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Background: While current guidelines recommend amiodarone and dronedarone for rhythm control in patients with atrial fibrillation (AF) and coronary artery disease (CAD), there was no comparative study of antiarrhythmic drugs (AADs) on the cardiovascular outcomes in general practice., Methods: This study included patients with AF and CAD who received their first prescription of amiodarone, class Ic AADs (flecainide, propafenone), dronedarone or sotalol between January 2016 and December 2020. The primary outcome was a composite of hospitalization for heart failure (HHF), stroke, acute myocardial infarction (AMI), and cardiovascular death. We used Cox proportional regression models, including with inverse probability of treatment weighting (IPTW), to estimate the relationship between AADs and cardiovascular outcomes., Results: Among the AF cohort consisting of 8752 patients, 1996 individuals had CAD, including 477 who took dronedarone and 1519 who took other AADs. After a median follow-up of 38 months, 46.3% of patients who took dronedarone and 54.4% of patients who took other AADs experienced cardiovascular events. Compared to dronedarone, the use of other AADs was associated with increased cardiovascular events after adjusting for covariates (hazard ratio [HR] 1.531, 95% confidence interval [CI] 1.112-2.141, p = 0.023) and IPTW (HR 1.491, 95% CI 1.174-1.992, p = 0.012). The secondary analysis showed that amiodarone and class Ic drugs were associated with an increased risk of HHF. The low number of subjects in the sotalol group limits data interpretation., Conclusion: For patients with AF and CAD, dronedarone was associated with better cardiovascular outcomes than other AADs. Amiodarone and class Ic AADs were associated with a higher risk of cardiovascular events, particularly HHF., Competing Interests: Declaration of competing interest The corresponding author has full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis. Conflict of interests is none., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Prostate cancer (PCa) is the most common non-skin cancer among men in the United States. However, the widely used protein biomarker in PCa, prostate-specific antigen (PSA), while useful for initial detection, its use alone cannot detect aggressive PCa and can lead to overtreatment. This chapter provides an overview of PCa protein biomarker development. It reviews the state-of-the-art liquid chromatography-mass spectrometry-based proteomics technologies for PCa biomarker development, such as enhancing the detection sensitivity of low-abundance proteins through antibody-based or antibody-independent protein/peptide enrichment, enriching post-translational modifications such as glycosylation as well as information-rich extracellular vesicles, and increasing accuracy and throughput using advanced data acquisition methodologies. This chapter also summarizes recent PCa biomarker validation studies that applied those techniques in diverse specimen types, including cell lines, tissues, proximal fluids, urine, and blood, developing novel protein biomarkers for various clinical applications, including early detection and diagnosis, prognosis, and therapeutic intervention of PCa., (Copyright © 2024. Published by Elsevier Inc.)

On-site nucleic acid testing (NAT) plays an important role for disease monitoring and pathogen diagnosis. In this work, we developed an automated and fully-integrated nucleic acid analyzer by combining the automated liquid handling robot technique with the microfluidic droplet-based real-time PCR assay technique. The present analyzer could achieve multiple operations including sample introduction, nucleic acid extraction based on magnetic solid-phase extraction, reverse transcription and, sample droplet generation, PCR amplification, real-time and dual fluorescence detection of droplet array. A strategy of constructing an integrated compact and low-cost system was adopted to minimize the analyzer size to 50 × 45 × 45 cm (length × width × height), and reduce the instrument cost to ca. $900 with a single analysis cost less than $5. A simple chip was also designed to pre-load reagents and carry oil-covered PCR reaction droplets. We applied the analyzer to identify eight types of influenza pathogens in human throat swabs, and the results were consistent with the colloidal gold method., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Objective: This study was to explore the risk factors for postoperative bladder neck contracture (BNC) after transurethral operation of prostate in patients with small-volume prostatic obstruction., Methods: Clinicopathologic data at our center from February 2016 to January 2020 were retrospectively collected and analyzed. Clinicopathological characteristics between patients with and without BNC were compared. Multivariate logistic regression was used to determine the risk factors for postoperative BNC., Results: There were a total of 39 patients (8.53%) with postoperative BNC. Multivariate logistic regression analysis demonstrated that preoperative bladder neck diameter (BND), intravesical prostatic protrusion (IPP), surgical methods (transurethral resection of prostate (TURP)/anatomical endoscopic enucleation of the prostate (AEEP)), and postoperative urinary tract infection (UTI) were independent risk factors for postoperative BNC in patients with small-volume prostatic obstruction (P < 0.05). The incidence of postoperative BNC in patients undergoing AEEP was significantly decreased compared with those undergoing TURP. The optimal cut-off value of preoperative IPP was 6.10 mm while the optimal cut-off value of preoperative BND was 2.52 cm., Conclusions: Larger preoperative bladder neck and higher preoperative IPP lead to decreased incidence of postoperative BNC in patients with small-volume prostatic obstruction. Active management of postoperative UTI could effectively prevent the occurrence of postoperative BNC. Compared with TURP, complete AEEP would contribute to reduce BNC in patients with small-volume prostatic obstruction., Competing Interests: Declaration of competing interest Not applicable., (Copyright © 2022 Asian Surgical Association and Taiwan Robotic Surgery Association. Published by Elsevier B.V. All rights reserved.)

Increasing evidence suggests that the presence and spatial localization and distribution pattern of tumor infiltrating lymphocytes (TILs) is associate with response to immunotherapies. Recent studies have identified TGF β activity and signaling as a determinant of T cell exclusion in the tumor microenvironment and poor response to PD-1/PD-L1 blockade. Here we coupled the artificial intelligence (AI)-powered digital image analysis and gene expression profiling as an integrative approach to quantify distribution of TILs and characterize the associated TGF β pathway activity. Analysis of T cell spatial distribution in the solid tumor biopsies revealed substantial differences in the distribution patterns. The digital image analysis approach achieves 74% concordance with the pathologist assessment for tumor-immune phenotypes. The transcriptomic profiling suggests that the TIL score was negatively correlated with TGF β pathway activation, together with elevated TGF β signaling activity observed in excluded and desert tumor phenotypes. The present results demonstrate that the automated digital pathology algorithm for quantitative analysis of CD8 immunohistochemistry image can successfully assign the tumor into one of three infiltration phenotypes: immune desert, immune excluded or immune inflamed. The association between "cold" tumor-immune phenotypes and TGF β signature further demonstrates their potential as predictive biomarkers to identify appropriate patients that may benefit from TGF β blockade., (© 2022 Chinese Pharmaceutical Association and Institute of Materia Medica, Chinese Academy of Medical Sciences. Production and hosting by Elsevier B.V.)

Background: The predictive values of the platelet to lymphocyte ratio (PLR) and red cell distribution width (RDW) have been demonstrated in different types of abdominal surgery. The aim of this study was to investigate the interest of the preoperative PLR and RDW as predictors of 30-day postoperative complications in patients with acute mesenteric ischemia (AMI)., Methods: Clinical data of 105 AMI patients were retrospectively reviewed. Postoperative complications were evaluated by the Clavien-Dindo classification. The cutoff values for neutrophil to lymphocyte ratio (NLR), PLR, and RDW were determined by receiver operating characteristic curves. Univariate and multivariate analyses evaluating the risk factors for postoperative complications were performed., Results: In the univariate analyses, advanced age, female, anemia, high white blood cell (WBC), high PLR, high NLR, high RDW, Charlson comorbidity index (CCI) score ≥2, and bowel resection were associated with the postoperative complications. A multivariable analysis revealed that advanced age, high PLR, high RDW, and bowel resection were independent predictors of postoperative complications., Conclusions: The PLR and RDW might play important roles in evaluation of the risk of postoperative complications in AMI patients. The preoperative PLR and RDW are simple and useful predictors of postoperative complications in AMI patients., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Cadmium, a toxic heavy metal, seriously affects human health and ecological security. The cation/H + exchanger (CAX) family is a unique metal transporter that plays a crucial role in Cd acquisition, transfer, and remission in plants. Although there are many studies related to the genome-wide analysis of Populus trichocarpa, little research has been done on the CAX family genes, especially concerning Cd stress. In this study, genome-wide analysis of the Populus CAX family identified seven stress-related CAX genes. The evolutionary tree indicated that the CaCA family genes were grouped into four clusters. Moreover, seven pairs of genes were derived by segmental duplication in poplars. Cis-acting element analysis identified numerous stress-related elements in the promoters of diverse PtrCAXs. Furthermore, some PtrCAXs were up-regulated by drought, beetle, and mechanical damage, indicating their possible function in regulating stress response. Under cadmium stress, all CAX genes in the roots were up-regulated. Our findings suggest that plants may regulate their response to Cd stress through the TF-CAXs module. Comprehensively investigating the CAX family provides a scientific basis for the phytoremediation of heavy metal pollution by Populus., (Copyright © 2022. Published by Elsevier B.V.)

Objective: Paclitaxel-coated balloons are used to reduce neointimal hyperplasia in native arteriovenous (AV) fistulas. However, no study specifically evaluated their effect on venous anastomotic stenosis of dialysis grafts. We aimed to compare the efficacy of angioplasty with drug-coated balloons (DCBs) and angioplasty with conventional balloons (CBs) for venous anastomotic stenosis in dysfunctional AV grafts., Methods: In this investigator-initiated, single-center, single-blinded, prospective randomized controlled trial, we randomly assigned 44 patients who had venous anastomotic stenosis to undergo angioplasty with DCBs (n = 22) or CBs (n = 22) from July 2015 to August 2018. Access function was observed per the hemodialysis center's protocols; ancillary angiographic follow-up was performed every 2 months for 1 year after the interventions. The primary end point was target lesion primary patency at 6 months. Secondary outcomes included anatomic and clinical success after angioplasty, circuit primary patency at 6 months and 1 year, and target lesion primary patency at 1 year., Results: At 6 months, target lesion primary patency in the DCB group was significantly greater than that in the CB group (41% vs 9%; hazard ratio [HR], 0.393; 95% confidence interval [CI], 0.194-0.795; P = .006), as was the primary patency of the entire access circuit (36% vs 9%; HR, 0.436; 95% CI, 0.218-0.870; P = .013). At 1 year, the target lesion primary patency in the DCB group remained greater than that in the CB group (23% vs 9%; HR, 0.477; 95% CI, 0.243-0.933; P = .019) but not the primary patency of the access circuit (14% vs 9%; HR, 0.552; 95% CI, 0.288-1.059; P = .056). No difference in anatomic or clinical success was observed; no major complications were noted., Conclusions: Angioplasty with DCBs showed a modest improvement in primary patency of venous anastomotic stenosis and all dialysis AV grafts at 6 months. The short-term benefit was not durable to 1 year, and reinterventions were eventually needed., (Copyright © 2019 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

As activity space measures are increasingly used to estimate exposure to environmental determinants of health, little is known about the stability of these measures over time. To test the stability of GPS-derived measures of activity-space footprint, size, and environmental features over time, we compared 14-day measures at baseline and six months later for 35 adults in a large city. Activity-space measures were based on convex hulls and 500 m route buffers, and included the geographic footprint (i.e. location of the activity space), size (i.e., area in square miles; (Cummins, 2007)), and environmental features including supermarket, fast-food restaurant, and parkland density. The proportion of the participants' smaller geographic footprint covered by the larger was, on average, 0.64 (SD 0.17) for the 500 m route buffer and 0.84 (SD 0.18) for the convex hull. Mean percent change in activity space size ranged from 36.3% (mean daily 500 m route buffer) to 221.3% (cumulative convex hull). Mean percent change in the density of environmental features ranged from 28.8 to 66.5%. Forty-one percent to 92.4% of the variance at one timepoint was predicted by environmental features measured within approximately six months. Activity-space size and environmental features were moderately to highly stable over six months, although there was considerable variation in stability between measures. Strategies for addressing measurement error in studies of activity space-health associations are discussed., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Objective: This study retrospectively evaluated the incidences of small supernumerary marker chromosomes (sSMCs) in prenatal diagnoses and detected with gain of pathogenic copy number variation through array comparative genomic hybridization (CGH) in a laboratory in Taiwan., Materials and Methods: We retrospectively searched and reviewed the sSMC cases detected during prenatal diagnoses in the Youthgene medical laboratory, between 2004 and 2015 and used array CGH to successfully analyze 45 of 47,XN,+mar or 47,XN + mar/46,XN., Results: A total of 68,087 cases of amniocentesis were analyzed, of which 59 were identified as sSMCs. The overall frequency of sSMCs was 0.087%, and 7 of 45 sSMCs were identified with gain of pathogenic copy number variation (CNV)., Conclusion: Array CGH offers useful tools that can be used to detect small fragments of chromosomal abnormalities and sSMC origins in prenatal diagnosis. In this study, we successfully used array CGH to detect 7 out of 45 sSMCs, which were identified with gain in pathogenic CNV., (Copyright © 2018. Published by Elsevier B.V.)

Background: The aim of this study is to investigate whether statin therapy can reduce new-onset acute coronary syndrome (ACS) in patients with rheumatoid arthritis (RA)., Methods: We used a database from the Registry for Catastrophic Illness from the National Health Research Institute (NHRI) in Taiwan. All RA patients aged 18 or older, diagnosed between 1995 and 2013, without previous cardiovascular events were included. We divided participants into quartiles according to the accumulated statin equivalent dosage and tertiles of period of days of statin treatment to examine the possible dose-response effect. To avoid confounding effects, a 1:4 propensity score matching and Cox's proportional hazard regression models were applied to estimate the hazard ratios for ACS events in patients with and without statin use., Results: Total 49,227 patients were included and PS matching identified 5483 patients receiving statins and 21,932 who did not. RA patients treated with statins had lower incidence of first ACS event (IRR 0.779, 95% CI: 0.654-0.927, p=0.005) after PS matching. Statin therapy is associated with reduced risk of new ACS before PS matching (HR=0.847, 95% CI: 0.737-0.973, p=0.019) and the beneficial effect is correlated with accumulated dose and therapy duration (HRs from Q1 to Q4 are 1.215, 0.825, 0.716 and 0.611, p<0.001 for trend; HRs from T1 to T3 are 1.100, 0.841 and 0.611, p<0.001 for trend). These results remained robust after propensity matching. Comparison between 6 different statins, rosuvastatin seems to be associated with better outcome on ACS primary prevention after excluding participants taking more than one kind of statin., Conclusions: Our study demonstrated that statin therapy is associated with lower event rate of new-onset ACS in RA patients and the beneficial effect is dose-responsive., (Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.)

Background: Left ventricular diastolic dysfunction (LVDD) is common among patients undergoing peritoneal dialysis (PD). Increased levels of inflammatory biomarkers, such as high-sensitivity C-reactive protein, predict the development of LVDD., Objectives: We hypothesized that PD patients with elevated high-sensitivity C-reactive protein levels might benefit from statin treatment for LVDD and designed a randomized clinical trial to prove the hypothesis., Methods: We screened 213 PD patients and randomly assigned 32 men and women with low-density lipoprotein cholesterol levels <130 mg/dL, high-sensitivity C-reactive protein levels of ≥1.5 mg/L, and LVDD, diagnosed by conventional and tissue Doppler imaging (TDI) echocardiography, to treatment with atorvastatin, 40 mg daily, or without. The primary end points were changes in TDI diastolic parameters or global strain imaging diastolic parameters., Results: Atorvastatin reduced low-density lipoprotein cholesterol levels by 43% and high-sensitivity C-reactive protein levels by 45% (both P < .001). Follow-up TDI showed significant improvement of early mitral flow velocities divided by early diastolic peak velocities of the mitral annulus at the medial and lateral site (Nominal change for E/E medial : -5.01 ± 6.36 vs 1.80 ± 6.59 for atorvastatin and control, respectively, P = .02). There was also a significant improvement in global strain imaging after atorvastatin treatment (global strain rate, -17.12 ± 1.42 vs -14.61 ± 1.78 for atorvastatin and control, respectively, P = .002 and E/SR IVR , 462.35 ± 110.54 vs 634.09 ± 116.81, P = .003)., Conclusions: In this trial of PD patients without hyperlipidemia but with elevated high-sensitivity C-reactive protein levels and LVDD, atorvastatin significantly improved cardiac diastolic function (ClinicalTrials.gov number, NCT01503671)., (Copyright © 2017. Published by Elsevier Inc.)

This work develops a composite system of reduced graphene oxide (rGO)-iron oxide nanoparticles (rGO-IONP) that can synergistically induce physical and chemical damage to methicillin-resistant Staphylococcus aureus (MRSA) that are present in subcutaneous abscesses. rGO-IONP was synthesized by the chemical deposition of Fe(2+)/Fe(3+) ions on nanosheets of rGO in aqueous ammonia. The antibacterial efficacy of the as-prepared rGO-IONP was evaluated in a mouse model with MRSA-infected subcutaneous abscesses. Upon exposure to a near-infrared laser in vitro, rGO-IONP synergistically generated localized heat and large amounts of hydroxyl radicals, which inactivated MRSA. The in vivo results reveal that combined treatment with localized heat and oxidative stress that is caused by hydroxyl radicals accelerated the healing of wounds associated with MRSA-infected abscesses. The above results demonstrate that an rGO-IONP nanocomposite system that can effectively inactivate multiple-drug-resistant bacteria in subcutaneous infections was successfully developed., From the Clinical Editor: The emergence of methicillin-resistant S. aureus (MRSA) has posed a significant problem in the clinical setting. Thus, it is imperative to develop new treatment strategies against this. In this study, the authors described the use of reduced graphene oxide (rGO)-iron oxide nanoparticles (rGO-IONP) to induce heat and chemical damage to MRSA. This approach may provide a platform the design of other treatment modalities against multiple-drug-resistant bacteria., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Current evidence suggests that angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) reduce the incidence of new atrial fibrillation (AF) in a variety of clinical conditions, including the treatment of left ventricular dysfunction or hypertension. Here we assessed whether ACEIs and ARBs could decrease incidence of new-onset AF in patients with end-stage renal disease (ESRD). We identified patients from the Registry for Catastrophic Illness, a nation-wide database encompassing almost all of the patients receiving dialysis therapy in Taiwan from 1995 to 2008. Propensity score matching and Cox proportional hazards regression models were used to estimate hazard ratios for new-onset AF. Among 113,186 patients, 13% received ACEIs, 14% received ARBs therapy, and 9% received ACEIs or ARBs alternatively. After a median follow-up of 1524 days, the incidence of new-onset AF significantly decreased in patients treated with ACEIs (hazard ratio 0.587, 95% confidence interval 0.519-0.663), ARBs (0.542, 0.461-0.637), or ACEIs/ARBs (0.793, 0.657-0.958). The prevention of new-onset AF was significantly better in patients taking longer duration of ACEI or ARB therapy. The effect remained robust in subgroup analyses. Thus both ACEIs and ARBs appear to be effective in the primary prevention of AF in patients with ESRD. Hence, renin-angiotensin system inhibition may be an emerging treatment target for the primary prevention of AF.

Mitochondrial transfer has been demonstrated to a play a physiological role in the rescuing of mitochondrial DNA deficient cells by co-culture with human mesenchymal stem cells. The successful replacement of mitochondria using microinjection into the embryo has been revealed to improve embryo maturation. Evidence of mitochondrial transfer has been shown to minimize injury of the ischemic-reperfusion rabbit heart model. In this mini review, the therapeutic strategies of mitochondrial diseases based on the concept of mitochondrial transfer are illustrated, as well as a novel approach to peptide-mediated mitochondrial delivery. The possible mechanism of peptide-mediated mitochondrial delivery in the treatment of the myoclonic epilepsy and ragged-red fiber disease is summarized. Understanding the feasibility of mitochondrial manipulation in cells facilitates novel therapeutic skills in the future clinical practice of mitochondrial disorder., (Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.)

The intracellular ice formation (IIF) behavior of Haliotis diversicolor (small abalone) eggs is investigated in this study, in relation to controlling the cooling rate and the concentration of dimethyl sulfoxide (DMSO). The IIF phenomena are monitored under a self-developed thermoelectric cooling (TEC) cryomicroscope system which can achieve accurate temperature control without the use of liquid nitrogen. The accuracy of the isothermal and ramp control is within ±0.5 °C. The IIF results indicate that the IIF of small abalone eggs is well suppressed at cooling rates of 1.5, 3, 7 and 12 °C/min with 2.0, 2.5, 3.0 and 4.0M DMSO in sea water. As 2.0M DMSO in sea water is the minimum concentration that has sufficient IIF suppression, it is selected as the suspension solution for the cryopreservation of small abalone eggs in order to consider the solution's toxicity effect. Moreover, IIF characteristics of the cumulative probability of IIF temperature distribution are shown to be well fitted by the Weibull probabilistic distribution. According to our IIF results and the Weibull distribution parameters, we conclude that cooling at 1.5 °C/min from 20 to -50 °C with 2.0M DMSO in sea water is more feasible than other combinations of cooling rates and DMSO concentrations in our experiments. Applying this protocol and observing the subsequent osmotic activity, 48.8% of small abalone eggs are osmotically active after thawing. In addition, the higher the cooling rate, the less chance of osmotically active eggs. A separate fertility test experiment, with a cryopreservation protocol of 1.5 °C/min cooling rate and 2.0M DMSO in sea water, achieves a hatching rate of 23.7%. This study is the first to characterize the IIF behavior of small abalone eggs in regard to the cooling rate and the DMSO concentration. The Weibull probabilistic model fitting in this study is an approach that can be applied by other researchers for effective cryopreservation variability estimation and analysis., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Two pentanuclear copper(I) thiolato clusters of the formula [Cu(5)(L)(3)](-) (L = pyridine-2,6-dimethanethiolate (L1), (1); 4-methylpyridine-2,6-dimethanethiolate (L2), (2)) were synthesized utilizing a single-step procedure, and their structures were characterized by X-ray crystallography. The aforementioned pentanuclear complexes possess an interesting propeller-like Cu(5)S(6) core where all Cu centers are three-coordinate. Electrospray ionization mass spectrometry (ESI-MS) investigation of the pentanuclear copper(I) thiolato clusters with added hetero-ligands demonstrated interesting ligand exchange behavior. The product distribution resulting from ligand exchange not only depended on the quantity of added ligand, but also was sensitive to the coordination ability of the ligand. The ESI-MS method used in this study can serve as a useful tool for probing exchange behavior in coordination metal complexes that cannot otherwise be determined by NMR., (Copyright © 2012 Elsevier Inc. All rights reserved.)

The AFM combined nanoindentation was performed to observe the ultrastructure of enamel rod from various section plans and positions while probing their mechanical and tribological properties of the area. The nanohardness and the elastic modulus of the head region of the enamel rods are significantly higher than that of the tail region and the axial-sectional plane. Both nanohardness and elastic modulus gradually decrease from enamel surface toward dentino-enamel junction. Such a variation correlates well with the decreasing trend of calcium composition from our element analysis. The friction coefficient and nanowear of the enamel showed an inversed trend to the hardness with respect to their relative topological position in the long axis of enamel rod toward DEJ. The relationship between the nanowear depth and the distance from the outer enamel surface to DEJ presented exponential function. The results presented clarify the basic nanomechanical and nanotribological properties of human enamel rods and provide a useful reference for the future development of dental restorative materials., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

We performed single-molecule telomere length and telomere fusion analysis in patients at different stages of chronic lymphocytic leukemia (CLL). Our work identified the shortest telomeres ever recorded in primary human tissue, reinforcing the concept that there is significant cell division in CLL. Furthermore, we provide direct evidence that critical telomere shortening, dysfunction, and fusion contribute to disease progression. The frequency of short telomeres and fusion events increased with advanced disease, but importantly these were also found in a subset of early-stage patient samples, indicating that these events can precede disease progression. Sequence analysis of fusion events isolated from persons with the shortest telomeres revealed limited numbers of repeats at the breakpoint, subtelomeric deletion, and microhomology. Array-comparative genome hybridization analysis of persons displaying evidence of telomere dysfunction revealed large-scale genomic rearrangements that were concentrated in the telomeric regions; this was not observed in samples with longer telomeres. The telomere dynamics observed in CLL B cells were indistinguishable from that observed in cells undergoing crisis in culture after abrogation of the p53 pathway. Taken together, our data support the concept that telomere erosion and subsequent telomere fusion are critical in the progression of CLL and that this paradigm may extend to other malignancies.

Chemical shift imaging (CSI) relies on a strong and homogeneous main field. Field homogeneity ensures adequate coherence between the precessions of individual spins within each voxel. Variation of field strength between different voxels causes geometric distortion and intensity variation in chemical shift images, resulting in errors when analyzing the spatial distribution of specific chemical compounds. A post-processing method, based on detection of the spectral peak of water and baseline subtraction with Lorentzian functions, was developed in this study to automatically correct spectra offsets caused by field inhomogeneity, thus enhancing the contrast of the chemical shift images. Because this method does not require prior field plot information, it offers advantages over existing correction methods. Furthermore, the method significantly reduces geometric distortion and enhances signals of chemical compounds even when the water suppression protocol was applied during the CSI data acquisition. The experimental results of the water and glucose phantoms showed a considerable reduction of artifacts in the spectroscopic images when this post-processing method was employed. The significance of this method was also demonstrated by an analysis of the spatial distributions of sugar and water contents in ripe and unripe bananas.

Bcl-2 family proteins play a critical role in the regulation of apoptosis in chronic lymphocytic leukemia (CLL). However, their association with established prognostic markers is unknown. In this study, we analyzed the expression of Bcl-2, Bax, and Mcl-1 in 185 CLL patients and evaluated their relationship with other prognostic markers, in vitro sensitivity to fludarabine, and clinical outcome. Mcl-1 expression was significantly correlated with stage of disease (P < .001), lymphocyte doubling time (P = .01), V(H) gene mutation status (P < .001), CD38 expression (P < .001), and ZAP-70 expression (P = .003). In addition, Mcl-1 and Mcl-1/Bax ratios showed strong correlations with in vitro resistance to fludarabine (P = .005 and P < .001, respectively). Furthermore, elevated Mcl-1 expression and Mcl-1/Bax ratios were predictive of time to first treatment in the whole cohort (P < .001 and P < .001, respectively) and in stage A patients only (P = .002 and P = .001, respectively). Taken together, our data show that Mcl-1 is a key controller of in vitro drug resistance and is an important regulator of disease progression and outcome in CLL. It therefore represents a promising therapeutic target in this incurable condition. The close correlation between Mcl-1 expression and V(H) gene mutation status, CD38 expression, and ZAP-70 expression offers a biologic explanation for their association with adverse prognosis.

In this study, we characterized nuclear factor kappaB (NF-kappaB) subunit DNA binding in chronic lymphocytic leukemia (CLL) samples and demonstrated heterogeneity in basal and inducible NF-kappaB. However, all cases showed higher basal NF-kappaB than normal B cells. Subunit analysis revealed DNA binding of p50, Rel A, and c-Rel in primary CLL cells, and Rel A DNA binding was associated with in vitro survival (P = .01) with high white cell count (P = .01) and shorter lymphocyte doubling time (P = .01). NF-kappaB induction after in vitro stimulation with anti-IgM was associated with increased in vitro survival (P < .001) and expression of the signaling molecule ZAP-70 (P = .003). Prompted by these data, we evaluated the novel parthenolide analog, LC-1, in 54 CLL patient samples. LC-1 induced apoptosis in all the samples tested with a mean LD(50) of 2.8 microM after 24 hours; normal B and T cells were significantly more resistant to its apoptotic effects (P < .001). Apoptosis was preceded by a marked loss of NF-kappaB DNA binding and sensitivity to LC-1 correlated with basal Rel A DNA binding (P = .03, r(2) = 0.15). Furthermore, Rel A DNA binding was inversely correlated with sensitivity to fludarabine (P = .001, r(2) = 0.3), implicating Rel A in fludarabine resistance. Taken together, these data indicate that Rel A represents an excellent therapeutic target for this incurable disease.

Although, the xanthate process has been shown to be an effective method for heavy metal removal from contaminated water, a heavy metal contaminated residual sludge is produced by the treatment process and the metal-xanthate sludge must be handled in accordance with the Taiwan EPA's waste disposal requirements. This work employed potassium ethyl xanthate (KEX) to remove copper ions from wastewater. The toxicity characteristic leaching procedure (TCLP) and semi-dynamic leaching test (SDLT) were used to determine the leaching potential and stability characteristics of the residual copper xanthate (Cu-EX) complexes. Results from metal removal experiments showed that KEX was suitable for the treatment of copper-containing wastewater over a wide copper concentration range (50, 100, 500, and 1000 mg/l) to the level that meets the Taiwan EPA's effluent regulations (3mg/l). The TCLP results of the residual Cu-EX complexes could meet the current regulations and thus the Cu-EX complexes could be treated as a non-hazardous material. Besides, the results of SDLT indicated that the complexes exhibited an excellent performance for stabilizing metals under acidic conditions, even slight chemical changes of the complexes occurred during extraction. The xanthate process, mixing KEX with copper-bearing solution to form Cu-EX precipitates, offered a comprehensive strategy for solving both copper-containing wastewater problems and subsequent sludge disposal requirements.

A conventional two-step freezing procedure was developed and optimized in order to cryopreserve oyster embryos. The effects of cooling rate, choice of cryoprotectant, and seeding temperature on the survival of late-stage oyster embryos were examined. When these factors were optimized, improved survival rates of 78 +/- 8 and 83 +/- 7% were achieved using 2 M Me(2)SO or glycerol, respectively, as the cryoprotectant. The experimental results indicate that oyster embryos survive after freezing over a broad range of cooling rates ranging from -0.5 to -16 degrees C/min. Me(2)SO, glycerol, propylene glycol, and ethylene glycol may be used as cryoprotectants for the cryopreservation of oyster embryos. Copyright 1999 Academic Press.

Cryomicroscopic observations were made of the volumetric behavior and kinetics of intracellular ice formation (IIF) in Drosophila melanogaster embryos in a modified cell culture medium (BD.20) or BD.20 + 2 M ethylene glycol. After rapid cooling to a given temperature, transient volumetric contraction of the embryos during the isothermal period was quantified by computerized video image analysis. Fitting these data to the numerical solution of the volume flux equation yielded estimates of the hydraulic permeability coefficient (Lp) for individual embryos at various subfreezing temperatures. Lp approximately followed an Arrhenius relation between -2 and -9 degrees C, with a value of 0.168 microns/(min-atm) extrapolated to 0 degrees C and an apparent activation energy delta E of 38.9 kcal/mol. IIF during an isothermal period occurred at random times whose characteristic temperature range and kinetics were affected by the presence of ethylene glycol. A stochastic process model developed to fit these data indicated the influence of both time-dependent and instantaneous components of IIF, presumed to be the result of seeding and heterogeneous nucleation, respectively. The presence of 2 M ethylene glycol depressed the characteristic temperature of instantaneous IIF by about 12 degrees C and reduced the rate constant for time-dependent IIF. Comparison with observed incidences of IIF yielded an estimate of the supercooling tolerance of 3 to 5 degrees C.

The osmometric behavior of Drosophila melanogaster embryos in permeabilized eggs was studied in a microscope diffusion chamber designed to impose a rapid change in osmotic environment at various temperatures. A numerical model of NaCl diffusion in the chamber predicted that radial variations in concentration arising from the presence of a thin film of solution at the top of the chamber were negligible. On the basis of transient electrical conductance measurements in the chamber, characteristic time constants for the change in concentration averaged over the chamber depth occupied by the eggs were 0.99, 0.77, and 0.60 min at 0, 10, and 20 degrees C, respectively. The chamber response was sufficiently rapid that the characteristic response of the embryo was not masked. Equilibrium volumetric behavior of the embryos indicated that they behaved as nearly ideal osmometers over the range of 0.256 to 2.000 osm, and followed the relation FVeq = 0.123C-1 + 0.541, where FVeq is equilibrium fractional volume and C is osmolality. Nonlinear regression of volumetric data during osmotic contraction yielded an average Lp of 0.722 micron/(min.atm) at 20 degrees C and an apparent activation energy delta E of 8.11 kcal/mol. The coefficients of variation in the Lp estimates among individual embryos were 38, 18, and 47% at 0, 10, and 20 degrees C, respectively. With the use of probability rules and a model for volumetric behavior during freezing, it was determined that the observed variability in Lp (assuming delta E is fixed) considerably broadens the transition range of cooling rates over which the predicted probability of intracellular ice formation goes from 0 to 1. However, experimental observations (21) show the actual transition range is even wider, indicating that there exist other important sources of variability which determine the event of ice formation in D. melanogaster embryos.

As a first step in developing a procedure for the cryopreservation of Drosophila melanogaster embryos, we have established a method for permeabilization of the eggcase and have initiated studies of the hydraulic conductivity of permeabilized embryos and the permeation of selected cryoprotective agents. The eggcase of D. melanogaster embryos has a wax layer that precludes any flux of water. A two-step procedure employing organic solvents was developed to effect removal of the wax layer with minimal deleterious effects on the embryos. Dechorionated embryos (Oregon-R strain P2, 12 to 13 hr old) were rinsed sequentially in isopropanol and hexane. After removal of solvent, embryos were held in a modified cell culture medium for further manipulation. This procedure routinely yielded 80 to 95% of the eggs permeabilized (as determined by osmotic contraction in 1 M sucrose) and 75 to 90% survival (incidence of hatching). Hydraulic conductivity of permeabilized embryos and permeation of cryoprotectants were determined using a microdiffusion chamber and computerized video microscopy. Regression analysis of the volumetric data from individual embryos yielded the Boyle-van't Hoff function FVeq = 0.124 (osm-1) + 0.541 with the standard deviations of slope and intercept (Vb) being 0.010 and 0.040, respectively. Permeabilized embryos exhibited ideal osmotic behavior over the range of 0.265 to 2.00 osm. The mean hydraulic conductivity coefficient (Lp) was 0.722 +/- 0.366 micron/(min.atm) at 20 degrees C, based on observations of contraction following a step change in concentration of Ringer's solution.(ABSTRACT TRUNCATED AT 250 WORDS)