DNAL7, a new allele of NAL11, has major pleiotropic effects on rice architecture

MAIN CONCLUSION

dnal7, a novel allelic variant of the OsHSP40, affects rice plant architecture and grain yield by coordinating auxins, cytokinins, and gibberellic acids. Plant height and leaf morphology are the most important traits of the ideal plant architecture (IPA), and discovering related genes is critical for breeding high-yield rice. Here, a dwarf and narrow leaf 7 (dnal7) mutant was identified from a γ-ray treated mutant population, which exhibits pleiotropic effects, including dwarfing, narrow leaves, small seeds, and low grain yield per plant compared to the wild type (WT). Histological analysis showed that the number of veins and the distance between adjacent small veins (SVs) were significantly reduced compared to the WT, indicating that DNAL7 controls leaf size by regulating the formation of veins. Map-based cloning and transgenic complementation revealed that DNAL7 is allelic to NAL11, which encodes OsHSP40, and the deletion of 2 codons in dnal7 destroyed the His-Pro-Asp (HPD) motif of OsHSP40. In addition, expression of DNAL7 in both WT and dnal7 gradually increased with the increase of temperature in the range of 27-31 °C. Heat stress significantly affected the seedling height and leaf width of the dnal7 mutant. A comparative transcriptome analysis of WT and dnal7 revealed that DNAL7 influenced multiple metabolic pathways, including plant hormone signal transduction, carbon metabolism, and biosynthesis of amino acids. Furthermore, the contents of the cytokinins in leaf blades were much higher in dnal7 than in the WT, whereas the contents of auxins were lower in dnal7. The contents of bioactive gibberellic acids (GAs) including GA1, GA3, and GA4 in shoots were decreased in dnal7. Thus, DNAL7 regulates rice plant architecture by coordinating the balance of auxins, cytokinins, and GAs. These results indicate that OsHSP40 is a pleiotropic gene, which plays an important role in improving rice yield and plant architecture.

Development of InDel markers for Oryza sativa ssp. javanica based on whole-genome resequencing

Oryza sativa ssp. javanica rice varieties exhibit a wide variation in the phenotypes of several important agronomic traits, including grain quality, grain shape, plant architecture, disease resistance, and high adaption to an unfavorable environment, indicating a great potential for rice improvement. DNA molecular markers are basic and critical tools in genetic analysis and gene mining. However, only a few whole-genome variation analyses have been performed in Oryza sativa ssp. Javanica (tropical japonica rice), and this has hampered the utilization of such an important resource. In this study, the length of insertions/deletions variation greater larger than 10 bp from 10 Oryza sativa ssp. indica rice and 10 Oryza sativa ssp. tropical japonica rice were extracted by using the Nipponbare genome as a reference. A total of 118 primer pairs which were almost evenly distributed on each chromosome corresponding to the loci of InDels were designed by the Primer 5 program. We confirmed 85 InDel markers from 60 rice varieties, including indica and tropical japonica, by running polyacrylamide gels. The InDel markers function like SSRs in identifying hybrids, calculating genetic distance, constructing the genetic linkage map, and gene mining. The InDel markers developed in this study might help in genetic studies and to investigate the tropical japonica rice varieties.

Whole Genome Resequencing of 20 Accessions of Rice Landraces Reveals Javanica Genomic Structure Variation and Allelic Genotypes of a Grain Weight Gene TGW2

The landraces preserved by indigenous worldwide exhibited larger variation in the phenotypes and adaption to different environments, which suggests that they comprise rich resources and can be served as a gene pool for rice improvement. Despite extensive studies on cultivated rice, the variations and relationships between landraces and modern cultivated rice remain unclear. In this study, a total of 20 varieties that include 10 Oryza javanica collected from different countries worldwide and 10 Oryza indica from China were genotyped and yielded a sum of 99.9-Gb resequencing raw data. With the genomic sequence of the japonica cultivar Nipponbare as a reference, the following genetic features of single-nucleotide polymorphism (SNP) ranged from 861,177 to 1,044,617, insertion-deletion polymorphisms (InDels) ranged from 164,018 to 211,135, and structural variation (SV) ranged from 3,313 to 4,959 were identified in Oryza javanica. Variation between the two subspecies was also determined that 584,104 SNPs, 75,351 InDels, 104,606 SNPs, and 19,872 InDels specific to Oryza indica and Oryza javanica, respectively. Furthermore, Gene Ontology (GO) and KEGG of Oryza javanica-specific SNP-related genes revealed that they participated in DNA metabolic process, DNA replication, and DNA integration. The sequence variation and candidate grain shape-related gene TGW2 were identified through Fst and sweep selective analysis. Hap4 of TGW2 is performed better than others. The whole genome sequence data and genetic variation information illustrated in this study will serve as an important gene pool for molecular breeding and facilitate genetic analysis of Oryza javanica varieties.

[Survey on tobacco use and associated factors in population in Shandong province, 2016-2017]

Objective: To understand the status of tobacco use and related influencing factors in population in Shandong province. Methods: Stratified multi-stage cluster sampling was used to select respondents from 216 villages (communities) of 36 districts (counties) in Shandong province. Influencing factors on smoking were analyzed by logistic regression model. Results: The adequate sample size was 6 271 participants. After complex weighted, the current smoking prevalence was 23.93%,45.58% in males and 1.18% in females. The Public's smoking rates varied widely among different groups in the population. 45-64 age group had the highest smoking rate (25.07%). Smoking rates were substantially different in education levels, with the highest in junior high school (28.94%). The rate was higher in the rural area (24.98%) than that in the urban areas (23.08%). The average daily smoking rate was 20.23%. The average age of initiating smoking was 21.21 years. The average daily cigarette intake was 16.31 cigarettes. Among all the former and current smokers, the quitting rate was 20.79%. Multiple logistic regression model analysis showed that gender, age, occupation, region, and health knowledge score were correlated with smoking behavior. The current smoking rate of men was much higher than that of women (OR=49.625, 95%CI: 37.832-65.093). The current smoking rate in 45-64 age group was higher than that in the 15-24 age group (OR=1.830, 95%CI: 1.048-3.194). The current smoking rate of medical (OR=0.403, 95%CI: 0.187-0.866) and retired personnel (OR=0.648, 95%CI: 0.481-0.873) were lower than those engaging in agriculture, forestry, animal husbandry and the fishery ,respectively. The prevalence of residents living in the central part showed lower rate on current smoking than that in the eastern region (OR=0.724, 95%CI: 0.606-0.865). The current smoking prevalence of smoke hazard in 1-3 score group was higher than that in the group with 4-6 score (OR=1.432, 95%CI: 1.240-1.654). Conclusions: Smoking rate in adults in Shandong remained stable and at a high level. Comprehensive intervention measures such as tobacco control and health education should be carried out to reduce the smoking rate.

Repeats in mitochondrial and chloroplast genomes characterize the ecotypes of the Oryza

Mitochondria and chloroplast are very important organelles for organism, participating in basic life activity. Their genomes contain many repeats which can lead to a variation of genome structure. Oryza is an important genus for human beings' nutrition. Several mitochondrial and chloroplast genomes of Oryza have been sequenced, which help us to insight the distribution and evolution of the repeats in Oryza species. In this paper, we compared six mitochondrial and 13 chloroplast genomes of Oryza and found that the structures of mitochondrial genomes were more diverse than chloroplast genomes. Since repeats can change the structure of the genome, resulting in the structural diversity of the genome, we analyzed all repeats and found 31 repeats in mitochondrial and 13 repeats in chloroplast genomes. Further, we developed 21 pairs of MRS molecular markers and 12 pairs of CRS molecular markers based on mitochondrial repeats and chloroplast repeats, respectively. These molecular markers can be used to detect the repeat-mediated recombination in Oryza mitochondrial and chloroplast genomes by PCR or fluorescence quantification.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11032-020-01198-6.

Quantitative Trait Loci Mapping of Mineral Element Contents in Brown Rice Using Backcross Inbred Lines Derived From Oryza longistaminata

Mineral elements play an extremely important role in human health, and are worthy of study in rice grain. Wild rice is an important gene pool for rice improvement including grain yield, disease, and pest resistance as well as mineral elements. In this study, we identified 33 quantitative trait loci (QTL) for Fe, Zn, Se, Cd, Hg, and As contents in wild rice Oryza longistaminata. Of which, 29 QTLs were the first report, and 12 QTLs were overlapped to form five clusters as qSe1/qCd1 on chromosome 1, qCd4.2/qHg4 on chromosome 4, qFe5.2/qZn5.2 on chromosome 5, qFe9/qHg9.2/qAs9.2 on chromosome 9, and qCd10/qHg10 on chromosome 10. Importantly, qSe1/qCd1, can significantly improve the Se content while reduce the Cd content, and qFe5.2/qZn5.2 can significantly improve both the Fe and Zn contents, they were delimited to an interval about 53.8 Kb and 26.2 Kb, respectively. These QTLs detected from Oryza longistaminata not only establish the basis for subsequent gene cloning to decipher the genetic mechanism of mineral element accumulation, but also provide new genetic resource for rice quality improvement.

THU0596 ABNORMAL RIGHT VENTRICLE RESERVE ON EXERCISE PREDICTS PULMONARY HYPERTENSION IN MIXED CONNECTIVE TISSUE DISEASE: A CASE REPORT

Background:

Pulmonary hypertension is one of the most common complications in patients with mixed connective tissue disease (MCTD). Patients are usually at the late stage and have irreversible right heart dysfunction when diagnosed as pulmonary hypertension with the rest echocardiography. Early detection of right heart dysfunction before pulmonary hypertension is essential to ensure that patients receive timely and appropriate treatment for this progressive disease. We aimed to use exercise stress echocardiography to detect early right heart dysfunction in patients with CTD and without pulmonary hypertension.

Objectives:

To present a clinical case of MCTD with normal right ventricular (RV) function at resting but presenting RV dysfunction on exercise, who developed pulmonary hypertension after one-year follow-up.

Methods:

Case report. The patient was subject to the treadmill exercise stress echocardiography. The autoantibodies including anti-nRNP/Sm, anti-Ro-52, and antinuclear antibody (ANA) were detected. The patient was followed-up to one year.

Results:

A 31-year-old female patient was admitted to our department in 2018, with a history of MCTD for five years. Autoantibodies testing revealed that the patient was positive for anti-nRNP/Sm (+++), anti-Ro-52 (+++), and ANA (1:3200). Echocardiography revealed no obvious cardiac dysfunction. However, the velocity of tricuspid valve regurgitation was 3.0m/s following treadmill exercise stress. The patient was followed-up to one year. Then, she developed occult pulmonary hypertension with the velocity of tricuspid valve regurgitation of 3.3m/s following treadmill exercise stress. Accordingly, MTX and prednisone were switched to MTX, prednisone, hydroxychloroquine (HCQ) and beraprost.

Conclusion:

This study showed that treadmill exercise echocardiography could detect right heart dysfunction early before diagnosed as pulmonary hypertension with rest echocardiography in patients with MCTD in its early stage.

References:

[1]Aithala R, Alex AG, Danda D. Pulmonary hypertension in connective tissue diseases: an update. Int J Rheum Dis. 2017;20(1):5–24.

Disclosure of Interests:

None declared

Deciphering the Genetic Basis of Lodging Resistance in Wild Rice Oryza longistaminata

The abuse of fertilizer results in tall rice plants that are susceptible to lodging and reduced plant yield. Hence, it is important to identify and utilize the quantitative trait loci (QTLs)/genes for lodging resistance breeding. Oryza longistaminata exhibits a strong stem and high biomass productivity, which could be a candidate gene pool for cultivars lodging resistance improvement. Here, a set of 152 BC2F20 lines derived from a cross between a cultivated line 93-11 and O. longistaminata was evaluated for lodging resistance. QTL mapping analysis combined with single-nucleotide polymorphism (SNP) marker derived from high-throughput sequencing identified 12 QTLs for stem diameter (SD), 11 QTLs for stem length (SL), and 3 QTLs for breaking strength (BS). Of which, 14 QTLs were first identified from O. longistaminata. A major QTL, qLR1, which was delimited to a region ∼80 kb on chromosome 1, increased stem diameter, stem length, and breaking strength. Another major QTL, qLR8, that was delimited in an interval ∼120 kb on chromosome 8, significantly enhanced the breaking strength. These results provide evidence that O. longistaminata can be exploited to develop lodging-resistant rice lines.

Estrogen-related receptor participates in regulating glycolysis and influences embryonic development in silkworm Bombyx mori

Estrogen-related receptors (ERRs) play indispensable roles in development, energy metabolism, and cancers and are metabolic switches in Drosophila. However, the mechanism underlying their metabolic role is unknown in insects. This study analysed the expression profiles of Bombyx mori ERR (BmERR), hexokinase (BmHK), pyruvate kinase (BmPK) and phosphofructokinase (BmPFK) during embryonic development. The expression of BmERR tended to be similar to that of the other genes. We observed a regulatory association between BmERR and glycolytic rate-limiting enzymes by BmERR overexpression, RNA interference (RNAi), and ERR inhibitors in B. mori embryo cells. Subsequently, ERR cis-regulation elements (ERREs) were predicted and identified in the BmPFK promoter. Transfection assays, electrophoretic mobility shift assays and chromatin immunoprecipitation showed that BmERR can bind to one of these elements to regulate the expression of BmPFK. ERREs were also predicted in the BmHK and BmPK promoters. In the eggs, the expression of glycolytic rate-limiting enzyme genes was suppressed when the expression of BmERR was interference by double-stranded BmERR, the glucose levels also was increased. Meanwhile, the development of silkworm embryos was delayed by about 1 day. These results indicate that BmERR can bind to the ERREs of glycolytic gene promoters and regulate the expression of glycolytic genes, ultimately affecting embryonic development in silkworms.

Analysis of Characteristics and Relevant Factors of 1 340 Cases of Intentional Injury Cases in Southwest China

Abstract

Objective To investigate the characteristics and patterns of factors such as victims' information, injury tools and time of occurrence of intentional injury cases in southwest China. Methods One thousand three hundred and forty intentional injury cases from several places in southwest China from 2014 to 2016 assessed as minor injury level Ⅱ and above had been randomly selected. Data on victims' information, motives, injury tools, sites of occurrence, time of occurrence, injured parts and degrees of injury were classified and gathered, and then association analyses of motives and types of injury tools as well as degrees of injury and injury tools were made. Results Most of the victims were young adults between 20-50 years （65.2%）, male （82.3%）, rural household registration （62.8%）; the motives were mainly dispute （45.8%）. Injury tools were mostly blunt （54.6%） or sharp （36.0%）. Specifically, injuries were mostly made bare-handed （36.9%） and by cutting tools （33.2%）; the cases mainly occurred in public areas （59.0%）. Cases occurred more frequently in January （11.3%）, February （13.1%）, March （11.6%） and from 22：00 to 01：00 every night. Injuries mainly involved the craniofacial region. The wounds were mainly assessed as minor injury level Ⅱ （61.6%）. There was statistical significance in the difference of types of injury tools among cases with different motives （P<0.05）. There was statistical significance in the difference of the distribution of injury tools among cases with different degrees of injury （P<0.05）. Conclusion The occurrence of intentional injury cases in southwest China has potential patterns and relevant influencing factors. Prevention and analysis of such cases need to be comprehensively considered from the aspects such as victims' information, injury tools and time of occurrence.

Quantitative Trait Locus Mapping of the Combining Ability for Yield-Related Traits in Wild Rice Oryza longistaminata

In decades of hybrid rice breeding, the combining ability has been successfully used to evaluate excellent parental lines and predict heterosis. However, previous studies for the combining ability mainly focused on cultivated rice and rarely involved wild rice. In this study, for the first time, we identified 20 new quantitative trait loci (QTLs) for the combining ability in wild rice using a North Carolina II mating design. Among them, qGCA1, one of the major QTLs that can significantly improve the general combining ability of the plant height, spikelet number, and yield per plant, was delimited to an interval of about 72 kb on chromosome 1. qSCA8, another major QTL, which can significantly improve the specific combining ability of the seed-setting rate and yield per plant, was located in an interval of about 90 kb on chromosome 8. These QTLs discovered from wild rice will provide new ideas to explain the genetic mechanism of the combining ability and establish the basis for breeding of high-combining-ability rice.

QTL Mapping of Seed Vigor of Backcross Inbred Lines Derived From Oryza longistaminata Under Artificial Aging

Seed vigor is an important character of seed quality that promotes rice to germinate rapidly from soil and developing to a strong seedling, especially in the current rice direct-sowing production system. However, previous studies for seed vigor mainly concentrate in cultivars, and less reports involving in wild rice. In this study, 152 backcross inbred lines (BILs) derived from wild rice Oryza longistaminata were genotyped with re-sequencing technology, and QTLs for seed vigor related traits under normal and artificial aging treatment were analyzed. Totally, 36 QTLs were detected, of which, eight for germination potential (GP), 10 for germination rate (GR), 9 for seedling length (SL), and 9 for root length (RL). Among these, 14 novel QTLs were identified from O. longistaminata. Of which, six QTLs were related to germination, and eight related to seedling growth under aging stress. What's more, the major QTLs q9SL1.1, q6SL1.1, and q3SL1.1 for seedling length were fallen in the same locus and fine-mapped an interval about 90 Kb. The major QTLs q9GR8.1 and q9GP8.1 related with germination were fine-mapped to an interval about 90 Kb. This work will provide us basis for breeding of high seed vigor rice in rice breeding programs and further cloning of these genes.

Association of maternal KIR and fetal HLA-C genes with the risk of preeclampsia in the Chinese Han population

INTRODUCTION

This study is to investigate the distribution of inhibitory and activating killer-cell immunoglobulin-like receptors (KIRs) and the combination of KIR/human leukocyte antigen (HLA)-C in women with preeclampsia in the Chinese Han population.

METHODS

A total of 271 patients and 295 controls were enrolled in our study. The inhibitory/activating KIR and HLA-C genes were detected using the PCR-SSP (polymerase chain reaction with sequence-specific primers) method.

RESULTS

Our result showed that decreased numbers of individual activating KIR genes (2DS2, 2DS3, and 2DS5) were observed in women with preeclampsia. Furthermore, the gene frequency of total activating KIRs was significantly lower in patients compared with that of the controls (P = 0.03). The frequency of the KIR2DL1 gene was increased in women with preeclampsia when a homozygous HLA-C2 allele appeared in the fetus.

CONCLUSION

The results suggest that a KIR genetic variation might influence the risk of preeclampsia. The lack of activating KIRs could possibly lower uterine natural killer (uNK) cell activation, thereby contributing to the pathogenesis of preeclampsia. Moreover, the imbalance of the inhibitory or activating signals at the maternal-fetal interface seems to play a regulatory role in the occurrence of preeclampsia.

Thorium(IV) removal from aqueous medium by citric acid treated mangrove endophytic fungus Fusarium sp. #ZZF51

Thorium(IV) biosorption is investigated by citric acid treated mangrove endophytic fungus Fussarium sp. #ZZF51 (CA-ZZF51) from South China Sea. The biosorption process was optimized at pH 4.5, equilibrium time 90 min, initial thorium(IV) concentration 50 mg L(-1) and adsorbent dose 0.6 g L(-1) with 90.87% of removal efficiency and 75.47 mg g(-1) of adsorption capacity, which is obviously greater than that (11.35 mg g(-1)) of the untreated fungus Fussarium sp. #ZZF51 for thorium(IV) biosorption under the condition of optimization. The experimental data are analyzed by using isotherm and kinetic models. Kinetic data follow the pseudo-second-order model and equilibrium data agree very well with the Langmuir model. In addition, FTIR analysis indicates that hydroxyl, amino, and carbonyl groups act as the important roles in the adsorption process.

Determining the microbiological criteria for lot rejection from the performance objective or food safety objective

The Microbiological Criteria (MC) is a set of parameters used to determine whether a specific lot of food is acceptable or not. These parameters are the microbial test protocol and its sensitivity, the confidence level that an unacceptable lot will be detected, the number of samples to be taken and the number of positive samples that are allowed before rejecting the lot. Determining the microbiological criteria begins with knowledge of the distribution of contamination from samples within a lot, particularly within a lot that is just at the unacceptable level of the microbial hazard. The just unacceptable lot can be defined by the Food Safety Objective (FSO) or Performance Objectives (PO), the small fraction of samples that can exceed these values and the standard deviation of the samples from the lot. With this information, a microbial test protocol is chosen to have a sensitivity level that would detect between approximately 15% and 45% of the samples. A confidence level for the MC and the number of positive samples that would be acceptable (c value which is usually zero) are also chosen. With this information the number of samples (n) required can be calculated. A critical factor in setting the microbiological criteria is the sensitivity of the microbiological test (m value). The sample size (weight) and sampling procedure can affect the standard deviation of the samples, particularly foods with non-homogeneous distribution and low numbers of microorganisms. Sampling, sample preparation and analytical procedures that reduce the variation between the samples will affect the choice of m value and maximum lot mean that meets the MC.

Coherent combination of high-power, zigzag slab lasers

We demonstrate a scalable architecture for a high-power, high-brightness, solid-state laser based on coherent combinations of master oscillator power amplifier chains. A common master oscillator injects a sequence of multikilowatt Nd:YAG zigzag slab amplifiers. Adaptive optics correct the wavefront of each amplified beamlet. The beamlets are tiled side by side and actively phase locked to form a single output beam. The laser produces 19 kW with beam quality <2x diffraction limited. To the best of our knowledge, this is the brightest cw solid-state laser demonstrated to date.

Computer-assisted guidewire insertion for hip fracture fixation

OBJECTIVE

: This study was designed to test in a laboratory setting a novel computer-assisted fluoroscopic technique and a conventional fluoroscopic technique for open reduction and internal fixation (ORIF) of hip fractures. Our hypothesis is that a novel computer-assisted fluoroscopic technique will achieve acceptable guidewire placement in one pass, with decreased fluoroscopic time and with accuracy and precision better than conventional technique.

DESIGN

Prospective, randomized trials.

SETTING

Laboratory.

PARTICIPANTS

Thirty, Sawbone, femur phantoms.

INTERVENTION

Dynamic hip screw guidewires were inserted into 15 femur phantoms under fluoroscopic guidance by using computer-assisted fluoroscopic ORIF technique, and 15 femurs were inserted by using a conventional fluoroscopic-assisted ORIF technique.

MAIN OUTCOME MEASUREMENTS

Ideal guidewire placement was defined as the center of the femoral head, 5 mm from the apical bone edge on anteroposterior and lateral views. Accuracy was measured as distance to ideal placement, and the number of passes and fluoroscopic time were noted for each trial.

RESULTS

The computer-assisted technique achieved an average guidewire placement that was as accurate as the conventional technique in fewer passes, 1.1 +/- 0.2 (mean +/- standard deviation) compared with 2.4 +/- 1.1 (P < 0.0001), respectively, and with fewer fluoroscopic images, 2 +/- 0 compared with 13.5 +/- 3 (P < 0.0002), respectively. Guidewire placement in both groups was within the tip-apex distance defined by Baumgaertner et al.

CONCLUSIONS

The computer-assisted technique was significantly more accurate and precise than conventional technique. It also required fewer drill tracks through the femur and exposed the patient and the surgical team to significantly less ionizing radiation.

Matched-pair analysis of all-polyethylene versus metal-backed tibial components

Forty-eight matched pairs of osteoarthritic knees from patients who underwent primary total knee arthroplasty with a round-on-round, Apollo Knee System were studied to evaluate the outcome between all-polyethylene and metal-backed tibial components. Patients were matched for patient factors, preoperative deformities, cruciate salvage or sacrifice, and surgical technique. At the last follow-up (average, 38.4 months), there was no statistically significant difference in terms of knee scores, patient self-assessment, and radiographic outcomes. No component required revision, and no revisions were pending. Maintenance of these results over time would project into better long-term success for all-polyethylene tibial components because of the amount of wear and osteolysis with current modular metal-backed tibial components. We advocate the use of a more cost-effective all-polyethylene tibial component in elderly patients (>70 years old) who are not likely to need the versatility of exchange of a modular polyethylene insert because of wear.

[Study on the determination of photophysical parameters of the non-protected fluid room temperature phosphorescence by lifetime method]

The heavy atom pertuber (HAP) can promote the intersystem crossing and the rates of radiative and nonradiative processes of triplet state, thus shortens the phosphorescence lifetime. The determination of kinetic parameters for luminescence process is very importance to understand luminescence process and the mechanisms of the heavy atom effects. In this paper, 1-chloronaphthalene and 1-bromonaphthalene were selected as the modal compounds, the possibility of determination of photophysical parameters for emission of nonprotected fluid room temperature phosphorescence (NP-RTP) by RTP lifetime method was studied based on the definition on the phosphorescence lifetime and relation with the concentration of HAP. The results obtained by two ways prove that the RTP lifetime method can be used to determine photophysical parameters for RTP emission.

[Clinical and MRI diagnosis of nasopharyngeal carcinoma with orbital spread]

OBJECTIVE

To study the routes, clinical manifestations and MRI characteristics of nasopharyngeal carcinoma (NPC) with orbital spread.

METHODS

Twenty (23 eyes) such cases were selected, including 6 (7 eyes) preradiotherapy cases and 14 (16 eyes) postradiotherapy cases. The magnetic resonance imaging (MRI) axial, coronal, sagittal routine procedures and gadolinium-diethylene triamine pentaacetic acid (GD-DTPA) contrast-enhanced scan were performed. Fatty-restraint scan was performed after enhancement only on 3 cases. The diagnosis in all the patients was proved by the biopsy from the nasopharynx.

RESULTS

(1) Single orbit involvement was seen in 17 patients, 12 in the left and 5 in the right orbit. Bilateral orbit involvement was only found in 3 patients. (2) Major clinical manifestations of orbital involvement by NPC included: 13 cases (15 eyes) suffered from decrease of visual acuity, 9 cases (10 eyes) with exophthalmos, 11 patients (12 eyes) with ocular movement disorder, 7 cases (9 eyes) with diplopia and 5 cases (7 eyes) with blepharoptosis. (3) MRI appearances: There were 13 cases (15 eyes) with optic nerve involvement, 9 patients (11 eyes) with abnormalities in extraocular muscle, 8 cases (9 eyes) with retrobulbar tumor and 15 cases (17eyes) with orbital apex and orbital lamina bony involvement. (4) The three main routes for orbital involvement in NPC patients were as follows: (a) through cavernous sinus (the skull base) to superior orbital fissure. (b) through paranasal sinus (particularly the ethmoid sinus). (c) through pterygopalatine fossa to inferior orbital fissure.

CONCLUSION

MR imaging is very useful to demonstrate the presence, location and extent of orbital involvement in NPC patients.

Branched chain amino acids activate messenger ribonucleic acid translation regulatory proteins in human skeletal muscle, and glucocorticoids blunt this action

Branched chain amino acids (BCAA) are particularly effective anabolic agents. Recent in vitro studies suggest that amino acids, particularly leucine, activate a signaling pathway that enhances messenger ribonucleic acid translation and protein synthesis. The physiological relevance of these findings to normal human physiology is uncertain. We examined the effects of BCAA on the phosphorylation of eukaryotic initiation factor 4E-binding protein 1 (eIF4E-BP1) and ribosomal protein S6 kinase (p70(S6K)) in skeletal muscle of seven healthy volunteers. We simultaneously examined whether BCAA affect urinary nitrogen excretion and forearm skeletal muscle protein turnover and whether the catabolic action of glucocorticoids could be mediated in part by inhibition of the action of BCAA on the protein synthetic apparatus. BCAA infusion decreased urinary nitrogen excretion (P < 0.02), whole body phenylalanine flux (P < 0.02), plasma phenylalanine concentration (P < 0.001), and improved forearm phenylalanine balance (P = 0.03). BCAA also increased the phosphorylation of both eIF4E-BP1 (P < 0.02) and p70(S6K) (P < 0.03), consistent with an action to activate the protein synthetic apparatus. Dexamethasone increased plasma phenylalanine concentration (P < 0.001), prevented the BCAA-induced anabolic shift in forearm protein balance, and inhibited their action on the phosphorylation of p70(S6K). We conclude that in human skeletal muscle BCAA act directly as nutrient signals to activate messenger ribonucleic acid translation and potentiate protein synthesis. Glucocorticoids interfere with this action, and that may be part of the mechanism by which they promote net protein catabolism in muscle.

Dexamethasone inhibits the stimulation of muscle protein synthesis and PHAS-I and p70 S6-kinase phosphorylation

Glucocorticoids inhibit protein synthesis in muscle. In contrast, insulin and amino acids exert anabolic actions that arise in part from their ability to phosphorylate ribosomal p70 S6-kinase (p70(S6k)) and eukaryotic initiation factor (eIF)4E binding protein (BP)1 (PHAS-I), proteins that regulate translation initiation. Whether glucocorticoids interfere with this action was examined by giving rats either dexamethasone (DEX, 300 microg. kg(-1). day(-1), n = 10) or saline (n = 10) for 5 days. We then measured the phosphorylation of PHAS-I and p70(S6k) in rectus muscle biopsies taken before and at the end of a 180-min infusion of either insulin (10 mU. min(-1). kg(-1) euglycemic insulin clamp, n = 5 for both DEX- and saline-treated groups) or a balanced amino acid mixture (n = 5 for each group also). Protein synthesis was also measured during the infusion period. The results were that DEX-treated rats had higher fasting insulin, slower glucose disposal, less lean body mass, and decreased protein synthetic rates during insulin or amino acid infusion (P < 0.05 each). DEX did not affect basal PHAS-I or p70(S6k) phosphorylation but blocked insulin-stimulated phosphorylation of PHAS-I- and amino acid-stimulated phosphorylation of both PHAS-I and p70(S6k) (P < 0.01, for each). DEX also increased muscle PHAS-I concentration. These effects can, in part, explain glucocorticoid-induced muscle wasting.

[Local recurrence of nasopharyngeal carcinoma with normal mucous membrane after radiation therapy: MR imaging findings]

OBJECTIVE

The purpose of this work was to investigate and analyze the MR imaging features of postradiation local recurrence of nasopharyngeal carcinoma (NPC) with normal mucous membrane.

METHODS

24 such cases were studied. The diagnosis of NPC recurrence was pathologically confirmed in 15 patients, and was corroborated by repeated radiation therapy and serial follow-ups in 9 patients. MR imaging routine procedures and Gd-DTPA enhancement were performed for all patients.

RESULTS

The MR imaging findings were as follows: 1. The recurrent tumor mass was located in the prestyloid space in 8 patients, with skull base erosion and intracranial infiltration in 7 patients; 2. Retrostyloid space recurrence in 2 patients; 3. Direct bony erosion of the skull base in 7 patients; 4. Recurrence in nasal cavity and ethmoid sinuses in 3 patients; 5. Submucous cystic recurrence in 2 patients; 6. Mixed patterns of recurrence in 2 patients. Except 2 cases of cystic tumor recurrence, all cases exhibited slight hypo- or iso-intensity on T1-weighted images, slight hyper-intensity on T2-weighted images, and moderate to marked enhancement after Gd-DTPA administration.

CONCLUSION

There are several special patterns of local NPC tumor recurrence after radiation therapy in the presence of normal nasopharyngeal mucosa. MR imaging is the method of choice to depict the location and extent of NPC tumor recurrence.

Study of properties on non-protected room temperature phosphorescence and delayed excimer fluorescence of pyrene solution

A strong and stable room temperature phosphorescence (RTP) and delayed excimer fluorescence signal located at 596 and 475 nm, respectively, can be induced for pyrene solution in the absence of any protective medium only use KI or TlNO3 as a heavy atom perturber (HAP) and Na2SO3 as a deoxygenator. Both lifetimes of RTP and the delayed fluorescence are in the order of X-ms and the intensities are changed with kind and amount of HAP, but the peak positions are same and there is a iso-luminescent point in the emission spectra corresponding to emission at 475 nm and at 596 nm. The optimum conditions and the effects of kind and amount of HAP and organic solvents on luminescence properties of pyrene solution were studies in detail, and the photophysical process in the presence of KI or TlNO3 for phosphorescence and delayed excimer fluorescence emission of pyrene solution was discussed.

Molecular identification using flow cytometry histograms and information theory

Flow cytometry is a common technique for quantitatively measuring the expression of individual molecules on cells. The molecular expression is represented by a frequency histogram of fluorescence intensity. For flow cytometry to be used as a knowledge discovery tool to identify unknown molecules, histogram comparison is a major limitation. Many traditional comparison methods do not provide adequate assessment of histogram similarity and molecular relatedness. We have explored a new approach applying information theory to histogram comparison, and tested it with histograms from 14 antibodies over 3 cell types. The information theory approach was able to improve over traditional methods by recognizing various non-random correlations between histograms in addition to similarity and providing a quantitative assessment of similarity beyond hypothesis testing of identity.

Physiological hyperinsulinemia stimulates p70(S6k) phosphorylation in human skeletal muscle

Using tracer methods, insulin stimulates muscle protein synthesis in vitro, an effect not seen in vivo with physiological insulin concentrations in adult animals or humans. To examine the action of physiological hyperinsulinemia on protein synthesis using a tracer-independent method in vivo and identify possible explanations for this discrepancy, we measured the phosphorylation of ribosomal protein S6 kinase (P70(S6k)) and eIF4E-binding protein (eIF4E-BP1), two key proteins that regulate messenger ribonucleic acid translation and protein synthesis. Postabsorptive healthy adults received either a 2-h insulin infusion (1 mU/min.kg; euglycemic insulin clamp; n = 6) or a 2-h saline infusion (n = 5). Vastus lateralis muscle was biopsied at baseline and at the end of the infusion period. Phosphorylation of P70(S6k) and eIF4E-BP1 was quantified on Western blots after SDS-PAGE. Physiological increments in plasma insulin (42 +/- 13 to 366 +/- 36 pmol/L; P: = 0.0002) significantly increased p70(S6k) (P: < 0.01), but did not affect eIF4E-BP1 phosphorylation in muscle. Plasma insulin declined slightly during saline infusion (P: = 0.04), and there was no change in the phosphorylation of either p70(S6k) or eIF4E-BP1. These findings indicate an important role of physiological hyperinsulinemia in the regulation of p70(S6k) in human muscle. This finding is consistent with a potential role for insulin in regulating the synthesis of that subset of proteins involved in ribosomal function. The failure to enhance the phosphorylation of eIF4E-BP1 may in part explain the lack of a stimulatory effect of physiological hyperinsulinemia on bulk protein synthesis in skeletal muscle in vivo.

Cerebral artery K(ATP)- and K(Ca)-channel activity and contractility: changes with development

The present study was designed to test the hypothesis that in cerebral arteries of the fetus, ATP-sensitive (K(ATP)) and Ca(2+)-activated K(+) channels (K(Ca)) play an important role in the regulation of intracellular Ca(2+) concentration ([Ca(2+)](i)) and that this differs significantly from that of the adult. In main branch middle cerebral arteries (MCA) from near-term fetal ( approximately 140 days) and nonpregnant adult sheep, simultaneously we measured norepinephrine (NE)-induced responses of vascular tension and [Ca(2+)](i) in the absence and presence of selective K(+)-channel openers/blockers. In fetal MCA, in a dose-dependent manner, both the K(ATP)-channel opener pinacidil and the K(Ca)-channel opener NS 1619 significantly inhibited NE-induced tension [negative logarithm of the half-maximal inhibitory concentration (pIC(50)) = 5.0 +/- 0.1 and 8.2 +/- 0.1, respectively], with a modest decrease of [Ca(2+)](i). In the adult MCA, in contrast, both pinacidil and NS 1619 produced a significant tension decrease (pIC(50) = 5.1 +/- 0.1 and 7.6 +/- 0.1, respectively) with no change in [Ca(2+)](i). In addition, the K(Ca)-channel blocker iberiotoxin (10(-7) to 10(-6) M) resulted in increased tension and [Ca(2+)](i) in both adult and fetal MCA, although the K(ATP)-channel blocker glibenclamide (10(-7) to 3 x 10(-5) M) failed to do so. Of interest, administration of 10(-7) M iberiotoxin totally eliminated vascular contraction and increase in [Ca(2+)](i) seen in response to 10(-5) M ryanodine. In precontracted fetal cerebral arteries, activation of the K(ATP) and K(Ca) channels significantly decreased both tension and [Ca(2+)](i), suggesting that both K(+) channels play an important role in regulating L-type channel Ca(2+) flux and therefore vascular tone in these vessels. In the adult, K(ATP) and the K(Ca) channels also appear to play an important role in this regard; however, in the adult vessel, activation of these channels with resultant vasorelaxation can occur with no significant change in [Ca(2+)](i). These channels show differing responses to inhibition, e.g., K(Ca)-channel inhibition, resulting in increased tension and [Ca(2+)](i), whereas K(ATP)-channel inhibition showed no such effect. In addition, the K(Ca) channel appears to be coupled to the sarcoplasmic reticulum ryanodine receptor. Thus differences in plasma membrane K(+)-channel activity may account, in part, for the differences in the regulation of contractility of fetal and adult cerebral arteries.

Dual role of PKC in modulating pharmacomechanical coupling in fetal and adult cerebral arteries

This study tested the hypothesis that protein kinase C (PKC) has dual regulation on norepinephrine (NE)-mediated inositol 1,4, 5-trisphosphate [Ins (1,4,5)P(3)] pathway and vasoconstriction in cerebral arteries from near-term fetal ( approximately 140 gestational days) and adult sheep. Basal PKC activity values (%membrane bound) in fetal and adult cerebral arteries were 38 +/- 4% and 32 +/- 4%, respectively. In vessels of both age groups, the PKC isoforms alpha, beta(I), beta(II), and delta were relatively abundant. In contrast, compared with the adult, cerebral arteries of the fetus had low levels of PKC-epsilon. In response to 10(-4) M phorbol 12,13-dibutyrate (PDBu; PKC agonist), PKC activity in both fetal and adult cerebral arteries increased 40-50%. After NE stimulation, PKC activation with PDBu exerted negative feedback on Ins(1,4,5)P(3) and intracellular Ca(2+) concentration ([Ca(2+)](i)) in arteries of both age groups. In turn, PKC inhibition with staurosporine resulted in augmented NE-induced Ins(1,4,5)P(3) and [Ca(2+)](i) responses in adult, but not fetal, cerebral arteries. In adult tissues, PKC stimulation by PDBu increased vascular tone, but not [Ca(2+)](i). In contrast, in the fetal artery, PKC stimulation was associated with an increase in both tone and [Ca(2+)](i). In the presence of zero extracellular [Ca(2+)], these PDBu-induced responses were absent in the fetal vessel, whereas they remained unchanged in the adult. We conclude that, although basal PKC activity was similar in fetal and adult cerebral arteries, PKC's role in NE-mediated pharmacomechanical coupling differed significantly in the two age groups. In both fetal and adult cerebral arteries, PKC modulation of NE-induced signal transduction responses would appear to play a significant role in the regulation of vascular tone. The mechanisms differ in the two age groups, however, and this probably relates, in part, to the relative lack of PKC-epsilon in fetal vessels.

Duplication of chromosome region 4q28.3-qter in monozygotic twins with discordant phenotypes

We describe monozygotic twins with partially discordant phenotypes who were found to have a duplication of chromosome region 4q28.3-qter. The duplicated region of chromosome 4 resulted from an unbalanced segregation of a balanced maternal (4;22)(q28.3;p13) translocation. Duplication of the long arm of chromosome 4 has been described in >60 patients; however, it usually results from the unbalanced segregation of a parental balanced translocation and has an associated monosomy. Twenty cases of dup 4q without an associated monosomy have been reported, and this is the only case of dup 4q28. 3-qter. All cases of dup 4q are reviewed, and phenotypic aspects are analyzed. Issues of monozygotic twinning and other birth defects also are addressed.

Cerebral artery sarcoplasmic reticulum Ca(2+) stores and contractility: changes with development

To test the hypothesis that sarcoplasmic reticulum (SR) Ca(2+) stores play a key role in norepinephrine (NE)-induced contraction of fetal and adult cerebral arteries and that Ca(2+) stores change with development, we performed the following study. In main branch middle cerebral arteries (MCA) from near-term fetal ( approximately 140 days) and nonpregnant adult sheep, we measured NE-induced contraction and intracellular Ca(2+) concentration ([Ca(2+)](i)) in the absence and presence of different blockers. In adult MCA, after thapsigargin (10(-6) M), the NE-induced responses of tension and [Ca(2+)](i) were 37 +/- 5 and 47 +/- 7%, respectively, of control values (P < 0.01 for each). In the fetal artery, in contrast, this treatment resulted in no significant changes from control. When this was repeated in the absence of extracellular Ca(2+), adult MCA increases in tension and [Ca(2+)](i) were 32 +/- 5 and 13 +/- 3%, respectively, of control. Fetal cerebral arteries, however, showed essentially no response. Ryanodine (RYN, 3 x 10(-6) to 10(-5) M) resulted in increases in tension and [Ca(2+)](i) in both fetal and adult MCA similar to that seen with NE. For both adult and fetal MCA, the increased tension and [Ca(2+)](i) responses to RYN were essentially eliminated in the presence of zero extracellular Ca(2+). These findings provide evidence that in fetal MCA, in contrast to those in the adult, SR Ca(2+) stores are of less importance in NE-induced contraction, with such contraction being almost wholly dependent on Ca(2+) flux via plasma membrane L-type Ca(2+) channels. In addition, they suggest that in both adult and fetal MCA, the RYN receptor is coupled to the plasma membrane Ca(2+)-activated K(+) channel and/or L-type Ca(2+) channel.

Amino acids regulate skeletal muscle PHAS-I and p70 S6-kinase phosphorylation independently of insulin

Refeeding reverses the muscle protein loss seen with fasting. The physiological regulators and cellular control sites responsible for this reversal are incompletely defined. Phosphorylation of phosphorylated heat-acid stabled protein (PHAS-I) frees eukaryotic initiation factor 4E (eIF4E) and stimulates protein synthesis by accelerating translation initiation. Phosphorylation of p70 S6-kinase (p70(S6k)) is thought to be involved in the regulation of the synthesis of some ribosomsal proteins and other selected proteins with polypyrimidine clusters near the transcription start site. We examined whether phosphorylation of PHAS-I and p70(S6k) was increased by feeding and determined the separate effects of insulin and amino acids on PHAS-I and p70(S6k) phosphorylation in rat skeletal muscle in vivo. Muscle was obtained from rats fed ad libitum or fasted overnight (n = 5 each). Other fasted rats were infused with insulin (3 microU x min(-1) x kg(-1), euglycemic clamp), amino acids, or the two combined. Gastrocnemius was freeze-clamped, and PHAS-I and p70(S6k) phosphorylation was measured by quantifying the several phosphorylated forms of these proteins seen on Western blots. We observed that feeding increased phosphorylation of both PHAS-I and p70(S6k) (P < 0.05). Infusion of amino acids alone reproduced the effect of feeding. Physiological hyperinsulinemia increased p70(S6K) (P < 0.05) but not PHAS-I phosphorylation (P = 0.98). Addition of insulin to amino acid infusion was no more effective than amino acids alone in promoting PHAS-I and p70(S6k) phosphorylation. We conclude that amino acid infusion alone enhances the activation of the protein synthetic pathways in vivo in rat skeletal muscle. This effect is not dependent on increases in plasma insulin and simulates the activation of protein synthesis that accompanies normal feeding.

Microbial risk assessment: dose-response relations and risk characterization

Characterizations of the risks associated with foodborne pathogens are dependent on the availability of information on the population's exposure to the biological agents. However, by itself, exposure data are insufficient to assess the public health impact of pathogenic microorganisms. This requires the availability of effective dose-response models. Successful development of models that describe dose-response relations for enteric pathogens is dependent on a sound understanding of the mechanisms of pathogenicity associated with individual pathogens. This includes knowledge of how the various pathogen, host, and food matrix factors influence pathogenicity. Currently, a group of sigmoidal mathematical equations are used to empirically describe dose-response relations. While these have proven to be highly useful, advances in microbial food safety risk assessment will likely require the development of mechanistic models that more effectively consider the range of factors that influence the frequency and severity of foodborne infections in a population.

[Study on the anti-müllerian hormone served as a marker for granulosa cell tumor of ovary]

OBJECTIVE

To probe the experimental basis for anti-mullerian hormone(AMH) served as a specific tumor label in diagnosis of granulosa cell tumor(GCT) of ovary.

METHODS

The expression of AMH and its receptor mRNA in early and late GCT of ovary in transgenic mice was studied by using immunohistochemistry, in stiu hybridization and Northern hybridization. Furthermore, the expression of AMH and its receptor mRNA in cultured GCT cells was also determined by using radioiodine labeling method and Northern hybridization.

RESULTS

In the early ovary GCT of transgenic mice, immunohistochemistry showed that AMH was positively stained as brownish yellow granulars, which were located in the cell membrane of the tumor, in situ hybridization showed its receptor mRNA was positive as blue granulars, which were also located in the cell membrane. The positive rate of both AMH and its receptor mRNA was 100%. Results by northern hybridization also showed that the positive rate of AMH and its receptor mRNA in the early ovary GCT and GCT cells was 100%. Radioautography indicated that there was a radioactive bright point, the binding rate of 125I labeled AMH with tumor cells reached 100%.

CONCLUSIONS

AMH can be served as a specific tumor marker in the diagnosis of difficult and complicated tumors of ovary, and in the diagnosis, treatment and follow-up survey of the early GCT.

[Research progress on PGPR/AMF interactions]

As one of the rhizospheric microorganisms PGPR(Plant Growth Promoting Rhizobacteria) and AMF(Arbuscular Mycorrhizal Fungi) play an important role in promoting plant growth. It is of significance to further study and elucidate the interactions between them to utilize and regulate the interactions among rhizospheric microorganisms, and promote and protecte plant growth. Many research results show that on one hand, there exists synergism between PGPR and AMF. AMF can transfer PGPR or act as a media in the process of spread of PGPR along roots, where PGPR create many beneficial conditions for the infection of AMF. Both of them can indirectly enhance the other side's colonization or infection ability through their own promoting role on plant growth. On the other hand, they compete with each other for nutrients and niches, and probably produce some secondary metabolites which cause detrimental effects on the other. However, whether these interactions are synergistic or competitive depends upon the AM fungal or PGPR species involved. So far, the research work is extensive, even in molecular level in some aspects, but not systematic and deep. It is believed however, with the development of techniques in molecular biology and the increasing application of advanced testing methods, the new breakthroughs will be gained in the study and understanding on the interactions.

[The relationship of brainstem auditory evoked potential to cerebral blood flow volume in with vertebrobasilar transient ischemic vertigo]

This study was aimed at the relationship of brain-stem auditory evoked potential(BAEP) with cerebral blood flow(CBF) volume and vascular pathological changes in patients with vertebro-basilar transient ischemic vertigo (VBTIV). 65 patients were examined by magnetic resonance angiography(MRA), transcranial Dopplar(TCD) and BAEP; 26 controls were examined by MRA and TCD. In the patient group, MRA showed that vascular pathological changes were obvious in 50 patients, and obscure or absent in 15 patients. The CBF volume [112.3-278.9 ml/min (2s)] of control group was higher than that (48.0-262.0 ml/min) of the patients group (t = 2.43, P < 0.01) in which 15 patients had low CBF volume and 50 patients had normal CBF volume. The BAEP of 47(72.3%) patients was abnormal. Out of 15 patients with low CBF volume, 14(93.3%) had abnormal BAEP, but out of 50 patients with normal CBF volume, only 33(66%) patients had abnormal BAED (chi 2 = 4.34, P < 0.05). In the 50 patients with obscure obvious vascular pathological changes, 40(80%) patients had abnormal BAEP, but in the 15 patients with obscure or without the changes, only 7(43.3%) patients had abnormal BAEP (chi 2 = 4.86, P < 0.05). These results suggested that there might be a close relationship of BAEP with CBF volume and vascular pathological changes.

Frequency and prognostic significance of pericardial effusion in primary pulmonary hypertension. PPH Study Group. Primary pulmonary hypertension

Pericardial effusion was noted in 43 of 79 patients (54%) with severe primary pulmonary hypertension. Larger effusion was associated with hemodynamic and echocardiographic evidence of right heart failure, impaired exercise tolerance, and a poor 1-year prognosis.

Role of Ca(2+) channels in NE-induced increase in [Ca(2+)](i) and tension in fetal and adult cerebral arteries

In vascular smooth muscle, elevation of agonist-induced intracellular Ca(2+) concentration ([Ca(2+)](i)) occurs via both Ca(2+) release from intracellular stores and Ca(2+) influx across the plasma membrane. In the cerebral vasculature of the fetus and adult the relative roles of these mechanisms have not been defined. To test the hypothesis that plasma membrane L-type and receptor-operated Ca(2+) channels play a key role in NE-induced vasoconstriction via alterations in plasma membrane Ca(2+) flux and that this may change with developmental age, we performed the following study. In main branch middle cerebral arteries (MCA) from near-term fetal ( approximately 140 days) and nonpregnant adult sheep, we quantified NE-induced responses of vascular tension and [Ca(2+)](i) (by use of fura 2) under standard conditions in response to several Ca(2+) channel blockers and in response to zero extracellular Ca(2+). In fetal and adult MCA, maximal NE-induced tensions (g) were 0.91 +/- 0.12 (n = 10) and 1.61 +/- 0.13 (n = 12), respectively. The pD(2) values for NE-induced tension were both 6.0 +/- 0.1, whereas the fetal and adult maximum responses (%K(max)) were 107 +/- 16 and 119 +/- 7, respectively. The fetal and adult pD(2) values for NE-induced increase of [Ca(2+)](i) were 6.2 +/- 0.1 and 6.4 +/- 0.1, respectively, whereas maximum [Ca(2+)](i) responses were 81 +/- 9 and 103 +/- 15% of K(max), respectively. After 10(-5) M NE-induced contraction, nifedipine resulted in dose-dependent decrease in vessel tone and [Ca(2+)](i) with pIC(50) values for fetal and adult tensions of 7.3 +/- 0.1 and 6.6 +/- 0.1, respectively (P < 0.01; n = 4 each), whereas pIC(50) for [Ca(2+)](i) responses were 7.2 +/- 0.1 and 6.9 +/- 0.1, respectively. The pIC(50) values for tension for diltiazem and verapamil were somewhat lower but showed a similar relationship. The receptor-operated Ca(2+) channel blocker 2-nitro-4 carboxyphenyl-N,N-diphenyl carbamate showed little effect on NE-induced vessel contractility or [Ca(2+)](i). In the absence of extracellular Ca(2+) for 2 min, 10(-5) M NE resulted in markedly attenuated responses of adult MCA tension and [Ca(2+)](i) to 39 +/- 7 and 73 +/- 8% of control values (n = 4). For fetal MCA, exposure to extracellular Ca(2+) concentration resulted in essentially no contractile or [Ca(2+)](i) response (n = 4). Similar blunting of NE-induced tension and [Ca(2+)](i) was seen in response to 10(-3) M lanthanum ion. These findings provide evidence to suggest that especially in fetal, but also in adult, ovine MCA, Ca(2+) flux via L-type calcium channels plays a key role in NE-induced contraction. In contrast, Ca(2+) flux via receptor-operated Ca(2+) channels is of less importance. This developmental difference in the role of cerebrovascular plasma membrane Ca(2+) channels may be an important association with increased Ca(2+) sensitivity of the fetal vessels.

Continuous infusion of epoprostenol improves the net balance between pulmonary endothelin-1 clearance and release in primary pulmonary hypertension

BACKGROUND

Primary pulmonary hypertension results from progressive narrowing of the precapillary pulmonary vasculature. A variety of endothelial abnormalities have been identified, including a net reduction in pulmonary clearance of the vasoconstrictor and smooth muscle mitogen endothelin-1. In many patients, net pulmonary release of endothelin-1 is observed. Chronic infusions of epoprostenol (prostacyclin) improve functional capacity, survival, and hemodynamics in patients with advanced primary pulmonary hypertension. We hypothesized that the epoprostenol infusions, as compared with conventional therapy, might alter the abnormal pulmonary endothelin-1 homeostasis.

METHODS AND RESULTS

Using a subset of patients from a larger randomized study comparing epoprostenol plus conventional therapy (n=11 in the present study) with conventional therapy alone (n=7 in the present study), we determined the ratio of plasma endothelin-1 levels in systemic arterial blood leaving the lung to levels in mixed venous blood entering the lung both before randomization and after 88 days of continuous therapy. There were no differences between the 2 groups before therapy, but by day 88, the epoprostenol-treated group had a greater proportion of patients (82%) with an arterial/venous ratio <1 than did the conventional therapy group, in which only 29% of patients had a ratio <1 (P<0.05).

CONCLUSIONS

These results suggest that continuous epoprostenol therapy may have a beneficial effect on the balance between endothelin-1 clearance and release in many patients with primary pulmonary hypertension and may provide one explanation for the salutary effect of epoprostenol in this disease.

Surrender to win: how adolescent drug and alcohol users change their lives

Adolescent drug and alcohol addiction is a serious problem in the United States. However, some addicted adolescents do quit drinking and using drugs. This paper offers a phenomenological analysis of seven young adults who managed to surrender their addictions and, for anywhere from five to fifteen years, construct sober identities. The participants came from highly dysfunctional homes, began substance use as children, and were polydrug users. A series of catastrophic life events led them to Alcoholics Anonymous, where they were exposed to self-reflective prayer, a cadre of recovering adolescents and, in particular, adults who offered detached nurturing. This provided the support they needed to confront their addictions through the Twelve Steps of Alcoholics Anonymous.