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Fulltext Anterior Displacement of Ulnar Nerve at the Elbow inChildren Based on Ultrasonography

Shamsul, H., Saw, A., John, G.

Malays Orthop J, 2007;1(1):29-33.
MyJurnal

This study involved evaluation of the elbows of 50 children between 4 to 14 years of age. Clinical examination for elbow flexion, extension, range of motion and carrying angle were performed, followed by ultrasonographic examination to determine position of the ulnar nerve in relation to the medial epicondyle upon elbow flexion and extension. Thirty-one elbows showed anterior displacement of the ulnar nerve, of which 14 were due to subluxation and 17 to dislocation. We found that anterior translation of ulnar nerve is present in the elbows up to 31% of children, especially those with increased range of elbow motion.
Early salvage hormonal therapy for biochemical failure improved survival in prostate cancer patients after neoadjuvant hormonal therapy plus radiation therapy--a secondary analysis of irish clinical oncology research group 97-01

Mydin AR, Dunne MT, Finn MA, Armstrong JG

Int J Radiat Oncol Biol Phys, 2013 Jan 1;85(1):101-8.
PMID: 22658512 DOI: 10.1016/j.ijrobp.2012.03.001

PURPOSE: To assess the survival benefit of early vs late salvage hormonal therapy (HT), we performed a secondary analysis on patients who developed recurrence from Irish Clinical Oncology Research Group 97-01, a randomized trial comparing 4 vs 8 months neoadjuvant HT plus radiation therapy (RT) in intermediate- and high-risk prostate adenocarcinoma.
METHODS AND MATERIALS: A total of 102 patients from the trial who recurred were analyzed at a median follow-up of 8.5 years. The patients were divided into 3 groups based on the timing of salvage HT: 57 patients had prostate-specific antigen (PSA)≤10 ng/mL and absent distant metastases (group 1, early), 21 patients had PSA>10 ng/mL and absent distant metastases (group 2, late), and 24 patients had distant metastases (group 3, late). The endpoint analyzed was overall survival (OS) calculated from 2 different time points: date of enrolment in the trial (OS1) and date of initiation of salvage HT (OS2). Survival was estimated using Kaplan-Meier curves and a Cox regression model.
RESULTS: The OS1 differed significantly between groups (P
Fulltext Examining Knowledge Diffusion in the Circular Economy Domain: a Main Path Analysis

Rejeb A, Rejeb K, Zailani S, Kayikci Y, Keogh JG

Circ Econ Sustain, 2023;3(1):125-166.
PMID: 35818534 DOI: 10.1007/s43615-022-00189-3

The circular economy (CE) field has recently attracted significant interest from academics and practitioners. CE represents a departure from the linear economy, which is characterised by unsustainable resource production and consumption. The growing number of publications necessitates a comprehensive analysis of this field. This is the first systematic examination of the knowledge base and knowledge diffusion pathways in the CE domain. We analyse a Web of Science dataset containing 5431 articles published between 1970 and 2020. To create a comprehensive review of the CE domain, we conducted a keyword co-occurrence network analysis. We examined four distinct types of main paths using the main path analysis (MPA) technique: forward, backward, global, and key-route. According to the analyses, CE research focuses on six primary research themes: CE and sustainability, bioeconomy, CE practices, lifecycle assessment and industrial symbiosis, construction activities, and waste management. In addition, the MPA demonstrates that the CE literature has recently focused on Industry 4.0 technologies and their contribution to CE. This is the first attempt to depict the genealogy of CE research so that scholars can comprehend the domain's evolutionary structure, identify hot topics, and capture the history, development status, and potential future directions of CE research.
Fulltext Biliary cystadenoma - computed tomography findings

Ariff A, Hassan H, John G

Malays J Med Sci, 2002 Jan;9(1):49-51.
PMID: 22969318

Biliary cystadenoma is a rare neoplasm of the biliary ductal system. Surgical management yields an excellent result. We present a case of recurrent biliary cystadenoma in the left lobe of the liver. The cyst was successfully treated with hepatic segmentectomy. The lobulated smoothly marginated septated cystic lesion noted on computed tomography (CT) were highlighted and the other imaging studies, differential diagnosis and management were reviewed.
Lumbosacral osteosarcoma with dural spread, skip lesions and intravascular extension: A case report

Noor Khairiah AK, Mohamad Nazrulhisham MN, John G

Med J Malaysia, 2018 04;73(2):116-118.
PMID: 29703878 MyJurnal

Primary osteosarcoma of the spine is indeed rare and only several sporadic cases have been reported. It tends to occur in a slightly older age group than those with appendicular skeleton tumours. We present here an unusual case of aggressive lumbosacral osteosarcoma in a young teenager complicated by extensive dural spread, skip lesions and intravascular extension. Although a histopathological examination is mandatory to establish the diagnosis, this case emphasises the need of imaging to ascertain the full extent of disease spread especially in deciding the type of treatment to be instituted and to evaluate the response to the treatment.
Variability and repeatability of quantitative, Fourier-domain optical coherence tomography Doppler blood flow in young and elderly healthy subjects

Tayyari F, Yusof F, Vymyslicky M, Tan O, Huang D, Flanagan JG, et al.

Invest Ophthalmol Vis Sci, 2014 Dec;55(12):7716-25.
PMID: 25335983 DOI: 10.1167/iovs.14-14430

The purpose of this study was to determine the within-session variability and between-session repeatability of spectral Fourier-domain optical coherence tomography (Doppler FD-OCT) Doppler retinal blood flow measurements in young and elderly subjects.
Microsatellite variation among divergent populations of stalk-eyed flies, genus Cyrtodiopsis

Wright TF, Johns PM, Walters JR, Lerner AP, Swallow JG, Wilkinson GS

Genet. Res., 2004 Aug;84(1):27-40.
PMID: 15663256

Microsatellite primers are often developed in one species and used to assess neutral variability in related species. Such analyses may be confounded by ascertainment bias (i.e. a decline in amplification success and allelic variability with increasing genetic distance from the source of the microsatellites). In addition, other factors, such as the size of the microsatellite, whether it consists of perfect or interrupted tandem repeats, and whether it is autosomal or X-linked, can affect variation. To test the relative importance of these factors on microsatellite variation, we examine patterns of amplification and allelic diversity in 52 microsatellite loci amplified from five individuals in each of six populations of Cyrtodiopsis stalk-eyed flies that range from 2.2 % to 11.2% mitochondrial DNA sequence divergence from the population used for microsatellite development. We find that amplification success and most measures of allelic diversity declined with genetic distance from the source population, in some cases an order of magnitude faster than in birds or mammals. The median and range of the repeat array length did not decline with genetic distance. In addition, for loci on the X chromosome, we find evidence of lower observed heterozygosity compared with loci on autosomes. The differences in variability between X-linked and autosomal loci are not adequately explained by differences in effective population sizes of the chromosomes. We suggest, instead, that periodic selection events associated with X-chromosome meiotic drive, which is present in many of these populations, reduces X-linked variation.
Platelet-Rich Plasma Injection for the Treatment of Hamstring Injuries: A Systematic Review and Meta-analysis With Best-Worst Case Analysis

Seow D, Shimozono Y, Tengku Yusof TNB, Yasui Y, Massey A, Kennedy JG

Am J Sports Med, 2021 02;49(2):529-537.
PMID: 32427520 DOI: 10.1177/0363546520916729

BACKGROUND: Hamstring injuries are common and account for considerable time lost to play in athletes. Platelet-rich plasma has potential as a means to accelerate healing of these injuries.
PURPOSE: (1) To present the evidence of platelet-rich plasma injection in the treatment of hamstring injuries, (2) evaluate the "best-case scenario" in dichotomous outcomes, and (3) evaluate the "worst-case scenario" in dichotomous outcomes.
STUDY DESIGN: Systematic review and meta-analysis.
METHODS: Two authors systematically reviewed the PubMed, Embase, and Cochrane Library databases according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, with any discrepancies resolved by mutual consensus. The level of evidence was assessed per the criteria of the Oxford Centre for Evidence-Based Medicine and the quality of evidence by the Coleman Methodology Score. Meta-analysis by fixed effects models was used if heterogeneity was low (I2 < 25%) and random effects models if heterogeneity was moderate to high (I2≥ 25%). P values
Treatment Options for Turf Toe: A Systematic Review

Seow D, Tengku Yusof TNB, Yasui Y, Shimozono Y, Kennedy JG

J Foot Ankle Surg, 2019 12 29;59(1):112-116.
PMID: 31882133 DOI: 10.1053/j.jfas.2018.12.041

Turf toe is hyperextension injury of the plantar plate at the first metatarsophalangeal joint. Etiologies have often included sports/activities with excessive forefoot axial loading and/or violent pivotal movements. The purpose of the systematic review was to systematically review and present an overview for the current evidence-based treatment options of turf toe. Both authors systematically reviewed the PubMed and EMBASE databases from inception to April 2016 based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The level of evidence and quality of evidence were assessed by using the Level of Evidence for Primary Research Question of the Journal of Bone and Joint Surgery, and the quality of evidence was assessed with use of the Newcastle-Ottawa scale. Data were collected and categorized into: case reports and case series. Eight studies (16 turf toes) met the aforementioned criteria and were included. Five case reports and 3 case series reported various treatment options for turf toe. Specifically, 3 studies reported solely conservative treatment (n = 5), 1 study reported solely surgical treatment (n = 1), and 4 studies involved patients in conservative and/or surgical treatments (n = 10). All studies were of level of clinical evidence 4 and quality of clinical evidence score 2 (poor quality). Conservative treatment included closed reduction and immobilization, and surgical treatment included plantar plate tenodesis. Restricted dorsiflexion was the most common complication reported. Turf toe is an underreported injury with no evidence-based treatment guideline to date. Future studies of higher level and quality of evidence with a specific classification system (Jahss or Anderson) consistently reported are warranted for the development of an optimal guideline to determine the most appropriate treatment for each specific severity in injury.
Fulltext Relationship between retinal blood flow and arterial oxygen

Cheng RW, Yusof F, Tsui E, Jong M, Duffin J, Flanagan JG, et al.

J Physiol, 2016 Feb 01;594(3):625-40.
PMID: 26607393 DOI: 10.1113/JP271182

KEY POINTS: Vascular reactivity, the response of the vessels to a vasoactive stimulus such as hypoxia and hyperoxia, can be used to assess the vascular range of adjustment in which the vessels are able to compensate for changes in PO2. Previous studies in the retina have not accurately quantified retinal vascular responses and precisely targeted multiple PaO2 stimuli at the same time as controlling the level of carbon dioxide, thus precluding them from modelling the relationship between retinal blood flow and oxygen. The present study modelled the relationship between retinal blood flow and PaO2, showing them to be a combined linear and hyperbolic function. This model demonstrates that the resting tonus of the vessels is at the mid-point and that they have great vascular range of adjustment, compensating for decreases in oxygen above a PETCO2 of 32-37 mmHg but being limited below this threshold. Retinal blood flow (RBF) increases in response to a reduction in oxygen (hypoxia) but decreases in response to increased oxygen (hyperoxia). However, the relationship between blood flow and the arterial partial pressure of oxygen has not been quantified and modelled in the retina, particularly in the vascular reserve and resting tonus of the vessels. The present study aimed to determine the limitations of the retinal vasculature by modelling the relationship between RBF and oxygen. Retinal vascular responses were measured in 13 subjects for eight different blood gas conditions, with the end-tidal partial pressure of oxygen (PETCO2) ranging from 40-500 mmHg. Retinal vascular response measurements were repeated twice; using the Canon laser blood flowmeter (Canon Inc., Tokyo, Japan) during the first visit and using Doppler spectral domain optical coherence tomography during the second visit. We determined that the relationship between RBF and PaO2 can be modelled as a combination of hyperbolic and linear functions. We concluded that RBF compensated for decreases in arterial oxygen content for all stages of hypoxia used in the present study but can no longer compensate below a PETCO2 of 32-37 mmHg. These vessels have a great vascular range of adjustment, increasing diameter (8.5% arteriolar and 21% total venous area) with hypoxia (40 mmHg P ETC O2; P < 0.001) and decreasing diameter (6.9% arteriolar and 23% total venous area) with hyperoxia (500 mmHg PETCO2; P < 0.001) to the same extent. This indicates that the resting tonus is near the mid-point of the adjustment ranges at resting PaO2 where sensitivity is maximum.
Fulltext Different ommochrome pigment mixtures enable sexually dimorphic Batesian mimicry in disjunct populations of the common palmfly butterfly, Elymnias hypermnestra

Panettieri S, Gjinaj E, John G, Lohman DJ

PLoS One, 2018;13(9):e0202465.
PMID: 30208047 DOI: 10.1371/journal.pone.0202465

With varied, brightly patterned wings, butterflies have been the focus of much work on the evolution and development of phenotypic novelty. However, the chemical structures of wing pigments from few butterfly species have been identified. We characterized the orange wing pigments of female Elymnias hypermnestra butterflies (Lepidoptera: Nymphalidae: Satyrinae) from two Southeast Asian populations. This species is a sexually dimorphic Batesian mimic of several model species. Females are polymorphic: in some populations, females are dark, resemble conspecific males, and mimic Euploea spp. In other populations, females differ from males and mimic orange Danaus spp. Using LC-MS/MS, we identified nine ommochrome pigments: six from a population in Chiang Mai, Thailand, and five compounds from a population in Bali, Indonesia. Two ommochromes were found in both populations, and only two of the nine compounds have been previously reported. The sexually dimorphic Thai and Balinese populations are separated spatially by monomorphic populations in peninsular Malaysia, Singapore, and Sumatra, suggesting independent evolution of mimetic female wing pigments in these disjunct populations. These results indicate that other butterfly wing pigments remain to be discovered.
Fulltext The Lancet Commission on diagnostics: transforming access to diagnostics

Fleming KA, Horton S, Wilson ML, Atun R, DeStigter K, Flanigan J, et al.

Lancet, 2021 Nov 27;398(10315):1997-2050.
PMID: 34626542 DOI: 10.1016/S0140-6736(21)00673-5
Fulltext Differentiation of Prior SARS-CoV-2 Infection and Postacute Sequelae by Standard Clinical Laboratory Measurements in the RECOVER Cohort

Erlandson KM, Geng LN, Selvaggi CA, Thaweethai T, Chen P, Erdmann NB, et al.

Ann Intern Med, 2024 Sep;177(9):1209-1221.
PMID: 39133923 DOI: 10.7326/M24-0737

BACKGROUND: There are currently no validated clinical biomarkers of postacute sequelae of SARS-CoV-2 infection (PASC).
OBJECTIVE: To investigate clinical laboratory markers of SARS-CoV-2 and PASC.
DESIGN: Propensity score-weighted linear regression models were fitted to evaluate differences in mean laboratory measures by prior infection and PASC index (≥12 vs. 0). (ClinicalTrials.gov: NCT05172024).
SETTING: 83 enrolling sites.
PARTICIPANTS: RECOVER-Adult cohort participants with or without SARS-CoV-2 infection with a study visit and laboratory measures 6 months after the index date (or at enrollment if >6 months after the index date). Participants were excluded if the 6-month visit occurred within 30 days of reinfection.
MEASUREMENTS: Participants completed questionnaires and standard clinical laboratory tests.
RESULTS: Among 10 094 participants, 8746 had prior SARS-CoV-2 infection, 1348 were uninfected, 1880 had a PASC index of 12 or higher, and 3351 had a PASC index of zero. After propensity score adjustment, participants with prior infection had a lower mean platelet count (265.9 × 109 cells/L [95% CI, 264.5 to 267.4 × 109 cells/L]) than participants without known prior infection (275.2 × 109 cells/L [CI, 268.5 to 282.0 × 109 cells/L]), as well as higher mean hemoglobin A1c (HbA1c) level (5.58% [CI, 5.56% to 5.60%] vs. 5.46% [CI, 5.40% to 5.51%]) and urinary albumin-creatinine ratio (81.9 mg/g [CI, 67.5 to 96.2 mg/g] vs. 43.0 mg/g [CI, 25.4 to 60.6 mg/g]), although differences were of modest clinical significance. The difference in HbA1c levels was attenuated after participants with preexisting diabetes were excluded. Among participants with prior infection, no meaningful differences in mean laboratory values were found between those with a PASC index of 12 or higher and those with a PASC index of zero.
LIMITATION: Whether differences in laboratory markers represent consequences of or risk factors for SARS-CoV-2 infection could not be determined.
CONCLUSION: Overall, no evidence was found that any of the 25 routine clinical laboratory values assessed in this study could serve as a clinically useful biomarker of PASC.
PRIMARY FUNDING SOURCE: National Institutes of Health.
Fulltext Corrigendum re "Genetic Variants Related to Longer Telomere Length are Associated with Increased Risk of Renal Cell Carcinoma" [Eur Urol 2017;72:747-54]

Machiela MJ, Hofmann JN, Carreras-Torres R, Brown KM, Johansson M, Wang Z, et al.

Eur Urol, 2018 Sep;74(3):e85-e86.
PMID: 29853305 DOI: 10.1016/j.eururo.2018.05.017
Fulltext Genetic Variants Related to Longer Telomere Length are Associated with Increased Risk of Renal Cell Carcinoma

Machiela MJ, Hofmann JN, Carreras-Torres R, Brown KM, Johansson M, Wang Z, et al.

Eur Urol, 2017 Nov;72(5):747-754.
PMID: 28797570 DOI: 10.1016/j.eururo.2017.07.015

BACKGROUND: Relative telomere length in peripheral blood leukocytes has been evaluated as a potential biomarker for renal cell carcinoma (RCC) risk in several studies, with conflicting findings.
OBJECTIVE: We performed an analysis of genetic variants associated with leukocyte telomere length to assess the relationship between telomere length and RCC risk using Mendelian randomization, an approach unaffected by biases from temporal variability and reverse causation that might have affected earlier investigations.
DESIGN, SETTING, AND PARTICIPANTS: Genotypes from nine telomere length-associated variants for 10 784 cases and 20 406 cancer-free controls from six genome-wide association studies (GWAS) of RCC were aggregated into a weighted genetic risk score (GRS) predictive of leukocyte telomere length.
OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Odds ratios (ORs) relating the GRS and RCC risk were computed in individual GWAS datasets and combined by meta-analysis.
RESULTS AND LIMITATIONS: Longer genetically inferred telomere length was associated with an increased risk of RCC (OR=2.07 per predicted kilobase increase, 95% confidence interval [CI]:=1.70-2.53, p<0.0001). As a sensitivity analysis, we excluded two telomere length variants in linkage disequilibrium (R2>0.5) with GWAS-identified RCC risk variants (rs10936599 and rs9420907) from the telomere length GRS; despite this exclusion, a statistically significant association between the GRS and RCC risk persisted (OR=1.73, 95% CI=1.36-2.21, p<0.0001). Exploratory analyses for individual histologic subtypes suggested comparable associations with the telomere length GRS for clear cell (N=5573, OR=1.93, 95% CI=1.50-2.49, p<0.0001), papillary (N=573, OR=1.96, 95% CI=1.01-3.81, p=0.046), and chromophobe RCC (N=203, OR=2.37, 95% CI=0.78-7.17, p=0.13).
CONCLUSIONS: Our investigation adds to the growing body of evidence indicating some aspect of longer telomere length is important for RCC risk.
PATIENT SUMMARY: Telomeres are segments of DNA at chromosome ends that maintain chromosomal stability. Our study investigated the relationship between genetic variants associated with telomere length and renal cell carcinoma risk. We found evidence suggesting individuals with inherited predisposition to longer telomere length are at increased risk of developing renal cell carcinoma.
Fulltext Author Correction: Dense sampling of bird diversity increases power of comparative genomics

Feng S, Stiller J, Deng Y, Armstrong J, Fang Q, Reeve AH, et al.

Nature, 2021 Apr;592(7856):E24.
PMID: 33833441 DOI: 10.1038/s41586-021-03473-8
Fulltext Dense sampling of bird diversity increases power of comparative genomics

Feng S, Stiller J, Deng Y, Armstrong J, Fang Q, Reeve AH, et al.

Nature, 2020 11;587(7833):252-257.
PMID: 33177665 DOI: 10.1038/s41586-020-2873-9

Whole-genome sequencing projects are increasingly populating the tree of life and characterizing biodiversity1-4. Sparse taxon sampling has previously been proposed to confound phylogenetic inference5, and captures only a fraction of the genomic diversity. Here we report a substantial step towards the dense representation of avian phylogenetic and molecular diversity, by analysing 363 genomes from 92.4% of bird families-including 267 newly sequenced genomes produced for phase II of the Bird 10,000 Genomes (B10K) Project. We use this comparative genome dataset in combination with a pipeline that leverages a reference-free whole-genome alignment to identify orthologous regions in greater numbers than has previously been possible and to recognize genomic novelties in particular bird lineages. The densely sampled alignment provides a single-base-pair map of selection, has more than doubled the fraction of bases that are confidently predicted to be under conservation and reveals extensive patterns of weak selection in predominantly non-coding DNA. Our results demonstrate that increasing the diversity of genomes used in comparative studies can reveal more shared and lineage-specific variation, and improve the investigation of genomic characteristics. We anticipate that this genomic resource will offer new perspectives on evolutionary processes in cross-species comparative analyses and assist in efforts to conserve species.
Fulltext Phylogenomics and the rise of the angiosperms

Zuntini AR, Carruthers T, Maurin O, Bailey PC, Leempoel K, Brewer GE, et al.

Nature, 2024 May;629(8013):843-850.
PMID: 38658746 DOI: 10.1038/s41586-024-07324-0

Angiosperms are the cornerstone of most terrestrial ecosystems and human livelihoods1,2. A robust understanding of angiosperm evolution is required to explain their rise to ecological dominance. So far, the angiosperm tree of life has been determined primarily by means of analyses of the plastid genome3,4. Many studies have drawn on this foundational work, such as classification and first insights into angiosperm diversification since their Mesozoic origins5-7. However, the limited and biased sampling of both taxa and genomes undermines confidence in the tree and its implications. Here, we build the tree of life for almost 8,000 (about 60%) angiosperm genera using a standardized set of 353 nuclear genes8. This 15-fold increase in genus-level sampling relative to comparable nuclear studies9 provides a critical test of earlier results and brings notable change to key groups, especially in rosids, while substantiating many previously predicted relationships. Scaling this tree to time using 200 fossils, we discovered that early angiosperm evolution was characterized by high gene tree conflict and explosive diversification, giving rise to more than 80% of extant angiosperm orders. Steady diversification ensued through the remaining Mesozoic Era until rates resurged in the Cenozoic Era, concurrent with decreasing global temperatures and tightly linked with gene tree conflict. Taken together, our extensive sampling combined with advanced phylogenomic methods shows the deep history and full complexity in the evolution of a megadiverse clade.

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