Enhancing tomato disease resistance through endogenous antifungal proteins and introduced nematode-targeting dsRNA of biocontrol agent Bacillus velezensis HS-3

BACKGROUND

As a type of biological control agent (BCA), Bacillus velezensis possesses the efficacy of inhibiting pathogenic microorganisms, promoting plant growth, and overcoming continuous cropping obstacles (CCOs). However, there is limited reporting on the optimization of the cultivation conditions for such biocontrol agents and their role as double-stranded RNA (dsRNA) delivery vectors.

RESULTS

In this study, a Bacillus velezensis strain HS-3 was isolated from the root zone of tomato plants with in vitro anti-Botrytis cinerea activity. The investigation into active compounds revealed that HS-3 predominantly employs proteins with molecular weights greater than 3 kDa for its antifungal activity. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis identified various proteases and chitosanase, further suggesting that HS-3 most likely employs these enzymes to degrade fungal cell walls for its antifungal effect. To optimize the production of extracellular proteins, fermentation parameters for HS-3 were systematically optimized, leading to an optimized medium (OP-M). HS-3 cultured in OP-M demonstrated enhanced capacity to assist tomato plants in withstanding CCOs. However, the presence of excessive nematodes in diseased soil resulted in the disease severity index (DSI) remaining high. An RNA interference mechanism was further introduced to HS-3, targeting the nematode tyrosine phosphatase (TP) gene. Ultimately, HS-3 expressing dsRNA of TP in OP-M effectively assisted tomatoes in mitigating CCOs, reducing DSI to 2.2% and 17.8% of the control after 45 and 90 days of growth, respectively.

CONCLUSION

The advantages of Bacillus velezensis in crop disease management and the mitigation of CCOs become even more pronounced when utilizing both optimized levels of endogenous enzymes and introduced nematode-targeting dsRNA. © 2024 Society of Chemical Industry.

Chloroplast display of subunit vaccines and their efficacy via oral administration

As a safe and natural "capsule," plants have several advantages over mammals and microorganisms for the production of oral vaccines. In this study, we innovatively utilized the transmembrane region of the pea Translocase of chloroplast 34 (TOC34) protein to display two subunit vaccines, capsid protein VP2 of Porcine parvovirus (PPV) and the heat-labile enterotoxin B (LTB) of Escherichia coli, on the surface of chloroplasts. Unlike microbial display techniques, chloroplast display circumvents antigen degradation in the stomach while retaining the size characteristic of microorganisms. Additionally, a co-expressed peptide adjuvant, antimicrobial peptide protegin-1 (PG1), was used to enhance the strength of oral immunization. Immunohistochemistry and trypsin digestion of chloroplast surface proteins confirmed the successful localization of both antigens on the chloroplast surface. In stable transgenic tobacco plants, the expression level of VP2-TOC34 ranged from 0.21 to 6.83 μg/g FW, while LTB-TOC34 ranged from 2.42 to 10.04 μg/g FW. By contrasting the digestive characteristics of plant materials with different particle sizes, it was observed that plant materials with diameters around 1 mm exhibited more prominent advantages in terms of chloroplast release and antigen exposure compared to both larger and smaller particles. Oral immunization resulted in significantly increased levels of specific IgG and secretory IgA in the mice compared to the control, with similar effects observed between the groups receiving oral immunization alone and those receiving a combination of initial injection and subsequent oral immunization. Challenge experiments further demonstrated the effective protection against infection in mice using this approach. These findings highlight the potential of chloroplast display technology for the development of effective oral vaccines.

Identification and Characterization of Two Novel Extracellular β-Glucanases from Chaetomium globosum against Fusarium sporotrichioides

Chaetomium globosum can inhibit the growth of fusarium by means of their extracellular proteins. Two novel β-glucanases, designated Cgglu17A and Cgglu16B, were separated from the supernatant of C. globosum W7 and verified to have the ability to hydrolyze cell walls of Fusarium sporotrichioides MLS-19. Cgglu17A (397 amino acids) was classified as glycoside hydrolase family 17 while Cgglu16B belongs to the family16 (284 amino acids). Recombinant protein Cgglu17A was successfully expressed in Escherichia coli, and the enzymes were purified by affinity chromatography. Maximum activity of Cgglu17A appeared at the pH 5.5 and temperature 50 °C, but Cgglu16B shows the maximum activity at the pH 5.0 and temperature 50 °C. Most of heavy metal ions had inhibition effect on the two enzymes, but Cgglu17A and Cgglu16B were respectively activated by Ba2+ and Mn2+. Cgglu17A exhibited high substrate specificity, almost only catalyzing the cleavage of β-1,3-glycosidic bond, in various polysaccharose, to liberate glucose. However, Cgglu16B showed high catalytic activities to both β-1,3-glycosidic and β-1,3-1,4-glycosidic bonds. Cgglu17A was an exo-glucanase, but Cgglu16B was an endo-glucanase based on hydrolytic properties assay. Both of two enzymes showed potential antifungal activity, and the synergistic effect was observed in the germination experiment of pathogenic fungus. In conclusion, Cgglu17A (exo-1,3-β-glucanase) and Cgglu16B (endo-1,3(4)-β-glucanase) were confirmed to play a key role in the process of C. globosum controlling fusarium and have potential application value on industry and agriculture for the first time.

[Diagnostic values of nuclear score combined with cyclin D1 immunocytochemistry in indeterminate thyroid follicular nodules in preoperative fine needle aspiration]

Objective: To assess the feasibility of nuclear score combined with cyclin D1 immunocytochemistry in classifying indeterminate thyroid nodules with fine-needle aspiration (FNA) cytological diagnosis of Bethesda category Ⅲ-Ⅴ. Methods: A consecutive cohort of 118 thyroid FNA specimens with indeterminate diagnosis (TBSRTC category Ⅲ-Ⅴ) and available histopathologic follow-up data were collected between December 2018 and April 2022 at the Department of Pathology, Beijing Hospital, China. These cases were subjected to cytological evaluation and cyclin D1 immunocytochemistry. The optimal cut-off points of a simplified nuclear score and the percentage of cyclin D1-positive cells for the diagnosis of malignancy or low-risk neoplasm were determined using the receiver operating characteristic (ROC) curves and area under the ROC curve (AUC). The specificity, sensitivity, positive predictive value (PPV) and negative predictive value (NPV) of nuclear score and cyclin D1 immunostaining were evaluated from the crosstabs based on cut-off points. The diagnostic accuracy of simplified nuclear score combined with cyclin D1 immunostaining was estimated using ROC curve analysis. Results: Nuclear grooves, intra-nuclear inclusions and chromatin clearing were more commonly found in malignancy/low-risk neoplasms than benign lesions (P=0.001, P=0.012 and P=0.001 respectively). A cut-off point of≥2 for the simplified nuclear score was sensitive for defining malignancy/low-risk neoplasm, and its PPV, NPV, sensitivity and specificity were 93.6%, 87.5%, 99.0% and 50.0% respectively. A positive cut-off point of 10% positive thyroid cells in cyclin D1 immunostaining demonstrated sensitivity of 88.5%, specificity of 100%, PPV of 100% and NPV of 53.8% for correctly detecting thyroid malignancy or low-risk neoplasm. The sensitivity and PPV of simplified nuclear score combined with cyclin D1 immunostaining were 93.3% and 100%, respectively. Both specificity and NPV were maintained at high levels (100% and 66.7%, respectively). The diagnostic accuracy of simplified nuclear score combined with cyclin D1 immunostaining in detecting thyroid malignancy/low-risk neoplasm was increased to 94.1% compared to using either of them alone. Conclusions: Combing simplified nuclear score and cyclin D1 immunostaining on FNA cytology specimens can increase the diagnostic accuracy in classifying thyroid nodules of indeterminate cytological categories. Thus, this supplementary approach provides a simple, accurate, and convenient diagnostic method for cytopathologists so that may reduce unnecessary thyroidectomies.

Identification and functional characterization of a PDR transporter in Tripterygium wilfordii Hook.f. that mediates the efflux of triptolide

KEY MESSAGE

TwPDR1, a PDR transporter from Tripterygium wilfordii Hook.f., was proved to efflux triptolide and its stability could be enhanced by A1033T mutation. Triptolide, an abietane-type diterpene in Tripterygium wilfordii Hook.f., possesses many pharmacological activities. However, triptolide is in short supply and very expensive because it is present at low amounts in natural plants and lack alternative production methods. Transporter engineering, which increases the extracellular secretion of secondary metabolites in in vitro culture systems, is an effective strategy in metabolic engineering but is rarely reported. In this study, TwPDR1, a pleiotropic drug resistance-type ATP binding cassette transporter, was identified as the best efflux pump candidate for diterpenoids through bioinformatics analysis. TwPDR1 was located in the plasma membrane, highly expressed in adventitious roots, and induced by methyl jasmonate. The triptolide efflux function of TwPDR1 was confirmed by transient expression in tobacco BY-2 cells and by downregulation via RNA interference in the native host. However, the overexpression of TwPDR1 had a limited effect on the secretion of triptolide. As shown by previous studies, a single amino acid mutation might increase the abundance of TwPDR1 by increasing protein stability. We identified the A1033 residue in TwPDR1 by sequence alignment and confirmed that A1033T mutation could increase the expression of TwPDR1 and result in the higher release ratio of triptolide (78.8%) of the mutants than that of control (60.1%). The identification and functional characterization of TwPDR1 will not only provide candidate gene material for the metabolic engineering of triptolide but also guide other transporter engineering researches in the future.

P5386Transplantation of endothelial progenitor cells in the treatment of coronary artery microembolism in rats

Objective

As the impairment of myocardial micro-environments due to coronary micro-embolization (CME) compromises the treatment effect of percutaneous coronary intervention and leads to adverse prognosis, we hypothesized that endothelial progenitor cells (EPCs) transplantation could improve cardiac function in the condition of CME.

Materials and methods

Low- (2×105) and high- (2×106) dose rat bone marrow-derived EPCs were transplanted in a model of CME. To develop a CME model, rats were injected with autologous micro-blood clots into the left ventricle. Echocardiography was examined before and 1, 7, and 28 days after EPC transplantation; serum cTNI, vWF,and cardiac microRNA expression were examined one day after EPCs transplantation. Heart morphology and VEGF, vWF, and bFGF expression were examined one day after EPC transplantation.

Figure 1. Results

Results

After 10 days of culture inductions, BM-EPCs have high purity as confirmed by flow cytometry. Cardiac function reflected by LVEF significantly decreased after CME treatment and rescued by low-dose EPC. Compared to the sham group, cTNI, and vWF serum levels increased significantly after CME treatment and rescued by low-dose EPC and high-dose EPC. Low-dose EPC treatment decreased myocardial necrosis and fibrosis and elevated cardiac expression of VEGF and vWF, while decreasing the cardiac expression of bFGF. Low-dose EPC treatment significantly suppressed cardiac expression of microRNA-19a but significantly enhanced microRNA-21, microRNA-214, and microRNA-486-3p expression. In conclusion, our results indicate that low-dose EPC transplantation may play a pro-angiogenic, anti-fibroblast, anti-fibrosis, and anti-necrosis role and enhance cardiac function in a rat model of CME through a microRNA-related pathway.

Acknowledgement/Funding

Supported by the State Key Laboratory of Low-Dimensional Quantum Physics Open Project Fund (No. KF201608)

Cadmium-induced serotonergic neuron and reproduction damages conferred lethality in the nematode Caenorhabditis elegans

Cadmium is a ubiquitous environmental toxicant. The use of Caenorhabditis elegans as a model for monitoring cadmium exposure has revealed several conserved signaling pathways. However, little is known about the killing process during lethality assay. In the present study, we investigated the effects serotonergic neuronal and reproductive damages on cadmium exposure in C. elegans. We found that sterile hermaphrodites, males and worms that passed reproduction span presented high cadmium resistance compared to those of young adults. The results demonstrated that reproduction process other than reproduction capacity conferred cadmium sensitivity. Cadmium exposure resulted in high ratio bagging phenotype, which was a severe reproductive deficit with embryos hatched internally that could cause worms to die early. The mechanism of bagging formation was ascribed to cadmium-induced egg laying deficiency that led embryos to retain and hatch in uterus. The addition of serotonin and imipramine promoted egg laying and thereby increased cadmium resistance. The results demonstrated that vulval muscles responsible for egg laying were still functional, while the serotonergic hermaphrodite specific neurons might be dysfunctional under cadmium exposure. Cadmium exposure resulted in shrinkage of serotonergic neuronal body and reduced expressions of tryptophan hydroxylase, the key enzyme for serotonin synthesis. The protection of serotonergic neuron through transient thermal preconditioning improved survival rate. In conclusion, our study demonstrated that damages of serotonergic neurons and reproduction conferred to cadmium-induced lethality.

Efficiency and Safety Assurance of Six Fungicides Applied on Postharvest Cabbages Stored in a Natural Environment

Postharvest disease is a major factor in the limited shelf life of many fruits and vegetables, and it is often managed using fungicidal spraying or soaking. In this study, we first tested the efficiency of six common fungicides on postharvest head cabbage ( Brassica oleracea var. capitata) against Botrytis cinerea. Afterward, the elimination abilities of these six fungicides on different layers of cabbage heads were examined, and the effects of the household processes on residue removal were evaluated. Results showed that very low contents of residues reached the inner layers and that peeling the three outmost leaves of cabbage could eliminate most of the investigated fungicides. All six fungicides disappeared during washing, stir-frying, or boiling, among which cyprodinil was the easiest to be eliminated. Furthermore, the combined processes reduced the residues below the limits of quantification for all six investigated fungicides, even after 2 days of spraying.

Preparation of N-doped activated carbons with high CO2 capture performance from microalgae (Chlorococcum sp.)

N-Doped activated carbons with high CO₂ adsorption capacity have been prepared from sugar-rich microalgae (Chlorococcum sp.) feedstock via simple hydrothermal carbonization coupled with KOH activation or NH₃ modification.

Establishment of Tripterygium wilfordii Hook. f. Hairy root culture and optimization of its culture conditions for the production of triptolide and wilforine

In order to solve the shortage of natural Tripterygium wilfordii Hook. f. plant resource for the production of the important secondary metabolites triptolide and wilforine, hairy roots were induced from its root calli by Agrobacterium rhizogenes. Induced hairy roots not only could be maintained and grown well in hormone-free half-strength Murashige and Skoog medium but also could produce sufficient amounts of both triptolide and wilforine. Although hairy roots produced approximately 15% less triptolide than adventitious roots and 10% less wilforine than naturally grown roots, they could grow fast and could be a suitable system for producing both secondary metabolites compared with other tissues. Addition of 50 micrometer methyl jasmonate (MeJA) could slightly affect hairy root growth, but dramatically stimulated the production of both triptolide and wilforine, whereas 50 micrometer salicylic acid had no apparent effect on hairy root growth with slightly stimulatory effects on the production of both secondary metabolites. Addition of precursor nicotinic acid, isoleucine, or aspartic acid at the concentration of 500 micrometer had varying effects on hairy root growth, but none of them had stimulatory effects on triptolide production, and only the former two had slightly beneficial effects on wilforine production. The majority of triptolide produced was secreted into the medium, whereas most of the produced wilforine was retained inside of hairy roots. Our studies provide a promising way to produce triptolide and wilforine in T. wilfordii hairy root cultures combined with MeJA treatment.

Subtypes of major depression: latent class analysis in depressed Han Chinese women

BACKGROUND

Despite substantial research, uncertainty remains about the clinical and etiological heterogeneity of major depression (MD). Can meaningful and valid subtypes be identified and would they be stable cross-culturally?

METHOD

Symptoms at their lifetime worst depressive episode were assessed at structured psychiatric interview in 6008 women of Han Chinese descent, age ⩾ 30 years, with recurrent DSM-IV MD. Latent class analysis (LCA) was performed in Mplus. RESULTS; Using the nine DSM-IV MD symptomatic A criteria, the 14 disaggregated DSM-IV criteria and all independently assessed depressive symptoms (n = 27), the best LCA model identified respectively three, four and six classes. A severe and non-suicidal class was seen in all solutions, as was a mild/moderate subtype. An atypical class emerged once bidirectional neurovegetative symptoms were included. The non-suicidal class demonstrated low levels of worthlessness/guilt and hopelessness. Patterns of co-morbidity, family history, personality, environmental precipitants, recurrence and body mass index (BMI) differed meaningfully across subtypes, with the atypical class standing out as particularly distinct.

CONCLUSIONS

MD is a clinically complex syndrome with several detectable subtypes with distinct clinical and demographic correlates. Three subtypes were most consistently identified in our analyses: severe, atypical and non-suicidal. Severe and atypical MD have been identified in multiple prior studies in samples of European ethnicity. Our non-suicidal subtype, with low levels of guilt and hopelessness, may represent a pathoplastic variant reflecting Chinese cultural influences.

The structure of the symptoms of major depression: exploratory and confirmatory factor analysis in depressed Han Chinese women

BACKGROUND

The symptoms of major depression (MD) are clinically diverse. Do they form coherent factors that might clarify the underlying nature of this important psychiatric syndrome?

METHOD

Symptoms at lifetime worst depressive episode were assessed at structured psychiatric interview in 6008 women of Han Chinese descent, age ⩾30 years with recurrent DSM-IV MD. Exploratory factor analysis (EFA) and confirmatoryfactor analysis (CFA) were performed in Mplus in random split-half samples.

RESULTS

The preliminary EFA results were consistently supported by the findings from CFA. Analyses of the nine DSM-IV MD symptomatic A criteria revealed two factors loading on: (i) general depressive symptoms; and (ii) guilt/suicidal ideation. Examining 14 disaggregated DSM-IV criteria revealed three factors reflecting: (i) weight/appetite disturbance; (ii) general depressive symptoms; and (iii) sleep disturbance. Using all symptoms (n = 27), we identified five factors that reflected: (i) weight/appetite symptoms; (ii) general retarded depressive symptoms; (iii) atypical vegetative symptoms; (iv) suicidality/hopelessness; and (v) symptoms of agitation and anxiety.

CONCLUSIONS

MD is a clinically complex syndrome with several underlying correlated symptom dimensions. In addition to a general depressive symptom factor, a complete picture must include factors reflecting typical/atypical vegetative symptoms, cognitive symptoms (hopelessness/suicidal ideation), and an agitated symptom factor characterized by anxiety, guilt, helplessness and irritability. Prior cross-cultural studies, factor analyses of MD in Western populations and empirical findings in this sample showing risk factor profiles similar to those seen in Western populations suggest that our results are likely to be broadly representative of the human depressive syndrome.

Preservation of islet survival by upregulating α3 integrin signaling: the importance of 3-dimensional islet culture in basement membrane extract

AIM

Islet transplantation is a promising treatment to cure diabetes, but is associated with a high rate of early graft failure. The isolation process leads to the loss of the surrounding extracellular matrix, resulting in eventual islet disintegration and apoptosis. The purpose of this study was to determine the effects on the viability of isolated islets of embedding islets in reconstituted basement membrane extract (BME), which is similar to the normal peri-islet BM composition in vivo.

METHODS

Isolated mouse islets were embedded in BME gel for 24 or 48 hours. Expression of caspase-3, α3, and α5, focal adhesion kinase (FAK), phosphor-FAK, and pancreatic duodenal homeobox factor (PDX)-1 were detected with Western immunoblotting.

RESULTS

Impaired aggregation of single islet cells could only be observed in non-BME medium. Islets embedded in BME gel were partially protected from anoikis showed decreased caspase-3 compared with non-BME islets. We also observed an increase of α3 integrin, FAK protein level, and FAK activity. Furthermore, expression of PDX-1 was preserved at 48 hours, suggesting a positive contribution of BME to β-cell activity.

CONCLUSION

These results indicated that embedding islets in BME can upregulate α3 integrin, which may result in preservation of viability and function of isolated islets.

Inhibition of donor-derived T cells trafficking into target organs by FTY720 during acute graft-versus-host disease in small bowel transplantation

In small bowel transplantation (SBTx), graft-versus-host disease (GVHD) is mediated by donor-derived T cells recognizing host major histocompatibility complex (MHC) alloantigens, and represents an important immunological event influencing life in experimental and clinical situations. We evaluated the possibility that a new sphingosine 1-phosphate receptor agonist, FTY720, could diminish GVHD in a rat SBTx model through traffic alteration of donor-derived T cells in target organs. Heterotopic SBTx was performed using a parent (WF)-into-F(1) (WF x ACI) rat combination. Recipient survival, body weight, histopathology, donor-derived T cell subpopulation and cytokine production were compared with untreated controls. FTY720 inhibited lethality and histopathological changes in target organs when administered at 0.5 mg/kg, possibly due to sequestration of donor-derived T cells in the intestinal graft. FTY720 caused a significant reduction in donor T cell numbers in target organs by promoting these cells to home into donor, but not recipient, secondary lymphoid tissues. FTY720 significantly decreased production of interferon (IFN)-gamma in target organs. These findings indicate that FTY720 effectively reduced recirculation of activated donor-derived T cells and recruitment to target organs in GVHD, and was also associated with down-regulated IFN-gamma production. These properties may offer the potential to treat ongoing GVHD in SBTx.

Dynamic production of hypoxia-inducible factor-1alpha in early transplanted islets

More than half of transplanted beta-cells undergo apoptotic cell death triggered by nonimmunological factors within a few days after transplantation. To investigate the dynamic hypoxic responses in early transplanted islets, syngeneic islets were transplanted under the kidney capsule of balb/c mice. Hypoxia-inducible factor-1alpha (HIF-1alpha) was strongly expressed at post-transplant day (POD) 1, increased on POD 3, and gradually diminished on POD 14. Insulin secretion decreased on POD 3 in association with a significant increase of HIF-1alpha-related beta-cell death, which can be suppressed by short-term hyperbaric oxygen therapy. On POD 7, apoptosis was not further activated by continually produced HIF-1alpha. In contrast, improvement of nerve growth factor and duodenal homeobox factor-1 (PDx-1) production resulted in islet graft recovery and remodeling. In addition, significant activation of vascular endothelial growth factor in islet grafts on POD 7 correlated with development of massive newly formed microvessels, whose maturation is advanced on POD 14 with gradual diminution of HIF-1alpha. We conclude that (1) transplanted islets strongly express HIF-1alpha in association with beta-cell death and decreased insulin production until adequate revascularization is established and (2) early suppression of HIF-1alpha results in less beta-cell death thereby minimizing early graft failure.

Beneficial effects of nerve growth factor on islet transplantation

OBJECTIVE

Development of the Edmonton protocol was a pivotal contribution to clinical islet transplantation (ITx). Persistent limitations to ITx include insufficient supply and posttransplant functional failure of islets. In this study, nerve growth factor (NGF) was used to enhance both cultured and transplanted beta-cell function, thus achieving prolonged graft survival.

METHODS

Fluorescence microscopy with ethidium bromide and SYTO green staining was used to evaluate balb/c mouse islet viability. Islets were syngeneically transplanted under the kidney capsule of recipients with streptozotocin-induced diabetes. Intraperitoneal glucose tolerance was used to test posttransplant function.

RESULTS

Improved viability was found in murine islets cultured for 48 hours in 500 ng/mL NGF (P < .05). A submarginal islet mass (260 islet equivalents/recipient) was used for ITx. The NGF-culture resulted in prolonged islet survival (24.7 days vs 5.5 days without NFG culture, n = 6). Intravenous injection of NGF (6 mug) on the day of transplant and postoperative days (POD) 1 + 2 prolonged islet survival from 4.1 days (no treatment) to 13.2 days (n = 6). Glucose tolerance testing performed at posttransplant day 4 showed improvement at 60 and 120 minutes in recipients treated intravenously with NGF (blood glucose of 95 +/- 15 vs 210 +/- 78 and 57 +/- 6 vs 176 +/- 70 mg/dL, respectively).

CONCLUSION

NGF may improve beta-cell function and result in prolonged survival of both cultured and transplanted islets.

A spin triplet supercurrent through the half-metallic ferromagnet CrO2

In general, conventional superconductivity should not occur in a ferromagnet, though it has been seen in iron under pressure. Moreover, theory predicts that the current is always carried by pairs of electrons in a spin singlet state, so conventional superconductivity decays very rapidly when in contact with a ferromagnet, which normally prohibits the existence of singlet pairs. It has been predicted that this rapid spatial decay would not occur if spin triplet superconductivity could be induced in the ferromagnet. Here we report a Josephson supercurrent through the strong ferromagnet CrO2, from which we infer that it is a spin triplet supercurrent. Our experimental set-up is different from those envisaged in the earlier predictions, but we conclude that the underlying physical explanation for our result is a conversion from spin singlet pairs to spin triplets at the interface. The supercurrent can be switched with the direction of the magnetization, analogous to spin valve transistors, and therefore could enable magnetization-controlled Josephson junctions.

Beneficial effects of pancreas transplantation: regeneration of pancreatic islets in the spontaneously diabetic Torii rat

AIMS

Type 2 diabetes is characterized by a combination of insulin resistance and pancreatic beta-cell dysfunction. Although pancreas transplantation (PTx) is mainly performed in patients with type 1 disease, both clinical and experimental data have demonstrated that PTx improves insulin sensitivity in type 2 diabetic recipients. However, it remains unclear whether PTx has the potential to induce islet neogenesis in a recipient's native pancreas.

METHODS

Nondiabetic 10-week-old and diabetic (defined as blood glucose level >250 mg/dL) 25-week-old (average onset age of diabetes) male spontaneously diabetic Torii (SDT; RT1(a)) rats served as donors and recipients, respectively.

RESULTS

In nontreated control SDT rats, beta-cell mass gradually decreased and blood glucose levels progressively increased (>600 mg/dL after 40 weeks of age). In PTx rats, however, the onset of diabetes was significantly delayed (>47.5 +/- 18.2 [graft age] versus 25.2 +/- 3.9 weeks in control rats). On immunohistochemical staining, insulin-secreting islets were observed in the naive pancreata of 40-week-old recipients with PTx (PTx40w), whereas no islets were found in 40-week-old control SDT rats. Moreover, the islets in the native pancreata of PTx40w recipients were located close to ductal structures, and PDX-1 (pancreatic duodenal homeobox-1)-positive cells were more clearly visible. These results indicate the possibility of beta-cell regeneration in the recipient native pancreas by avoiding glucose toxicity under normoglycemic condition achieved by PTx.

CONCLUSIONS

Pancreas transplantation has beneficial effects on impaired islet, inducing regeneration in the spontaneously diabetic Torii rat.

Reference value of young people's erythrocyte sedimentation rate and altitude

The purpose of this paper is to provide a scientific basis for a unified standard of the reference value of young people's erythrocyte sedimentation rate (ESR) in China. The reference values of healthy young people's ESR were collected according to the Wintrobe method, and the relationship between the reference value of young people's ESR and altitude was tested in this paper. It was found that the reference value of young people's ESR decreases when the altitude gradually increases, and the relationship is significant. The method of mathematical univariate regression analysis was used to deduce two regression equations: Y(1) = 10.92-0.00183X +/-2.59 and Y(2) = 18.58-0.00319X +/-4.37. If the altitude value of a particular area of China is known, the reference value of young people's ESR can be calculated by means of the regression equations. Furthermore, depending on the altitude, China can be divided into three districts: Qingzang, Central and Eastern districts.

The relationship between reference value of old people's erythrocyte sedimentation rate and altitude

In order to provide a scientific basic for a unified standard of the reference value of old people's erythrocyte sedimentation rate (ESR) in China. The reference value of healthy old people's ESR was collected according to the Wintrobe method, the relationship between the reference value of old people's ESR and altitude was tested in this paper. It was found that the reference value of old people's ESR decreases when the altitude gradually increases, the relationship is quite significant. The method of mathematical univariate regression analysis was used to deduce two regression equations: Y1 = 16.38 - 0.00301X +/- 6.53, Y2 = 25.92 - 0.00438X +/- 10.25. If the altitude value of a particular area of China is known, the reference value of old people's ESR can be calculated by means of the regression equations. Furthermore, depending on the altitude, China can be divided into three districts: Qingzang Districts, Central Districts and Eastern Districts.

The relationship between the reference value of erythrocyte sedimentation rate and geographical factors

In order to provide a scientific basis for a unified standard of the reference value of erythrocyte sedimentation rate (ESR) in China, the reference value of healthy people's ESR has been collected. The relationship between the reference value of ESR and geographical factors is examined in this paper. Altitude is the most important factor affecting the reference value of ESR, which decreases with increasing altitude; the relationship is quite significant. The method of stepwise regression analysis was used to deduce two regression equations: Y1 = 12.08 - 0.00222X1 + 0.00114X5 +/- 2.95, Y2 = 18.81 - 0.00323X1 + 0.239X4 +/- 4.70. If the geographical factor value of a particular area in China is known, the reference value of ESR of Chinese people can be calculated by means of the regression equations. Furthermore, the dependence on geographical factors in China can be classified as six districts: Qingzang, Southwest, Northwest, Southeast, North and Northeast.

Dissipative properties and scaling law for a layer of granular material on a vibrating plate

The dissipative properties and scaling law for a layer of vertically vibrated granular materials were investigated by means of a dynamical model of a single sphere colliding completely inelastically with a massive, oscillating plate. A relationship is presented of how the temperature of the layer scales with the acceleration of the plate and the restitution coefficient of the grains. The numerical calculation shows the existence of an "energy well" and a "temperature well," which could be used to explain the existence of a f/2 flat (where f is the external driving frequency) state in an experiment on vibrated granular material.

[Rational range and optimum proportion of energy input in farmland]

There exists a rational range of artificial supplemental energy inputs in fields. In the range, the inputs can improve the yield and the output/input ratio. The rational range of energy input in total energy output is bigger than that in the output/input ratio. It is bigger in low yield fields than high yield fields, which suggests that increasing artificial supplemental energy input can increase the production of low yield fields as same as high yield fields. In the rational range of energy input, there exist high efficient lines in water and fertilizer inputs. The highest efficiency occurs when the rational inputs of water and fertilizer occur in these two lines. There also exist optimum lines of energy and economy input proportions. In the two lines, the proportions of energy and economy output/input of water and fertilizer inputs are the highest, which are the optimum of water and fertilizer inputs. Water and fertilizer may replace each other for equal yields, but would result in a decrease in the output/input ratio.

The relationship between normal erythrocyte sedimentation rate of Chinese young people and geographical factors

In order to provide a scientific basis for the layout of a unified standard of the reference value of Chinese young people's erythrocyte sedimentation rate (ESR), the relationship between the reference values of the Chinese healthy young's ESR and five geographical factors was tested according to the Wintrobe methods. The altitude was found to be the most important factor affecting the reference value of the Chinese young's ESR. The altitude increase correlates with the decrease of the reference value of the young's ESR. The method of stepwise regression analysis was used to deduce two multivariate regression equations. If the geographical index values of a particular area of China are known, the reference value of the young's ESR of this region can be calculated by means of the regression equations. Furthermore, the depending on geographical factors, China can be divided into six districts: Qingzang, Southwest, Northwest, Southeast, North and Northeast District, according to the reference values of the Chinese young's ESR.

Impacts of structural photomodification on the toxicity of environmental contaminants: anthracene photooxidation products

The toxicity of polycyclic aromatic hydrocarbons (PHAs) is known to be enhanced by light via photosensitization reactions (production of active oxygen) and photomodification of the chemicals (e.g., oxidation) to more toxic compounds. Anthracene (ANT) toxicity in particular has been found to increase dramatically following photomodification. The objective of this study was to identify the photooxidation products of ANT and assess the toxicity of selected photoproducts. High performance liquid chromatography (HPLC) analysis of anthracene photooxidation revealed a complex array of oxidation products; prevalent among these were anthraquinone (ATQ) and hydroxy-anthraquinones (hATQs). Eleven of these compounds were tested for toxicity using growth inhibition of the duckweed Lemna gibba L. G-3. All but one of the compounds tested were found to be toxic, and when UV radiation was present in the light source toxicity was generally enhanced. The chemicals were also irradiated under SSR prior to toxicity testing. In about half the cases, the ATQ compounds were rapidly photooxidized and the resultant photoproducts were more toxic than the parent compounds. Interestingly, 2-hydroxyanthraquinone, which was not subject to photooxidation, was the most toxic of the compounds tested. As a light stable compound it presents the risk of a persistent environmental hazard.

Discussion on the relationship between normal hematocrit and geographical factors in China

This paper is written in order to provide a scientific basis for laying out an unified standard of the reference value of hematocrit of Chinese healthy people. It studies the relationship between the reference values of Chinese adults' hematocrit, tested according to the Wintrobe Laws and five geographical factors. It is found that the altitude is the most important factor affecting the reference value of Chinese healthy people's hematocrit. As the altitude gradually increases, the reference value of their hematocrit also increases. By using the method of stepwise regression analysis, two multivariate regression equations are deduced. If the geographical index values in a particular area are known, the reference value of Chinese healthy people's hematocrit in this area can be established by means of the regression equations. Furthermore, according to the dependent relationship of the reference value of Chinese healthy people's hematocrit to geographical factors, China can be divided into six districts: Qingzang, Southwest, Northwest, Southeast, North and Northeast district.

Redox activation of Fos-Jun DNA binding activity is mediated by a DNA repair enzyme

The DNA binding activity of Fos and Jun is regulated in vitro by a post-translational mechanism involving reduction-oxidation. Redox regulation occurs through a conserved cysteine residue located in the DNA binding domain of Fos and Jun. Reduction of this residue by chemical reducing agents or by a ubiquitous nuclear redox factor (Ref-1) recently purified from Hela cells, stimulates AP-1 DNA binding activity in vitro, whereas oxidation or chemical modification of the cysteine has an inhibitory effect on DNA binding activity. Here we demonstrate that the protein product of the ref-1 gene stimulates the DNA binding activity of Fos-Jun heterodimers, Jun-Jun homodimers and Hela cell AP-1 proteins as well as that of several other transcription factors including NF-kappa B, Myb and members of the ATF/CREB family. Furthermore, immunodepletion analysis indicates that Ref-1 is the major AP-1 redox activity in Hela nuclear extracts. Interestingly, Ref-1 is a bifunctional protein; it also possesses an apurinic/apyrimidinic (AP) endonuclease DNA repair activity. However, the redox and DNA repair activities of Ref-1 can, in part, be distinguished biochemically. This study suggests a novel link between transcription factor regulation, oxidative signalling and DNA repair processes in higher eukaryotes.