Effective dose of intranasal remimazolam for preoperative sedation in preschool children: a dose-finding study using Dixon's up-and-down method

Background

Most preschool children are distressed during anesthesia induction. While current pharmacological methods are useful, there is a need for further optimization to an "ideal" standard. Remimazolam is an ultra-short-acting benzodiazepine, and intranasal remimazolam for pre-induction sedation may be promising.

Methods

This study included 32 preschool children who underwent short and minor surgery between October 2022 and January 2023. After pretreatment with lidocaine, remimazolam was administered to both nostrils using a mucosal atomizer device. The University of Michigan Sedation Score (UMSS) was assessed for sedation 6, 9, 12, 15, and 20 min after intranasal atomization. We used Dixon's up-and-down method, and probit and isotonic regressions to determine the 50% effective dose (ED50) and 95% effective dose (ED95) of intranasal remimazolam for pre-induction sedation. Results: Twenty-nine pediatric patients were included in the final analysis. The ED50 and ED95 of intranasal remimazolam for successful pre-induction sedation, when processed via probit analysis, were 0.65 (95% confidence interval [CI], 0.59-0.71) and 0.78 mg/kg (95% CI, 0.72-1.07), respectively. In contrast, when processed by isotonic regression, they were 0.65 (95% CI: 0.58-0.72 mg/kg) and 0.78 mg/kg (95% CI: 0.69-1.08 mg/kg), respectively. At 6 min after intranasal remimazolam treatment, 81.2% (13/16) of "positive" participants were successfully sedated with a UMSS ≧ 1. All the "positive" participants were successfully sedated within 9 min.

Conclusion

Intranasal remimazolam is feasible for preschool children with a short onset time. For successful pre-induction sedation, the ED50 and ED95 of intranasal remimazolam were 0.65 and 0.78 mg/kg, respectively.

Synthesis, antitumor and antibacterial activities of cordycepin derivatives

Twelve novel cordycepin derivatives were designed and synthesized with modification at positions of 2', 5'-hydroxyl and N⁶ amino groups of cordycepin. The results showed that the inhibitory activities of 3, 4b, 6c and 6d on A549 were comparable to the positive control gefitinib, and the inhibitory activity of 6a on A549 was better than that of gefitinib. Also, the inhibitory activities of twelve cordycepin derivatives against E. coli 1924, S. aureus 4220 and S. mutans 3289 were studied. Among them, 4b showed certain inhibitory on S. mutans 3289, while 6b showed certain inhibition on S. aureus 4220.

Efficient decomposition of perfluorooctane sulfonate by electrochemical activation of peroxymonosulfate in aqueous solution: Efficacy, reaction mechanism, active sites, and application potential

The electrochemical oxidation method is a promising technology for the degradation of perfluorooctane sulfonate (PFOS). However, the elimination processes of PFOS are still unknown, including the electron transfer pathway, key reactive sites, and degradation mechanism. Here, we fabricated diatomite and cerium (Ce) co-modified Sb₂O₃ (D-Ce/Sb₂O₃) anode to realize efficient degradation of PFOS via peroxymonosulfate (PMS) activation. The transferred electron and the generated hydroxyl radical (•OH) can high-effectively decompose PFOS. The electron can be rapidly transferred from the highest occupied molecular orbital of the PFOS to the lowest unoccupied molecular orbital of the PMS via the D-Ce/Sb₂O₃ driven by a potential energy difference under electrochemical process. The active site of Ce-O in the D-Ce/Sb₂O₃ can greatly reduce the migration distance of the electron and the •OH, and thus improving the catalytic activity for degrading various organic micropollutants with high stability. In addition, the electrochemical process shows strong resistance and tolerance to the changing pH, inorganic ions, and organic matter. This study offers insights into the electron transfer pathway and PMS activation mechanism in PFOS removal via electrochemical oxidation, paving the way for its potential application in water purification.

Exploration of perfluorooctane sulfonate degradation properties and mechanism via electron-transfer dominated radical process

Polyfluoroalkyl and perfluoroalkyl chemicals (PFCs) widely used in lubricants, surfactant, textiles, paper coatings, cosmetics, and fire-fighting foams can release a large deal of organics contaminants into wastewater and pose great risks to the health of humans and eco-environments. Although advanced oxidation processes can effectively deconstruct various organic contaminants via reactive radicals, the stable structure of PFCs makes it difficult to be degraded. Here, we confirm that electrochemical oxidation process coupled with peroxymonosulfate (PMS) reaction can efficiently destroy stable structure of PFCs via electron transfer and meanwhile completely degrade PFCs via generated active radicals. We further studies via capturing and scavenging radicals, and DFT calculations find that electron hydroxyl radials play a dominant role in degrading PFCs. Based on the calculations of adsorption energy and molecular orbital energy we further demonstrate that many active sites on the surface of Ti₄O₇ (1 0 4) plane can rapidly take part in electrochemical reaction for generating radials and removing organic contaminants. These results give a promising insight towards high-effective and deep degradation of PFCs via electrochemical reaction coupled with advanced oxidation processes, as well as providing guidance and technical support for the remove of multiple organic contaminants.

[Studies on lithium in the environment and its effects on the central nervous system]

This paper introduces the distribution of global lithium resources and absorption, distribution, metabolism and excretion of lithium in the human body, discussing the positive effect of lithium in the environment on the nervous system and its neuroprotective mechanism. The tiny amounts of lithium that enter the body through the food chain have been linked to beneficial health effects, such as improved cognition and reduced depression and violence. However, the safe dose range of lithium is narrow, and the health effects of drinking high concentrations of lithium water in high-lithium areas are unclear. It is necessary to study the health effects and mechanisms of different doses of lithium, especially high concentrations of lithium in the environment.

[Tree species identification of wooden funeral utensil from Qing Dynasty's tombs and its potential of ecological and environmental indicator in Shenyang, Northeast China]

The wood used for funeral utensil in ancient tomb is a kind of valuable materials and important for understanding vegetation, climate and society conditions in the history. Here, we identified the tree species and dated the time of wooden utensils for funeral excavated from tombs in Shuijia Village, Shenyang, using wood anatomy methods and dendrochronological techniques. The results showed that 7 out of the 16 wood samples were identified as Pinus tabuliformis from Pinaceae, 8 were Larix sp. from Pinaceae and most likely Larix olgensis, and the rest one was Acer sp. from Aceraceae. Currently, these tree species are still widely distributed in Liaoning Province, indicating that forest structure (tree species composition) is relatively stable and that the climate at that time was quite similar to that at present. The timbers used for wooden utensils of funeral for civilian tombs had regional biogeographic characteristics and reflected regional social productivity development level in Mukden (now Shenyang) in Qing Dynasty: most of them were native tree species with low cost and high availability; the main timber trees were conifer species, and a few of them were broadleaved trees. These timbers were likely from the forest in Shenyang or mountainous areas in Eastern Liaoning, with Hunhe River waterway being an important transport way for timbers to Shenyang. Some P. tabuliformis and Larix sp. timbers could be cross-dated well, and the growth period of the trees was determined to be 1680s-1770s (early to mid-Qing Dynasty). The variations of tree-ring width of these timbers had good consistency and high climate sensitivity, reflecting the consistency of regional climate and environment. These timbers have the potential to indicate the climate condition of the early to mid-Qing Dynasty.

[Warming-drying climate intensifies the restriction of moisture on radial growth of Pinus tabuli-formis plantation in semi-arid area of Northeast China]

Plantation ecosystems are more vulnerable than natural ones to global climate change. Using the dendrochronology method, we established tree-ring width chronologies of Pinus tabuliformis distributed in the semi-arid region of Northeast China. We examined its growth dynamics, analyzed the relationship between radical growth and climate factors, and explored the effects of global warming on the growth and distribution of P. tabuliformis. The results showed that tree-ring width chronologies of P. tabuliformis were negatively correlated with mean temperature of growing season (May-July), and positively correlated with precipitation and Palmer drought severity index (PDSI) in the early growing season (April) and in the growing season (May-July). Water availability was the main limiting factor for the radial growth of P. tabuliformis. Along the increasing precipitation gradient from southwest to northeast, tree growth became more sensitive to annual mean temperature, and the correlation with annual precipitation shifted from positive to negative, indicating that tree growth in the relative arid area (southwest of the study area) was more severely restricted by water availability. Drought stress caused by climate warming resulted in growth declines at some sites in the southwest area. With the continuous warming-drying climate, the distribution boundary of P. tabuliformis in the study area would shrink locally, with the suitable growth boundary moving northward.

[Effects of Straw Returning with Chemical Fertilizer on Soil Enzyme Activities and Microbial Community Structure in Rice-Rape Rotation]

Straw returning is an effective technique for improving soil fertility and maintaining crop productivity in agro-ecosystems. The effects of straw returning, when combined with chemical fertilizer, on soil nutrients, enzyme activity, and microbial community were explored in rice-rape rotation farmland in the Chaohu Area. We carried out a 4-year field experiment (2016-2020) and set up four treatments (no straw+no fertilization, CK; conventional fertilization, F; straw returning+conventional fertilization, SF; and straw returning+conventional fertilization minus 20%, SDF) to explore the key environmental factors affecting soil enzyme activity and microbial and fungal communities. The results showed that straw returning combined with chemical fertilizer could improve soil nutrient content, with the SF treatment resulting in the highest soil nutrient content. Compared with F, the SF treatment significantly increased the organic matter (OM) and total phosphorus (TP) content of the soil, by 7.94% and 24.07%, respectively, in rice seasons (P<0.05), while the alkaline nitrogen (AN) content was significantly increased by 13.62% in rape seasons (P<0.05). Compared with F, the SF treatment also significantly increased soil phosphatase and urease, by 28.54% and 24.13% in rice seasons and 38.97% and 30.70% in rape seasons, respectively (P<0.05). Compared with F, SDF treatments significantly increased urease activity by 20.31% in rice seasons and 24.33% in rape seasons (P<0.05). The results indicated that straw returning increased both the Chao1 and Shannon indices of soil bacteria in rice seasons, whereas decreased these indices in rape seasons. However, the Chao1 and Shannon index of the fungal community increased after straw returning. In terms of microbial community structure, the relative abundance of Proteobacteria in SF and SDF treatments increased by 8.22% and 7.88% in rice seasons and 18.53% and 5.68% in rape seasons, respectively, compared with the F treatment. Compared with F, the relative abundance of Chloroflexi in SF and SDF treatments increased by 12.00% and 11.25% in rice seasons and 15.02% and 8.43% in rape seasons, respectively. Compared with F, the relative abundance of Basidiomycota in SF and SDF treatments in rice seasons increased by 70% and 43.42% (P<0.05), respectively, while ascomycetes in rape seasons increased by 69.79% and 43.72% (P<0.05), respectively. In conclusion, straw returning combined with chemical fertilizer can improve soil nutrient content. Soil urease and phosphatase were more sensitive to straw returning. The compositional changes in the bacterial community of the soil were mainly affected by soil TP and available phosphorus (AP), whereas OM, AN, and pH were the main environmental factors causing changes in the fungal community composition. Consequently, straw returning can improve soil fertility and maintain ecosystem health.

[Altitudinal differentiation in the radial growth of Betula platyphylla and its response to climate in cold temperate forest: A case of Oakley Mountain, Northeast China]

Climate change has profound impacts on the structure and function of forest ecosystem. Under the background of climate warming, the growth patterns and climate responses of different species in different environments determine the development and stability of ecosystems. Using the method of tree chronology with ring width data of Betula platyphylla in Oakley Mountain of Daxing'an Mountains, we examined the relationship between the growth climate response of the pioneer B. platyphylla in larch forest and temperature rise and altitudinal changes. The results showed that climate warming resulted in the differentiation on B. platyphylla in different altitude. The radial growth of B. platyphylla increased significantly at the low altitude area (1050 m), while there were little changes at the relatively high altitude area (1250 m). Before the time of rapid warming (1980), the radial growth of B. platyphylla on two altitude areas were significantly stressed by low temperature in winter (October to February). During the period of rapid warming (1981-2010), low temperature stress in winter did not affect tree growth, with the growing season (May to July) temperature becoming the main limiting factors to the radial growth of B. platyphylla at the relatively high altitude areas. The growth of B. platyphylla increased in the low altitude stands with favorable water and heat conditions. The distribution of B. platyphylla may generally spread to high altitude sites in the study area under climate warming.

Prevention of necrotizing enterocolitis in premature infants – an updated review

Necrotizing enterocolitis (NEC) is among the most common and devastating diseases encountered in premature infants, yet the true etiology continues to be poorly understood despite decades of research. Recently, gut bacterial dysbiosis has been proposed as a risk factor for the development of NEC. Based on this theory, several best clinical practices designed to reduce the risk of NEC have been proposed and/or implemented. This review summarizes the results of recent clinical trials and meta-analyses that support some of the existing clinical practices for reducing the risk of NEC in premature infants. It is evident that human milk feeding can reduce the incidence of NEC. While most of the studies demonstrated that probiotic supplementation can significantly reduce the incidence of NEC in premature infants, there are still some concerns regarding the quality, safety, optimal dosage, and treatment duration of probiotic preparations. Antibiotic prophylaxis does not reduce the incidence of NEC, and prolonged initial empirical use of antibiotics might in fact increase the risk of NEC for high-risk premature infants. Lastly, standardized feeding protocols are strongly recommended, both for prevention of postnatal growth restriction and NEC.

[Advances on the research of the environmental risk factors of children autism]

Autism spectrum disorder is a lifelong neurodevelopmental disorder, characterized by social interaction and communication impairments, accompanied by repetitive behaviors. Little is known about the causes and contributing factors for autism. It is difficult to prevent and cure, and has become a globe public health problem. With the development in the prevalence of autism, the idea how the environmental factors cause the autism, gains all attentions. Summarizing latest epidemiological studies and experimental evidence, this review is focused on the effect of environmental factors, including air pollutant, heavy metal and pesticides, and discussed the relation between environmental risk factors and autism. The results showed that risks of autism in children may increase following in prenatal exposure to air pollutants, heavy metal and pesticides. It is needed to do the research on the mechanism of environmental risk factor and autism for more prevention, treatment and control suggestions.

A PCR Method That Can Be Further Developed into PCR-RFLP Assay for Eight Animal Species Identification

There are many PCR-based methods for animal species identification; however, their detection numbers are limited or could not identify unknown species. We set out to solve this problem by developing a universal primer PCR assay for simultaneous identification of eight animal species, including goat, sheep, deer, buffalo, cattle, yak, pig, and camel. In this assay, the variable lengths of mitochondrial DNA were amplified using a pair of universal primers. PCR amplifications yielded 760 bp, 737 bp, 537 bp, 486 bp, 481 bp, 464 bp, 429 bp, and 359 bp length fragments for goat, sheep, deer, buffalo, cattle, yak, pig, and camel, respectively. This primer pair had no cross-reaction with other common domestic animals and fish. The limit of detection varied from 0.01 to 0.05 ng of genomic DNA for eight animal species in a 20 µl PCR mixture. Each PCR product could be further digested into fragments with variable sizes and qualitative analysis by SspI restriction enzyme. This developed PCR-RFLP assay was sufficient to distinguish all targeted species. Compared with the previous published related methods, this approach is simple, with high throughput, fast processing rates, and more cost-effective for routine identification of meat in foodstuffs.

Sonic hedgehog protein regulates fibroblast growth factor 8 expression in metanephric explant culture from BALB/c mice: Possible mechanisms associated with renal morphogenesis

The sonic hedgehog (SHH) morphogen regulates cell differentiation and controls a number of genes during renal morphogenesis. To date, the effects of SHH on fibroblast growth factors (Fgfs) in embryonic kidney development remain unclear. In the present study, explants of BALB/c mouse embryonic kidney tissues were used to investigate the role of exogenous SHH on Fgf8 and Fgf10 expression levels ex vivo. Ureteric bud branches and epithelial metanephric derivatives were used to determine the renal morphogenesis with Dolichos biflorus agglutinin or hematoxylin‑eosin staining. mRNA expression levels were determined using reverse transcription‑quantitative polymerase chain reaction, while the protein expression levels were examined using immunohistochemistry and western blot analysis. During the initial stages of metanephric development, low levels of SHH, Fgf8, and Fgf10 expression were observed, which were found to increase significantly during more advanced stages of metanephric development. In addition, exogenous SHH protein treatment increased the number of ureteric bud branches and enhanced the formation of nephrons. Exogenous SHH reduced the Fgf8 mRNA and protein expression levels, whereas cyclopamine (an SHH‑smoothened receptor inhibitor) interfered with SHH‑mediated downregulation of Fgf8 expression. By contrast, exogenous SHH protein was not found to modulate Fgf10 mRNA and protein expression levels. In conclusion, these results indicate that the modulatory effects of SHH on BALB/c mouse metanephric explant cultures may involve the regulation of Fgf8 expression but not Fgf10 expression, which provides evidence for the functional role of Fgf proteins in renal morphogenesis.

Galectin-1, a novel ligand of neuropilin-1, activates VEGFR-2 signaling and modulates the migration of vascular endothelial cells

Galectin-1 (Gal-1), a homodimeric prototype of the galectins with a single carbohydrate-recognition domain, was recently identified as being overexpressed in tumor-associated capillary endothelial cells. The role of Gal-1 in endothelial cellular functions and the mechanism of action of Gal-1 remain unknown. Neuropilin-1 (NRP1) is a neuronal receptor that mediates repulsive growth cone guidance, and NRP1 functions in endothelial cells as a coreceptor (with vascular endothelial growth factor receptors (VEGFRs)) for VEGF(165). In this study, we found that Gal-1 was overexpressed in the tumor-associated endothelial cells of oral squamous cell carcinomas (P<0.001). Gal-1 increased the proliferation and adhesion of endothelial cells, and enhanced cell migration in combination with VEGF(165). Surprisingly, Gal-1 selectively bound NRP1 via the carbohydrate-recognition domain, but did not bind VEGFR-1, VEGFR-2 or VEGFR-3. The Gal-1-NRP1 interaction mediated the migration and adhesion of endothelial cells. The binding of Gal-1 to NRP1 enhanced VEGFR-2 phosphorylation and stimulated the activation of the mitogen activated protein (MAP) kinases SAPK1/JNK (stress activated protein kinase-1/c-Jun NH2-terminal kinase). These findings show, for the first time, that Gal-1 can directly bind to NRP1 on endothelial cells, and can promote the NRP1/VEGFR-2-mediated signaling pathway as well as NRP1-mediated biological activities.

Familial aggregation of lung cancer in a high incidence area in China

To investigate whether lung cancer clusters in families in a high incidence county of China, an analysis was conducted using data on domestic fuel history and tobacco use for family members of 740 deceased lung cancer probands and 740 controls (probands' spouses). Lung cancer prevalence was compared among first-degree relatives of probands and of controls, taking into account various factors using logistic regression and generalised estimating equations. First-degree relatives of probands, compared with those of controls, showed an excess risk of lung cancer (odds ratio (OR)=2.05, 95% confidence interval (CI): 1.68-2.53). Overall, female relatives of probands had a greater risk than did their male counterparts, and the risk was 2.90-fold for parents of probands as compared with parents of spouses. Female relatives of probands had 2.67-fold greater risk than female controls. Lung cancer risk was particularly marked among mothers (OR=3.78, 95% CI: 2.03-7.12). Having two or more affected relatives was associated with a 2.69-5.40-fold risk increase. The risk elevation was also found for other cancers overall. Results confirm previous findings of a genetic predisposition to lung cancer, and also imply that lung cancer may share a genetic background with other cancers.

Multiple colonic ulcers caused by Churg-Strauss syndrome in a 15-year-old girl

Churg-Strauss syndrome (CSS), or allergic granulomatous angiitis, is an uncommon vasculitic syndrome that is found mainly in middle-aged adults. We describe a 15-year-old girl with CSS, diagnosed by histological findings and characteristic clinical features. The patient experienced two episodes of catastrophic gastrointestinal vasculitis, resulting in resection of 150 cm of small intestine and right hemicolectomy. Colonoscopic examination showed multiple colonic ulcers with active bleeding. The clinical course of the patient was grave and refractory to the therapy of steroid and cytotoxic drugs. In the world literature only two patients with multiple colonic ulcers caused by CSS have been reported, and very rare cases of childhood-onset CSS have been published. We reviewed CSS in children and found that the prognosis was poorer than that in adults.

Effects of angiotensin converting enzyme inhibitor and angiotensin II type 1 receptor blocker on cardiac dysfunction induced by isoproterenol in dogs

We examined whether angiotensin converting enzyme (ACE) inhibitors and angiotensin II type 1 receptor blockers (ARB) prevent isoproterenol (ISO)-induced left ventricular (LV) dysfunction in dogs. The effects of a large dose of ISO, 1 microg/kg/min, 3 h infusion, were investigated in three groups with simultaneous infusion of an ACE inhibitor (quinaprilat), ARB (candesartan) or saline. ISO infusion significantly decreased LV dP/dt, LV ejection fraction and LV fractional shortening, and significantly increased tau, the time constant of isovolume relaxation of LV, and LV end diastolic pressure. All of these changes were significantly attenuated in both the ACE inhibitor and ARB groups, especially in the ARB group. Serum levels of creatinin kinase isoform MB, lactate dehydrogenase and lipid peroxide were significantly increased by ISO. However, the increases in these markers of myocardial damage were significantly diminished by simultaneous infusion of an ACE inhibitor or ARB, especially by ARB. In conclusion, an ACE inhibitor and ARB prevent LV systolic and diastolic dysfunction as well as myocardial damage induced by excess beta-adrenergic stimulation.

Effect of various surface protections on the margin microleakage of resin-modified glass ionomer cements

STATEMENT OF PROBLEM

Because conventional glass ionomer cements are moisture sensitive, a surface coating is recommended during the initial setting stage. It is unknown whether resin-modified glass ionomer cements also need surface protection.

PURPOSE

This study investigated the effect of various surface protections on microleakage with Class V resin-modified glass ionomer restorations.

MATERIAL AND METHODS

Forty extracted molars with buccal and lingual Class V cavity preparations were restored with a resin-modified glass ionomer (Fuji II LC). The occlusal margin of each restoration was on enamel and the cervical margin on dentin. After immediate finishing and polishing, the teeth were divided into 4 groups according to the following surface protection treatments: group I, unprotected; group II, Fuji varnish; group III, resin adhesive; and group IV, acid etching and resin adhesive. After these procedures, all teeth were stored in isotonic saline for 24 hours, thermocycled 1500 times at 5 degrees C to 60 degrees C, and soaked in dye solution for 24 hours. The teeth then were longitudinally sectioned and observed under a stereomicroscope. The degree of dye penetration was recorded and analyzed with the Kruskal-Wallis and Mann-Whitney tests (P<.05)

RESULTS

None of the 4 groups demonstrated complete margin sealing at either the occlusal or cervical margins. Groups II and III displayed the least microleakage at cervical margins; a significant difference existed between groups I and III (P=.034). Compared with the other 3 groups, group IV showed significantly greater microleakage at the cervical margins.

CONCLUSION

Although resin-modified glass ionomers can be finished immediately, they remain moisture sensitive. Within the limitations of this study, the results suggest that resin adhesive should be used as a surface protection to reduce margin microleakage of resin-modified glass ionomer restorations.

Prophylactic total thyroidectomy in an 8-year-old girl with multiple endocrine neoplasia type 2A

We report a genetic carrier of multiple endocrine neoplasia type 2A (MEN 2A) who underwent prophylactic total thyroidectomy. The asymptomatic carrier of MEN 2A, an 8-year-old Taiwanese girl, was admitted for early thyroidectomy. Preoperative basal plasma concentrations of calcitonin and intact parathyroid hormone, and urine vanillylmandelic acid excretion, were normal. Ultrasonography of the thyroid was also normal. Pathology did not reveal any gross lesion but C-cell hyperplasia of the thyroid gland was found microscopically. Prophylactic total thyroidectomy is encouraged and is justified during the first decade of life for MEN 2A carriers.

Microarray profiling of gene expression patterns in bladder tumor cells treated with genistein

Microarray technology was used to gain an insight into the molecular events of tumor cell growth inhibition mediated by the soy isoflavone genistein. For this, a susceptible bladder tumor line TCCSUP was treated with the inhibitory dose (50 microM) of genistein for various periods of time, followed by mRNA isolations, cDNA probe preparations, and hybridization individually to cDNA chips containing 884 sequence-verified known human genes. After analyzing the hybridization signals with a simple quantitative method developed by this study, we detected that egr-1, whose expression has been associated with proliferation and differentiation, was transiently induced and this expression pattern was later confirmed by RT-PCR. Thus, microarray technology is a reliable and powerful tool for profiling gene expression patterns in many biological systems related to cancer. We further detected many groups of genes with distinct expression profiles and most of them encode for proteins that regulate the signal transduction or the cell cycle pathways. These genes warrant further investigation as regards their roles in the susceptibility of the tumor cell line to the antitumor drug.

Follicular dendritic cell sarcoma of the colon mimicking stromal tumour

AIMS

Follicular dendritic cell tumours are very rare neoplasms that often occur in lymph nodes. We report here a case in the colon, a hitherto unreported site, in a 37-year-old female. The differentiation from gastrointestinal stromal tumour is emphasized.

METHODS AND RESULTS

The tumour was tan, elastic and solid with surface ulceration. Microscopically, it was composed of oval to spindle tumour cells with syncytial cytoplasm arranged in fascicular and whorled patterns. There were many infiltrating lymphocytes. The histological appearance resembled gastrointestinal stromal tumour, thymoma or meningioma. Distinct from the stromal tumour, the lymph node was also involved by the tumour. Immunohistochemically, the tumour cells were positive for CD21, CD35 and CD68, but negative for cytokeratin, CD34, smooth muscle actin, desmin, S100 protein, epithelial membrane antigen, leukocyte common antigen, HMB-45 and c-kit. In-situ hybridization study was negative for Epstein-Barr virus RNA sequences. Ultrastructurally, the tumour cells possessed cytoplasmic processes joined by desmosomes.

CONCLUSIONS

This entity should be considered in the list of differential diagnoses for gastrointestinal stromal tumour. The lymph node metastasis and immunohistochemical features are of value for identification of this rare neoplasm.

Dissemination of CTX-M-3 and CMY-2 beta-lactamases among clinical isolates of Escherichia coli in southern Taiwan

A total of 1,210 clinical isolates of Escherichia coli collected from a university hospital in southern Taiwan were screened for production of extended-spectrum beta-lactamases (ESBLs). Expression of classical ESBLs (resistant to extended-spectrum beta-lactam agents and susceptible to beta-lactam inhibitors) was inferred in 18 isolates by the phenotypic confirmatory test. These included 10 isolates producing CTX-M-3, 2 strains carrying SHV-12, 1 strain harboring SHV-5, 1 strain expressing TEM-10, and 4 strains producing unidentifiable ESBLs with a pI of 8.05, 8.0, or 7.4. Eighteen isolates that showed decreased susceptibilities to ceftazidime and/or cefotaxime, negative results for the confirmatory test, and high-level resistance to cefoxitin (MICs of >/=128 microg/ml) were also investigated. Five isolates were found to produce CMY-2 AmpC enzymes, one isolate carried both CTX-M-3 and CMY-2, and the remaining three and nine isolates expressed putative AmpC beta-lactamases with pIs of >9.0 and 8.9, respectively. Thus, together with the isolate producing CTX-M-3 and CMY-2, 19 (1.6%) isolates produced classical ESBLs. Pulsed-field gel electrophoresis revealed that all isolates carrying CTX-M-3 and/or CMY-2 were genetically unrelated, indicating that dissemination of resistance plasmids was responsible for the spread of these two enzymes among E. coli in this area. Among the 16 isolates expressing CTX-M-3 and/or CMY-2, 5 might have colonized outside the hospital environment. Our data indicate that CTX-M-3 and CMY-2, two beta-lactamases initially identified in Europe, have been disseminated to and are prevalent in Taiwan.

Induction of antitumor immunity with combination of HER2/neu DNA vaccine and interleukin 2 gene-modified tumor vaccine

The therapeutic effects of both cytokine-secreting tumor vaccine and DNA vaccine were studied using mouse MBT-2 bladder cancer cells as a model. Cytokine-secreting MBT-2 cells were obtained by infecting cells with retroviral particles containing interleukin (IL) 2-, IL-4-, or granulocyte-macrophage colony-stimulating factor (GM-CSF)-expression vector. The MBT-2-IL-2 cells were not tumorigenic in syngenic C3H mice at all. Tumor formation decreased significantly for the MBT-2-GM-CSF cells. MBT-2-IL-2, -IL-4, and -GM-CSF cells were killed by irradiation and tested as tumor vaccines. The irradiated MBT2-IL-2 cells could complete protect mice from the growth of the preexisting tumor cells, and the immune memory lasted for 8 months. On the other hand, irradiated MBT-2-IL-4 and MBT-2-GM-CSF cells were less effective. When the loading tumor mass increased, all tumor vaccines lost protective effects. DNA vaccine encoding the tumor antigen neu was additionally tested to improve the therapeutic efficacy. Coinjection of 60 microg pSV-neu DNA was effective in enhancing the antitumor effects of MBT2-IL-2; however, DNA vaccine alone cannot prevent the progression of the preexisting tumor. Immunohistochemical analysis of tumor infiltrate revealed massive increase of CD4+ lymphoid cells in the group of mice treated with both DNA vaccine and IL-2-secreted tumor vaccine. Western blotting demonstrated the presence of anti-neu antibody in the serum from immunized mice. In contrast, combination of DNA vaccine and MBT-2-GM-CSF has no additive effect. The results indicate the combination of DNA vaccine and IL-2-secreting tumor vaccine can additionally improve therapeutic efficacy, and the efficacy is correlated with the increase of CD4+ T lymphocytes and anti-neu antibody.

Detection of human papillomavirus in cholesteatomas

The presence of human papillomavirus DNA in cholesteatoma may have some role in the development of middle ear cholesteatoma as well as in papilloma. In the present study, polymerase chain reaction and in situ hybridization with human papillomavirus (HPV)-6 and -11 DNA probes were used to detect the presence of HPV DNA in 32 human middle ear cholesteatomas. Only one specimen contained HPV-6 DNA. Although its occurrence may have been coincidental, it is also possible that the hyperproliferative epithelium of cholesteatomas might have some relationship with HPV infections.

Epstein-Barr virus detection in neck metastases by in-situ hybridization in fine-needle aspiration cytologic studies: an aid for differentiating the primary site

BACKGROUND

Nasopharyngeal carcinoma (NPC) is strongly associated with Epstein-Barr virus (EBV). The metastasis to cervical lymph nodes represents a frequent initial manifestation of NPC. The usefulness of EBV detection by polymerase chain reaction (PCR) in the diagnosis of occult NPC with cervical metastasis has been reported. Our previous study showed that EBER1 in-situ hybridization was somewhat more sensitive and specific than PCR in detecting EBV in the evaluation of specimens from a population at high risk for NPC.

METHODS

Fine-needle aspiration cytologic specimens of neck masses from 30 patients were investigated, including 10 NPC primary tumors, 19 squamous cell carcinomas from other sites of the head and neck (9 oral cavity, 2 paranasal sinuses, 2 oropharynx, 3 larynx, and 3 hypopharynx), and 1 diffuse large-cell lymphoma. EBER1 in-situ hybridization was performed on direct smears made from aspirates.

RESULTS

EBER1 signals were detected in all neck metastases from the nasopharynx but none of the specimens from other primary sites.

CONCLUSIONS

This study suggests that EBER1 in-situ hybridization can be used as a supplemental tool for differential diagnosis whenever fine-needle aspiration cytologic examination is presented with a neck metastasis without knowing the primary site.

Expression of Tie-2, angiopoietin-1, angiopoietin-2, ephrinB2 and EphB4 in pyogenic granuloma of human gingiva implicates their roles in inflammatory angiogenesis

Tie-2, angiopoietin-1 (Ang-1), angiopoietin-2 (Ang-2), ephrin-B2 and Eph-B4 are all important vascular morphogenesis factors which exhibit their functions in angiogenesis and blood vessel remodeling in embryonic stage. However, their roles in post-natal inflammatory angiogenesis are still unclear. Pyogenic granuloma is a benign inflammatory lesion that mostly occurs on the gingiva of females with high levels of steroid hormones. Prominent capillary growth in hyperplastic granulation tissue is characteristic histopathologically in pyogenic granuloma. The purpose of this study was to detect and compare the expressions of Tie-2, Ang-1, Ang-2, ephrin-B2 and Eph-B4 among pyogenic granuloma on human gingiva, gingiva diagnosed with periodontitis and healthy gingiva by immunohistochemistry. The immunostaining revealed that all of the endothelial cells and some mesenchymal cells expressed Tie-2. The cells which expressed Ang-1 and Ang-2 were mainly macrophage- or monocyte-like mesenchymal cells and smooth muscle cells surrounding blood vessels. The expression of ephrin-B2 and Eph-B4 was not exclusively limited to the endothelial cells of arteries and veins, respectively, as in mice embryo. Eph-B4 was expressed in the endothelial cells of newly budding capillaries and venules while ephrin-B2 was expressed in macrophage-like mesenchymal cells. Some of the ephrin-B2 positive cells were in direct contact with endothelial cells. The statistical analysis demonstrated that all of the five factors were upregulated in pyogenic granuloma compared to healthy gingiva. In conclusion, the 5 polypeptides mentioned above may play important roles in the process of adult inflammatory neovascularization, especially in pyogenic granuloma. It is highly plausible that most of the new capillaries in inflammatory angiogenesis originated from venules instead of arterioles.

Comparison of the MB/BacT and BACTEC MGIT 960 system for recovery of mycobacteria from clinical specimens

A total of 543 specimens were cultured in parallel with the MB/BacT and BACTEC MGIT 960 systems and on the conventional solid media. Mycobacteria were identified from 95 (17.5%) specimens, including 63 (66.3%) Mycobacterium tuberculosis and 32 (33.7%) nontuberculous mycobacteria. The recovery rates for the MB/BacT, MGIT 960, and solid media were 91.6, 87.4, and 54.7%, respectively, for all mycobacteria; the recovery rates were 93.6, 88.9, and 63.4%, respectively, for M. tuberculosis complex alone, and 87.5, 84.4, and 37.5%, respectively, for all nontuberculous mycobacteria. The mean times to detection of all mycobacteria by individual systems were 13. 9, 8.7, 31.7 days for the MB/BacT, MGIT 960 and solid media, respectively, 13.9, 9.3, 32.9 days for M. tuberculosis alone, and 14. 1, 8.1, 27.2 days for all nontuberculous mycobacteria. The contamination rates of the MB/BacT and MGIT 960 were 10.2 and 5.4%, respectively. With regard to detection times and recovery rates, both automated systems are superior to the conventional media (all p < 0.005). As compared to the MB/BacT, the MGIT 960 detected mycobacterial growth more rapidly (p < 0.001), and had a lower contamination rate (p = 0.003); however, there was no statistically significant difference in recovery rates between these two systems. These results indicate that both MGIT 960 and MB/BacT systems are rapid, sensitive, and efficient methods for the recovery of mycobacteria from clinical specimens.

The detection and comparison of angiogenesis-associated factors in pyogenic granuloma by immunohistochemistry

BACKGROUND

Pyogenic granuloma is a benign inflammatory lesion demonstrating obvious activity of angiogenesis. Female steroid hormones are believed to play important roles in the etiology because the lesion is frequently found in females with high levels of sex hormones. Few molecular mechanisms of the pathogenesis have been proposed and proven. The purpose of this study was to detect and compare the expression of angiogenesis-associated factors among healthy gingiva, gingiva from periodontitis, and pyogenic granuloma to clarify the pathogenesis of pyogenic granuloma.

METHODS

Fifteen specimens were collected from each of 3 groups of gingiva (healthy gingiva, periodontitis, and pyogenic granuloma). The subjects were age and gender matched. The specimens were processed for immunohistochemistry to detect and compare the expression of 2 angiogenesis enhancers, i.e., vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF), 2 angiogenesis inhibitors, i.e., angiostatin and thrombospondin-1 (TSP-1), and estrogen receptor (ER). Using the subject as the unit of statistical analysis, either analysis of variance or chi-square analysis was employed to show the statistically significant difference at a level P <0.05.

RESULTS

The pyogenic granuloma group expressed significantly more VEGF and bFGF than healthy gingiva and periodontitis. The positive staining of VEGF was mostly localized in the cytoplasm of macrophages and fibroblasts while that of bFGF was in the extracellular matrix of lamina propria. Angiostatin was expressed significantly less in pyogenic granuloma than the other 2 groups and was mostly localized in the nuclei of endothelial cells and epithelial cells. There was no significant difference in the expression of TSP-1 and ER among the 3 groups.

CONCLUSIONS

The results of this research suggest that the etiology of pyogenic granuloma is due to the imbalance between angiogenesis enhancers and inhibitors. Whether and how the angiogenesis-associated factors are regulated by female steroid hormones remain to be answered.

Arcobacter butzleri bacteremia in a patient with liver cirrhosis

Invasive Arcobacter butzleri infection in humans has been rarely described. We report a 60-year-old man with liver cirrhosis who presented with high fever and esophageal variceal bleeding. Two aerobic blood cultures grew Campylobacter-like organisms. The biochemical reactions of the isolate were inconclusive, while sequence analysis of the 16S rRNA gene definitively identified the organism as A. butzleri. The patient's bleeding stopped after endoscopic sclerosing therapy. Although the organism appeared to be resistant to cephalosporins on the basis of the minimum inhibitory concentrations determined with the E test, the fever resolved with parenteral cefuroxime. Whether the clinical improvement was related to cephalosporin therapy or to the self-limited nature of Arcobacter bacteremia is not known.

Seborrheic keratosis of conjunctiva simulating a malignant melanoma: an immunocytochemical study with impression cytology

OBJECTIVE

Seborrheic keratosis on the conjunctiva appears to have never been reported in the literature. The authors report here a well-documented case of seborrheic keratosis of conjunctiva clinically simulating a malignant melanoma.

DESIGN

Case report.

METHODS

A 66-year-old man presented with a juxtalimbal pigmented tumor involving the temporal conjunctiva of his left eye. Because of the rapid enlargement of the mass within a period of 5 months, a clinical diagnosis of malignant melanoma was made. Cytopathologic examinations were performed by impression cytology before the patient underwent a wide en-block excision of the tumor.

MAIN OUTCOME MEASURES

Cytologic features were studied by impression cytology with periodic acid-Schiff-Papanicolaou stain. Immunochemical characteristics of tumor cells were studied by immunochemical stain of cytokeratin and HMB-45. Tumor morphology was observed by histopathologic examination.

RESULTS

Impression cytology disclosed basaloid cells intermixing with squamoid cells, and these cells demonstrated positive immunoreactivity to cytokeratin and no reactivity to HMB-45. Histopathologic examination of the tumor specimen established the diagnosis of seborrheic keratosis, and the results of immunohistochemical staining were consistent with those of the impression cytology with immunocytochemical staining.

CONCLUSION

The authors describe the first case report of conjunctival seborrheic keratosis and present its immunocytochemical and immunohistochemical characteristics. Such a benign lesion can clinically mimic a malignant melanoma.

Analysis of the expression of Fas-L in nasopharyngeal carcinoma tissues

Nasopharyngeal carcinoma (NPC) is an epithelial cancer with a high incidence in Southeast Asia. How it escapes attack from the host immune system is not fully understood. Recently, pieces of evidence show that Fas-ligand (Fas-L)-mediated apoptosis may be involved in immune privilege of tumours. To determine whether a similar mechanism may exist in NPC, the expression of Fas-L was analysed. Biopsy specimens of the nasopharynx were taken from 27 NPC patients. Histologically, they were either non-keratinizing or undifferentiated carcinomas. Nasopharyngeal biopsies of 11 other patients that proved to have no tumour served as control. The transcripts of Fas-L were detected by reverse transcription-polymerase chain reaction. Localization of Fas-L protein was performed with immunohistostaining using an antibody recognizing human Fas-L. All nasopharyngeal tissues have a similar amount of transcripts of Fas-L. However, the Fas-L protein was detected exclusively on the cell surface of malignant epithelial cells of NPC. The present findings suggest that Fas-L protein may be involved in evading immune attack of NPC.

Genetic alterations in oral squamous cell carcinoma of young adults

The underlying molecular abnormalities associated with head and neck squamous cell carcinoma in young adults (< 40 years) are unknown. We analyzed DNA extracted from paired microdissected samples of normal squamous epithelia and invasive oral squamous cell carcinomas from 36 young adults at microsatellite loci commonly found in older patients and correlated the results with clinicopathologic parameters and outcome. Our results showed that 30 of the 36 (83%) tumors manifest loss of heterozygosity (LOH) in at least one marker. Microsatellite instability was manifested in only six tumors (< 17%). The highest incidences of alterations were noted at markers D9S168 (9p23-22), TP53 (17p13), and D17S799 (17p11) on the short arms of chromosomes 9 and 17. In general, the incidences of LOH at 3, 9 and 17p regions in young adults were similar to those found in older patients. No correlation between LOH at chromosomes 3, 9, and 17p and clinicopathologic parameters was found. Our study indicates that chromosomal regions with frequent genetic alterations involved in young adult squamous tumorigenesis are similar to those reported in older patients. Further studies of other chromosomes in this population are underway to define the novel molecular features of these tumors.

Immunolocalization of BRCA1 protein in normal breast tissue and sporadic invasive ductal carcinomas: a correlation with other biological parameters

AIM

BRCA1, a nuclear phosphoprotein, normally functions as a negative regulator of the cell cycle and may be an active inhibitor of neoplastic progression. Mutation of the BRCA1 gene has been demonstrated in 80% of familial breast cancer. Decreased mRNA levels or aberrant subcellular locations of BRCA1 have been identified in breast cancer lines and in sporadic cases of breast cancer tissues. The expression of BRCA1 in large series of variously differentiated breast carcinomas with correlation with other biological parameters has not been clarified.

METHODS AND RESULTS

The BRCA1 expression in normal breast tissue (n = 15) and in sporadic cases of invasive ductal carcinoma (n=108) was determined using immunohistochemistry. BRCA1 expression was correlated with other prognostic parameters including p53, c-erbB-2, bcl-2, oestrogen receptor (ER), histological grade, tumour size, axillary lymph node status and age. BRCA1 was exclusively (100%) localized in the nuclei of normal ductal and lobular epithelia. However, this nuclear expression pattern was variable in breast carcinoma (76.8%). Loss of nuclear BRCA1 expression (22 of 108 cases, 20.4%) correlated well with high histological grade (P<0.025) and bcl-2-negative tumours (P<0.05) and frequently in ER-negative tumours.

CONCLUSION

BRCA1 nuclear expression could be considered to represent the normal or physiological phenotype. Complete loss of BRCA1 nuclear expression in breast cancer and its correlation with other poor prognostic markers suggest that BRCA1 expression may play an important role in the pathogenesis and prognosis of sporadic breast carcinoma. Altered BRCA1 phenotype may therefore provide an additional prognostic parameter for breast cancer.

Disseminated Mycobacterium genavense infection in a patient with acquired immunodeficiency syndrome: first case report in Taiwan

Mycobacterium genavense is a recently described fastidious mycobacterium identified as a pathogen causing disseminated infection in patients with advanced human immunodeficiency virus (HIV) disease. In this report, we describe the first reported case of disseminated M. genavense infection in a patient with acquired immunodeficiency syndrome (AIDS) in Taiwan. A 22-year-old Chinese man was found to be seropositive for HIV at age 18, in 1993. In 1997, he presented with abdominal pain, weight loss, low CD4 lymphocyte count, hepatomegaly, and generalized lymphadenopathy. Microscopic examination of a biopsy specimen from an inguinal lymph node showed both ill- and well-formed noncaseating granulomas. Numerous acid-fast bacilli were present in the histiocyte cytoplasm. Although the organism did not grow on conventional solid media used in our laboratory, two molecular biology techniques, including polymerase chain reaction (PCR) followed by sequencing of 16S rRNA, and PCR together with restriction enzyme fragment polymorphism analysis, confirmed the M. genavense infection. The patient's abdominal symptoms responded well to a chemotherapy regimen that included ethambutol, ciprofloxacin, and clarithromycin, and he survived more than 6 months after diagnosis. However, the lymphadenopathy was still present at his final follow-up. Our report indicates that disseminated infection with M. genavense should be added to the list of differential diagnoses of secondary infections in advanced AIDS patients in Taiwan.

Bone marrow metastasis in nasopharyngeal cancer: early detection using EBER1 in situ hybridization

BACKGROUND

Previous studies have reported the abundant expression of EBER1 in primary nasopharyngeal carcinoma (NPC) metastatic to lymph nodes and bone marrow (BM). This study was done to research the use of EBER1 in situ hybridization to detect micrometastasis in the marrow of NPC patients.

PATIENTS AND METHODS

A total of 41 patients who underwent BM biopsy either for routine pretherapeutic evaluation or suspected bone marrow metastasis were enrolled for study. Thirty-two patients underwent BM biopsy for routine staging examination (Group I) and 10 were examined for unexplained cytopenia, leukoerythroblastosis, disseminated intravascular coagulation, or extensive bone metastasis (Group II). The authors applied EBER1 in situ hybridization to investigate the expression of EBER1 in 42 BM specimens. Examinations were performed on paraffin embedded tissues using polymerase chain reaction-derived, digoxigenin-labeled EBER1 DNA probes.

RESULTS

Eight of 42 specimens (19%) were positive for BM metastasis. Just one (3%) had bone marrow involvement in Group I. However, seven (70%) were positive in Group II. All but one of them with bone marrow metastasis showed positive EBER1 in situ hybridization in the BM. Another patient suspected of having BM metastasis was negative for cytokeratin, but was positive for EBER1 in situ hybridization.

CONCLUSION

Routine bone marrow study is not recommended in the staging of NPC, since only 3% of patients had BM metastasis. EBER1 in situ hybridization of marrow specimens cannot detect malignant cells earlier in NPC, but can be usefully applied to cases of equivocal marrow metastasis.

EBER1 in situ hybridization as an adjuvant for diagnosis of recurrent nasopharyngeal carcinoma

The mainstay treatment of nasopharyngeal carcinoma (NPC) is radiotherapy. Although NPC is a radiosensitive tumor, 25% of NPC patients still suffered from local relapse in Taiwan. Whether the pathologic changes induced by radiation have impact on the interpretation of suspicious recurrent NPC specimens is seldom mentioned. We retrospectively analyzed 20 irradiated NPC patients who were suspected to have local recurrence and received serial nasopharyngeal biopsies. A total of 31 nasopharyngeal tissues including 15 local recurrent specimens and 16 negative specimens were entered into this study. Compared with non-irradiated nasopharyngeal tissue, the irradiated nasopharynx showed fibrosis and areas of necrosis mixed with acute or chronic inflammation. Stroma cells were enlarged, with prominent nuclei and cytoplasm, and some bizarre cells might be confused with tumor cells. These post-irradiation effects did have an impact on histological interpretation. In this study, 2 out of 16 nasopharyngeal tissues were misdiagnosed as having no recurrent tumor by using H and E stain only. However, scattered cancer cells can be clearly visualized by using EBER1 in situ hybridization. Therefore, it is recommended that EBER1 in situ hybridization is routinely used in irradiated nasopharyngeal tissues in helping the diagnosis of recurrent NPC.

EBER in situ hybridization differentiates carcinomas originating from the sinonasal region and the nasopharynx

Epstein-Barr virus (EBV) has a well-established association with nasopharyngeal carcinoma (NPC), while its association with sinonasal carcinoma is still controversial. The role of EBV in sinonasal carcinoma and the potential value of EBER is situ hybridization in differentiating carcinomas originating from these anatomically neighboring regions were investigated. EBER in situ hybridization was applied to detect EBV in the specimens of surgically proved sinonasal carcinoma and the biopsies of carcinoma of the nasopharynx. EBER in situ hybridization was performed on paraffin embedded tissues by using PCR-derived, digoxigenin-labeled EBER-1 DNA probes. EBV was detected in 2 of 31 (6.5%) surgical specimens of sinonasal carcinoma, including 1 keratinizing squamous cell carcinoma and 1 adenocarcinoma. EBV was detected in all of 31 (100%) biopsies of carcinomas of the nasopharynx, including 1 keratining squamous cell carcinoma, 15 nonkeratinizing carcinomas, 14 undifferentiated carcinomas, and 1 adenocarcinoma. The present study does not support the role of EBV in the development of sinonasal carcinoma as does in carcinoma of the nasopharynx. EBER in situ hybridization is a useful adjunct for differentiating carcinomas originating from the sinonasal region and the nasopharynx.

Application of endoscopic sinus surgery to primary atrophic rhinitis? A clinical trial

The aetiology of primary atrophic rhinitis (AR) is still unclear. Based on the sinus infection theories, endoscopic sinus surgery (ESS) was applied to treat AR. ESS was performed on 14 patients following Stammberger's techniques along with middle turbinectomy. Patients were evaluated using clinical symptoms, radiological sinus images, saccharine time tests, bacterial cultures and mucosal ultrastructures, before and 2 years after ESS. Three patients had good recoveries, 6 had partial recoveries and another 5 had persistent disease. Good recovery patients showed clear nasal cavities and mucociliary transport system normalisation. Patients possess in meagre infectious signs or crusting extending to their nasopharynx had poor outcomes. Patients with evidence of obvious infections (cloudy sinus images, mucopus presence in the sinuses and positive culture for Klebsiella ozaenae) had good recoveries following ESS. Candidate selection is critical for the success of ESS treatment in AR. Although further clinical trials are required to prove this strategy.

Role of streptococcal pyrogenic exotoxin B in the mouse model of group A streptococcal infection

Streptococcal pyrogenic exotoxin B (SPE B) is a cysteine protease produced by Streptococcus pyogenes. In this study, the differences in virulence between protease-positive clinical isolates and their protease-negative mutants were examined in a mouse model. Isogenic protease-negative mutants were constructed by homologous recombination, using integrational plasmids to disrupt the speB gene. These mutants caused less mortality and tissue damage than protease-positive strains when inoculated into BALB/c mice via air pouch, suggesting that SPE B cysteine protease plays an important role in the pathogenesis of S. pyogenes infection. Reconstitution of SPE B in the air pouches increased the mortality of mice receiving the speB mutant strain. Infiltrated cell numbers in the exudates from the air pouches of mice infected with SPE B-producing S. pyogenes were higher than those from mice infected with protease-negative mutants at 12 h. However, despite pretreatment with vinblastine to deplete neutrophils, injection of protease-positive bacteria still resulted in severe tissue injury, indicating that neutrophil infiltration may not be the major factor involved in SPE B-enhanced tissue damage. The role of SPE B was further confirmed by demonstrating that SPE B immunization of mice conferred protection from challenge with a lethal dose of protease-positive bacteria.

Epstein-Barr virus-associated nonsmall cell lung carcinoma: undifferentiated "lymphoepithelioma-like" carcinoma as a distinct entity with better prognosis

BACKGROUND

Epstein-Barr virus (EBV) infection in nonsmall cell lung carcinoma (NSCLC) has been demonstrated in some ethnic groups. The pathobiology and the role of EBV and oncoprotein expression in these tumors have not been studied extensively. In this study, the authors investigated EBV-encoded RNA-1 (EBER1) transcripts by in situ hybridization and the expression of latent membrane protein-1 (LMP-1) and bcl-2 protein by immunohistochemistry in NSCLC patients from Taiwan, where nasopharyngeal carcinoma is endemic.

METHODS

A total of 127 cases of NSCLC (43 cases of squamous cell carcinoma [SCC], 67 cases of adenocarcinoma [AD], 12 cases of large cell carcinoma [LCC], and 5 cases of lymphoepithelioma-like carcinoma [LE]) were included. A sensitive polymerase chain reaction-derived, digoxigenin-labeled DNA probe for in situ detection of EBER1 transcripts was performed for the detection of EBV. Immunohistochemistry using the avidin-biotin-immunoperoxidase method was also performed to evaluate the expression of bcl-2 and LMP-1.

RESULTS

EBER1 was detected in 11 of the 127 NSCLC cases (8.7%; 6 SCC cases and 5 LE cases). All 5 LE cases were EBV-positive, whereas only 6 of the 43 SCC cases (14%), 0 of 67 AD cases, and 12 LCC cases were EBV-positive (P < 0.05). All five LE cases showed diffuse, strong, positive staining of tumor cells; five of the six SCC cases showed diffuse but weak staining. Among the nontumor epithelial cells, there was no EBER1 staining of any of the 11 EBER1-positive cases. The mean age of the LE patients was 10 years younger than that of the patients with other histological types. All 5 LE patients were nonsmokers, whereas 3 of the 6 patients with EBER1-positive SCC (50%) were smokers. EBER1 expression did not correlate with the 2-year survival rate of overall cases, but all 5 LE patients were alive without clinical evidence of disease at last follow-up. Gender, lymph node or distant metastasis, and clinical stage were not found to have any correlation with EBER1 expression (P > 0.05). All LE cases had bcl-2 oncoprotein expression (100%). This frequency was significantly different from other histologic types (P < 0.05). The LMP-1 detection rate was low and demonstrated no correlation with bcl-2 expression.

CONCLUSIONS

In this study, the authors found that the primary LE of the lung is associated with young age, a history of not smoking, high bcl-2 immunoreactivity, and better survival rate. These characteristics demonstrate that EBV-associated LE of the lung is a unique entity. The findings of the current study suggest that EBV infection may play a different role in the tumorigenesis of primary LE of the lung than it does in other EBER1-positive NSCLCs.

Bcl-2 and proliferating cell nuclear antigen (PCNA) expression correlates with subsequent local recurrence in nasopharyngeal carcinomas

Many anticancer treatments, including radiation therapy, have been demonstrated to work through apoptosis. The treatment of choice on nasopharyngeal carcinoma (NPC), a radiosensitive tumor, is radiotherapy. Apoptosis therefore provides a good model to predict or re-evaluate the therapeutic response in NPC. Cellular genes such as p53 and bcl-2 have been shown to be involved in apoptosis. Proliferating cell nuclear antigen (PCNA) is a useful marker for proliferating cells. This study was designed to investigate whether the expression of p53, bcl-2 and PCNA, evaluated on tumor specimens obtained at diagnosis, is indicative of the subsequent local recurrence and distant metastasis following radiation therapy. We analyzed the expression of p53, bcl-2 and PCNA by immunohistochemical methods from NPC specimens prior to radiation therapy. A total of 63 T3/T4 NPC patients including 10 patients with local relapse (Group I), 19 patients with distant metastasis (Group II), and 34 disease-free patients (Group III) were assessed. Six of the 10 (60%) group I NPC, 4 of the 19 (21.1%) group II NPC, and 13 of the 34 (38.2%) group III NPC exhibited positive p53 expression. For bcl-2 immunostaining, 8 of the 10 (80%) group I NPC, 10 of the 19 (52.6%) group II NPC, and 10 of the 34 (29.4%) group III NPC were positive. High PCNA labelling index was shown in 6 of the 10 (60%) group I NPC, 7 of the 19 (36.8%) group II NPC, and 5 of the 34 (14.7%) group III NPC. The bcl-2 and PCNA reactivity in NPC developing local recurrence after radiation therapy was significantly higher than that in the disease-free NPC (p < 0.05). These findings show that the overexpression of bcl-2 and high PCNA labelling index are probably related to local relapse in NPC patients receiving radiation therapy alone as primary treatment.

Epstein-Barr virus-associated nonsmall cell lung carcinoma: undifferentiated "lymphoepithelioma-like" carcinoma as a distinct entity with better prognosis

BACKGROUND

Epstein-Barr virus (EBV) infection in nonsmall cell lung carcinoma (NSCLC) has been demonstrated in some ethnic groups. The pathobiology and the role of EBV and oncoprotein expression in these tumors have not been studied extensively. In this study, the authors investigated EBV-encoded RNA-1 (EBER1) transcripts by in situ hybridization and the expression of latent membrane protein-1 (LMP-1) and bcl-2 protein by immunohistochemistry in NSCLC patients from Taiwan, where nasopharyngeal carcinoma is endemic.

METHODS

A total of 127 cases of NSCLC (43 cases of squamous cell carcinoma [SCC], 67 cases of adenocarcinoma [AD], 12 cases of large cell carcinoma [LCC], and 5 cases of lymphoepithelioma-like carcinoma [LE]) were included. A sensitive polymerase chain reaction-derived, digoxigenin-labeled DNA probe for in situ detection of EBER1 transcripts was performed for the detection of EBV. Immunohistochemistry using the avidin-biotin-immunoperoxidase method was also performed to evaluate the expression of bcl-2 and LMP-1.

RESULTS

EBER1 was detected in 11 of the 127 NSCLC cases (8.7%; 6 SCC cases and 5 LE cases). All 5 LE cases were EBV-positive, whereas only 6 of the 43 SCC cases (14%), 0 of 67 AD cases, and 12 LCC cases were EBV-positive (P < 0.05). All five LE cases showed diffuse, strong, positive staining of tumor cells; five of the six SCC cases showed diffuse but weak staining. Among the nontumor epithelial cells, there was no EBER1 staining of any of the 11 EBER1-positive cases. The mean age of the LE patients was 10 years younger than that of the patients with other histological types. All 5 LE patients were nonsmokers, whereas 3 of the 6 patients with EBER1-positive SCC (50%) were smokers. EBER1 expression did not correlate with the 2-year survival rate of overall cases, but all 5 LE patients were alive without clinical evidence of disease at last follow-up. Gender, lymph node or distant metastasis, and clinical stage were not found to have any correlation with EBER1 expression (P > 0.05). All LE cases had bcl-2 oncoprotein expression (100%). This frequency was significantly different from other histologic types (P < 0.05). The LMP-1 detection rate was low and demonstrated no correlation with bcl-2 expression.

CONCLUSIONS

In this study, the authors found that the primary LE of the lung is associated with young age, a history of not smoking, high bcl-2 immunoreactivity, and better survival rate. These characteristics demonstrate that EBV-associated LE of the lung is a unique entity. The findings of the current study suggest that EBV infection may play a different role in the tumorigenesis of primary LE of the lung than it does in other EBER1-positive NSCLCs.

The prognostic significance of the biomarkers p21WAF1/CIP1, p53, and bcl-2 in laryngeal squamous cell carcinoma

BACKGROUND

The clinical course of laryngeal squamous cell carcinoma (LSCC) varies considerably among patients. New biologic markers are needed to facilitate the stratification of individual patients within the conventional clinicopathologic stages of LSCC.

METHODS

Eighty-three LSCCs from an equal number of patients who received at least 10 years of follow-up were investigated for p53, p21WAF1/CIP1, and bcl-2 protein expression by immunohistochemical techniques. The results were correlated with various clinicopathologic parameters, DNA content, and patient outcome by univariate and multivariate statistical analyses.

RESULTS

Stage IV disease, large tumor size (>3 cm), positive lymph node status, extranodal extension, and p53 overexpression (in > 75% of cells) correlated significantly with prognosis in univariate analysis. There was no correlation between patient outcome and age, gender, race, histologic differentiation, or expression of bcl-2 or p21WAF1/CIP1. In multivariate analysis, lymph node status and p53 overexpression were the only factors significantly associated with survival.

CONCLUSIONS

High p53 expression and positive lymph node status were independent predictors of the outcomes of patients with LSCC. These factors may assist in prognostication and better classification of patients for treatment.

Epstein-Barr virus detection in nasopharyngeal tissues of patients with suspected nasopharyngeal carcinoma

BACKGROUND

Nasopharyngeal carcinoma (NPC) is strongly associated with Epstein-Barr virus (EBV). Detection of EBV in biopsy specimens may serve as a tumor marker.

METHODS

To assess the sensitivity and specificity of the polymerase chain reaction (PCR) and in situ hybridization in the diagnosis of NPC, formalin fixed, paraffin embedded nasopharyngeal biopsies from patients in Taiwan suspected of having NPC were studied.

RESULTS

In specimens from 107 patients with NPC, EBV was detected by PCR in 97 cases (90.7%) and by EBER in situ hybridization in 105 cases (98.1%). In specimens from 61 patients without neoplasia, EBV was detected by PCR in 7 cases (11.5%) and by EBER in situ hybridization in 0 cases.

CONCLUSIONS

These results suggest that although EBV DNA may occasionally be detected in nonneoplastic nasopharyngeal tissues, cells expressing EBER are not. EBER in situ hybridization may therefore prove to be a useful adjunct in the diagnosis of NPC.

Differentiation of BCG-induced lymphadenitis from tuberculosis in lymph node biopsy specimens by molecular analyses of pncA and oxyR

Without culture, differentiation of bacille Calmette-Guérin-induced lymphadenitis (BCG-LA) from tuberculosis (TB) is sometimes difficult by histology, but is important because of different treatment schemes. The purpose of this study was to investigate the feasibility of differentiating BCG-LA from TB in lymph nodes (LNs) by molecular analyses of two recently identified genes, pncA and oxyR. In both genes, a single tuberculosis difference exists between Mycobacterium bovis and M. tuberculosis. M tuberculosis complex (MTC) DNA was first detected in nine of ten formalin-fixed, paraffin-embedded LNs from patients aged under 20 years with suspected mycobacterial infections, using polymerase chain reaction (PCR) for IS6110, an insertion sequence specific for MTC species. PCR, together with direct DNA sequencing and PCR-restriction fragment length polymorphism (RFLP) assay, was then performed to identify polymorphic nucleotide in pncA and oxyR, respectively. For comparison, 37 adult cases of tuberculous lymphadenitis were also analysed by PCR-single strand conformation polymorphism (SSCP) assay for pncA and by PCR-RFLP for oxyR. The results revealed that five of the nine IS6110-positive child cases had a G residue at nucleotide 169 in pncA, and also had a three-band pattern after digesting the amplified oxyR segment with AluI, suggesting BCG-LA. The remaining four child cases, as well as all adult cases with detectable IS6110, showed no motility shift in pncA PCR-SSCP and had the same one-band pattern as M. tuberculosis in oxyR PCR-RFLP, suggesting TB lymphadenitis. The data from molecular analyses showed a good correlation with the vaccination history and clinicopathological findings, except for one case. This study indicates that molecular assay of either oxyR or pncA could be a rapid and useful tool to distinguish BCG-LA from TB.

Lectin immunohistochemistry study of nasal inverted papilloma and associated neoplasms

BACKGROUND

We aimed to investigate the tumor biology of nasal IP and identify the biological characteristics associated with early diagnosis and malignant transformation.

MATERIALS AND METHODS

Lectins immunohistochemistry were performed on inverted papilloma (IP), and associated neoplasms. IP synchronized with polyp or squamous cell carcinoma (SCC) and IP metachronized with SCC were analyzed and correlated to clinical information.

RESULTS

Canavalia ensiformis (ConA) and Arachis hypogaea (PNA) with neuraminidase pretreatment (NA-PNA) showed similar staining in both the IP and SCC portions of the IP synchronized with SCC. The IP and polyp portions of an IP synchronized polyp had positive NA-PNA staining, while papilloma and polyps alone had negative staining. Strong NA-PNA staining in the IP (transformed to SCC) showed significant differences from IP.

CONCLUSION

These biological characteristics define IP as a premalignant neoplasm. NA-PNA staining may be helpful for an early detection of IP. Strong NA-PNA staining in IP may predict malignant transformation.

Papillary cystic tumors of the pancreas: assessment of malignant potential by analysis of progesterone receptor, flow cytometry, and ras oncogene mutation

BACKGROUND

Although the biologic behavior of papillary cystic tumor (PCT) of the pancreas is more favorable than the adenocarcinoma, a malignant form has been reported. There has been much controversy as to the histologic evidence for malignancy. The purpose of this study is to evaluate whether the ras oncogene mutation is present in the PCT, together with hormone receptor status and DNA flow cytometry that can be used to predict tumor aggressiveness.

MATERIALS AND METHODS

In 6 collected cases of PCT, estrogen receptors (ER) and progesterone receptors (PR) were detected by immunohistochemical techniques, DNA ploidy and S-phase fraction (SPF) were studied by flow cytometry, and H, K, and N-ras oncogene mutation were analyzed by polymerase chain reaction (PCR).

RESULTS

General strong positive immunostaining of PR and negative staining of ER are found in all 6 cases of PCT, including 5 adolescent girls and one 55-year-old women with areas of anaplastic transformation. Flow cytometry analysis revealed diploid DNA in all 6 cases but higher SPF in the anaplastic portion of the old one. None of the 6 cases showed H-, K-, or N-ras oncogene mutation.

CONCLUSIONS

These results suggest PR status and ras oncogene mutation appear to be not useful in predicting aggressive behavior. DNA ploidy and S-phase fraction may provide useful information for prognosis, but their more precise prognostic value of PCT needs a larger number of cases to clarify.