Stage IB1 cervical cancer patients with an MRI-measured tumor size < or = 2 cm might be candidates for less-radical surgery.

OBJECTIVES: To examine the correlation between histopathology and magnetic resonance imaging (MRI) measured tumor size and define whether patients with Stage IB1 cervical cancer with an MRI-measured tumor size < or = 2 cm can be candidates for less-radical surgery. MATERIALS AND METHODS: The authors retrospectively reviewed 200 patients with Stage IB1 cervical cancer who underwent radical hysterectomy (class III) and pelvic lymphadenectomy. The largest diameter of the tumor was determined by MRI in 52 consecutive cases. RESULTS: Regarding risk factors for parametrial involvement, only tumor size and age are known before definitive surgery without conization. Multivariate analysis of these risk factors revealed that both tumor size and old age were independently associated with parametrial involvement. Eighty-eight patients had a tumor size < or = 2 cm and an age < or = 50 years, two of which (2.3%) had parametrial involvement. In 52 consecutive patients, a significant correlation between histopathology- and MRI-measured tumor size was found (r = 0.787). Twenty-three patients had an MRI-measured tumor size < or = 2 cm, none of which had parametrial involvement. CONCLUSIONS: Patients with Stage IB1 cervical cancer lesions with a tumor size < or = 2 cm measured by MRI and age < or = 50 years can be treated with less-radical surgery.

Feasibility of delta-shaped anastomoses in totally laparoscopic distal gastrectomy.

BACKGROUND: Delta-shaped (DS) anastomosis is a new reconstruction method for totally laparoscopic distal gastrectomy (TLDG) using a linear stapler. We evaluated the feasibility of using this method for TLDG. METHODS: A retrospective analysis was performed in 114 patients who underwent TLDG with DS anastomosis. Twenty-four patients reconstructed with a Roux-en-Y (RY) anastomosis during the same period were analyzed as control subjects. RESULTS: The patient characteristics of DS and RY anastomoses were slightly different in terms of tumor location and extent of lymph node dissection, since this was not a prospective comparative study. Blood loss, postoperative complication rate and postoperative hospital stay were not different between the two groups. There was only 1 case of anastomotic leakage, and no case of anastomotic stricture after DS anastomosis. The length of the operation using DS anastomosis was significantly shorter than for RY anastomosis. The rates of body weight loss were not significantly different at 1 year after the operation. CONCLUSIONS: Although this was a small retrospective analysis, DS anastomosis was feasible, required a shorter operation time, and had no associated complications. This method can therefore be recommended as a standard procedure for TLDG.

Impact of the 12-gene recurrence score assay on deciding adjuvant chemotherapy for stage II and IIIA/B colon cancer: the SUNRISE-DI study.

BACKGROUND: Recent advances in adjuvant chemotherapy for early colon cancer have widened physicians' recommendations on the regimen and duration (3 or 6 months) of the treatment. We conducted this prospective study to evaluate whether the 12-gene recurrence score (12-RS) assay affected physicians' recommendations on adjuvant treatment selection. PATIENTS AND METHODS: Patients with stage IIIA/IIIB or stage II colon cancer were enrolled. After the patients discussed adjuvant treatment with their treating physicians, the physicians filled in the questionnaire before assay indicating the treatment recommendation. When the 12-RS assay results were available, the physicians again filled in the questionnaire after assay. The primary endpoint was the rate of change in treatment recommendations from before to after the assay, with a threshold rate of change being 20%. Patients with stage IIIA/B to II were enrolled in a ratio of 2 : 1. RESULTS: Overall, the treatment recommendations changed in 40% of cases after obtaining 12-RS assay results. Recommendations were changed in 45% (80/178; 95% confidence interval, 37% to 53%; P < 0.001) and 30% (29/97; 95% confidence interval, 21% to 40%; P < 0.001) of patients with stage IIIA/B and II colon cancer, respectively. Patients with stage IIIA/B cancer had significantly more change than those with stage II cancer (P = 0.0148). From before to after the 12-RS assay, the percentage of patients whose physicians reported being confident in their treatment recommendations significantly increased from 54% to 81% in stage IIIA/B (P < 0.001) and from 65% to 83% in stage II (P < 0.001). CONCLUSION: Our study confirmed the usefulness of the 12-RS assay in aiding the physician-patient decision-making process for tailoring adjuvant chemotherapy for stage IIIA/B colon cancer.

S-1 and oxaliplatin versus tegafur-uracil and leucovorin as post-operative adjuvant chemotherapy in patients with high-risk stage III colon cancer: updated 5-year survival of the phase III ACTS-CC 02 trial.

BACKGROUND: The ACTS-CC 02 trial demonstrated that S-1 plus oxaliplatin (SOX) was not superior to tegafur-uracil and leucovorin (UFT/LV) in terms of disease-free survival (DFS) as adjuvant chemotherapy for high-risk stage III colon cancer (any T, N2, or positive nodes around the origin of the feeding arteries). We now report the final overall survival (OS) and subgroup analysis according to the pathological stage (TNM 7th edition) for treatment efficacy. PATIENTS AND METHODS: Patients who underwent curative resection for pathologically confirmed high-risk stage III colon cancer were randomly assigned to receive either UFT/LV (300 mg/m2 of UFT and 75 mg/day of LV on days 1-28, every 35 days, five cycles) or SOX (100 mg/m2 of oxaliplatin on day 1 and 80 mg/m2/day of S-1 on days 1-14, every 21 days, eight cycles). The primary endpoint was DFS and the patients' data were updated in February 2020. RESULTS: A total of 478 patients in the UFT/LV group and 477 patients in the SOX group were included in the final analysis. With a median follow-up time of 74.3 months, the 5-year DFS rate was 55.2% in the UFT/LV group and 58.1% in the SOX group [stratified hazard ratio (HR) 0.92; 95% confidence interval (CI) 0.76-1.11; P = 0.3973], and the 5-year OS rates were 78.3% and 79.1%, respectively (stratified HR 0.97; 95% CI 0.76-1.24; P = 0.8175). In the subgroup analysis, the 5-year OS rates in patients with T4N2b disease were 51.0% and 64.1% in the UFT/LV and SOX groups, respectively (HR 0.72; 95% CI 0.40-1.31). CONCLUSION: Our final analysis reconfirmed that SOX as adjuvant chemotherapy is not superior to UFT/LV in terms of DFS in patients with high-risk stage III colon cancer. The 5-year OS rate was similar in the UFT/LV and SOX groups.

D-dimer level as a risk factor for postoperative venous thromboembolism in Japanese women with gynecologic cancer.

BACKGROUND: The purpose of the present study was to evaluate whether early postoperative D-dimer levels and certain pre-, intra-, and postoperative parameters can be used to predict venous thromboembolism (VTE) in gynecologic cancer patients. MATERIALS AND METHODS: We prospectively evaluated 267 gynecologic cancer patients who underwent surgery at our institution. The plasma D-dimer level was measured serially before the operation and on certain postoperative days. After the operation, primary screening for VTE was undertaken by meticulous examination for clinical signs and elevation of the plasma D-dimer level. Seventy-five patients underwent multidetector row computed tomography and were subjected to further investigations. RESULTS: VTE was detected in 21 of the 75 patients. There were significant differences in the D-dimer value between VTE-positive and VTE-negative patients on postoperative days 3, 5, and 7. The optimal cut-off value for the postoperative D-dimer level was determined as 5 mug/ml on day 3. Logistic regression multivariate analysis revealed that high D-dimer values on postoperative day 3, the use of recombinant human erythropoietin (rHuEPO), and non-O blood group were independent risk factors for postoperative VTE. CONCLUSION: High plasma D-dimer level on postoperative day 3, the use of rHuEPO, and non-O blood group were independent risk factors for postoperative VTE.

Complications and obstetric outcomes after laser conization during pregnancy.

OBJECTIVE: The purpose of the present study was to evaluate the efficacy of diagnostic laser conization and the obstetric outcomes of patients undergoing diagnostic laser conization during pregnancy. STUDY DESIGN: The study population consisted of a consecutive series of 47 patients who presented with histologically proven carcinoma in situ microinvasive carcinoma and were treated with laser conization during pregnancy. RESULTS: Diagnostic laser conization was performed at 3-28 weeks (median, 13 weeks) of gestation. Intraoperative blood loss of > 500 ml was observed in two cases (4.3%); however, hemotransfusion was not required in either case. In the early postoperative period, two miscarriages due to preterm premature rupture of the membrane were observed. In the late postoperative period, one spontaneous abortion, three preterm deliveries, and one neonatal death were observed. All the poor obstetric outcomes were observed in the case of patients who underwent conization in the first trimester. The pathology report for the laser conization revealed that two patients (4.3%) had invasive carcinoma. Of the 47 patients, 29 (61.7%) had positive cervical margin, and 13 required postpartum surgical intervention. All patients treated were disease-free at the time of the subsequent follow-up. CONCLUSIONS: The results of the present study suggest that laser conization in pregnant patients is feasible and is comparable to cold-knife conization and loop electrosurgical excision procedures with regard to the rates of complication and obstetric outcomes. Furthermore, they indicate that the optimal time for conization is probably the second trimester.

Versican expression in human cervical cancer.

Versican expression may enhance tumour invasion and metastasis. However, the expressions of versican in cervical cancer have seldom been characterised. The aim of this study was to investigate versican expression in human cervical cancers. We immunohistochemically investigated the expression of versican protein in 174 cervical cancers and analysed the correlation with various clinicopathological features, including patient outcome. Stromal versican expression was significantly higher in patients with lymph node metastasis (p<0.0001). Epithelial versican expression was significantly higher in patients with non-squamous cell cercinoma (p=0.0003), lymph-vascular space invasion (p=0.046), lymph node metastasis (p=0.009) and ovarian metastasis (p=0.0001). Multivariate analysis showed that high epithelial versican expression was an independent prognostic factor for disease-free survival. Versican enrichment of the tumour tissue may be associated with progression in cervical cancer. Versican expression can serve as an indicator of poor prognosis in patients with cervical cancer.

Expression of the CXCR4 and CCR7 chemokine receptors in human endometrial cancer.

PURPOSE: The chemokine receptors CXCR4 and CCR7 have been suggested to play an important role in cancer progression but their expression in human endometrial cancer has not been fully characterized. The aim of this study was to investigate CXCR4 and CCR7 expression in endometrial cancers. METHODS: We immunohistochemically investigated the expression of CXCR4 and CCR7 protein in 166 endometrial cancers and analyzed the correlation with various observed clinicopathological features, including patient outcome. Fresh tumor specimens were obtained from 55 of the 166 endometrial cancer patients, and the expression levels of the CXCR4 and CCR7 genes were also examined in this subgroup. RESULTS: Our results indicate that CXCR4 and CCR7 transcripts levels are significantly higher in tumors that express the corresponding protein products. CXCR4 and CCR7 protein expression levels were found to be significantly lower in patients with endometrial tumors of a high grade. Consistent with this, the overall survival rates were significantly better in patients exhibiting higher levels of CXCR4 and CCR7 expression. CONCLUSION: We thus hypothesize that CXCR4 and CCR7 protein levels are suppressed in high-grade endometrial tumors, but that the expression of these receptors per se may not be a crucial role in tumor progression or metastasis in these cancers.

Potentiation of adriamycin cytotoxicity by dipyridamole against HeLa cells in vitro and sarcoma 180 cells in vivo.

Dipyridamole (DP) is clinically prescribed for its vasodilating and antiplatelet effects. DP also inhibits nucleoside transport and enhances cytostatic activity of antimetabolites. We obtained evidence for augmentation of the cytocidal effect of Adriamycin (ADM) by DP, both in vitro and in vivo. Nontoxic levels of DP enhanced the cytotoxicity of ADM against HeLa cells, and the 50% effective concentration of ADM was decreased 2.4-fold by DP. DP also increased the activity of ADM in clonogenic assays. Intracellular levels of ADM in the case of concomitant exposure to ADM and DP were 1.5-fold higher than in the case of exposure to ADM alone, determined using high-performance liquid chromatography. Incorporation of ADM into the cells pretreated with DP was also increased (1.4-fold), while the efflux was little affected. The growth of Sarcoma 180 tumors was prominently suppressed by the combination of ADM and DP, compared to findings with ADM alone. DP also prolonged the survival of Sarcoma 180 tumor-bearing mice, when given in combination with ADM. While the enhancement of cytostatic activity of antimetabolites has been attributed to a decrease in utilization of the salvage pathway by DP, our data show that the synergic effects of DP with ADM were the result of increased intracellular levels of ADM.

Flavone acetic acid increases the antitumor effect of hyperthermia in mice.

The combined effects of flavone acetic acid (FAA), a synthetic flavonoid, and hyperthermia on B16 melanoma cells were investigated. In vitro, FAA alone at concentrations below 100 micrograms/ml was not cytotoxic with a 60-min exposure at 37 degrees C. Hyperthermia at 43 degrees C for 60 min enhanced the cytotoxicity of FAA only at concentrations over 100 micrograms/ml. Inhibition of the growth of B16 melanoma solid tumor by FAA and/or hyperthermia was examined in vivo. FAA (100-200 mg/kg) inhibited tumor growth in a dose-dependent manner. The combined treatment of FAA (200 mg/kg) and hyperthermia (43 degrees C, 15 min) significantly inhibited tumor growth compared to a treatment of FAA or hyperthermia alone. The maximum antitumor effect of FAA combined with hperthermia was obtained when FAA was administered 2 or 4 h before heat. The significantly increased cytotoxicity of FAA combined with hyperthermia seems to relate to specific decreases in tumor blood flow, a reduction in tumor pH, and an increased tumor temperature, without altering pH in the normal tissues. This combined treatment of FAA and hyperthermia warrants further study for treating subjects with solid tumors.

cis-Diamminedichloroplatinum(II) resistant human tumor cell lines are collaterally sensitive to PtCl4(Rh-123)2: evidence for mitochondrial involvement.

Three human tumor cell lines made resistant to cis-diamminedichloroplatinum(II) (CDDP), SCC-25/CP, MCF-7/CP, and C13, are more sensitive to rhodamine-123 [tetrachloroplatinum(II)] [(PtCl4(Rh-123)2] than are the corresponding parental cell lines. The CDDP-resistant cells have higher intracellular concentrations of PtCl4(Rh-123)2 for the same exposure than do the parent cells. Each of the CDDP-resistant cell lines has an increased level of cytochrome c oxidase activity compared with the parent cell lines, indicating that the resistant cells have greater mitochondrial mass or activity than the parent cells. In fact, there was a linear correlation between the increase in cytochrome c oxidase activity and the increased sensitivity to PtCl4(Rh-123)2 in the CDDP-resistant lines. Exposure of the cells to each of the mitochondrial effectors, chloramphenicol, FCCP, oligomycin, or antimycin prior to and during exposure to CDDP or PtCl4(Rh-123)2 had variable effects on the cytotoxicity of the platinum complexes in the parental lines. However, there was a consistent decrease in the cytotoxicity of PtCl4(Rh-123)2 in the CDDP-resistant cells in the presence of the mitochondrial effectors such that, in some cases, the CDDP-resistant lines were now less responsive to PtCl4(Rh-123)2 than were the parent cell lines. These studies indicate that mitochondrial alterations may be an important component of CDDP resistance in these cell lines and that PtCl4(Rh-123)2 may represent a prototype platinum complex useful in the treatment of CDDP resistant tumors.

Loss of basement membrane heparan sulfate expression is associated with tumor progression in endometrial cancer.

Perlecan is a major heparan sulfate proteoglycan (HPSG) of the basement membrane (BM) and binds to various cytokines and growth factors via its heparan sulfate glycosaminoglycan (HS-GAG) chains. The aim of this study was to investigate BM HS-GAG expression in endometrial cancers. We investigated the expression of BM HS-GAG by immunohistochemistry in 109 endometrial cancers and analyzed correlations with various clinicopathological features. The HS-GAG expression index was significantly lower in cases of advanced stage, high-grade, deep myometrial invasion, positive peritoneal cytology, lymph vascular space invasion and lymph node metastasis. There was no association between HS-GAG expression status and patient outcome. Decreased HS-GAG expression of BM is associated with tumor progression, but is not be a useful prognostic factor in patients presenting with endometrial cancer.

Phase I pharmacokinetic study of the hypoxic cell sensitizer etanidazole with carboplatin and cyclophosphamide in the treatment of advanced ovarian cancer.

PURPOSE: A Phase I study was undertaken to determine the maximum tolerated dose of the hypoxic cell sensitizer etanidazole which could be administered with carboplatin and cyclophosphamide, to determine whether adequate serum levels of etanidazole were achieved to allow for alkylating agent sensitization, and whether pretreatment with etanidazole altered carboplatin pharmacokinetics. METHODS AND MATERIALS: Patients received 2 g/m2 of intravenous etanidazole followed by a second dose of 4 g/m2 90 min later, followed by intravenous carboplatin (300 mg/m2) and cyclophosphamide (600 mg/m2) for four treatment cycles. Patients received an additional two cycles of carboplatin and cyclophosphamide without etanidazole. RESULTS: Two patients who received a total of 24 g/m2 of etanidazole developed Grade 1 neurotoxicity, and therefore etanidazole doses were not escalated further. The grade of granulocytopenia was worse after cycles with etanidazole than after those without (p = 0.03), but clinical outcome was not different. Etanidazole levels were adequate for alkylating agent sensitization (> 70 ug/ml) in all patients for the majority of the 7 h of testing. Pharmacokinetic data suggested t1/2 alpha and t1/2 beta for carboplatin were prolonged after pretreatment with etanidazole. CONCLUSION: Etanidazole, 2 g/m2 followed by 4 g/m2 90 min later, is safe and results in adequate serum levels for alkylating agent sensitization. Neurotoxicity appears to prevent dose escalation of etanidazole, and an interaction between etanidazole and carboplatin may have enhanced neurotoxicity in these patients.

Differences in in vivo and in vitro sequence-specific sites of cisplatin-DNA adduct formation and detection of a dose-response relationship.

The cytotoxic and mutagenic properties of the anticancer drug cis-diammine-dichloroplatinum(II) (cisplatin) are mediated by bifunctional adducts between purines. Experiments performed in this study employed a new repetitive thermal-cycling technique to detect cisplatin adduct formation following exposure of cells in culture (in vivo) or following treatment of purified DNA (in vitro exposure). The initial goal of this study was to determine if cisplatin-DNA adduct formation could be measured accurately using phosphor-imaging over a broad concentration range. If this proved possible, it would then be feasible to determine if adduct formation differed within chromatin compared with purified DNA. There were no significant differences in the cisplatin-DNA adduct pattern induced in closed circular or linear double-stranded plasmids in vitro, suggesting that this type of tertiary structural change does not affect the formation of adduct sites. Sequence-specific DNA adduct formation within a human repetitive DNA target sequence, alphoid DNA, following cisplatin treatment of prostate cancer cells in culture (in vivo) and treatment of purified DNA in vitro revealed consistent increases in adduct formation over a broad concentration range, validating the experimental technique. Comparing preferences for cisplatin adduct site formation under these different conditions of exposure demonstrated statistically significant differences. Similar differences were detected for cisplatin repair-deficient Xeroderma pigmentosum cells treated in cell culture, indicating that in vivo/in vitro preferences for adduct site formation are not the result of DNA repair in vivo.

Decreased tumor oxygenation after cyclophosphamide, reoxygenation and therapeutic enhancement with a perflubron emulsion carbogen breathing.

Oxygen profiles of the rat mammary 13672 carcinoma were determined using a pO2 histograph prior to treatment and 24 h and 48 h after i.p. administration of a single dose of cyclophosphamide (300 mg/kg). The tumors were severely hypoxic at 24 h post the administration of cyclophosphamide. There was little increase in oxygenation of the tumors at 48 h post therapy compared with 24 h post therapy indicating that reoxygenation after cyclophosphamide was occurring very slowly in this tumor. Carbogen breathing improved the oxygenation of the tumors under each of the conditions studied. Administration of the perflubron emulsion (8 ml/kg) produced little or no change in the oxygenation of the tumors under normal air breathing conditions. However, the addition of carbogen breathing to administration of the perflubron emulsion increased the oxygenation of the tumors to levels equal to or greater than carbogen breathing at the mean/median pO2's. Perhaps most significantly, administration of the perflubron emulsion with carbogen breathing increased the oxygenation of the most hypoxic regions of the tumors but carbogen breathing alone did not. The growth delay of the Lewis lung carcinoma increased with increasing dose.of the perflubron emulsion along with cyclophosphamide (3 x 150 mg/kg) and carbogen breathing (6 h). This combination treatment was most effective when the cyclophosphamide was prepared in the perflubron emulsion. The number of lung metastases decreased in a manner parallel with increased efficacy of the treatment toward the primary tumor.

Reversal of drug-resistance by exposure of mcf-7 or mcf-7 cddp human breast-carcinoma cells to sr-4233 or etanidazole under hypoxic conditions.

Drug resistance is a major problem in cancer therapy. The MCF-7/CDDP cell line, a subline of the MCF-7 human breast carcinoma cell line which is resistant to cis-diamminedichloroplatinum(II), is also resistant to carboplatin, D-tetraplatin and to a lesser degree to melphalan, thiotepa and BCNU compared with the MCF-7 parental cell line. This resistance persists both under normally oxygenated conditions and after 2 h of exposure to hypoxic conditions prior to exposure to the antitumor alkylating agents under normally oxygenated conditions. When the MCF-7 parental cells and MCF-7/CDDP cells were treated with SR-4233 (20 muM) or etanidazole (5 mM) for 2 h prior to and during exposure to the antitumor alkylating agents there was no change in the sensitivity and resistance patterns of the cell lines. However, if the MCF-7 parental cells and the MCF-7/CDDP cells were exposed to SR-4233 (20 muM) or etanidazole (5 mM) for 2 h under hypoxic conditions followed by release of the hypoxia and exposure to the antitumor alkylating agents for 1 h under normally oxygenated conditions the resistance of the MCF-7/CDDP was reversed so that both the MCF-7 parental and MCF-7/CDDP cell lines were essentially equally sensitive to the six antitumor alkylating agents. These results indicate that non-cytotoxic concentrations of modulators such as SR-4233 or etanidazole may be useful in reversing resistance to the.

The quinolinone derivative vesnarinone potentiates the cytotoxicity of doxorubicin in HL-60 leukemia cells.

Vesnarinone, (3,4-dihydro-6-[4-(3,4-dimethoxybenzoyl)-1- piperazinyl]-2(1H)-quinolinone), a quinolinone derivative, is a positive inotropic agent. We examined the cytotoxicity either by vesnarinone alone or in combination with doxorubicin (DXR), in vitro. The cytotoxic effect of vesnarinone against HL-60 cells did not increase, even at concentrations as high as (50 mu g/ml). The cytotoxicity of DXR, however, was enhanced after being combined with 30 mu g/ml of vesnarinone. The intracellular level of DXR increased when DXR was administered after incubation with vesnarinone and the efflux of DXR was delayed when the cells were incubated in the presence of vesnarinone after DXR exposure. Flow cytometry showed that the combination of DXR and vesnarinone increased the cell population below the G(0)/G(1) region. Vesnarinone induced DNA ladder formation, but only when these cells were incubated for 72 h, while in addition, when DXR was combined with vesnarinone, the DNA ladder formation was enhanced. Based on the above findings, we thus conclude that the cytotoxicity of DXR was enhanced when combined with vesnarinone.

Reduced oxygenation in a rat mammary carcinoma after chemo- or radiation therapy and reoxygenation with perflubron emulsion/carbogen breathing.

Rat 13672 mammary carcinoma tumors were grown subcutaneously in the hind legs of female Fischer 344 rats to a volume of about 1 cm3. Tumor oxygenation was measured using an Eppendorf PO2 histograph. Tumor oxygen measurements were made under four conditions: (a) normal air breathing, (b) carbogen breathing, (c) after intravenous administration of a perflubron emulsion (8 ml/kg) with air breathing and (d) after intravenous administration of a perflubron emulsion (8 ml/kg) with carbogen breathing. Tumor oxygenation was examined without treatment or 24 h and 48 h after treatment with cyclophosphamide (300 mg/kg, i.p.) or cisplatin (8 mg/kg, i.p.] or after the fifth dose of a daily regimen of 3-Gy irradiation (5 x 3 Gy). Under normal air-breathing conditions 49% of the tumor had a PO2 < or = 670 Pa (5 mm Hg). The degree of hypoxia in the tumors increased after each treatment such that 24 h after treatment 65%-85% of the oxygen readings were < or = 670 Pa and 48 h after treatment 60%-74% of the oxygen readings were < or = 670 Pa. Administration of the perflubron emulsion/carbogen atmosphere increased the oxygen content of the tumors both without treatment and after each of the treatments. A knowledge of tumor oxygen content over the course of treatment and the ability to increase tumor oxygen should allow for the development of more rational treatment combinations and better treatment outcomes.

Visual recognition of triamines by phenolphthalein derivatives: consideration of the structure of the colored complex.

[structure: see text] A hybrid molecule 1 consisting of phenolphthalein and two crown ether moieties can be used to discriminate the length of linear triamines strictly by color development. The purple color is developed most deeply at -10 degrees C and fades with either an increase or decrease in temperature.

Visual enantiomeric recognition using chiral phenolphthalein derivatives.

[structure: see text] Optically active artificial host molecules 2-5 based on a phenolphthalein skeleton have been prepared for visual enantiomeric recognition of alanine derivatives 8 and 9. The receptor 3 discriminates (R)-8 and (R)-9 from (S)-8 and (S)-9, respectively, to develop a purple color.