TDAG51 is not essential for Fas/CD95 regulation and apoptosis in vivo

Fas/CD95 is a key regulator of apoptotic signaling, which is crucial for the maintenance of homeostasis in peripheral lymphoid organs. TDAG51 has been shown to play critical roles in the up-regulation of Fas gene expression and T-cell apoptosis in vitro. In order to identify the role of TDAG51 in vivo, we generated TDAG51-deficient (TDAG51-/-) mice. Northern blotting revealed no expression of TDAG51 in TDAG51-/- mice, indicating that the TDAG51 gene was successfully targeted. TDAG51-/- mice were healthy and showed no gross developmental abnormalities. While Fas-deficient mice display marked lymphadenopathy, splenomegaly, and lymphocytosis, TDAG51-/- mice had no apparent defects in secondary lymphoid organs. Although TDAG51 is required for up-regulation of Fas expression in T-cell hybridomas, TDAG51-/- mice expressed normal levels of Fas and had normal T-cell apoptosis. Therefore, we conclude that TDAG51 is not essential for Fas up-regulation and T-cell apoptosis in vivo. There are several known homologs of TDAG51, and these homologs may substitute for TDAG51 in TDAG51-/- mice.

[A new lymph-node staging system for gastric cancer]

OBJECTIVE

To evaluate the predictive effects of the new lymph node staging system based on the ratio of the number of metastatic lymph nodes to the total number of dissected lymph nodes comparing with N-staging of the 5th TNM (UICC, 1997).

METHODS

Lymph nodes harvested from operative specimens in 78 patients with gastric cancer were examined histologically. pN staging was carried out according to the two staging systems respectively. In our system, pN0, pN1, pN2, pN3 were defined as lymph node ratio(LNR) 0, <10%, <25% and >25%, respectively. All the patients were followed up and the data were analyzed statistically.

RESULTS

A total of 5388 lymph nodes were found with a mean of 69 per case (range 30-157). Lymph node metastases were detected in 59 patients (75.64%). The 3-year survival rates of pN0, pN1, pN2, pN3 of the new staging system were 100%, 68.42%, 7.58% and 6.78%, respectively.

CONCLUSION

The lymph node ratio is a relative variable, which reflects the degree of metastasis of lymph node, and is more predictable than the UICC 1997 5th N-staging system defined as the numbers of metastatic lymph node.

[An analysis of the results of central masking effect on healthy ears]

OBJECTIVE

To investigate the mechanism of Central Masking Effects(CME) and its effects on audiometry measurement.

METHOD

The pure tone threshold was measured when the notest ear was masked or was in quiet respectively. We investigated the different results while giving different level maskers at the same frequency, or giving the same masker at different frequencies to find out their rules.

RESULT

The CME has frequency-selective properties and sound level-selective properties. The CME appears apparently at 1 kHz and 2 kHz. At 2 kHz, the CME get the highest. When the masker was lower than 60 dB HL, the CME became higher as the masker was tuned higher; when the masker was 60 dB HL, the CME get the highest[(11.53 +/- 4.38)dB HL]. If the masker was higher than 70 dB HL, overmasking appeared.

CONCLUSION

Our observations come to the conclusion that central masking correction should be made clinically when the masker is higher than 40 dB HL. 60 dB HL masker at 2 kHz can make the CME higher than 10 dB HL, thereby can be used to identify false deafness.

In vitro secretion kinetics of proteins from Legionella pneumophila in comparison to proteins from non-pneumophila species

It has been shown that the loss of PilD, a prepilin peptidase necessary for type IV pilus biogenesis and establishment of the type II secretion apparatus is associated with loss of virulence in Legionella pneumophila. L. pneumophila is the species most frequently associated with Legionnaires' disease, but virulence factors unique to this species are not known, so the secretion kinetics of several pilD-dependent enzyme activities, including protease, acid phosphatase, phospholipase A (PLA) and lysophospholipase A (LPLA), of L. pneumophila and non-pneumophila species were compared during growth in BYE broth. Enzyme activity appeared during mid-exponential growth phase and reached maximal levels on entry into stationary growth phase. None of the enzyme activities were unique to L. pneumophila and it did not exclusively secrete the highest amounts of the hydrolytic proteins. However, the timing of PLA and LPLA secretion in L. pneumophila differed compared to other species. PLA activity was secreted prior to LPLA activity in L. pneumophila, which may lead to an accumulation of the cytotoxic agent lysophosphatidylcholine (LPC). In addition to L. pneumophila, several other Legionella species, including Legionella steigerwaltii and Legionella gormanii, were able to enrich for LPC due to a very potent PLA activity accompanied by only moderate LPLA activity. These species, in contrast to L. pneumophila, have not been shown to multiply within monocytic host cells. Thus none of the secreted enzymic activities investigated were unique to L. pneumophila, nor were they secreted at high concentrations. However, the timing of PLA and LPLA secretion may contribute to pathogenicity.

Isolation and purification of guinea pig inner ear antigens by preparative polyacrylamide gel electrophoresis

OBJECTIVE

To isolate and purify the subcomponents of guinea pig inner ear antigens for further study on the autoimmunity of the inner ear.

METHODS

Inner ear tissues were homogenized in phosphate buffered saline containing 0.1% SDS, and then frozen and defrosted repeatedly to extract inner ear antigens. Preparative polyacrylamide gel electrophoresis was used to separate the subcomponents of inner ear antigens. Following electrophoresis, the protein bands were localized by rapid staining and destaining.

RESULTS

The major protein bands were clearly distinct when 3 mg of crude inner ear antigens was loaded, and the three major subcomponents (31, 42-45 and 60 kD proteins) accounted for about 25.99%, 21.91% and 21.10%, respectively.

CONCLUSION

Preparative polyacrylamide gel electrophoresis can be used to purify the major subcomponents of inner ear antigens.

[Relationship between three inner ear antigens and autoimmune inner ear disease]

OBJECTIVE

To investigate the relationship between three purified inner ear antigens and autoimmune inner ear disease (AIED), and to determine their expressions in normal guinea pig cochleas.

METHODS

Guinea pigs were divided into group B, group C and group D and immunized respectively with three subcomponents of crude inner ear antigens (31,000, 42,000-45,000 and 60,000 proteins). Hearing thresholds, serum IgG levels and morphological changes of inner ear were observed. The protein expressions of these antigens were examined by immunohistochemistry. In the control group, antigens were replaced by gel homogenate of polyacrylamide.

RESULTS

There were no significant differences of hearing threshold among groups before immunization with inner ear antigens (F = 0.07, P > 0.05). There were no significant changes of hearing thresholds and inner ear morphology in group C and control group. Hearing thresholds dropped in part of animals immunized with 31,000 or 60,000 protein. Hearing threshold of group B and D changed significantly after immunization, as compared with the control group(F = 9.12, P < 0.01). Serum IgG levels increased significantly in all experimental groups compared with the control group(F = 7.46, P < 0.01). The 31,000 protein distributed strictly in cochlear nerve, and 42,000-45,000 or 60,000 protein distributed widely, including the spiral ganglion, Corti's organ, stria vascularis and spiral ligament.

CONCLUSIONS

Two subcomponents of 31,000 and 60,000 in crude inner ear antigen could induce autoimmune inner ear disease. The distribution of 31,000 protein was more tissue specific and might be used as a marker protein for clinical diagnosis of autoimmune inner ear disease.

[A retrospective study on cholesteatoma otitis media coexisted with cholesterol granuloma]

OBJECTIVE

To investigate the etiology and pathogenesis of cholesteatoma otitis media accompanied by cholesterol granuloma and the relationship between cholesteatoma and cholesterol granuloma.

METHODS

Sixty three cases of middle ear cholesterol granuloma treated in our hospital during the period from March 1988 to May 2000 were retrospectively reviewed. All cases were verified by surgery and pathology. Fifteen cases of cholesteatoma coexisted with cholesterol granuloma were found among the 63 patients.

RESULTS

All fifteen cases had a long-term history of otitis media, such as otorrhea (sanguine purulent otorrhea and bloody otorrhea in 8 cases) and perforation of the ear drum (perforation of pars flaccida in 8 cases). Temporal bone CT scans showed cholesteatoma in 11 cases. All patients were treated surgically, and cholesteatoma and cholesterol granuloma were found coexisting alternatively, and the latter lied mainly in the tympanic antrum, attic and mastoid air cells. Chocolate-colored mucus was accumulated in well-developed mastoid air cells, and glistening dotty cholesterol crystals were also found. In most cases, enlarged aditus, destruction of lateral attic wall, erosion of ossicular chain, exposition of horizontal segment of facial nerve and tegmen of attic were found. Occlusion of Eustachian tube was found in 6 cases, and occlusion of tympanic isthmus was found in all cases. A post-operative dry ear was obtained, and hearing improved in all 12 cases following tympanoplasty.

CONCLUSIONS

Cholesteatoma and cholesteatoma granuloma in middle ear may share a common pathophysiological etiology, an occlusion of ventilation and a disturbance of drainage. The diagnosis should be considered when patients with chronic otitis media presented with bloody otorrhea. CT and magnetic resonance imaging(MRI) are useful for the diagnosis before operation. The surgical approach depends on the location, extension and severity of the lesion, and the principle of surgery is to clear the lesion and create an adequate drainage.

Characterization of the Yersinia pestis Yfu ABC inorganic iron transport system

In Yersinia pestis, the causative agent of plague, two inorganic iron transport systems have been partially characterized. The yersiniabactin (Ybt) system is a siderophore-dependent transport system required for full virulence. Yfe is an ABC transport system that accumulates both iron and manganese. We have identified and cloned a Y. pestis yfuABC operon. The YfuABC system is a member of the cluster of bacterial ABC iron transporters that include Sfu of Serratia, Hit of Haemophilus, and Yfu of Yersinia enterocolitica. The Y. pestis KIM6+ system is most homologous to that in Y. enterocolitica, showing identities of 84% for YfuA (periplasmic binding protein), 87% for YfuB (inner membrane permease), and 75% for YfuC (ATP hydrolase). We constructed a yfuABC promoter-lacZ fusion to examine regulation of transcription. This promoter contains a potential Fur binding sequence and is iron and Fur regulated. Significant expression from the yfuABC promoter occurred during iron-deficient growth conditions. In vitro transcription and translation of a recombinant plasmid encoding yfuABC indicates that YfuABC proteins are expressed. Escherichia coli 1017 (an enterobactin-deficient mutant) carrying this plasmid was able to grow in an iron-restrictive complex medium. We constructed a deletion encompassing the yfuABC promoter and most of yfuA. This mutation was introduced into strains with mutations in Ybt, Yfe, or both systems to examine the role of Yfu in iron acquisition in Y. pestis. Growth of the yfu mutants in a deferrated, defined medium (PMH2) at 26 and 37 degrees C failed to identify a growth or iron transport defect due to the yfu mutation. Fifty percent lethal dose studies in mice did not demonstrate a role for the Yfu system in mammalian virulence.

[A study on the relations of soluble interleukin-2 receptor and CD+25 cell with acute graft-versus-host disease]

OBJECTIVE

Acute graft-versus-host disease (aGVHD) is one of the major complications after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Prediction of human aGVHD may be of help in its diagnosis and therapy.

METHODS

22 patients undergoing HSCT were included in this study. After transplantation, serum concentrations of interleukin-6, interleukin-8, tumor necrosis factor-alpha, interferon-gamma and sIL-2R were measured periodically by using enzyme-linked immunosorbent assay. Immune reconstitution of CD(+)(3), CD(+)(4), CD(+)(8), CD(+)(25) and CD(+)(69) cells were analyzed with flow cytometry.

RESULTS

All the patients achieved engraftment. 6 patients developed grade I GVHD and 4 patients developed grade III-IV GVHD. Patients with aGVHD demonstrated significantly higher sIL-2R levels than those without. The peak levels of grade III-IV GVHD were (420.3 +/- 59.8) U/L,and the peak levels of grade I GVHD were (221.5 +/- 38.8) U/L. The increase of sIL-2R level in serum preceded the clinical signs of aGVHD. The maximum levels of sIL-2R correlated significantly with the severity of aGVHD. The increase of CD(+)(25) cells was in accordance with that of sIL-2R.

CONCLUSIONS

Analysis of serum cytokines and immune reconstitution after HSCT may provide predictive value for aGVHD.

Novel lysophospholipase A secreted by Legionella pneumophila

We show that Legionella pneumophila possesses lysophospholipase A activity, which releases fatty acids from lysophosphatidylcholine. The NH2-terminal sequence of the enzyme contained FGDSLS, corresponding to a catalytic domain in a recently described group of lipolytic enzymes. Culture supernatants of a L. pneumophila pilD mutant lost the ability to cleave lysophosphatidylcholine.

[Types of chemokines expressed by murine dendritic cell line]

OBJECTIVE

To analyze the types of chemokines expressed in murine medullary thymic dendritic cell line (MTDC).

METHODS

A MTDC line was established. RT-PCR was used to amplify the cDNA fragments of SDF-1, IP-10, KC, MCP-1, and lymphotactin expressed by MTDC. Nucleotide sequencing and dot blotting analysis were performed to confirm their existence.

RESULTS

Five cDNA fragments SDF-1, KC, IP-10, MCP-1, and lymphotactin, were amplified from MTDC. The existence of SDF-1, KC, and lymphotactin was confirmed by nucleotide wequencing, and that of IP-10, MCP-1, and lymphotactin was confirmed by dot blotting. The supernatant of MTDC exhibited chemoattractant activities to CD(4)(-) approximately CD(8)(-) thymocytes with a chemotactic index (CI) of 3.4.

CONCLUSION

There is a lot of chemokines in MTDC, including C-X-C subfamily (SDF-1, KC, and IP-10) CC subfamily (MCP-1), and C subfamily (lymphotactin). The suparnatant of MTDC has moderately chemotactic activities to CD(4)(-) approximately CD(8)(-) thymocytes, consistent with the biological function of SDF-1.

Progress in the research and demonstration of Everglades periphyton-based stormwater treatment areas

The South Florida Water Management District (District) is conducting research focused on potential advanced treatment technologies to support reduction of phosphorus (P) loads in surface water entering the remaining Everglades. Periphyton-based stormwater treatment areas (PSTA) are one of the advanced treatment technologies being researched by the District. This detailed research and demonstration project is being conducted in two phases. Basic research in field-based mesocosm experiments was conducted during the first phase within the District's Everglades Nutrient Removal Project (ENR). Studies were conducted in 24 portable PSTA mesocosms and three of the south ENR test cells. Phase 1 studies addressed the effects of system substrate (shellrock, organic peat, or sand), water depth, hydraulic loading rate, vegetation presence, depth:width ratio, and inhibition of algal growth on total phosphorus removal performance of the PSTA mesocosms. A second phase of research is currently under way, during which PSTA feasibility will be evaluated further in four field-scale constructed mesocosms totaling about 2 ha, and follow up studies within the ENR test cells and portable mesocosms will be conducted to further investigate the effects of other inorganic substrates, shallow water depth, and velocity on treatment performance. Phase 1 monitoring has determined that periphyton-dominated communities can be established in constructed wetlands within 5 months. The algal component of these periphyton plant communities is characteristic of natural Everglades periphyton. High macrophyte densities resulted from use of peat soils in PSTA mesocosms, while shellrock and sand soils promoted more desirable sparse macrophyte stands. P removal rates under the conditions of this research were relatively high considering the low influent total P concentrations tested (average 23 microg/L). PSTA mesocosms on shellrock soils were able to attain long-term average outflow total P concentrations as low as 11 microg/L. The maximum one-parameter TP first-order removal rate constant (k1) measured was 27 m/y. Minimum attainable outflow total P concentrations and mass removals appear to be the result of a balance between internal P loading from antecedent soils, uptake and burial processes in new sediments, and rainfall inputs. A different soil type (limerock) will be tested for effectiveness during Phase 2. Selected existing treatments will also be continued to look for trends over a second growing season.

[Melanoma antigen-3 expression in human hepatocellular carcinoma]

OBJECTIVE

To investigate the expression of melanoma antigen-3 (MAGE-3) mRNA in human hepatocellular carcinoma (HCC) and probe into the theoretical feasibility that MAGE-3 antigens can be developed as a new peptide vaccine for immunotherapy in HCC patients.

METHODS

The expression of MAGE-3 mRNA in HCC tissues and the adjacent non-HCC liver tissues was studied using RT-PCR in 45 HCC patients. The results were compared with those of 16 cirrhotic patients and 12 patients whose liver tissues were pathologically normal. MAGE-3 mRNA positive PCR products were DNA sequenced in 3 HCC patients. The sequenced fragments of MAGE-3 cDNA were used as template by which a [alpha(32)P] labeled probe was synthesized and employed for Southern blot analysis. HLA class I-A and -B typing of 43 HCC patients were assayed by ELISA.

RESULTS

Of the 45 HCC samples, 35 (78%) expressed MAGE-3 mRNA and six HCC adjacent tissues were also positive in MAGE-3 expression. Pathological examination showed cellular heteromorphism in these adjacent tissues. The non-HCC liver tissues from cirrhosis and normal liver samples were not MAGE-3 mRNA detectable. The DNA sequence confirmed that the target gene fragment in all of the 3 samples of PCR products was MAGE-3 cDNA. Southern blotting result confirmed that of RT-PCR assay. In HCC patients, the predominant types of HLA were A(2) (53.5%), A(11) (25.6%), A(24) (20.9%), A(33) (20.9%), B(13) (28.3%), and B(35) (23.2%). MAGE-3 mRNA expression in HCC showed no correlation with the level of serum AFP and the size of the tumor.

CONCLUSIONS

MAGE-3 mRNA is expressed at a high percentage of HCC samples. This tumor rejection antigen may be used as peptide vaccine for immunotherapy of HCC patients. The phenomena that some non-HCC adjacent tissues with heteromorphism can express MAGE-3 like their paired HCC tissues indicate that the expression of MAGE-3 may be an indicator in the early stage of carcinogenesis of liver tissues.

A monoclonal antibody to the DEC-205 endocytosis receptor on human dendritic cells

DEC-205 is a multilectin receptor for adsorptive endocytosis, expressed in mouse dendritic cells (DC) and some epithelia. DEC-205 is homologous to the macrophage mannose receptor (MMR). A cDNA for murine DEC-205 was used to identify 3 overlapping human DEC-205 clones from a lymphocyte library. The human homologue is a transmembrane protein of 1722 aminoacids with 10 externally disposed C-type lectin domains having 77% identity to the mouse counterpart. The NH(2) terminal cysteine-rich and fibronectin type II domains were expressed and used to immunize mice. A hybridoma, MG38, which specifically recognized the immunogen was obtained from a DEC-205 knockout mouse. The antibody precipitated a 205 kD protein from metabolically labeled, monocyte-derived DCs. MG38 labeled mature monocyte-derived DCs but showed weak or no labeling of other peripheral blood mononuclear cells. In tissue sections, MG38 identified DEC-205 on thymic cortical epithelium and DCs in the thymic medulla and tonsillar T cell areas. In contrast, an anti-MMR antibody stained DEC-205 negative, macrophages in the thymus cortex, the trabeculae of the thymus and tonsil, as well as efferent lymphatics in the tonsil. Therefore, the MG38 anti-DEC-205 antibody is useful for identifying DCs and reveals clear differences in sites where MMR and DEC-205 are expressed in lymphoid tissues.

New evidence for an extra-hepatic role of N-acetylglucosaminyltransferase III in the progression of diethylnitrosamine-induced liver tumors in mice

N-acetylglucosaminyltransferase III (GlcNAc-TIII) is encoded by the Mgat3 gene and catalyzes the addition of the bisecting GlcNAc to the core of N-glycans. Mice lacking GlcNAc-TIII due to the insertion mutation Mgat3tmlPst (termed Mgat3neo), exhibit retarded progression of liver tumors induced by diethylnitrosamine (DEN; M. Bhaumik et al, Cancer Res., 58: 2881-2887, 1998). This phenotype seemed to be due to a reduction, in activity or amount, of a circulating glycoprotein(s) that enhances DEN-induced liver tumor progression. Here, we provide new evidence to support this hypothesis. First, we show that mice with a deletion mutation of the Mgat3 gene coding exon (Mgat3tmlJxm, termed Mgat3delta) also exhibit retarded progression of DEN-induced liver tumors. At 7 months there was a significant decrease in liver weight (approximately 27%; P < 0.01), reflecting reduced tumor burden in Mgat3delta/delta mice. In addition, tumors were generally fewer and smaller, and histological changes were less severe in Mgat3delta/delta livers. Therefore, tumor progression is retarded in mice with two different null mutations in the Mgat3 gene. Second, we show that the development of DEN-induced tumors is unaltered by high levels of GlcNAc-TIII in the liver of transgenic mice. The Mgat3 gene coding exon under the control of the major urinary protein (MUP) promoter was used to generate transgenic mice that express GlcNAc-TIII in liver. Following DEN injection and phenobarbitol treatment, however, no significant differences were observed between MUP/Mgat3 transgenic and control mice in either tumor numbers or liver weight. The combined data provide strong evidence that retarded progression of tumors in mice lacking GlcNAc-TIII is due to the absence of the bisecting GlcNAc residue on N-glycans of a circulating glycoprotein(s) from a tissue other than liver.

DEC-205 as a marker of dendritic cells with regulatory effects on CD8 T cell responses

We have previously reported that a population of lymphoid-related CD8alpha(+) DEC-205(+) dendritic cells (DC) from mouse spleen have 'regulatory' effects on the T cells they activate. CD8 T cells produce IL-2 and give a sustained proliferative response to allogeneic CD8alpha(-) DEC-205(-) splenic DC, but produce little IL-2 and give a limited response to allogeneic CD8(+) DEC-205(+) splenic DC. Although CD8alpha and DEC-205 correlate closely among splenic DC, lymph nodes (LN) include a large population of CD8alpha(low) DEC-205(high) DC. By i.v. transfer of purified thymic early lymphoid precursors into irradiated recipient mice we now demonstrate that these CD8alpha(low) but DEC-205(high) LN DC can be the progeny of a lymphoid precursor population, apparently corresponding to the CD8alpha(high) DEC-205(high) DC progeny of the same precursors in spleen and thymus. By culture of the separated, purified DC with allogeneic CD8 T cells we demonstrate that the CD8alpha(low) DEC-205(high) DC of LN are also functionally equivalent to the CD8alpha(high) DEC-205(high) DC of spleen. Therefore, DEC-205 but not CD8alpha serves to segregate functionally distinct DC types in LN. However, DC isolated from the spleens of genetically manipulated DEC-205(null) mice and separated on the basis of CD8alpha expression have a similar capacity to stimulate CD8 T cells as their heterozygous littermate controls, with the CD8alpha(+) but now DEC-205(null) DC still giving restricted responses. In conclusion, high expression of DEC-205 appears to be a good marker of the lymphoid-related regulatory type of DC, but DEC-205 itself is not responsible for transmitting negative signals to the T cells.

[Expression of heat shock protein 70 in immune response of the guinea pig inner ear]

OBJECTIVE

To explore whether the immune response of the inner ear could induce heat shock protein (hsp) 70 in guinea pig cochlea.

METHODS

A model of autoimmune inner ear disease (AIED) was established by systemically immunizing the guinea pig with the homologous crude inner ear antigen (CIEAg). The immunized cochleae and normal control cochleae were examined for the expression of hsp70 with techniques of immunohistochemistry and in situ hybridization.

RESULTS

In the control animals, the expression of the hsp70-like protein appeared only in the spiral ganglion, whereas in the cochleae with CIEAg immunization, strong expression of the hsp70-like protein and its mRNA appeared in the spiral ganglion as well as in the stria vascularis and the spiral ligament. The hearing thresholds were significantly increased in 10 out of 28 cochleae (35.7%) with CIEAg immunization.

CONCLUSION

The results suggest that the immune response of the inner ear can induce the expression of hsp70 in the guinea pig cochlea.

Isoelectric focusing nonporous RP HPLC: a two-dimensional liquid-phase separation method for mapping of cellular proteins with identification using MALDI-TOF mass spectrometry

A novel two-dimensional liquid-phase separation method was developed that is capable of resolving large numbers of cellular proteins. The proteins are separated by pI using isoelectric focusing in the first dimension and by hydrophobicity using nonporous reversed-phase HPLC in the second dimension (IEF-NP RP HPLC). Proteins were mapped using original software in order to create a protein pattern analogous to that of the 2-D PAGE image. RP HPLC peaks are represented by bands of different intensity in the 2-D image, according to the intensity of the peaks eluting from the HPLC. Each peak was collected as the eluent of the HPLC separation in the liquid phase. The proteins collected were identified using proteolytic enzymes, MALDI-TOF MS and MSFit database searching. Using IEF-NP RP HPLC, approximately 700 bands were resolved in a pI range from 3.2 to 9.5 and 38 different proteins with molecular weights ranging from 12,000 to 75,000 were identified. In comparison to a 2-D gel separation of the same human erythroleukemia cell line lysate, the IEF-NP RP HPLC produced improved resolution of low mass and basic proteins. In addition, the proteins remained in the liquid phase throughout the separation, thus making the entire procedure highly amenable to automation and high throughput. It is demonstrated that IEF-NP RP HPLC provides a viable alternative to the 2-D gel separation method for the screening of protein profiles.

Novel phospholipase A activity secreted by Legionella species

Bacterial phospholipases are regarded as a major virulence factor in infection. In bacteria associated with pneumonia, destruction of lung surfactant and host cell membranes by bacterial phospholipases secreted during infection is thought to contribute to the disease. Phospholipase C (PLC) activity has been described in several Legionella species (W. B. Baine, J. Gen. Microbiol. 134:489-498, 1988; W. B. Baine, J. Gen. Microbiol. 131:1383-1391, 1985). By using detection methods such as thin-layer chromatography and mass spectrometry, PLC activity could not be detected in several strains of Legionella pneumophila. Instead, phospholipid degradation was identified to be caused by a novel PLA activity. We could demonstrate that PLA secretion starts at the mid-exponential-growth phase when bacteria were grown in liquid culture. Several Legionella species secreted different amounts of PLA. Legionella PLA may act as a powerful agent in the mediation of pathogenicity due to destruction of lung surfactant and epithelial cells.

[Parasitic metamorphosis development of Lamprotula fibrosa]

The glochidia of Lamprotula fibrosa develop to maturity in the outer gill of female and are expelled to the outside in winter, and then, the mature glochidia are parasitized to the gill of fish host and start the parasitic metamorphosis development. The parasitic period lasts about 4 months. The inner and outer byssuses disappear after parasitizing for 3 days. The foots develop after 35 days. The intestine, adductor muscle, nephridium and gill anlage develop after 90 days. The shells become thick and protrusive. The glochidia become larvae with a size of 253.37 x 273.26 x 179.96 microns in the next spring, then leave the gill of fish host, and start their independent life.

Discernment of the sensitized inner ear by peripheral immunocompetent lymphocytes

OBJECTIVE

To investigate the role of peripheral immunocompetent lymphocytes during the immune response in the inner ear.

METHODS

Sensitized lymphocytes from peripheral blood, neck lymph nodes and spleen of three groups of donor animals, i.e., group A immunized intradermally with keyhole limpet hemocyanine (KLH) and both inner ears challenged with KLH, group B received only KLH intradermally without inner ear challenge, and group C used as control, were isolated and labelled with 51Cr. The labelled lymphocytes were injected intravenously into the recipients. They were immunized intradermally with right inner ears challenged with KLH. Twenty to 24 h later, the radioactivities in the temporal bones of the recipients were assayed to detect the infiltration of labelled cells.

RESULTS

In groups A and B, the radioactivity in the right temporal bones was higher than that in the left temporal bones (P < 0.05). The highest labelling radioactivity was detected in the right temporal bones of group A. The lowest migration of 51Cr-labelled cells to the inner ear was found in group C. The ratio of radioactivity between right (challenged) and left (unchallenged) inner ears was higher in group A than in groups B and C, with the difference being significant (P < 0.05).

CONCLUSION

The immune reaction in response to antigenic stimulation in the inner ear is immunologically modulated by the peripheral systemic circulation.

[Nerve electrogram study on different degrees injuries of recurrent laryngeal nerve]

OBJECTIVE

To study the display of different degrees injuries of recurrent laryngeal nerve in electroneurogram.

METHOD

We imitated several common types of injuries i.e. stretch, claming, electrocautery and cut in cervial segment of recurrent laryngeal nerve and measured latency and amplitude of the nerve by electroneurography.

RESULT

The normal value of latency was (1.58 +/- 0.14) ms and that of amplitude was (2.53 +/- 0.78) mV; stretch group was (2.43 +/- 0.32) ms and (0.95 +/- 0.23) mV; claming group was (2.99 +/- 0.55) ms and (0.62 +/- 0.22) mV; electrocautery group was (4.85 +/- 1.03) ms and (0.24 +/- 0.15) mV; cut group was infinity ms and 0 mV.

CONCLUSION

Latency correlated directly with the degree of nerve injury. Whereas amplitude correlated inversely with the degree of nerve injury. Stretch injured recurrent laryngeal nerve the least, followed by claming, electrocautery and cut. This method could be used for nerve monitoring during operation and prognostic judgement.

[Rescue and prevention of serious systemic toxicity following local anesthesia to mucous membranes of tetracaine]

Tetracaine remains a popular agent in clinical for the purpose of local anesthesia to mucous membranes. Its potential for systemic absorption and resulting toxicity has been seldom emphasized. One case of fatality from tetracaine pharyngeal local anesthesia for fibro-laryngoscopic procedure is described. The pharmacologic basis, clinical features, rescue and prevention for systemic toxicity is discussed.

[Determination of IL-6 in serum and perilymph during inner ear immune response]

During secondary inner ear immune responses against keyhole limpet hemocyanin (KLH), to understand the change of interleukin-6 (IL-6) levels in perilymph and serum, IL-6 levels in perilymph and serum were investigated using an immunoassay. No IL-6 levels were detectable at Day 0 in perilymph. The earliest perilymph IL-6 levels were observed after 6 h, peaking at 24 h, and then decreasing gradually. IL-6 level remnants were detected at 7 days in perilymph. In contrast, during this observation period, low IL-6 levels were only detectable in perilymph from control ears, disappearing after 72 h. IL-6 levels don't change in serum. Previous study has identified the endolymphatic sac (ES) lags behind the earlier appearance of intercellular adhesion molecule-1 (ICAM-1) in the spiral modiolar vein and spiral ligament during immune response. The present study not only provides further support for the existence of an inner ear immune response which is regulated by cytokines, but also supports that cytokines controlling expression of adhesion molecules are released probably by cells which located out of ES.

[Pharmcognostial study on the Geranium wilfordii var. glandulosum]

First time has done pharmcognostical research on the Geranium wilfordii Maxim var. glandulosum Z. M. Tan, including microscopic identification, chemical qualitative test and bacteriostatic test.