Hiroki Kajihara

• MD, PhD, Emeritus Professor
• Managing Director at Hiroshima Prefectural Medical Assosiation, Japan

Salivary gland neoplasms are uncommon, and their epidemiology in Japan has not been well described. We conducted a retrospective review of salivary gland tumors registered in the Hiroshima Tumor Tissue Registry over a period of 39 years. The subjects were 5015 cases ranging in age from 6 to 97 (mean, 54.3) years old. The incidence of both benign tu...

Background Reported information on the characteristics of benign bone tumors is disjointed, and the long-term trends in the occurrence of malignant bone tumors by histological type have not been reported in Japan. Our aim was to describe the characteristics of both benign and malignant bone tumors as described in cases registered in the Hiroshima T...

A previously reported autopsy case of eosinophilic coronary periarteritis (ECPA, or isolated eosinophilic coronary periarteritis, IECPA), and an additional six autopsy cases of ECPA are reported. In addition, another four autopsy cases of ECPA reported in the literature are discussed. Fifteen cases of ECPA with spontaneous coronary dissection (hema...

Morphologic change of the myocardium of the dog were observed in oligemic and normovolemic shock produced by Wiggers' standard method. Subendocardial hemorrhages, usually superficial and located mostly in the ventricular aspect of the septum, were remarkable in the normovolemic shock group, but rare in the oligemic shock group. The zonal lesion app...

Motor deficits after spinal cord injury arise from damages to the descending spinal pathways and ventral motoneurons (VMN). In contrast to data on damages to the white matter or the descending spinal pathways, few quantitative data on damages to VMN after injury are available currently. The purpose of this study was to examine quantitatively the te...

To investigate the phenotypes of stromal cells in primary lung carcinomas, we examined the distribution of CD34-positive stromal cells in primary lung carcinomas, with special reference to histological types. In total 26 surgically resected primary lung carcinomas (13 adenocarcinomas, 10 squamous cell carcinomas, 2 large cell carcinomas, and 1 smal...

In this study, the effect of weightlessness on mechanoreceptors in ACL was investigated in rats with hindlimb suspension. The animals used in the present study were 20 Wistar male rats (weight: 278 ± 16 g). The animals were divided into 2 groups: the Suspension group (n=10, suspended for 4 weeks) and Control group (n=10, non-suspended for 4 weeks)....

Immunocompetent cells, such as lymphocytes and macrophages are easily damaged after severe thermal injury. In the present study, we investigated structural changes in splenic lymphocytes in the early period after a full skin thickness burn of 30% of the body surface area in rats. At 2h after thermal injury, numerous B lymphocytes had accumulated in...

Brain infarction was induced in rats by injection of microspheres through the right internal carotid artery, and structural changes in the astrocytes were observed during the early period following the infarction. Necrotic foci, varying in size and shape, were found in the right hemisphere. After immunohistochemical staining for GFAP, GFAP-positive...

In this study we try to clarify sequential changes in Meissner corpuscles after transection of the spinal cord. Meissner corpuscles stained with cholinesterase in the experimental group were already significantly fewer one week after spinal cord transection. The condition of rats in the first week after the operation was regarded as a spinal shock...

Spinal cord cross-over serotoninergic fibers increase when the thoracic spinal cord of a rat is hemisected and the recovery of locomotion is stimulated. The purpose of this study was to examine whether muscular overuse affects this increase in spinal cord cross-over serotoninergic fibers. Forty-four Wister male rats (6 weeks old) were divided into...

Cutaneous branches of radial nerves in patients with lepromatous leprosy (LL) and borderline lepromatous (BL) were studied by light and electron microscopy. Foamy macrophages were found more or less in the nerve fibers of all leprosy patients and distributed in the epineurial, perineurial and endoneurial areas. In the endoneurium, the foamy macroph...

症例は39歳, 女性.微熱, 咳漱を主訴に近医を受診し, 胸部X線写真で異常陰影を指摘されたため, 当院に入院となる.CTおよびMRIでは, 右中間気管支幹内を占拠する径約2cmの腫瘍陰影と末梢側の無気肺像を認め, 気管支鏡下の腫瘍生検では確定診断が得られなかった.気管支内腫瘍の診断のもと, 右中下葉切除術を施行し, 摘出標本では, 中葉気管支原発の境界明瞭な黄白色調の腫瘍を認め, 右中間気管支幹内に突出していた.病理組織学的所見ではmucous gland adenomaと診断された.術後1年半を経過し, 再発を認めていない.

We report a case of adenocarcinoma of the rectum with foci of metaplastic shadow cells. The patient was a 65 year old man with anemia. Macroscopically the tumor was an ordinary rectal cancer. Microscopically, in addition to the features of moderately differentiated adenocarcinoma invading the subserosa, islands of shadow cells in tumor nests were d...

We experienced an interesting case of anterior mediastinal mature treatoma. A 20-year-old woman was admitted to our department with a suspicion of mediastinal tumor found by chest roentgenogram. She had no symptoms but laboratory data showed elevation of serum SCC and CA19-9. Computed tomography and MRI revealed a heterogeneous multi-cystic lesion,...

We report a case of papillary adenocarcinoma of the sigmoid colon with psammoma bodies and intracytoplasmic hyaline globules. The patient was a 59-year-old woman. The tumor showed central ulceration with smooth elevated ridges. Histologically, the tumor was composed of numerous large irregular tubular structures accompanying infolded papillary grow...

Fluosol-DA and FC43 emulsion were developed as red blood cell substitutes. However, these perfluorochemical (PFC)-based compounds are not very promising because of their immunosuppressive effects. Therefore we used these compounds as immunosuppressive agents in guinea pig-to-rat discordant heart xenotransplantations. In rats treated with these comp...

We report a case of hyaline cell-rich chondroid syringoma arising in the skin on the left side of the neck. The tumor was composed exclusively of hyaline cells arranged in a predominantly thick trabecular pattern. Ductal structures of various sizes in the tumor were composed of eosinophilic cuboidal cells showing transition to hyaline cells. Immuno...

A solitary Peutz-Jeghers-type polyp of the rectum in a 64-year-old Japanese man is reported. Barium enema and endoscopic examination revealed a solitary polypoid lesion in the rectum. The polyp was pedunculated, and measured 2 × 1.5 × 1.5 cm. The patient had neither mucocutaneous pigmentation nor a family history of gastrointestinal polyposis. Hist...

Fine structural changes of muscle spindles in the extensor digitorum longus of the gracile axonal dystrophy mutant mouse were studied from 20 to 120 postnatal days. Degenerative nerve endings in muscle spindles were first recognized at 20 postnatal days. The sensory nerve endings were usually swollen with decrease of cell organelles, and the cytopl...

We report a case of ancient schwannoma, which is a rare benign neoplasm of the oral floor and ventricular portion of the tongue. Only two cases have previously been reported in the English literature. The present tumor, measuring 5.5 × 3.0 × 3.0 cm, was the largest of the three. To differentiate ancient schwannoma from schwannoma with malignant tra...

We report a case of a 30-year-old female with a 4-year history of bronchial asthma and recurrent pneumonia accompanying by eosinophilia. She was admitted to our hospital because of a lower abdominal pain, marked eosinophilia, bloody stool, hematuria and arthralgia. Initially, the diagnosis was acute appendicitis and she underwent an appendectomy. S...

The standard wigger's method was used to induce haemorrhagic shock (HS) in anaesthetised dogs by bleeding to a mean arterial pressure (MAP) of 50mmHg for 2 hours and then to 30mmHg for 1 hour followed by reinfusion of the shed blood. Concurrent with this, endotoxin shock (ES) was also induced by intravenous infusion of Escherichia coli endotoxin in...

Effects of naftidrofuryl oxalate (naftidrofuryl) on neurotransmitter, acetylcholine, and amino acid content of brain regions following microsphere-induced cerebral embolism were examined to elucidate its possible therapeutic effects on ischemic brain. Rats received 900 microspheres (48 m in diameter) via the right internal carotid artery, followed...

The authors devised two liquid oxygenator units in which blood is directly oxygenated with oxygenated perfluorocarbon (PFC), a substance harmless to the blood that has a high specific gravity. 1) The droplet-type oxygenator unit is composed of a blood oxygenating chamber and a PFC oxygenating chamber. Blood is oxygenated by the infusion of PFC drop...

A 74-year-old man complained of a cough and left chest pain. Chest X-ray showed marked pleural effusion and a large mass in the left lower lobe, and air bronchograms within the mass were observed by tomography and computed tomography (CT). About 3 months later, the patient died of left atelectasis and pneumonia. Autopsy revealed a localized tumor i...

Changes in plasma haemoglobin levels and morphology of Kupffer cells were studied in rats following lethal thermal injury. Severe haemolysis was observed immediately after thermal injury. The plasma haemoglobin levels rapidly increased to a maximum level 15 min after injury and then rapidly decreased with time. However, the values were still higher...

A 57-year-old man with essential thrombocythemia (ET) developed myelofibrosis, that progressed to a blastic transformation state. The characteristics of the blastic cells were serially studied both morphologically and phenotypically as well as in cell culture. The blastic cells that were first detected in peripheral blood had features of myeloid st...

The morphologic, immunologic, genotypic and functional properties of peripheral blood and bone marrow cells or cultured cells from four patients with a clinically aggressive non‐T, non‐B natural killer cell leukaemia/lymphoma (ANKL/L) are described. The leukaemic cells possessed medium to large granules in the cytoplasm, antigens against CD38, CD2,...

A 33 year old woman with mental deficiency, retinitis pigmentosa, obesity, and parental consanguinity (heredity) was diagnosed as having Laurence-Moon-Biedl syndrome. She also had diabetes mellitus, slight hepatic dysfunction, and hepatomegaly. Liver biopsy showed perilobular fibrosis and bile duct proliferation with cystic dilatation; these findin...

The morphologic, immunologic, genotypic, and functional properties of peripheral blood and bone marrow cells or cultured cells from two patients with a clinically aggressive non T, non B natural killer cell lymphoma/leukemia (ANKL/L) were described. The leukemic cells possessed medium to large granules in the cytoplasm, antigens against CD 38, CD 2...

In this study, pretreatment peripheral and/or bone marrow blasts from 12 patients with acute unclassifiable leukemia (AUL) expressing the myeloid-related cell-surface antigen (CD 11) were isolated for further analysis. Despite a lack of myeloperoxidase (MPO) activity, 1 patient's blasts contained cytoplasmic Auer rods. The circulating blasts from a...

Five-week-old male Crj: CD (SD) rats were treated with 10% sodium chloride after a total dose of 20 Gy of X-ray administered to the gastric region in two equal fractions separated by 3 days. After treatments, the animals were sacrificed seqentially and analyzed quantitatively on the medial and small arteries in the stomach. In the early phase after...

In this report, we have described three cases of acute megakaryoblastic leukemia (AMKL) which were demonstrated by the presence of megakaryocyte-platelet-related cell-surface antigens detected by utilizing flow cytometry and monoclonal antibodies in addition to both PPO activity which was shown by ultrastructural cytochemistry and emergence of diff...

The morphology, immunologic and functional properties of peripheral blood and bone marrow cells or cultured cells from 2 patients with clinically aggressive non-T, non-B lymphoma/leukemia are described. The leukemic cells possessed medium to large granules in the cytoplasm, antigens against CD38, CD2, CD25, OKIa1, CD16, TA-1, CD9, CD24 and NKH-1 (N...

Five-week-old male Crj:CD (SD) rats were treated with excess sodium chloride after abdominal X-irradiation. The gastric regions of the rats were irradiated with a total dose of 20 Gy given in two equal fractions separated by 3 days. After X-irradiation, animals were fed a diet containing 10% sodium chloride. Red blood cell anemia appeared 22 weeks...

Structural changes of the white pulp of the spleen were investigated in dogs subjected to hemorrhagic shock. At 1 h after hemorrhage (early impending stage), hydropic changes of the germinal center cells were observed by electron microscopy, while no remarkable change could be found by light microscopy. At 2 h after hemorrhage (end of impending sta...

An autopsy case of idiopathic dilated cardiomyopathy with abnormal proliferation of mitochondria in the myocardial cells is reported. The case is that of a 39-year-old male with congestive heart failure. The heart was 700 g and showed marked dilatation of all cardiac chambers with myocardial fibrosis of the left ventricular myocardium and intervent...

Pseudoxanthoma elasticum (PXE)および眼底の網膜色素線条に冠動脈異常を合併したGronblad-Strandberg症候群の1例を報告した.症例は19才,女性. 16才より難治性の前頚部皮疹が出現し,皮膚生検にて弾性線維の変性,膨化,断裂, Ca沈着を認め, PXEと診断した.心電図ではV1～3にQS patternを示し,左室造影にて前側壁および心尖部の壁運動低下を認めた.冠動脈造影にて左冠動脈のび漫性狭窄,壁不整,蛇行および後側壁枝の完全閉塞を示し,右冠動脈遠位部の壁不整,蛇行を認めた.右室心筋生検所見では心筋細胞内にグリコーゲン顆粒の沈着が目立つたが,著明な変化は認められず,冠動脈病変は比較的大型の冠動脈の器質的変化によると考えられた.

Changes of secretory activity and structure of the adrenal cortex were observed in dogs subjected to hemorrhagic shock. Blood cortisol and aldosterone levels were rapidly increased after hemorrhage. The cortisol level reached a maximum value about 5 times that of normal 1 h after hemorrhage, while aldosterone levels attained maximum levels showing...

Hyaline inclusion bodies appeared in hepatocytes of acutely congested livers produced by prolonged extracorporeal circulation. The inclusions were positive by PAS, PTAH and Ziehl-Neelsen staining and were colored light green to green by Masson's trichrome staining. In methylene blue-stained sections, they were divided into two groups, pale to light...

Purpose: It was the purpose of this present study to determine the biocompatibility, especially antithrombogenic and antihemolytic properties, of vinyl chloride and polyurethane, which are used as material for artificial hearts.Methods: An LV-Ao hypass-pump driven by air was installed in rabbits between the apex of the left ventricle and the abdomi...

Small granule chromaffin cells (SGC cells) were identified in the adrenal medulla of adult dogs. They were small in size and usually showed a high nucleo-cytoplasmic ratio. Cytoplasmic projections were occasionally observed in some of these cells. They contained a variable number of small secretory granules with diameters ranging from 70 to 300 nm,...

Chronic toxicity of 2-(2-furyl)-3-(5-nitro-2-furyl)acrylamide (AF-2), which had been widely used in Japan as a food additive, was studied in both sexes of ICR/JCL mice by feeding a diet containing AF-2 in a concentration of 0.4% or 0.08%. The experiments confirmed its definite carcinogenicity in the forestomach, with dose dependency; more than 70%...

The effects of the cardiopulmonary bypass circulation on the cardiac muscle cells were studied electron microscopically. Subendocardial hemorrhage was commonly recognized in both ventricles. However, it appeared earlier and more severely in the right ventricle than in the left ventricle. Clear flocculent areas containing numerous filamentous struct...

In an attempt to improve the treatment of acute myeloid leukemia of humans, the hematological characteristics of two myeloid leukemias of W/Fu rats L1504 and L1005, both of which were induced by the oral administration of N-nitrosobutyl-urea, 1-urea, were investigated as possible new animal model systems. L1504 was rapidly growing, with a negative...

Blood catcholamine levels and ultrastructural changes in adrenal medullary cells were followed during the course of oligemic and normovolemic shock in dogs. Blood adrenaline concentration rose promptly after hemorrhage, reaching a maximum that was 10-fold greater than normal during the early period of hemorrhagic hypotension. Thereafter, adrenaline...

Wistar rats were injected intravenously with cod liver oil emulsion. The phagocytosis of these lipids by the Kupffer cells as well as the formation of lipid-containing lysosomes were studied electron microscopically within a period of 5 min to 12 hrs. The emulsified lipids are incorporated into the cytoplasm by membrane-vesiculation. The lipid-cont...

Wistar rats were injected intravenously with cod liver oil emulsion. The phagocytosis of these lipids by the Kupffer cells as well as the formation of lipid-containing lysosomes were studied electron microscopically within a period of 5 min to 12 hrs. The emulsified lipids are incorporated into the cytoplasm by membrane-vesiculation. The lipid-con...

Wistar rats were injected intravenously with cod liver oil emulsion. The lipid droplets were phagocytized by Kupffer cells and stored in lysosomes. The transformation of these lipid-containing lysosomes into ceroid pigment granules was studied electron-microscopically and cytochemically for a period of 12 weeks after the injection. The lipid dropl...

Wistar rats were injected intravenously with cod liver oil emulsion. The lipid droplets ere phagocytized by Kupffer cells and stored in lysosomes. The transformation of these lipid-containing lysosomes into ceroid pigment granules was studied electron-microscopically and cytochemically for a period of 12 weeks after the injection. The lipid droplet...

Hypertrophied muscle cells of the right ventricles obtained from 12 patients with congential malformation of the heart (VSD, TF, A-V canal and AASV) have been studied by electron microscope. The process of hypertrophy of cardiac muscle cells was almost identical among these cardiac diseases. Slightly hypertrophied muscle cells are characterized by...

A comparative study of chemical and radiation leukemogenesis was carried out in mice and rats. The results obtained from this study indicate that there seems to be a common mechanism for both chemical and radiation leukemogenesis in mice. In both instances, the direct inducer is Gross type virus; and carcinogenic chemicals or radiation merely provi...

The right ventricular myocardium of the cor pulmonare in the rat induced by subcutaneous single injection of monocrotallne has been studied by electron microscope. The hypertrophy and wearing of myocardium was sequentially categorized into (1) preparatory stage, (2) hypertrophied stage, and (3) damaged stage. Slightly enlarged and injured mitochond...

先行研究によれば, ラットの胸髄が半切されると腰髄レベルでは脊髄交叉性にセロトニン線維が増加し, この影響により歩行運動機能の回復が促進されると考えられている。本研究の目的は, 脊髄交叉性のセロトニン線維の増加が半切側下肢を過用させることで影響されるかどうかを免疫組織化学的に検討することである。実験動物は6週齢のウィスター系雄ラットで, 胸髄右側を半切した31匹のうち18匹はそのまま回復させ, 13匹は半切側下肢を過用させる目的で対側坐骨神経を切断した。結果, 半切側の腰髄前角に分布するセロトニン線維は, 半切1週後は著名に減少したが, 2, 3週後には増加・再分布が認められ, これは半切側下肢を過用させた場合が著しかった。したがって, 脊髄交叉性のセロトニン線維の増加は, 半切側下肢の過用...

骨格筋再生過程におけるミオシン重鎖(MHC)アイソフォーム発現とmyogenin,MyoDタンパクの発現様式との関連性を検討するために,塩酸ブピバカインを用いてマウスヒラメ筋損傷モデルを作成し,損傷筋の再生過程を組織形態学的に確認すると同時に,再生各段階におけるMHCアイソフォームと,myogeninおよびMyoDタンパク発現を経時的に検索した.本研究における筋損傷は塩酸ブピバカインをマウス(C57BL/10SnSlc)のヒラメ筋に注入することで作成した.組織学的には,塩酸ブピバカイン投与後3日目で筋線維はほとんど消失し,処置後6日目で中心核を有する再生筋線維がかなり出現し,処置後28日目では対照群のものと同程度まで回復した.生化学的分析では,対照群ヒラメ筋はMHCⅠ(34.3±1.7%)と...

右心不全に伴って,速筋および遅筋の筋小胞体Ca2+取り込み能が減少するという仮説を検証した.右心不全は,モノクロタリン(30 ㎎/㎏)を投与することにより引き起こし,投与後4週で,長指伸筋およびヒラメ筋を両後肢から採取した.筋の疲労耐性は,連続的な強縮刺激を行うことにより測定した.長指伸筋では刺激開始1分後,ヒラメ筋では4分後の張力を測定し,初期値に対するそれらの割合を疲労の指標とした.長指伸筋およびヒラメ筋の疲労耐性は,右心不全群で有意に低下した.筋小胞体Ca2+取り込み速度は,Indo-Ⅰを付加したホモジネートで測定した.その結果,Ca2+取り込み速度は,長指伸筋で25.4%(p<0.01),ヒラメ筋で30.4%(p<0.05)低下した.このCa2+取り込み速度の低下は,筋小胞体Ca2+...

様々な大きさのジストロフィンアイソフォーム(427kDa, 260kDa, 140kDa, 116kDa, 71-75kDa)が広く体内に存在していることはよく知られている.中枢神経系においては71-75kDaのDp71が著明に多く,毛細血管の内皮の基底膜に接しているアストロサイトの細胞質に局在することが報告されている.しかしながらDp71の機能についてはよくわかっていないことが多い.そこで今回,脳組織におけるDp71の役割を調べるために,コントロールマウス(wild-typeマウス)およびデュシャンヌ型筋ジストロフィーモデル動物であるmdxマウスを用いて実験的脳梗塞を作成し,その治癒過程を形態学的に観察した.また,GFAPおよびDp71に関して生化学的に分析をおこなった.HE染色およびGF...

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