[Epidemic trends and prevention and control of seasonal influenza in China after the COVID-19 pandemic]

During the COVID-19 pandemic, a series of non-pharmaceutical interventions, which were implemented to curb the spread of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), significantly modified the seasonal pattern of influenza. The intensity of influenza activity markedly decreased and B/Yamagata lineage was no longer detected. As the national influenza sentinel surveillance data shown, clear seasonal patterns were observed for influenza between 2012-2019, annually with an average of 14.57% of specimens tested positive for influenza virus. However, the seasonal pattern of influenza was disrupted after the outbreak of COVID-19. In the 2020-2021 season, influenza demonstrated an extremely low activity (yearly positivity rate<1.0%), followed by a resurgence of winter peak in the 2021-2022 season. Following the downgrade of management of COVID-19 to Class B in China in December 26, 2022, social activities gradually resumed, leading to the rebound of influenza activity with an out-of-season ciculation. After COVID-19 pademic, other respiratory infectious diseases caused by SARS-CoV-2, respiratory syncytial virus, and mycoplasma pneumonia were alternatively or concurrently circulated with influenza. The prevention and control of influenza and other respiratory infectious diseases emphasizes a multi-disease prevention strategy, including long-term and continuous monitoring the epidemic trends in influenza virus and SARS-CoV-2, promoting influenza and COVID-19 vaccination among key populations, and strengthening the knowledge and public awareness of prevention and control for respiratory infectious diseases, etc.

Genetic association of COVID-19 severe versus non-severe cases by RNA sequencing in patients hospitalised in Hong Kong

INTRODUCTION

The coronavirus disease 2019 (COVID-19) pandemic has caused extensive disruption of public health worldwide. There were reports of COVID-19 patients having multiple complications. This study investigated COVID-19 from a genetic perspective.

METHODS

We conducted RNA sequencing (RNA-Seq) analysis of respiratory tract samples from 24 patients with COVID-19. Eight patients receiving mechanical ventilation or extracorporeal membrane oxygenation were regarded as severe cases; the remaining 16 patients were regarded as non-severe cases. After quality control, statistical analyses were performed by logistic regression and the Kolmogorov-Smirnov test to identify genes associated with disease severity.

RESULTS

Six genes were associated with COVID-19 severity in both statistical tests, namely RPL15, BACE1-AS, CEPT1, EIF4G1, TMEM91, and TBCK. Among these genes, RPL15 and EIF4G1 played roles in the regulation of mRNA translation. Gene ontology analysis showed that the differentially expressed genes were mainly involved in nervous system diseases.

CONCLUSION

RNA sequencing analysis showed that severe acute respiratory syndrome coronavirus 2 infection is associated with the overexpression of genes involved in nervous system disorders.

[Advances in clinical significance and detection methods research of high density lipoprotein subfractions]

High density lipoprotein (HDL) is an important biochemical index of clinical cardiovascular disease. Many new studies have demonstrated abnormalities of plasma HDL subfractions in patients with this disease,and their clinical significance is greater than the overall abnormalities of HDL. Therefore,the HDL subfraction as an important factor in cardiovascular disease has attracted extensive research and attention. This article summarizes current research on HDL subfractions,their measurements and their relationships with atherosclerosis and coronary artery disease.

[Analysis on the implementation of payment policies for four non-national immunization program vaccines in China]

This study systematically retrieved information on the payment policy of vaccination fees for pneumococcal vaccines, human papillomavirus vaccines, haemophilus influenzae type b vaccines and rotavirus vaccines using a Python-based crawler. The proportion of the population covered by policies among the total applicable population was estimated based on the medical insurance coverage ratio and population data in 2020. This study showed that the payment policies included two categories, government-funded free vaccination policies and medical insurance payment policies. Among the four non-national immunization program vaccines, the free vaccination policies only involved pneumococcal vaccines and human papillomavirus vaccines. Among them, the 13-valent pneumococcal conjugate vaccine, the 23-valent pneumococcal polysaccharide vaccine, and the human papillomavirus vaccine were provided free of charge in 1, 10 and 15 provinces, respectively. For these policies, the corresponding covered population and the proportion among the total applicable population were children aged 6 months to 2 years old (2.5%), older people (1.2% to 21.5%) and middle school girls (1.1% to 12.2%). Medical insurance payment policies were implemented in 14 provinces, and nearly covered the four types of vaccines in the policy implementation areas, with the proportion of the covered population about 10.9% to 41.5% among the total applicable population.

[Adverse cardiovascular effects of antiretrovirals in female mice during gestation]

Objective: To evaluate the effects of antiretrovirals on cardiovascular function and some biochemical indexes in gestational female rats. Methods: Nineteen 9-week-old female and six 10-week-old male SD rats were divided into normal control group (CON) and highly active antiretroviral therapy group (HARRT), 9/10 female rats and 3 male rats were combined into one cage, totally 2 cages. Female rats in CON group were intragastrically given with normal saline (NS, 10 ml/kg) every morning and evening, while female rats in HARRT group were treated with equal volume antiretrovirals (AZT 31.25 mg/kg + 3TC 15.63 mg/kg + LPV/r (41.67/10.42) mg/kg) for 3 months. The body weight and survival rate of female rats were recorded. Echocardiography and multichannel physiological recorder were used to detect arterial blood pressure and cardiac hemodynamic parameters. The levels of blood glucose, blood lipids, myocardial enzymes and liver enzymes were detected by corresponding kits. Myocardial collagen fibers were observed by Masson staining and the ultrastructure of myocardial cells were observed by transmission electron microscopy. Results: All female rats in CON group survived (9/9), while only 6 rats in HARRT group survived (6/10). Compared with CON group, the body weight of female rats in HAART group was decreased significantly(P＜0.01); the levels of left ventricular end diastolic diameter (LVDd), interventricular septal thickness (IVST), thickness of left ventricular posterior wall (LVPWT) , left atrial diameter (LAD) and arterial diastolic pressure were increased significantly (P＜0.05); the level of LVP+dP/dtmax was decreased (P＜0.01). The levels of triglyceride, creatine kinase, and glutamic oxaloacetic transaminase were decreased (P＜0.05 or P＜0.01), while the level of glucose was increased (P＜0.05). The collagen fibers were increased in myocardial tissue, and ultrastructure of myocardial cells was abnormal. Conclusion: Antiretrovirals during gestation can cause cardiovascular diseases in female rats.

Exosome-mediated delivery of SCD-1 siRNA promoted the death of anaplastic thyroid carcinoma cells via regulating ROS level

PURPOSE

Anaplastic thyroid carcinoma (ATC) is one of the most aggressive cancers in the world. Stearoyl-CoA desaturase-1 (SCD-1) is one of major enzymes in the de novo synthesis of fatty acids and is related to cancer aggressiveness and poor patient prognosis. The study aimed to construct exosomes loaded SCD-1 interference, investigate its effects and mechanisms on the cell proliferation and apoptosis of ATC cells.

METHODS

The expressions of SCD-1 in normal thyroid cell line and ATC cell lines were determined by qRT-PCR and western blotting, respectively. Exosomes were prepared and purification then loaded with SCD-1 siRNA by electroporation and observed by transmission electron microscopy. Higher SCD-1 mRNA and protein levels were found in ATC cell lines compared than normal thyroid cell line (P < 0.05), and both Hth-7 and FRO cells could uptake PKH67-labeled exosomes. The effects of exosomes loaded SCD-1 siRNA on ATC cells were measured by CCK8 assay and apoptosis detection kit.

RESULTS

When compared with control group, the cell viability significantly decreased in both two ATC cell lines taken up exosomes loaded SCD-1 siRNA (P < 0.001), and apoptotic and necrotic cells obviously increased (P < 0.05). In order to explore the mechanism of exosomes loaded SCD-1 on ATC, the ROS level was detected by fluorescence reagent. It was found that exosomes loaded SCD-1 siRNA significantly increased intracellular ROS level of ATC cells (P < 0.05).

CONCLUSIONS

Exosomes loaded SCD-1 siRNA inhibited ATC cellular proliferation and promoted cellular apoptosis, and the mechanisms involved maybe the regulation of fatty acids metabolism and ROS level. Our study provides a promising therapeutic strategy for ATC.

[Exposure to famine in fetus and infant period and risk for hypertension in adulthood]

Objective: To investigate the relationship between exposure to famine in fetus and infant period and the risks for hypertension in adulthood. Methods: A total of 5 960 participants born between 1956 and 1965 were included in the study and were divided into unexposed group (1963-1965), fetal exposed group (1959-1961), early- childhood exposed group (1956-1958) and transitional group (1962). Logistic regression model was used to explore the association between famine exposure in early life and the risk for hypertension in adulthood. Results: Both the fetal exposure and the early-childhood exposure were the risk factors for hypertension in adulthood (OR=1.249, 95%CI: 1.049-1.486 and OR=1.360, 95%CI: 1.102-1.679). Meanwhile, in rural area, compared with unexposed group, the fetal exposure (OR=1.401, 95%CI: 1.091-1.798) and the early-childhood exposure (OR=1.460, 95%CI: 1.145-1.862) were also associated with a greater risk of hypertension in adulthood. In addition, fetal exposure and early-childhood exposure to famine in women were associated with 36.0% and 31.9% increased risks for hypertension (95%CI: 7.8%-71.7% and 95%CI: 4.8%-66.0%) according to the stratified analysis. Conclusion: Fetal exposure to famine might increase the risk for hypertension in adulthood.

Complete plastid genome of Dendrobium naungmungense (Orchidaceae)

Dendrobium is one of the most important genera in Orchidaceae. In this study, we used the next-generation sequencing technology and assembled a complete plastid genome of a recently published new species of Dendrobium, D. naungmungense. The plastome was 151,883 bp in length, containing a large single-copy region (LSC) of 87,189 bp, and a small single-copy region (SSC) of 12,150 bp, and two inverted repeat regions (IR) of 26,272 bp. A total of 123 genes were predicted, including 38 tRNA genes, 8 rRNA genes, and 77 protein-coding genes. Phylogenetic analysis of 44 representative plastome of the genus Dendrobium and outgroup suggested D. naungmungense to be sister to Dendrobium wardianum.

[Comparative analysis of sleep monitoring between young and middle-aged and elderly OSA patients]

Objective:The aim of this study is to compare the night sleep hypoxia degree and sleep structure of young and middle-aged and elderly patients with OSA, so that PSG has more important application value.Method:A total of 438 patients diagnosed with OSA from February 2017 to January 2019 were selected,including 119 patients in the youth group with an average age of (28.5±5.1）years,and 319 patients in the middle and elderly group with an average age of (45.8±2.7)years.The results recorded by PSG in the two groups were retrospectively analyzed. Result:①The AHI, ODI, OAI, MAI and ASaO₂of OSA patients in the junior group were significantly higher than those in the middle-aged and elderly group, while CAI was not statistically significant between the two groups (P=0.419).②The NREM stage Ⅰ (61.1±4.3)% in the junior group was significantly higher than that in the junior group (53.3±3.4)%.NREM stage Ⅱ (33.2±2.3)% and NREM stage Ⅲ+Ⅳ (4.3±1.3)% in the junior group were higher than those in the middle-aged group (29.2±3.9)% and stage Ⅲ+Ⅳ (2.6±0.9)%, while the percentage of REM stage and microarousal index were not statistically significant between the two groups.③Young OSA patients were associated with hypertension and 47.0% middle-aged and elderly patients were associated with hypertension.There was no statistical difference between the two groups in whether hypertension was associated with hypertension or not.Conclusion:The NREM phase is particularly susceptible to age, and age affects slow wave sleep. The sleep structure of middle-aged and older people demonstrates their sleep characteristics: reduced total sleep time,slow wave sleep,low sleep efficiency,and delayed sleep. The young people's nighttime hypoxia is more serious. AHI,ODI,OAI,MAI,ASaO₂ and other indicators are significantly higher than the middle-aged and elderly people, but the sleep structure 2 groups are similar, indicating that young people have strong sleep physiological compensation and Adjustment ability.

[Vestibular function test in patients sudden sensorineural hearing loss patients with vertigoand its clinical significance]

Objective:The aim of this study is to analyze the results of vestibular function tests and clinical value of patients with sudden sensorineural hearing loss （SSHL） and vertigo. Method:Twelve cases（24 ears） of unilateral SSHL with vertigo were included in the study group. 11 age and sex matched normal subjects（22 ears） were recruited as the normal control group. Both patients and normal subjects underwent carolic tests, ocular vestibular evoked myogenic potential （oVEMP）, and cervical vestibular evoked myogenic potential （cVEMP） in bilateral ears. The results were compared between the subjects and the normal control group. Result: The rate of positive oVEMP was 25.0% in the affected ear and 50.0% in the contralateral ear in patients with SSHL and vertigo, and 90.9% in normal subjects; while the rate of positive cVEMP was 58.3% in the affected ear and 58.3% in the contralateral ear in patients with SSHL and vertigo, and 90.9% in normal subjects. There were no significant differences between the affected and contralateral ears （P>0.05）. Compared to normal subjects, oVEMP and cVEMP in both the affected and contralateral ears were significantly reduced （P<0.05）. The parameters of oVEMP and cVEMP （N1 latency, P1 latency, amplitudes） were not significantly different among the groups（P<0.05）. Compared to normal subjects, the threshold difference of oVEMP and cVEMP in both the affected and contralateral ears werehigher than the normal subjects（P<0.05）. Among 12 SSHL patients who underwent caloric test, 9 were found with unilateral semicircular canal weakness（CP>25%）, and the abnormal rate was 75% （9/12）. Conclusion:Patients with vertigo with vertigo have impaired conduction function in the ipsilateral and contralateral vestibular pathways, mainly due to decreased vestibular evoked myogenic potential, increased threshold, and abnormal cold and heat tests. The vestibular function test provides an objective basis for assessing the inner ear injury in patients with vertigo.

Novel Synthesis of Calix[N]Arene Amidoazobenzene Derivatives

A series of calix[ n]arenas and calix[4]resorciarenes containing azo chromophores on the lower rim were synthesised with two routes. The first direct route involved alkylating calixarenes with 4-chloroacetoaminoazobenzene. The second indirect route was by acylating 4-aminoazobenzene with calix[ n]arylacetyl chloride. Their extracting abilities for transition metal ions were tested.

[Brief discussion of history of vascular surgery in New China]

The history of vascular surgery in new China could be divided into the following three stages: the first stage, since the early 1980s, the technique of endovascular surgery was introduced in China, developed in some major hospitals, and gradually popularized to some basic hospitals conditionally. Vascular surgery had gradually developed into an independent discipline in China by the late 1980s. The second stage, since the late 1980s, vascular diagnosis and treatment technology, vascular equipment, and related research modification had been improving continuously in China, and achieved certain success, especially since the establishment of the department of vascular surgery affiliated to the Chinese Medical Association in 1993, vascular surgery in China representing its period of primary development. The third stage, since the beginning of the 21st century, the innovation of the technique of endovascular surgery and hybridization technology, and the development of materials technology had contributed to the second leaping forward of vascular surgery in China. Since then, vascular surgery enters a new era of minimally invasive surgery and opens a period of rapid development.

[Analysis of the recurrence related factors of sinonasal inverted papilloma]

Objective:To evaluate the influence risk factors of recurrence and the methods for reducing recurrence of sinonasal inverted papilloma (SNIP). Method:Clinical data of 34 patients with SNIP were analyzed retrospectively. All of them were unilateral onset. The diagnosis was confirmed pathologically and the range of lesions was determined by endoscopic and imaging examination; clinical classification according to Krouse classification method; All operations were performed under nasal endoscope, of which 20 cases were operated by simple nasal endoscope, and 14 cases were operated by endoscopic anterior lacrimal recess approach. The patients were followed up for 12-36 months. The curative effects were observed and the prognostic factors of the patients were analyzed. Result:Thirty-four cases of SNIP patients with postoperative recurrence rate was 17.65% (6/34); simple nasal endoscopic surgery in 20 cases, the recurrence rate was 25.00%(5/20); endoscopic anterior lacrimal recess approach in 14 cases, the recurrence rate was 7.14%(1/14), the difference was statistically insignificant (χ²=1.807, P>0.05). Four cases in stage Ⅰ had no recurrence；20 cases in stage Ⅱ, the recurrence rate was 15.0%(3/20); 9 cases in stage Ⅲ, the recurrence rate was 33.3%(3/9); 1 case in stage Ⅳ had no recurrence, the recurrence rate of the patients with different stages were statistically insignificant (χ²=2.692, P>0.05). Conclusion:Simple endoscopic resection of the tumor and endoscopic anterior lacrimal recess surgery are effective methods for the treatment of SNIP. The nasal surgery history and tumor origin are the risk factors for recurrence. The operation completely tumorresection,detailed preoperative examination and postoperative regular endoscopic examination are the keys to preventing recurrence.

[Two cases of piriform pit carcinoma were repaired with thyroid lobe]

Two cases with piriform fossa cancer underwent larynx lateral wall repair surgery. Case 1: The patient was admitted to the hospital because of pharyngeal discomfort with swallowing pain for 2 months Electronic laryngoscopy revealed neoplasm in the left piriform fossa. Space occupying lesion in left piriform fossa and paranasal space was found in MRI scan. The pathological diagnosis of this patient was squamous cell squamous cell carcinoma (T2N1M0). Case 2: The patient was admitted to the hospital because of blood in the sputum for more than 1 year. The electronic laryngoscope suggested neoplasm in the pharyngeal space and left vocal cord paralysis.Soft tissue thickening of the oropharynx and hypopharyngeal right wall was found in MRI scan. The pathological diagnosis of this patient was squamous cell carcinoma (T1N2M0).

[Various choices of reconstructing the left subclavicular artery to extend the proximal landing zone thoracic endovascular aortic repair]

Thoracic endovascular aortic repair (TEVAR) has become the preferred treatment for Stanford type B aortic dissection. Covered the left subclavian artery (LSA) directly may cause corresponding complications in Stanford type B aortic dissection with unfavourable proximal landing zone. TEVAR can be successfully implemented by reconstructing LSA to expand the proximal landing zone. Currently, the methods of reconstructing LSA mainly include hybridization technology (carotid-subclavian artery transposition), chimney technology (including branch stent technology) and fenestration (or slot technology), etc. These techniques are all valid for aortic dissection that needs to reconstructing LSA. The choices and applications of these techniques should follow the individualized principles.

[Research progress of Lgr5-positive stem cells in the formation of organoid in 3D culture]

Stem cell is critical to regeneration of tissue or organ of human. How to promote repair or regeneration in the tissues/organ using its pluripotency is always an important issue. Lgr5-possitive cell is one type of the stem cell-like cells capable of pluripotent differentiation in various tissues/organs of both humans and mice. Current study showed that single or small amount Lgr5-possitive stem cells can grow and form a plurality of organs in 3D culture system, and some organs can present similar biological and physiological properties with the progenitor they were derived. These studies provided new insight into future orientation, for example, Lgr5-possitive inner ear cells were confirmed as inner ear pluripotent cells population, the experiences obtained from organoid studies of Lgr5-possitive cells have certainly showed potential in the future study of inner ear stem cells. This review will focus on the recent progress associated with Lgr 5-positive stem cells forming organoids in the 3D culture.

[Effect of three types of rapid maxillary expansion: a three-dimensional finite element study]

Objective: To evaluate the transverse displacement, stress distribution and tendency of change in tooth, alveolar bone and mid-palatal suture using three kinds of rapid maxillary expansion methods. Methods: Cone-beam CT image data was obtained by scanning skulls of a volunteer. Three-dimensional models of maxillary complex were re-established using Mimics and Geomagic Studio and models of Hyrax expander, Haas expander and miniscrew-assisted rapid palatal expander (MARPE) were established using ANSYS Workbench. Stress distribution, displacement and tendency of change in tooth, alveolar bone and mid-palatal suture were evaluated. Results: Hyrax expander brought 0.105 mm lateral displacement of crown, 0.022 mm mid-palatal suture width increase, wedge opening and clockwise rotation tendency of maxilla. Haas expander created uniform stress distribution, 0.216 mm lateral displacement of crown, and 0.031 mm mid-palatal suture width increase. In MARPE model, the lateral displacement of crown was 0.267 mm, and mid-palatal suture width increased 0.315 mm. The maximum of mid-palatal suture expansion and stress distribution appeared in the middle region, and maxilla had tendency of counterclockwise rotation. Conclusions: The lateral changes of teeth and bones brought by MARPE were the most significant. Haas expander had some advantages in comparison with Hyrax.

Polyketides with different post-modifications from desert endophytic fungus Paraphoma sp

Three new polyketides 4,6,8-trihydroxy-5-methyl-3,4-dihydronaphthalen-1(2H)-one (1), 5,7-dihydroxy-3-(1-hydroxyethyl)-3,4-dimethylisobenzofuran-1(3H)-one (2) and 1-(4-hydroxy-6-methoxy-1,7-dimethyl-3-oxo-1,3-dihydroisobenzofuran-1-yl) ethyl acetate (3) together with seven known analogues (4-10) were isolated from desert endophytic fungus Paraphoma sp. The structures of these compounds were elucidated by analysis of NMR data. The absolute configuration of (1-3) was established on the basis of CD experiments. The possible biosynthetic pathway of compounds (1-10) was suggested, which implied that these secondary metabolites might be originated from polyketide biosynthesis with different post-modification reactions. Compounds 2, and 5-8 were evaluated for bioactivities against plant pathogen A. solani, whereas none of them displayed any biological effects. In addition, compounds 1, 2 and 5-10 were also tested for cytotoxic activities against three human cancer cell lines (HepG2 cells, MCF-7 cells and Hela cells) without biological effects.

[Efficacy and safety analysis of ivabradine hydrochloride treatment of Chinese patients with chronic heart failure: subgroup analysis of Chinese patients in the SHIFT study]

Objective: To evaluate the efficacy and safety of ivabradine for the treatment of Chinese patients with chronic heart failure based on the Chinese subgroup data of the systolic heart failure treatment with the I(f) inhibitor ivabradine trial (SHIFT). Method: A total of 6 558 stable outpatients who presented symptoms of heart failure, with a left ventricular ejection fraction (LVEF) ≤35%, sinus rhythms with a heart rate ≥70 bpm participated in the randomized, double-blind, placebo-controlled, international multicenter clinical study.The subset of Chinese patients with heart rate ≥75 bpm was enrolled in the post-hoc subgroup analyses.Patients were randomly allocated by computer-generated assignment through a telephone interactive voice response system to ivabradine group (starting dose 5 mg bid, which was then uptitrated to the maximum 7.5 mg bid) or matched placebo group.The clinical baseline characteristics of participants were obtained and analyzed.The primary outcome endpoint was a composite endpoint of cardiovascular death or hospitalization resulting from worsening HF.The primary safety endpoint included total incidence of adverse events during the study, bradycardia, and adverse visual reaction (phosphenes). Results: A total of 49 Chinese centers enrolled a total of 225 patients with chronic heart failure, of whom, 106 patients were randomized to the ivabradine group and the other 119 patients to the placebo group, and the mean follow-up time was (15.6±5.1) months.By the end of the study, mean heart rate (71.0 bpm vs. 80.3 bpm, P<0.05) and incidence of the primary endpoint events (18.9% (20/106) vs. 31.9%(38/119), HR=0.56, 95%CI 0.33-0.97, P=0.039) were significantly lower, while the percentage of patients with improvement in heart functional class NYHA (53.8% (56/106) vs. 34.5% (41/119), P=0.006 1) was significantly higher in the ivabradine group than in the placebo group.The total number of adverse events (129 events, 49.6% PY) in the ivabradine group was lower than that in the placebo group (203 events, 50.8% PY). In the ivabradine group and the placebo group, there were respectively 2 patients (1.9%) and 0 patients experienced bradycardia, 3 patients (2.9%) and 1 patient (0.8%) experienced adverse visual reaction (phosphenes). Conclusions: Ivabradine significantly reduced heart rate and improved the clinical outcomes and NYHA function class in Chinese patients with chronic heart failure, these beneficial effects are achieved without inducing remarkable adverse reactions.The results of Chinese subgroup analysis were thus consistent with the overall results of the SHIFT study. Clinical Trial Registry: International standard randomized controlled trials registry, ISRCTN 70429960.

Exogenous NO depletes Cd-induced toxicity by eliminating oxidative damage, re-establishing ATPase activity, and maintaining stress-related hormone equilibrium in white clover plants

Various nitric oxide (NO) regulators [including the NO donor sodium nitroprusside (SNP), the NO scavenger 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO), the NO-synthase inhibitor N (G)-nitro-L-Arg-methyl ester (L-NAME), and the SNP analogues sodium nitrite/nitrate and sodium ferrocyanide] were investigated to elucidate the role of NO in white clover (Trifolium repens L.) plants after long-term (5 days) exposure to cadmium (Cd). A dose of 100 μM Cd stress significantly restrained plant growth and decreased the concentrations of chlorophyll and NO in vivo, whereas it disrupted the balance of stress-related hormones and enhanced the accumulation of Cd, thereby inducing reactive oxygen species (ROS) burst. However, the inhibition of plant growth was relieved by 50 μM SNP through its stimulation of ROS-scavenging compounds (ascorbic acid, ascorbate peroxidase, catalase, glutathione reductase, non-protein thiol, superoxide dismutase, and total glutathione), regulation of H(+)-ATPase activity of proton pumps, and increasing jasmonic acid and proline but decreasing ethylene in plant tissues. Even so, the alleviating effect of SNP on plant growth was counteracted by cPTIO and L-NAME and was not observed with SNP analogues, suggesting that the protective roles of SNP are related to the induction of NO. These results suggest that NO may improve the Cd tolerance of white clover plants by eliminating oxidative damage, re-establishing ATPase activity, and maintaining hormone equilibrium. Improving our understanding of the role of NO in white clover plants is key to expanding the plantations to various regions and the recovery of pasture species in the future.

Defective bone repair in mast cell deficient mice with c-Kit loss of function

KitW-sh mice carry an inactivating mutation in the gene encoding the receptor for stem cell factor, which is expressed at high levels on the surface of haematopoietic precursor cells. The mutation results in mast cell deficiency, a variety of defects in innate immunity and poorly defined abnormalities in bone. The present study was designed to characterise healing of a cortical window defect in skeletally mature KitW-sh mice using high-resolution micro computed tomographic imaging and histological analyses. The cortical bone defect healed completely in all wild type mice but failed to heal in about half of the KitW-sh mice by 12 weeks post-operative. Defective healing was associated with premature and excessive expression of TRAP positive cells embedded in fibrous marrow but with little change in ALP activity. Immuno-histochemical analyses revealed reduced CD34 positive vascular endothelial cells and F4/80 positive macrophages at 1 and 2 weeks post-operative. Impaired bone healing in the KitW-sh mice was therefore attributed to altered catabolic activity, impaired re-vascularisation and compromised replacement of woven with compact bone.

Four pairs of gene-gene interactions associated with increased risk for type 2 diabetes (CDKN2BAS-KCNJ11), obesity (SLC2A9-IGF2BP2, FTO-APOA5), and hypertension (MC4R-IGF2BP2) in Chinese women

Metabolic disorders including type 2 diabetes, obesity and hypertension have growing prevalence globally every year. Genome-wide association studies have successfully identified many genetic markers associated to these diseases, but few studied their interaction effects. In this study, twenty candidate SNPs from sixteen genes are selected, and a lasso-multiple regression approach is implemented to consider the SNP–SNP interactions among them in an Asian population. It is found out that the main effects of the markers are weak but the interactions among the candidates showed a significant association to diseases. SNPs from genes CDKN2BAS and KCNJ11 are significantly associated to risk for developing diabetes, and SNPs from FTO and APOA5 might interact to play an important role for the onset of hypertension.

Multiplex polymerase chain reaction assay for the detection of minute virus of mice and mouse parvovirus infections in laboratory mice

Mouse parvoviruses are among the most prevalent infectious pathogens in contemporary mouse colonies. To improve the efficiency of routine screening for mouse parvovirus infections, a multiplex polymerase chain reaction (PCR) assay targeting the VP gene was developed. The assay detected minute virus of mice (MVM), mouse parvovirus (MPV) and a mouse housekeeping gene (α-actin) and was able to specifically detect MVM and MPV at levels as low as 50 copies. Co-infection with the two viruses with up to 200-fold differences in viral concentrations can easily be detected. The multiplex PCR assay developed here could be a useful tool for monitoring mouse health and the viral contamination of biological materials.

Lysine restriction and realimentation affected growth, blood profiles and expression of genes related to protein and fat metabolism in weaned pigs

To investigate the effects of lysine restriction and subsequent realimentation on growth performance, blood profiles and gene expression of leptin and myostatin, 128 weaned pigs [initial body weight (BW) 6.96 ± 1.07 kg, 26 ± 2 days of age] were randomly allotted to four treatments. The starter diets during the first 2 weeks (P1) contained 100%, 80%, 70% or 60% of recommended lysine levels (National Research Council, 1998). Then, common grower 1 and 2 diets were offered for 2 weeks (P2 and P3) each. During P1, average daily gain (ADG) was linearly reduced (p < 0.05) with the increasing levels of lysine restriction. Growth rate was greater in pigs previously fed lysine-restricted diets than well-fed pigs although it did not reach a significant level during realimentation. However, the final BW and overall ADG were the lowest (p < 0.05) and F/G was poor in pigs fed 60% lysine diet. Relative visceral organ weights and composition of skeletal muscle were similar (p > 0.05) among the treatment. Blood triglyceride and glucose levels were increased (p < 0.05) during P1, while blood urine nitrogen, total protein and albumin levels were decreased (p < 0.05) during P2 with the reduction in dietary lysine levels. The abundance of myostatin mRNA in skeletal muscle and leptin mRNA in subcutaneous adipose tissue were lower (p < 0.05) in lysine-restricted pigs than in pigs fed non-restricted diets. In conclusion, 80% and 70% lysine restriction of starter diets resulted in inferior growth and compensatory growth effect was noted during realimentation, while 60% lysine restriction had a negative influence on growth performance. Moreover, the changes in myostatin and leptin mRNA abundance caused by nutritional manipulations may be involved in the regulation of protein and fat deposition in young pigs.

Interaction between synchronous bilateral prophylactic oophorectomy and adjuvant chemotherapy in female patients with locally advanced colorectal cancer

AIM

In this study we explored the prognostic impact of synchronous bilateral prophylactic oophorectomy in female patients with primary colorectal cancer undergoing radical surgery.

METHOD

From 1991 to 2000, 267 female patients with stage II or stage III colorectal cancer, who had undergone curative resection, were retrospectively reviewed. In 224 patients, the ovaries were preserved. The other 43 patients underwent synchronous bilateral prophylactic oophorectomy. Univariate and multivariate analyses (Kaplan-Meier and Cox regression, respectively) were used to evaluate the effect of prophylactic oophorectomy and other clinical factors on the prognosis of patients.

RESULTS

Both univariate and multivariate analyses showed that tumor stage and adjuvant chemotherapy were the only two significant clinical factors that affected the 5-year overall survival of patients (P < 0.01). There was no significant difference in the 5-year overall survival between patients who had, or had not, undergone prophylactic oophorectomy (75%vs 73%, P > 0.05). In the subgroup analysis by adjuvant chemotherapy, the 5-year overall survival in patients receiving adjuvant chemotherapy was similar between nonoophorectomy and oophorectomy groups. However, in patients without adjuvant chemotherapy, the oophorectomy group was shown to have a significantly better 5-year overall survival than the nonoophorectomy group (76%vs 51%, P = 0.047).

CONCLUSION

Prophylactic oophorectomy may improve the overall survival of female patients with locally advanced colorectal cancer without adjuvant chemotherapy, but its survival benefit vanished in patients receiving adjuvant chemotherapy. The role of prophylactic oophorectomy may be substituted by adjuvant chemotherapy, which makes prophylactic oophorectomy unnecessary during surgery for locally advanced colorectal cancer.

Au nanoparticle monolayers: preparation, structural conversion and their surface-enhanced Raman scattering effects

An environment-friendly method is developed to fabricate close-packed Au nanoparticle (AuNP) monolayers with sub-10 nm interparticle spacing simply by covering n-butanol on the surface of an Au aqueous colloid. The close-packed nanostructure can further transform into two-dimensional (2D) aggregates with different aggregation degrees upon aging for several days. This structural evolution process was disclosed by transition electron microscopy (TEM) and UV-vis spectroscopy and its influence on the ensemble optical properties was further demonstrated by surface-enhanced Raman scattering (SERS). It was revealed that creating sub-10 nm interparticle spacing and particle dimers are highly desirable for engendering strong SERS activity under a 632.8 nm excitation. Further aging the film leads to the formation of larger aggregates, which moves the surface plasmon resonance of the aggregates gradually 'off-resonance' from the 632.8 nm excitation line and costs some numbers of sub-10 nm interparticle spacings. The two parameters together decrease the SERS activity of the close-packed AuNP monolayers. The present strategy thus provides an easy way to finely tune the SERS properties of thin nanoparticle films and other ensemble properties, which can easily be realized by creating sub-10 interparticle spacing, controlling the particle aggregation degree and by adopting suitable particle sizes and shapes.

Early energy and protein reduction: effects on growth, blood profiles and expression of genes related to protein and fat metabolism in broilers

1. A total of 320-d-old Ross broilers were used in a 6-week study to investigate the effects of feeding lower energy and protein diets from d 8 to 14 on growth performance, blood profiles, and gene expression of leptin and myostatin. 2. Broilers were randomly allotted to 4 treatments, each treatment applied to 4 pens with 20 birds in each. During first week, all the birds were fed on a common starter diet (13.4 MJ ME/kg, 230 g/kg CP and 11.0 g/kg lysine). The birds were then subjected to their respective treatment diets from d 8 to 14. Treatment diets comprised two ME levels, 13.4 and 12.0 MJ/kg, each with two levels of CP, 230 and 184 g/kg. This was followed by feeding common starter and finisher diets for the last 4 weeks. 3. Dietary protein reduction resulted in poor performance and feed efficiency while energy reduction resulted in poor feed efficiency between d 8 and 14. From d 14 to 42 birds previously fed diets lower in energy and protein showed similar body weight gain and feed intake to well-fed birds. Moreover from d 8 to 14, birds fed on energy and protein-reduced diets had lower nutrient metabolisability coefficients. 4. The blood urea nitrogen (BUN) and relative weights of heart and breast muscle were lower in birds fed protein-reduced diets while energy reduction resulted in lower plasma glucose, abdominal fat and intestinal weight at d 14. At d 42, birds fed on the protein-reduced diets had lower BUN, breast muscle weight and small intestine length, while feeding on the energy-reduced diets resulted in lower abdominal fat. 5. Upregulated myostatin mRNA expression in breast muscle and downregulation of leptin mRNA expression in abdominal fat were observed in birds fed on protein and energy-reduced diets, respectively. 6. In conclusion, early nutrient reduction affected growth performance and produced lesser abdominal fat in broilers. Moreover, early energy and/or protein reduction could change muscle and fat metabolism by regulating the expressions of myostatin and leptin.

Effects of metabolizable energy and lysine restrictions on growth performance, blood profiles, and expression of myostatin and leptin genes in broilers

To investigate the effects of metabolizable energy and lysine restriction on performance, and gene expression of leptin and myostatin, three hundred twenty day-old Ross broiler chicks were randomly allotted to four treatments. Birds were subjected to their respective diets comprising two levels of ME (3200; 2880 kcal kg-1) and two levels of lysine (1.10; 0.88%) during days 8 to 21. The dietary crude protein levels were reduced with the proportion to the lysine levels, while ratios of essential amino acids relative to lysine were similar for all diets. During restriction, weight gain, breast muscle and abdominal fat yield were lower in birds fed lysine-restricted diets. Relative myostatin mRNA abundance was increased in breast muscle of lysine-restricted birds, while expression of leptin mRNA in abdominal fat was downregulated by energy and lysine restriction. During realimentation, birds previously fed with energy and/or lysine-restricted diets had comparable performance as birds fed unrestricted diets. At day 42, energy and lysine restriction increased relative myostatin mRNA expression in breast muscle and birds previously fed diet restricted in both energy and lysine had the highest relative myostatin mRNA expression (energy × lysine interaction, P < 0.001). The relative leptin mRNA abundance was significantly lower in birds previously fed energy-restricted diets. These results indicated that early energy and lysine restriction from day 8 to 21 exhibited growth compensation during realimentation. In addition, myostatin and leptin mRNA expression in breast muscle and abdominal fat were modulated by nutritional treatments and were closely associated with changes in breast muscle yield and abdominal fat deposition. Key words: Metabolizable energy, lysine, myostatin, leptin, broiler

Rapid fabrication of large-area nanoparticle monolayer films via water-induced interfacial assembly

Close-packed nanoparticle monolayer films have been assembled at the water/toluene interface, and they can be transferred onto various hydrophilic solid substrates. The method involves adding alcohol and then toluene (when the dispersant is itself alcohol, only toluene was added) into a hydrophilic nanoparticle dispersion, and then a large quantity of distilled water was rapidly poured into the mixed system. Simultaneously, nanoparticles in the dispersion were extracted to the water/toluene interface, forming a thin film with a metallic sheen. The close-packed structures of these thin films were verified by transmission electron microscopy (TEM) characterizations. This method can work well for those hydrophilic nanoparticles without strongly bonded stabilizers, such as citrate-stabilized Au nanoparticles, polyvinylpyrrolidone (PVP)-stabilized Pt or Ag nanoparticles, and SiO(2) microspheres. Large-area nanoparticle monolayer films (e.g., more than 200 cm(2)) could be prepared in less than 10 s. Due to its inherent simplicity and speed, the method should be of significance for the nanofilm industry.

The morphological and physiological properties of the genetic tumours from a Nicotiana interspecific hybrid

Many plant tumours have been loosely referred to as genetic tumours when no obvious external cause was identifiable. In this study, the morphology of genetic tumours was detected by scanning electron microscopy (SEM) and the influence of exogenous phytohormones on genetic tumour growth was examined. Genetic tumours in Nicotiana hybrid were first observed in the hypocotyl area and later appeared from stems as a cluster complex. In vitro, genetic tumours were produced 5-6 days after explant treatment near each of the cut ends. The morphology of genetic tumours was investigated using SEM. Genetic tumours are mainly composed of epidermal cells surrounded by a well developed extracellular matrix (ECM), that is organized in a network linking surface cells. Globular structures containing several cells were formed from these clusters of epidermal cells. Vigorous tumourous growth from the leaf discs of the Nicotiana hybrid was obtained on medium supplemented with auxin and cytokinin at 0 to 10 muM, but 100 muM of auxin and cytokinin inhibited genetic tumour growth. Leaf discs treated with 10 muM cytokinin or auxin alone produced genetic tumours, but 10 muM cytokinin supplemented with 100 muM auxin stopped growth. Therefore genetic tumours are tissues that are, clearly, disturbed in endogenous hormone balance or have altered sensitivity to hormones and response to exogenous hormones.

Quantifying hepatic shear modulus in vivo using acoustic radiation force

The speed at which shear waves propagate in tissue can be used to quantify the shear modulus of the tissue. As many groups have shown, shear waves can be generated within tissues using focused, impulsive, acoustic radiation force excitations, and the resulting displacement response can be ultrasonically tracked through time. The goals of the work herein are twofold: (i) to develop and validate an algorithm to quantify shear wave speed from radiation force-induced, ultrasonically-detected displacement data that is robust in the presence of poor displacement signal-to-noise ratio and (ii) to apply this algorithm to in vivo datasets acquired in human volunteers to demonstrate the clinical feasibility of using this method to quantify the shear modulus of liver tissue in longitudinal studies. The ultimate clinical application of this work is noninvasive quantification of liver stiffness in the setting of fibrosis and steatosis. In the proposed algorithm, time-to-peak displacement data in response to impulsive acoustic radiation force outside the region of excitation are used to characterize the shear wave speed of a material, which is used to reconstruct the material's shear modulus. The algorithm is developed and validated using finite element method simulations. By using this algorithm on simulated displacement fields, reconstructions for materials with shear moduli (mu) ranging from 1.3-5 kPa are accurate to within 0.3 kPa, whereas stiffer shear moduli ranging from 10-16 kPa are accurate to within 1.0 kPa. Ultrasonically tracking the displacement data, which introduces jitter in the displacement estimates, does not impede the use of this algorithm to reconstruct accurate shear moduli. By using in vivo data acquired intercostally in 20 volunteers with body mass indices ranging from normal to obese, liver shear moduli have been reconstructed between 0.9 and 3.0 kPa, with an average precision of +/-0.4 kPa. These reconstructed liver moduli are consistent with those reported in the literature (mu = 0.75-2.5 kPa) with a similar precision (+/-0.3 kPa). Repeated intercostal liver shear modulus reconstructions were performed on nine different days in two volunteers over a 105-day period, yielding an average shear modulus of 1.9 +/- 0.50 kPa (1.3-2.5 kPa) in the first volunteer and 1.8 +/- 0.4 kPa (1.1-3.0 kPa) in the second volunteer. The simulation and in vivo data to date demonstrate that this method is capable of generating accurate and repeatable liver stiffness measurements and appears promising as a clinical tool for quantifying liver stiffness.

Quadruple-bend achromatic low emittance lattice studies

A quadruple-bend achromatic (QBA) cell, defined as a supercell made of two double-bend cells with different outer and inner dipole bend angles, is found to provide a factor of 2 in lowering the beam emittance relative to the more conventional double-bend achromat. The ratio of bending angles of the inner dipoles to that of the outer dipoles is numerically found to be about 1.5-1.6 for an optimal low beam emittance in the isomagnetic condition. The QBA lattice provides an advantage over the double-bend achromat or the double-bend nonachromat in performance by providing a small natural beam emittance and some zero-dispersion straight sections. A lattice with 12 QBA cells and a preliminary dynamic aperture study serves as an example.

Genetic dissection of ethanol tolerance in the budding yeast Saccharomyces cerevisiae

Uncovering genetic control of variation in ethanol tolerance in natural populations of yeast Saccharomyces cerevisiae is essential for understanding the evolution of fermentation, the dominant lifestyle of the species, and for improving efficiency of selection for strains with high ethanol tolerance, a character of great economic value for the brewing and biofuel industries. To date, as many as 251 genes have been predicted to be involved in influencing this character. Candidacy of these genes was determined from a tested phenotypic effect following gene knockout, from an induced change in gene function under an ethanol stress condition, or by mutagenesis. This article represents the first genomics approach for dissecting genetic variation in ethanol tolerance between two yeast strains with a highly divergent trait phenotype. We developed a simple but reliable experimental protocol for scoring the phenotype and a set of STR/SNP markers evenly covering the whole genome. We created a mapping population comprising 319 segregants from crossing the parental strains. On the basis of the data sets, we find that the tolerance trait has a high heritability and that additive genetic variance dominates genetic variation of the trait. Segregation at five QTL detected has explained approximately 50% of phenotypic variation; in particular, the major QTL mapped on yeast chromosome 9 has accounted for a quarter of the phenotypic variation. We integrated the QTL analysis with the predicted candidacy of ethanol resistance genes and found that only a few of these candidates fall in the QTL regions.

The effects of continuous epidural analgesia on Doppler velocimetry of uterine arteries during different periods of labour analgesia

BACKGROUND

The transient effects of epidural bupivacaine 0.25-0.5% on the Doppler velocimetry of umbilical and uterine arteries had been reported, but the effects of continuous lower dose epidural bupivacaine (0.05-0.1%) infusion for labour analgesia have never been reported. In this study, we evaluated the effects of continuous epidural bupivacaine 0.075% on the Doppler velocimetry of uterine arteries.

METHODS

Twenty pregnant women for labour analgesia received continuous epidural bupivacaine 0.075% infusion. We used a 4-MHz continuous-wave Doppler probe (Multigon 500A) with a 200 Hz thump filter to detect uterine blood flow velocity. We recorded the velocimetry data for uterine relaxation and contraction during five time periods: pre-epidural insertion, 1, 2, and 4 h post-epidural infusion, and after delivery of fetus.

RESULTS

Our data showed that the velocimetric indices of uterine vascular resistance were significantly increased 1, 2, and 4 h after epidural infusion when compared with the pre-epidural level; these returned to the baseline after delivery.

CONCLUSION

Continuous epidural analgesia with bupivacaine 0.075% increases the resistance of uterine artery and therefore possibly reduces the uterine blood flow.

The synergetic effects of two CCAAT boxes in Aspergillus niger glaA gene promoter on activation of PglaA transcription

EMSA and footprinting analyses have revealed that the -489-- -414 bp and the -390-- -345 bp (designated DC and PC respectively) upstream of the Aspergillus nigerT21 glaA gene were bound by one protein factor in the A. nigerT21 whole cell extract. Both DC and PC contained CCAAT pentanucleotides. The functions of DC and PC in regulation of expression of glucoamylase (GLA) were studied. CCAAT pentanucleotides were replaced with CGTAA and the mutated DNA fragments DCm and PCm lost the binding activities of protein factors in vitro. In vivo when either DC or PC was mutated or the relative orientations between them were changed on the PglaA, the transcriptional activity of PglaA decreased to a basal level. Introduction of multi-copies of DC into the original site at the PglaA in A. nigerT21 decreased the expression of endogenous GLA expression and the exogenous reporter E. coli uidA gene introduced under the PglaA promoter, while having no effect on the uidA gene under the control of PgpdA. EMSA revealed that the levels of the specific DNA-binding protein factors in the transformants maintained the same meaning that introduction of multi-copies of DC caused the titration effect. AnghapC gene was cloned from A. nigerT21 cDNA and introduced into the DC multi-copied strains. The expression of AnghapC improved the expression of the endogenous GLA and the exogenous gene controlled by PglaA. These results showed that both the CCAAT pentanucleotides were necessary for DC and PC binding to the protein factors, and the simultaneous binding of DC and PC to the protein was necessary for promoting the transcriptional activity of PglaA. AngHapC was the specific positive trans-acting protein factor binding to DC.

Extension neural network and its applications

In this paper, a novel extension neural network (ENN) is proposed. This new neural network is a combination of extension theory and neural network. It uses an extension distance (ED) to measure the similarity between data and cluster center. The learning speed of the proposed ENN is shown to be faster than the traditional neural networks and other fuzzy classification methods. Moreover, the new scheme has been proved to have high accuracy and less memory consumption. Experimental results from two different examples verify the effectiveness and applicability of the proposed work.

Short-term ceftriaxone therapy for treatment of severe non-typhoidal Salmonella enterocolitis

AIM

To evaluate the clinical efficacy of a short-course ceftriaxone therapy in the treatment of paediatric patients with severe non-typhoidal Salmonella enterocolitis.

METHODS

During a 1 y period, all paediatric patients who were suspected having Salmonella enterocolitis by the presentation of bloody and/or mucoid diarrhoea with or without fever were eligible for the study. Patients with either negative stool cultures or bacteraemia were excluded. Severe enterocolitis was defined as a bloody and/or mucoid diarrhoea associated with high fever persisting for longer than 48 h and signs of moderate or severe dehydration. The patients with severe enterocolitis were assigned to treatment with ceftriaxone (50 mg kg(-1) d(-1)) for 3-5 d, while the rest were given supportive treatment only. Before treatment all study patients received blood testing for white blood cell (WBC) count, C-reactive protein (CRP) level and blood culture. The duration of the fevers was recorded. Patients were followed up after clinical recovery for the possibility of relapse.

RESULTS

Seventy-three patients with culture-confirmed Salmonella enterocolitis without bacteraemia were analysed. The duration of fever was longer in severe cases who were treated with ceftriaxone than those who were not. However, rapid defervescene was found after short-course ceftriaxone therapy in those patients with severe enterocolitis. CRP was significantly higher in severe cases. There was no significant difference in the WBC count between the two groups of patients. No relapse was found in these patients.

CONCLUSION

High CRP, prolonged high fever and signs of moderate or severe dehydration appear appropriate to define severe cases of Salmonella enterocolitis. Short-course ceftriaxone therapy is clinically beneficial to these patients. Neither clinical nor microbiological relapse was seen after therapy.

Modulation by 20-HETE of phenylephrine-induced mesenteric artery contraction in spontaneously hypertensive and Wistar-Kyoto rats

Small mesenteric arteries of spontaneously hypertensive (SHR) and Wistar-Kyoto rats (WKY) were compared for the production of 20-HETE and the effects of 20-HETE and N-methylsulfonyl-12,12-dibromododec-11-enamide (DDMS, 30 micromol/L), a 20-HETE synthesis inhibitor, on contractile responsiveness to phenylephrine (0.1 to 50.0 micromol/L). 20-HETE production was higher in vessels of SHR compared with WKY (1.34+/-0.16 versus 0.27+/-0.09 pmol/mg tissue, P<0.05). Phenylephrine elicited concentration-dependent vascular contraction; the R(max) was similar in vessels of SHR and WKY, but the former were more sensitive as denoted by the lower EC(50) (1.10+/-0.14 versus 1.89+/-0.33 micromol/L, P<0.05). DDMS caused a rightward shift in the concentration-response curve to phenylephrine, increasing (P<0.05) the EC(50) by 258% and 134% in vessels of SHR and WKY, respectively. In contrast, in DDMS-treated vessels, 20-HETE (0.01 to 10.0 micromol/L) caused a leftward shift in the phenylephrine concentration-response curve, decreasing (P<0.05) the EC(50) without affecting the R(max). Importantly, the minimal concentration of 20-HETE that decreased the EC(50) of phenylephrine was much smaller in vessels of SHR that of WKY (0.01 versus 1.0 micromol/L). We conclude that 20-HETE increases the sensitivity of mesenteric arterial vessels to phenylephrine, vessels of SHR are more sensitive to this action of the eicosanoid than vessels of WKY, and vessels of SHR produce more 20-HETE than do vessels of WKY. Hence, 20-HETE of vascular origin may be a determinant of the increased reactivity to constrictor agonists in the vasculature of SHR.

Cutaneous B cell lymphoma in a Mongolian gerbil (Meriones unguiculatus)

A mass was noticed on the right mandible of an aged male Mongolian gerbil. Because of rapid enlargement of the mass, the animal was euthanized and submitted for pathology. The mass was firm, pink in color, 15 mm in diameter, and tightly adherent to adjacent tissues. Staining with hematoxylin and eosin revealed that the mass was a lymphoid tumor. Neoplastic cells had a large, round, dense nuclei and little cytoplasm. The tumor contained numerous mitotic figures. Immunohistochemical stains showed that the neoplastic cells expressed CD19 and IgM but lacked CD3 and CD5. Flow cytometric analysis showed that the neoplastic cells were positive for B220, IgG, and CD40. We concluded that the tumor was a primary cutaneous B cell lymphoma. In addition, the antibodies we used for the present diagnosis were anti-mouse reagents; therefore, they also were useful for subtyping gerbil lymphoid cells.

Diffractively produced charm final states in 800-GeV/c pp collisions

We report the first observation of diffractively produced open charm in 800-GeV/c pp collisions of the type pp-->pD*X. We measure cross sections of sigma(diff)(D*+) = (0.185+/-0.044+/-0.054) (mu)b and sigma(diff)(D(*-)) = (0.174+/-0.034+/-0.029) (mu)b. Our measurements are based on 4.3x10(9) events recorded by FNAL E690 in the fixed-target run of 1991. We compare our results with previous fixed-target charm experiments.

Ron-mediated cytoplasmic signaling is dispensable for viability but is required to limit inflammatory responses

Ron receptor activation induces numerous cellular responses in vitro, including proliferation, dissociation, and migration. Ron is thought to be involved in blood cell development in vivo, as well as in many aspects of the immune response including macrophage activation, antigen presentation, and nitric oxide regulation. In previous studies to determine the function of Ron in vivo, mice were generated with a targeted deletion of the extracellular and transmembrane regions of this gene. Mice homologous for this deletion appear to die early during embryonic development. To ascertain the in vivo function of Ron in more detail, we have generated mice with a germline ablation of the tyrosine kinase domain. Strikingly, our studies indicate that this domain of Ron, and therefore Ron cytoplasmic signaling, is not essential for embryonic development. While mice deficient in this domain are overtly normal, mice lacking Ron signaling have an altered ability to regulate nitric oxide levels and, in addition, have enhanced tissue damage following acute and cell-mediated inflammatory responses.