First-principle calculations of the structural, vibrational, mechanical, electronic, and optical properties of ε-O8 under pressure

The vibrational, mechanical, electronic, and optical properties of the ε-O₈ phase in the pressure range of 11.4-70 GPa were studied by the first-principle calculation method. The phonon dispersion curves have a tiny virtual frequency at 60 GPa, which indicates that ε-O₈ is dynamically unstable at 60 GPa. However, the 3-BM EOS demonstrates that the unit cell is stable up to 70 GPa. It has been shown that ε-O₈ remains ductile within the whole applied pressure range. Concurrently, we calculated the variation of the band gap of ε-O₈ in the pressure range of 11.4-70 GPa. The results show that the band gap of ε-O₈ decreases with increasing pressure. Notably, the band gap disappears within the range of 50-60 GPa, which reveals that the metallic phase transition occurs within this pressure range.

LncRNA DLGAP1-AS2 promotes the radioresistance of rectal cancer stem cells by upregulating CD151 expression via E2F1

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DLGAP1-AS2 knockdown inhibits radioresistance of rectal cancer stem cells.

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DLGAP1-AS2 elevates CD151 expression via interactions with E2F1.

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DLGAP1-AS2 facilitates radioresistance of rectal cancer by interacting with E2F1 to upregulate CD151 expression.

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DLGAP1-AS2 promotes radioresistance of rectal cancer via modulating E2F1 to elevate CD151 expression through activating AKT/mTOR/cyclinD1 signaling.

Background

Radiotherapy resistance is one of the major causes of rectal cancer treatment failure. LncRNA DLGAP1-AS2 participates in the progression of several cancers. We explored the role and potential mechanism of DLGAP1-AS2 in the radioresistance of rectal cancer stem cells.

Methods

HR8348-R cells, radioresistant cells from HR8348 after irradiation, were isolated into CD133 negative (CD133⁻) and positive (CD133⁺) cells. Cell proliferation, apoptosis, migration and tumorsphere formation were determined by CCK-8, flow cytometry, wound healing assay and tumorsphere formation assay, respectively. CD133, tumor stem cell drug resistance gene (MDR1 and BCRP1), DNA repair marker (γ-H2AX) and AKT/mTOR/cyclinD1 signaling were measured by Western blot. The relationship between DLGAP1-AS2 and E2F1 was verified using RIP. The interaction between E2F1 and CD151 promoter was confirmed using dual-luciferase reporter gene assay and ChIP. AKT inhibitor API-2 was employed for validating the effect of AKT/mTOR/cyclinD1 signaling in the radioresistance of rectal cancer cells.

Results

The DLGAP1-AS2 level was increased in CD133⁺ cells after irradiation. DLGAP1-AS2 knockdown inhibited the proliferation, migration and tumorsphere formation while stimulating apoptosis in CD133⁺ cells. DLGAP1-AS2 inhibition downregulated the expression of CD133, MDR1, BCRP1 and γ-H2AX and suppressed AKT/mTOR/cyclinD1 activation. DLGAP1-AS2 upregulated the expression of CD151 by interacting with E2F1. API-2 neutralized the promotive effects of overexpressed CD151 on radioresistance.

Conclusion

DLGAP1-AS2 accelerates the radioresistance of rectal cancer cells through interactions with E2F1 to upregulate CD151 expression via the activation of the AKT/mTOR/cyclinD1 pathway.

Genome-wide map of N6-methyladenosine circular RNAs identified in mice model of severe acute pancreatitis

BACKGROUND

Severe acute pancreatitis (SAP) is a deadly inflammatory disease with complex pathogenesis and lack of effective therapeutic options. N⁶-methyladenosine (m⁶A) modification of circRNAs plays important roles in physiological and pathological processes. However, the roles of m⁶A circRNA in the pathological process of SAP remains unknown.

AIM

To identify transcriptome-wide map of m⁶A circRNAs and to determine their biological significance and potential mechanisms in SAP.

METHODS

The SAP in C57BL/6 mice was induced using 4% sodium taurocholate salt. The transcriptome-wide map of m⁶A circRNAs was identified by m⁶A-modified RNA immunoprecipitation sequencing. The biological significance of circRNAs with differentially expressed m⁶A peaks was evaluated through gene ontology and Kyoto Encyclopedia of Genes and Genomes analysis. The underlying mechanism of m⁶A circRNAs in SAP was analyzed by constructing of m⁶A circRNA-microRNA networks. The expression of demethylases was determined by quantitative polymerase chain reaction and western blot to deduce the possible mechanism of reversible m⁶A process in SAP.

RESULTS

Fifty-seven circRNAs with differentially expressed m⁶A peaks were identified by m⁶A-modified RNA immunoprecipitation sequencing, of which 32 were upregulated and 25 downregulated. Functional analysis of these m⁶A circRNAs in SAP found some important pathways involved in the pathogenesis of SAP, such as regulation of autophagy and protein digestion. In m⁶A circRNA–miRNA networks, several important miRNAs participated in the occurrence and progression of SAP were found to bind to these m⁶A circRNAs, such as miR-24-3p, miR-26a, miR-92b, miR-216b, miR-324-5p and miR-762. Notably, the total m⁶A level of circRNAs was reduced, while the demethylase alkylation repair homolog 5 was upregulated in SAP.

CONCLUSION

m⁶A modification of circRNAs may be involved in the pathogenesis of SAP. Our findings may provide novel insights to explore the possible pathogenetic mechanism of SAP and seek new potential therapeutic targets for SAP.

[Advice on the rationalized layout of outpatient clinics in a wound repair department]

According to a document issued by the General Office of National Health Commission, "one person, one diagnosis, and one room" is required in the process of outpatient consultation. However, the patient will need to go to another room for dressing change after the doctor checks the wound if sticking to the conventional layout of current wound repair specialist outpatient clinic in hospitals and following the regulation of "separation of diagnosis and treatment". To allow a patient walking back and forth with the exposed wounds to different clinics or going to another clinic for dressing change with the original dressing reapplied to the wound is against the regulation of nosocomial infection control and the principle of sterility. To ensure that the layout of the outpatient clinic in the wound repair outpatient department not only conforms to the principle of "one person, one diagnosis, and one room", but also meets the characteristics of the diagnosis and treatment process of chronic wounds, this paper proposes the layout of "large space and small partition" in the wound repair clinic.

Non-alcoholic fatty liver disease increases the prevalence of maintenance haemodialysis in patients with chronic kidney disease

AIM

To investigate the association between non-alcoholic fatty liver disease (NAFLD) and incidence of maintenance haemodialysis in patients with chronic kidney disease (CKD).

METHODS

We enrolled patients diagnosed with CKD between 2001 and 2007. The patients were categorized into two groups based on abdominal ultrasound finding, namely those with NAFLD and those without NAFLD. The disease (maintenance haemodialysis)-free survival rate was estimated using the Kaplan-Meier method. Univariate and multivariate Cox regression analyses was used to evaluate the hazard ratios of covariates for the incidence of maintenance haemodialysis.

RESULTS

A total of 161 patients (61 with NAFLD and 100 without NAFLD) were enrolled. The mean age was 69.3 years. The mean follow-up was 7.4 years. The patients with NAFLD had an increased incidence of maintenance haemodialysis (39.3 % vs 24.0 %; p=0.0396) and inferior disease-free survival rate (p=0.006). Furthermore, diabetes (p=0.0126) and proteinuria (p=0.0003) were identified as significant predictors of CKD progression.

CONCLUSION

NAFLD was associated with an increased incidence of maintenance haemodialysis and inferior disease-free survival rate. NAFLD may impair renal function and patients with renal impairment should be monitored carefully (Tab. 3, Fig. 1, Ref. 25) Keywords: non-alcoholic fatty liver disease, haemodialysis, chronic kidney disease, proteinuria.

Bright and fast-response perovskite light-emitting diodes with an ICBA:modified-C60 nanocomposite electrical confinement layer

Bright and fast-response CH₃NH₃PbBr₃ perovskite light-emitting diodes (PeLEDs) are realized by using ICBA:modified C₆₀ (MC₆₀) nanocomposites as the hole blocking layer (HBL) and electron transport layer (ETL). The photoluminescence spectrum shows that the use of hydrophilic MC₆₀ in the ETL helps the surface passivation of the perovskite layer. In addition, the photoelectron spectra and water-droplet contact angle images show that the use of the ICBA:MC₆₀ nanocomposite ETL can simultaneously confine the electrons and holes in the perovskite layer, which boosts the injected electron-hole radiative recombination efficiency and thereby increases the electroluminescence from 1 cd m^-2 to 2080 cd m^-2 at 6 V when the ICBA:3,5OEC₆₀ nanocomposite ETL is used. In addition, the operational frequency of the optimal PeLED is up to 1.5 MHz.

Enhancement of photocurrent extraction and electron injection in dual-functional CH3NH3PbBr3 perovskite-based optoelectronic devices via interfacial engineering

Photocurrent extraction and electron injection in CH₃NH₃PbBr₃ (MAPbBr₃) perovskite-based optoelectronic devices are both significantly increased by improving the contact at the PCBM/MAPbBr₃ interface with an extended solvent annealing (ESA) process. Photoluminescence quenching and x-ray diffraction experiments show that the ESA not only improves the contact at the PCBM/MAPbBr₃ interface but also increases the crystallinity of the MAPbBr₃ thin films. The optimized dual-functional PCBM-MAPbBr₃ heterojunction based optoelectronic device has a high power conversion efficiency of 4.08% and a bright visible luminescence of 1509 cd m^-2. In addition, the modulation speed of the MAPbBr₃ based light-emitting diodes is larger than 14 MHz, which indicates that the defect density in the MAPbBr₃ thin film can be effectively reduced by using the ESA process.

Monetary Reward and Punishment to Response Inhibition Modulate Activation and Synchronization Within the Inhibitory Brain Network

A reward or punishment can modulate motivation and emotions, which in turn affect cognitive processing. The present simultaneous functional magnetic resonance imaging-electroencephalography study examines neural mechanisms of response inhibition under the influence of a monetary reward or punishment by implementing a modified stop-signal task in a virtual battlefield scenario. The participants were instructed to play as snipers who open fire at a terrorist target but withhold shooting in the presence of a hostage. The participants performed the task under three different feedback conditions in counterbalanced order: a reward condition where each successfully withheld response added a bonus (i.e., positive feedback) to the startup credit, a punishment condition where each failure in stopping deduced a penalty (i.e., negative feedback), and a no-feedback condition where response outcome had no consequences and served as a control setting. Behaviorally both reward and punishment conditions led to significantly down-regulated inhibitory function in terms of the critical stop-signal delay. As for the neuroimaging results, increased activities were found for the no-feedback condition in regions previously reported to be associated with response inhibition, including the right inferior frontal gyrus and the pre-supplementary motor area. Moreover, higher activation of the lingual gyrus, posterior cingulate gyrus (PCG) and inferior parietal lobule were found in the reward condition, while stronger activation of the precuneus gyrus was found in the punishment condition. The positive feedback was also associated with stronger changes of delta, theta, and alpha synchronization in the PCG than were the negative or no-feedback conditions. These findings depicted the intertwining relationship between response inhibition and motivation networks.

[Exploration of Recent Mobile Technologies Applied in Nursing Education]

The development of science and technology has fundamentally changed people's lives and the way that medical systems function. Increasingly, mobile technologies are being introduced and integrated into classroom teaching and clinical applications, resulting in healthcare providers introducing innovative applications into health education. These applications enhance the clinical, education, and research expertise of medical staffs and nurses, while improving quality of care and providing new experiences for patients. In order to understand the current situation and trends in nursing education, the present study adopted literature analysis to explore the influence and effect of mobile technologies that have been introduced into nursing education from the school and clinical environments. The results found that students hold positive attitudes toward introducing these technologies into their curricula. Although these technologies may increase the work efficiency of nurses in the workplace, questions remain user perceptions and professional expression. Therefore, securing patient agreement and healthcare system approval were major turning points in the introduction of mobile technologies into nursing education. In the future, adapting mobile technologies for use in teaching materials and courses may be further developed. Moreover, empirical studies may be used in future research in order to facilitate the increasingly successful integration of relevant technologies into nursing education.

Effects of mutant TDP-43 on the Nrf2/ARE pathway and protein expression of MafK and JDP2 in NSC-34 cells

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease that affects motor neurons and lacks an effective treatment. The disease pathogenesis has not been clarified at present. Pathological transactive response DNA-binding protein 43 (TDP-43) plays an important role in the pathogenesis of ALS. Nuclear translocation of nuclear factor erythroid 2 (NF-E2)-related factor 2 (Nrf2) is found in a mutant TDP-43 transgenic cell model, but its downstream antioxidant enzyme expression is decreased. To elucidate the specific mechanism of Nrf2/ARE (antioxidant responsive element) signaling dysfunction, we constructed an ALS cell model with human mutant TDP-43 using the NSC-34 cell line to evaluate the impact of the TDP-43 mutation on the Nrf2/ARE pathway. We found the nuclear translocation of Nrf2, but the expression of total Nrf2, cytoplasmic Nrf2, and downstream phase II detoxifying enzyme (NQO1) was decreased in NSC-34 cells transfected with the TDP-43-M337V plasmid. Besides, TDP-43-M337V plasmid-transfected NSC-34 cells were rounded with reduced neurites, shortened axons, increased levels of intracellular lipid peroxidation products, and decreased viability, which suggests that the TDP-43-M337V plasmid weakened the antioxidant capacity of NSC-34 cells and increased their susceptibility to oxidative damage. We further showed that expression of the MafK protein and the Jun dimerization protein 2 (JDP2) was reduced in TDP-43-M337V plasmid-transfected NSC-34 cells, which might cause accumulation of Nrf2 in nuclei but a decrease in NQO1 expression. Taken together, our results confirmed that TDP-43-M337V impaired the Nrf2/ARE pathway by reducing the expression of MafK and JDP2 proteins, and provided information for further research on the molecular mechanisms of TDP-43-M337V in ALS.

Modified nanoprecipitation method for polysulfone nanoparticles preparation

Towards developing a more universal and productive nanoprecipitation processes, we focus on the preparation of polysulfone (PSF) nanoparticles through instantaneous solvent displacement in a metal membrane contactor between dimethylformamide (DMF) and water. In the original nanoprecipitation process, cubic nuclei can form instantaneously, but slow growth and aggregation have intensive interactions. Moreover, the reservation of DMF may enhance the adhesive effect between polymeric particles, causing severe particle aggregation. To overcome this difficulty, a modified nanoprecipitation method appending a quenching step was proposed. The well-dispersed PSF nanoparticles are successfully obtained when ethyl acetate is introduced. In this way, DMF can be extracted from water solution, thus facilitating the precipitating of PSF. Furthermore, selecting water as the continuous fluid, the particle size can be adjusted simply by tuning the operating parameters, including the PSF concentration in the dispersed fluid and the ratio of two feeds. Compared with previous reports on the continuous nanoprecipitation process for polymeric nanoparticles preparation, this work shows advantages including expanding the adaptability to more functional polymers, providing better flexibility on process or product development independent of the use of surfactant, and presenting a high throughput and easy-to-scale-up equipment platform.

Retinoblastoma protein-interacting zinc-finger gene 1 (RIZ1) dysregulation in human malignant meningiomas

Retinoblastoma protein-interacting zinc-finger gene 1 (RIZ1) expression is often silenced in many types of human tumors. However, the relationship between RIZ1 expression and malignant meningiomas remains unclear. Here we have found for the first time that the expression of RIZ1 genes are associated with meningiomas progression through extensive analyses of Affymetrix GeneChip microarray data. Further validation methods for gene expression included quantitative PCR (qPCR), western blot and immunohistochemistry analysis, and these methods confirmed that RIZ1 is significantly downregulated in malignant meningioma tissues, as compared with benign meningiomas. In addition, malignant meningioma cells were stably transfected with ectogenic RIZ1 using Lentivirus-mediated transfection, and the transfections were followed by an in vitro 5-bromo-2-deoxyuridin incorporation assay, colony formation assay, cell cycle analysis, invasive analysis, apoptotic assay and western blot analysis. Our results demonstrate that the forced expression of RIZ1 in a malignant meningioma cell line inhibited cellular proliferation and arrested the cells in the G2/M phase of the cell cycle. We also confirmed that overexpression of RIZ1 may induce apoptosis of malignant meningioma cells. Furthermore, RIZ1 overexpression in malignant meningioma cells was associated with the downregulation of c-myc expression. These results from our study indicate that RIZ1 expression is significantly downregulated as the formation of meningiomas progressed, and suggest that RIZ1 may represent a promising candidate tumor suppressor gene that contributes to malignant meningiomas.

Solitary Intracranial Plasmacytoma Located in the Spheno-Clival Region Mimicking Chordoma: A Case Report

Solitary intracranial plasmacytoma (SIP) is very rare. This case report presents serial findings of SIP located in the spheno-clival region in a 54-year old female who presented with an inferior hemianopia in the right eye and an enlarged physiological blind spot in both eyes. Based on the initial diagnosis of a spheno-clival region chordoma, the tumour was partially resected by the nasal–sphenoidal sinus approach. Subsequently, the correct diagnosis of SIP was made based on the pathology and immunohistochemical staining of the tumour. The patient was treated using a whole skull-base radiation therapy protocol with 45 Gy and she was in good physical condition during the subsequent 22 months. The findings of a series of similar case reports documenting SIP in 20 cases published from 1976 to 2008 are also reviewed. Based on these case reports, the key features of SIP, including their clinical manifestations, clinical imaging characteristics, treatment and prognosis, are described.

Tailoring of silver wires and their performance as transparent conductive coatings

A feasible way to manipulate the scales of Ag wires through the polyol process is presented. By adjusting the amounts of either Pd or Ag precursor used in this process, we demonstrated the ability to control the scale of the wires. The presence of Pd ultrafine particles reduced by EG in advance served as the nuclei for inducing the subsequent formation of Ag wires, and the diameter of the resulting wires was observed to be inversely proportional to the quantity of Pd added. Further, the wire length was demonstrated to be proportional to and highly correlated with the total amount of Ag added, by a linear relationship. A glass plate coated with Ag wire film by the spray method is shown to be both transparent and conductive. The effect of scaling the wires on their performance is also discussed.

Rosette-forming glioneuronal tumour of the fourth ventricle with previous intratumoural haemorrhage: case report and review of the literature

The case is reported of a rosette-forming glioneuronal tumour of the fourth ventricle (RGTFV) in a 27-year-old male. Symptoms included headache, severe vomiting and clumsy walking that had progressively worsened over 14 days. Computed tomography and magnetic resonance imaging indicated a 3.0 x 2.5 x 2.0 cm solid-cystic mass in the fourth ventricle and obstructive hydrocephalus. The tumour showed evidence of previous intra-tumour haemorrhage, with heterogeneous enhancement after contrast administration. Complete excision of the lesion was performed. Signs of previous intra-tumoural haemorrhage were seen intra-operatively. The detailed clinical, radiological and pathological features in this patient are described and compared with existing literature on this type of tumour. Despite benign histological features and a reported favourable post-operative course, there is still limited clinical experience with this type of tumour, however intratumoural haemorrhage may result in morbidity and mortality. This report will help provide better characterization of this entity, improving the diagnosis and potentially reducing mortality in RGTFV.

A method of layer-by-layer gold nanoparticle hybridization in a quartz crystal microbalance DNA sensing system used to detect dengue virus

Dengue virus (DENV) is nowadays the most important arthropod-spread virus affecting humans existing in more than 100 countries worldwide. A rapid and sensitive detection method for the early diagnosis of infectious dengue virus urgently needs to be developed. In the present study, a circulating-flow quartz crystal microbalance (QCM) biosensing method combining oligonucleotide-functionalized gold nanoparticles (i.e. AuNP probes) used to detect DENV has been established. In the DNA-QCM method, two kinds of specific AuNP probes were linked by the target sequences onto the QCM chip to amplify the detection signal, i.e. oscillatory frequency change (DeltaF) of the QCM sensor. The target sequences amplified from the DENV genome act as a bridge for the layer-by-layer AuNP probes' hybridization in the method. Besides being amplifiers of the detection signal, the specific AuNP probes used in the DNA-QCM method also play the role of verifiers to specifically recognize their target sequences in the detection. The effect of four AuNP sizes on the layer-by-layer hybridization has been evaluated and it is found that 13 nm AuNPs collocated with 13 nm AuNPs showed the best hybridization efficiency. According to the nanoparticle application, the DNA-QCM biosensing method was able to detect dengue viral RNA in virus-contaminated serum as plaque titers being 2 PFU ml(-1) and a linear correlation (R(2) = 0.987) of DeltaF versus virus titration from 2 x 10(0) to 2 x 10(6) PFU ml(-1) was found. The sensitivity and specificity of the present DNA-QCM method with nanoparticle technology showed it to be comparable to the fluorescent real-time PCR methods. Moreover, the method described herein was shown to not require expensive equipment, was label-free and highly sensitive.

Determination of dynamic interfacial tension and its effect on droplet formation in the T-shaped microdispersion process

Interfacial tension is an important physical property affecting the droplet formation process in microfluidic devices. This work presents the variation of dynamic interfacial tension caused by slow adsorption of surfactant, as well as its influence on the liquid/liquid microdispersion process in a T-shaped microchannel. Using hexane/water-Tween 20 as the working system, it was observed that the droplet size changed with the variation of surfactant concentration when the concentration of Tween 20 was lower than 10 mmol/L, but hardly changed at higher concentrations, which was caused by the unsaturated adsorption and saturated adsorption of surfactant, respectively. The saturated interfacial tension was measured with an interfacial tension meter, and the relationship between the interfacial tension and the droplet diameter was established. Accordingly, the dynamic interfacial tension with unsaturated adsorption of surfactant was determined. The main factors affecting the dynamic interfacial tension were discussed, and a semiempirical equation was established to characterize those effects.

Safrole-Induced Ca2+Mobilization and Cytotoxicity in Human PC3 Prostate Cancer Cells

The effect of the carcinogen safrole on intracellular Ca2+ mobilization and on viability of human PC3 prostate cancer cells was examined. Cytosolic free Ca2+ levels ([Ca2+]i) were measured by using fura-2 as a probe. Safrole at concentrations above 10 microM increased [Ca2+]i in a concentration-dependent manner with an EC50 value of 350 microM. The Ca2+ signal was reduced by more than half after removing extracellular Ca2+ but was unaffected by nifedipine, nicardipine, nimodipine, diltiazem, or verapamil. In Ca2+-free medium, after treatment with 650 microM safrole, 1 microM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor) failed to release Ca2+. Neither inhibition of phospholipase C with U73122 nor modulation of protein kinase C activity affected safrole-induced Ca2+ release. Overnight incubation with 0.65-65 microM safrole did not affect cell viability, but incubation with 325-625 microM safrole decreased viability. Collectively, the data suggest that in PC3 cells, safrole induced a [Ca2+]i increase by causing Ca2+ release from the endoplasmic reticulum in a phospholipase C- and protein kinase C-independent fashion, and by inducing Ca2+ influx. Safrole can decrease cell viability in a concentration-dependent manner.

Melittin-induced [Ca2+]i increases and subsequent death in canine renal tubular cells

The effect of melittin on cytosolic free Ca2+ concentration ([Ca2+]i) and viability is largely unknown. This study examined whether melittin alters Ca2+ levels and causes Ca2+-dependent cell death in Madin-Darby canine kidney (MDCK) cells. [Ca2+]i and cell death were measured using the fluorescent dyes fura-2 and WST-1 respectively. Melittin at concentrations above 0.5 μM increased [Ca2+]i in a concentration-dependent manner. The Ca2+ signal was reduced by 75% by removing extracellular Ca2+. The melittin-induced Ca2+ influx was also implicated by melittin-caused Mn2+ influx. After pretreatment with 1 μM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor), melittin-induced Ca2+ release was inhibited; and conversely, melittin pretreatment abolished thapsigargin-induced Ca2+ release. At concentrations of 0.5–20 μM, melittin killed cells in a concentration-dependent manner. The cytotoxic effect of 0.5 μM melittin was nearly completely reversed by prechelating cytosolic Ca2+ with BAPTA. Melittin at 0.5–2 μM caused apoptosis as assessed by flow cytometry of propidium iodide staining. Collectively, in MDCK cells, melittin induced a [Ca2+]i rise by causing Ca2+ release from endoplasmic reticulum and Ca2+ influx from extracellular space. Furthermore, melittin can cause Ca2+-dependent cytotoxicity in a concentration-dependent manner.

Disposable amperometric immunosensing strips fabricated by Au nanoparticles-modified screen-printed carbon electrodes for the detection of foodborne pathogen Escherichia coli O157:H7

A disposable amperometric immunosensing strip was fabricated for rapid detection of Escherichia coli O157:H7. The method uses an indirect sandwich enzyme-linked immunoassay with double antibodies. Screen-printed carbon electrodes (SPCEs) were framed by commercial silver and carbon inks. For electrochemical characterization the carbon electrodes were coupled with the first E. coli O157:H7-specific antibody, E. coli O157:H7 intact cells and the second E. coli O157:H7-specific antibody conjugated with horseradish peroxidase (HRP). Hydrogen peroxide and ferrocenedicarboxylic acid (FeDC) were used as the substrate for HRP and mediator, respectively, at a potential +300 mV vs. counter/reference electrode. The response current (RC) of the immunosensing strips could be amplified significantly by 13-nm diameter Au nanoparticles (AuNPs) attached to the working electrode. The results show that the combined effects of AuNPs and FeDC enhanced RC by 13.1-fold. The SPCE immunosensing strips were used to detect E. coli O157:H7 specifically. Concentrations of E. coli O157:H7 from 10(2) to 10(7)CFU/ml could be detected. The detection limit was approximately 6CFU/strip in PBS buffer and 50CFU/strip in milk. The SPCE modified with AuNPs and FeDC has the potential for further applications and provides the basis for incorporating the method into an integrated system for rapid pathogen detection.

Dentatorubropallidoluysian atrophy in Chinese

BACKGROUND

Dentatorubropallidoluysian atrophy (DRPLA) is a rare, autosomal dominant neurodegenerative disease characterized by a range of clinical manifestations, including cerebellar ataxia, epilepsy, myoclonus, choreoathetosis, and dementia. Outside the Japanese population, the prevalence is extremely low worldwide. The reason for different ethnic prevalences of DRPLA is unclear. A previous assumption was that large normal alleles contribute to generation of expanded alleles and the relative frequencies of DRPLA.

OBJECTIVES

To describe the clinical, radiological, and genetic features of the first reported Chinese family with DRPLA, to our knowledge, and to compare the size distribution of normal alleles at the DRPLA locus in healthy Chinese individuals with that of other ethnic groups.

PATIENTS AND METHODS

Of 80 Chinese kindreds with autosomally dominant spinocerebellar ataxias, 1 pedigree with 2 affected patients was found by polymerase chain reaction to carry the characteristic DRPLA mutation. The allele frequencies of different CAG repeat lengths at the DRPLA locus in 225 healthy Chinese individuals were also analyzed and compared with Japanese, white, and African American distributions.

RESULTS

The clinical presentations of the 2 Chinese patients affected with DRPLA are similar to those described in Japanese patients, except that the affected father exhibited myoclonus but not chorea. Although the normal DRPLA allele size is distributed similarly in Chinese and Japanese populations, DRPLA in Chinese individuals is rare. Thus far, to our knowledge, only 1 intermediate-sized allele containing more than 30 CAG repeats has been reported among healthy Chinese individuals, in contrast to 3 among Japanese populations.

CONCLUSION

The ethnic prevalence of DRPLA seems to be correlated with the prevalence of intermediate-sized alleles in individual populations.

Mechanism of hearing loss in irradiated ears: a long-term longitudinal study

A 10-year longitudinal follow-up study of hearing was conducted in patients with nasopharyngeal carcinoma (NPC) in order to elucidate the mechanism of hearing loss in irradiated ears. Ten NPC patients were subjected to a battery of audiological tests before irradiation and 6 months, 5 years, and 10 years after irradiation. The tests included pure tone audiometry, tympanometry, eustachian tube function testing, and myringotomy to confirm middle ear effusion. The prevalences of otitis media with effusion (OME) were 25%, 25%, 40%, and 25% at the 4 testing periods described above, respectively. The prevalences of chronic otitis media were 0%, 0%, 15%, and 25%, respectively. In myringotomized ears (n = 17), the mean hearing levels for both air conduction and bone conduction were preserved from the preirradiation period to 10 years after irradiation. In contrast, in grommeted ears (n = 3), the mean hearing levels for both air conduction and bone conduction deteriorated progressively from the preirradiation period to 10 years after irradiation. We conclude that hearing can be preserved in NPC patients 10 years after irradiation if middle ear inflammation is well controlled. We do not recommend grommet insertion in irradiated NPC patients with OME, as it may result in persistent otorrhea and hearing deterioration.

Effects of surface treatments on bond strength of glass-infiltrated ceramic

The purpose of this study was to evaluate the effects of various surface treatments on the bond strength at the In-Ceram/resin composite interface. Ninety-eight In-Ceram specimens were divided into seven groups and exposed to various surface treatments as follows: (A) control (B) saliva contamination (C) saliva contamination plus aluminum oxide sandblasting (D) glove powder contamination (E) glove powder contamination plus aluminum oxide sandblasting (F) rough aluminum oxide sandblasting and (G) excess glass infiltration. A resin composite cylinder was cemented to each In-Ceram specimen with Panavia 21 resin luting cement. Half of the cemented specimens in each group were stored in water for 24 h, and the other half were stored in water for 2 weeks and then were thermo-cycled for 2000 cycles. Shear bond strengths (SBS) of seven specimens in each subgroup were determined and analysed using analysis of variance (ANOVA) and Tukey HSD test as well as Student's t-test. Scanning electronic microscopy was used to identify the type of bond failure. Shear bond strength was significantly decreased by saliva and glove powder contaminations (P < 0.05). Sandblasting treatment did not improve the saliva-contaminated specimens. However, the glove powder plus sandblasting group showed no significant difference in SBS compared with the control group. There was no significant difference in SBS between the excess glass-infiltrating group and the control group. The SBS was significantly decreased by rough aluminum oxide sandblasting (P < 0.05). The SBS values of groups without thermocycling were significantly greater than those of groups with thermocycling (P < 0.05). There were no significant differences among SBS values of the seven groups with thermocycling. Combined cohesive and adhesive bond failures were seen in every group. Various surface treatments or contaminants may significantly influence the bond strength of In-Ceram restorative in clinical use.

Lipoma arborescens of the knee: a case report

Lipoma arborescens is a rare intraarticular lesion of unknown etiology. We describe the radiographic, computerized tomographic, and magnetic resonance (MR) imaging characteristics of lipoma arborescens in a 17-year-old boy presenting with chronic painful swollen knee. Histologic examination after surgical synovectomy confirmed the diagnosis of lipoma arborescens. The fatty nature and frond-like appearance of this lesion can be demonstrated on imaging studies, especially MR imaging. Open synovectomy is curative in most cases. Although lipoma arborescens is rare, it is important to recognize and differentiate it from other synovial lesions by MR imaging.

Care of patients with chronic mental illness: comparison of home and half-way house care

Community-based services are being developed as mental health services. The purpose of this study was to examine the effect between home care and half-way house services on patients with schizophrenia. The design was quasi-experimental and used repeated measurements. There were 60 subjects, 37 receiving home care and 23 receiving half-way house care which were affiliated with one general hospital in the south of Taiwan. Of the 60 chronic schizophrenic patients, there were 34 males and 26 females with an average age of 34 years. The Quality of Life Scale was applied to measure each patient four times, at an interval of two months. These follow-up data were analyzed by Generalized Estimating Equation-I (GEE-I) because repeated observations on an individual may be correlated. The result showed that the total QOL in patients receiving home care programs was significantly higher than those receiving half-way house service. The total scores of QOL in patients under half-way house and home care services did not show secular change. The patients under home care program showed a somewhat improvement for a short period of time. However, as time went on, the patients showed no obvious improvement in their life quality. The dimensions of independence and social activity in QOL also showed significantly different between these two groups. The results may provide guides on designing programs and activities for the chronic mental patients. However, the best decision to apply which program for patients need continouous and comprehensive assessment.

Economic feasibility analysis for an automated on-line poultry inspection technology

On-line carcass inspection of chickens in the United States is currently done using visual (organoleptic) methods. Inspectors from the USDA Food Safety and Inspection Service (FSIS) inspect the viscera and carcass and, for older birds, the heads using a sequence of observations and palpations at a postmortem inspection station. The streamlined inspection system (SIS) and the new line speed inspection system (NELS) are the most prevalent visual inspection methods. The former has a line speed of 70 birds/min with two inspectors per line, and the latter has a line speed of 91 birds/min requiring three inspectors per line. Both inspection methods are labor intensive and prone to human error. In addition, the speed of the slaughter line is dictated by the number of birds per minute that can be inspected by FSIS inspectors. Ninety-one birds/min is currently the maximum visual inspection line speed allowed under current Federal regulations. This study evaluates the economic benefits of using automated inspection in place of visual inspection from the perspective of both the slaughter plant and FSIS. The results indicate that FSIS and slaughter plants would gain economic benefits by using automated inspection in place of visual inspection. The economic benefits to FSIS would accrue from labor savings, whereas the economic benefits to slaughter plants would accrue primarily from increased throughput from faster inspection line speeds.

The race of the millennium: CD-ROM versus the textbook

OBJECTIVE

To determine whether CD-ROMs are as fast as everyone thinks they are.

METHODS

A grand contest between 2 textbooks and their electronic versions, held with the help of 10 victims.

RESULTS AND INTERPRETATION

We can't be expected to tell you that now. You'll have to read the paper.

Levothyroxine suppression of thyroglobulin in patients with differentiated thyroid carcinoma

For patients with differentiated thyroid carcinoma, the appropriate degree of TSH suppression by levothyroxine (L-T4) is still unknown. To find the target level of TSH suppression, we analyzed the relationship between the degree of TSH suppression determined by third generation assay and thyroglobulin (Tg) response during the titration of the dosage of L-T4. Ninety-two patients with differentiated thyroid carcinoma (19 males and 73 females; age, 40.5+/-13.5, mean +/- SD) were included. All of the recruited patients had near-total thyroidectomy, 30-150 mCi 131I thyroid ablation, and negative Tg autoantibodies. They were classified into 3 groups. Group A was composed of 25 patients with local or distant relapse. Group B was composed of 12 patients without clinically detectable relapse, but Tg levels either above 2 ng/mL under L-T4 suppression or above 3 ng/mL off L-T4 therapy. Group C included 55 patients who had no active disease and Tg levels below 2 and 3 ng/mL during and off L-T4 suppression, respectively. Serum TSH and Tg were measured simultaneously at the end of 8-12 weeks of a certain dose of L-T4 therapy during dosage titration and also after withdrawal of L-T4 for 4-6 weeks for the total body scan. Wilcoxon signed ranks test was used to compare paired samples of Tg, and Spearman rank correlation was used to determine the correlation of relative changes in TSH to changes in Tg calculated by individual. The results showed that 1) Tg levels were significantly higher during the period off L-T4 therapy than on L-T4, therapy in all 3 groups (P < 0.01); 2) during L-T4, therapy, within the same treatment course, mean Tg levels were higher when TSH levels were normal than when TSH levels were suppressed, statistically significant in group A (P = 0.001), nonsignificant in group B (P = 0.09), and nonsignificant in group C (P = 0.30); and 3) when TSH was suppressed below normal, there was no correlation between the relative changes in TSH and Tg by individual in all 3 groups (P > 0.05). The data suggest a stratified postoperative thyroid hormone management of patients with differentiated thyroid carcinoma. TSH should be lowered to below normal in patients with active disease. If patients are clinically disease free with Tg levels below 2 ng/mL, TSH can be kept within the normal range. For the most controversial group B patients, it is recommended that the TSH be suppressed and be closely followed up.

Corticotropin releasing factor and substance P mediate the nucleus amygdaloideus centralis-nucleus ventromedialis-nucleus dorsomedialis pressor system

Prolonged emotional stress is an important factor in the development of neurogenic hypertension, but its mechanism is still unclear. The purpose of the present study is to analyze the possible neural basis of hypertension induced by prolonged emotional stress. In the brain many nuclei are involved in emotional reaction, stress or defense response; among them the nucleus amygdaloideus centralis (AC) is the most important one which widely connects with other nuclei controlling emotion and stress, such as nucleus ventromedialis (NVM), nucleus dorsomedialis (NDM), nucleus paraventricularis (NPV) etc. These nuclei contain corticotropin releasing factor (CRF)- and substance P (SP)-immunoreactive cell bodies, nerve terminals and corresponding receptors. Our previous and present studies showed that microinjection of CRF or SP into these nuclei induced pressor responses. These data imply that excitation of the AC can activate many nuclei controlling emotion and stress via CRF and SP, and excessive activities of these nuclei may be the neural basis of hypertension induced by prolonged emotional stress. The present study revealed that (1) the AC pressor response to glutamate (Glu) could be reduced by preinjection of CRF antagonist (alpha-Helical CRF[9-41] or SP antagonist ([D-Pro(2), D-Phe(7), D-Trp(9)]-substance P) into bilateral NVM, (2) the NVM pressor response to Glu were decreased by pretreatment of the NDM with CRF- or SP-antagonist, (3) the AC-, NVM- or NDM-pressor responses were all attenuated by preinjection of CRF- or SP-antagonist into bilateral NPV or rostral ventrolateral medulla (RVL). The results indicate that excitation of the AC can indirectly activate the NPV and RVL to evoke pressor response via the NVM-NDM, CRF and SP are transmitters in each connection of this pathway; this is one component of the mechanism underlying the AC pressor response. Taken together with the findings of our previous studies, it provides neurophysiological basis for the above-mentioned implications.

Acute disseminated histoplasmosis complicated with hypercalcaemia

A case of acute progressive disseminated histoplasmosis complicated with hypercalcemia is reported and the literature is reviewed. This and the previously reported cases imply that physicians should have a higher index of suspicion for this infection and the probable underlying diseases resulting from impaired cellular-mediated immunity when encountering patients with hypercalcaemia.

Intra-articular gouty tophi of the knee: CT and MR imaging in 12 patients

OBJECTIVE

To define the imaging characteristics of intra-articular tophi of the knee.

DESIGN AND PATIENTS

Twelve patients with intra-articular tophi in the knee were studied with routine MR imaging, gadolinium (Gd)-enhanced MR imaging, and CT over a 4-year period. There were 11 men and one woman, 25-82 years of age (mean age 48 years). Four patients did not have a documented history of gout at the time of the MR examination. The diagnosis of intra-articular tophi was provided by arthroscopy and histological examination (5 patients), by microscopic study of joint fluid (5 patients), or by characteristic clinical, laboratory and imaging findings (2 patients).

RESULTS

In 15 MR examinations the tophi were located purely intra-articularly in 10 knees. In the remaining five MR studies, periarticular soft tissues or bone, or both, were involved. All the intra-articular tophi manifested low to intermediate signal intensity on both T1- and T2-weighted images. All five Gd-enhanced MR examinations demonstrated a heterogeneous peripheral enhancement. All 10 CT scans showed varying degrees of stippled calcifications within the tophi. The nature of the calcifications was confirmed on histological examination in three patients.

CONCLUSION

Presenting clinical manifestations of gout may relate to intra-articular tophaceous deposits. Such deposits present as masses on MR images with low to intermediate signal intensity on both T1- and T2-weighted images and a characteristic enhancement pattern following intravenous Gd administration. These features relate primarily to internal calcifications, which are most evident on CT images. MR evaluation (including Gd administration) supplemented, in some cases, with CT scanning allows accurate diagnosis of intra-articular tophaceous deposits.

Co-regulation of tissue-specific alternative human carnitine palmitoyltransferase Ibeta gene promoters by fatty acid enzyme substrate

Carnitine palmitoyltransferase I (CPT-I) catalyzes the rate-determining step in mitochondrial fatty acid beta-oxidation. CPT-I has two structural genes (alpha and beta) that are differentially expressed among tissues. Our CPT-Ibeta isolates from a human cardiac cDNA library contained two different extreme 5'-sequences derived from short alternative first untranslated exons that utilize a common splice acceptor site in exon 2. Primer extension identified single dominant start sites for each transcript, and ribonuclease protection assays showed the presence of one 5'-exon in liver, muscle, and heart mRNAs, indicating that the cognate promoter U (upstream/ubiquitous) is active in each of these tissues. By contrast, mRNAs containing the alternative 5'-exon were present only in muscle and heart, indicating a muscle-specific promoter M (muscle). CPT-Ibeta mRNA levels increased markedly in tissues of fasted rats, when circulating free fatty acid concentrations are elevated. Using CPT-Ibeta promoter/reporter transient transfection of murine C2C12 myotubes and HepG2 hepatocytes, fatty acids were found to increase promoter activity in a peroxisome proliferator-activated receptor alpha (PPARalpha)-dependent fashion. A promoter fatty acid response element (FARE) was mapped, mutation of which ablated fatty acid-mediated production of both transcripts. PPARalpha/retinoid X receptor alpha formed specific complexes with oligonucleotides containing the FARE, and anti-PPARalpha antibody shifted nuclear protein-DNA complexes, confirming the role of this factor in regulating the expression of this critical metabolic enzyme gene. The constitutive repressor chicken ovalbumin upstream promoter transcription factor competitively binds at the FARE and modulates fatty acid induction of the promoters.

Outcome of Graves' disease after antithyroid drug treatment in Taiwan

The outcome of Graves' disease after treatment with antithyroid drugs (ATDs) varies widely among countries, and large-scale studies in Asia are rare. We investigated the associations of various clinical and laboratory features with the outcome of ATD therapy for Graves' disease in Taiwan. A total of 210 patients (177 women, 33 men; mean +/- SD age, 41.7 +/- 15.1 yr) treated with ATD in Taiwan were included. ATD therapy started with methimazole 30 mg daily or propylthiouracil 300 mg daily and was continued until a euthyroid state was achieved. Afterwards, 154 patients received a maintenance dose of ATD alone, while 56 patients received a combination of an ATD and thyroxine (L-T4). Patients were considered to be in remission if they remained in a euthyroid state for more than 2 years after drug withdrawal. The mean follow-up periods were 45.0 +/- 20.9 months for patients with remission and 30.4 +/- 19.8 months for those with relapse. Relapse occurred in 126 (60%) patients during the follow-up period, within 3 months after drug withdrawal in 47 (37%), and within 6 months in 60 (46%). The relapse rate was 100% among patients with two or more previous relapses. Patients with a second occurrence had a higher relapse rate than those with a first occurrence (84% vs 43%). Past history of recurrence, goiter size, thyroid-stimulating hormone level and thyrotropin-binding inhibition immunoglobulin activity at the end of ATD treatment were independently associated with relapse. Prolonged duration of treatment did not yield better results in patients with larger goiters or a history of recurrence, or both. Combination therapy with L-T4 yielded similar results to those achieved with ATD treatment alone. In conclusion, the relapse rate of Graves' disease after ATD treatment in Taiwanese patients was high, especially in those with a history of recurrence. The treatment duration and drug regimen did not affect the outcome.

Expression of novel isoforms of carnitine palmitoyltransferase I (CPT-1) generated by alternative splicing of the CPT-ibeta gene

Carnitine palmitoyltransferase I (CPT-I) catalyses the rate-determining step in mitochondrial fatty acid beta-oxidation. The enzyme has two cognate structural genes that are preferentially expressed in liver (alpha) or fat and muscle (beta). We hypothesized the existence of additional isoforms in heart to account for unique kinetic characteristics of enzyme activity in this tissue. Hybridization and PCR screening of a human cardiac cDNA library revealed the expression of two novel CPT-I isoforms generated by alternative splicing of the CPT-Ibeta transcript, in addition to the beta and alpha cDNA species previously described. Ribonuclease protection and reverse transcriptase-mediated PCR assays confirmed the presence of mRNA species of each splicing variant in heart, skeletal muscle and liver, with differing relative concentrations in the tissues. The novel splicing variants omit exons or utilize a cryptic splice donor site within an exon. Deduced polypeptide sequences of the novel enzymes include omissions in the region of putative membrane-spanning and malonyl-CoA regulatory domains compared with the previously described CPT-Is, implying that the encoded enzymes will exhibit unique features with respect to outer mitochondrial membrane topology and response to physiological and pharmacological inhibitors.

Rat carnitine palmitoyltransferase Ibeta mRNA splicing isoforms

Carnitine palmitoyltransferase I (CPT-I) catalyzes the rate-determining step in mitochondrial fatty acid beta-oxidation. The enzyme has two cognate structural genes (alpha and beta) that are differentially expressed in tissues. We show multiple mature mRNAs in rat heart derived from alternative splicing of CPT-Ibeta transcripts. Two novel messages are deleted for regions of the previously described mRNA that encode membrane-spanning and regulatory domains, suggesting that the cognate isozymes will exhibit unique kinetic characteristics.

Endobronchial metastasis from an occult papillary thyroid carcinoma: a case report

It is well known that occult papillary thyroid cancers can result in regional lymph node metastasis. However, this small, clinically undetectable cancer rarely causes distant metastasis; moreover, an endobronchial presentation has not been described previously. We report on a 48-year-old man who experienced hemoptysis. A fiberoptic bronchoscopic biopsy established the diagnosis of endobronchial metastasis in the absence of clinically apparent thyroid cancer. After the patient was treated with a total thyroidectomy and radioactive iodine (131I), a whole body radioiodine scan revealed no evidence of distant functioning metastasis. A histological evaluation of the thyroid gland showed the presence of a 0.2 x 0.2 x 0.2 cm nodule in the right lobe. A left pneumonectomy was undertaken to treat the distant metastasis of the disease. Since most papillary thyroid carcinomas are curable, an aggressive surgical approach to the solitary metastasis is indicated.

[Role of substance P in pressor response of central amygdaloid nucleus to glutamate]

Substance P (SP)-immunoreactive cells and the axon terminals are widely distributed in the central amygdaloid nucleus (AC) and its important projection areas. The present study showed that (1) Excitation of the AC by glutamate (Glu) or injection of SP into the AC projection areas: locus coeruleus (LC), nucleus parabrachialis (NPB), periaqueductal gray matter (PAG) or lateral hypothalamus-perifornical region (LH/PF), all elicited pressor response. (2) Preinjection of DPDPDT (a SP antagonist) into bilateral LC, NPB, PAG or LH/PF could attenuate the AC pressor response to Glu. (3) Intra-RVLM (rostral ventrolateral medulla) preinjection of either phentolamine, propranolol or atropine (but not GDEE, a Glu antagonist) could also reduce the AC pressor response. Taken together with our previous findings that the alpha-, beta-, M-receptors in RVLM mediated the pressor response to LC excitation, alpha-receptors mediated the NPB pressor response, alpha- and beta-receptors mediated the PAG pressor response; these results indicate that the SPergic projections of the AC not only directly act upon the brainstem pressor areas (LC, NPB, PAG)-RVLM system, but also indirectly via the LH/PF act upon the brainstem pressor areas-RVLM system to induce the pressor response.

Hormonal responses to psychological stress in men preparing for skydiving

The purpose of the study was to examine the relationship between the hormonal and psychological responses of young men about to engage in a potentially life-threatening event. Subjects were recruited to take their first skydiving jump. The scores on questionnaires designed to assess anxiety were not significantly increased at 0800 h on the morning before the jump by comparison with scores obtained from the same subjects 3-5 days previously. However, a psychological instrument for rating of events indicated significantly increased intensity, and sympathetic nervous system activity, as measured by the salivary amylase response, was increased over self-control values. Salivary cortisol and testosterone levels were significantly lower on the morning of the jump than self-control values and values in control subjects determined at the same time of day. However, plasma LH was not suppressed. The anxiety and stress measures as well as the rating of events rose to high levels just before the jump. With the exception of testosterone, which remained low, serum cortisol, PRL, and GH all increased greatly subsequent to the rise in psychological measures, reached peak values before or shortly after landing, and declined significantly within the next hour. Anxiety and subjective stress scores declined to those of the self-control values within 15 min after landing, but the rating of events scale remained significantly elevated. In summary, reported anxiety associated with a purely psychological stressor was suppressed until within a few hours preceding the event, but was preceded by an increase in sympathetic nervous system activity and suppression of plasma cortisol and salivary testosterone levels. The event itself was associated with a reversal of the cortisol decline; other stress-associated hormones increased, but salivary testosterone remained low.

Direct radioimmunoassay of progesterone in saliva

We have developed a simple, direct radioimmunoassay for progesterone in saliva. The correlation coefficient (r) between the direct assay and an extraction procedure was 0.92 (n = 65, P < 0.001), and the correlation between concurrent serum and salivary progesterone concentrations in the luteal phases of menstrual cycles of 48 women was 0.75 (P < 0.001). Whereas certain polystyrene and polyethylene vials and tubes were found to bind and remove up to 87% of the progesterone from saliva, other plastic and glass surfaces were satisfactory for the procedure. Intraassay and interassay CVs from values greater than 300 pmol/L were 12.0 and 12.4%, respectively. The assay sensitivity was 48 pmol/L. Collection of saliva is a more convenient and less invasive technique for frequent sample collection than phlebotomy, and is useful for monitoring ovulation and assessment of luteal function in women clinically.

[Involvement of nucleus amygdaloideus centralis, lateral hypothalamus/perifornical region and nucleus paraventricularis in insular cortex-pressor response]

In urethane-anesthetized, tubocurarine-immobilized and artificially ventilated rats, glutamate (Glu) injection into the insular cortex (INS) and substance P injection into the lateral hypothalamus-perifornical region (LH/PF) or nucleus paraventricularis (NPV) caused pressor responses. Preinjection of procaine or glutamate diethyl ester (GDEE, a glutamate antagonist) bilaterally into the nucleus amygdaloideus centralis (AC) and [D-Pro2, D-Phe7, D-Trp9]-substance P (DPDPDT, a substance P antagonist), but not GDEE, into the LH/PF markedly attenuated the pressor response induced by glutamate injection into the INS. Procaine or DPDPDT preinjection into the NPV also reduced the INS-pressor response. Since the LH/PF and NPV were found to mediate the AC-pressor response, the above results suggest that the INS-pressor response is the final outcome of activation of AC (Glu-receptor)-LH/PF and NPV (SP receptor) system.

Glucocorticoid remediable aldosteronism: a case report

Glucocorticoid remediable aldosteronism (GRA) is a hereditary cause of mineralocorticoid hypertension. The most common presentation is asymptomatic hypertension. Hypokalemia, hyperaldosteronism and suppressed plasma renin activity are other forms of primary hyperaldosteronism. However, the aldosterone secretion in these patients is regulated by adrenocortico-tropic hormone (ACTH) rather than the reninangiotension system. Here, we report a patient with a 12-year history of hypertension without response to any treatment until dexamethasone was administered. The diagnosis of GRA was confirmed by elevated plasma level of 18-oxocortisol, which is a unique steroid biochemical abnormality of this disease. In GRA, hybrid steroids (18-oxocortisol and 18-hydroxycortisol) are synthesized at the C-18 carbon of cortisol in a similar way as when corticosterone is converted to aldosterone. The gene duplication defect is on chromosome 8 codes for a chimerical 11 beta-hydroxylase/aldosterone synthase enzyme, causing ectopic expression of aldosterone synthase in zona fasiculata. Because this hypertension is remediable by exogenous glucocorticoid, this case was reported to raise attention about treatable aldosteronism.

Inhibition of nitric oxide synthase potentiates hypertension and increases mortality in traumatically brain-injured rats

We examined the effects of N omega-nitro-L-arginine methyl ester (L-NAME), an inhibitor of nitric oxide synthase (NOS), on mortality, morbidity, and cardiovascular parameters following traumatic brain injury (TBI) in the rat. Rats were anesthetized with 2% isoflurane prior to moderate (2.0 atmosphere), central fluid percussion TBI. Temporalis muscle temperature was maintained at 37 +/- 0.5 degrees C. L-NAME (10 mg/kg iv) was administered once at either 5 min before, 5 min after, or 15 min after TBI. Sensorimotor deficits and spatial learning/ memory deficits were assessed after injury. Separate groups of rats were monitored for cardiovascular parameters. Preinjury administration of L-NAME significantly increased mortality from 13 (vehicle) to 70% (associated with pulmonary edema), whereas postinjury, L-NAME had no effect on mortality (14 and 25%). L-NAME administered at 5 or 15 min after injury had no significant effect on motor performance or cognitive performance deficits associated with TBI. L-NAME in uninjured rats increased arterial blood pressure by 25 mmHg within 2 min. L-NAME injected 5 min before TBI greatly prolonged the hypertensive episode associated with TBI (1 min in vehicle vs 60 min in L-NAME). L-NAME injected 5 min after TBI caused a sustained 35 mmHg increase in blood pressure. These findings suggest that acute inhibition of NOS has detrimental consequences on mortality that may be owing to its cardiovascular effects.

Salivary alpha-amylase as a measure of endogenous adrenergic activity

This investigation was designed to evaluate the production rates and concentrations of salivary alpha-amylase as a measure of adrenergic activity under several conditions of stress in human subjects. Saliva and blood samples were simultaneously collected from men at four 15 min intervals both before and after regimens for exercise, a written examination, or a rest period. The regressions of salivary alpha-amylase on plasma norepinephrine (NE) concentrations were significant for both exercise (P < 0.001) and examination (P < 0.01) protocols. Aerobic exercise induced a 3-fold mean increase in alpha-amylase; both NE and epinephrine (EP) increased approximately 5-fold over control levels. Levels of alpha-amylase and NE returned to control levels within 30-45 min after exercise, but EP remained elevated by approximately 2-fold during the remaining hour of observation. During the written examination, alpha-amylase and NE, but not EP, concentrations increased in parallel. In further studies the effects of exercise and exposure to heat and cold on the relationship of salivary alpha-amylase to heart rate and body temperature were investigated. Greater intensities of exercise were associated with greater increases in alpha-amylase concentrations. During heat exposure in a sauna (66 degrees C for 40 min) amylase, heart rate and body temperature all increased progressively. However, during exposure to cold (4 degrees C for 40 min) amylase increased rapidly, though heart rate and body temperature remained unchanged. Salivary cortisol concentrations were unchanged during exposure to heat or cold. We conclude that salivary alpha-amylase concentrations are predictive of plasma catecholamine levels, particularly NE, under a variety of stressful conditions, and may be a more direct and simple end point of catecholamine activity than are changes in heart rate.

Ectopic parathyroid adenoma with severe hungry bone syndrome: a case report

The presentation rate of ectopic mediastinal parathyroid adenoma is about 5 approximately 22%. Ectopic parathyroid adenoma is a common etiology of failed parathyroid surgery as well as a diagnostic challenge to clinicians. We reported a case of ectopic mediastinal parathyroid adenoma. A 20-year-old girl presented with arthralgia for 2 years before hyperparathyroidism was diagnosed. Parathyroid ultrasonography failed to find the lesion, but a vivid uptake in the superior mediastinum was discovered by thallium-201 (Tl-201) and technetium-99m-sestamibi (Tc-99m-MIBI) images. Removal of the ectopic adenoma resulted in severe Hungry bone syndrome, which required a large amount of calcium and phosphorous supply. Later, the patient suffered from bilateral femoral neck fracture due to marked osteoporosis. Bone mineral density study revealed marked increase of fracture risk. Although bone disorder is rare in cases of hyperparathyroidism nowadays, it still should be considered in patients with arthritis of unknown etiology like our case. Early diagnosis and treatment can reduce the morbidity.

Vertical distortion in distal extension ridges and palatal area of casts made by different techniques

A coordinate measurement machine with laser probe was used to measure the vertical distortion of the casts produced by use of three types of impression materials (irreversible hydrocolloid, condensation silicone, and addition silicone) and two types of trays (stock and custom trays). Results indicated that all impression groups showed positive vertical distortion (ranging from 0.00566 to 0.30299 mm) at the edentulous ridges and palatal area. The amount of the vertical distortion was greatest at the palatal area and was followed by the high edentulous ridge and the low edentulous ridge. Addition silicone, with either custom tray or stock tray, was the most accurate impression material. Condensation silicone was more accurate than irreversible hydrocolloid in custom tray impression. However, in stock tray impression the irreversible hydrocolloid was more accurate than the condensation silicone. The results suggest that, with careful manipulation, irreversible hydrocolloid with stock tray impression may provide a satisfactory cast for fabricating the framework of a distal extension removable partial denture.

Skin metastases from follicular thyroid carcinoma: a case report

Thyroid carcinomas metastasizing to the skin are rare. We report a case of skin metastases from a follicular thyroid carcinoma. A 73-year-old man developed multiple painless skin nodules about 6 years after thyroidectomy for the primary thyroid carcinoma. A biopsy disclosed a dermal tumor composed of small thyroid follicular structures with colloid material. The diagnosis was confirmed by immunohistochemistry using monoclonal antithyroglobulin antibodies performed on the skin biopsy specimens. The patient died 9 months later with multiple metastases after the development of skin lesions.

Antimicrobial resistance and serotype distribution of Streptococcus pneumoniae strains isolated in southern Taiwan

The antimicrobial susceptibilities and serotypes of 115 Streptococcus pneumonia strains isolated in southern Taiwan from January 1990 to December 1993 were determined. All isolates were susceptible to cephalothin, cefotaxime, trimethoprim/sulfamethoxazole and vancomycin, and 14 of the isolates were resistant to penicillin G. The oxacillin disk method for presumptive detection of resistance to penicillin had a sensitivity of 85.7% and specificity of 97.0%. Resistance rates were as follows: erythromycin 62.2%, tetracycline 71.3%, clindamycin 46.1% and chloramphenicol 19.1%. Eighty-four percent of the isolates were resistant to one or more of the antibiotic tested. Multiple resistance (to three or more classes of antibiotics) was identified in 40.9% of all the isolates and 100% of penicillin-resistant isolates. The predominant serotypes were: 14 (19.1%), 3 (17.4%), 23 (15.7%), 6 (10.4%), and 15 (6.1%). Serotypes 14 and 63 most commonly caused childhood infections, while serotypes 3 and 23 were frequently encountered in adults. The proportion of coverage in 23-valent pneumococcal polysaccharide vaccine was 92.2%, if vaccine-related serotypes were considered to be cross-protecting. Seven (58%) of 12 typable penicillin-resistant isolates belonged to serotype 23 and two (16.7%) to serotype 6. All isolates of serotype 14, 23, 15 and 19 were resistant to one or more antibiotics. Multiple drug resistance was frequently associated with serotype 23 (31.9%), 14 (23.4%) and 6 (17.0%). Sixty-five percent of isolates of serotype 3 were susceptible to all antibiotics tested. The high level of antimicrobial resistance in S. pneumoniae mandates the continuous surveillance of resistance and the strict control of antibiotic use in Taiwan.

A neural fuzzy system with fuzzy supervised learning

A neural fuzzy system learning with fuzzy training data (fuzzy if-then rules) is proposed in this paper. This system is able to process and learn numerical information as well as linguistic information. At first, we propose a five-layered neural network for the connectionist realization of a fuzzy inference system. The connectionist structure can house fuzzy logic rules and membership functions for fuzzy inference. We use alpha-level sets of fuzzy numbers to represent linguistic information. The inputs, outputs, and weights of the proposed network can be fuzzy numbers of any shape. Furthermore, they can be hybrid of fuzzy numbers and numerical numbers through the use of fuzzy singletons. Based on interval arithmetics, a fuzzy supervised learning algorithm is developed for the proposed system. It extends the normal supervised learning techniques to the learning problems where only linguistic teaching signals are available. The fuzzy supervised learning scheme can train the proposed system with desired fuzzy input-output pairs which are fuzzy numbers instead of the normal numerical values. With fuzzy supervised learning, the proposed system can be used for rule base concentration to reduce the number of rules in a fuzzy rule base. Simulation results are presented to illustrate the performance and applicability of the proposed system.