An HLA-G/SPAG9/STAT3 axis promotes brain metastases

Brain metastases (BM) are the most common brain neoplasm in adults. Current BM therapies still offer limited efficacy and reduced survival outcomes, emphasizing the need for a better understanding of the disease. Herein, we analyzed the transcriptional profile of brain metastasis initiating cells (BMICs) at two distinct stages of the brain metastatic cascade-the "premetastatic" or early stage when they first colonize the brain and the established macrometastatic stage. RNA sequencing was used to obtain the transcriptional profiles of premetastatic and macrometastatic (non-premetastatic) lung, breast, and melanoma BMICs. We identified that lung, breast, and melanoma premetastatic BMICs share a common transcriptomic signature that is distinct from their non-premetastatic counterparts. Importantly, we show that premetastatic BMICs exhibit increased expression of HLA-G, which we further demonstrate functions in an HLA-G/SPAG9/STAT3 axis to promote the establishment of brain metastatic lesions. Our findings suggest that unraveling the molecular landscape of premetastatic BMICs allows for the identification of clinically relevant targets that can possibly inform the development of preventive and/or more efficacious BM therapies.

EXTH-24. FILAMENTOUS PHAGE AS A NANOTHERANOSTIC FOR THE DETECTION, IMAGING, AND TREATMENT OF GLIOMAS

Current standard of care treatment for gliomas includes maximal safe surgical resection followed by concurrent chemoradiation, however, the diffuse infiltrative nature of gliomas present certain challenges for neurosurgeons to clearly visualize tumor tissue under conventional white light during microsurgical resection. Fluorescence-guided surgical techniques have been recently introduced to help surgeons better visualize tumor tissue under the operating microscope. Fluorescent dyes conjugated to nanoscale materials that are functionalized with glioma-targeting peptide sequences, such as the 39 amino acid chlorotoxin (CTX) peptide sequence, have demonstrated clinical efficacy in recognizing microscopic tumor cells during surgeries. M13 bacteriophage (phage) are versatile, genetically tunable nanocarriers that have been recently adapted for use as theranostic platforms. Applying p3 capsid CTX fusion with a unique “inho” circular single-stranded DNA (cssDNA) gene packaging system, we produced miniature CTX inho (CTX-inho phage particles with a minimum length of 50 nm that can target intracranial orthotopic patient-derived glioblastoma tumors in the brains of mice. Systemically-administered indocyanine green-conjugated CTX-inho phage accumulated in brain tumors, facilitating short-wave infrared detection. Furthermore, we show that our inho phage can carry cssDNA that are transcriptionally active when delivered to GBM22 glioma cells in vitro. The ability to modulate the capsid display, surface loading, phage length, and cssDNA gene content makes the recombinant M13 phage particle an ideal nanotheranostic platform for neuro-oncological applications.

ITVT-03. Use of Functional MRI and DTI for Surgical Planning of Maximal Extent of Resection of CNS Tumors - A Single Neurosurgical Center’s Experience

Use of functional neuroimaging capabilities such as fMRI, DTI, MRP, MRS, AS-PET-CT, SPECT, and TMS as noninvasive tools to visualize intrinsic brain and spine morphology in relation to function have developed over the past 30 years. Amongst these imaging modalities, functional magnetic resonance imaging (fMRI) is of particular interest since it follows the physiological coupling between neuronal electrical activity and metabolic structural (cellular) activity as it relates to tissue vascularity and perfusion states. As an adjunct to this modality, MRI-based diffusion tensor imaging (DTI) allows further detailed radiographic assessment of fiber tracts in the brain in relationship to the surgical lesion of interest. In addition, combination of other imaging modalities including MR perfusion and intraoperative tools such as neuronavigation and direct cortical stimulation can help guide the extent of maximal safe resection. Herein we present a case series from our neurosurgical institution of primary intra-axial, extra-axial, supratentorial, and brainstem tumors resected using fMRI and DTI for presurgical planning allowing for maximal safe extent of resection and outcomes.

CLRM-04. PHASE I/II SAFETY AND EFFICACY STUDY OF BET BROMODOMAIN INHIBITOR OTX-015 WITH OLAPARIB AND LOMUSTINE IN PATIENTS WITH RECURRENT GLIOBLASTOMA

Standard of care for patients with glioblastoma (GBM) includes resection with concurrent temozolomide (TMZ) and radiotherapy, with inevitable disease recurrence. Upon recurrence, tumors are often resistant to first-line therapies and/or have infiltrated eloquent or deep brain regions, precluding repeat resection. There is currently no standard of care for recurrent GBM and patients succumb to their disease burden within 12- 15 months of their initial diagnosis of recurrence, exposing an unmet need to find novel therapies to treat recurrent disease. Bromodomain and extraterminal (BET) proteins are chromatin readers that affect transcription of genes. The oral BET inhibitor (BETi) OTX-015 has shown promise in a dose-escalation, phase I study in patients with acute leukemia and other BET inhibitors are currently in phase I studies for the treatment of primary brain tumors. We have recently shown that BET inhibition increases DNA damage and mitotic catastrophe in oncogenic cells by increasing transcription-replication conflicts and downregulating expression of key DNA damage checkpoint proteins, and have also shown its efficacy in decreasing tumor burden and improving survival when combined with TMZ in intracranial mouse models of glioma. We have also demonstrated that BETi's synergize with Olaparib by downregulating expression of the BRCA-driven DNA damage repair pathway and further leverages additive effects when triply combined with other DNA damaging agents such as Lomustine to decrease tumor burden and improve survival in patient-derived mouse models of GBM and medulloblastoma. We therefore hypothesize that the synergistic and additive effects of this triple combination seen in our preclinical studies will achieve therapeutic benefits in patients with recurrent GBM.

TAMI-03. IDENTIFICATION OF NOVEL DRIVERS OF LUNG-TO-BRAIN METASTASIS THROUGH IN VIVO FUNCTIONAL GENOMICS

Brain metastasis, the most common tumor of the central nervous system, occurs in 20-36% of primary cancers. In particular, 40% of patients with non-small cell lung cancer (NSCLC) develop brain metastases, with a dismal survival of approximately 4-11 weeks without treatment, and 16 months with treatment. This highlights a large unmet need to develop novel targeted therapies for the treatment of lung-to-brain metastases (LBM). Genomic interrogation of LBM using CRISPR technology can inform preventative therapies targeting genetic vulnerabilities in both primary and metastatic tumors. Loss-of-function studies present limitations in metastasis research, as knocking out genes essential for survival in the primary tumor cells can thwart the metastatic cascade prematurely. However, gene overexpression using CRISPR activation (CRISPRa) has the potential for overcoming dependencies of gene essentiality. We theorize that an in vivo genome-wide CRISPRa screen will identify novel genes that, when overexpressed, drive LBM. We have developed a patient-derived orthotopic murine xenograft model of LBM using primary patient-derived NSCLC cell lines (termed LTX cells) from the Swanton Lab TRACERx study. We are now poised to transduce LTX cells with a human genome-wide CRISPRa single guide RNA (sgRNA) library, and to subsequently inject the cells into the lungs of immunocompromised mice. We will then track the process of LBM using bioluminescent and MRI imaging until mice reach endpoint. Sequencing of primary lung tumors and subsequent brain metastases promises to uncover enriched sgRNAs, which may represent novel drivers of primary lung tumor formation and LBM. To the best of our knowledge, this study is the first in vivo genome-wide CRISPRa screen focused on identifying novel drivers of LBM, and can inform future preventative therapies to improve survival outcomes for NSCLC patients.

STEM-01. TARGETING BRAIN METASTASIS-INITIATING CELLS: A PREVENTATIVE APPROACH

BACKGROUND

The incidence of brain metastases (BM) is tenfold higher than primary brain tumors. BM commonly originate from primary lung, breast, and melanoma tumors with a 90% mortality rate within one year of diagnosis. Current standard of care for BM includes surgical resection with concurrent chemoradiation, but does not extend median survival past 16 months, posing a large unmet need to identify novel therapies against BM.

METHODS

From a large in-house biobank of patient-derived BM cell lines, the Singh Lab has generated murine orthotopic patient-derived xenograft (PDX) models of lung, breast, and melanoma BM that recapitulate the stages of BM progression as seen in humans. Using these three PDX models, we identified a population of “pre-metastatic” brain metastasis-initiating cells (BMICs) that are newly arrived in the brain but have yet to form detectable tumors. Pre-metastatic BMICs are not detectable in human patients but are important therapeutic targets with the potential to prevent BM in at-risk patients.

RESULTS

RNA sequencing of pre-metastatic BMICs from all three PDX primary tumor models with subsequent Connectivity Map analysis identified novel compounds that have the potential of killing all three types of BMICs. In particular, we identified two compounds that have selective killing of BMICs in vitro from all three primary tumor cohorts while sparing non-cancerous cells. We further characterized their ability to inhibit the self-renewal and proliferative properties of BMICs. Ongoing in vivo work will investigate the compounds’ preclinical utilities in preventing BM.

CONCLUSION

Identification of novel small molecules that target BMICs could prevent the formation of BM completely and dramatically improve the prognosis of at-risk cancer patients.

Influence of common clinical variables on intraoperative parathyroid hormone monitoring during surgery for primary hyperparathyroidism

BACKGROUND

Intraoperative monitoring of parathyroid hormone (IOPTH) is a reliable method of predicting the cure of primary hyperparathyroidism (PHPT). The aim of this study is to assess whether common clinical variables (CCV) frequently encountered in patients with PHPT may affect the magnitude of PTH drop or the likelihood of patients meeting the intraoperative cure criterion.

DESIGN

Patients who were surgically cured from PHPT caused by single gland disease (SGD) and had full IOPTH protocol (4 measurements) were stratified according to age, gland weight, renal function, vitamin D status and severity of hypercalcemia. The percentage of IOPTH drop and the frequency of patients who had true positive IOPTH test results were compared among groups.

RESULTS

762 patients had surgery for PHPT, of whom 746 were (98%) cured. Of these 746 patients, 511 who had SGD and a full IOPTH protocol were included in this study. The median IOPTH drop was significantly higher among younger patients, those with severe hypercalcaemia at 5, 10, 15 min after gland excision, giant glands (at 5-min only), patients with vitamin D deficiency (at 10, 15 min), and those with normal renal function (at 15 min only). The likelihood of the patients meeting the intraoperative cure criterion was not significantly affected among the groups except in patients with mild hypercalcaemia, who were significantly less likely to have 50% IOPTH drop than those with severe hypercalcaemia at all time points. The frequency of mildly hypercalcaemic patients who met cure criterion was significantly improved by extending measurement to 15 min.

CONCLUSIONS

IOPTH monitoring has the ability to mitigate the variability of IOPTH kinetics associated with most clinical variables. Mildly hypercalcemic patients in particular may benefit from waiting for 15-min measurement before any surgical decision is made.

39. CHARACTERIZING NOVEL INHIBITORS OF BRAIN METASTASIS-INITIATING CELLS

BACKGROUND

The incidence of brain metastases (BM) is tenfold higher than primary brain tumors. BM commonly originate from primary lung, breast, and melanoma tumors with a 90% mortality rate within one year of diagnosis. Current standard of care for BM includes surgical resection with concurrent chemoradiation, but does not extend median survival past 16 months, posing a large unmet need to identify novel therapies against BM.

METHODS

From a large in-house biobank of patient-derived BM cell lines, the Singh Lab has generated murine orthotopic patient-derived xenograft (PDX) models of lung, breast, and melanoma BM that recapitulate the stages of BM progression as seen in human patients. Using these three PDX models, we identified a population of “pre-metastatic” brain metastasis-initiating cells (BMICs) that are newly arrived in the brain but have yet to form detectable tumors. Pre-metastatic BMICs are not detectable in human patients but are important therapeutic targets with the potential to prevent BM in at-risk patients.

RESULTS

RNA sequencing of pre-metastatic BMICs from all three PDX primary tumor models with subsequent Connectivity Map analysis identified novel compounds that have the potential of killing all three types of BMICs. In particular, we identified two compounds that have selective killing of BMICs in vitro from all three primary tumor cohorts while sparing non-cancerous cells. We further characterized their ability to inhibit the self-renewal and proliferative properties of BMICs. Ongoing in vivo work will investigate the compounds’ preclinical utilities in preventing BM.

CONCLUSION

Identification of novel small molecules that target BMICs could prevent the formation of BM completely and dramatically improve the prognosis of at-risk cancer patients.

47. UNCOVERING A NOVEL ROLE FOR HLA-G IN BRAIN METASTASES

Brain metastases (BM) are the most common brain tumour in adults and are ten times more likely to develop than primary brain tumours. More than 20% of patients with cancer will develop BM with the three most common sources being primary cancers of the lung, breast, and melanoma. Unfortunately, current treatment options for BM do not effectively eradicate BM, with a mere median overall survival time of 12 months in treated patients. This indicates the need for better and more effective therapies against BM. Using patient-derived cell lines established from surgically removed brain metastatic tumours of lung-, breast- and melanoma-BM patients, we generated patient-derived orthotopic murine xenograft (PDX) models of lung-, breast-, and melanoma-BM. From these PDX models, we isolated a rare population of stem-like brain metastasis initiating cells (BMICs) we termed “pre-metastatic”, that had traveled from their primary/orthotopic tumours and lodged in the brain but had not yet developed into mature BM. Transcriptomic analyses performed on pre-metastatic and non-pre-metastatic BMICs from lung, breast and melanoma PDX models of BM, identified a set of deregulated genes exclusive only to pre-metastatic BMICs. Further analysis revealed HLA-G as being commonly up-regulated only during the pre-metastatic stage of the lung-, breast-, and melanoma-BM cascade. In vitro and in vivo analyses demonstrated that HLA-G knock-down reduced the proliferation and survival of BMICs from all BM cohorts, and attenuated the establishment of mature brain metastatic tumours, implying a crucial role for HLA-G in the formation of BM. Developing a therapeutic strategy that targets HLA-G in BM may prove effective at completely eliminating brain metastatic cells at an early stage of the BM cascade, thereby turning a fatal disease into an eminently more treatable one.

37. IN VIVO FUNCTIONAL GENOMIC SCREEN TO IDENTIFY NOVEL DRIVERS OF LUNG-TO-BRAIN METASTASIS

Brain metastasis, the most common tumour of the central nervous system, occurs in 20–36% of primary cancers. In particular, 40% of patients with non-small cell lung cancer (NSCLC) develop brain metastases, with a dismal survival of approximately 4–11 weeks without treatment, and 16 months with treatment. This highlights a large unmet need to develop novel targeted therapies for the treatment of lung-to-brain metastases (LBM). Genomic interrogation of LBM using CRISPR technology can inform preventative therapies targeting genetic vulnerabilities in both primary and metastatic tumours. Loss-of-function studies present limitations in metastasis research, as knocking out genes essential for survival in the primary tumour cells can thwart the metastatic cascade prematurely. However, gene overexpression using CRISPR activation (CRISPRa) has the potential for overcoming dependencies of gene essentiality. We theorize that an in vivo genome-wide CRISPRa screen will identify novel genes that, when overexpressed, drive LBM. We have developed a patient-derived orthotopic murine xenograft model of LBM using primary patient-derived NSCLC cell lines (termed LTX cells) from the Swanton Lab TRACERx study. We are now poised to transduce LTX cells with a human genome-wide CRISPRa single guide RNA (sgRNA) library, and to subsequently inject the cells into the lungs of immunocompromised mice. We will then track the process of LBM using bioluminescent and MRI imaging until mice reach endpoint. Sequencing of primary lung tumours and subsequent brain metastases promises to uncover enriched sgRNAs, which may represent novel drivers of primary lung tumour formation and LBM. To the best of our knowledge, this study is the first in vivo genome-wide CRISPRa screen focused on identifying novel drivers of LBM, and can inform future preventative therapies to improve survival outcomes for NSCLC patients.

Ascending-Dose Study of Controlled-Release Ketamine Tablets in Healthy Volunteers: Pharmacokinetics, Pharmacodynamics, Safety, and Tolerability

Parenteral ketamine has fast-onset antidepressant and antianxiety effects; however, it causes dissociation, hypertension, and tachycardia shortly after dosing. Ketamine's antidepressant effects may be due to active metabolites rather than to ketamine itself. We hypothesized that oral controlled-release ketamine tablets would improve safety and tolerability compared with injected ketamine by reducing peak ketamine exposures compared with dosing by injection. In this randomized, placebo-controlled ascending-dose study, ketamine doses of 60, 120, or 240 mg or matching placebo (single dose followed by every-12-hours dosing for 5 doses) were given to 24 healthy volunteers. Pharmacokinetics, pharmacodynamics (brain-derived neurotropic factor), adverse events, and vital signs were assessed up to 72 hours. Drug release occurred over ∼10 hours, with most drug substance present as norketamine (∼90%). Area under the concentration-time curve and peak concentration were dose proportional. Elimination half-life was prolonged (7-9 hours) compared with published data from immediate-release oral formulations. There were no changes in blood pressure or heart rate after any dose. Mild dissociation was reported after 240 mg but not lower doses; mean dissociation ratings in this group were minimal (1-2/76). There were no clinically significant changes in ECGs or safety laboratory tests at any time. Compared with injected ketamine, oral controlled-release ketamine tablets did not increase blood pressure or heart rate, and only at doses of 240 mg was dissociation of mild intensity reported. Reducing and delaying ketamine peak concentration by oral dosing with controlled-release ketamine tablets improve this drug's tolerability for patients with depression/anxiety.

Safety and efficacy of extended release ketamine tablets in patients with treatment-resistant depression and anxiety: open label pilot study

BACKGROUND

Ketamine's defining side effects are dissociation and increased blood pressure/heart rate. An oral formulation with delayed absorption could minimize these effects. We recently reported safety and tolerability data for an extended release ketamine tablet in healthy volunteers.

METHODS

To assess safety, tolerability, efficacy, and pharmacokinetics of an extended release oral ketamine tablet in patients with treatment-resistant depression/anxiety. This was a multiple dose open-label flexible dose uncontrolled study in seven patients with treatment-resistant depression/anxiety, who had all previously demonstrated mood improvement to subcutaneous ketamine. Assessments included ratings of anxiety, depression and dissociation, safety and tolerability, and blood samples for ketamine pharmacokinetics and brain-derived neurotrophic factor (BDNF) concentrations.

RESULTS

Improvements in anxiety and depression ratings occurred gradually over 96 h; all patients had >50% improvements in mood ratings. Ketamine was safe and well tolerated, with no changes in vital signs, and a single brief report of dissociation. Ketamine may induce its own metabolism, as the ratio of norketamine to ketamine increased out to 96 h. Serum BDNF concentrations did not change during the study.

CONCLUSION

Ketamine's safety/tolerability may be improved with an extended release oral formulation. Onset of mood improvement is slightly delayed compared with parenteral dosing. These data support the further development of extended release ketamine tablets for treatment of resistant depression and anxiety disorders.

Antibody-targeting of ultra-small nanoparticles enhances imaging sensitivity and enables longitudinal tracking of multiple myeloma

Monitoring malignant progression and disease recurrence post-therapy are central challenges to improving the outcomes of patients with multiple myeloma (MM). Whereas current detection methods that rely upon bone marrow examination allow for precise monitoring of minimal residual disease and can help to elucidate clonal evolution, they do not take into account the spatial heterogeneity of the tumor microenvironment. As such, they are uninformative as to the localization of malignant plasma cells and may lead to false negative results. With respect to the latter challenge, clinically-available imaging agents are neither sufficiently sensitive nor specific enough to detect minute plasma cell populations. Here, we sought to explore methods by which to improve detection of MM cells within their natural bone marrow environment, using whole-animal magnetic resonance imaging to longitudinally monitor early-stage disease as well as to enhance tumor detection after systemic therapy. We conducted a proof-of-concept study to demonstrate that ultra-small (<5 nm) gadolinium-containing nanoparticles bound to full-length antibodies against the B-cell maturation antigen (BCMA) exhibit rapid tumor uptake followed by renal clearance, improving the signal-to-noise ratio for MM detection beyond levels that are currently afforded by other FDA-approved clinical imaging modalities. We anticipate that when combined with bone marrow or blood biopsy, such imaging constructs could help to augment the effective management of patients with MM.

The evolution of methods for urinary steroid metabolomics in clinical investigations particularly in childhood

The metabolites of cortisol, and the intermediates in the pathways from cholesterol to cortisol and the adrenal sex steroids can be analysed in a single separation of steroids by gas chromatography (GC) coupled to MS to give a urinary steroid profile (USP). Steroids individually and in profile are now commonly measured in plasma by liquid chromatography (LC) coupled with MS/MS. The steroid conjugates in urine can be determined after hydrolysis and derivative formation and for the first time without hydrolysis using GC-MS, GC-MS/MS and liquid chromatography with mass spectrometry (LC-MS/MS). The evolution of the technology, practicalities and clinical applications are examined in this review. The patterns and quantities of steroids changes through childhood. Information can be obtained on production rates, from which children with steroid excess and deficiency states can be recognised when presenting with obesity, adrenarche, adrenal suppression, hypertension, adrenal tumours, intersex condition and early puberty, as examples. Genetic defects in steroid production and action can be detected by abnormalities from the GC-MS of steroids in urine. New mechanisms of steroid synthesis and metabolism have been recognised through steroid profiling. GC with tandem mass spectrometry (GC-MS/MS) has been used for the tentative identification of unknown steroids in urine from newborn infants with congenital adrenal hyperplasia. Suggestions are made as to areas for future research and for future applications of steroid profiling. As routine hospital laboratories become more familiar with the problems of chromatographic and MS analysis they can consider steroid profiling in their test repertoire although with LC-MS/MS of urinary steroids this is unlikely to become a routine test because of the availability, cost and purity of the internal standards and the complexity of data interpretation. Steroid profiling with quantitative analysis by mass spectrometry (MS) after chromatography now provides the most versatile of tests of adrenal function in childhood.

Anesthesia for patients with tracheal bronchus

Tracheal bronchus is a congenital anatomical variant of patients with accessory bronchus in the right upper lobe deriving directly from the supracarinal trachea. Pre-operative consultation with the anesthesiologist is important for patient safety and can avoid adverse effects induced by endotracheal intubation. In this report, we described a case of tracheal bronchus in which general anesthesia was performed for video-assisted thoracoscopic surgery. We discussed some of the issues surrounding to complications in tracheal bronchus.

Ascending Single-Dose, Double-Blind, Placebo-Controlled Safety Study of Noribogaine in Opioid-Dependent Patients

Ibogaine is a psychoactive substance that may reduce opioid withdrawal symptoms. This was the first clinical trial of noribogaine, ibogaine's active metabolite, in patients established on methadone opioid substitution therapy (OST). In this randomized, double-blind, placebo-controlled single ascending-dose study, we evaluated the safety, tolerability, and pharmacokinetics of noribogaine in 27 patients seeking to discontinue methadone OST who had been switched to morphine during the previous week. Noribogaine doses were 60, 120, or 180 mg (n = 6/dose level) or matching placebo (n = 3/dose level). Noribogaine was well tolerated. The most frequent treatment-emergent adverse events were noneuphoric changes in light perception ∼1 hour postdose, headache, and nausea. Noribogaine had dose-linear increases for AUC and C_max and was slowly eliminated (mean t_1/2 range, 24-30 hours). There was a concentration-dependent increase in QTcI (0.17 ms/ng/mL), with the largest observed mean effect of ∼16, 28, and 42 milliseconds in the 60-, 120-, and 180-mg groups, respectively. Noribogaine showed a nonstatistically significant trend toward decreased total score in opioid withdrawal ratings, most notably at the 120-mg dose; however, the study design may have confounded evaluations of time to resumption of OST. Future exposure-controlled multiple-dose noribogaine studies are planned that will address these safety and design issues.

Poly (I:C) therapy decreases cerebral ischaemia/reperfusion injury via TLR3-mediated prevention of Fas/FADD interaction

Toll-like receptor (TLR)-mediated signalling plays a role in cerebral ischaemia/reperfusion (I/R) injury. Modulation of TLRs has been reported to protect against cerebral I/R injury. This study examined whether modulation of TLR3 with poly (I:C) will induce protection against cerebral I/R injury. Mice were treated with or without Poly (I:C) (n = 8/group) 1 hr prior to cerebral ischaemia (60 min.) followed by reperfusion (24 hrs). Poly (I:C) pre-treatment significantly reduced the infarct volume by 57.2% compared with untreated I/R mice. Therapeutic administration of Poly (I:C), administered 30 min. after cerebral ischaemia, markedly decreased infarct volume by 34.9%. However, Poly (I:C)-induced protection was lost in TLR3 knockout mice. In poly (I:C)-treated mice, there was less neuronal damage in the hippocampus compared with untreated I/R mice. Poly (I:C) treatment induced IRF3 phosphorylation, but it inhibited NF-κB activation in the brain. Poly (I:C) also decreased I/R-induced apoptosis by attenuation of Fas/FasL-mediated apoptotic signalling. In addition, Poly (I:C) treatment decreased microglial cell caspase-3 activity. In vitro data showed that Poly (I:C) prevented hypoxia/reoxygenation (H/R)-induced interaction between Fas and FADD as well as caspase-3 and -8 activation in microglial cells. Importantly, Poly (I:C) treatment induced co-association between TLR3 and Fas. Our data suggest that Poly (I:C) decreases in cerebral I/R injury via TLR3 which associates with Fas, thereby preventing the interaction of Fas and FADD, as well as microglial cell caspase-3 and -8 activities. We conclude that TLR3 modulation by Poly (I:C) could be a potential approach for protection against ischaemic stroke.

Enhanced 3-epi-25-hydroxyvitamin D3 signal leads to overestimation of its concentration and amplifies interference in 25-hydroxyvitamin D LC-MS/MS assays

Background

3-epi-25-hydroxyvitamin D3 (3-epi-25OHD3) interferes in most liquid chromatography-tandem mass spectrometry (LC-MS/MS) assays for 25-hydroxyvitamin D (25OHD). The clinical significance of this is unclear, with concentrations from undetectable to 230 nmol/L reported. Many studies have quantified 3-epi-25OHD3 based on 25OHD3 calibrators or other indirect methods, and we speculated that this contributes to the observed variability in reported 3-epi-25OHD3 concentrations.

Methods

We compared continuous MS/MS infusions of 3-epi-25OHD3 and 25OHD3 solutions, spiked both analytes into the same serum matrix and analysed patient samples to assess the effect of three different quantitation methods on 3-epi-25OHD3 concentration. Experiments were performed on an LC-MS/MS system using a phenyl column which does not resolve 3-epi-25OHD3, and a modified method utilizing a Zorbax SB-CN column that chromatographically resolves 3-epi-25OHD3 from 25OHD3.

Results

A greater 3-epi-25OHD3 signal, compared with 25OHD3, was observed during equimolar post-column continuous infusion of analyte solutions, and following analysis of a serum pool spiked with both analytes. 3-epi-25OHD3 signal enhancement was dependent on mobile phase composition. Compared with 3-epi-25OHD3 calibrators, indirect quantitation methods resulted in up to 10 times as many samples having 3-epi-25OHD3 concentrations ≥ 10 nmol/L, and an approximately fourfold increase in the maximum observed 3-epi-25OHD3 concentration to 95 nmol/L.

Conclusions

Enhanced 3-epi-25OHD3 signal leads to overestimation of its concentrations in the indirect quantitation methods used in many previous studies. The enhanced signal may contribute to greater interference in some 25OHD LC-MS/MS assays than others. We highlight that equimolar responses cannot be assumed in LC-MS/MS systems, even if two molecules are structurally similar.

Open repair of massive rotator cuff tears in patients aged sixty-five years or over: is it worthwhile?

The purpose of the study was to evaluate the functional outcome and identify possible preoperative prognostic factors in patients aged 65 years or over undergoing open repair for a massive (>5 cm) full-thickness rotator cuff tear. Patients were assessed after a mean of 48 months by an independent observer by use of the Constant score and the Oxford Shoulder Questionnaire. The outcome was excellent or good in 44% and poor in 23%. The patient satisfaction rate was 84%. Pain relief was obtained in 93%. We found three preoperative variables to be significantly associated with a poor outcome: female sex, duration of symptoms greater than 34 months before surgery, and American Society of Anesthesiologists grade. The results of our study suggest that appropriately selected patients who are aged 65 years or over with a massive full-thickness rotator cuff tear can be expected to have a good functional outcome and pain relief after repair.

Open repair of massive rotator cuff tears in patients aged sixty-five years or over: is it worthwhile?

The purpose of the study was to evaluate the functional outcome and identify possible preoperative prognostic factors in patients aged 65 years or over undergoing open repair for a massive (>5 cm) full-thickness rotator cuff tear. Patients were assessed after a mean of 48 months by an independent observer by use of the Constant score and the Oxford Shoulder Questionnaire. The outcome was excellent or good in 44% and poor in 23%. The patient satisfaction rate was 84%. Pain relief was obtained in 93%. We found three preoperative variables to be significantly associated with a poor outcome: female sex, duration of symptoms greater than 34 months before surgery, and American Society of Anesthesiologists grade. The results of our study suggest that appropriately selected patients who are aged 65 years or over with a massive full-thickness rotator cuff tear can be expected to have a good functional outcome and pain relief after repair.

Limb loss following the use of heparin. A lesson to be remembered

The optimal method of prophylaxis against venous thromboembolism after total hip replacement (THR) remains uncertain. Most surgeons use some form of pharmacological prophylaxis, most commonly heparin. The precise balance of the benefits and risks is unclear, and serious complications can occur. We describe a case of heparin-induced thrombocytopenia and thrombosis syndrome in a 62-year-old woman after THR.

LIMB LOSS FOLLOWING THE USE OF HEPARIN

The optimal method of prophylaxis against venous thromboembolism after total hip replacement (THR) remains uncertain. Most surgeons use some form of pharmacological prophylaxis, most commonly heparin. The precise balance of the benefits and risks is unclear, and serious complications can occur. We describe a case of heparin-induced thrombocytopenia and thrombosis syndrome in a 62-year-old woman after THR.

Traumatic asymmetrical bilateral hip dislocation in an adult

Bilateral hip dislocation occurring as a result of trauma is a rare condition. Simultaneous anterior and posterior traumatic dislocation of both hips is even more unusual. A case is reported of asymmetrical bilateral traumatic hip dislocation without an associated fracture of the pelvis or femur occurring in a young adult with no previous history of hip abnormality or ligamentous laxity. An unusual mechanism for this injury is also described.

Selection analyses of insertional mutants using subgenic-resolution arrays

We describe a method of genome-wide analysis of quantitative growth phenotypes using insertional mutagenesis and DNA microarrays. We applied the method to assess the fitness contributions of Escherichia coli gene domains under specific growth conditions. A transposon library was subjected to competitive growth selection in Luria-Bertani (LB) and in glucose minimal media. Transposon-containing genomic DNA fragments from the selected libraries were compared with the initial unselected transposon insertion library on DNA microarrays to identify insertions that affect fitness. Genes involved in the biosynthesis of nutrients not provided in the growth medium were found to be significantly enriched in the set of genes containing negatively selected insertions. The data also identify fitness contributions of several uncharacterized genes, including putative transcriptional regulators and enzymes. The applicability of this high-resolution array selection in other species is discussed.

Clinical and cost-effectiveness of continuous subcutaneous terbutaline versus oral tocolytics for treatment of recurrent preterm labor in twin gestations

OBJECTIVE

To compare the clinical and cost-effectiveness of treating recurrent preterm labor with continuous subcutaneous terbutaline versus oral tocolytics in twin gestations.

STUDY DESIGN

In a retrospective, matched-cohort design, twin pregnancies treated as outpatients with continuous subcutaneous terbutaline were identified from a perinatal database, then matched 1:1 by gestational age at recurrent preterm labor to those receiving oral tocolytics. There were 353 patients per treatment group. A cost model was used to compare antepartum hospital, nursery, and outpatient charges.

RESULTS

Infants of the subcutaneous terbutaline group had greater gestational age at delivery, higher birth weights, and less frequent neonatal intensive care unit admission. Charges for antepartum hospitalization and nursery were significantly less in the subcutaneous terbutaline group, while charges for outpatient services were less for the oral group. Mean total estimated charges were US$17,109 less for those receiving subcutaneous terbutaline.

CONCLUSION

Improved clinical outcomes and decreased nursery utilization suggest cost-effectiveness of outpatient continuous subcutaneous terbutaline versus oral tocolytics for the treatment of recurrent preterm labor.

Adherence to antibiotics prescribed in an accident and emergency department: the influence of consultation factors

The objective of this study was to investigate the extent of non-adherence to prescribed antibiotics and the relationship of non-adherence to consultation and attitudinal factors. Self-completion postal questionnaires were sent to 202 consecutive adult attenders to an accident and emergency (A&E) department who had been given antibiotics to take home, within a week of the A&E attendance. The questionnaire included a detailed log of dosing, two sections of eight questions each on the patients' perceptions of the consultation and of their attitudes to medicines in general, which were marked on Likert scales; and questions inviting free text answers. Efforts were made to maximize the response rate, and to contact a random sample of 10 non-responders to assess any non-response bias. The response rate was 56%. The non-responders sampled reported similar non-adherence to that of the responders. Of the 113 responders, 10 (9%) indicated that they had taken none of their prescribed medicines, and 25 (22%) that they had taken less than 80%. The most common pattern of non-adherence was early cessation. Two aspects of the consultation (expectations about a prescription, and that there were too many tablets) were related to adherence. In conclusion, this study suggests that the effectiveness of some A&E consultations is reduced by inadequate exploration of patients' concerns and expectations.

A comparison of gestational days gained with oral terbutaline versus continuous subcutaneous terbutaline in women with twin gestations

OBJECTIVE

To compare gestational days gained with oral versus subcutaneous terbutaline for maintenance tocolysis.

STUDY DESIGN

In retrospective fashion 386 women enrolled in an outpatient preterm labor identification program met the following criteria: twin gestation, development of threatened preterm labor resulting in treatment with oral terbutaline, and subsequent recurrence of threatened preterm labor resulting in treatment with continuous subcutaneous terbutaline. The primary outcome was gestational days gained with oral terbutaline versus gain with continuous subcutaneous terbutaline.

RESULTS

There were significantly more days gained during subcutaneous treatment than during oral treatment (34.0 +/- 19.8 versus 19.3 +/- 15.3 days). Thirty-three percent of desired prolongation was achieved with oral terbutaline, whereas 79% of desired prolongation was achieved with subcutaneous terbutaline (p < 0.001). Patients gained a mean of 53.4 +/- 21.4 days overall with outpatient tocolysis. The mean gestational age at delivery was 35.2 +/- 1.9 weeks.

CONCLUSION

Continuous subcutaneous terbutaline was superior to oral terbutaline in prolonging gestation in women with twin gestations.

Predicting BMI in young adults from childhood data using two approaches to modelling adiposity rebound

OBJECTIVE

To identify the age of adiposity rebound and the value of its associated BMI and examine their association with BMI at ages 18 and 21 y for males and females.

DESIGN

A longitudinal study of a large cohort of people born in Dunedin, New Zealand between 1972-1973.

SUBJECTS

Four hundred and seventy-four males and 448 females aged between birth and 21 y.

MEASUREMENTS

BMI was derived from measurements of weight and height made when the participants were born and at intervals from age 3-21 y.

RESULTS

When a random coefficients model was fitted to the data for those who had five or more measures of BMI between age 3 and age 18y, adiposity rebound occurred at 6.0 y of age for boys and 5.6y for girls. The values of BMI associated with these were 15.7 kg/m2 for boys and 15.5 kg/m2 for girls. The correlations between age at adiposity rebound and BMI at ages 18 and 21 y were between -0.72 and -0.65 for boys and -0.59 and -0.47 for girls. These were higher than those derived from fitting individual curves or from deriving the adiposity rebound from data collected up to age 11 y. The correlation between BMI at age 7y and BMI at ages 18 and 21 y were 0.70 and 0.61 for boys and 0.56 and 0.52 for girls. The correlations between measures of skeletal maturity at age 7y and adiposity rebound were statistically significant for boys but not for girls.

CONCLUSIONS

BMI in early adulthood was associated with both age of adiposity rebound and BMI at that age. As the correlations between BMI at age 7 y and BMI at ages 18 and 21 y were similar in magnitude, BMI at age 7 y may be a more practical way of predicting BMI in early adulthood.

Clinical issues surrounding the use of terbutaline sulfate for preterm labor

beta-mimetics have been prescribed by physicians to arrest or prevent premature labor for more than 20 years. Although not approved by the Food and Drug Administration (FDA) for tocolytic use, terbutaline sulfate has been the most widely prescribed beta-mimetic in the United States. Recently, the role of terbutaline in the treatment and prevention of preterm labor has been questioned by the FDA. Because the off-label use of drugs is a formally accepted practice in medicine when scientific studies support such use, we reviewed the currently available clinical literature on terbutaline use in various routes of delivery: intravenous, oral, and subcutaneous via infusion pump. This review describes the clinical evidence that supports the safe and effective use of terbutaline as a tocolytic agent in certain patient populations. Practicing physicians should continue to have unrestricted use of terbutaline for tocolysis as one of the few remaining therapeutic options remaining in the fight against preterm birth.

Regulation of amyloid precursor protein catabolism involves the mitogen-activated protein kinase signal transduction pathway

Catabolic processing of the amyloid precursor protein (APP) is subject to regulatory control by protein kinases. We hypothesized that this regulation involves sequential activation of the enzymes mitogen-activated protein kinase kinase (MEK) and extracellular signal-regulated protein kinase (ERK). In the present investigation, we provide evidence that MEK is critically involved in regulating APP processing by both nerve growth factor and phorbol esters. Western blot analysis of the soluble N-terminal APP derivative APPs demonstrated that the synthetic MEK inhibitor PD 98059 antagonized nerve growth factor stimulation of both APPs production and ERK activation in PC12 cells. Moreover, PD 98059 inhibited phorbol ester stimulation of APPs production and activation of ERK in both human embryonic kidney cells and cortical neurons. Furthermore, overexpression of a kinase-inactive MEK mutant inhibited phorbol ester stimulation of APP secretion and activation of ERK in human embryonic kidney cell lines. Most important, PD 98059 antagonized phorbol ester-mediated inhibition of Abeta secretion from cells overexpressing human APP695 carrying the "Swedish mutation." Taken together, these data indicate that MEK and ERK may be critically involved in protein kinase C and nerve growth factor regulation of APP processing. The mitogen-activated protein kinase cascade may provide a novel target for altering catabolic processing of APP.

The incidence of post dural puncture headache in children

One hundred and five children with malignant disease attended for lumbar puncture which was performed under general anaesthesia. A questionnaire was answered over the next three days to determine the incidence of post dural puncture headache Ninety-seven questionnaires were returned and the results show that no child aged under ten years developed a headache. Of the children aged 10-12 years, two out of seventeen developed a headache (11.8%). In children aged 13-18 years, five out of ten developed a headache (50%).

Growth suppression by p16ink4 requires functional retinoblastoma protein

p16ink4 has been implicated as a tumor suppressor that is lost from a variety of human tumors and human cell lines. p16ink4 specifically binds and inhibits the cyclin-dependent kinases 4 and 6. In vitro, these kinases can phosphorylate the product of the retinoblastoma tumor suppressor gene. Thus, p16ink4 could exert its function as tumor suppressor through inhibition of phosphorylation and functional inactivation of the retinoblastoma protein. Here we show that overexpression of p16ink4 in certain cell types will lead to an arrest in the G1 phase of the cell cycle. In addition, we show that p16ink4 can only suppress the growth of human cells that contain functional pRB. Moreover, we have compared the effect of p16ink4 expression on embryo fibroblasts from wild-type and RB homozygous mutant mice. Wild-type embryo fibroblasts are inhibited by p16ink4, whereas the RB nullizygous fibroblasts are not. These data not only show that the presence of pRB is crucial for growth suppression by p16ink4 but also indicate that the pRB is the critical target acted upon by cyclin D-dependent kinases in the G1 phase of the cell cycle.