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J Kwong

Publications and source records attributed to J Kwong.

At least 19 recordsLinked to original sources
PubMed2006

Simultaneous measurement of ionization and scintillation from nuclear recoils in liquid xenon for a dark matter experiment.

We report the first measurements of the absolute ionization yield of nuclear recoils in liquid xenon, as a function of energy and electric field. Independent experiments were carried out with two dual-phase time-projection chamber prototypes, developed for the XENON dark matter project. We find that the charge yield increases with decreasing recoil energy, and exhibits only a weak field dependence. These results are the first unambiguous demonstration of the capability of dual-phase xenon detectors to discriminate between electron and nuclear recoils down to 20 keV, a key requirement for a sensitive dark matter search.

Journal Article↗
PubMed2006

Cutaneous immune activity varies with physiological state in female house sparrows (Passer domesticus).

Many vertebrates show seasonality in immune defenses, perhaps because of trade-offs with other physiological processes. Trade-offs between reproduction and immune function have been well studied, but how other life cycle events such as molt affect immune function remains unclear. Here, we hypothesize that one possible explanation is that accumulative dissociated processes (e.g., resource deficits generated over the long term by physiological processes) can have delayed effects on immune activity. To test this hypothesis, we compared cutaneous immune responses in groups of captive female house sparrows (Passer domesticus) photoperiodically induced into six different life cycle stages. We predicted that if delayed trade-offs occur, immune activity would be reduced after a mature life state was reached (e.g., postmolt) and not just compromised when other tissues were actively growing (instantaneous trade-off). We found evidence for both types of trade-offs: immune responses were weakest in sparrows that had just completed postnuptial molt, but they were also weak in birds growing reproductive tissues or feathers. Birds in mature reproductive states or light molt had strong immune responses comparable with birds in a nonbreeding/nonmolting state. Altogether, our results indicate that immune activity in female house sparrows can be influenced by both instantaneous and delayed trade-offs.

Animals↗
PubMed2001

High frequency of promoter hypermethylation of RASSF1A in nasopharyngeal carcinoma.

We have investigated the genetic and epigenetic changes of a newly isolated tumor suppressor gene on 3p21.3, RASSF1A, in nasopharyngeal carcinoma (NPC). Four xenografts, four cell lines and 21 primary tumors were examined. Promoter hypermethylation of the 5'CpG island of RASSF1A was detected in 4 of 4 (100%) xenografts, in 3 of 4 (75%) cell lines, and in 14 of 21 (66.7%) primary tumors but not in the normal nasopharyngeal epithelia. Mutations were found in 2 of 21 (9.5%) primary tumors. In the cell lines and xenografts with extensive methylation, no RASSF1A gene expression was found. After treatment with 5'-aza-2'deoxycytidine, reexpression and demethylation of the RASSF1A gene were detected in a NPC cell line. These findings suggest that promoter hypermethylation may participate in the transcriptional inactivation of the RASSF1A gene in NPC. The high incidence of RASSF1A alterations suggest that it is the critical target gene on chromosome 3p21.3 involved in the development of NPC.

Chromosomes, Human, Pair 3↗
PubMed2000

PSP94 (or beta-microseminoprotein) is a secretory protein specifically expressed and synthesized in the lateral lobe of the rat prostate .

BACKGROUND: Prostatic secretory protein of 94 amino acids (PSP94), also called beta-microseminoprotein, is a small, nonglycosylated protein, rich in cysteine residues. It was first isolated as a major protein from human seminal plasma. Subsequently, its homologous proteins were identified, and their cDNAs or genes have been cloned in primates, pigs, and rodents. METHODS: The present study investigated the expression pattern of PSP94 in the normal Noble rat prostate gland by nonradioactive in situ hybridization, Northern blotting, RT-PCR, Western blotting, and immunohistochemistry. Its expression in the mouse prostate gland was also examined by in situ hybridization. RESULTS: The results of in situ hybridization, and Northern and Western blot analyses, showed that the expression of rat PSP94 was prostate-specific. It was highly expressed in the lateral prostatic lobe, moderate in the dorsal lobe, weak in the coagulating gland, and negative in the ventral lobe and seminal vesicle. Its specific expression in the rat prostate gland was further confirmed by RT-PCR analysis of prostatic and nonprostatic organ tissues. Its mRNA transcripts were not detected in the urinary, digestive, and respiratory tracts, male and female reproductive organs, muscles, brain, and kidney. Its molecular mass was estimated to be 14.5 kDa by Western blotting. Similar prostate-specific expression of PSP94 was also observed by in situ hybridization in the lateral lobe, but not in the dorsal and ventral lobe, of the mouse prostate gland. CONCLUSIONS: Rat PSP94 is a major secretory protein highly expressed and synthesized by the lateral lobe of both rat and mouse prostate glands, and moderately expressed in the dorsal lobe of the rat prostate gland.

Animals↗
PubMed2000

Problem and probable pathological gambling: considerations from a community survey.

OBJECTIVE: To investigate the nature and extent of gambling problems in a region of Canada in which legalized gambling activities were expanded during the 1990s. METHOD: A standardized telephone interview was conducted with a random sample of 738 community-dwelling adults (response rate 74%) in Winnipeg, Manitoba. RESULTS: According to traditional classification criteria, the lifetime prevalence of "probable pathological gambling" was 2.6%. A further 3.0% of the sample met criteria for traditionally defined "problem gambling," and evidence suggests that both types of gamblers share several characteristics. Social or recreational gamblers significantly differed on several variables from individuals who reported gambling problems. CONCLUSIONS: The 2.6% prevalence figure is the highest yet reported in a Canadian epidemiological survey and was obtained in a region that developed a more liberal attitude toward gambling in the 1990s. Further, a continuum of severity was demonstrated by scores on the South Oaks Gambling Screen (SOGS), and a clear and consistent distinction between problem and probable pathological gambling was not apparent. Frequenting casinos and using video poker and slot machines, rather than buying lottery tickets, distinguishes problem or pathological gamblers from recreational gamblers.

Adult↗
PubMed2000

A comparative study of hormonal regulation of three secretory proteins (prostatic secretory protein-PSP94, probasin, and seminal vesicle secretion II) in rat lateral prostate.

The rat dorsolateral prostate secretes several major known proteins, although their physiological and reproductive functions are largely undefined. In the present study we examined and compared the in vivo hormonal regulation of the messenger RNA (mRNA) expression of three major secretory proteins, including prostatic secretory protein of 94 amino acids (PSP94 or beta-microseminoprotein), probasin, and seminal vesicle secretion II (SVSII), in long-term castrated lateral prostates (LP) by in situ hybridization and semiquantitative RT-PCR. The protein levels of PSP94 in the castrated LPs were also examined by Western blotting. PSP94 is a small protein newly isolated from the rat prostate gland and demonstrates highly specific expression in the LP. The results of in situ hybridization showed that PSP94, probasin, and SVSII were highly expressed in the intact LP. The hybridization signals of probasin and PSP94 disappeared in the 60-day postcastrated LPs, whereas the signals of SVSII dropped sharply in the 14-day postcastrated LPs. Similar patterns of decreasing mRNA levels of the three proteins in the castrated LPs were observed by RT-PCR analysis. Their mRNA transcripts were restored to normal levels after replacement with testosterone. The results indicate that these secretory proteins are all under androgen regulation in the rat LP. Interestingly, we also observed that their degrees of sensitivity or responsiveness to androgen withdrawal are different. Their mRNA levels dropped in response to duration of castration in the following decreasing order: SVSII, PSP94, and probasin. Besides androgen [dihydrotestosterone (DHT)], we also examined the effects of glucocorticoid [dexamethasone (DEX)], progestin [medroxyprogesterone acetate (MPA)], and zinc on their gene expressions in castrated LPs. We observed that the mRNA transcripts of both PSP94 and probasin were increased after treatments with DHT, DEX, and MPA, suggesting that these two proteins could also be regulated by glucocorticoid and progestin. In contrast with probasin, PSP94 and SVSII were not induced by ZnSO4 treatment. On the other hand, SVSII expression was only increased significantly by DHT and moderately by MPA, but not by DEX, suggesting that SVSII is under strict control by androgen.

Androgen-Binding Protein↗
PubMed2000

Hrs interacts with SNAP-25 and regulates Ca(2+)-dependent exocytosis.

Synaptosome-associated protein of 25 kDa (SNAP-25) is a neuronal membrane protein essential for synaptic vesicle exocytosis. To investigate the mechanisms by which SNAP-25 mediates neurosecretion, we performed a search for proteins that interact with SNAP-25 using a yeast two-hybrid screen. Here, we report the isolation and characterization of a SNAP-25-interacting protein that is the rat homologue of mouse hepatocyte growth factor-regulated tyrosine kinase substrate (Hrs). Hrs specifically interacts with SNAP-25, but not SNAP-23/syndet. The association of Hrs and SNAP-25 is mediated via coiled-coil interactions. Using an Hrs-specific antibody, we have shown that Hrs is highly enriched in brain, where it codistributes with SNAP-25 in most brain regions. Subcellular fractionation studies demonstrate that in brain, Hrs exists in both cytosolic and membrane-associated pools. Studies using indirect immunofluorescence and confocal microscopy reveal that, in addition to early endosomes, Hrs is also localized to large dense-core secretory granules and synaptic-like microvesicles in nerve growth factor-differentiated PC12 cells. Moreover, overexpression of Hrs in PC12 cells inhibits Ca(2+)-dependent exocytosis. These results suggest that Hrs is involved in regulation of neurosecretion through interaction with SNAP-25.

Amino Acid Sequence↗
PubMed1999

Differential expression of PSP94 in rat prostate lobes as demonstrated by an antibody against recombinant GST-PSP94.

Prostate secretory protein (PSP94, 94 amino acids) is one of the most abundant proteins secreted from the prostate. Its biological role is unknown and still controversial, although it is assumed to have the potential to be a biomarker and a suppressor of prostate cancer. In order to establish an animal model to further elucidate its biological role, we expressed the mature form of rat PSP94 in Escherichia coli, using a glutathione S-transferase (GST) fusion expression vector; we generated a polyclonal rabbit antibody against the recombinant protein. The antibody specifically recognized recombinant rat PSP94 and cross-reacted only very weakly with its human homologue. Using the characterized anti-rat PSP94 antibody, we found that PSP94 was located primarily in rat prostate. Furthermore, PSP94 is present at different levels in different lobes of rat prostate, with significant levels detectable only in the lateral lobe (LP). In addition, the most abundant PSP94 expression was found in the prostate lobe secretions, and PSP94 levels in LP secretions were at least seven times higher than in secretions from the dorsal prostate (DP). The rat ventral prostate (VP) and other regions of the male accessory glands were found to be almost completely devoid of PSP94. Since most rat prostate dysplasia induced by steroid hormone treatment occurs only in dorsolateral prostate, prostate tissue-specific expression and the expression of PSP94 in dorsolateral, but not other, lobes of the prostate suggest a potential role in prostate targeting and prostate cancer development.

Animals↗
PubMed1999

Ultrastructural and biochemical observations on the early changes in apoptotic epithelial cells of the rat prostate induced by castration.

The present study describes the sequential ultrastructural changes in the apoptotic cells of the rat ventral and dorsal prostates during the early period of 1-3 days postcastration. The major morphological changes include: (1) condensation of heterochromatin along the nuclear envelope and fragmentation into crescent-shaped micronuclei; (2) formation of membrane-bound cytoplasmic spherical bodies, which contain various organelles and micronuclei, within the apoptotic cells; (3) formation of non-membrane-bound autolytic vacuoles by autolysis of cytoplasm; (4) focal rupture of outer mitochondrial membrane; and (5) phagocytosis of the fragmented cytoplasmic spherical bodies and apoptotic cells by macrophages. The occurrence of both cytoplasmic apoptotic bodies and autolytic vacuoles in apoptotic cells suggests that the cytoplasm of the apoptotic cells could be destroyed by different means. The responsiveness of different prostatic lobes to androgen withdrawal and the time course of the transitory apoptotic activity in different lobes were analyzed by counting the indices of the TUNEL-labeled apoptotic cells against the postcastration periods. The results showed that the ventral lobe responded more rapidly to castration than the lateral and dorsal lobes. The dorsal lobe was the slowest in response to castration among the three lobes. Analysis of protease activities by zymography has identified two Ca(2+)-independent proteases of apparent MW 20 and 24 kDa (expressed in both ventral and dorsolateral lobes), and one Ca(2+)-dependent protease of MW 66.5 kDa (expressed only in the dorsolateral lobe) which became activated at day 3 postcastration. Their expression patterns were different from that of CPP-3 in the castrated prostates, suggesting that the activated proteases were enzymes other than CPP-3. The association of their highest activities with the maximum apoptotic activity at day 3 postcastration and also their loss of activity at day 15 suggest that these protease activities might be related to apoptosis or glandular involution.

Animals↗
PubMed1999

cDNA, genomic cloning, and gene expression analysis of mouse PSP94 (prostate secretory protein of 94 amino acids).

The potential use of prostate secretory protein of 94 amino acids (PSP94) as a diagnostic biomarker or a therapeutic agent for prostate cancer has been reported. In order to establish an animal model to further elucidate on its biological role, we cloned the mouse PSP94 cDNA (approximately 500 bp) by reverse transcriptase-polymerase chain reaction (RT-PCR) and disclosed its genomic structure. The whole mouse PSP94 gene (approximately 23 kb) was amplified by long and accurate-PCR and also cloned by screening of a mouse embryo stem-cell genomic library. Computational and statistical analyses have demonstrated several highly conserved characteristics of PSP94 among different species. Comparison of PSP94 from human, two primates, pig, and rodents revealed that the most significant feature is that PSP94 is rich in cysteines (10% of the total sequence) and their positions are highly conserved. The three intron-four exon structure of the human PSP94 gene and the consensus sequence (....GT-intron-AG...) for mRNA splicing are also strongly conserved. A high divergence in cDNA sequence in the protein-coding region and also in the genomic sequence of PSP94 was also observed among these species. Comparing with alpha-globin, a typical evolutionally conserved gene, with the PSP94 gene, the rate of nonsynonymous changes per site per year (kN) is 2 to 6 times higher, indicating that PSP94 gene has been under far fewer evolutionary constraints than other genes and has a potential role as a species barrier in reproductive biology. In order to test this hypothesis, we investigated the gene expression of PSP94 and its tissue distribution in various rodent tissues by RT-PCR and in situ hybridization (ISH). Gene expression was found only in the prostate, suggesting that PSP94 is probably more tissue specific in the prostate of rodents than in mammals. The ISH analysis also revealed a prostate lobe-specific expression of the PSP94 gene in both mice and rats. It was strongly expressed in the lateral prostate, but the findings were negative in the dorsal and ventral lobe. Therefore, it is hypothesized that one of the primary functions of rodent PSP94, as a major prostate secretory protein, is related to reproductive biology.

Amino Acid Sequence↗
PubMed1996

The enteroinsular axis in dipeptidyl peptidase IV-negative rats.

Evidence has accumulated that the incretins glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1(7-36) amide) are degraded and rendered biologically inactive in plasma by the enzyme dipeptidyl peptidase IV (DPIV). A strain of Fischer rats lacking the DPIV enzyme were used in the current investigation as a model for examining the enteroinsular axis under conditions in which normal inactivation of GIP and GLP-1(7-36) does not occur. This was assessed by comparing GIP and GLP-1(7-36) responses following oral glucose in normal versus DPIV-deficient Fischer rats, and by comparing the insulinotropic potency of both peptides in the perfused pancreas of both groups. The insulin response to an oral glucose challenge was decreased slightly in DPIV-negative rats compared with control animals. Of the two incretins, the GIP response to oral glucose was reduced by 50% compared with controls, whereas GLP-1(7-36) release in response to glucose was unchanged. A decrease of 30% in the sensitivity of the perfused pancreas of DPIV-negative rats to GIP was observed, whereas the insulin response to GLP(7-36) was identical in both groups. Incubation of both peptides in plasma from DPIV-positive and -negative rats was performed to determine the effect of the presence or absence of DPIV on the insulinotropic activity of GLP-1(7-36) and GIP in the isolated perfused rat pancreas. Incubation in plasma from DPIV-positive rats resulted in a 65% decrease in insulinotropic activity of both incretins compared with incubation in plasma from DPIV-deficient rats. It was hypothesized that the reduced GIP response and decreased sensitivity of the pancreas to GIP are compensatory mechanisms that maintain insulin and glucose levels within a normal range despite abnormal degradation of GIP. An explanation of the lack of effect of the absence of DPIV on the GLP-1(7-36) response to oral glucose and insulinotropic action of this peptide must await further study.

Animals↗
PubMed1996

Proteasome complex as a potential cellular target of hepatitis B virus X protein.

Although the biological importance of hepatitis B virus X protein (HBX) in the life cycle of hepatitis B virus has been well established, the cellular and molecular basis of its function remains largely undefined. Despite the association of multiple activities with HBX, none of them appear to provide a unifying hypothesis regarding the true biological function of HBX. Identification and characterization of cellular targets of HBX remain an essential goal in the elucidation of the molecular mechanisms of HBX. Using the Saccharomyces cerevisiae two-hybrid system, we have identified and characterized a novel subunit of the proteasome complex (XAPC7) that interacts specifically with HBX. We also showed that HBX binds specifically to XAPC7 in vitro. Mutagenesis studies have defined the domains of interaction to be critical for the function of HBX. Furthermore, overexpression of XAPC7 appeared to activate transcription by itself and antisense expression of XAPC7 was able to block transactivation by HBX. Therefore, the proteasome complex is possibly a functional target of HBX in cells.

Amino Acid Sequence↗
PubMed1995

Identification of complement regulatory domains in human factor H.

Factor H, a regulator of complement activation, contains 20 short consensus repeat (SCR) domains common among the family of C3b/C4b-binding proteins. Chinese hamster ovary cells transfected with cDNA corresponding to the N-terminal tryptic fragment of factor H (containing SCR 1-5 and part of SCR 6) secreted protein with cofactor activity for factor I-dependent cleavage of C3b. A series of deletion mutants, each lacking one of the first five SCR, were constructed, and the supernatants of transfected Chinese hamster ovary cells were tested for cofactor activity. Supernatants of Chinese hamster ovary cells transfected with SCR 1, SCR 4, and SCR 5 deletion mutants retained cofactor function, although the SCR 1 deletion had reduced cofactor activity. Deletion of SCR 2 or 3 totally abolished cofactor activity. Expression and functional analysis of SCR units 1-3, 2-3, and 2-4 demonstrated that the SCR 1-3 unit is sufficient for cofactor activity, but SCR 1-4 is required for full activity. For assays involving cell protection, a construct linking SCR 1-5 to the glycosyl-phosphatidylinositol anchor of decay-accelerating factor was prepared, and stable transfectants were obtained. These cells were protected against complement-mediated cytotoxicity, similarly to decay-accelerating factor- and membrane cofactor protein-transfected cells. These studies define the complement regulatory domains in factor H and suggest that the general complement functional unit for C3 convertase regulation involves three or four consecutive SCR units.

Animals↗
PubMed1995

Amino-terminal palmitate or polybasic domain can provide required second signal to myristate for membrane binding of p56lck.

Recent work has shown that several members of the src family of protein tyrosine kinases (PTKs) are modified by palmitoylation, including p56lck and p59fyn but not p60src. Mapping of the sites of palmitoylation in p56lck identified cys3 as the major site and cys5 as a minor site of palmitoylation. A non-palmitoylated p56lck(cys3,5-->ser) mutant was localized exclusively in the cytoplasm despite the presence of amino-terminal myristoylation, thus indicating that palmitoylation of p56lck was necessary for membrane binding. The addition of a domain of six lysine residues to a non-palmitoylated p56lck mutant was sufficient to re-establish membrane binding but not to target the non-palmitoylated p56lck to caveolae. These results establish that two signals, myristoylation plus either palmitoylation or a polybasic domain, are necessary for membrane binding of src family PTKs.

Amino Acid Sequence↗
PubMed1994

Cysteine3 of Src family protein tyrosine kinase determines palmitoylation and localization in caveolae.

Recent work has demonstrated that p56lck, a member of the Src family of protein tyrosine kinases (PTKs), is modified by palmitoylation of a cysteine residue(s) within the first 10 amino acids of the protein (in addition to amino-terminal myristoylation that is a common modification of the Src family of PTKs). This is now extended to three other members of this family by showing incorporation of [3H]palmitate into p59fyn, p55fgr, and p56hck, but not into p60src. The [3H]palmitate was released by treatment with neutral hydroxylamine, indicating a thioester linkage to the protein. Individual replacement of the two cysteine residues within the first 10 amino acids of p59fyn and p56lck with serine indicated that Cys3 was the major determinant of palmitoylation, as well as association of the PTK with glycosyl-phosphatidylinositol-anchored proteins. Introduction of Cys3 into p60src led to its palmitoylation. p59fyn but not p60src partitioned into Triton-insoluble complexes that contain caveolae, microinvaginations of the plasma membrane. Mapping of the requirement for partitioning into caveolae demonstrated that the amino-terminal sequence Met-Gly-Cys is both necessary and sufficient within the context of a Src family PTK to confer localization into caveolae. Palmitoylation of this motif in p59fyn also modestly increased its overall avidity for membranes. These results highlight the role of the amino-terminal motif Met-Gly-Cys in determining the structure and properties of members of the Src family of PTKs.

Acylation↗
PubMed1993

Palmitylation of an amino-terminal cysteine motif of protein tyrosine kinases p56lck and p59fyn mediates interaction with glycosyl-phosphatidylinositol-anchored proteins.

Cross-linking of glycosyl-phosphatidylinositol (GPI)-anchored membrane proteins on T cells can trigger cell activation. We and others have shown an association between GPI-anchored proteins and the protein tyrosine kinases (PTKs) p56lck and p59fyn, suggesting a pathway for signaling through GPI-anchored proteins. Studies of decay-accelerating factor (DAF) or CD59 in either the C32 cell line or the HeLa cell line transfected with PTK cDNA demonstrated that the GPI-anchored proteins associated noncovalently with p56lck and p59fyn but not with p60src. Nonmyristylated versions of p56lck and p59fyn also failed to associate with the GPI-anchored proteins. Mutational analysis of the PTK demonstrated that the association with the GPI-anchored proteins mapped to the unique amino-terminal domains of the PTK. A chimeric PTK consisting of the 10 amino-terminal residues of p56lck or p59fyn replacing the corresponding amino acids in p60src was sufficient for association with DAF, but the converse constructs containing the first 10 amino acids of p60src plus the remainder of p56lck or p59fyn did not associate with DAF. Mutation of cysteine to serine at positions 3 and 6 in p59fyn or positions 3 and 5 in p56lck abolished the association of these kinases with DAF. Mutation of serine to cysteine at positions 3 and 6 in p60src conferred on p60src the ability to associate with DAF. Direct labeling with [3H]palmitate demonstrated palmitylation of this amino-terminal cysteine motif in p56lck. Thus, palmitylation of the amino-terminal cysteine residue(s) together with myristylation of the amino-terminal glycine residue defines important motifs for the association of PTKs with GPI-anchored proteins.

Amino Acid Sequence↗
PubMed1992

Signal transduction through decay-accelerating factor. Interaction of glycosyl-phosphatidylinositol anchor and protein tyrosine kinases p56lck and p59fyn 1.

Decay-accelerating factor (DAF or CD55) is a 70-kDa glycosyl-phosphatidylinositol (GPI)-anchored protein that protects cells from complement-mediated lysis by either preventing the formation of or dissociating C3 convertases. Cross-linking of DAF on human peripheral T cells by polyclonal antibodies has previously been reported to lead to lymphocyte proliferation. Two mAb, both mapping to the third short consensus repeat region of DAF, were able to trigger proliferation of human peripheral T cells. To determine the role of the GPI anchor in cell activation, we transfected EL-4 murine thymoma cells with cDNA encoding either DAF or a transmembrane form of DAF (DAF-TM). The DAF-transfected cells were able to transduce late activation events as evidenced by IL-2 production, whereas DAF-TM transfected cells were unable to do so. The GPI-anchored DAF was able to transduce early activation events leading to the tyrosine phosphorylation of a 40-kDa protein and several proteins in the 85-95 kDa range--an event absent in DAF-TM-transfected cells. Furthermore, anti-DAF immunoprecipitates of DAF-transfected cells contain tyrosine kinase activity leading to the phosphorylation of 40-, 56-60-, and 85-kDa proteins, whereas anti-DAF immunoprecipitates of DAF-TM-transfected cells did not have an associated kinase activity. Both p56lck and p59fyn were associated with DAF in DAF-transfected EL-4 cells. In HeLa cells transfected with fyn, DAF associated with p59fyn. This complex of DAF with src family protein tyrosine kinases requires the GPI anchor and suggests a pathway for signaling through GPI-anchored membrane proteins.

Antigens, CD↗