Effect of methanol and water contents on production of biodiesel fuel from plant oil catalyzed by various lipases in a solvent-free system

Methyl esters synthesized from plant oil and methanol by the methanolysis reaction are potentially important as a biodiesel fuel. The methanolysis of soybean oil by lipases from various microorganisms was investigated. Several of the lipases were found to catalyze methanolysis in a water-containing system without an organic solvent. The lipases from Candida rugosa, Pseudomonas cepacia, and Pseudomonas fluorescens displayed particularly high catalytic ability. The reaction rates of methanolysis catalyzed by the C. rugosa and P. fluorescens lipases decreased significantly when the water content was low, showing that water prevents the inactivation of these lipases by methanol. On the other hand, the methanolysis reaction rate catalyzed by the P. cepacia lipase remained high even under a low water content. In addition, the P. cepacia lipase gave high methyl ester contents in the reaction mixture up to 2 or 3 molar equivalents of methanol to oil, which is attributed to the P. cepacia lipase having substantial methanol resistance. For the same methanol content, the reaction rates of methanolysis catalyzed by the P. cepacia lipase increased with decreasing water content, and hence lipases strongly resistant to high methanol, such as that from P. cepacia, are desirable for use in methanolysis reaction processes.

Immune response to surface protein A of Streptococcus pneumoniae and to high-molecular-weight outer membrane protein A of Moraxella catarrhalis in children with acute otitis media

The immune response was evaluated in 11 children with Streptococcus pneumoniae and in 9 children with Moraxella catarrhalis otitis media. The age of the children had a range of 4-32 months. The mean IgG, IgM, and IgA antibody responses to surface protein A (PspA) of S. pneumoniae in sera from children at the acute and convalescent stages were 4864 versus 5831 ng/mL, P<.05, 1075 versus 3752 ng/mL, P<.05, and 67 versus 93 ng/mL, nonsignificant (NS), respectively. The mean IgG, IgM, and IgA antibody responses to the high-molecular-weight outer membrane protein (UspA) of M. catarrhalis in sera from children at acute and convalescent stages were 710 versus 935 mg/mL, NS; 1895 versus 2646 ng/mL, NS; and 121 versus 204 ng/mL, P<.05, respectively. These data show that PspA and UspA are immunogenic in children after otitis media.

Immune responses to specific antigens of Streptococcus pneumoniae and Moraxella catarrhalis in the respiratory tract

Streptococcus pneumoniae and Moraxella catarrhalis are two common respiratory pathogens, colonizing as many as 54 and 72% of children, respectively, by 1 year of age. The immune responses to surface protein A of S. pneumoniae (PspA) and the high-molecular-weight outer membrane protein of M. catarrhalis (UspA) in the sera of various age groups in the general population and in the nasopharynges of 30 children monitored from birth through 1 year of age were evaluated. Immunoglobulin G (IgG) was the dominant serum antibody to PspA and UspA. Whereas the serum antibody response to PspA peaked in childhood, the antibody response to UspA peaked in adulthood. In the first 2 years of life, comparable amounts of IgM and IgG antibodies to both proteins were observed. In older persons, IgG antibodies to both antigens predominated over IgM antibodies. The levels of IgA antibody to these antigens in serum remained low during the first 2 years of life. The levels of IgM antibody to the two antigens in serum exceeded the levels of IgA antibody to the same two antigens throughout life. Although IgA was the dominant antibody to PspA and UspA in airway secretions, it was detected in a minority of the children (3 of 15 for PspA and 0 of 15 for UspA). Even the majority of the children previously colonized with these pathogens lacked antibody to them in their secretions.

Pretreatment of immobilized Candida antarctica lipase for biodiesel fuel production from plant oil

The effects of the pretreatment of immobilized Candida antarctica lipase enzyme (Novozym 435) on methanolysis for biodiesel fuel production were investigated. Methanolysis progressed much faster when Novozym 435 was preincubated in methyl oleate for 0.5 h and subsequently in soybean oil for 12 h. The initial reaction rate of methanolysis catalyzed by both the non-treated and preincubated enzyme decreased significantly with increasing water content. The initial reaction rate increased with increasing methanol content, showed a maximum, and thereafter decreased when the methanol content was increased further. The variation of the initial reaction rate with the methanol content was therefore analyzed using a Michaelis-Menten-type equation with substrate inhibition. Based on this equation, a procedure for the stepwise addition of methanol to the reaction mixture so as to maintain the desired methanol content was determined. When preincubated Novozym 435 was used, the ME content reached over 97% within 3.5 h by stepwise addition of 0.33 molar equivalent of methanol at 0.25-0.4 h intervals.

Biodiesel fuel production from plant oil catalyzed by Rhizopus oryzae lipase in a water-containing system without an organic solvent

A new enzymatic method of synthesizing methyl esters from plant oil and methanol in a solvent-free reaction system was developed. It is anticipated that such plant oil methyl esters can be used as a biodiesel fuel in the future. Lipase from Rhizopus oryzae efficiently catalyzed the methanolysis of soybean oil in the presence of 4-30 wt% water in the starting materials; however the lipase was nearly inactive in the absence of water. The methyl ester (ME) content in the reaction mixture reached 80-90 wt% by stepwise additions of methanol to the reaction mixture. The kinetics of the reaction appears to be in accordance with the successive reaction mechanism. That is, the oil is first hydrolyzed to free fatty acids and partial glycerides, and the fatty acids produced are then esterified with methanol. Although R. oryzae lipase is considered to exhibit 1(3)-regiospecificity, a certain amount of 1,3-diglyceride was obtained during the methanolysis and hydrolysis of soybean oil by R. oryzae lipase solution. Therefore, the high ME content in the reaction mixture is probably attributable to the acyl migration from the sn-2 position to the sn-1 or sn-3 position in partial glycerides.

[Identification of penicillin-resistant Streptococcus pneumoniae in nasopharynx of patient with acute otitis media by PCR]

Streptococcus Pneumoniae is a leading cause of acute otitis media (AOM). For most AOM caused by S. pneumoniae, penicillin is the antibiotic of choice. However, there are some recent reports of clinical resistance to penicillin by S. pneumoniae. The sequences of penicillin binding protein, pbpla, pbp2b and pbp2x, genes of penicillin-resistant S. pneumoniae (PRSP) were more highly divergent than those of penicillin-succeptible S. pneumoniae (PSSP). The polymerase chain reaction (PCR) can easily determine whether an S. pheumoniae isolate is susceptible or resistant to penicillin by amplifying the target gene by using a combination of primers. In this study, clinical isolates (n = 12) were obtained from the nasopharynx of patients with AOM. PCR was used to confirm the identification of an isolate as S. pneumoniae by amplifying the autolysin gene and to detect three PBP genes by amplifying parts of pbp1a, pbp2x and pbp2b. The resistance of S. pneumoniae to penicillin and other beta-lactams has been shown to be associated with mosaic mutations in the pbp1a, pbp2b and pbp2x genes. These findings suggest that rapid identification of PSSP and PISP/PRSP by PCR is possible and very useful for proper treatment of acute otitis media.

Interleukin-8 in otitis media with effusion

Interleukin-8 induces chemotaxis of neutrophils, basophils and T-lymphocytes, releases intracellular enzymes from neutrophils and histamine from basophils, and regulates the adhesion of neutrophils. In this study, using an enzyme-linked immunosorbent assay, we evaluated 33 middle ear effusions (MEEs) for levels of IL-8. The mean level of IL-8 in MEEs from children with OME was 616.7 +/- 211.0 pg/mgTP, while that of adults was 197.4 +/- 66.7 pg/mgTP. With respect to MEE types, the mean level of IL-8 in serous effusion was lower than that in two other types of MEEs (mucoserous and serous). These results suggest that inflammatory reaction in the middle ear cavity of children with OME is different from that of adults and that the pathogenesis of OME in children may differ from that in adults. Determination of IL-8 concentration in MEEs may help to illuminate the pathogenesis of OME.

[Characterization of cell lines from metastatic maxillary cancer]

Two cell lines were established one from a primary site (OKK-TKp) and the other from a metastatic lymph node (OKK-TKm), from a maxillary squamous cell carcinoma (in the same patient). These cell lines were characterized with regard to morphology, chromosome numbers, tumorigenicity, growth kinetics, expression of tumor markers, sensitivity to immunological effector cells and anticancer agents. The two cell lines had the same modal chromosome number of 69, and formed tumors in nude mice. The median doubling time of OKK-TKp was 14.6 hrs and that of OKK-TKm was 24.3 hrs. Immunohistochemistry showed transferrin receptor (TfR), Ki-67, and epidermal growth factor receptor (EGFR) in OKK-TKm, but less or none in OKK-TKp. OKK-TKm was more sensitive to lysis by lymphokine-activated killer cells (LAK) on a 4-h 51Cr release assay, but was less sensitive to anticancer agents (CDDP, CBDCA) in modified MTT assay. We are convinced that these results are of value for understanding the mechanism of metastasis.

Analysis of viral infection in patients with IgA nephropathy

We investigated viral infections in the tonsils, pharynx and renal tissues of patients with IgA nephropathy using cell culture, polymerase chain reaction (PCR) and immuno-fluorescent techniques, and measured antibody titers against numerous types of viruses. Neutralization tests found no significant inhibition of growth of adenovirus-1, 2, 3, 4, 5, 6, 7, 11 or 19, Coxsackie virus-A7, A9, A16, B1, B2, B3, B4, B5 or B6, or RS virus. Swabs of the oral cavity of patients with IgA nephropathy were cultured with Hel cells, MDCK cells, FL cells, BHK-21 cells and RD-18S cells. No cytopathic effect was detected in any of these cell cultures. We failed to detect the presence of herpes simplex virus-1 and -2, varicella-zoster virus, cytomegalovirus and Epstein-Barr virus (EBV)-1 and -2 in tonsils, renal tissues and mouthwashings from patients with IgA nephropathy. On the other hand, EBV alone was detected with the PCR technique, in mouthwashings from 6 out of 14 patients with IgA nephropathy (42%). Immunohistological and serological analyses were done to examine the relationship between EBV and IgA nephropathy. No evidence was obtained that EBV-infected B lymphocytes were producing IgA. It seems unlikely that the viral infections examined in this study play a significant role in the pathogenesis of IgA nephropathy.

[Expression of HLA-DR antigen on head and neck carcinomas--immunohistological study]

We investigated the expression of HLA-DR antigen on 42 squamous cell carcinomas of head and neck using immunohistological methods. Our results indicate significant relationships between HLA-DR antigen expression on carcinomas and lymphocytic infiltration, that is, CD8 positive lymphocytes (CD8/CD3) infiltrated HLA-DR antigen positive carcinomas while CD4 positive cells (CD4/CD3) were found in HLA-DR negative carcinoma. The Ki-67 (a nuclear marker of proliferation) positive rate was lower on HLA-DR positive carcinomas than on negative carcinomas. However, there was no correlation with pathological differentiation, clinical stage or primary lesion. In vitro studies using several cytokines showed that IFN-gamma induced expression of HLA-DR antigen and lowered the Ki-67 positive rate on squamous cell carcinomas. It seems that HLA-DR antigen expression on squamous cell carcinomas could be induced by cytokines released from the infiltrating lymphocytes.

[Study of the duration of antimicrobial chemotherapy in mycoplasmal pneumonia]

We assessed the period of administration of antibiotics required for cases of mycoplasmal pneumonia. The subjects were 38 patients with mycoplasmal pneumonia admitted to our hospital. These patients were treated with 100 mg minocycline or 500 mg erythromycin by intravenous infusion twice a day. They were divided into a 6 day-administration group (Group A; 16 cases) and a 9 day-administration group (Group B; 17 cases). Administration was discontinued on the 4th day or earlier in 5 cases due to side effects. A comparative assessment was made between Groups A and B with respect to body temperature, WBC, erythrocyte sedimentation rate, CRP, and chest X-ray on the 3rd, 6th, and 9th days of treatment, but no significant difference was observed. Residual shadows at the end of treatment were present in 100% of Group A and in 47% of Group B, but they disappeared gradually in both groups. No cases of recurrence were observed in either Group A or B within 1 month after the completion of treatment. Regarding the treatment period for mycoplasmal pneumonia by intravenous infusion of minocycline or erythromycin, no significant clinical difference was observed between the 6 day-administration group and the 9 day-administration group, suggesting that 6 days of administration is sufficient for treatment.

[Tree pollens and nasal allergy (XI). Relationship of age to the total IgE level, Japanese cedar RAST score, Japanese cedar-specific IgG antibodies and IgG subclass]

Japanese cedar pollinosis occurs most frequently in the twenties and thirties. To understand this phenomenon, total serum IgE, frequency of positive RAST reactions to Japanese cedar and Japanese cedar-specific IgG antibody were examined in serum samples from a general population consisted of 1,491 subjects and their age-related changes were investigated. The difference of mean value of total serum IgE was not significant between age groups. Positive RAST's to Japanese cedar were found in 13.9% of cases. The frequency of positive RAST reactions showed a peak in the twenties and decreased thereafter with aging. The amount of Japanese cedar-specific IgG antibodies was 244.7 +/- 373.2 GRU/ml (mean +/- S.D.) and there was no significant difference between males and females. There was no difference in the amount of specific IgG antibodies among the subjects giving RAST scores of 0-3, whereas those giving RAST scores of 4 had lower specific IgG antibodies. The amount of Japanese cedar-specific IgG antibodies increased from the fifties. Specific antibody of IgG1 subclass to Japanese cedar increased with age, whereas IgG4 antibody increased slightly without statistically significant difference. Based on the above result, we discussed why Japanese cedar pollinosis occurs most frequently in the twenties and thirties.