Biomedical subjects

Ying Huang

Publications and source records attributed to Ying Huang.

At least 73 records · Page 4Linked to original sources

PubMed2006

[Clinical value of barium swallow in observing esophageal tumor regression during radiotherapy].

BACKGROUND & OBJECTIVE: Barium swallow is widely used to observe the treatment response of esophageal squamous cell carcinoma (ESCC) and as a routine examination for long-term follow-up in China because of its convenience and inexpensiveness. This study was to observe esophageal tumor regression by barium swallow during radiotherapy, analyze the correlations of tumor regression speed to short-term response and long-term survival, and evaluate the clinical value of barium swallow during radiotherapy for ESCC. METHODS: Clinical data from 94 patients with ESCC, treated with radiotherapy (39 patients) or chemoradiotherapy (55 patients) from Jan. 2001 to Jun. 2003 at Cancer Center of Sun Yat-sen University, were retrospectively reviewed. Of the 94 patients, 18 (19.1%) were at stage II, 36 (36.3%) at stage III, and 42 (44.6%) at stage IV. Barium swallow was performed at the radiation dose of 40 Gy and the radiation end, and the X-ray appearance was classified according to Zhengzhou Meeting criteria. The patients were divided into 3 groups according to their tumor regression speed: Group A had rapid regression, with the X-ray appearance classified as grade I or II at 40 Gy, Group B had slow regression, with the X-ray appearance classified as grade III or IV at 40 Gy, but as grade I or II at the radiation end, Group C had obvious residual tumors, with the X-ray appearance kept being classified as grade III or IV till radiation end. The correlations of tumor regression speed to short-term response and long-term survival were analyzed. RESULTS: The complete response (CR) rates were 100.0% in Group A, 65.2% in Group B, and 28.3% in Group C (P<0.001), the 3-year survival rates were 44.0%, 24.2%, and 17.3%, respectively (P<0.001). Multivariate Cox regression analysis showed that short-term response and M stage were independent prognostic factors. The 3-year survival rates of CR patients were 44.0% in Group A, 32.6% in Group B, and 42.2% in Group C (P=0.814). The locoregional failure rates were 50% in Group A, 88% in Group B, and 81% in Group C, and the occurrence rates of severe radiation-related complications were 19%, 0%, and 6%, respectively. CONCLUSIONS: Barium swallow during radiotherapy for ESCC could be used to judge tumor regression speed, which is closely related to short-term response. Short-term response is an important prognostic factor of ESCC.

Adult↗

PubMed2006

[Role of Foxp3 expression and CD4+CD25+ regulatory T cells on the pathogenesis of childhood asthma].

OBJECTIVE: To explore the impact of Foxp3 expression and CD(4)(+)CD(25)(+) regulatory T cells on pathogenesis of childhood asthma. METHODS: Totally 15 patients with acute asthma exacerbation, 15 children with asthma remission and 10 children who were hospitalized for skeleton deformity without atopic disorders or history of allergic diseases or respiratory infections within a month as controls were recruited in this study from Sep. 2004 to Mar. 2005. The percentage of CD(4)(+)CD(25)(+) T cells were detected by 2-color flow cytometry. The levels of interleukin (IL)-4, IL-10, interferon (IFN)-gamma, transforming growth factor (TGF)-beta in plasma and supernatant were assayed by ELISA. Both the asthmatic children and the control children were selected to induce sputum by hypertonic saline. Sputum was processed for detecting the expression of Foxp3-mRNA. The expression of Foxp3-mRNA in both sputum and PBMC was detected by semi-quantitative RT-PCR with beta-actin as internal control. RESULTS: The percentage of CD(4)(+)CD(25)(+) regulatory T cells in exacerbation and remission asthmatic children was significantly lower than that of the control children both prestimulation [(10.1 +/- 2.1)% vs. (15.5 +/- 2.7)%, (11.7 +/- 2.5)% vs. (15.5 +/- 2.7)%, P < 0.05] and poststimulation with PHA [(12.4 +/- 2.3)% vs. (26.9 +/- 3.8)%, (17.3 +/- 3.2)% vs. (26.9 +/- 3.8)%, P < 0.05]. The percentage of CD(4)(+)CD(25)(+) regulatory T cells was significantly higher after PHA stimulation in normal children [(15.5 +/- 2.7)% vs. (26.9 +/- 3.8)%, P < 0.01]. The expression of Foxp3-mRNA (Foxp3/beta-actin) in asthmatic children was significantly lower than that in the control children in both PBMC and induced sputum. The expression of Foxp3-mRNA in PBMC was significantly higher after PHA stimulation in the control children (0.77 +/- 0.22 vs. 1.07 +/- 0.21, P < 0.05). However, there was no significant difference in Foxp3-mRNA expression in asthmatic children pre and post PHA stimulation. A significant positive correlation between the Foxp3-mRNA expression and the percentage of CD(4)(+)CD(25)(+) regulatory T cells was detected. The levels of IFN-gamma and TGF-beta were significantly lower in asthmatic children than those in the control children, and the levels of IFN-gamma and TGF-beta correlated positively with Foxp3-mRNA expression and the percentage of CD(4)(+)CD(25)(+) regulatory T cells. The level of IL-4 both in plasma and supernatant was higher in asthmatic children. The levels of IL-10 was higher only in exacerbation than in control children, the levels of IL-4 and IL-10 had no correlation with Foxp3-mRNA expression and the percentage of CD(4)(+)CD(25)(+) regulatory T cells. CONCLUSION: Insufficient secretion of TGF-beta, decreased Foxp3 expression, insufficient number of CD(4)(+)CD(25)(+) regulatory T cells and the defective ability of converting CD(4)(+)CD(25)(-) T cells to CD(4)(+)CD(25)(+) regulatory T cells might play an important role in pathogenesis of asthma.

Asthma↗

PubMed2006

[The relationship between histone acetylation modification and IFN-gamma responsive gene regulation].

OBJECTIVES: To study the role of histone modification in the regulation of IFN-gamma-activated gene using chromatin immunoprecipitation technique. METHODS: Real-time PCR was used to measure the mRNA level of interferon-gamma-inducible protein 10 (IP-10) in Hela cells. Chromatin immunoprecipitation combined with Real-time PCR was used to check the histone H4 acetylation level at IFN-stimulated response element (ISRE) locus of IP-10 gene. RESULTS: IP-10 was strongly activated by IFN-gamma. The histone H4 deacetylation happened at the ISRE locus when IP-10 was induced by IFN-gamma. The activation of IP-10 and the deacetylation of histone H4 at the ISRE site induced by IFN-gamma were inhibited or blocked by histone deacetylase (HDAC) inhibitor trichostatin A (TSA). CONCLUSION: The histone H4 deacetylation at the ISRE site is related with the activation of IP-10 by IFN-gamma.

Acetylation↗

PubMed2006

[The study on reversing mechanism of multidrug resistance of K562/A02 cell line by curcumin and erythromycin].

OBJECTIVE: To investigate the effects of curcumin (Cur) and erythromycin (EM) on multidrug resistance (MDR) reversal of K562/A02 cell line and their mechanism. METHODS: MTT assay was employed to determine the sensitivity of Cur, EM-treated K562/A02 cells to adriamycin (ADM). Flow cytometry was used to measure intracellular mean fluorescence intensity (MFI) of daunorubicin (DNR). P-gp expression was determined by immunohistochemistry. RT-PCR technique was used to examine the mdr1 mRNA level. RESULTS: IC(50) of ADM in K562/A02 cells was decreased when treated with Cur or EM, and the reversal times (RvT) was 4.9, 3.7 respectively. The RvT reached to 11.3 when treated with Cur (2.5 microg/ml) combined with EM (120 microg/ml). The DNR MFI in K562/A02 cells was significantly lower than that in K562 cells (P < 0.01), and was increased significantly when treated with Cur (2.5 microg/ml) or EM (120 microg/ml) (P < 0.05). There was no significant difference between DNR MFI of K562/A02 cells treated with Cur (2.5 microg/ml) or EM (120 microg/ml). Immunohistochemistry showed that P-gp expression was significantly higher in K562/A02 cells than in K562 cells (P < 0.01), and was reduced in K562/A02 cells treated with each (P < 0.01), though being still higher than that in K562 cells (P < 0.01). P-gp expression of K562/A02 cells treated with each drug for 5 days were lower than that for 3 days (P < 0.01), and lowered further when treated with Cur and EM together (P < 0.01). Mdr1 mRNA level in K562/A02 cells was higher than in K562 cells (P < 0.01), and was decreased when treated with each of the drugs (P < 0.01). The mdr1 mRNA level of K562/A02 cells treated with Cur (2.5 microg/ml) plus EM (120 microg/ml) was decreased most significantly than that treated with other group of drugs. After 5 day treatment the mdr1 mRNA level of K562/A02 cells with Cur (2.5 microg/ml) was lower than that with EM 120 microg/ml (P < 0.01). CONCLUSIONS: Either Cur or EM can partly reverse the multidrug resistance of K562/A02 cells and decrease the expression and function of P-gp in a time-dependent way. MDR reversing effect of Cur combined with EM is stronger than that of Cur or EM alone.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed2006

[Screening of proteins interacting with hepatitis C virus NS3 from T7-phage display library].

OBJECTIVE: To screen and identify proteins that interact with hepatitis C virus NS3 by means of T7-phage display system. METHODS: Hepatitis C virus NS3 was expressed by prokaryotic expression and used as a selected molecule to biopan the T7 select human liver cDNA library; the selected positive clones were identified using DNA sequencing and analyzed with BLAST program in GenBank. RESULTS: After BLAST analysis in all the positive clones, the proteins which interacted with the hepatitis C virus NS3 were found to be serpin peptidase inhibitor, clade A, member 1 (SERPINA1) and cyclophilin-LC. CONCLUSION: T7-phage display system is a convenient, rapid and effective method for screening interacting proteins. The proteins thus selected will provide an important means for studying the pathogenesis and carcinogenesis of HCV.

Cell Line↗

PubMed2006

[Inhibition of HBV replication and antigen expression by RNA interference against different targets].

OBJECTIVES: To observe the inhibition of HBV replication and antigen expression by RNA interference aimed at different parts of the HBV genome. METHODS: Following the rules of shRNA expression vector design and construction, we constructed seven kinds of sequence specific vectors and two kinds of mutant shRNA expression ones. We then cotransfected those shRNA and HBV expression vectors into HepG2 cells using lipofectamine2000. The level of HBV replication was investigated using Southern blot and the antigen expression using ELISA. RESULTS: The replication of HBV DNA was inhibited by many shRNAs, especially the ones against P1, S2, C2, S1 and X. The inhibition rate against P1 was as high as 95%. Results obtained with ELISA showed that the shRNAs targeting C2, C1 and S2 had high rates of inhibition to HBsAg. CONCLUSION: The replication and antigen expression of HBV could be inhibited by shRNAs aimed at four different open read frames, and higher inhibition rates of HBV replication and surface antigen expression could be obtained by P1 and C2, respectively.

Gene Expression↗

PubMed2006

[Diversity of actinomycetes associated with root-knot nematode and their potential for nematode control].

Twenty actinomycetes were isolated from root-knot nematode eggs and females collected from 11 plant root samples infested by Meloidogyne spp.. The isolates were assigned to the genera Streptomyces, Nocardia and Pseudonocardia respectively, based on analysis of morphological characteristics, cell-wall DAPs and 16S rRNA gene sequences. 80% of them were streptomycetes. Biocontrol potential of the isolates against Meloidogyne hapla was evaluated in liquid culture in vitro. The average percentages of egg parasitism, egg hatching, and juvenile mortality were 54.1, 40.4 and 26.2, respectively. Three Streptomyces strains and one Nocardia strain with high pathogenicity in vitro were selected to determine their ability to reduce tomato root galls in greenhouse. The results demonstrated good biocontrol efficacy (31.4%-56.4%) of the strains.

Actinobacteria↗

PubMed2006

[Dynamic analysis of heart rate variability based on wavelet transform].

The analysis of heart rate variability (HRV) has become a tool for noninvasively detecting the cardiovascular modulation of autonomic nervous system. Traditional analysis in frequency domain mainly includes calculating the power and detecting the peak frequency of each physiological frequency band. Whether employing the classical method or AR model to estimate the spectrum, the approximate stationarity of HRV is presupposed. Only in short term analysis can data meet this condition, while in long term the nonstationarity of HRV notably appears. A dynamic analysis method based on wavelet transform was proposed in this paper, which not only can obtain the traditional indices in frequency domain, but can compute their dynamic values varying with time, called short-time power and short-time LF/HF ratio. The latter can dynamically evaluate the activity of autonomic nervous. Finally the method was applied to trace the balance of autonomic nervous in Atropin drag experiment.

Adult↗

PubMed2006

[Isolation, classification and antimicrobial activity of endophytic actinomycetes from plant leaves].

Leave samples of Paeonia lactiflora and Trifalium repens were collected from Sichuan Province and Beijing respectively to study their endophytic actinmycetes. After a well-established surface-sterilized procedure, the samples were plated on agar media of TWYE, HV, YECD, NA and WA, followed by incubation at 28 degrees C for 2 - 4 weeks. With the help of light microscope, 15 actinomycetes strains were isolated from the plates. Comparison of cultural features and fingerprinting analyses of BOX-PCR products were performed to cluster the isolates, with the result that all the strains were assigned to 12 different genotypes, half of them from Paeonia lactiflora and half from Trifalium repens. A combination of morphological and 16S rRNA gene sequence data showed that except strains C4 and C5, which belonged to Pseudonocardia, 13 of the isolates were streptomycetes. Most isolates share high 16S rRNA gene sequence similarities to known type strains. However, strain C12 shares low values, 96.6% in maximum, and strain C5 shares 97.9% in maximum; more assays are needed to ascertain their taxonomic positions. In the tests of antimicrobial activity against 7 bacteria, 3 fungi and 1 yeast, 11 isolates were positive in one or more tests, and 55% of the positive ones could inhibit the growth of Rhizoctonia solani, a significant pathogen of plants.

Actinobacteria↗

PubMed2005

Atherosclerosis in mice is not affected by a reduction in tissue factor expression.

OBJECTIVE: To determine whether tissue factor (TF) contributes to the progression of atherosclerotic lesions in mice. METHODS AND RESULTS: We determined the effect of a 50% reduction of TF levels in all cells on atherosclerosis in apolipoprotein E-deficient (apoE(-/-)) mice. No differences were observed in the extent of atherosclerosis in apoE(-/-)/TF(+/+) and apoE(-/-)/TF(+/-) mice fed regular chow for 34 weeks. Atherosclerosis could not be analyzed in apoE(-/-) mice expressing low levels of TF because of premature death of these mice. Macrophages are a major source of TF in atherosclerotic plaques. Therefore, in a second series of experiments, we investigated the effect on atherosclerosis of selectively reducing hematopoietic cell-derived TF by transplanting bone marrow from mice expressing low levels of TF into low-density lipoprotein receptor deficient (LDLR(-/-)) mice. Atherosclerosis within the arterial tree and aortic root were similar in LDLR(-/-) mice with low-TF bone marrow compared with control bone marrow (TF(+/+) or TF(+/-)) after 4 and 16 weeks on an atherogenic diet. Furthermore, the cellular composition of the aortic root lesions was similar between the 2 groups. CONCLUSIONS: Our data indicate that either a 50% reduction of TF in all cells or a selective reduction in hematopoietic cell-derived TF does not affect the development of atherosclerotic lesions in mice.

Animals↗

PubMed2005

Cloning and characterization of a p53 and DNA damage down-regulated gene PIQ that codes for a novel calmodulin-binding IQ motif protein and is up-regulated in gastrointestinal cancers.

We have identified a p53 and DNA damage-regulated gene that encodes a novel IQ motif protein, which we have named p53 and DNA damage-regulated IQ motif protein (PIQ). PIQ has two isoforms, long (PIQ-L) and short (PIQ-S), and both bind to calmodulin in the presence and absence of calcium. PIQ expression is down-regulated by p53 and DNA damage-inducing agents, whereas PIQ itself represses the expression of p53 up-regulated modulator of apoptosis that is a key mediator of p53-induced apoptosis. Thus, PIQ is a novel protein that may function to bridge a crosstalk between p53 and calmodulin-regulated cellular processes. We further show that PIQ expression is up-regulated in a number of primary colorectal and gastric tumors when compared with matching normal tissues, suggesting that PIQ may be involved in tumorigenesis and could serve as a valuable diagnostic/prognostic marker for gastrointestinal tumors.

Amino Acid Sequence↗

PubMed2005

Carbon microspheres with supported silver nanoparticles prepared from pollen grains.

In this paper, we present a new method to fabricate carbon microspheres with supported silver nanoparticles on the surfaces. In this method, pollen grains were first treated with AgNO(3) aqueous solution, then preoxidized in air at 300 degrees C and carbonized in nitrogen at 600 degrees C, resulting in the silver/carbon nanocomposites. The silver/carbon nanocomposites were characterized by means of SEM, TEM, TG, and XRD. The size and distribution of the silver nanoparticles on the carbon microsphere surface could be controlled by tuning the AgNO(3) treatment conditions.

Journal Article↗

PubMed2005

Interferon-alpha-induced expression of phospholipid scramblase 1 through STAT1 requires the sequential activation of protein kinase Cdelta and JNK.

Phospholipid scramblase 1 (PLSCR1), a calcium-binding protein that either inserts into the plasma membrane or binds to genomic DNA in the nucleus, has been shown to contribute to the cell proliferation, differentiation, and apoptosis as well as antiviral activity of interferon (IFN). The expression of PLSCR1 protein is also known to be markedly increased in response to IFN and to some differentiation inducing agents such as all-trans retinoic acid, but the precise mechanisms of this response remain to be investigated. In this study, we show that the protein kinase Cdelta (PKCdelta)-specific inhibitor rottlerin and the dominant negative mutant of PKCdelta significantly antagonized IFN-induced PLSCR1 expression. The influence of PKCdelta on IFN-mediated induction of PLSCR1 was dependent upon the phosphorylation of STAT1 at Ser-727. Furthermore, PKCdelta-mediated activation of STAT1 required the activation of JNK, as the inhibition of JNK activity by its specific inhibitor or transfection of its dominant negative mutant suppressed both serine phosphorylation of STAT1 and PLSCR1 expression but not the activation of PKCdelta. In conclusion, our results suggest that the induction of PLSCR1 transcription through STAT1 depends upon sequential activation of PKCdelta and JNK.

Acetophenones↗

PubMed2005

[Blockade of NMDA receptor enhances corticosterone-induced downregulation of brain-derived neurotrophic factor gene expression in the rat hippocampus through cAMP response element binding protein pathway].

High concentration of corticosterone leads to morphological and functional impairments in hippocampus, ranging from a reversible atrophy of pyramidal CA3 apical dendrites to the impairment of long-term potentiation (LTP) and hippocampus-dependent learning and memory. Glutamate and N-methyl-D-aspartate (NMDA) receptor play an important role in this effect. Because of the importance of brain-derived neurotrophic factor (BDNF) in the functions of the hippocampal neurons, alteration of the expression of BDNF is thought to be involved in the corticosterone effect on the hippocampus. To determine whether change in BDNF in the hippocampus is involved in the corticosterone effect, we injected corticosterone (2 mg/kg, s.c.) to Sprague-Dawley rats and measured the mRNA, proBDNF and mature BDNF protein levels in the hippocampus. We also measured the phosphorylation level of the transcription factor cAMP response element binding protein (CREB). Furthermore, we intraperitoneally injected NMDA receptor antagonist MK801 (0.1 mg/kg) 30 min before corticosterone administration to investigate whether and how MK801 affected the regulation of BDNF gene expression by corticosterone. Our results showed that 3 h after single s.c. injection of corticsterone, the expression of BDNF mRNA, proBDNF and mature BDNF protein decreased significantly (P<0.01). MK801 promoted the downregulation of BDNF gene expression in the rat hippocampus by corticosterone. We also found that either applying corticosterone or co-applying corticosterone with MK801 downregulated the phosphoration level of CREB, the latter (corticosterone plus MK801) being more effective (P<0.05). Taken together, our results indicate that corticosterone downregulates BDNF gene expression in the rat hippocampus through CREB pathway and that blockade of NMDA receptor enhances this effect of corticosterone in reducing BDNF expression.

Animals↗

PubMed2005

Genotoxic and endoplasmic reticulum stresses differentially regulate TRB3 expression.

TRB3 has recently been identified as a potential pro-apoptotic protein that may modulate the Akt/PKB-dependent signaling pathway. Here we report that TRB3 expression is strongly upregulated by endoplasmic reticulum (ER) stress-inducing agents that (1) promote ER Ca2+ pool depletion or (2) disrupt protein trafficking. Genotoxic stress (DNA damage)-inducing agents, by contrast, downregulate TRB3 expression and appear to do so through both p53-dependent and -independent mechanisms. To the best of our knowledge, TRB3 is the first gene that is upregulated by ER stress and downregulated following genotoxic stress. Collectively, these findings highlight the importance of stress-specific signaling cascades as well as point out the seemingly divergent roles that TRB3 may play in the cellular stress response.

Cell Cycle Proteins↗

PubMed2005

ATID: a web-oriented database for collection of publicly available alternative translational initiation events.

SUMMARY: Alternative translational initiation is an important cellular mechanism contributing to the diversity of protein products and functions. We develop a database that provides a comprehensive collection of alternative translational initiation events. The purpose of this alternative translational initiation database (ATID) is to facilitate the systematic study of alternative translational initiation of genes. The current version of database contains 300 genes from Homo sapiens, Mus musculus and other species. Each of the genes has two or more isoforms due to alternative translational initiation. Resources in ATID, including gene information, alternative products of genes and domain structures of isoforms, are provided through a user-friendly web interface. AVAILABILITY: The ATID database is available for public use at http://bioinfo.au.tsinghua.edu.cn/atie/.

Amino Acid Sequence↗

PubMed2005

Membrane transporters and channels in chemoresistance and -sensitivity of tumor cells.

Membrane transporters play important roles in mediating chemosensitivity and -resistance of tumor cells. ABC transporters, such as ABCB1/MDR1, ABCC1/MRP1 and ABCG2/BCRP, are frequently associated with decreased cellular accumulation of anticancer drugs and multidrug resistance of tumors. SLC transporters, such as folate, nucleoside, and amino acid transporters, commonly increase chemosensitivity by mediating the cellular uptake of hydrophilic drugs. Ion channels and pumps variably affect sensitivity to anticancer therapy by modulating viability of tumor cells. A pharmacogenomic approach, using correlations between drug potency and transporter gene expression in multiple cancer cell lines, has shown promise for identifying potential drug-transporter relationships and predicting anticancer drug response, in an effort to optimize chemotherapy for individual patients.

ATP-Binding Cassette Transporters↗

PubMed2005

Interaction between the antidepressant-like behavioral effects of beta adrenergic agonists and the cyclic AMP PDE inhibitor rolipram in rats.

RATIONALE: Type 4 phosphodiesterase (PDE4) is critical for hydrolysis of cAMP formed by stimulation of beta adrenergic receptors. However, it is not known if PDE4 is associated with beta adrenergic receptors in the mediation of antidepressant-like effects. OBJECTIVE: The aim of the study is to determine the relationship between PDE4 and beta adrenergic receptor-mediated cAMP signaling in mediating antidepressant-like effects. METHODS: The effects of the PDE4 inhibitor rolipram, alone or combined with dobutamine or clenbuterol, selective beta-1 and beta-2 adrenergic agonists, respectively, on behavior were examined in rats under a differential reinforcement of low rate (DRL) schedule and rats trained to discriminate rolipram from vehicle. Their effects on cAMP in primary cultures of rat cerebral cortical neurons also were determined. RESULTS: Rolipram (0.01-0.3 mg/kg), dobutamine (1-30 mg/kg), and clenbuterol (0.03-0.3 mg/kg) dose-dependently produced antidepressant-like effects on DRL behavior, decreasing response rate and increasing reinforcement rate. The effects of beta adrenergic agonists were potentiated by rolipram. Isobolographic analysis revealed that rolipram enhanced the antidepressant-like effect of dobutamine additively and that of clenbuterol synergistically. Consistently, a combination of ineffective doses of rolipram (0.03 mg/kg) and dobutamine (3 mg/kg) or clenbuterol (0.03 mg/kg) completely substituted for the rolipram discrimination stimulus. Further, incubation with an ineffective concentration of clenbuterol, but not dobutamine, in the presence of a subeffective concentration of rolipram, significantly increased cAMP in cultured cortical neurons. CONCLUSIONS: PDE4 plays an important role in regulating cAMP signaling by either beta-1 or beta-2 adrenergic receptors that mediate antidepressant-like actions; beta-2 adrenergic receptor-mediated cAMP signaling appears more responsive than beta-1 cAMP signaling to PDE4 inhibition.

3',5'-Cyclic-AMP Phosphodiesterases↗