Successful treatment of a paraneoplastic pemphigus in a teenager using plasmapheresis, corticosteroids and tumour resection

Paraneoplastic pemphigus (PNP) is a severe autoimmune blistering disease. Bronchiolitis obliterans (BO) is a common complication of PNP, is the major cause of death. PNP is rarely seen before the age of 18 years, and the prognosis is poor because of BO. We report a 16-year-old girl with the typical findings of PNP associated with Castleman's tumour. She was treated with tumour resection in combination with plasmapheresis and corticosteroids. Fifteen months after the operation, the patient had recovered without the development of BO.

Glutamine induces heat shock protein 70 expression via O-GlcNAc modification and subsequent increased expression and transcriptional activity of heat shock factor-1

BACKGROUND

Glutamine (Gln) has been shown to induce heat shock protein (HSP) expression and to attenuate lipopolysaccharide (LPS)-mediated cardiovascular dysfunction, but the underlying mechanisms are not fully clear. We tested the hypothesis that protection by Gln-induced HSP70 expression is due to enhanced O-linked β-N-acetylglucosamine (O-GlcNAc) modification levels and subsequent increases in the levels of endonuclear heat shock protein factor-1 (HSF-1) expression and HSF-1 transcriptional activity in LPS-treated cardiomyocytes.

METHODS

Primary cultures of neonatal rat cardiomyocytes were divided into control, LPS (4 μg/mL), Gln+LPS (Gln 5 mM+LPS 4 μg/mL), Gln+LPS+Alloxan (an O-linked-N-acetyl glucosamine transferase inhibitor, 1 mM) and Gln+LPS+PUGNAc (an O-GlcNAcase inhibitor; 100 μM) groups. After incubation for six hours, the levels of cardiomyocyte viability, lactate dehydrogenase (LDH) activity, O-GlcNAc modification, endonuclear HSF-1 expression, HSF-1 transcription activity and cellular HSP70 expression were measured in all groups.

RESULTS

There were no significant differences in cell viability among the five groups. LDH activity levels were much higher in the LPS group than in the control group, but they markedly decreased in the Gln+LPS group (P<0.05). Gln's protection in the Gln+LPS group was associated with a significant increase in the levels of O-GlcNAc modification, endonuclear HSF-1 expression, HSF-1 transcription activity and cellular HSP70 expression compared to the LPS group (P<0.05). The protective action by Gln in LPS-treated cardiomyocytes could either be mimicked by 1 μM PUGNAc or banished by 1 mM alloxan.

CONCLUSION

Gln induces HSP70 expression and attenuates LPS-induced cardiomyocyte damage. The molecular mechanism of Gln-induced HSP70 expression appears to be mediated via enhancement of O-GlcNAc modification and subsequently to increase levels of endonuclear HSF-1 expression and HSF-1 transcription activity.

A novel porcine gene--SLC9A3R2, differentially expressed in the longissimus muscle tissues from Meishan and Large White pigs

The mRNA differential display technique was performed to investigate the differences of gene expression in the longissimus muscle tissues from Meishan and Large White pigs. One novel gene that was differentially expressed was identified through semi-quantitative RT-PCR and the cDNA complete sequence was then obtained using the rapid amplification of cDNA ends (RACE) method. The nucleotide sequence of the gene is not homologous to any of the known porcine genes. The sequence prediction analysis revealed that the open reading frame of this gene encodes a protein of 337 amino acids that has high homology with the solute carrier family 9 isoform 3 regulator 2 isoform a of four species--human (92 %), mouse (91 %), rat (90 %), rabbit (87 %)--so that this gene can be defined as swine SLC9A3R2 gene. The phylogenetic tree analysis revealed that the swine SLC9A3R2 gene has the closest genetic relationship with the SLC9A3R2 gene of human. This gene is structured in seven exons and six introns as revealed by computer-assisted analysis. The tissue expression analysis indicated that the swine SLC9A3R2 gene is differentially expressed in different tissues. Our experiment is the first to establish the primary foundation for further research on the swine SLC9A3R2 gene.

Prior knowledge based mining functional modules from Yeast PPI networks with gene ontology

BACKGROUND

In the literature, there are fruitful algorithmic approaches for identification functional modules in protein-protein interactions (PPI) networks. Because of accumulation of large-scale interaction data on multiple organisms and non-recording interaction data in the existing PPI database, it is still emergent to design novel computational techniques that can be able to correctly and scalably analyze interaction data sets. Indeed there are a number of large scale biological data sets providing indirect evidence for protein-protein interaction relationships.

RESULTS

The main aim of this paper is to present a prior knowledge based mining strategy to identify functional modules from PPI networks with the aid of Gene Ontology. Higher similarity value in Gene Ontology means that two gene products are more functionally related to each other, so it is better to group such gene products into one functional module. We study (i) to encode the functional pairs into the existing PPI networks; and (ii) to use these functional pairs as pairwise constraints to supervise the existing functional module identification algorithms. Topology-based modularity metric and complex annotation in MIPs will be used to evaluate the identified functional modules by these two approaches.

CONCLUSIONS

The experimental results on Yeast PPI networks and GO have shown that the prior knowledge based learning methods perform better than the existing algorithms.

Construction of gene networks with hybrid approach from expression profile and gene ontology

Gene regulatory networks have been long studied in model organisms as a means of identifying functional relationships among genes or their corresponding products. Despite many existing methods for genome-wide construction of such networks, solutions to the gene regulatory networks problem are however not trivial. Here, we present, a hybrid approach with gene expression profiles and gene ontology (HAEO). HAEO makes use of multimethods (overlapping clustering and reverse engineering methods) to effectively and efficiently construct gene regulatory networks from multisources (gene expression profiles and gene ontology). Application to yeast cell cycle dataset demonstrates HAEO's ability to construct validated gene regulatory networks, such as some potential gene regulatory pairs, which cannot be discovered by general inferring methods and identifying cycles (i.e., feedback loops) between genes. We also experimentally study the efficiency of building networks and show that the proposed method, HAEO is much faster than Bayesian networks method.

A semi-supervised approach to projected clustering with applications to microarray data

Recent studies have suggested that extremely low dimensional projected clusters exist in real datasets. Here, we propose a new algorithm for identifying them. It combines object clustering and dimension selection, and allows the input of domain knowledge in guiding the clustering process. Theoretical and experimental results show that even a small amount of input knowledge could already help detect clusters with only 1% of the relevant dimensions. We also show that this semi-supervised algorithm can perform knowledge-guided selective clustering when there are multiple meaningful object groupings. The algorithm is also shown effective in analysing a microarray dataset.

Genetic imbalance related to cisplatin-based chemoresistance in epithelial ovarian cancer

PURPOSE OF INVESTIGATION

To identify genetic imbalance related to chemoresistance in epithelial ovarian cancer.

METHODS

We screened abnormal chromosomal regions in cisplatin-resistant and cisplatin-sensitive human ovarian cancer cell lines employing comparative genomic hybridization (CGH). We also documented non-random chromosome gains and losses with cisplatin-resistant and cisplatin-sensitive primary epithelial ovarian tumors from patients.

RESULTS

There were extensive chromosome changes in cisplatin-resistant and cisplatin-sensitive cell lines. Gains of 1q12-22, 17q21-22 and loss of 3p21-24 were significantly more common in drug-resistant tumors from patients compared to the drug-sensitive group.

CONCLUSIONS

The special chromosomal aberrances might provide us with a clue for further investigation of the dominant mechanism that leads to a drug-resistant phenotype.

Antigenic differentiation of strains of turkey rhinotracheitis virus using monoclonal antibodies

Monoclonal antibodies (mAbs) were prepared against one UK isolate of turkey rhinotracheitis virus (TRTV). Those which were virus-neutralizing were selected and used, together with polyclonal antisera raised to each isolate in turkeys, in cross-neutralization tests against TRTV strains isolated in the UK and elsewhere. Whilst the polyclonal antisera showed that there was some diversity between them, all strains examined belonged to one serotype. The TRTV strains isolated in the UK could clearly be differentiated from those isolated elsewhere by some of the mAbs. Isolates of TRTV made in South Africa in 1978 and UK in 1985 were more closely related than were isolates made in UK and France within a few months. TRTV strains isolated from turkeys and chickens could not be differentiated. Some mAbs were found to be group-specific in that they neutralized all TRTV strains examined. All mAbs were of either the IgGl or IgG2a isotype and recognized the surface G glycoprotein.

Evaluation on the effects of relaxing music on the recovery from aerobic exercise-induced fatigue

AIM

There are few researches on the effects of music therapy on the recovery from exercise-induced fatigue worldwide. The aim of this study was to evaluate the effects of relaxing music on aerobic exercise-induced fatigue. The authors' hypothesis is that relaxing music can effectively eliminate aerobic exercise-induced fatigue.

METHODS

Thirty healthy male college students were randomly assigned to either no-music group or music group. All the subjects maintained the pedal cadence of 50 rev.min-1 on a cycle ergometer until fatigue. Then subjects in music group listened to relaxing music for 15 minutes, while subjects in no-music group had a 15-minute rest without music. Heart rates, jump height, blood glucose, blood lactic acid, urinary protein, simple reaction time and ratings of perceived exertion (RPE) were determined before and after the 15-minute treatment for each group.

RESULTS

The results showed that heart rates, urinary protein and RPE decreased significantly after the application of relaxing music (P<0.01), and these decreases were greater than those without music.

CONCLUSION

The results suggest that relaxing music has better effects on the rehabilitation of cardiovascular, central, musculoskeletal and psychological fatigue and the promotion of the regulatory capability of the kidneys.

The successive development of acute myeloblastic leukemia, secondary non-Hodgkin's lymphoma and secondary myeloid/natural killer cell acute leukemia in a single patient

We report a very rare case of a female patient who was initially diagnosed with acute myeloid leukemia (AML) M2 who achieved complete remission (CR) after chemotherapy. Six years later she was still in continuous complete remission from leukemia, but developed a right nasal obstruction and based on the nasal and nasopharynx biopsies, a secondary B cell non-Hodgkin's lymphoma was diagnosed and treated with chemotherapy and involved field radiotherapy. One year and seven months after the completion of therapy she presented with fever, dyspnea and leukocytosis. The blasts were now negative for myeloperoxidase and immunophenotyping showed that they were positive for CD13 and CD56. Now the diagnosis of a secondary myeloid/NK cell acute leukemia was made. The patient died of multiorgan failure 1 month after the onset of leukemia. As far as we know, no other such patient has been described in the English literature until now.

[Clinical analysis of 185 patients with polycythemia vera]

OBJECTIVE

To understand the clinical feature and natural course of polycythemia vera (PV).

METHODS

The clinical symptoms, signs, laboratory examination and prognosis of 185 patients with PV were analysed.

RESULTS

There are 122 males and 63 females. The mean age was (52.7 +/- 14.1) years. The mean hemoglobin level was (208.3 +/- 21.2) g/L. Pancytosis was displayed in 74 (40%) cases, excess of red blood cells in 33 (17.8%), excess of red blood cells and granulocytes in 67 (36.2%) and excess of red blood cell and platelets in 11 (5.9%). Splenomegaly was found in 123 (66.5%) patients and hepatomegaly in 30 (16.2%). Quantitative assess of serum Epo was done in 25 patients. The level was low in 16 (64.2%) and normal in 9 (36.0%). Hematopoietic progenitor culture yields was elevated in 11 patients, endogenous erythroid colonies (EEC) formation was found in 10 cases (90.9%). Eighty two patients (44.3%) had 101 attacks of vascular thrombotic incidents, 7 patients developed myelofibrosis (MF). Secondary cancer occurred in 1 patient. Two patients died of thrombosis.

CONCLUSION

PV is an elderly adult myeloproliferative disease with a high frequency of thrombosis. EEC can be found out in PV patients. The serum Epo level is not increased in PV patients. The main sequelae of PV is MF.

[The effectiveness of cyclosporin A in the treatment of autoimmune hemolytic anemia and Evans syndrome]

OBJECTIVE

To test the therapeutic effectiveness of cyclosporin A (CsA) in combination with corticosteroid in the treatment of autoimmune hemolytic anemia(AIHA) and Evans syndrome.

METHODS

Forty-four cases of AIHA and Evans syndrome were treated with CsA in combination with a conventional regimen (prednisone + danazol) (18 cases) or conventional regimen alone(26 cases).

RESULTS

The complete response rate of CsA group (88.9%) was higher than that of conventional regimen group (57.7%) (P < 0.05), and the relapse rate was lower (3.3% vs 70%) (P < 0.01).

CONCLUSION

CsA in combination with conventional regimen can improve the complete response rate and reduce relapse of AIHA and Evans syndrome.

Aldehyde and monocyclic aromatic hydrocarbon mixing ratios at an urban site in Las Vegas, Nevada

Oxidation of benzene, toluene, ethylbenzene, and xylenes (BTEX) in air, of significance due to, for example, the potential for O3 formation, is believed to be initiated by OH attack on the ring (addition) or on the alkyl side chain (H abstraction). A series of ring-breaking reactions follows, with major products predicted to be alpha-dicarbonyls, simple aldehydes, and organic acids. To test this prediction, ambient air mixing ratios of aldehydes (formaldehyde, acetaldehyde, benzaldehyde, glyoxal, and pyruvaldehyde), along with some supporting BTEX data, were measured at an urban site in Las Vegas, NV. Samples were collected on sorbents and determined by chromatographic methods; mixing ratios were compared to ambient levels of CO, O3, and NOx. A meteorological analysis (temperature, wind speed, and wind direction) was also included. Statistically significant relationships were noted among the BTEX hydrocarbons (HCs) and among the photochemically derived species (e.g., O3, NO2, and some of the aldehydes), although there was seasonal variation. The observations are consistent with a common primary source (i.e., vehicular exhaust or fuel evaporation) for the BTEX compounds and a common secondary source (e.g., OH attack) for glyoxal and pyruvaldehyde.

[Role of epithelial cell proliferation and apoptosis in human middle ear cholesteatoma]

OBJECTIVE

To determine the role of middle ear epithelial cell proliferation and apoptosis in the pathogenesis of human cholesteatoma.

METHOD

33 cholesteatoma, 25 auditory meatal skin of cholesteatoma and 10 normal human auditory meatal skin were detected by using immunohistochemistry analysis for cell proliferation with Ki 67, PCNA and PCNA antibody and TUNTEL methods for cell apoptosis.

RESULT

PCNA expression and apoptosis cells exists different quantity in cholesteatoma, auditory metal skin of cholesteatoma and normal human auditory meatal skin and distributes in various cell layer. There were positive correlation between p53 and PCNA as well as negative correlation between p53 and apoptosis.

CONCLUSION

The dyregulation of proliferation and apoptosis in keratinocyte is important in pathogenesis of cholesteatoma.

Characterization of monoclonal antibodies to glycodelin and recombinant glycodelin

Glycodelin-A belongs to the lipocalin superfamily. Although it is associated with normal endometrial growth during the menstrual cycle, fertilization and normal pregnancy in humans, the molecular mechanism of its biological action has not been elucidated. To undertake studies to understand the functional relevance of any molecule, obtaining large quantities of the protein becomes essential. With the ultimate aim of purifying glycodelin either from its natural sources (human amniotic fluid) or the recombinant glycodelin from bacterial recombinant lysates, we raised monoclonal antibodies to this protein. As immunogens, recombinant glycodelin expressed in E. coli and Pichia pastoris as well as glycodelin from amniotic fluid were used. The monoclonal antibodies generated were characterized with respect to binding to both the native as well as the recombinant proteins using ELISA, immunoblotting, and immunohistochemistry.

[A case of LGMD2A identified with both western blot analysis and immunostaining of calpain 3 in biopsied muscle]

A 45-year-old housewife had proximal dominant limb muscle weakness from around 25 years of age. Her parents were cousins. None of family members was affected. Progressive muscle weakness and atrophy were prominent at the posterior compartments of legs and trunk. Serum CK was moderately elevated. Muscle pathology revealed variation in fiber size, moderate increase in numbers of internal nuclei and abundant lobulated fibers. On immunostaining using by monoclonal antibody against human calpain 3 (NCL-CALP-2 C4; Novocastra) to the biopsied muscle, calpain 3 was completely absent in the sarcoplasm, while granular debris and in part positive striation were noted in control muscle. By Western blot analysis, a band corresponding to 94 kDa of calpain 3 was not detected. A genetic analysis of calpain 3 revealed homozygous C-565-G mutation (Leu189Val). From the present study. Western blot analysis and immunostaining by using calpain 3 antibody were suggested to be useful to diagnose LGMD2A in LGMD patients.

Nitrotyrosine causes selective vascular endothelial dysfunction and DNA damage

Vascular endothelial dysfunction is recognized as a contributor to a wide array of cardiovascular disease states, but the initiating events involved are incompletely defined. Elevated plasma levels of free 3-nitro-L-tyrosine (3NT, biomarker of peroxynitrite formation) have been measured in settings of endothelial dysfunction, but its pathologic significance is unknown. We tested the hypothesis that clinically demonstrated concentrations of 3NT can induce vascular and endothelial dysfunction in vitro. Further studies evaluated involvement of DNA fragmentation and/or apoptosis as a potential mechanism. Preincubation of rat thoracic aorta segments with 3NT (100, 250 microM) resulted in selective, concentration-dependent impairment of acetylcholine (ACH) maximal response, with no change in KCL, phenylephrine, nitroprusside, or ACH EC50 effects (ACH Emax, 53+/-2, 42+/-5, 31+/-2%; Control, 100 microM, 250 microM 3NT). Vascular segments treated with 3NT also demonstrated concentration-dependent DNA damage, assessed using DNA nick-end labeling techniques (TUNEL staining), compared with control (TUNEL-positive nuclei/linear mm: 5.4+/-1.2, 13.7+/-1.2, 16.9+/-3.2; Control, 100 microM, 250 microM 3NT), which was confined to the endothelial layer. Equimolar tyrosine had no significant effects. Frequency of positively stained nuclei was statistically correlated to extent of endothelial dysfunction (p < 0.01). Free 3NT is apparently more than a benign biomarker in vivo, and may contribute to vascular endothelial dysfunction through promotion of DNA damage and/or apoptosis.

Frequency of SCA1, SCA2, SCA3/MJD, SCA6, SCA7, and DRPLA CAG trinucleotide repeat expansion in patients with hereditary spinocerebellar ataxia from Chinese kindreds

OBJECTIVE

To assess the frequency of SCA1 (spinocerebellar ataxia type 1), SCA2, SCA3/MJD (spinocerebellar ataxia type 3/Machado-Joseph disease), SCA6, SCA7, and DRPLA (dentatorubropallidoluysian atrophy) CAG trinucleotide repeat expansions [(CAG)n] among persons diagnosed with hereditary SCA from Chinese families.

PATIENTS AND METHODS

Spinocerebellar ataxia type 1, SCA2, SCA3/MJD, SCA6, SCA7, and DRPLA (CAG)n mutation were detected with the polymerase chain reaction, highly denaturing polyacrylamide gel electrophoresis, and silver staining technique in 167 patients with autosomal dominant SCA from 85 Chinese families and 37 patients with sporadic SCA.

RESULTS

Spinocerebellar ataxia type 1 (CAG)n mutation in 7 patients from 4 kindreds (4.70%) was expanded to 53 to 62 repeats. Spinocerebellar ataxia type 2 (CAG)n mutation in 12 patients from 5 kindreds (5.88%) was expanded to 42 to 47 repeats. Spinocerebellar ataxia type 3/Machado-Joseph disease (CAG)n mutation in 83 patients from 41 kindreds (48.23%) was expanded to 68 to 83 repeats. Sixty-five patients from 35 kindreds (41.19%) and 37 patients with sporadic SCA did not test positive for SCA1, SCA2, SCA3/MJD, SCA6, SCA7, or DRPLA. There was a predictable inverse relationship between the number of CAG repeats and the age at onset for SCA3/MJD and SCA2. Clinically, dementia and hyporeflexia were more frequent in patients with SCA2, while spasticity, hyperreflexia, and Babinski signs were more frequent in patients with SCA3/ MJD, and those might be helpful in clinical work to primarily distinguish patients with SCA3/MJD and SCA2 from others with different types of SCA.

CONCLUSIONS

The frequency of SCA3/MJD is substantially higher than that of SCA1 and SCA2 in patients with autosomal dominant SCA from Chinese kindreds, who are non-Portuguese. Clinical expressions of the various types of SCAs overlap one another; therefore, for clinical study it is important to make a gene diagnosis and genetic classification for patients with SCA.

Air pollution and daily mortality in Shenyang, China

The authors analyzed daily mortality data in Shenyang, China, for calendar year 1992 to identify possible associations with ambient sulfur dioxide and total suspended particulates. Both total suspended particulate concentrations (mean = 430 microg/m3, maximum = 1,141 microg/m3) and sulfur dioxide concentrations (mean 197 = microg/m3, maximum = 659 microg/m3) far exceeded the World Health Organization's recommended criteria. An average of 45.5 persons died each day. The lagged moving averages of air-pollution levels, calculated as the mean of the nonmissing air-pollution levels of the concurrent and 3 preceding days, were used for all analyses. Locally weighted regression analysis, including temperature, humidity, day of week, and a time variable, showed a positive association between daily mortality and both total suspended particulates and sulfur dioxide. When the authors included total suspended particulates and sulfur dioxide separately in the model, both were highly significant predictors of daily mortality. The risk of all-cause mortality increased by an estimated 1.7% and 2.4% with a 100-microg/m3 concomitant increase in total suspended particulate and sulfur dioxide, respectively. When the authors analyzed mortality separately by cause of death, the association with total suspended particulates was significant for cardiovascular disease (2.1%), but not statistically significant for chronic obstructive pulmonary diseases (2.6%). In contrast, the association with sulfur dioxide was significant for chronic obstructive pulmonary diseases (7.4%), but not for cardiovascular disease (1.8%). The mortality from cancer was not associated significantly with total suspended particles or with sulfur dioxide. The correlation between sulfur dioxide and total suspended particulates was high (correlation coefficient = .66). When the authors included sulfur dioxide and total suspended particulates simultaneously in the model, the association between total suspended particulates and mortality from all causes and cardiovascular diseases remained significant. Sulfur dioxide was associated significantly with increased mortality from chronic obstructive pulmonary diseases and other causes. The results of the current study reveal increased mortality associated with both total suspended particulates and sulfur dioxide.

Stabilization and reactivation of the p53 tumor suppressor protein in nontumorigenic revertants of HeLa cervical cancer cells

We demonstrated previously that loss of in vitro transformation and in vivo tumorigenicity in two independent revertant clones of HeLa cells (designated HA and HF) resulted from dominant-acting genetic changes. Analysis of the p53 tumor suppressor gene revealed stabilization and at least partial restoration of wild-type p53 transactivation properties pathways in both revertants of HPV-induced cell transformation. The half-lives of the p53 protein and both of the HA and HF clones were increased approximately 4 fold compared with the parental HeLa cells (16, 17, and 4 min, respectively). The levels of E6 viral protein expression were similar in the three cell lines, whereas the levels of the ubiquitin ligase protein, E6 associated protein (E6-AP), were elevated in the revertants. Western blot analysis of immunoaffinity-purified p53 demonstrated that stabilization of p53 in the revertants was correlated with a reduction in the in vivo formation of complexes involving the E6 oncoprotein and p53. Stabilization of p53 function in the revertants did not result from mutations in either the p53 or E6-AP genes. Despite the observed stabilization and restoration of p53 transactivation function in the revertants, exposure of the revertants to DNA-damaging agents did not result in elevated levels of p21(waf-1) protein and failed to induce growth arrest in the G1 phase of the cell cycle. However, p53-independent induction of p21(waf-1) protein also failed to induce the G1 phase of the cell cycle. Thus, restoration of wild-type p53 transactivation activity in the HA and HF revertants is insufficient to induce G1 arrest and reversion from HPV-induced cell transformation in our model system.

Vascular peroxynitrite formation during organic nitrate tolerance

Nitroglycerin (NTG) is an important cardiovascular agent, but tolerance during continuous administration limits its clinical utility. Increased vascular superoxide production may mediate nitrate tolerance via a reduction in nitric oxide availability. Because superoxide anion and nitric oxide react avidly to form peroxynitrite, an aggressive cellular toxicant that nitrates protein tyrosine residues, we tested the hypotheses that protein nitration, indicative of peroxynitrite formation, occurs during vascular tolerance, and that protein nitration participates in tolerance development. Preincubation of rat thoracic aorta segments with NTG (22 microM, EC(95) for 30 min) caused a significant shift in NTG relaxation response (EC(50); 6.7 +/- 1.7 versus 0.50 +/- 0.13 microM, NTG versus vehicle, p <.05). After functional evaluations, tissues were fixed in formalin for immunohistochemistry and digital image analysis. NTG-induced vascular tolerance was associated with increased immunoprevalence of 3-nitrotyrosine (3NT, stable biomarker of protein nitration; 11.41 +/- 2.48 versus 0.04 +/- 0.02% positive pixels, NTG versus vehicle, p < .05). Staining was observed throughout vascular smooth muscle layers. Addition of 500 microM free tyrosine to the preincubation medium did not alter tolerance development (NTG EC(50) 6.5 +/- 3.0 microM) but abolished 3NT immunoprevalence (0.16 +/- 0.10%). No significant relationship between NTG potency and 3NT immunoprevalence was observed. These data support the hypothesis that protein nitration occurs during nitrate vascular tolerance, however, it apparently does not mediate this phenomenon.

Depolarization of membrane potential and the smooth muscle contraction by isothiocyanatobenzyl imidazoline in guinea-pig stomach circular muscle

Isothiocyanatobenzyl imidazoline (IBI) produces characteristic slowly developing contraction of many smooth muscle preparations including the circular smooth muscle of the guinea-pig stomach. Changes in the membrane potential were recorded intracellularly, and the muscle contraction induced by IBI was investigated. IBI at 100 micromol/l slowly produced a sustained depolarization of the membrane with a maximum change of approximately 15 mV. This depolarization could not be blocked by 1-hyoscyamine, 100 nmol/l. An imidazoline analogue, oxymetazoline at 1 micromol/l, did not change the resting membrane potential as observed after IBI. Significant membrane depolarization after IBI still occurred in Ca2+-free medium. During IBI-induced depolarization, sudden reduction of Na+ to 30 mmol/l in the medium reduced the depolarization slightly. IBI-induced depolarization was additive with that produced by 20 mmol/l K+ in the medium. In the presence of tetraethylammonium chloride or levcromakalim or nifedipine, IBI continued to depolarize the membrane although functional pharmacological experiments showed that the contractile effects of IBI were significantly inhibited by 30 micromol/l levcromakalim and abolished by 100 nmol/l nifedipine. At 100 micromol/l phentolamine (reported by others as an inhibitor of ATP-sensitive potassium channels) completely blocked IBI-induced contraction. Phentolamine (30 micromol/l) blocked the contractile effects of IBI by 50%. On the other hand, S(-)-Bay K 8644, a voltage-dependent calcium channel activator, was additive with the contractile response of IBI. These results indicated that IBI produced membrane depolarization and contraction of the guinea-pig stomach circular muscle, by a mechanism not involving muscarinic receptors or alpha-adrenoceptors. Even though levcromakalim, an ATP-sensitive potassium channel opener, could not inhibit IBI-induced depolarization, the ATP-sensitive potassium channel and the voltage-dependent calcium channel may be intrinsically linked with the action of IBI.

Macrophage inflammatory protein 1 alpha expression by synovial fluid neutrophils in rheumatoid arthritis

OBJECTIVE

To determine the contribution made by synovial fluid (SF) neutrophils to the augmented expression of macrophage inflammatory protein 1 alpha (MIP-1alpha) in rheumatoid arthritis (RA).

METHODS

Neutrophils were isolated from samples of SF from RA patients and peripheral blood (PB) samples from RA patients and healthy controls. Cell associated MIP-1alpha was visualised immunohistochemically, and cell associated MIP-1alpha as well as MIP-1alpha secreted into the SF was assayed by ELISA. Steady state expression of MIP-1alpha mRNA was assessed by reverse transcription polymerase chain reaction (RT-PCR).

RESULTS

Freshly isolated SF neutrophils contained significantly higher concentrations of both MIP-1alpha protein and its transcript than PB neutrophils from either RA patients or healthy controls; incubation in the absence or presence of tumour necrosis factor alpha for 24 hours resulted in a significant increase in MIP-1alpha secretion by RA SF neutrophils compared with neutrophils obtained from either normal PB or RA PB; and expression of MIP-1alpha by SF neutrophils was well correlated with both RA disease activity and SF mononuclear cell (MNC) counts.

CONCLUSION

Expression and secretion of MIP-1alpha by SF neutrophils may be indicative of local and systemic inflammation in RA. Moreover, this C-C chemokine may contribute to the recruitment of MNCs from the bloodstream into synovial joints and tissues.

[Clinico-pathological significance of the immunostaining of myosin heavy chain isoforms in pathological human skeletal muscle]

Expression of the four myosin heavy chain isoforms (fast-twitch, slow-twitch, neonatal and embryonal isoforms) was immunohistochemically observed in 500 biopsied limb muscles of neuromuscular disorders. Fast-twitch isoform was expressed in type 2A, 2B and pathologic 2C fibers. Slow-twitch isoform was expressed in type 1 and 2C fibers. Embryonic isoform was expressed in regenerating type 2C fibers of active myopathies such as Duchenne dystrophy and polymyositis. Expression of neonatal isoform, which was longer positive than that of embryonic isoform, was noted in regenerating fibers, denervated fibers and highly atrophic fibers in chronic myopathies of limb-girdle dystrophy and myotonic dystrophy. In conclusion, the immunostaining of MHC isoforms are useful to make a clinico-pathological diagnosis to determine the stages in evolution of regeneration or degeneration of pathologic muscle fiber per se.

[Determination of oridonin in Rabdosia rubescens by TLC-scanning method]

We have determingd the content of oridonin in Rabdosia rubescens Hemsl by TLC-scenning method. This method is proved to be simple, fast, precise and sensitive, and the result is stable, repetition property is good. Its rate of recovery is as high as 98.03 percent.