Genetic characterization and authentication of Dimocarpus longan Lour. using an improved RAPD technique

Dimocarpus longan Lour. is an edible and traditional herb in China, commonly referred to as longon. An improved randomly amplified polymorphic DNA (RAPD) protocol was here developed in order to determine the geographical origins of D. longan samples collected from 5 provinces in the southern and southwestern areas of China, including Sichuan, Hainan, Fujian, Guangdong, and Guangxi. Generally, the improved RAPD method generated good fingerprinting of the 5 samples using the selected 17 primers. In particular, primers SBS-A5, SBS-A13, SBS-I9, SBS-I20, SBS-M1, and SBS-Q12 produced distinguishable bands that clearly separated all 5 cultivars, suggesting that there are variations in RAPD genetic sites among the samples. The similarity index ranged from 0.69 to 0.76. The Sichuan and Hainan clades clustered together with a 0.73 similarity index. The Guangxi and Fujian clades clustered together with a 0.76 similarity index, and they formed the sister clade to the Sichuan/Hainan clade with a 0.71 similarity index. The Guangdong clade was in a basal polytomy with a 0.70 similarity index. Based on the abundant DNA polymorphisms, these longan accessions are distinguishable using our improved RAPD technique. Therefore, RAPD analysis is an effective technique in distinguishing the geographical origins of D. longan. Moreover, the improved method could also be employed for a variety of applications including genetic diversity and fingerprinting analyses.

Bosentan reduces neuronal apoptosis following spinal cord ischemic reperfusion injury

STUDY DESIGN

Experimental study.

OBJECTIVES

To investigate the effects of endothelin-receptor antagonist Bosentan on the spinal neural apoptosis in rats with ischemic reperfusion (IR) injury.

SETTING

Department of Neurosurgery, the Second Affiliated Hospital, Xi'an Jiaotong University School of Medcine, Xi'an, Shaanxi Province, China:

METHODS

Sprague-Dawley Rats were randomly divided into two groups, saline (IRS, n=48) and Bosentan (IRB, n=48) treatment, respectively, when reperfused in 6 h, 12 h, 24 h, 3 days, 5 days and 7 days. Immunohistochemical staining was used to assess endothelin-1 (ET-1), endothelin receptor type A (ETRA), endothelin receptor type B (ETRB), Bcl-2, Bax, Caspase-8, Caspase-9 and Caspase-3 expression. ET-1 and its receptor in spinal cord tissue were evaluated by real-time PCR. Plasma ET-1 concentration was also detected using radioimmunoassay.

RESULTS

Compared with the group IRS, plasma concentration of ET-1 in group IRB was significantly increased at each time point (P<0.05) and peaked at 24 h (P<0.01). ETRB expression in group IRB was significantly higher than group IRS at each time point (P<0.05) and peaked at day 3 (P<0.01). The difference in the expression of ETRA was not statistically significant in the group IRS and IRB (P>0.05). The apoptosis rate in group IRB was significantly decreased at each time point (P<0.05). The protein expressions of Bcl-2, Bax, Caspase-8, Caspase-9 and Caspase-3 were significantly increased in response to Bosentan treatment after IR.

CONCLUSION

These results suggest Bosentan decreases apoptosis rate after IR injury in the spinal cord, possibly through the ET-1-ETRB signaling pathway.

Virally expressed connexin26 restores gap junction function in the cochlea of conditional Gjb2 knockout mice

Mutations in GJB2, which codes for the gap junction protein connexin26, are the most common causes of human nonsyndromic hereditary deafness. We inoculated modified adeno-associated viral vectors into the scala media of early postnatal conditional Gjb2 knockout mice to drive exogenous connexin26 expression. We found extensive virally-expressed connexin26 in cells lining the scala media, and intercellular gap junction network was re-established in the organ of Corti of mutant mouse cochlea. Widespread ectopic connexin26 expression neither formed ectopic gap junctions nor affected normal hearing thresholds in wild type mice, suggesting that autonomous cellular mechanisms regulate proper membrane trafficking of exogenously-expressed connexin26 and govern the functional manifestation of them. Functional recovery of gap-junction-mediated coupling among the supporting cells was observed. We found that both cell death in the organ of Corti and degeneration of spiral ganglion neurons in the cochlea of mutant mice were substantially reduced, although auditory brainstem responses did not show significant hearing improvement. This is the first report demonstrating that virally-mediated gene therapy restored extensive gap junction intercellular network among cochlear non-sensory cells in vivo. Such a treatment performed at early postnatal stages resulted in a partial rescue of disease phenotypes in the cochlea of the mutant mice.

Microcellular Injection Molding

This paper reviews some of the recent developments of microcellular injection molding, which is capable of producing parts with excellent dimensional stability using lower injection pressure, shorter cycle time, and less material. Process conditions as well as nano/micro-fillers such as nanoclay and core–shell rubber have a strong influence on cell density and cell size, hence, the final material properties of the molded parts. The addition of nano/micro-fillers at optimum loading levels can generally facilitate the formation of microcellular plastics with higher cell density and smaller cell size leading to superior mechanical properties. The novel integration of a solid plastic surface with a microcellular plastic core via the co-injection molding technique has been investigated to achieve Class “A” surfaces and improved material performance. An improved mathematical model has been developed to simulate the cell growth behavior in the microcellular injection molding process.

Solid and Microcellular Polylactide-Carbon Nanotube Nanocomposites

In this study, polylactide (PLA)-multi-walled carbon nanotube (MWCNT) nanocomposites were melt-compounded using a twin-screw extruder. Solid and microcellular tensile bar specimens were produced via conventional and microcellular injection molding, respectively. Various characterization techniques were applied to study the static and dynamic mechanical properties, degree of MWCNT dispersion, cell morphology, and crystallization behavior. The addition of a small amount of MWCNTs led to a decrease in the cell size and an increase in the cell density of the microcellular PLA specimens. A transmission electron microscopy analysis of the PLA-MWCNT specimens revealed a higher degree of MWCNT dispersion in the microcellular PLA-MWCNT composite compared with its solid counterpart, indicating that the microcellular injection molding process further dispersed the MWCNTs. For both solid and microcellular specimens, the addition of 1.5 wt% MWCNTs reduced the specific strength, specific toughness and strain-at-break while exerting less impact on the specific modulus. The storage modulus was not affected significantly with the addition of MWCNTs, but was found to be higher for the microcellular specimens compared with their solid counterparts. Finally, the crystallinity of PLA increased with the addition of MWCNTs.

Injection Molded Solid and Microcellular Polylactide Compounded with Recycled Paper Shopping Bag Fibers

Recycled paper shopping bag fibers were melt-compounded using a batch mixer with biobased/biodegradable polylactide (PLA) at 10 and 30 wt.% using silane as a coupling agent. These PLA/fiber composites were then injection molded to produce both solid and microcellular tensile bars. The mechanical properties (specific modulus, specific tensile strength, specific toughness, and strain at break) of the neat PLA and PLA composites were tested and the cell morphology of the microcellular samples was examined using scanning electron microscopy. It was observed that the addition of the recycled paper shopping bag fibers resulted in an increase in cell density and decrease in average cell size for the microcellular components when compared with the neat PLA. The addition of the fibers increased the specific modulus of both solid and microcellular components, and high fiber contents (30 wt.%) resulted in an increase in specific tensile strength, yet yielded a decrease in the strain at break and specific toughness. The storage modulus was also improved with the addition of 10 and 30 wt.% fibers for both solid and microcellular components.

Arsenic trioxide alleviates airway hyperresponsiveness and promotes apoptosis of CD4+ T lymphocytes: evidence for involvement of the ER stress-CHOP pathway

BACKGROUND

Asthma is a chronic inflammatory disorder of the airway. Arsenic trioxide (ATO) is an ancient Chinese medicine, which is used to treat psoriasis, asthma, and acute promyelocytic leukemia.

AIM

We wanted to research the effect of arsenic trioxide on asthma.

METHODS

Using a murine model of asthma, the airway hyperresponsiveness was conducted by the Buxco pulmonary function apparatus. Total cell counts of BALF were counted with a counting chamber. Histopathological analysis of lung tissues was conducted by hematoxylin-eosin or periodic acid-schiff stain. CD4+T cells were purified from the spleen by positive selection, using immunomagnetic beads. Apoptosis measurements were done with Annexin-V/PI staining. Western blot analysis and real time-PCR were performed to assess the expression of C/EBP-homologous protein (CHOP) and glucose-regulated protein 78 (GRP78), respectively. RNA interference was conducted to inhibit the expression of CHOP.

RESULTS

We found that arsenic trioxide treatment alleviated airway hyperresponsiveness and reduced inflammation of the lung in asthmatic mice. Furthermore, arsenic trioxide treatment promoted apoptosis of CD4+T cells in vivo and in vitro. When CD4+T cells were cultured with arsenic trioxide for 5 h at a concentration of 5 μM, the expression of GRP78 and CHOP was increased. Treatment of CD4+T cells with CHOP siRNA, provided partial resistance to arsenic trioxide-induced apoptosis of CD4+T cells

CONCLUSIONS

These data demonstrated that arsenic trioxide can reduce the severity of asthma attacks and induce the apoptosis of CD4+ T cell which the ER stress-CHOP pathway involved.

Neural expression of the transcription factor THAP1 during development in rat

Loss of function mutations in THAP1 has been associated with primary generalized and focal dystonia in children and adults. THAP1 encodes a transcription factor (THAP1) that harbors an atypical zinc finger domain and plays a critical role in G(1)-S cell cycle control. Current thinking suggests that dystonia may be a neurodevelopmental circuit disorder. Hence, THAP1 may participate in the development of the nervous system. Herein, we report the neurodevelopmental expression patterns of Thap1 transcript and THAP1 protein from the early postnatal period through adulthood in the rat brain, spinal cord and dorsal root ganglia (DRG). We detected Thap1 transcript and THAP1-immunoreactivity (IR) in the cerebral cortex, cerebellum, striatum, substantia nigra, thalamus, spinal cord and DRG. Thap1 transcript expression was higher in the brain than in spinal cord and DRG at P1 and P7 and declined to similar levels at P14 and later time points in all regions except the cerebellum, where it remained high through adulthood. In the brain, THAP1 expression was highest in early development, particularly in the cerebellum at P7. In addition to Purkinje cells in the cerebellum, THAP1-IR was also localized to pyramidal neurons in the cerebral cortex, relay neurons in the thalamus, medium spiny and cholinergic neurons in the striatum, dopaminergic neurons in the substantia nigra, and pyramidal and interneurons in the hippocampus. In the cerebellar cortex, THAP1-IR was prominently distributed in the perikarya and proximal dendrites of Purkinje cells at early time-points. In contrast, it was more diffusely distributed throughout the dendritic arbor of adult Purkinje cells producing a moderate diffuse staining pattern in the molecular layer. At all time points, nuclear IR was weaker than cytoplasmic IR. The prominent cytoplasmic and developmentally regulated expression of THAP1 suggests that THAP1 may function as part of a cell surface-nucleus signaling cascade involved in terminal neural differentiation.

Regulation of μ-opioid type 1 receptors by microRNA134 in dorsal root ganglion neurons following peripheral inflammation

BACKGROUND

MOR1 is the main transcript of μ-opioid receptor (MOR) gene, which represents a mandatory molecule for the analgesic effects of opioids and plays an important role in the pathology of inflammatory pain. MicroRNAs (miR) are non-coding molecules that primarily modulate gene expression at the post-transcriptional level in various pathophysiological conditions. Based on in silico analysis, an exact match to the seed sequence of miR-134 was found in 3'-untranslated region of MOR1. Given the important roles of MOR1 in pain modulation, the purpose of this study is to investigate whether miR-134 can regulate the MOR1 following allodynia.

METHODS

Using Freund's adjuvant (CFA)-induced chronic inflammatory pain model, we investigated the expression profiles of miR-134 and MOR1 in rat dorsal root ganglia (DRG) using quantitative real-time polymerase chain reaction, in situ hybridization and immunohistochemistry, respectively. The relationship of miR-134 and MOR1 expressions was analysed by linear regression. Luciferase assay was used to examine whether MOR1 was the target of miR-134.

RESULTS

Our results showed that miR-134 expression level was inversely related to MOR1 expression. Down-regulation of miR-134 and up-regulation of MOR1 in the same tissues after inflammatory pain were observed. Functional experiments showed that MOR1 expression in SH-SY5Y cells was up-regulated after inhibition of miR-134, indicating that MOR1 was a target of miR-134.

CONCLUSIONS

Our present data suggested a model that miR-134 participated in CFA-induced inflammatory pain by balancing the expression of MOR1 in DRGs, which implied that miR-134 may be a potential therapeutic target for the treatment of neuropathic pain including inflammation.

Gene expression in accumbens GABA neurons from inbred rats with different drug-taking behavior

Inbred Lewis and Fisher 344 rat strains differ greatly in drug self-administration; Lewis rats operantly self-administer drugs of abuse including nicotine, whereas Fisher self-administer poorly. As shown herein, operant food self-administration is similar. On the basis of their pivotal role in drug reward, we hypothesized that differences in basal gene expression in GABAergic neurons projecting from nucleus accumbens (NAcc) to ventral pallidum (VP) play a role in vulnerability to drug-taking behavior. The transcriptomes of NAcc shell-VP GABAergic neurons from these two strains were analyzed in adolescents, using a multidisciplinary approach that combined stereotaxic ionotophoretic brain microinjections, laser-capture microdissection (LCM) and microarray measurement of transcripts. Laser-capture microdissection enriched the gene transcripts detected in gamma-aminobutyric acid (GABA) neurons compared to the residual NAcc tissue: a ratio of neuron/residual >1 and false discovery rate (FDR) <5% yielded 6623 transcripts, whereas a ratio of >3 yielded 3514. Strain-dependent differences in gene expression within GABA neurons were identified; 322 vs. 60 transcripts showed 1.5-fold vs. 2-fold differences in expression (FDR < 5%). Classification by gene ontology showed that these 322 transcripts were widely distributed, without categorical enrichment. This is most consistent with a global change in GABA neuron function. Literature mining by Chilibot found 38 genes related to synaptic plasticity, signaling and gene transcription, all of which determine drug abuse; 33 genes have no known association with addiction or nicotine. In Lewis rats, upregulation of Mint-1, Cask, CamkII , Ncam1, Vsnl1, Hpcal1 and Car8 indicates that these transcripts likely contribute to altered signaling and synaptic function in NAcc GABA projection neurons to VP.

Novel THAP1 sequence variants in primary dystonia

BACKGROUND

THAP1 encodes a transcription factor (THAP1) that harbors an atypical zinc finger domain and regulates cell proliferation. An exon 2 insertion/deletion frameshift mutation in THAP1 is responsible for DYT6 dystonia in Amish-Mennonites. Subsequent screening efforts in familial, mainly early-onset, primary dystonia identified additional THAP1 sequence variants in non-Amish subjects.

OBJECTIVE

To examine a large cohort of subjects with mainly adult-onset primary dystonia for sequence variants in THAP1.

METHODS

With high-resolution melting, all 3 THAP1 exons were screened for sequence variants in 1,114 subjects with mainly adult-onset primary dystonia, 96 with unclassified dystonia, and 600 controls (400 neurologically normal and 200 with Parkinson disease). In addition, all 3 THAP1 exons were sequenced in 200 subjects with dystonia and 200 neurologically normal controls.

RESULTS

Nine unique melting curves were found in 19 subjects from 16 families with primary dystonia and 1 control. Age at dystonia onset ranged from 8 to 69 years (mean 48 years). Sequencing identified 6 novel missense mutations in conserved regions of THAP1 (G9C [cervical, masticatory, arm], D17G [cervical], F132S [laryngeal], I149T [cervical and generalized], A166T [laryngeal], and Q187K [cervical]). One subject with blepharospasm and another with laryngeal dystonia harbored a c.-42C>T variant. A c.57C>T silent variant was found in 1 subject with segmental craniocervical dystonia. An intron 1 variant (c.71+9C>A) was present in 7 subjects with dystonia (7/1,210) but only 1 control (1/600).

CONCLUSIONS

A heterogeneous collection of THAP1 sequence variants is associated with varied anatomical distributions and onset ages of both familial and sporadic primary dystonia.

Investigation of stimulated Brillouin scattering media perfluoro-compound and perfluoropolyether with a low absorption coefficient and high power-load ability

The correlations between stimulated Brillouin scattering (SBS) characteristics of perfluoro-compound (PFC) and perfluoropolyether (PFPE) and their chemical structure are analyzed in detail and a series of new PFC and PFPE are reported. In the Nd:YAG laser system, the absorption coefficient, optical breakdown threshold (OBT), SBS threshold, and Brillouin frequency shift of new media such as FC-87, FC-43, HT-55, and DET are measured. Parameters such as gain coefficient, Brillouin linewidth, and phonon lifetime are calculated. The results demonstrate their good SBS properties: the absorption coefficients are below 10(-3)cm(-1) and OBTs are above 100 GW/cm(2). These media also exhibit a series of unique physicochemical properties, i.e., high heat-resistance, high oxidation stability, good chemical inertness, and insulation properties. The discovery of new media not only diversifies SBS medium, but also improves the performance of the SBS system, thereby laying a good foundation for the application of a SBS phase conjugation mirror in a high-power laser system.

New ORP/pH based control strategy for chlorination and dechlorination of wastewater: pilot scale application

Due to its efficiency and low capital demands, chlorination has been widely used for disinfection in many wastewater treatment plants. Since the oxidation power of free chlorine is bigger than combined chlorines which are formed from the reaction between chlorine and reducing agents in water (especially, NH4+ and organic nitrogen), for effective disinfection, excess amount of chlorine is added until all the reducing agents are oxidized and free chlorine is available. After chlorination, chlorine residues in wastewater are usually reduced with SO2 or sulfites before the treated wastewater is discharged, since they are toxic to aquatic life. Addition of excess amount of SO2 or sulfite should be avoided. Otherwise, they consume dissolved oxygen in a river or stream and may have adverse impact on the aquatic life. Determination of wastewater chlorine demand and of sulfite dosages for dechlorination has been a challenge to WWTP operators, due to the dynamic characteristics of wastewater. Recently, a new ORP/pH based approach to determine chlorine demand and sulfite dosage was proposed. The method utilizes significant points occurring on the pH and ORP profiles during chlorination and dechlorination titrations. In this study, the proposed automatic titration system has been implemented into a control system to optimize chlorine and sulfite doses for a pilot scale chlorination/dechlorination system. In short, the disinfection system with the pH/ORP based controller showed very successful results; complete inactivation of total coliforms, and almost zero residual chlorines and high DO in its effluent.

New process control strategy for wastewater chlorination and dechlorination using ORP/pH

Due to its efficiency and relatively low capital demanding, many wastewater treatment plants have applied chlorination for disinfection of treated wastewater before discharging it. However, determination of optimal doses of chlorine for chlorination and sulfite for dechlorination, which removes residual chlorine, should made to guarantee complete destruction of microorganisms in treated wastewater and to protect aquatic life in a receiving stream. In this study, a new ORP/pH based approach to determine endpoints of breakpoint chlorination and of dechlorinating titration and to optimize doses of chlorine and sulfite. In this new method, significant points on the ORP and pH profiles occurring during the titrations for chlorination and dechlorination were utilized to determine chlorine demand and sulfite dosage.

[The clinical investigation of bacteriology of chronic suppurative otitis media]

OBJECTIVE

To understand bacteriology of chronic suppurative otitis media (CSOM) and drug sensitivity of isolated bacteria for better treatment of CSOM.

METHOD

Secretions of 92 samples with chronic suppurative otitis media were collected and cultured for aerobic and anaerobic bacteria respectively. Drug sensitivity test of isolated bacteria was done.

RESULT

Aerobic bacteria was found in 75 of 92 samples (81.5%), the main pathogens were pseudomonas aeruginosa, aureus staphylococcus and bacillus proteus, and their sensitive rates for ciprofloxacin were 89.0%, 88.2% and 85.0% respectively. Anaerobic bacteria was found in 10 samples (10.9%) and the relative sensitive drug was cefoperazone sodium.

CONCLUSION

Pseudomonas aeruginosa, aureus staphylococcus and bacillus proteus are the main pathogens of chronic suppurative otitis media, and their sensitive rates for ciprofloxacin are high.

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.