The Arabidopsis A4 subfamily of lectin receptor kinases negatively regulates abscisic acid response in seed germination

Abscisic acid (ABA) is an important plant hormone for a wide array of growth and developmental processes and stress responses, but the mechanism of ABA signal perception on the plasma membrane remains to be dissected. A previous GeneChip analysis revealed that a member of the A4 subfamily of lectin receptor kinases (LecRKs) of Arabidopsis (Arabidopsis thaliana), At5g01540 (designated LecRKA4.1), is up-regulated in response to a low dose of ABA in the rop10-1 background. Here, we present functional evidence to support its role in ABA response. LecRKA4.1 is expressed in seeds and leaves but not in roots, and the protein is localized to the plasma membrane. A T-DNA knockout mutant, lecrka4.1-1, slightly enhanced ABA inhibition of seed germination. Interestingly, LecRKA4.1 is adjacent to two other members of the A4 subfamily of LecRK genes, At5g01550 (LecRKA4.2) and At5g01560 (LecRKA4.3). We found that loss-of-function mutants of LecRKA4.2 and LecRKA4.3 exhibited similarly weak enhancement of ABA response in seed germination inhibition. Furthermore, LecRKA4.2 suppression by RNA interference in lecrka4.1-1 showed stronger ABA inhibition of seed germination than lecrka4.1-1, while the response to gibberellic acid was not affected in lecrka4.1-1 and lecrka4.1-1; LecRKA4.2 (RNAi) lines. Expression studies, together with network-based analysis, suggest that LecRKA4.1 and LecRKA4.2 regulate some of the ABA-responsive genes. Taken together, our results demonstrate that the A4 subfamily of LecRKs has a redundant function in the negative regulation of ABA response in seed germination.

Different biological properties of circulating and bone marrow endothelial progenitor cells in acute myocardial infarction rats

BACKGROUND

Many studies have shown that endothelial progenitor cell (EPC) can enhance the neovascularization of the ischemic myocardium. Peripheral blood and bone marrow are the most convenient resources for EPC.

OBJECTIVE

The aim of the study was to investigate, in vitro and in vivo, the different biological properties between circulating EPC (CEPC) and bone marrow EPC (BM-EPC) of AMI rats.

METHODS

The proliferative, migrative, adherent and angiogenic properties were investigated in vitro. 1 x 10 (6) CEPCs, 1 x 10 (6) BM-EPCs and medium (EBM-2) were injected in the myocardium of AMI rats. Echocardiography, regional myocardial blood flow (RMBF), capillary density and Y chromosome fluorescence in situ hybridization (FISH) were performed at 4 weeks after transplantation.

RESULTS

The CEPCs had higher proliferative, migrative, adherent capabilities and lower senescent ratio, could adhere more quickly to fibronectin than BM-EPCs. CEPCs could form capillary-like structures whereas BM-EPCs did not show similar structures on Matrigel. in vivo, transplanted CEPCs and BM-EPCs were found in cardiac tissue by FISH. CEPCs treatment led to a better cardiac function, RMBF and capillary density than BM-EPCs.

CONCLUSION

Different biological properties were observed between CEPCs and BM-EPCs. Autologous CEPCs are more suitable for the AMI rat.

The OSU1/QUA2/TSD2-encoded putative methyltransferase is a critical modulator of carbon and nitrogen nutrient balance response in Arabidopsis

The balance between carbon (C) and nitrogen (N) nutrients must be tightly coordinated so that cells can optimize their opportunity for metabolism, growth and development. However, the C and N nutrient balance perception and signaling mechanism remains poorly understood. Here, we report the isolation and characterization of two allelic oversensitive to sugar 1 mutants (osu1-1, osu1-2) in Arabidopsis thaliana. Using the cotyledon anthocyanin accumulation and root growth inhibition assays, we show that the osu1 mutants are more sensitive than wild-type to both of the imbalanced C/N conditions, high C/low N and low C/high N. However, under the balanced C/N conditions (low C/low N or high C/high N), the osu1 mutants have similar anthocyanin levels and root lengths as wild-type. Consistently, the genes encoding two MYB transcription factors (MYB75 and MYB90) and an Asn synthetase isoform (ASN1) are strongly up-regulated by the OSU1 mutation in response to high C/low N and low C/high N, respectively. Furthermore, the enhanced sensitivity of osu1-1 to high C/low N with respect to anthocyanin accumulation but not root growth inhibition can be suppressed by co-suppression of MYB75, indicating that MYB75 acts downstream of OSU1 in the high C/low N imbalance response. Map-based cloning reveals that OSU1 encodes a member of a large family of putative methyltransferases and is allelic to the recently reported QUA2/TSD2 locus identified in genetic screens for cell-adhesion-defective mutants. Accumulation of OSU1/QUA2/TSD2 transcript was not regulated by C and N balance, but the OSU1 promoter was slightly more active in the vascular system. Taken together, our results show that the OSU1/QUA2/TSD2-encoded putative methyltransferase is required for normal C/N nutrient balance response in plants.

Transcriptome analysis reveals specific modulation of abscisic acid signaling by ROP10 small GTPase in Arabidopsis

Abscisic acid (ABA) is a hormone that modulates a variety of agronomically important growth and developmental processes and various stresses responses, but its signal transduction pathways remain poorly understood. ROP10, a member of ROP small GTPases in Arabidopsis (Arabidopsis thaliana), is a plasma membrane-associated protein specifically involved in negative regulation of ABA responses. To dissect the ROP10-mediated ABA signaling, we carried out transcriptome analysis using the Arabidopsis full-genome chip. Our analysis revealed a total of 262 and 125 genes that were, respectively, up- and down-regulated (> or =2-fold cutoff) by 1 mum ABA in wild type (Wassilewskija [Ws]); 42 up-regulated and 38 down-regulated genes have not been identified in other studies. Consistent with the nonpleiotropic phenotypes of rop10-1, only three genes were altered in rop10-1 in the absence of ABA treatment. In response to 1 microm ABA, 341 and 127 genes were, respectively, activated and repressed in rop10-1. Interestingly, a particular subset of 21 genes that were not altered by 1 microm ABA in Ws but only activated in rop10-1 was identified. Reverse transcription-polymerase chain reaction analysis revealed the existence of three distinct categories of ABA dose-response patterns. One novel category is characterized by their ABA unresponsiveness in Ws and activation in rop10-1 at 1 microm but not 10 and 100 microm of ABA. This indicates that ROP10 gates the expression of genes that are specific to low concentrations of ABA. Furthermore, almost all of these 21 genes are known to be highly induced by various biotic and abiotic stresses. Consequently, we found that rop10-1 enhanced the sensitivity of seed germination inhibition to mannitol and sodium chloride. Our results suggest that ROP10 negatively regulates ABA responses by specifically and differentially modulating the ABA sensitivity of a subset of genes including protein kinases and zinc-finger family proteins.

Manipulating mouse telomeres: models of tumorigenesis and aging

Telomeres are capping structures at the ends of chromosomes, composed of a repetitive DNA sequence and associated proteins. Both a minimal length of telomeric repeats and telomere-associated binding proteins are necessary for proper telomere function. Functional telomeres are essential for maintaining the integrity and stability of eukaryotic genomes. The capping structure enables cells to distinguish chromosome ends from double strand breaks (DSBs) in the genome. Uncapped chromosome ends are at great risk for degradation, recombination, or chromosome fusion by cellular DNA repair systems. Dysfunctional telomeres have been proposed to contribute to tumorigenesis and some aging phenotypes. The analysis of mice deficient in telomerase activity and other telomere-associated proteins has allowed the roles of dysfunctional telomeres in tumorigenesis and aging to be directly tested. Here we will focus on the analysis of different mouse models disrupted for proteins that are important for telomere functions and discuss known and proposed consequences of telomere dysfunction in tumorigenesis and aging.

Discovery of novel p-arylthio cinnamides as antagonists of leukocyte function-associated antigen-1/intercellular adhesion molecule-1 interaction. 4. Structure-activity relationship of substituents on the benzene ring of the cinnamide

We have shown that p-arylthio cinnamides can inhibit the interaction of LFA-1 and ICAM-1, which is involved in cell adhesion and the inflammatory process. We now show that 2,3-disubstitution on the aryl portion of the cinnamide results in enhanced activity over mono substitution on the ring. The best 2,3-substituents were chlorine and trifluoromethyl groups. Compounds 39 and 40 which contain two CF3 groups have IC(50) values of 0.5 and 0.1 nM, respectively, in inhibiting JY8 cells expressing LFA-1 on their surface, from adhering to ICAM-1. The structure-activity relationship (SAR) was examined using an NMR based model of the LFA-1 I domain/compound 31 complex. One of our compounds (38) was able to reduce cell migration in two different in vivo experiments.

Discovery of potent antagonists of leukocyte function-associated antigen-1/intercellular adhesion molecule-1 interaction. 3. Amide (C-ring) structure-activity relationship and improvement of overall properties of arylthio cinnamides

The interaction of LFA-1 and ICAM-1 plays an important role in the cell adhesion process. On the basis of previously reported SAR and structural information on the binding of our p-arylthiocinnamide series to LFA-1, we have identified the cyclic amide (C-ring) as a site for modification. Improvement in potency and, more importantly, in the physical properties and pharmacokinetic profiles of the leading compounds resulted from this modification. One of the best compounds (11f) is also shown to reduce myocardial infarct size in rat.

Acid, nonacid, and gas reflux in patients with gastroesophageal reflux disease during ambulatory 24-hour pH-impedance recordings

BACKGROUND & AIMS

Gastroesophageal reflux can be acid, nonacid, pure liquid, or a mixture of gas and liquid. We investigated the prevalence of acid and nonacid reflux and the air-liquid composition of the refluxate in ambulant healthy subjects and patients with reflux disease (GERD).

METHODS

Twenty-four-hour ambulatory recordings were performed in 30 patients with symptomatic GERD and erosive esophagitis and in 28 controls. Esophageal pH and impedance were used to identify acid reflux (pH drop below 4.0), minor acid reflux (pH drop above 4.0), nonacid reflux (pH drop less than 1 unit + liquid reflux in impedance), and gas reflux.

RESULTS

The total rate of gastroesophageal reflux episodes was similar in patients and controls. Patients with GERD had a higher proportion (45% vs. 33%) and rate of acid reflux than controls (21.5 [9-35]/24 h vs. 13 [6.5-21]/24 h; P < 0.05). One third of reflux events was nonacid in both groups. Mixed reflux of gas and liquid was the most frequent pattern with gas preceding liquid in 50%-80% of cases. Pure liquid reflux was more often acid in patients with GERD than controls (45% vs. 32%; P < 0.05).

CONCLUSIONS

Reflux of gastric contents was similarly frequent in patients with GERD and controls. Although there was no difference in the overall number of reflux episodes, more acidic reflux occurred in symptomatic patients with GERD, suggesting differences in gastric acid secretion or distribution.

Temperature sensing and cold acclimation

The fundamental question in cold acclimation is how do plants perceive the low but nonfreezing temperatures that activate cold acclimation responses. New findings in the past year suggest that changes in membrane fluidity, cytoskeleton rearrangement, and calcium influxes are among the earliest events taking place in plants upon exposure to low nonfreezing temperatures. In the cyanobacterium Synechocystis PCC6803, temperature change is detected by at least two separate sensors. One of these measures membrane fluidity using a classical two-component system involving histidine kinases and a response regulator in a His-to-Asp phosphorelay. Although these Synechocystis results may not be directly relevant to cold acclimation, they can guide our thinking as we search for biological thermometers in higher plants.

A novel imprinted gene, KCNQ1DN, within the WT2 critical region of human chromosome 11p15.5 and its reduced expression in Wilms' tumors

WT2 is defined by a maternal-specific loss of heterozygosity on human chromosome 11p15.5 in Wilms' and other embryonal tumors. Therefore, the imprinted genes in this region are candidates for involvement in Wilms' tumorigenesis. We now report a novel imprinted gene, KCNQ1DN (KCNQ1 downstream neighbor). This gene is located between p57(KIP2) and KvLQT1 (KCNQ1) of 11p15.5 within the WT2 critical region. KCNQ1DN is imprinted and expressed from the maternal allele. We examined the expression of KCNQ1DN in Wilms' tumors. Seven of eighteen (39%) samples showed no expression. In contrast, other maternal imprinted genes in this region, including p57(KIP2), IMPT1, and IPL exhibited almost normal expression in these samples, although some samples expressed IGF2 biallelically. These results suggest that KCNQ1DN existing far from the H19/IGF2 region may play some role in Wilms' tumorigenesis along with IGF2.

Sequence-based structural features between Kvlqt1 and Tapa1 on mouse chromosome 7F4/F5 corresponding to the Beckwith-Wiedemann syndrome region on human 11p15.5: long-stretches of unusually well conserved intronic sequences of kvlqt1 between mouse and human

Mouse chromosome 7F4/F5 is a syntenic locus of human 11p15.5 in which many imprinted genes are clustered. Transmission of aberrant human 11p15.5 or duplicated 11p causes Beckwith-Wiedemann syndrome (BWS) depending on which parent the chromosome is derived from. To analyze a syntenic mouse locus corresponding to human 11p15.5, mouse BAC contigs were constructed between Nap2 and Tapa1, in which 390 kb was sequenced between Kvlqt1 and Tapa1. An unexpected finding was that of highly conserved intronic sequences of Kvlqt1 between mouse and human, and their homologies came up to at least 160 kb because the length of this gene extended to 350 kb, suggesting the possibility of some functional constraint due to transcriptional and/or post-transcriptional regulation of this region. Many expressed sequence tags (ESTs) were mapped on this locus. Three genes, Lit1 (Kvlqt1-AS), Mtr1 and Tssc4, were identified and characterized. Lit1 is an antisense-transcript of Kvlqt1 and paternally expressed and maternally methylated throughout the developmental stage. The position where Lit1 exists corresponded to a highly conserved region between mouse and human. This transcript extends at least 60 kb from downstream to upstream of exon 10 in Kvlqt1. Tssc4 and Mtr1 carried putative open reading frames but neither was imprinted. Further characterization of this locus based on the sequence comparison between mouse and human will contribute valuable information towards resolving the mechanism of the occurrence of BWS and the associated childhood tumor.

Superantigens augment antigen-specific Th1 responses by inducing IL-12 production in macrophages

Superantigens (SAg) are microbial proteins that mediate antigen-presenting cell (APC)-T cell interaction by cross-linking MHC class II molecules with subsets of TcRVbeta. SAgs are implicated in the pathogenesis of several infectious, inflammatory, and autoimmune diseases. In this study, we examined the influence of SEB on interleukin-12 (IL-12) production and the activation of antigen-specific Th1 responses. Addition of SEB augmented the antigen-induced proliferation of HS-17, a murine MBPp91-103 peptide-specific TcRVbeta6+ CD4+ Th1 clone. SEB augments HS-17 T cell proliferation through its interaction with IA(S) molecules on macrophages, but not with the TcRVbeta6 on HS-17 cells. On binding to IA(S), SEB induces IL-12 production in macrophages, which in turn augments antigen-induced proliferation of HS-17 T cells. Treatment with anti-IA(S) nmAb 10-3.6 inhibited the antigen- and SEB-induced IL-12 production and T cell proliferation. These results suggest that SAgs augment antigen-specific T cell responses by inducing IL-12 production in macrophages.

Development and identification of wheat-Ag.pulcherrimum addition line and substitution line with BYDV resistance

Breeding materials derived from CPI113500, amphidiploid of T. turgidum x Ag.pulcherrimum with barley yellow dwarf virus (BYDV) resistance, were evaluated by using BYDV resistance test, morphology observation, cytogenetics analysis, aneuploid analysis, isozyme electrophoresis, in situ hybridization. Two new germplasms resistant to BYDV were obtained. They were T.aestivum-Ag. pulcherrimum disomic addition line 96S16-11, and T. aestivum-Ag. pulcherrimum disomic substitution line 96W14-9.

Discovery of non-peptidic P2-P3 butanediamide renin inhibitors with high oral efficacy

A new series of non-peptidic renin inhibitors having a 2-substituted butanediamide moiety at the P2 and P3 positions has been identified. The optimized inhibitors have IC50 values of 0.8 to 1.4 nM and 2.5 to 7.6 nM in plasma renin assays at pH 6.0 and 7.4, respectively. When evaluated in the normotensive cynomolgus monkey model, two of the most potent inhibitors were orally active at a dose as low as 3 mg/kg. These potent renin inhibitors are characterized by oral bioavailabilities of 40 and 89% in the cynomolgus monkey. Inhibitor 3z (BILA 2157 BS) was selected as candidate for pre-development.

Vasoactive intestinal peptide inhibits IL-12 and nitric oxide production in murine macrophages

Vasoactive intestinal peptide (VIP) is a naturally occurring neuropeptide widely distributed in the nervous system. In this study, we investigated the effect of VIP on IL-12, TNF alpha and nitric oxide (NO) production in macrophages following activation with lipopolysaccharide (LPS) or superantigens. In vitro studies show that at physiologic concentrations, VIP inhibited IL-12 and NO but not TNF alpha production in macrophages which were stimulated with LPS or superantigens. The inhibitory effect of VIP on IL-12 production appeared to be cAMP mediated since other cAMP inducing agents were also potent in inhibiting IL-12 production. Since IL-12 plays a critical role in T cell function, we suggest that naturally occurring neural hormones can regulate the type and direction of the immune response.

Eskimo1 mutants of Arabidopsis are constitutively freezing-tolerant

Temperate plants develop a greater ability to withstand freezing in response to a period of low but nonfreezing temperatures through a complex, adaptive process of cold acclimation. Very little is known about the signaling processes by which plants perceive the low temperature stimulus and transduce it into the nucleus to activate genes needed for increased freezing tolerance. To help understand the signaling processes, we have isolated mutants of Arabidopsis that are constitutively freezing-tolerant in the absence of cold acclimation. Freezing tolerance of wild-type Arabidopsis was increased from -5.5 degreesC to -12.6 degreesC by cold acclimation whereas the freezing tolerance of 26 mutant lines ranged from -6.8 degreesC to -10.6 degreesC in the absence of acclimation. Plants with mutations at the eskimo1 (esk1) locus accumulated high levels of proline, a compatible osmolyte, but did not exhibit constitutively increased expression of several cold-regulated genes involved in freezing tolerance. RNA gel blot analysis suggested that proline accumulation in esk1 plants was mediated by regulation of transcript levels of genes involved in proline synthesis and degradation. The characterization of esk1 mutants and results from other mutants suggest that distinct signaling pathways activate different aspects of cold acclimation and that activation of one pathway can result in considerable freezing tolerance without activation of other pathways.

New p57KIP2 mutations in Beckwith-Wiedemann syndrome

Beckwith-Wiedemann syndrome (BWS) is characterized by numerous growth abnormalities and an increased risk of childhood tumors. The gene for BWS is localized in the 11p15.5 region, as determined by linkage analysis of autosomal dominant pedigrees. The increased maternal transmission pattern seen in the autosomal dominant-type pedigrees and the findings of paternal uniparental disomy reported for a subgroup of patients indicate that the gene for BWS is imprinted. Previously, we found p57KIP2, which is a Cdk-kinase inhibitor located at 11p15, is mutated in two BWS patients. Here, we screened for the mutation of the gene in 15 BWS patients.

Effect of vasoactive intestinal peptide (VIP) on cytokine production and expression of VIP receptors in thymocyte subsets

Intrathymic T cell precursors undergo a programmed sequence of developmental changes resulting in the production of mature, self-MHC restricted, single positive T lymphocytes which migrate to the periphery. The intrathymic T cell development is controlled by various factors, including cytokines and possibly neuroendocrine hormones. Our previous studies indicate that vasoactive intestinal peptide (VIP) inhibits IL-2 and IL-4 production in thymocytes through different molecular mechanisms. Thymocytes acquire the competence to express IL-2 and IL-2R during thymic development in a maturation-dependent manner. In this study we investigate the effect of VIP on IL-2 production, and the expression of VIP-R1 and VIP-R2 mRNA in different thymocyte subsets in comparison to T cell lines. All thymocyte subsets and T cell lines tested express VIP-R2. In contrast, only single positive, CD4+8- and CD4-8+ thymocytes express VIP-R1. VIP inhibits IL-2 production in CD4+8+ and single positive CD4+8- and CD4-8+ thymocytes and in TH1 cells stimulated through the TCR. No inhibition is observed in CD3-4-8- and single positive CD4+8- and CD4-8+ thymocytes, or in TH1 cells stimulated by a combination of calcium ionophores and phorbol esters. These findings suggest that VIP inhibits IL-2 production through VIP-R2, and that it interferes with a TCR-connected transduction pathway. We also investigate the expression of VIP mRNA in thymocyte subsets and T cell lines, and conclude that thymocytes as well as antigen-specific T cells may function as VIP sources within the lymphoid organs.

Overexpression of the FAD3 desaturase gene in a mutant of Arabidopsis

A mutant of Arabidopsis contained increased levels of 18:3 fatty acids and correspondingly decreased levels of 18:2. The fatty acid phenotype was strongly expressed in root and seed tissues and this observation, together with other data, suggested that the mutation leads to increased activity of the endoplasmic reticulum 18:2 desaturase encoded by the FAD3 gene. Gel-blot analysis of RNA from wild-type and mutant plants established that FAD3 transcript levels were increased 80% in the mutant relative to the wild type. Genetic analysis demonstrated a linkage between the new mutation and the fad3 locus. Linkage of the mutation to fad3 raises the possibility that the lesion is an alteration to the promoter or another regulatory region of the FAD3 gene, which results in increased transcription.

Vasoactive intestinal peptide stimulates p59fyn kinase activity in murine thymocytes

The neuropeptide VIP has immunomodulatory properties, including the inhibition of cytokine production (IL-2, IL-4, and IL-10) in T lymphocytes stimulated through their TCR. The transduction pathways involved in the inhibitory effect of VIP on IL-2 expression are not known. Here we investigate the effect of VIP on the T-cell-specific protein tyrosine kinases p56lck and p59fyn in resting and stimulated thymocytes. VIP does not affect lck or fyn activity in stimulated thymocytes and does not alter the general pattern of cellular tyrosine phosphorylation. However, VIP stimulates p59fyn, but not p56lck, kinase activity in resting thymocytes. The effect is dose dependent, exhibits a specific time course, and is reproduced by other cAMP-inducing agents such as forskolin, prostaglandin E2, and 8-bromo-cAMP, suggesting that cAMP may function as the intracellular mediator.

Down-regulation of cytokine expression in murine lymphocytes by PACAP and VIP

Neuropeptides, such as VIP and PACAP, released or produced in the microenvironment of the primary and secondary lymphoid organs, could affect a variety of immune responses through the regulation of cytokine expression. VIP has been previously shown to inhibit IL-2, IL-4, and IL-10 production in murine lymphocytes stimulated through the TCR-associated CD3 complex. This study shows that, similar to VIP, PACAP-38 inhibits IL-2 production in T lymphocytes. Comparisons with forskolin, a known cAMP inducer, suggest that the increase in intracellular cAMP represents at least one of the transduction pathways involved in IL-2 inhibition, especially in the higher range of neuropeptide concentration. Studies of the detailed molecular mechanisms involved in the regulation of IL-2 expression indicate that reduction of de novo transcription and destabilization of the message contribute to the reduction of steady-state IL-2 mRNA levels following VIP treatment. Examination of several IL-2 transcriptional factors indicates that only NFAT is down-regulated by VIP. Neuropeptides, such as VIP and PACAP, which specifically modulate the expression of various cytokines, could play an important role in the intricate cytokine network controlling local immune responses.

Vasoactive intestinal peptide inhibits IL-4 production in murine T cells by a post-transcriptional mechanism

Vasoactive intestinal peptide (VIP), a neuropeptide present in the peptidergic innervation of lymphoid organs and expressed in thymocytes and peripheral lymphocytes, modulates cytokine expression in T lymphocytes. VIP down-regulates the expression of IL-2 and IL-10 mRNA in T cells stimulated through the TCR-associated CD3 complex. In contrast, IL-4 production is inhibited at a post-transcriptional level. In this study, we investigate the molecular mechanisms involved in the inhibition of IL-4 production by VIP. At the protein level, the time courses for IL-2 and IL-4 inhibition by VIP are different, with IL-4 being affected approximately 24 h later than IL-2. Northern blots and competitive reverse-transcription PCR analysis confirm the post-transcriptional inhibition of IL-4 production in both murine spleen cells and thymocytes activated through the CD3 complex. VIP does not affect IL-4 secretion, and does not induce a rapid IL-4 reuptake. Exogenous rIL-2 completely reverses the inhibitory effect of VIP, suggesting that VIP inhibits IL-4 production indirectly as a consequence of IL-2 inhibition. Studies regarding the newly synthesized IL-4 protein show that although VIP and exogenous IL-2 do not affect the rate of IL-4 synthesis, VIP reduces significantly the stability of the newly synthesized IL-4 protein, and exogenous IL-2 can restore it to the levels observed in activated cells in the absence of VIP. These results explore the molecular mechanisms involved in the neuroendocrine regulation of cytokine production, and support the idea that neuropeptides released or produced in the local lymphoid microenvironment may participate in the intricate cytokine network controlling local immune responses.

Vasoactive intestinal peptide inhibits IL-4 production in murine T cells by a post-transcriptional mechanism

Vasoactive intestinal peptide (VIP), a neuropeptide present in the peptidergic innervation of lymphoid organs and expressed in thymocytes and peripheral lymphocytes, modulates cytokine expression in T lymphocytes. VIP down-regulates the expression of IL-2 and IL-10 mRNA in T cells stimulated through the TCR-associated CD3 complex. In contrast, IL-4 production is inhibited at a post-transcriptional level. In this study, we investigate the molecular mechanisms involved in the inhibition of IL-4 production by VIP. At the protein level, the time courses for IL-2 and IL-4 inhibition by VIP are different, with IL-4 being affected approximately 24 h later than IL-2. Northern blots and competitive reverse-transcription PCR analysis confirm the post-transcriptional inhibition of IL-4 production in both murine spleen cells and thymocytes activated through the CD3 complex. VIP does not affect IL-4 secretion, and does not induce a rapid IL-4 reuptake. Exogenous rIL-2 completely reverses the inhibitory effect of VIP, suggesting that VIP inhibits IL-4 production indirectly as a consequence of IL-2 inhibition. Studies regarding the newly synthesized IL-4 protein show that although VIP and exogenous IL-2 do not affect the rate of IL-4 synthesis, VIP reduces significantly the stability of the newly synthesized IL-4 protein, and exogenous IL-2 can restore it to the levels observed in activated cells in the absence of VIP. These results explore the molecular mechanisms involved in the neuroendocrine regulation of cytokine production, and support the idea that neuropeptides released or produced in the local lymphoid microenvironment may participate in the intricate cytokine network controlling local immune responses.

[Treatment of maxillofacial vascular malformation by arterial embolism and application of sclerosing agent]

30 cases of large cavernous and racemose hemangioma of the maxillofacial were treated selectively with arterial embolism of the tumor and inject Xiaozhiling into the tumor, from November 1990 to November 1993. This method has exact effect either to racemose or to cavernous hemangioma, without facial defect and functional damage. All the patients were followed up 6 months to 3 years. 27 cases were cured, 1 failed, 1 gave up treatment, 1 died of complication. Its mechanism, indications, prevention of complications and recurrence were discussed.

Vasoactive intestinal peptide inhibits interleukin (IL)-2 and IL-4 production in murine thymocytes activated via the TCR/CD3 complex

During their development in the thymus, T cells acquire interleukin (IL)-2 and IL-4 inducibility in a developmentally controlled manner. Although the role of IL-2 and IL-4 in T cell development is still unclear, several reports indicated that IL-2/IL-2R and IL-4/IL-4R interactions in the thymus could play an important role in T cell development. The presence of vasoactive intestinal peptide (VIP)-immunoreactive cells and nerve fibers in the thymus suggests the possible local release of the neuropeptide in the thymic microenvironment. VIP has been previously reported to inhibit IL-2 and IL-4 production, as well as the proliferation of mitogen- or antigen-stimulated peripheral T cells. Here we report on the effect of VIP on IL-2 and IL-4 production by and proliferation of murine thymocytes stimulated through the TCR/CD3 receptor. VIP inhibited both IL-2 and IL-4 production, as well as the proliferation of murine thymocytes in a dose-dependent and specific manner. Structurally related peptides such as secretin or glucagon had little or no inhibitory activity. The intact VIP molecule was required for the inhibitory effect, since amino- or carboxy-terminal fragments did not inhibit IL-2 production. The inhibitory effect of VIP was observed for VIP additions up to 12 h after the initiation of the cultures, and incubations longer than 3 h were required for maximum inhibitory effects. Through its downregulatory effect on IL-2 and IL-4 production, locally released VIP could potentially affect T cell development within the thymus.

Gibberellin-induced changes in the translatable mRNA populations of stamens and shoots of gibberellin-deficient tomato

The gib1 mutant of tomato (Lycopersicon esculentum Mill.) is deficient in endogenous gibberellins and exhibits phenotypes including extreme dwarfism, reduced germination, and abnormal flower development, which are reversed by the application of gibberellic acid (GA3). Previous work has demonstrated that, in stamens of the gib1 mutant, pollen mother-cell development arrests at the premeiotic G1 stage (Jacobsen and Olszewski 1991, Plant Physiol. 97, 409-414). Following GA3 treatment of developmentally arrested flowers, pollen mother-cell development resumes and is synchronous. The present study examines gibberellin-induced changes in the translatable mRNA populations of developmentally arrested stamens and of vegetative shoots of the gib1 mutant. Following rescue of developmentally arrested stamens by treatment with GA3, we consistently detected increases and decreases in the abundance of 14 and 20 in-vitro translation products, respectively. Some of these changes were first detected 8 h post treatment and therefore represent the first changes observed in stamens whose development has been rescued by GA3 treatment. In vegetative gib1 shoots, the abundance of 13 in-vitro translation products decreased within 6-24 h after GA3 treatment. However, no in-vitro translation products that increased in abundance after GA3 treatment were detected.

Application of DNA profiling to paternity testing during early pregnancy

Four probes that recognize D2S44, D17S79, D4S163 and D18S27 loci, were used to produce DNA profiles of 8- to 10-week-old chorionic villus samples and from blood samples of their respective parents. A total of 30 pedigrees were analyzed. The results showed strict Mendelian inheritance. The cumulative paternity index (PI) and probability of paternity (W) obtained with D2S44, D17S79 and D4S163 loci were sufficient to exceed the required standard (PI > 369, W > 99.73) for assertion of paternity for all pedigrees tested. Therefore, these three loci are likely to satisfy the paternity test requirements in the majority of paternity cases, involving unrelated individuals, in the Chinese Han population. The other combinations of three loci did not produce high enough values for all cases, but all W values were > 98%. The results show that, using DNA from chorionic villi, these polymorphic loci can resolve cases of disputed paternity during early pregnancy.

Relationship between Proline and Abscisic Acid in the Induction of Chilling Tolerance in Maize Suspension-Cultured Cells

Both proline and abscisic acid (ABA) induce chilling tolerance in chilling-sensitive plants. However, the relationship between proline and ABA in the induction of chilling tolerance is unclear. We compared the time course of the increase in chilling tolerance induced by proline and ABA, and the time course of the uptake of both into the cultured cells of maize (Zea mays L. cv Black Mexican Sweet) at 28[deg]C. The plateau of proline-induced chilling tolerance preceded by 12 h the plateau of ABA-induced chilling tolerance. The uptake of exogenous ABA into the cells reached a plateau in 1 h, whereas the uptake of exogenous proline gradually increased throughout the 24-h culture period. Although the proline content in ABA-treated cells was 2-fold higher than in untreated cells at the end of the 24-h ABA treatment at 28[deg]C, the correlation between the endogenous free proline content and the chilling tolerance in the ABA-treated cells was insignificant. Isobutyric acid treatment, which resulted in a larger accumulation of proline in the cells than ABA treatment, did not increase chilling tolerance. The induction of chilling tolerance by proline and ABA appeared to be additive. Cycloheximide inhibited ABA-induced chilling tolerance, but it did not inhibit proline-induced chilling tolerance. Newly synthesized proteins accumulate in ABA-treated cells at 28[deg]C while the chilling tolerance is developing (Z. Xin and P.H. Li [1993] Plant Physiol 101: 277-284), but none of these proteins were observed in the proline-treated cells. Results suggest that proline and ABA induce chilling tolerance in maize cultured cells by different mechanisms.

Copper status and requirement during the dry period and early lactation in multiparous Holstein cows

Eighteen multiparous Holstein cows were assigned randomly to three treatments at the beginning of the dry period (8 wk before expected parturition). Treatments were: 1) the basal diet containing 5.5 ppm of Cu (control), 2) the basal diet supplemented with 10 ppm of Cu, and 3) the basal diet supplemented with 20 ppm of Cu. The objectives were to measure the changes of Cu and other trace mineral element concentrations in blood and liver from the onset of the dry period (approximately 8 wk prepartum) to 8 wk postpartum and to assess the requirement of Cu during this time. Liver Cu concentration in the control group declined continuously during the 8-wk dry period, and the nadir occurred at parturition. This decline was prevented by dietary Cu supplementation of 10 or 20 ppm. Liver Cu concentration in the control group started to increase slowly after the dramatic decline. Liver Zn concentration changed cubically as a function of week during the treatment period. Plasma Cu and Zn exhibited a quadratic pattern as a function of week. The plasma Cu concentration was lowest 5 wk prior to parturition.

Effect of copper status on luteinizing hormone secretion in dairy steers

Two experiments were conducted to examine the effects of Cu status on neuroendocrine regulation of LH secretion in dairy steers. In Experiment 1, 18 Holstein steers were assigned randomly to treatment groups in a completely randomized design. Treatments consisted of basal diet alone (control) or supplemented with 5 ppm of Mo or with 20 ppm of Cu. At 8 and 16 wk, Cu concentrations in liver were higher in the group receiving Cu and lower in the group receiving Mo than in the control. Pulse frequencies of LH were not affected by any treatment. Serum LH concentration at 16 wk tended to be lower in the group receiving Mo than in either the control or the group receiving Cu. The ability of the pituitary gland to release LH in response to GnRH was not affected at 17 wk. Concentrations of LH in the pituitary glands were lower in the group receiving Mo than in that receiving Cu or in the controls. No differences in Cu or Mo concentrations were observed in pituitary, median eminence, or hypothalamic tissues. In Experiment 2, 12 Holstein steers were assigned to treatment groups receiving the basal diet supplemented with either 20 ppm or Cu or with 10 ppm of Mo. Spontaneous and GnRH-induced secretion of LH were not influenced by treatments after 8 mo of experiment. Reduction in Cu status has little effect on the endogenous secretion of LH in dairy steers.

Alteration of Gene Expression Associated with Abscisic Acid-Induced Chilling Tolerance in Maize Suspension-Cultured Cells

ABA induces chilling tolerance in maize (Zea mays L., cv Black Mexican Sweet) suspension-cultured cells at 28[deg] C when ABA was added to the culture medium at least 6 h prior to chilling (4[deg] C), and this induction can be inhibited by blocking protein synthesis with cycloheximide treatment (Z. Xin, P.H. Li [1992] Plant Physiol 99: 707-711). De novo synthesis of proteins and changes in poly(A+) RNAs were investigated during the ABA induction of chilling tolerance at 28[deg] C as well as during chilling exposure. At 28[deg] C, ABA increased the net synthesis of 11 proteins. Five of these proteins, whose net synthesis was also increased by chilling (4[deg] C), were called group I ABA-induced proteins; the remaining six proteins, whose net synthesis was not altered by chilling, were called group II ABA-induced proteins. Chilling suppressed the net synthesis of three proteins. ABA treatment prior to chilling did not alleviate this suppression. ABA applied at the inception of chilling induced neither chilling tolerance nor accumulation of any of the group II proteins; however, once the group II proteins appeared, they were continually synthesized even in a chilling regimen. ABA induced seven in vitro translation products at 28[deg] C. Three of these products could also be induced by chilling; the remaining four were induced by ABA only at 28[deg] C. These results suggest that ABA-induced alteration of protein synthesis at 28[deg] C is associated with an increased chilling tolerance in maize suspension-cultured cells.

Abscisic Acid-induced chilling tolerance in maize suspension-cultured cells

The induction of chilling tolerance by abscisic acid (ABA) in maize (Zea mays L. cv Black Mexican Sweet) suspension cultured cells was examined. Cell viability during exposure to chilling was estimated by triphenyl tetrazolium chloride reduction immediately after chilling and a filter paper growth assay. Both methods yielded comparable results. Chilling tolerance was induced by transferring 5-day-old cultures (late log phase) to a fresh medium containing ABA (10 to 100 micromolar). The greatest chilling tolerance was achieved with ABA at 100 micromolar. Growth of cells was inhibited at this concentration. After a 7-day exposure to 4 degrees C in the dark, the survival of ABA-treated cells (100 micromolar ABA, 28 degrees C for 24 h in the dark) was sevenfold greater than untreated cells. Effective induction of chilling tolerance was first observed when cells were held at 28 degrees C for 6 hours after adding ABA. No tolerance was induced if the culture was chilled at the inception of ABA treatment. Induction of chilling tolerance was inhibited by cycloheximide. These results indicate that ABA is capable of inducing chilling tolerance when ABA-treated cells are incubated at a warm temperature before exposure to chilling, and this induction requires de novo synthesis of proteins.

Influence of cation-anion balance on feed intake, body weight gain, and humoral response of dairy calves

The objective of this study was to examine the influence of diets with varying cation-anion balance on performance and humoral responses in young, growing dairy calves. Twenty-eight Holstein and 4 Jersey female calves were blocked at 56 to 70 d after birth according to breed and age and assigned randomly to dietary treatments of 0, 21, 37, and 52 meq(Na + K) - Cl/100 g of dietary DM. Diets were based on cracked corn, dried brewers grains, and oats and were fed for 8 wk. Feed intake and average daily gain tended to increase quadratically, being highest for calves fed the +37-meq diet and lowest for those fed the 0-meq diet. Blood and urine pH increased linearly with increasing dietary cation-anion balance. Plasma Ca increased linearly, and Mg and Cl decreased linearly with increasing cation-anion balance. Plasma Na and P were unaffected by dietary treatments. Urinary Ca, Mg, and Cl excretions decreased linearly; urinary P, Na, and K excretion increased linearly with increasing dietary cation-anion balance. Blood pH increased linearly with increasing dietary cation-anion balance. Blood partial pressure of CO2 and HCO3 increased concurrently with increasing dietary cation-anion balance. Results indicate that altering cation-anion balance may impact DMI and average daily gain in the young ruminant.

Effects of copper sources and dietary cation-anion balance on copper availability and acid-base status in dairy calves

Twenty-four Holstein and Jersey calves (14 Holstein), 4 to 11 d of age, were assigned randomly to six treatments in a 2 x 3 factorial arrangement to examine the effects of Cu sources and dietary cation-anion balance on Cu availability and acid-base balance. Treatments were cationic basal diet (20 meq of dietary cation-anion balance on a DM basis), cationic basal diet supplemented with CuO, cationic basal diet supplemented with CuSO4, anionic basal diet (-10 meq), anionic basal diet supplemented with CuO, and anionic basal diet supplemented with CuSO4. Copper sources did not show any effect on growth of calves. The cationic diet increased calf growth compared with the anionic diet at wk 12 of the experiment. Blood pH was increased by the cationic diet in comparison with the anionic diet at wk 8 and 12. Blood pH also was increased by CuSO4 compared with CuO treatment in the early period of the treatment. Blood bicarbonate concentration was decreased by CuO and the anionic diet. Interactions between Cu sources and cation-anion balance were found for blood pH and bicarbonate concentration. Liver Cu concentration was increased by CuSO4 but not by CuO supplementation compared with control. Therefore, CuSO4 was found to be highly available, whereas CuO was a very poorly available source of Cu for young calves.

Effects of copper status on neutrophil function, superoxide dismutase, and copper distribution in steers

Twelve Holstein steers in a completely randomized block design were fed either a basal diet (concentrate:silage or hay at a DM ratio of 35:65) plus Cu sulfate at 20 ppm of Cu (Cu-supplemented diet) or a basal diet plus ammonium molybdate to obtain 10 ppm of Mo (Cu-depleting diet) on a DM basis in the whole diet for 8 mo. Supplemental Mo was utilized in the Cu-depleting diet to develop a Cu-deficient group. Molybdenum slowly accumulated in the liver in the group fed the Cu-depleting diet. Copper concentrations in the liver and polymorphonuclear neutrophils decreased in the Cu-deficient group compared with the Cu-sufficient group. Plasma Cu concentration did not change during the trial for the Cu-sufficient group. In the Cu-deficient group, plasma Cu concentrations increased during the first 3 mo of the trial, then declined, and remained unchanged for the last 5 mo. Superoxide dismutase activities in red blood cells, polymorphonuclear neutrophils, and whole blood decreased in the Cu-deficient group. Phagocytic capacity was not affected by Cu status, but killing capacity was decreased by low Cu status in the Cu-deficient group by the end of the trial. Glutathione peroxidase activity was unaffected by Cu status. Clinical symptoms of Cu-deficiency were not observed in this trial; there was no evidence of blood hemoglobin or BW gain difference between the two groups. In this study, Cu status affected its distribution in the tissues and related enzyme activities as well as bactericidal function of neutrophils.

Influence of calcium chloride on systemic acid-base status and calcium metabolism in dairy heifers

Twenty heifers (12 Holsteins and 8 Jerseys) ranging from 15 to 22 mo of age (SD = 2.2 mo) and weighing 271 to 486 kg (SD = 72 kg) were offered diets containing 0, .5, 1, and 1.5% CaCl2 for 3 wk followed by a 1-wk readjustment period to evaluate the effect of CaCl2 on acid-base status, diuresis, and Ca metabolism. These evaluations were conducted under conditions simulating changes in dietary cation-anion balance that potentially can be utilized as prophylaxis for parturient paresis during transition from dry cow period to lactation. Free proton concentration in blood increased and blood bicarbonate decreased with increasing dietary CaCl2. Plasma protein and blood hematocrit were unaffected by dietary CaCl2. Plasma Ca and urinary hydroxyproline excretion also were unaffected, but urinary Ca excretion rose with increasing dietary CaCl2, possibly reflecting either increased bone mobilization or intestinal absorption of Ca. Elevating dietary Cl increased both plasma Cl and urinary Cl excretion. During the readjustment period, all differences caused by CaCl2 disappeared. Based on the responses of acid-base status and Ca metabolism to the different dietary concentrations of CaCl2, we suggest that feeding 1% CaCl2 to dry cows for 3 wk prepartum could be a suitable method to prevent parturient paresis without causing detrimental acid-base disturbances.

Role of sulfur and chloride in the dietary cation-anion balance equation for lactating dairy cattle

Ten Holstein cows averaging 120 d in lactation were arranged in replicated 5 x 5 Latin squares with 3-wk periods to evaluate the role of sulfur (S) in the dietary cation-anion balance equation. Diets were based on corn silage in Exp. 1 and sorghum silage in Exp. 2. Supplemental S and chloride (Cl) from the double sulfate of potassium and magnesium and CaCl2 were used to manipulate dietary cation-anion balance from 0 to +30 meq when expressed as meq [(Na + K)-(Cl + S)]/100 g diet DM and from +19 to +49 meq when expressed as meq [(Na + K)-Cl]/100 g diet DM. Blood pH was not affected by cation-anion balance, although both S and Cl supplementation tended to lower pH. Blood HCO3- and urine pH decreased and plasma calcium (Ca) and urinary Ca excretion increased as anion was added to the diet. Milk fat production tended to be increased by the low S supplementation. Dietary Cl and S had similar effects on acid-base status. Therefore, we suggest that S be included with Cl in the dietary cation-anion balance equation for lactating dairy cows as follows: meq [(Na + K)-(Cl + S)]/100 g diet DM. Although response of acid-base status to S and Cl was similar, as more data comparing the acidogenicity of S vs Cl become available, it may be necessary to include a modifying coefficient for S in the equation to adjust for differences between S and Cl in acid-generating potential. This coefficient may be further dependent on the dietary source of S.

[Effect of qigong on sympathetico-adrenomedullary function in patients with liver yang exuberance hypertension]

By using the differential diagnosis of traditional Chinese medicine to determine the types of hypertension, using the diagnosis of western medicine (WM) to determine the phases of hypertension, 61 inpatients of Liver Yang exuberance type hypertension were randomly divided into Qigong group and WM group. The patients in the Qigong group were treated with both Qigong and antihypertensive drugs at low dosage, but those in the WM group were treated with the drugs alone. Several laboratory tests concerning sympathetico-adrenomedullary functions were conducted twice respectively at 1st and 9th week after hospitalization of the patients. The results indicated that the Qigong group after treatment of 9 weeks had more cases with normal sympathetico-adrenomedullary functions than it had before the treatment, and that their urinary CA, E, NE decreased, MHPG-SO4 increased, plasma cAMP and cGMP got down, but cAMP/cGMP ratio got up. It suggested that Qigong could modulate the sympathetico-adrenomedullary functions of patients with Liver Yang exuberance type hypertension.

Effect of reactivity rate and particle size of magnesium oxide on magnesium availability, acid-base balance, mineral metabolism, and milking performance of dairy cows

Four ruminally fistulated Holstein cows were arranged in a 4 x 4 Latin-square design. Treatments consisted of a control diet and three diets containing 4% MgO (DM basis) with increasing reactivity rates (A, B, C). Diets contained corn silage and concentrate at a 40:60 ratio (DM) and were fed at 95% of ad libitum intake. Total acid-consuming capacity and solubility of MgO in vitro paralleled particle size and agreed with the solubilities in the rumen. Milk fat percentage, but not milk yield, was increased by all three MgO diets. Ruminal pH was elevated by the MgO diets across all 8 h postfeeding. MgO, reactivity A diet tended to increase ruminal acetate, total VFA production, milk yield, milk fat yield, and milk fat percentage. Effect of time postfeeding on acetate and propionate production was significant; 2 to 6 h postfeeding was the period most responsive to the diets. No significant influence on blood acid-base balance was observed. On the basis of urinary excretion of Mg, MgO sources with smaller particles are more available to cattle. Both Ca and Cl metabolism appeared to be affected by reactivity rate of MgO.