Search

This paper presents micro-particle tracking velocimetry measurements over cultured bovine aortic endothelial cell monolayers in microchannels. The objective was to quantify fluid forces and cell morphology at the sub-cellular scale for monolayers subjected to steady shear rates of 5, 10, and 20 dyn/cm2. The ultimate goal of this study was to develop an experimental methodology for in vitro detailed study of physiologically realistic healthy and diseased conditions. Cell topography, shear stress, and pressure distributions were calculated from sets of velocity fields made in planes parallel to the microchannel wall. For each experiment, measurements were made in 3 h intervals for 18 h. It was found that there is a three-dimensional change in cell morphology as a result of applied shear stress. That is, cells flatten and become more wedge shaped in the stream direction while conserving volume by spreading laterally, i.e., in the cross-stream direction. These changes in cell morphology are directly related to local variations in fluid loading, i.e., shear stress and pressure. This paper describes the first flow measurements over a confluent layer of endothelial cells that are spatially resolved at the sub-cellular scale with a simultaneous temporal resolution to quantify the response of cells to fluid loading. [ABSTRACT FROM AUTHOR]

Background and purpose: Fabry disease is an X‐linked disease, and enzyme‐based screening methods are not suitable for female patients. Methods: In total, 1000 young stroke patients (18–55 years, 661 with ischaemic stroke and 339 with hypertensive intracerebral hemorrhage) were recruited. The Sequenom iPLEX assay was used to detect 26 Fabry related mutation genes. The frequency of Fabry disease in young stroke was reviewed and compared between Asian and non‐Asian countries. Results: Two male patients with ischaemic stroke were found to have a genetic mutation of IVS4+919G>A. There was no α‐galactosidase A (GLA) gene mutation in female patients. The frequency in Asian stroke patients was 0.62% (male vs. female 0.63% vs. 0.58%) with 0.72% for ischaemic stroke and none for hemorrhagic stroke, compared to 0.88% (0.77% vs. 1.08%) with 0.83% for ischaemic stroke and 1.40% for hemorrhagic stroke reported in western countries. Conclusion: IVS4+919G>A is the GLA mutation in Taiwanese young ischaemic stroke patients. Fabry disease is more frequent among non‐Asian patients compared to Asian patients. [ABSTRACT FROM AUTHOR]

Four middle-aged male Chinese with polyneuropathy, skin hyperpigmentation, oedema, hepatosplenomegaly, ascites, gynaecomastia and white nails are described. In Japan and United States this syndrome has been associated with plasma cell dyscrasia. However, neither M-protein nor skeletal lesions were demonstrated in these four patients. [ABSTRACT FROM AUTHOR]

Background: Functional outcome and the risk factors for stroke survivors have explored in previous study. However, a comprehensive understanding of the patterns and critical risk factors of functional recovery is limited., Aim: To explore the trajectory groups and determinants of functional recovery for ischemic stroke patients during 1 year after stroke., Design: Longitudinal study., Setting: Inpatient., Population: First-time stroke patients., Method: A total of 367 first-time ischemic stroke patients from the Stroke Registry in the Chang Gung Hospital (SRICH) database were analyzed in this study. Study variables comprised demographic and disease characteristics, laboratory data, and functional outcome. The Latent Class Growth Analysis (LCGA) was used to identify various trajectory clusters and multinomial logistic regression was used to identify the predictors of functional recovery., Result: Five trajectory clusters of functional recovery were identified using the Barthel Index. Among five clusters of functional recovery, nearly 18% of first-ever ischemic stroke patients maintained functional dependence, whereas 82% of stroke patients demonstrated functional recovery; and the significant recovery time totaled three months after the stroke. Determinants for various trajectory clusters of functional recovery were body mass index and serum albumin level, especially a higher serum albumin concentration predicted a more favorable functional recovery., Conclusion: Our findings suggest that diverse functional recovery clusters persisted and serum albumin concentration at admission was a critical assessment factor. CLINICAL REHABILITATION: Such information could be useful for identifying the different rehabilitation needs of varying trajectory groups and for effectively improving functional ability among the ischemic stroke population.

Background and Purpose: Musical murmurs (MMs), sometimes called seagull cry, goose cry, honks, or cooing murmur, are murmurs with a single frequency that sounds like a musical tone. Doppler detections usually show mirror-image parallel strings or bands of low to moderate frequency. Musical murmurs are mostly described in cardiac murmurs and have seldom been mentioned in cerebrovascular disease., Methods: A retrospective review of 12,000 patients from our neurosonographic data base of the past 7 years was conducted to find patients who had MMs during color-coded carotid and transcranial duplex sonographies., Results: Sixty-six musical murmurs were found in 60 patients (0.5% of all studied patients). There were 44 men and 16 women with a mean age of 63.8 years. Musical murmurs may occur with or without simultaneous turbulent flows, or very close to a high-intensity frequency (with systolic spindles) turbulent flow. Musical murmurs are detected more frequently in intracranial vessels (94%) than in extracranial cervical arteries. The pathologic changes corresponding to the area of MMs were high-grade stenosis of the arteries (58 MMs), small arteries serving as collateral circulation (5 MMs), carotid cavernous sinus fistulas (2 MMs), and Moyamoya disease (1 MM). Fifty (88%) of 57 patients with stenotic arterial lesions had histories of cerebral infarction or transient ischemic attack, and 64% of the cerebrovascular events occurred on the side appropriate to the MMs., Conclusions: The presence of MMs in color-coded carotid duplex and transcranial color-coded duplex sonography imply severe underlying vascular diseases that require prompt treatment. Further cerebral angiographic study is warranted to clarify the underlying pathology in patients with MMs.

Little is known of the association of enterohemorrhagic Escherichia coli O157:H7/NM (EHEC O157) with disease in naturally infected calves, although cattle have been known as a major source for EHEC O157 outbreaks in humans. In this study, we investigated the occurrence of EHEC O157 in calves associated with/without diarrhoea to examine if EHEC O157 is involved in calf diarrhoea and to characterize the isolates. Four hundred and ninety eight diarrhoeic and non-diarrhoeic young calves from 115 different farms were examined. Of 244 diarrhoeic calves, 24 (9.8%) were positive for EHEC O157, and of 254 non-diarrhoeic calves, 7 (2.8%) were positive. EHEC O157 was recovered from 12/76 (15.79%) of diarrhoeic calves less than 2-week-old, and no EHEC O157 was detected in this age group of non-diarrhoeic calves. This implicates EHEC O157 as a possible cause of the disease in naturally infected neonatal calves. The occurrence of EHEC O157 was relatively lower in the older calves (aged older than 8 weeks) and no significant difference was found in the occurrence rates between these diarrhoeic and non-diarrhoeic calves. PCR analysis of virulence markers revealed that the isolates carried various virulence genes such as Ehly, eae, stx1 and stx2, which underlines the potential importance of these attributes for the infection, colonization and possible pathogenesis of calf diarrhoea.

We report for the first time upon a case of myxoma that involved both atrial and ventricular sides of the anterior mitral valve leaflet. Electron beam tomography (EBT) showed that the tumor was attached to both the atrial and ventricular sides of the mitral valve, while echocardiography did not. EBT also diagnosed dynamic obstruction of left ventricular outflow tract caused by the tumor.

Although primary cardiac lymphoma was a near fatal disease in the past, recent advances in imaging diagnosis and chemotherapy have dramatically improved survival. We describe the CT and MR findings of primary cardiac lymphoma in two immunocompetent subjects who recovered after chemotherapy. The primary cardiac lymphomas manifested as a poorly enhancing mass on CT, relatively hyperintense on a T2-weighted image and a heterogeneously enhanced mass on contrast-enhanced MR. The tumor also showed a predilection for right heart chambers and contiguous infiltration along adjacent structures.

Purpose: The authors' goal was to assess the diagnostic accuracy and clinical effect of MRI compared with echocardiography and catheterization in the evaluation of cardiac defects with situs ambiguous., Method: Twenty-two patients with visceral heterotaxy syndrome were included., Results: Because situs determined by the relation between the pulmonary artery and bronchi showed most predominantly a tendency toward lateralization, this was regarded as the standard reference of situs determination. For the purpose of this study, patients were classified as having right isomerism (n = 13) or left isomerism groups (n = 9). MRI has several advantages compared with echocardiography or cardiac angiography for examining patients with situs ambiguous. (1) The bronchial, pulmonary arterial, and splenic situs can be readily determined, and discrepancies (n = 2) can be assessed easily. (2) Venoatrial connections are adequately imaged. In particular, all types of total and partial anomalous pulmonary venous return are delineated, regardless of whether restrictions of pulmonary blood flow or pulmonary venous obstructions are involved (n = 4). The courses of vertical veins were easily identified, and the prearterial position was revealed in only one of seven right isomerisms with total anomalous pulmonary venous return. The drain pattern of the hepatic vein can be visualized using three-dimensional spatial information and is useful for total cavopulmonary connection design. (3) Associated complicated cardiac anomalies, particularly the size or peripheral stenosis of the pulmonary arteries, may be evaluated, and this information is useful for palliative shunt operations., Conclusion: Because of its wide field of view and imaging, which is not restricted by associated anomalies, a thorough understanding of the cardiovascular anatomy of the situs ambiguous can be achieved using MRI, which is of considerable value in the surgical correction of this complicated anomaly. MRI can obviate or facilitate catheterization in these critically ill patients.

A novel glucanhydrolase from a mutant of Lipomyces starkeyi ATCC 74054 was purified. The single protein (100 kDa) showed either dextranolytic or amylolytic activity. We referred to the glucanhydrolase as a DXAMase. The DXAMase was produced in a starch medium and it was 3.75-fold more active for hydrolysis of the purified insoluble-glucan of Streptococcus mutans than Penicillium funiculosum dextranase. Aggregation of S. mutans cells with dextran and adherence to glass were eliminated by incubating with the DXAMase. The addition of DXAMase (0.1 IU/ml) to the mutansucrase reaction digest with sucrose reduced the formation of insoluble-glucan about 80%. Also the DXAMase (0.5 IU/ml) removed 80% of the pre-formed sucrose-dependent adherent film. These in vitro properties of L. starkeyi KSM 22 DXAMase are desirable for its application as a dental plaque control agent.

Bronchogenic cysts are generally found in the mediastinum, particularly posterior to the carina, but they rarely occur in such unusual sites as the skin, subcutaneous tissue, pericardium, and even the retroperitoneum. A 30-year-old Korean man underwent surgery to remove a cystic adrenal mass incidentally discovered during routine physical checkup. At surgery, it proved to be a multilocular cyst located in the retroperitoneum adjacent to the left adrenal gland. Microscopically, the cyst was lined by respiratory epithelium over connective tissue with submucous glands, cartilage and smooth muscle, thereby histologically confirming bronchogenic cyst. This is the first reported case of retroperitoneal bronchogenic cyst in an adult without other congenital anomalies in Korea.

Impairment of higher cortical functions is usually not considered as a typical presentation of lacunar infarction. However, a small discrete lesion at strategically important locations may produce memory loss and mental changes. We report 4 patients with lacunar infarctions manifested as acute amnesia and mental changes. One patient had left thalamic infarction, one had left capsular genu infarction, one had right capsular genu infarction, and one had left capsular genu infarction extending to the ipsilateral thalamus. The mental and memory impairment was transient in one patient but was persistent in the other 3 patients. Our report reconfirms that a lacunar infarction can cause impairment of higher cortical functions.

Meningococcal meningitis is one of the most common bacterial infections of the meninges worldwide, and tuberculous infection is the most common cause of chronic meningitis in Taiwan. However, mixed meningococcal and tuberculous meningitis is rare. We describe a 27-year-old woman with a case of culture-proven meningococcal and tuberculous meningitis verified by polymerase chain reaction on a cerebrospinal fluid specimen. The patient was initially treated with intravenous antibiotics including penicillin G and chloramphenicol. Though the patient responded well to therapy initially, her subsequent clinical deterioration was finally controlled by long-term antituberculous medications.

The authors describe 2 patients with multiple cerebral infarcts and hemorrhagic transformation caused by artery-to-artery emboli. Ulcerated plaques with free-floating thrombus adherent to the plaque were detected at the carotid bifurcation by duplex sonography. No other embolic source could be found. One patient developed an occipital infarction due to carotid emboli passing through a fetal-type posterior communicating artery. Both patients recovered well without recurrence of stroke or transient ischemic attack with antiplatelet treatment only. Follow-up carotid duplex sonography showed disappearance of floating thrombus in 1 patient and consolidation of the lesion in the other.

A forty-six year-old premenopausal woman developed headache, nausea and vomiting, left hemiparesis and seizure two days after parenteral use of progesterone and estradiol. Diabetes mellitus (DM) was found during admission. Computed tomography showed a hemorrhagic infarct in the right frontal lobe and increased density in the superior sagittal sinus (SSS). Left carotid angiography found occlusion of the left internal carotid artery (ICA). Right carotid angiograms failed to show the SSS and inferior sagittal sinus, suggestive of venous sinus thrombosis. Coexistence of the cerebral artery and the venous sinus occlusion has been described infrequently. In this case, the authors postulate that the use of estradiol and progesterone and the underlying DM increased vascular thrombogenicity, which provided a common denominator for thrombosis of both the ICA and the venous sinus.

Background: Transient ischemic attack (TIA) is recognized as a precursor of cerebral infarction. It is prompted by an embolism from extracranial carotid artery disease. However, extracranial carotid disease is less prevalent in Chinese patients. Non-invasive duplex sonography has been used for initial screening for extracranial carotid artery disease., Methods: One hundred and twenty-seven consecutive patients with carotid TIA were divided into two groups according to sonographic results, Group I: < or = 50%, and Group II: > 50% stenosis of the carotid artery. The two groups were compared for the clinical manifestations, risk factors, brain computed tomography (CT) findings and subsequent stroke. An age and sex-matched group of patients with lacunar stroke was also collected from the same neurosonological data bank for further comparative analysis., Results: The mean age at onset was 59 +/- 12 (mean SD) years. Hypertension was the most common risk factor. The most common symptom was transient focal motor deficit (73%) with or without other complaints. Eighty-two percent of the TIA episodes were less than one hour in duration. In Group I, there were 114 patients (90%) with stenosis < or = 50% ipsilateral to the symptomatic side. Group II included only 13 patients (10%) with the ipsilateral carotid artery stenosis > 50%. Mean age was older and cigarette smoking was more common in Group II (p < 0.05). Otherwise, no significant difference was noted between the two groups in initial characteristics of TIAs, risk factors, brain CT findings or subsequent stroke. Further, there was no statistical significant difference between the TIA and lacunar stroke groups in the degree of carotid stenosis., Conclusions: Hypertension was the most common risk factor for carotid TIAs. The prevalence of extracranial carotid artery disease was low in Chinese patients with carotid TIAs. The severity of the carotid artery was not predictive of recurrence of TIA or of subsequent stroke. There was no significant difference between patients with TIA and with lacunar stroke in sonographic findings of extracranial carotid arteries.

We have performed transcranial color-coded sonography to 150 normal adults. Through the temporal, orbital and foraminal windows, by using a 2 MHz pulsed-wave transducer, we were able to directly insonate the brain parenchyma, and to obtain color-coded Doppler vascular imagings and flow velocities of the intracranial basal cerebral arteries. There was no significant difference of blood flow velocities and resistance index between the right and left hemispheres. The mean velocities was highest in the middle cerebral artery and lowest in the ophthalmic artery while which had the highest resistance index. Female had higher mean velocity in basilar artery. The mean velocity, peak systolic velocity, as well as end diastolic velocity decreased significantly with age in middle cerebral artery, anterior cerebral artery and basilar artery. Four illustrative cases with abnormal findings were presented to compare with normal control. Some pitfalls in ultrasonography were also described.

Purpose: To demonstrate the efficacy of carotid duplex ultrasound to diagnose common carotid artery occlusion (CCAO) and to define the clinical features of CCAO., Methods: We reviewed 5400 carotid duplex ultrasonograms obtained over a 7-year period for suspected carotid artery disease. In cases of CCAO, medical records were reviewed., Results: Thirteen cases (0.24%) of CCAO were diagnosed by carotid duplex ultrasonography, including five cases of isolated CCAO. Seven cases were proved by cerebral angiography. Cerebral angiography failed to demonstrate patent internal carotid arteries in two cases of isolated CCAO. Mean age of onset was 67 +/- 9 years. The main clinical presentation was stroke in nine cases (69%). The most common vascular risk factors were hypertension (62%) and heart diseases (54%). Three patients had a history of radiation therapy to the neck. Two of five patients with isolated CCAO had major stroke, with good recovery in one, whereas five of eight patients with CCAO had major stroke; among them, only one had good recovery., Conclusion: Patients with isolated CCAO may have a better outcome than patients with CCAO. Duplex sonography, particularly with color-coded flow imaging, provides an accurate examination to define the patency of the arteries distal to the carotid bifurcation. The clinical features of CCAO are similar to those of internal carotid artery occlusion except for the low prevalence of CCAO.

A 62-year-old diabetic women developed acute quadriparesis. Her first symptom was clumsiness of the right limbs, which was followed shortly after by quadriparesis with severe left-sided symptoms. Sensory examination showed pinprick and thermal sensation deficits below the left T6 and right T8 dermatomes. An intramedullary infarction in the cervical cord at C5 to C6 levels was demonstrated by serial magnetic resonance imaging (MRI) studies with Gadolinium-DTPA (Gd-DTPA) enhancement. Based on the findings from this patient and 20 patients with spinal cord infarction reported in the literature, it was concluded that spinal cord infarct lesions are characterized by negative Gd-DTPA enhancement at the acute and chronic stages and positive enhancement at the subacute stage, 1 to 4 weeks after the onset of infarction.

Phenylpropanolamine (PPA) is the major ingredient of many over-the-counter cold remedies and diet pills. Use or abuse of PPA may cause hemorrhagic stroke or cerebral vasculitis similar to the clinical and angiographic picture associated with amphetamine use or abuse. We report a 32-year-old Taiwanese women who developed sudden onset of severe headache, nausea and vomiting on the seventh day of oral ingestion of 75 mg PPA per day. Cerebral angiograms showed multiple areas of alternating focal constriction and dilatation ("beading" appearance) in the anterior and posterior cerebral arteries consistent with cerebral arteritis. This case should alert medical practitioners to the potential hazards of over-the-counter drugs like PPA.

Five cases of unilateral intracranial internal carotid artery (ICA) occlusion received both carotid angiographic and ultrasonographic studies. The Doppler examination showed that the resistive index (RI) of the common carotid artery (CCA) and ICA was higher but the peak systolic velocity was lower on the diseased side as compared with the normal side. Absence of the diastolic phase was found in the CCA flow in 2 cases and in the ICA flow in 3 cases on the diseased side. The mean CCA flow volume on the diseased side (271 +/- 82 mL/min) was half or less than that on the normal side (680 +/- 86 mL/min) (P < 0.01). The flow volume of the diseased ICA (49 +/- 20 mL/min) was markedly lower than that of the normal side (344 +/- 49 mL/min) (P < 0.01) and was also less than that of the ipsilateral external carotid artery (ECA) (129 +/- 43 mL/min). The Doppler ophthalmic artery flow all showed a forward direction. The authors propose that the following extracranial carotid ultrasonographic findings may be helpful in the prediction of intracranial carotid artery occlusion: (1) diminished frequencies, increased RI, and a more than 50% reduction of flow volume in the CCA as compared with the opposite side; (2) diminished frequencies to loss of the diastolic phase, a more than 50% reduction of the flow volume, and reversed ICA/ECA flow volume in the ICA as compared with the opposite side; and (3) a forward Doppler ophthalmic artery flow.

The authors report 2 cases of common carotid artery (CCA) occlusion and 4 cases of extracranial internal carotid artery (ICA) occlusion with forward Doppler ophthalmic artery flow. The compression test during Doppler study showed that the ophthalmic artery flow was reduced to zero when compressed contralateral to the CCA in 1 case of CCA occlusion and when compressed ipsilateral to the CCA in all 4 cases of ICA occlusion. The angiograms showed that in the 2 cases of CCA occlusion, 1 had the ophthalmic artery originating from the anterior communicating artery, and the other had subclavian steal syndrome with a reversed vertebral flow. In 3 of the 4 cases of ICA occlusion, the ophthalmic artery was found to originate from the ipsilateral middle meningeal artery. Their findings suggest that in cases of extracranial carotid artery occlusion, the forward ophthalmic artery flow is supplied from the contralateral CCA in cases of CCA occlusion and from the branches of the ipsilateral external carotid artery in cases of ICA occlusion, and the vertebrobasilar system plays a less important role.

Comparison between sonographic and angiographic findings of the extracranial carotid arteries were made in 68 patients. We used a Diasonic Duplex Ultrasonograph (DRF 400) which combined a real-time B-mode imaging system and a pulsed-wave Doppler spectral analyser. Continuous-wave Doppler was also used to determine ophthalmic artery flow direction. The findings were classified into four categories: (1) normal or less than 10% stenosis, (2) 10-49% stenosis, (3) 50-99% stenosis, (4) and total occlusion. The agreement between the two tests was 0.53 which meant fair agreement beyond chance by Kappa statistics. When angiograms were used as gold standard, the sensitivity of duplex sonography was above 80% in all categories of stenosis, and the overall accuracy and specificity were above 90% in those stenosis greater than 50% and occlusion. We conclude that duplex sonography, a reproducible noninvasive test, is a safe and cost-efficient screening method which can provide a good correlation with angiograms in detecting extracranial carotid artery disease.

To determine the diagnostic accuracy of extracranial internal carotid artery (ICA) occlusion by carotid duplex sonography and ophthalmic flow direction, we compared both carotid sonograms and angiograms in 82 cases of ischemic cerebrovascular disease. A total of 157 carotid arteries were available for comparison. The overall diagnostic accuracy of ICA occlusion by duplex scanning was 96% (sensitivity, 83%; specificity, 98%; positive predictive value, 91%), by ophthalmic flow examination, 95% (sensitivity, 79%; specificity, 98%; positive predictive value 86%), and by combined study, 98% (sensitivity, 96%; specificity, 98%; positive predictive value 92%). We recommend that the ophthalmic flow examination should be used in combination with other sonographic methods in detecting extracranial carotid artery disease. The combined study gives higher diagnostic accuracy than the single method. When an occlusion or a tight stenosis is uncertain on carotid sonograms, color Doppler or angiography is indicated for further confirmation.

A 40-year-old normotensive man suddenly developed dizziness, vomiting, hoarseness and swallowing disturbance. Neurologic examinations showed bilaterally decreased palatal elevation and gag reflex, upbeat nystagmus and gait ataxia. The diagnosis of medullary hemorrhage was first established by computed tomography (CT). Magnetic resonance imaging study further showed a hematoma in the paramedial medulla oblongata extending dorsorostrally to the pontomedullary junction. It gave the precise anatomic boundary of the intramedullary hematoma and was well correlated with the clinical findings. This patient's subsequent prognosis was good with gradual improvement of the clinical signs and symptoms. A follow-up CT scan showed resolution of the hematoma, and the prognosis was consistent with a good neurologic recovery.