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K Minowa

Publications and source records attributed to K Minowa.

At least 19 recordsLinked to original sources
PubMed2006

Static bone cavity of the mandible: Computed tomography findings with histopathologic correlation.

PURPOSE: To review computed tomography (CT) findings of histopathologically examined static bone cavities in order to determine whether an additional pathogenesis may play a role in this disease. MATERIAL AND METHODS: Four patients with histopathologically examined static bone cavities were included in this retrospective study. Location, appearance of bone remodeling, tissue characteristics, and contrast enhancement of the cavity were assessed on CT images. CT findings were then compared with the histopathological findings. RESULTS: Static bone cavity was found in the lingual molar region in three patients and in the lingual cuspid region of the mandible in one patient. Both fatty and soft tissues were present in the cavities of all four patients. Attenuation of the soft tissue in the cavities was found to be different from that of the submandibular gland. The soft tissue showed enhancement with contrast-enhanced CT in three patients. For all patients, the histopathologic content of the static bone cavity included fat, soft tissue, and abnormal vasculature. The thickened vein wall in the abnormal vasculature was observed. Aberrant tissue of the submandibular gland was not found in any of the static bone cavities. CONCLUSION: Contrast enhancement of the soft tissue on the contrast-enhanced CT images suggests the presence of vasculature in the cavities. Histopathological examination confirmed the presence of fatty tissue and dilated abnormal vessels, and the absence of salivary gland tissue in the cavities. These findings show that vascular structures are prominent in tissues found in static bone cavities.

Adult↗
PubMed2005

The influence of hot pack therapy on the blood flow in masseter muscles.

The purpose of this study was to clarify whether hot pack therapy can change the blood flow of human masseter muscles. Thirty-two healthy subjects with no history of muscle pain in the masticatory system participated and were divided into two groups. One group underwent proper hot pack therapy (hot pack group) and the other underwent sham hot pack therapy (control group). Continuous and non-invasive measurements of haemoglobin volumes and oxygen saturation levels (StO2) were determined with a near-infrared spectroscope. The blood flow parameters were total haemoglobin volume (THb), oxygenated haemoglobin volume (OXHb), deoxygenated haemoglobin volume (deOXHb) and oxygen saturation level (StO2). In hot pack group, results showed that the THb, OXHb and StO2 after the hot pack application were significantly larger than those before the hot pack. In control group, the THb, OXHb, deOXHb, StO2 and heart rates showed no significant differences between the values before and after the sham hot pack application. The THb, OXHb and StO2 after the hot pack application in hot pack group were significantly larger than those in control group, while the deOXHb after the hot pack was significantly smaller than that in control group. The heart rates showed no significant differences between the groups. The results suggest that hot pack therapy can increase regional blood flow of human masseter muscles and creates an advantageous condition for aerobic energy metabolism in the muscles.

Adult↗
PubMed2003

Evaluation of static bone cavities with CT and MRI.

OBJECTIVES: To determine by CT and MRI the contents of static bone cavities (SBCs), which are thought to be formed by aberration of the submandibular gland. METHODS: Non-contrast-enhanced and contrast-enhanced CT was performed on 12 subjects (10 male and 2 female; age 18-64 years; mean age 57 years) in whom SBCs had been discovered incidentally on panoramic radiographs during routine dental treatment. MRI was also performed on 3 of the 12 subjects. RESULTS: No submandibular gland tissue was seen in the SBCs in any of the cases. However, fatty tissue of low attenuation was found in the SBCs in all cases on CT images. Blood vessels were seen in the SBCs in 10 cases, and enhanced soft tissue in contact with the bone cavity wall was seen in the SBCs in 2 cases. Blood vessels in the SBCs were observed on MR images in all three cases. Dilatation of the cavity blood vessels was seen in all 10 cases. Slight tortuosity of the blood vessels was seen in 4 of the 10 cases. CONCLUSIONS: Examination of contrast-enhanced CT images and MR images revealed that the contents of SBCs were not aberrations of the submandibular gland, as has generally been thought, but fatty tissue, blood vessels and soft tissue.

Adipose Tissue↗
PubMed2002

Electromyographic activity of the jaw-closing muscles during jaw opening--comparison of cases of masseter muscle contracture and TMJ closed lock.

Contracture of jaw-closing muscles is one of the causes of limitations of jaw opening. In contracture patients who have no history of trauma or infection, it is not easy to distinguish contracture from temporomandibular joint (TMJ) closed lock (TCL). The purpose of this study was to clarify whether there is any difference between electromyographic (EMG) activities of jaw muscles during jaw opening in patients with TCL and patients with masseter muscle contracture (MMC). The MMC-patient group consisted of one male and 11 females with no history of trauma or infection. The TCL-patient group consisted of one male and 11 females. Ten of the MMC patients showed certain types of EMG activities in masseter muscles (and eight in temporal muscles) during jaw opening. However, particular EMG activities were not observed in most of the TCL patients. The integral values in masseter muscles and in temporal muscles at the maximum opening position were significantly higher in the MMC-patient group than those in the TCL-patient group. These findings demonstrate that the EMG pattern of MMC patients without a history of trauma or infection is different from that of TCL patients. Therefore, EMG analysis of jaw-closing muscles during jaw opening is expected to be useful for differential diagnosis between MMC and TCL.

Adolescent↗
PubMed2001

A study of quality assessment in clinical microbiology performance of independent laboratories in Tokyo: 18-year participation in the Tokyo Metropolitan Government External Quality Assessment Program.

We evaluated the performance of independent microbiology laboratories in Tokyo over an 18-year period of participation in the external quality assessment (EQA) program, and we estimated the impact of the EQA program. The study design was a longitudinal retrospective analysis of performance, including isolation, identification, and antimicrobial susceptibility testing of bacteria from simulated patients' samples, in "open" surveys compared with "blind" surveys. Independent microbiology laboratories, licensed by the Tokyo Metropolitan Government, have been subject to mandatory evaluation by the EQA program since 1982. Survey reports, correspondence, annual guidance meetings, and inspections are used as quality improvement strategies. The performance for identification in "blind" surveys was significantly worse than that in "open" surveys (P < 0.001). Poorly performing laboratories had common features, including inadequate supervision by physicians and lack of familiarity with the impact of variations on the use of the standards. However, there were improvements in the performance of identification of some pathogens. The performance of susceptibility testing has not yet reached the relatively high level seen for identification. Some of the smaller laboratories have been gradually acquired by commercial chains operating outside Tokyo. The EQA program has established a role both in regard to laboratory improvement and as an educational tool. However, the program lags behind these of other developed countries in regard to the practical sciences. The main problems in regard to laboratory improvements are a shortage of human resources in clinical microbiology, lack of standardization of laboratory methods, and the pressures of financial constraints in the Japanese medical insurance system.

Data Collection↗
PubMed2001

Comparison of phosphocreatine concentration in the human masseter and medial pterygoid muscles by 31P-CSI.

The aim of this study is to compare phosphocreatine (PCr) concentrations of human masseter and medial pterygoid muscles by a recently developed localized magnetic resonance spectroscopy (MRS) method, chemical shift imaging (CSI). The characteristic spectra of phosphorous metabolites including PCr and beta-ATP from the superficial part of the masseter (SM) and the deep part of the masseter (DM) and the medial pterygoid muscles (MPt) from 11 volunteers, 20-27-year-old were obtained. The study clearly demonstrated higher PCr/beta-ATP in the SM and MPt than in the DM both in mean values (P < 0.01) and in individual subjects. The results indicate that SM and MPt are power producers. There were no significant differences in the mean values of the PCr/beta-ATP ratios in SM and MPt, however, the PCr/beta-ATP ratios varied individually and the subjects could be divided into three distinct groups: values of MPt higher than SM (group A, 4 subjects); values of MPt almost equal to SM (group B, 3 subjects); and values of MPt lower than SM (group C, 4 subjects). There appears to be a close relationship between the PCr content as determined in the groups here and occlusal guidance.

Adenosine Triphosphate↗
PubMed2001

Analyses of muscular activity, energy metabolism, and muscle fiber type composition in a patient with bilateral masseteric hypertrophy.

Hyperwork of the masseter muscles due to habitual parafunction is thought to induce masseteric hypertrophy (so called work hypertrophy). However, the causes underlying this disease are not yet fully understood. Recently, we had a patient with bilateral masseteric hypertrophy, and we performed a partial excision of the masseter muscles. In this patient's case, we examined muscular activity, energy metabolism, and fiber type composition of the masseter muscles using electromyograms (EMG), 31P-magnetic resonance spectroscopy (MRS), and enzyme-histochemistry. The EMG showed no hyperactivity, and the 31P-MRS showed normal energy spectral patterns and PCr contents of the masseter muscles. The fiber type composition, however, in the muscles in this case was very different from that in muscles with "work hypertrophy" and also that in normal masseter muscles: 1. Loss of type IIB fibers; 2. Increases in type IIA and in type IM & IIC fibers; and 3. Decrease in type I fibers. The findings suggest that this is not a case of work hypertrophy but a case of compensatory hypertrophy possibly due to a lack of high-tetanus-tension type IIB fibers.

Adenosine Triphosphate↗
PubMed2000

Nicotine attenuates stress-induced changes in plasma amino acid concentrations and locomotor activity in rats.

It is known that stressor stimuli (both systemic and processive) and nicotine activate central nervous system. Surprisingly, numerous studies have demonstrated an increase in nicotine self-administration among smokers when exposed to stress in order to reduce the stress-related tension. Therefore, in the present study, we decided to investigate the influence of nicotine on both behavioral (i.e., on locomotor activity) and metabolic (i.e., on the level of amino acids in the plasma) changes following water immersion restraint stress in rats. As expected, the stress produced evident decline in locomotor activity of the rats (p < 0.001) and in the levels of all plasma amino acids studied (p < 0.05). Nicotine alone also significantly reduced locomotor activity (p < 0.05) and the levels of some plasma amino acids. However, when administered to rats subjected to water immersion and restraint, nicotine attenuated both stress-induced decrease in locomotor activity (p < 0.05) and in some plasma amino acids. Thus, this study demonstrated that the mode of action of nicotine is strongly dependent on the level of initial brain activity, which provide new evidence for arousal-modulation model of nicotine action.

Amino Acids↗
PubMed2000

Regional differences of metabolism in human masseter muscle by two-dimensional 31P-chemical shift imaging.

Many reports have demonstrated significant region-dependent differences in the fiber-type composition of the human masseter muscle. Therefore, it is considered that there is intramuscular heterogeneity of metabolic activity in the muscle. The present study was carried out, with two-dimensional Chemical Shift Imaging, to detect differences between the deep and superficial parts of the human masseter muscle at rest. Masseter muscle from 11 volunteers, from 20 to 27 years old, was examined, and characteristic spectra of the inorganic phosphate (Pi), phosphocreatine (PCr), and alpha-, beta-, and gamma-adenosine triphosphate (ATP) from each part of the muscles were obtained. In this study, the deep and superficial parts of the masseter muscle were distinguished by the existence of aponeurosis. The Pi/PCr, PCr/beta-ATP, and Pi/beta-ATP ratios as well as the pH in the deep and superficial parts were calculated from the peak spectra. Compared with the deep part, the Pi/PCr of the superficial part was lower (p < 0.05) and the PCr/beta-ATP was higher (p < 0.01). The Pi/beta-ATP and pH showed no significant differences between the two parts. The results indicate that the superficial part of the masseter muscle contains more PCr than the deep part, and this may be related to functional differences between these two parts. In future examinations of the metabolic activity of the human masseter muscle, the deep and superficial parts must be measured separately.

Adenosine Triphosphate↗
PubMed1999

MRI of the brain in the Kearns-Sayre syndrome: report of four cases and a review.

We report brain MRI findings in four patients with typical Kearns-Sayre syndrome (KSS) and correlate them with clinical manifestations. MRI was interpreted as normal in two patients; cerebral and cerebellar atrophy was seen in the other two. On T2-weighted spin-echo images, two patients had high-signal lesions bilaterally in subcortical white matter, thalamus and brain stem. In one patient, the white matter lesion extended into the deep cerebral white matter and the cerebellum was also affected. The other also had bilateral high-signal lesions in the globus pallidus. There was little correlation between neurological deficits and MRI findings. A review of the literature revealed that 10 of the 13 patients with typical KSS previously studied had bilateral subcortical white-matter lesions on T2-weighted images; at least 7 also had high-signal lesions in the brain stem, globus pallidus, thalamus or cerebellum. Although MRI may be normal or show atrophy, the characteristic finding in KSS is a combination of the high-signal foci in subcortical cerebral white matter and in the brain stem, globus pallidus or thalamus.

Adolescent↗
PubMed1998

Comparison of magnetic resonance imaging and gross findings regarding masseter muscle aponeuroses in cadavers.

OBJECTIVES: The main objective of this study was to compare the actual distribution and thickness of aponeuroses in cadavers with the distribution and thickness as determined by means of magnetic resonance imaging for the sake of evaluating magnetic resonance imaging as a diagnostic modality for assessing masseter muscle aponeuroses. STUDY DESIGN: The aponeuroses of 26 masseter muscles from 13 intact cadavers were examined by magnetic resonance imaging. RESULTS: The ratio of concordance between gross findings and magnetic resonance imaging findings was 99.0%, although depiction of thin parts of the aponeuroses on magnetic resonance imaging was poor. CONCLUSIONS: Magnetic resonance imaging was useful as a diagnostic modality in the assessment of masseter muscle aponeuroses. Aponeuroses were distributed throughout almost the entire masseter muscle, although almost no aponeuroses were seen below the lower half of the anterior margin. This was thought to be a characteristic finding of masseter aponeuroses.

Aged↗
PubMed1996

[A case of ureteral malacoplakia in a hemodialysis patient].

A case of ureteral malacoplakia in a hemodialysis patient is reported. A 64-year-old woman suffering from macrohematuria, was diagnosed as having a right ureteral tumor by means of computerized tomography and antegrade pyelography. Right nephroureterectomy with bladder cuff resection was performed. Pathological examination indicated malacoplakia; multiple Michaelis-Gutmann bodies were found. The patient did well postoperatively and was discharged without further complications. This case appears to be the twenty-first report of ureteral malacoplakia in the world.

Female↗
PubMed1994

Contingent negative variations associated with jaw opening in humans.

We examined the relationship between contingent negative variation (CNV) amplitude and digastric muscle activity in jaw-opening motor task. Subjects were instructed to open their jaws in response to a sound stimulus following a visual warning stimulus. Electroencephalograms were averaged by using the visual stimulus pulse as a trigger. Bilateral CNVs were clearly recorded at several cortical locations, with a tendency for larger amplitudes at temporal placements.

Adult↗
PubMed1994

[Whipple's disease].

Explore the source record for details and available documents.

Diagnosis, Differential↗
PubMed1993

Intrahepatic portosystemic venous shunt: diagnosis by color Doppler imaging.

Intrahepatic portosystemic venous shunt is a rare clinical entity; only 33 such cases have been reported. It may be congenital, or secondary to portal hypertension. Five patients with this disorder are presented, each of whom was diagnosed by color Doppler imaging, including waveform spectral analysis. One patient with clinical evidence of cirrhosis and portal hypertension had episodes of hepatic encephalopathy and elevated blood levels of ammonia. This patient had a large tubular shunt between the posterior branch of the portal vein and the inferior vena cava. Shunts of this type are considered to be collateral pathways which develop in the hepatic parenchyma as a result of portal hypertension. The other four patients had no evidence of liver disease, and all four evidenced an aneurysmal portohepatic venous shunt within the liver parenchyma. Shunts of this type are considered congenital. The diagnosis of intrahepatic portosystemic venous shunts was established by color Doppler imaging, which demonstrated a direct communication of color flow signals between the portal vein and hepatic vein, in addition to the characterization of the Doppler spectrum at each sampling point from a continuous waveform signal (portal vein) to a turbulent signal (aneurysmal cavity), and finally, to a biphasic waveform signal (hepatic vein). As demonstrated by the five patients, color Doppler imaging is useful in the diagnosis of an intrahepatic portosystemic hepatic venous shunt, and the measurement of shunt ratio may be useful in the follow-up and determining the therapeutic option.

Adult↗