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Although mucormycosis is an important cause of morbidity and mortality in children with cancer, our understanding of the typical characteristics of these infections is incomplete. We reviewed all cases of mucormycosis diagnosed at a single pediatric cancer center over 5 decades to identify the clinical features of mucormycosis in pediatric oncology patients and to identify risk factors for mortality. There were 44 cases of mucormycosis diagnosed between 1970-2019. Most patients (89%) had hematological malignancies and a history of prolonged and severe neutropenia (91%). In this series, hyperglycemia and exposure to corticosteroids were common. Pulmonary (36%) and disseminated infections (32%) were most common; rhino-orbital-cerebral infections were relatively infrequent (11%). Rhizopus spp. was the most common etiological agent (40%) followed by Mucor spp. (31%), and Cunninghamella spp. (19%). Overall mortality was 44% and 51% and attributable mortality was 39% and 41% at the end of antifungal therapy and end of follow up, respectively. Attributable mortality fell to 18% in 2010-2019, from 58-60% in previous decades; adjunctive surgery was associated with decreased mortality. Mortality remains unacceptably high despite aggressive antifungal therapy and adjunctive surgery, suggesting novel therapeutic strategies are needed., Competing Interests: I have read the journal’s policy and the authors of this manuscript have the following competing interests: R.H. reports receiving consultant fees from MiraVista and Abbott Laboratories and G.M. is the recipient of research funding from Astellas Pharma Inc. and SymBio Pharmaceuticals. No other authors have competing interests., (Copyright: © 2024 Marón et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

The iron overload disorder hemochromatosis is primarily caused by the homozygous HFE p.C282Y variant, but the scale of excess related musculoskeletal morbidity is uncertain. We estimated hemochromatosis-genotype associations with clinically diagnosed musculoskeletal outcomes and joint replacement surgeries in the UK Biobank community cohort. A total of 451,143 European ancestry participants (40 to 70 years at baseline) were followed in hospital records (mean 11.5-years). Cox proportional hazards models estimated HFE p.C282Y and p.H63D associations with incident outcomes. Male p.C282Y homozygotes ( n  = 1294) had increased incidence of osteoarthritis ( n  = 52, hazard ratio [HR]: 2.12 [95% confidence interval, CI: 1.61 to 2.80]; p  = 8.8 × 10 -8 ), hip replacement ( n  = 88, HR: 1.84 [95% CI: 1.49 to 2.27]; p  = 1.6 × 10 -8 ), knee replacement ( n  = 61, HR: 1.54 [95% CI: 1.20 to 1.98]; p  = 8.4 × 10 -4 ), and ankle and shoulder replacement, compared to males with no HFE mutations. Cumulative incidence analysis, using Kaplan-Meier lifetable probabilities demonstrated 10.4% of male homozygotes were projected to develop osteoarthritis and 15.5% to have hip replacements by age 75, versus 5.0% and 8.7% respectively without mutations. Male p.C282Y homozygotes also had increased incidence of femoral fractures ( n  = 15, HR: 1.72 [95% CI: 1.03 to 2.87]; p  = 0.04) and osteoporosis ( n  = 21, HR: 1.71 [95% CI: 1.11 to 2.64]; p  = 0.02), although the latter association was limited to those with liver fibrosis/cirrhosis diagnoses. Female p.C282Y homozygotes had increased incidence of osteoarthritis only ( n  = 57, HR: 1.46, [95% CI: 1.12 to 1.89]; p  = 0.01). Male p.C282Y/p.H63D compound heterozygotes experienced a modest increased risk of hip replacements ( n  = 234, HR: 1.17 [95% CI: 1.02 to 1.33], p  = 0.02), but this did not pass multiple testing corrections. In this large community cohort, the p.C282Y homozygote genotype was associated with substantial excess musculoskeletal morbidity in males. Wider HFE genotype testing may be justified, including in orthopedic clinics serving higher HFE variant prevalence populations. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC. on behalf of American Society for Bone and Mineral Research., Competing Interests: The authors declare no conflicts of interest., (© 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC. on behalf of American Society for Bone and Mineral Research.)

Background: It remains unclear whether non-animal-derived dietary protein sources (and therefore vegan diets) can support resistance training-induced skeletal muscle remodeling to the same extent as animal-derived protein sources., Methods: In Phase 1, 16 healthy young adults (m = 8, f = 8; age: 23 ± 1 y; BMI: 23 ± 1 kg/m 2 ) completed a 3-d dietary intervention (high protein, 1.8 g·kg bm -1 ·d -1 ) where protein was derived from omnivorous (OMNI1; n = 8) or exclusively non-animal (VEG1; n = 8) sources, alongside daily unilateral leg resistance exercise. Resting and exercised daily myofibrillar protein synthesis (MyoPS) rates were assessed using deuterium oxide. In Phase 2, 22 healthy young adults (m = 11, f = 11; age: 24 ± 1 y; BMI: 23 ± 0 kg/m 2 ) completed a 10 wk, high-volume (5 d/wk), progressive resistance exercise program while consuming an omnivorous (OMNI2; n = 12) or non-animal-derived (VEG2; n = 10) high-protein diet (∼2 g·kg bm -1 ·d -1 ). Muscle fiber cross-sectional area (CSA), whole-body lean mass (via DXA), thigh muscle volume (via MRI), muscle strength, and muscle function were determined pre, after 2 and 5 wk, and postintervention., Objectives: To investigate whether a high-protein, mycoprotein-rich, non-animal-derived diet can support resistance training-induced skeletal muscle remodeling to the same extent as an isonitrogenous omnivorous diet., Results: Daily MyoPS rates were ∼12% higher in the exercised than in the rested leg (2.46 ± 0.27%·d -1 compared with 2.20 ± 0.33%·d -1 and 2.62 ± 0.56%·d - 1 compared with 2.36 ± 0.53%·d -1 in OMNI1 and VEG1, respectively; P < 0.001) and not different between groups (P > 0.05). Resistance training increased lean mass in both groups by a similar magnitude (OMNI2 2.6 ± 1.1 kg, VEG2 3.1 ± 2.5 kg; P > 0.05). Likewise, training comparably increased thigh muscle volume (OMNI2 8.3 ± 3.6%, VEG2 8.3 ± 4.1%; P > 0.05), and muscle fiber CSA (OMNI2 33 ± 24%, VEG2 32 ± 48%; P > 0.05). Both groups increased strength (1 repetition maximum) of multiple muscle groups, to comparable degrees., Conclusions: Omnivorous and vegan diets can support comparable rested and exercised daily MyoPS rates in healthy young adults consuming a high-protein diet. This translates to similar skeletal muscle adaptive responses during prolonged high-volume resistance training, irrespective of dietary protein provenance. This trial was registered at clinicaltrials.gov as NCT03572127., (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)

Objective: Poor vascular health is associated with reduced bone strength and increased risk of fragility fracture. However, direct measurement of intraosseous vascular health is difficult due to the density and mineral content of bone. We investigated the feasibility of using a commercially available continuous wave near infrared spectroscopy (NIRS) system for the investigation of vascular haemodynamics in human bone in vivo . Approach: An arterial occlusion (AO) protocol was developed for obtaining haemodynamic measurements of the proximal tibia and lateral calf, including assessment of the protocol's intra operator reproducibility. For 36 participants, intraosseous haemodynamics derived by NIRS were compared to alternative tests of bone health based on dual x-ray absorptiometry (DXA) testing and MRI. Main Results: Near infrared spectroscopy markers of haemodynamics of the proximal tibia demonstrated acceptable reproducibility, comparable with reproducibility assessments of alternative modalities measuring intraosseous haemodynamics, and the use of NIRS for measuring muscle. Novel associations have been demonstrated between haemodynamic markers of bone measured with NIRS and body composition and bone mineral density (BMD) measurements obtained with both DXA and MRI. Significance: Near infrared spectroscopy provides inexpensive, non-invasive, safe, and real time data on changes in oxygenated and deoxygenated haemoglobin concentration in bone at the proximal tibia. This study has demonstrated the potential for NIRS to contribute to research investigating the pathophysiological role of vascular dysfunction within bone tissue, but also the limitations and need for further development of NIRS technology., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Meertens, Knapp, Strain, Casanova, Ball, Fulford and Thorn.)

The MCM2-7 helicase is a heterohexameric complex with essential roles as part of both the pre-replication and pre-initiation complexes in the early stages of DNA replication. Meier-Gorlin syndrome, a rare primordial dwarfism, is strongly associated with disruption to the pre-replication complex, including a single case described with variants in MCM5. Conversely, a biallelic pathogenic variant in MCM4 underlies immune deficiency with growth retardation, features also seen in individuals with pathogenic variants in other pre-initiation complex encoding genes such as GINS1, MCM10, and POLE. Through exome and chromium genome sequencing, supported by functional studies, we identify biallelic pathogenic variants in MCM7 and a strong candidate biallelic pathogenic variant in MCM3. We confirm variants in MCM7 are deleterious and through interfering with MCM complex formation, impact efficiency of S phase progression. The associated phenotypes are striking; one patient has typical Meier-Gorlin syndrome, whereas the second case has a multi-system disorder with neonatal progeroid appearance, lipodystrophy and adrenal insufficiency. We provide further insight into the developmental complexity of disrupted MCM function, highlighted by two patients with a similar variant profile in MCM7 but disparate clinical features. Our results build on other genetic findings linked to disruption of the pre-replication and pre-initiation complexes, and the replisome, and expand the complex clinical genetics landscape emerging due to disruption of DNA replication., (© 2021. The Author(s), under exclusive licence to European Society of Human Genetics.)

Disruption of the initiation of DNA replication is significantly associated with Meier-Gorlin syndrome (MGORS), an autosomal recessive condition of reduced growth, microtia and patellar a/hypoplasia. Biallelic mutations in CDC45, a member of the pre-initiation complex in DNA replication, cause a spectrum of phenotypes ranging from MGORS with craniosynostosis, through to isolated short stature and craniosynostosis. Here we report two affected sibs with MGORS and craniosynostosis, with biallelic variants in CDC45 identified by 10X Chromium whole genome sequencing. One variant is a frameshift mutation, predicted to be pathogenic, and is inherited in trans with a synonymous variant in a non-canonical exon (exon 7) of CDC45. An in vitro splicing assay showed that while the canonical CDC45 exon 6-exon 8 transcript (with skipping of exon 7; numbering as per NM001178010.2) remained as the predominant transcript, the variant allele induced the use of novel splice acceptor sites in intron 6, all of which produced transcripts harbouring premature stop codons. This perturbation of canonical splicing provides evidence that this synonymous variant is indeed a deleterious alteration in this family. This report adds to the initial patient cohort in which several synonymous variants were also described, further highlighting the contribution of this variant type in CDC45. It also reiterates the true potential pathogenicity of synonymous variants, which is a mutation type that is commonly ignored in variant prioritization strategies., (Copyright © 2021 Elsevier Masson SAS. All rights reserved.)

ABL1 is a proto-oncogene encoding a nonreceptor tyrosine kinase, best known in the somatic BCR-ABL fusion gene associated with chronic myeloid leukaemia. Recently, germline missense variants in ABL1 have been found to cause an autosomal dominant developmental syndrome with congenital heart disease, skeletal malformations and characteristic facies. Here, we describe a series of six new unrelated individuals with heterozygous missense variants in ABL1 (including four novel variants) identified via whole exome sequencing. All the affected individuals in this series recapitulate the phenotype of the ABL1 developmental syndrome and additionally we affirm that hearing impairment is a common feature of the condition. Four of the variants cluster in the myristoyl-binding pocket of ABL1, a region critical for auto-inhibitory regulation of the kinase domain. Bio-informatic analysis of transcript-wide conservation and germline/somatic variation reveals that this pocket region is subject to high missense constraint and evolutionary conservation. Functional work to investigate ABL1 kinase activity in vitro by transient transfection of HEK293T cells with variant ABL1 plasmid constructs revealed increased phosphorylation of ABL1-specific substrates compared to wild-type. The increased tyrosine kinase activity was suppressed by imatinib treatment. This case series of six new patients with germline heterozygous ABL1 missense variants further delineates the phenotypic spectrum of this condition and recognises microcephaly as a common finding. Our analysis supports an ABL1 gain-of-function mechanism due to loss of auto-inhibition, and demonstrates the potential for pharmacological inhibition using imatinib.

Fractures of the wrist are common in Emergency Departments, where some patients are treated with a procedure called Manipulation under Anaesthesia. In some cases, this procedure is unsuccessful and patients need to revisit the hospital where they undergo surgery to treat the fracture. This work describes a geometric semi-automatic image analysis algorithm to analyse and compare the x-rays of healthy controls and patients with dorsally displaced wrist fractures (Colles' fractures) who were treated with Manipulation under Anaesthesia. A series of 161 posterior-anterior radiographs from healthy controls and patients with Colles' fractures were acquired and analysed. The patients' group was further subdivided according to the outcome of the procedure (successful/unsuccessful) and pre- or post-intervention creating five groups in total (healthy, pre-successful, pre-unsuccessful, post-successful, post-unsuccessful). The semi-automatic analysis consisted of manual location of three landmarks (finger, lunate and radial styloid) and automatic processing to generate 32 geometric and texture measurements, which may be related to conditions such as osteoporosis and swelling of the wrist. Statistical differences were found between patients and controls, as well as between pre- and post-intervention, but not between the procedures. The most distinct measurements were those of texture. Although the study includes a relatively low number of cases and measurements, the statistical differences are encouraging., Competing Interests: The authors have declared that no competing interests exist.

Variants in SLC35C1 underlie leucocyte adhesion deficiency (LADII) or congenital disorder of glycosylation type 2c (CDGIIc), an autosomal recessive disorder of fucosylation. This immunodeficiency syndrome is generally characterized by severe recurrent infections, Bombay blood group, reduced growth and intellectual disability (ID). Features are all caused by an inability to generate key fucosylated molecules due to a defective transport of GDP-fucose into the Golgi. Here we report the use of exome sequencing to identify biallelic variants in SLC35C1 (c.501&#95;503delCTT, p.(Phe168del) and c.891T > G, p.(Asn297Lys)) in an individual with short stature and ID. Retrospective clinical examination based on the genetic findings revealed increased otitis media as the only immunological feature present in this child. Biochemical analysis of patient serum identified a clear but mild decrease in protein fucosylation. Modelling all described missense mutations on a SLC35C1 protein model showed pathogenic substitutions localise to close to the dimer interface, providing insight into the possible pathophysiology of non-synonymous causative variants identified in patients. Our evidence confirms this is the second family presenting with only a subset of features and broadens the clinical presentation of this syndrome. Of note, both families segregated a common allele (p.Phe168del), suggesting there could be an associated genotype-phenotype relationship for specific variants. Based on two out of 14 reported families not presenting with the characteristic features of SLC35C1-CDG, we suggest there is clinical utility in considering this gene in patients with short stature and ID.

The purpose of this study was to evaluate the pharmacokinetics of ritonavir-boosted fosamprenavir during pregnancy and postpartum. Amprenavir (the active moiety of fosamprenavir) and ritonavir intensive pharmacokinetic evaluations were performed at steady state during the second and third trimesters of pregnancy and postpartum. Plasma concentrations of amprenavir and ritonavir were measured using high-performance liquid chromatography. The target amprenavir area under the concentration-versus-time curve (AUC) was higher than the 10th percentile (27.7 μg · h/ml) of the median area under the curve for ritonavir-boosted fosamprenavir in adults receiving twice-daily fosamprenavir-ritonavir at 700 mg/100 mg. Twenty-nine women were included in the analysis. The amprenavir AUC from time zero to 12 h (AUC 0-12 ) was lower (geometric mean ratio [GMR], 0.60 [confidence interval {CI}, 0.49 to 0.72] [ P  < 0.001]) while its apparent oral clearance was higher (GMR, 1.68 [CI, 1.38 to 2.03] [ P  < 0.001]) in the third trimester than postpartum. Similarly, the ritonavir AUC 0-12 was lower in the second (GMR, 0.51 [CI, 0.28 to 0.91] [ P  = 0.09]) and third (GMR, 0.72 [CI, 0.55 to 0.95] [ P  = 0.005]) trimesters than postpartum, while its apparent oral clearance was higher in the second (GMR, 1.98 [CI, 1.10 to 3.56] [ P  = 0.06]) and third (GMR, 1.38 [CI, 1.05 to 1.82] [ P  = 0.009]) trimesters than postpartum. The amprenavir area under the curve exceeded the target for 6/8 (75%) women in the 2nd trimester, 18/28 (64%) in the 3rd trimester, and 19/22 (86.4%) postpartum, and the trough concentrations ( C min ) of amprenavir were 4- to 16-fold above the mean amprenavir-protein-adjusted 50% inhibitory concentration (IC 50 ) of 0.146 μg/ml. Although amprenavir plasma concentrations in women receiving ritonavir-boosted fosamprenavir were lower during pregnancy than postpartum, the reduced amprenavir concentrations were still above the exposures needed for viral suppression., (Copyright © 2020 American Society for Microbiology.)

Material: Linked-read whole genome sequencing (WGS) presents a new opportunity for cost-efficient singleton sequencing in place of traditional trio-based designs while generating informative-phased variants, effective for recessive disorders when parental DNA is unavailable., Methods: We have applied linked-read WGS to identify novel causes of Meier-Gorlin syndrome (MGORS), a condition recognised by short stature, microtia and patella hypo/aplasia. There are eight genes associated with MGORS to date, all encoding essential components involved in establishing and initiating DNA replication., Results: Our successful phasing of linked-read data led to the identification of biallelic rare variants in four individuals (24% of our cohort) in DONSON , a recently established DNA replication fork surveillance factor. The variants include five novel missense and one deep intronic variant. All were demonstrated to be deleterious to function; the missense variants all disrupted the nuclear localisation of DONSON, while the intronic variant created a novel splice site that generated an out-of-frame transcript with no residual canonical transcript produced., Conclusion: Variants in DONSON have previously been associated with extreme microcephaly, short stature and limb anomalies and perinatal lethal microcephaly-micromelia syndrome. Our novel genetic findings extend the complicated spectrum of phenotypes associated with DONSON variants and promote novel hypotheses for the role of DONSON in DNA replication. While our findings reiterate that MGORS is a disorder of DNA replication, the pathophysiology is obviously complex. This successful identification of a novel disease gene for MGORS highlights the utility of linked-read WGS as a successful technology to be considered in the genetic studies of recessive conditions., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY. Published by BMJ.)

Background: HIV-infected, postpartum women on antiretroviral therapy (ART) have high rates of viremia. We examined predictors of postpartum viremia in the PROMISE study., Methods: Women with pre-ART CD4 T-cell counts ≥400 cells/mm who started ART during pregnancy were randomized postpartum to continue ART (CTART) or discontinue ART (DCART). Viral load and self-reported adherence were collected every 12 weeks, up to 144 weeks. Women in DCART reinitiated therapy when clinically indicated. Viremia was defined as 2 consecutive viral loads >1000 copies/mL after 24 weeks on ART. Adherence was dichotomized as missing versus not missing ART doses in the past 4 weeks. Predictors of viremia were examined using Cox proportional hazards regression with adherence as a time-varying covariate., Results: Among 802 women in the CTART arm, median age at entry was 27 years and median CD4 T-cell count 696 cells/mm. Of 175 women in CTART with viremia (22%), 141 had resistance data, and 12% had resistance to their current regimen. There was an estimated 0.12 probability of viremia by week 48 and 0.25 by week 144. Predictors of viremia included missed ART doses within the past 4 weeks, younger age, shorter duration of pre-entry ART, and being from the South American/Caribbean region. Of 137 women in DCART who reinitiated therapy, probability of viremia was similar to CTART (0.24 by week 96; 0.27 by week 144)., Conclusions: Rates of postpartum viremia are high and viremia is more likely in younger postpartum women who start ART later in pregnancy. Interventions should target these higher-risk women.

Background: The aetiology of bone marrow oedema-like abnormalities (BMOA) seen on magnetic resonance imaging (MRI) is as yet not fully understood. The current study aimed to investigate the potential of projection radiography and Raman microspectroscopy to provide information regarding the underlying physiological changes associated with BMOA in equine bone samples., Methods: MRI was used to assess 65 limbs from 43 horses. A subset of 13 limbs provided 25 samples, 8 with BMOA present and 17 as controls; these were examined with projection radiography to assess bone mineral density and Raman spectroscopy to assess bone composition. Statistical analysis was conducted using SPSS, the relationship between BMOA and age was tested using binary logistic regression, other outcome measures via unpaired t-tests., Results: Overall BMOA was found to be associated with locally increased bone density (p = 0.011), suggesting increased bone formation; however, no measurable changes relating to bone remodelling were found, and there were no detectable changes in the chemical composition of bone., Conclusions: BMOA is associated with locally increased bone density, without an associated change in the chemical composition of bone, suggesting this is not linked to BMOA. The presence of increased bone density associated with BMOA does appear to suggest that an increased amount of bone formation is occurring in these regions, but as Raman microspectroscopy data do not demonstrate any significant changes in bone chemical composition associated with BMOA, it would appear that the increased bone volume is due to a greater amount of bone being formed rather than an imbalance in relation to bone remodelling. The study provides a proof of principle for the use of Raman microspectroscopy and projection radiography in in vitro studies of BMOA.

We sought to define the genomic landscape of diffuse large B-cell lymphoma (DLBCL) by using formalin-fixed paraffin-embedded (FFPE) biopsy specimens. We used targeted sequencing of genes altered in hematologic malignancies, including DNA coding sequence for 405 genes, noncoding sequence for 31 genes, and RNA coding sequence for 265 genes (FoundationOne-Heme). Short variants, rearrangements, and copy number alterations were determined. We studied 198 samples (114 de novo, 58 previously treated, and 26 large-cell transformation from follicular lymphoma). Median number of GAs per case was 6, with 97% of patients harboring at least one alteration. Recurrent GAs were detected in genes with established roles in DLBCL pathogenesis (e.g. MYD88, CREBBP, CD79B, EZH2), as well as notable differences compared to prior studies such as inactivating mutations in TET2 (5%). Less common GAs identified potential targets for approved or investigational therapies, including BRAF, CD274 (PD-L1), IDH2, and JAK1/2. TP53 mutations were more frequently observed in relapsed/refractory DLBCL, and predicted for lack of response to first-line chemotherapy, identifying a subset of patients that could be prioritized for novel therapies. Overall, 90% (n = 169) of the patients harbored a GA which could be explored for therapeutic intervention, with 54% (n = 107) harboring more than one putative target.

In mouse models used to study parturition or pre-clinical therapeutic testing, measurement of uterine contractions is limited to either ex vivo isometric tension or operative intrauterine pressure (IUP). The goal of this study was to: (1) develop a method for transcervical insertion of a pressure catheter to measure in vivo intrauterine contractile pressure during mouse pregnancy, (2) determine whether this method can be utilized numerous times in a single mouse pregnancy without affecting the timing of delivery or fetal outcome and (3) compare the in vivo contractile activity between mouse models of term and preterm labor (PTL). Visualization of the cervix allowed intrauterine pressure catheter (IUPC) placement into anesthetized pregnant mice (plug = day 1, delivery = day 19.5). The amplitude, frequency, duration and area under the curve (AUC) of IUP was lowest on days 16-18, increased significantly ( P  < 0.05) on the morning of day 19 and reached maximal levels during by the afternoon of day 19 and into the intrapartum period. An AUC threshold of 2.77 mmHg discriminated between inactive labor (day 19 am) and active labor (day 19 pm and intrapartum period). Mice examined on a single vs every experimental timepoint did not have significantly different IUP, timing of delivery, offspring number or fetal/neonatal weight. The IUP was significantly greater in LPS-treated and RU486-treated mouse models of PTL compared to time-matched vehicle control mice. Intrapartum IUP was not significantly different between term and preterm mice. We conclude that utilization of a transcervical IUPC allows sensitive assessment of in vivo uterine contractile activity and labor progression in mouse models without the need for operative approaches., (© 2018 Society for Reproduction and Fertility.)

Background: Physical inactivity is a highly modifiable risk factor for the development of osteoporosis but, due to a lack of research that has precisely and objectively meaured physical activity (PA) relevant to bone, the specific contribution that PA can make to bone health is poorly understood. This study examined whether a more precise measure of PA relelvant to bone was associated with meaures of bone health in pre- and post-menopausal women in UK Biobank., Methods: Time spent at intensities specific to bone health [≥750 milli-gravitational units (mg) and ≥1000 mg] were analysed from raw tri-axial acceleration data averaged over 1-second epochs from 7-day monitoring of habitual PA using accelerometry-based activity monitors (100 Hz; AX3, Axivity, UK) of 1218 pre- and 1316 post-menopausal healthy women. In a cross-sectional analysis, associations between categories of time (<1, 1-2 and ≥2 minutes) spent above the intensity thresholds and calcaneal quantitative ultrasound measures of bone health (bone mineral density T-score, BMDT-score; speed of sound, SOS; and broadband ultrasound attenuation, BUA) were examined., Results: Compared with <1 minute, spending 1-2 or ≥2 minutes/day at intensities ≥1000 mg in pre-menopausal and ≥750 mg in post-menopausal women was positively associated with BMDT-score, SOS and BUA., Conclusion: Brief bursts of high-intensity PA relevant to bone health can be captured by applying bone-specific thresholds of intensity to raw tri-axial accelerations averaged over 1-second epochs. Accumulating 1-2 minutes/day of high-intensity PA, equivalent to running in pre-menopausal women and slow jogging in post-menopausal women, is associated with better bone health., (© The Author 2017; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association)

Adolescence is a crucial period for bone development, and exercise can enhance bone acquisition during this period of life. However, it is not known how the different loading sports practiced can affect bone acquisition in adolescent male athletes. Therefore, the purpose of the present study was to determine the 1-year longitudinal bone acquisition among adolescent males involved in osteogenic (football) and non-osteogenic (swimming and cycling) sports and to compare with active controls. A total of 116 adolescent males aged 12 to 14 years at baseline were followed for 1 year: 37 swimmers, 37 footballers, 28 cyclists, and 14 active controls. Bone mineral content (BMC) was assessed using dual-energy X-ray absorptiometry (DXA); cross-sectional area (CSA), cross-sectional moment of inertia (CSMI), and section modulus (Z) at the femoral neck was assessed using hip structural analysis (HSA); and bone texture of the lumbar spine was assessed using trabecular bone score (TBS). Serum N-terminal propeptide of procollagen type I (PINP), isomer of the Carboxi-terminal telopeptide of type 1 collagen (CTX-I), total serum calcium, and 25 hydroxyvitamin D [25(OH)D] were analyzed. Footballers had significantly higher adjusted BMC at the lumbar spine (7.0%) and femoral neck (5.0%) compared with cyclists, and significantly greater BMC at the lumbar spine (6.9%) compared with swimmers. Footballers presented significantly greater TBS (4.3%) compared with swimmers, and greater CSMI (10.2%), CSA (7.1%), Z (8.9%) and TBS (4.2%) compared with cyclists. No differences were noted between cyclists and swimmers, both groups had similar bone acquisition compared with controls. PINP was significantly higher in footballers and controls compared with cyclists and swimmers (3.3% to 6.0%), and 25(OH)D was significantly higher in footballers and cyclists compared with swimmers and controls (9.9% to 13.1%). These findings suggest that bone acquisition is higher in adolescent male footballers compared with swimmers and cyclists at the femoral neck and lumbar spine sites of the skeleton. © 2017 American Society for Bone and Mineral Research., (© 2017 American Society for Bone and Mineral Research.)

Purpose: The determinants of areal bone mineral density (aBMD) and hip geometry estimates in adolescent athletes are poorly understood. This study aimed to identify the determinants of aBMD and hip geometry estimates in adolescent male athletes., Methods: One hundred twenty-one men (13.1 ± 0.1 yr) were measured: 41 swimmers, 37 footballers, 29 cyclists, and 14 controls. Dual energy X-ray absorptiometry measured aBMD at lumbar spine, femoral neck and total body. Hip structural analysis evaluated hip geometry estimates at the femoral neck. Multiple linear regression examined the contribution of the sports practised, stature, lean and fat mass, serum calcium and vitamin D, moderate to vigorous physical activity, vertical jump and cardiorespiratory fitness with aBMD and hip geometry estimates., Results: Region-specific lean mass was the strongest positive predictor of aBMD (β = 0.614-0.931) and football participation was the next strongest predictor (β = 0.304-0.579). Stature (β = 0.235-0.380), fat mass (β = 0.189), serum calcium (β = 0.103), serum vitamin D (β = 0.104-0.139), and vertical jump (β = 0.146-0.203) were associated with aBMD across various specific sites. All hip geometry estimates were associated with lean mass (β = 0.370 - 0.568) and stature (β = 0.338-0.430). Football participation was associated with hip cross-sectional area (β = 0.322) and moderate to vigorous physical activity (β = 0.140-0.142). Cardiorespiratory fitness (β = 0.183-0.207) was associated with section modulus and cross-sectional moment of inertia., Conclusions: Region-specific lean mass is the strongest determinant of aBMD and hip geometry estimates in adolescent male athletes. Football participation and stature were important determinants for aBMD and hip geometry estimates, whereas the contribution of the other predictors was site specific.

Purpose: Exercise is an effective approach for developing bone mass and adolescence is a key period to optimize bone health. However, sports-specific training may have different effects on bone outcomes. This study examined the differences on bone outcomes between osteogenic (football) and nonosteogenic (swimming and cycling) sports and a control group in male adolescents., Methods: One hundred twenty one males (13.1 ± 0.1 yr) were measured: 41 swimmers, 37 footballers, 29 cyclists, and 14 controls. Dual energy X-ray absorptiometry measured bone mineral density (BMD) and bone mineral content at lumbar spine, right and left hip, and total body. Hip Structural Analysis evaluated bone geometry at the femoral neck. Quantitative ultrasound evaluated bone stiffness at both feet., Results: Footballers had significantly higher BMD at total body less head (7%-9%), total hip (12%-21%), and legs (7%-11%) compared with all groups and significantly higher BMD at the femoral neck than controls (14%). Cyclists had higher BMD at the trochanter (10%) and bone mineral content at the arms (10%) compared with controls. Geometrical analysis showed that footballers had significantly higher cross-sectional area (8%-19%) compared with all groups, cross-sectional moment of inertia (17%) compared with controls and section modulus compared with cyclists (11%) and controls (21%). Footballers had significantly higher bone stiffness compared with all groups (10%-20%) at the dominant foot and (12%-13%) at the nondominant foot compared with swimmers and controls., Conclusions: Adolescent male footballers exhibited higher bone density, geometry, and stiffness compared with swimmers, cyclists and controls. Although swimmers and cyclists had higher bone outcomes compared with controls, these differences were not significant.

Genomic studies have identified recurrent somatic mutations in acute leukemias. However, current murine models do not sufficiently encompass the genomic complexity of human leukemias. To develop preclinical models, we transplanted 160 samples from patients with acute leukemia (acute myeloid leukemia, mixed lineage leukemia, B-cell acute lymphoblastic leukemia, T-cell ALL) into immunodeficient mice. Of these, 119 engrafted with expected immunophenotype. Targeted sequencing of 374 genes and 265 frequently rearranged RNAs detected recurrent and novel genetic lesions in 48 paired primary tumor (PT) and patient-derived xenotransplant (PDX) samples. Overall, the frequencies of 274 somatic variant alleles correlated between PT and PDX samples, although the data were highly variable for variant alleles present at 0-10%. Seventeen percent of variant alleles were detected in either PT or PDX samples only. Based on variant allele frequency changes, 24 PT-PDX pairs were classified as concordant while the other 24 pairs showed various degree of clonal discordance. There was no correlation of clonal concordance with clinical parameters of diseases. Significantly more bone marrow samples than peripheral blood samples engrafted discordantly. These data demonstrate the utility of developing PDX banks for modeling human leukemia, and emphasize the importance of genomic profiling of PDX and patient samples to ensure concordance before performing mechanistic or therapeutic studies., Competing Interests: KW, MKN, JH, ALD, GMF, DL, SR, PJS, EMS, TB, GAO, RY, VAM are employees and equity holders, RLL is a consultant for Foundation Medicine, Inc.

The spectrum of somatic alterations in hematologic malignancies includes substitutions, insertions/deletions (indels), copy number alterations (CNAs), and a wide range of gene fusions; no current clinically available single assay captures the different types of alterations. We developed a novel next-generation sequencing-based assay to identify all classes of genomic alterations using archived formalin-fixed paraffin-embedded blood and bone marrow samples with high accuracy in a clinically relevant time frame, which is performed in our Clinical Laboratory Improvement Amendments-certified College of American Pathologists-accredited laboratory. Targeted capture of DNA/RNA and next-generation sequencing reliably identifies substitutions, indels, CNAs, and gene fusions, with similar accuracy to lower-throughput assays that focus on specific genes and types of genomic alterations. Profiling of 3696 samples identified recurrent somatic alterations that impact diagnosis, prognosis, and therapy selection. This comprehensive genomic profiling approach has proved effective in detecting all types of genomic alterations, including fusion transcripts, which increases the ability to identify clinically relevant genomic alterations with therapeutic relevance., (© 2016 by The American Society of Hematology.)

We aimed to study whether short-duration vibration exercise or football sessions of two different durations acutely changed plasma markers of bone turnover and muscle strain. Inactive premenopausal women ( n = 56) were randomized to complete a single bout of short (FG15) or long duration (FG60) small sided football or low magnitude whole body vibration training (VIB). Procollagen type 1 amino-terminal propeptide (P1NP) was increased during exercise for FG15 (51.6 ± 23.0 to 56.5 ± 22.5  μ g·L -1 , mean ± SD, P < 0.05) and FG60 (42.6 ± 11.8 to 50.2 ± 12.8  μ g·L -1 , P < 0.05) but not for VIB (38.8 ± 15.1 to 36.6 ± 14.7  μ g·L -1 , P > 0.05). An increase in osteocalcin was observed 48 h after exercise ( P < 0.05), which did not differ between exercise groups. C-terminal telopeptide of type 1 collagen was not affected by exercise. Blood lactate concentration increased during exercise for FG15 (0.6 ± 0.2 to 3.4 ± 1.2 mM) and FG60 (0.6 ± 0.2 to 3.3 ± 2.0 mM), but not for VIB (0.6 ± 0.2 to 0.8 ± 0.4 mM) ( P < 0.05). Plasma creatine kinase increased by 55 ± 63% and 137 ± 119% 48 h after FG15 and FG60 ( P < 0.05), but not after VIB (26 ± 54%, NS). In contrast to the minor elevation in osteocalcin in response to a single session of vibration exercise, both short and longer durations of small sided football acutely increased plasma P1NP, osteocalcin, and creatine kinase. This may contribute to favorable effects of chronic training on musculoskeletal health., Competing Interests: The authors declare that there is no conflict of interests in relation to the publication of this paper.

Background: Invasive mold infections (IMIs) are a leading cause of mortality in immunocompromised children, yet there has never been an international epidemiologic investigation of pediatric IMIs., Methods: This international, prospective cohort study was performed to characterize the epidemiology, antifungal therapy, and outcomes of pediatric IMIs. Children (≤18 years) with proven or probable IMIs were enrolled between August 2007 and May 2011 at 22 sites. Risk factors, underlying diagnoses, and treatments were recorded. Outcomes were assessed at 12 weeks after diagnosis using European Organization for Research and Treatment of Cancer/Mycoses Study Group response criteria., Results: One hundred thirty-one pediatric patients with IMIs were enrolled; the most common IMI was invasive aspergillosis ([IA] 75%). Children with IA and those with other types of IMIs had similar underlying risk factors, except that children with IMIs caused by non-Aspergillus species were more likely to have received mold-active antifungal agents preceding diagnosis. The most commonly used antifungal classes after diagnosis were triazoles (82%) and polyenes (63%). Combination therapy was used in 53% of patients. Use of combination therapy was associated with an increased risk of adverse events (risk ratio, 1.98; 95% confidence interval, 1.06-3.68; P = .031), although there was no detectable difference in outcome., Conclusions: Although risk factors for IMIs are similar across specific subtypes, preceding antifungal therapy may be an important modifier. Combination antifungal therapy requires further study to determine its true risks and benefits., (© The Author 2014. Published by Oxford University Press on behalf of the Pediatric Infectious Diseases Society. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)

The chemokine binding protein (CKBP) from orf virus (ORFV) binds with high affinity to chemokines from three classes, C, CC, and CXC, making it unique among poxvirus CKBPs described to date. We present its crystal structure alone and in complex with three CC chemokines, CCL2, CCL3, and CCL7. ORFV CKBP possesses a β-sandwich fold that is electrostatically and sterically complementary to its binding partners. Chemokines bind primarily through interactions involving the N-terminal loop and a hydrophobic recess on the ORFV CKBP β-sheet II surface, and largely polar interactions between the chemokine 20s loop and a negatively charged surface groove located at one end of the CKBP β-sheet II surface. ORFV CKBP interacts with leukocyte receptor and glycosaminoglycan binding sites found on the surface of bound chemokines. SEC-MALLS and chromatographic evidence is presented supporting that ORFV CKBP is a dimer in solution over a broad range of protein concentrations., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Background: Osteoporosis is a skeletal disease associated with high morbidity, mortality and increased economic costs. Early prevention during adolescence appears to be one of the most beneficial practices. Exercise is an effective approach for developing bone mass during puberty, but some sports may have a positive or negative impact on bone mass accrual. Plyometric jump training has been suggested as a type of exercise that can augment bone, but its effects on adolescent bone mass have not been rigorously assessed. The aims of the PRO-BONE study are to: 1) longitudinally assess bone health and its metabolism in adolescents engaged in osteogenic (football), non-osteogenic (cycling and swimming) sports and in a control group, and 2) examine the effect of a 9 month plyometric jump training programme on bone related outcomes in the sport groups., Methods/design: This study will recruit 105 males aged 12-14 years who have participated in sport specific training for at least 3 hours per week during the last 3 years in the following sports groups: football (n = 30), cycling (n = 30) and swimming (n = 30). An age-matched control group (n = 15) that does not engage in these sports more than 3 hours per week will also be recruited. Participants will be measured on 5 occasions: 1) at baseline; 2) after 12 months of sport specific training where each sport group will be randomly allocated into two sub-groups: intervention group (sport + plyometric jump training) and sport group (sport only); 3) exactly after the 9 months of intervention; 4) 6 months following the intervention; 5) 12 months following the intervention. Body composition (dual energy X-ray absorptiometry, air displacement plethysmography and bioelectrical impedance), bone stiffness index (ultrasounds), physical activity (accelerometers), diet (24 h recall questionnaire), pubertal maturation (Tanner stage), physical fitness (cardiorespiratory and muscular), bone turnover markers and vitamin D will be measured at each visit., Discussion: The PRO-BONE study is designed to investigate the impact of osteogenic and non-osteogenic sports on bone development in adolescent males during puberty, and how a plyometric jump training programme is associated with body composition parameters.

Understanding practice behaviors of solo/dual physician ownership and associated factors at the national level is important information for policymakers and clinicians in response to the Affordable Care Act (ACA) of 2010, but poorly understood in the literature. We analyzed nationally representative data (n = 4,720). The study results reveal nearly 33% of the sample reported solo/two-physician practices. Male/minority/older physicians, psychiatrists, favor small practices. Greater market competition was perceived and less charity care was given among solo/two-physician practitioners. The South region was favored by small physician practitioners. Physicians in solo or two-person practices provided fewer services to chronic patients and were dissatisfied with their overall career in medicine. Small practices were favored by international medical graduates (IMGs) and primary care physicians (PCPs). Overall our data suggest that the role of solo/dual physician practices is fading away in the delivery of medicine. Our findings shed light on varied characteristics and practice behaviors of solo/two-physician practitioners, but more research may be needed to reevaluate the potential role of small physician practitioners and find a way to foster a private physician practice model in the context of the newly passed ACA of 2010.

Antimicrobial peptides (AMPs) are promising leads for novel antibiotics; however, their activity is often compromised under physiological conditions. The purpose of this study was to determine the activity of α-peptide/β-peptoid peptidomimetics and AMPs against Escherichia coli and Staphylococcus aureus in the presence of human blood-derived matrices and immune effectors. The minimum inhibitory concentration (MIC) of two peptidomimetics against E. coli decreased by up to one order of magnitude when determined in 50% blood plasma as compared to MHB media. The MIC of a membrane-active AMP, LL-I/3, also decreased, whereas two intracellularly acting AMPs were not potentiated by plasma. Blood serum had no effect on activity against E. coli and neither matrix had an effect on activity against S. aureus. Unexpectedly, physiological concentrations of human serum albumin did not influence activity. Plasma potentiation was not mediated by an LL-37 analogue, lysozyme or hydrogen peroxide; however, plasma potentiation of activity was abolished when the complement system was heat-inactivated. Time-course experiments indicated that potentiation was due to plasma-mediated effects on bacterial cells prior to activities of peptidomimetics. The unexpected enhancement of antibacterial activity of peptidomimetics and AMPs under physiological conditions significantly increases the therapeutic potential of these compounds., (Copyright © 2013 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.)

A previous modelling study predicted that the forces applied by the extensor muscles to stabilise the lumbar spine would be greater in spines that have a larger sagittal curvature (lordosis). Because the force-generating capacity of a muscle is related to its size, it was hypothesised that the size of the extensor muscles in a subject would be related to the size of their lumbar lordosis. Magnetic resonance imaging (MRI) data were obtained, together with age, height, body mass and back pain status, from 42 female subjects. The volume of the extensor muscles (multifidus and erector spinae) caudal to the mid-lumbar level was estimated from cross-sectional area measurements in axial T1-weighted MRIs spanning the lumbar spine. Lower lumbar curvature was determined from sagittal T1-weighted images. A stepwise linear regression model was used to determine the best predictors of muscle volume. The mean lower lumbar extensor muscle volume was 281 cm(3) (SD = 49 cm(3)). The mean lower lumbar curvature was 30 ° (SD = 7 °). Five subjects reported current back pain and were excluded from the regression analysis. Nearly half the variation in muscle volume was accounted for by the variables age (standardised coefficient, B = -3.2, P = 0.03) and lower lumbar curvature (B = 0.47, P = 0.002). The results support the hypothesis that extensor muscle volume in the lower lumbar spine is related to the magnitude of the sagittal curvature; this has implications for assessing muscle size as an indicator of muscle strength., (© 2013 Anatomical Society.)

Eukaryotic ecto-5'-nucleotidase (e5NT) catalyses the hydrolysis of extracellular AMP to adenosine and plays a pivotal role in switching on adenosine signalling via the P1 receptors of the purinergic signalling pathway. With such an important regulatory role, e5NT has become an appealing new drug target, with potential applications in the treatment of inflammation, chronic pain, hypoxia and cancer. In order to gain insight into the structure and function of the eukaryotic e5NT enzymes and to assist in structure-based drug design, the crystal structure of human e5NT has been solved. Recombinant human e5NT comprising four asparagine-to-aspartate surface mutations targeting potential glycosylation sites was refolded from bacterial inclusion bodies. Refolded and purified human e5NT crystallized in space group P4(3)32 and a data set to 1.85 Å resolution was obtained. The structure could be solved by molecular replacement using a polyalanine model generated from Thermus thermophilus 5'-nucleotidase (5NT). An anomalous data set revealed the presence of a metal-ion binding site, as well as calcium and chloride ion-binding sites. Structural comparisons with bacterial 5NT homologues showed that the human e5NT crystal structure has an open conformation in which the metal- and substrate-binding sites are distant from each other. Here, the crystallization and preliminary X-ray crystallographic analysis of an open structural conformation of human e5NT are described.

Background: Characterization and use of antimicrobial peptides (AMPs) requires that their mode of action is determined. The interaction of membrane-active peptides with their target is often established using model membranes, however, the actual permeabilization of live bacterial cells and subsequent killing is usually not tested. In this report, six α-peptide/β-peptoid chimeras were examined for the effect of amino acid/peptoid substitutions and chain length on the membrane perturbation and subsequent killing of food-borne and clinical bacterial isolates., Results: All six AMP analogues inhibited growth of twelve food-borne and clinical bacterial strains including Extended Spectrum Beta-Lactamase-producing Escherichia coli. In general, the Minimum Inhibitory Concentrations (MIC) against Gram-positive and -negative bacteria were similar, ranging from 1 to 5 μM. The type of cationic amino acid only had a minor effect on MIC values, whereas chain length had a profound influence on activity. All chimeras were less active against Serratia marcescens (MICs above 46 μM). The chimeras were bactericidal and induced leakage of ATP from Staphylococcus aureus and S. marcescens with similar time of onset and reduction in the number of viable cells. EDTA pre-treatment of S. marcescens and E. coli followed by treatment with chimeras resulted in pronounced killing indicating that disintegration of the Gram-negative outer membrane eliminated innate differences in susceptibility. Chimera chain length did not influence the degree of ATP leakage, but the amount of intracellular ATP remaining in the cell after treatment was influenced by chimera length with the longest analogue causing complete depletion of intracellular ATP. Hence some chimeras caused a complete disruption of the membrane, and this was parallel by the largest reduction in number of viable bacteria., Conclusion: We found that chain length but not type of cationic amino acid influenced the antibacterial activity of a series of synthetic α-peptide/β-peptoid chimeras. The synthetic chimeras exert their killing effect by permeabilization of the bacterial cell envelope, and the outer membrane may act as a barrier in Gram-negative bacteria. The tolerance of S. marcescens to chimeras may be due to differences in the composition of the lipopolysaccharide layer also responsible for its resistance to polymyxin B.

This review of quantitative ultrasound (QUS) and bone health uses the current literature to summarise the clinical and research effectiveness of QUS. QUS has been demonstrated to have the ability to predict fracture, particularly at the hip. However, the magnitude of prediction is fracture-site, measurement-site and device dependent. The correlations between dual X-ray absorptiometry (DXA) and bone mineral density (BMD) are weak to moderate, resulting in different subjects being identified as being at risk of fracture by the two different methods. QUS is sensitive to age and menopause-related changes and to clinical risk factors and lifestyle factors associated with osteoporosis. Whilst a limited ability of QUS to monitor therapeutic intervention has been demonstrated, this is still an area where it's poorer precision, in comparison to DXA, results in limited applicability. Whilst DXA remains the gold standard for the diagnosis of osteoporosis, QUS may be of use for the prediction of those at risk of future fracture in areas where there is limited availability of DXA.

Zidovudine (ZDV) and lamivudine (3TC) metabolism to triphosphates (TP) is necessary for antiviral activity. The aims of this study were to compare ZDV-TP and 3TC-TP concentrations in adolescents receiving twice daily (BID) and once daily (QD) regimens and to determine the metabolite concentrations of ZDV and 3TC during chronic therapy on a QD regimen. Human immunodeficiency virus-infected patients (12 to 24 years) taking ZDV (600 mg/day) and 3TC (300 mg/day) as part of a highly active antiretroviral therapy regimen received QD and BID regimens of ZDV and 3TC for 7 to 14 days in a crossover design. Serial blood samples were obtained over 24 h on the QD regimen. Intracellular mono-, di-, and triphosphates for ZDV and 3TC were measured. The median ratio of BID/QD for ZDV-TP predose concentrations was 1.28 (95% confidence interval [CI] = 1.00 to 2.45) and for 3TC-TP was 1.12 (95% CI = 0.81 to 1.96). The typical population estimated half-lives (+/- the standard error of the mean) were 9.1 +/- 0.859 h for ZDV-TP and 17.7 +/- 2.8 h for 3TC-TP. Most patients had detectable levels of the TP of ZDV (24 of 27) and 3TC (24 of 25) 24 h after dosing, and half-lives on a QD regimen were similar to previously reported values when the drugs were given BID. Lower, but not significantly different, concentrations of ZDV-TP were demonstrated in the QD regimen compared to the BID regimen (P = 0.056). Although findings were similar between the BID and QD groups, the lower concentrations of ZDV and the number of patients below the level of detection after 24 h suggests that ZDV should continue to be administered BID.

Objective: To determine regional differences in the orientation of collagen in the articular cartilage of the equine metacarpophalangeal joint as well as describing cartilage orientation in lesions using small angle X-ray scattering (SAXS)., Design: SAXS diffraction patterns were taken at the European Synchrotron Radiation Facility (ESRF), with increasing depth into cartilage and bone cross sections. Results for healthy samples were taken at different regions along the joint which receive different loads and differences in collagen orientation were determined. Results were also taken from diseased samples and the collagen orientation changes from that of healthy samples observed., Results: Regions subject to low loads show a lower degree of orientation and regions exposed to the highest loads possess oriented collagen fibres especially in the radial layer. In early lesions the orientations of the collagen fibres are disrupted. Subchondral bone fibres are twisted in regions where the joint receives shear forces. Changes in fibre orientation are also observed in the calcified cartilage even in regions where the cartilage is intact. In more advanced lesions where there is loss of cartilage the fibres in the calcified layer are realigned tangential to the surface., Conclusions: Regional variations in collagen arrangement show that the highly ordered layers of the articular cartilage are the most important elements in supporting high variable loads. In lesions changes occur in the deep tissue whilst the overlying cartilage appeared normal. We therefore suggest that the interface region is a key element in the early stages of the disease.

We describe the case of a patient with improving invasive aspergillosis and paradoxically rising serum galactomannan levels in the presence of chronic renal failure and ongoing hemodialysis. Dialysate tested negative for galactomannan, demonstrating the inability of treatments such as hemodialysis to clear Aspergillus antigen from serum. In patients with renal failure and aspergillosis, rising serum galactomannan levels may not necessarily signify progressive infection.

vav1 has been shown to play a key role in lymphocyte development and activation, but its potential importance in macrophage activation has received little attention. We have previously reported that exposure of macrophages to bacterial lipopolysaccharide (LPS) leads to increased activity of hck and other src-related tyrosine kinases and to the prompt phosphorylation of vav1 on tyrosine. In this study, we tested the role of vav1 in macrophage responses to LPS, focusing on the upregulation of nuclear factor for interleukin-6 expression (NF-IL-6) activity and inducible nitric oxide synthase (iNOS) protein accumulation in RAW-TT10 murine macrophages. We established a series of stable cell lines expressing three mutant forms of vav1 in a tetracycline-regulatable fashion: (i) a form producing a truncated protein, vavC; (ii) a form containing a point mutation in the regulatory tyrosine residue, vavYF174; and (iii) a form with an in-frame deletion of 6 amino acids required for the guanidine nucleotide exchange factor (GEF) activity of vav1 for rac family GTPases, vavGEFmt. Expression of the truncated mutant (but not the other two mutants) has been reported to interfere with T-cell activation. In contrast, we now demonstrate that expression of any of the three mutant forms of vav1 in RAW-TT10 cells consistently inhibited LPS-mediated increases in iNOS protein accumulation and NF-IL-6 activity. These data provide direct evidence for a role for vav1 in LPS-mediated macrophage activation and iNOS production and suggest that vav1 functions in part via activation of NF-IL-6. Furthermore, these findings indicate that the GEF activity of vav1 is required for its ability to mediate macrophage activation by LPS.

The CYP 17 and CYP 19 genes encode 17alpha-hydroxylase/17,20-lyase and aromatase, respectively, both involved in sex hormone synthesis. We investigated the association between 2 common polymorphisms in 1) the promoter region (T-->C substitution) of CYP 17, and 2) exon 3 (G-->A) of CYP 19, bone mineral density (BMD) and serum androgen/estradiol, in a case-control study of 252 postmenopausal women aged 64.5 +/- 9.2 yr (mean +/- SD). There was no significant difference in serum estradiol concentrations between cases (n = 136) and controls (n = 116). The CYP 19 genotype was significantly associated with serum estradiol (P = 0.002). Women with the AA genotype had higher serum estradiol concentrations compared with those with the GG genotype (P = 0.03). In older women, those with the CYP 19 GA and GG genotypes had an increased prevalence of osteoporosis (P = 0.04) and fractures (P = 0.003). We found no significant association between CYP 17 genotype and serum androgens and estradiol concentrations. However, a significant association was seen between BMD values at the femoral neck with CYP 17 genotype in cases (P = 0.04) and in the whole study population (P = 0.012). Subjects with the CC genotype had significantly lower BMD (mean +/- SD: TT, 0.7 +/- 0.16; CC, 0.6 +/- 0.08 g/cm(2); P = 0.006). In conclusion, both CYP 17 and CYP 19 are candidate genes for osteoporosis in postmenopausal women.

Unlabelled: Combining information from different types of BMD measurement should improve the evaluation of patients' risk of fracture. This study used a bivariate gaussian model to examine the effect of combining two different BMD measurements. The results show that, in practice, there is little benefit unless the measurements are completely unrelated., Introduction: Intuitively, the combination of information from two or more different types of bone densitometry investigation should improve our ability to identify patients at high risk of fracture. However, the best way to combine measurements and the resulting gain in fracture discrimination are not known., Materials and Methods: In this study, we used a bivariate gaussian model to investigate the effect of combining two different types of bone densitometry measurements. The measurements had individual relative risk values RR1 and RR2 and a correlation coefficient r between their Z-scores. Different approaches to the combination of the two measurements were compared by calculating the area under the curve (AUC) for the receiver operating characteristic (ROC) curve, which was obtained by plotting the percentage of fracture patients against the percentage of the whole population with a Z-score below some chosen threshold. ROC curves were calculated for three cases: (1) one type of measurement only; (2) two different types of measurements combined using their mean Z-score weighted according to the theoretical optimum weighting factors predicted by the bivariate gaussian model; and (3) two different types of measurements combined using the conventional World Health Organization (WHO) approach, where one or other measurement is below a set threshold. The theoretical model was tested using measurements of speed of sound (SOS) in the radius, phalanx, and metatarsal in patients with vertebral and Colles' fractures., Results: Results were calculated for RR values of 1.5, 2.0, and 2.5 and r = 0, 0.5, and 0.7. Although a significant improvement in fracture discrimination was obtained when r = 0 and RR1 = RR2, the improvements obtained when r > or = 0.5 or RR1 double dagger RR2 were relatively modest. Slightly better fracture discrimination was obtained using the weighted mean Z-score approach compared with the WHO approach, although the differences were small. The results of the in vivo study in Colles' and vertebral fracture patients showed close agreement with the predictions of the bivariate gaussian model., Conclusion: In practice, from a theoretical point of view, there is unlikely to be any benefit from combining information from different types of bone densitometry measurements unless they are completely unrelated.

Unlabelled: The genetic influences of speed of sound (SOS) and BMD were evaluated using 215 pairs of healthy female twins. Genetic influences were found for all SOS and BMD measurements. A combination of shared and unique genetic influences was found to control BMD and SOS at the radius., Introduction: The aim of this study was to investigate to what extent axial transmission speed of sound (SOS) measurements in cortical bone at multiple, peripheral skeletal sites will be influenced by genetic factors and to estimate the proportion of shared and unique genetic influences controlling bone mineral density (BMD) and SOS at a single site, the radius., Materials and Methods: The study population consisted of 215 pairs of healthy female twins. Of these, 85 pairs were monozygotic (MZ) and 130 pairs were dizygotic (DZ). The twins had measurements of the nondominant third proximal phalanx, one-third radius, midshaft tibia, and fifth metatarsal using the Sunlight Omnisense and DXA measurements of the lumbar spine, nondominant proximal femur, nondominant radius, and whole body using Hologic QDR-4500W densitometers. Calcaneal quantitative ultrasound (QUS) measurements were performed using the McCue CUBA clinical. Intraclass correlations were calculated, and heritability was estimated using multiple regression analysis. Bivariate analysis of site-matched SOS and BMD measurements at the radius was performed using a variance components analysis program., Results: Age- and body mass index-adjusted heritability estimates ranged from 0.51 (95% CI, 0.32-0.70) to 0.56 (0.37-0.76) for SOS measurements, 0.58 (0.41-0.75) for broadband ultrasound attenuation (BUA), 0.72 (0.58-0.86) to 0.77 (0.63-0.91) for axial BMD, and 0.53 (0.16-0.90) to 0.63 (0.26-1.00) for radius and whole body BMD. The correlation between SOS and DXA at the radius was r = 0.34 (0.29-0.47). Thirty-eight percent (16-57%) of the genetic variance explained by SOS at the radius was also explained by BMD (one-third radius region of interest), with 62% being unique., Conclusion: In conclusion, genetic influences were demonstrated for SOS measurements in cortical bone at multiple sites, axial BMD, calcaneal BUA, radius, and whole body BMD. At the radius, up to 38% of the genetic influence is shared by genes controlling BMD and SOS. Clarifying the site specificity and pleiotropic effects of bone genes should help our understanding of these complex pathways.

We describe 3 pediatric patients with cancer who had clinical and radiographic evidence of pneumonitis and for whom cultures of bronchoalveolar lavage fluid specimens yielded Ureaplasma urealyticum. Two of the patients died; for the surviving patient, clinical improvement coincided temporally with administration of erythromycin. Immunocompromised patients with pneumonitis of unclear etiology should have respiratory secretions cultured for mycoplasmas and should receive empiric therapy that includes a macrolide antibiotic.

In macrophages, bacterial lipopolysaccharide (LPS) has been noted to mimic certain effects of the sphingolipid ceramide, suggesting that ceramide may be involved in macrophage activation by LPS and/or that LPS utilizes ceramide-related signaling pathways. Putative downstream targets of ceramide include a ceramide-activated (serine/threonine) protein kinase (CAPK) and phosphatase (CAPP). However, the potential role of tyrosine phosphorylation pathways in macrophage response to ceramide has not been examined. Herein we report that cell-permeable analogs of ceramide up-regulate both inducible nitric oxide synthase (iNOS) and tumor necrosis factor (TNF) production in RAW 264.7 murine macrophages. Herbimycin A and genistein, potent natural inhibitors of protein tyrosine (but not serine/threonine) phosphorylation, block ceramide-induced iNOS and TNF production. Furthermore, the highly src-family selective pyrazolopyrimidine inhibitor PP1 also blocks ceramide-induced iNOS and TNF production in RAW 264.7 cells. We found that PP1 also inhibits ceramide-mediated tyrosine phosphorylation of the src-family kinase hck. These data indicate that src-related tyrosine kinases play a critical role in macrophage activation by ceramide.