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Isao Saito

Publications and source records attributed to Isao Saito.

At least 37 records · Page 2Linked to original sources
PubMed2006

[Analytical method for methoprene in foods using HPLC].

We studied the determination of methoprene in foods by high-performance liquid chromatography (HPLC). The sample was extracted with acetonitrile and the extract was salted out by adding sodium chloride, allowing the acetonitrile layer to separate. The acetonitrile solution was washed with hexane saturated with acetonitrile, cleaned up on a Florisil column and determined by HPLC. The recovery of methoprene from spiked samples was 74.6-82.8%. In an evaluation of this method by 6 analytical laboratories, mean recoveries from spiked samples ranged from 79.4% to 84.6%. Repeatability relative standard deviation values were 2.3-8.8% and reproducibility relative standard deviation values were 8.8-23.6%. The detection limits were 0.001-0.02 microg/g and below the detection limit of the Notified Analytical Method.

Chromatography, High Pressure Liquid↗
PubMed2006

[Visual prognosis of branch retinal vein occlusion with macular edema].

PURPOSE: To evaluate visual outcome and prognostic factors of branch retinal vein occlusion (BRVO) combined with macular edema, when no aggressive treatment is performed. PATIENTS AND METHODS: We retrospectively analyzed 80 eyes of 80 patients of BRVO associated with macular edema. The average age was 65.7 years and the average follow-up period was 32.1 months. Oral or instillation drug therapy was conducted in 42 eyes and peripheral scatter argon laser photocoagulation for the capillary non-perfusion area was carried out in 61 eyes (photocoagulation for macula was excluded). RESULTS: Baseline visual acuity(BVA) and final visual acuity(FVA) had a positive correlation (r= 0.60, p< 0.001). 69% of eyes with BVA of 0.1 or less remained at FVA 0.1 or worse, while 78% of eyes with BVA of 0.8 or better maintained FVA of 0.8 or better. Visual acuity improved in 26%, remained unchanged in 54%, and deteriorated in 20% during follow-up periods. In the eyes with visual loss the deterioration occurred in the early periode from onset, but in the eyes with visual improvement the visual acuity tended to improve steadily. CONCLUSIONS: Even if macular edema occurs, some of the BRVO eyes can attain good visual acuity. However, we recommend aggressive treatment when the best-corrected acuity is poor or when the visual acuity worsens gradually, because there is a strong possibility that the visual prognosis will be poor.

Adult↗
PubMed2005

Stable, specific, and reversible base pairing via Schiff base.

We here present a novel covalently linked base pair via Schiff base formation between 5-formyluracil (fU) and 5-aminocytosine (AmC). Formation of the Schiff base linkage proceeds reversibly and does not require any additives. The cross-linked DNA is very stable under denaturing conditions, whereas it completely dissociates upon heating at 90 degrees C. The pairing ability of AmC and fU is very specific and is applicable to the detection of fU, which is the major oxidative lesion of T in DNA. We propose the Schiff base linkage as a new artificial base pairing scheme to create functional DNAs.

Base Pairing↗
PubMed2005

Monitoring DNA structures by dual fluorescence of pyrene derivatives.

We have developed a nucleotide modified by a pyrene derivative with dual fluorescence. The dual fluorescence of the fluorophore, which was incorporated into DNA, was effectively controlled at ambient temperature according to DNA structural status. Our nucleoside with dual fluorescence is effective as a conceptually new probe for monitoring DNA hybridization by the color change without multilabeling with fluorescent dyes.

DNA↗
PubMed2005

Template-directed DNA photoligation via alpha-5-cyanovinyldeoxyuridine.

[reaction: see text] We describe an efficient template-directed photoligation of oligodeoxynucleotides (ODNs) using alpha-5-cyanovinyldeoxyuridine (alpha(C)U). An efficient photoligation was produced by photoirradiation of an ODN containing alpha(C)U at the 3' end with an ODN containing thymine at the 5' end in the presence of a template ODN. This photoligation method is a new and efficient way to synthesize branched ODNs.

Base Sequence↗
PubMed2005

Public-key system using DNA as a one-way function for key distribution.

Novel public-key system using DNA has been developed. To solve key distribution problem, the public-key cryptography system based on the one-way function has been developed. The message-encoded DNA hidden in dummies can be restored by PCR amplification, followed by sequencing. We used these operations as a one-way function, and constituted a novel method for the key distribution based on the public-key system using DNA. We will show the way of holding a key in common just between specific two persons.

Base Sequence↗
PubMed2005

Discrimination of single-nucleotide alterations by G-specific fluorescence quenching.

A new strategy for the detection of single-base alterations through fluorescence quenching by guanine (G) is described. We have devised a novel base-discriminating fluorescent (BDF) nucleoside, 4'PyT, that contains a pyrenecarboxamide fluorophore at the thymidine sugar's C4'-position. 4'PyT-containing oligodeoxynucleotides only exhibited enhanced fluorescence in response to the presence of a complementary adenine base. In contrast, the fluorescence of mismatched duplexes containing 4'PyT/N base pairs (N = C, G, or T) was considerably weaker. This highly A-selective fluorescence was a product of guanine-specific quenching efficiency; when the complementary base to 4'PyT was a mismatch, the pyrenecarboxamide fluorophore was able to interact intimately with neighboring G bases (the most likely interaction in the case of intercalation), so effective quenching by the G bases occurred in the mismatched duplexes. In contrast, duplexes containing 4'PyT/A base pairs exhibited strong emission, since in this case the fluorophores were positioned in the minor groove and able to escape fluorescence quenching by the G bases.

Adenine↗
PubMed2005

Predicting the pharyngeal airway space after mandibular setback surgery.

PURPOSE: The purpose of this study is to propose a mathematical model to predict the change in pharyngeal airway space (PAS) associated with mandibular setback surgery. PATIENTS AND METHODS: Twenty-three female adults, who were diagnosed as having skeletal Class III deformity, underwent mandibular setback surgery by bilateral sagittal split ramus osteotomy (BSSO) and orthodontic multibracket treatment. The subjects were assessed within 6 months before operation (T1) and 1 to 1.5 years after mandibular setback surgery (T2). The PAS change in the level of the base of the tongue was predicted. RESULTS: The equation is: PAS narrowing = 0.386 - 0.541 ANB (T1 - T2) + 0.253 Co-Gn (T1 - T2) - 0.098 SN-GoGn (T1 - T2), where ANB is the angle formed by the planes nasion-point A and nasion-point B, Co is condylion, Go is gonion, and Gn is gnathion. The PAS change can be predicted by the mandibular changes after setback surgery 66.2% with the regression equation using the change of the ANB angle, the total mandibular length (Co-Gn) and the mandibular plane (SN-GoGn), where SN is sella-nasion. CONCLUSIONS: The equation can be used to predict the change of pharyngeal airway space after mandibular setback surgery. In patients who have other risk factors, such as obesity, short neck, macroglossia, large uvula, and excessive soft tissue around the nasopharyngeal region, a mandibular setback surgery could possibly predispose to the development of sleep apnea syndrome.

Adult↗
PubMed2005

Nonsurgical treatment of adult open bite using edgewise appliance combined with high-pull headgear and class III elastics.

This case report describes the effect of a combination of high-pull headgear and Class III elastics on the nonsurgical treatment of an adult open bite. The 19-year 1-month-old Japanese female presented with the anterior open bite of 4.0 mm and mild crowding. She had a skeletal Class II but a Class III molar relationship due to a severe proclination of the mandibular dental arch. Unilateral congenital missing premolars caused a discrepancy between the facial and dental midline. After extraction of two premolars and the impacted mandibular third molars, nonsurgical therapy was performed using the standard edgewise appliance combined with a high-pull headgear and Class III elastics. The successful treatment outcome and stability of the final occlusion indicates that a combination of high-pull headgear and Class III elastics is one of the effective devices in the nonsurgical treatment of open bite and, is especially helpful in uprighting the mandibular dental arch.

Adult↗
PubMed2005

Anchorage effects of a palatal osseointegrated implant with different fixation: a finite element study.

The purpose of this study was to compare the anchorage effect of the osseointegrated implant with different fixation types using finite element analysis. Three fixation types were investigated. fixation type 1: implant neck in the oral-palatal cortical bone and implant tip in the cancellous bone; fixation type 2: implant neck in the oral-palatal cortical bone and implant tip in the nasal-palatal cortical bone; fixation type 3: implant neck in the oral-palatal cortical bone and implant tip projecting into the nasal cavity. Three finite element models were constructed. Each consisted of two maxillary second premolars, their associated periodontal ligament (PDL), alveolar bones, palatal bone, palatal implant, and a transpalatal arch. Another model without an implant was used to compare with the previous models. The horizontal force (mesial five N, palatal one N) was loaded at the buccal bracket of each second premolar. The stress was calculated in the PDL and implant surrounding bone. The result showed that the palatal implant could significantly reduce von Mises stress (maximum von Mises stress was reduced 30%) and evenly distribute stress in the PDL. The stress magnitude and distribution in the PDL was almost the same in the three implant models. These results suggest that different implant fixation types have almost the same anchorage effects.

Bone Screws↗
PubMed2005

Synthesis and properties of novel base-discriminating fluorescent (BDF) nucleosides.

We designed a new type of pyrene-labeled base-discrimination fluorescent (BDF) nucleosides (Py)U, (Py)C, (8Py)A and (MePy)dA, which emitted strong fluorescence only when the bases opposite the BDF base are A, G, T and C, respectively. The DNA probes containing four different BDF bases enable us to distinguish single base alterations by simply mixing with a sample solution of target DNA.

Adenosine↗
PubMed2005

Schiff base-mediated base pairing.

We here present a novel covalently linked base pair via Schiff base formation between 5-formyluracil (fU) and 5-aminocytosine (AmC). The formation of Schiff base remarkably increases thermal stability of the duplex DNA, whereas it completely dissociates upon heating at 90 degrees C. Neither AmC nor fU produces covalent linkage with other natural bases, and thus the pairing ability of AmC and fU is very specific.

Base Pairing↗
PubMed2005

SNPs typing by base-discriminating fluorescence DNA probe.

For the development of a novel SNP typing method using BDF (base-discriminating fluorescent) nucleosides in biological samples, we examined the detection of the single base alteration in BRCA1 gene with PCR products amplified by an asymmetric PCR. A combination of PyU- and PyC-containing BDF probes clearly facilitates the discrimination of not only A/G homozygous samples but also heterozygous samples. The present SNP typing method with BDF probes is a very powerful homogeneous assay that does not require a special device or time-consuming steps.

DNA Probes↗
PubMed2005

Genotyping with hole-transporting DNA self-assembled monolayer.

High-throughput DNA sensors capable of detecting single-base mismatches are required for the routine screening of genetic mutations and disease. A new strategy for the electrochemical detection of single-base mismatches in DNA has been developed based on hole transport through DNA self-assembled monolayers. We prepared hole-transporting DNA self-assembled monolayers. Their photocurrent measurements were carried out using amperometory. Large photocurrent was observed when the DNA duplex which constituted a hole-transporting DNA self-assembled monolayer had a full-matched sequence, whereas the photocurrent for a DNA duplex containing a mismatched base pair was much smaller.

Aldehyde Dehydrogenase↗
PubMed2005

Ability of CD8+ T cell anti-feline immunodeficiency virus (FIV) activity and FIV proviral DNA load in mononuclear cells in FIV-infected cats.

We investigated the relationship between CD8+ T cell anti-feline immunodeficiency virus (FIV) activity and FIV proviral DNA load integrated in mononuclear cells. The anti-FIV activity and the proviral DNA load were correlated, and the number of proviral DNA copies was high in cats with decreased anti-FIV activity. Particularly, no anti-FIV activity was detected in the cats staged as having an acquired immunodeficiency syndrome (AIDS)-related complex or AIDS, and the number of proviral DNA copies was obviously increased compared to those in the cats in the asymptomatic stage. These results suggest that decreased anti-FIV activity destroys the control of in vivo FIV replication, which leads to an increased proviral DNA load with the progression of the clinical stage of disease.

Animals↗