Rapid identification of Salmonella using Hektoen enteric agar and 16s ribosomal DNA probe-gold nanoparticle immunochromatography assay in clinical faecal specimens.

UNLABELLED: A rapid identification of Salmonella, one of the most common foodborne pathogens worldwide, in clinical patients can enable better rational managements and prevent further outbreaks. The traditional immunochromatography using antibody-gold nanoparticles (Ab-AuNPs), such as the home pregnancy test, has been used for the Salmonella detection. In this study, we developed a new and rapid method using DNA probe-AuNPs for the detection of 16s ribosomal DNA of Salmonella. To evaluate the proposed method in clinical specimens, we performed a clinical test by identifying 159 stool samples on Hektoen agar containing black or crystalloid colonies using the method and the VITEK 2 system for confirmation. Eighty of the isolates were correctly identified as Salmonella to achieve 100% sensitivity. Seventy-five samples were correctly identified as non-Salmonella spp., but four were incorrectly identified as Salmonella. The specificity was 94·93%. The assay time is about 30 min after the DNA purification. The time-consuming and labour-intense biochemical tests can be replaced. We demonstrated that this assay is a rapid, convenient and cost-effective tool for Salmonella identification of clinical faecal samples, which is worth for further promotion and clinical use. This is the first application of using 16s ribosomal DNA probe-Au-NPs and immunochromatography on clinical samples. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first application of using 16s ribosomal DNA probe-gold nanoparticles and immunochromatography method on clinical samples with sensitivity 100% and specificity 94·93%. The assay time is about 30 min after the DNA purification. We find this assay a rapid, convenient, sensitive and inexpensive tool for Salmonella identification of clinical faecal samples, which is worth further promotion and clinical use and can replace the traditional time-consuming and labour-intense biochemical tests. The potential benefit of this approach is to develop a rapid point-of-care test that provides results while the patient is still at the doctors' office.

Hemichorea associated with gabapentin therapy with hypoperfusion in contralateral basal ganglion - a case of a paraplegic patient with neuropathic pain.

Functional imaging in patients with movement disorders has suggested abnormalities of regional cerebral blood flow (rCBF). We describe a patient with thoracic cord lesion with subsequent severe neuropathic pain. Right hemichorea developed and was related to adjunctive therapy with gabapentin. The patient's hemichorea decreased gradually after cessation of gabapentin. The study of rCBF revealed hypoperfusion in the contralateral basal ganglia compared with the previous study of rCBF. Our patient is the first patient with neuropathic pain, treated with gabapentin who developed hemichorea, in the absence of brain lesions. Imaging studies of rCBF showed a perfusion defect in the contralateral basal ganglion.

Effects of piroxicam-beta-cyclodextrin sachets on abnormal postural sway in patients with chronic low back pain.

BACKGROUND: The clinical effects of piroxicam-beta-cyclodextrin (PBC) in sachet form have been surveyed in patients with osteoarthritic or acute pain in western countries, but scarcely studied in those with chronic low back pain (LBP), and never investigated in the field of postural sway. The aim of this study was to evaluate the clinical effects of PBC in sachet form prescribed in patients with chronic backache in local Asian when compared with those of plain piroxicam. METHODS: After randomized allocation and experimental exclusion, a total of 42 eligible patients were randomized into two groups, the sachet group (n = 23) and the piroxicam tablet group (n = 19). Both groups were administered the same dosage, orally per day (daily dose = 20 mg). The duration of trial was 28 days. Efficacy was assessed with pain score, disability index and postural sway. RESULTS: The patients in sachet group showed greater improvement in pain score and disability index than those who took piroxicam tablets. There were significantly lower sway velocity and intensity at almost all different conditions than baseline profiles in both groups (P < 0.05). However, there was no significant difference of sway velocity and intensity in the piroxicam tablets group with regard to eyes open or eyes closed in 20 degrees dorsiflexion. CONCLUSIONS: Piroxicam-beta-cyclodextrin (PBC) sachet may have greater improvement in the treatment of chronic LBP and possess the extended effects on postural abnormality relevant to chronic LBP.

Protein disulfide isomerase a4 acts as a novel regulator of cancer growth through the procaspase pathway.

Protein disulfide isomerase a4 (PDIA4) is implicated in the growth and death of tumor cells; however, its molecular mechanism and therapeutic potential in cancer are unclear. Here, we found that PDIA4 expression was upregulated in a variety of tumor cell lines and human lung adenocarcinoma tissues. Knockdown and overexpression of PDIA4 in tumor cells showed that PDIA4 facilitated cell growth via the reduction of caspases 3 and 7 activity. Consistently, Lewis lung carcinoma cells overexpressing PDIA4 grew faster than did parental cells in tumor-bearing mice, as shown by a reduced survival rate, increased tumor size and metastasis, and decreased cell death and caspases 3 and 7 activity. PDIA4 knockdown resulted in opposite outcomes. Moreover, results obtained in mice with spontaneous hepatoma indicated that PDIA4 deficiency significantly reduced hepatic tumorigenesis and cyst formation and increased mouse survival, tumor death, and caspases 3 and 7 activity. Mechanistic studies illustrated that PDIA4 negatively regulated tumor cell death by inhibiting degradation and activation of procaspases 3 and 7 via their mutual interaction in a CGHC-dependent manner. Finally, we found that 1,2-dihydroxytrideca-5,7,9,11-tetrayne, a PDIA4 inhibitor, reduced tumor development via enhancement of caspase-mediated cell death in TSA tumor-bearing mice. These findings characterize PDIA4 as a negative regulator of cancer cell apoptosis and suggest that PDIA4 is a potential therapeutic target for cancer.

Role of highly conserved pyrimidine-rich sequences in the 3' untranslated region of the GAP-43 mRNA in mRNA stability and RNA-protein interactions.

We have shown previously that the mRNA for the growth-associated protein GAP-43 is selectively stabilized during neuronal differentiation. In this study, we explored the role of its highly conserved 3' untranslated region (3'UTR) in mRNA stability and RNA-protein interactions. The 3'UTRs of the rat and chicken GAP-43 mRNAs show 78% sequence identity, which is equivalent to the conservation of their coding regions. In rat PC12 cells stably transfected with the full-length rat or chicken GAP-43 cDNAs, the transgene mRNAs decayed with same half-life of about 3 h. The GAP-43 3'UTR also caused the rabbit beta-globin mRNA to decay with a half-life of 4 h, indicating that the major determinants for GAP-43 mRNA stability are localized in its highly conserved 3'UTR. Three brain cytosolic RNA-binding proteins (molecular mass 40, 65 and 95 kDa) were found to interact with both the rat and chicken GAP-43 mRNAs. These RNA-protein interactions were specific and involved pyrimidine-rich sequences in the 3'UTR. Like the GAP-43 mRNA, the activity of these proteins was enriched in brain and increased during development. We propose that highly conserved pyrimidine-rich sequences in the 3'UTR of this mRNA regulate GAP-43 gene expression via interactions with specific RNA-binding proteins.

cis-acting regulatory elements in the GAP-43 mRNA 3'-untranslated region can function in trans to suppress endogenous GAP-43 gene expression.

The expression of the GAP-43 gene is controlled partly by changes in the stability of its mRNA, a process that is mediated by the interaction of specific sequences in the 3'-untranslated region (3'UTR) with neuronal-specific RNA-binding proteins. Limiting amounts of these trans-acting factors are available in the cell, thus we proposed that overexpression of the GAP-43 3'UTR could affect the levels of the endogenous mRNA via competitive binding to specific RNA-binding proteins. In this study, we show that chronic expression of GAP-43 3'UTR sequences in PC12 cells causes the depletion of the endogenous mRNA and consequent reduction of GAP-43 protein levels. The levels of the mRNAs for c-fos, the amyloid precursor protein (APP) and the microtubule associated protein tau, all three containing similar 3'UTR sequences, were not affected by the treatment. These results thus suggest that the effect of excess GAP-43 3'UTR is specific for its corresponding mRNA. We also used an HSV (herpes simplex virus)-1 vector and a mammalian expression vector with an inducible promoter to acutely express a 10 to 50 fold excess of 3'UTR sequences. Under these conditions, we found that transient expression of the GAP-43 3'UTR was effective in inhibiting both GAP-43 gene expression and neurite outgrowth in nerve growth factor (NGF)-treated PC12 cells and in primary neuronal cultures. These results underscore the role of 3'UTR sequences in the control of GAP-43 gene expression and suggest that overexpression of specific 3'UTR sequences could be used as a potential tool for probing the function of other post-transcriptionally-regulated proteins during neuronal differentiation.

Sharing patient care records over the World Wide Web.

In order to obtain appropriate medical care, patients can be referred or transported from one hospital to another based on the capacity, capability and quality of medical care provided by hospitals. Therefore, enabling patient care records to be shared among hospitals is essential not only in delivering the quality of medical care services but also in saving medical expenses. Currently, most patient care records are paper-based and not well organized. Hence, they are usually incomplete and can hardly be accessed in time. The authors in this paper present methods to structure and represent patient care records, design mechanisms for interpreting and integrating the XML-based patient care records into the existing hospital information systems. More importantly, in our approach, each significant piece of medical record is associated with a tag based on the syntax and semantics of the XML. The XML-based medical records enable a computer to capture the meaning and structure of the document on the web. The authors have developed a unified referral information system in which patient care records can be shared among hospitals over the Internet. It can not only facilitate the referral process but also maintain the integrity of a patient's medical record from distributed hospitals. The workflow of the system basically follows the existing manual system and can easily be adapted. The working group on integration of municipal hospital information systems, Department of Health, Taipei City Government, has decided to adapt this system for referral practice among the municipal hospitals.

Sonoporation-mediated anti-angiogenic gene transfer into muscle effectively regresses distant orthotopic tumors.

Ultrasound (US) is an effective tool for local delivery of genes into target tumors or organs. In combination with microbubbles, US can temporarily change the permeability of cell membranes by cavitation and facilitate entry of plasmid DNA into cells. Here, we demonstrate that repeated US-mediated delivery of anti-angiogenic genes, endostatin or calreticulin, into muscle significantly inhibits the growth of orthotopic tumors in the liver, brain or lung. US-mediated anti-angiogenic gene therapy also seems to function as an adjuvant therapy that significantly enhances the antitumor effects of the chemotherapeutic drug doxorubicin and adenovirus-mediated cytokine gene therapy. Significantly higher levels of tumor apoptosis or tumor-infiltrating lymphocytes were observed after combined therapy consisting of either anti-angiogenic therapy and chemotherapy, or anti-angiogenic therapy and immunotherapy. Taken together, our experiments demonstrate that intramuscular delivery of anti-angiogenic genes by US exposure can effectively treat distant orthotopic tumors, and thus has great therapeutic potential in terms of clinical treatment.

The effects of power on-off durations of pulsed ultrasound on the destruction of cancer cells.

PURPOSE: Low-intensity ultrasound irradiation is a potential method for suppressing cancer cell proliferation, inducing apoptosis and delivering specific cytotoxic genes or drugs into tumors topographically in future cancer therapies. However, ultrasound attenuates rapidly in tissue and produces heat. Pulsed ultrasound is frequently used to minimize pain and possible thermal damage to the surrounding normal tissue during therapy, since it results in smaller temperature increases. This study compared three pulsed-ultrasound strategies for destroying cancer cells, measuring their induced temperature increases to determine the optimal pulsing parameters. MATERIALS AND METHODS: We performed three types of experiment, involving ultrasound with (1) a fixed duty cycle of 50% with variable on- and off-times, (2) a fixed off-time with variable on-times, and (3) a fixed on-time with variable off-times. RESULTS: The results show that for different types of cultured cells (HeLa, HT-29, Ca9-22 and fibroblast) exposed to ultrasound of the same frequency (1 MHz) and energy, long pulses combined with off-times that are 5-10 times longer (on-/-off-times pairs of 5/25, 25/250, or 250/2500 ms/ms) cause significant cell destruction whilst avoiding temperature increases of more than 1.5 degrees C. Furthermore, the correlation between the temperature increase and the percentage of surviving cells is low. CONCLUSIONS: Pulsed ultrasound with a long on-time and an even longer off-time exerts a high cytotoxic effect but a smaller temperature increase compared with non-pulsed ultrasound. This indicates that the cytotoxic effects observed in the current study were not purely due to the thermal effects of the ultrasound.

Spontaneous pneumothorax associated with ankylosing spondylitis.

OBJECTIVE: To review the incidence and clinical characteristics of spontaneous pneumothorax in patients with ankylosing spondylitis (AS). METHODS: This is a retrospective observational cohort study. Chest radiographs and medical records of patients with a diagnosis of AS from 1993 to 2003 in a tertiary referral centre were reviewed. RESULTS: A total of 1028 patients with a diagnosis of AS were identified from July 1993 to July 2003. Twenty-two patients had typical apical lung fibrotic changes in the chest radiographs (22/1028, 2.1%). Three of these patients (3/22, 13.6%) with lung disease had pneumothorax. Two patients had recurrences and received video-assisted thoracoscopic surgery (VATS) on the second attack. The third patient received talc pleurodesis on the first attack and did not have a recurrence. The incidence of spontaneous pneumothorax in patients with AS was 0.29% (3/1028) with an incidence density of 64.85/100,000 patient-yr (95% confidence interval: 66.17-63.57/100,000). CONCLUSION: Spontaneous pneumothorax appears to be exceedingly rare in AS unless there is an underlying fibrocystic lung disease, in which case its occurrence is not uncommon. Cigarette smoking may be an important co-factor. Once developed, recurrences are common even after treatment. Prophylactic procedures should thus be considered for the first attack of spontaneous pneumothorax.

Preoperative sonographic diagnosis of sealed-off perforated gastric ulcer.

Perforated peptic ulcer (PPU) is a common surgical emergency. Early diagnosis and intervention are necessary to reduce the morbidity and mortality. Radiographic or sonographic detection of free air is neither sensitive nor specific for PPU. We report a case of sealed-off PPU with direct sonographic demonstration of the perforation tract within the anterior wall of the gastric antrum. The diagnosis was confirmed at laparotomy.

Post-transcriptional regulation of the GAP-43 gene by specific sequences in the 3' untranslated region of the mRNA.

We have shown previously that GAP-43 gene expression during neuronal differentiation is controlled by selective changes in mRNA stability. This process was found to depend on highly conserved sequences in the 3' untranslated region (3' UTR) of the mRNA. To map the sequences in the GAP-43 3' UTR that mediate this post-transcriptional event, we generated specific 3' UTR deletion mutants and chimeras with the beta-globin gene and measured their half-lives in transfected PC12 cells. Our results indicate that there are two distinct instability-conferring elements localized at the 5' and 3' ends of the GAP-43 3' UTR. Of these destabilizing elements, only the one at the 3' end is required for the stabilization of the mRNA in response to treatment with the phorbol ester TPA. This 3' UTR element consists of highly conserved uridine-rich sequences and contains specific recognition sites for two neural-specific GAP-43 mRNA-binding proteins. Analysis of the levels of mRNA and protein derived from various 3' UTR deletion mutants indicated that all mutants were translated effectively and that differences in gene expression in response to TPA were attributable to changes in GAP-43 mRNA stability. In addition, the phorbol ester was found to affect the binding of specific RNA-binding proteins to the 3' UTR of the GAP-43 mRNA. Given that, like the GAP-43 mRNA, its degradation machinery and the GAP-43 mRNA-binding proteins are expressed primarily in neural cells, we propose that these factors may be involved in the post-transcriptional regulation of GAP-43 gene expression during neuronal differentiation.