Application of methyl jasmonate to control chilling tolerance of postharvest fruit and vegetables: a meta-analysis and eliciting metabolism review

Chilling injury is one of the most significant limitations for low temperature storage of postharvest fruits and vegetables, causing quality deterioration and economic loss. Increasing studies indicated that methyl jasmonate (MeJA) is critical in regulating the postharvest fruit and vegetables chilling tolerance. Based on a meta-analysis, the review analyzed the action of exogenous MeJA application on the chilling index in postharvest fruit and vegetables and summarized MeJA's mechanisms for controlling postharvest chilling injury. The meta-analysis found that MeJA treatment remarkably inhibited postharvest fruit and vegetable chilling injury. Moreover, we concluded the following function mechanism of MeJA on postharvest fruit and vegetable chilling tolerance: (1) Enhancing membrane integrity and energy supply, (2) Increasing antioxidant activity, (3) Enhancing arginine pathway, (4) Enhancing sugar metabolism, (5) Regulating phenolic metabolism, (6) Activating CBF pathway, (7) Regulating HSP accumulation and expression, and (8) Crosstalk with phytohormone. Finally, we summarized the regulatory mechanisms of MeJA on postharvest fruit and vegetable biological processes at the transcriptional and post-translational levels.

Interaction of methionine sulfoxide reductase B5 with SlMYC2 stimulates the transcription of MeJA-mediated autophagy-related genes in tomato fruit

Methyl jasmonate (MeJA) has been shown to induce autophagy in various plant stress responses and metabolic pathways. MYC2 is involved in MeJA-mediated postharvest fruit biological metabolism, but it is unclear how it affects MeJA-induced fruit autophagy. In this study, we noticed that silencing SlMYC2 significantly reduced the increase in autophagy-related genes (SlATGs) expression induced by MeJA. SlMYC2 could also bind to the promoters of several SlATGs, including SlATG13a, SlATG13b, SlATG18a, and SlATG18h, and activate their transcript levels. Moreover, SlMsrB5, a methionine sulfoxide reductase, could interact with SlMYC2. Methionine oxidation in SlMYC2 and mimicking sulfoxidation in SlMYC2 by mutation of methionine-542 to glutamine reduced the DNA-binding ability and transcriptional activity of SlMYC2, respectively. SlMsrB5 partially repaired oxidized SlMYC2 and restored its DNA-binding ability. On the other hand, silencing SlMsrB5 inhibited the transcript levels of SlMYC2-targeted genes (SlATG13a, SlATG13b, SlATG18a, and SlATG18h). Similarly, dual-luciferase reporter (DLR) analysis revealed that SlMsrB5-SlMYC2 interaction significantly increased the ability of SlMYC2-mediated transcriptional activation of SlATG13a, SlATG13b, SlATG18a, and SlATG18h. These findings demonstrate that SlMsrB5-mediated cyclic oxidation/reduction of methionine in SlMYC2 influences SlATGs expression. Collectively, these findings reveal the mechanism of SlMYC2 in SlATGs transcriptional regulation, providing insight into the mechanism of MeJA-mediated postharvest fruit quality regulation.

The Co-regulation of Ethylene Biosynthesis and Ascorbate-Glutathione Cycle by Methy Jasmonate Contributes to Aroma Formation of Tomato Fruit during Postharvest Ripening

Currently, many fruits are always harvested at the early ripening stage to reduce postharvest losses followed by 1-methylcyclopropene (1-MCP) or ethephon treatment. However, harvesting at the early ripening stage adversely affects fruit quality, especially for the aroma. Methyl jasmonate (MeJA) treatment could induce the biosynthesis of bioactive compounds and maintain postharvest fruit quality. In the present work, the contributions of MeJA to tomato fruit quality during postharvest ripening were studied. The results showed that MeJA treatment significantly promoted the accumulation of volatile organic components (VOCs) by inducing the activities of enzymes related to lipoxygenase pathway and ethylene biosynthesis, whereas 1-MCP treatment largely inhibited the accumulation of VOCs by inhibiting activities of those enzymes. Although the application of ethephon also induced activities of the above enzymes in comparison with control, no significant differences were observed between the VOCs contents of the control and ethephon-treated fruit. Further study revealed that the ethephon treatment resulted in the enhancement of electrical conductivity and malondialdehyde content. Conversely, MeJA treatment inhibited the superoxide anion radical and hydrogen peroxide by regulating the ascorbate-glutathione cycle and further inhibited the enhancement of electrical conductivity and malondialdehyde content, which might be one of the most important reasons why the VOCs contents in fruit treated with ethephon were lower than those in MeJA-treated fruit. Thus, it is considered that MeJA treatment may be an effective and promising strategy to regulate postharvest tomato fruit quality, especially for the aroma, by regulating the ascorbate-glutathione cycle and ethylene biosynthesis.

SlARG2 contributes to MeJA-induced defense responses to Botrytis cinerea in tomato fruit

BACKGROUND

Arginase plays key roles in methyl jasmonate (MeJA)-mediated quality maintenance in vegetables and fruits. MeJA treatment induced the Arginase 2 (SlARG2) expression, which is one of the most important encoding genes of arginase. In addition, the treatment with MeJA induced resistance to pathogenic infection in many plants. However, the functions of SlARG2 in MeJA-induced defense to Botrytis cinerea are unclear. In our work, control and SlARG2-silenced tomato fruits (Solanum lycopersicum) were treated with 0.05 mmoL L^-1 MeJA before storage to assay the roles of SlARG2 in MeJA-induced defense responses to Botrytis cinerea.

RESULTS

Our results indicated that MeJA treatment induced both pathogenesis-related gene expression (PR1, PR2a, PR2b and PR3b), and the activity of defense-related enzymes, as well as upregulated arginine metabolism. Compared to control fruits, the treatment with MeJA also induced the activity of arginase, arginine decarboxylase (ADC) and ornithine aminotransferase (OAT), and expression of SlARG2, SlADC, ornithine decarboxylase (SlODC) and SlOAT, and consequently increased the accumulation of arginine, proline, glutamate, putrescine and spermine. However, the induction effects by MeJA were significantly reduced in fruits in which SlARG2 was silenced and severe disease symptoms were observed.

CONCLUSION

MeJA fumigation could inhibit disease development by inducing pathogenesis-related gene expression (PR1, PR2a, PR2b and PR3b) and defense-related enzymes activity, as well as upregulated arginine metabolism. In addition, SlARG2 silencing could inhibit the functions of MeJA in inducing the accumulation of the above substances. Overall, our study provided strong evidence that SlARG2 was essential for MeJA-induced tomato fruit defense responses to Botrytis cinerea. © 2020 Society of Chemical Industry.

Potential anti-ageing effect of chondroitin sulphate through skin regeneration

OBJECTIVE

Skin ageing is inevitably exposed through its typical features such as wrinkles and sagging. Therefore, skin anti-ageing is a major issue in cosmetic research to prevent and improve ageing symptoms using effective ingredients. Chondroitin sulphate (CS), a type of glycosaminoglycan, is an important structural component of the extracellular matrix (ECM) and is involved in various biological processes, such as cell proliferation, differentiation and migration. Here, we aimed to investigate the effects of CS on skin regeneration and examine its efficacy as a potential safe and effective skin anti-ageing ingredient.

METHODS

We investigated the effects of CS on cell proliferation in normal human keratinocytes and fibroblasts. Then, cell migration, ECM synthesis and related signalling pathways were examined in fibroblasts through gene and protein expression analysis. Finally, the effect on skin wound healing and regeneration was validated using a full-thickness skin wound model and an aged skin model.

RESULTS

Chondroitin sulphate treatment increased the proliferation of keratinocytes and fibroblasts. It also stimulated the migration and synthesis of ECM components of fibroblasts. Further analysis revealed that CS induced the expression of type I procollagen by activating the extracellular signal-regulated kinase pathway. Using a full-thickness skin wound model and an aged skin model, we confirmed that CS treatment promoted skin wound healing and regeneration.

CONCLUSION

Together, our results indicated that CS has the potential to facilitate skin regeneration, implying that CS could be clinically applied to improve skin ageing.

The Synergism of 1-Methylcyclopropene and Ethephon Preserves Quality of "Laiyang" Pears With Recovery of Aroma Formation After Long-Term Cold Storage

A "Laiyang" pear is a climacteric fruit with a special taste and nutritional value but is prone to a post-harvest aroma compound loss and a loss in fruit quality. In this study, pears were pretreated with 0.5 μl L-1 1-methylcyclopropene (1-MCP) at 20°C for 12 h and then stored at 0 ± 1°C for 150 days to evaluate the influence of 1-MCP on fruit quality and the changes in components of volatile aromas. In addition, pears were further treated with 2 mmol L-1 ethephon. The effects of ethephon on the recovery of aroma production were investigated during the 150 day storage at 0 ± 1°C and the subsequent 7 day shelf life at 20 ± 1°C. Treatment with 1-MCP inhibited firmness loss, increased electrical conductivity, reduced respiration and ethylene production rates as well as the contents of soluble solids, and maintained the storage quality of the fruits. However, 1-MCP treatment inhibited the emission of volatile aromas in pear fruits by decreasing the activities of various enzymes, such as lipoxygenase (LOX), hydroperoxide lyase (HPL), alcohol dehydrogenase (ADH), pyruvate carboxylase (PDC), and alcohol acetyltransferase (AAT). During the shelf-life, activities of the above mentioned enzymes were significantly enhanced, and a higher content of volatile aromas were found in fruits treated with 1-MCP + ethephon, while other qualities were not compromised. These results showed that 1-MCP treatment could effectively maintain the quality of the "Laiyang" pear during cold storage, and the additional application of ethephon on fruits during shelf-life may be a promising way to restore volatile aromas in pear fruits after long-term storage.

CRISPR/Cas9-Mediated SlMYC2 Mutagenesis Adverse to Tomato Plant Growth and MeJA-Induced Fruit Resistance to Botrytis cinerea

Methyl jasmonate (MeJA), a natural phytohormone, played a critical role not only in plant growth but also in plant defense response to biotic and abiotic stresses. MYC2, a basic helix-loop-helix transcription factor, is a master regulator in MeJA signaling pathway. In the present work, slmyc2 mutants were generated by the clustered regularly interspaced short palindromic repeats and associated Cas9 protein (CRISPR/Cas9) system to investigate the role of SlMYC2 in tomato plant growth and fruit disease resistance induced by exogenous MeJA. The results showed that slmyc2 mutants possessed a higher number of flowers and a lower fruit setting rate in comparison with wild-type plants. In addition, the fruit shape of slmyc2 mutant was prolate, while the control fruits were oblate. Knockout of SlMYC2 significantly decreased the activities of disease defensive and antioxidant enzymes, as well as the expression levels of pathogen-related (PR) genes (SlPR-1 and SlPR-STH2) and the key genes related to jasmonic acid (JA) biosynthesis and signaling pathway including allene oxide cyclase (SlAOC), lipoxygenase D (SlLOXD), SlMYC2, and coronatine insensitive 1 (SlCOI1), and consequently aggravated the disease symptoms. By contrast, the disease symptoms were largely reduced in MeJA-treated fruit that possessed higher activities of these enzymes and expression levels of genes. However, the induction effects of MeJA on fruit disease resistance and these enzymes' activities and genes' expressions were significantly attenuated by knockout of SlMYC2. Therefore, the results indicated that SlMYC2 played positive regulatory roles not only in the growth of tomato plants but also in MeJA-induced disease resistance and the antioxidant process in tomato fruits.

The shape change index (SCI) of inferior vena cava (IVC) measuring by transabdominal ultrasound to predict the presence of septic shock in intensive care unit (ICU) patients

OBJECTIVE

This study is designed as prospective and observational research of patients with sepsis. It was carried out in the intensive care unit (ICU). We investigated the shape change index (SCI) of inferior vena cava (IVC) measured with trans-abdominal ultrasound to detect the signs of septic shock. The aim of this research was to find the most effective tool in predicting shock in patients compared with that of other parameters such as brain natriuretic peptide (BNP), lactate, variation index of inferior vena cava IVC-VI, and extravascular lung water index (EVLWI).

PATIENTS AND METHODS

We suppose that SCI can be used as the safest and most sensitive tool in the early recognition of septic dysfunction. The observational study was conducted in the Department of ICU, Shandong Provincial Hospital Affiliated to Shandong University from January 2016 to December 2017. SCI of IVC, serum lactate, BNP, IVC-VI, and EVLWI concentrations were measured in 30 sepsis patients. All studied biomarkers were analyzed and contrasted according to the score of the Sequential Organ Failure Assessment (SOFA). Pearson correlation analysis was analyzed to statistic the relationship between variables.

RESULTS

We showed the correlation of BNP value, lactic acid value, IVC-VI, EVLWI, and SCI of IVC in sick patients suffering septic shock. Positive correlation was observed in the BNP value, lactic acid value, IVC-VI, EVLWI, and SCI of IVC (r=0.447, p=0.013; r=0.484, p=0.007; r=0.423, p=0.023; r=0.638, p<0.001; r=0.599, p<0.001; respectively). However, the SCI and EVLWI showed a stronger correlation with the SOFA than the others. SCI of IVC, as estimated by transabdominal ultrasound, was more accurate than the other commonly used non-invasive predictors. EVLWI, as an accurate and classical predictor, was an invasive predictor. SCI of IVC was faster, more convenient and safer than the other.

CONCLUSIONS

SCI of IVC was faster, more convenient and safer than the other commonly used non-invasive predictors. Early recognition and diagnosis of sepsis may improve patient outcome.

Effect of methyl salicylate in combination with 1-methylcyclopropene on postharvest quality and decay caused by Botrytis cinerea in tomato fruit

BACKGROUND

Postharvest diseases result in major losses in fruits. Tomato is susceptible to postharvest rot caused by Botrytis cinerea and is regarded as a good model system to study postharvest disease and quality deterioration in fruit. To develop a safe and effective technique to alleviate disease and maintain fruit quality, the effects of methyl salicylate (MeSA) and 1-methylcyclopropene (1-MCP) either separately or combined on quality and gray mold caused by B. cinerea in tomato fruit were investigated.

RESULTS

The results showed that application of MeSA (0.05 mmol L^-1 ) delayed fruit ripening and reduced gray mold. Compared with MeSA treatment, 1-MCP (0.5 µL L^-1 ) effectively delayed fruit ripening. Further, MeSA combined with 1-MCP treatment was more effective in inhibiting fungal decay during storage than MeSA treatment alone. The combined treatment not only enhanced pathogenesis-related protein 1 (PR1) expression, activities of defense enzymes and total phenolic content but also inhibited the increase in electrical conductivity and malondialdehyde content. The combined treatment was also more effective in retaining firmness, color change and titratable acidity content than MeSA treatment alone.

CONCLUSION

MeSA combined with 1-MCP treatment was a useful technique to maintain quality and alleviate gray mold in postharvest tomato fruit during storage. © 2018 Society of Chemical Industry.

Synergistic Effects of l-Arginine and Methyl Salicylate on Alleviating Postharvest Disease Caused by Botrysis cinerea in Tomato Fruit

The effects of l-arginine (Arg, 1 mM) and/or methyl salicylate (MeSA, 0.05 mM) treatment on gray mold caused by Botrytis cinerea in tomato fruit were studied. Results indicated that Arg or MeSA alleviated the incidence and severity of fruit disease caused by B. cinerea, and that both Arg and MeSA (Arg + MeSA) further inhibited the development of fruit decay. Treatment with Arg + MeSA not only enhanced the activities of superoxide dismutase, catalase, and peroxidase but also promoted the expression levels of pathogenesis-related protein 1 gene and the activities of defense-related enzymes of phenylalanine ammonia-lyase, polyphenol oxidase, β-1,3-glucanase, and chitinase during most of the storage periods, which were associated with lower disease incidence and disease index. In addition, the combined treatment elevated the levels of total phenolics, polyamines, especially putrescine, and nitric oxide. These observations suggest that treatment of fruit with Arg + MeSA is an effective and promising way to alleviate postharvest decays on a commercial scale.

Efficacy of intravenous immunoglobulin in the treatment of persistent BK viremia and BK virus nephropathy in renal transplant recipients

BK virus-associated nephropathy (BKVN) can cause clinically significant viral infection in renal transplant recipients, leading to allograft dysfunction and loss. The usual management of BKVN involves the reduction of immunosuppression and the addition of leflunomide, quinolones, and cidofovir, but the rate of graft loss remains high. The aim of this study was to assess the impact of treatment with intravenous human immunoglobulin (IVIG) on the outcome of BKVN in renal transplant recipients. Upon diagnosis of BKVN, patients remained on anti-polyomavirus treatment, consisting of the reduction of immunosuppression and the use of leflunomide therapy. Treatment with IVIG was given only to patients who did not respond to 8 weeks of the adjustment of immunosuppression and leflunomide. All 30 patients had persistent BKV viremia and BKVN with their mean BK viral loads higher than the baseline (range, 15,000-2 million copies/mL). Mean peak BK load was 205,314 copies/mL compared with 697 copies/mL after 1 year of follow-up. Twenty-seven patients (90%) had a positive response in clearing viremia. The actuarial patient and graft survival rates after 12 months were 100% and 96.7%, respectively. IVIG administration appeared to be safe and effective in treating BKV viremia and BKVN and preventing graft loss in patients who had inadequate response to immunosuppression reduction and leflunomide therapy.

Downregulation of miR-302c and miR-520c by 1,25(OH)2D3 treatment enhances the susceptibility of tumour cells to natural killer cell-mediated cytotoxicity

Background:

NKG2D recognises several ligands, including polymorphic major histocompatibility complex class I chain-related chain-related proteins A and B (MICA/B) and unique long 16-binding proteins (ULBPs). These ligands are present on cancer cells and are recognised by NKG2D in a cell-structure-sensing manner, triggering natural killer (NK) cell cytotoxicity. However, the mechanisms that control the expression of NKG2D ligands in malignant cells are poorly understood. 1-α,25-Dihydroxyvitamin D3 (1,25(OH)2D3) was recently shown to enhance the susceptibility of melanoma cells to the cytotoxicity of NK cells. However, the function of 1,25(OH)2D3 in other cancers and its potential mechanisms of action remain unknown.

Methods:

The expression levels of miR-302c and miR-520c in Kasumi-1, K562, MCF7 and MDA-MB-231 cells were evaluated using quantitative real-time PCR. The targets of miR-302c and miR-520c were confirmed by luciferase reporter assay. The killing effects of NK92 cells against Kasumi-1, K562, MCF7 and MDA-MB-231 cells were examined using the CytoTox 96 Non-Radioactive Cytotoxicity Assay. The levels of cytokines IFN-γ and granzyme B, which indicate the activation of NK cells, were also measured by enzyme-linked immunosorbent assay.

Results:

Treatment with 1,25(OH)2D3 enhanced the susceptibility of both the haematological tumour cell line Kasumi-1 and solid tumour cell line MDA-MB-231 to NK92 cells. miR-302c and miR-520c expression was induced, and their levels inversely correlated with the levels of NKG2D ligands MICA/B and ULBP2 upon 1,25(OH)2D3 treatment. A luciferase reporter assay revealed that miR-302c and miR-520c directly targeted the 3′-UTRs of MICA/B and ULBP2 and negatively regulated the expression of MIA/B and ULBP2. Moreover, upregulation of miR-302c or miR-520c by transfection of their mimics remarkably reduced the viability of Kasumi-1 cells upon NK cell co-incubation. By contrast, the suppression of the activity of miR-302c or miR-520c by their respective antisense oligonucleotides improved the resistance of Kasumi-1 cells to NK cells.

Conclusion:

1,25(OH)2D3 facilitates the immuno-attack of NK cells against malignant cells partly through downregulation of miR-302c and miR-520c and hence upregulation of the NKG2D ligands MICA/B and ULBP2.

Increased levels of soluble vascular endothelial cadherin are associated with poor outcome in severe sepsis

Endothelial cells are thought to play a key role in sepsis pathogenesis: vascular endothelial damage occurs in severe sepsis and multiple organ dysfunction. Soluble vascular endothelial cadherin (VE-cadherin) levels were investigated in a prospective study involving 28 consecutive critically ill patients with or without severe sepsis who were admitted to surgical intensive care; 13 healthy age-matched volunteers were included as controls. Soluble VE-cadherin levels increased significantly in patients with severe sepsis compared with ill patients without severe sepsis and healthy controls. There was a significant linear correlation between soluble VE-cadherin levels and illness severity scores. Soluble VE-cadherin levels were significantly higher in patients who died compared with survivors. In vitro cell culture showed that serum from patients with severe sepsis greatly decreased VE-cadherin staining at intercellular junctions and total VE-cadherin expression in human umbilical cord vein endothelial cells. These findings suggest that endothelial cells play an important role in the poor outcome of patients with severe sepsis.

Monocyte CD147 is induced by advanced glycation end products and high glucose concentration: possible role in diabetic complications

CD147 is a highly glycosylated transmembrane protein that is known to play a role in regulation of many protein families. It has the unique ability to maintain functional activity in both the membrane bound state and in the soluble form. CD147 is known to play a role in regulation of matrix metalloproteinase (MMP) expression, but whether its expression is affected by the diabetic milieu is not known, and its role in regulation of monocyte MMPs in this environment has not been investigated. Therefore, in this study we investigated the effect of advanced glycation end products (AGEs) and high glucose (HG; 25 mM), on monocyte CD147 expression. Culture of THP-1 monocytes in the presence of AGEs or HG significantly increased CD147 at the gene and protein level. THP-1 cell results were confirmed using freshly isolated monocytes from human volunteers. The effect of AGEs and HG on CD147 expression was also mimicked by addition of proinflammatory cytokines. Addition of AGEs or HG also increased expression of monocyte MMP-1 and MMP-9 but not MMP-2. This increase in MMPs was significantly attenuated by inhibition of CD147 using either a small interfering RNA or an anti-CD147 antibody. Inhibition of NF-κB or addition of antibodies to either TNF-α or the receptor for AGE (RAGE) each significantly prevented in a dose-dependent manner the induction of CD147 gene and protein by AGE and also decreased MMP-1 and MMP-9. This novel result shows that AGEs can induce monocyte CD147 expression, an effect mediated by inflammatory pathways and RAGE. Because MMPs play a role in monocyte migration, inhibition of their regulator CD147 may assist in the prevention of diabetic complications, particularly those where monocyte infiltration is an early initiating event.

Mitochondrial DNA content in peripheral blood monocytes: relationship with age of diabetes onsetand diabetic complications

AIMS/HYPOTHESIS

We examined whether age of type 2 diabetes onset is related to mitochondrial DNA content in peripheral blood monocytes (PBMCs).

METHODS

PBMCs were isolated from 65 patients with type 2 diabetes. To minimise age as a confounder, only patients aged >or=50 years were studied. Sample mitochondrial DNA (mtDNA) content was determined by amplification of the mitochondrial gene CYT-B (also known as MT-CYB) and adjusted for single-copy nuclear control genes (36B4 [also known as RPLPO] and GAPDH).

RESULTS

Age of diabetes onset ranged from 25 to 69 years. There was a significant positive relationship between age of diabetes onset in quartiles and mtDNA content for the whole group (p = 0.02 for trend). When stratified by the presence of diabetes complications, a strong positive relationship was observed between age of diagnosis and mtDNA content for participants without diabetic complications (r = 0.7; p = 0.0002), but not for those with complications (r = -0.04; p = 0.8). Multivariate analysis confirmed age of onset and complication status as independent determinants. There was co-linearity between age of onset and disease duration, with similar relationships also seen between duration and mtDNA content.

CONCLUSIONS/INTERPRETATION

An earlier age of type 2 diabetes onset is associated with a lower PBMC mtDNA content, but only in patients without diabetes complications. This may reflect a differing biology of PBMC mtDNA in those with early-onset diabetes and those who are prone to complications. PBMC mtDNA depletion may accelerate diabetes onset; however the independent effect of diabetes duration remains to be evaluated.

A mutation in the 5' untranslated region of the BRCA1 gene in sporadic breast cancer causes downregulation of translation efficiency

We screened 117 breast tumour samples in Chinese females for mutations in the breast cancer 1 (BRCA1) gene and identified a novel mutation in the 5' untranslated region (5' UTR) in two patients with grade III infiltrating ductal breast carcinoma. We examined whether this 5' UTR mutation affected the translational efficiency of BRCA1 protein. A vector was constructed containing the mutated 5' UTR up-stream of luciferase and we compared its translational efficiency with a wild-type 5' UTR. The expression of BRCA1 protein in breast tumour samples was evaluated using immunohistochemistry. The mutated 5' UTR of BRCA1 resulted in less luciferase activity compared with the wild-type 5' UTR, while there were no significant differences in luciferase mRNA levels. BRCA1 protein was much less expressed in breast tumour tissue from patients with the 5' UTR mutation than in samples from patients without the mutation. Our results show that a mutation in the 5' UTR of the BRCA1 gene downregulates translational efficiency of the protein.

The interaction of metal ions and Marimastat with matrix metalloproteinase 9

The effect of a range of metal ions on the ability of Marimastat to inhibit matrix metalloproteinase 9 (MMP-9) was examined in a fluorescence based proteolytic assay. Whilst none of the metals examined significantly affected the inhibitory ability of Marimastat, several metal ions did have a significant effect on MMP-9 activity itself. In the absence of Marimastat, Zn(II) and Fe(II) significantly inhibited MMP-9 activity at metal ion concentrations of 10 and 100 microM, respectively. In both the absence and presence of Marimastat, Cd(II) significantly inhibited MMP-9 at 100 microM. In contrast, 1 mM Co(II) significantly upregulated MMP-9 proteolytic activity.

First look: what brings clergy candidates into ministry and what happens when they don't get it

This article reports on a retrospective examination of all candidates for ordained ministry in Alabama-West Florida Annual Conference of The United Methodist Church from September 1995 to 1998. The results showed, contrary to expectations, that clergy in this annual conference are significantly more likely than the general population to become physically ill when placed under stress. One of the major stressors identified in this study was the likelihood that the clergy persons will not receive the high levels of affirmation and reinforcement they look for. The author presents some conclusions and suggestions both for action to change the predictions and for further research.

Computed tomography guided core needle biopsy diagnosis of pelvic actinomycosis

BACKGROUND

Pelvic actinomycosis is a chronic suppurative inflammatory disease caused by the anaerobic Gram-positive bacilli Actinomyces israelii. The propensity of this disease to simulate gynecological malignancies has been described previously. The great majority of these patients were diagnosed with actinomycotic diseases during or after exploratory laparotomy, but rarely preoperatively. We reviewed the literature pertaining the management of pelvic actinomycosis.

CASE

A nulliparous woman with a long history of intrauterine contraceptive device (IUD) and recent Papanicolaou smear findings consistent with the presence of actinomyces presented with chronic vague lower abdominal pain, weight loss, poor appetite, and recent increase in abdominal girth associated with a large immobile pelvic mass. Transcutaneous computed tomography guided core needle biopsy established the diagnosis of pelvic actinomycosis obviating immediate surgical intervention. Intravenous and subsequent long-term oral penicillin therapy was constituted and resulted in a significant decrease in the size of the pelvic mass.

CONCLUSION

In patients presenting with pelvic masses and a history of IUD placement, actinomycotic infection should be considered and diagnosis attempted by imaging guided needle biopsy. Furthermore, this case suggested that correct nonsurgical diagnosis of pelvic actinomycosis followed by prolonged antibiotic therapy might eliminate the need for extensive extirpative surgery and assist in maintaining future fertility.

Quantitative characterization of eye tracking dysfunction in schizophrenia

The purpose of this study was to characterize the nature of the processes that are involved in eye tracking dysfunction (ETD). We identified a combination of quantitative measures that best distinguished qualitatively normal eye tracking from qualitatively abnormal eye tracking, using discriminant analysis. Discriminant scores distinguished schizophrenics with ETD from both schizophrenics with normal eye tracking and normal controls, but did not distinguish schizophrenics with normal eye tracking from normal controls, underscoring the heterogeneity of schizophrenic patients with respect to eye tracking. The results of the discriminant analysis indicated that ETD is a multivariate process involving a primary impairment in the smooth pursuit system characterized by increased catch-up saccades and reduced gain, and, secondarily, disinhibition of intrusive saccades, especially square-wave jerks. Quantitative characterization of ETD makes it possible to consider eye tracking as a quantitative trait in genetic investigations of a multidimensional phenotype.

Immunohistochemical localization of phospholipase D1 in rat central nervous system

Phospholipase D (PLD) is one of the intracellular signal transduction enzymes and plays an important role in a variety of cellular functions. We investigated the distribution of PLD isozyme, PLD1 in the rat brain and spinal cord using an immunological approach. Western blot analysis showed the presence of PLD1 protein in all tissues studied, with significantly higher levels in the brainstem and spinal cord, which was correlated with the results obtained from PLD activity assay. Prominent and specific signals of PLD1 were observed in many functionally diverse brain areas, including the olfactory bulb, medial septum-diagonal band complex, cerebral cortex, brainstem, cerebellum, and spinal cord. In the brainstem, the red nucleus, substantia nigra, interpeduncular nucleus, cranial motor nuclei (trigeminal motor, abducent, facial, and hypoglossal), sensory cranial nerve nuclei (spinal trigeminal, vestibular, and cochlear), as well as nuclei of the reticular formation, all showed intense immunoreactivity. Purkinje cells and deep cerebellar nuclei of the cerebellum were also labeled intensely. However, no significant labeling was found in the thalamus, epithalamus, and basal ganglia. Although many of the PLD1 immunoreactive cells were neurons, PLD1 was also expressed in glial cells such as presumed astrocytes and tanycytes. These findings suggest that PLD1 may play an important role in the central nervous system of the adult rat.

Dysregulated production of interferon-gamma, interleukin-4 and interleukin-6 in early tuberculosis patients in response to antigen 85B of Mycobacterium tuberculosis

Both interferon-gamma (IFN-gamma) and interleukin (IL)-4 expression in T cells and IL-6 expression in cells of the monocyte/macrophage lineage were monitored using antigen 85B (Ag85B) protein and purified protein derivative (PPD) antigen in the early stages of tuberculosis (TB). We showed that the levels of cell-associated IFN-gamma and IL-4 (mRNA and intracellular cytokine) in Ag85B-stimulated T cells were significantly depressed in TB patients compared with those in healthy tuberculin reactors. On the other hand, the capacity of peripheral blood mononuclear cells (PBMC) to produce IL-6 spontaneously ex vivo was enhanced in patients (P < 0. 001), but their corresponding capacities to respond to Ag85B were not significantly different from those of normal donors. After 2 months of antituberculosis therapy, the mean blastogenic responses of Ag85B-stimulated PBMC from seven TB patients were increased 6. 1-fold (P = 0.011). Furthermore, the proportions of both IFN-gamma- (P < 0.01) and IL-4- (P = 0.05) producing T cells were significantly increased. However, those of IL-6-producing cells were diminished in response to Ag85B (P = 0.05). Our results suggest that there may be an altered regulation of IFN-gamma, IL-4 and IL-6 to Ag85B in the early stages of TB.

TCR internalization induced by peptide/MHC ligands requires the transmembrane domains of alphabeta chains of TCR, but not the expression of CD8 and Thy-1 molecules

T-cell receptor (TCR) internalization occurs via TCR recognition of the peptide/MHC molecule complex on antigen presenting cell (APC). In this study, the requirements for inducing the internalization of TCR molecules on Ld major histocompatibility complex (MHC) class I-restricted T-cells were investigated with 2C cytotoxic T-lymphocyte (CTL) clones with defined peptides as the antigen. To evaluate the function of the transmembrane region of TCR alphabeta chains in TCR internalization, we generated T-cell transfectants expressing the wild type and glycosylphosphatidyl inositol (GPI)-linked form of 2C TCR. Among all peptides forming proper ligands to 2C TCR, only the Qp2Ca peptide induced TCR internalization, which was known to have the highest affinity to both Ld MHC class I molecules and TCR in association with Ld molecules. Such TCR internalization was not observed in cells expressing the GPI-linked form of 2C TCR. Furthermore, the expression of CD8 coreceptor and Thy-1 accessory molecules were both not required for Qp2Ca-induced TCR internalization, and these molecules did not accompany TCR internalization. Altogether, these results suggest that TCR internalization on CTL is not a prerequisite for CTL function.

Purification and immunoreactivity of three components from the 30/32-kilodalton antigen 85 complex in Mycobacterium tuberculosis

The three proteins of the antigen 85 complex (85A, 85B, and 85C), which are major secretory products of Mycobacterium tuberculosis, were purified to homogeneity in large amounts by a combination of chromatography on hydroxylapatite, DEAE-Sepharose, and DEAE-Sephacel and gel filtration from M. tuberculosis culture filtrate. Then we examined the immunological reactivity of the three proteins in tuberculosis patients and healthy controls. Antibody responses to the 85B and 85A proteins in patients were significantly greater than responses to the 85C protein. In contrast, all three antigens induced significant lymphoproliferation and gamma interferon production in peripheral blood mononuclear cells from healthy tuberculin reactors.

[Chemical constituents of Conyza blinii Lévl]

OBJECTIVE

To study the chemical constituents in the air-dried part of Conyza blinii.

METHOD

The constituent isolation was done by solvent-extraction together with column chromatography. Several methods, such as IR, 1HNMR, 13CNMR and MS, were used to determine the structures of the isolated constituents.

RESULT

Three compounds were isolated from the air-dried part of Conyza blinii and identified as friedelinol, n-triacontanol and daucosterol on the basis of physical and chemical properties and spectroscopic analysis.

CONCLUSION

These compounds have not been discovered previously in this plant.

[Chemical constituents of Rheum wittrochii Lundstr(II)]

OBJECTIVE

To study the chemical constituents in the root of Rheum wittrochii.

METHOD

Chromatography and spectroscopic analysis to isolate and elucidate the chemical constituents in the plant.

RESULT

Six compounds, namely 3, 5-dihydroxy-4'-methoxystilbene; 3, 5, 4'-tridroxystilbene; piceatannol; desoxyrhaponticin; piceatannol-4'-O-beta-D-glucopyranoside; 2, 5-dimethyl-7-hydroxychromone, have been isolated from ethyl ether and ethyl acetate fractions.

CONCLUSION

These compounds were isolated from the title plant for the first time.

[Chemical constituents of Rheum wittrochii Lundstr(I)]

OBJECTIVE

To study the chemical constituents in the root of Rheum wittrochii.

METHOD

Chromatography and spectroscopic analysis were used to isolate and elucidate the chemical constituents in the plant.

RESULT

Six compounds, namely chrysophanol, physcion, emodin, chrysophanol-8-O-beta-D-glucopyranoside, physcion-8-O-beta-D-glucopyranoside and beta-sitosterol, have been isolated from petroleum ether and ethyl acetate fractions.

CONCLUSION

All the above-cited compounds were isolated from the title plant for the first time, and anthraquinone compounds are some of the major constituents of R. wittrochii.

[Chemical constituents of Conyza blinii Lévl]

Five compounds were isolated from the aerial part of Conyza blinii. On the basis of physicochemical properties and spectroscopic analysis, they were identified as alpha-spinasterol, 5, 8-dihydroxy-7, 3', 4'-trimethoxyflavone, caffeic acid, quercetin and syringic acid. All these compounds were isolated from the plant of C. blinii for the first time.

Thought disorder in adolescent-onset schizophrenia

The nature of the thinking disturbances found in adolescent-onset psychotic conditions is not as well-characterized as the thought disorders found in adult psychotic patients. We used the Thought Disorder Index to examine whether schizophrenic patients in whom psychotic symptoms appear in adolescence show the same characteristic features of thought disorder as do adult schizophrenics. Quantitative and qualitative features of thought disorder were assessed in psychiatric inpatients with adolescent-onset schizophrenia, psychotic depression, and nonpsychotic conditions compared with normal control adolescents. Elevated thought disorder occurred in all groups of adolescents hospitalized for an acute episode of psychiatric illness. The magnitude of the elevation and the frequency of occurrence of disordered thinking were greatest in the psychotic adolescents. The qualitative features of the thought disturbances found in the schizophrenic adolescents were distinct from those observed in adolescents with psychotic depression. The thinking of the schizophrenic adolescents resembled that of adult schizophrenics. In both conditions thought disorder is characterized by idiosyncratic word usage, illogical reasoning, perceptual confusion, loss of realistic attunement to the task, and loosely related ideas.

Presence of prostaglandin EP4 receptor gene expression in a rat gastric mucosal cell line

RGM-1 is an epithelial cell line established from gastric mucosa of adult Wistar rats. In this study, we characterized this newly established cell line by Northern blot analysis. We also investigated deoxyribonucleic acid (DNA) synthesis and hexosamine production in RGM-1 by PGE2. Northern blot analysis did not detect any transcript of proton pump, gastrin receptor, histidine decarboxylase, somatostatin and pepsinogen 1, indicating the absence of characteristics of parietal, ECL, D and chief cells in RGM-1 cells. However, this periodic acid-Schiff (PAS)-positive cell line expressed prostaglandin EP4 receptor mRNA but not EP1 and EP3 receptor mRNAs. [3H]-thymidine incorporation into DNA of the cells was not increased by PGE2. In contrast, PGE2 increased hexosamine content in RGM-1 cells. These results suggest that RGM-1 may be a useful model of gastric mucosal cells and that PGE2 plays a role on mucin synthesis in RGM-1 cells possibly via EP4 receptors.