Strong association of antiepithelial cell antibodies with HLA-DR3 or DR7 phenotype in patients with recurrent oral ulcers

BACKGROUND

Previous studies showed that antiepithelial cell antibodies (anti-ECA) were present in 71% (15/21) of patients with recurrent oral ulcers (ROU) and that there was a strong association of human leukocyte antigen (HLA)-DRw9 with ROU in Chinese patients. In this study, we assessed anti-ECA in a larger group of Chinese patients with ROU (n = 88) in order to further investigate the association of anti-ECA with HLA-DR and -DQ antigens.

METHODS

The anti-ECA in the sera of ROU patients were detected by an indirect immunofluorescence technique with rat esophagus as the substrate, and the HLA-DR and -DQ antigens in ROU patients were typed by a standard microcytotoxicity assay using Terasaki's oriental tray.

RESULTS

The rate of anti-ECA positivity was significantly higher (p < 0.0001) in ROU patients (68%) than in healthy control subjects (0%). Furthermore, the rate of anti-ECA positivity in patients with major or minor oral ulcers (72%) was significantly higher (29%) than that in patients with herpetiform ulcers (p < 0.05). There was a significant increase in the frequency of DR3 or DR7 antigen expression (p < 0.0001, pc [p corrected] < 0.001, relative risk [RR] = 4.3, etiologic fraction = 0.41) in anti-ECA-positive ROU patients compared with the corresponding frequencies in healthy control subjects. There was also a significant increase in the frequency of DR7 or DRw9 antigen expression (p < 0.005, pc < 0.05, RR = 4.7, etiologic fraction = 0.45) compared to healthy controls.

CONCLUSIONS

Because only DR3 or DR7 antigen occurred more frequently in anti-ECA-positive than in anti-ECA-negative ROU patients (p < 0.0007, pc < 0.05, RR = 19.6, etiologic fraction = 0.51), we concluded that the gene coding for DR3 or DR7 antigen may contribute to the presence of anti-ECA in Chinese patients with ROU.

Association of HLA-te22 antigen with anti-nuclear antibodies in Chinese patients with erosive oral lichen planus

The purpose of this study was to determine the frequencies of the presence of serum anti-nuclear antibodies (ANA) and smooth muscle antibodies (SMA) in 76 patients with oral lichen planus (OLP), in 77 patients with other oral mucosal diseases, and in 41 healthy control subjects. HLA phenotypes in some of the patients with OLP and recurrent aphthous ulcers (RAU) were determined to show whether there was an association of HLA antigens with the presence of autoantibodies. Indirect immunofluorescence techniques with mouse liver or stomach as the substrate were used to detect the serum ANA or SMA, respectively. The B lymphocytes isolated from peripheral blood were used for HLA typing by means of a standard microcytotoxicity assay. We found that the positive rate of serum ANA in patients with OLP (29%, p < 0.01), especially in patients with erosive OLP (34%, p < 0.001), was significantly higher than that in the normal control subjects (5%). The frequency of serum SMA in patients with OLP (20%, p < 0.01), in patients with RAU (17%, p < 0.01), or in patients with oral squamous cell carcinomas (41%, p < 0.001) was also significantly higher than that in normal control individuals (0%). In the erosive OLP group, the HLA-Te22 antigen occurred more frequently in patients with positive ANA (75%, p < 0.05) than in those with negative ANA (25%). We conclude that there is an association of HLA-Te22 antigen with ANA in Chinese patients with erosive OLP.

Expression of p53 protein in oral submucous fibrosis, oral epithelial hyperkeratosis, and oral epithelial dysplasia

BACKGROUND AND PURPOSE

In our previous study, positive p53 staining was observed in 47 of 81 (58%) cases of oral squamous cell carcinoma associated with areca quid (AQ) chewing and cigarette smoking. This study looked for expression of p53 protein in premalignant oral lesions in patients who chewed AQ or smoked cigarettes, or both.

METHODS

Expression of p53 protein was examined in histologic sections of oral submucous fibrosis (OSF, n = 50), epithelial hyperkeratosis (EH, n = 10), epithelial dysplasia (ED, n = 10), and normal oral mucosa (NOM, n = 10) with antibodies against p53 protein using an immunoperoxidase technique.

RESULTS

Positive p53 staining was observed in 30 (60%) OSF specimens, four (40%) EH specimens, seven (70%) ED specimens, and none of the NOM specimens. Only four (8%) of the OSF specimens and none of the EH specimens had more than 25% p53-positive keratinocytes. However, in four (40%) of the ED specimens, more than 50% of the keratinocytes were p53-positive. The degree of p53 staining increased with the morphologic transformation of normal-appearing epithelial cells into dysplastic epithelial cells. There was no significant correlation between expression of p53 in OSF epithelium and the clinicohistologic parameters of patients with OSF.

CONCLUSIONS

These results demonstrate that p53 is often present in precancerous lesions of patients who chew AQ and smoke cigarettes. We suggest that p53 may play a role in dysplastic cell transformation in premalignant oral lesions.

Effects of continuous calcitonin treatment on osteoclasts derived from cocultures of mouse marrow stromal and spleen cells

BACKGROUND

Continuous calcitonin (CT) treatment for bone diseases associated with increased bone resorption may be followed by prolonged depression of osteoclast response to CT. The mechanisms of this "escape" phenomenon remain unclear.

METHODS

We examined the effects of continuous CT treatment on cell formation, calcitonin receptor (CTR) expression, response to CT, and bone resorption of osteoclasts in a coculture of mouse marrow stromal and spleen cells in the presence of 1,25-dihydroxyvitamin D3 [1,25(OH)2D3]. Cells were cocultured and treated with salmon CT (sCT) for 7, 14, or 21 days. The effects of continuous CT treatment on osteoclast formation was determined by quantitation of tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cells (MNCs). CTR expression in osteoclasts was determined by binding of [125I]sCT in autoradiography. Bone resorption and CT responsiveness were assessed by examining the formation of resorption pits and by enumerating osteoclast reattachment on dentine slices after sCT rechallenge.

RESULTS

TRAP-positive MNCs appeared in cocultures treated with sCT and were similar in number and morphology to those in control cultures, regardless of the concentration and duration of sCT treatment. A decrease in CTR expression was identified as a loss of silver grains from the TRAP-positive cells in cocultures receiving sCT treatment for 14 or 21 days. Partial recovery of CTR expression in TRAP-positive cells was evident in cocultures treated with sCT for only the first 7 days of coculture. TRAP-positive MNCs in cocultures treated with sCT for 14 or 21 days were resistant to the rechallenge with sCT. They attached to dentine slices and caused numerous resorption pits compared with control cells and cells treated with sCT for the first 7 days of coculture (p < 0.01).

CONCLUSION

These findings suggest that the escape phenomenon that develops after continuous CT treatment may be due, at least in part to: 1) loss of responsiveness to CT in existing osteoclasts; and 2) development of new osteoclasts that are CTR-deficient and, therefore, refractory to CT rechallenge.

Effects of exonuclease activity and nucleotide selectivity of the herpes simplex virus DNA polymerase on the fidelity of DNA replication in vivo

A mutagenesis system was developed for the in vivo study of the fidelity of DNA replication mediated by wild-type herpes simplex virus type 1 (HSV-1) strain KOS and its polymerase (Pol) mutant derivatives PAAr5, Y7, and YD12. The pHOS1 shuttle plasmid, which contained the SupF mutagenesis marker gene and the HSV oris sequence, was used for analysis of the mutation frequency and the mutation spectrum. All three Pol mutants induced significant increases in the mutation frequencies of the target gene, despite the fact that PAAr5 was previously shown to have an antimutator phenotype by the thymidine kinase mutagenesis assay (J. D. Hall, D. M. Coen, B. L. Fisher, M. Weisslitz, S. Randall, R. E. Almy, P. Gelep, and P. A. Schaffer, Virology 132:26-37, 1984; C. B. C. Hwang and J.-H. Chen, Gene 152:191-193, 1995). Altered spectra of mutated target genes induced by these three mutants were also observed. The relative frequencies of both deletion and complex mutations found in mutants induced by exonuclease-proficient Pols were significantly higher than those induced by exonuclease-deficient Pols. On the other hand, the exonuclease-deficient Pols induced significant increases in the frequency of base substitutions, which comprised predominantly G. C-to-T. A transversions, as well as mutations at additional hot spots. These results suggest that the HSV-1 DNA Pol can incorporate purine-purine or pyrimidine-pyrimidine mispaired bases which may be preferentially proofread by its intrinsic exonuclease activity. Furthermore, the effects of the sequence context of the target gene and the assay method should also be considered carefully in any analysis of replication fidelity.

Expression of p53 protein correlates with decreased survival in patients with areca quid chewing and smoking-associated oral squamous cell carcinomas in Taiwan

Expression of p53 protein was examined in oral squamous cell carcinoma (SCC) from patients who were areca quid (AQ) chewers and/or tobacco smokers, using anti-p53 antibodies with an immunoperoxidase technique. Positive p53 stain was observed in 47 of 81 (58%) cases of oral SCC. p53 overexpression was found to be higher in patients without AQ chewing and smoking habits than in patients with these two habits (80% vs 52%, P=0.076). No significant correlation was found between p53 expression and the patients' age, sex, cancer location, clinical staging, primary tumor TNM status, or histological differentiation of SCC. The Kaplan-Meier analysis showed that the prognosis for patients with p53-negative tumors was significantly better than that for patients with p53-positive tumors (P<0.05). A significant correlation was also observed between positive lymph node status and poor prognosis (P<0.05). These results suggest that p53 may serve as an adjuvant marker of poor survival in patients with oral SCCs in Taiwan.

[Effects of no and endothelium on carotid baroreceptor activity]

The present study was undertaken to examine the effects of endothelium and exogenous NO on the baroreceptor discharge of the carotid sinus. The baroreceptor activity (BRA) was recorded from the rabbit carotid sinus-sinus nerve (CS-CSN) preparation using a chamber for superfusing and perfusing the tissue. The results are as follows. (1) The CSN basal discharge could be divided into two components, a low-amplitude component and a high-amplitude one. The high-amplitude discharge was dependent on pulsatory perfusing pressure, but did not respond to classical chemoreceptor stimulants, indicating its baroreceptive origin. (2) The BRA was decreased after removal of the endothelium. (3) L-arginine (L-arg), as exogenous NO, initiated BRA in a dose-dependent manner, which was prevented by precedent inhibition of NO synthase or by removal of the endothelium. (4) Inhibition of guanine nucleotide cyclase with methylene blue affected neither the basal BRA nor the response of BRA to L-arg. These results indicate that stimulation of BRA by exogenous NO may be mediated by the endothelium, but cGMP dose not seem to be involved.

Anti-nicotinic properties of anticholinergic antiparkinson drugs

The nature of the antagonism by anticholinergic compounds of nicotine-induced convulsion in mice has not been defined clearly. Although, because they do not compete effectively for agonist binding to brain tissue in-vitro, these compounds are thought to be non-competitive antagonists in the brain, pharmacological evidence is lacking. This study describes the anti-nicotinic properties of the clinically used anticholinergic antiparkinson drugs, benztropine, biperiden, caramiphen, ethopropazine, procyclidine and trihexyphenidyl. Nicotine-induced convulsion and arecoline-induced tremor in mice were effectively prevented by these drugs. The concentrations of benztropine, biperiden, caramiphen, ethopropazine, procyclidine and trihexyphenidyl affording 50% prevention of nicotine-induced convulsion (ED50 values) were 7.4, 4.6, 7.8, 4.9, 3.1 and 3.3 mg kg(-1), respectively. The classical muscarinic receptor antagonist atropine had potent anti-muscarinic effects but very weak anti-nicotinic activity. The classical nicotinic receptor antagonist mecamylamine had potent anti-nicotinic activity but no anti-muscarinic effects. The pattern of shift of the dose-response curve for nicotine-induced convulsion in mice was determined in the presence of increasing concentrations of the anticholinergic antiparkinson drugs. These drugs were found to increase the ED50 (0.49 mg kg(-1)) of nicotine-induced convulsion in a dose-related manner. The maximum effect of nicotine and the slope of nicotine dose-response curve were not significantly influenced by either low or high doses of benztropine, procyclidine or trihexylphenidyl, which suggests competitive action. Biperiden, caramiphen and ethopropazine, at low doses which significantly increased the ED50 of nicotine, did not affect the maximum effect of nicotine or the slope of the nicotine dose-response curve; at higher doses, however, they reduced the maximum effect and the slope, which suggests that these drugs have both competitive and non-competitive properties in antagonizing nicotine-induced convulsion in mice. The experiments demonstrate that the anticholinergic antiparkinson drugs and mecamylamine effectively antagonize nicotine-induced convulsion, but atropine does not; some of these drugs have competitive properties whereas others seem to have both competitive and non-competitive properties in antagonizing nicotine-induced convulsion in mice.

Conditionally immortalized murine bone marrow stromal cells mediate parathyroid hormone-dependent osteoclastogenesis in vitro

PTH recruits and activates osteoclasts to cause bone resorption. These actions of PTH are thought to be mediated indirectly via type 1 PTH/PTH-related peptide receptors (PTH1Rs) expressed by adjacent marrow stromal or osteoblastic cells, although some evidence suggests that PTH may act directly on early hematopoietic osteoclast progenitors. We have established clonal, conditionally immortalized, PTH-responsive, bone marrow stromal cell lines from mice that harbor both a transgene encoding a temperature-sensitive mutant of the simian virus 40 large T antigen and deletion of a single allele of the PTH1R gene. Of 60 stromal cell lines isolated, 45 expressed functional PTH1Rs. During coculture with normal murine spleen cells, 5 of 42 such cell lines could support formation of tartrate-resistant acid phosphatase-positive, multinucleated cells (TRAP+ MNCs) in response to 1,25-dihydroxyvitamin D3, but only 2 of these did so in response to PTH. One of these, MS1 cells, expressed numerous cytokines and proteins characteristic of the osteogenic lineage and showed increased production of interleukin-6 in response to PTH. MS1 cells supported dose-dependent induction by rat (r) PTH-(1-34) (0.1-100 nM) of TRAP+ MNCs that expressed calcitonin receptors and formed resorption lacunae on dentine slices. This effect of PTH, which required cell to cell contact between MS1 and spleen cells, was mimicked by coadministration of cAMP analog and phorbol ester but only partially by either agent alone. The carboxyl-terminal fragment rPTH-(53-84) also induced osteoclast-like cell formation, but the maximal effect was only 30% as great as that of rPTH-(1-34). Importantly, rPTH-(1-34) induced TRAP+ MNC formation even when PTH1R-/- osteoclast progenitors (from fetal liver of mice homozygous for ablation of the PTH1R gene) were cocultured with MS1 cells. We conclude that activation of PTH1Rs on cells of the osteoclast lineage is not required for PTH-(1-34)-induced osteoclast formation in the presence of appropriate PTH-responsive marrow stromal cells. MS1 cells provide a useful model for further study of PTH regulation of osteoclastogenesis.

Preliminary evidence for an association of Epstein-Barr virus with pre-ulcerative oral lesions in patients with recurrent aphthous ulcers or Behçet's disease

In this study we used the polymerase chain reaction (PCR), slot blot and Southern blot hybridization, direct sequencing and in situ hybridization (ISH) to show the possible presence of EBV-DNA in pre-ulcerative oral aphthous lesions of patients with recurrent aphthous ulcers (RAU) or Behçet's disease (BD). For this purpose, formalin-fixed biopsy specimens were obtained from 13 pre-ulcerative oral aphthous lesions of nine RAU and four BD patients. Five specimens of normal oral mucosa (NOM) from five normal control subjects and 10 specimens of oral erosive or ulcerative lesions from 10 patients with erosive lichen planus (ELP) were also included. EBV-DNA was detected by PCR in 5 of the 13 (38.5%) pre-ulcerative oral aphthous lesions, two from RAU patients and three from BD patients. However, no EBV-DNA was demonstrated in five NOM specimens from normal control subjects and in 10 specimens of oral lesions from ELP patients. EBV-DNA was also demonstrated in patients' peripheral blood lymphocytes and/or plasma, suggesting that the lymphocytes may be the reservoir of latent EBV infection and there is EBV shedding in the plasma. EBV-DNA was detected by ISH in only one PCR-positive case; the reaction product was found to deposit on the nuclei of some of the epithelial cells and lymphocytes. By immunohistochemistry, expression of Epstein-Barr nuclear antigen and EBV/C3d receptors was also noted in some of the epithelial cells and lymphocytes in this ISH-positive case. Therefore, we suggest that the epithelial cells of pre-ulcerative oral aphthous lesions may be infected by EBV through EBV-infected lymphocytes; also, the cytotoxic T lymphocyte-induced lysis of the EBV-infected epithelial cells, but not the virus-induced cytolysis, may be the main mechanism causing oral ulcer formation. Our data provide preliminary evidence for an association of EBV with pre-ulcerative oral aphthous lesions in RAU and BD patients.

Effects of mutations in the Exo III motif of the herpes simplex virus DNA polymerase gene on enzyme activities, viral replication, and replication fidelity

The herpes simplex virus DNA polymerase catalytic subunit, which has intrinsic polymerase and 3'-5' exonuclease activities, contains sequence motifs that are homologous to those important for 3'-5' exonuclease activity in other polymerases. The role of one such motif, Exo III, was examined in this study. Mutated polymerases containing either a single tyrosine-to-histidine change at residue 577 or this change plus an aspartic acid-to-alanine at residue 581 in the Exo III motif exhibited defective or undetectable exonuclease activity, respectively, yet retained substantial polymerase activity. Despite the defects in exonuclease activity, the mutant polymerases were able to support viral replication in transient complementation assays, albeit inefficiently. Viruses replicated via the action of these mutant polymerases exhibited substantially increased frequencies of mutants resistant to ganciclovir. Furthermore, when the Exo III mutations were incorporated into the viral genome, the resulting mutant viruses displayed only modestly defect in replication in Vero cells and exhibited substantially increased mutation frequencies. The results suggest that herpes simplex virus can replicate despite severely impaired exonuclease activity and that the 3'-5' exonuclease contributes substantially to the fidelity of viral DNA replication.

Mechanisms of homologous and heterologous desensitization of PTH/PTHrP receptor signaling in LLC-PK1 cells

Parathyroid hormone (PTH) activates multiple intracellular effectors, including adenylyl cyclase (AC) and phospholipase C (PLC), via a single receptor [PTH/parathyroid hormone-related protein receptor (PTHR)] expressed in bone and kidney. Homologous desensitization of PTHR signaling occurs, but the relative importance of reduced receptor expression vs. impaired receptor-effector coupling in this process remains unclear. It also is not known if AC and PLC responses to PTH are desensitized independently or interdependently. In LLC-PK1 cells that expressed transfected wild-type PTHRs, PTH caused dose- and time-dependent desensitization of both the AC and PLC-responses to PTH without altering PTHR expression. Desensitization of AC was blocked in mutant cells resistant to adenosine 3',5'-cyclic monophosphate but not when cells expressed mutant PTHRs with defective PLC coupling. Desensitization of PLC was unaffected by PKA blockade, partially mimicked by phorbol ester, and not reproduced by agents that selectively activated AC. The finding that homologous PTHR desensitization in LLC-PK1 cells is signal specific suggests that prior exposure of other cells to PTH also may induce discordant regulation of subsequent PTHR signaling, altering the character as well as the intensity of the hormonal response.

Anticholinergic activity in mice and receptor-binding properties in rats of a series of synthetic tropane derivatives

A tropane ester, three tropane ethers, atropine and mecamylamine were compared in mice for their anti-muscarinic and anti-nicotinic activity against arecoline-induced tremor and nicotine-induced convulsions, respectively. Their receptor-binding characteristics were studied in neuronal membranes prepared from rat cerebral cortex. The results showed that the tropane ester, 2 alpha R-tropanyl benzylate, was more potent than atropine in its anti-muscarinic activity, but the anti-muscarinic activity of the tropane ethers, 2 alpha-(2',2'-diphenyl-2'-hydroxy-ethoxy)tropane (alpha-DPT) and its two isomers (1R,2 alpha R- and 1S,2 alpha S-) were less potent than that of atropine. In contrast with their anti-muscarinic potency, 2 alpha R-tropanyl benzylate and the three tropane ethers were equipotent in their anti-nicotinic activities. The order of potencies of these compounds to displace the binding of [3H]quinuclidinyl benzylate to brain membranes was similar to that of their anti-muscarinic potencies. The binding of [3H]nicotine to nicotinic receptors from brain was not inhibited by these compounds. Analyses of structure-activity relationships of these compounds suggested that it is the ester groups that determine the anti-muscarinic potencies of 2 alpha R-tropanyl benzylate; their anti-nicotinic activities were independent of the structural changes and of the anti-muscarinic activities of these compounds.

Human cytomegalovirus as a potential etiologic agent in recurrent aphthous ulcers and Behçet's disease

In a preliminary study on anti-human cytomegalovirus (HCMV) antibody (Ab) by ELISA, the serum anti-HCMV/IgG Ab concentrations in 22 patients with recurrent aphthous ulcers (RAU) in the remission stage were found to be significantly higher than in 22 control subjects (121 +/- 42 vs 100 +/- 27, P < 0.05) and in 39 patients with RAU in the active stage (121 +/- 42 vs 88 +/- 45, P < 0.01). Therefore, the potential of HCMV as an etiologic agent in RAU was proposed and studies using the polymerase chain reaction (PCR) and in situ hybridization (ISH) have been performed to investigate the possible presence of HCMV DNA in pre-ulcerative oral aphthous lesions in patients with RAU or Behçet's disease (BD) of the mucocutaneous type. For this purpose, formalin-fixed biopsy specimens were obtained from 13 pre-ulcerative oral aphthous lesions, 2 samples of normal oral mucosa and 1 ileal mucosal lesion from 9 RAU patients and 4 BD patients. Five specimens of normal oral mucosa from 5 normal control subjects and 12 specimens of oral erosive or ulcerative lesions from 12 patients with erosive lichen planus (ELP) were also included. By PCR, HCMV DNA was detected in 5 of the 13 (38.5%) pre-ulcerative oral aphthous lesions, 3 from RAU patients and 2 from BD patients. The ileal mucosa specimen was also HCMV DNA-positive, whereas HCMV DNA was not demonstrated in any of the 7 specimens of normal oral mucosa from RAU patients and normal control subjects; 12 specimens of oral lesions from ELP patients were similarly negative. ISH did not detect HCMV DNA in any of the biopsy specimens from RAU patients and control subjects. Our findings suggest that HCMV may be an etiologic agent in some cases of RAU and BD.

Adherence patterns and DNA probe types of Escherichia coli isolated from diarrheal patients in China

One hundred and seventy-two strains of Escherichia coli isolated from diarrheal patients in Beijing, P.R. China, were analyzed for plasmid DNA profile, HEp-2 cell adherence ability and reactivity to 10 previously described DNA probes. They had not been recognized as pathogenic E. coli in China. Of the 110 strains tested, 76 (69%) contained one or multiple large plasmids. Of the 71 strains with the large plasmids 64 could adhere to HEp-2 cells. Of the 172 strains, 102 (59.3%) were hybridized with at least one of the 10 probes. Of those, seven strains hybridized with enteroaggregative E. coli (EAggEC) probe. Their serotypes were O128 (two strains), O6 (one strain), and O111 (one strain). Three strains were untypable. Six and three strains were hybridized with enteropathogenic E. coli (EPEC) attaching and effacing genes (eae) or EPEC adherence factor (EAF) probe, respectively. Two non-O157: H7 strains hybridized with enterohemorrhagic E. coli (EHEC) probe. Seventy-two strains (41.9%) hybridized with shiga-like toxin 2 or 1 (SLT2 or SLT1) probes. Among the SLT1 or SLT2 probe-positive strains, 54 hybridized with invasive (INV) plasmid probe developed for identification of enteroinvasive E. coli (EIEC) and Shigella species. The INV and SLT probe-positive strains might represent a new variety of verotoxin-producing E. coli (VTEC).

Secondary dentin deposition in dens evaginatus: report of a case

An unusual case of dens evaginatus in a 22-year-old man is reported. The involved tooth was the right upper second premolar which appeared to have been segregated into coronal and apical segments during the disease process. Although abscess formation was noted in the coronal portion, continuing secondary dentin deposition was found over the displaced apical segment. The pathogenesis of this unusual dentinal bridge formation is proposed based on the microscopic and radiographic findings.

[A study on the level of antibody against measles through maternal-fetal transfer and the immuno-response to measles vaccine among 4 to 7 month olds]

A total number of 143 infants at the age of 4 to 7 months from Yantai city-Shandong was selected for the study of antibody level against measles by maternal-fetal transfer and immuno-response to measles vaccine in October of 1993. The results showed that the negative rates of maternal-fetal antibody among infants of 4, 5, 6 and 7 month olds were 75.00%, 81.25%, 94.87% and 90.1%, respectively. The positive rates and geometric mean titers (GMTs) for immuno-response to measles vaccine were 92.86%, 84.38%, 97.44%, 100.00% and 55.17, 42.41, 69.95, 71.46, respectively. There were significant lower immune response to measles vaccine in infants who had high titer ( > 1:2) than those who had low titer ( <or= 1:2) of maternal-fetal antibody (chi 2 = 88.38, P < 0.001). In order to decrease the number of measles cases under 1 year old (especially under 9 month-old), the author suggested that the primary immunization for measles vaccine should be started at 6 month olds.

[Refractory periods of cardiac tissues and the filtering properties of the atrioventricular node in the isolated rabbit heart]

It is generally believed that the atrioventricular node (AVN) possesses filtering properties (FP) capable of preventing excess atrial impulses or earlier atrial premature beat from reaching the ventricle. In the present study, the refractory periods (RP) of cardiac tissues and the FP of the AVN were investigated in isolated rabbit hearts (n = 18). It was found that: (1) The relative RP of AVN was the longest at shorter basic cycle lengths (BCL) (200-300 ms) while the relative RP of His-Purkinje system (HPS) was the longest at longer BCL (600, 700 ms). (2) The effective RP of AVN was shorter than the functional RP of the atrium in most cases (16/18) at any BCL. (3) During rapid atrial pacing at cycle length of 140 ms in 7 cases, AVN maintained 1:1 conduction. (4) The atrioventricular nodal conduction curve was smooth at BCL from 200 to 700 ms. The present results suggest that AVN in the isolated perfused rabbit heart do not have the FP and any dual atrioventricular pathways in a physiological sense.

Percutaneous endoscopic polypectomy of gallbladder polyps

We report here our preliminary experience with percutaneous endoscopic polypectomy of gallbladder polyps. Five patients with a total of 17 cholesterol polyps (size: 4-6 mm) and one patient with two gallbladder adenomas (size: 5 mm), four of whom were symptomatic and all of whom refused cholecystectomy, underwent a single-stage procedure under epidural anesthesia. All patients had functioning gallbladders, as assessed by oral cholecystography after stimulation. Following a small incision, the gallbladder was pulled out of the abdominal wall, incised, and a cholecystoscope introduced. The polyps were coagulated at their stalk using microwave irradiation (70-80 mA, 9 sec) and removed for histopathological evaluation thereafter. A catheter was left in situ for ten days. Follow-up for a mean of 11.6 months (8-16 months) showed all patients to be symptom-free and without recurrence of polyps on ultrasonography. Gallbladder function was assessed in five cases by meal-stimulated oral cholecystography, and in one by hepato-iminodiacetate acid (HIDA) scan and was found to be well preserved. The preliminary results warrant further evaluation of this method of removing indeterminate gallbladder polyps.

Oral post-radiation malignant fibrous histiocytoma: a clinicopathological study

Five cases of oral malignant fibrous histiocytoma (MFH) in patients who had previously received radiotherapy in the head or neck region were included in this study. There were 3 men and 2 women. Four patients had been irradiated for nasopharyngeal carcinoma (NPC) and the other for a squamous cell carcinoma (SCC) involving the tongue and mouth floor. The MFH developed 2.5-11 years after the initial radiotherapy. Two cases of MFH occurred in the maxilla, two in the mandible, and the remaining one in the tongue, floor of mouth and mandible. Clinically, the oral post-radiation MFH presented as tender, reddish, elastic, lobulated masses with surface ulceration. Radiographic examination of the involved jaws revealed a poorly defined radiolucent lesion without any periosteal or endosteal reaction. The prognosis of these tumors was very poor. Although aggressive multimodality treatment had been applied, 3 of 5 patients eventually died of the disease, with a mean survival time of 17 months after establishing the diagnosis of MFH. In order to ensure the early diagnosis and treatment of this radiation-induced second malignancy, close oral follow-up is mandatory for patients who have received radiotherapy for head and neck malignancies.

[Study and application of dual interventional embolization in patients with acute gastroesophageal variceal bleeding]

From Nov. 1991 to Nov. 1992, twelve cases of acute massive gastro-esophageal variceal bleeding with liver function grading III had been treated with dual interventional embolization (DIE). Hemostasis were successful in all patients during the acute phase. Ten partial splenic embolization (PSE) cases with their hypersplenism cured or improved. The liver function in survived cases were improved with various degree after DIE. The mechanism of DIE in the treatment of acute gastro-esophageal variceal bleeding had been discussed and the alterations in portal pressure, the histopathology of the spleen, the peripheral hematologic changes as well as the complications after DIE were analysed and discussed. The authors claimed that DIE is an alternative method in treating the advanced cirrhosis complicating massive variceal bleeding.

Immunomodulation by levamisole in patients with recurrent aphthous ulcers or oral lichen planus

The purpose of this study was to evaluate the effect of levamisole on the immune system of patients with recurrent aphthous ulcers (RAU) or oral lichen planus (OLP) in an open trial. Lymphocyte subsets, serum immunoglobulins, and circulating immune complexes (CIC) in patients with RAU or OLP and in normal control subjects were determined by an indirect immunofluorescence (IIF) technique with monoclonal anti-lymphocyte antibodies, by single radial immunodiffusion, and by precipitation with 3% polyethylene glycol, respectively. In addition, the anti-nuclear antibodies (ANA) and anti-basal cell antibodies (anti-BCA) in sera were detected by an IIF technique. We found a significant improvement in clinical symptoms and normalization of the decreased CD4/CD8 ratio in RAU patients after levamisole treatment. Moreover, the decreased CD4/CD8 ratio, which persisted until the remission stage in the untreated RAU patients, reverted to normal in the active late stage in the levamisole-treated patients. This reversion of aberrant cellular immunity in an earlier stage of the ulcer cycle may explain why RAU patients experience symptom improvement after levamisole treatment. Although RAU patients treated with levamisole for 1 to 3 or 4 months still had higher than normal levels of CIC and serum immunoglobulins, the levels of their IgA and IgM returned to normal values after 4 months of levamisole treatment. The serum ANA detected in 6 patients with RAU and 3 patients with erosive OLP disappeared after 1-22 months of levamisole treatment. The disappearance of serum anti-BCA was also observed in 50% of the anti-BCA-positive patients with erosive OLP after 3-13 months of levamisole treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Hyaline ring granuloma: a case report with histochemical and polarized microscopic studies

An unusual case of hyaline ring granuloma arising from the connective tissue wall of a residual apical periodontal cyst is reported. Hyaline rings with foreign-body type giant cell inclusions were a significant feature in the histopathologic diagnosis. Histochemical and polarized light microscopic studies suggested that the introduction of foreign material, possibly cellulose, through the postextraction socket into the cystic wall may have caused the granulomatous reaction and formation of the hyaline ring granuloma. The clinical features of this case and 66 previously reported cases, as well as the pathogenesis of the hyaline rings, are discussed.

Experimental infection of specific-pathogen-free mice with enterohemorrhagic Escherichia coli O157:H7

By subcutaneous inoculation of 10(8) CFU of enterohemorrhagic E. coli O157:H7, specific-pathogen-free mice revealed most of the symptoms and histological changes observed in patients. The histological changes in intestine were mainly seen in the distal parts of small intestine and the cecum. Vacuolation of villi in the cecum was also observed. The histological changes in the kidneys of the infected mice were featured as the swollen epithelial cells of glomeruli and the marked thickening of glomerular capillaries with barely visible lumens. Unexpected findings in the bronchiole were characterized by sloughing of the epithelial cells of bronchiolar wall, leading to partial or complete obstruction of the lumens. Histological changes in the spleen, liver and lymphnodes were also observed. The bacteria were recovered from the feces, contents of small intestine, and samples taken from kidney, liver, heart, spleen, different parts of small intestine, cecum, and colon. By using peroxidase-antiperoxidase (PAP) assay with polyclonal antibodies against "O" antigen of E. coli O157:H7, it was observed that the samples taken from the brain, kidney, ileum, cecum, spleen, and liver gave positive reactions. Feces and contents of small intestine obtained from all of the infected animals were positive by occult blood test. These results show that the experimental infection of E. coli O157:H7 in this model is systemic in nature.

Detection of human papilloma virus (HPV) in laryngeal carcinoma tissue

Using alpha-32P-dCTP labelled human papillomavirus type 16 DNA genome probe (cHPV 16 DNA, cloned and identified from a Chinese cervical invasive carcinoma), 3 HPV 16 genomic relative sequences were detected in 6 biopsies of laryngeal carcinoma. The results showed serious HPV infection in laryngeal carcinoma. This indicates that HPV infection may play an important pathogenetic role in cancer development.

[Hypoxaemia during transportation of patients after anesthesia and upper abdomen surgery]

The incidence of hypoxaemia was studied in 100 patients breathing room air during their transportation from the operating room to the recovery room. Hypoxaemia (SaO2 less than 90%) occurred in 24 (24%) patients. Oxygen saturation rose quickly above 95% when oxygen was administered. The causes of hypoxaemia are discussed. Quick transportation and oxygen supply were recommended.

[Effects of extracellular sodium concentration on the sodium-pump activity in Purkinje fibres of sheep]

Intracellular sodium activity (aiNa), extracellular potassium activity (aok) and resting membrane potential (Vm) were measured in sheep cardiac Purkinje fibres exposured intermittently to calcium-free solution containing different concentrations of low sodium. In Ca-free low sodium solution, aiNa decreased, the rates and amplitudes of aiNa changes were related to [Na]o linearly. The linear correlation between the stable values of aiNa (aiNa(S)) at 6th minute of aiNa decrease and [Na]o meant that the amplified active Na+ extrusion and pump current resulting from decreased [Na]o, kept finally Na+ gradient across the membrane relatively stable. Hence, it was proposed that it was the Na+ gradient across the membrane but not the internal Na+ that regulated the sodium pump activity. The membrane hyperpolarization which was incident with the increase of active Na+ extrusion was caused mainly by the amplified pump current and embellished by the intercellular K+ depletion and accumulation simultaneously, which was suggested by the mutual relation of time courses of changes in aiNa, Vm, aok during the exposure of the fibre to 1.3Na Ca-free solution.

Three wishes of a child with cancer

Thirty-seven children in Taiwan with cancer, ranging in age from 4 to 16 were asked to identify their three wishes. Nearly three-quarters of the total sample "wished" to go home from the hospital and 90% used one of their wishes in hopes to be cured. Preschool youngsters were more eager to resume play activities (64%), to go home (36%), and to own some desired object (36%); while school-age children hoped primarily to be cured (44%), to go home (39%) and to have more physical exercise (28%). Adolescents wished to have their disease cured (100%), return to school (63%) and to go home (37%). Gender differences seemed to have little impact on the wishes of children. The following study underscores the need for nurses to understand the hopes and dreams of children with cancer in order to work with these children toward their own envisioned futures while making the present as least traumatic as possible. Indeed, such mutual goal-setting is at the heart of the therapeutic nursing process for clients of any age and any culture.

[Preliminary study on the nucleic acid hybridization technic in detecting HSV-2 DNA corresponding sequence of cancer tissues of the uterine cervix]

In this paper, 34 samples, 25 from 18 cervical carcinoma patients and 9 from 8 non-cervical carcinoma patients, were assayed using (alpha-32P) dCTP HSV-2 DNA probe and nucleic acid hybridization technic. It was shown that the positive rates of HSV-2 DNA corresponding sequence were 50% (2/4), 36% (5/14) and 12% (1/8) in the in situ cancer, invasive cancer and non-cervical cancer tissues. No HSV was isolated from 7 cancer specimens which showed a positive reaction by nucleic acid hybridization.

Preparation of large temporomandibular joint specimens for pathological study

Ten fresh temporomandibular joint (TMJ) specimens about 5 X 4.5 X 3.5 cm in size were removed at autopsy by 5 cuts according to appropriate anatomical landmarks. After routine formalin fixation, the whole-TMJ specimens were wrapped with a thin layer of self-curing resin and then cut with a low speed bone saw along the parasagittal plane predetermined by x-ray guidance. Each specimen was serially cut into 4 to 5 parallel slices of 3 mm thickness, which were then decalcified with 14% EDTA and embedded in paraffin. Histological sections of 5 microns were stained with hematoxylin and eosin. The procedures were accomplished within 20 to 24 days after autopsy. With this technique, the anatomical interrelationships among the various joint components could be maintained and the macroscopic and microscopic topography of the TMJ could be studied in the desired reference plane. Therefore, the corresponding changes among the joint components in a diseased TMJ could be thoroughly examined. This technique was also applicable for the study of large specimens containing both hard and soft tissues.

A criterion for accurate aerosol sampling in calm air

The problem of aerosol sampling under calm air conditions has been studied by solving the Navier-Stokes equations and integrating the equations of particle motion. Both particle inertia and settling are considered. The sampling efficiency of an inlet has been found to depend on two dimensionless parameters, the Stokes number and the relative settling velocity. A new criterion for accurate aerosol sampling in calm air is then derived. Experimental data of several researchers are discussed in the light of this new sampling criterion, and the data are found to be in accord with the theoretical predictions.

A dust generator for laboratory use

A dust generator has been developed to produce dry dust from powderous materials for instrument calibration and laboratory studies. The powder is fed at a constant rate via a chain conveyor into a fluidized bed where the particles are deagglomerated and aerosolized. The powder feed rate is raviable from 1.2 to 36 mm3/min and the air flow rate from 9 to 30 Lpm. Aerosols of coal, silica, potash, rock, and Arizona road dust have been successfully generated for calibrating optical particle counters and aerosol mass monitors.

An aerosol generator of high stability

This paper reports on the use of a syringe pump to provide a constant liquid flow to an atomizer to obtain an aerosol generator of high stability. This syringe-pump atomizer has also been used with a vaporizer-condenser to generate monodisperse DOP (di-octyl phthalate) aerosols in the 0.032 to 1 mum diameter range.