Deep-Learning-Enabled Computer-Aided Diagnosis in the Classification of Pancreatic Cystic Lesions on Confocal Laser Endomicroscopy

Accurate classification of pancreatic cystic lesions (PCLs) is important to facilitate proper treatment and to improve patient outcomes. We utilized the convolutional neural network (CNN) of VGG19 to develop a computer-aided diagnosis (CAD) system in the classification of subtypes of PCLs in endoscopic ultrasound-guided needle-based confocal laser endomicroscopy (nCLE). From a retrospectively collected 22,424 nCLE video frames (50 videos) as the training/validation set and 11,047 nCLE video frames (18 videos) as the test set, we developed and compared the diagnostic performance of three CNNs with distinct methods of designating the region of interest. The diagnostic accuracy for subtypes of PCLs by CNNs with manual, maximal rectangular, and U-Net algorithm-designated ROIs was 100%, 38.9%, and 66.7% on a per-video basis and 88.99%, 73.94%, and 76.12% on a per-frame basis, respectively. Our per-frame analysis suggested differential levels of diagnostic accuracy among the five subtypes of PCLs, where non-mucinous PCLs (serous cystic neoplasm: 93.11%, cystic neuroendocrine tumor: 84.31%, and pseudocyst: 98%) had higher diagnostic accuracy than mucinous PCLs (intraductal papillary mucinous neoplasm: 84.43% and mucinous cystic neoplasm: 86.1%). Our CNN demonstrated superior specificity compared to the state-of-the-art for the classification of mucinous PCLs (IPMN and MCN), with high specificity (94.3% and 92.8%, respectively) but low sensitivity (46% and 45.2%, respectively). This suggests the complimentary role of CNN-enabled CAD systems, especially for clinically suspected mucinous PCLs.

Miniaturization and image optimization of a full-color holographic display system using a vibrating light guide

In this study, a miniaturized full-color holographic reconstruction system that uses a single spatial light modulator to achieve full-color image reconstruction was developed. The reconstruction system uses a single light guide for light combination and is therefore less voluminous than conventional reconstruction systems. The experimental results demonstrated that the system had a full-color display, corrected light combination, and eliminated zero-order light. The vibrations of the light guide disrupted the temporal coherence of the laser beam, thus ensuring that the speckle in the reconstructed image was almost imperceptible to the human eye.

Dual heterogeneous structures lead to ultrahigh strength and uniform ductility in a Co-Cr-Ni medium-entropy alloy

Alloys with ultra-high strength and sufficient ductility are highly desired for modern engineering applications but difficult to develop. Here we report that, by a careful controlling alloy composition, thermomechanical process, and microstructural feature, a Co-Cr-Ni-based medium-entropy alloy (MEA) with a dual heterogeneous structure of both matrix and precipitates can be designed to provide an ultra-high tensile strength of 2.2 GPa and uniform elongation of 13% at ambient temperature, properties that are much improved over their counterparts without the heterogeneous structure. Electron microscopy characterizations reveal that the dual heterogeneous structures are composed of a heterogeneous matrix with both coarse grains (10∼30 μm) and ultra-fine grains (0.5∼2 μm), together with heterogeneous L1₂-structured nanoprecipitates ranging from several to hundreds of nanometers. The heterogeneous L1₂ nanoprecipitates are fully coherent with the matrix, minimizing the elastic misfit strain of interfaces, relieving the stress concentration during deformation, and playing an active role in enhanced ductility.

Improving both strength and ductility simultaneously in structural metals and alloys remains a challenge. Here, the authors design a heterogeneous structure in a Co-Cr-Ni alloy that results in ultrahigh strength and significant uniform elongation.

First trimester placental vascular indices and volume by three-dimensional ultrasound in pre-gravid overweight women

OBJECTIVES

To investigate changes of placental vascular indices and volume in pre-gravid overweight Chinese women during the first trimester using three-dimensional power Doppler ultrasound.

METHODS

This was a prospective observational study of the morphology of placentas in pre-gravid overweight (body mass index (BMI) ≥ 24 kg/m²) and non-overweight (BMI < 24 kg/m²) Chinese women during the first trimester of pregnancy. Data on placental vascular indices (vascularization index, flow index, and vascularization flow index (VFI)), placental volume, uterine artery pulsatility index (PI), and neonatal outcomes were obtained during the first trimester and analyzed. Linear regression analysis was used to evaluate confounding factors between BMI and ultrasound indices.

RESULTS

Of the 429 pregnant women enrolled, 68 (15.9%) were pre-gravid overweight. Placental VFI was significantly lower in the overweight group (p = 0.037). Conversely, placental volume was significantly larger in the overweight group (p = 0.044), and uterine artery PI was significantly higher in the overweight group (p = 0.021). After adjustments for confounding factors, there were still significant differences in placental VFI (unstandardized coefficient (B) -0.666, 95% confidence interval (CI) -1.306 - (-0.025)), placental volume (B 2.458, 95% CI 0.071-4.844), and uterine artery PI (B 0.152, 95% CI 0.030-0.274) between the two groups.

CONCLUSIONS

Placental vascular indices using three-dimensional power Doppler ultrasound can provide an insight into placental vascularization in pre-gravid overweight women in early pregnancy. Alterations in placental VFI, placental volume, and uterine artery PI occur during the first trimester in pre-gravid overweight women.

Econazole induces increases in free intracellular Ca2+ concentrations in human osteosarcoma cells

Econazole is an antifungal drug with different in vitro effects. However, econazole's effect on osteoblast like cells is unknown. In human MG63 osteosarcoma cells, the effect of econazole on intracellular Ca2+ concentrations ([Ca2+]i) was explored by using fura-2. At a concentration of 0.1 μM, econazole started to cause a rise in [Ca2+]i in a concentration-dependent manner. Econazole-induced [Ca2+]i rise was reduced by 74% by removal of extracellular Ca2+. The econazole-induced Ca2+ influx was mediated via a nimodipine-sensitive pathway. In Ca2+ free medium, thapsigargin, an inhibitor of the endoplasmic reticulum Ca2+ ATPase, caused a [Ca2+]i rise, after which the increasing effect of econazole on [Ca2+]i was abolished. Pretreatment of cells with econazole to deplete Ca2+ stores totally prevented thapsigargin from releasing Ca2+. U73122, an inhibitor of phospholipase C, abolished histamine (an inositol 1,4,5-trisphosphate dependent Ca2+ mobilizer)-induced, but not econazoleinduced, [Ca2+]i rise. Econazole inhibited 76% of thapsigargin-induced store-operated Ca2+ entry. These findings suggest that in MG63 osteosarcoma cells, econazole increases [Ca2+]i by stimulating Ca2+ influx and Ca2+ release from the endoplasmic reticulum via a phospholipase C-independent manner. In contrast, econazole acts as a potent blocker of store-operated Ca2+ entry.

Computer-aided diagnosis in endoscopy: a novel application toward automatic detection of abnormal lesions on magnifying narrow-band imaging endoscopy in the stomach

Gastric cancer is the fourth common cancer and the second major cause of cancer death worldwide. Early detection of gastric cancer by endoscopy surveillance is actively investigated to improve patient survival, especially using the newly developed magnifying narrow-band imaging endoscopy in the stomach. However, meticulous examination of the aforementioned images is both time and experience demanding and interpretation could be variable among different doctors, which hindered its widespread application. In this study, we developed a new image analysis system by adopting local binary pattern and vector quantization to perform pattern comparison between known training abnormal images and testing images of magnifying narrow band endoscopy images in the stomach. Our preliminary results demonstrated promising potential for automatically labeled region of interest for endoscopy doctors to focus on abnormal lesions for subsequent targeted biopsy, with the rates of recall 0.46-1.00 and precision 0.39-0.87.

Fast self-organizing feature map algorithm

We present an efficient approach to forming feature maps. The method involves three stages. In the first stage, we use the K-means algorithm to select N2 (i.e., the size of the feature map to be formed) cluster centers from a data set. Then a heuristic assignment strategy is employed to organize the N2 selected data points into an N x N neural array so as to form an initial feature map. If the initial map is not good enough, then it will be fine-tuned by the traditional Kohonen self-organizing feature map (SOM) algorithm under a fast cooling regime in the third stage. By our three-stage method, a topologically ordered feature map would be formed very quickly instead of requiring a huge amount of iterations to fine-tune the weights toward the density distribution of the data points, which usually happened in the conventional SOM algorithm. Three data sets are utilized to illustrate the proposed method.

Effect of phenethyl isothiocyanate on Ca2+ movement and viability in MDCK canine renal tubular cells

The effect of the natural compound phenethyl isothiocyanate (PEITC) on cytosolic Ca2+ concentrations ([Ca2+]i) and viability in MDCK renal cells is unknown. This study explored whether PEITC changed [Ca2+]i in MDCK cells using the Ca2+-sensitive fluorescent dye fura-2. PEITC at 200–700 μM increased [Ca2+]i in a concentration-dependent manner. The signal was reduced by removing extracellular Ca2+. PEITC-induced Ca2+ influx was inhibited by nifedipine, econazole, SK&F 96365 and protein kinase C modulators. In Ca2+-free medium, treatment with the endoplasmic reticulum Ca2+ pump inhibitor thapsigargin (TG) or 2,5-di- tert-butylhydroquinone (BHQ) inhibited PEITC-induced rise in [Ca2+]i. Incubation with PEITC also inhibited TG or BHQ-induced rise in [Ca2+]i. Inhibition of phospholipase C with U73122 abolished PEITC-induced rise in [Ca2+]i. At 15–75 μM, PEITC decreased viability. The cytotoxic effect of PEITC was enhanced by chelating cytosolic Ca2+ with 1,2-bis(2-aminophenoxy)ethane- N, N, N′, N′-tetraacetic acid/acetoxymethyl ester. Annexin V-FITC data suggest that 20 and 50 μM PEITC induced apoptosis. At 10 and 15 μM, PEITC did not increase reactive oxygen species (ROS) production. Together, in renal tubular cells, PEITC-induced rise in [Ca2+]i by inducing phospholipase C-dependent Ca2+ release from endoplasmic reticulum and Ca2+ entry via store-operated Ca2+ channels. PEITC induced apoptosis in a concentration-dependent, ROS/Ca2+-independent manner.

Biofilm detachment mechanisms in a liquid-fluidized bed

Bed fluidization offers the possibility of gaining the advantages of fixed-film biological processes without the disadvantage of pore clogging. However, the biofilm detachment rate, due to hydrodynamics and particle-to-particle attrition, is very poorly understood for fluidized-bed biofilm processes. In this work, a two-phase fluidized-bed biofilm was operated under a constant surface loading (0.09 mg total organic carbon/cm(2) day) and with a range of bed height (H), fluid velocities (U), and support-particle concentrations (C(p)). Direct measurements were made for the specific biofilm loss rate coefficient (b(s))and the total biofilm accumulation (X(f)L(f)). A hydrodynamic model allowed independent determination of the biofilm density (X(f)), biofilm thickness (L(f)), liquid shear stress (tau), and Reynolds number (Re). Multiple regression analysis of the results showed that increased particle-to-particle attrition, proportional to C(p) and increased turbulence, described by Re, caused the biofilms to be denser and thinner. The specific detachment rate coefficient (b(s)) increased as C(p) and Re increased. Almost all of the 6, values were larger than predicted by a previous model derived for smooth biofilms on a nonfluidized surface. Therefore, the turbulence and attrition of bed fluidization appear to be dominant detachment mechanisms.

Effect of thimerosal on Ca2+ movement and viability in human oral cancer cells

The effect of thimerosal on cytosolic free Ca2+ concentrations ([Ca2+]i ) in human oral cancer cells (OC2) is unclear. This study explored whether thimerosal changed basal [Ca2+]i levels in suspended OC2 cells using fura-2. Thimerosal at concentrations between 1and 50 μM increased [Ca2+]i in a concentration-dependent manner. The Ca2+ signal was reduced partly by removing extracellular Ca 2+. Thimerosal-induced Ca2+ influx was not blocked by L-type Ca2+ entry inhibitors and protein kinase C modulators (phorbol 12-myristate 13-acetate [PMA] and GF109203X). In Ca2+-free medium, 50 μM thimerosal failed to induce a [Ca2+]i rise after pretreatment with thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor). Inhibition of phospholipase C with U73122 did not change thimerosal-induced [Ca2+]i rises. At concentrations between 5 and 10 μM, thimerosal killed cells in a concentration-dependent manner. The cytotoxic effect of 8 μM thimerosal was potentiated by prechelating cytosolic Ca2+ with the Ca2+ chelator 1,2-bis(2-aminophenoxy)ethane-N,N,N′,N′-tetraacetate/acetomethyl (BAPTA/ AM). Flow cytometry data suggested that 1—7 μM thimerosal-induced apoptosis in a concentration-dependent manner. Collectively, in OC2 cells, thimerosal-induced [Ca2+]i rises by causing phospholipase C-independent Ca2+ release from the endoplasmic reticulum and Ca2+ influx through non—L-type Ca2+ channels. Thimerosal killed cells in a concentration-dependent manner through apoptosis.

Effect of Celecoxib on Ca2+Fluxes and Proliferation in MDCK Renal Tubular Cells

The effect of celecoxib on renal tubular cells is largely unexplored. In Madin Darby canine kidney (MDCK) cells, the effect of celecoxib on intracellular CaCa2+ concentration ([Ca2+]i) and proliferation was examined by using the Ca(2 +)-sensitive fluorescent dye fura-2 and the viability detecting fluorescent dye tetrazolium, respectively. Celecoxib (> or =1 micro M) caused an increase of [CaCa2+]i in a concentration-dependent manner. Celecoxib-induced [CaCa2+]i increase was partly reduced by removal of extracellular CaCa2+. Celecoxib-induced CaCa2+ influx was independently suggested by MnCa2+ influx-induced fura-2 fluorescence quench. In Ca(2 +)-free medium, thapsigargin, an inhibitor of the endoplasmic reticulum Ca(2 +)-ATPase, caused a monophasic [CaCa2+]i increase, after which celecoxib only induced a tiny [CaCa2+]i increase; conversely, pretreatment with celecoxib completely inhibited thapsigargin-induced [CaCa2+]i increases. U73122, an inhibitor of phospholipase C, abolished ATP (but not celecoxib)-induced [CaCa2+]i increases. Overnight incubation with 1 or 10 micro M celecoxib decreased cell viability by 80% and 100%, respectively. These data indicate that celecoxib evokes a [CaCa2+]i increase in renal tubular cells by stimulating both extracellular CaCa2+ influx and intracellular CaCa2+ release and is highly toxic to renal tubular cells in vitro.

Safrole-Induced Ca2+Mobilization and Cytotoxicity in Human PC3 Prostate Cancer Cells

The effect of the carcinogen safrole on intracellular Ca2+ mobilization and on viability of human PC3 prostate cancer cells was examined. Cytosolic free Ca2+ levels ([Ca2+]i) were measured by using fura-2 as a probe. Safrole at concentrations above 10 microM increased [Ca2+]i in a concentration-dependent manner with an EC50 value of 350 microM. The Ca2+ signal was reduced by more than half after removing extracellular Ca2+ but was unaffected by nifedipine, nicardipine, nimodipine, diltiazem, or verapamil. In Ca2+-free medium, after treatment with 650 microM safrole, 1 microM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor) failed to release Ca2+. Neither inhibition of phospholipase C with U73122 nor modulation of protein kinase C activity affected safrole-induced Ca2+ release. Overnight incubation with 0.65-65 microM safrole did not affect cell viability, but incubation with 325-625 microM safrole decreased viability. Collectively, the data suggest that in PC3 cells, safrole induced a [Ca2+]i increase by causing Ca2+ release from the endoplasmic reticulum in a phospholipase C- and protein kinase C-independent fashion, and by inducing Ca2+ influx. Safrole can decrease cell viability in a concentration-dependent manner.

Melittin-induced [Ca2+]i increases and subsequent death in canine renal tubular cells

The effect of melittin on cytosolic free Ca2+ concentration ([Ca2+]i) and viability is largely unknown. This study examined whether melittin alters Ca2+ levels and causes Ca2+-dependent cell death in Madin-Darby canine kidney (MDCK) cells. [Ca2+]i and cell death were measured using the fluorescent dyes fura-2 and WST-1 respectively. Melittin at concentrations above 0.5 μM increased [Ca2+]i in a concentration-dependent manner. The Ca2+ signal was reduced by 75% by removing extracellular Ca2+. The melittin-induced Ca2+ influx was also implicated by melittin-caused Mn2+ influx. After pretreatment with 1 μM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor), melittin-induced Ca2+ release was inhibited; and conversely, melittin pretreatment abolished thapsigargin-induced Ca2+ release. At concentrations of 0.5–20 μM, melittin killed cells in a concentration-dependent manner. The cytotoxic effect of 0.5 μM melittin was nearly completely reversed by prechelating cytosolic Ca2+ with BAPTA. Melittin at 0.5–2 μM caused apoptosis as assessed by flow cytometry of propidium iodide staining. Collectively, in MDCK cells, melittin induced a [Ca2+]i rise by causing Ca2+ release from endoplasmic reticulum and Ca2+ influx from extracellular space. Furthermore, melittin can cause Ca2+-dependent cytotoxicity in a concentration-dependent manner.

Coracoclavicular ligament reconstruction using a gracilis tendon graft for acute type-III acromioclavicular dislocation

PURPOSE

To review the functional and radiological results of patients after coracoclavicular ligament reconstruction.

METHODS

Five patients aged 21 to 50 (mean, 37) years with acute Rockwood type-III acromioclavicular dislocation underwent coracoclavicular ligament reconstruction with autogenous gracilis tendon grafts. Patients were either active in sports or heavy manual workers. Assessments on shoulder function (using the Constant score), wound size, pain (using a visual analogue scale), and reduction (using radiographs of both acromioclavicular joints) were made.

RESULTS

The mean follow-up period was 26 (range, 15-43) months; the mean time to return to work or sports was 14 (range, 12-20) weeks. The mean Constant score was 94 (range, 90-98). The mean donor-site scar size was 3 cm and the mean pain score was 0. No major complication or donor-site morbidity was noted. There was one subluxation.

CONCLUSION

Coracoclavicular ligament reconstruction using an autogenous gracilis tendon graft was safe in physically active patients having acute type-III acromioclavicular dislocation.

Effect of riluzole on Ca2+ movement and cytotoxicity in Madin-Darby canine kidney cells

Riluzole is a drug used in the treatment of amyotrophic lateral sclerosis; however, its in vitro action is unclear. In this study, the effect of riluzole on intracellular Ca2+ concentration ([Ca2+]i) in Madin-Darby canine kidney (MDCK) cells was investigated using the Ca2+ -sensitive fluorescent dye, fura-2. Riluzole (100-500 microM) caused a rapid and sustained increase of [Ca2+]i in a concentration-dependent manner (EC50 = 150 microM). Some 40 and 50% of this [Ca2+]i increase was prevented by the removal of extracellular Ca2+ and the addition of La3+, respectively, but was unchanged by dihydropyridines, verapamil and diltiazem. In Ca2+ -free medium, thapsigargin - an inhibitor of the endoplasmic reticulum (ER) Caz+ -ATPase--caused a monophasic [Ca2+]i increase, after which the increasing effect of riluzole on [Ca2+]i was attenuated by 70%; in addition, pre-treatment with riluzole abolished thapsigargin-induced [Ca2+]i increases. U73122, an inhibitor of phospholipase C (PLC), abolished ATP (but not riluzole)-induced [Ca2+]i increases. At concentrations of 250 and 500 microM, riluzole killed 40 and 95% cells, respectively. The cytotoxic effect of riluzole (250 microM) was unaltered by pre-chelating cytosolic Ca2+ with BAPTA. Collectively, in MDCK cells, riluzole rapidly increased [Ca2+]i by stimulating extracellular Ca2+ influx via an La3+ -sensitive pathway and intracellular Ca2+ release from the ER via, as yet, unidentified mechanisms. Furthermore, riluzole caused Ca2+ -unrelated cytotoxicity in a concentration-dependent manner.

Subacute human spinal cord contusion: few lymphocytes and many macrophages

STUDY DESIGN

Clinicopathological correlation of three cases of subacute cervical spinal cord contusions.

OBJECTIVE

To correlate the pathology of subacute cervical spinal cord injury (SCI) with imaging and clinical-functional studies, and to compare with findings from previous human SCI studies and animal models of SCI.

SETTING

Department of Pathology, SUNY-Upstate Medical University, Syracuse, NY, USA.

METHOD

Post mortem pathology report.

CASE REPORT/RESULTS

The clinical, radiological, and pathological findings of three cases of subacute spinal cord contusions are described in detail. The postinjury survival periods were 15, 20, and 60 days, respectively. Extensive microglia/macrophage infiltrations without significant lymphocytes are seen in all cases. Free radical injury as assessed by immunocytochemistry for 4-hydroxynonenal and nitrotyrosine showed a labeling pattern parallel to that of the macrophage distribution at 15 days, but no significant labeling in the injury sites at 20 and 60 days.

CONCLUSION

The present report, though limited in sample size, shows plenty of activated microglia/macrophages in human SCI up to 60 days postinjury. This observation not only confirms similar findings in previous studies, but also raises an intriguing question of potential interactions between these activated microglia/macrophages and the experimental therapy, proposed by some authors, of injecting exogenously activated macrophages to promote SCI repair. The small number of human SCI cases (in this as well as in most other single medical centers) available for detailed study illustrates the need for the establishment of a consortium of human SCI tissue banks.

Pressurized liquid extraction followed by high-performance liquid chromatography for determination of seven active compounds in Cortex Dictamni

A new method based on pressurized liquid extraction (PLE) followed by a sensitive and specific HPLC-DAD analysis is developed for determination of seven compounds in Cortex Dictamni. The operational parameters of PLE, such as extraction solvent, extraction temperature, extraction pressure, static extraction time, flush volume and extraction cycles were optimized, using the extraction efficiencies of dictamnine, obacunone and fraxinellone as targets. The optimized procedure employed MeOH as extraction solvent, 150 degrees C of extraction temperature, 1,500 psi extraction pressure, 5 min of static extraction time, 60% flush volume and the extraction recoveries of the three compounds were nearly to 100% for only one cycle. The following HPLC analysis was performed on a reversed-phase C(18) column with methanol-water as mobile phase in gradient manner, detected at 236 and 218 nm. The limits of detection (LOD) and limits of quantification (LOQ) of the seven compounds were in the range of 0.4-15.6 ng and 1.2-38.8 ng. This assay can be readily utilized as a quality control method for Cortex Dictamni and other related medicinal plants.

Effect of triethyltin on Ca2+ movement in Madin-Darby canine kidney cells

The effects of the environmental toxicant, triethyltin, on Ca2+ mobilization in Madin-Darby canine kidney (MDCK) cells have been examined. Triethyltin induced an increase in cytosolic free Ca2+ levels ([Ca2+]i) at concentrations larger than 2 microM in a concentration-dependent manner. Within 5 min, the [Ca2+]i signal was composed of a gradual rise and a sustained phase. The [Ca2+]i signal was partly reduced by removing extracellular Ca2+. In Ca(2+)-free medium, pretreatment with thapsigargin (1 microM), an endoplasmic reticulum Ca2+ pump inhibitor, reduced 50 microM triethyltin-induced [Ca2+]i increase by 80%. Conversely, pretreatment with triethyltin abolished thapsigargin-induced Ca2+ release. Pretreatment with U73122 (2 microM) to inhibit phospholipase C-coupled inositol 1,4,5-trisphosphate formations failed to alter 50 microM triethyltin-induced Ca2+ release. Incubation with triethyltin at a concentration (1 microM) that did not increase basal [Ca2+]i for 3 min did not alter ATP (10 microM)- and bradykinin (1 microM)-induced [Ca2+]i increases. Collectively, this study shows that triethyltin altered Ca2+ movement in renal tubular cells by releasing Ca2+ from multiple stores in an inositol 1,4,5-trisphosphate-independent manner, and by inducing Ca2+ influx.

Gradient match and side match fractal vector quantizers for images

In this paper, we propose gradient match fractal vector quantizers (GMFVQs) and side match fractal vector quantizers (SMFVQs), which are two classes of finite state fractal vector quantizers (FSFVQs), for the image coding framework. In our previous work, we proposed the noniterative fractal block coding (FBC) technique to improve the decoding speed and the coding performance for conventional FBC techniques. To reduce the number of bits for denoting the fractal code of the range block, the concepts of the gradient match vector quantizers (GMVQs) and the side match vector quantizers (SMVQs) are employed to the noniterative FBC technique. Unlike ordinary vector quantizers, the super codebooks in the proposed GMFVQs and SMFVQs are generated from the affine-transformed domain blocks in the noniterative FBC technique. The codewords in the state codebook are dynamically extracted from the super codebook with the side-match and gradient-match criteria. The redundancy in the affine-transformed domain blocks is greatly reduced and the compression ratio can be significantly increased. Our simulation results show that 15%-20% of the bit rates in the noniterative FBC technique are saved by using the proposed GMFVQs.

Mechanism underlying histamine-induced intracellular Ca2+ movement in PC3 human prostate cancer cells

The effect of histamine on intracellular free Ca2+ levels ([Ca2+]i) in PC3 human prostate cancer cells and the underlying mechanism were evaluated using fura-2 as a Ca2+ dye. Histamine at concentrations between 0.1 and 50 microM increased [Ca2+]i in a concentration-dependent manner with an EC50 value of 1 microM. The [Ca2+]i response comprised an initial rise and a slow decay, which returned to baseline within 3 min. Extracellular Ca2+ removal inhibited 50% of the [Ca2+]i signal. In the absence of extracellular Ca2+, after cells were treated with 1 microM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor), 10 microM histamine did not increase [Ca2+]i. After pretreatment with 10 microM histamine in a Ca2+-free medium for several minutes, addition of 3 mM Ca2+ induced [Ca2+]i increases. Histamine (10 microM)-induced intracellular Ca2+ release was abolished by inhibiting phospholipase C with 2 microM 1-(6-((17 beta-3- methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl)-1H-pyrrole-2,5-dione (U73122), and by 10 microM pyrilamine but was not altered by 50 microM cimetidine. Collectively, the present study shows that histamine induced [Ca2+]i transients in PC3 human prostate cancer cells by stimulating H1 histamine receptors leading to Ca2+ release from the endoplasmic reticulum in an inositol 1,4,5-trisphosphate-dependent manner, and by inducing Ca2+ entry.

Maximization of injection volumes for DNA analysis in capillary electrophoresis

We report concentration and separation of DNA in the presence of electroosmotic flow (EOF) using poly(ethylene oxide) (PEO) solution. DNA fragments migrating against EOF stacked between the sample zone and PEO solution. To maximize the injection volume, several factors, such as concentrations of Tris-borate (TB) buffer and PEO solution, capillary size, and matrix, were carefully evaluated. The use of 25 mM TB buffers, pH 10.0, containing suitable amounts (less than 10 mM) of salts, such as sodium chloride, sodium phosphate, and sodium acetate, to prepare DNA is essential for the concentration of large-volume samples. In the presence of salts, the peaks also became sharper and the fluorescence intensity of DNA complexes increased. Using 2.5% PEO and a 150 microm capillary filled with 400 mM TB buffer, pH 10.0, up to 5 microL DNA samples (phiX 174 RF DNA-HaeIII digest or the mixture of pBR 322/HaeIII, pBR 328/Bg/I, and pBR 328/HinfI digests) have been analyzed, resulting in more than 400-fold improvements in the sensitivity compared to that by conventional injections (ca. 36 nL). Moreover, this method allows the analysis of 3.5 microL PCR products amplified after 17 cycles without any sample pretreatment.

Tau protein expression in frontotemporal dementias

The syndrome of frontotemporal dementia represents a diverse group of diseases presenting with behavioral and cognitive disturbances. The expression of the microtubule-associated protein tau was studied in postmortem samples of frontal cortex of 19 cases (12 Pick's disease A, B, C; 4 dementia lacking distinct histology; 3 motor neuron disease type) by Western blotting with a phosphorylation-independent anti-tau antibody. The presence of tau protein was detected in all cases evaluated, including the 11 brains classified as frontotemporal lobe degeneration (diagnostic categories Pick's disease B, C and dementia lacking distinct histology). These findings indicate that the recently reported decreased expression of tau protein in frontotemporal lobe degeneration represents pathogenic mechanism of neurodegeneration detectable only in a special subset of these disorders.

Mechanism of bifonazole-induced [Ca2+]i increases in MDCK renal tubular cells

The effect of the antifungal drug bifonazole on Ca2+ homeostasis in Madin Darby canine kidney (MDCK) cells was investigated. Cell suspensions were loaded with the Ca2+-sensitive dye fura-2, and the fluorescence changes were measured with a spectrofluorophotometer. At concentrations between 10-80 microM bifonazole increased cytosolic free Ca2+ levels ([Ca2+]i) in a concentration-dependent manner. The Ca2+ signals were partly inhibited by removing extracellular Ca2+. Bifonazole (40 microM) released Ca2+ from the store sensitive to 1 microM thapsigargin, an endopolasmic reticulum Ca2+ pump inhibitor. Bifonazole (40 microM) per se induced capacitative Ca2+ entry while reduced 1 microM thapsigargin-induced capacitative Ca2+ entry. Inositol 1,4,5-trisphosphate may be involved in bifonazole-induced Ca2+ release because inhibiting phospholipase C with 2 microM U73122 partly reduced the bifonazole response. Together, bifonazole increased [Ca2+]i in renal tubular cells by inducing intracellular Ca2+ release and extracellular Ca2+ influx.

Fendiline mobilizes intracellular Ca2+ in Chang liver cells

1. The effects of the antianginal drug fendiline (N-[3,3-diphenylpropyl]-alpha-methyl-benzylamine) on intracellular free Ca2+ levels ([Ca2+](i)) in Chang liver cells were evaluated using fura-2 as a fluorescent Ca2+ indicator. 2. Fendiline (1-100 micromol/L) increased [Ca2+](i) in a concentration-dependent manner, with an EC50 of 25 micromol/L. 3. The [Ca2+](i) response was composed of an initial rise and a slow decay to a sustained phase. Removal of extracellular Ca2+ partly reduced the [Ca2+](i) signals. 4. Fendiline (10 micromol/L)-induced release of intracellular Ca2+ was reduced by 65% following pretreatment with 1 micromol/L thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor) to deplete Ca2+ stored in the endoplasmic reticulum. 5. After pretreatment with 10 micromol/L fendiline in Ca2+-free medium for several minutes, addition of 3 mmol/L Ca2+ induced an increase in [Ca2+](i) of a magnitude four-fold greater than control. This increase in [Ca2+](i) was not reduced by 10 micromol/L SKF96365, econazole, nifedipine or verapamil. 6. Fendiline (10 micromol/L)-induced release of intracellular Ca2+ was not altered by inhibition of phospholipase C with 2 micromol/L 1-(6-((17beta-3-methoxyestra-1,3,5(10)-trien-17-yl)amino) hexyl)-1H-pyrrole-2,5-dione (U73122). 7. The results of the present study show that fendiline induces an increase in [Ca2+](i) in Chang liver cells by releasing stored Ca2+ in an inositol 1,4,5-trisphosphate-independent manner and by causing extracellular Ca2+ influx.

Analysis of large-volume DNA markers and polymerase chain reaction products by capillary electrophoresis in the presence of electroosmotic flow

We have demonstrated on-line concentration and separation of DNA in the presence of electroosmotic flow (EOF) using poly(ethylene oxide) (PEO) solutions. After injecting large-volumes DNA samples, PEO solutions entered a capillary filled with 400 mM Tris-borate (TB) buffers by EOF and acted as sieving matrices. DNA fragments stacked between the sample zone and PEO solutions. Because sample matrixes affected PEO adsorption on the capillary wall, leading to changes in EOF, migration time, concentration, and resolving power varied with the injection length. When injecting phiX174 RF DNA-HaeIII digest prepared in 5 mM Tris-HCl buffer, pH 7.0, at 250 V/cm, peak height increased linearly as a function of injection volume up to 0.9 microl (injection time 150 s). The sensitivity improvement was 100-fold compare to that injected at 25 V/cm for 10 s (0.006 microl). When injecting 1.54 microl of GeneScan 1000 ROX, the sensitivity improvement was 265-fold. The sensitivity improvement was 40-fold when injecting 0.17 microl DNA sample containing pBR 322/HaeIII, pBR 328/BglI, and pBR 328/HinfI digests prepared in phosphate-buffered saline. This method allows the analysis of polymerase chain reaction (PCR) products amplified after 17 cycles when injecting 0.32 microl (at 30 cm height for 300 s). The total analysis time was shorter (91.6 min) than that (119.6 min) obtained from injecting PCR products after 32 cycles for 10 s.

Optimizing separation conditions for polycyclic aromatic hydrocarbons in micellar electrokinetic chromatography

We report the separation of polycyclic aromatic hydrocarbons (PAHs) using 0.1% poly(ethylene oxide) (PEO) in micellar electrokinetic chromatography (MEKC). In the presence of PEO, adsorption of PAHs on the capillary wall was reduced, leading to better resolution and reproducibility. Effects of tetrapentylammonium iodide (TPAI), dextran sulfate (DS), methanol, and sodium lauryl sulfate (SDS) on the separation of PAHs were elucidated. In terms of resolution and speed, DS, compared to TPAI, is a better additive for separation of PAHs. When using 0.1% PEO solution containing 45% methanol, 50 mM SDS, and 0.02% DS, separation of 10 PAHs containing 2 to 5 benzene rings was accomplished in less than 12 min at 15 kV in a commercial CE system. The method has also been tested for separating seven PAHs with high quantum yields when excited at 325 nm using a He-Cd laser. Unfortunately, separation of the seven PAHs was not achieved and sensitivity diminished under the same conditions. To optimize sensitivity, resolution and speed, a stepwise technique in MEKC has been proposed. The seven PAHs were resolved in 35 min at 15 kV when separation was performed in 0.1% PEO solution containing 35 mM SDS, 40% methanol and 0.02% DS for 2 min, and subsequently in 0.1% PEO solution containing 20 mM SDS, 50% methanol, and 0.02% DS.

Regulation of electroosmotic flow and electrophoretic mobility of proteins for concentration without desalting

Proteins were concentrated and separated in 0.6% poly(ethylene oxide) (PEO) solution using a capillary filled with Tris-borate (TB) buffer prior to analysis and detected by laser-induced native fluorescence using a pulsed Nd:YAG laser. During the concentration and separation, PEO solution entered the capillary by electroosmotic flow. When proteins dissolved in high salts (phosphate-buffered saline) were separated using 0.6% PEO solution prepared in 200 mM TB buffer, pH 9.0, the limits of detection (LODs) at signal-to noise ratios=3 for carbonic anhydrase (CA) and alpha-lactalbumin (alpha-lac) were on the levels of sub microM and microM, respectively. The LOD values compared to those obtained in 38 mM TB buffer were relatively high, which is likely due to salt quenching, Joule heating and poor stacking. To improve sensitivity for analysis of proteins in high-conductivity media, two on-line concentration approaches without desalting were developed. When using a capillary filled with 1.5 M TB buffer, pH 10.0, and PEO solution prepared in 800 mM TB buffer, pH 9.0, the LOD values for CA and alpha-lac were 13.8 nM and 126.0 nM, respectively, which were about 4.7 and 11.2-fold sensitivity enhancements compared to those obtained by a conventional hydrodynamic injection (30 cm height for 10 s), respectively. The sensitivity was further improved by injecting a short plug of low pH buffer after protein injection using a capillary filled with 1.5 M TB buffer, pH 10.0, and PEO solution prepared in 400 mM TB buffer, pH 9.0. A linear relationship between the peak height and the injection volume up to 0.81 microl was obtained and the LOD values for CA and alpha-lac were down to 4.7 and 37.8 nM.

A new strategy for optimizing sensitivity, speed, and resolution in capillary electrophoretic separation of DNA

DNA separations were performed in poly(ethylene oxide) (PEO) solutions prepared in 100 mM Tris-boric acid (TB) buffers using a capillary filled with TB buffers with concentrations up to 2.5 M, pH 10.0. The electroosmotic flow (EOF) increased with increasing the concentration of TB buffers till 1.5 M as a result of decreasing PEO adsorption on the capillary wall. At high TB concentrations (> 1.5 M), the peaks corresponding to small DNA fragments (11 and 8 base pairs) became sharper and were detected. Relative standard deviations of the EOF coefficient and the migration times of the DNA fragments were all less than 1% using a capillary filled with TB buffers at concentrations higher than 1.5 M. When separations were performed at different pH values of PEO solutions and TB buffers, better results in terms of sensitivity, speed, and resolution were generally achieved. The fluorescence intensity of the 2176 bp fragment obtained at pH values of TB buffers/PEO solutions 10.0/8.2 was 27-fold of that at pH values 8.2/8.2. The enhancement was related to effects of pH and borate on fluorescence intensity, DNA conformation, stacking, and interactions with the capillary wall. Using a capillary filled with 400 mM TB buffers, pH 10.0, the separation of DNA (pBR 322/HaeIII digest, pBR 328/Bg/I digest and pBR 328/HinfI digest) in 1.5% PEO solutions prepared in 100 mM TB buffers, pH 9.0, at 375 V/cm was accomplished in less than 18 min.

Mechanisms of diethylstilbestrol-induced calcium movement in MG63 human osteosarcoma cells

The effect of the estrogen diethylstilbestrol (DES) on cytosolic free Ca(2+) levels ([Ca(2+)](i)) in MG63 human osteoblasts was explored by using fura-2 as a Ca(2+) indicator. DES at concentrations between 5--20 microM induced an immediate increase in [Ca(2+)](i) in a concentration-dependent manner with an EC(50) of 10 microM. Removing extracellular Ca(2+) reduced the Ca(2+) signal by 70%. Pretreatment with 50 microM La(3+) or 10 microM of nifedipine, verapamil and diltiazem did not change 20 microM DES-induced [Ca(2+)](i) increases. Addition of 3 mM Ca(2+) increased [Ca(2+)](i) in cells pretreated with 20 microM DES in Ca(2+)-free medium. Pretreatment with 1 microM thapsigargin (an endoplasmic reticulum Ca(2+) pump inhibitor) to deplete the endoplasmic reticulum Ca(2+) store partly inhibited 20 microM DES-induced Ca(2+) release, but addition of carbonylcyanide m-chlorophenylhydrazone (CCCP; a mitochondrial uncoupler) and thapsigargin together abolished DES-induced Ca(2+) release. Conversely, pretreatment with 20 microM DES abrogated CCCP- and thapsigargin-induced Ca(2+) release. Inhibition of phospholipase C activity with 2 microM U73122 did not alter 20 microM DES-induced Ca2+ release. Another estrogen 17beta-estradiol also increased [Ca(2+)](i) in a concentration-dependent manner with an EC50 of 7 microM. Together, the data indicate that in human osteoblasts, DES increased [Ca(2+)](i) via causing Ca(2+) release from both mitochondria and the endoplasmic reticulum in a phospholipase C-independent manner, and by causing Ca(2+) influx.

Fendiline, an anti-anginal drug, increases intracellular Ca2+ in PC3 human prostate cancer cells

BACKGROUND

The effects of the anti-anginal drug fendiline on intracellular Ca2+ concentrations ([Ca2+]i) in human PC3 prostate cancer cells were examined.

METHODS

[Ca2+]i was measured using the fluorescent dye fura-2.

RESULTS

Fendiline (0.5-100 microM) increased [Ca2+]i in a concentration-dependent manner. Ca2+ removal partly inhibited the Ca2+ signals. In Ca2+-free medium, pretreatment with 100 microM fendiline inhibited most of the [Ca2+]i increase induced by 1 microM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor), and pretreatment with thapsigargin abolished the fendiline-induced [Ca2+]i increases. Adding 3 mM Ca2+ increased [Ca2+]i in cells pretreated with 0.5-200 microM fendiline in Ca2+-free medium. Pretreatment with 1 microM U73122 to block the formation of inositol-1.4.5-trisphosphate (IP3) did not alter fendiline-induced internal Ca2+ release.

CONCLUSIONS

The anti-anginal drug fendiline induced internal Ca2+ release and external Ca2+ entry. Because prolonged increases in [Ca2+]i may lead to cell injury and death, the long-term effect of fendiline on the function of prostate cancer cells should be investigated.

Separation of dsDNA in the presence of electroosmotic flow under discontinuous conditions

Separations of phiX-174/HaeIII DNA restriction fragments have been performed in the presence of electroosmotic flow (EOF) using five different polymer solutions, including linear polyacrylamide (LPA), poly(ethylene oxide) (PEO), hydroxypropylcellulose (HPC), hydroxyethylcellulose (HEC), and agarose. During the separation, polymer solutions entered the capillary by EOF. When using LPA solutions, bulk EOF is small due to adsorption on the capillary wall. On the other hand, separation is faster and better for the large DNA fragments (> 872 base pairs, bp) using derivative celluloses and PEO solutions. Several approaches to optimum resolution and speed by controlling EOF and/or altering electrophoretic mobility of DNA have been developed, including (i) stepwise changes of ethidium bromide (0.5-5 microg/mL), (ii) voltage programming (125-375 V/cm), (iii) use of mixed polymer solutions, and (iv) use of high concentrations of Tris-borate (TB) buffers. The DNA fragments ranging from 434 to 653 bp that were not separated using 2% PEO (8,000,000) under isocratic conditions have been completely resolved by either stepwise changes of ethidium bromide or voltage programming. Compared to PEO solutions, mixed polymer solutions prepared from PEO and HEC provide higher resolving power. Using a capillary filled with 600 mM TB buffers, pH 10.0, high-speed (< 15 min) separation of DNA (pBR 322/HaeIII digest, pBR 328/ Bg/l digest and pBR 328/Hinfl digest) has been achieved in 1.5% PEO.

Effects of the antianginal drug fendiline on Ca2+ movement in hepatoma cells

This study investigated the effect of the anti-anginal drug, fendiline, on intracellular free Ca2+ levels ([Ca2+]i) in HA/ 22 human hepatoma cells by using fura-2 as a fluorescent Ca2+ dye. Fendiline (1-100 microM) increased [Ca2+]i with an EC50 of 25 microM. Removal of extracellular Ca2+ reduced the [Ca2+]i signals by 51 +/- 5%. Fendiline (10 microM)-induced Ca2+ release was abolished by pretreatment with 1 microM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor). Inhibition of phospholipase C with 2 microM 1-(6-((17beta-3-methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl)-1H-pyrrole-2,5-dione (U73122) did not alter 10 microM fendiline-induced Ca2+ release. Several other calmodulin antagonists, such as phenoxybenzamine (100-200 microM), trifluoperazine (5-50 microM), and fluphenazine-N-chloroethane (2-100 microM), had no effect on [Ca2+]i. Together, it was found that fendiline increased [Ca2+]i in human hepatoma cells by discharging Ca2+ from the endoplasmic reticulum in an inositol 1,4,5-trisphosphate-independent manner and by inducing Ca2+ entry. This effect of fendiline does not appear to be via antagonism of calmodulin.

Clomiphene, an ovulation-inducing agent, causes [Ca2+]i increases in human osteoblast-like cells

The effect of clomiphene, an ovulation-inducing agent, on cytosolic free Ca2+ levels ([Ca2+]i) in MG63 human osteosarcoma cells was explored by using fura-2 as a Ca2+ indicator. Clomiphene at concentrations between 5-75 microM increased [Ca2+]i in a concentration-dependent manner with an EC50 of 50 microM. The [Ca2+]i signal consisted of an initial rise and a sustained phase. Ca2+ removal reduced the Ca2+ signal by 40+/-10%. The [Ca2+]i increase induced by 50 microM clomiphene was inhibited by 80+/-5% by 10 microM nifedipine, but was insensitive to 50 microM La3+ or 10 microM verapamil. In Ca2+-free medium, pretreatment with 50 microM brefeldin A (to disrupt the Golgi complex Ca2+ store), 1 microM thapsigargin (to inhibit the endoplasmic reticulum Ca2+ pump), and carbonylcyanide m-chlorophenylhydrazone (CCCP; to uncouple mitochondria) inhibited 51+/-3% of 50 microM clomiphene-induced Ca2+ release; conversely, pretreatment with 50 microM clomiphene abolished the [Ca2+]i increase induced by thapsigargin, CCCP, and brefeldin A. The Ca2+ release-induced by 50 pM clomiphene was unchanged by inhibition of phospholipase C with 2 microM 1-(6-((17beta-3-methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl)-1H-pyrrole-2,5-dione (U73122). Collectively, the results suggest that clomiphene increased [Ca2+]i, in osteoblast-like cells, by releasing intracellular Ca2+ in a phospholipase C-independent manner and by causing nifedipine-sensitive Ca2+ influx.

Tamoxifen-induced Ca2+ mobilization in bladder female transitional carcinoma cells

This study examined the effect of tamoxifen, an anti-breast cancer drug, on Ca2+ handling in bladder female transitional cancer cells. Changes in cytosolic free Ca2+ levels were recorded by using the Ca2+-sensitive dye fura-2. In a dose-dependent manner, tamoxifen induced intracellular free Ca2+ concentrations ([Ca2+]i) increases between 5 and 20 microM with an EC50 of 10 microM. External Ca2+ removal reduced the response by 60+/-6%. Addition of 3 mM Ca2+ caused a [Ca2+]i increase after pretreatment with 10 microM tamoxifen in Ca2+-free medium. In Ca2+-free medium, pretreatment with 10 microM tamoxifen abolished the [Ca2+]i increase induced by 1 microM thapsigargin, an endoplasmic reticulum Ca2+ pump inhibitor. Conversely, pretreatment with 1 microM thapsigargin prevented tamoxifen from releasing more Ca2+. Inhibition of phospholipase C-dependent inositol 1,4,5-tris-phosphate formation with 2 microM U73122 did not alter 10 microM tamoxifen-induced Ca2+ release. The [Ca2+]i increase induced by 5 microM tamoxifen was not altered by 10 microM La3+, nifedipine, verapamil, and diltiazem. Collectively, it was found that tamoxifen increased [Ca2+]i in bladder cancer cells by releasing Ca2+ from the endoplasmic reticulum Ca2+ stores in a manner independent of phospholipase C activity, and by inducing Ca2+ entry from external medium.

Effect of fluoxetine on intracellular Ca2+ levels in bladder female transitional carcinoma (BFTC) cells

The effect of the antidepressant fluoxetine on Ca2+ signaling in cultured cells was largely unknown. The effect of various concentrations of fluoxetine on [Ca 2+] i in populations of bladder female transitional cancer (BFTC) cells was evaluated by using fura-2 as a Ca2+ probe. Fluoxetine increased [Ca 2+] i concentration dependently (20-100 microM) with an EC50 value of 30 microM. The response was inhibited by 50-60% on extracellular Ca2+ removal. In Ca2+ -free medium, pretreatment with 1 microM thapsigargin (an inhibitor of the endoplasmic reticulum Ca2+ pump) abolished 50 microM fluoxetine-induced Ca2+ release; whereas pretreatment with fluoxetine did not alter the thapsigargin-induced Ca2+ response. Addition of 3 mM Ca2+ increased [Ca 2+] i after pretreatment with 50 microM fluoxetine in Ca2+ -free medium, suggestive of fluoxetine-induced capacitative Ca2+ entry. Suppression of inositol 1,4,5-trisphosphate formation by 2 microM U73122 (a phospholipase C inhibitor) did not affect 50 microM fluoxetine-induced Ca2+ release. Collectively, this study shows that fluoxetine increased [Ca 2+] i in bladder cancer cells in a concentration-dependent fashion, by releasing Ca2+ from thapsigargin-sensitive Ca2+ stores in an IP3-independent manner, and by inducing Ca2+ influx from extracellular medium.

Direct vertical electroelution of protein from a PhastSystem band for mass spectrometric identification at the level of a few picomoles

An electroelution apparatus prototype of a new design was constructed. In that design, the electric field passes vertically through the protein band located on a horizontal (PhastSystem) minigel polymerized on a net of Gel-Fix (Serva). A simple, home-made apparatus allows for electroelution of protein bands at the level of a few picomoles and their identification, after concentration, by matrix-assisted laser desorption/ionization-time of flight mass spectrometry. The technique is applicable to one-dimensional (1-D) or two-dimensional (2-D) gels of any size, but has been exemplified only by application to 1-D minigels to demonstrate the lower limits of protein load of the method. When in the course of further development of the prototype it will be combined with a modification to two dimensions of the electroelution mechanism under computer control of the high-performance gel electrophoresis apparatus (formerly of LabIntelligence), the new design appears uniquely qualified for an automated spot elution from 2-D gels under avoidance of gel sectioning.

Fendiline-Induced Ca2+ movement in A10 smooth muscle cells

The effect of fendiline, an anti-anginal drug, on cytosolic free Ca2+ levels ([Ca2+]i) in A10 smooth muscle cells was explored by using fura-2 as a Ca2+ indicator. Fendiline at concentrations between 10-50 microM increased [Ca2+]i in a concentration-dependent manner with an EC50 of 20 microM. External Ca2+ removal reduced the Ca2+ signal by 75%. Addition of 3 mM Ca2+ increased [Ca2+]i in cells pretreated with fendiline in Ca2+-free medium. The 50 microM fendiline-induced [Ca2+]i increase in Ca2+-containing medium was inhibited by 10 microM of La3+, nifedipine, or verapamil. In Ca2+-free medium, pretreatment with 1 microM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor) to deplete the endoplasmic reticulum Ca2+ store partly inhibited 50 microM fendiline-induced Ca2+ release; whereas pretreatment with 50 microM fendiline abolished 1 microM thapsigargin-induced Ca2+ release. Inhibition of phospholipase C activity with 2 microM U73122 did not alter 50 microM fendiline-induced Ca2+ release. Incubation with 50 microM fendiline for 10-30 min decreased cell viability by 10-20%. Together, the findings indicate that in smooth muscle cells fendiline induced [Ca2+]i increases. Fendiline acted by activating Ca2+ influx via L-type Ca2+ channels, and by releasing internal Ca2+ in a phospholipase C-independent manner. Prolonged exposure of cells to fendiline induced cell death.

Electroelution of proteins from bands in gel electrophoresis without gel sectioning for the purpose of protein transfer into mass spectrometry: elements of a new procedure

Electroelution of protein bands from a gel has advantages over the competitive common technique requiring gel sectioning with respect to yield, speed and the potential for computer-controlled application to multicomponent two-dimensional (2-D) gels. The electroelution design for the commercial high-performance gel electrophoresis (HPGE) apparatus represented the most advanced technique to date until the recent discontinuation of its production. The present report serves to summarize the necessary design elements for the purpose of renewing and further developing the electroelution technique. A rudimentary technique is presented by which the electroeluate is collected in a glass tube superimposed on a reversibly stained gel band and connected to an anolyte reservoir. Although the stain used is insufficiently sensitive, the technique allowed for the qualitative verification of its usefulness in the transfer of the electroeluate into mass spectrometry.

Characterization of histamine-induced increases in intracellular free Ca2+ concentrations in Chang liver cells

The effect of histamine on intracellular free Ca2+ levels ([Ca2+]i) in Chang liver cells were investigated by using fura-2 as a Ca2+ dye. Histamine (0.2-50 microM) increased [Ca2+]i in a concentration-dependent manner with an EC50 value of 0.8 microM. The [Ca2+]i response comprised an initial rise, a slow decay, and a sustained phase. Extracellular Ca2+ removal inhibited 50% of the maximum [Ca2+]i signal and abolished the sustained phase. After pretreatment with 5 microM histamine in Ca2+-free medium for 4 min, addition of 3 mM Ca2+ induced a [Ca2+]i increase with a magnitude 7-fold greater than control. In Ca2+-free medium, after treatment with 1 microM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor), 5 microM histamine failed to increase [Ca2+]i. Histamine (5 microM)-induced intracellular Ca2+ release was abolished

Dynamic modification of the capillary wall for electrophoretic separations of small ions

Separations of small ions were carried out under nonequilibrated conditions using capillaries treated with NaOH, HCl, or tris(hydroxymethyl)aminomethane (Tris) prior to analysis. For separations of benzoic acid isomers or acids and amines under weakly acidic conditions, capillaries flushed with 0.1 M NaOH and subsequently with running buffers prior to analysis were used. Separations of six benzoic acid isomers were accomplished in 4 min in 1 mM phosphate buffers, pH 4.01, containing 2.5 mM hydroxypropyl-beta-cyclodextrin. Without additives, the separation of biological amines and acids were also achieved in 10 min at pH 4.01. Capillaries treated with 0.1 M HCl prior to analysis were tested in separations of six phenols in 5 mM Tris solutions at pH 7.0. As a result of small electrophoretic mobilities of phenols against a small electroosmotic flow, resolution was optimized. We also found that reproducibility was improved using capillaries treated with HCl. The relative standard deviations of migration mobility of phenols were less than 1%, which were smaller than those obtained using capillaries treated with 0.1 M NaOH or Tris.

On-line concentration and separation of proteins by capillary electrophoresis using polymer solutions

Proteins were separated in 0.6% poly(ethylene oxide) (PEO) solutions using a capillary filled with buffers prior to analysis and were detected by laser-induced native fluorescence using a pulsed Nd:YAG laser. PEO solutions entered the capillary by electroosmotic flow (EOF) during the separation. The composition and concentration of the buffer affected the adsorption of PEO molecules on the capillary surface and, consequently caused changes in the EOF. Short separation times (< 7 min) were achieved on a sample solution of five proteins in a 0.6% PEO solution containing 5 microg/mL ethidium bromide using a capillary pre-filled with 100 mM TRIS-borate (TB) buffers (pH 10,0). We also extended this method for on-line concentration and separation of proteins. Proteins dissolved in low-conductivity media stacked in both TB buffers and in PEO solutions. The peak height was proportional to the injection volume up to 2.1 microL using an 80-cm capillary filled with 400 mM TB buffers. Using large injection volumes (2.1 microL), we achieved a limit of detection (S/N = 3) of 31 pM for carbonic anhydrase, which was a 1696-fold sensitivity enhancement compared to a conventional injection method (1 kV for 10 s). In high-conductivity media (urine matrix), stacking occurred at the boundary between the sample zone and PEO solutions. A urine sample without any pretreatment was analyzed, and after stacking, several peaks were detected. Spiking the urine sample with human serum albumin (HSA) affected the fluorescent intensity of some analytes as a result of interaction with HSA.

Effect of ionic strength, pH and polymer concentration on the separation of DNA fragments in the presence of electroosmotic flow

DNA separations in the presence of electroosmotic flow (EOF) using poly(ethylene oxide) (PEO) solutions have been demonstrated. During the separations, PEO entered capillaries filled with Tris-borate (TB) free buffers by EOF and acted as sieving matrices. We have found that ionic strength and pH of polymer and free solutions affect the bulk EOF and resolution differently from that in capillary zone electrophoresis. The EOF coefficient increases with increasing ionic strength of the free TB buffers as a result of decreases in the adsorption of PEO molecules. In contrast, the bulk EOF decreases with increasing the ionic strength of polymer solutions using capillaries filled with high concentrations of free TB buffers. Although resolution values are high due to larger differential migration times between any two DNA fragments in a small bulk EOF using 10 mM TB buffers, use of a capillary filled with at least 100 mM TB free buffers is suggested for high-speed separations. On the side of PEO solutions, 1.5% PEO solutions prepared in 100 to 200 mM TB buffers are more proper in terms of resolution and speed. The separation of DNA markers V and VI was accomplished less than 29 min in 1.5% PEO solutions prepared in 100 mM TB buffers, pH 7.0 at 500 V/cm using a capillary filled with 10 mM free TB buffers, pH 7.0.

On-column preconcentration and separation of DNA fragments using polymer solutions in the presence of electroosmotic flow

We demonstrated DNA preconcentration and separation in the presence of electroosmotic flow (EOF) using poly(ethylene oxide) (PEO) solutions. After injecting large volumes of DNA samples into a capillary filled with free tris(hydroxymethyl)aminomethane (Tris)-borate (TB) buffers, PEO solutions entered the capillary by EOF and acted as sieving matrices. In contrast to conventional methods (in the absence of EOF), controlling the EOF was also useful for resolution optimization. We have found that PEO adsorption on the capillary wall was more pronounced when low ionic strength buffers were used. Thus, the EOF decreased with increasing injection length, which led to longer migration times and changes in resolution and stacking efficiency. All resolution values were higher than 1.5 when 1.0 microg/mL DNA samples were injected at 240 V/cm for 60 s (0.67 microL). In addition, as low as 0.015 microg/mL DNA samples (an about 66-fold increase in sensitivity) were detected when the injection was performed at 250 V/cm for 60 s.

Lipid-rich diffuse malignant mesothelioma: a case report

An 80-year old man presented with shortness of breath and was found to have a large right pleural effusion. Cytology of the pleural fluid showed atypical papillary clusters of epithelioid cells. Multiple white-yellow nodules studding the pleural surfaces were seen at thoracoscopy, and biopsies showed solid and papillary clusters of large epithelioid cells with abundant cytoplasm filled with clear vacuoles. Special stains and electron microscopic findings indicated that the tumor was a diffuse malignant mesothelioma with numerous intracytoplasmic lipid vacuoles. Fat stain may be useful at time of frozen section for a pleural-based tumor with vacuolated cells, and the presence of lipid vacuoles in a pleural-based tumor does not exclude diffuse malignant mesothelioma.

Risk factors of mortality in perforated peptic ulcer

OBJECTIVE

To assess the risk factors that influence mortality from perforated peptic ulcer.

DESIGN

Retrospective study.

SETTING

General hospital, Taiwan.

SUBJECTS

179 patients who had their perforated peptic ulcers operated on and who had minimum follow-up of one year.

MAIN OUTCOME MEASURES

Mortality.

RESULTS

The overall mortality was 15% (26/179). Of the 26 patients who died, the cause of death was uncontrolled systemic infection in 21 (81%), hypovolaemic shock in 2, and fatal arrhythmia and heart failure in 1 each. 15 of the patients who died of sepsis did not have fulminant abdominal sepsis. Most deaths occurred early after operation, (range 1-96 days). Old age, preoperative shock, and type of operation seemed to be related to these deaths on univariate analysis, but multivariate analysis showed that coexisting medical illness, delayed treatment, and low albumin concentration were independent risk factors for mortality.

CONCLUSIONS

To improve the result of treatment of perforated peptic ulcer, the diagnosis and treatment should not be delayed, the associated medical illnesses should be treated, and nutritional support should be given.

Iteration-free fractal image coding based on efficient domain pool design

The domain pool design is one of the dominant issues which affect the coding performance of fractal image compression. In this paper, we employ the LBG algorithm and propose a block averaging method to design the efficient domain pools based on a proposed iteration-free fractal image codec. The redundancies between the generated domain blocks are reduced by the proposed methods. Therefore, we can obtain the domain pools that are more efficient than those in the conventional fractal coding schemes and thus the coding performance is improved. On the other hand, the iteration process in the conventional fractal coding scheme not only requires a large size of memory and a high computation complexity but also prolongs the decoding process. The proposed iteration-free fractal codec can overcome the problems above. In computer simulation, both the LBG-based and block-averaging methods for the domain pool design in the proposed iteration free scheme achieve excellent performances. For example, based on the proposed block-averaging method, the decoded Lena image has at least a 0.5 dB higher PSNR (under the same bit rate) and an eight-time faster decoding speed than the conventional fractal coding schemes that require iterations.

Analysis of prognostic factors in Chinese women with breast cancer in southern Taiwan

BACKGROUND

We conducted a retrospective review of all early-stage breast cancer patients treated at the Veterans General Hospital-Kaohsiung to determine overall and disease-free survival rates, and to evaluate prognostic factors for these outcomes.

METHODS

During the period of October, 1990, to December, 1997, 332 patients with early-stage breast cancer were treated at our institution. Cox's multivariate regression analysis was used to select prognostic factors significant for overall survival and disease-free survival.

RESULTS

The survival rate for breast cancer patients was 88.35% at five years. Prognostic factors predicting breast cancer mortality included poorly differentiated histologic grade, four or more lymph nodes positive for metastasis and negative progesterone-receptor status. For disease recurrence, prognostic factors included positive nodes, aneuploidy and poorly differentiated histologic grading.

CONCLUSIONS

We conclude that a combination of lymph node status, DNA ploidy, histologic grading and progesterone-receptor status help to evaluate the possible outcomes for patients with breast cancer and to plan for optimal therapy.