Corrigendum: Seed coat pattern QTL and development in cowpea (Vigna unguiculata [L.] Walp.)

[This corrects the article DOI: 10.3389/fpls.2019.01346.].

[A dry-reagent assay to rapidly detect Mycobacterium tuberculosis using loop-mediated isothermal amplification]

A molecular diagnostic assay which could be stored at room temperature was developed to rapidly detect Mycobacterium tuberculosis (MTB) based on loop-mediated isothermal amplification (LAMP) technology and dry-reagent process. LAMP uses 4 or 6 primers and Bst DNA polymerase to amplify DNA at a constant temperature. The results showed that the LAMP assay could detect the amplification of IS6110 target gene within 20 min using real-time fluorescence signal detection. The sensitive of LAMP assay was similar to the PCR technology while the precision of PCR was better than LAMP (coefficient of variation, LAMP 18.9%, PCR 3.4%), meaning LAMP was more suitable for qualitative detection. The LAMP assay did not amplify DNA of other 10 types of pathogens, including Neisseria meningitidis, Haemophilus influenzae, Staphylococcus aureus, Streptococcus pneumoniae, Rubivirus, mumps virus, adenovirus (type 3), adenovirus (type 7), respiratory syncytial virus B and parainfluenza virus type 2, indicating a good specificity. Furthermore, a dry-reagent assay was developed using air-drying and freeze-drying process. The performance of dried reagents did not change after 10 days storage at 50 ℃, meaning the dried reagents could be stored at room temperature (25 ℃) for more than six months. The dry-reagent LAMP assay also successfully amplified MTB DNA from several clinical samples within 20 min. In conclusion, the developed LAMP assay together with isothermal amplifier could rapidly detection MTB.

Panscleritis After Blunt Ocular Trauma in A Child with Epididymitis

We reported an 8-year-old boy with panscleritis in left eye and right epididymitis after falling on the ground. Etiologic diagnosis played a key role in this case. Systemic examinations ruled out systemic autoimmune diseases, tumors, and infections as the cause of scleritis and suggested that the disease was caused by a local delayed-type hypersensitivity (DTH) induced by ocular trauma and was non-infectious. Still, the right epididymitis was infectious. Both conditions were treated successfully using steroids and antibiotics, respectively. Thus, early etiologic diagnosis and reasonable treatment are crucial to prevent visual loss.

Plantamajoside attenuates cardiac fibrosis via inhibiting AGEs activated-RAGE/autophagy/EndMT pathway

Advanced glycation end products (AGEs) have been identified to transduce fibrogenic signals via inducing the activation of their receptor (RAGE)-mediated pathway. Recently, disrupting AGE-RAGE interaction has become a promising therapeutic strategy for chronic heart failure (CHF). Endothelial-to-mesenchymal transition (EndMT) is close to the cardiac fibrosis pathological process. Our previous studies have demonstrated that knockout RAGE suppressed the autophagy-mediated EndMT, and thus alleviated cardiac fibrosis. Plantamajoside (PMS) is the major bioactive compound of Plantago Asiatica, and its activity of anti-fibrosis has been documented in many reports. However, its effect on CHF and the underlying mechanism remains elusive. Thus, we tried to elucidate the protective role of PMS in CHF from the viewpoint of the AGEs/RAGE/autophagy/EndMT axis. Herein, PMS was found to attenuate cardiac fibrosis and dysfunction, suppress EndMT, reduce autophagy levels and serum levels of AGEs, yet did not affect the expression of RAGE in CHF mice. Mechanically, PMS possibly binds to the V-domain of RAGE, which is similar to the interaction between AGEs and RAGE. Importantly, this competitive binding disturbed AGEs-induced the RAGE-autophagy-EndMT pathway in vitro. Collectively, our results indicated that PMS might exert an anti-cardiac fibrosis effect by specifically binding RAGE to suppress the AGEs-activated RAGE/autophagy/EndMT pathway.

[Analysis of the efficacy and safety of coblation and pulsed radiofrequency in the treatment of cervicogenic headache]

Objective: To explore the efficacy and safety of coblation and pulsed radiofrequency on cervicogenic headache (CEH). Methods: A total of 118 patients with CEH who underwent coblation or pulsed radiofrequency in the Department of Pain Management at Xuanwu Hospital, Capital Medical University from August 2018 to June 2020 was retrospectively collected. Patients were divided into the coblation group (n=64) and the pulsed radiofrequency group (n=54) according to different surgical methods. In the coblation group, there were 14 males and 50 females, aged 29-65 (49.8±10.2) years, while in the pulse radiofrequency group, there were 24 males and 30 females, aged 18-65 (41.7±14.8) years. Visual analogue scale (VAS) score, postoperative numbness in the affected areas and other complications were recorded and compared between the two groups at preoperative 3 d, and 1 month, 3 months and 6 months postoperatively. Results: The VAS score of the coblation group was (7.16±0.91), (3.67±1.13), (1.59±0.91), (1.66±0.84) and (1.56±0.90) before operation, and 3 days, 1 month, 3 months and 6 months after surgery. Likewise, the VAS score of the pulsed radiofrequency group was (7.01±0.78), (1.58±0.88), (1.57±0.94), (3.71±1.08) and (6.92±0.83) at the aforementioned time points. There were statistically significant differences of VAS scores between the coblation group and the pulsed radiofrequency group at 3 days, 3 months and 6 months postoperatively (all P<0.001). Intra-group comparison revealed that VAS scores in the coblation group were significantly lower than those before surgery at all time points after surgery (all P<0.001), while VAS scores in the pulsed radiofrequency group were significantly decreased at 3 days, 1 month and 3 months after surgery (P<0.001). The incidence of numbness was 72% (46/64), 61% (39/64), 6% (4/64) and 3% (2/62) in the coblation group and 7% (4/54), 7% (4/54), 2% (1/54) and 0 (0/54) in the pulsed radiofrequency group, respectively. At 3 days and 1 month after surgery, the incidence of numbness in the coblation group was higher than those in the pulsed radiofrequency group (both P<0.001). In the coblation group, one patient developed pharyngeal discomfort 3 days after surgery, which disappeared spontaneously 1 week after surgery without special treatment. One patient developed vertigo after getting up in the morning at 3 days postoperatively, and the possibility of transient cerebral ischemia was considered. In the pulsed radiofrequency group, one patient developed nausea and vomiting after operation, but spontaneous remission was observed after one hour without special treatment. Conclusions: Both coblation and pulsed radiofrequency are effective and safe in the treatment of CEH. But the VAS scores at 3 and 6 months after coblation is significantly lower than those of pulsed radiofrequency ablation group, and the efficacy is better in those undergoing coblation.

[Clinical analysis of 4 children with hereditary hypercholesterolemia]

Objective: To investigate the clinical characteristics of hereditary hypercholesterolemia in childhood. Methods: The clinical data including general conditions, clinical manifestations, laboratory tests, and genetic testing results of 4 children with hereditary hypercholesterolemia who admitted to Henan Children's Hospital from January 2020 to December 2020 were retrospectively analyzed. Results: There were 4 female children aged 5.5,1.5,6.3,3.1 years, all presented with skin xanthoxoma as the chief complaint. Plasma total cholesterol (range 11.8 to 20.9 mmol/L) and low density lipoprotein-cholesterol (range 8.2 to 13.7 mmol/L) were significantly elevated. The serum β-glutamate levels in case 1 (241.2 μmol/L) and case 2 (164.2 μmol/L) increased significantly. Genetic analysis revealed compound heterozygous variants of ABCG8 gene in case 1 and ABCG5 gene in case 2 who were diagnosed with sitosterolemia. Case 3 and 4 who all had family history of hypercholesterolemia and compound heterozygous variants of LDLR gene were diagnosed with familial hypercholesterolemia. After diet treatment, the blood lipids returned normal and the skin xanoma subsided in case 1 and 2. In case 3 and 4, the blood lipids gradually decreased after diet and rosuvastatin treatment. Conclusions: Xanthomatosis is the common clinical manifestation of sitosterolemia and familial hypercholesterolemia. Family history, blood plant sterol profile, genetic variation, and changes in blood lipids after early dietary treatment are helpful for disease identification.

[Dynamic analysis of tuberculosis specific mononuclear cells in peripheral blood of HIV patients with tuberculosis]

Objective: To evaluate the response of peripheral blood mononuclear cells (PBMCs) in patients with human immunodeficiency virus (HIV) combined with active tuberculosis (TB) to TB-specific antigen stimulation. Methods: From January to December, 2018, individuals infected with both HIV and TB (HIV/TB group) were taken as the study subjects. Individuals infected with HIV alone (HIV group), individuals infected with TB alone (TB group) and healthy people (Health control group, HC group) were taken as the control groups. PBMCs were isolated and stimulated with purified protein derivative of bacillus calmette-guerin (BCG-PPD). The expression of surface molecules in T cells (CD3⁺, CD4⁺, CD8⁺) and monocytes (CD14⁺) and the percentages of Interferon (IFN)-γ and tumor necrosis factor (TNF)-α were detected by cell surface molecular staining, direct intracellular cytokine staining and flow cytometry (CD3^- lymphocytes were mainly B lymphocytes and NK cells). Analysis of non-parametric data was used to compare the data between the two groups, and paired t-test was used to compare the data before and after PPD stimulation in each group. Results: Before PPD stimulation, the percentage of IFN-γ⁺ CD8⁺ cells in the peripheral blood of HIV/TB group(mean 0.52%) was significantly lower than that in TB group(mean 0.94%, P=0.010). The TNF-α⁺cell percentages in CD3⁺, CD4⁺, CD8⁺, or CD14⁺ cells in the HIV/TB group(mean 19.2%) were significantly lower than those in the HIV group(mean 31.9%, P=0.002). The percentage of TNF-α secreted by monocytes in the HIV group was significantly lower than that in the HC group. The percentages of IFN-γ⁺ CD8⁺ and IFN-γ⁺ CD3^- cells in the peripheral blood of the TB group (mean 0.94%) were significantly higher than thoset in the HC group(mean 0.51%, P=0.020), while the percentages of TNF-α⁺ cells in each subsets of PBMCs were significantly lower than those in the HC group. After PPD stimulation, the percentage of IFN-γ⁺ CD8⁺ cells in the HIV/TB group was significantly lower than that in the TB group(P=0.008), and the change was more marked than that before stimulation. The percentage of IFN-γ⁺ CD8⁺ cells in the HIV group(mean 0.20%) was lower than that in the HC group (mean 0.52%, P=0.044). The percentage of IFN-γ⁺ CD3^- in the TB group was significantly higher than in the HC group. There were no significant differences in TNF-α⁺ cell percentages in the 3 groups compared with the control group after PPD stimulation. The percentages of IFN-γ⁺ CD4⁺ cells in the HC and the TB groups were significantly increased after PPD stimulation in each group (P=0.002, P=0.001, respectively). However, there were no significant differences of IFN-γ⁺ CD4⁺ cell percentages in the HIV/TB group and the HIV group. The percentages of TNF-α production by monocytes were significantly increased after PPD stimulation in all groups. Conclusions: Chronic Mycobacterium tuberculosis (MTB) infection reduced the ability of PBMCs to produce TNF-α. For patients with TB infection, the production of TNF-α was reduced when combined with HIV infection. The capacity of CD8⁺ and CD3^- lymphocytes to produce IFN-γ was increased in TB patients, while the capacity of CD8⁺ T cells to produce IFN-γ was decreased with co-infection of HIV. Infection of HIV weakened the immune response to MTB infection, which made the clinical diagnosis and treatment of TB more difficult.

Chondrocyte apoptosis in temporomandibular joint osteoarthritis promotes bone resorption by enhancing chemotaxis of osteoclast precursors

OBJECTIVE

This study aimed to explore the effect and mechanism of chondrocyte apoptosis on the chemotaxis of osteoclast precursors (OCPs) during bone destruction.

DESIGN

The relationship between cartilage and bone destruction was verified with a rat temporomandibular joint osteoarthritis (TMJOA) model. The pan-caspase inhibitor Z-VAD-FMK (ZVAD) was applied to confirm the chemotactic effect of chondrocyte apoptosis on OCPs. Synthesis and release of the key chemokine CX3CL1 in apoptotic and non-apoptotic chondrocytes was assessed with IHC, IF, WB, and ELISA. The function of CX3CL1-CX3CR1 axis in the chemotaxis of OCPs was examined by CX3XR1 inhibitor AZD8797 (AZD) and si-CX3CL1. The regulatory effect of p38 MAPK on CX3CL1 release was verified by p38 inhibitor PH-797804.

RESULTS

A temporal and spatial association between cartilage degradation and bone resorption was found in the TMJOA model. The caspase-dependent chondrocyte apoptosis promoted chemotaxis of OCPs, which can be restrained by ZVAD. CX3CL1 was significantly upregulated when chondrocytes underwent apoptosis, and it played a critical role in the recruitment of OCPs, blockage of CX3CL1-CX3CR1 axis resulted in less bone resorption in TMJOA. P38 MAPK was activated in apoptotic chondrocytes, and had a regulatory effect on the synthesis and release of CX3CL1. After inhibition of p38 by PH-797804, the chemotactic effect of apoptotic chondrocytes on OCPs was limited.

CONCLUSIONS

This study indicates that apoptosis of chondrocytes in TMJOA enhances chemotaxis of OCPs toward osteoclast precursors through upregulation of the p38-CX3CL1 axis, thereby promoting the activation of local osteoclasts.

Seed Coat Pattern QTL and Development in Cowpea (Vigna unguiculata [L.] Walp.)

The appearance of the seed is an important aspect of consumer preference for cowpea (Vigna unguiculata [L.] Walp.). Seed coat pattern in cowpea has been a subject of study for over a century. This study makes use of newly available resources, including mapping populations, a reference genome and additional genome assemblies, and a high-density single nucleotide polymorphism genotyping platform, to map various seed coat pattern traits to three loci, concurrent with the Color Factor (C), Watson (W), and Holstein (H) factors identified previously. Several gene models encoding proteins involved in regulating the later stages of the flavonoid biosynthesis pathway have been identified as candidate genes, including a basic helix-loop-helix gene (Vigun07g110700) for the C locus, a WD-repeat gene (Vigun09g139900) for the W locus and an E3 ubiquitin ligase gene (Vigun10g163900) for the H locus. A model of seed coat development, consisting of six distinct stages, is described to explain some of the observed pattern phenotypes.

A Novel Root-Knot Nematode Resistance QTL on Chromosome Vu01 in Cowpea

The root-knot nematode (RKN) species Meloidogyne incognita and M. javanica cause substantial root system damage and suppress yield of susceptible cowpea cultivars. The narrow-based genetic resistance conferred by the Rk gene, present in some commercial cultivars, is not effective against Rk-virulent populations found in several cowpea production areas. The dynamics of virulence within RKN populations require a broadening of the genetic base of resistance in elite cowpea cultivars. As part of this goal, F1 and F2 populations from the cross CB46-Null (susceptible) x FN-2-9-04 (resistant) were phenotyped for M. javanica induced root-galling (RG) and egg-mass production (EM) in controlled growth chamber and greenhouse infection assays. In addition, F[Formula: see text] families of the same cross were phenotyped for RG on field sites infested with Rk-avirulent M. incognita and M. javanica The response of F1 to RG and EM indicated that resistance to RKN in FN-2-9-04 is partially dominant, as supported by the degree of dominance in the F2 and F[Formula: see text] populations. Two QTL associated with both RG and EM resistance were detected on chromosomes Vu01 and Vu04. The QTL on Vu01 was most effective against aggressive M. javanica, whereas both QTL were effective against avirulent M. incognita Allelism tests with CB46 x FN-2-9-04 progeny indicated that these parents share the same RKN resistance locus on Vu04, but the strong, broad-based resistance in FN-2-9-04 is conferred by the additive effect of the novel resistance QTL on Vu01. This novel resistance in FN-2-9-04 is an important resource for broadening RKN resistance in elite cowpea cultivars.

Deep ultraviolet light-emitting diodes with improved performance via nanoporous AlGaN template

We report the performance enhancement of AlGaN-based deep ultraviolet light-emitting diodes (DUV LEDs) using AlGaN nanoporous template (NPT). The NPT was fabricated by the electrochemical etching method and served as the dislocation filtering layer and strain relieving layer. The n-AlGaN laterally regrown on NPT showed reduced dislocation density and mitigated compressive strain comparing with that on the as-grown template (AGT). A 23% improvement of internal quantum efficiency was achieved for the multiple quantum wells thereon. Moreover, the nanopores in the NPT transformed into elongated air voids during high temperature growth process, which could facilitate the escaping of photons by scattering and thus improve the light extraction efficiency. As a consequence, the DUV LED based on NPT demonstrated an increase of the light outpower by 50% at 20 mA than that on AGT.

Identification of QTL controlling domestication-related traits in cowpea (Vigna unguiculata L. Walp)

Cowpea (Vigna unguiculata L. Walp) is a warm-season legume with a genetically diverse gene-pool composed of wild and cultivated forms. Cowpea domestication involved considerable phenotypic changes from the wild progenitor, including reduction of pod shattering, increased organ size, and changes in flowering time. Little is known about the genetic basis underlying these changes. In this study, 215 recombinant inbred lines derived from a cross between a cultivated and a wild cowpea accession were used to evaluate nine domestication-related traits (pod shattering, peduncle length, flower color, days to flowering, 100-seed weight, pod length, leaf length, leaf width and seed number per pod). A high-density genetic map containing 17,739 single nucleotide polymorphisms was constructed and used to identify 16 quantitative trait loci (QTL) for these nine traits. Based on annotations of the cowpea reference genome, genes within these regions are reported. Four regions with clusters of QTL were identified, including one on chromosome 8 related to increased organ size. This study provides new knowledge of the genomic regions controlling domestication-related traits in cowpea as well as candidate genes underlying those QTL. This information can help to exploit wild relatives in cowpea breeding programs.

A multi-parent advanced generation inter-cross (MAGIC) population for genetic analysis and improvement of cowpea (Vigna unguiculata L. Walp.)

Multi-parent advanced generation inter-cross (MAGIC) populations are an emerging type of resource for dissecting the genetic structure of traits and improving breeding populations. We developed a MAGIC population for cowpea (Vigna unguiculata L. Walp.) from eight founder parents. These founders were genetically diverse and carried many abiotic and biotic stress resistance, seed quality and agronomic traits relevant to cowpea improvement in the United States and sub-Saharan Africa, where cowpea is vitally important in the human diet and local economies. The eight parents were inter-crossed using structured matings to ensure that the population would have balanced representation from each parent, followed by single-seed descent, resulting in 305 F₈ recombinant inbred lines each carrying a mosaic of genome blocks contributed by all founders. This was confirmed by single nucleotide polymorphism genotyping with the Illumina Cowpea Consortium Array. These lines were on average 99.74% homozygous but also diverse in agronomic traits across environments. Quantitative trait loci (QTLs) were identified for several parental traits. Loci with major effects on photoperiod sensitivity and seed size were also verified by biparental genetic mapping. The recombination events were concentrated in telomeric regions. Due to its broad genetic base, this cowpea MAGIC population promises breakthroughs in genetic gain, QTL and gene discovery, enhancement of breeding populations and, for some lines, direct releases as new varieties.

Implant dentistry in Australia: the present and future. A survey of Australian dentists and specialists

BACKGROUND

In recent years, implant dentistry has become a routine part of many general dental practices in Australia. However, there has been little information regarding its extent and scope. This investigation aimed to address this issue by surveying Australian general dental practitioners (GDP) and relevant specialists regarding their practice of implant dentistry.

METHODS

Anonymous electronic surveys were designed online using SurveyMonkey™ and delivered to the following professional bodies: all seven state/territory branches of the Australian Dental Association, the Australian and New Zealand Academy of Periodontists, the Australian and New Zealand Academy of Oral and Maxillofacial Surgeons, and prosthodontist members of the Australian Prosthodontic Society. The surveys were completed online via SurveyMonkey in 2014.

RESULTS

The response rates were 7.61% (N = 801) for GDP, 41.76% (N = 38) for prosthodontists, 34.16% (N = 55) for periodontists and 34.07% (N = 46) for oral and maxillofacial (OMF) surgeons. Among the respondents, 66.37% (N = 521) of GDP, 86.11% (N = 31) of prosthodontists, 82.98% (N = 39) of periodontists and 97.67% (N = 42) of OMF surgeons indicated that they currently practise implant dentistry. A strong perceived need for further education in this field was also expressed by the respondents.

CONCLUSIONS

Implant dentistry presently appears to be practised by a significant proportion of GDP across Australia. This is likely to continue to grow in the future.

Genome resources for climate-resilient cowpea, an essential crop for food security

Cowpea (Vigna unguiculata L. Walp.) is a legume crop that is resilient to hot and drought-prone climates, and a primary source of protein in sub-Saharan Africa and other parts of the developing world. However, genome resources for cowpea have lagged behind most other major crops. Here we describe foundational genome resources and their application to the analysis of germplasm currently in use in West African breeding programs. Resources developed from the African cultivar IT97K-499-35 include a whole-genome shotgun (WGS) assembly, a bacterial artificial chromosome (BAC) physical map, and assembled sequences from 4355 BACs. These resources and WGS sequences of an additional 36 diverse cowpea accessions supported the development of a genotyping assay for 51 128 SNPs, which was then applied to five bi-parental RIL populations to produce a consensus genetic map containing 37 372 SNPs. This genetic map enabled the anchoring of 100 Mb of WGS and 420 Mb of BAC sequences, an exploration of genetic diversity along each linkage group, and clarification of macrosynteny between cowpea and common bean. The SNP assay enabled a diversity analysis of materials from West African breeding programs. Two major subpopulations exist within those materials, one of which has significant parentage from South and East Africa and more diversity. There are genomic regions of high differentiation between subpopulations, one of which coincides with a cluster of nodulin genes. The new resources and knowledge help to define goals and accelerate the breeding of improved varieties to address food security issues related to limited-input small-holder farming and climate stress.

Influence of eutrophication on the distribution of total mercury and methylmercury in hydroelectric reservoirs

The distribution of mercury (Hg) and the characteristics of its methylation were investigated in Wujiangdu (WJD) and Yinzidu (YZD) reservoirs in Guizhou province, China. The two reservoirs are characterized by high and low levels of primary productivity, respectively. Mercury species in water samples from depth profiles in both reservoirs and from interface water in the WJD were analyzed each season during 2007. The concentrations of total Hg (HgT(unf)) and methylmercury (MeHgT(unf)) in unfiltered water samples from the WJD varied from 3.0 to 18 pmol dm(-3) and from 0.17 to 15 pmol dm(-3), respectively; ranges were 2.0 to 9.5 pmol dm(-3) for HgT(unf) and 0.14 to 2.2 pmol dm(-3) for MeHgT(unf) in the YZD. Elevated methylmercury concentrations in water samples from the bottom water and water-sediment interface demonstrated an active net Hg methylation in the downstream reach of the WJD. There was no discernable Hg methylation occurring in the YZD, nor in the upstream and middle reaches of the WJD. The results suggest that high primary productivity resulting from cage aquaculture activities in the WJD is an important control on Hg methylation in the reservoir, increasing the concentrations of MeHg in water in the Wujiang River basin Southwestern China.

Evolution of Wurtzite Structured GaAs Shells Around InAs Nanowire Cores

GaAs was radially deposited on InAs nanowires by metal-organic chemical vapor deposition and resultant nanowire heterostructures were characterized by detailed electron microscopy investigations. The GaAs shells have been grown in wurtzite structure, epitaxially on the wurtzite structured InAs nanowire cores. The fundamental reason of structural evolution in terms of material nucleation and interfacial structure is given.

Anomalous line shape of the cross section for e{+}e{-}--> hadrons in the center-of-mass energy region between 3.650 and 3.872 GeV

We observe an obvious anomalous line shape of the e;{+}e;{-}--> hadrons total cross sections in the energy region between 3.700 and 3.872 GeV. It is inconsistent with the explanation for only one simple psi(3770) resonance with a statistical significance of 7sigma. The anomalous line shape may be explained by two possible enhancements of the inclusive hadron production near the center-of-mass energies of 3.764 and 3.779 GeV, indicating that either there is likely a new structure in addition to the psi(3770) resonance around 3.773 GeV, or there are some physics effects reflecting the DD[over ] production dynamics.

Search for the invisible decay of J/psi in psi(2S) --> pi(+)pi(-) J/psi

Using psi(2S) --> pi(+)pi(-) J/psi events in a sample of 14.0 x 10(6) psi(2S) decays collected with the BES-II detector, a search for the decay of the J/psi to invisible final states is performed. No signal is found, and an upper limit at the 90% confidence level is determined to be 1.2 x 10(-2) for the ratio B(J/psi --> invisible)/B(J/psi-->mu(+)mu(-)). This is the first search for J/psi decays to invisible final states.

Observation of Y(2175) in J/psi --> etaphif0 (980)

The decays of J/psi --> etaphif(0)(980)[eta --> gammagamma, phi --> K(+) K(-), f(0)(980) --> pi(+)pi(-)] are analyzed using a sample of 5.8 x 10(7) J/psi events collected with the BESII detector at the Beijing Electron-Positron Collider. A structure at around 2.18 GeV/c(2) with about 5 sigma significance is observed in the phif(0)(980) invariant mass spectrum. A fit with a Breit-Wigner function gives the peak mass and width of m = 2.186+/-0.010(stat)+/-0.006(syst) GeV/c(2) and Gamma = 0.065+/-0.023(stat)+/-0.017(syst) GeV/c(2), respectively, which are consistent with those of Y(2175), observed by the BABAR Collaboration in the initial-state radiation process e(+)e(-) --> gamma(ISR) phif(0)(980). The production branching ratio is determined to be Br(J/psi --> etaY(2175))Br(Y(2175)- -> phif(0)(980))Br(f(0)(980) --> pi(+)pi(-)) = [3.23+/-0.75(stat)+/-0.73(syst)] x 10(-4), assuming that the Y(2175) is a 1(--) state.

Measurement of psi2S radiative decays

Using 14 x 10(6) psi(2S) events accumulated at the BESII detector, we report first measurements of branching fractions or upper limits for psi(2S) decays into gammapp, gamma2(pi+pi-), gammaKS0K+pi-+c.c., gammaK+K-pi+pi-, gammaK*0K-pi++c.c., gammaK*0K*0, gammapi+pi-pp, gamma2(K+K-), gamma3(pi+pi-), and gamma2(pi+pi-)K+K- with the invariant mass of hadrons below 2.9 GeV/c2. We also report branching fractions of psi(2S) decays into 2(pi+pi-)pi0, omegapi+pi-, omegaf2(1270), b1+/-pi-/+, and pi02(pi+pi-)K+K-.

Measurements of the continuum R(uds) and R values in e(+)e(-) annihilation in the energy region between 3.650 and 3.872 GeV

We report measurements of the continuum R(uds) near the center-of-mass energy of 3.70 GeV, the R[uds(c)+psi(3770)](s) and the R(had)(s) values in e(+)e(-) annihilation at 68 energy points in the energy region between 3.650 and 3.872 GeV with the BES-II detector at the BEPC Collider. We obtain the R(uds) for the continuum light hadron (containing u, d, and s quarks) production near the DD threshold to be R(uds)=2.141+/-0.025+/-0.085.

Search for invisible decays of eta and eta' in J/psi --> phi eta and phi eta'

Using a data sample of 58 x 10(6) J/psi decays collected with the Beijing Spectrometer II detector at the Beijing Electron Positron Collider, searches for invisible decays of eta and eta' in J/psi to phi eta and phi eta' are performed. The phi signals, which are reconstructed in K+K- final states, are used to tag the eta and eta' decays. No signals are found for the invisible decays of either eta or eta', and upper limits at the 90% confidence level are determined to be 1.65 x 10(-3) for the ratio B(eta-->invisible)/B(eta --> gamma gamma) and 6.69 x 10(-2) for B(eta' --> invisible)/B(eta' --> gammagamma). These are the first searches for eta and eta' decays into invisible final states.

Observation of a broad 1-- resonant structure around 1.5 GeV/c2 in the K+K- mass spectrum in J/psi-->K+K-pi0

A broad peak is observed at low K+K- invariant mass in J/psi-->K+K-pi(0) decays found in a sample of 5.8x10(7) J/psi events collected with the BESII detector. The statistical significance of the broad resonance is much larger than 5sigma. A partial wave analysis shows that the J;{PC} of this structure is 1--. Its pole position is determined to be [1576(-55)(+49)(stat)-91+98(syst)] MeV/c(2)-i/2[818(-23)(+22)(stat)-133+64(syst)] MeV/c(2). These parameters are not compatible with any known meson resonances.

Measurements of the branching fractions for psi(3770)-->D(0)D[over ](0), D+D-, DD[over ], and the resonance parameters of psi(3770) and psi(2S)

We measure the branching fractions for psi(3770)-->D(0)D[over ](0), D+D-, DD[over ], and non-DD[over ] to be (46.7+/-4.7+/-2.3)%, (36.9+/-3.7+/-2.8)%, (83.6+/-7.3+/-4.2)%, and (16.4+/-7.3+/-4.2)%, respectively. The resonance parameters of psi(3770) and psi(2S) are measured to be M_(psi(3770))=3772.2+/-0.7+/-0.3 MeV, Gamma_(psi(3770))(tot)=26.9+/-2.4+/-0.3 MeV, and Gamma_(psi(3770))(ee)=251+/-26+/-11 eV; M_(psi(2S))=3685.5+/-0.0+/-0.3 MeV, Gamma_(psi(2S))(tot)=331+/-58+/-2 keV, and Gamma_(psi(2S))(ee)=2.330+/-0.036+/-0.110 keV. We also measure the light hadron R value to be R(uds)=2.262+/-0.054+/-0.109 in the energy region from 3.660 to 3.872 GeV.

Observation of two new N* peaks in J/psi-->ppi-n and ppi+n decays

The decay J/psi-->NNpi provides an effective isospin 1/2 filter for the piN system due to isospin conservation. Using 58x10(6) J/psi decays collected with the Beijing Electromagnetic Spectrometer at the Beijing Electron Positron Collider, more than 100 thousand J/psi-->ppi-n+c.c. events are obtained. Besides the two well-known N* peaks at around 1500 MeV/c2 and 1670 MeV/c2, there are two new, clear N* peaks in the ppi invariant mass spectrum around 1360 MeV/c2 and 2030 MeV/c2 with statistical significance of 11sigma and 13sigma, respectively. We identify these as the first direct observation of the N*(1440) peak and a long-sought missing N* peak above 2 GeV/c2 in the piN invariant mass spectrum.

Observation of a near-threshold enhancement in the omega(phi) mass spectrum from the doubly OZI-suppressed decay J/psi-->gamma(omega)phi

An enhancement near threshold is observed in the omega(phi) invariant mass spectrum from the doubly Okubo-Zweig-Iizuka-suppressed decays of J/psi-->gamma(omega)phi, based on a sample of 5.8 x 10(7) J/psi events collected with the BESII detector. A partial wave analysis shows that this enhancement favors JP=0+, and its mass and width are M=1812(+19)(-26)(stat)+/-18(syst) MeV/c2 and Gamma=105+/-20(stat)+/-28(syst) MeV/c2. The product branching fraction is determined to be B(J/psi-->gammaX)B(X-->omega(phi))=[2.61+/-0.27(stat)+/-0.65(syst)]x10(-4).

Observation of a resonance in Chi(1835) in J/psi --> gammapi+ pi- eta-

The decay channel J/psi --> gamma(pi)(+)pi(-)eta is analyzed using a sample of 5.8 x 10(7) J/psi events collected with the BESII detector. A resonance, the Chi(1835), is observed in the pi(+)pi(-)eta invariant-mass spectrum with a statistical significance of 7.7 sigma. A fit with a Breit-Wigner function yields a mass M = 1833.7 +/- 6.1(stat) +/- 2.7(syst) MeV/c(2), a width Tau = 67.7 +/- 20.3(stat) +/- 7.7(syst) MeV/c(2), and a product branching fraction B(J/psi --> gammaChi) . B(Chi --> pi(+)pi(-)eta) = [2.2 +/- 0.4(stat) +/- 0.4(syst)] x 10(-4). The mass and width of the Chi(1835) are not compatible with any known meson resonance. Its properties are consistent with expectations for the state that produces the strong pp mass threshold enhancement observed in the J/psi --> gammapp process at BESII.

Observation of a threshold enhancement in the plambda invariant-mass spectrum

An enhancement near the m(p)+M(Lambda) mass threshold is observed in the combined pLambda and pLambda invariant-mass spectrum from J/psi-->pK(-)Lambda;+c.c. decays. It can be fit with an S-wave Breit-Wigner resonance with a mass m=2075+/-12(stat)+/-5(syst) MeV and a width of Gamma=90+/-35(stat)+/-9(syst) MeV; it can also be fit with a P-wave Breit-Wigner resonance. Evidence for a similar enhancement is also observed in psi(')-->pK(-)Lambda;+c.c. decays. The analysis is based on samples of 5.8x10(7)J/psi and 1.4x10(7)psi(') decays accumulated in the BES II detector at the Beijing Electron-Positron Collider.

Observation of the decay psi(2S)-->K0SK0L

The decay psi(2S)-->K(0)(S)K(0)(L) is observed using psi(2S) data collected with the Beijing Spectrometer at the Beijing Electron-Positron Collider; the branching fraction is determined to be B(psi(2S)-->K(0)(S)K(0)(L))=(5.24+/-0.47+/-0.48)x10(-5). Compared with J/psi-->K(0)(S)K(0)(L), the psi(2S) branching fraction is enhanced relative to the prediction of the perturbative QCD "12%" rule. The result, together with the branching fractions of psi(2S) decays to other pseudoscalar meson pairs (pi(+)pi(-) and K+K-), is used to investigate the relative phase between the three-gluon and the one-photon annihilation amplitudes of psi(2S) decays.

Observation of a near-threshold enhancement in the pp mass spectrum from radiative J/psi-->gammapp decays

We observe a narrow enhancement near 2m(p) in the invariant mass spectrum of pp pairs from radiative J/psi-->gammapp decays. No similar structure is seen in J/psi-->pi(0)pp decays. The results are based on an analysis of a 58 x 10(6) event sample of J/psi decays accumulated with the BESII detector at the Beijing electron-positron collider. The enhancement can be fit with either an S- or P-wave Breit-Wigner resonance function. In the case of the S-wave fit, the peak mass is below 2m(p) at M=1859(+3)(-10) (stat)+5-25(syst) MeV/c(2) and the total width is Gamma<30 MeV/c(2) at the 90% confidence level. These mass and width values are not consistent with the properties of any known particle.

Measurements of the cross section for e(+)e(-) --> hadrons at center-of-mass energies from 2 to 5 GeV

We report values of R = sigma(e(+)e(-)-->hadrons)/sigma(e(+)e(-)-->mu(+)mu(-)) for 85 center-of-mass energies between 2 and 5 GeV measured with the upgraded Beijing Spectrometer at the Beijing Electron-Positron Collider.

Electronmicroscopy studies on the opsonic role of antiserum and the subsequent destruction of Salmonellae within murine inflammatory leukocytes

Inbred female C3H mice were given, by intraperitoneal injection, 4 X 10(7) virulent Salmonella typhimurium organisms opsonised with specific antiserum. Peritoneal washings were obtained between 1.5 and 24 h after injection and examined by electronmicroscopy. Opsonised salmonellae were ingested rapidly by peritoneal exudate cells and were digested rapidly. The presence of antibody facilitated the phagocytic efficiency of the host cells. Destruction of ingested bacteria appeared to be an innate capacity of the host phagocytes independent of the presence of antibody.

Electronmicroscopy studies on the bactericidal action of inflammatory leukocytes in murine salmonellosis

Inbred female C3H mice were given 2 X 10(7) cfu virulent Salmonella typhimurium by intraperitoneal injection. Peritoneal washings were harvested between 3 h and 72 h after infection and examined by electronmicroscopy. There was evidence of intracellular killing by polymorphs and macrophages. The degeneration of intracellular salmonellae was seen initially as enlarging central electron-lucent areas in the cytoplasm and peripheral condensation of cytoplasmic granules, followed by disruption of the bacterial envelope and disintegration of cellular structure. Alternatively, the initial injury appeared as an irregular and discontinuous bacterial envelope with compression of the bacterium and diffuse condensation of cytoplasmic granules. It was also evident that virulent salmonellae multiplied extracellularly in the peritoneal cavity of the infected mice.

The effects of variations in pH and temperature on the activation of mouse thymocytes by both forms of rabbit interleukin-1

We studied the responses of unpurified mouse thymocytes and of peanut agglutinin-negative mouse thymocytes to the pI 7.3 form of rabbit Interleukin-1. We found that small increases of temperature strongly enhanced the mitogenic effect of this form of IL-1, and that the apparent temperature optimum was 37 degrees C. In both these respects the behavior of the pI 7.3 IL-1 resembled the previously described behavior of pI 5.0 IL-1. We suspected that the low apparent temperature optimum for IL-1 action was due to inadequate pH control by the bicarbonate-buffered medium. Experiments showed that small decreases in medium pH strongly inhibited the mitogenic action of both forms of IL-1. Furthermore, if thymocytes were stimulated with either form of IL-1 in strongly buffered media, the temperature optimum was at least 39 degrees C. The pI 7.3 and pI 5.0 forms of IL-1 are known to differ both biochemically and immunologically. Our experimental discovery that their temperature sensitivities are much the same suggests that temperature sensitivity is a property of the T cell rather than of the IL-1 molecules themselves.