Categories
Nevin Manimala Statistics

The effect of multiplanar loading on the intradiscal pressure of the whole human spine: systematic review and meta-analysis

Eur Cell Mater. 2021 Mar 21;41:388-400. doi: 10.22203/eCM.v041a25.

ABSTRACT

For spinal load and muscle force estimation as well as for numerical model and experimental setup validation, data on human intradiscal pressure are essential. Therefore, the aim of the present meta-analysis was to summarise all in vitro measurements of human intradiscal pressure performed under defined boundary conditions, i.e. without external loading (intrinsic pressure), under axial loading (compression, traction, shear) and under single-planar bending loading (flexion, extension, lateral bending, axial rotation). Data were evaluated based on segmental level and normalised to force and moment. Regression analysis was performed to investigate coefficients of determination and statistical significance of relationships between intradiscal pressure and segmental level for the single loading conditions. 35 studies fulfilled the inclusion criteria, from which a total of 451 data points were collected for the meta-analysis. High coefficients of determination were found in axial compression (r2 = 0.875) and flexion (r2 = 0.781), while being low for intrinsic pressure (r2 = 0.266) and lateral bending (r2 = 0.385), all showing significant regression fitting (p < 0.01). Intradiscal pressure decreases from the upper cervical spine to the sacrum in all loading conditions, considering the same amount of loading for all segmental levels, while the intrinsic pressure exhibits a minimum of the regression curve in the mid-thoracic spine. Apart from its potential for numerical and experimental model validation, this dataset may help to understand the load distribution along the human spine.

PMID:33745125 | DOI:10.22203/eCM.v041a25

Categories
Nevin Manimala Statistics

Efficacy and safety of neoadjuvant immune checkpoint inhibitors in early-stage triple-negative breast cancer: a systematic review and meta-analysis

J Cancer Res Clin Oncol. 2021 Mar 21. doi: 10.1007/s00432-021-03591-w. Online ahead of print.

ABSTRACT

PURPOSE: There is uncertainty regarding the role of adding immune checkpoint inhibitors (ICIs) to neoadjuvant chemotherapy (NACT) in early-stage triple-negative breast cancer (TNBC).

METHODS: We identified randomized controlled trials (RCTs) comparing ICIs combined with NACT to NACT in early-stage TNBC. Efficacy outcomes included pathological complete response (pCR) and event-free survival (EFS). Toxicity data included any grade 3/4 adverse events (AEs), serious AEs, AEs leading to death, common and meaningful AEs associated with chemotherapy and immune-related AEs. Odds ratio (ORs), hazard ratios (HR) and their respective 95% confidence intervals (CI) for efficacy and toxicity were extracted and pooled in a meta-analysis. Differences in the odds for pCR between programmed death ligand 1 (PD-L1) status and between PD-L1 and PD-1 inhibitors were also assessed.

RESULTS: Five RCTs comprising 2,075 patients were analyzed. Compared to NACT alone, combination of ICIs and NACT significantly improved pCR (OR 1.75, 95% CI 1.25-2.47, p = 0.001) and EFS (HR 0.66, 95% CI 0.48-0.91, p = 0.01). Magnitude of effect on pCR was similar between PD-L1-positive and PD-L1-negative tumors (p for the subgroup difference = 0.80) and between PD-L1 and PD-1 inhibitors (p = 0.27). The combination treatment resulted in higher odds of any grade 3/4 AEs (OR 1.31, p = 0.02) and serious AEs (OR 1.84, p = 0.006), with no statistically significant difference in AEs leading to death (OR 1.67, p = 0.51). Higher magnitude of toxicity was observed for immune-related AEs.

CONCLUSION: Combination of ICIs and NACT were associated with improved outcome in early-stage TNBC while increasing toxicity significantly. Longer follow-up is desired to better understand the risk and benefit ratio of this combination.

PMID:33745080 | DOI:10.1007/s00432-021-03591-w

Categories
Nevin Manimala Statistics

Effects of COVID-19 on the admissions of aneurysmal subarachnoid hemorrhage: the West Greece experience

Neurol Sci. 2021 Mar 21. doi: 10.1007/s10072-021-05190-6. Online ahead of print.

ABSTRACT

BACKGROUND: Acute subarachnoid hemorrhage (SAH) due to aneurysmal rupture is a devastating vascular disease accounting for 5% of strokes. COVID-19 pandemic resulted in a decrease in elective and emergency admissions in the majority of neurosurgical centers. The main hypothesis was that fear of COVID-19 may have prevented patients with critical medical or surgical emergencies from actively presenting in emergency departments and outpatient clinics.

METHODS: We conducted a single-center, retrospective, observational study searching our institutional data regarding the incidence of spontaneous subarachnoid hemorrhage (SAH) and compare the admissions in two different periods: the pre COVID-19 with the COVID-19 period.

RESULTS: The study cohort was comprised of a total of 99 patients. The mean (SD) weekly case rate of patients with SAH was 1.1 (1.1) during the pre-COVID-19 period, compared to 1.7 (1.4) during the COVID-19 period. Analysis revealed that the volume of admitted patients with SAH was 1.5-fold higher during the COVID period compared to the pre-COVID period and this was statistically significant (ExpB = 1.5, CI 95% 1-2.3, p = 0.044). Difference in mortality did not reach any statistical significance between the two periods (p = 0.097), as well as patients’ length of stay (p = 0.193).

CONCLUSIONS: The presented data cover a more extended time period than so far published reports; it is reasonable that our recent experience may well be demonstrating a general realistic trend of overall increase in aneurysmal rupture rates during lockdown. Hospitalization of patients with SAH cannot afford any reductions in facilities, equipment, or personnel if optimum outcomes are desirable.

PMID:33745041 | DOI:10.1007/s10072-021-05190-6

Categories
Nevin Manimala Statistics

Per- and polyfluoroalkyl substances (PFASs) in Swedish household dust and exposure of pet cats

Environ Sci Pollut Res Int. 2021 Mar 20. doi: 10.1007/s11356-021-13343-5. Online ahead of print.

ABSTRACT

Per- and polyfluoroalkyl substances (PFASs) are used in a wide range of products and have been found ubiquitously in our indoor environment, and there is evidence that exposure to PFAS can lead to adverse endocrine effects, such as thyroid hormone disruption. Pet cats have a high dust intake due to their grooming behavior and have been shown to be a suitable sentinel species for assessment of toddler’s exposure. Here we used paired household dust (n=46) and cat serum (n=27) samples to establish whether dust is a relevant exposure pathway to PFASs. An analytical method for PFAS analysis was optimized using a low volume of cat serum samples, combining solid-phase extraction and online sample cleanup. Dust was extracted with methanol by sonication and cleaned up by addition of active carbon. In total, 27 PFASs were analyzed by liquid chromatography/mass spectrometry analysis. The correlation between PFAS levels in dust and serum, serum lipids and thyroid hormone levels, and PFAS levels in dust between different rooms were statistically evaluated. PFOS and PFDA could be quantified in all cat serum samples (median 2300 pg/mL and 430 pg/mL, respectively), followed by PFOA (median 1100 pg/mL), quantified in 96% of the samples. The levels of 6:2 and 8:2 diPAPs were determined in 65% and 92% of the serum samples, respectively, and were an order of magnitude lower (1.4-160 pg/mL). Household dust on the other hand was dominated by 6:2 and 8:2 diPAPs, with a median of 65 ng/g dust and 49 ng/g dust, respectively. PFOS (median 13 ng/g dust) and PFOA (median 9 ng/g dust) were quantified in 93% of the dust samples. Only eight PFASs were detected (>LOD) in at least 50% of the samples of both matrices and could be paired. Significant correlations between cat serum and dust were found for PFOA (rS=0.32, p<0.049) and PFUnDA (rS=0.55, p<0.001). Significant positive correlations were found between serum total thyroxine (rS=0.11, p<0.05) and PFNA and between serum cholesterol and PFHpA (rS=0.46, p<0.01), PFUnDA (rS=0.40, p<0.05), PFDoDA (rS=0.44, p<0.01), and sum PFAS (rS=0.48, p<0.01). In conclusion, this study confirmed that dust is a relevant exposure pathway for the ingestion of some PFASs for cats, and the serum levels of PFASs could be of relevance for the cat’s health.

PMID:33745045 | DOI:10.1007/s11356-021-13343-5

Categories
Nevin Manimala Statistics

Revisiting Co-Trimoxazole Prophylaxis for African Adults in The Era of Antiretroviral Therapy: A Randomized Controlled Clinical Trial

Clin Infect Dis. 2021 Mar 21:ciab252. doi: 10.1093/cid/ciab252. Online ahead of print.

ABSTRACT

BACKGROUND: Daily co-trimoxazole is recommended for African adults living with HIV irrespective of antiretroviral treatment, immune status, or disease stage. Benefits of continued prophylaxis and whether co-trimoxazole can be stopped following immune reconstitution are unknown.

METHODS: We conducted a randomized, controlled trial at two sites in Malawi that enrolled HIV-infected adults with undetectable viral load and CD4 count of >250/mm 3 and randomized them to continue daily co-trimoxazole, discontinue daily co-trimoxazole and begin weekly chloroquine, or discontinue daily co-trimoxazole. The primary endpoint was the preventive effect of co-trimoxazole prophylaxis against death or World Health Organization (WHO) HIV/AIDS Stage 3-4 events, using Cox proportional hazards modelling, intention to treat population.

RESULTS: 1499 adults were enrolled. The preventive effect of co-trimoxazole on the primary endpoint was 22% (95%CI -14-47%, p=0.20) versus no prophylaxis and 25% (95%CI -10-48%, p=0.14) versus chloroquine. When WHO HIV/AIDS Stage 2 events were added to the primary endpoint, preventive effect increased to 31% (95%CI 3-51%, p=0.032) and 32% (95%CI 4-51%, p=0.026), respectively. Co-trimoxazole and chloroquine prophylaxis effectively prevented clinical malaria episodes (3.8 and 3.0, respectively, versus 28/100 person-years, p<0.001).

CONCLUSIONS: Malawian adults living with HIV who immune reconstituted on ART and continued co-trimoxazole prophylaxis experienced fewer deaths and WHO HIV/AIDS Stage 3-4 events compared to prophylaxis discontinuation, though statistical significance was not achieved. Cotrimoxazole prevented a composite of death plus WHO HIV/AIDS Stage 2-4 events. Given poor healthcare access and lack of routine viral load monitoring, co-trimoxazole prophylaxis should continue in adults on ART after immune reconstitution in sub-Saharan Africa.

PMID:33744963 | DOI:10.1093/cid/ciab252

Categories
Nevin Manimala Statistics

No decrease in incidence of arthroscopic meniscectomy in a Canadian province

Knee Surg Sports Traumatol Arthrosc. 2021 Mar 21. doi: 10.1007/s00167-021-06534-7. Online ahead of print.

ABSTRACT

PURPOSE: Arthroscopic meniscectomy (APM) is the most common procedure in orthopedic surgery, despite increasing evidence questioning its benefit over conservative management for treatment of degenerative meniscal tears. The purpose of this study is to determine the epidemiology and trends of APM in Saskatchewan, a Canadian province, over a 20 year period.

METHODS: Physician billing codes were used to identify patients who underwent APM in Saskatchewan between January 1, 1998 and December 31, 2017. Records were obtained from eHealth Saskatchewan, a provincial health database. Data was analyzed for overall incidence and age-specific trends of APM.

RESULTS: A total of 35,099 APMs were performed during the study period. The population of Saskatchewan ranged from 992,314 to 1,150,782 (median 1,017,368) during this time interval, with 81 orthopedic surgeons performing APM. Overall incidence rate of APM did not change significantly over time. No decrease was observed in patients presumed to have degenerative tears (≥ 50 years). The number of meniscectomies in patients ≥ 50 years was significantly greater during the second decade of study compared to the first (OR 1.48, p < 0.01). Conversely, the increase in incidence rate among older patients was not statistically significant (R2 = 0.125, n.s.).

CONCLUSION: Overall incidence rate of APM in Saskatchewan has not decreased during the last 20 years. Furthermore, APM frequency increased over time for individuals ≥ 50 years. Several regional factors may have contributed to these findings, including the large proportion of Saskatchewan residents engaged in physically demanding work and barriers to accessing physiotherapy services. Given recent evidence disputing the benefit of APM over conservative measures, this study highlights the need for improved dissemination of evidence, as well as the importance of an individualized treatment plan to address patient-specific factors.

LEVEL OF EVIDENCE: Level IV.

PMID:33745007 | DOI:10.1007/s00167-021-06534-7

Categories
Nevin Manimala Statistics

Threshold effects of capital investments on carbon emissions in G20 economies

Environ Sci Pollut Res Int. 2021 Mar 21. doi: 10.1007/s11356-021-13046-x. Online ahead of print.

ABSTRACT

Investment in capitals is sacrosanct to launch a country to a greater path of sustainable development. Notwithstanding, its deleterious impacts on environment are equally incontestable. In light of this stark reality, this paper examines the threshold effects of capital investments on carbon emissions in G20 economies over the period, 1992-2014, for which data are available. The study uses both exogenously determined and endogenously determined thresholds to uncover the relationship. While the former relies on median approach to determining the threshold on the one hand, the latter uses both the fixed effects panel threshold model proposed by (Hansen J Econ 93:345-368, 1999) and the bootstrap method by (Hansen Econometrica 68:575-603, 2000) to assess the statistical relevance of the threshold effects on the other hand. The results of the exogenously determined thresholds show higher statistical significant environmental impacts of capital investments at a median threshold of above 3.068 than when it is lesser. The findings of the latter approach indicate the relationship between capital investments and carbon emissions to be non-linear for the G20 countries. More specifically, this study establishes a single-threshold level of capital investment on carbon emissions for the group of countries. The threshold estimator of 3.434 is established at the 95% confidence interval. Beyond this point, the environmental impacts of capital investments are imaginable. On the policy front, keeping to the limit set by threshold effects would go a long way to stemming environmental pollution and mitigating climatic change impacts.

PMID:33745025 | DOI:10.1007/s11356-021-13046-x

Categories
Nevin Manimala Statistics

Uptake of hysterectomy and bilateral salpingo-oophorectomy in carriers of pathogenic mismatch repair variants: a Prospective Lynch Syndrome Database report

Eur J Cancer. 2021 Mar 17;148:124-133. doi: 10.1016/j.ejca.2021.02.022. Online ahead of print.

ABSTRACT

PURPOSE: This study aimed to report the uptake of hysterectomy and/or bilateral salpingo-oophorectomy (BSO) to prevent gynaecological cancers (risk-reducing surgery [RRS]) in carriers of pathogenic MMR (path_MMR) variants.

METHODS: The Prospective Lynch Syndrome Database (PLSD) was used to investigate RRS by a cross-sectional study in 2292 female path_MMR carriers aged 30-69 years.

RESULTS: Overall, 144, 79, and 517 carriers underwent risk-reducing hysterectomy, BSO, or both combined, respectively. Two-thirds of procedures before 50 years of age were combined hysterectomy and BSO, and 81% of all procedures included BSO. Risk-reducing hysterectomy was performed before age 50 years in 28%, 25%, 15%, and 9%, and BSO in 26%, 25%, 14% and 13% of path_MLH1, path_MSH2, path_MSH6, and path_PMS2 carriers, respectively. Before 50 years of age, 107 of 188 (57%) BSO and 126 of 204 (62%) hysterectomies were performed in women without any prior cancer, and only 5% (20/392) were performed simultaneously with colorectal cancer (CRC) surgery.

CONCLUSION: Uptake of RRS before 50 years of age was low, and RRS was rarely undertaken in association with surgical treatment of CRC. Uptake of RRS aligned poorly with gene- and age-associated risk estimates for endometrial or ovarian cancer that were published recently from PLSD and did not correspond well with current clinical guidelines. The reasons should be clarified. Decision-making on opting for or against RRS and its timing should be better aligned with predicted risk and mortality for endometrial and ovarian cancer in Lynch syndrome to improve outcomes.

PMID:33743481 | DOI:10.1016/j.ejca.2021.02.022

Categories
Nevin Manimala Statistics

Genetic-fuzzy logic model for a non-invasive measurement of a stroke volume

Comput Methods Programs Biomed. 2021 Mar 12;203:106046. doi: 10.1016/j.cmpb.2021.106046. Online ahead of print.

ABSTRACT

BACKGROUND: Despite the importance of stroke volume readings in understanding the work of the cardiovascular system in patients, its routine daily measurement outside of a hospital in the absence of special equipment presents a problem for a comprehensive assessment of the heart performance.

OBJECTIVE: The purpose of this study was to develop a new non-invasive technique for measuring a stroke volume based on the relationship between time skin warming and a blood flow.

METHODS: . Ninety two randomly selected volunteers (54 males, aged 30.1 ± 11.9 years old, and 38 females, aged 35.8 ± 12.4 years old) were recruited for this study. The time skin warming was determined by applying on the wrist above the arterial pulsation a thermoelectric cooler using the Peltier effect. During recording the participants were in the supine position. Blood pressure was measured by sphygmomanometer. Heart performance was assessed by Murata ballistocardiographic sensor, detecting displacement of the whole body during each cardiac ejection of blood. The data provided by this sensor included heart rate, respiratory rate, heart rate variability and a stroke volume. Linear, non-linear statistical regression models and fuzzy logic were used to analyse the degree of interrelation between BCG-measured stroke volume and the time skin warming.

RESULTS: Comparative analysis of results indicated that the generic-fuzzy logic model demonstrated a high level of dependency (R = 0.803) between input (participants’ time skin warming, pulse pressure and age) and output (ballistocardiographic stroke volume) parameters.

CONCLUSIONS: The method described in the paper offers a simple, portable, and low-cost solution that can even be used in a home setting to measure the stroke volume. The principle of the proposed method is based on the interrelation between time skin warming and blood flow. The latter, corrected by corresponding age and pulse pressure, expresses the participant’s stroke volume. Adopting the genetic-fuzzy model significantly improved the accuracy of stroke volume’s measurement and made the proposed method reliable for assessing of the cardiovascular system. This daily practice technique would help healthcare provider get an early diagnosis of cardiac dysfunctions and track heart changes during stress, e.g., in sport.

PMID:33743490 | DOI:10.1016/j.cmpb.2021.106046

Categories
Nevin Manimala Statistics

Fitting unbranching skeletal structures to objects

Med Image Anal. 2021 Mar 4;70:102020. doi: 10.1016/j.media.2021.102020. Online ahead of print.

ABSTRACT

Representing an object by a skeletal structure can be powerful for statistical shape analysis if there is good correspondence of the representations within a population. Many anatomic objects have a genus-zero boundary and can be represented by a smooth unbranching skeletal structure that can be discretely approximated. We describe how to compute such a discrete skeletal structure (“d-s-rep”) for an individual 3D shape with the desired correspondence across cases. The method involves fitting a d-s-rep to an input representation of an object’s boundary. A good fit is taken to be one whose skeletally implied boundary well approximates the target surface in terms of low order geometric boundary properties: (1) positions, (2) tangent fields, (3) various curvatures. Our method involves a two-stage framework that first, roughly yet consistently fits a skeletal structure to each object and second, refines the skeletal structure such that the shape of the implied boundary well approximates that of the object. The first stage uses a stratified diffeomorphism to produce topologically non-self-overlapping, smooth and unbranching skeletal structures for each object of a population. The second stage uses loss terms that measure geometric disagreement between the skeletally implied boundary and the target boundary and avoid self-overlaps in the boundary. By minimizing the total loss, we end up with a good d-s-rep for each individual shape. We demonstrate such d-s-reps for various human brain structures. The framework is accessible and extensible by clinical users, researchers and developers as an extension of SlicerSALT, which is based on 3D Slicer.

PMID:33743355 | DOI:10.1016/j.media.2021.102020