A robust experimental and computational analysis framework at multiple resolutions, modalities and coverages.

The ability to study cancer-immune cell communication across the whole tumor section without tissue dissociation is needed, especially for cancer immunotherapy development, which requires understanding of molecular mechanisms and discovery of more druggable targets. In this work, we assembled and evaluated an integrated experimental framework and analytical process to enable genome-wide scale discovery of ligand-receptors potentially used for cellular crosstalks, followed by targeted validation. We assessed the complementarity of four different technologies: single-cell RNA sequencing and Spatial transcriptomic (measuring over >20,000 genes), RNA In Situ Hybridization (RNAscope, measuring 4-12 genes) and Opal Polaris multiplex protein staining (4-9 proteins). To utilize the multimodal data, we implemented existing methods and also developed STRISH (Spatial TRanscriptomic In Situ Hybridization), a computational method that can automatically scan across the whole tissue section for local expression of gene (e.g. RNAscope data) and/or protein markers (e.g. Polaris data) to recapitulate an interaction landscape across the whole tissue. We evaluated the approach to discover and validate cell-cell interaction in situ through in-depth analysis of two types of cancer, basal cell carcinoma and squamous cell carcinoma, which account for over 70% of cancer cases. We showed that inference of cell-cell interactions using scRNA-seq data can misdetect or detect false positive interactions. Spatial transcriptomics still suffers from misdetecting lowly expressed ligand-receptor interactions, but reduces false discovery. RNAscope and Polaris are sensitive methods for defining the location of potential ligand receptor interactions, and the STRISH program can determine the probability that local gene co-expression reflects true cell-cell interaction. We expect that the approach described here will be widely applied to discover and validate ligand receptor interaction in different types of solid cancer tumors.

Oral Health Indicators for Risk of Malnutrition in Elders.

OBJECTIVES: Using both clinical parameters and subjective measures of oral health, this study aimed to identify useful oral health indicators for the risk of malnutrition in elders. DESIGN: Cross-sectional study. SETTING: Five community centers run by non-government organizations (NGOs). PARTICIPANTS: 195 community dwelling elders (65 or above). MEASUREMENTS: An interviewer-administered questionnaire was completed to collect information on elders' socio-demographic background and oral health perception and practice. Their number of teeth, number of occluding tooth pairs, dental caries, and periodontal condition were examined. General Oral Health Assessment Index (GOHAI), an instrument for assessing oral health related quality of life (OHQoL), was used as a subjective measure of oral health. The elders' nutritional status was evaluated by using the Mini-Nutritional Assessment (MNA). RESULTS: The mean (SD) DFT was 3.3 (3.1). Over 60% of elders had periodontal pockets; 33% had fewer than 20 teeth and 6% were edentulous. The mean (SD) of occluding tooth pairs was 7.1 (4.8). The mean (SD) total GOHAI score was 56.4 (8.0); 60% reported negative impact of oral health on their quality of life. The mean (SD) MNA score was 25.0 (2.9); 30% had malnutrition or were at risk. After controlling for socio-demographic factors, none of the clinical indicators (dental caries, periodontal status, number of teeth, and number of occluding tooth pairs) were associated with risk of malnutrition (all p>0.05). Poorer OHQoL indicated a higher chance for malnutrition in both adjusted models (OR of 0.914; 95% CI of 0.850-0.982; p=0.014 and OR of 0.915; 95% CI of 0.852-0.984; p=0.017). Tooth loss and untreated decayed teeth (DT) were significant/marginally significant determinants of poor OHQoL. CONCLUSION: Elders' tooth loss and unmet treatment need for dental caries were associated with compromised quality of life, which indicated increased likelihood for malnutrition.

Uncoiling collagen: a multidimensional mass spectrometry study.

Mass spectrometry can be used to determine structural information about ions by activating precursors and analysing the resulting series of fragments. Two-dimensional Fourier transform ion cyclotron resonance mass spectrometry (2D FT-ICR MS) is a technique that correlates the mass-to-charge (m/z) ratio of fragment and precursor ions in a single spectrum. 2D FT-ICR MS records the fragmentation of all ions in a sample without the need for isolation. To analyse specific precursors, horizontal cross-sections of the spectrum (fragment ion scans) are taken, providing an alternative to conventional tandem mass spectrometry (MS/MS) experiments. In this work, 2D FT-ICR MS has been used to study the tryptic digest of type I collagen, a large protein. Fragment ion scans have been extracted from the 2D FT-ICR MS spectrum for precursor m/z ratios: 951.81, 850.41, 634.34, and 659.34, and 2D FT-ICR MS spectra are compared with a set of 1D MS/MS spectra using different fragmentation methods. The results show that two-dimensional mass spectrometry excells at MS/MS of complex mixtures, simplifying spectra by eliminating contaminant peaks, and aiding the identification of species in the sample. Currently, with desktop computers, 2D FT-ICR MS is limited by data processing power, a limitation which should be alleviated using cluster parallel computing. In order to explore 2D FT-ICR MS for collagen, with reasonable computing time, the resolution in the fragment ion dimension is limited to 256k data points (compared to 4M data points in 1D MS/MS spectra), but the vertical precursor ion dimension has 4096 lines, so the total data set is 1G data points (4 Gbytes). The fragment ion coverage obtained with a blind, unoptimized 2D FT-ICR MS experiment was lower than conventional MS/MS, but MS/MS information is obtained for all ions in the sample regardless of selection and isolation. Finally, although all 2D FT-ICR MS peak assignments were made with the aid of 1D FT-ICR MS data, these results demonstrate the promise of 2D FT-ICR MS as a technique for studying complex protein digest mixtures.

The potential application of a transcriptionally regulated oncolytic herpes simplex virus for human cancer therapy.

BACKGROUND: Emerging studies have shown the potential benefit of arming oncolytic viruses with therapeutic genes. However, most of these therapeutic genes are placed under the regulation of ubiquitous viral promoters. Our goal is to generate a safer yet potent oncolytic herpes simplex virus type-1 (HSV-1) for cancer therapy. METHODS: Using bacterial artificial chromosome (BAC) recombineering, a cell cycle-regulatable luciferase transgene cassette was replaced with the infected cell protein 6 (ICP6) coding region (encoded for UL39 or large subunit of ribonucleotide reductase) of the HSV-1 genome. These recombinant viruses, YE-PC8, were further tested for its proliferation-dependent luciferase gene expression. RESULTS: The ability of YE-PC8 to confer proliferation-dependent transgene expression was demonstrated by injecting similar amount of viruses into the tumour-bearing region of the brain and the contralateral normal brain parenchyma of the same mouse. The results showed enhanced levels of luciferase activities in the tumour region but not in the normal brain parenchyma. Similar findings were observed in YE-PC8-infected short-term human brain patient-derived glioma cells compared with normal human astrocytes. intratumoural injection of YE-PC8 viruses resulted in 77% and 80% of tumour regression in human glioma and human hepatocellular carcinoma xenografts, respectively. CONCLUSION: YE-PC8 viruses confer tumour selectivity in proliferating cells and may be developed further as a feasible approach to treat human cancers.

Human mesenchymal stem cells and their paracrine factors for the treatment of brain tumors.

Glioblastoma multiforme (GBM or World Health Organization (WHO) grade IV) is the most malignant tumor of the brain. Despite conventional combination treatment of surgery, radiotherapy and chemotherapy, the survival of patients with GBM is generally <1 year. It is a great challenge to identify an effective drug that could efficiently inhibit (i) the growth of cancer cells; (ii) angiogenesis; (iii) metastasis; (iv) tumor-associated inflammation; (v) inactivate proliferative signal, (vi) induce specific apoptosis, and yet causes minimal harm to normal cells. Mesenchymal stem cells (MSCS) do possess some unique features (inherent tumor tropism; anti-inflammatory and immunosuppressive properties) that are not commonly found in current anticancer agents. These cells are known to secrete a vast array of proteins including growth factors, cytokines, chemokines and so on that regulate their biology in an autocrine or paracrine manner in accordance to the surrounding microenvironment. This review briefly summarizes the biology of MSCs and discusses their properties and new development for brain cancer treatment.

Suicidal gene therapy in the effective control of primary human hepatocellular carcinoma as monitored by noninvasive bioimaging.

Hepatocellular carcinoma (HCC) is usually refractory to the available treatments. For cancer gene therapy purposes, real-time imaging of therapeutic gene expression is of great importance because there are multiple factors that modulate the therapeutic gene expression in a complex tumor microenvironment. As a consequence, multiple doses of therapeutic viral vectors may be required for improved efficacy. In the present study, the luciferase reporter gene and the yeast cytosine deaminase (yCD) genes were bicistronically expressed using the foot-and-mouth disease virus 2A peptide under the regulation of the cytomegalovirus (CMV) promoter. The effectiveness of the yCD/5-FC (5-fluorocytosine) killing efficacy mediated by the herpes simplex virus type 1 (HSV-1) amplicon viral vector was shown using HCC and non-HCC cell lines in vitro. In addition, in vivo experiment also showed tumor regression of a primary HCC 26-1004 tumor xenograft in tumor expressing high levels of the yCD gene (as determined by noninvasive imaging) after intratumoral injection of 1.5 × 10(6) TU HGCX-L2C HSV-1 amplicon viral vector and 5-FC administration. The HSV-1 amplicon viral vector coupled with the yCD/5-FC prodrug activated suicide gene could potentially be of use in clinical gene therapy for HCC.

Targeting human glioma cells using HSV-1 amplicon peptide display vector.

Targeting cell infection using herpes simplex virus type 1 (HSV-1) vectors is a complicated issue as the process involves multiple interactions of viral envelope glycoproteins and cellular host surface proteins. In this study, we have inserted a human glioma-specific peptide sequence (denoted as MG11) into a peptide display HSV-1 amplicon vector replacing the heparan sulfate-binding domain of glycoprotein C (gC). The modified MG11:gC envelope recombinant vectors were subsequently packaged into virions in the presence of helper virus deleted for gC. Our results showed that the tropism of these HSV-1 recombinant virions was increased for human glioma cells in culture as compared with wild-type virions. The binding of these recombinant virions could also be blocked effectively by pre-incubating the cells with the glioma-specific peptide, indicating that MG11 peptide and the recombinant virions competed for the same or similar receptor-binding sites on the cell surface of human glioma cells. Furthermore, preferential homing of these virions was shown in xenograft glioma mouse model following intravascular delivery. Taken together, these results validated the hypothesis that HSV-1 binding to cells can be redirected to human gliomas through the incorporation of MG11 peptide sequence to the virions.

Enhancing legal preparedness for the prevention and control of infectious diseases: experience from severe acute respiratory syndrome in Hong Kong.

The use of legislation as a health protection tool forms an important and distinct aspect in the arena of public health. A review of Hong Kong's infectious disease legislation was conducted with a view to updating the legal framework for the prevention of infectious diseases, in order to strengthen the capacity of law to support strategy in the control of infectious diseases. This article shares Hong Kong's experience in reforming its public health legislation to: (1) update terminology and re-organize provisions in accordance with modern public health disease control principles and control mechanisms for disease; (2) enhance responsiveness for better preparedness and flexibility in handling emergent infections; (3) ensure appropriate checks and balances to coercive powers; and (4) introduce emergency powers for the handling of public health emergencies.

HSV-1 amplicon viral vector-mediated gene transfer to human bone marrow-derived mesenchymal stem cells.

Human bone marrow-derived mesenchymal stem cells (BM-hMSCs) are nonhematopoietic stem cells that have the potential to differentiate into adipocytes, osteocytes and chondrocytes. Because of its propensity to migrate to the sites of injury and the ability to expand them rapidly, BM-hMSCs have been exploited as potential gene transfer vehicles to deliver therapeutic genes. Herein, we evaluated the feasibility of employing herpes simplex virus type I (HSV-1) amplicon viral vector as a gene delivery vector to BM-hMSCs. High transduction efficiencies were consistently observed in different isolates of BM-hMSCs following infection with HSV-1 amplicon viral vectors. Furthermore, we demonstrated that transduction with HSV-1 amplicon viral vector did not alter the intrinsic properties of the BM-hMSCs. The morphology and cellular proliferation of the transduced BM-hMSCs were not altered. Chromosomal stability, as confirmed by karyotyping and soft agar colony assays, of the transduced BM-hMSCs was not affected. Similarly, transduction with HSV-1 amplicon viral vectors has no effect on the pluripotent differentiation potential and the tumor tropism of BM-hMSCs. Taken together, these results demonstrated that BM-hMSCs could be transduced efficiently by HSV-1 amplicon viral vector in an 'inert' manner and thus enable strategies to express potential therapeutic genes in BM-hMSCs.

Apixaban, an oral, direct and highly selective factor Xa inhibitor: in vitro, antithrombotic and antihemostatic studies.

BACKGROUND: Apixaban is an oral, direct and highly selective factor Xa (FXa) inhibitor in late-stage clinical development for the prevention and treatment of thromboembolic diseases. OBJECTIVE: We evaluated the in vitro properties of apixaban and its in vivo activities in rabbit models of thrombosis and hemostasis. METHODS: Studies were conducted in arteriovenous-shunt thrombosis (AVST), venous thrombosis (VT), electrically mediated carotid arterial thrombosis (ECAT) and cuticle bleeding time (BT) models. RESULTS: In vitro, apixaban is potent and selective, with a K(i) of 0.08 nm for human FXa. It exhibited species difference in FXa inhibition [FXa K(i) (nm): 0.16, rabbit; 1.3, rat; 1.7, dog] and anticoagulation [EC(2x) (microm, concentration required to double the prothrombin time): 3.6, human; 2.3, rabbit; 7.9, rat; 6.7, dog]. Apixaban at 10 microm did not alter human and rabbit platelet aggregation to ADP, gamma-thrombin, and collagen. In vivo, the values for antithrombotic ED(50) (dose that reduced thrombus weight or increased blood flow by 50% of the control) in AVST, VT and ECAT and the values for BT ED(3x) (dose that increased BT by 3-fold) were 0.27 +/- 0.03, 0.11 +/- 0.03, 0.07 +/- 0.02 and > 3 mg kg(-1) h(-1) i.v. for apixaban, 0.05 +/- 0.01, 0.05 +/- 0.01, 0.27 +/- 0.08 and > 3 mg kg(-1) h(-1) i.v. for the indirect FXa inhibitor fondaparinux, and 0.53 +/- 0.04, 0.27 +/- 0.01, 0.08 +/- 0.01 and 0.70 +/- 0.07 mg kg(-1) day(-1) p.o. for the oral anticoagulant warfarin, respectively. CONCLUSIONS: In summary, apixaban was effective in the prevention of experimental thrombosis at doses that preserve hemostasis in rabbits.

Nanosized bioceramic particles could function as efficient gene delivery vehicles with target specificity for the spleen.

We have compared the ability of several nanosized bioceramic particles including negatively charged silica (SiO(2)), neutrally charged hydroxyapatite (HA) and positively charged zirconia (ZrO(2)) nanoparticles as non-viral vectors for efficient in vivo gene delivery. A mixture of highly monodispersed aqueous suspension of HA or SiO(2) nanoparticles, coated with protamine sulfate (PS), complexed efficiently with plasmid DNA and significantly enhanced transgene expression in vitro. In comparison, ZrO(2) nanoparticles gave poor transfection efficiency under similar conditions tested. It was also determined that, under the same conditions, PS-SiO(2)-DNA, but not PS-HA-DNA-nanoplexes, were able to mediate efficient transgene expression in vitro in the presence of 50% serum. Intraperitoneal injections of PS-SiO(2)-luciferase DNA nanoplexes targeted the highest level of transgene expression in the spleen of recipient mice that lasted for more than 48 h. Injection of PS-SiO(2)-pNGVL-hFLex-MUC-1 nanoplexes was able to mediate the production of Flt-3L in the sera of recipient mice. Simultaneously, the production of Flt-3L was accompanied by the stimulation of IL-2 and interferon-gamma (IFN-gamma). Most importantly, the injection of PS-SiO(2)-pNGVL-hFLex-MUC-1 nanoplexes could mount potent anti-tumour specific immune responses that led to the subsequent regression of parental tumor cells containing the muc-1 determinant.

Targeting proliferating tumor cells via the transcriptional control of therapeutic genes.

We have previously reported the construction of a cell cycle-regulated HSV-1 amplicon vector (denoted as pC8-36) that confers luciferase reporter gene activities dependent on cellular divisions. However, luciferase reporter gene is well known for its relatively high sensitivity, thus, it is crucial to evaluate the therapeutic efficacy of a transcriptional targeted vector. In this report, we have engineered the FasL and FADD genes into pC8-36 and demonstrated their efficacy for the treatment of human gliomas in vitro and in vivo. Using trypan blue dye exclusion and TUNEL assay, FasL expression mediated by pC8-36 was shown to induce a significantly higher percentage of cell death in proliferating cells than those observed in the G(1)-arrested cells. The observed cell killing effect correlated well with the level of FasL protein expression when analyzed by ELISA assay. Furthermore, the incorporation of both FasL and FADD into pC8-36 resulted in the enhancement of apoptosis in the target glioma cells both in vitro and in vivo. Targeting proliferating tumor cells via the transcriptional control of therapeutic genes could potentially improve the safety and efficacy of cancer gene therapy, and thus would allow the development of strategies for more effective anticancer therapies.

Adolescent admissions to a tertiary paediatric hospital: a dynamic pattern.

INTRODUCTION: Adolescent inpatient facilities emerged in Australia in the 1980s to cater for an increasing number of young people with chronic illness and disability. Yet, there is minimal published data on the number of young people admitted to hospital within these units, their unit of admission, length of stay or reason for admission. A 12-year audit of adolescents admitted to a tertiary hospital with a dedicated adolescent unit and adolescent medicine programme in Victoria, Australia, was conducted to review the pattern of hospitalisation in young people in order to provide data to assist healthcare policy and planning agendas. MATERIALS AND METHODS: Admissions to the Royal Children's Hospital in Victoria, Australia, of adolescents aged 10 years and above were reviewed over a 12-year period from 1990 to 2001. We identified the annual number of adolescents admitted, the proportion of adolescents admitted to the Adolescent Inpatient Unit (ward) and annual admissions under the Adolescent Medicine Unit (department). RESULTS: Adolescents now constitute nearly 30% of all admissions at this children's hospital. Over this period, admissions to the Adolescent Inpatient Unit have nearly doubled and annual admissions under the Adolescent Medicine Unit rose from 38 to 288. The majority of adolescents were admitted under specialty medical and surgical units. CONCLUSIONS: The knowledge that nearly one in three admissions to this tertiary children's hospital is over 10 years old should help promote the development of planning and policy agendas that better balance both health and developmental priorities in this age group.

Delayed presentation of an ingested foreign body causing gastric perforation.

Ingested foreign bodies may lead to perforation of the gastrointestinal tract. We present a case of a 14-month-old boy who presented with an unusual abdominal mass secondary to ingesting a foreign body 4 months previously. Abdominal computerized tomography scan was valuable in making this diagnosis.

Potential of gene therapy for brain tumors.

Brain tumors comprise a broad spectrum of biological and clinical entities making it unlikely for any single therapeutic approach to be universally applicable. In particular, malignant glioblastoma multiforme have defied all current therapeutic modalities. Gene therapy offers the potential to augment current neurosurgical, radiation and drug treatments with little increase in morbidity. Many therapeutic transgenes have shown efficacy in experimental models, including generation of toxic compounds, enzymatic activation of pro-drugs, expression of tumor suppressor or apoptotic proteins, inhibition of angiogenesis and enhancement of immune responses to tumor antigens. Vectors have been used as gene delivery vehicles and as cytotoxic agents in their own right by selective replication and lysis of tumor cells, thereby also generating vectors on-site. Brain tumors appear to offer some "Achilles' heels" in that they are usually contained within the brain and represent a unique dividing cell population there. However, the heterogeneous and invasive characteristics of these tumor cells, as well as sequestration of tumor antigens within a relatively immune privileged location present serious problems for effective therapy. This review will focus on current transgene/vector strategies, including novel therapeutic genes, combinational therapies and new delivery modalities, the latter of which appears to be the rate limiting factor for gene therapy of brain tumors in humans.

Discovery of 1-[3-(aminomethyl)phenyl]-N-3-fluoro-2'-(methylsulfonyl)-[1,1'-biphenyl]-4-yl]-3-(trifluoromethyl)-1H-pyrazole-5-carboxamide (DPC423), a highly potent, selective, and orally bioavailable inhibitor of blood coagulation factor Xa.

Factor Xa (fXa) plays a critical role in the coagulation cascade, serving as the point of convergence of the intrinsic and extrinsic pathways. Together with nonenzymatic cofactor Va and Ca2+ on the phospholipid surface of platelets or endothelial cells, factor Xa forms the prothrombinase complex, which is responsible for the proteolysis of prothrombin to catalytically active thrombin. Thrombin, in turn, catalyzes the cleavage of fibrinogen to fibrin, thus initiating a process that ultimately leads to clot formation. Recently, we reported on a series of isoxazoline and isoxazole monobasic noncovalent inhibitors of factor Xa which show good potency in animal models of thrombosis. In this paper, we wish to report on the optimization of the heterocyclic core, which ultimately led to the discovery of a novel pyrazole SN429 (2b; fXa K(i) = 13 pM). We also report on our efforts to improve the oral bioavailability and pharmacokinetic profile of this series while maintaining subnanomolar potency and in vitro selectivity. This was achieved by replacing the highly basic benzamidine P1 with a less basic benzylamine moiety. Further optimization of the pyrazole core substitution and the biphenyl P4 culminated in the discovery of DPC423 (17h), a highly potent, selective, and orally active factor Xa inhibitor which was chosen for clinical development.

Expression of p19INK4d, CDK4, CDK6 in glioblastoma multiforme.

Deregulation of the G1/S checkpoint is a frequent event in the development of glioblastoma multiforme (GBM). Previous studies have shown more than 50% of primary GBM tumours contain either complete loss of the p16INK4a locus or amplification of the CDK4 gene. Moreover, many heterozygosity studies have shown deletion on human chromosome 19p13.2, where the p19INK4d gene has been localized. We examined the expression of p19INK4d and its two CDK substrates in a series of glioma-derived cell lines and tumours. No gene rearrangement or deletion was observed in the p19INK4d gene in these cell lines; however, expression of CDK4 and CDK6 was elevated relative to matched normal brain tissue in eight of 18 GBM tumours (44%). Furthermore, CDK6 expression level was increased in 12/14 glioblastomas, but undetectable in tumour samples of a previous lower grade tumour from the same patient. These data attest to the functional importance of both CDK4 and CDK6 in astrocytic tumourigenesis, particularly during the later stages of tumour progression.