

BACKGROUND: Asthma is defined as a chronic inflammatory disorder of the airways, characterized by bronchial hyper-responsiveness and variable airflow obstruction, that is often reversible either spontaneously or with treatment. Impulse oscillometry is a newer diagnostic modality for asthma. It is based on the measurement of sound waves reflected by airway resistance.

OBJECTIVES: The aim of this article is to study the role of impulse oscillometry in diagnosis and follow-up of bronchial asthma.

METHODS: Fifty-five clinically diagnosed bronchial asthma patients were evaluated with spirometry and impulse oscillometry before and after 3 months of inhaled treatment. The sensitivity to diagnose and follow-up was compared using proper statistical tests.

RESULTS: Impulse oscillometry was superior to spirometry in diagnosing bronchial asthma and also in accessing the treatment response after 3 months.

CONCLUSION: Impulse oscillometry is superior in predicting bronchial asthma and its parameters are also more sensitive in accessing treatment response. It can replace spirometry as it is easy to perform and effort independent.

PMID:36695255 | DOI:10.4103/lungindia.lungindia_251_22

J Minim Access Surg. 2023 Jan 9. doi: 10.4103/jmas.jmas_205_22. Online ahead of print.

ABSTRACT

CONTEXT: Competence in flexible endoscopy is essential for all surgeons during this era of minimal access surgery. However, fewer surgeons have expertise in endoscopy due to a lack of training and interest. The Indian Association of Gastrointestinal Endo Surgeons devised a short-structured training course in the art and science of endoscopy.

AIMS: This study aimed to find the impact of the endoscopy training course (Endoscopic Fellowship of Indian Association of Gastrointestinal Endo Surgeons [EFIAGES]) in improving the endoscopic skill of surgeons.

SETTINGS AND DESIGN: Twenty-two-part electronic survey forms were sent to all 375 candidates who took the course between 2016 and 2019 for this retrospective observational study.

SUBJECTS AND METHODS: The following outcome measures were noted, namely technical competence in endoscopy before the course, delegate feedback about the course modules, volume of endoscopies before and after the course and quality indicators such as reaching up to duodenum (D2) and caecum before and after the course.

STATISTICAL ANALYSIS USED: Statistical analysis of the impact of the course was done using Chi-square test.

RESULTS: Responses from 262 out of a total of 375 candidates were received. Seventy-seven per cent of trainees were pleased with content and mode of conduct of the course. The quality indicator of gastroscopy with the ability to reach D2 in 90% of the caseload was achieved by only 28% of trainees before the EFIAGES. This increased to 72% of candidates after the course and similar results were seen with colonoscopy also. Most of the candidates noted a distinct improvement in their endoscopic navigation skills subsequent to the course.

CONCLUSIONS: Endoscopy skill transfer was possible with a short-structured endoscopy course. The surgical fraternity should realise the importance of endoscopy skills in the current era of surgical practice.

PMID:36695244 | DOI:10.4103/jmas.jmas_205_22

Ann Afr Med. 2023 Jan-Mar;22(1):117-123. doi: 10.4103/aam.aam_21_22.

ABSTRACT

BACKGROUND: Many factors have been proposed to be associated with the severity of disease and mortality in COVID-19. Vitamin D had recently been reviewed as one of these factors.

AIM AND OBJECTIVES: To evaluate the association between Vitamin D and the disease severity and mortality in COVID-19.

MATERIALS AND METHODS: After approval from Institutional Ethics Committee, this prospective cohort study was carried out in selected tertiary care teaching medical institutes of Central India. Participants were COVID-19 patients of the age group of 18 years and above admitted during the study period. They were categorized into four groups as asymptomatic (Group A), mild (Group B), moderate (Group C), and severe (Group D) based on clinical symptoms, respiratory rate, oxygen saturation, and chest imaging. Serum level of Vitamin 25(OH) D was measured using chemiluminescent immunoassay. The outcome of the disease was classified as recovery and death during hospitalization. The association of sociodemographic and medical characteristics with treatment outcome was studied using an appropriate statistical test. A full logistic regression model was built for the assessment of the relationship between treatment outcomes with Vitamin D level. Further, one receiver operating characteristic curve was developed to examine the prognostic significance of Vitamin D levels in COVID-19 patients.

RESULTS: Out of 748 enrolled patients, 44 (5.88%), had severe disease (Group D). A total of 721 cases (96.39%) recovered and were discharged, whereas 27 (3.61%) died during hospitalization. Mean Vitamin D level was found to be significantly different in discharged patients compared to those who were deceased. Increasing age-adjusted odds ratio (AOR) (95% confidence interval [CI]=1.07 [1.02-1.12]), known hypertension AOR (95%CI) = 3.38 (1.13-10.08), and diabetes mellitus AOR (95%CI) =28.5 (6.04-134.13) were found to be significant predictors of death among COVID-19 patients. Increasing Vitamin D level was found to be protective against COVID-19-related death (AOR (95% CI = 0.87 [0.80-0.94]).

CONCLUSION: Vitamin D was significantly associated with the disease severity and mortality in COVID-19.

PMID:36695233 | DOI:10.4103/aam.aam_21_22

Ann Afr Med. 2023 Jan-Mar;22(1):107-111. doi: 10.4103/aam.aam_13_22.

ABSTRACT

INTRODUCTION: As per the World Health Organization, in 2005, more than 180 million people had diabetes worldwide. This figure will be more than double by 2030. Neuropathy is common and late complication of diabetes mellitus (DM). Sensory neural hearing loss which is severe at higher frequencies has been reported in Type 2 DM patients. Auditory nerve tract damage increases the latency and reduces the amplitude of the response. Evoked potential recordings evaluate the neural pathways in the central nervous system. Brainstem auditory evoked potentials (BAEP) localize anatomic structures using different waves and detect acoustic and central neuropathy (CN). Hence, brainstem evoked response of audiometry (BERA) is used widely in clinical set up.

AIMS: PRIMARY: 1. To record BERA waves in normal subjects with normal blood sugar levels (hemoglobin A₁C [HbA1C] <5.4. 2. To record BERA waves in Type 2 DM patients. (HbA1C >6.5).

SECONDARY: To study the BERA parameters with the normal subjects with blood sugar subjects and compare them with Type 2 DM patients.

MATERIALS AND METHODS: n = 30, Type 2 DM patients between the age of 35-50 years of either sex were chosen from the Diabetic Clinic of GMC, Aurangabad, Maharashtra. HbA₁C test for glycemic control and BERA waves to assess CN were recorded. n = 30 normal subjects with normal blood sugar with age and sex-matched above tests were performed.

STATISTICAL ANALYSIS: Unpaired Student’s t-test.

RESULTS: Mean ± Standard deviation of the absolute latency and interpeak latency of BERA waves at 2, 4, and 6 KHz at 80 dB in Type 2 DM patients were delayed and found to be significant as compared to control group.

CONCLUSION: The above study explains that if BAEP is recorded at higher frequencies like 6 KHz and at 80 dB, CN involvement can be detected earlier in diabetic patients. Hence, it is recommended to carry out BERA in diabetic patients at least once in a year.

PMID:36695231 | DOI:10.4103/aam.aam_13_22

Ann Afr Med. 2023 Jan-Mar;22(1):94-100. doi: 10.4103/aam.aam_178_21.

ABSTRACT

BACKGROUND: Epidemiological data on Hospital-Acquired Pneumonia (HAP) are scarce inside Intensive Care Units (ICUs).

AIM: This study aims to quantify the incidence of HAP, determine the predictors of HAP, calculate HAP-related mortality risk ratio as well as pinpoint the different risk factors contributing to mortality.

SUBJECTS AND METHODS: A prospective longitudinal study was conducted at a governmental hospital’s general ICUs over 12 months. We included adult patients admitted for at least 72 h before signs appear. We utilized a logistic regression model for fatality outcome and cox proportional hazard model for HAP outcome.

RESULTS: Of 356 patients, 133 patients developed Ventilated-Acquired Pneumonia (VAP), 76 patients with Non-Ventilated HAP (NV-HAP), as well as 147 patients did not acquire HAP. The incidence of HAP was 28 cases of HAP per 1000 person-days, as well as the mortality rate was 74 per 100 days, while the Attributable Risk Percentage (ARP) was 85%. This high fatality rate was clarified by independent predictors as reintubation (odds ratio [OR] = 8.99, P < 0.001), ICU duration ≥5 days (OR = 7.29, P = 0.02), HAP outcome (OR = 6.49, P = 0.001), diabetes mellitus (DM) (OR = 2.98, P = 0.004), APACHE II ≥17 (OR = 2.76, P = 0.004), as well as neurological diseases (OR = 2.20, P = 0.03). The most common independent HAP predictors were Pseudomonas aeruginosa (Hazard Ratio [HR] = 2.27, P < 0.001), Klebsiella pneumoniae (HR = 1.81, P = 0.003), tracheostomy (HR = 1.72, P = 0.04), and APACHE II ≥17 (HR = 1.54, P = 0.04).

CONCLUSION: High incidence rate of HAP was linked with P. aeruginosa, K. pneumoniae, tracheostomy, and APACHE II ≥17. Furthermore, a high mortality rate was strongly correlated with reintubation, duration in ICU ≥5 days, HAP outcome, DM, APACHE II ≥17, and neurological diseases.

PMID:36695229 | DOI:10.4103/aam.aam_178_21