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Biomedical subjects

A A Sahin

Publications and source records attributed to A A Sahin.

At least 19 recordsLinked to original sources
PubMed2002

Recommendations for sentinel lymph node processing in breast cancer.

The status of the sentinel lymph node (SLN) has been shown to accurately reflect the presence or absence of metastases in the axilla in patients with breast cancer. This study was designed to determine the optimal protocol for SLN processing. A total of 173 SLNs from 96 breast cancer patients who had successful SLN localization and underwent completion axillary node dissection were identified. All SLNs were negative for metastases by initial routine histologic evaluation. The nodes were submitted in a total of 300 blocks. Each block was serially sectioned to produce 10 levels. Pan-cytokeratin stain was performed on levels 3 and 8. All other levels were stained with hematoxylin and eosin. Metastases were identified in 22 SLNs from 19 patients by examining all 10 levels. The first two hematoxylin and eosin- or the first cytokeratin-stained levels were positive for metastases in 21 (95.5%) of the 22 positive SLNs. Two additional hematoxylin and eosin-stained and one cytokeratin-stained levels of each SLN correctly identified the status of the node in 94 (97.9%) of 96 patients. Therefore, we recommend that after an initial hematoxylin and eosin-stained section, two additional hematoxylin and eosin-stained sections and one cytokeratin-stained section should be evaluated.

Adult↗
PubMed2001

Down-regulated melanoma differentiation associated gene (mda-7) expression in human melanomas.

The melanoma differentiation associated gene-7 (mda-7) has a potential inhibitory role in melanoma progression, although the mechanisms underlying this effect are still unknown. mda-7 mRNA has been found to be present at higher levels in cultured normal melanocytes compared with metastatic melanoma cell lines. Furthermore, levels of mda-7 message have shown an inverse correlation with melanoma progression in human tumor samples, suggesting that mda-7 may be a novel tumor suppressor gene. We have designed this study to investigate MDA-7 protein expression in different stages of melanoma progression and to examine its antiproliferative effects in vitro. Our data demonstrate that MDA-7 protein can be found in normal melanocytes and early stage melanomas. It is also observed in smooth muscle cells in the skin. However, in keeping with a possible role as a tumor suppressor, MDA-7 expression is decreased in more advanced melanomas, with nearly undetectable levels in metastatic disease. We also investigated antitumor effects of overexpressed MDA-7 on human melanoma cells in vitro. Our results demonstrate that Ad-mda-7 induces apoptosis and G2/M cell cycle arrest in melanoma cells, but not in normal human melanocytes.

Apoptosis↗
PubMed2001

A case-control study of unilateral and bilateral breast carcinoma patients.

BACKGROUND: Women with unilateral breast carcinoma are at increased risk for developing contralateral disease. The clinical significance of bilateral breast carcinoma has not been fully defined, and the subset of patients who may benefit from medical or surgical risk-reduction intervention has not yet been characterized. The purpose of this study was to evaluate risk factors and outcomes for bilateral breast carcinoma. METHODS: A subject group of 70 bilateral breast carcinoma patients (62% metachronous) was matched by age and survival interval with a control group of 70 unilateral breast carcinoma patients. Median follow-up was 103 months. RESULTS: Eighty-two percent of the unilateral patients and 80% of the bilateral patients had Stage I or II disease at diagnosis. Median age at presentation was 53 years. In the bilateral group, the contralateral cancer was diagnosed at the same or earlier stage than the first cancer in 87% of cases. Bilateral patients were significantly more likely to have multicentric disease and to have a positive family history for breast carcinoma compared with the unilateral group. There were no significant differences regarding history of exogenous hormone exposure, lobular histology, hormone-receptor status, or HER-2/neu expression. Five-year disease-free survival was 94% for the unilateral breast carcinoma patients and 91% for the bilateral breast carcinoma patients (P = 0.16). CONCLUSIONS: Survival for patients with bilateral breast carcinoma is similar to that of patients with unilateral disease; however, prophylactic risk-reduction intervention for the contralateral breast should be considered in patients who have multicentric unilateral disease or a positive family history for breast carcinoma.

Adult↗
PubMed2001

Expression of erbB/HER receptors, heregulin and P38 in primary breast cancer using quantitative immunohistochemistry.

The purpose of this study was to investigate the frequency of expression of the erbB/HER family of growth factor receptors, their ligand heregulin, and the two different signaling pathways p38 and mitogen-activated protein kinase (MAPK), as well as the status of HER-2 phosphorylation in tumor specimens from patients with primary breast cancer. The level of expression of these proteins was measured by quantitative immunohistochemistry combined with microscope-based image analysis in paraffin-embedded breast cancer tissue from 35 patients. The frequency of expression was: EGFR (51%), HER-2 (54%), P-HER-2 (48%), HER-3 (48%), HER-4 (57%), heregulin (48%), p38 (17%), MAPK (48%). There was evidence of associations among the coexpression of heregulin, EGFR, HER-2, and HER-3. Also, there was evidence of a positive association between P-MAPK and HER-4. HER-3 was expressed at high levels in patients younger than 50 years of age. There was a trend for expression of higher levels of HER-4 in tumors larger than 2 cm. The expression of EGFR, HER-2, heregulin, p38 and MAPK was independent of age, tumor size, number of lymph nodes involved or hormone receptor status. The HER family of growth factor receptors appear to be regulated independently in invasive breast cancer. Assessing the expression of multiple tumor markers by quantitative immuno-histochemistry is feasible. Further research is needed to determine the prognostic and predictive roles of the various associations between HER receptors, their ligands and signal transduction molecules in patients with early-stage breast cancer.

Breast Neoplasms↗
PubMed2001

Computerized image analysis of Ki-67 in ductal breast carcinoma in situ.

OBJECTIVE: To develop and determine the staining protocols and computerized image analysis methods that are the most effective combination for performing quantitative analysis of Ki-67. STUDY DESIGN: We compared conventional bright-field light microscopy and refractive optical enhancement methods in combination with various immunodetection and filter enhancement methods, including immunogold in combination with epipolarization refractive optics and enzymatic conversion of chromogenic substrates in combination with optical filter enhancement. Initial Ki-67 tests were performed on lymph node tissues and cultured human breast cells and then applied to 200 ductal carcinoma in situ (DCIS) samples. DCIS acini were digitally acquired, and a region of interest was manually outlined in each one with a digital stylus to include only the cellular component; then the Ki-67 staining index was quantified by segmentation analysis. RESULTS: Although combining epipolarization analysis with immunohistogold staining was the most sensitive detection method, nonspecific binding was too high. The streptavidin-horseradish-peroxidase enzymatic conversion of 3,3'-diaminobenzidine (DAB) in combination with optical enhancement filters was the most effective method tested. Ki-67 stain was associated with dense fibrillar structures of the nucleoli in the less intensely staining nuclei and was most intense in paired nuclei. CONCLUSION: The method of measuring Ki-67 expression by DAB staining combined with optical enhancement filters and quantification via computer-assisted image analysis techniques produced objective and reproducible results. As such, this method can offer (1) less intraobserver and interobserver variability, (2) a digital archival record, and (3) a baseline for digital exchange of information between studies.

Antibodies, Monoclonal↗
PubMed2001

HER-2/neu overexpression as a poor prognostic factor for patients with metastatic breast cancer undergoing high-dose chemotherapy with autologous stem cell transplantation.

PURPOSE: High-dose chemotherapy with autologous stem cell transplantation (HDCT) produces a high tumor response rate for patients with metastatic breast cancer and have 20% long-term progression-free survival. Overexpression of HER-2/neu oncoprotein predicts outcome in patients with breast cancer given standard-dose chemotherapy. Therefore, we evaluated whether the HER-2/neu overexpression in the primary tumor predicts clinical outcome in patients with metastatic breast cancer given HDCT. EXPERIMENTAL DESIGN: A total of 236 patients were given standard-dose induction chemotherapy followed by stem cell collection; high-dose chemotherapy with cyclophosphamide, thiotepa, and carmustine; and stem cell infusion. HER-2/neu expression was assessed by immunostaining with anti-HER-2/neu e2-4001 monoclonal antibody in 63 patients. RESULTS: Clinical characteristics and survival were similar for patients with known and unknown HER-2/neu status. HER-2/neu was overexpressed in 22 of 63 tumors (35%). There was some tendency for HER-2/neu overexpression to be associated with the absence of estrogen or progesterone receptors. In considering the association of HER-2/neu expression with patient outcomes, HER-2/neu overexpression was associated with generally shorter overall survival (P = 0.02) and progression-free survival (P < 0.01), and this association persisted to a lesser extent after adjustment for differences in important prognostic factors between the two groups. CONCLUSION: We conclude that HER-2/neu overexpression may represent an additional prognostic factor for patients with metastatic breast cancer who undergo HDCT.

Antibodies, Monoclonal↗
PubMed2000

Colitis associated with docetaxel-based chemotherapy in patients with metastatic breast cancer.

BACKGROUND: Docetaxel and vinorelbine as combined treatment for metastatic breast cancer can have the dose-limiting toxic effects of mucositis and neutropenic fever. We report unexpected ischaemic colitis in six patients associated with docetaxel-based therapy, three of whom were treated in a phase I study designed to establish the maximum tolerated dose of this combination with the prophylactic use of granulocyte-colony-stimulating factor. METHODS: Between August, 1997, and December, 1998, 14 patients with metastatic breast cancer were treated with vinorelbine, docetaxel, and granulocyte-colony-stimulating factor in a phase I study. Three patients developed colitis similar to that seen in typhlitis. Three additional patients were identified during scheduled review of toxic effects in patients participating in clinical trials involving docetaxel. FINDINGS: Three patients on combined vinorelbine and docetaxel developed colitis-like symptoms. Two patients died, one from necrotic bowel and the other from neutropenic fever and colitis. Two of the patients presented on day 7 and day 8 of chemotherapy, respectively, with neutropenic fever and abdominal pain; the third patient developed neutropenia without fever and abdominal pain on day 8. The other three patients were treated with docetaxel, docetaxel and pamidronate disodium, or docetaxel and cyclophosphamide. All three patients presented with abdominal pain on days 10, 5, and 4, respectively. One had non-neutropenic fever, another had neutropenic fever, and the third was afebrile and non-neutropenic at the time of presentation with abdominal pain. Three patients had blood in their diarrhoea, abdominal tenderness, or both. Computed tomography of the abdomen and pelvis showed features of colitis in three patients. INTERPRETATION: This serious complication may result from the use of docetaxel and may be exacerbated by its combination with vinorelbine. Study of hospital-based patients treated with taxane-based chemotherapy is underway to find out the frequency of such complications.

Aged↗
PubMed2000

Elevated expression of hepatic proliferative markers during early hepatocarcinogenesis in hepatitis-B virus transgenic mice lacking mdr1a-encoded P-glycoprotein.

Recent studies have shown that expression levels of the multidrug resistance gene MDR1, which encodes the drug transporter P-glycoprotein, correlate with prognostic outcomes of certain tumor types. These findings suggest that expression of MDR1 may affect tumor behaviors. To address this issue further, we investigated the expression of mdr1a, a human MDR1 homolog, on the development of hepatocellular carcinoma in a transgenic mouse model carrying the liver-targeted expression of human hepatitis-B virus (HBV) surface antigen. The pathogenetic program was compared in HBV mice carrying either mdr1a(+/+) or mdr1a(-/-). We found that the expressions of proliferative activity markers, Ki67 nuclear antigen, and proliferating cell nuclear antigen were elevated in mdr1a(-/-) mice younger than 10 wk in comparison with those in the same age group of wild-type animals. Replication in the hepatic population as determined by bromodeoxyuridine incorporation tended to support observation that mdr1a(-/-) mice exhibited elevated labeling indices in this age group. Moreover, histologic staining and flow-cytometric analysis showed that the mdr1a(-/-) animals exhibited a higher cell population with polyploidy than did the mdr1a(+/+) counterparts of the same age. However, no significant differences in the expression of the liver-injury markers serum alanine transaminase and aspartate transaminase were observed. Although our results showed that absence of mdr1a expression is correlated with modest enhanced proliferative characteristics in the livers at stage before the development of hepatocellular carcinoma, the overall life spans between these two strains of mice were not significantly different. The implication of these findings to the role of P-glycoprotein in tumor development and cancer chemotherapy is discussed.

ATP Binding Cassette Transporter, Subfamily B↗
PubMed2000

Role of specimen radiography in patients treated with skin-sparing mastectomy for ductal carcinoma in situ of the breast.

BACKGROUND: Specimen radiography is an important part of breast conservation surgery for ductal carcinoma in situ (DCIS). The objective of this study was to determine whether mastectomy specimen radiography could help in obtaining negative resection margins in patients with DCIS undergoing skin-sparing mastectomy (SSM) with immediate breast reconstruction (IBR). METHODS: Of 95 patients treated at our institution with SSM and IBR for DCIS, 35 had specimen radiography. The mastectomy specimen was first examined grossly and then inked, serially sectioned, and sent for radiographic assessment. Tissue slices containing calcifications were identified for pathologic evaluation. Additional tissue was excised if tumor was found near the inked margins or if calcifications were found near the radiographic margins. RESULTS: Of the 35 patients who had specimen radiography, the radiographic margins were free of calcifications in 30 patients (86%); of these patients, the margins on the final histologic examination were free of tumor in 27 and within 1 mm in 3. The other five patients (14%) had calcifications close to the radiographic margin; four underwent an intraoperative re-excision, but the margin for one of those four patients was still positive on final histologic examination. Margins were found to be negative by both mastectomy specimen radiography and histology in 77% of the patients. Of the 95 patients with DCIS, three patients (3%), none of whom had specimen radiography, developed local recurrences. One of these was successfully re-treated, one died as a result of synchronous distant metastases, and one was lost to follow-up. At a median follow-up time of 3.7 years, 93 patients (98%) were alive and free of disease. CONCLUSIONS: Intraoperative radiography of mastectomy specimens may be useful for assessing margin status and for identifying the location of microcalcifications within tissue slices.

Adult↗
PubMed2000

Ductal carcinoma-in-situ: long-term results of breast-conserving therapy.

BACKGROUND: The role of breast-conserving therapy (BCT) in the management of ductal carcinoma-in-situ (DCIS) is controversial because of reported high recurrence rates. We reviewed our experience to determine whether the rate and pattern of locoregional recurrence after BCT were similar in patients with DCIS and patients with early-stage (T1) invasive breast tumors and whether local recurrence affected survival. METHODS: Between 1973 and 1994, 87 patients with DCIS alone, 22 patients with DCIS with microinvasion (DCIS-M), and 646 patients with invasive breast cancer 2 cm or smaller in diameter were treated with BCT (wide local excision with radiotherapy) at The University of Texas M. D. Anderson Cancer Center. Survival was calculated by the Kaplan-Meier method. The median follow-up times were 11 years for patients with DCIS alone, 12 years for patients with DCIS-M, and 8 years for patients with invasive breast cancer. RESULTS: Eleven (13%) of 87 patients with DCIS and 5 (23%) of 22 patients with DCIS-M had developed locoregional recurrences at follow-up. Two patients with DCIS with locoregional recurrence died of breast cancer. Of the 646 patients with invasive breast cancer, 56 (9%) had a locoregional recurrence, and 16 (2%) died of breast cancer. The median time to locoregional recurrence was significantly longer in patients with DCIS or DCIS-M (9-10 years) than patients with invasive tumors (5 years). CONCLUSIONS: DCIS is a favorable disease with an excellent long-term survival. The locoregional recurrence rate in patients with DCIS treated with BCT is similar to that in patients with early-stage invasive breast cancer treated with BCT, but time to locoregional recurrence is significantly longer in patients with DCIS. In patients with DCIS treated with BCT, intense surveillance for locoregional recurrence needs to be maintained for the patient's lifetime.

Adult↗
PubMed2000

In vivo expression of the novel CXC chemokine BRAK in normal and cancerous human tissue.

Using differential display, we cloned a gene with reduced expression in short-term explants of head and neck squamous cell carcinoma (HNSCC) tumors compared to cultured normal oral epithelial cells. The differentially expressed gene was identical to the recently cloned CXC chemokine BRAK, which is ubiquitously expressed in normal tissue extracts but is absent from many tumor cell lines in vitro. To define the cell populations expressing BRAK in vivo, in situ mRNA hybridization was performed on normal and cancerous tissues from six different histological sites. The predominant normal cell type constitutively expressing BRAK in vivo was squamous epithelium. Expression in tumors was heterogeneous, with the majority of HNSCCs and some cervical squamous cell carcinomas (SCCs) showing loss of BRAK mRNA. Although absent in unstimulated peripheral blood mononuclear cells, high levels of BRAK were consistently found in infiltrating inflammatory cells (with lymphocyte morphology) in nearly all cancers examined. Furthermore, BRAK expression was demonstrated in B cells and monocytes, after stimulation of peripheral blood mononuclear cells with lipopolysaccharide. This study demonstrates for the first time up-regulation of BRAK mRNA by inflammatory cells in the tumor microenvironment and lost expression from certain cancers in vivo. The data suggest that BRAK may have a role in host-tumor interactions.

Amino Acid Sequence↗
PubMed2000

Fascin, an actin-bundling protein associated with cell motility, is upregulated in hormone receptor negative breast cancer.

Loss of hormone receptor (HR) status in breast carcinomas is associated with increased tumour cell motility and invasiveness. In an immunohistological study of 58 primary breast cancers, oestrogen (ER) and progesterone (PR) receptor levels were inversely correlated with the expression of fascin, an actin-bundling protein associated with cell motility (P< 0.0001 and P = 0.0019, respectively). In addition, fascin was preferentially expressed in non-diploid tumours (P = 0.03). In summary, the upregulation of fascin in HR-negative breast cancers may contribute to their more aggressive behaviour.

Actins↗
PubMed2000

Identification and evaluation of axillary sentinel lymph nodes in patients with breast carcinoma treated with neoadjuvant chemotherapy.

Sentinel lymph node (SLN) biopsy has been shown to predict axillary metastases accurately in early stage breast cancer. Some patients with locally advanced breast cancer receive preoperative (neoadjuvant) chemotherapy, which may alter lymphatic drainage and lymph node structure. In this study, we examined the feasibility and accuracy of SLN mapping in these patients and whether serial sectioning and keratin immunohistochemical (IHC) staining would improve the identification of metastases in lymph nodes with chemotherapy-induced changes. Thirty-eight patients with stage II or III breast cancer treated with neoadjuvant chemotherapy were included. In all patients, SLN biopsy was attempted, and immediately afterward, axillary lymph node dissection was performed. If the result of the SLN biopsy was negative on initial hematoxylin and eosin-stained sections, all axillary nodes were examined with three additional hematoxylin and eosin sections and one keratin IHC stain. SLNs were identified in 31 (82%) of 38 patients. The SLN accurately predicted axillary status in 28 (90%) of 31 patients (three false negatives). On examination of the original hematoxylin and eosin-stained sections, 20 patients were found to have tumor-free SLNs. With the additional sections, 4 (20%) of these 20 patients were found to have occult lymph node metastases. These metastatic foci were seen on the hematoxylin and eosin staining and keratin IHC staining. Our findings indicate that lymph node mapping in patients with breast cancer treated with neoadjuvant chemotherapy can identify the SLN, and SLN biopsy in this group accurately predicts axillary nodal status in most patients. Furthermore, serial sectioning and IHC staining aid in the identification of occult micrometastases in lymph nodes with chemotherapy-induced changes.

Adenocarcinoma, Mucinous↗
PubMed2000

Biologic and clinical significance of HER-2/neu (cerbB-2) in breast cancer.

HER-2/neu (also known as c-erbB-2) oncogene is a member of the epidermal growth factor receptor family and its amplification is one of the most common genetic alterations associated with human breast cancer. Preclinical studies have suggested that HER-2/neu overexpression enhances metastatic potential of breast cancer cells. Although some discrepancies exist in clinical studies, in general, HER-2/neu amplification is found to be associated with more aggressive clinicopathologic features. HER-2/neu amplification is also associated with drug resistance or sensitivity to specific chemotherapy and hormonal therapy regimens. Advances in breast cancer therapies in recent years have moved towards the development of tumor-specific targeted therapies. Monoclonal antibodies directed against HER-2/neu have been developed and used in clinical practice. These developments necessitate a reliable assay for assessment of HER-2/neu. This article is a review of biologic and clinical significance of HER-2/neu and summarizes HER-2/neu detection methods.

Animals↗
PubMed2000

HER-2/neu gene amplification compared with HER-2/neu protein overexpression and interobserver reproducibility in invasive breast carcinoma.

We compared the detection of HER-2/neu gene amplification by fluorescence in situ hybridization (FISH) with detection of HER-2/neu protein overexpression by immunohistochemistry using 2 antibodies on 100 archival invasive breast carcinomas. Protein overexpression for each marker was scored independently by 4 pathologists using standardized criteria, and consensus was compared with results obtained from gene amplification. The concordance rate between FISH and immunohistochemistry was 76% for e2-4001 and 91% for the HercepTest. Of the 37 cases positive by e2-4001, 21 demonstrated no gene amplification; 7 of 24 cases positive by the HercepTest demonstrated no gene amplification. However, 1 of 61 cases negative by e2-4001 showed gene amplification; none of the cases negative by the HercepTest showed amplification. The predictive values of gene amplification based on 0-1+, 2+, and 3+ immunohistochemical staining were best for cases scored as 3+ (75% for e2-4001 and 89% for the HercepTest). Complete agreement among observers for immunohistochemical scoring of e2-4001 and the HercepTest was achieved in 75 and 85 cases, respectively. The pairwise kappa agreement values were substantial for e2-4001 and substantial to almost perfect for the HercepTest. Immunohistochemical staining may be considered a useful screening test. While negative staining almost always correlated with a lack of gene amplification, positive membranous staining, especially 2+, did not predict gene amplification. The low interobserver reproducibility in separating 2+ from 3+ cases necessitates further confirmation by FISH before treatment decisions are made.

Adenocarcinoma↗
PubMed2000

Tubular carcinoma of the breast: mammographic and sonographic features.

OBJECTIVE: The purpose of this study was to define specific mammographic and sonographic features of tubular carcinoma of the breast. MATERIALS AND METHODS: Seventeen pathologically confirmed cases of tubular carcinoma were characterized retrospectively by two radiologists. Mammograms and sonograms were available for all patients. RESULTS: Fifteen of the 17 tubular carcinomas appeared as irregularly shaped masses with spiculated margins on mammography. Sixteen of the 17 masses had central densities. Spicules longer than the diameter of the central lesion were noted in eight (53%) of 15 tubular carcinomas. Eight tubular carcinomas had associated calcifications, with calcifications suspected of being malignant in four cases. On sonography, 15 hypoechoic masses were seen. The margins of the masses on sonography were described as ill-defined in 14 (93%) of the 15 cases. Posterior acoustic shadowing was present in 14 of the 15 cases. CONCLUSION: Tubular carcinomas are usually seen on mammography as irregularly shaped masses with central densities and spiculated margins, and most tubular carcinomas can be identified on sonography as hypoechoic masses with ill-defined margins and posterior acoustic shadowing. Although the mammographic and sonographic features of tubular carcinoma are not sufficiently specific to differentiate tubular carcinomas from radial scars, sonography can be useful for guiding biopsies and evaluating for multifocal and multicentric disease.

Adenocarcinoma↗
PubMed1999

Occurrence of allergic conditions in asthmatics with analgesic intolerance.

BACKGROUND: The study aimed to determine whether allergic conditions accompany analgesic intolerance. METHODS: A total of 132 analgesic-intolerant patients with bronchial asthma admitted to the adult allergy unit from January 1991 to October 1997 and 103 patients with bronchial asthma randomly selected from among the asthmatics referred to our department between January and October 1997 were enrolled in the study. Those having analgesic intolerance and bronchial asthma were accepted as group I; patients having only asthma were accepted as group II. A standard questionnaire was completed for all the patients. Physical examination, routine skin prick tests, determination of total IgE levels and blood type, and oral analgesic provocation tests were also performed. RESULTS: The results showed that some allergic conditions were significantly more common in group I (22.7% and 7.8% for food allergy/intolerance [P<0.05], 16.7% and 7.8% for antibiotic allergy, 16.7% and 2.9% for dermographism, 9.8% and 1.0% for metal allergy, and 9.1% and 1.0% for chronic urticaria for groups I and II, respectively [P<0.001]). In addition, the mean of the total IgE level in the serum was higher in group I than group II (77.6 and 53.7 IU/ml; P<0.05), and the cumulative analgesic consumption was more in group I (14.2+/-17.1 and 9.1+/-12.5 boxes; P<0.05). CONCLUSIONS: Dermographism; chronic urticaria; antibiotic, metal, and food allergy; high levels of total IgE; and a high amount of cumulative analgesic consumption may be the conditions accompanying analgesic intolerance in asthmatics.

Adult↗