実験コレラ発症に関連する幼若マウス腸管の特徴

In the pathogenesis of infectious diseases, a certain host factor should play a significant role as well as a pathogenic microorganism. Cholera, an infection with Vibrio cholerae, is not an exception. The clinical manifestation of cholera should be influenced by a certain condition of the host infected with Vibrio cholerae. In the experimental cholera of mice by oral challenge with Vibrio cholerae which has been developed by Ujiie and others, the incidence of the disease is closely related to the age of mice; only infantile mice younger than one week old of age are susceptible to oral challenge with Vibrio cholerae, and in mice older than one month, neither symptom nor multiplication of Vibrio cholerae in the intestine is seen. Therefore, it is understood that the infancy of mice should be one of the host factors as far as the experimental cholera in mice is concerned. It is presumed that characteristics of the infancy of mice may consist of uncompleted intestinal flora, deficiency of digestive enzymes, simplicity of intestinal content, particular immunological condition, abnormal absorptive ability of the intestine, etc. In this study, the morphological structure, histochemical behavior and function of the intestinal mucosa were investigated to compare the differences between infantile and adolescent mice. The characteristics of the infancy were as follows. 1). The surface of villi was lacking in enzyme layer. 2). The intercellular space in the epithelium was wide and conjunction between the cells is lax except apical region. 3). There were a lot of vesicles and vacuoles of various size or phagosomes and pinocytotic indentations in the upper part of the absorptive cells. 4). A large number of phagolysosomes were found in the middle part of the cytoplasm. 5). The plasma membrane of microvilli was lacking in trilaminal structure. 6). Polysaccharides and alkaline phosphatase were not or poorly found in the brush border. 7). Epithelial cells ingest protein (ferritin) without decomposition. The above mentioned characteristics which were found in the infantile mice suggest that toxin or toxin-like substances produced in the intestine by multiplying Vibrio cholerae will be able to be absorbed through the intestinal wall. So far, no exact knowledge on the host factor in human cholera has been obtained. However, it can be presumed that some of the factors which were indicated by the present study may be a homologous condition in the pathogeny of human cholera.感染症において,病原体が病因として決定的な役割を演ずるのは当然であるが,同時に宿主側の条件が発症機序に大きく関与する.コレラについても例外ではなく,感染個体の発症如何は宿主生体側の条件に左右されるとが大きい.氏家らが開発した幼若マウスにおける実験コレラでは,コレラ菌経口感染による発症率が,生後日数と確実に相関する.すなわち,生後1週間頃を境として発症率が著明に異なり,生後1ケ月以後のものでは全く発症が認められない.この実験コレラの成績に関しては,マウスの幼若性を発症のための宿主側条件の一つとして理解することが出来る.実験コレラ発症要因としての幼若性を分析すれば,腸内細菌叢の未完成,消化酵素の欠如,腸内容の単純性さらに免疫の異常などとともに腸粘膜細胞の構造ならびに機能の未熟さを挙げることが出きよう.この研究においては,腸粘膜の構造および機能を,生后1週間前後ならびに1カ月前後のマウスについて比較し,幼若性という特質を両者の相異からみいだそうと試みた.幼若マウスに認められた特徴は次のようであった.1,絨毛上皮の表面はenzyme layerを欠いている.2,絨毛上皮層の細胞間隙が広く,細胞間の結合が弱い.3,細胞質内には大小多数の空胞,液胞あるいはPhagosomeを有し,同時に多数のpinocytotic identationを認める.4.細胞質内には極めて多数のPhagolysosomeが存在する.5.Microvilliにおいては,限界膜の三層構造が不明瞭である.6.刷子縁における多糖類の存在およびアルカリフォスファターゼの活性は極めて乏しい.7.上皮細胞は蛋白質(フェリチン)を未消化(原形)のままとり込む.以上のように,幼若マウスが示した腸膜粘の構造ならびに機能上の特異性は,腸管内においてコレラ菌が増殖した場合,その毒素または毒素様物質が容易に吸収される可能性を示している.ヒトにおけるコレラ発症の生体側要因は今日全く不明であるが,ここに幼若性を分析して得たいくつかの条件の個々あるいはそのいくつかが重さなり合って,ヒトのコレラ発症に相似の条件を呈供することもありうると思われる

Characterization of Bombyx mori Nucleopolyhedrovirus orf68 Gene That Encodes a Novel Structural Protein of Budded Virus

AbstractAll lepidopteran baculovirus genomes sequenced to date encode a homolog of the Bombyx mori nucleopolyhedrovirus (BmNPV) orf68 gene, suggesting that it performs an important role in the virus life cycle. In this article we describe the characterization of BmNPV orf68 gene. Northern and Western analyses demonstrated that orf68 gene was expressed as a late gene and encoded a structural protein of budded virus (BV). Immunohistochemical analysis by confocal microscopy showed that ORF68 protein was localized mainly in the nucleus of infected cells. To examine the function of orf68 gene, we constructed orf68 deletion mutant (BmD68) and characterized it in BmN cells and larvae of B. mori. BV production was delayed in BmD68-infected cells. The larval bioassays also demonstrated that deletion of orf68 did not reduce the infectivity, but mutant virus took 70 h longer to kill the host than wild-type BmNPV. In addition, dot-blot analysis showed viral DNA accumulated more slowly in mutant infected cells. Further examination suggested that BmD68 was less efficient in entry and budding from cells, although it seemed to possess normal attachment ability. These results suggest that ORF68 is a BV-associated protein involved in secondary infection from cell-to-cell

コレラの治療におけるクロラムフェニコールの研究 : 第1編

In the recent the investigation of the pathophysiology and pathogenesis on cholera has made remarkable progress. However, the mechanism of diarrhea has not been completely clarified. It has been well known that antibiotics is considerably effective for treatment of cholera patient. Some problems, however, for instance, regarding the mechanism of effectiveness or a reasonable route of treatment still remain unsolved. In the present study, CP given orally and intravenously on cholera patients was hourly determined by bioassay as an approach to clarify the mechanism of antibiotics and also comprehension of pathophysiology of cholera. Twenty-seven cholera cases, confirmed bacteriologically, admitted at the San Lazaro Hospital in Manila during the period from August through November 1968 were investigated for this study. Fourteen cases were intravenously treated with CP, and thirteen cases orally. CP was determined in blood and stool consecutively. In the majority of cases treated by mouth, CP did not appear in stool and also was not proven in blood in half of cases; in others the blood level of CP was lower or elevated later than normal. On the contrary, in most cases treated with intravenous CP, higher concentration of CP in stool than in blood was proven; some of them showed twice higher concentration in stool than in blood. The number of vibrios in stool was inversely related to the concentration of CP in stool; namely, the majority of cases treated orally showed no reduce of vibrios, while marked decrease of the number was found in most cases with intravenous CP. As, in the study, CP determination was done only by bioassay not by chemical assay, the problem whether CP may be inactivated remains unsolved. The comparative study of different preparation of CP has not been accomplished. These questions will be investigated in our further studies. It has been suggested that the peculiar distribution of CP may be correlated to particular pathophysiological condition of cholera. In the therapeutic point of view, it has been noticed that intravenous treatment indicated more accurate effectiveness for discontinuing excretion of vibrios in stool than oral treatment, as far as the cases with severe diarrhea are concerned.コレラに関してその病態生理並びに発症機序に関する研究は近年著しく進歩したが,下痢の発症機序に関しては必ずしも全貌が明らかにされていない.また抗生物質がコレラの治療に著明な効果を示すことは一般に認められているがその作用機序に関しては不明の点が残されておりかつ薬剤の投与方法に関する疑問もある.こうした問題点の解決の一っのアプローチとしてクロラムフェニコールをコレラ患者に経口的及び経静脈的に与えその血液並びに便中における時間的消長を検討することによって抗生物質の作用機転およびコレラの特異な病態生理を理解しようと試みた.患者は1968年8月から11月まで,マニラのサン・ラザロ病院に入院し,細菌学的にエルトールコレラと診断された27名を選んだ.そのうち14名は静脈内に,13名は経口的にクロラムフェニコ―ルを与え血中並びに便中のクロラムェフニコールの出現および消長を時間的に追究した.その結果,経口的に与えた13例のうち大半の例においてはクロラムフェニコールは便中に出現することなく,血中濃度は半数は全く上昇せず他は正常よりも遅延しあるいは低濃度に証明されたにすぎなかった.静脈内に投与した14例については大多数において投与2時間后に血中よりも高濃度に便中への出現がみられ,中には血中濃度の2倍に達するものもあった.便中のコレラ菌数は便中のクロラムフェニコール濃度に逆比例した消長がみられた。即ち経口投与例の大多数においては菌数の減少は殆どみられなかったが静注例ではその大多数においてコレラ菌数の著明な減少がみられた.以上の観察例の中で,クロラムフェニコールの定量は生物学的方法にのみ頼ったためにその不活性化という点に問題を残している.また静注したものと経口的に与えたものではクロラムフェニコールの剤形が異なり,腸管内における溶解度その他について更に検討すべき余地がある.しかし全般的にみて経口的に投与されたクロラムフェニコールが血中に出現せず静注したものが高濃度に便中に出現したという事実はコレラの下痢あるいは腸内に大量に貯留する液体の成因についていろいろな意味の示唆を含んでいる.また抗生剤療法における排菌に対しては,急性期のコレラに関する限り静脈内投与が経口投与に比較してより適確な効果を示すことが実証された

ソンネ赤痢菌長期保菌者の一例

It has been known that patients with the bacillary dysentery may continue to excrete the bacilli in convalescence and there are not a few healthy carriers without any manifestation of clinical sign. The duration of excretion of bacilli in both convalescent and healthy carriers is generally within a few weeks. A very small proportion of carriers continues to excrete the bacilli for long time. However, even in cases of which stool cultures have been repeatedly positive for the same type of Shigella, it would be difficult to decide a longterm carrier or reinfection. The case reported here was designated as carrier of Shigella sonnei six times for about three years and half since he recovered from the bacillary dysentery. The strains isolated from the case belonged to Shigella sonnei I of which Colicin type was 6, and they were sensitive to antibiotics as Chloramphenicol, Tetracycline and Streptomycin. Regarding the present situation that all strains of Shigella isolated in Nagasaki prefecture are highly resistant to these antibiotics, the sensitivity pattern of these strains could be considered as a characteristic marker, so that it could be able to exclude a possibility to have been reinfected. Some particular investigations as the roentgenographic examinations of the digestive tractus and gallbladder, sigmoidoscopy, rectal biopsy, bile extraction by duodenal intubation etc. were carried out in order to clarify the state of carrier in this case. However,the results were negative so that it could be unable to realize how do the bacilli harbour in the body of the carrier.赤痢患者が症状消退後もある期間排菌をつづける者のあること,なんらの臨床症状のみられない健康保菌者が近年特に増加していることは,一般に認められている.しかし,保菌期間が年余にわたる長期例の報告は少ないし,またそのような例について,再感染が否かを判断する資料が見当らないのが常である.ここに報告する例は,1944年8月生れの青年であって,1965年3月ソンネ菌赤痢に罹患,隔離入院させられたが,抗生剤治療により順調に治癒退院した.本人は某乳業会社に勤務していたために,毎年食品ならびに接客業者のための定期検便をうけた.その結果,1965年6月から1968年11月までの的3年半の期間に,6回にわたって,ソンネ菌が便中に証明された.菌はShigella sonnei I,コリシン型6,クロラムフェニコール・テトラサイクリン・ストレプトマイシン感受性であった.長崎地区における赤痢菌特にソンネ菌の薬剤感受性は最近の5年間に著しく変化し,1962年以来分離されるソンネ菌を主体とする赤痢菌は悉くC. T. Sに高度の耐性を示すもののみとなった.この例は,当時約半数は感受性があったソンネ菌に感染,その菌が3年有半にわたって体内に生残していたと推定される.赤痢菌がこのように長期間保菌される場合,腸内のいづれかの個処に生残しているものか,あるいは胆嚢をチフス保菌者のように棲息場所に撰んでいるのか,を知るために,各種X線検査,十二指腸ゾンデによる胆汁採取,直腸鏡検査,直腸生検などを行なったが,菌の存在場所を確認することはできなかった.患者の自家菌ならびに保存ソンネ菌に対する血中抗体の上昇は認められなかった.この菌の病原性について,北里研究所合田朗博士が行なったウサギ小腸ループを用いる実験によれば, 一般の赤痢菌と同様に,ループ内接種後膿血を混じた漿液の貯溜によりループの著明な腫脹がみられている

Parasitic Pathogens Associated with Diarrhoea in Mombasa, Kenya

A microscopic examination of a faecal specimens was designed to identify the enteropathogenic parasites in the diarrhoeal stool specimens in which neither enteropathogenic bacteria nor rotavirus was isolated in Caost Provincial General Hospital, Mombasa, Kenya. The parasites incriminated as causes of diarrhoea were Entamoeba histolytica, Giardia lamblia, Trichuris trichiura, hookworm and Ascaris lumbricoides. The cysts and ova of these parasites, however, were present with equal frequency in diarrhoeal, semi-formed and formed stool specimens, except the trophozoites of E. histolytica. The role of parasites in causation of diarrhoea is difficult to evaluate by the routine stool examination for parasites

マウスの実験コレラ : I 経口感染に関する第1報

The oral infection in mice, strain ICR, was carried out with E1 Tor vibrio, strain V86 and following results were obtained. The multiplication of vibrios, accumulation of fluid in the intestine-especially in the cecum-, diarrhea and death were observed only in the suckling mice younger than about 10 days old. And the multiplication of vibrios in upper part of the small intestine was observed to be less than that in lower part of the small intestine. In 15-day-old mice, only slight multiplication of vibrios without death was observed, however in 30-day-old mice, viable organisms of the challenged vibrios could not be isolated from intestinal samples even at 3 hours and within 3 days after challenge.マウス(ICR株)を用いてェルトール菌(V86株)による感染実験を行い,次のような結果を得た.生後10日以下の乳のみマウスにおいてのみ,感染菌の増殖,腸管内特に盲腸に液体の貯溜がみられ,また下痢や死亡がみられた.腸管内における感染菌の増殖は小腸上部と下部では,下部に著明である結果を得た.生後15日マウスでは感染菌の増殖が著明でなく,死亡はみらわなかった.生後30日マウスでは,感染菌は感染後3時間ですでにみられず,その後も菌増殖はみとめられなかった

The SNP rs6508974 in AXL is a functional polymorphism and a promising biomarker for gefitinib treatment

Somatic mutations in epidermal growth factor receptor (EGFR) found in lung adenocarcinomas are used as biomarkers for the treatment with EGFR-tyrosine kinase inhibitors, including gefitinib. The bypass tracks with amplification of AXL is one of the mechanisms underlying the resistance to gefitinib. We, therefore, carried out a candidate gene approach method to identify AXL polymorphisms associated with the effectiveness of gefitinib. EGFR mutations were first dentified by mutantenriched PCR-restriction fragment length polymorphism (RFLP), and then 2 tag single nucleotide olymorphisms (SNPs) of AXL were examined by PCR-RFLP in 62 Japanese patients with advanced lung adenocarcinoma and treated with gefitinib in two general hospitals in Nagasaki. Subsequently, the association of EFGR mutations and the AXL polymorphism with the effectiveness of gefitinib was examined in these patients. We next examined the effect of the AXL polymorphism on the expression and function of this gene. It is worthy of note that EGFR mutations and the AXL polymorphism rs6508974 independently contributed to the effectiveness of gefitinib, and the polymorphism was proved to be a possible biomarker for selecting non-responders and responders to gefitinib treatment even in the absence of EGFR mutations. Furthermore, this SNP increased the transcriptional activity of the AXL transcript variant 3, one of the three AXL transcript variants, which to some extent increased the epithelial-mesenchymal transition in cancer cells. Taken together, AXL is one of the genes that determine the effectiveness of gefitinib and a biomarker for selecting non-responders and responders among lung adenocarcinoma patients with no EGFR mutations, suggesting that rs6508974 in AXL might be a functional SNP in lung denocarcinoma

Evaluation of FilmArray respiratory panel multiplex polymerase chain reaction assay for detection of pathogens in adult outpatients with acute respiratory tract infection

Although viruses are the major pathogen that causes upper respiratory tract infection (URTI) and acute bronchitis, antibiotics have been prescribed. This was a prospective observational study in influenza epidemics that enrolled adult outpatients who visited a hospital with respiratory tract infection symptoms. In this study, we evaluated the usefulness of FilmArray respiratory panel (RP). Fifty patients were enrolled. FilmArray RP detected the pathogens in 28 patients. The common pathogens were influenza virus (n = 14), respiratory syncytial virus (n = 6), and human rhinovirus (n = 6). Of the 14 patients with influenza virus, 6 were negative for the antigen test. The physicians diagnosed and treated the patients without the result of FilmArray in this study. Of the patients with positive FilmArray RP, 9 were treated with antibiotics; however, bacteria were detected in only 3 patients. By implementing FilmArray RP, URTI and acute bronchitis would be precisely diagnosed, and inappropriate use of antibiotics can be reduced