A rapid and high-throughput quantitation assay of the nuclear factor κB activity using fluorescence correlation spectroscopy in the setting of clinical laboratories.

BACKGROUND: Transcription factor nuclear factor-κB (NF-κB) plays a key role in the regulation of immune responses to inflammation. However, convenient assay systems to quantitate the NF-κB activity level in a timely manner are not available in the setting of clinical laboratories. Therefore, we developed a novel and high-throughput quantitative assay based on fluorescence correlation spectroscopy (FCS) to detect the NF-κB activity level in cellular nuclear extracts and evaluated the performance of this method. The basic principle of this assay is to calculate the binding fraction of NF-κB to fluorescent-labeled DNA probes, which contain NF-κB binding sites. METHODS: Non-fluorescent competitive probes are employed to normalize the influence of the viscosity of the nuclear extracts between samples and to eliminate the influence of nonspecific binding of the fluorescent probes. To confirm accurate quantitation, human recombinant NF-κB p50 was mixed into U937 cell nuclear extracts, and the binding fraction of the fluorescent probes to NF-κB in the mixture was calculated for quantitation. To evaluate whether this method can be applied to measure the NF-κB activity in human lymphocytes, the NF-κB activity levels of systemic inflammatory response syndrome patients during perioperative periods were measured. RESULTS: The percentage recovery was 88.9%. The coefficients of variation of the intra-assay were approximately 10%. NF-κB activity levels during the perioperative period can were successfully measured. The assay time for the FCS measurement was within 20 minutes. CONCLUSIONS: This assay system can be used to quantitate NF-κB activity levels in a timely manner in the setting of hospital laboratories.

[Comments on routine laboratory data that are of practical use for physicians].

Routine laboratory data are not adequately used to follow a patient because medical students are not educated to comprehend them with time series analysis. The Department of Laboratory Medicine can support physicians by adding comments to laboratory data that are of practical use for following a patient. At Shinshu University School of Medicine, routine laboratory data are discussed by time series analysis in a reversed clinicopathological conference(R-CPC). The general status is checked and then the state of each organ is examined using routine laboratory data, and we can obtain much more information about the patient than from physical examinations. In this R-CPC, several specialists in laboratory medicine discussed routine laboratory data of a patient with severe inflammation. It was difficult to diagnose him with a bacterial infection. Elevation of white blood cell count and high C-reactive protein suggested bacterial infection, and decreased platelets showed the possibility of bacteremia. However, he was clinically diagnosed as having multiple trauma without bacterial infection after falling down a mountainside. If routine laboratory data are finely analyzed by specialists in laboratory medicine, physicians can obtain useful information for patient treatment from the Department of Laboratory Medicine.

Distribution of serine/threonine kinase SAD-B in mouse peripheral nerve synapse.

The serine/threonine kinase SAD regulates neural functions such as axon/dendrite polarization and neurotransmitter release. In the vertebrate central nervous system, SAD-B, a homolog of Caenorhabditis elegans SAD-1, is associated with synaptic vesicles and the active zone cytomatrix in nerve terminals. However, the distribution of SAD-B in the peripheral nervous system remains elusive. Here, we show that SAD-B is specifically localized to neuromuscular junctions. Although the active zone protein bassoon showed a punctated signal indicating its localization to motor end plates, SAD-B shows relatively diffuse localization indicating its association with both the active zone and synaptic vesicles. Therefore, SAD kinase may regulate neurotransmitter release from motor end plates in a similar manner to its regulation of neurotransmitter release in the central nervous system.

[Genetic diagnostics of pathogenic splicing abnormalities in the clinical laboratory--pitfalls and screening approaches].

In recent years, genetic diagnostics of pathogenic splicing abnormalities are increasingly recognized as critically important in the clinical genetic diagnostics. It is reported that approximately 10% of pathogenic mutations causing human inherited diseases are splicing mutations. Nonetheless, it is still difficult to identify splicing abnormalities in routine genetic diagnostic settings. Here, we studied two different kinds of cases with splicing abnormalities. The first case is a protein S deficiency. Nucleotide analyses revealed that the proband had a previously reported G to C substitution in the invariant AG dinucleotide at the splicing acceptor site of intronl/exon2, which produces multiple splicing abnormalities resulting in protein S deficiency. The second case is an antithrombin (AT) deficiency. This proband had a previously reported G to A substitution, at nucleotide position 9788 in intron 4, 14 bp in front of exon 5, which created a de novo exon 5 splice site and resulted in AT deficiency. From a practical standpoint, we discussed the pitfalls, attentions, and screening approaches in genetic diagnostics of pathogenic splicing abnormalities. Due to the difficulty with full-length sequence analysis of introns, and the lack of RNA samples, splicing mutations may escape identification. Although current genetic testing remains to be improved, to screen for splicing abnormalities more efficiently, it is significant to use an appropriate combination of various approaches such as DNA and/or RNA samples, splicing mutation databases, bioinformatic tools to detect splice sites and cis-regulatory elements, and in vitro and/or in vivo experimentally methods as needed.

[Problems facing undergraduate clinical practice training in laboratory medicine and proposed solution: remodeling of a point-of-care automatic analyzer].

It is essential that medical students learn how to precisely assess the results of laboratory tests. This may be accomplished by improving students' understanding of the processes involved in the laboratory testing of specimens, from blood collection to analysis, and by discovering factors that may influence these processes and impact results. Currently, medical students are generally taught the process by using a large automatic analyzer. However, because the students cannot observe the actual operation of the analyzer, they do not learn the process of analysis, that is, the chemical analysis of the specimen. To solve this problem, we remodeled a point-of-care automatic analyzer. The analyzer enabled students to observe its actual operation during specimen analysis. We used this analyzer for clinical practice training and obtained information on its effectiveness as a learning tool by means of a questionnaire survey. The questionnaire survey indicated that most of the students agree that the analyzer helped them learn more about the following, aspects of clinical practice: general clinical laboratory medicine (68.5%); method of analysis (57.5%); sampling method (70.0%); and point-of-care tests (52.8%). Above all, 60% of the students became interested in clinical laboratory medicine after their practical experience with the analyzer. The analyzer enables medical students to observe directly the process of biochemical analyses, and is a valuable learning tool for the students.

[A case of advanced gastric cancer with obstructive jaundice due to multiple liver metastasis successfully treated with the following combination therapy of CPT-11 and cisplatin after combination therapy of paclitaxel and TS-1].

A 60-year-old man, who had been admitted to another hospital with complaints of constipation, abdominal fullness and appetite loss, was referred to our hospital for further examination and therapy. The patient was diagnosed as advanced gastric cancer (type-3) with multiple liver metastasis and obstructive jaundice. He was treated with combination therapy of paclitaxel and TS-1 (60 mg/m(2)/day of paclitaxel was iv administered on day 1 and 8, and TS-1 of 80 mg/m(2)/day was orally administered for 2 weeks followed by one drug-free week), and showed a remarkable response. However, because of ascites, elevated serum CEA level and resistance in the liver metastasis and gastric region, we attempted two courses of combination therapy with high-dose CPT-11 and cisplatin (70 mg/m(2)/day of CPT-11 was administered iv on day 1 and 15, and 80 mg/m(2)/day of cisplatin on day 1 followed by two drug-free weeks) which showed a remarkable response. Two courses of combination therapy with low-dose CPT-11 and cisplatin (60 mg/m(2)/day of CPT-11 and 30 mg/m(2)/day of cisplatin were administered iv on day 1 and 15 followed by two drug-free weeks) on an outpatient basis. However, the patient showed resistance to the latter combination therapy, increased ascites due to suspicious peritonitis carcinomatosa and obvious re-growth of the metastatic tumors in the liver. He died on May 23, 2006, about ten months after initial diagnosis. We reported a case of successful treatment of combination chemotherapy for advanced gastric cancer with obstructive jaundice due to progressive multiple metastatic tumors in the liver and obtained comparative long-term survival maintaining high quality of life.

[A case of exacerbation of ulcerative colitis induced by combination therapy with PEG-interferon alpha-2b and ribavirin for chronic hepatitis C].

A 55-year-old man with chronic hepatitis C had diarrhea with bloody stool in July, 2003 and ulcerative colitis was suspected. However, he quickly improved. He was treated with percutaneous radiofrequency ablation therapy for adenomatous hyperplasia in S5 of the liver in December, 2004. After the ablation therapy, he was treated with combination therapy of PEG-interferon alpha-2b and ribavirin for chronic hepatitis C. Because exacerbation of ulcerative colitis appeared 10 weeks after beginning of the treatment for hepatitis C, the combination therapy of PEG-interferon and ribavirin was discontinued. He was treated with mesalazine and steroid therapy for ulcerative colitis, and improved. We report the first case in Japan of the exacerbation of ulcerative colitis induced by the combination therapy of PEG-interferon and ribavirin for chronic hepatitis C.