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A Ono

Publications and source records attributed to A Ono.

304 records · Page 17Linked to original sources

Portal blood flow in the presence or absence of diffuse liver disease: measurement by phase contrast MR imaging.

BACKGROUND: In patients with diffuse liver disease, the portal flow dynamics change markedly in accordance with disease progression and would provide a useful index of progression of stage. METHODS: Portal blood flow (PBF) was measured by phase contrast magnetic resonance imaging (MRI) in 21 patients with diffuse liver disease and 20 healthy volunteers. The MRI method was validated by a flow phantom study. The mean PBF could be measured in 6.8 min without breath-holding. RESULTS: Doppler ultrasound measurements of PBF volume were obtained reproducibly in all the healthy volunteers and were shown to correlate with the MRI values (Doppler: 12.5 +/- 3.2 cm3/s, MRI: 12.0 +/- 3.3 cm3/s; mean +/- SD). The PBF volume of patients with chronic hepatitis showed no significant difference from that of the healthy volunteers. In patients with liver cirrhosis, the PBF volume ranged from 5.01 to 32.3 cm3/s. A significant increase in PBF volume was caused in one patient by massive intrahepatic shunting and a significant decrease was caused in two patients by massive extrahepatic shunting. CONCLUSIONS: The measurement of PBF by phase contrast MRI is clinically useful in predicting intrahepatic or extrahepatic shunting in patients with liver cirrhosis, and may be of value in detecting the progression of stage in diffuse liver diseases.

Adult↗

Nucleosides and nucleotides. 121. Synthesis of oligonucleotides carrying linker groups at the 1'-position of sugar residues.

Novel 2'-deoxyuridine analogues carrying aminoalkyl linkers at the 1'-position of the sugar residues were synthesized and incorporated into oligonucleotides, then intercalating groups such as an anthraquinone derivative and a pyrene derivative were attached to the amino groups. Duplexes consisting of the oligonucleotides carrying the linker groups and a complementary ribonucleotide were more stable than an unmodified parent duplex, but the duplexes consisting of the oligonucleotides and a complementary deoxyribonucleotide were less stable. The oligonucleotides carrying the linker groups were more resistant to nuclease P1 and venom phosphodiesterase than an unmodified oligonucleotide. Furthermore, a duplex formed by the oligonucleotide analogue and the complementary ribonucleotide was a substrate for ribonuclease H.

Carbohydrate Metabolism↗

Nucleosides and nucleotides. 135. DNA duplex and triplex formation and resistance to nucleolytic degradation of oligodeoxynucleotides containing syn-norspermidine at the 5-position of 2'-deoxyuridine.

A novel 2'-deoxyuridine analogue with syn-norspermidine at the 5-position, 5-[4-[N,N-bis(3-amino-propyl)amino]butyl]-2'-deoxyuridine (1), has been synthesized from 5-iodo-2'-deoxyuridine. This nucleoside 1 was incorporated into heptadecadeoxynucleotides 5'-d[1(MT)8]-3' and 5'-[(TM)(4)1(MT)4]-3'(M = 5-methyl-2'-deoxycytidine). The triamine group stabilized duplex and triplex formation of the heptadecadeoxynucleotides with a complementary strand and a target duplex, respectively. The oligonucleotides containing 1 were more resistant to nuclease P1 and snake venom phosphodiesterase than an unmodified heptadecadeoxynucleotide, 5'-d[T(MT)8]-3'.

DNA↗

Nucleosides and nucleotides. 160. Synthesis of oligodeoxyribonucleotides containing 5-(N-aminoalkyl)carbamoyl-2'-deoxyuridines by a new postsynthetic modification method and their thermal stability and nuclease-resistance properties.

Heptadecadeoxynucleotides containing 5-(N-aminoethyl- or N-aminohexyl)carbamoyl-2'-deoxyuridines (E or H) were synthesized using a newly developed postsynthetic modification method. As a convertible nucleoside unit, 5-methoxycarbonyl-2'-deoxyuridine (1) was initially incorporated into oligodeoxynucleotides (ODNs) according to the phosphoramidite method at various positions using a DNA synthesizer. Fully protected ODNs attached to a solid support were treated with alkyldiamines such as ethylenediamine and 1,6-hexanediamine to give the above modified ODNs. The thermal stability, resistance toward nuclease digestion, and stability in fetal calf serum of the modified ODNs were studied. An increase in the number of 5-(N-aminohexyl)carbamoyl-2'-deoxyuridines (H) in the ODNs was found to effectively stabilize duplex formation with both the corresponding complementary DNA and RNA and protect against nucleolytic hydrolysis by snake venom phosphodiesterase. In particular, the half-life of ODN 19, which contained four H residues, was about 162 h in the presence of the nuclease. Furthermore, 19 was also stable in medium containing 10% fetal calf serum with a t1/2 of about 48 h, while t1/2 for the corresponding unmodified ODN was 13 min.

Deoxyuridine↗

Overexpression of p16 INK4a as an indicator for human papillomavirus oncogenic activity in cervical squamous neoplasia.

Overexpression of p16(INK4a) has been observed when retinoblastoma protein is inactivated by high-risk human papillomavirus (HPV) oncoprotein E7. We investigated overexpression of p16(INK4a) and HPV infection in cervical squamous neoplasia to evaluate the oncogenic potential among various HPV subtypes. The high-risk HPV was detected by PCR in 69.8% (37/53), 97.5% (39/40), 91.7% (44/48), and 100% (16/16) of cervical intraepithelial neoplasia (CIN)1, CIN2, CIN3, and squamous cell carcinoma (SCC), respectively. The p16(INK4a) overexpression was investigated immunohistochemically using a p16(INK4a)-specific monoclonal antibody (clone E6H4). In high-risk HPV positive cases, 32.4% (12/37) of CIN1, 82.1% (32/39) of CIN2, 93.2% (41/44) of CIN3, and all (16/16) SCC showed p16(INK4a) overexpression. The incidence of p16(INK4a) overexpression was significantly different between CIN1 and CIN2, suggesting that the disorder of cell cycle regulation by HPV frequently occurred from CIN2. As for CIN1 cases, p16(INK4a) overexpression was observed more frequently in HPV16 and HPV52 than in HPV51 and HPV35. Using p16(INK4a) as a bio marker of HPV oncogenic activity, we demonstrate that the level of pRb dysfunction by high-risk HPV varied from subtypes and was getting more frequent from CIN2.

Adult↗

The effect of cryotherapy on intraarticular temperature and postoperative care after anterior cruciate ligament reconstruction.

The objective of this study was to elucidate how cryotherapy after anterior cruciate ligament reconstruction affects intraarticular temperature and clinical results. A prospective and randomized study was performed on 21 knees of 21 patients. The ligament reconstruction was performed by single-incision arthroscopy using autogenous hamstring tendon. On completion of the surgery, thermosensors were implanted in the suprapatellar pouch and the intracondylar notch, and the intraarticular temperature was monitored while the joint was cooled. Cooling was performed in one group at 5 degrees C (N = 7) and in another at 10 degrees C (N = 7), for 48 hours. A control group (N = 7) did not undergo cryotherapy. The cooled groups showed three temperature phases: a low-temperature phase immediately after the ligament reconstruction, followed by a temperature-rising phase and a thermostatic phase. The control group had no low-temperature phase and immediately entered a thermostatic phase. During the low-temperature phase in the treated groups, the temperature of the suprapatellar pouch and of the intercondylar notch were significantly lower than the body temperature. The pain score and the number of times an analgesic had to be administered were both significantly lower in the 10 degrees C group than in the control group. Blood loss was significantly less in the 5 degrees C group than in the control group.

Adult↗

Accelerated decline of blood glucose after intravenous glucose injection in a patient with Cowden disease having a heterozygous germline mutation of the PTEN/MMAC1 gene.

The PTEN/MMAC1, a putative tumor suppressor, has been demonstrated to dephosphorylate phosphatidylinositol 3, 4, 5-triphosphate, a key molecule involved in the insulin signaling pathway. The PTEN may act, therefore, as a negative regulator of insulin signaling. The patient with Cowden disease, having a heterozygous PTEN/MMAC1 gene mutation, a C to T substitution of a single base at codon 130, was suspected to have decreased amount of PTEN protein with phosphatase signature motif. We thought that the patient might be more sensitive to insulin than normal subjects. As expected, administration of a bolus of glucose resulted in a more rapid clearance of blood glucose than was observed in 5 control subjects, indicating the presence of insulin hypersensitivity in the patient. The euglycemic hyperinsulinemic clamp study provided additional evidence.

Adult↗