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Biomedical subjects

M Hashimoto

Publications and source records attributed to M Hashimoto.

At least 91 records · Page 5Linked to original sources

Significant expression of functional human type 1 mitochondrial ADP/ATP carrier in yeast mitochondria.

As a first step to characterize the unknown functional properties of the human mitochondrial ADP/ATP carrier (AAC), we tried to express human type 1 AAC (hAAC1) in Saccharomyces cerevisiae. Expression of hAAC1 in yeast mitochondrial membrane was very low, although its transcript level was high. Its expression was improved greatly by replacement of its N-terminal region with the corresponding region of yeast type 2 AAC (yAAC2), as observed with the bovine type 1 AAC (bAAC1). This chimeric hAAC1 showed similar ADP transport activity to that of chimeric bAAC1, corresponding to the transport activity of bAAC1 in bovine heart mitochondria. These results suggested that the N-terminal region of yAAC2 is important for expression of the mammalian carriers in yeast mitochondria. Using the present expression system, studies on the functional properties of the human AAC isoforms in relation to their structures are now possible.

Animals↗

Recent epidemiological status of canine viral enteric infections and Giardia infection in Japan.

Epidemiology of canine enteric infections was studied. Rectal swabs collected from 95 dogs presented at animal hospitals during a period from January to June of 2000 were examined for enteric pathogens, including viruses and Giardia lamblia (G. lamblia). Most frequently detected in both diarrheal and normal feces were canine coronavirus (55.4%) and G. lamblia (48.2%). Canine parvovirus type 2 (CPV-2) was specifically associated with diarrheal cases and CPV-2b was the predominant antigenic type. Although canine rotavirus, canine adenovirus, and canine distemper virus were also detected in a small number of diarrheal cases, no evidence for calicivirus infection was obtained.

Animals↗

Three-dimensional transfer functions of coherent anti-Stokes Raman scattering microscopy.

The three-dimensional coherent transfer function of confocal coherent anti-Stokes Raman scattering microscopy was derived theoretically. The three-dimensional optical transfer function was also derived under the weak-contrast assumption. The effect of a pinhole in front of the detector on the optical transfer function was estimated, and it was found that the cutoff frequency of the optical transfer function is independent of the pinhole. Micrometer-order spatial resolution along the optical axis was also experimentally demonstrated.

Microscopy, Confocal↗

Visual demonstration of calcium accumulation in human arteries of upper and lower limbs.

To elucidate the calcium content of the arteries in the upper and lower limbs, the authors determined the calcium content of all the arteries in the upper and lower limbs continuously by microwave-induced plasma-atomic emission spectrometry. The subjects were an 87-yr-old man and a 72-yr-old woman. The calcium content was determined both in the arteries of the upper limbs continuously, such as the subclavian arteries and its distal arteries, and in the arteries of the lower limbs, such as the common iliac arteries and its distal arteries. The common finding that the higher accumulation of calcium occurred in the arteries of the lower limbs in comparison to the arteries of the upper limbs and extremely high accumulation of calcium occurred in the common, external, and internal iliac arteries was obtained in the two subjects. The calcium content of the arteries in the upper and lower limbs was visually demonstrated.

Aged↗

Congestive heart failure caused by aortocaval fistula after nephrectomy.

We treated a 66-year-old man and a 69-year-old woman with high output cardiac failure due to aortocaval fistula. They underwent nephrectomy 40 and 36 years ago, respectively. They suffered from heart failure for a very long time. However, the etiology was not elucidated until recently. The aortogram revealed massive shunt from the aorta to the inferior vena cava via the right renal artery. Three-dimensional computerized tomography clearly delineated the aortocaval fistula. Surgical closure of the fistula promptly improved heart failure. We stress the importance of history taking concerning nephrectomy and the importance of abdominal auscultation in high output cardiac failure.

Aged↗

Churg-Strauss syndrome after reduction of inhaled corticosteroid in a patient treated with pranlukast for asthma.

Recently, various forms of Churg-Strauss syndrome (CSS) have been reported in association with the use of leukotriene receptor antagonists. A 53-year-old woman with a 5-year history of asthma associated with chronic sinusitis presented mononeuropathy, hypereosinophilia, and positive P-ANCA in October 1999. She had been treated with pranlukast (450 mg/day) and beclomethasone dipropionate (BDP) at a dose of 1,200 microg/day which had gradually been tapered to 800 microg/day over the previous 17 months. She was found to have CSS, and 60 mg/day of prednisolone was administered instead of pranlukast, resulting in an improvement of her symptoms and eosinophilia. Later, we confirmed that serum P-ANCA had been positive before the pranlukast treatment, but CSS vasculitis had not appeared at that time. We speculated that an underlying incomplete form of CSS was being masked in this case and that the reduction of inhaled corticosteroid might have been responsible for the unmasking of CSS.

Administration, Inhalation↗

Anticipatory fall in core temperature in rats acclimated to heat given for various hours at a fixed daily time.

Rats were subjected to daily heat exposure limited to a fixed time for 10 consecutive days. An ambient temperature (T(a)) inside an animal room initially set at 24.0 degrees C was raised to 32.0 degrees C, starting at the middle of the dark phase. The high T(a) was maintained for a subsequent 1.5, 3, or 5 h and was then returned to 24.0 degrees C. After the heat exposure schedule, their core temperature significantly fell for about 30 min before and during the period when they had previously been exposed to heat without thermal stimuli. In rats, a time memory for heat exposure could be formed even when the duration of daily heat exposure was short.

Acclimatization↗

Evidence of primary beta-cell destruction by T-cells and beta-cell differentiation from pancreatic ductal cells in diabetes associated with active autoimmune chronic pancreatitis.

OBJECTIVE: Diabetes associated with autoimmune chronic pancreatitis (ACP) is a subtype of diabetes that is responsive to corticosteroid treatment of progressive endocrine and exocrine dysfunction. However, little is known about pathological changes of islet and exocrine pancreas in ACP. RESEARCH DESIGN AND METHODS: We examined pancreatic specimens obtained on biopsy from four diabetic men with ACP (mean [range]: age 62 years [48-78], duration of ACP 3 months [1-5], duration of diabetes 1 month [0-3]) morphologically, immunohistochemically, and morphometrically. RESULTS: The pancreatic specimens in all cases exhibited inflammatory cell infiltration surrounding ductal cells and extensive fibrosis. Some islets were infiltrated with mononuclear cells with disrupted beta-cells. The subsets of T-cells infiltrated to the islets were mainly CD8(+). Islet beta-cell volume was decreased; the mean percentage area of beta-cells in the islets in four cases with ACP were 16% (range 13-20) (P = 0.0015 vs. type 2 diabetic patients, 48% [27-73], n = 8; P = 0.0002 vs. nondiabetic control subjects, 58% [39-77], n = 7). Preserved ductal cells were surrounded predominantly by CD8(+) or CD4(+) T-cells. Some cytokeratin 19-positive ductal cells contained insulin and glucagon, representing upregulated differentiation of islet cells from ductal cells. Insulin promoter factor-1 (IPF-1) was hyperexpressed in insulin-containing ductal cells. CONCLUSIONS: Diabetes associated with ACP is caused by T-cell-mediated mechanisms primarily involving islet beta-cells as well as pancreatic ductal cells. In ACP, ductal islet precursor cells were associated with IPF-1 hyperexpression, suggesting a critical role of IPF-1 on islet cell differentiation and eventual beta-cell restoration.

Acute Disease↗

Spectral analysis of circadian rhythms in heart rate variability of dogs.

OBJECTIVE: To determine characteristics of power spectral analysis of heart rate variability (HRV) during a 24-hour period in dogs and to evaluate the effects of vagal and sympathetic tone on HRV ANIMALS: 16 healthy adult Beagles. PROCEDURE: Power spectral analysis of HRV was conducted, using 24-hour ambulatory ECG recordings. Circadian rhythms were evaluated in terms of absolute units of low-frequency (LF) and high-frequency (HF) powers, their ratio (LF:HF), and their adjusted (normalized) units (LF[norm] and HF[norm]). Three or 4 dogs were used for simultaneous measurement of heart rate and respiratory waveform as well as to evaluate treatment (propranolol, atropine, or both) administered to cause blockade of the autonomic nervous system. RESULTS: Values for LF and HF powers, LF:HF, LF(norm), and HF(norm) had obvious rhythmicity in clinically normal dogs. The HF power of HRV in dogs was extremely high, compared with that of other species, and HF peaks corresponded to peaks obtained from respiratory waveforms. Blockade of the autonomic nervous system documented that HRV in dogs was mostly attributable to vagal activity. CONCLUSION AND CLINICAL RELEVANCE: We determined characteristics of power spectral analysis of HRV in dogs, including circadian rhythm of the autonomic nervous system. Power spectral analysis of HRV may provide a useful noninvasive technique for assessing the effect of drugs on activity of the autonomic nervous system in dogs.

Animals↗

A case of ileus caused by implantation of cancer after surgical treatment of bile duct carcinoma.

We encountered a patient with an ileus caused by implantation of cancer cells after surgical treatment of bile duct carcinoma. The patient was a 55-year-old male diagnosed as having cancer in the lower bile duct who underwent pancreatoduodenectomy in March 1996. The comprehensive curability was B. The patient experienced nausea and vomiting and was diagnosed as having ileus in October 1998. The symptoms were alleviated by medical treatment. Because ileus symptoms recurred in December 1998 but were not alleviated by medical treatment, the patient was hospitalized in Kurume University Hospital for surgery. A mirror reflection was observed by plain radiography of the abdomen. Ultrasonography (US) revealed dilation of the intestinal duct and hypertrophy of the intestinal wall. An ileus tube was inserted but the symptoms did not improve, and therefore, the patient underwent surgery in February 1999. Upon laparotomy, a node of milk white color about 2 cm in size was found in the region coinciding with the enhancement on CT images, and part of the intestinal duct was found to be folded and adhered to the lower surface of the liver. No recurrence was observed in the liver, peritoneum, and lymph nodes. The tumor was excised together with part of the intestinal duct and liver to remove the ileus. At present, the patient is alive without recurrence. Because recurrence of cancer by implantation of cancer cells is often localized in a limited region, early diagnosis and excision are important.

Bile Duct Neoplasms↗

Evaluation of simultaneous excision of pancreatic cancer and the surrounding blood vessels.

Of the 139 patients who underwent excision for invasive cancer in the pancreatic duct at Kurume University Hospital between January 1965 and December 1998, the subjects were 38 patients in whom blood vessels around the cancer were simultaneously excised. The surgical methods were pancreatoduodenectomy (PD) in 31 patients, distal pancreatectomy (DP) in 5, and total pancreatectomy (TP) in 2. The excised blood vessels were the portal vein alone in 32 patients, the artery alone in 1, and both portal vein and artery in 5. Excision of the portal vein was performed by circumcision in 25 patients and by segmentectomy in 12. The range of circumcision was 1.0-7.0 cm (mean, 3.5 +/- 1.4 cm), and the blocking time of the portal vein was 8-36 min (mean, 19.5 +/- 8.8 min). Of the 25 patients who underwent circumcision, reconstruction was performed by end-to-end anastomosis in 23 and by transplantation of the autologous vein between the ends in 2. Of the 12 patients who underwent segmentectomy, direct suture was performed in 10, and transplantation of an autologous vein patch was performed in 2. Postoperative complications occurred in 14 of the 32 patients. In 5 of the 6 patients who underwent excision of the artery, reconstruction was performed by end-to-end anastomosis in 3 and by transplantation of the autologous vein between the ends in 2. Postoperative complications did not occur in the patient who had undergone excision of the artery alone, but 4 of the 5 patients who had undergone simultaneous excision of the portal vein and artery had postoperative complications, of whom 2 died during the period of hospitalization. Three patients with pv0, pv1 or pv2 survived for more than 3 years. Because some of the patients who had undergone excision of the portal vein alone survived for a long time and this method is relatively safe, this surgery can be generally applied, but simultaneous excision of the portal vein and artery should be carefully applied because the incidences of postoperative complications and death during the period of hospitalization are high. With the development of surgical techniques and postoperative control, simultaneous excision of pancreatic cancer and the surrounding blood vessels has become safe, but this method should only be applied to patients who have the potential to recover completely.

Hepatic Artery↗

A case of hepatocellular carcinoma rupturing after angiography.

We report a case of primary hepatocellular carcinoma (referred to as hepatocellular carcinoma below) apparently rupturing after angiography. The patient was a 62-year-old male who was admitted for the treatment of hepatocellular carcinoma. Ultrasonography (US) and computed tomography (CT) on admission showed a tumor occupying the entire left lobe of the liver and partly protruding outside the liver and a tumor embolus in the portal vein. We performed preoperative angiography, after which fever and abdominal discomfort appeared. Two days after the angiography, abdominal pain and a rapid increase in the size of the abdominal tumor were noted. US also revealed an unquestionable increase in the size of the tumor, leading to a diagnosis of intratumoral hemorrhage due to the rupture of hepatocellular carcinoma. Since child classification A, clinical stage I and ICG 11.7% indicated an adequate functional reserve of the liver, we performed an emergency operation. Laparotomy revealed that the tumor occupied almost the entire left lobe of the liver, partly protruded outside it, and was bleeding from part of its anterior surface. The volume of intra-abdominal hemorrhage was about 100 ml. A portal tumor embolus was present in the portal vein from the horizontal part to the trunk. We performed resection of the left and caudate lobes of the liver with removal of the portal tumor embolus. The resected specimens showed a hemorrhage in and around the tumor. We speculated that in a hepatocellular carcinoma that involves the surface of the liver and is complicated by tumor embolism of the portal vein, angiography could trigger the rupture of the carcinoma.

Angiography↗

Clinicopathological evaluation of surgical treatment for early gallbladder cancer.

We evaluated the therapeutic principles for early gallbladder cancer based on clinicopathological characteristics and outcomes in 27 patients encountered at the Kurume University Hospital between January, 1975 and December, 1999. Concerning the depth of wall penetration, 15 patients had mucosal cancers (m-cancers), and 12 patients muscularis propria cancers(mp-cancers). The gross patterns were lp (pedunculated) in 16 patients, ls (sessile) in 3 patients, IIa (flat elevated) in 4 patients, and IIb (flat) in 4 patients. The operative procedure used was cholecystectomy (C) in 12 patients, 4 of whom underwent lymph node dissection. Full-thickness cholecystectomy (FTC) was carried out in 3 patients, one of whom had lymph node dissection. Combination of C and gallbladder bed resection (GbBR) was performed in 7 patients, 6 of whom had lymph node dissection. Combination of C and bile duct resection (BDR), and lymph node dissection was performed in 1 patient. Combination of C and GbBR and BDR, and lymph node dissection was performed in 6 patients. All the patients who underwent lymph node dissection were negative for metastasis. Of the 27 patients, 2 underwent laparoscopic operation: one with m-cancer was 79 years old, and the other with mp-cancer 86 years old. In the m-cancers, no lymphatic, venous or perineural infiltration was observed. In contrast, in the mp-cancers, lymphatic and venous infiltration each were observed in 4 patients (33.3%), although no perineural infiltration was observed. A diagnosis of gallbladder cancer was made postoperatively in 6 patients, of whom 4 had the IIb pattern and all were complicated by gallstone, indicating the difficulty of diagnosing the IIb pattern. The 5-year survival rates for the m- and mp-cancers were as high as 90.9% and 80.8%, respectively. As a curative surgical technique for m- and mp-cancers, lymph node dissection should be performed in addition to FTC, GbBR, and BDR, in combination. When a postoperative histopathologic diagnosis of gallbladder cancer has been made, no second-look operation should be performed for m-cancers, but lymph node dissection of up to the second group should be performed for mp-cancers in a second-look operation.

Aged↗

FR901469, a novel antifungal antibiotic from an unidentified fungus No. 11243. III. Structure determination.

A novel antifungal antibiotic, FR901469, was isolated from an unidentified fungus No. 11243. It is a water-soluble 40-membered macrocyclic lipopeptidolactone, consisting of D-Ala, L-Tyr, L-Val, trans-4OH-L-Pro, trans-3OH-L-Pro, threo-3OH-L-Gln, Gly, L-Orn, L-Thr, three residues of D-alloThr and a (3R)-hydroxypalmitic acid. Its structure, including absolute configurations, was unequivocally determined as 1 based on chemical and spectroscopic evidence.

Antifungal Agents↗

[Persistent primitive hypoglossal artery aneurysm--case report].

The aneurysm arising from a persistent primitive hypoglossal artery (PHA) is rare, and only 13 such cases have been reported in literature. We present a 62-year-old woman with an aneurysm of PHA at its junction with the basilar artery. The patient consulted our hospital for a transient loss of consciousness and headaches. No neurological deficit was found, but MRI and MRA showed an aneurysm of the vertebrobasilar junction. Cerebral angiogram after admission showed the aneurysm of PHA at its junction with the basilar artery. Perspective 3D-CTA and 3D-T2 weighted MR images were composed to simulate the condition and aneurysmal surgery via the transcondylar approach was carried out. The aneurysm was successfully clipped and the patient was discharged with no neurological deficits. Perspective 3 D-CTA and MRI simulation were very useful for this operation.

Cerebral Arteries↗