Improving interval estimation of binomial proportions

In this paper, we propose one new confidence interval for the binomial proportion; our interval is based on the Edgeworth expansion of a logit transformation of the sample proportion. We provide theoretical justification for the proposed interval and also compare the finite-sample performance of the proposed interval with the three best existing intervals-the Wilson interval, the Agresti-Coull interval and the Jeffreys interval-in terms of their coverage probabilities and expected lengths. We illustrate the proposed method in two real clinical studies.

Effect of inhaled formaldehyde on learning and memory of mice

In this study, we investigated the effect of inhaled formaldehyde on learning and memory capacity. After exposure to 0 (control), 1 and 3 mg/m(3) of gaseous formaldehyde respectively, the behavior of mice in a Morris water maze, the expression of NR1, NR2B mRNA and oxidative damage levels in mice brain were analyzed. The water maze performance, the activities of dismutase superoxide (SOD) and levels of glutathione (GSH) decreased significantly in 3 mg/m(3) group (P < 0.01, compared with control group); while malondialdehyde (MDA) contents and expression of NR1 and NR2B genes increased significantly after exposure to 3 mg/m(3) of gaseous formaldehyde (P < 0.05, <0.01, <0.01, compared with control group). These findings indicate that inhaled formaldehyde negatively affects learning and memory at 3 mg/m(3) of gaseous formaldehyde but not at lower levels. Oxidative stress-induced neuron damages in the brain may be the possible mechanism for these effects.

PRACTICAL IMPLICATIONS

This study indicates that inhaled formaldehyde starts to negatively affect learning and memory at a middle concentration of formaldehyde without interference of other indoor air pollutants. Oxidative damage, and the alteration of NMDA receptor expression, which were induced by formaldehyde inhalation, may be the possible mechanism for gaseous formaldehyde-induced neurotoxicity.

Continuous veno-venous haemofiltration attenuates myocardial mitochondrial respiratory chain complexes activity in porcine septic shock

Increasing evidence indicates that mitochondrial dysfunction plays an important role in modulating the development of septic shock. In the present study, we investigated whether continuous veno-venous haemofiltration (CVVH) with high-volume might improve myocardial mitochondrial dysfunction in a porcine model of peritonitis-induced septic shock. Sixteen male Landrace pigs weighing 31 +/- 5 kg were randomly assigned to normal control group (n = 4), peritonitis group (n = 6) and peritonitis plus CVVH group (n = 6). All animals were anaesthetised and mechanically ventilated. After baseline examinations, the peritonitis group and the peritonitis plus CVVH group underwent induction of peritonitis. One hour later, the animals in the peritonitis plus CVVH group received treatment with high-volume CVVH. Twelve hours after treatment, the animals were sacrificed. Animals in the peritonitis group were killed 13 hours after induction of peritonitis. Peritonitis challenge induced septic shock associated with increased blood lactate and high-volume CVVH improved lactate acidosis. Compared with the peritonitis group, cardiac output, stroke volume and mean arterial pressure were better maintained in peritonitis plus CVVH group. More importantly, high-volume CVVH improved myocardial mitochondrial complex I activity (0.22 +/- 0.03 vs. 0.15 +/- 0.04, P = 0.04). These results suggest that high-volume CVVH improves haemodynamics and heart dysfunction in septic shock and the improvement may be attributed to amelioration of myocardial mitochondrial dysfunction.

Spectral power distribution and quantum yields of Sm3+-doped heavy metal tellurite glass under the pumping of blue lighting emitting diode

Quantum yields for multichannel transition emissions have been determined in Sm3+-doped heavy metal tellurite glass under the pumping of blue lighting emitting diode for the first time. To achieve this goal, the necessary fluorescence spectra were measured and calibrated in an integrating sphere, which was connected to a CCD detector with a 400 microm-core optical fiber. The spectral power distribution of the sample under the blue LED pumping was derived from the measured spectra firstly, and then the quantum yields for the visible emissions of Sm3+ were calculated based on the distribution and the total quantum yields in visible region is 7.55%. For accurate measurements, integrating sphere method is proved to be a reliable and reproducible way to characterize luminescence and laser materials.

Exciton dissociation in organic light emitting diodes at the donor-acceptor interface

Experimental in situ photoluminescence and transient photovoltage results show that the interface formed by N, N{'}-Bis(naphthalene-1-yl)-N, N{'}-bis(phenyl) benzidine (NPB) and tris(8-hydroxyquinoline) aluminum (Alq{3}) acts as an exciton dissociation site. Because of this dissociation effect, excitons formed in NPB at or within a diffusion length of the interface tend to dissociate before they radiatively decay to generate blue light. This suggests that the action of the "hole-blocking layer" used in indium tin oxide\NPB\hole-blocking layer\Alq{3}\aluminium to promote blue light emission from the NPB is more "exciton dissociation inhibition" than "hole blocking."

Performance of silicon nanocrystal non-volatile memory devices under various programming mechanisms

Non-volatile memory devices based on silicon nanocrystal synthesized with very low energy Si+ implantation are fabricated. Memory performance under various programming mechanisms including Fowler-Nordheim (FN), drain-bias channel-hot-electron (DCHE), and source-bias channel-hot-electron (SCHE) has been investigated. It is observed that the DCHE yields the largest memory window among the three programming mechanisms. The DCHE and SCHE have similar endurance characteristics, but the SCHE has a longer retention time than the DCHE. Both the DCHE and SCHE have a larger memory window, a better endurance and a longer retention time as compared to the FN. Explanations to the phenomena are given.

Sensitive electrochemical enzyme immunoassay microdevice based on architecture of dual ring electrodes with a sensing cavity chamber

A novel electrochemical detection architecture was investigated for enzyme immunoassay sensors. Microchips with dual-ring working and counter electrodes, and a sensing cavity chamber were made on glass slides. The glass surface of the microchip was coated by 3-aminopropyltriethoxysilane (APTES). Goat IgG, as a example, was covalently captured on APTES-modified glass surfaces through glutaraldehyde (GA) as a cross-linker. Enzyme substrate, p-aminophenyl phosphate (PAPP) was prepared by electrolysis. The enzyme conversion from home-synthetic PAPP to p-aminophenol (PAP) was examined by differential pulse voltammetry (DPV). A competitive inhibition enzyme-linked immunosorbant assay (ELISA) was designed to test the system. Experimental results demonstrate that a detection limit of 118 fg/ml of goat IgG and a dynamic range of 118 fg/ml to 1.18 ng/ml, up to five orders of magnitude could be achieved. Due to its novel architecture design and electronic detection scheme, the method can be used to fabricate portable electrochemical ELISA lab-on-chip systems. The technology could have great potential in clinical diagnostic applications.

Changes in the expression of Fas on T lymphocytes after allogeneic fetal thymus transplantation in systemic lupus erytematosus mice

BACKGROUND

Systemic lupus erythematosus (SLE) is an autoimmune disorder that can produce inflammation in many organ systems. The rate of spontaneous apoptosis in lymphocytes from human SLE patients has been reported to be increased both in vivo and in vitro. Studies of fetal thymus transplantation in an autoimmune syndrome indicate that cellular immunity can be reconstituted and regulatory T cell functions can be normalized.

OBJECTIVES

The aim of this study was to assess changes in Fas expression on T lymphocytes following fetal thymus transplant.

METHODS

(B/CxB6) F1 (H-2d/h) female F1 mice were assigned to groups designated transplantation, normal, and control. Mice in the transplantation and control groups received parental BALB/c lymphocytes intravenously. Thirty days after injection of the lymphocytes, each F1 mouse in the transplantation group received a fetal thymus graft under the right renal capsule. Mice in the control group did not receive thymus transplant and mice in the normal group received neither parental lymphocytes nor a fetal thymus graft. All mice received cyclosporin A at 2 mg/kg daily for the first 12 days after transplantation or starting on the corresponding day. Thirty days after thymus transplantation, F1 mice were sacrificed and expression of Fas in peripheral blood lymphocytes was analyzed by flow cytometry.

RESULTS

The percentage of CD4Fas+ T lymphocytes was significantly increased in the control group and the transplantation group compared with the normal group. Corresponding significant differences were observed for CD8Fas+, CD4CD25Fas', and CD45RB(low)Fas+ T lymphocytes.

CONCLUSIONS

In this study, we found that fetal thymus transplantation had a significant effect on the expression of Fas by T cell subtypes in SLE mice.

Type II vanilloid receptor signaling system: one of the possible mechanisms for the rise in asthma cases

The prevalence of asthma keeps on increasing worldwide, especially in western societies over last 40 years. The mechanism of asthma is unclear. Recently, concern about indoor air pollution as a risk factor for asthma has been arisen. In present study, 25 Kun Ming male mice were placed in an air chamber containing respective formaldehyde (FA) concentration of 0, 0.5, 1.0, 3.0 mg/m3,and 3.0 mg/m3 with Capsazepine (CPZ, a specific antagonist of vanilloid receptor)-pretreatment in five testing groups (n=5 per group) for inhale experiments. The inhaled groups were exposed to gaseous FA for 6 hours each day in 10 successive days. After exposure, the concentrations of IL4 in blood serum and broncho alveolar lavage fluid (BALF) were measured. Experimental results showed that the IL4 level in serum was too low to be detected; and the concentrations of IL4 in BALF increased in a dose-dependent manner. However, for the CPZ-pretreated group the IL4 level in BALF decreased significantly (compared with 3.0 mg/m3 FA inhaled group, p<0.01). This paper describes experimental animal methods to probe IL4 level, an important indicator for IgE response. The studies in this paper indicated that gaseous FA might induce acquired atopy by type II VR1 signaling system. These findings suggested that indoor air pollutants such as FA might be key risk factors for the rise in asthma cases, and type II VR1 signaling system might be one of the mechanisms for the rise.

Treating chemical mechanical polishing (CMP) wastewater by electro-coagulation-flotation process with surfactant

The effect of surfactants on the treatment of chemical mechanical polishing (CMP) wastewater by electro-coagulation-flotation (ECF) process was studied. Two surfactants, cetyltrimethylammonium bromide (CTAB) and sodium dodecylsulfate (SDS) were employed in this study to compare the effect of cationic (CTAB) and anodic (SDS) surfactants on ECF. The cationic surfactant can enhance the removal of the turbidity, but anodic surfactant cannot. It can be explained by the hetero-coagulation theory. Moreover, the addition of CTAB in CMP wastewater can reduce the sludge volume and the flotation/sedimentation time in ECF process. The residual turbidity and dissolved silicon dropped with the increase of charge loading. No CTAB pollution problem exists after the ECF process.

Efficient probe immobilization on poly (dimethylsiloxane) for sensitive detection of proteins

Chemical surface modification methods were investigated to activate surface of poly-(dimethylsiloxane) (PDMS) for probe immobilization in enzyme-linked immunosorbent assay (ELISA). The investigations started from dramatization of PDMS surface with (3-aminopropyl)-triethoxysilane (APTES). Amino groups generated by APTES were either derived into carboxyl group by Succinic acid anhydride (SAA), then captured the protein through the heterobifunctional cross-linker, 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC), or directly reacted with homobifunctional cross-linker, glutaraldehyde (GA). Rabbit IgG, Goat IgG, Human IgA and Rat IgG were covalently immobilized on PDMS by both methods, and examined through well-organized competitive inhibition ELISA. The results demonstrated that both GA and EDC based methods had good covalent immobilization capability, and the EDC method had higher efficiency than the GA method. The competitive ELISA with probe immobilization through EDC had a detection limit of pg/ml level. The method was proved to be applicable for immobilization of different proteins. The topography of the immobilized protein properties was studied by atomic force microscope (AFM), demonstrating that the immobilization by GA had protein conglomeration, resulting in poorer uniformity and lower immobilization efficiency than EDC method. The possible reason is protein inter-molecule crossing linkage by the homobifunctional group of GA. Due to its simplicity, low cost, and high immobilization efficiency, EDC based immobilization method could provide great potential for making ELISA protein chips based on PDMS.

Impedance labelless detection-based polypyrrole protein biosensor

A simple and sensitive electrochemical immunosensor with impedance labelless detection and novel data processing method was investigated. One-step copolymerization was used to electrochemically deposit an antibody impregnated polypyrrole film on a glassy carbon electrode surface for the immunosensor. Impedance measurements provided a labelless or reporterless method to detect antibody (Ab)-antigen (Ag) interactions. Dimensionless analysis was employed to successfully process the measured impedance data. Since the method derived unit impedance change to eliminate or reduce the variation of the bulk electronic properties of Ab/polypyrrole films, the signal to noise ratio (S/N) was significantly improved for high sensitivity and specificity. Nonspecific binding effect was studied by array electrode chips and was found out that the polypyrrole electrode without antibody attachment had much stronger nonspecific binding effect than the Ab/polypyrrole electrode; incubation followed by thoroughly washing significantly reduced the nonspecific interference. 10 pg/ml detection limit and superior specificity were achieved by the method, demonstrating a highly sensitive labelless immunosensor in comparison with the detection limit of ng -microgram/ml for the reported polypyrrole based immunosensors. The electrochemical immunosensors presented in this paper, due to its simplicity, low cost, high sensitivity and superior specificity, could be an invaluable tool for clinical diagnostics and could have potential applications in drug discovery, environmental and food analysis.

Impact of Bond Order Loss on Surface and Nanosolid Mechanics

An analytical solution shows that a competition between bond order loss and the associated bond strength gain of the lower coordinated atoms near the edge of a surface dictates the mechanics of the surface and, hence, a nanosolid. Bond order loss lowers the activation energy for atomic dislocation, whereas bond strength gain enhances the energy density or mechanical strength in the region near the surface. Therefore, the surface is harder than the bulk interior at temperatures far below the melting point (T(m)), and the surface becomes softer at temperatures close to the surface T(m) that drops because of bond order loss. Matching predictions to measurements reveals that a transition happens to the Hall-Petch relationship for a nanosolid when the effect of bond order loss becomes dominant, and the critical size of the Hall-Petch transition depends intrinsically on the bond nature of the specimen and the ratio of T/T(m), where T is the temperature of operation.

Porous carbon composite/enzyme glucose microsensor

An enzyme glucose microsensor using a glucose oxidase-immobilized porous carbon/Teflon composite microelectrode was developed. The microsensor was fabricated by etching a platinum microelectrode (platinum, radius of 25 and 50 micrometers) in hot aqua regia to create a cavity at the tip and then packing a porous carbon/Teflon composite, which was made from acetylene black and Teflon emulsion, into the cavity. Nafion was impregnated into the inner surface of porous carbon/Teflon composite electrode following immobilization of Os(bpy)3+2/+3 as electron transfer mediators. The loading amount of Os(bpy)3+2/+3 in the Nafion/porous carbon/Teflon composite electrode was found to be 7.0x10(-8) mole cm(-2), which is much higher than that in polymer modified electrodes reported in literatures. The microsensor was further dipped overnight in buffer solution containing glucose oxidase for enzyme modification. With both glucose oxidase and mediators in the porous carbon/Teflon composite surface, the sensor performance was evaluated in buffer solutions containing different glucose concentrations and serum samples for glucose determination. The microsensor showed directly electrochemical glucose oxidation on the Os(bpy)3+2/+3 impregnated enzyme/porous carbon/Teflon composite surface with linear response over concentration range of 0-15 mM and Machaelis behavior. Reliability and reproducibility were conducted in serum samples and glucose buffer solution, and the results demonstrated there was no significant decrease of amperometric response in air-saturated solution for one month. The sensor demonstrated potential in clinical diagnostic applications.

Porous carbon composite/enzyme glucose microsensor

An enzyme glucose microsensor using a glucose oxidase-immobilized porous carbon/Teflon composite microelectrode was developed. The microsensor was fabricated by etching a platinum microelectrode (platinum, radius of 25 and 50 micrometers) in hot aqua regia to create a cavity at the tip and then packing a porous carbon/Teflon composite, which was made from acetylene black and Teflon emulsion, into the cavity. Nafion was impregnated into the inner surface of porous carbon/Teflon composite electrode following immobilization of Os(bpy)3+2/+3 as electron transfer mediators. The loading amount of Os(bpy)3+2/+3 in the Nafion/porous carbon/Teflon composite electrode was found to be 7.0x10(-8) mole cm(-2), which is much higher than that in polymer modified electrodes reported in literatures. The microsensor was further dipped overnight in buffer solution containing glucose oxidase for enzyme modification. With both glucose oxidase and mediators in the porous carbon/Teflon composite surface, the sensor performance was evaluated in buffer solutions containing different glucose concentrations and serum samples for glucose determination. The microsensor showed directly electrochemical glucose oxidation on the Os(bpy)3+2/+3 impregnated enzyme/porous carbon/Teflon composite surface with linear response over concentration range of 0-15 mM and Machaelis behavior. Reliability and reproducibility were conducted in serum samples and glucose buffer solution, and the results demonstrated there was no significant decrease of amperometric response in air-saturated solution for one month. The sensor demonstrated potential in clinical diagnostic applications.

Leiocyclocin C and D, two cyclopeptides from Goniothalamus leiocarpus

Two new cyclopeptides, leiocyclocin C (1) and D (2), were isolated from the seeds of Goniothalamus leiocarpus (Annonaceae). Their structures were determined as cyclo-(Gly1-Ser-Pro2-Tyr2-Gly2-Tyr1-Pro1-Pro3) and cyclo-(Gly1-Leu-Pro1-Gly2-Phe-Tyr-Pro2), respectively, by means of spectral and chemical methods.

Response heterogeneity of human macrophages to ATP is associated with P2X7 receptor expression but not to polymorphisms in the P2RX7 promoter

A region 2 kb upstream of exon 1 of the P2X7 gene was sequenced using DNA from nine healthy individuals who exhibited three different ATP response phenotypes (i.e. high, low and interferon gamma-inducible). Five single nucleotide polymorphisms were identified within the nine donor promoter sequences but none were associated with a specific ATP response phenotype. A P2X7 loss of function polymorphism (1513 in exon 13) was also screened for within donor DNA but no response associations were identified. ATP response phenotype was positively associated with P2X(7) receptor expression, as assessed by flow cytometry, but not with any identified receptor or promoter gene polymorphisms.

Non-clostridial gas gangrene caused by Klebsiella pneumoniae: a case report

A 45-y-old man was hospitalized due to pain and swelling of the right leg for 3 d. Bullae developed with gas formation involving multiple compartments of the entire limb 46 h later. Klebsiella pneumoniae was recovered from blood and surgical specimens. The patient died on Day 8 despite amputation and antibiotic therapy.

Atrophy of Müller glia and photoreceptor cells in chick retina misexpressing cNSCL2

PURPOSE

To investigate whether and how the basic helix-loop-helix (bHLH) gene cNSCL2 is involved in retinal development.

METHODS

cNSCL2, the chick homologue of human NSCL2, was isolated and sequenced. In situ hybridization was used to examine its spatial and temporal expression pattern in the retina. Replication-competent retrovirus RCAS was used to drive cNSCL2 misexpression in the developing chick retina, and the effect of the misexpression was analyzed.

RESULTS

Expression of cNSCL2 in the retina was restricted. Its mRNA was detected in amacrine and horizontal cells, but not in photoreceptor, bipolar, or ganglion cells. Retroviral-driven misexpression of cNSCL2 in the developing chick retina resulted in missing photoreceptor cells and gross deficits in the outer nuclear layer (ONL). These deficits were probably not because of decreased photoreceptor production, in that the ONL appeared normal in early developmental stages. TUNEL+ cells were detected in the ONL, indicating that photoreceptor cells underwent apoptosis in retinas misexpressing cNSCL2. Müller glial cells were far fewer in the experimental retina than in the control, indicating that cNSCL2 also caused Müller glia atrophy. The onset of Müller glia disappearance preceded that of photoreceptor degeneration.

CONCLUSIONS

Expression of cNSCL2 in the chick retina was restricted to amacrine and horizontal cells. Misexpression of cNSCL2 caused severe retinal degeneration, and photoreceptor cells and Müller glia were particularly affected.

A nonsense mutation is responsible for the RNA-negative phenotype in human citrullinaemia

Citrullinaemia is an inborn error of metabolism resulting from a deficiency of argininosuccinate synthetase. Previous studies of RNA of argininosuccinate synthetase of citrullinaemia patients using S1 nuclease analysis have identified a class of so-called RNA-negative alleles in which no stable mRNA can be detected. To investigate the nature of mutation responsible for such a phenotype, a compound heterozygous citrullinaemia carrying an RNA-negative allele and an allele with a 3' splice site mutation in intron 6 (IVS6-2A>G) was analysed. Using sequences of a DNA polymorphism and the IVS6-2A>G mutation as markers, approximately equal amounts of pre-mRNAs from allelic genes were detected suggesting that RNA-negative phenotype could not be the result of defect in transcription initiation. A C-to-T transition converting the CGA arginine codon at residue 279 to a TGA termination codon (R279X) was identified by cDNA sequencing. No accumulation of partially spliced pre-mRNAs containing introns immediately upstream and downstream of the nonsense mutation was observed. In addition, no mRNA species of abnormal size was detected when cDNA from the RNA-negative allele was analysed. Hence, there is no indication of nonsense-associated altered splicing (NAS). The most likely event responsible for the RNA-negative phenotype appears to be nonsense-mediated mRNA decay (NMD).

Transforming growth factor-beta(1) modifies fibroblast growth factor-2 production in type II cells

Transforming growth factor (TGF)-beta(1) is an inflammatory cytokine that plays multiple roles in pulmonary fibrosis. In vascular epithelium, it has been shown to regulate production and activity of fibroblast growth factor (FGF)-2, a potent type II cell mitogen in the lung. Such a relationship could have important consequences in prefibrotic change in the lung alveolus, where reepithelialization of alveolar surfaces is crucial. The goal of this study was to determine if FGF-2 production by alveolar type II cells is modulated by TGF-beta(1) or FGF-1, another type II cell mitogen. Isolated rat type II cells were exposed to 0 to 40 ng/mL of TGF-beta(1) or 0 to 500 ng/mL of FGF-1 in serum-free medium for 1 to 3 days. Using a specific immunoassay, significant increases in FGF-2 protein in type II cell lysates were achieved after 1 day of exposure to 100 ng/mL of FGF-1 and after 3 days of treatment with 8 ng/mL of TGF-beta(1). Similarly, transcripts for FGF-2 were dramatically increased with TGF-beta(1) or FGF-1, as were those for FGF receptor (FGFR)-1. These interactions were dramatically effected by the addition of heparin, a model sulfated extracellular matrix (ECM). Heparin as low as 0.01 mg/mL significantly downregulated expression of TGF-beta(1) and FGF-1-stimulated FGF-2 and FGFR-1. These results demonstrate important regulatory links between FGF-2, sulfated ECMs, and both TGF-beta(1) and FGF-1, which could contribute to the modulation of normal cell turnover, development, and repair processes attendant to fibrosis in the lung.

Clinical characteristics of emphysematous pyelonephritis

A total of 21 patients (20 women and one man) with emphysematous pyelonephritis (EPN), treated in the Kaohsiung Veterans General Hospital during the period from 1991 through 1999 were included in this study. All of the patients were diabetic. The most common symptoms or signs were fever/chills (80%) and costovertebral angle knocking pain (71%). Diagnosis was confirmed by the presence of gas in the parenchyma or paranephric space on plain X-ray of the abdomen or computed tomography. The left kidney (11 cases, 52%) was more frequently affected than the right one (nine cases, 43%), and both kidneys were involved in one case. Obstruction of the corresponding renoureteral unit was found in 19% of the patients, and renal or ureteral stone was found in 23% of the patients. One third of the patients had type I EPN, and two-thirds had type II EPN. Escherichia coli was the most commonly isolated organism, accounting for 61%, 76%, and 47% of isolates from blood, urine, and aspirated pus culture respectively. Prompt control of blood sugar was begun and intravenous antibiotics were given. Drainage was performed in 71% of the patients, and two persons required nephrectomy because of poor control of the infection or complications. Overall survival was 72%. Emphysematous pyelonephritis is a rare, life-threatening, suppurative infection of the renal parenchyma and perirenaL tissues. For successful management of EPN, appropriate medical treatment should be initiated, and immediate nephrectomy or drainage should not be delayed.

ATP-mediated killing of Mycobacterium bovis bacille Calmette-Guérin within human macrophages is calcium dependent and associated with the acidification of mycobacteria-containing phagosomes

We previously demonstrated that extracellular ATP stimulated macrophage death and mycobacterial killing within Mycobacterium bovis Bacille Calmette-Guérin (BCG)-infected human macrophages. ATP increases the cytosolic Ca(2+) concentration in macrophages by mobilizing intracellular Ca(2+) via G protein-coupled P2Y receptors, or promoting the influx of extracellular Ca(2+) via P2X purinoceptors. The relative contribution of these receptors and Ca(2+) sources to ATP-stimulated macrophage death and mycobacterial killing was investigated. We demonstrate that 1) ATP mobilizes Ca(2+) in UTP-desensitized macrophages (in Ca(2+)-free medium) and 2) UTP but not ATP fails to deplete the intracellular Ca(2+) store, suggesting that the pharmacological properties of ATP and UTP differ, and that a Ca(2+)-mobilizing P2Y purinoceptor in addition to the P2Y(2) subtype is expressed on human macrophages. ATP and the Ca(2+) ionophore, ionomycin, promoted macrophage death and BCG killing, but ionomycin-mediated macrophage death was inhibited whereas BCG killing was largely retained in Ca(2+)-free medium. Pretreatment of cells with thapsigargin (which depletes inositol (1,4,5)-trisphosphate-mobilizable intracellular stores) or 1,2-bis-(2-aminophenoxy)ethane-N, N, N',N'-tetraacetic acid acetoxymethyl ester (an intracellular Ca(2+) chelator) failed to inhibit ATP-stimulated macrophage death but blocked mycobacterial killing. Using the acidotropic molecular probe, 3-(2,4-dinitroanilino)-3'-amino-N-methyl dipropylamine, it was revealed that ATP stimulation promoted the acidification of BCG-containing phagosomes within human macrophages, and this effect was similarly dependent upon Ca(2+) mobilization from intracellular stores. We conclude that the cytotoxic and bactericidal effects of ATP can be uncoupled and that BCG killing is not the inevitable consequence of death of the host macrophage.

Transmission of human immunodeficiency virus through bone transplantation: a case report

Human immunodeficiency virus (HIV) can be transmitted through tissue or organ transplantation. Since 1988, eight cases of bone transplantation-associated HIV infection have been reported. We describe a 34-year-old woman with osteoarthritis, who was hospitalized in 1996 because of painful locomotion and deformity in the right knee. An old fracture of the femur and genu varum in the right knee was repaired by open reduction and internal fixation, with allogeneic bone transplantation for defect reconstruction. Five months later, she presented at another hospital with pain and swelling of the right thigh, where screening for HIV was positive. The transmission was tracked to a 50-year-old man with no history of HIV screening, from whom the femoral head was procured when he underwent a hip replacement for left femoral neck fracture. This is the first reported case of HIV infection through bone transplantation in Taiwan, and the preventable nature of this transmission should be underscored.