Category: Statistics

Neuroimage. 2021 Nov 28:118749. doi: 10.1016/j.neuroimage.2021.118749. Online ahead of print.

ABSTRACT

Neurite orientation dispersion and density imaging (NODDI) estimates microstructural properties of brain tissue relating to the organisation and processing capacity of neurites, which are essential elements for neuronal communication. Descriptive statistics of NODDI tissue metrics are commonly analysed in regions-of-interest (ROI) to identify brain-phenotype associations. Here, the conventional method to calculate the ROI mean weights all voxels equally. However, this produces biased estimates in the presence of CSF partial volume. This study introduces the tissue-weighted mean, which calculates the mean NODDI metric across the tissue within an ROI, utilising the tissue fraction estimate from NODDI to reduce estimation bias. We demonstrate the proposed mean in a study of white matter abnormalities in young onset Alzheimer’s disease (YOAD). Results show the conventional mean induces significant bias that correlates with CSF partial volume, primarily affecting periventricular regions and more so in YOAD subjects than in healthy controls. Due to the differential extent of bias between healthy controls and YOAD subjects, the conventional mean under- or over-estimated the effect size for group differences in many ROIs. This demonstrates the importance of using the correct estimation procedure when inferring group differences in studies where the extent of CSF partial volume differs between groups. These findings are robust across different acquisition and processing conditions. Bias persists in ROIs at higher image resolution, as demonstrated using data obtained from the third phase of the Alzheimer’s disease neuroimaging initiative (ADNI); and when performing ROI analysis in template space. This suggests that conventional ROI means of NODDI metrics are biased estimates under most contemporary experimental conditions, the correction of which requires the proposed tissue-weighted mean. The tissue-weighted mean produces accurate estimates of ROI means and group differences when ROIs contain voxels with CSF partial volume. In addition to NODDI, the technique can be applied to other multi-compartment models that account for CSF partial volume, such as the free water elimination method. We expect the technique to help generate new insights into normal and abnormal variation in tissue microstructure of regions typically confounded by CSF partial volume, such as those in individuals with larger ventricles due to atrophy associated with neurodegenerative disease.

PMID:34852276 | DOI:10.1016/j.neuroimage.2021.118749

Bioresour Technol. 2021 Nov 28:126440. doi: 10.1016/j.biortech.2021.126440. Online ahead of print.

ABSTRACT

Detailed analysis of thermo-kinetics, reaction mechanism, and estimation of thermodynamic parameters are imperative for the design of reactor systems in thermochemical conversion processes. Present investigation was aimed at exploring the pyrolysis potential of pigeon pea stalk (PPS) by thermogravimetric experiments at 10, 20, and 30 °C/min heating rates. Maximum devolatilization of PPS was found to take place below 480 °C. The average activation energy for PPS pyrolysis was found to be 95.97, 100.74, 96.24, and 96.64 kJ/mol by Kissinger-Akahira-Sunose, Flynn-Wall-Ozawa, Starink, and Friedman method, respectively. Statistical analysis by one way analysis of variance method by employing Tukey test revealed that the difference in activation energy estimated from different methods was insignificant. Thermodynamic parameters (ΔH, ΔS_, and ΔG) together with reaction mechanisms were also evaluated. Difference in the activation energy and enthalpy was found to be <5 kJ/mol. R2 and R3 models were found best fitted with experimental PPS pyrolysis data.

PMID:34852283 | DOI:10.1016/j.biortech.2021.126440

Urology. 2021 Nov 28:S0090-4295(21)01096-7. doi: 10.1016/j.urology.2021.10.038. Online ahead of print.

ABSTRACT

OBJECTIVE: To determine the role of race in surgical outcomes of and complications after urethroplasty.

METHODS: A single institution, retrospective review was conducted from 2011-2019 on male patients ≥ 18 years of age who underwent urethroplasty. Exclusion criteria included previous urethral cancer, lack of follow up, or revision urethroplasty. Failure of urethroplasty was defined as requiring revision surgery or recurrence on imaging or cystoscopy. Risk factors for recurrence were determined using descriptive statistics, Wilcoxon comparisons, and multivariate logistic regression.

RESULTS: 307 patients were identified with 234 patients meeting inclusion criteria. 63.2% identified as White/Caucasian (CA), 32.5% Black/African American (AA), and 4.3% other race. Mean age was 49.4 years. Between CA and AA patients, there was no difference in mean age, BMI, smoking status, prior urethroplasty, or prior dilation/DVIU. CAs were more likely to have a fossa navicularis stricture compared to AAs (p=0.0094), but there were no significant differences in bulbar, penile, or posterior stricture rates (all p>0.05) or length (p=0.32). The overall stricture recurrence rate was 15.8% with a median of 242 days to recurrence and no significant difference by race for either outcome (p=0.83, p=.64). The only predictor of stricture recurrence was prior dilation/DVIU (p=0.0404, OR 2.3, 95% CI 1.0,5.6). Overall complication rate was 17.5%, with no difference between CA and AAs rates (p=0.83) or complication type (p=0.62).

CONCLUSIONS: There was no significant difference in the rate of surgical failure for urethral stricture repair based on race. The only predictor of surgical failure was having a prior urethral dilation/DVIU.

PMID:34852248 | DOI:10.1016/j.urology.2021.10.038

J Oral Maxillofac Surg. 2021 Nov 5:S0278-2391(21)01324-0. doi: 10.1016/j.joms.2021.10.014. Online ahead of print.

ABSTRACT

PURPOSE: Controversy exists among head and neck surgical specialties regarding management of Langerhan’s Cell Histiocytosis (LCH). The purpose of this study was to evaluate diagnosis, management, and treatment outcomes in children with LCH of the head and neck.

METHODS: This is a retrospective cohort study of children with LCH of the head and neck who presented to Children’s Healthcare of Atlanta hospital from 2009 to 2021. The independent variables were demographic information, lesion locations, clinical presentation, radiographic findings, diagnostic workup, treatment, and length of follow-up. The patients were grouped based on these variables. The outcome variable was disease reactivation. Descriptive statistics were calculated.

RESULTS: There were 3 presentations of LCH of the head and neck. Group 1 presented as a lesion in 1 system without CNS risk (SS-). There were 24 patients with an average age of 10 years. Lesions were located in calvaria and/or mandible. Majority of the patients were treated with only debridement. Two of the patients experienced reactivation. Group 2 presented as a lesion in 1 system with CNS risk (SS+). There were 30 patients with an average age of 6 years. Common locations were temporal bone and/or orbit. These patients present with recurrent ear infections and ptosis. Majority of the patients were treated with chemotherapy (n = 28). One patient had disease reactivation. Group 3 presented with multisystem involvement. There were 13 patients with an average age of 2 years. LCH was found in skin and the lymphatic system. Imagining demonstrated extracranial organ involvement. All of them were treated with chemotherapy. There was 40% reactivation of LCH.

CONCLUSIONS: Treatment of LCH depends on presentation. SS- subgroup can be adequately treated via surgical debridement. SS+ and multisystem groups benefit from an early disease diagnosis and require chemotherapy.

PMID:34852246 | DOI:10.1016/j.joms.2021.10.014

Sao Paulo Med J. 2021 Nov 29:S1516-31802021005028202. doi: 10.1590/1516-3180.2021.0111.R1.18052021. Online ahead of print.

ABSTRACT

BACKGROUND: Although autonomic dysfunction has been shown to be associated with liver cirrhosis, the prevalence and prognostic implications are unclear. Abnormal heart rate variability (HRV), a measure of autonomic function, has not been well investigated in cirrhosis.

OBJECTIVE: To evaluate the prevalence of high-risk HRV parameters in a cohort of cirrhotic patients and their association with cardiac dysfunction and mortality.

DESIGN AND SETTING: Prospective observational study conducted in the Federal University of São Paulo.

METHOD: A cohort of 120 patients, comprising 17 healthy controls and 103 cirrhotic outpatients, was evaluated and followed for 10 months. HRV analysis was based on 24-hour Holter monitoring and defined using time-domain and frequency-domain parameters.

RESULTS: The HRV parameters were statistically lower in cirrhotic patients than in healthy subjects. High-risk HRV parameters were prevalent, such that 64% had at least one high-risk parameter. Time-domain parameters correlated with Child scores (P < 0.0001). In regression models, HRV parameters were independent predictors of diastolic dysfunction and mortality. During 10 months of follow-up, there were 11 deaths, all of patients with at least one high-risk HRV parameter. Kaplan-Meier analysis estimated low survival rates among patients with standard deviation of normal-to-normal RR intervals (SDNN) < 100.

CONCLUSION: Reduced HRV is prevalent in liver cirrhosis and is related to cardiac dysfunction, severity of liver disease and mortality. Abnormal high-risk HRV parameters are prevalent among cirrhotic patients and are also predictors of mortality. Our findings highlight the need for a more careful cardiac evaluation of cirrhotic patients.

PMID:34852170 | DOI:10.1590/1516-3180.2021.0111.R1.18052021

Arch Cardiol Mex. 2021;91(4):396-406. doi: 10.24875/ACM.20000505.

ABSTRACT

BACKGROUND: Family psychotherapy has been shown to have a positive impact on the evolution of patients with psychosomatic disorders, and in those with arterial hypertension it could improve the level of control of the disease.

OBJECTIVE: To evaluate the impact of an intervention in family psychotherapy in patients with uncontrolled systemic arterial hypertension.

METHOD: Study with comparative groups. 15 uncontrolled hypertensive patients, assigned to 2 groups: an intervention group of 10 patients who received family psychotherapy and a control group of 5 patients. In both groups, the pharmacological treatment indicated by experts was continued. Both groups were compared before and after the intervention regarding quality of life (InCaViSa), family functioning (Family Functioning Scale), systolic and diastolic blood pressure, body mass index and glucose, cholesterol, triglycerides, uric acid and creatinine.

RESULTS: There was qualitative improvement in the domains of the InCaViSa scale to estimate quality of life in the intervention group and there were no statistically significant changes between the groups in family functioning or in body weight. Among the biochemical variables, only cholesterol showed a significant reduction (p = 0.47). Greater mobility of the family towards more functional behaviors was found in the group that received the intervention, and also in this group, systolic and diastolic blood pressure values decreased (p < 0.001), and the use of antihypertensive, anxiolytic and antidepressant drugs, as well.

CONCLUSIONS: Family psychotherapeutic intervention can favor the control of blood pressure, reduce the doses of antihypertensive, anxiolytic and antidepressant drugs and it can help to transition to better functionally family states.

PMID:34852188 | DOI:10.24875/ACM.20000505

J Appl Oral Sci. 2021 Nov 29;29:e20210171. doi: 10.1590/1678-7757-2021-0171. eCollection 2021.

ABSTRACT

Some evidence in vitro suggested that amoxicillin and fluoride could disturb the enamel mineralization.

OBJECTIVE: To assess the effect of amoxicillin and of the combination of amoxicillin and fluoride on enamel mineralization in rats.

METHODOLOGY: In total, 40 rats were randomly assigned to four groups: control group (CG); amoxicillin group (AG – amoxicillin (500 mg/kg/day), fluoride group (FG – fluoridated water (100 ppm -221 mg F/L), and amoxicillin + fluoride group (AFG). After 60 days, the samples were collected from plasma and tibiae and analyzed for fluoride (F) concentration. The incisors were also collected to determine the severity of fluorosis using the Dental Fluorosis by Image Analysis (DFIA) software, concentration of F, measurements of enamel thickness, and hardness. The data were analyzed by ANOVA, Tukey’s post-hoc test, or Games-Howell post-hoc test (α=0.05).

RESULTS: Enamel thickness of the incisors did not differ statistically among the groups (p=0.228). Groups exposed to fluoride (AFG and FG) have higher F concentrations in plasma, bone and teeth than those not exposed to fluoride (CG and AG). The groups showed a similar behavior in the DFIA and hardness test, with the FG and AFG groups showing more severe fluorosis defects and significant lower hardness when compared with the AG and CG groups, with no difference from each other.

CONCLUSION: The rats exposed to fluoride or fluoride + amoxicillin developed dental fluorosis, while exposure to amoxicillin alone did not lead to enamel defects.

PMID:34852156 | DOI:10.1590/1678-7757-2021-0171

Sao Paulo Med J. 2021 Nov 29:S1516-31802021005028201. doi: 10.1590/1516-3180.2020.0718.R1.18052021. Online ahead of print.

ABSTRACT

BACKGROUND: Dengue is considered to be the most important arbovirus worldwide, with important complications that increase its lethality. In Brazil, an endemic country, the disease reaches significant incidence levels, with occurrences of serious cases and high costs of hospitalizations for its treatment.

OBJECTIVE: To analyze risk factors among individuals with recent histories of dengue infection in a medium-sized city in Mato Grosso.

DESIGN AND SETTING: Descriptive cross-sectional study, of epidemiological-survey type, conducted among the urban population of a city located in mid-northern Mato Grosso.

METHODS: A seroepidemiological survey using questionnaires and collection of biological material was conducted among 596 adults aged ≥ 18 years who had been selected through a cluster sampling process. Positive dengue cases were those with positive results from anti-dengue immunoassays (ELISA). Statistical analyses with descriptive and inferential techniques were used, with 95% confidence intervals and a 5% significance level.

RESULTS: The seroepidemiological profile of the study participants was predominantly female, with ages between 18 and 39 years, self-declared non-white race/color, not more than eight years of education and not living with a companion. Among the sanitary factors analyzed, the following were risk factors for dengue virus infection: no running water at home; no water supply from the public piped network; no waste from drains or toilets sent to the sewage network; endemic disease combat agents visiting the home; and presence of mosquito breeding sites at home.

CONCLUSION: Low schooling levels and previous dengue virus infection were associated with current dengue virus infection.

PMID:34852169 | DOI:10.1590/1516-3180.2020.0718.R1.18052021

Rev Bras Enferm. 2021 Nov 29;75(3):e20210407. doi: 10.1590/0034-7167-2021-0407. eCollection 2021.

ABSTRACT

OBJECTIVES: to identify factors associated with specific health-related quality of life in cerebrovascular accident, or stroke, survivors.

METHODS: cross-sectional study, carried out with 160 cerebrovascular accident survivors. Data were collected using the Barthel Index, Cerebrovascular Accident Specific Quality of Life Scale, and semi-structured instruments for sociodemographic and clinical data, analyzed by descriptive and inferential statistics.

RESULTS: health-related quality of life was associated with work activity (p=0.027), physical activity (p=0.007), functional capacity (p=0.001), presence of caregiver (<0.001), motor alteration (p = 0.001) and rehabilitation (p=0.003). The functionally dependent people were 14.61 times more likely to present low health-related quality of life, and those with motor impairment were 3.07 times more likely.

CONCLUSIONS: it was evidenced that functional dependence and motor impairment increase the chance of low health-related quality of life in cerebrovascular accident survivors.

PMID:34852127 | DOI:10.1590/0034-7167-2021-0407

Rev Bras Enferm. 2021 Nov 29;75(3):e20210316. doi: 10.1590/0034-7167-2021-0316. eCollection 2021.

ABSTRACT

OBJECTIVES: to evaluate the completeness of nurses’ records on the execution of the nursing process in assistance of tuberculosis patients at Primary Care.

METHODS: this was a retrospective documental study, with 190 records in Family Health Units of a city in the state of Paraíba. The data were analyzed according to descriptive statistics, Pareto Diagram, and trend analysis.

RESULTS: the overall mean incompleteness of records was 53.01% (DP=26.13). Therefore, the results presented very poor completeness classification related to nursing diagnosis (88.9%), nursing assessment (66.8%), data collection (60.5%), while nursing interventions were classified as regular (11.1%). The nursing diagnosis was the only variable with a decreasing trend of non-completeness.

CONCLUSIONS: incompleteness of nurses’ records in the medical records of users with tuberculosis. Evaluation strategies, permanent and continuing education are indispensable in the quality of nurses’ documentation, directly implying the Systematization of Quality in Nursing Care.

PMID:34852125 | DOI:10.1590/0034-7167-2021-0316