Silibinin induces oral cancer cell apoptosis and reactive oxygen species generation by activating the JNK/c-Jun pathway

Background: Oral cancer is one of the most prevalent malignant tumors worldwide. Silibinin has been reported to exert therapeutic effects in various cancer models. However, its mechanism of action in oral cancer remains unclear. We aimed to examine the molecular processes underlying the effects of silibinin in oral cancer in vitro and in vivo as well as its potential anticancer effects. Next, we investigated the molecular processes underlying both in vitro and in vivo outcomes of silibinin treatment on oral cancer. Methods: To investigate the effects of silibinin on the growth of oral cancer cells, cell proliferation and anchorage-independent colony formation tests were conducted on YD10B and Ca9-22 oral cancer cells. The effects of silibinin on the migration and invasion of oral cancer cells were evaluated using transwell assays. Flow cytometry was used to examine apoptosis, cell cycle distribution, and accumulation of reactive oxygen species (ROS). The molecular mechanism underlying the anticancer effects of silibinin was explored using immunoblotting. The in vivo effects of silibinin were evaluated using a Ca9-22 xenograft mouse model. Results: Silibinin effectively suppressed YD10B and Ca9-22 cell proliferation and colony formation in a dose-dependent manner. Moreover, it induced cell cycle arrest in the G0/G1 phase, apoptosis, and ROS generation in these cells. Furthermore, silibinin inhibited the migration and invasion abilities of YD10B and Ca9-22 cells by regulating the expression of proteins involved in the epithelial-mesenchymal transition. Western blotting revealed that silibinin downregulated SOD1 and SOD2 and triggered the JNK/c-Jun pathway in oral cancer cells. Silibinin significantly inhibited xenograft tumor growth in nude mice, with no obvious toxicity. Conclusions: Silibinin considerably reduced the development of oral cancer cells by inducing apoptosis, G₀/G₁ arrest, ROS generation, and activation of the JNK/c-Jun pathway. Importantly, silibinin effectively suppressed xenograft tumor growth in nude mice. Our findings indicate that silibinin may be a promising option for the prevention or treatment of oral cancer.

The influence of androgynous streamers on consumers’ product preferences

Since the rapid development of network technology, the rise of live-streaming shopping platforms has followed. Some streamers influence consumers’ preferences for products through their gender role attributes, thus generating great commercial value. Based on attachment theory and using an experimental approach, this study explored the impact of streamers’ gender roles (single gender/androgyny) on consumers’ preferences through 2 studies. Study 1 shows the androgynous streamer elicits a higher product preference than the single-gender (masculine and feminine) streamer. Study 2 demonstrates the moderating effect of gender stereotypes through 2 experiments to construct clear boundary conditions for the main effect and the results show that regardless of whether the streamer is male or female when individuals have a high gender stereotype, the single-gender streamer leads to a higher product preference than the androgynous streamer. When individuals have a low gender stereotype, the androgynous streamer promotes a higher product preference than the single-gender streamer.

Clinical characteristics of pneumonia patients of long course of illness infected with SARS-CoV-2

Epidemiological and clinical characteristics of patients with COVID-19 have been reported in the last two years. A few studies reported clinical course of illness of median 22 days, including viral shedding of median 20 days, but there are several cases with a longer time of viral shedding. In this study, we included four cases with a longer illness course of more than 40 days who had been discharged or still in hospital by March 15, 2020. Demographic, clinical treatment, and laboratory data, including serial samples for viral RNA detection, were extracted from electronic medical records. We described the epidemiological and clinical characteristics and the course of viral shedding. Two patients had comorbidity, one with hypertension and the other with diabetes. We found smoking was not an independent risk factor. D-dimer maybe related to the severity of illness but not to the course of the illness. Nucleic acid detection suggested that maybe more sampling sites represented more virus replication sites and longer course of illness. In this study we found some non-critical severe relatively young patients whose character was different from former studies described to provide a basis for reference to assess the risk of transmission and the isolation duration of patients.

AB0110 TRANSCRIPTOMICS-BASED INVESTIGATION OF THE MECHANISM OF ANKYLOSING SPONDYLITIS WITH UVEITIS

Background

Spondyloarthritis is a large group of autoimmune diseases that are associated with HLA-B27. Among them, Ankylosing spondylitis is a typical representative of these diseases. In addition to spine and joint involvement, AS has many extra-articular manifestations, among which uveitis is one of the most common extra-articular manifestations of AS.[1]Untreated or inappropriate treatment can lead to serious consequences such as blindness. However, there are few studies on the mechanisms of AS-related uveitis, and the pathogenesis of AS-related uveitis is not fully understood, so there is no way to prevent it.

Objectives

We performed a whole-blood gene expression profiling and then analyzed gene expression differences between AS-associated uveitis patients and normal controls by bioinformatics methods. Protein–protein interaction network was constructed to predict the relationship among the products of the differentially expression genes (DEGs). Furthermore, module mining and function annotation were applied to assess the interaction network of DEGs.The aim is to find predictive biomarkers for AS-associated uveitis, to further discuss the pathogenesis of AS-associated uveitis in depth, and to provide a reference for clinical precision treatment.

Methods

This microarray-based discovery study used samples from three patients with AS,classified according to the New York criteria,four patients with AS-associated uveitis, and three gender- and age-matched controls. Total RNA was extracted from whole blood samples and enriched for mRNA after DNA digestion using DNase, and then constructed cDNA libraries were quality-checked with an Agilent 2100 Bioanalyzer and sequenced using an Illumina HiSeq TM 2500 sequencer.The data were normalized and initially screened for differential genes using the DESeq R package in R 4.1.0 Prediction of relationships between products of differentially expressed genes (DEGs) using String database prediction and construction of protein-protein interaction networks in Cytoscape. GO with KEGG analysis of differential genes using ClueGO and CluePedia. Screening for hub genes associated with AS-associated uveitis using cytoHubba.

Results

We initially screened 14607 differential genes, from which 112 significantly differential genes with p-values<0.05 and |log2FC|>2 were selected. Among them, 82 were up-regulated genes and 30 were down-regulated genes. Sixty-six relationships between 49 nodes were shown in the PPI network interactions graph constructed from the String database results.The results of GO analysis showed that most genes were involved in biological processes related to immune response, such as positive regulation of inflammatory response, integrated stress response signaling and toll-like receptor 4 signaling pathway. The molecular functions were mainly focused on chemokine receptor binding. the results of KEGG analysis showed that the gene products were mainly involved in cytokine-cytokine receptor interaction, IL-17 signaling pathway. The target genes screened included CXCL8 CXCL2 NFKBIZ NFKBIA IL11 IL1A,all of which have adequate immune response effects(Figure 1)

Figure 1.

Using the EPC algorithm in cytoHubba to screen hub genes, the graph shows the top 10 scoring genes, with different colors representing higher scores.

Conclusion

We have identified a series of genes associated with immunity in this study.These DEGs may provide a basis for insight into the pathogenesis of AS-associated uveitis. Further experimental studies are needed to confirm our hypothesis.

References

[1]Wenker K. J. & Quint J. M. (2021). Ankylosing Spondylitis. In StatPearls. StatPearls Publishing

*Corresponding author

Jing Zhu1* Bo Gong2*

1Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Department of Rheumatology and Immunology Chengdu China

2Department of Health Management,Sichuan Academy of Medical Sciences&Sichuan Provincial People’s Hospital,University of Electronic Science and Technology of China Chengdu China

Disclosure of Interests

None declared

[6]-Gingerol Suppresses Oral Cancer Cell Growth by Inducing the Activation of AMPK and Suppressing the AKT/mTOR Signaling Pathway

BACKGROUND/AIM

[6]-Gingerol, a compound extracted from ginger, has been studied for its therapeutic potential in various types of cancers. However, its effects on oral cancer remain largely unknown. Here, we aimed to investigate the potential anticancer activity and underlying mechanisms of [6]-gingerol in oral cancer cells.

MATERIALS AND METHODS

We analyzed the antigrowth effects of [6]-gingerol in oral cancer cell lines by cell proliferation, colony formation, migration, and invasion assays. We detected cell cycle and apoptosis with flow cytometry and further explored the mechanisms of action by immunoblotting.

RESULTS

[6]-Gingerol significantly inhibited oral cancer cell growth by inducing apoptosis and cell cycle G2/M phase arrest. [6]-Gingerol also inhibited oral cancer cell migration and invasion by up-regulating E-cadherin and down-regulating N-cadherin and vimentin. Moreover, [6]-gingerol induced the activation of AMPK and suppressed the AKT/mTOR signaling pathway in YD10B and Ca9-22 cells.

CONCLUSION

[6]-Gingerol exerts anticancer activity by activating AMPK and suppressing the AKT/mTOR signaling pathway in oral cancer cells. Our findings highlight the potential of [6]-gingerol as a therapeutic drug for oral cancer treatment.

20(S)-Ginsenoside Rh2 Suppresses Oral Cancer Cell Growth by Inhibiting the Src-Raf-ERK Signaling Pathway

BACKGROUND

20(S)-Ginsenoside Rh2 (G-Rh2) has demonstrated therapeutic effects in many types of cancers. We aimed to investigate the potential anticancer activity and underlying mechanisms of G-Rh2 in oral cancer cells.

MATERIALS AND METHODS

The antigrowth effect of G-Rh2 in oral cancer cells was stimulated by cell proliferation, soft agar colony formation, and migration and invasion assay. The cell cycle and apoptosis were detected by flow cytometry. The underlying mechanism of G-Rh2 in oral cancer cells was explored by immunoblotting.

RESULTS

G-Rh2 significantly inhibited oral cancer cell growth by inducing apoptosis and cell cycle G₀/G₁-phase arrest. G-Rh2 inhibited oral cancer cell migration and invasion through regulation of epithelial-mesenchymal transition (EMT)-related proteins. G-Rh2 inhibited the Src/Raf/ERK signaling pathway in YD10B and Ca9-22 cells.

CONCLUSION

G-Rh2 exerted anticancer activity in vitro by inhibiting the Src/Raf/ERK signaling pathway in oral cancer. G-Rh2 is a potential therapeutic drug for oral cancer treatment.

Antibodies in the breast milk of a maternal woman with COVID-19

A maternal woman was positive for SARS-CoV-2 tested in throat swabs but negative tested in other body fluids, and she had IgG and IgA detected in breast milk. Her infant negative for SARS-CoV-2 at birth had elevated IgG in serum but quickly decayed. These findings suggest that breastfeeding might have the potential benefit to the neonates.

Preclinical proof-of-concept study: antisense-mediated knockdown of CALM as a therapeutic strategy for calmodulinopathy

Background

Calmodulin (CaM) is a ubiquitous Ca2+ sensor molecule encoded by three distinct calmodulin genes, CALM1–3, and has an important role for cardiac ion channel function. Recently, heterozygous missense mutations in CALM genes were reported to cause a new category of life-threatening genetic arrhythmias such as long-QT syndrome (LQTS) and catecholaminergic polymorphic ventricular tachycardia (CPVT), which is called as “calmodulinopathy”. The patients with calmodulinopathy show poor prognosis and there is no effective treatment for them.

Purpose

Considering the dominant-negative effect of mutant calmodulin proteins produced by heterozygous missense mutations in CALMs, we aimed to prove the concept of antisense-based therapy to treat calmodulinopathy using human iPS cell-derived cardiomyocyte (hiPSC-CM) model.

Methods

We designed multiple locked nucleic acid (LNA) gapmer-antisense oligonucleotides (ASOs) targeting CALM2 and analyzed the silencing efficiency and toxicity in cultured cells to select the most potent ASO. Using CMs differentiated from hiPSCs which were generated form a 12-year-old boy with LQTS carrying a heterozygous CALM2-N98S mutation, CALM2 expression and action potentials (APs) were analyzed to evaluate the efficacy of ASOs.

Results

We identified several ASOs which reduced CALM2 expression without affecting cell viability in human cultured cells (HepG2) (ASO 50 nM, n=2; Figure 1A). Considering further experiments in vivo mouse model, we investigated the CALM2 silencing activity in mouse cultured cells (3T3-L1) without transfection (free-uptake) (ASO 1 μM, n=2; †ASOs have homologous sequence between human and mouse; Figure B). After free-uptake CALM2 silencing analysis in 3T3-L1 cells, we identified that ASO #2 has the most potent CALM2 silencing activity and low cytotoxicity (Figure 1B). ASO #2 effectively reduced CALM2 expression even in hiPSC-CMs (ASO(−): n=3, lipofection: n=4, free-uptake: n=3; P&lt;0.05; Figure 1C). In action potential recordings, we demonstrated that ASO #2 ameliorated prolonged AP durations (APD90) in N98S-hiPSC-CMs at 0.5 Hz pacing (ASO(−): 666±123 ms (n=7), lipofection: 329±21 ms (n=8), free-uptake: 388±34 ms (n=12); P&lt;0.05; Figure 1D).

Conclusion

Our results using patient-derived hiPSC-CM model suggest that ASO-based therapy might be a promising strategy for the treatment of calmodulinopathy.

Figure 1

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): Nissan Chemical Corporation

Cognition-based hybrid path planning for autonomous underwater vehicle target following

Intelligent path planning is one of the key techniques for autonomous underwater vehicles for the purpose of target detection, environmental survey and so on. In order to realize automatic motion plan, an intelligent cognitive architecture for autonomous underwater vehicle motion planning has been proposed to realize complicated target detection and mobile target following in the disturbance environment. A novel adaptive ant colony optimization and particle swarm optimization fusion-based fuzzy rules optimization algorithm has been proposed to generate optimized fuzzy rules. Through this optimization algorithm, the preliminary fuzzy rules can be optimized to realize intelligent motion planning for complicated operation tasks. Experiments of channel following for wall detection and mobile target following in the oceanic environment have verified the validity of path planning method in the implementation of detection and operation tasks.

The presence of multiple NS5A RASs is associated with the outcome of sofosbuvir and ledipasvir therapy in NS5A inhibitor-naïve patients with chronic HCV genotype 1b infection in a real-world cohort

It is unclear whether multiple nonstructural (NS) 5A resistance-associated substitutions (RASs) correlate with the outcome of sofosbuvir (SOF) and ledipasvir (LDV) therapy. We investigated the effects of multiple NS5A RASs in NS5A inhibitor-naïve patients with chronic hepatitis C virus genotype 1b infection treated with SOF/LDV. In 313 patients treated with SOF/LDV, we assessed the effects of multiple NS5A RASs on the sustained virological response (SVR). RASs at L28, R30, L31, Q54, P58, Q62, A92, and Y93 in the NS5A region were examined by direct sequencing. The prevalence of RASs was as follows: 2.6% at L28, 8.7% at R30, 6.1% at L31, 48.7% at Q54, 9.9% at P58, 9.9% at Q62, 5.1% at A92, 13.8% at Y93, and 19.2% at L31 or Y93. A total of 133 patients had no RASs. SVR was achieved in 98.7% of the patients. SVR rates significantly differed between patients with and without the L31 or Y93 RAS (93.0% [53/57] vs 100% [250/250], P = .0011). In addition, among patients with the L31 or Y93 RAS, 29.8%, 45.6% and 24.6% had one, two and three or more NS5A RASs, respectively. The SVR rate was significantly lower in patients with the L31 or Y93 RAS with more than three NS5A RASs compared to those with fewer than three NS5A RASs (71.4% [10/14] vs 100% [43/43], P = .0025). Although the prevalence of multiple NS5A RASs at baseline was low in NS5A inhibitor-naïve patients, the presence of multiple NS5A RASs was associated with the effectiveness of SOF/LDV therapy.

Autonomous underwater vehicle precise motion control for target following with model uncertainty

Target following plays an important role in oceanic detection and target capturing for autonomous underwater vehicles. Due to the model nonlinearity and external disturbance, the dynamic model of a portable autonomous underwater vehicle was usually established with parameter uncertainties. In this article, a petri-based recurrent type 2 fuzzy neural network has been built to approximate the unknown autonomous underwater vehicle dynamics. The type 2 fuzzy logic system has been applied to the network to improve the approximation accuracy for systematic nonlinearity, and the petri layer in the network can improve estimation speed and reduce energy consumption. A petri-based recurrent type 2 fuzzy neural network–based adaptive robust controller has been proposed for target tracking. In the offshore experiments, the proposed controller has not only realized stable position and pose control but also successfully followed mobile target on the surface. In the tank underwater experiments, the pipeline target has been successfully followed to further verify the controller performance.

Effects of different gastrointestinal surgical approaches on pancreatic β-cell function in type 2 diabetic patients with BMIs<30

OBJECTIVE

Gastrointestinal surgery has been performed for many years to achieve durable and effective treatments of type 2 diabetes mellitus (T2DM). This study determined the effects of different surgical operations on pancreatic β-cell function in patients with T2DM with BMIs<30 kg/m(2).

DESIGN AND PATIENTS

A total of 46 patients with diabetes and BMIs<30 kg/m(2) underwent gastrointestinal surgery; 23 patients underwent Roux-en-Y gastric bypass (RYGB), and 23 patients underwent Billroth Ι gastrectomy (BΙG). Oral glucose tolerance tests were used to evaluate pancreatic β cell function. Serum insulin was measured by enzyme-linked immunosorbent assay (ELISA), and blood glucose was detected with the glucose oxidase method. HOMA-IR and HOMA-β were evaluated with the HOMA equation.

RESULTS

The T2DM remission rates were 21.7% (5/23) in the BΙG group and 82.6% (19/23) in the RYGB group. There was a significant difference in the improvements in postoperative glycosylated hemoglobin A1c (GHbA1c) and glycated hemoglobin A1 (GHbA1) between the BΙG and RYGB groups (P=0.001, P=0.002). OGTT revealed that both fasting blood glucose (FBG) and blood glucose at the designated time points after glucose loading were significantly lower in the RYGB group than in the BΙG group. Insulin levels (at 30 and 60 min), insulin release indices (at 30 and 60 min), HOMA-β and ΔI30/ΔG30 were significantly higher in the RYGB group than in the BΙG group (P<0.05).

CONCLUSIONS

Patients with BMIs<30 kg/m(2) who underwent RYGB surgery exhibited significantly greater improvements or resolutions of T2DM and significantly better recoveries of β-cells function than did those in the BΙG group.

A Fault-tolerable Control Scheme for an Open-frame Underwater Vehicle

Open-frame is one of the major types of structures of Remote Operated Vehicles (ROV) because it is easy to place sensors and operations equipment onboard. Firstly, this paper designed a petri-based recurrent neural network (PRFNN) to improve the robustness with response to nonlinear characteristics and strong disturbance of an open-frame underwater vehicle. A threshold has been set in the third layer to reduce the amount of calculations and regulate the training process. The whole network convergence is guaranteed with the selection of learning rate parameters. Secondly, a fault tolerance control (FTC) scheme is established with the optimal allocation of thrust. Infinity-norm optimization has been combined with 2-norm optimization to construct a bi-criteria primal-dual neural network FTC scheme. In the experiments and simulation, PRFNN outperformed fuzzy neural networks in motion control, while bi-criteria optimization outperformed 2-norm optimization in FTC, which demonstrates that the FTC controller can improve computational efficiency, reduce control errors, and implement fault tolerable thrust allocation.

The DUF59 family gene AE7 acts in the cytosolic iron-sulfur cluster assembly pathway to maintain nuclear genome integrity in Arabidopsis

Eukaryotic organisms have evolved a set of strategies to safeguard genome integrity, but the underlying mechanisms remain poorly understood. Here, we report that asymmetric leaves1/2 enhancer7 (AE7), an Arabidopsis thaliana gene encoding a protein in the evolutionarily conserved Domain of Unknown Function 59 family, participates in the cytosolic iron-sulfur (Fe-S) cluster assembly (CIA) pathway to maintain genome integrity. The severe ae7-2 allele is embryo lethal, whereas plants with the weak ae7 (ae7-1) allele are viable but exhibit highly accumulated DNA damage that activates the DNA damage response to arrest the cell cycle. AE7 is part of a protein complex with CIA1, NAR1, and MET18, which are highly conserved in eukaryotes and are involved in the biogenesis of cytosolic and nuclear Fe-S proteins. ae7-1 plants have lower activities of the cytosolic [4Fe-4S] enzyme aconitase and the nuclear [4Fe-4S] enzyme DNA glycosylase ROS1. Additionally, mutations in the gene encoding the mitochondrial ATP binding cassette transporter ATM3/ABCB25, which is required for the activity of cytosolic Fe-S enzymes in Arabidopsis, also result in defective genome integrity similar to that of ae7-1. These results indicate that AE7 is a central member of the CIA pathway, linking plant mitochondria to nuclear genome integrity through assembly of Fe-S proteins.

Hypermethylation of tumor suppressor genes BRCA1, p16 and 14-3-3sigma in serum of sporadic breast cancer patients

BACKGROUND

We investigated the hypermethylation status in serum of sporadic breast cancer patients.

MATERIAL AND METHODS

The hypermethylation status of BRCA1, p16 and 14-3-3sigma in cancerous tissues and the paired serum of 38 sporadic breast cancer patients was examined by methylation-specific PCR (MSP) assay. Normal and benign tissue and serum control DNA were also examined to determine the specificity of hypermethylation.

RESULTS

Hypermethylation of 1 or more genes was found in 36/38 (95%) of sporadic breast cancers. BRCA1 was hypermethylated in 14/38 (37%), p16 in 13/38 (34%), and 14- 3-3sigma in 33/38 (87%) of cancerous tissues. 71% of the corresponding serum DNA was positive for hypermethylation, including all histological types, stages and grades. No methylated products of BRCA1, p16 and 14-3-3sigma were observed in serum DNA from healthy women and patients with benign tissue specimens. A gene unmethylated in the tumor DNA was always found to be unmethylated in matched serum DNA.

CONCLUSIONS

Hypermethylation of BRCA1, p16 and 14-3-3sigma is present in all histologic types, stages and grades in sporadic breast cancer and can be detected in serum DNA. It signifies that serum-based hypermethylation screening may enhance early detection of sporadic breast cancer.

Rescue of a telomere length defect of Nijmegen breakage syndrome cells requires NBS and telomerase catalytic subunit

Nijmegen breakage syndrome (NBS) is a rare human disease displaying chromosome instability, radiosensitivity, cancer predisposition, immunodeficiency, and other defects [1, 2]. NBS is complexed with MRE11 and RAD50 in a DNA repair complex [3-5] and is localized to telomere ends in association with TRF proteins [6, 7]. We show that blood cells from NBS patients have shortened telomere DNA ends. Likewise, cultured NBS fibroblasts that exhibit a premature growth cessation were observed with correspondingly shortened telomeres. Introduction of the catalytic subunit of telomerase, TERT, was alone sufficient to increase the proliferative capacity of NBS fibroblasts. However, NBS, but not TERT, restores the capacity of NBS cells to survive gamma irradiation damage. Strikingly, NBS promotes telomere elongation in conjunction with TERT in NBS fibroblasts. These results suggest that NBS is a required accessory protein for telomere extension. Since NBS patients have shortened telomeres, these defects may contribute to the chromosome instability and disease associated with NBS patients.

[Analysis on infrared spectrum of human body gallstone with comparative method]

The infrared spectra (IRS) are measured for chemical composition of series gallstones. The infrared spectra (IRS) of the gallstone are compared with IRS of standard compound sample. The typical IRS are divided into 6 genera in component analysis of gallstone according to the principal characteristic peak: cholesterol, calcium bilirubin, calcium stearate, calcium carbonate, hydroxyl carbonate phosphatic rock and mixture. The gallstones are correlatively divided into 6 genera of gallstones or 2 genera-cholesterol and calcium salt gallstones according to whether containing calcium salt.

[Characteristics on ultraviolet absorption spectrum from difference in temperature and electron transition types of compounds]

The paper states a measuring method about Ultraviolet absorption spectrum from difference in temperature (UVSDT). The UVSDT of chemical compounds have been obtained with UV-240 ultraviolet spectrophotometer. The results show that the characteristic of UVSDT is related to electronic transition type of molecule. The long wave side shifts to long wave, when difference in temperature (delta t) accretes, peak high increases, bathochromic shift augments for UVSDT of n-sigma* electron transition. The UVSDT of n-pi* electron transition has two peak (one positive peak and one negative peak), when delta t accretes, the positive peak up increases, the negative peak down increases. The UVSDT of pi-pi* electron transition become negative peak, when delta t accretes, the negative peak down increases, the location of peak not moves.

Ca2+-induced distance change between points on actin and troponin in skeletal muscle thin filaments estimated by fluorescence energy transfer spectroscopy

Fluorescence resonance energy transfer spectroscopy has been used to study the spatial relationships between probes attached to actin and troponin in the reconstituted skeletal muscle thin filament in the presence and absence of Ca2+ ions. Gln-41 and the nucleotide-binding site of actin were selectively labeled with the acceptor probe: fluorescein cadaverine and 2'(or 3')-O-(2,4,6-trinitrophenyl)adenosine 5'-diphosphate (TNP-ADP), respectively. Troponin was selectively labeled at positions 9 or 133 of troponin-I and 98 of troponin-C with a donor probe; 5-(2-iodoacetylaminoethyl)aminonaphthalene 1-sulfonic acid (IAEDANS). The distances between probes attached to position 133 of TnI and Gln-41 or the nucleotide site of actin were determined to be 51.6+/-1.2 and 42.7+/-0.9 A respectively in the presence of Ca2+, and these distances decreased by 11.5 and 9.3 A respectively in the absence of Ca2+ ions. The distances between the probes attached to position 9 of TnI and Gln-41 or the nucleotide site of actin were determined to be 59.1+/-2.0 or 49.3+/-1.5 A respectively in the presence of Ca2+, and the distances decreased by 5.3 or 3.7 A in the absence of Ca2+. The distances between probes attached to position 98 of TnC and Gln-41 or the nucleotide site of actin were determined to be 55.1+/-1.7 and 57+/-5 A in the presence of Ca2+ and the distances increased slightly by approximately 1 A in the absence of Ca2+. The results suggest that the C-terminal domain of troponin I moves to the outer domain of actin during inhibition, while the C-terminal domain of TnC does not move much.

The in vivo effect of the tumor promoter 12-O-tetradecanoylphorbol-13-acetate on N-methyl-N-nitrosourea-induced apoptosis in mouse hair follicles

This study assessed the in vivo relationship between apoptosis induced by the tumor initiator N-methyl-N-nitrosourea (MNU) and action of the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) in mouse hair follicle matrix cells. Mouse hair follicles were stimulated to grow hair synchronously by plucking resting hairs and MNU was applied to the plucked skin as the apoptosis inducer. The effects of TPA on MNU-induced apoptosis, when given at different intervals before or after MNU treatment, were examined. Changes in the percentage of apoptotic cells among total hair matrix cells after TPA treatment were measured. A significant suppression in levels of MNU-induced apoptosis was observed in the animals receiving TPA 1 to 6 hr following the induction. Administration of TPA before MNU caused a reduction in numbers of apoptotic cells over the control groups, but the differences were not significant. Determination of the diurnal variation in apoptotic levels in vehicle-treated mouse hair follicles revealed a relatively constant baseline pattern, suggesting that the above apoptotic responses to MNU and TPA were not affected by the background levels of apoptosis. The findings provided in vivo evidence which would support the hypothesis that TPA promotes tumorigenesis by preventing carcinogen-initiated cells from undergoing apoptotic death.

A multicenter comparison of adhesion, preference, tolerability, and safety characteristics of two transdermal nitroglycerin delivery systems: Transderm-Nitro and Deponit

One hundred forty-two patients with stable angina were enrolled in a four-week, multicenter, office-based study to compare the adhesion properties, patient preference, and tolerability of two commercially available transdermal nitroglycerin patches. Data from 139 patients were analyzed. Each patient simultaneously wore one 5-mg Transderm-Nitro (TDN) patch and one 5-mg Deponit (DPT) patch. Patients daily recorded the following information in a diary format: number of angina attacks, frequency of sublingual nitroglycerin use, patch adhesion, and problems at the adhesion site or other medical problems. At the end of the study, patients rated their patch preferences based on ease of application and removal, ease of removing backing, overall adhesion, and adhesion under specific conditions, such as showering, swimming, exercise, hot weather, high humidity, and perspiration. They also specified which patch they would choose for their next prescription. Differences in adhesion properties (P less than 0.0001) and tolerability at the site of application favored TDN over DPT. In addition, significantly more patients (P less than 0.0001) specified TDN as their next prescription choice (83% vs 11%).

Disposition of N-methyl-[ring-3,5-3H]tyramine in rabbits and mice

After iv bolus injection of N-methyl-[ring-3,5-3H] tyramine ([3H]MT) 14.8 MBq/kg in rabbits, the plasma concentration-time data was found to be in accordance with the 2-compartment model. The pharmacokinetic parameters were: T1/2 alpha = 0.3 min, T1/2 beta = 5.6 min, K12 = 0.69/min, K21 = 0.21/min, K10 = 1.6/min, VC = 0.4 L/kg, Cl = 0.62 L/kg.min-1. [3H]MT was taken up by organs rapidly and extensively. Two min after administration, a large amount of radioactivity was detected in every organ sampled. The highest amounts were in the kidney and liver, followed by lung, small intestine, heart, skeletal muscle, spleen, brain and fat. The drug was metabolized extremely fast in vivo. The metabolites were found in the plasma chromatogram just 0.5 min after dosing, while over 80% were found in the urine within 1 h. After a 1 h collecting period, the radioactivity recovered in the urine amounted to 79% of the injected dose. By the end of a 6 h collection, almost no drug was detected in the body.

Technetium-99m stannous pyrophosphate myocardial scintigraphy after cardiopulmonary resuscitation with cardioversion

Thirty consecutive patients underwent technetium-99m stannous pyrophosphate myocardial scintigraphy 48--72 hours after successful cardiopulmonary resuscitation and direct current cardioversion. Five patients with transmural myocardial infarctions by ECG and enzyme determinations were correctly identified by scintigraphy. Myocardial scans were positive in five of nine patients with nontransmural infarction. Of 16 patients without evidence of myocardial infarction, only two (13%) had false-positive myocardial scans. The overall accuracy of imaging in this series was 80%. We conclude that false-positive scans after cardiopulmonary resuscitation with electrical cardioversion are infrequent, and do not significantly detract from the value of myocardial scintigraphy in the diagnosis of myocardial infarction.