Inhibition of melanoma cell proliferation by strobilurins isolated from mushrooms and their synthetic analogues

Strobilurins A and X, isolated from Mucidula venosolamellata culture extracts, demonstrated potent inhibition of human melanoma G-361 cell proliferation. Strobilurin X exhibited milder inhibitory effects on human fibroblast cells (NB1RGB) compared to strobilurin A. Additional strobilurin-related compounds were isolated from the other mushroom species. Oudemansins A and B displayed weaker activities on G-361 cells than strobilurins A and B, respectively, emphasizing the importance of a conjugated double-bond structure. Among isolated compounds, strobilurin G showed the lowest IC50 value for G-361 cells. Additional strobilurins bearing various substituents on the benzene ring were synthesized. Synthetic intermediates lacking the methyl β-methoxyacrylate group and a strobilurin analogue bearing modified β-methoxyacrylate moiety showed almost no inhibitory activity against G-361 cells. The introduction of long or bulky substituents at the 4' position of the benzene ring of strobilurins enhanced the activity and selectivity, suggesting differential recognition of the benzene ring by G-361 and NB1RGB cells.

A Case of Jejunal Artery Aneurysm Successfully Treated with Endovascular Embolization

Jejunal artery aneurysms are extremely rare; only 58 cases have been reported up to 2022. The high rupture rate necessitates a curative treatment. Only four cases of true jejunal artery aneurysms treated with endovascular embolization were reported. We report a case of a 75-year-old man with a true jejunal artery aneurysm who was successfully treated with endovascular embolization. The aneurysm was located in the third jejunal branch. The proximal and distal distance to the superior mesenteric artery and the first bifurcation of the third jejunal branch, respectively, were too short to perform isolation. First, we performed packing in the aneurysm, followed by secondary parent artery embolization. Finally, we achieved total occlusion of the aneurysm and its parent artery with preserved distal intestinal blood flow.

Identification of Cyclocybe erebia metabolites that affect the circadian rhythm of Eluc expression under control of Bmal1 promoter in mouse fibroblast cells

Pharmacological intervention of circadian rhythms is a potentially useful approach for ameliorating various health problems caused by disturbed circadian rhythms including sleep disorder and metabolic diseases. To find compounds that affect circadian rhythms, we screened mushroom extracts using mouse cells expressing the luciferase gene under the control of the mouse Bmal1 promoter. The culture filtrate extract from the basidiomycete Cyclocybe erebia enhanced the oscillation of bioluminescence caused by the expression of the luciferase gene and prolonged the period of bioluminescence. Bioassay-guided fractionation of the extract resulted in purification of compounds 1 and 2. Spectroscopic analyses along with single-crystal X-ray diffraction analysis, revealed that these compounds were diterpenoids with a unique skeleton and a fused ring system comprising 3-, 7-, and 5-membered rings. Compounds 1 and 2 were named cyclocircadins A and B, respectively. These findings suggested that natural diterpenoids could be a source of compounds with the activity affecting circadian rhythms.

A Case of Refractory Esophageal Varices Caused by an Inferior Mesenteric Arteriovenous Malformation with All Portal System Occlusion Successfully Treated via Transarterial Embolization

Inferior mesenteric arteriovenous fistulas/malformations are rare, reported in only 40 cases as of 2021. Their main manifestations include portal hypertension and ischemic bowel disease. We report the case of a 50-year-old man with refractory esophageal varices caused by this condition that was successfully treated with transarterial embolization. Computed tomography revealed an inferior mesenteric arteriovenous malformation and ascending blood flow into the esophageal varices through a remarkably dilated marginal vein. All portal systems were occluded, possibly because of the myointimal hyperplasia of the inferior mesenteric vein. The patient recovered without hemorrhagic events after transarterial embolization and endoscopic injection sclerotherapy. This is the first report of an inferior mesenteric arteriovenous malformation resulting in refractory esophageal varices with all-portal system occlusion successfully treated with transarterial embolization.

Helminth Fauna of Juvenile Green Sea Turtles (Chelonia mydas) from Rio de Janeiro State, Brazil

The helminth fauna of juvenile green sea turtles (Chelonia mydas Linnaeus, 1758) is still poorly known. Herein, we study the gastrointestinal helminths of 28 juvenile green sea turtles found stranded on the north coast of Rio de Janeiro state, Brazil. All turtles were infected showing a rich helminth fauna. In total, 14802 trematodes belonging to 30 species and 5 families including Micros-caphidiidae, Plagiorchiidae, Pronocephalidae, Hapalotrematidae, and Telorchiidae were recovered. An unidentified nematode specimens was also found. The mean intensity was 536 (95% CI = 362 - 853) (range: 1 - 2831), and the species richness was 7.86 (95% CI = 6.46 - 9.21) (range: 1 - 17). The coast of Rio de Janeiro state represents new locality records for Angiodictyum posterovitellatum, Microscaphidium aberrans, M. warui, Octangium hyphalum, O. sagitta, Enodiotrema reductum and Pleurogonius laterouterus. This study confirms that the green sea turtle harbors the richest helminth fauna among sea turtle species and provides useful information on the gastrointestinal helminths of a poorly known stage in the life cycle of this endangered chelonian.

The diagnostic challenge of non-traumatic bladder rupture: a pictorial essay

Non-traumatic bladder rupture (NTBR) is relative rare pathology including spontaneous rupture and iatrogenic injury. As increasing the medical intervention for the pelvic malignancy or elderly population, NTBR will be encountered more frequently. There are few previous studies summarizing the imaging features of NTBR. We reviewed imaging characteristics of 18 previous cases of NTBR experienced. In addition, 3 presentative cases that can be a pitfall to differentiate from NTBR. The aim of this article is to clarify the key CT findings of NTBR and its pitfalls.

Zootechnical indices and digestibility in juveniles of tambaqui Colossoma macropomum fed a diet containing particulate maize

Three experiments were done with different particle sizes of corn feed on its zootechnical performance, passing rate and apparent digestibility of juvenile tambaqui (Colossoma macropomum). In the first, 200 juveniles were used and distributed in 20 tanks (220 L), 10 fish per unit (four replicates). The experimental system used to record passage time was composed of five incubators with 200 L. In the second, 75 juveniles were used per 55 days (three replications). In the third, 75 juveniles were used and distributed in five incubators of 200 L. All experiments were performed randomly. Different linear behavior treatments were observed for apparent digestibility of crude protein; and the smaller particle size (150 μm) had better results digestibility. smaller particle size of the corn had better results, affected the growth performance of tambaqui and the apparent digestibility of crude protein and ether extract. Thus, is recommended that a particle size of 150 μm of corn be used for tambaqui.

National survey on total-body irradiation prior to reduced-intensity stem cell transplantation in Japan: The Japanese Radiation Oncology Study Group

Reduced-intensity stem cell transplantation (RIST) minimizes the adverse effects of traditional hematopoietic stem cell transplantation, and low-dose total-body irradiation (TBI) is administered over a short period prior to RIST (TBI-RIST). Different institutes adopt different approaches for the administration of TBI-RIST, and since no study had previously investigated this issue, a survey of the TBI schedules in Japan was conducted. In October 2015, the Japanese Radiation Oncology Study Group initiated a national survey of TBI-RIST procedures conducted between 2010 and 2014. Of 186 institutions performing TBI, 90 (48%) responded to the survey, 78 of which performed TBI-RIST. Of 2488 patients who underwent TBI for malignant disease at these institutions, 1412 (56.8%) patients were treated for leukemia, 477 (19.2%) for malignant lymphoma, 453 (18.2) for myelodysplastic syndrome, 44 (1.8%) for multiple myeloma, and 102 (4.1%) for other malignant diseases. Further, 206 (52.0%) of 396 patients (a high proportion of patients) who underwent TBI for benign disease had aplastic anemia. The TBI-RIST equipment and treatment methods were similar to those used for myeloablative regimens. Routinely shielded organs included the lungs (43.6%), eyes (50.0%) and kidneys (10.2%). The ovaries (14.1%), thyroid (6.4%) and testicles (16.7%) were also frequently shielded, possibly reflecting an emphasis on shielding reproductive organs in children. TBI-RIST was performed more frequently than myeloablative conditioning in patients with benign disease. Genital and thyroid shielding were applied more frequently in patients treated with TBI-RIST than in patients treated with myeloablative conditioning. In conclusion, this study indicates the status of TBI-RIST in Japan and can assist future efforts to standardize TBI-RIST treatment methods and to design a future multicenter collaborative research study.

National survey of myeloablative total body irradiation prior to hematopoietic stem cell transplantation in Japan: survey of the Japanese Radiation Oncology Study Group (JROSG)

A myeloablative regimen that includes total-body irradiation (TBI) before hematopoietic stem cell transplantation results in higher patient survival rates than achieved with regimens without TBI. The TBI protocol, however, varies between institutions. In October 2015, the Japanese Radiation Oncology Study Group initiated a national survey of myeloablative TBI (covering 2010-2014). Among the 186 Japanese institutions performing TBI, 90 (48%) responded. The 82 institutions that had performed myeloablative TBI during this period treated 2698 patients with malignant disease [leukemia (2082 patients, 77.2%), malignant lymphoma (378, 14%)] and 37 with non-malignant disease [severe aplastic anemia (20, 54%), inborn errors of metabolism (5, 14%)]. A linear accelerator was used at all institutions. The institutions were divided into 41 large and 41 small institutions based on the median number of patients. The long source-surface distance technique was the method of choice in the 34 institutions (82.9%) and the moving-couch technique in the 7 (17.1%) in the large institutions. The schedules most routinely used by the participating institutions consisted of 12 Gy/6 fractions/3 days (26 institutions, 63.5%) in the large institutions. The dose rate varied from 5 to 26 cGy/min. The lungs and lenses were routinely shielded in 23 large institutions (56.1%), and only the lungs in 9 large institutions (21.9%). At lung-shielding institutions, the most frequent maximum acceptable total dose for the lungs was 8 Gy (19 institutions, 27.5%). Our results reveal considerable differences in the TBI methods used by Japanese institutions and thus the challenges in designing multicenter randomized trials based on TBI.

Early disease progression in patients with localized natural killer/T-cell lymphoma treated with concurrent chemoradiotherapy

Prognosis of patients with localized nasal extranodal natural killer/T‐cell lymphoma, nasal type (ENKL) has been improved by non‐anthracycline‐containing treatments such as concurrent chemoradiotherapy (CCRT). However, some patients experience early disease progression. To clarify the clinical features and outcomes of these patients, data from 165 patients with localized nasal ENKL who were diagnosed between 2000 and 2013 at 31 institutes in Japan and who received radiotherapy with dexamethasone, etoposide, ifosfamide, and carboplatin (RT‐DeVIC) were retrospectively analyzed. Progression of disease within 2 years after diagnosis (POD24) was used as the definition of early progression. An independent dataset of 60 patients with localized nasal ENKL who received CCRT at Samsung Medical Center was used in the validation analysis. POD24 was documented in 23% of patients who received RT‐DeVIC and in 25% of patients in the validation cohort. Overall survival (OS) from risk‐defining events of the POD24 group was inferior to that of the reference group in both cohorts (P < .00001). In the RT‐DeVIC cohort, pretreatment elevated levels of serum soluble interleukin‐2 receptor (sIL‐2R), lactate dehydrogenase, C‐reactive protein, and detectable Epstein‐Barr virus DNA in peripheral blood were associated with POD24. In the validation cohort, no pretreatment clinical factor associated with POD24 was identified. Our study indicates that POD24 is a strong indicator of survival in localized ENKL, despite the different CCRT regimens adopted. In the treatment of localized nasal ENKL, POD24 is useful for identifying patients who have unmet medical needs.

Early disease progression in patients (pts) with newly diagnosed localized nasal extranodal NK/T-cell lymphoma, nasal type (ENKL) treated with radiotherapy with dexamethasone, etoposide, ifosfamide, and carboplatin (RT-DeVIC)

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Background: Approximately 25% of all pts with localized nasal ENKL experience disease progression during the first two years (yrs) after diagnosis under new treatments including concurrent chemoradiotherapy. The clinical features of those pts are largely unknown. Methods: The database of our study (NKEA project; UMIN000015491) was used for the present analysis. Data from pts with newly diagnosed localized (stage IE and contiguous IIE) nasal ENKL diagnosed between 2000 and 2013 at 31 institutes in Japan and treated with RT-DeVIC were retrospectively analyzed. Progression of disease within 2 yrs (POD24) (Casulo, JCO 2015) was applied as the definition of early progression. Results: Of 162 pts, 38 were in the POD24 group (23%) and 124 were in the reference group. Treatment yrs and doses of RT and DeVIC were not associated with the incidence of POD24. With a median follow-up of 5.8 yrs, the overall survival (OS) of the POD24 group was inferior to that of the reference group ( P < 0.00001; 2-yr OS, 26% vs. 100%; 5-yr OS, 23% vs. 89%). The POD24 group showed the following features more frequently than the reference group: serum soluble interleukin-2 receptor (sIL-2R) level > upper limit of normal (ULN) (25/33, 76%; P = 0.000012), C-reactive protein (CRP) > ULN (28/37, 76%; P = 0.013), and detectable Epstein-Barr virus (EBV)-DNA in peripheral blood (15/17, 88%; P = 0.033). The positive predictive value and negative predictive value of elevated sIL-2R for POD24 were 42% and 90%, respectively; those of elevated CRP were 31% and 87%, respectively; and those of detectable EBV-DNA were 39% and 90%, respectively. Of the 9 pts who were negative for all three factors, none experienced POD24. A multivariate analysis in the POD24 group identified elevated sIL-2R as an independent predictive factor for worse OS (HR 3.16; 95% CI, 1.07 - 9.32). Conclusions: Pretreatment sIL-2R, CRP, and EBV-DNA were associated with POD24 among pts with localized nasal ENKL treated with RT-DeVIC. The strong association of elevated sIL-2R with early progression and short OS in the POD24 group provides a rationale for targeting strategies.

Walking Disability in Patients with Pelvic Insufficiency Fracture after Radiotherapy for Uterine Cervical Cancer

Objective

Radiotherapy is an essential component of curative or palliative therapy for patients with uterine cervical cancer. Although advances in radiotherapy have led to longer survival, survivors may consequently be at risk of pelvic insufficiency fracture (PIF). We retrospectively reviewed medical records and clinical outcomes to assess the impact of PIF on walking disability.

Methods

Between January 2002 and December 2009, 145 uterine cancer patients treated with radiotherapy in our hospital were reviewed. Among these, 15 patients (10.3%) were diagnosed with PIF. The types of fractures were identified according to the AO/OTA classification system. Medical records were examined to establish the time to first diagnosis of PIF, the type of fracture, and clinical outcomes. Disability was assessed using Barthel index mobility scores.

Results

The median time to PIF detection was 16 months. Of the 15 patients with PIF, 14 had type B fractures (7 cases of B2 and 7 cases of B3) and 1 had a type C fracture. Among 11 patients with pelvic pain, 6 achieved pain control but 5 patients with bilateral lesions in the posterior arch or lateral compression of the sacrum developed pain that finally resulted in walking disability and a lower performance status.

Conclusions

PIF causes severe motor disturbance in patients with unstable fracture types. Routine imaging checkups were useful during the 5 years after completion of radiotherapy; in nine patients the fracture progressed for longer than 1 year. In cancer rehabilitation for PIF patients, continuous assessment is essential for predicting walking disability.

Histopathological findings in lungs of hawksbill turtles collected on the coasts of the states of Espírito Santo and Rio de Janeiro, Brazil

ABSTRACT The present work aimed to report the histopathological findings verified in lungs of hawksbill turtles (Eretmochelys imbricata) retrieved from the coasts of the states of Espírito Santo and Rio de Janeiro, Brazil. Between the years 2010 and 2014, 29 E. imbricata individuals were found stranded on the coasts, already dead or dying during treatment. Lung samples of all specimens were collected during necropsies, fixed in 10% neutral buffered formalin, subjected to routine histological processing and classified histomorphologically. The findings revealed that 37.93% of the specimens presented lung lesions. Of these, 90.91% were rescued alive and 9.09% were found dead; 63.63% were females and 36.37% were males. The mean weight was 5.44 Kg and the mean length 39 cm, characterizing young individuals. The animals originated from São Francisco de Itabapoana - RJ, Aracruz - ES, São Mateus - ES, Guarapari - ES, Linhares - ES, Itapemirim - ES, and Anchieta - ES. Macroscopic analysis revealed presence of foam, hyperemia, nodules in the parenchyma, cyst and caseous material. Microscopic examination evidenced heterophilic bronchopneumonia, parasitic granulomatous pneumonia caused by spirorchiids, bacterial granulomatous pneumonia, fungal granulomatous pneumonia, and congestion. It was concluded that juvenile specimens of Eretmochelys imbricata, females and males, originated from the states of Espírito Santo and Rio de Janeiro and found stranded both alive or dead, have significant lung lesions, mainly inflammatory ones, associated or not with infectious agents.

Análise histomorfométrica do útero na espécie canina do nascimento aos seis meses de idade

Objetivou-se caracterizar para a espécie canina o desenvolvimento histológico uterino do nascimento aos seis meses de idade. Foram analisados úteros (n=32) de animais com idades entre um e 180 dias pós-nascimento (DPN), distribuídos em oito grupos: G1-1 DPN (1 Yorkshire Terrier, 1 Poodle, 2 Sem Raça Definida (SRD)/peso médio (Pm)=190g), G2-15 DPN (2 Yorkshire Terrier e 2 SRD/Pm=354g), G3-30 DPN (1 Rottweiler, 1 Poodle, 2 SRD/Pm=985g), G4-45 DPN (1 Poodle, 3 SRD/Pm=1,1kg), G5-60 DPN (1 Yorkshire Terrier, 1 Poodle e 2 SRD/Pm=1,4kg), G6-90 DPN (4 SRD/Pm=2,8kg), G7-120 DPN (1 Poodle e 3 SRD/Pm=6,6kg) e G8-180 DPN (1 Rottweiler, 1 Poodle e 2 SRD/Pm=11kg). A análise histológica constituiu de mensurações das espessuras (µm) da parede uterina, miométrio, endométrio, assim como diâmetro (µm) e número de glândulas endometriais. A análise estatística demonstrou estabilidade e homogeneidade nas estruturas avaliadas com coeficientes de variação baixos (<10%). Observou-se: útero com um DPN: epitélio com células cúbicas simples, miométrio rudimentar, presença de perimétrio e ausência de glândulas endometriais; aos 15 DPN: desenvolvimento de estrutura primordial de formação das glândulas endometriais; dos 30 aos 45 DPN: endométrio e glândulas endometriais simples; aos 60 DPN: glândulas endometriais em lâmina própria com ramificações e discreto pregueamento endometrial; de 90 a 180 DPN: todas as estruturas uterinas apresentaram histoarquitetura de um animal maduro. Todas as variáveis analisadas apresentaram correlação positiva com a idade pós-nascimento (R2≥72,2%). Conclui-se que o útero da cadela desenvolve-se continuamente do nascimento à 180 dias de vida e que apresenta-se desprovido de glândulas endometriais ao nascimento. As primeiras glândulas endometriais são observadas aos 15 dias de vida e apresenta conformação histológica de um animal adulto após 60 dias do nascimento.

Composição corporal de tambaqui alimentado com rações contendo farinha de folha de leucena

O objetivo deste trabalho foi avaliar os efeitos da inclusão de farinha de folha de leucena em dietas sobre a composição corporal de juvenis de tambaqui. Um total de 240 juvenis foram distribuídos em 12 caixas plásticas (350 L), em um delineamento experimental inteiramente casualizado com quatro tratamentos (0, 8, 16 e 24 % de inclusão de farinha de folha de leucena) e três repetições. Não houve diferença significativa (p>0,05) entre os tratamentos, indicando que é possível incluir até 24 % de farinha de folha de leucena em rações para juvenis de tambaqui, sem que haja alteração da composição corporal.

Determinação da razão ótima de espermatozóides por ovócitos de piabanha Brycon insignis (pisces - characidae)

Determinou-se a razão ótima de espermatozóides por ovócitos da piabanha Brycon insignis, utilizando-se dois machos e duas fêmeas da espécie, submetidos ao procedimento de desova induzida. Os gametas foram extrusados manualmente 200 horas-grau após a aplicação do extrato bruto de hipófise. Os ovócitos foram misturados e deste pool retiraram-se amostras com 2g de ovócitos (701 ovócitos/g). O sêmen do pool foi diluído em solução de NaCL 1,2% de tal forma que, após a adição de 1ml do sêmen diluído aos ovócitos, fossem obtidas as seguintes razões espermatozóides por ovócitos em cada tratamento: T1=86.662, T2=173.324, T3=259.986, T4=346.648 e T5=433.310. A taxa de fertilização do sêmen não diluído usado como controle foi de 65,3%. Após ativação espermática com NaHCO3 1% e fecundação, os ovos foram transferidos para as incubadoras e nelas foram observadas as seguintes percentagens de fertilização em relação à do grupo-controle: T1=35,7%, T2=53,1%, T3=79,1%, T4=93,4% e T5=87,8%. A percentagem de fertilização (em relação ao controle) aumentou de forma linear, segundo a equação de regressão: Y=15,55+0,0002297X (P<0,01; R²=0,98), até a proporção de 314.481 espermatozóides por ovócitos, após o que a taxa de fertilização se estabilizou no limite de 88%.

Amino acid residues responsible for galactose recognition in yeast Gal2 transporter

A novel, systematic approach was used to identify amino acid residues responsible for substrate recognition in the transmembrane 10 region of the Gal2 galactose transporter of Saccharomyces cerevisiae. A mixture of approximately 25,000 distinct plasmids that encode all the combinations of 12 amino acids in transmembrane 10 that are different in Gal2 and the homologous glucose transporter Hxt2 was synthesized. Selection of galactose transport-positive clones on galactose limited agar plates yielded 19 clones, all of which contained the Tyr446 residue found in Gal2. 14 of the 19 clones contained Trp455 found in Gal2, whereas the other 5 contained Cys455, a residue not found in either Gal2 or Hxt2. When Tyr446 of Gal2 was replaced with any of the other 19 amino acids, no galactose transport activity was observed in the resulting transporters, indicating that Tyr446 plays an essential role in the transport of this sugar. Replacement of 2 amino acids of Hxt2 with the corresponding Tyr446 and Trp455 of Gal2 allowed the modified Hxt2 to transport galactose. The Km of galactose transport for the modified transporter was 8-fold higher than that of Gal2. These results and other evidence unequivocally show that Tyr446 is essential and Trp455 is important for the discrimination of galactose versus glucose.

Transmembrane segment 10 is important for substrate recognition in Ga12 and Hxt2 sugar transporters in the yeast Saccharomyces cerevisiae

A systematic series of chimeras between Ga12 galactose transporter and Hxt2 glucose transporter in yeast was produced to delineate the essential domain for substrate recognition. A domain of 101 amino acids close to the COOH-terminus that has been previously identified as the critical substrate recognition region was further divided into four subdomains, by introducing five restriction enzyme sites at exactly corresponding locations of both genes without changing coding amino acids. When each of all possible 16 modified genes was expressed, all the galactose transport-active chimeras were found to possess Ga12-derived transmembrane segment (TM) 10. Of the 35 amino acids in the TM1O region, only 12 differ between Ga12 and Hxt2, indicating that these 12 amino acids include the critical residue(s) responsible for the differential recognition of galactose and glucose in these transporters.

Substrate recognition domain of the Gal2 galactose transporter in yeast Saccharomyces cerevisiae as revealed by chimeric galactose-glucose transporters

The Gal2 galactose transporter takes up galactose in yeast. A homologous glucose transporter from the same organism, Hxt2, was selected, and various chimeras between these two transporters were constructed by making use of homologous recombination in Escherichia coli. Comparison of the galactose transport activities of three series of chimeras enabled us to positively identify a crucial substrate recognition region of 101 amino acids that lies close to the carboxyl terminus of the Gal2 transporter.

Nanosecond fluorescence studies of noncovalent interaction of monomeric and dimeric intercalators with DNA

The noncovalent interaction of 2-aminodipyrido[1,2-a:3',2'-d]imidazole (Glu-P-2) and its derivatives, which are potent mutagens isolated from L-glutamic acid pyrolysate, with calf thymus DNA was studied by steady-state and nanosecond fluorescence spectroscopies. The fluorescence of these compounds exhibits static quenching by noncovalent interaction with DNA. Fluorescence lifetimes of the free and intercalated states of these compounds were determined to be 9-10 and 0.5-1 ns, respectively. The bisintercalative effect of the dimeric analogue of Glu-P-2, bis(Glu-P-2)spermine (2GP-SP), to DNA was also investigated. This 2GP-SP, which has two Glu-P-2 moieties at each end of spermine, indicates a strong intramolecular interaction exhibiting remarkable quenching of fluorescence spectrum and lifetime (tau = 3.5 ns) in the absence of DNA. In the presence of DNA, however, the 3.5-ns lifetime component of fluorescence disappeared, and a two-exponential decay of fluorescence (t = approximately 10 and 1.5 ns) was observed at a DNA concentration of more than approximately 0.001 mM P, while the solution containing a very dilute DNA concentration (less than or equal to 0.001 mM P) exhibits a three-component decay of fluorescence (1.5, 3.5, and approximately 10 ns). The potent bis intercalation of two moieties in 2GP-SP with an identical DNA molecule was suggested by the DNA-concentration dependence of these fluorescence lifetimes and their intensity.