Effect of cordycepin on Hantaan virus 76-118 infection of primary human embryonic pulmonary fibroblasts--characterization of apoptotic effects

The cDNA microarray technique was used to study gene epression in human embryonic pulmonary fibroblasts (HEPF) infected with Hantaan virus (HTNV) under the influence of cordycepin (Cor), an inhibitor of post-transcriptional pre-mRNA polyadenylation. Four apoptotic genes, the insulin-like growth factor binding protein 1, NFkB inhibitor alpha, caspase-3 and NFkB1 were up-regulated in both infected and uninfected Cor-treated cells and two cell cycle-associated genes, CDC-like kinase and beta-induced transforming growth factor were up-regulated in Cor-untreated cells but down-regulated in Cor-treated cells. Cell morphology examination, quantitative RT-PCR, and immunofluorescence (IF) test suggested that following the Cor treatment the HTNV infection took place, but late viral gene expression was slightly reduced. Three parameters, namely caspase-3 activity, annexin V binding, and cell cycle were used to detect apoptosis. The results suggested that the induction of apoptosis in HEPF by HTNV started at 6 hrs post infection (p.i.). Following the Cor treatment, however, the caspase-3 activity began to increase at 24 hrs p.i. Thus it is suggested that inhibition of de novo late viral protein synthesis by Cor changes the apoptosis pathway and cell cycle by delaying caspase-3 gene expression and by up/down-regulating of expression of other apoptotic and cell cycle-associated genes. This implicates that HTNV can induce apoptosis in HEPF even without de novo viral protein synthesis and with a reduced and slowed viral maturation.

Demonstration of different modes of cell death upon herpes simplex virus 1 infection in different types of oral cells

The effects of Herpes simplex virus 1 (HSV-1) infection on five different types of oral cancerous cells (neck metastasis of gingival carcinoma (GNM) cells and tongue squamous cells of carcinoma (TSCCa) and non-cancerous cells (buccal mucosal fibroblasts (BF), gingival fibroblasts (GF), oral submucosal fibrosis cells (OSF)) and one type of non-oral cancerous cells (KB cells) were investigated. In HSV-1-infected cells the cell viability, CPE, viral antigens accumulation, caspase-3 activity, annexin V binding and DNA fragmentation were estimated. Three different forms or pathways of cell death were considered: apoptosis (the presence or rise of caspase-3 activity, DNA fragmentation and annexin V binding), slow cell death (the presence or rise of DNA fragmentation, the absence or decline of caspase-3 activity and annexin V binding), and necrosis (the absence of decline of caspase-3 activity, DNA fragmentation and annexin V binding). The viability of all cell types, except for KB cells, was reduced by the infection. CPE and viral antigens data demonstrated that all six types of cells could be infected with HSV-1. Upon HSV-1 infection there occurred (i) a classical apoptosis in GF cells, (ii) apoptosis in the early phase of infection and necrosis in the late phase of infection in GNM and TSCCa cells, (iii) slow cell death followed by necrosis in BF and OSF cells (however, these cells showed a different type of CPE), (iv) a classical slow cell death in KB cells. It is hypothesized that HSV-1 infection has a potential to induce several distinct pathways leading to cell death or several forms of cell death. Moreover, more than one pathway may be involved in the death of particular cell type. As HSV-1 was demonstrated to infect different oral and non-oral cells and cause different pathways or forms of cell death, the safety of using HSV-1 as a vector for gene therapy should be re-considered.

Embryotrophic factor-3 from human oviductal cells enhances proliferation, suppresses apoptosis and stimulates the expression of the β1 subunit of sodium–potassium ATPase in mouse embryos

BACKGROUND

Embrytrophic factor-3 (ETF-3) from human oviductal cells enhanced the development of mouse preimplantation embryos. This report studied the embryotrophic mechanisms of the molecule.

METHODS AND RESULTS

Mouse embryos were incubated with ETF-3 for 24 h at different stages of development. ETF-3 treatment between 96 and 120 h post-HCG increased the cell count of blastocysts, whilst treatment between 72 and 96 h post-HCG enhanced the expansion and hatching of the blastocysts. ETF-3 increased the cell number of the embryos by suppressing apoptosis and increasing proliferation as determined by TUNEL and bromodeoxyuridine uptake assays, respectively. Real-time quantitative PCR showed that the in vivo developed and ETF-3-treated blastocysts had a significantly higher mRNA copy number of Na/K-ATPase-beta1, but not of hepsin, than that of blastocysts cultured in medium alone. The former gene was associated with cavitation of blastocysts while the latter was related to hatching of blastocyst. The beneficial effect of ETF-3 on blastocyst hatching was also seen when ETF-3-supplemented commercially available sequential culture medium for human embryo culture was used to culture mouse embryos.

CONCLUSIONS

ETF-3 improves embryo development by enhancing proliferation, suppressing apoptosis and stimulating expression of genes related to blastocyst cavitation. Supplementating human embryo culture medium with ETF-3 may improve the success rate in clinical assisted reproduction.

Peritonsillar infections: local experience

INTRODUCTION

The disease pattern and management of peritonsillar infections in Singapore General Hospital are studied. Other objectives are to determine if a seasonal variation exists and to examine the role of routine bacterial cultures and interval tonsillectomy.

METHODS

This is a retrospective review of the management and outcome of patients with peritonsillar infections who were admitted acutely to Singapore General Hospital over a three-year period.

RESULTS

Of 185 patients studied, 151 (81.6 percent) had peritonsillar abscess or quinsy and 34 (18.4 percent) had peritonsillar cellulitis. There were 139 males and 46 females, with a racial predisposition among Malays (p value is less than 0.0005). There may be a seasonal variation with a bi-annual trend, though no correlation with upper respiration tract infections was noted. Treatment consisted mainly of incision and drainage (66 percent) or needle aspiration (34 percent). No significant difference in the length of stay was noted in patients receiving penicillin alone, penicillin with metronidazole, or broad-spectrum antibiotics (p value is equal to 0.062). Fourteen (7.6 percent) patients had recurrences, all of which occurred after the first month. Two patients (1 percent) had bilateral quinsy.

CONCLUSION

Peritonsillar infections remain a common admitting diagnosis to the Otolaryngology department. A single episode of infection should no longer be an indication for tonsillectomy as the incidence of recurrence is low.

Climate, traffic-related air pollutants and allergic rhinitis prevalence in middle-school children in Taiwan

The prevalence of allergic rhinitis, a common respiratory disorder, may be rapidly increasing. Epidemiological studies, however, indicate little about its association with climatic factors and air pollution. The relationship between traffic-related air pollutants and allergic rhinitis in middle-school students was therefore investigated. In a nationwide survey of middle-school students in Taiwan conducted in 1995/1996, the lifetime prevalence of physician-diagnosed allergic rhinitis and typical symptoms of allergic rhinitis were compared with air-monitoring station data on temperature, relative humidity, sulphur dioxide (SO2), nitrogen oxides (NOx), ozone (O3), carbon monoxide (CO) and particulate matter with a 50% cut-off aerodynamic diameter of 10 microm (PM10). A total of 331,686 nonsmoking children attended schools located within 2 km of 55 stations. Mean (range) annual exposures were: CO 853 (381-1,610) parts per billion (ppb), NOx 35.1 (10.2-72.4) ppb, SO2 7.57 (0.88-21.2) ppb, PM10 69.2 (40.1-116.2) microg x m(-3), O3 21.3 (12.4-34.1) ppb, temperature 22.9 (19.6-25.1) degrees C, and relative humidity 76.2 (64.8-86.2)%. The prevalence of physician-diagnosed allergic rhinitis was 28.6 and 19.5% in males and females, respectively, with prevalence of questionnaire-determined allergic rhinitis 42.4 and 34.0%. After adjustment for age, parental education and history of atopic eczema, physician-diagnosed allergic rhinitis was found to be associated with higher nonsummer (September-May) warmth and traffic-related air pollutants, including CO, NOx and O3. Questionnaire-determined allergic rhinitis correlated only with traffic-related air pollutants. Nonsummer warmth and traffic-related air pollution, probably mediated through exposure to common allergens such as dust mites, are possible risk factors for allergic rhinitis in middle-school-aged children.

Embryotrophic factor-3 from human oviductal cells affects the messenger RNA expression of mouse blastocyst

Our previous results showed that embryotrophic factor-3 (ETF-3) from human oviductal cells increased the size and hatching rate of mouse blastocysts in vitro. The present study investigated the production of ETF-3 by an immortalized human oviductal cell line (OE-E6/E7) and the effects of ETF-3 on the mRNA expression of mouse embryos. The ETF-3 was purified from primary oviductal cell conditioned media using sequential liquid chromatographic systems, and antiserum against ETF-3 was raised. The ETF-3-supplemented Chatot-Ziomek-Bavister medium was used to culture Day 1 MF1 x BALB/c mouse embryos for 4 days. The ETF-3 treatment significantly enhanced the mouse embryo blastulation and hatching rate. The antiserum, at concentrations of 0.03-3%, abolished the embryotrophic effect of ETF-3. Positive ETF-3 immunoreactivity was detected in the primary oviductal cells, OE-E6/E7, and blastocysts derived from ETF-3 treatment. Vero cells (African Green Monkey kidney cell line), fibroblasts, and embryos cultured in control medium did not possess ETF-3 immunoreactivity. The mRNA expression patterns of the treated embryos were studied at the blastocyst stage by mRNA differential display reverse transcription-polymerase chain reaction (DDRT-PCR). The DDRT-PCR showed that some of the mRNAs were differentially expressed after ETF-3 treatment. Twelve of the differentially expressed mRNAs that had high homology with cDNA sequences in the GenBank were selected for further characterization. The differential expression of seven of these mRNAs (ezrin, heat shock 70-kDa protein, cytochrome c oxidase subunit VIIa-L precursor, proteinase-activated receptor 2, eukaryotic translation initiation factor 2beta, cullin 1, and proliferating cell nuclear antigen) was confirmed by semiquantitative RT-PCR. In conclusion, immortalized oviductal cells produce ETF-3, which influences mRNA expression of mouse blastocyst.

The proteins of synaptic vesicle membranes are affected during ageing of rat brain

Low molecular weight GTP-binding proteins are molecular switches that are believed to play pivotal roles in cell growth, differentiation, cytoskeletal organization, and vesicular trafficking. Rab proteins are key players in the regulation of vesicular transport, while Rho family members control actin-dependent cell functions, i.e. the regulation of cytoskeletal organization in response to extracelluar growth factors and in dendritic neuron development. In this study, we have examined the regulation of small GTP-binding proteins that are implicated in neurosecretion and differentiation of neuron during ageing processes. Comparison of small GTP-binding proteins from the synaptosome and crude synaptic vesicles (LP2 membranes) of 2 months and 20 months old rat brain respectively showed no difference in the level of Rab family proteins (Rab3A and Rab5A). However, Rho family proteins such as RhoA and Cdc42 were elevated in LP2 membranes of the aged brain. The dissociation of Rab3A by Ca2+/calmodulin (CaM) from SV membranes was not changed during aging. Ca2+/CaM stimulated phosphorylation of the 22 and 55-kDa proteins in SV membranes from the aged rat brain, and inhibited phosporylation of 30-kDa proteins. GTPgammaS inhibited phosphorylation of the 100-kDa proteins and stimulated phosphorylation of the 70 kDa in LP2 membranes from both the young and aged rat brains, whereas GDPbetaS caused just the opposite reaction. These results suggest that protein phosphorylation and regulation of Rho family GTPases in rat brain appears to be altered during ageing processes.

Formation of protoberberine-type alkaloids by the tubers of somatic embryo-derived plants of Corydalis yanhusuo

The effects of 0.5 - 5 mg/l abscisic acid [ABA], 0.5 - 10 mg/l (2RS,3RS)-1-(4-chlorophenyl)-4,4-dimethyl-2-(1,2,4-triazol-1-yl)pentan-3-ol [paclobutrazol] and 0.5 - 2 mg/l alpha-cyclopropyl-alpha-(4-methoxyphenyl)-5-pyrimidinemethanol [ancymidol], 0.5 - 5 mg/l gibberellic acid [GA(3)] and 15 - 100 mg/l polyethylene glycol [PEG] 4000 supplemented in half-strength Murashige and Skoog's (MS) medium on the production of the two major protoberberine-type alkaloids (D,L-tetrahydropalmatine and D-corydaline) by the tubers of somatic embryo-derived plants of Corydalis yanhusuo were examined. Somatic embryo derived plants were also maintained for 6 months on half-strength MS medium containing 0.1 mg/l GA(3) or 0.5 mg/l paclobutrazol. The alkaloid contents were determined by high performance liquid chromatography (HPLC). The analysis revealed that the contents of D,L-tetrahydropalmatine and D-corydaline in the tubers of somatic embryo-derived plants were higher than the marketed crude drug and varied with growth regulator/PEG-4000 treatment and the age of the plant.

Image display for collision avoidance of radiation therapy: treatment planning

Patient treatment in a medical linear accelerator is characterized by many angular and translational movements of the gantry and couch. The direction and orientation of each treatment beam is specified by a set of gantry, turntable, and collimator angles. It is possible that some selected treatment field configurations will result in gantry/couch or gantry/patient collisions that remain undetected during the treatment planning process. In this work, a digital camera has been used to record all the workable gantry/ patient set-up images, and a Windows programming language is used to edit and display these images on a personal computer for the treatment planner to screen the treatment plans. These graphical displays enable the planner to be aware of any potential collision hazards by an actual visualization of each selected gantry/turntable or gantry/patient angle configuration.

Construction of single-chain interleukin-12 DNA plasmid to treat airway hyperresponsiveness in an animal model of asthma

Allergic asthma is strongly associated with the airway inflammation caused by the dysregulated production of cytokines secreted by the allergen-specific type-2 T helper (Th2) cells. Interleukin (IL)-12 is a heterodimeric cytokine, which strongly promotes the differentiation of naive CD4(+) T cells to the type-1 T helper (Th1) phenotype and suppresses the expression of Th2 cytokines. Therefore, immunotherapy with IL-12 has been suggested as a possible therapy for asthma. In previous studies, we developed a murine model of airway inflammation based on the purified, house dust-mite allergen Der p 1 (Dermatophagodies pteronyssinus) as a clinically relevant allergen. We hypothesized that the expression of IL-12 in the airway may represent an effective therapy for allergic airway diseases. In this study, we investigate whether the local transfer of the IL-12 gene to respiratory tissues modifies allergic inflammation and airway hyper-responsiveness (AHR) in our disease model. To enhance the in vivo delivery of the IL-12 gene, we expressed the murine single-chain IL-12 protein from a nonviral vector to which the two IL-12 subunits (p35 and p40) were linked by a 14- to 18-amino-acid linker. One of these single-chain IL-12s, containing an 18 amino-acid polypeptide linker, was stably expressed and had a high level of biological activity comparable to that of native IL-12 in vitro. In mice with Der p 1-induced asthma, the local administration of this IL-12 fusion gene into the lungs significantly prevented the development of AHR, abrogated airway eosinophilia, and inhibited type-2 cytokine production. These findings indicate that the local transfer of the single-chain IL-12 gene is effective in modulating pulmonary allergic responses and may be a convenient method for future applications of DNA vaccination.

Observation of a (6)(LambdaLambda)He double hypernucleus

A double-hyperfragment event has been found in a hybrid-emulsion experiment. It is identified uniquely as the sequential decay of ( 6)(LambdaLambda)He emitted from a Xi(-) hyperon nuclear capture at rest. The mass of ( 6)(LambdaLambda)He and the Lambda-Lambda interaction energy DeltaB(LambdaLambda) have been measured for the first time devoid of the ambiguities due to the possibilities of excited states. The value of DeltaB(LambdaLambda) is 1.01+/-0.20(+0.18)(-0.11) MeV. This demonstrates that the Lambda-Lambda interaction is weakly attractive.

Bactericidal activity of citrate against Gram-positive cocci

AIMS

Coagulase-negative staphylococci (CNS) are now important nosocomial pathogens and are usually resistant to multiple antibiotics. Citrate is an alternative antimicrobial product which has been used as a preservative.

METHODS AND RESULTS

In this pilot study the bactericidal activity of Na citrate against 10 isolates of CNS and 6 other gram-positive pathogens was examined and compared with that of Na lactate.

CONCLUSIONS

All staphylococci tested were susceptible (> or = 2 log(10) killing) to citrate at 6.25-25 mg ml(-1). Na lactate showed only modest killing at 50 or 100 mg ml(-1).

SIGNIFICANCE AND IMPACT OF THE STUDY

Citrate may warrant broader evaluation as an antimicrobial additive such as in topical agents.

Bone brittleness varies with genetic background in A/J and C57BL/6J inbred mice

The contribution of genetic and environmental factors to variations in bone quality are understood poorly. We tested whether bone brittleness varies with genetic background using the A/J and C57BL/6J inbred mouse strains. Whole bone four-point bending tests revealed a 70% decrease in postyield deflection of A/J femurs compared with C57BL/6J, indicating that A/J femurs failed in a significantly more brittle manner. Cyclic loading studies indicated that A/J femurs accumulated damage differently than C57BL/6J femurs, consistent with their increased brittleness. Differences in matrix composition also were observed between the two mouse strains. A/J femurs had a 4.5% increase in ash content and an 11.8% decrease in collagen content. Interestingly, a reciprocal relationship was observed between femoral geometry and material stiffness; this relationship may have contributed to the brittle phenotype of A/J femurs. A/J femurs are more slender than those of C57BL/6J femurs; however, their 47% smaller moment of inertia appeared to be compensated by an increased tissue stiffness at the expense of altered tissue damageability. Importantly, these differences in whole bone mechanical properties between A/J and C57BL/6J femurs could not have been predicted from bone mass or density measures alone. The results indicated that bone brittleness is a genetically influenced trait and that it is associated with genetically determined differences in whole bone architecture, bone matrix composition, and mechanisms of cyclical damage accumulation.

Ammonium ions induce inactivation of Kir2.1 potassium channels expressed in Xenopus oocytes

1. The decay of inward currents was studied using the giant patch-clamp technique and a cloned inward rectifier K(+) channel, Kir2.1, expressed in Xenopus oocytes. 2. In inside-out patches, inward currents carried by NH4(+) or Tl(+) decayed over time. When the voltage was more negative, the degree and rate of decay were greater. The rate of NH4(+)-induced decay saturated at a symmetrical [NH4(+)] of approximately 100 mM. The decay rate was slow (2.6 x 10(3) M(-1) s(-1)) at -140 mV with 10 mM [NH4(+)]. 3. Upon a 10 degrees C increase in temperature, the single-channel NH4(+) current amplitude increased by a factor of 1.57, whereas the NH4(+)-induced decay rate increased by a factor of 2.76. In the R148Y Kir2.1 mutant (tyrosine 148 is at the external pore mouth), NH4(+)-induced inactivation was no longer observed. 4. NH4(+) single-channel currents revealed one open and one closed state. The entry rate into the closed state was voltage dependent whereas the exit rate from the closed state was not. An increase of internal [NH4(+)] not only decreased the entry rate into but also elevated the exit rate from the closed state, consistent with the occupancy model modified from the foot-in-the-door model of gating. 5. These results suggest that the decay of NH4(+) current is unlikely to be due to a simple bimolecular reaction leading to channel block. We propose that NH4(+) binding to Kir2.1 channels induces a conformational change followed by channel closure. 6. The decay induced by permeant ions other than K(+) may serve as a secondary selectivity filter, such that K(+) is the preferred permeant ion for Kir2.1 channels.

Overexpression of macrophage colony-stimulating factor receptor on microglial cells induces an inflammatory response

Microglia are important in the inflammatory response in Alzheimer's disease (AD). We showed previously that macrophage colony-stimulating factor receptor (M-CSFR), encoded by the c-fms protooncogene, is overexpressed on microglia surrounding amyloid beta (Abeta) deposits in the APP(V717F) mouse model for AD. The M-CSFR is also increased on microglia after experimental brain injury and in AD. To determine the relevance of these findings, we transiently expressed M-CSFR on murine BV-2 and human SV-A3 microglial cell lines using an SV40-promoted c-fms construct. M-CSFR overexpression resulted in microglial proliferation and increased expression of inducible nitric-oxide synthase, the proinflammatory cytokines interleukin-1alpha, macrophage inflammatory protein 1-alpha, and interleukin-6 and of macrophage colony-stimulating factor (M-CSF) itself. Antibody neutralization of M-CSF showed that the M-CSFR-induced proinflammatory response was dependent on M-CSF in the culture media. By using a co-culture of c-fms-transfected murine microglia and rat organotypic hippocampal slices and a species-specific real time reverse transcriptase-polymerase chain reaction assay and enzyme-linked immunosorbent assay, we showed that M-CSFR overexpression on exogenous microglia induced expression of interleukin-1alpha by the organotypic culture. These results show that increased M-CSFR expression induces microglial proliferation, cytokine expression, and a paracrine inflammatory response, suggesting that in APP(V717F) mice increased M-CSFR on microglia could be an important factor in Abeta-induced inflammatory response.

Establishment of a consistent L929 bioassay system for TNF-alpha quantitation to evaluate the effect of lipopolysaccharide, phytomitogens and cytodifferentiation agents on cytotoxicity of TNF-alpha secreted by adherent human mononuclear cells

TUMOR necrosis factor-alpha (TNF-alpha) plays an important role in the pathogenesis of rheumatoid arthritis. The present study was to evaluate the effects of lipopolysaccharide (LPS), phytomitogens and cytodifferentiation agents on cytotoxicity of TNF-alpha secreted by adherent human mononuclear cells (AMC). TNF-alpha cytotoxicity in LPS-treated, phytomitogen-treated, and cytodifferentiation agent-treated AMC supernatants were analyzed by the L929 bioassay system. Our results showed that LPS could induce homogeneous TNF-alpha production by AMC whereas, in addition to TNF-alpha, phytomitogens could also induce other TNF-like factors. Neither methotrexate, retinoic acid nor sodium butyrate can inhibit TNF-alpha cytotoxicity, while hexamethylene bisacetamide could not only inhibit TNF-alpha cytotoxicity but also TNF-alpha inducing ability of LPS to AMC.

Observation of a fast-formed absorption grating and a slowly formed phase grating in undeveloped dichromated gelatin

Real-time diffraction efficiency is measured during hologram formation in undeveloped dichromated gelatin (DCG) film. The main features of real-time diffraction efficiency of undeveloped DCG reveal double peaks with increasing exposure time. Adopting the grating translation technique, we show that the first peak originates from the absorption grating and that the latter is related to the phase grating. To explain such complicated hologram-formation dynamics, we present a phenomenological model for mixed gratings associated with photoinduced refractive-index changes and absorption changes. We have compared the model results with the experimental results, which show good agreement.

Establishment and characterization of an immortalized human oviductal cell line

Human oviductal cells stimulate embryo development in vitro partly by the production of embryotrophic glycoproteins. The identity of these glycoproteins is not yet known mainly because oviductal samples are limited and that the cultured parental oviductal cells cannot produce sufficient amount of embryotrophic factors for characterization. In this study, human oviductal epithelial cells (OE) were immortalized by HPV 16 E6/E7 open reading frame (ORF) by retroviral expression. The characteristics of this immortalized cell line (OE-E6/E7) were compared to the parental OE. HPV 16 E6/E7 DNA was found only in OE-E6/E7 but not in OE. Human oviduct-specific glycoprotein, estrogen receptors, and cytokeratin were found in both cell types. Both OE and OE-E6/E7 possessed telomerase activities but the former had much lower activity. OE-E6/E7 also produced glycoproteins with chromatographic behavior similar to the embryotrophic glycoproteins derived from OE. These results showed that OE-E6/E7 retained a number of characteristics of OE. The development of preimplantation mouse embryo was significantly better after coculture with OE-E6/E7 when compared to medium alone culture in term of blastulation rates (52% vs. 32%) and blastocyst diameter (113.0 +/- 2.07 microm vs. 83.9 +/- 5.23 microm). This immortalized cell line can be used as a continuous and stable in vitro system for the study of the oviductal embryotrophic activity. Mol. Reprod. Dev. 59: 400-409, 2001.

Highly sulfated forms of heparin sulfate are involved in japanese encephalitis virus infection

Japanese encephalitis virus (JEV) infects a broad range of cell types in vitro, though little is known about the initial events of JEV infection. In the present study, we found that highly sulfated glycosaminoglycans (GAGs) are involved in infection of both neurovirulent (RP-9) and attenuated (RP-2ms) JEV strains. Competition experiments using highly sulfated GAGs, heparin and dextran sulfate, demonstrated an inhibition of JEV's attachment and subsequent infection of BHK-21 cells. Treatment of target cells by a potent sulfation inhibitor, sodium chlorate, greatly reduced viral binding ability as well as infection, suggesting a critical role of GAGs' sulfation status on the cellular surface in JEV infection. This phenomenon was confirmed by the manifestation of a distinct binding efficiency of JEV to the wild-type CHO cell line and its mutants with defects in GAG biosynthesis. We also demonstrated the binding of JEV particles and virus envelope glycoprotein to immobilized heparin beads. Furthermore, the addition of heparin suppressed the cytopathic effects induced by JEV infection in cultured cells. Our results establish that the highly sulfated form of GAGs on cell surfaces plays a determining role in the early stage of in vitro JEV infection.

Development and deployment of a web-based physician order entry system

The computer-based Physician Order Entry System (POES) has been employed in many clinical institutes in Taiwan. Most of the POES systems are developed in the two-tier client-server architecture, and a large portion of the systems are constructed on a mainframe or even a single PC. The exponential growth of the Internet has had a tremendous impact on our society in recent years. In consideration of the future user interface and system architecture, we have developed a three-tier web-based Physician Order Entry System and successfully deployed it in the Wang-Fang Hospital in Taipei. The system is the first POES based on three-tier and World Wide Web (WWW) in Taiwan. The system provides the Subjective, Objective, Assessment, and Plan (SOAP) structure for the physician to enter subject, object, diagnoses, medicine dosage, treatment and laboratory test request, and prints out the prescription and necessary document. The doctor can also retrieve the patient's medical record on the system. One of the special characteristics of the system is its personalized design. The doctor can define their own diagnosis, medicine and treatment database and any combination of these to facilitate their clinical work. The system has been reviewed since February 1999. The result shows that the clinical procedure has become more efficient, and the chances of omission have been reduced. The system is very stable and the Open Database Connectivity (ODBC) database access did not show any delay in the network. Since we have incorporated many new web-programming techniques, the progress of the techniques will improve the system performance in the future.

Chemokine antagonist infusion promotes axonal sparing after spinal cord contusion injury in rat

Spinal cord injury produced by mechanical contusion causes the onset of acute and chronic degradative events. These include blood brain barrier disruption, edema, demyelination, axonal damage and neuronal cell death. Posttraumatic inflammation after spinal cord injury has been implicated in the secondary injury that ultimately leads to neurologic dysfunction. Studies after spinal cord contusion have shown expression of several chemokines early after injury and suggested a role for them in the ordered recruitment of inflammatory cells at the lesion site (McTigue et al. [1998] J. Neurosci. Res. 53:368-376; Lee et al., [2000] Neurochem Int). We have demonstrated previously that infusion of the broad-spectrum chemokine receptor antagonist (vMIPII) in the contused spinal cord initially attenuates leukocyte infiltration, suppresses' gliotic reaction and reduces neuronal damage after injury. These changes are accompanied by increased expression of bcl-2, the endogenous apoptosis inhibitor, and reduced neuronal apoptosis (Ghirnikar et al. [2000] J. Neurosci. Res. 59:63-73). We demonstrate that 2 and 4 weeks of vMIPII infusion in the contusion-injured spinal cord also results in decreased hematogenous infiltration and is accompanied by reduced axonal degeneration in the gray matter. Luxol fast blue and MBP immunoreactivity indicated reduced myelin breakdown in the dorsal and ventral funiculi. Increased neuronal survival in the ventral horns of vMIPII infused cords was seen along with increased bcl-2 staining in them. Immunohistochemical identification of fiber phenotypes showed increased presence of calcitonin gene related peptide, choline acetyl transferase and tyrosine hydroxylase positive fibers as well as increased GAP43 staining in treated cords. These results suggest that sustained reduction in posttraumatic cellular infiltration is beneficial for tissue survival. A preliminary report of this study has been published (Eng et al. [2000] J. Neurochem. 74(Suppl):S67B). In contrast to vMIPII, infusion of MCP-1 (9-76), a N-terminal analog of the MCP-1 chemokine showed only a modest reduction in cellular infiltration at 14 and 21 dpi without significant tissue survival after spinal cord contusion injury. Comparing data on tissue survival obtained with vMIPII and MCP-1 (9-76) further validate the importance of the use of broad-spectrum antagonists in the treatment of spinal cord injury. Controlling the inflammatory reaction and providing a growth permissive environment would enhance regeneration and ultimately lead to neurological recovery after spinal cord injury. J. Neurosci. Res. 64:582-589, 2001. Published 2001 Wiley-Liss, Inc.

Regulation of an endogenous locus using a panel of designed zinc finger proteins targeted to accessible chromatin regions. Activation of vascular endothelial growth factor A

We have mapped conserved regions of enhanced DNase I accessibility within the endogenous chromosomal locus of vascular endothelial growth factor A (VEGF-A). Synthetic zinc finger protein (ZFP) transcription factors were designed to target DNA sequences contained within the DNase I-hypersensitive regions. These ZFPs, when fused to either VP16 or p65 transcriptional activation domains, were able to activate expression of the VEGF-A gene as assayed by mRNA accumulation and VEGF-A protein secretion through a range exceeding that induced by hypoxic stress. Importantly, multiple splice variants of VEGF-A mRNA with defined physiological functions were induced by a single engineered ZFP transcription factor. We present evidence for an enhanced activation of VEGF-A gene transcription by ZFP transcription factors fused to VP16 and p65 targeted to two distinct chromosomal sites >500 base pairs upstream or downstream of the transcription start site. Our strategy provides a novel approach for dissecting the requirements for gene regulation at a distance without altering the DNA sequence of the endogenous target locus.

Cancer cells surviving hypoxia obtain hypoxia resistance and maintain anti-apoptotic potential under reoxygenation

In solid tumors hypoxia and reoxygenation may be important factors in secondary expansion after anti-cancer therapy. Our study examined the effect of hypoxia and reoxygenation on the apoptotic potential of cancer cells. Four experimental groups were studied using a human colorectal cancer cell line (HCT116) that is apoptosis-competent in conventional culture: (1) sham, cells grown under conventional conditions; (2) hypoxic, cells cultured in 95% N2 and 5% CO2 for 24 hr; (3) continued hypoxic, cells cultured for 48 hr; and (4) reoxygenation, cells grown in hypoxic conditions for 24 hr followed by another 24 hr under conventional conditions. Protein expression of p53, bcl-2 and PCNA were determined by immunohistochemistry and immunoblotting (p53), and viable cell growth rate was determined. Hypoxia for 24 hr induced significant up-regulation of p53 and bcl-2 expression, accompanied by significant decreases of cell growth rate and PCNA expression. Up-regulation of p53 and bcl-2 expression persisted with both continued hypoxia and reoxygenation, despite increased cell growth rate and PCNA expression. Cells escaping hypoxia acquired sustained resistance to apoptosis and proliferate despite an elevated p53 level, suggesting that p53 transfer to hypoxic solid tumor should be reevaluated as a cancer gene therapy approach.

Glial fibrillary acidic protein: GFAP-thirty-one years (1969-2000)

It is now well established that the glial fibrillary acidic protein (GFAP) is the principal 8-9 nm intermediate filament in mature astrocytes of the central nervous system (CNS). Over a decade ago, the value of GFAP as a prototype antigen in nervous tissue identification and as a standard marker for fundamental and applied research at an interdisciplinary level was recognized (Raine, 135). As a member of the cytoskeletal protein family, GFAP is thought to be important in modulating astrocyte motility and shape by providing structural stability to astrocytic processes. In the CNS of higher vertebrates, following injury, either as a result of trauma, disease, genetic disorders, or chemical insult, astrocytes become reactive and respond in a typical manner, termed astrogliosis. Astrogliosis is characterized by rapid synthesis of GFAP and is demonstrated by increase in protein content or by immunostaining with GFAP antibody. In addition to the major application of GFAP antisera for routine use in astrocyte identification in the CNS, the molecular cloning of the mouse gene in 1985 has opened a new and rich realm for GFAP studies. These include antisense, null mice, and numerous promoter studies. Studies showing that mice lacking GFAP are hypersensitive to cervical spinal cord injury caused by sudden acceleration of the head have provided more direct evidence for a structural role of GFAP. While the structural function of GFAP has become more acceptable, the use of GFAP antibodies and promoters continue to be valuable in studying CNS injury, disease, and development.

Crystallization and preliminary X-ray crystallographic analysis of thioesterase I from Escherichia coli

The Escherichia coli thioesterase I specifically catalyzes the deacylation of fatty acyl-CoA thioesters, especially those with long acyl groups (C(12)-C(18)). Single crystals of thioesterase I (E.C. 3. 1.2.2) from E. coli have been obtained using methoxypolyethylene glycol 5000 (PEG-MME 5K) as a precipitant at room temperature in 21 d. The crystals belong to the tetragonal space group P4(1)2(1)2 or its enantiomorph P4(3)2(1)2, with unit-cell parameters a = b = 50.85 (7), c = 171.5 (1) A. The crystals diffract to beyond 2.4 A resolution. There is one molecule of molecular weight 20.5 kDa in the asymmetric unit, with a solvent content of 55%.

Nasal colonization by methicillin-resistant coagulase-negative staphylococcus in community skilled nursing facility patients

BACKGROUND

Methicillin-resistant coagulase-negative staphylococci (MRCNS) are increasing nosocomial pathogens in acute care hospital patients. However, there is little information on the epidemiology of MRCNS in skilled nursing facilities (SNFs). We report a pilot survey of the prevalence of MRCNS colonization in SNF patients.

METHODS

Anterior nasal swabs were plated on oxacillin salt screening agar for selection of MRCNS. Suspected MRCNS were confirmed by coagulase and catalase tests and standard disc-diffusion antimicrobial susceptibility tests.

RESULTS

The overall prevalence of MRCNS was 40% for in-house continuing SNF patients, 49% for newly admitted patients, and 60% for SNF nursing personnel. The prevalence was 13% in a "control" group of nonmedical personnel. Forty-six percent of MRCNS were resistant to ciprofloxacin. The frequency of colonization with MRCNS increased over time. After an average 17 months of facility stay, 32% of noncarriers acquired MRCNS. High frequency of colonization was associated with greater disability.

CONCLUSION

Colonization with MRCNS is common among SNF patients, who can serve as a reservoir for transfer of such strains to acute care hospitals. Careful infection control practice, including judicious use of antibiotics with frequent handwashing, will remain critical policies for limiting spread of such strains.

Photocytotoxic and DNA damaging effect of temoporfin (mTHPC) and merocyanine 540 (MC540) on nasopharyngeal carcinoma cell

Photodynamic therapy (PDT) is a new approach to cancer treatment for a variety of malignant tumors. In this study, two clinical photosensitizers, Temoporfin (meta-tetra-hydroxyl-phenyl-chlorin; mTHPC) and merocyanine 540 (MC540), were selected to explore for their photocytotoxic and genotoxic effects on nasopharyngeal carcinoma cells (NPC/HK1 and CNE2). Results of tetrazolium reduction assay showed that 80% cell killing were achieved for both cell lines at 0.4 microg/ml mTHPC for 24 h incubation and then with 40 kJ/m2 light irradiation, whereas 40 microg/ml MC540 with 50 kJ/m2 light dosage was required to attain the same level of phototoxicity for NPC/HK1. On the contrary, NPC/CNE2 was quite resistant to MC540. Hence, mTHPC-mediated PDT exerted a more potent effect than MC540-mediated PDT, even though the molar extinction coefficient of the main absorption peak for MC540 is much higher than that of mTHPC. Dark cytotoxicity remained negligible for both sensitizers. Comet assay was used to evaluate the DNA strand break and potential genotoxic effect induced by mTHPC and MC540 on the NPC cells. No DNA strand break was detected in the absence of light, and under sublethal treatment (LD25) for either sensitizer-loaded cells. Confocal laser scanning microscopy showed that mTHPC and MC540 localized in the cytoplasm but not in the nucleus of the tumor cells, which provided evidence for undetectable DNA damage under dark and low photodynamic dose.

Cytokine chemokine expression in contused rat spinal cord

Spinal cord injury within the first few hours, is complicated by inflammatory mechanisms, including the influx of monocyte/macrophages as well as the activation of resident spinal microglia and astrocytes. Numerous studies have suggested that the initial infiltration of the hematogenous cells may be due to the secretion of cytokines and chemokines in the injured CNS. In order to elucidate which chemotactic factors may be expressed following traumatic spinal cord contusion, the presence of mRNA for a number of cytokines, chemokines and growth factors was examined in contused rat spinal cord by reverse transcriptase-polymerase chain reaction and immunohistochemistry. Spinal injury was accompanied by an increase in glial fibrillary acidic protein mRNA suggesting astrocyte activation and astrogliosis. TNFalpha message levels were upregulated as early as 1 h post injury and returned to baseline levels by 3 days post injury (DPI). By immunocytochemistry, staining for TNFalpha increased at 1 and 3 dpi and was predominantly diffuse in the necrotic tissue. The chemokines IP-10, MCP-1, and MIP-1alpha were also detected in the injured spinal cord. mRNA levels of IP-10 peaked around 6 h post injury and were upregulated up to 7 dpi. MCP-1 mRNA was detected at 1 h post injury and its levels returned to baseline by 14 dpi. An increase in MCP-1 staining was observed from 1 to 7 dpi. The staining was also diffuse in the necrotic tissue and also localized to cells near the site of injury. The presence of aFGF and bFGF was also detected in the injured spinal cord. mRNA for aFGF was detected at 0 time, increased at 6 h post injury, peaked at 3 days, and remained elevated up to 21 days. bFGF mRNA was initially detected at 1 h post injury, increased between 6 h and 3 days, declined thereafter and returned to baseline levels by 21 days.

Role of GRPergic neurons in secretin-evoked exocrine secretion in isolated rat pancreas

Effects of intrapancreatic gastrin-releasing peptide (GRP)-containing neurons on secretin-induced pancreatic secretion were investigated in the totally isolated perfused rat pancreas. Electrical field stimulation (EFS) increased secretin (12 pM)-induced pancreatic secretions of fluid and amylase. EFS induced a twofold increase in GRP concentration in portal effluent, which was completely inhibited by tetrodotoxin but not modified by atropine. An anti-GRP antiserum inhibited the EFS-enhanced secretin-induced secretions of fluid and amylase by 12 and 43%, respectively, whereas a simultaneous infusion of the antiserum and atropine completely abolished them. Exogenous GRP dose-dependently increased the secretin-induced pancreatic secretion with an additive effect on fluid secretion and a potentiating effect on amylase secretion, which was not affected by atropine. In conclusion, excitation by EFS of GRPergic neurons in the isolated rat pancreas results in the release of GRP, which exerts an additive effect on fluid secretion and a potentiating effect on amylase secretion stimulated by secretin. The release and action of GRP in the rat pancreas are independent of cholinergic tone.

Genotyping by restriction endonuclease analysis compared to phenotyping by antibiogram for typing methicillin-resistant Staphylococcus aureus strains colonizing patients in a nursing home

OBJECTIVES

To assist in defining patterns of methicillin-resistant Staphylococcus aureus (MRSA) colonization in a skilled nursing facility (SNF), we compared genotyping by field-inversion gel electrophoresis (FIGE) restriction endonuclease digestion analysis (REA) with phenotyping by antibiogram for defining strain relatedness among MRSA isolates from SNF patients.

DESIGN

Prospective screening culture surveillance for MRSA among patients in a community SNF.

METHODS

Nares and stool swab cultures were obtained from newly admitted patients and from all patients quarterly. MRSA were isolated by oxacillin screening agar. Antibiograms were determined by the disk-diffusion method, and genotyping was by FIGE REA.

RESULTS

It was shown that, among isolates with the same genotypes, many had different antibiograms; among isolates with the same antibiograms, many had different genotypes; and the discriminatory indices for isolates of MRSA by FIGE REA and by antibiogram were 0.56 and 0.78, respectively.

CONCLUSION

Our study demonstrated that, in patients from one SNF, genotyping by FIGE REA identified two prevalent REA DNA types, but with variability of antibiogram patterns within each DNA type; the antibiogram also identified prevalent patterns with variability of REA DNA type within each antibiogram pattern. The discriminatory index of antibiograms alone, or of genotypes alone as determined by FIGE REA, was poor for strains of MRSA isolated from the SNF patients in our study.

A novel cytotoxic C-methylated biflavone from the stem of Cephalotaxus wilsoniana

Bioassay-directed fractionation of an ethanolic extract of Cephalotaxus wilsoniana has resulted in the isolation of a novel C-methylated biflavone, taiwanhomoflavone-A (1). Its structure was elucidated on the basis of spectroscopic analysis. Taiwanhomoflavone-A is cytotoxic with ED50 values of 3.4, 1.0, 2.0 and 2.5 microg/ml, respectively, against KB epidermoid carcinoma of nasopharynx, COLO-205 colon carcinoma, Hepa-3B hepatoma, and Hela cervix tumor cells.

Chemokine antagonist infusion attenuates cellular infiltration following spinal cord contusion injury in rat

Spinal cord injury is accompanied by an initial inflammatory reaction followed by secondary injury that is caused, in part, by apoptosis. Recruitment of leukocytes from the blood compartment to the site of inflammation in the injured spinal cord has been attributed to locally generated chemotactic agents (cytokines and chemokines). In addition to upregulation in the message levels of a number of chemokines, we have found up-regulation in the message levels of several chemokine receptors following spinal cord contusion injury. To reduce the inflammatory response after spinal cord injury, we have blocked the interaction of chemokine receptors with their ligands using the vMIPII chemokine antagonist. Using a rat model of spinal cord contusion injury, we show that continuous infusion of the antagonist for up to 7 days results in a decrease in infiltrating hematogenous cells at the site of injury. Histological evaluation ofthe tissue showed fewer activated macrophages at the site of injury. Concomitantly, reduced neuronal loss and gliosis were observed in the antagonist infused spinal cord. In addition, increased expression of Bcl-2 gene, an endogenous inhibitor of apoptosis, was seen in the antagonist infused spinal cord at 7 days post injury. Morphologically, staining with the bisbenzamide dye Hoechst 33342 showed significantly more apoptotic bodies in the vehicle compared to antagonist infused spinal cord. Our data suggest that chemokine antagonist infusion post-injury results in limiting the inflammatory response following spinal cord contusion injury, thereby attenuating neuronal loss, possibly due to decreased apoptosis. These findings support the contention that disrupting chemokine interactions with their receptors may be an effective approach in reducing the secondary damage after spinal cord injury.

Inhibition of glucose uptake and suppression of glucose transporter 1 mRNA expression in L929 cells by tumour necrosis factor-alpha

Recombinant human tumour necrosis factor-alpha (rhTNF-alpha) arrested the growth and suppressed glucose uptake of mouse fibrosarcoma L929 cells in vitro. When the cells were treated with rhTNF-alpha for 24 hours, the mRNA level of glucose transporter 1 (GLUT 1), which is the only GLUT found to be present in L929 cells in our study, was suppressed in a dose-dependent manner. Since the growth of tumour cells depends mainly on glucose catabolism, our findings may indicate that rhTNF-alpha inhibits L929 cells growth by lowering the glucose transport through suppression of GLUT 1 mRNA expression in the cells.

Tuberous sclerosis with visceral organ involvement

This study is to determine the incidence of visceral organ involvement in tuberous sclerosis (TS). We reviewed 30 cases of TS diagnosed between 1987 to 1997. There were 17 males and 13 females, ages ranged from one day old to 17 years old. Among the 30 cases, 25 patients had seizures and skin manifestations; 24 had cerebral tubercles; 10 had heart involvement (9 rhabdomyoma, 1 dilated cardiomyopathy); 4 had kidney involvement (3 polycystic kidney disease, 1 renal hamartoma); and 3 had retinal astrocytic hamartoma. Based on our study, the most common visceral organs involved were the heart and kidney. Among the ten patients with cardiac rhabdomyoma, six were less than 1 year old (mean age 1.6 +/- 2.2 years old). One newborn presented with a cardiac mass diagnosed by prenatal sonography and another newborn, noted to have tachycardia after birth, underwent surgical intervention due to impending heart failure. Four patients had kidney abnormalities; three were less than 5 years old (mean age 5.2 +/- 5.2 years). During this 10 year period, there was no mortality seen among patients with visceral organ involvement. We suggest that clinicians treating patients with TS should not overlook the visceral organs, especially heart and kidney, which, if involved can have significant morbidity.

Culture positive tuberculous meningitis: clinical indicators of poor prognosis

Few studies have evaluated culture positive tuberculous meningitis (TBM) as a group. We evaluated certain clinical factors in culture positive TBM which could be associated with a poorer outcome. Out of 40 consecutive TBM patients seen over a period of 4 years in a tertiary referral hospital, 18 culture positive and non-human immunodeficiency virus (HIV) related cases were studied. The mean age was 37.9 +/- 14.9 years (range 9-63); five were males and 13 females. None had any associated active chronic medical illness. Patients (44.4%) started on antituberculous treatment within 24 h of admission. Treatment was initiated at a median time of 48 h upon admission in hospital. Univariate analysis revealed a significant correlation between hydrocephalus (P = 0.007) and poor morbidity and mortality. The other clinical factors were not statistically significant: age (P = 0.36): sex (P = 0.49); symptom duration (P = 0.69); BCG vaccination (P = 0.65); cerebral infarct (P = 0.63); extrameningeal spread (P = 1.00); steroids (P = 1.00); time to treatment (P = 0.94) and stage of disease (P = 0.11). Hydrocephalus was the only significant factor predisposing culture positive TBM patients to a poorer outcome. There was also a trend towards a poorer prognosis in those with advanced stage of the disease.

Enhanced cytotoxicity and suppression of glucose transport rate by combined treatment of recombinant human tumour necrosis factor-alpha and hyperthermia on L929 cells

Combined treatment with human recombinant TNF-alpha (rhTNF-alpha) and hyperthermia at 43 degrees C arrested the growth of mouse fibrosarcoma L929 cells in vitro. The cytotoxic effect was enhanced in combined treatment compared with that following administration of rhTNF-alpha or hyperthermia alone. When the cells were subjected to hyperthermia at 43 degrees C for 3 hours and then incubated with 0.4 ng/ml rhTNF-alpha at 37 degrees C for 24 hours, a statistically significant 65% decrease in the rate of cellular glucose uptake was observed. This suppressive effect was synergistic in terms of effect achieved by rhTNF-alpha or hyperthermia individually. Since the growth of tumour cells depends mainly on catabolism of glucose, our findings indicate that one manner by which combined rhTNF-alpha and hyperthermia treatment inhibits L929 cell growth may be by reducing the supply of glucose to the cells.

Deep vein thrombosis in elderly Hong Kong Chinese with hip fractures detected with compression ultrasound and Doppler imaging: incidence and effect of low molecular weight heparin

Seventy-eight patients of average age 78 years suffering from an unilateral non-pathological hip fracture underwent compression ultrasound and pulsed and colour Doppler examination of both legs. Twenty-three patients were randomly placed on low molecular weight heparin (LMWH). Twenty-nine (37%) suffered deep venous thrombosis (DVT). There was no statistically significant difference in the incidence of DVT between the control and LMWH groups, and the incidence of DVT in elderly Chinese patients after hip replacement for a hip fracture is similar to that in other studies in Caucasians. There were, however, some differences, namely the contiguous nature of the thrombi rather than focal segmental clots, and the absence of propagation or tail formation. Although the numbers are small, this could possibly represent a population difference. There was a significantly increased occurrence of DVTs on the operated side in both groups. Serial ultrasound examination supports evidence that DVTs occur in the 1st week postoperatively, but there were also a number of patients who developed DVTs in the 2nd week. There was no statistically significant difference in overall incidence of DVT between patients on prophylactic heparin and the control group. Patients on prophylactic heparin had no thigh DVTs in comparison to the control group. LMWH may thus be effective in preventing thigh DVTs and pulmonary emboli.

Administration of interleukin-12 prevents mite Der p 1 allergen-IgE antibody production and airway eosinophil infiltration in an animal model of airway inflammation

The aim of the present study was to examine the in vivo effect of interleukin (IL)-12 on a murine model of asthma induced by Dermatophagoides pteronyssinus-derived Der p 1 allergen. C57BL/6 mice immunized with Der p 1 allergen adsorbed to alum/pertussis toxin developed a T-helper type 2 (Th2)-dominant immune response characterized by the presence of IgE antibody, airway eosinophil infiltration and increased production of Th2 cytokine. Intraperitoneal injection of IL-12 (1 or 0.1 microg per day) for 5 days (day -1 to +3) simultaneously with each immunization, inhibited the production of IgE and IgG1 antigen-specific antibodies, whereas production of IgG2a was strongly enhanced. In addition, mice receiving both doses of IL-12 showed a strong inhibition of IL-5 but up-regulation of IFN-gamma production by spleen cells stimulated with antigen. Administration of IL-12 also prevented antigen-induced eosinophil infiltration into the bronchoalveolar area in a dose-dependent manner and the primary inflammatory mediator serotonin in bronchoalveolar lavage (BAL) fluids was also reduced significantly. Taken together, the data indicate that IL-12 has a potent immunomodulatory effect on house-dust-mite-induced allergic disorders and may be used as an efficient agent for immunotherapy.

Percutaneous vertebral biopsy through intact bone: a coaxial bone transgressing technique with 18 gauge needle

Advancement of radiologic technologies allows the detection of vertebral lesions at an earlier stage, thereby increasing the proportion of vertebral lesions that are surrounded by intact bone when they are detected. While biopsy guns are effective in obtaining good-quality tissue samples of osteolytic bone lesions, lesions that are covered by intact bone are not accessible with a biopsy gun. For percutaneous biopsy of osteolytic vertebral lesions, an intact-bone transgressing technique is described in which a simple, inexpensive and small-calibre (18-gauge) instrument is used to allow multiple passage of 20-gauge biopsy guns for effective tissue sampling. In this series consisting of metastatic and myeloproliferative lesions, the effectiveness and safety of this well-tolerated technique are demonstrated in thoracic and lumbar vertebrae.

Effects of intrapancreatic neuronal activation on cholecystokinin-induced exocrine secretion of isolated perfused rat pancreas

The role of intrapancreatic neurons in the action of cholecystokinin (CCK) on pancreatic exocrine secretion of the totally isolated, perfused rat pancreas was investigated. Intrapancreatic neurons were activated by applying electrical field stimulation (EFS) to the isolated pancreas for 45 min. When applying EFS, spontaneous pancreatic secretions of fluid and amylase increased until the second 15-min period of EFS and then decreased during the third 15-min period. Atropine (2 microM) notably reduced the EFS-evoked pancreatic secretions of fluid and amylase. The CCK-induced (10 pM) pancreatic secretions of fluid and amylase elevated further in the first 15-min period of EFS and then gradually resumed to the levels observed during application of CCK alone in the third 15-min period of EFS. However, the CCK-induced pancreatic secretions remained elevated even in the third 15-min period of EFS when an action of endogenous somatostatin was inhibited by cyclo-(7-aminoheptanonyl-Phe-d-Trp-Lys-Thr[BZL]) (10 nM) or pertussis toxin (200 ng/ml). EFS further elevated spontaneous exocrine secretion by the cysteamine-treated (300 mg/kg) pancreas, but this was markedly reduced, to normal levels, by infusing somatostatin (100 pM). EFS increased the numbers of immunoreactive somatostatin cells in the Langerhans' islets. The results indicate that intrapancreatic neuronal activation influences CCK-induced pancreatic secretions in a dual-phase pattern in the rat: an increase during the early phase and a decrease during the late phase. Endogenous somatostatin released from the islets appears to inhibit the enhancing effect of neuronal activation on CCK-induced pancreatic secretion. Of the intrapancreatic neurons, the cholinergic ones appear to predominate in EFS's effects on CCK-induced pancreatic secretion.

Excitatory and inhibitory amino acid levels in the cerebrospinal fluids of children with neurological disorders

Measurement of amino acid levels in the cerebrospinal fluid (CSF) of children with various neurological disorders was performed with high performance liquid chromatography (HPLC). Glutamate increased in patients with bacterial meningitis, aseptic meningitis and encephalitis. Aspartate increased in bacterial meningitis and seizure disorders. Glycine increased in both bacterial and aseptic meningitis. Taurine increased in bacterial meningitis and encephalitis. GABA, the main inhibitory amino acid, increased in encephalitis. Excitatory and inhibitory amino acids are richly distributed in brain tissue and are related to neuron activity. Changes in amino acid levels in the CSF may reflect the pathologic state and severity of brain insults, and may be useful in monitoring disease processes. Further study is necessary to determine whether CSF aminos acid levels have a role in practical clinical application.

Nasal colonization by Staphylococcus aureus in active, independent, community seniors

OBJECTIVE

to evaluate the prevalence of nasal colonization with Staphylococcus aureus (SA) in active, independent community seniors and old people in a nursing home.

DESIGN

cross-sectional brief questionnaire and screening culture of anterior nares specimens from 165 elders at a community centre and cross-sectional data from a recent survey in a nursing home.

RESULTS

the prevalence of SA colonization in community seniors (27%) was similar to that in the nursing home (29%). The proportion of SA isolates that were methicillin-resistant was much lower in the community seniors (2.3%) than in the nursing-home residents (31%). There was less antibiotic resistance in those living at home.

CONCLUSION

in community seniors the prevalence of SA colonization was similar to that in nursing-home residents, but the prevalence of methicillin-resistant SA was lower. Susceptibility patterns of antibiotics tested against the SA showed less resistance than isolates from nursing-home patients.

Effects of pulsed magnetic stimulation of GFAP levels in cultured astrocytes

The present study evaluates the physiological effects of magnetic stimulation on astrocyte cultures. Cell cultures were exposed to pulsed magnetic stimulation (10 Hz, 10 sec) at the following levels: 0.10 tesla (T; Group A); 0.21 T (Group B); 0.42 T (Group C); and 0.63 T (Group D). Glial fibrillary acidic protein (GFAP) levels from immunoblots, total protein concentrations, and cellular morphology were analyzed at 0, 1, 3, 5, 7, 13, and 20 days poststimulation. Significantly higher GFAP levels were observed in Group D at day 3 (P = 0.0114). The change was transient as the GFAP levels quickly returned to control levels by day 5. No other significant changes in GFAP levels were observed. In comparison to control protein levels at day 0, concentrations from Groups B, C, and D were significantly lower (P < 0.006), whereas at day 3, Groups C and D were significantly higher (P < 0.02). Differences in astrocyte morphology due to magnetic stimulation were not observed. This study demonstrated that high intensity magnetic stimulation for only 10 sec induced a transient biological response.

Selective uptake and sustained expression of AAV vectors following subcutaneous delivery

BACKGROUND

Recombinant adeno-associated viral (rAAV) vectors are capable of long-term expression of secreted and intracellular proteins following delivery to muscle, liver, and the central nervous system. In this study, we have evaluated subcutaneous injection of rAAV encoding a variety of transgenes as an alternative route of administration for the systemic delivery of therapeutic proteins.

METHODS

rAAV vectors encoding the human factor IX, human interferon-alpha 2a, murine erythropoietin (epo), and Escherichia coli lacZ genes were used for subcutaneous delivery into mature immunocompetent mice. Expression of factor IX and interferon in mouse serum was measured by ELISA. Expression of Epo was monitored by an increase in hemotocrit and by RIA. The tissue tropism of AAV transduction was determined by histochemistry following administration of the lacZ vector.

RESULTS

Long-term protein expression (at least one year) is demonstrated in the serum of immunocompetent mice following subcutaneous delivery of AAV vectors encoding the human factor IX and interferon genes. The murine epo gene delivered via this route resulted in levels of Epo that correlate with increased hematocrits of up to 90% for a duration of nine months. rAAV encoding the lacZ gene revealed that the panniculus carnosus, a skeletal muscle layer of the skin, was transduced upon subcutaneous administration.

CONCLUSIONS

This study shows that long-term expression of secreted proteins can be achieved using rAAV vectors injected subcutaneously as a single administration. The observation that the panniculus carnosus is the primary tissue transduced by rAAV illustrates the high tropism of rAAV for skeletal muscle.

Low-level colonization and infection with ciprofloxacin-resistant gram-negative bacilli in a skilled nursing facility

BACKGROUND

We report a 1-year surveillance study that evaluates colonization and infection with ciprofloxacin-resistant gram-negative bacilli (CR GNB) and the relation to quinolone use and other possible risk factors in a proprietary skilled nursing facility (SNF) with no history of outbreaks.

METHODS

Rectal swabs obtained quarterly were streaked on MacConkey agar with ciprofloxacin discs (5 microg) to screen for CR GNB and later were speciated and the antimicrobial susceptibilities were confirmed by standardized disc-diffusion tests.

RESULTS

The mean prevalence of CR GNB colonization was 2.6% (range 0.9% to 5.3%). The colonization frequency was higher in the last survey than it was in the first survey. CR GNB-colonized strains included Pseudomonas species (21%), but more than half were non-Pseudomonas enterics such as Acinetobacter baumannii (25%), Proteus mirabilis (17%), and Providencia stuartii (13%). None of the patients who had colonization with CR GNB had subsequent infections with the same species. Patients with colonization had more exposure to ciprofloxacin and they were more likely to have been recently admitted from an acute-care hospital and have decubitus ulcers. During the study period, of 336 patients surveyed, 98 (29%) patients developed suspected infections and cultures were done; the infection rate was 4.7 per 1000 patient days. Of these infected patients, 59 (60%) were infected by GNBs; the infection rate was 2.3 per 1000 patient days. Nineteen percent of the GNB infections were treated with a quinolone. (Overall, quinolones constituted about 17% of antibiotic usage in the SNF). Only 3 (5%) of the patients infected with GNB were infected with CR GNB, including Pseudomonas and Providenci a species. The CR GNB infections involved multiple sites, multiple organisms, and long length of stay in the SNF.

CONCLUSIONS

The findings indicate that in this community SNF, a low frequency of colonization or infection with CR GNB existed. Whether continued moderate use of quinolones will lead to increasing levels of CR GNB will require further study.