The number of the cases of orthodox (classical) infections has decreased, but the number of the cases of opportunistic infection and imported infections is now increasing. Rapid diagnosis, effective treatment and prophylaxis of these changing infectious diseases are very important at present. Emerging infectious disease is defined as a novel infectious disease with newly isolated causative pathogen which causes a very important problem from an aspect of public health. Severe acute respiratory syndrome (SARS) which outbreak has been reported in mainly China, Hong Kong and Taiwan is the newest emerging infectious disease. Epidemiology, causative pathogen, clinical findings and prophylaxis of SARS are summarized.

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Severe acute respiratory syndrome (SARS) is a new infectious disease caused with a newly “emerging virus” named as SARS-coronavirus (SARS-CoV). The first index case of SARS was reported in Hong Kong on Feb 22, 2003. In April 9, 970 cases of SARS patients including 241 cases of medical doctor, medical students, nurses, and health care workers have been identified in all over Hong Kong, with above 5% of mortality. Therefore, this disease has highly infectious ability. The outbreak of SARS in Hong Kong has prompted by “The Hong Kong Hospital Authority Working Group on SARS” collaborated with The Chinese University of Hong Kong and The University of Hong Kong, to implement a series of public health measurement and hospital policies for early diagnose, treatment and management of SARS patients. For the purpose of establishing the SARS management system in Kyorin University Hospital, the author visited Hong Kong University Queen Mary Hospital (QMH) for inspecting pathogenesis, hospital policy and hospital management against SARS in the beginning of April 2003. In this paper, we discuss about the pathogenesis of SARS, the precautions and hospital management for SARS patients.
[Clinical Observation] All the SARS patients in Hong Kong presented with over 38°C of pyrexia, and most presented with chillness, malaise, dry cough, headache and any other “flu-like” symptoms. Lymphopenia was one of the typical testing data supported to diagnose SARS. In chest roentgenogram, early progressive ground grass opacity had shown from lower lung fields to upper fields. The poor prognosis of SARS patients were shown to be due to lymphocyte-induced diffuse alveolar damage in their lung pathological findings. It is thinkable that high dose of steroids therapy might modulate against this hyper immune response in SARS-CoV infected lung.
[Hospital Policy and Precautions from SARS in QMH] In QMH, thus in anticipation of the increase admission and the possibility of a sudden influx due to community outbreak of SARS, the “QMH-SARS core team” shall bottom-up their contingency plan to provide 300 of SARS cohorted beds, 25 of cohorted negative pressured ICU beds, and supported any other clinical departments and hospitals for back-up beds. All the wards of QMH were not open to visitors. Everyone within the hospital, including the patients admitted in other wards and/or outcome patients have to put on surgical mask. All the staffs should be observed in controlling spread of droplet/contact infection, based on standard precautions technique. The QMH SARS core team established these kinds of hospital policy and the systems for SARS treatment, only in 2 weeks.
[Hospital policy for SARS treatment in Kyorin University Hospital] Kyorin University Hospital doesn't have negative pressured ward for admitted infectious patients, in April 2003. Also, it is impossible to lead the SARS patient for ward without contact with other patients, supposing preparation of urgent negative pressured ward in our hospital. Therefore, We decide to care chiefly outcome SARS patients but not case with hospitalized SARS. All of the hospital policy, precaution methods are based on the QMH's one.

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Mutation sites in the p53 gene were analyzed with a methylchoranthrene-induced transplantable mouse tumor cell (Meth A cell) to clarify the relationship between the sequential mutation of the suppressor oncogene and the malignancy of the tumor cell. The sequence in p53 was analyzed with DNA prepared from transplanted tumor cells in BALB/c mice by the direct sequencing technique.
The DNA was amplified by the regular PCR method and analyzed by the Sanger dideoxy termination method. Sequences of 1, 450 bases out of a total 2, 189 bases in the exon (66.2%), and sequences of 586 bases in a total of 1, 173 bases (50%) in the cording region of p53 gene were analyzed. Analytical results revealed that 33 sites of transition, 2 sites of insertion of the nucleotide, and 12 points of mutation in the codon exist in the region examined. The highest rate of mutation was observed in G (3.0%), the lowest rate was in T (1.1%). The appearance rate of the nucleotide at the mutation site was 4.5% for T, the highest, and 0.6% for G, the lowest. 8 sites of mutational changes in an amino acid, which were postulated from the change in the codon, were concentrately accumulated in exon 5 of the gene. Formation of a terminator codon (TGA) and a change in the Zn-finger ligand amino acid in the DNA binding domain were observed in this region of the p53 molecule. These mutational changes in the genomic structure appear to mislead the cell to malignant development.

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Glutamate has been suggested to be a mitochondria-derived metabolic factor to augment insulin secretion in pancreatic beta-cells, but the mechanism of augmentation is not clarified. In the present study, to analyze the mechanism responsible for the insulin secretion, we investigated the effect of glutamate on insulin secretory capacity, proinsulin processing and KATP channel activities using rat pancreatic islets and MIN6 cells. In the presence of stimulatory of glucose (5.5mM), 5mM dimethyl-glutamate, a membrane permeable analog of glutamate, potentiated insulin release via ATP-sensitive K⁺ channel (KATP channel)-dependent and -independent pathways in rat pancreatic islets and MIN 6 cells. The stimulatory effect of dimethyl-glutamate was most prominent under 8.3mM glucose. In pulse-chase studies after labeling with [³H] leucine, 5mM dimethyl-glutamate failed to affect the conversion rate from proinsulin to insulin even in the presence of 8.3mM glucose. By contrast, 100mM 2, 4-dinitorophenol, a metabolic uncoupler, delayed the conversion significantly. In the patch-clamp studies, dimethyl-glutamate reversibly suppressed KATP channel activities in cell-attached mode. On the other hand, L-glutamate did not influence KATP channels in inside-out mode.
These results indicated that glutamate potentiates insulin secretion through KATP channel-independent pathway without promoting proinsulin processing into insulin in the secretory granules. In addition, it inhibits KATP channel activities to enhance insulin exocytosis by generating metabolic signals, possibly distinct from ATP.

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The bromocriptine-rebound method of ovarian stimulation for in vitro fertilization improves oocyte maturation, embryonic development, and pregnancy rates.
We examined whether this method enhances endometrial receptivity.
The method resembles the long protocol using a gonadotropin-releasing hormone (GnRH) agonist and human menopausal gonadotropin, except that 2.5mg of bromocriptine is administered daily from day 3 of the previous cycle until 7 days before initiating menopausal gonadotropin administration. Only transfers with two or more superior-quality embryos were analyzed. Successfully initiated and ongoing pregnancy rates per transfer were significantly higher with the bromocriptine-rebound method (43% and 39%, respectively) than with the long protocol (27% and 20%). Serum prolactin (PRL) and progesterone concentrations on day 10 after oocy-te pickup were higher with the bromocriptine-rebound method.
We also analyzed the relationships between PRL in endometrial secretions in the late luteal-phase of a spontaneous cycle and subsequent in vitro fertilization outcomes. When the local PRL was over 13ng/mL, implantation was achieved with the long protocol but not with the bromocriptine-rebound method; in contrast, when the local PRL was 13ng/mL or less, all implantations occurred with the bromocriptine-rebound method but none with the long protocol. Local PRL on day 14 after oocyte pick up was significantly higher with the bromocriptine-rebound method than with the long protocol. Mouse blastocysts spread on culture dishes was significantly stimulated by PRL supplementation of the medium. Thus, the bromocriptine-rebound method improves the endometrial receptivity probably by increasing local PRL in endometrial secretions.

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