Residual bone fragments in tibiofibular joint and postoperative local recurrence: an analysis of 21 cases of proximal fibular giant cell tumour

Background

Currently, there are no known reports on the aetiology of local giant cell tumour (GCT) recurrence in the proximal fibula following en bloc resection. We analysed 21 cases of proximal fibular GCT, focusing on the presence of residual bone in the tibiofibular joint, its causes and its impact on postoperative recurrence.

Methods

We retrospectively analysed 21 cases with proximal fibular GCT occurring between 2000 and 2017.

Results

There were 14 males and 7 females. The average patient age was 25.0 years. Seventeen patients were diagnosed and treated at our facility, while 4 were referred after local recurrence.Six patients presented with residual bone fragments in the tibiofibular joint during their first month of follow-up. Patients with residual bone fragments had a higher local recurrence rate (83.3%) than those without (0%, p?=?0.0003). Upon further analysis, patients with a preoperative Campanacci grade III tumour (p?=?0.0055) and pathological fractures (p?=?0.0109) were at a higher risk of exhibiting postoperative residual bone fragments.

Conclusions

The presence of residual bone fragments in the tibiofibular joint was the main cause of postoperative local recurrence. The presence of residual bone fragments may be related to the preoperative Campanacci grade and pathological fractures. Therefore, close attention should be paid to postoperative follow-up examinations, and if recurrence is suspected, surgical resection should be planned.

     

Resolution effects in reconstructing ancestral genomes

Background

The reconstruction of ancestral genomes must deal with the problem of resolution, necessarily involving a trade-off between trying to identify genomic details and being overwhelmed by noise at higher resolutions.

Results

We use the median reconstruction at the synteny block level, of the ancestral genome of the order Gentianales, based on coffee, Rhazya stricta and grape, to exemplify the effects of resolution (granularity) on comparative genomic analyses.

Conclusions

We show how decreased resolution blurs the differences between evolving genomes, with respect to rate, mutational process and other characteristics.

     

Optimization of fecal sample preparation for untargeted LC-HRMS based metabolomics

Introduction

Collecting feces is easy. It offers direct outcome to endogenous and microbial metabolites.

Objectives

In a context of lack of consensus about fecal sample preparation, especially in animal species, we developed a robust protocol allowing untargeted LC-HRMS fingerprinting.

Methods

The conditions of extraction (quantity, preparation, solvents, dilutions) were investigated in bovine feces.

Results

A rapid and simple protocol involving feces extraction with methanol (1/3, M/V) followed by centrifugation and a step filtration (10 kDa) was developed.

Conclusion

The workflow generated repeatable and informative fingerprints for robust metabolome characterization.

     

Mitochondria-cytoskeleton associations in mammalian cytokinesis

Background

The role of the cytoskeleton in regulating mitochondrial distribution in dividing mammalian cells is poorly understood. We previously demonstrated that mitochondria are transported to the cleavage furrow during cytokinesis in a microtubule-dependent manner. However, the exact subset of spindle microtubules and molecular machinery involved remains unknown.

Methods

We employed quantitative imaging techniques and structured illumination microscopy to analyse the spatial and temporal relationship of mitochondria with microtubules and actin of the contractile ring during cytokinesis in HeLa cells.

Results

Superresolution microscopy revealed that mitochondria were associated with astral microtubules of the mitotic spindle in cytokinetic cells. Dominant-negative mutants of KIF5B, the heavy chain of kinesin-1 motor, and of Miro-1 disrupted mitochondrial transport to the furrow. Live imaging revealed that mitochondrial enrichment at the cell equator occurred simultaneously with the appearance of the contractile ring in cytokinesis. Inhibiting RhoA activity and contractile ring assembly with C3 transferase, caused mitochondrial mislocalisation during division.

Conclusions

Taken together, the data suggest a model in which mitochondria are transported by a microtubule-mediated mechanism involving equatorial astral microtubules, Miro-1, and KIF5B to the nascent actomyosin contractile ring in cytokinesis.

     

The role of bone marrow mononuclear cell-conditioned medium in the proliferation and migration of human dermal fibroblasts

Background

Several recent studies have demonstrated the great potential of bone marrow cells in regenerative medicine, not only for their ability to differentiate to match a damaged cell type, but also because they synthesize and release various growth factors and cytokines.We examined the effect of bone marrow cell-conditioned medium in the healing process, especially in terms of fibroblast proliferation and migration.

Methods

These in vitro studies consisted of co-culture (without direct contact) of dermal fibroblasts with mononuclear bone marrow cells and the use of conditioned medium obtained from these cultures in a scratch wound model.

Results

Mononuclear cells were found to increase the proliferation of fibroblasts, and the conditioned medium showed a stimulatory effect on the migration of fibroblasts.

Conclusion

When considered together with the observed increase in growth factor levels in conditioned medium, it appears that these cells act through a paracrine mechanism.

     

Weekly oral alendronate in mevalonate kinase deficiency

Background

Mevalonate kinase deficiency (MKD) is caused by mutations in the MVK gene, encoding the second enzyme of mevalonate pathway, which results in subsequent shortage of downstream compounds, and starts in childhood with febrile attacks, skin, joint, and gastrointestinal symptoms, sometimes induced by vaccinations.

Methods

For a history of early-onset corticosteroid-induced reduction of bone mineral density in a 14-year-old boy with MKD, who also had presented three bone fractures, we administered weekly oral alendronate, a drug widely used in the management of osteoporosis and other high bone turnover diseases, which blocks mevalonate and halts the prenylation process.

Results

All of the patient’s MKD clinical and laboratory abnormalities were resolved after starting alendronate treatment.

Conclusions

This observation appears enigmatic, since alendronate should reinforce the metabolic block characterizing MKD, but is crucial because of the ultimate improvement shown by this patient. The anti-inflammatory properties of bisphosphonates are a new question for debate among physicians across various specialties, and requires further biochemical and clinical investigation.

     

A lost opportunity for science: journals promote data sharing in metabolomics but do not enforce it

Introduction

Data sharing is being increasingly required by journals and has been heralded as a solution to the ‘replication crisis’.

Objectives

(i) Review data sharing policies of journals publishing the most metabolomics papers associated with open data and (ii) compare these journals’ policies to those that publish the most metabolomics papers.

Methods

A PubMed search was used to identify metabolomics papers. Metabolomics data repositories were manually searched for linked publications.

Results

Journals that support data sharing are not necessarily those with the most papers associated to open metabolomics data.

Conclusion

Further efforts are required to improve data sharing in metabolomics.

     

Pseudo current density maps of electrophysiological heart,nerve or brain function and their physical basis

Background

In recent years the visualization of biomagnetic measurement data by so-called pseudo current density maps or Hosaka-Cohen (HC) transformations became popular.

Methods

The physical basis of these intuitive maps is clarified by means of analytically solvable problems.

Results

Examples in magnetocardiography, magnetoencephalography and magnetoneurography demonstrate the usefulness of this method.

Conclusion

Hardware realizations of the HC-transformation and some similar transformations are discussed which could advantageously support cross-platform comparability of biomagnetic measurements.

     

Our local experience with the surgical treatment of ampullary cancer

Background

The aim of this study is to report the outcome after surgical treatment of 32 patients with ampullary cancers from 1990 to 1999.

Methods

Twenty-one of them underwent pancreaticoduodenectomy and 9 local excision of the ampullary lesion. The remaining 2 patients underwent palliative surgery.

Results

When the final histological diagnosis was compared with the preoperative histological finding on biopsy, accurate diagnosis was preoperatively established in 24 patients. The hospital morbidity was 18.8% as 9 complications occurred in 6 patients. Following local excision of the ampullary cancer, the survival rate at 3 and 5 years was 77.7% and 33.3% respectively. Among the patients that underwent Whipple's procedure, the 3-year survival rate was 76.2% and the 5-year survival rate 62%.

Conclusion

In this series, local resection was a safe option in patients with significant co-morbidity or small ampullary tumors less than 2 cm in size, and was associated with satisfactory long-term survival rates.

     

Ankle ligament reconstruction after wide resection of the osteosarcoma of the distal fibula: a case report

Background

Restoration of the lateral ankle after distal fibulectomy is a difficult reconstructive procedure. Many surgical techniques have been proposed. This report shows another fibular reconstructive option with promising outcome.

Case presentation

We report the case of a 30-year-old woman who presented with a solitary mass located in the lateral aspect of the ankle. The mass had grown rapidly for 2 months and caused increasing pain. Physical examination showed a 3.0 cm diameter tender, nonmobile hard mass in the lateral malleolus. Radiographs showed an osteolytic lesion involving the lateral cortex at the distal fibula. After incisional biopsy, pathologic examination found a well-differentiated intramedullary osteosarcoma. Neoadjuvant chemotherapy with doxorubicin was provided for 3 months prior to definitive surgical treatment. Magnetic resonance imaging showed persistent tumor in the biopsy site. After distal fibulectomy and wide resection, split tibialis posterior tendon transfer to the remaining peroneus brevis restored the stability of the ankle. The pain resolved within 3 months. The ankle was stable and no recurrence of the cancer was found at a 7 year follow-up.

Conclusion

Reconstruction following distal fibulectomy and surrounding soft tissue resection responds favorably to split tibialis posterior transfer to the remaining peroneus brevis suggesting that this technique can provide a good and functional outcome.

     

Untargeted metabolomics suffers from incomplete raw data processing

Introduction

Untargeted metabolomics is a powerful tool for biological discoveries. To analyze the complex raw data, significant advances in computational approaches have been made, yet it is not clear how exhaustive and reliable the data analysis results are.

Objectives

Assessment of the quality of raw data processing in untargeted metabolomics.

Methods

Five published untargeted metabolomics studies, were reanalyzed.

Results

Omissions of at least 50 relevant compounds from the original results as well as examples of representative mistakes were reported for each study.

Conclusion

Incomplete raw data processing shows unexplored potential of current and legacy data.

     

Metabolomic profiling of maternal hair suggests rapid development of intrahepatic cholestasis of pregnancy

Introduction

Intrahepatic cholestasis of pregnancy (ICP) is a common maternal liver disease; development can result in devastating consequences, including sudden fetal death and stillbirth. Currently, recognition of ICP only occurs following onset of clinical symptoms.

Objective

Investigate the maternal hair metabolome for predictive biomarkers of ICP.

Methods

The maternal hair metabolome (gestational age of sampling between 17 and 41 weeks) of 38 Chinese women with ICP and 46 pregnant controls was analysed using gas chromatography–mass spectrometry.

Results

Of 105 metabolites detected in hair, none were significantly associated with ICP.

Conclusion

Hair samples represent accumulative environmental exposure over time. Samples collected at the onset of ICP did not reveal any metabolic shifts, suggesting rapid development of the disease.

     

Quantitative analysis of tetrahydrofolate metabolites from <Emphasis Type="Italic">clostridium autoethanogenum</Emphasis>

Introduction

Quantification of tetrahydrofolates (THFs), important metabolites in the Wood–Ljungdahl pathway (WLP) of acetogens, is challenging given their sensitivity to oxygen.

Objective

To develop a simple anaerobic protocol to enable reliable THFs quantification from bioreactors.

Methods

Anaerobic cultures were mixed with anaerobic acetonitrile for extraction. Targeted LC–MS/MS was used for quantification.

Results

Tetrahydrofolates can only be quantified if sampled anaerobically. THF levels showed a strong correlation to acetyl-CoA, the end product of the WLP.

Conclusion

Our method is useful for relative quantification of THFs across different growth conditions. Absolute quantification of THFs requires the use of labelled standards.

     

A methodology for elucidating regulatory mechanisms leading to changes in lipid profiles

Introduction

It is difficult to elucidate the metabolic and regulatory factors causing lipidome perturbations.

Objectives

This work simplifies this process.

Methods

A method has been developed to query an online holistic lipid metabolic network (of 7923 metabolites) to extract the pathways that connect the input list of lipids.

Results

The output enables pathway visualisation and the querying of other databases to identify potential regulators. When used to a study a plasma lipidome dataset of polycystic ovary syndrome, 14 enzymes were identified, of which 3 are linked to ELAVL1—an mRNA stabiliser.

Conclusion

This method provides a simplified approach to identifying potential regulators causing lipid-profile perturbations.

     

KniMet: a pipeline for the processing of chromatography–mass spectrometry metabolomics data

Introduction

Data processing is one of the biggest problems in metabolomics, given the high number of samples analyzed and the need of multiple software packages for each step of the processing workflow.

Objectives

Merge in the same platform the steps required for metabolomics data processing.

Methods

KniMet is a workflow for the processing of mass spectrometry-metabolomics data based on the KNIME Analytics platform.

Results

The approach includes key steps to follow in metabolomics data processing: feature filtering, missing value imputation, normalization, batch correction and annotation.

Conclusion

KniMet provides the user with a local, modular and customizable workflow for the processing of both GC–MS and LC–MS open profiling data.

     

Progression of idiopathic thoracic or thoracolumbar scoliosis and pelvic obliquity in adolescent patients with and without limb length discrepancy

Βackground

Both limb length inequality and scoliosis are associated with pelvic obliquity.

Methods

This is an observational study of adolescents with growth potential presenting for evaluation of thoracic or thoracolumbar idiopathic scoliosis at an outpatient pediatric orthopedic clinic. Patients were evaluated for limb length discrepancy (LLD) (using bilateral femoral head height difference), pelvic obliquity (using bilateral iliac crest height difference and sacral takeoff angle), and scoliotic curve (using Cobb angle and rotation) on full spine standing radiographs. The same radiographic parameters were measured at a follow-up visit at least 2 years later.

Results

Seventy-three consecutive patients with a mean (SD) age of 13.3 (0.2) years at initial examination were included in the study. Scoliosis (major curve Cobb angle ≥?10°) was confirmed in all 73 patients, pelvic obliquity (iliac crest height difference >?1 cm or sacral takeoff angle >?5°) appeared in 23 (31.5%) patients with scoliosis, and LLD (>?1 cm femoral head height difference) was identified in 6 (8.2%) patients with scoliosis and pelvic obliquity. At a subsequent visit, a mean of 2.8 (range 2–5.8) years later, no significant change (p?>?0.05) in limb length inequality was observed but a statistically significant increase (p?<?0.05) in scoliotic and pelvic deformity parameters was found.

Conclusions

In adolescent patient population with thoracic or thoracolumbar scoliosis, the anisomelia remains stable with growth but both the scoliotic deformity and pelvic obliquity progress.

Trial registration

MGH no 2012-P-000774/1

     

Extraction of natural products from bark of <Emphasis Type="Italic">Betula pendula</Emphasis> using ionic liquids

Introduction

Aqueous–methanol mixtures have successfully been applied to extract a broad range of metabolites from plant tissue. However, a certain amount of material remains insoluble.

Objectives

To enlarge the metabolic compendium, two ionic liquids were selected to extract the methanol insoluble part of trunk from Betula pendula.

Methods

The extracted compounds were analyzed by LC/MS and GC/MS.

Results

The results show that 1-butyl-3-methylimidazolium acetate (IL-Ac) predominantly resulted in fatty acids, whereas 1-ethyl-3-methylimidazolium tosylate (IL-Tos) mostly yielded phenolic structures. Interestingly, bark yielded more ionic liquid soluble metabolites compared to interior wood.

Conclusion

From this one can conclude that the application of ionic liquids may expand the metabolic snapshot.

     

Metabolic response of porcine colon explants to in vitro infection by <Emphasis Type="Italic">Brachyspira hyodysenteriae</Emphasis>: a leap into disease pathophysiology

Introduction

Swine dysentery caused by Brachyspira hyodysenteriae is a production limiting disease in pig farming. Currently antimicrobial therapy is the only treatment and control method available.

Objective

The aim of this study was to characterize the metabolic response of porcine colon explants to infection by B. hyodysenteriae.

Methods

Porcine colon explants exposed to B. hyodysenteriae were analyzed for histopathological, metabolic and pro-inflammatory gene expression changes.

Results

Significant epithelial necrosis, increased levels of l-citrulline and IL-1α were observed on explants infected with B. hyodysenteriae.

Conclusions

The spirochete induces necrosis in vitro likely through an inflammatory process mediated by IL-1α and NO.

     

Phosphorus availability from bone char in a P-fixing soil influenced by root-mycorrhizae-biochar interactions

Aims

The objectives of this study were to evaluate (1) the fertilizer potential of bone char, (2) the effects of wood biochar on plant-available phosphorus (P), and (3) the role of root-mycorrhizae-biochar interactions in plant P acquisition from a P-fixing soil.

Methods

Incubation and pot experiments were conducted with a P-fixing soil and maize with or without root hairs and arbuscular mycorrhizae (AM) inoculation. Olsen-, resin-P and plant P accumulation were used to estimate P availability from bone char, co-pyrolyzed bone char-wood biochar, and separate bone char and wood biochar additions produced at 60, 350 and 750 °C, and Triple Superphosphate (TSP).

Results

Maize inoculated with AM showed similar P accumulation when fertilized with either 750 °C bone char or TSP. Pyrolyzing bone did not increase extractable P in soil in comparison to unpyrolyzed bone, apart from a 67 % increase in resin-extractable P after additions of bone char pyrolyzed at 350 °C. Despite greater Olsen-P extractability, co-pyrolysis of bone with wood reduced maize P uptake. Wood biochars reduced resin-P from bone char by 14–26 %, whereas oven-dried wood increased resin-P by 23 %.

Conclusions

Bone char is an effective P fertilizer, especially if root-AM interactions are simultaneously considered. Biochar influences plant access to soil P and requires careful management to improve P availability.

     

Lanthanum phosphate/chitosan scaffolds enhance cytocompatibility and osteogenic efficiency via the Wnt/β-catenin pathway

Background

Fabrication of porous scaffolds with great biocompatibility and osteoinductivity to promote bone defect healing has attracted extensive attention.

Methods

In a previous study, novel lanthanum phosphate (LaPO₄)/chitosan (CS) scaffolds were prepared by distributing 40- to 60-nm LaPO₄ nanoparticles throughout plate-like CS films.

Results

Interconnected three dimensional (3D) macropores within the scaffolds increased the scaffold osteoconductivity, thereby promoting cell adhesion and bone tissue in-growth. The LaPO₄/CS scaffolds showed no obvious toxicity and accelerated bone generation in a rat cranial defect model. Notably, the element La in the scaffolds was found to promote osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) through the Wnt/β-catenin signalling pathway and induced high expression of the osteogenesis-related genes alkaline phosphatase, osteocalcin and Collagen I (Col-I). Moreover, the LaPO₄/CS scaffolds enhanced bone regeneration and collagen fibre deposition in rat critical-sized calvarial defect sites.

Conclusion

The novel LaPO₄/CS scaffolds provide an admirable and promising platform for the repair of bone defects.