Category: Statistics

Scientifica (Cairo). 2021 Sep 15;2021:9316277. doi: 10.1155/2021/9316277. eCollection 2021.

ABSTRACT

INTRODUCTION: Hypoxic-ischemic encephalopathy (HIE) is defined as a neurological complication that results from perinatal asphyxia. Previous studies had investigated various markers to early detect HIE; however, these markers appeared to have several drawbacks, especially in resource-limited settings.

AIM: This study aimed at evaluating the predictive value of the salivary lactate dehydrogenase level as a potential predictor of hypoxic-ischemic encephalopathy for newborns.

MATERIALS AND METHODS: We included 30 neonates with HIE due to perinatal asphyxia and 30 healthy newborns that serve as controls, admitted at the intensive care unit for neonates and maternity ward at Ismailia area Clinics and Hospitals. We measured the LDH levels by using saliva samples that were collected for neonates maximum by 12 h after birth.

RESULTS: It was found that patients with HIE had a statistically significant higher salivary LDH level (1927 ± 390.3 IU/L) than patients without HIE (523.6 ± 142.8 IU/L) (p < 0.001). Moreover, salivary LDH showed a good discriminative ability where the AUC was 0.966 regarding salivary LDH (95% CI: 0.917-1.0) (p < 0.001). The best cutoff value was 1420 IU/L or more which showed the best results in predicting the occurrence of HIE with 98.3% and 97.6% sensitivity and specificity, respectively.

CONCLUSION: Salivary LDH can be considered as a useful noninvasive laboratory marker that can accurately predict HIE incidence among neonates with asphyxia within 12 hours from birth. The cases in the HIE group were assigned into three stages according to the Sarnat and Sarnat staging system: stage I: mild (irritable, normal, or hypertonia and poor feeding); stage II: moderate (lethargy, hypotonia, and frequent seizure); stage III: severe (coma, flaccid, absent reflexes, and frequent seizure). There is a positive association between LDH levels and the severity of HIE.

PMID:34567822 | PMC:PMC8457975 | DOI:10.1155/2021/9316277

Int J Surg Oncol. 2021 Sep 16;2021:8290659. doi: 10.1155/2021/8290659. eCollection 2021.

ABSTRACT

AIM: To evaluate the clinicopathological features affecting the recurrence and survival of 9 cases of neuroendocrine cancer of the cervix.

METHOD: We retrospectively analyzed 9 cervical neuroendocrine cancer cases identified among 453 cervical cancer patients between 2004 and 2021 at Akdeniz University Gynecological Oncology Outpatient Clinic. Kaplan-Meier survival analysis was used for progression-free survival (PFS) and overall survival (OS). Mathematical functions of mean, standard deviation, median, Min-Max values, and frequencies were used for descriptive statistics. The categorical data were expressed in numbers and percentages (%).

RESULTS: Nine patients with neuroendocrine histological subtype were selected out of 453 patients diagnosed with cervical cancer (1.98%). The average overall survival time of the patients was 26 months. The 5-year survival rate was 53.3%, while the PFS was 62.5%. The most common subtype was small cell neuroendocrine cancer. Tumours were mostly locally advanced at the time of diagnosis. 3 patients’ stage was 1b2, while 4 patients were 2b, 1 patient was 3c2r, and 1 patient was 4b. All tumours showed the immunohistochemical staining properties of neuroendocrine cancer. The main treatment modality applied to our patients was surgery + adjuvant CRT. The most used chemotherapeutic agents were cisplatin/carboplatin and etoposide. Recurrence was found in 3 cases, including 5 deaths.

CONCLUSION: Neuroendocrine tumour of the cervix is a rare subtype with a poor prognosis. Unfortunately, there is not yet a standard treatment protocol due to the limited number of comparative studies of surgery, chemotherapy, and radiotherapy based treatment schemes.

PMID:34567803 | PMC:PMC8463196 | DOI:10.1155/2021/8290659

Atmosphere (Basel). 2021 Aug 14;12(8):1-1044. doi: 10.3390/atmos12081044.

ABSTRACT

Reducing PM_2.5 and ozone concentrations is important to protect human health and the environment. Chemical transport models, such as the Community Multiscale Air Quality (CMAQ) model, are valuable tools for exploring policy options for improving air quality but are computationally expensive. Here, we statistically fit an efficient polynomial function in a response surface model (pf-RSM) to CMAQ simulations over the eastern U.S. for January and July 2016. The pf-RSM predictions were evaluated using out-of-sample CMAQ simulations and used to examine the nonlinear response of air quality to emission changes. Predictions of the pf-RSM are in good agreement with the out-of-sample CMAQ simulations, with some exceptions for cases with anthropogenic emission reductions approaching 100%. NO_X emission reductions were more effective for reducing PM_2.5 and ozone concentrations than SO₂, NH₃, or traditional VOC emission reductions. NH₃ emission reductions effectively reduced nitrate concentrations in January but increased secondary organic aerosol (SOA) concentrations in July. More work is needed on SOA formation under conditions of low NH₃ emissions to verify the responses of SOA to NH₃ emission changes predicted here. Overall, the pf-RSM performs well in the eastern U.S., but next-generation RSMs based on deep learning may be needed to meet the computational requirements of typical regulatory applications.

PMID:34567797 | PMC:PMC8459679 | DOI:10.3390/atmos12081044

J Ophthalmol. 2021 Sep 16;2021:5860846. doi: 10.1155/2021/5860846. eCollection 2021.

ABSTRACT

PURPOSE: To compare simulated and total keratometry and corneal astigmatism values between the IOLMaster 700 and Galilei G4 devices.

METHODS: A retrospective chart review was conducted for all patients undergoing phacoemulsification by a single surgeon (RTP) from March through September 2020 and who underwent imaging with both the IOLMaster 700 and Galilei G4. Exclusion criteria were prior corneal surgery, keratectatic diseases and inability to obtain a reliable image during image acquisition. Mean, flat, and steep keratometry values as well as astigmatism magnitude were compared.

RESULTS: A total of 200 eyes of 100 patients were included. Intraclass correlation coefficients (ICC) were moderate or high for all variables. Mean difference ± SD in SimK and TrueK between devices (G4-IOLM) was 0.05 ± 0.318 diopters and -1.1156 ± 0.438 diopters, respectively (p < 0.05 for both). The IOLM measured steeper TrueK value than the G4. For SimK, there was a statistically significant difference between devices only for mean keratometry (K), whereas for TrueK, there were significant differences in flat K, steep K, and mean K. Astigmatism analysis revealed a difference in mean (±SD) SimK of 0.07 (±0.57) D at 94 degrees and in mean TrueK of 0.04 (±0.85) D at 108 degrees.

CONCLUSION: Though there is overall good correlation between the IOLMaster 700 and Galilei G4 in SimK and astigmatism measurements, there is a significant difference in TrueK measurements, with the IOLM measuring steeper values by about 1.0 diopter as compared to the G4.

PMID:34567799 | PMC:PMC8460384 | DOI:10.1155/2021/5860846

Microsyst Nanoeng. 2020 Oct 5;6:82. doi: 10.1038/s41378-020-00187-1. eCollection 2020.

ABSTRACT

We report on the development of a microfluidic multiplexing technology for highly parallelized sample analysis via quantitative polymerase chain reaction (PCR) in an array of 96 nanoliter-scale microcavities made from silicon. This PCR array technology features fully automatable aliquoting microfluidics, a robust sample compartmentalization up to temperatures of 95 °C, and an application-specific prestorage of reagents within the 25 nl microcavities. The here presented hybrid silicon-polymer microfluidic chip allows both a rapid thermal cycling of the liquid compartments and a real-time fluorescence read-out for a tracking of the individual amplification reactions taking place inside the microcavities. We demonstrate that the technology provides very low reagent carryover of prestored reagents < 6 × 10^-2 and a cross talk rate < 1 × 10^-3 per PCR cycle, which facilitate a multi-targeted sample analysis via geometric multiplexing. Furthermore, we apply this PCR array technology to introduce a novel digital PCR-based DNA quantification method: by taking the assay-specific amplification characteristics like the limit of detection into account, the method allows for an absolute gene target quantification by means of a statistical analysis of the amplification results.

PMID:34567692 | PMC:PMC8433415 | DOI:10.1038/s41378-020-00187-1

J Hip Preserv Surg. 2021 May 11;8(1):83-89. doi: 10.1093/jhps/hnab035. eCollection 2021 Jan.

ABSTRACT

Iliopsoas impingement is an underdiagnosed cause of groin pain after total hip arthroplasty (THA), being responsible for 4.4% of cases. Non-surgical treatment may be effective in ∼50% of cases. Endoscopic surgery has gained popularity as an option for non-responsive patients because of its non-invasive characteristics, faster recovery and encouraging results. This study compares two different sites of endoscopic psoas tenotomy performed following THA: at the edge of the acetabulum (AR) versus at the lesser trochanter (LT). This is a retrospective review of prospectively collected data from a single-surgeon case series. Thirty-five iliopsoas tenotomy cases which had >24-month follow-up were identified. There were 21 tenotomies at the lesser trochanter. Demographic data, preop and postop pain, mHHS and NAHS scores, strength and patient satisfaction data were collected and analysed. Average age at the time of surgery was 62. Mean follow-up for the LT group was 49.11 months and 42.42 months for the AR group. Pain decreased significantly for both groups (P < 0.001). Both mHHS and NAHS showed superiority in the LT group, but this difference did not reach significance (P = 0.06). LT patients showed better strength with 71.42% of them having normal strength at latest follow-up, compared with 41.6% in the AR group. There were no complications in either group. Endoscopic tenotomy is a safe and reliable surgical option, giving significant pain relief and good functional outcomes. Tenotomy at the level of the lesser trochanter might be preferable since it shows better outcomes. Larger studies are necessary to achieve statistically significant results.

PMID:34567604 | PMC:PMC8460172 | DOI:10.1093/jhps/hnab035

J Hip Preserv Surg. 2021 Jul 31;8(1):22-27. doi: 10.1093/jhps/hnab002. eCollection 2021 Jan.

ABSTRACT

ChondroFiller gel is an absorbable collagen implant. It serves as a protective cover for the cartilage defects, allowing chondrocyte migration into the lesion. The implant consists of collagen (Type I) and is derived from veterinary monitored rats. This study evaluates the use of ChondroFiller gel in the treatment of cartilage lesions during hip joint arthroscopy. A prospective study was conducted on a group of 26 adult patients. All patients had an existing femoroacetabular impingement together with acetabular cartilage lesions >2 cm². All patients underwent hip arthroscopic surgery and the lesions were treated using ChondroFiller gel. The cartilage tissue healing was evaluated postoperatively using MRI. A total of 26 patients, including 5 females and 21 males, all with articular cartilage lesions, were included in the study. Cartilage healing conditions were evaluated for all patients, and the difference between pre- and post-surgery conditions was statistically significant. The follow-up scores have been acquired from 21 out of initial 26 patients (2 were disqualified after receiving THR, 3 could not be reached by researchers) after 3, 4 and 5 years consecutively with 17/21 patients having good/excellent results. The use of ChondroFiller gel during arthroscopy of the hip for acetabular cartilage lesions is an effective treatment technique. Encouraging long-term results have been observed, but further research on larger group of patient is required to better assess the full value of this technique. Patients with pre-existing osteoarthritis (Tönnis 2-3) have poor results.

PMID:34567597 | PMC:PMC8460160 | DOI:10.1093/jhps/hnab002

J Hip Preserv Surg. 2021 May 5;8(1):58-66. doi: 10.1093/jhps/hnab037. eCollection 2021 Jan.

ABSTRACT

Estimation of pelvic tilt on anteroposterior (AP) pelvis radiograph is often done by indirect methods based on the midline pelvic landmarks. The purpose of this cadaveric study is to describe a new radiographic landmark and reference measurements to estimate the coronal tilt of the pelvis, independent of the midline references. The new radiologic reference is called ‘rear drop’, and its anatomic location is described with the cadaveric pelvis AP radiographs in various pelvic inclination. The parameters derived from the new reference were used to assess the pelvic tilt, and the results were compared with the previously established method using ‘sacrococcygeal joint to symphysis distance’ (SCSD). The shape of the new figure is used to determine the position of the pelvis, and its relationship with the previously described acetabular retroversion indicators was statistically analyzed. The new reference figure corresponds to the posteroinferior edge of the horseshoe shape of the acetabular margin. The newly derived reference parameters, rear to tear distance and rear to tear angle, changes with pelvic tilt and are strongly correlated with SCSD. The shape of the rear drop changes with the changing pelvic tilt and correlates statistically with the previously described acetabular retroversion indicators. Rear drop and its derivative measurements can be used as a reliable and reproducible indicator to estimate the coronal pelvic tilt, free of midline reference points. This new reference will be a base for future clinical studies on pelvic tilt, rotation and their application in intraoperative hip fluoroscopy.

PMID:34567601 | PMC:PMC8460171 | DOI:10.1093/jhps/hnab037

R Soc Open Sci. 2021 Sep 22;8(9):210670. doi: 10.1098/rsos.210670. eCollection 2021 Sep.

ABSTRACT

Estimating the capabilities, or inputs of production, that drive and constrain the economic development of urban areas has remained a challenging goal. We posit that capabilities are instantiated in the complexity and sophistication of urban activities, the know-how of individual workers, and the city-wide collective know-how. We derive a model that indicates how the value of these three quantities can be inferred from the probability that an individual in a city is employed in a given urban activity. We illustrate how to estimate empirically these variables using data on employment across industries and metropolitan statistical areas in the USA. We then show how the functional form of the probability function derived from our theory is statistically superior when compared with competing alternative models, and that it explains well-known results in the urban scaling and economic complexity literature. Finally, we show how the quantities are associated with metrics of economic performance, suggesting our theory can provide testable implications for why some cities are more prosperous than others.

PMID:34567588 | PMC:PMC8456143 | DOI:10.1098/rsos.210670

R Soc Open Sci. 2021 Sep 22;8(9):211379. doi: 10.1098/rsos.211379. eCollection 2021 Sep.

ABSTRACT

The temporal evolution of second and subsequent waves of epidemics such as Covid-19 is investigated. Analytic expressions for the peak time and asymptotic behaviours, early doubling time, late half decay time, and a half-early peak law, characterizing the dynamical evolution of number of cases and fatalities, are derived, where the pandemic evolution exhibiting multiple waves is described by the semi-time SIR model. The asymmetry of the epidemic wave and its exponential tail are affected by the initial conditions, a feature that has no analogue in the all-time SIR model. Our analysis reveals that the immunity is very strongly increasing in several countries during the second Covid-19 wave. Wave-specific SIR parameters describing infection and recovery rates we find to behave in a similar fashion. Still, an apparently moderate change of their ratio can have significant consequences. As we show, the probability of an additional wave is however low in several countries due to the fraction of immune inhabitants at the end of the second wave, irrespective of the ongoing vaccination efforts. We compare with alternate approaches and data available at the time of submission. Most recent data serves to demonstrate the successful forecast and high accuracy of the SIR model in predicting the evolution of pandemic outbreaks as long as the assumption underlying our analysis, an unchanged situation of the distribution of variants of concern and the fatality fraction, do not change dramatically during a wave. With the rise of the α variant at the time of submission the second wave did not terminate in some countries, giving rise to a superposition of waves that is not treated by the present contribution.

PMID:34567593 | PMC:PMC8456141 | DOI:10.1098/rsos.211379