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Biomedical subjects

A Nakashima

Publications and source records attributed to A Nakashima.

179 records · Page 10Linked to original sources
PubMedDate not supplied

Thoracic esophageal carcinoma: evaluation in the sagittal section with magnetic resonance imaging.

Among 54 patients with thoracic esophageal carcinoma (53 squamous cell carcinoma, 1 adenosquamous carcinoma), the usefulness of MR sagittal imaging for evaluating local extent (T factor) was examined by measuring the anteroposterior (AP) diameter of the tumor. The MR examination was performed using ECG gated scans with a 3 mm slice at 1.5 Tesla. T1-weighted sagittal images were obtained. In 10 patients the appearance of the esophagus was normal, and in 44 patients a tumor was detected in the sagittal section. Thirty-seven lesions were histologically proved (Tis, 1; T1, 3; T2, 3; T3, 15; T4, 15). Lesions classified as 30 mm were resected. They were located in the lower esophagus. It is concluded that lesions detected in MR sagittal images might be T3 or T4 tumors, and masses of >30 mm might extend to adjacent organs, although two tumors with an AP diameter < 25 mm also invaded the trachea.

Adult↗
PubMedDate not supplied

Clinical utility of three-dimensional time-of-flight magnetic resonance angiography for the evaluation of intracranial aneurysms.

Magnetic resonance (MR) angiographic studies of 14 patients with intracranial aneurysms (AN) were analyzed retrospectively as compared with contrast angiographic studies. Eighteen of 19 (95%) lesions were detected, and the relation between AN and their parent vessels was precisely assessed. The diameter of the smallest aneurysm detected in our case was 3 mm. However, small vessels around AN were not visualized. Therefore, MR angiography (MRA) is definitely not a substitute for preoperative contrast angiography. MRA is a useful screening tool for nonruptured AN, but further refinement is required to evaluate emergency ruptured AN.

Adolescent↗
PubMedDate not supplied

Computed tomography in amyloid goiter.

Two cases of amyloid goiter showed diffuse decreased density of enlarged thyroid on CT. The diffuse decreased density of amyloid goiter on CT is thought to represent large amount of adipose tissue often found in amyloid goiter. When diffuse decreased density of the enlarged thyroid is recognized on CT, amyloid goiter should enter into differential diagnosis.

Adult↗
PubMedDate not supplied

Appendiceal mucocele of mucinous cystadenocarcinoma with a cutaneous fistula.

We report a novel case of cystadenocarcinoma forming an appendiceal mucocele with development of a skin fistula. The patient was a 75-year-old Japanese woman who originally presented with a skin ulcer on the right flank (inferior to the ribs and superior to the iliac bone) with mucus discharge. The serum concentration of carcinoembryonal antigen was elevated (57.4 ng/ml). Ultrasonography and computed tomography demonstrated a cystic mass with septations in the right iliac fossa. Fistulography from the skin ulceration showed a communication via the fistula to the caecum. A right hemicolectomy and enbloc resection of the skin fistula was performed. The histological findings revealed a well-differentiated mucinous cystadenocarcinoma of the appendix. The patient has been alive for 7 years following surgery without any sign of recurrence. This report is of interest as it demonstrates that tumour rupture to the extraperitoneal space could result in a good outcome by preventing the development of pseudomyxoma peritonei.

Aged↗
PubMedDate not supplied

An epidemiologic model for diabetes mellitus: incidence, prevalence, and mortality.

An epidemiologic model is developed to describe the incidence, prevalence, and mortality of diabetes. Available data are reviewed, analyzed, and applied to the model. The model provides a framework for understanding diabetes on a population basis, and is useful in identifying needs and facilitating health care planning.

Adult↗
PubMedDate not supplied

Telomerase activity in gliomas with the use of non-radioisotopic and semi-quantitative procedure for terminal repeat amplification protocol.

To study the role of telomerase in the pathogenesis of different grades and subtype of gliomas, telomerase activity in 31 gliomas was assessed with the use of non-radioisotopic and semi-quantitative procedures for the terminal repeat amplification protocol in this study. Among the samples were 17 glioblastoma multiformes (GBMs); 4 anaplastic astrocytomas (AAs); 5 astrocytomas (ASs); 1 ependymoblastoma (EPB); 2 ependymomas (EPs); 1 oligodendroglioma (OG) and 1 medulloblastoma (MB). Postive telomerase activity was detected in 9 of 17 GBMs (53%), 1 of 4 AAs (25%), 1 of 5 ASs (20%), 1 of 1 EPB (100%), and in positive controls, T 98G and KE-1. Weakly positive activity was detected in 2 of 3 AAs (66%) and 2 of 5 ASs (40%). No telomerase activity was detected in 8 of 17 GBMs (47%), 1 of 4 AAs (25%), 2 of 5 AS (40%), 2 of 2 (100%) EPs, 1 of 1 OG (100%), 1 of 1 MB (100%) and normal brain tissue. We defined telomerase expression as positive and weakly positive cases. The percentage of telomerase activity expression in gliomas tended to correlate with tumour grade in spite of histopathology of tumours. These results indicated that the telomerase activity of gliomas may be used as a tumour marker and that the activation of telomerase should correlate with initiation and malignant progression of gliomas. In addition, non-radioisotopic and semi-quantitative procedure for the terminal repeat amplification protocol appears to be the most suitable to detect telomerase activity expression in small neurosurgical specimens.

Adult↗
PubMedDate not supplied

A case of Japanese encephalitis: CT and MRI findings in acute and convalescent stages.

We studied the CT and MR images of a patient with Japanese encephalitis. The first symptom was general malaise with high fever. The diagnosis of meningoencephalitis was made by spinal tap and clinical presentation. CT on the third day of illness showed no significant findings. MRI on the fifth day of illness demonstrated that the left thalamus and bilateral putamen were hyperintense on T2-weighted images. On CT one month later, the density in the thalamus and bilateral putamen was normal. MRI two month later showed high signal intensity only in the left thalamus. The patient recovered, but was judged to have dementia according to the simple dementia scale of Hasegawa. Flaccid paralysis was observed during the acute period.

Acute Disease↗
PubMedDate not supplied

Aberration of p53 and DCC in gastric and colorectal cancer.

We investigated the expression of p53 protein by immunohistochemistry and the expression of deleted in colorectal carcinoma (DCC) mRNA by the reverse transcription-polymerase chain reaction (RT-PCR) method in surgically resected tumors of gastric and colorectal cancers and compared these results to the clinicopathological features. Positive immunoreactions of p53 were observed in 21 of 42 gastric cancers (50%) and 25 of 37 colorectal cancers (67.6%). Decreased expression of DCC mRNA was observed in 15 of 38 gastric cancers (39.5%) and 10 of 28 colorectal cancers (35. 7%). There was a significant correlation between the immunoreaction of p53 and the depth of tumor invasion in gastric cancer, as well as between the decreased expression of DCC mRNA and nodal metastasis in colorectal cancer. In early cases without metastasis and invasion beyond muscularis propria, none of six gastric cancers showed a p53 immunoreaction, while seven of 9 colorectal cancers showed positive immunoreactions. On the other hand, two of 4 gastric cancers showed decreased expression of DCC mRNA; whereas, none of the seven colorectal cancers did. Alteration of p53 might occur at a later stage in gastric cancer than in colorectal cancer and be associated with the acquisition of an invasive character. In contrast to gastric cancer, decreased expression of DCC mRNA might be present in a later stage in colorectal cancer than in gastric cancer, and be related to the acquisition of metastatic character to the lymph nodes. In conclusion, alterations of p53 or DCC may play different roles in the progression of gastric cancers as compared to colorectal cancers, and the occurrence of both p53 and DCC genes mutations may cause these cancers to become more malignant.

Colorectal Neoplasms↗
PubMedDate not supplied

Arterial switch operation for transposition of the great arteries: surgical techniques to avoid complications.

From June 1984 to November 1990, 109 patients with transposition of the great arteries underwent arterial switch operation. There were 5 deaths, yielding a mortality rate of 4.6%. During this period, modifications of the surgical technique were devised to minimize intra- and postoperative problems, such as bleeding, kinking of the coronary arteries, aortic regurgitation and pulmonary stenosis. The surgical refinements that evolved include (1) a more distal division of the ascending aorta, (2) a punch technique for reimplantation of the coronary arteries in a medially rotated position, approximating the commissure, and superior to the upper border of the sinus of Valsalva, and (3) removal of left coronary ostia by incision down from the transected site to include a button of aortic wall, avoiding the free margin of the aorta and patch enlargement of the neopulmonary artery. Since instituting these refinements: (1) the time consumed for hemostasis after termination of the bypass considerably decreased from 111 +/- 59 to 87 +/- 51 minutes (p less than 0.05), (2) the incidence of kinking of the coronary arteries decreased from 29% (4/14) to 7% (6/88) (p less than 0.05), and (3) the occurrence of aortic insufficiency 1 year after correction was reduced from 36% (5/14) to 8% (5/66) (p less than 0.02). However, the occurrence of pulmonary stenosis with a pressure gradient greater than 30 mmHg did not decrease significantly despite aggressive modifications of surgical techniques, and its incidence in the most recent series of 32 patients was still a high 19%.

Aortic Valve Insufficiency↗
PubMedDate not supplied

Comparison between air CT and MRI in the detection of small acoustic neurinomas.

Air CT proved useful in yielding images of acoustic tumors as an air filling defect in 11 (24%) of 46 patients. Six of the 11 tumors were small ones of less than 1 cm in diameter. Air CT was also able to exclude an intracanalicular tumor in 29 patients (63%). MRI was performed for comparison in eight patients (nine tumors) already diagnosed by air CT as having an acoustic tumor. MRI detected eight (89%) of nine tumors. A false negative result on MRI was obtained only in one intracanalicular tumor (4.3 mm in size). This was considered to be attributable to limitations of spatial resolution including the wide slice thickness. A protocol for radiological investigation and management of patients whose clinical symptoms and/or audiovestibular examination are highly indicative of acoustic tumor is proposed and discussed.

Adult↗
PubMedDate not supplied

The impact of a comprehensive chlamydia prevention program in Wisconsin.

An analysis using case reports, laboratory records of tests for C. trachomatis, and Hospital Discharge Summary data shows that, following implementation of a chlamydia prevention program in Wisconsin in 1985, statewide declines were observed in prevalence, incidence and complications of infection. In 1990, prevalence rates among teenage women peaked at 2,794 infections per 100,000 15-19-year-old females. Between 1987 and 1991 (a period of stable testing volume), the proportion of positive tests decreased in all age-groups for females (by 29-41%) and males (by 10-14%), and the incidence of new infections in women decreased in clinic populations by 27%-50%. Between 1986 and 1991, hospitalization rates declined by 33% for pelvic inflammatory disease and by 20% for ectopic pregnancy.

Adolescent↗
PubMedDate not supplied

Primary splenic lymphoma presenting as a large cyst.

An atypical case of splenic lymphoma is presented. A large cystic mass lesion in the splenic area was found in an 80-year-old man. He was involved in a traffic accident, and subsequently the cyst ruptured. The histological diagnosis of malignant lymphoma was made at emergency splenectomy. No other lesions were identified, and there were no signs of tumor recurrence four months after the operation.

Aged↗
PubMedDate not supplied

Tranexamic acid reduces blood loss after cardiopulmonary bypass.

To evaluate the effect of tranexamic acid (TA) on blood loss after cardiopulmonary bypass (CPB), 157 patients who underwent elective valve replacement operations were studied, with one group of 90 patients receiving tranexamic acid (Group TA) and 67 patients serving as the control group (Group N). In group TA, 50 mg/kg of tranexamic acid was administered just before and after CPB, and every 90 minutes during CPB. The activated coagulation time was maintained at more than 450 seconds during CPB in both groups. There was no significant difference in the CPB time between the groups (163 +/- 32 min in group N and 152 +/- 38 min in group TA:NS). The time required for hemostasis was shortened in group TA, which resulted in a shorter operation time (6.7 +/- 1.5 hrs vs 6.0 +/- 1.5 hrs in group N and group TA, respectively: p = 0.006). The amount of chest tube drainage within 12 hours after surgery was significantly reduced (225 +/- 129 ml vs. 180 +/- 118 ml in group N and group TA, respectively: p = 0.026). The chest tube was able to be removed earlier in group TA, and the total blood loss was significantly smaller in group TA (402 +/- 292 ml) than in group N (631 +/- 609 ml; p = 0.004). The authors thus conclude that antifibrinolytic therapy during CPB with tranexamic acid reduces postoperative blood loss, and shortens the operation time due to an improvement in hemostasis.

Adult↗
PubMedDate not supplied

Effects of pump flow rate on oxygen use during moderate hypothermic cardiopulmonary bypass.

The authors investigated the effects of pump flow rate on oxygen use during a moderate hypothermic cardiopulmonary bypass (CPB) in 31 patients during either coronary artery bypass grafting or valve replacement and aortic cross clamping. Intravenous anesthesia was performed with high dose fentanyl. A neuromuscular blockade was achieved with an intravenous infusion of pancuronium. After a stable rectal temperature of 29 degrees C was obtained by both surface cooling with a blanket and core cooling with CPB, the pump flow rate was changed from 2.4 L/min/m2 to 2.2, 2.0, 1.8 and 1.6, keeping the same flow rate for at least 5 min. Both arterial and venous blood was sampled for blood gas analysis; serum lactate measurement and hemodynamic changes were monitored and recorded at each flow rate. In 10 of 31 patients, whose aortic cross clamping time was longer than 90 min, the same measurements were followed 10 min after the induction of prostaglandin E1 (PGE1) (40 +/- 13 ng/kg/min) at pump flow rates of 2.4, 2.0, and 1.6 L/min/m2. Oxygen consumption significantly decreased at 1.6 L/min/m2 compared to the other flow rates (52.4 +/- 13.6, 54.3 +/- 11.8, 56.4 +/- 14.7, and 56.7 +/- 11.0 ml/min/m2, at flow rates of 2.4, 2.2, 2.0 and 1.8 L/min/m2, respectively, versus 48.4 +/- 10.9 ml/min/m2, at 1.6 L/min/m2, p < 0.01, paired t-test). After the induction of PGE1, both aortic pressure and systemic vascular resistance decreased significantly (p < 0.01, paired t-test) at flow rates of 2.0 and 1.6 L/min/m2.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMedDate not supplied

Congenital syphilis in Maryland, 1989-1991: the effect of changing the case definition and opportunities for prevention.

BACKGROUND: The reported incidence of congenital syphilis in the United States rose dramatically during the 1980s. Although lack of prenatal care has been associated with congenital syphilis, little has been published regarding missed opportunities for prenatal intervention. GOAL OF THIS STUDY: To determine whether congenital syphilis increases in Maryland between 1989 and 1991 resulted from a true increase in congenital syphilis incidence or a change in the surveillance case definition, and to describe missed opportunities for prenatal intervention. STUDY DESIGN: This was a retrospective cohort study. RESULTS: When the revised case definition was used, a 473% increase in the number of cases was seen. Among infants who met the revised definition, 45% of mothers had received no prenatal care. Among those whose mothers had received prenatal care, opportunities to intervene were missed for 53%. CONCLUSIONS: Although a true increase in congenital syphilis incidence occurred before 1990, the increase reported in Maryland between 1989 and 1991 was primarily due to the change in case definition. Many cases of congenital syphilis could have been prevented with early and adequate prenatal care.

Adolescent↗
PubMedDate not supplied

Normal appearance of the esophagus in sagittal section; measurement of the anteroposterior diameter with ECG gated MR imaging.

Sagittal images are valuable for determining the location and local extent of esophageal tumors. However, the normal appearance of the esophagus in sagittal section has not yet been analyzed well, although there have been a few reports on normal esophagus in the axial plane. In this study, the anteroposterior (AP) diameter of normal thoracic esophagus was measured in sagittal images using ECG gated magnetic resonance (MR) imaging, and compared with that of cadavers. In 78 subjects, 222 of 234 portions (95%) were depicted well when the esophagus was divided into three portions (upper thoracic, middle thoracic, and lower thoracic and abdominal). Almost all the AP diameters (96%) were within 15-16 mm. The data correlated well with the measurements in cadavers. The AP diameter of normal thoracic esophagus in sagittal section was considered to be up to 16 mm. These results might be of clinical use to evaluate the location and extent of esophageal tumors.

Adolescent↗