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1.
J Oleo Sci ; 62(3): 123-32, 2013.
Article in English | MEDLINE | ID: mdl-23470439

ABSTRACT

Hydrogen bonding between surfactant molecules plays an important role in self-assembly formation. For long alkyl chain amine oxide surfactants, the specific protonation degree dependence of some solution properties has been considered to be due to hydrogen bonding between protonated and deprotonated species. In addition to this type of hydrogen bonding, we introduced a pyridyl group into an alkylamine oxide molecule as a new hydrogen-bonding site. The pyridyl group has three different structural isomers based on the position of the substituent. An amine oxide group in pyridylamine oxides was preferentially protonated. In addition, protonation of the pyridyl group revealed a pronounced substituent position effect on the critical micelle concentration, micellar size, and solubilization of oil-soluble dye into micelles. The intermolecular or intramolecular hydrogen bond formation could be controlled by altering the substituent position.


Subject(s)
Amines/chemistry , Oxides/chemistry , Pyridines/chemistry , Surface-Active Agents/chemistry , Hydrogen Bonding , Molecular Structure , Protons , Solutions
2.
Adv Colloid Interface Sci ; 88(1-2): 275-93, 2000 Dec 11.
Article in English | MEDLINE | ID: mdl-11185701

ABSTRACT

The effects of protonation on alkyldimethyl amine oxide micelles are reviewed, mainly with regard to dodecyl and tetradecyl homologs. The topics discussed are hydrogen ion titration properties, critical micelle concentration (CMC), area per surfactant and micelle aggregation number. A hydrogen bond hypothesis is proposed to interpret the several characteristic results associated with protonation: between two cationic species as well as between the non-ionic-cationic pair. The dipole-dipole interaction of the non-ionic micelle is discussed in relation to both: (a) the unusually high CMC values of the non-ionic micelles compared with other non-ionic surfactants with the same hydrocarbon chain; and (b) the reversal of the stability of the non-ionic and the cationic micelles at high ionic strengths. Two different approaches of the salting out effect on the ionic micelles are compared, the Chan-Mukerjee approach and ours, in relation to the non-linear Corrin-Harkins relation. The obtained salting out constants of the surfactants carrying a dodecyl chain decreased as the head group becomes more polar. Infrared and 13C-NMR spectra data are examined from the point of the specific interaction claimed by the hydrogen bond model. Mixed surfactant systems including amine oxides and the solid state phase behavior of amine oxides are both briefly reviewed.

3.
J Colloid Interface Sci ; 197(2): 309-16, 1998 Jan 15.
Article in English | MEDLINE | ID: mdl-9466872

ABSTRACT

Critical micelle concentrations (cmc) of dodecyldimethylamine oxide (DDAO) were determined at 25°C in solutions in the absence of salt at different pH values by four methods: surface tension, dye solubilization (Sudan III), pH-concentration break points, and counterion (Cl-) activity. With the aid of the cmc values, the degree of ionization of DDAO micelle alphaM was determined as a function of pH from the hydrogen ion titration. The cmc increased sharply in a narrow range of alphaM from 0.35 to 0.40. This destabilization of micelles was also noted on the anomalous change of pK on the hydrogen ion titration curve. The counterion activity was measured potentiometrically, and the degree of the counterion binding theta was determined as a function of alphaM. The value of theta showed a sharp increase with alphaM also around 0.4. The line width of NMR absorption peak of 35Cl ions was well correlated with alphaM. The surface electric potentials psi0 of DDAO micelles were evaluated from both the hydrogen ion titration and the acid-base indicators, and the former value was larger than the latter one. A procedure is proposed to compare the stabilities of the micelles having different alphaM values. The result indicates much larger dependences on alphaM than those uncorrected for different ionic strengths at the cmc. Copyright 1998 Academic Press. Copyright 1998Academic Press

4.
Nihon Rinsho ; 52(1): 40-4, 1994 Jan.
Article in Japanese | MEDLINE | ID: mdl-8114308

ABSTRACT

In patients with liver cirrhosis, there were various symptoms in decompensated state, but not in compensated state. Most of symptoms were due to liver cell dysfunction and portal hypertension. Jaundice, ascites, edema, bleeding tendency and endocrinological symptoms were due to liver cell dysfunction. Hepatic encephalopathy, esophageal varices and splenomegaly were related to portal hypertension. Vascular spiders and palmar erythema were found in patients with alcoholic liver cirrhosis more frequently than in patients with viral liver cirrhosis. Jaundice was a sign of poor prognosis. There were no difference in clinical symptoms between aged patients and young patients. Careful observation of the symptoms is important to care the patients with liver cirrhosis.


Subject(s)
Liver Cirrhosis/physiopathology , Adult , Aged , Esophageal and Gastric Varices/etiology , Female , Hepatic Encephalopathy/etiology , Humans , Hypertension, Portal/complications , Liver Cirrhosis/diagnosis , Liver Cirrhosis/etiology , Liver Failure/complications , Male , Middle Aged
5.
Nihon Rinsho ; 52(1): 45-9, 1994 Jan.
Article in Japanese | MEDLINE | ID: mdl-8114309

ABSTRACT

In patients with liver cirrhosis, there were many abnormalities in laboratory tests. Serum GOT, GPT and LDH were elevated due to the liver cell necrosis. The value of ICG tests reflected the decrease of effective hepatic blood flow and the increase of intrahepatic shunt flow. White blood cell counts and the number of platelet were decreased due to the hypersplenism. Serum albumin and cholineesterase levels were decreased more remarkably in patients with alcoholic liver cirrhosis than in patients with viral liver cirrhosis. Raised GOT and GPT levels were lower in aged patients than in young patients. Serial laboratory tests were important for the management of patients with liver cirrhosis.


Subject(s)
Hematologic Tests , Liver Cirrhosis/diagnosis , Aged , Alanine Transaminase/blood , Aspartate Aminotransferases/blood , Female , Humans , L-Lactate Dehydrogenase/blood , Liver Circulation , Liver Function Tests , Male , Middle Aged
6.
Hepatology ; 18(6): 1319-25, 1993 Dec.
Article in English | MEDLINE | ID: mdl-8244255

ABSTRACT

We quantified serum hepatitis C virus RNA titers and determined hepatitis C virus subtypes in chronic hepatitis C patients treated with interferon-beta to investigate relationships among serum ALT response, serum hepatitis C virus titer and hepatitis C virus subtype. Of 146 chronic hepatitis C patients who received interferon-beta therapy, 24 patients with sustained serum ALT normalization (complete responders) and 26 patients without serum ALT normalization (nonresponders) were randomly selected. Detection, typing and quantitation of hepatitis C virus were performed by means of the "single-tube" polymerase chain reaction method. Of the 24 complete responders, 21 (87.5%) became negative for hepatitis C virus RNA, whereas 21 (80.8%) of the 26 nonresponders remained positive. Hepatitis C virus infections with types I, II, III, IV, II + III and III + IV occurred in 0 (0%), 22 (51.2%), 10 (23.3%), 1 (2.3%), 7 (16.5%) and 3 (7.9%) patients, respectively. The mean pretreatment hepatitis C virus RNA titer of complete responders (0.4 +/- 2.0 x 10(4) CID50/ml) was significantly lower than that of nonresponders (3.8 +/- 4.5 x 10(4) CID50/ml) (p < 0.01). Regardless of HCV subtype, patients with more than 10(4) CID50/ml of HCV did not show serum ALT normalization, whereas complete serum ALT response was seen in most cases with less than 10(2) CID50/ml HCV. These results show that mixed infections with different hepatitis C virus subtypes appear to be more common than previously reported and that the pretreatment serum level of hepatitis C virus RNA is a more important predictor of outcome of interferon therapy than is virus genotype.


Subject(s)
Hepacivirus/classification , Hepatitis C/therapy , Interferon-beta/therapeutic use , RNA, Viral/blood , Adult , Aged , Alanine Transaminase/blood , Chronic Disease , Female , Hepacivirus/genetics , Hepacivirus/isolation & purification , Hepatitis C/enzymology , Hepatitis C/microbiology , Humans , Male , Middle Aged , Polymerase Chain Reaction/methods , Prognosis
7.
Intern Med ; 32(7): 523-9, 1993 Jul.
Article in English | MEDLINE | ID: mdl-8286827

ABSTRACT

The antiviral effect of natural interferon (IFN)-alpha on chronic hepatitis C virus (HCV) infection was estimated by determining quantitative changes in serum HCV-RNA compared with the serum alanine aminotransferase (sALT) improvement; the relationships of responses to IFN according to the dose and period of IFN therapy were defined to determine an appropriate IFN therapy protocol. Twenty-two patients with chronic hepatitis C were given natural IFN-alpha and in 16 (72.7%) patients the viraemia was suppressed during therapy. Five (27.7%) of them sustained the disappearance of HCV-RNA for more than 6 months after therapy accompanied with a prolonged sALT improvement. Pre-treatment viraemia levels in 5 complete responders with "complete suppression" of viraemia were significantly lower than in 11 patients with a transient loss or a decline of HCV-RNA. A favorable antiviral response was closely associated with a high total dose of IFN-alpha and a long duration of IFN therapy.


Subject(s)
Hepacivirus/isolation & purification , Hepatitis C/therapy , Immunologic Factors/therapeutic use , Interferon-alpha/therapeutic use , RNA, Viral/blood , Viremia/therapy , Adult , Alanine Transaminase/blood , Base Sequence , Female , Hepatitis C/blood , Hepatitis C/enzymology , Hepatitis, Chronic , Humans , Male , Middle Aged , Molecular Sequence Data , Treatment Outcome , Viremia/enzymology , Viremia/microbiology
8.
J Hepatol ; 16(1-2): 138-44, 1992 Sep.
Article in English | MEDLINE | ID: mdl-1336504

ABSTRACT

To evaluate the effect of interferon-alpha treatment on the levels of serum aminotransferase (sALT) and of hepatitis C virus (HCV)-RNA, we studied 19 patients with chronic non-A, non-B (NANB) hepatitis. Before therapy, 14 patients were positive by nested polymerase chain reaction (PCR) with primers deduced from the 5'-non-coding region of the HCV genome. Serum HCV-RNA had disappeared in 12 (85.7%) of them by the end of therapy, but then reappeared 6 months later in 4 of these 12 patients. A marked improvement in sALT was seen in 5 of the 8 patients with sustained HCV-RNA disappearance, but not in the 4 patients with only transient HCV-RNA negativity. Pre-treatment levels of hepatitis C viremia, analyzed by single PCR and dot blot hybridization, ranged from 2 x 10(3) to 2 x 10(8) copies/ml, and were below 2 x 10(5) copies/ml in patients with a complete response to interferon therapy. These results suggest that this HCV-RNA assay, combined with sALT testing, may be useful for estimation of the long-term efficacy of interferon therapy in hepatitis C.


Subject(s)
Hepacivirus/isolation & purification , Hepatitis C/therapy , Interferon-alpha/therapeutic use , RNA, Viral/analysis , Adult , Base Sequence , Female , Hepatitis C/microbiology , Humans , Male , Middle Aged , Molecular Sequence Data , Nucleic Acid Hybridization , Polymerase Chain Reaction
9.
Kansenshogaku Zasshi ; 64(12): 1561-5, 1990 Dec.
Article in Japanese | MEDLINE | ID: mdl-2074375

ABSTRACT

Although bacteremia caused by non-typhoidal salmonella is frequently observed in immunocompromised hosts, it is rare to find this condition in healthy subjects. In this report, we present a case of bacteremia due to Salmonella enteritidis detected in a healthy man. A 59-year-old man was admitted to our hospital with a fifty-day history of fever on May 18, 1985. On admission, he showed no symptoms except high body temperature (38.8 degrees C). In the laboratory data, C-reactive protein was 3+, white- cell count was 9600, and erythrocyte sedimentation rate was 12 mm/h. Culture in blood and stool yielded Salmonella enteritidis. However, no abnormal findings were found in UGIS, barium enema, OC + DIC, abdominal CT and echography. As soon as Ampicillin was administered, the fever was gone and the blood culture yielded nothing. After six months, the stool culture was negative for pathological intestinal bacterial flora and he was in good physical condition. Generally, bacteremia develops mainly in the immunocompromised hosts, such as patients with neoplastic disease, AIDS, leukemia or collagen disease. The literature provides so far twenty three adult cases of bacteremia due to non-typhoidal salmonella in Japan. Only two of them had no systemic disease as well as our case. Although it is unknown why bacteremia developed in this healthy man, we reported that bacteremia developed rarely in subjects with healthy condition.


Subject(s)
Salmonella Infections , Salmonella enteritidis , Sepsis/microbiology , Humans , Male , Middle Aged
10.
Hepatogastroenterology ; 37 Suppl 2: 126-9, 1990 Dec.
Article in English | MEDLINE | ID: mdl-2128073

ABSTRACT

Serum DNA polymerase activity (DNA-P) was detected in 27.6 per cent of non-A, non-B (NANB) hepatitis patients, 8.7 per cent of patients with alcoholic liver disease (ALD), 8.6 per cent of hepatitis B surface antigen (HBsAg)-positive patients and 19.0 per cent of HBsAg-negative blood donors with elevated serum glutamic-pyruvic transaminase (SGPT) concentrations. In contrast, none of the patients with hepatitis A, drug-induced liver injury or non-alcoholic fatty liver had DNA-P in their sera in the acute phase of the illness. All HBsAg-positive samples with detectable DNA-P were strongly positive for hepatitis B virus (HBV) DNA, but the samples from patients with NANB hepatitis and ALD and HBsAg-negative blood donors had no HBV DNA. Sensitivity to actinomycin D showed the heterogeneity of DNA-Ps in HBsAg-negative blood donors; the enzyme activity of one type was inhibited by 100 micrograms/ml of actinomycin D, whereas the other was not. The preference for exogenous template primers of these DNA-Ps was different to those of HBV and human retroviruses. The results reveal the prevalence of serum DNA-P in NANB hepatitis patients and suggest that two distinct agents are relevant to the aetiology of NANB hepatitis.


Subject(s)
Alanine Transaminase/blood , Blood Donors , DNA-Directed DNA Polymerase/blood , Hepatitis C/enzymology , Hepatitis B Surface Antigens/blood , Humans , Liver Diseases/enzymology
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