Bonding of self-etch and total-etch adhesives to carious dentin.

Carious dentin is partially demineralized and contains mineral crystals in the tubules. This may permit the deeper etching of intertubular dentin but prevent resin tag formation during bonding. We hypothesize that resin adhesives will produce lower bond strengths to caries-infected and caries-affected dentin compared with normal dentin. We tested this by measuring the microtensile bond strength of a total-etch adhesive and an experimental self-etching adhesive (ABF) to caries-infected, caries-affected, and sound dentin and by correlating those results with ultrastructural observations. The bond strengths of both adhesives to sound dentin were significantly (p < 0.05) higher than those to caries-affected dentin, which, in turn were significantly (p < 0.05) higher than those to caries-infected dentin. For both adhesives, hybrid layers in caries-affected dentin were thicker but more porous than those in sound dentin. The lower bond strengths may be due to the lower tensile strength of caries-affected dentin. Clinically, this may not be a problem, since such lesions are normally surrounded by normal dentin or enamel.

Enamel tensile bond strength and morphology of resin-enamel interface created by acid etching system with or without moisture and self-etching priming system.

The purpose of this study was to estimate the effect of three types of different adhesive systems on enamel adhesion. Scotchbond Multi-Purpose (MP) as a traditional system, Single Bond (SB) as a wet-bonding system and Clearfil SE Bond (SE) and Unifil Bond (UB) as self-etching priming systems were used. Bovine enamel was treated with each system and tensile bond strength (TBS) of resin to the enamel was measured. The conditioned enamel surfaces and resin-enamel interfaces were also morphologically observed with scanning electron microscope (SEM). The mean TBS for MP, SB, SE and UB were 15.3, 13.7, 14.3 and 11.6 MPa, respectively. There was no significant difference in mean TBS among all products but the traditional system showed the most stable TBS. In SEM observations, self-etching primer created a weaker etched pattern on the enamel surface than phosphoric acid. At the resin-enamel interfaces, thick tag-like extensions penetrated into the enamel etched with phosphoric acid regardless of using the wet-bonding technique, while self-etching primer created thin lamina-like resin penetrations. These results indicate that the traditional system with phosphoric acid etching exhibits the most stable enamel adhesion although the enamel-bonding promoting abilities of these adhesive systems are equivalent to each other.

Biliary anastomotic complications in 400 living related liver transplantations.

The purpose of this study was to evaluate the cause and outcome of biliary anastomotic complications occurring after living related liver transplantation (LRLT). A database of 391 patients undergoing 400 LRLT from June 1990 to August 1998 was reviewed. The overall incidence of biliary anastomotic complications was 18.2% (71 patients). There were 45 bile leaks, 35 anastomotic strictures, and the bile duct was ligated inadvertently in 3 cases. Univariative analysis revealed that the manner of stent usage, intrapulmonary shunting, and gender of recipients were significant risk factors for leakage. Anastomotic leaks, cytomegalovirus infection, hepatic artery complications, and gender of recipients were significant risk factors for stricture. In pediatric patients older than 2 years old, ABO blood type compatibility was another risk factor for leakage and stricture. Choice of stent usage and earlier transplantation for patients with intrapulmonary shunting should reduce the rate of biliary leaks, and prophylaxis of leaks for patients with intrapulmonary shunting, and minimizing hepatic artery complications should reduce the rate of biliary stricture after LRLT. Avoidance of ABO-incompatible donors or innovative immunosuppression in ABO-incompatible transplantation should be considered in children.

Large-scale manufacturing of all four 2'-deoxynucleosides via novel strategies including a chemo-enzymatic process.

A chemical synthesis of 2-deoxyribose-1-phosphate 2 and its enzymatic conversion into purine 2'-deoxynucleosides (dNus) are shown. Besides the chemo-enzymatic process for purine dNus, a modified process for practical dC preparation is also established. Consequently, a series of practical manufacturing processes of all four dNus have been realized via novel strategies.

Effect of priming time on tensile bond strength to bovine teeth and morphologic structure of interfaces created by self-etching primers.

PURPOSE: The purpose of this study was to investigate the effect of priming time on bovine enamel and dentin adhesion promoted by self-etching primer systems. MATERIALS AND METHODS: Two commercial self-etching primer systems, Clearfil SE Bond (SE) and Unifil Bond (UB), were used. Bovine enamel and dentin were treated with each system with various priming times (5, 20, and 60 seconds), and the tensile bond strength was measured. Scanning electron microscopic (SEM) observation was also performed to examine the effect of priming time on the morphology of the resin-tooth interface. RESULTS: The tensile bond strength to enamel ranged from 10.6 to 14.3 MPa, and no statistically significant difference was detected among products or priming times. To dentin, UB showed the statistically significantly lowest tensile bond strength when primed for 5 seconds, 6.9 +/- 1.1 MPa, but there was no significant difference between the groups primed for 20 and 60 seconds, 13.5 +/- 4.1 MPa and 13.8 +/- 4.6 MPa, respectively. SE created tensile bond strengths ranging from 13.9 to 15.7 MPa and showed no effect of priming time on dentin adhesion. SEM observation revealed that resin penetrated into both enamel and dentin more deeply with extension of priming time. CONCLUSION: Priming times longer than those recommended by the manufacturers did not influence the tensile bond strength to enamel and dentin when using two commercial self-etching primers. In contrast, a shortened priming time, 5 seconds, carried a risk of decreasing dentin adhesion, although it had no adverse effect on enamel adhesion.

Comparative genomic hybridization analysis suggests a gain of chromosome 7p associated with lymph node metastasis in non-small cell lung cancer.

We analyzed the chromosomal gains and losses that occur in 30 non-small cell lung carcinomas by comparative genomic hybridization. Their chromosomal imbalances showed histological type-specific patterns in adenocarcinomas and in squamous cell carcinomas. The genetic changes in non-small cell lung carcinoma were also strongly dependent on metastasis to lymph node. The average numbers of chromosomal alterations were increased from 6.2 to 9.1 along with the presence of metastasis, and it gave rise to the increased copy number in specific chromosomes. In particular, a novel imbalance at 7p12-21 was recognized in a half of carcinoma with metastasis, although no genetic alteration was observed in 15 non-metastasizing lung carcinoma tested here.

[IFOBT-positive gastric cancer].

Among 888 patients who underwent operation or endoscopic resection for gastric cancer (1994-1998), 75 patients, who had no colorectal disease or only small polyps 5 mm or less in diameter, were positive on the immunologic fecal occult blood test (IFOBT) (the positive group). They are compared with the other 813 patients (the negative group) as to the following 6 points: symptoms, presence of anemia, depth of invasion including macroscopic appearance, location, maximum diameter of lesions, and microscopic findings. The rate of positive-IFOBT gastric cancer was 8.4%. The average blood hemoglobin concentration was significantly lower in the positive group than in the negative group. Advanced cancers, especially type 2 and 3, were significantly more frequent in the positive group than in the negative group. The size of the lesions tended to be larger in the positive group than in the negative group. There was no difference between the groups as to symptoms, location, depth of invasion and microscopic findings. In conclusion, IFOBT-positive patients who have no colorectal disease or only small polyps 5 mm or less in diameter should be recommended to undergo upper gastrointestinal endoscopy.

Effect of self-etching primers containing N-acryloyl aspartic acid on dentin adhesion.

The purpose of this study was to evaluate the feasibility of aspartic acid derivative, N-acryloyl aspartic acid (N-AAsp) when used as a self-etching primer prior to the application of a commercial bonding agent containing 10-methacryloxydecyl dihydrogen phosphate. N-AAsp was synthesized by the reaction of DL-aspartic acid and acryloyl chloride. N-AAsp can be dissolved in water up to 25 wt % and can adequately remove the smear layer. When 20 wt % N-AAsp was applied as a self-etching primer, the tensile bonding strength of resin composite to dentin doubled to 16.0 MPa compared with that of the nonetching group or the 40 wt % H(3)PO(4) etching/water rinse group. Scanning electron microscopic observations revealed that the formation of the hybrid layer at the interface between the resin composite and dentin and the thickness of the hybrid layer increased with N-AAsp concentration. The hybrid layer in the specimens treated with 20 wt % N-AAsp aqueous solution presented a uniform structure, whereas those treated with 5 wt % N-AAsp solution showed a porous structure. We conclude that 20 wt % N-AAsp aqueous solution has good potential value as a self-etching primer.

Chemical characterisation of disruptants of the Streptomyces coelicolor A3(2) actVI genes involved in actinorhodin biosynthesis.

The actVI genetic region of Streptomyces coelicolor A3(2) is part of the biosynthetic gene cluster of actinorhodin (ACT), the act cluster, consisting of six ORFs: ORFB, ORFA, ORF1, ORF2, ORF3, ORF4. A newly devised method of ACT detection with a combination of HPLC and LC/MS was applied to the analysis of the disruptants of each ORF. ACT was produced by those of ORFB, ORFA, ORF3, and ORF4. Instead of ACT, the ORF1 disruptant produced 3,8-dihydroxy-1-methylanthraquinone-2-carboxylic acid (DMAC) and aloesaponarin II as shunt products. The ORF2 disruptant gave 4-dihydro-9-hydroxy-1-methyl-10-oxo-3-H-naphtho-[2,3-c]-pyran-3-(S)-acet ic acid, (S)-DNPA. These results support our previous proposal for stereospecific pyran ring formation in the biosynthesis of ACT, most importantly suggesting that the actVI-ORF2 product would recognize (S)-DNPA as a substrate for stereospecific reduction at C-15. The disruptant of ORFA produced (S)-DNPA together with ACT, suggesting that actVI-ORFA might play a role such as stabilising the multicomponent, type II PKS complex.

A case report: tumorectomy for brain metastasis of hepatocellular carcinoma.

Described here is a rare case of an operation for brain metastasis of hepatocellular carcinoma (HCC) after hepatectomy. We admitted a 45-year-old male patient complaining chiefly of a visual field disturbance and headaches. He had undergone a hepatectomy due to HCC one year prior to hospitalization. He was diagnosed with a brain metastasis with intratumoral hemorrhage. He underwent a tumorectomy and hemorrhage excision. After the surgery, his neurological symptoms improved, and he was temporarily rehabilitated. The decision to operate in this case could be questionable because the patient already had a pulmonary metastasis. Nevertheless, we concluded that local therapy for such a brain metastatic lesion would be effective in alleviating his discomforts and improving his quality of life as long as the primary lesion was under control.

Influence of filler content and gap dimension on wear resistance of resin composite luting cements around a CAD/CAM ceramic inlay restoration.

We investigated the influence of filler content and gap dimension on the wear resistance of composite luting cement around CAD/CAM ceramic inlay restorations. Experimental hybrid dual-cured composite luting cements containing 60, 70, 72, 74 and 80 wt% of silanated barium-silica fillers were used for cementing CAD/CAM ceramic inlay into the cavity. The specimens involving inlay-cement-tooth interfaces were subjected to a three-body wear test. The relation between the interfacial gap dimension and wear loss was also investigated using 60, 70 and 80 wt% filled cements. The cements containing more than 70 wt% filler presented significantly higher wear resistance than 60 wt% filled cement. There was a positive linear relationship between gap dimension and wear loss, and the inclination of the regression line decreased with increasing filler content. These results indicated that the higher filler content of the cement increased the wear resistance and this desirable influence appeared more remarkably in the wider horizontal gap dimension.

Biliary complications in pediatric living related liver transplantation.

BACKGROUND: The goal of this study was to evaluate cause and outcome of biliary complications occurring after pediatric living related liver transplantation (LRLT). METHODS: A database of 205 pediatric patients (71 male and 134 female) undergoing 208 LRLT from June 1990 to April 1996 was reviewed. RESULTS: The overall incidence of bile duct complications was 13.9% (29 patients). There were 19 bile leaks, 7 anastomotic strictures, 8 intrahepatic biliary complications, and the bile duct was ligated inadvertently in 2 cases. Logistic regression analysis revealed hepatic artery thrombosis, ABO incompatible transplantation, intrapulmonary shunting in recipients, mode of artery reconstruction, and cytomegalovirus infection were all significant risk factors for biliary complications. CONCLUSIONS: Avoidance of ABO incompatible transplantation where possible, routine use of microvascular techniques for hepatic artery reconstruction to minimize the risk of artery thrombosis, earlier transplantation for patients with intrapulmonary shunt, and prophylaxis against cytomegalovirus infection should all reduce the rate of biliary complications after LRLT in pediatric recipients.

Recognition of human genes by stochastic parsing.

A gene finding system, GeneDecoder, based on a parsing technique using a stochastic grammar and dictionary of genetic words is introduced. The structure of human genes are expressed by a stochastic grammar and a dictionary, whose components are the genetic words consisting of genetic phonemes, built as hidden Markov models (HMMs). The HMMs represent the nucleotide acid bases, the codons, and the amino acids. The genetic words in the dictionary are described by the sequence of these HMMs and represent exons, introns, intergenic regions, tRNA regions and signals in DNA sequences. The statistics between these regions are expressed by the grammar, which is a stochastic network of the genetic words. Using the same kind of technique of speech recognition by HMMs with a word dictionary and a grammar, the stochastic network of genetic words enables the motif dictionary to be used during the parsing of the DNA sequences. At the same time, stochastic features of donor/acceptor sites, information of the di-codon statistics, and other important features are integrated into stochastic scores during the parsing. As a result, while the system parses DNA sequences and finds the exon/intron structures, the protein motifs are automatically annotated in the regions. It helps to identify the functions of the genes and reduces the cost of homology search for each hypothetical coding regions. This method is different from simply using the information of homology search. This method uses the information of the motif patterns during the parsing process, but searching the motif patterns after/before finding the coding regions cannot directly affect the parsing process itself. Experimental results have shown that this method reasonably finds and annotates the motifs in the exons in the DNA sequence of human.

[The clinical efficacy of imipenem/cilastatin sodium in orthopedic infections and drug levels in the bone tissue].

We evaluated the clinical efficacy of imipenem/cilastatin sodium (IPM/CS--a carbapenem antibiotic) against orthopedic infections, and the drug levels of the bone tissues were determined. The clinical efficacies for 6 patients in the infection group were good in 3 cases, and fair in the other 3; giving an efficacy rate of 50%. Bacteriologically, 8 strains were isolated from patients with the infection and an eradication rate of 87.5% was obtained upon the treatment. In 39 patients that were given the drug prophylactically, no postoperative infections occurred. Mean IPM levels in the bone and the bone marrow at 1 hour after administration in 5 patients of the prophylactic group were 17.3 micrograms/ml and 5.9 micrograms/g, respectively. The ratio of concentrations the bone to those in the bone marrow was 34.6%. The results of this study suggest that IMP/CS reaches to the bone tissue providing sufficient concentrations and that the drug is efficacious for the prophylaxis and the treatment of orthopedic infections.

Automatic Gene Recognition without Using Training Data.

In this paper, we propose a new approach for gene recognition, which uses no training data for the recognizer. In this approach, we start from a simple model, which only uses the knowledge of start codons and the stop codons, then the recognition of the DNA sequences by the recognizer and the training of the parameters of the recognizer by the result of the recognition are repeated. We applied this parse and train approach to the complete genome sequence of cyanobacterium, and achieved the almost same recognition rate with the case of using the whole sequence as training data. This results open the possibility to use automatic gene annotation system in the early stage of sequencing projects.

[Detection of the thermostable lipase gene (lipAH) in clinical isolates of Aeromonas hydrophila belonging to the major O serogroups O11, O16 and O34].

On the basis of DNA hybridization data and phenotypes, most pathogenic strains of Aeromonas hydrophila are grouped into hybridization group 1 (HG1). These pathogenic strains secret the theromostable lipase, and it's gene (lipAH) has been cloned and sequenced. The present study was performed to identify the pathogenic strains of A. hydrophila by the polymerase chain reaction (PCR) technique to detect the lipAH. Synthetic oligonucleotide primers (lipAH-ns-1 and -na-1) were used in the PCR. The PCR identified 80% of lipAH-positive strains, consisting of seven of the 11 O11 strains (64%), 13 of the 15 O16 strains (87%) and 25 of the 30 O34 strains (83%) in clinical isolates of A. hydrophila used in this study.

[Use of the the ED046 kit to analyze serum KL-6 in patients with pneumonitis].

KL-6 is a mucinous glycoprotein expressed on Type 2 pneumonocytes, and serum levels of KL-6 are reported to be abnormally high in patients with interstitial pneumonia. A new assay kit for serum KL-6 (ED046) was used in the evaluation of patients with pneumonitis. To clarify whether KL-6 is a useful marker of pneumonitis activity, 649 subjects were studied, including 185 healthy controls, 187 patients with 3 types of interstitial lung diseases, and 277 patients with 4 types of non-interstitial lung diseases. The serum KL-6 level was significantly higher in the patients with pneumonitis (1285 +/- 1196 U/ml) than in the patients without pneumonitis (307 +/- 232 U/ml). The KL-6 level was also significantly higher in patients with clinically active pneumonitis (1708 +/- 1338 U/ml) than in those with inactive pneumonitis (820 +/- 796 U/ml) (p < 0.0001). Serum KL-6 levels correlated significantly with serum c-reactive protein, lactic dehydrogenase, and PaO2 values. These results suggest that the ED046 assay is useful for measuring KL-6 as a marker of pneumonitis activity.

[Four important subjects of successful care at home for patients of terminally ill].

From April 1987 to May 1995, we have had care at home for 103 patients of terminally ill, and at this through our experience, we pointed out four important subjects for successful care at home. The first is prompt consultation at anytime when the patient or its family need. It is especially important when the patient's end time is near and previously we must fully instruct to patient's family how to consult and how to care. The second is effective palliative care. In these palliative care pain control with morphine is most important and we must master how to use morphine. The third is truth telling and informed consent. At treatment we have to communicate true information to patient. Home care must be started under patient's will. The fourth is organization of medical care, health care and welfare care. We have to make up network system of these office at first, and finally we have to make up community for supporting patients and these family.

Spontaneous aortic arteriosclerosis in layer chickens.

Aortas of 21 grower chickens (both sexes) aged 30-130 days and of 51 layer hens aged 500 days were examined histopathologically. Aortic sclerotic lesions were classified histopathologically into six stages. As early as 30 days, the abdominal aortas of growers had cellular-fibrous plaques that became more severe with advancing age. The majority of the abdominal aortas of all the 500-day-old layers had a conspicuous increase of collagen fibres, with atheromatous lesions in 23 (45.1%). These sclerotic changes were most severe in the distal aortas.