Proteogenomic Analysis of Human Uterine Cervical Cancer (UCC) Reveals Treatment-Resistant Subtypes of UCC

PURPOSE/OBJECTIVE(S)

Locally advanced uterine cervical cancer (UCC) is treated by radiotherapy with concurrent chemotherapy, but heterogenous treatment responses are frequently observed. To better optimize therapeutic options based on molecular signatures, we performed proteogenomic analysis of UCC.

MATERIALS/METHODS

UCC tissue and blood samples were collected from patients who underwent primary radiotherapy ± chemotherapy at the National Cancer Center (NCC) in Korea from July 2004 to March 2020. Most samples were obtained via biopsy. Genomic DNA for WES was isolated from frozen biopsy tumor tissues and peripheral blood buffy-coat of patients. Both global proteome and phosphoproteome were analyzed using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Whole exome sequencing, RNA sequencing, global proteomics and phosphoproteomics were performed using 253, 337, and 147 cervical cancer samples, respectively. Patient-derived xenograft were established using intratongue implantation using 2 primary cell lines from sub3 and sub5, and flow cytometric analysis was performed.

RESULTS

Fourteen significantly mutated genes (SMG) were found in our study cohort which include 5 newly identified SMGs. Mutation-phosphorylation analysis revealed association with apoptosis and actin cytoskeleton pathway. Proteogenomic analysis defined 6 molecular subtypes of UCC. Of those, 3 subtypes (i.e., Sub3, Sub5 and Sub6) were associated with treatment-resistant phenotypes. The cell-type deconvolution analysis suggested activated stroma with activation of cancer-associated fibroblast in Sub 3, while Sub5 showed low levels of activated stroma and high levels of myeloid immune cells. FACS analysis of UCC mouse models established from these 2 radio-resistant primary cell lines showed high component of PDGFRA+CAF infiltration in Sub 3, and high level of PVR+CD45+ immune cells mainly composed of polymorphonuclear myeloid-derived suppressor cells (PMN-MDSC) in Sub5. For Sub6, genes and/or protein signatures represented mucin-related processes (e.g., mucin glycosylation/sugar metabolism), which are linked to metastasis-associated Tn antigen production.

CONCLUSION

The proteogenomic analysis thus suggests potential targets for radiotherapy-resistant subtypes of UCC; secretory factors from activated stroma and cancer-associated fibroblast (Sub3); RHOA signaling, PVR, and PMN-MDSCs (Sub5), and keratin/chondroitin sulfate proteoglycan and Tn antigen production (Sub6). Our study shows the importance of proteogenomic analysis in unveiling the subtype specific molecular pathways of UCC that are beyond reach by genomic data alone. The validity of our molecular pathway and cellular signatures linking these pathways should be further validated through detailed functional experiments and in larger UCC cohorts.

PL01.3.A Radiomic features and DNA methylation attributes in primary CNS lymphoma

Background

Clinical and laboratory markers have been exploited to model risk in patients with primary CNS lymphoma (PCNSL), but the derived risk models do not fully explain the observed variation in outcome. Here we present an extended framework of phenotype-epigenotype correlations that reveal novel prognostic constellations and enable prioritizing epigenetic therapy.

Material and Methods

In this retrospective discovery and validation study, we leverage radiomic feature-driven analysis of medical images and supervised bioinformatic integration of DNA methylation profiles. We integrate both data modalities synergistically using machine learning-based prediction and cross-domain alignment. Ultimately, we validate the most relevant biological associations in tumor tissues and cell lines.

Results

We leverage a cohort of 191 patients across 9 sites in Austria and an external validation site in South Korea, and use T1-weighted contrast-enhanced magnetic resonance imaging to derive a radiomic risk score that consists of 20 mostly textural features. We determine the risk score as strong and independent predictive factor (multivariate HR=6.56), and confirm its prognostic value in an external validation cohort. Radiomic features align with DNA methylation sites in distinct, biologically meaningful ways, and radiomic risk is predictable from selected DNA methylation sites (AUC=0.78). Ultimately, gene-regulatory differences between radiomically-defined risk groups converge on bcl6 binding activity, which is posed as testable treatment strategy in a subset of patients.

Conclusion

The radiomic risk score is a robust and complementary predictor of survival and is reflected at the level of DNA methylation in PCNSL. Assessing risk and selecting epigenetic treatment based on imaging phenotypes represents a huge step forward, and the ability to define radiomic risk groups provides a concept on which to advance prognostic modeling and precision therapy for this aggressive brain cancer.

Detection and Assessment of α-Synuclein Oligomers in the Urine of Parkinson's Disease Patients

BACKGROUND

α-Synuclein (α-syn) is a major component of Lewy bodies, a pathologic marker of Parkinson's disease (PD) in post-mortem studies. The use of α-syn as a practical PD biomarker has been investigated by numerous researchers. However, reports of differences in α-syn levels in biofluids, such as cerebrospinal fluid, plasma, and saliva, between PD patients and controls are inconsistent. Recently, the measurement of α-syn oligomer levels has emerged as a novel approach to diagnose PD.

OBJECTIVE

Lysates and culture media from two different types of dopaminergic neuronal cells or urine samples from 11 non-PD and 21 PD patients were collected and analyzed.

METHODS

We developed and performed an enzyme-linked immuno-absorbent assay (ELISA) to detect various oligomeric α-syn using distinct pairs of antibodies.

RESULTS

We validated our ELISA using rotenone-induced alterations of α-syn levels in human dopaminergic neurons. Total urinary α-syn levels, measured using our ELISA method, showed no difference between PD and non-PD individuals, but a higher level of α-syn oligomer recognized by MJFR-14-6-5-2 in PD urine samples was observed. Levels of distinct oligomeric α-syn detected by ASyO5 were lower in PD urine samples. Three different α-syn ELISA results were analyzed with respect to the severity of PD, but only the correlation between total α-syn levels and PD index was significant.

CONCLUSION

Our findings suggest that detection of distinct oligomeric formations of α-syn and measurement of their levels in urine might be feasible for use in PD diagnostics.

Expression of transduced nucleolin promotes the clearance of accumulated α-synuclein in rodent cells and animal model

Alpha-synuclein (αSyn) is a major component of Lewy bodies, which are a known pathogenic marker of Parkinson's disease (PD). The dysfunction of protein degradation machinery causes αSyn accumulation. The reinforcement of αSyn degradation is a potential therapeutic target for PD because accumulated αSyn is responsible for the pathogenesis of PD. Nucleolin (NCL) is essential in the formation of the nucleolar structure. The function of NCL is correlated with oxidative stress-mediated cell death. A previous study demonstrated that NCL overexpression alleviated rotenone-induced neurotoxic effects, whereas knockdown of NCL had the opposite effect. These results suggest that NCL malfunction would exacerbate PD pathology. Thus, it was hypothesized that the introduction of ectopic NCL could rescue α-synucleinopathy in PD. This study investigated whether the ectopic expression of NCL facilitates αSyn clearance. Ectopic expression of NCL was accomplished via the transfection of green fluorescent protein (GFP) or GFP-NCL in mouse embryonic fibroblasts (MEF) or transduction of GFP or GFP-NCL using lentivirus in rat primary cortical neurons and mouse substantia nigra. NCL overexpression enhanced the clearance of accumulated or aggregated αSyn in MEFs and rat primary cortical neurons. The activity of the autophagy-lysosome pathway was enhanced by NCL expression. NCL transduction in the substantia nigra, which was co-injected with αSyn fibrils, rescued PD manifestation. The elevation of NCL levels may reflect a therapeutic strategy for α-synucleinopathy in PD.

Ciliogenesis is Not Directly Regulated by LRRK2 Kinase Activity in Neurons

Mutations in the Leucine-rich repeat kinase 2 (LRRK2) gene are the most prevalent cause of familial Parkinson’s disease (PD). The increase in LRRK2 kinase activity observed in the pathogenic G2019S mutation is important for PD development. Several studies have reported that increased LRRK2 kinase activity and treatment with LRRK2 kinase inhibitors decreased and increased ciliogenesis, respectively, in mouse embryonic fibroblasts (MEFs) and retinal pigment epithelium (RPE) cells. In contrast, treatment of SH-SY5Y dopaminergic neuronal cells with PD-causing chemicals increased ciliogenesis. Because these reports were somewhat contradictory, we tested the effect of LRRK2 kinase activity on ciliogenesis in neurons. In SH-SY5Y cells, LRRK2 inhibitor treatment slightly increased ciliogenesis, but serum starvation showed no increase. In rat primary neurons, LRRK2 inhibitor treatment repeatedly showed no significant change. Little difference was observed between primary cortical neurons prepared from wild-type (WT) and G2019S^+/- mice. However, a significant increase in ciliogenesis was observed in G2019S^+/- compared to WT human fibroblasts, and this pattern was maintained in neural stem cells (NSCs) differentiated from the induced pluripotent stem cells (iPSCs) prepared from the same WT/G2019S fibroblast pair. NSCs differentiated from G2019S and its gene-corrected WT counterpart iPSCs were also used to test ciliogenesis in an isogenic background. The results showed no significant difference between WT and G2019S regardless of kinase inhibitor treatment and B27-deprivation-mimicking serum starvation. These results suggest that LRRK2 kinase activity may be not a direct regulator of ciliogenesis and ciliogenesis varies depending upon the cell type or genetic background.

Analysis of α-synuclein levels related to LRRK2 kinase activity: from substantia nigra to urine of patients with Parkinson's disease

Research on Parkinson’s disease (PD) has been focused on the development of PD diagnostic tools as much as the development of PD therapeutics. Several genetic culprits of PD, including DJ-1, Leucine-rich repeat kinase 2 (LRRK2), and α-synuclein (α-syn), have been investigated as markers of PD in human biofluids. Unfortunately, the approaches to develop PD diagnostic tools are impractical, and there is a considerable demand for an appropriate marker of PD. The measurement of α-syn in biofluids has recently been made more accurate by examining monomers and aggregates separately using enzyme-linked immunosorbent assay (ELISA). Previously, we reported on the development of two types of sandwich ELISA for total α-syn and MJFR-14-6-4-2 antibody-specific α-syn fibrillar oligomers. The pathogenic LRRK2 G2019S mutation is related to increased α-syn secretion in the extracellular space. We tested our established ELISA using differentiated SH-SH5Y cells transfected with LRRK2 G2019S. The secretory levels of fibrillar oligomeric α-syn divided by total α-syn were significantly increased in LRRK2 G2019S-expressing cells. Additionally, substantia nigra lysates or concentrated urine from PD patients and non-PD subjects were analyzed. We observed ambiguous changes in the levels of total or fibrillar oligomeric α-syn and their ratio between PD and non-PD. Despite the insignificant increase in the relative levels of fibrillar oligomeric α-syn to total α-syn in PD, the duration of disease progression after diagnosis significantly corresponded to the relative levels of fibrillar oligomeric α-syn to total α-syn in the urine. These results might provide greater understanding for the next stage of development of α-syn ELISAs.

Subnanosecond phase transition dynamics in laser-shocked iron

Iron is one of the most studied chemical elements due to its sociotechnological and planetary importance; hence, understanding its structural transition dynamics is of vital interest. By combining a short pulse optical laser and an ultrashort free electron laser pulse, we have observed the subnanosecond structural dynamics of iron from high-quality x-ray diffraction data measured at 50-ps intervals up to 2500 ps. We unequivocally identify a three-wave structure during the initial compression and a two-wave structure during the decaying shock, involving all of the known structural types of iron (α-, γ-, and ε-phase). In the final stage, negative lattice pressures are generated by the propagation of rarefaction waves, leading to the formation of expanded phases and the recovery of γ-phase. Our observations demonstrate the unique capability of measuring the atomistic evolution during the entire lattice compression and release processes at unprecedented time and strain rate.

Does patient-reported perception of pain differ based on surgical approach in total hip arthroplasty?

Aims

Whether patient-reported pain differs among surgical approaches in total hip arthroplasty (THA) remains unclear. This study’s purposes were to determine differences in pain based on surgical approach (direct anterior (DA) vs posterolateral (PL)) and PL approach incision length.

Patients and Methods

This was a retrospective investigation from two centres and seven surgeons (three DA, three PL, one both) of primary THAs. PL patients were categorized for incision length (6 cm to 8 cm, 8 cm to 12 cm, 12 cm to 15 cm). All patients had cementless femoral and acetabular fixation, at least one year’s follow-up, and well-fixed components. Patients completed a pain-drawing questionnaire identifying the location and intensity of pain on an anatomical diagram. Power analysis indicated 800 patients in each cohort for adequate power to detect a 4% difference in pain (alpha = 0.05, beta = 0.80).

Results

A total of 1848 patients (982 DA, 866 PL) were included. PL patients were younger (59.4 years, sd 12.9 vs 62.7 years, sd 9.7; p < 0.001) and had shorter follow-up (3.3 years, sd 1.3 vs 3.7 years, sd 1.3; p < 0.001). DA patients reported decreased moderate to severe trochanteric (14% vs 21%; p < 0.001) and groin pain (19% vs 24%; p = 0.004) than PL patients. There were no differences in anterior, lateral, or posterior thigh, back, or buttock pain between cohorts (p = 0.05 to 0.7). PL approach incision length did not impact the incidence or severity of pain (p = 0.3 to 0.7).

Conclusion

A significant proportion of patients perceive persistent pain following THA regardless of approach. DA patients reported less trochanteric and groin pain versus PL patients. PL incision length did not influence the incidence or severity of patient-reported pain. Cite this article: Bone Joint J 2019;101-B(6 Supple B):31–36.

Is a modular dual mobility acetabulum a viable option for the young, active total hip arthroplasty patient?

AIMS

Modular dual mobility (DM) prostheses in which a cobalt-chromium liner is inserted into a titanium acetabular shell ( vs a monoblock acetabular component) have the advantage of allowing supplementary screw fixation, but the potential for corrosion between the liner and acetabulum has raised concerns. While DM prostheses have shown improved stability in patients deemed 'high-risk' for dislocation undergoing total hip arthroplasty (THA), their performance in young, active patients has not been reported. This study's purpose was to assess clinical outcomes, metal ion levels, and periprosthetic femoral bone mineral density (BMD) in young, active patients receiving a modular DM acetabulum and recently introduced titanium, proximally coated, tapered femoral stem design.

PATIENTS AND METHODS

This was a prospective study of patients between 18 and 65 years of age, with a body mass index (BMI) < 35 kg/m² and University of California at Los Angeles (UCLA) activity score > 6, who received a modular cobalt-chromium acetabular liner, highly crosslinked polyethylene mobile bearing, and cementless titanium femoral stem for their primary THA. Patients with a history of renal disease and metal hardware elsewhere in the body were excluded. A total of 43 patients (30 male, 13 female; mean age 52.6 years (sd 6.5)) were enrolled. All patients had a minimum of two years' clinical follow-up. Patient-reported outcome measures, whole blood metal ion levels (ug/l), and periprosthetic femoral BMD were measured at baseline, as well as at one and two years postoperatively. Power analysis indicated 40 patients necessary to demonstrate a five-fold increase in cobalt levels from baseline (alpha = 0.05, beta = 0.80). A mixed model with repeated measures was used for statistical analysis.

RESULTS

Mean Harris Hip Scores improved from 54.1 (sd 20.5) to 91.2 (sd 10.8) at two years postoperatively (p < 0.001). All patients had radiologically well-fixed components, no patients experienced any instability, and no patients required any further intervention. Mean cobalt levels increased from 0.065 ug/l (sd 0.03) preoperatively to 0.30 ug/l (sd 0.51) at one year postoperatively (p = 0.01) but decreased at two years postoperatively to 0.16 ug/l (sd 0.23; p = 0.2). Four patients (9.3%) had a cobalt level outside the reference range (0.03 ug/l to 0.29 ug/l) at two years postoperatively, with values from 0.32 ug/l to 0.94 ug/l. The mean femoral BMD ratio was maintained in Gruen zones 2 to 7 at both one and two years postoperatively using this stem design. At two years postoperatively, mean BMD in the medial calcar was 101.5% of the baseline value.

CONCLUSION

Use of a modular DM prosthesis and cementless, tapered femoral stem has shown encouraging results in young, active patients undergoing primary THA. Elevation in mean cobalt levels and the presence of four patients outside the reference range at two years postoperatively demonstrates the necessity of continued surveillance in this cohort. Cite this article: Bone Joint J 2019;101-B:365-371.

Rab GTPases as Physiological Substrates of LRRK2 Kinase

LRRK2 (Leucine-Rich Repeat Kinase 2) is a gene whose specific mutations cause Parkinson's disease (PD), the most common neurodegenerative movement disorder. LRRK2 harbors GTPase and kinase activities, two enzyme activities that play critical roles in the regulation of cellular signal transduction. Among the several LRRK2 pathogenic mutations, the most prevalent G2019S mutation increases its kinase activity when compared with the wild-type (WT), suggesting that LRRK2 kinase substrates are potential culprits of PD pathogenesis. Although there were several studies to identify LRRK2 kinase substrates, most of them mainly employed in vitro kinase assays. Therefore, it remains uncertain whether the identified substrates were real physiological substrates. However, efforts to determine physiological LRRK2 kinase substrates have recently identified several members of the Rab GTPase family as physiological LRRK2 kinase substrates. A conserved threonine or serine in the switch II domain of certain Rab GTPase family members (Rab3A/B/C/D, Rab5A/B, Rab8A/B, Rab10, Rab12, Rab29, Rab35 and Rab43) has been pinpointed to be phosphorylated by LRRK2 in cells using sophisticated phosphoproteomics technology in combination with LRRK2-specific kinase inhibitors. The Rab GTPases regulate vesicle trafficking, suggesting that LRRK2 may be a regulator of such vesicle trafficking, confirming previously suggested LRRK2 functions. However, how the consequence of the LRRK2-mediated Rab phosphorylation is related to PD pathogenesis is not clear. This review briefly summarizes the recent results about LRRK2-mediated Rab phosphorylation studies.

LRRK2 impairs autophagy by mediating phosphorylation of leucyl-tRNA synthetase

Leucine-rich repeat kinase 2 (LRRK2) is a causal gene of Parkinson disease. G2019S pathogenic mutation increases its kinase activity. LRRK2 regulates various phenotypes including autophagy, neurite outgrowth, and vesicle trafficking. Leucyl-tRNA synthetase (LRS) attaches leucine to tRNA^Leu and activates mTORC1. Down-regulation of LRS induces autophagy. We investigated the relationship between LRRK2 and LRS in regulating autophagy and observed interaction between endogenous LRRK2 and LRS proteins and LRS phosphorylation by LRRK2. Mutation studies implicated that T293 in the LRS editing domain was a putative phosphorylation site. Phospho-Thr in LRS was increased in cells overexpressing G2019S and dopaminergic neurons differentiated from induced pluripotent stem (iPS) cells of a G2019S carrier. It was decreased by treatment with an LRRK2 kinase inhibitor (GSK2578215A). Phosphomimetic T293D displayed lower leucine bindings than wild type (WT), suggesting its defective editing function. Cellular expression of T293D increased expression of GRP78/BiP, LC3B-II, and p62 proteins and number of LC3 puncta. Increase of GRP78 and phosphorylated LRS was diminished by treatment with GSK2578215A. Levels of LC3B, GRP78/BiP, p62, and α-synuclein proteins were also increased in G2019S transgenic (TG) mice. These data suggest that LRRK2-mediated LRS phosphorylation impairs autophagy by increasing protein misfolding and endoplasmic reticulum stress mediated by LRS editing defect. SIGNIFICANCE OF THE STUDY: Leucine-rich repeat kinase 2 (LRRK2) is the most common genetic cause of Parkinson disease (PD), and the most prevalent pathogenic mutation, G2019S, increases its kinase activity. In this study, we elucidated that leucyl-tRNA synthetase (LRS) was an LRRK2 kinase substrate and identified T293 as an LRRK2 phosphorylation site. LRRK2-meidated LRS phosphorylation or G2019S can lead to impairment of LRS editing, increased ER stress, and accumulation of autophagy markers. These results demonstrate that LRRK2 kinase activity can facilitate accumulation of misfolded protein, suggesting that LRRK2 kinase might be a potential PD therapeutic target along with previous studies.

Improving Population-Wide Collection of Stage at Diagnosis for Childhood Cancer: International Collaboration and Progress

Background: There are huge international disparities in childhood cancer survival. The International Agency for Research on Cancer's Global Initiative for Cancer Registry Development has improved cancer registry coverage of the world's population, particularly in low- and middle-income countries (LMICs). However, for virtually all registries around the world, the challenge remains of collecting comparable and population-wide information on stage at diagnosis. This information is essential to understand and address disparities in outcomes. In response to this, a UICC-endorsed set of consensus guidelines for assigning stage for 16 of the most common types of childhood cancer was recently developed (the Toronto Guidelines), for use by population registries in both high and LMICs. Aim: To trial the Toronto Guidelines on a population-basis, and develop a structured protocol, suitable for global implementation, for collecting the required data elements and assigning cancer stage at diagnosis for childhood cancer. Methods: Using an innovative approach, data items as defined in the Toronto Guidelines were gathered from the medical record and entered electronically. Stage at diagnosis was assigned automatically using computer algorithms, thus reducing errors and maximizing consistency. Data collection and assignment of stage were incorporated into an online platform that was then trialed in the national childhood cancer registries of Australia and New Zealand for cases diagnosed between 2006 and 2014. Results: Stage at diagnosis was successfully assigned for 94% of all eligible patients (n=1662) across both countries. In contrast, stage as recorded by the treating clinician was located in the medical record for only 39% of cases in Australia. Conclusion: Practical implementation of the Toronto Guidelines has been highly successful to date and further testing is planned in LMICs. This approach has the potential to improve global epidemiologic monitoring of childhood cancer and lead to better understanding of the reasons underlying disparities in outcome.

Increase in anti-apoptotic molecules, nucleolin, and heat shock protein 70, against upregulated LRRK2 kinase activity

Leucine-rich repeat kinase 2 (LRRK2) is involved in Parkinson’s disease (PD) pathology. A previous study showed that rotenone treatment induced apoptosis, mitochondrial damage, and nucleolar disruption via up-regulated LRRK2 kinase activity, and these effects were rescued by an LRRK2 kinase inhibitor. Heat-shock protein 70 (Hsp70) is an anti-oxidative stress chaperone, and overexpression of Hsp70 enhanced tolerance to rotenone. Nucleolin (NCL) is a component of the nucleolus; overexpression of NCL reduced cellular vulnerability to rotenone. Thus, we hypothesized that rotenone-induced LRRK2 activity would promote changes in neuronal Hsp70 and NCL expressions. Moreover, LRRK2 G2019S, the most prevalent LRRK2 pathogenic mutant with increased kinase activity, could induce changes in Hsp70 and NCL expression. Rotenone treatment of differentiated SH-SY5Y (dSY5Y) cells increased LRKK2 levels and kinase activity, including phospho-S935-LRRK2, phospho-S1292-LRRK2, and the phospho-moesin/moesin ratio, in a dose-dependent manner. Neuronal toxicity and the elevation of cleaved poly (ADP-ribose) polymerase, NCL, and Hsp70 were increased by rotenone. To validate the induction of NCL and Hsp70 expression in response to rotenone, cycloheximide (CHX), a protein synthesis blocker, was administered with rotenone. Post-rotenone increased NCL and Hsp70 expression was repressed by CHX; whereas, rotenone-induced kinase activity and apoptotic toxicity remained unchanged. Transient expression of G2019S in dSY5Y increased the NCL and Hsp70 levels, while administration of a kinase inhibitor diminished these changes. Similar results were observed in rat primary neurons after rotenone treatment or G2019S transfection. Brains from G2019S-transgenic mice also showed increased NCL and Hsp70 levels. Accordingly, LRRK2 kinase inhibition might prevent oxidative stress-mediated PD progression.

Abbreviations: 6-OHDA: 6-hydroxydopamine; CHX: cycloheximide; dSY5Y: differentiated SH-SY5Y; g2019S tg: g2019S transgenic mouse; GSK/A-KI: GSK2578215A kinase inhibitor; HSP70: heat shock protein 70; LDH: lactose dehydrogenase; LRRK2: leucine rich-repeat kinase 2; MPTP: 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine; myc-GS LRRK2: myc-tagged g2019S LRRK2; NCL: nucleolin; PARP: poly(ADP-ribose) polymerase; PD: Parkinson’s disease; PINK1: PTEN-induced putative kinase 1; pmoesin: phosphorylated moesin at t558; ROS: reactive oxygen species

Characterization of Parkinson's disease-related pathogenic TMEM230 mutants

Parkinson's disease (PD) is the second most common neurodegenerative disease. Although most PD cases are sporadic, 5-10% of them are hereditary and several pathogenic mutations in related genes have been identified. Mutations in TMEM230 were recently identified as a cause of autosomal dominant PD. However, the basic properties of the mutant proteins are not yet known. We examined stability and neurotoxicity, important characteristics of PD pathogenesis-related proteins, of WT TMEM230 and two pathogenic mutants, R78L and PG5ext, in a dopaminergic neuronal cell line. Our study showed that amount of protein expressed in the same vector backbone was R78L > WT > PG5ext. The stabilities of the mutant proteins were similar to each other, but lower than that of the WT. In addition, overexpression of mutants and WT TMEM230 caused similar levels of neurotoxicity upon MPP+ treatment when compared to the cells transfected with an empty vector. Because the proteins encoded by two PD-causing genes, TMEM230 and LRRK2, function in vesicle trafficking, we tested whether they interact. LRRK2 neither interacts with, nor phosphorylates TMEM230. We also investigated the levels of several Rab proteins (Rab1A, 5, 7, 8A and 11) involved in vesicle trafficking after TMEM230 overexpression. However, there was no clear difference of any Rab proteins among cells transfected with an empty vector, TMEM230 WT and mutants-expressing cells, suggesting that TMEM230 does not directly regulate these Rab proteins. Thus, these TMEM230 PG5ext and R78L mutant proteins are not distinctly different from the WT proteins except for their stability. Abbreviations: LRRK2: Leucine-rich repeat kinase 2; PD: Parkinson's disease; AD: Alzheimer's disease; RT-PCR: reverse transcription-polymerase chain reaction; SDS-PAGE: sodium dodecyl sulfate-polyacrylamide gel electrophoresis; FACS: fluorescence-activated cell sorting; PBS: phosphate buffered saline; FBS: fetal bovine serum; PI: propidium iodide.

Mobile pump deep vein thrombosis prophylaxis: just say no to drugs

AIMS

The purpose of this article was to review the current literature pertaining to the use of mobile compression devices (MCDs) for venous thromboembolism (VTE) following total joint arthroplasty (TJA), and to discuss the results of data from our institution.

PATIENTS AND METHODS

Previous studies have illustrated higher rates of post-operative wound complications, re-operation and re-admission with the use of more aggressive anticoagulation regimens, such as warfarin and factor Xa inhibitors. This highlights the importance of the safety, as well as efficacy, of the chemoprophylactic regimen.

RESULTS

Studies have shown a symptomatic VTE rate of 0.92% with use of MCDs for prophylaxis, which is comparable with rates seen with more aggressive anticoagulation protocols. A prior prospective study found that use of a pre-operative risk stratification protocol based on personal history of deep vein thrombosis, family history of VTE, active cancer, or a hypercoaguable state allowed for the avoidance of aggressive prophylactic anticoagulation in over 70% of patients while maintaining a low incidence of symptomatic VTE.

CONCLUSION

Further investigation is needed into the role of aspirin in VTE prophylaxis as well as the efficacy of MCDs as stand-alone prophylactic treatment. Cite this article: Bone Joint J 2017;99-B(1 Supple A):8-13.

Obesity in total hip arthroplasty

Aims

The purpose of our study is to summarise the current scientific findings regarding the impact of obesity on total hip arthroplasty (THA); specifically the influence of obesity on the timing of THA, incidence of complications, and effect on clinical and functional outcomes.

Materials and Methods

We performed a systematic review that was compliant with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines to identify prospective studies from the PubMed/Medline, Embase, and Cochrane Library databases that evaluated primary THA in obese (body mass index (BMI) ≥ 30 kg/m2) patients.

Results

There were 17 articles included in the review, which encompassed 13 722 THA patients. Analysis of the included studies showed that, when compared with non-obese patients, obesity was associated with younger age at time of primary THA, and an increased incidence of complications (up to four-fold). Results were mixed on the influence of obesity on the outcomes of primary THA, with three studies showing a detrimental effect on outcomes of a BMI ≥ 30 kg/m2, while eight studies showed no effect.

Conclusion

Obesity is associated with significantly younger age at time of primary THA and obese patients are likely to experience a higher rate of peri-operative complications. More investigation is needed into the effect of obesity on clinical outcomes, as the current literature is mixed. Cite this article: Bone Joint J 2017;99-B(1 Supple A):31–6.

Four-corner arthrodesis using two headless compression screws

We present the outcome of four-corner wrist arthrodesis using two headless compression screws for fixation. The study group consisted of 27 patients who underwent arthrodesis from 1998 through 2007. Data on demographic parameters, diagnosis, range of motion, pain and complications were collected from the medical files. A total of 77 series of anteroposterior, oblique, and lateral x-rays were reviewed by three independent interpreters ; consensus of at least two was required for the bones to be considered fused. Fusion was achieved in 24/27 wrists. Overall, inter-observer agreement in identifying radiographic bony fusion was fair (κ = 0.41). At the critical timing, 86 (SD 68) days postoperatively, when the decision regarding -fusion was made, inter-observer agreement was poor (κ = 0.07). Our rates of fusion are consistent with -reports in the literature. Radiographs performed at 3 months after four-corner arthrodesis are not -reliable for the diagnosis of fusion.

Tranexamic acid

Aims

This study investigated whether the use of tranexamic acid (TXA) decreased blood loss and transfusion related cost following surface replacement arthroplasty (SRA).

Methods

A retrospective review of patients treated with TXA during a SRA, who did not receive autologous blood (TXA group) was performed. Two comparison groups were established; the first group comprised of patients who donated their own blood pre-operatively (auto group) and the second of patients who did not donate blood pre-operatively (control). Outcomes included transfusions, post-operative haemoglobin (Hgb), complications, and length of post-operative stay.

Results

Between 2009 and 2013, 150 patients undergoing SRA were identified for inclusion: 51 in the auto, 49 in the control, and 50 in the TXA group. There were no differences in the pre-operative Hgb concentrations between groups. The mean post-operative Hgb was 11.3 g/dL (9.1 to 13.6) in the auto and TXA groups, and 10.6 g/dL (8.1 to 12.1)in the control group (p = 0.001). Accounting for cost of transfusions, administration of TXA, and length of stay, the cost per patient was $1731, $339, and $185 for the auto, control and TXA groups, respectively.

Discussion

TXA use demonstrated higher post-operative Hgb concentrations when compared with controls and decreased peri-operative costs. Take home message: Tranexamic acid safely limits allogeneic transfusion, maintains post-operative haemoglobin, and decreases direct and indirect transfusion related costs in surface replacement arthroplasty. Cite this article: Bone Joint J 2016;98-B:173–8.

Patient dissatisfaction following total knee replacement

A national, multi-centre study was designed in which a questionnaire quantifying the degree of patient satisfaction and residual symptoms in patients following total knee replacement (TKR) was administered by an independent, blinded third party survey centre. A total of 90% of patients reported satisfaction with the overall functioning of their knee, but 66% felt their knee to be ‘normal’, with the reported incidence of residual symptoms and functional problems ranging from 33% to 54%. Female patients and patients from low-income households had increased odds of reporting dissatisfaction. Neither the use of contemporary implant designs (gender-specific, high-flex, rotating platform) or custom cutting guides (CCG) with a neutral mechanical axis target improved patient-perceived outcomes. However, use of a CCG to perform a so-called kinematically aligned TKR showed a trend towards more patients reporting their knee to feel ‘normal’ when compared with a so called mechanically aligned TKR

This data shows a degree of dissatisfaction and residual symptoms following TKR, and that several recent modifications in implant design and surgical technique have not improved the current situation.

Cite this article: Bone Joint J 2014;96-B(11 Suppl A):96–100.

Reducing blood loss after total knee replacement

Blood loss during total knee replacement (TKR) remains a significant concern. In this study, 114 patients underwent TKR, and were divided into two groups based on whether they received a new generation fibrin sealant intra-operatively, or a local infiltration containing adrenaline. Groups were then compared for mean calculated total blood volume (TBV) loss, transfusion rates, and knee range of movement. Mean TBV loss was similar between groups: fibrin sealant mean was 705 ml (281 to 1744), local adrenaline mean was 712 ml (261 to 2308) (p = 0.929). Overall, significantly fewer units of blood were transfused in the fibrin sealant group (seven units) compared with the local adrenaline group (15 units) (p = 0.0479). Per patient transfused, significantly fewer units of blood were transfused in the fibrin sealant group (1.0 units) compared with the local adrenaline group (1.67 units) (p = 0.027), suggesting that the fibrin sealant may reduce the need for multiple unit transfusions. Knee range of movement was similar between groups. From our results, it appears that application of this newer fibrin sealant results in blood loss and transfusion rates that are low and similar to previously applied fibrin sealants.

Cite this article: Bone Joint J 2013;95-B, Supple A:135–9.

A rare case of a bisphosphonate-induced peri-prosthetic femoral fracture

An 81-year-old woman presented with a fracture in the left femur. She had well-fixed bilateral hip replacements and had received long-term bisphosphonate treatment. Prolonged bisphosphonate use has been recently linked with atypical subtrochanteric and diaphyseal femoral fractures. While the current definition of an atypical fracture of the femur excludes peri-prosthetic fractures, this case suggests that they do occur and should be considered in patients with severe osteopenia. Union of the fracture followed cessation of bisphosphonates and treatment with teriparatide. Thus, this case calls into question whether prophylactic intramedullary nailing is sufficient alone to treat early or completed atypical femoral fractures.

Proximal row carpectomy vs four corner fusion for scapholunate (Slac) or scaphoid nonunion advanced collapse (Snac) wrists: a systematic review of outcomes

Proximal row carpectomy (PRC) and scaphoid excision with four-corner fusion (4CF) are common motion-preserving, salvage procedures for the treatment of wrists with scaphoid nonunion (SNAC) or scapholunate advanced collapse (SLAC). A systematic review was undertaken to clarify controversies regarding which of these procedures has the better outcome. We collated 52 articles that examine outcomes for SNAC or SLAC patients undergoing PRC or 4CF. Although the lack of unbiased trials must be acknowledged, this systematic review confirms that both procedures give improvements in pain and subjective outcome measures for patients with symptomatic and appropriately staged SLAC or SNAC wrists. PRC may provide better postoperative range of movement and lacks the potential complications specific to 4CF (nonunion, hardware issues and dorsal impingement). However, the risk of subsequent osteoarthritis is significantly higher in PRC patients despite the majority being asymptomatic at the time of review. Grip strength, pain relief and subjective outcomes are similar in both treatment groups.

Observations on haemoglobin types in three breeds of Omani goats

Haemoglobin (Hb) types were studied in three breeds of Omani goats, Batinah (n = 22), Jebel Akhdar (n = 27) and Dhofari (n = 85). Type A was the only adult Hb observed in adult Batinah and Jebel Akhdar goats. In contrast, only 34% of the Dhofari goats were homozygous for Hb A, while 66% were heterozygous for Hb A and Hb B. Dhofari goats with type AB could further be differentiated into those with approximately 67% type A and 33% type B and those with approximately 33% type A and 67% type B. None of the goats was homozygous for type B. Seventeen kids observed from birth exhibited different levels of fetal Hb, dependent upon whether they developed the adult phenotype AA or AB. Kids that became homozygous for type A were born with approximately 90% Hb F and 10% Hb A. In contrast, goats that developed the heterozygous AB phenotype were born with only 30-60% Hb F, the remaining Hb being types A and B. These findings are not in accordance with previous reports that kids are born without any adult Hb. Hb F was no longer detectable in any of the three breeds of goats at 49 days of age. There was no evidence of Hb C, the pre-adult form of Hb.

Role of corticosterone in ethyl carbamate-induced immunosuppression in female BALB/c mice

We have recently demonstrated that the antibody response to the T-cell-dependent antigen, sheep red blood cells (SRBCs), was suppressed by ethyl carbamate in female BALB/c mice. At the same doses, ethyl carbamate decreased in the numbers of splenic macrophages, B cells, total T cells, CD4(+) T cells and CD8(+) T cells. In addition, the serum level of corticosterone was increased dose-dependently. To investigate the possible role of corticosterone in ethyl carbamate-induced immunosuppression, the antibody response to SRBCs and the subpopulation changes of splenocytes and thymocytes were determined in naive, sham-operated and adrenalectomized (ADX) female BALB/c mice. When the mice were treated intraperitoneally with 400 mg/kg ethyl carbamate, the antibody response was significantly suppressed by ethyl carbamate in naive and sham-operated mice in accompanying the decrease in spleen and thymus weights and/or the increase in the level of serum corticosterone. Meanwhile, the antibody response was not suppressed by ethyl carbamate in the ADX mice. The splenic numbers of total cells, macrophages, B and T cells, and CD4(+) cells were decreased by ethyl carbamate in naive and sham-operated mice. Meanwhile, each cell number was comparable with control in the ADX mice. The flow cytometric analyses on thymocytes did not show obvious differences as seen in the spleen. Finally, when the ADX mice were treated intraperitoneally with 25 mg/kg corticosterone, the antibody response was significantly suppressed. Taken together, our present results suggested that corticosterone might be, at least partially, responsible for ethyl carbamate-induced immunosuppression in female BALB/c mice.

Long-term effects of nitrous oxide anaesthesia on laboratory and clinical parameters in elderly Omani patients: a randomized double-blind study

AIMS

This study examined the long-term effects of nitrous oxide anaesthesia on serum levels of cobalamin and folate, red cell folate levels and haematological parameters, and neurological status in elderly Omani patients.

METHODS

Sixty-nine consecutive patients undergoing ophthalmic surgery were randomly and double-blind assigned to nitrous oxide or propofol anaesthesia. They met the following entry criteria: age 55 years or above, no major organ failure, no clinical signs or symptoms of cobalamin or folate deficiency, mean cell volume (MCV) </= 96 fl, haematocrit (Hct) higher than 0.3 and no cobalamin and/or folate substitution therapy during the preceding months. Serum levels of cobalamin and folate, red cell folate levels, and haematological parameters were measured prior to anaesthesia and 3-5 weeks later. At that time, the patients also underwent thorough neurological examination.

RESULTS

Data of 51 patients were complete and considered for analysis. In both nitrous oxide and propofol group, the range of exposure time was comparable (+/-1 h). In the nitrous oxide group, a slight but significant decrease in haemoglobin, Hct, and red blood cell count (RBC) (P < 0.001) was observed, whereas there was a mild increase in mean cell haemoglobin (MCH) and mean cell volume (P < 0.05). In addition, there was a significant decrease in serum folate levels (P < 0.05). Hct and RBC decreased slightly in the propofol group (P < 0. 05), whereas there was a small increase in MCH. There was no difference between the two anaesthetics with regard to serum cobalamin and red cell folate levels, but there was a significant decrease in serum folate levels in the nitrous oxide group compared to those in the propofol group. Three patients with pre-existing low red cell folate levels, who were randomized to nitrous oxide anaesthesia, developed clinical symptoms of folate deficiency.

CONCLUSION

This study showed that short-term (40-80 min) nitrous oxide anaesthesia did not affect cobalamin levels but reduced serum folate levels in this elderly population. Although this reduction was clinically irrelevant, some patients with pre-existing asymptomatic folate deficiency developed nitrous oxide-induced folate deficiency.

New dopamine receptor, D2(Longer), with unique TG splice site, in human brain

Brain dopamine receptor agonists alleviate the signs of Parkinson's disease, while dopamine receptor antagonists alleviate hallucinations and delusions in psychosis. The dopamine type 2 receptor (or D2) is blocked by antipsychotic drugs, including even the "atypical" drugs such as clozapine or remoxipride, in direct relation to their clinical potencies. Compared to the long form of the D2 receptor (D2(Long)), the short form (D2(Short)) may be three times more sensitive to benzamide antipsychotic drugs. Hence, it is essential to identify additional variants of dopamine receptors for which more selective antipsychotic drugs can be found. Although no family linkage has been found between the D2 receptor and schizophrenia, there can be brain region abnormalities in the RNA transcript expression of dopamine receptors. Therefore, in order to identify variant dopamine D2 receptors, we searched for mutations in the RNA transcripts for the dopamine D2 receptor in the striatum of post-mortem brains from individuals who died with psychosis, including schizophrenia. A new splice variant of the D2 receptor, D2(Longer), with a unique TG splice site, was found in one control brain and in two psychotic brains.

The human serotonin-7 receptor pseudogene: variation and chromosome location

We report a variation of the pseudogene for the serotonin-7 receptor in human DNA. Human genomic DNA was amplified, using the polymerase chain reaction method and degenerate oligonucleotide primers for serotonin receptor-like genes. A novel gene DNA sequence of 1325 bp was found. Based on nucleotides, this gene is 88% identical to the serotonin-7 receptor coding sequence. Compared with the previously known serotonin-7 receptor pseudogene, this pseudogene has 1 nucleotide deletion and 4 nucleotide mutations. The gene is located on human chromosome 12 at 12p12.3-p13.2.

A human serotonin-7 receptor pseudogene

Although the serotonin-7 receptor was cloned several years ago, its localization in brain tissues remains confusing because of the existence of a related expressed pseudogene, the sequence of which has not hitherto been reported. During the course of searching for related receptor genes, we also searched for this pseudogene to determine its sequence. Human genomic DNA was screened for dopamine and serotonin receptor-like genes, using the polymerase chain reaction method and degenerate oligonucleotide primers based on the similar sequences in the transmembrane-6 and -7 regions of the serotonin-5A, the serotonin-7, and the dopamine D2, D3 and D4 receptors. This resulted in one of the clones having a 115 bp fragment, of which 89% of the bases were identical to the transmembrane-6 and -7 regions of the serotonin-7 receptor sequence. The fragment was radiolabelled and used to screen a human fetal brain cDNA library. A novel cDNA clone of 1326 bp was isolated. Based on the nucleotide sequence, 88% of the bases in this sequence of the pseudogene are identical to the human serotonin-7 receptor coding sequence. However, compared to the serotonin-7 receptor DNA sequence, the pseudogene sequence has nucleotide deletions and insertions, resulting in frame-shifts and stop codons. It was concluded that this sequence represented a pseudogene related to the serotonin-7 receptor gene.

Dopamine and serotonin receptors: amino acid sequences, and clinical role in neuroleptic parkinsonism

This review summarizes the amino acid sequences of the human dopamine and serotonin receptors and their human variants. The review also examines the receptor basis of the atypical antipsychotic drugs that elicit less parkinsonism than the typical antipsychotics. Because the dissociation constant of a drug varies with the radioligand, the dissociation constants of many neuroleptics are here summarized for the dopamine D2-, D4- and serotonin S2A-receptors using different radioligands. Radioligands of low solubility in the membrane (having low tissue/buffer partition) result in lower values for the neuroleptic dissociation constants, compared to radioligands of high membrane solubility. Such studies yield the intrinsic K value for a neuroleptic in the absence of a competing ligand. Clozapine, for example, has an intrinsic K value of 1.6 nM at the D4-receptor, in agreement with the value of 1.6 nM when directly measured with [3H]clozapine at D4. However, because clozapine competes with endogenous dopamine, the in vivo clozapine concentration to occupy 75% of the dopamine D4-receptors is derived to be approximately 13 nM. This agrees with the value of 12 to 20 nM in the plasma water (or spinal fluid) observed in treated patients. Moreover, in L-DOPA psychosis (in Parkinson's disease), the clozapine concentration for 75% blockade of D4 is predicted to be approximately 3 nM. This agrees with the value of approximately 1.2 nM observed by Meltzer et al. in plasma water (Neuropsychopharmacology, 12, 39-45 (1995)). This analysis supports the concept and practical value of the intrinsic K values. Some atypical neuroleptics (remoxipride, clozapine, perlapine, seroquel and melperone) have high intrinsic K values (ranging from 30 to 88 nM) at the D2-receptor, making them displaceable by high levels of endogenous dopamine in the caudate/putamen. In contrast, however, typical neuroleptics (i.e., those that typically cause parkinsonism) have intrinsic K values of 0.3 to 6 nM, making them less displaceable by endogenous dopamine. A relationship exists between the neuroleptic doses for rat catalepsy and the D2/D4 ratio of the intrinsic K values. Thus, the atypical neuroleptics appear to fall into two groups, those that bind loosely to D2 and those that are selective at D4.

A polymorphic dinucleotide repeat in the human dopamine D5 receptor gene promoter

Previously, we have reported the cloning and characterization of the 5'-flanking region of the human dopamine D5 receptor encoding gene (D5) and that the major transactivation domain was 119-182 bp upstream of the transcriptional start site [Beischlag, T.V. et al., Biochemistry, 34 (1995) 5960-5970]. Within this region existed a small dinucleotide repeat termed (TC)13. In this report, we describe the screening of genomic DNAs from 18 unrelated individuals by single-strand conformation polymorphism (SSCP) analysis. SSCP analysis revealed the existence of two additional alleles, termed (TC)12 and (TC)14. Neither form significantly altered D5 promoter-mediated luciferase activity when compared to that of the wild-type control, suggesting that small differences in the number of dinucleotide repeats are not likely of any functional consequence for D5 transactivation.

Two-dimensional Er:YSGG microlaser array pumped with a monolithic two-dimensional laser diode array

We have demonstrated one- and two-dimensional Er:YSGG microlaser arrays at 2.8-microm output wavelength with power levels up to 900 mW cw. The one-dimensional microlaser arrays are based on conventional edge-emitting laser diodes, and the two-dimensional microlaser arrays are based on surface-emitting monolithic two-dimensional laser diode arrays with 45-deg deflectors.

Automated phase sensing and control of an external Talbot cavity laser with phase-contrast imaging

We describe a novel phase-sensing and control system, based on phase-contrast imaging, operating within a linear external cavity laser consisting of 18 GaAlAs edge-emitting gain stripes. The system is used to achieve single-spatial-mode operation and diffraction-limited output from the linear cavity, which uses diffractive coupling at a Talbot plane to achieve coherent operation.

Frequency and clinical significance of erythrocyte genetic abnormalities in Omanis

The frequencies of four malaria associated erythrocyte genetic abnormalities have been established in 1000 Omani subjects. They are: homozygous alpha+ thalassaemia (-alpha/-alpha) 0.45; high Hb A2 beta thalassaemia trait 0.015; sickle trait (Hb A/S) 0.061; and glucose 6 phosphate dehydrogenase deficiency (Gd-): males 0.27, females 0.11. From our data the alpha+ (-alpha/) thal gene (confirmed by Southern blotting) is pandemic in this population. Moreover, in spite of the very high frequency of Gd-, oxidative haemolytic syndromes are very uncommon. Also preliminary data indicate that among the Omani population with sickle cell disease, homozygosity of the alpha+ gene markedly modifies the clinical picture.

Intracavity phase correction of an external Talbot cavity laser with the use of liquid crystals

Arrays of GaAlAs emitters have been diffractively coupled by using an external Talbot cavity to support a single spatial mode; however, element-to-element phase differences distort the desired spatial mode. To enable element-to-element phase correction, we incorporated a 20-element array of tunable liquid-crystal phase shifters into a 20-element GaAlAs external Talbot cavity laser. Using the tunable phase shifters, we corrected spatial mode distortions, which resulted in 663 mW of nearly diffraction-limited power.

Estimation of fibrinogen-fibrin related antigen by continuous flow analysis

A precise method for the determination of fibrinogen-fibrin related antigen (FR antigen) in an automated tanned red cell haemagglutination inhibition system is described. In a continuous flow system aliquots of serum are mixed with a dilution of rabbit anti-human fibrinogen serum. The FR antigen neutralizes the anti-fibrinogen serum and on addition of tanned human red cells sensitized with human fibrinogen, the cells agglutinate according to the remaining anti-fibrinogen activity. The agglutinates are removed and the remaining free cells are haemolysed with saponin and the colour measured at 550 nm. The density of the colour formed is in proportion to the amount of FR antigen present. The range in 102 normal males was 4.8 plus or minus 2.4 mug/ml. A significant increase in the levels of FR antigen throughout pregnancy was found, the highest levels being in the latter half of the third trimester. The levels of FR antigen in 31 normal urines was 0.46 plus or minus 0.44 mug/ml.