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S Yoshinaga

Publications and source records attributed to S Yoshinaga.

At least 19 recordsLinked to original sources
PubMed2006

An increase in the serum amylase level in patients after peroral double-balloon enteroscopy: an association with the development of pancreatitis.

BACKGROUND AND STUDY AIMS: Double-balloon enteroscopy (DBE) is a novel technique that allows the enteroscope to be inserted deep into the small intestine. The procedure has been thought to be safe, but cases of acute pancreatitis after peroral DBE have recently been observed. The aim of this study was to confirm the occurrence of hyperamylasemia after peroral DBE. PATIENTS AND METHODS: Peroral DBE was carried out in 13 patients from July 2005 to February 2006. Blood samples were taken before and 3 h after the procedure, and serum pancreatic amylase levels were measured. The patients were also evaluated for pancreatic-type abdominal pain after the procedure. Hyperamylasemia after peroral DBE was defined as an elevation of the serum pancreatic amylase level to more than the upper normal limit and twice the level before the procedure. Pancreatitis was diagnosed on the basis of both pancreatic-type abdominal pain and hyperamylasemia. RESULTS: Hyperamylasemia after peroral DBE occurred in six patients (46.2 %). One of the six patients with hyperamylasemia had pancreatic-type abdominal pain after the procedure and developed acute pancreatitis. The average procedure time was 105 min (range 65 - 155 min) in the patients with hyperamylasemia, and did not significantly differ from that in the group without hyperamylasemia (99 min). CONCLUSIONS: Hyperamylasemia after peroral DBE occurs frequently and may be associated with development of pancreatitis.

Adolescent↗
PubMed2003

Genetic susceptibility to thymic lymphomas and K-ras gene mutation in mice after exposure to X-rays and N-ethyl-N-nitrosourea.

PURPOSE: Ras activation is one of the major mechanisms for the development of murine thymic lymphomas by radiation and chemical carcinogens. To gain insight into the relationship between genetic susceptibility and ras gene mutation, the frequency and spectrum of ras gene mutation was examined in thymic lymphomas from susceptible and resistant mice. MATERIALS AND METHODS: K- and N-ras mutations in thymic lymphomas that arose in X-ray-irradiated and N-ethyl-N-nitrosourea (ENU)-treated mice of susceptible C57BL/6, rather resistant C3H and their hybrid B6C3F1 were analysed by polymerase chain reaction-single-strand conformation polymorphism and subsequent DNA sequencing. RESULTS: C57BL/6 exhibited a higher incidence of thymic lymphomas after exposure to X-rays and ENU than C3H, with B6C3F1 being intermediate. K-ras gene mutations occurred frequently in the pathogenesis of ENU-induced thymic lymphomas in susceptible C57BL/6 as opposed to resistant C3H. The ras mutations were more frequent in ENU-induced thymic lymphomas than X-ray-induced thymic lymphomas, and with the latter, there was no clear evidence for strain differences, suggesting that the genetic susceptibility to X-rays was independent of ras activation. The mutations of K-ras in thymic lymphomas from C57BL/6 were predominantly GGT to GAT in codon 12, whereas this mutation type was never found in those from C3H. No strain difference was observed in the nucleotide sequence or expression levels of O(6)-alkylguanine alkyltransferase, indicating that this enzyme did not account for the genetic susceptibility to ras activation. CONCLUSIONS: The results indicate that there is a clear strain and carcinogen dependency of K-ras mutation and that the frequency of ras mutation might determine the genetic susceptibility to ENU-induced lymphomagenesis, whereas pathways independent of ras activation might determine the susceptibility to X-ray-induced lymphomagenesis.

Alkylating Agents↗
PubMed2001

Transit endoscopic ultrasound of colorectal cancer using a 12 MHz catheter probe.

The objective of this study was to examine the accuracy of a 12 MHz ultrasound catheter probe in the pre-operative staging of colorectal cancer by assessing the depth of tumour infiltration and involvement of pericolonic lymph nodes. 159 patients with colorectal cancer who underwent ultrasound examination with a 12 MHz catheter probe were studied prospectively. The results of this imaging procedure were compared with the histological findings of the resected specimens. The accuracy of the 12 MHz ultrasound catheter probe for depth of invasion (T category) was 85% (131/154) for all tumours, 87% (46/53) for pT1 tumours, 60% (9/15) for pT2 tumours, 89% (74/83) for pT3 tumours and 67% (2/3) for pT4 tumours. The accuracy for tumours of the rectum and colon was 81% and 89%, respectively. The accuracy of the probe for nodal staging (N category) was 67% (76/114) overall. The sensitivity was 70% (33/47), the specificity 64% (43/67), the positive predictive value 58% (33/57) and the negative predictive value 75% (43/57). Endoscopic ultrasound using a 12 MHz catheter probe accurately assessed tumour stage, although nodal staging remained suboptimal. This method may aid in the selection of treatment for patients with colorectal cancer.

Adult↗
PubMed2000

Scalp cavernous angioma presenting as sinus pericranii: diagnostic value of cerebral angiography and magnetic resonance imaging.

OBJECTS: Sinus pericranii is only a symptom complex, and it can have a variety of etiologies. Therefore, it is important to differentiate these etiologies preoperatively by means of radiological examinations. A 5-year-old boy was admitted with a soft and fluctuant tumor in the right parietal region near the midline. The tumor appeared when the child was in a recumbent position, distending noticeably with the Valsalva maneuver and disappearing completely when the patient was in the sitting position. METHODS: Magnetic resonance imaging showed the lesion with honeycomb-like heterogeneous iso- and low-intensity signals on the T1-weighted image and with heterogeneous high- and isointensity signal on the T2-weighted image. Dynamic study with an injection of gadolinium diethylene-triaminopentaacetic acid demonstrated and nodular peripheral enhancement at early phase and subsequent progressive enhancement towards the center of tumor. The internal carotid angiogram was normal. The external carotid angiogram, however, showed a tumor stain fed by the superficial temporal arteries. The stain was retained until the late phase and drained into the scalp veins and into the superior sagittal sinus. Following direct injection of contrast medium into the tumor there was prolonged retention of the medium in the tumor and leakage into scalp veins and the superior sagittal sinus. The mass under the periosteum was totally removed and proved to be a cavernous angioma. CONCLUSIONS: Scalp cavernous angioma is one of the etiologies of sinus pericranii and may be diagnosed preoperatively by cerebral angiography or magnetic resonance imaging. Serial dynamic magnetic resonance imaging will be particularly helpful for this diagnosis.

Cerebral Angiography↗
PubMed1999

Hyponatremia-induced metabolic encephalopathy caused by Rathke's cleft cyst: a case report.

Rathke's cleft cysts are sometimes associated with aseptic meningitis or metabolic encephalopathy due to hyponatremia. We treated such a case manifest by lethargy, fever and electroencephalographic abnormalities. A 68-year-old man was admitted to our ward after experiencing general malaise, nausea and vomiting and then high fever and lethargy. On admission, he was drowsy and had nuchal rigidity and Kernig's sign. Physically, he was pale with dry, thickened skin. He had lost 5.0 kg of body weight in the last month. His serum sodium was 115 mEq/l. He had a low serum osmotic pressure (235 mOsmol/l) and a high urine osmotic pressure (520 mOsmol/l). His urine volume was 1200-1900 ml/24 h with a specific gravity of 1008-1015. The urine sodium was 210 mEq/l. He did not have an elevated level of antidiuretic hormone. Electroencephalograms showed periodic delta waves over a background of theta waves. With sodium replacement, the patient become alert and symptom free, and his electroencephalographic findings normalized. However, the serum sodium level did not stabilize, sometimes falling with a recurrence of symptoms. Magnetic resonance imaging clearly delineated a dumbbell-shaped intrasellar and suprasellar cyst. The suprasellar component subsequently shrunk spontaneously and finally disappeared. An endocrinologic evaluation showed panhypopituitarism. The patient was given glucocorticoid and thyroxine replacement therapy, which stabilized his serum sodium level and permanently relieved his symptoms. A transsphenoidal approach was performed. A greenish cyst was punctured, and a yellow fluid was aspirated. The cyst proved to be simple or cubic stratified epithelium, and a diagnosis of Rathke's cleft cyst was made. The patient was discharged in good condition with a continuation of hormonal therapy. Rathke's cleft cyst can cause aseptic meningitis if the cyst ruptures and its contents spill into the subarachnoid space. Metabolic encephalopathy induced by hyponatremia due to salt wasting also can occur if the lesion injures the hypothalamus and pituitary gland.

Aged↗
PubMed1999

Effect of biochemical components on rheologic properties of nasal mucus in chronic sinusitis.

The effect of biochemical components on the viscoelasticity of nasal mucus from 24 patients with chronic sinusitis (CS) was investigated by multiple stepwise regression analysis. The dynamic viscosity (eta') and the elastic modulus (G') of nasal mucus were determined with an oscillating sphere magnetic rheometer at oscillatory frequencies of 1 and 10 Hz. The eta' and G' values of mucus determined at 1 Hz were 1.6 +/- 1.5 Pa/s and 31.8 +/- 31.0 Pa, respectively, and these values were much higher than optimal viscoelasticity for mucociliary transport. The concentrations of fucose, N-acetyl neuraminic acid, albumin, IgG, secretory-IgA, and lysozyme were measured in the same mucus samples. The multiple regression analysis showed that the concentration of fucose, a marker of mucous glycoproteins, was the most important determinant of eta' and G'. The analysis also revealed that the level of IgG was the next important determinant. The coefficients of multiple determination for fucose and IgG were 0.732 and 0.733 when the response variables were eta' and G', respectively. The results indicate that locally produced mucous glycoproteins may largely contribute to the high viscoelasticity of nasal mucus in CS.

Adolescent↗
PubMed1999

Spontaneous cerebrospinal fluid leakage detected by magnetic resonance cisternography--case report.

A 49-year-old male with no history of head trauma suffered cerebrospinal fluid (CSF) discharge from the left nostril for one month. Coronal computed tomography (CT) showed lateral extension of the sphenoid sinus on both sides and CSF collection on the left side. CT cisternography could not identify the site of CSF leakage. Heavily T2-weighted magnetic resonance (MR) imaging (MR cisternography) in the coronal plane clearly delineated a fistulous tract through the sphenoid bone into the sphenoid sinus. Patch graft with muscle fragment completely relieved the CSF rhinorrhea. Postoperative three-dimensional CT showed the two bone defects identified during surgery. Small bony dehiscences in the sphenoid bone and lateral extension of the sphenoid sinus predisposed the present patient to CSF fistula formation. MR cisternography in the coronal and sagittal planes is superior to CT scanning or CT cisternography for detection of the site of active CSF leakage.

Cerebrospinal Fluid Rhinorrhea↗
PubMed1999

Cancer mortality among radiological technologists in Japan: updated analysis of follow-up data from 1969 to 1993.

A retrospective cohort study was conducted for 12,195 male radiological technologists who received the occupational exposure to low dose radiation over a long term. A total of 1,097 deaths including 435 from cancer were ascertained by Koseki and death certificates from 1969 to 1993. Cancer mortality among the study population was basically compared with that of whole Japanese men. The significant low SMRs were obtained for all cancers, stomach and lung cancer partly due to Healthy Worker Effect, unlike the results of the early reports with some inappropriateness in the methods. Apparent high risks of lymphatic and hematopoietic cancers were observed, although none of site-specific cancers revealed the statistically significant increase. For these cancers, the SMRs among old sub-cohort were somewhat higher than those of young sub-cohort, whereas similar SMRs for solid cancer were obtained between the two sub-cohorts. The SMR for leukemia reached statistically significant level of 1.75 (95% CI: 1.07-2.71) when using whole professional and technical workers as a standard population. The study results might suggest that the chronic exposure to low-dose radiation enhanced the risk of lymphatic and hematopoietic cancers.

Adult↗
PubMed1999

Relationships between activity of daily living, and oral cavity care and the number of oral cavity microorganisms in patients with cerebrovascular diseases.

We examined the relationships among the activity of daily living (ADL), oral cavity care, and the number of oral cavity microorganisms in 40 patients with cerebrovascular diseases (CVD). The CVD patients were classified into 4 groups, I, II, III and IV based on their ADL and the method used for oral cavity care. The ADL was highest in group I and lowest in group III. Only the patients of only group III could not eat by themselves and were receiving naso-esophageal feeding. Oral cavity care was performed by the patients themselves in groups I and IV, but was performed by caregivers in groups II and III. The group IV patients had no teeth, but could eat by themselves using full dentures. The numbers of microorganisms in the pharyngeal swabs from the 4 groups were measured and expressed as colony-forming units (cfu). The numbers of both Staphylococci spp. and Candida spp. were significantly higher in group III than in the other groups. Moreover, Pseudomonas aeruginosa was isolated only from patients of group III (in about 66%). The oral cavity care by caregivers was almost the same in groups II and III, but the numbers of oral cavity microorganisms were significantly higher in group III than in group II. These results indicated that microorganisms grow more easily in the oral cavities of CVD patients with low ADL compared with CVD patients with higher ADL, and that eating is thought to be important for the prevention of an increase of microorganisms in the oral cavity.

Activities of Daily Living↗
PubMed1998

Postoperative subarachnoid clots and the pattern of cerebral ischemia associated with symptomatic vasospasm.

OBJECTIVE: We retrospectively evaluated the presence of subarachnoid clots and the development of symptomatic vasospasm in 125 patients who had early surgical treatment of a ruptured cerebral aneurysm. SUBJECTS AND METHODS: We studied 16 patients (aged 35-86 years; mean, 58.7 years) who underwent surgery 0 to 6 days (mean, 2.1 days) and then manifested symptomatic vasospasm on day 5-12 (mean, day 7.4), and 57 patients (aged 13-79 years; mean, 52.0 years) who underwent surgery 0-8 (mean, day 2.9) and did not manifest symptomatic vasospasm. The volume and location of subarachnoid clots were evaluated with computed tomographic (CT) scanning. Cerebral ischemia was evaluated clinically and also in eight patients, by measurement of cerebral blood flow (CBF) using xenon-enhanced CT. Angiographic evaluation was performed only on one patient. RESULTS: Of the 16 patients with symptomatic vasospasm, the subarachnoid clots were localized, distributed thickly, or associated with intracerebral hematomas in 15 and thin in 1 at the time of admission. Fifteen patients had CT evidence of a subarachnoid clot during vasospasm. Most of the clots were near the ruptured aneurysms, but in three cases, clots were located in the remote cisterns, which were not accessible operatively. The clinical manifestations of vasospasm in these three patients correlated with the site of the clot. CBF was reduced in the territory of the involved artery in all eight patients in whom it was measured. In two of the eight cases, the reduction occurred in the territory of a contralateral artery. In contrast, in the 57 patients without symptomatic vasospasm, the subarachnoid clots were already gone or disappeared soon after surgery in most patients. CONCLUSIONS: The continued presence of subarachnoid clots is an important risk factor for symptomatic vasospasm after the rupture of a cerebral aneurysm. The clot is not always located near the ruptured aneurysm, and the clinical course may be unpredictable.

Adult↗
PubMed1998

Quantitative electroencephalographic correlates of cerebral blood flow in patients with chronic subdural hematomas.

BACKGROUND: We have observed that the reduction in cerebral blood flow (CBF) of patients with chronic subdural hematomas is always most pronounced in the thalamus and has a linear correlation with the degree of brain deformity caused by the compression from the hematoma. When the brain is markedly displaced by a hematoma, electroencephalography (EEG) shows delta waves in the frontal region. We theorized that the flow reduction begins in the thalamus, spreading throughout the hemisphere as displacement progresses. METHODS: We measured CBF using the xenon/computed tomography (CT) method in 10 patients with chronic subdural hematomas who had hemiparesis and/or a mental disturbance and radiographic evidence of a midline shift or herniation. We correlated their flow reductions with topographic encephalograms. RESULTS: Flow reductions were more pronounced in the thalamus than in the hemisphere and cortex. Slow waves dominated over fast waves, especially in the frontopolar and frontal regions bilaterally. Flow values correlated negatively with the presence of delta and theta waves and positively with that of alpha and beta waves. On the side of the hematoma, the brain wave activity correlated significantly with thalamic flow, and the correlation was greater than with the hemispheric or cortical flow. Thalamic flow correlated more consistently with delta and alpha waves in the central, temporal, and occipital regions, and with beta waves in the frontopolar, frontal, and central regions. On the nonhematoma side, the correlation between brain wave activity and hemispheric flow was significant and greater than with cortical or thalamic flow. CONCLUSIONS: The correlation of EEGs with thalamic flow, which was maximally reduced, seems to substantiate the concept that the thalamus is primarily injured by brain distortion due to the compression from hematoma and that the remote areas are secondarily deactivated by a transneural depression ("diaschisis") originating from the dysfunctioning thalamus. Thalamic involvement seems to be the cause of the neurologic dysfunction and the abnormal EEG activity in chronic subdural hematomas.

Aged↗
PubMed1998

Extensive edema in the thalamus caused by thrombosed basilar artery aneurysm.

A 69-year-old female presented with sudden onset of truncal ataxia, urinary incontinence, mental confusion, and Parinaud's sign. With conservative treatment, her ataxia and urinary incontinence resolved. Magnetic resonance (MR) imaging disclosed a round mass with laminated intramural hemorrhage in the third ventricle. Right vertebral angiography demonstrated a giant aneurysm in the distal basilar artery. Xenon-enhanced computed tomography showed that cerebral blood flow (CBF) was reduced in the thalamus bilaterally and was paradoxically decreased by acetazolamide. Two months later, MR imaging showed that the intramural hemorrhage had shrunk, and the edema in the thalamus was resolving. The CBF reduction and vascular response to acetazolamide had reversed to some extent. A partially thrombosed giant aneurysm can grow acutely as the result of fresh intramural hemorrhage. The edema is secondary to ischemia and loss of vasoresponsivity.

Aged↗