bluuebunny/crossref_metadata_2025 huggingface dataset:
Biological Effects of Oxidant Stress in Haemodialysis: The Possible Roles of Vitamin E
Authors: Galli Francesco , Canestrari Franco , Buoncristiani Umberto
Published: April 2003

Oxidative stress has been proposed to play a role in many disease states, including cardiovascular and infectious diseases, cancer, diabetes and neurodegenerative pathologies. The fact that these diseases have an increased incidence in uremia, and particularly in dialysis patients, suggests an increased exposure to oxidative stress in this condition. In haemodialysis (HD), the absence of a complete correction of the uremic toxicity together with the untoward effects of the dialysis, malnutrition and the progressive worsening of the clinical condition, can lead to a high susceptibility to oxidative stress by an abnormal production of oxidants – including reactive oxygen species (ROS) and uremic toxins with prooxidant function – and defective antioxidant protection. One of the most investigated biological effects of the oxidative stress in the HD patients is lipid peroxidation in plasma and blood cell membranes. Moreover, we have recently described how abnormal apoptosis in peripheral blood leukocytes is associated with cell oxidative stress (intracellular thiol depletion). Vitamin E, in both in vitro and in vivo conditions, has been proposed to partially correct these effects. In this review we evaluated some features of two new dialysis strategies using an antioxidant approach to the protection against the oxidant stress in HD. Their rationale is based on the emerging role of vitamin E in counteracting some biological effects associated with oxidant stress namely lipid peroxidation and apoptosis. These techniques use: 1) the recirculation of the dialysate through a suspension of vitamin E-enriched liposomes combined with the supplementation by the dialysate with ascorbic acid, this method has been called hemolipodialysis; 2) the coating of the dialysis membrane with vitamin E (vitamin E- modified dialysis membranes). These unconventional approaches to the antioxidant therapy in HD open a widely unexplored and promising field in the evolution of the biomaterials and dialysis quality.
Cytokine Production in Haemodialysis
Authors: Memoli B.
Published: April 2003

Many aspects regarding morbidity and mortality of dialysis patients are related to the production of cytokines by peripheral blood mononuclear cells. Clinical alterations resulting from cytokine production and release may include dialysis amyloidosis, malnutrition and atherogenesis. Cytokine release may also play a relevant role in immunodeficiency of dialysis patients by inducing alterations in immune and host-defense system. Interleukin-1, interleukin-6 and tumor necrosis factor are three pro-inflammatory cytokines, mainly produced by monocytes, and involved in pathogenetic aspects of hemodialysis-related diseases. In this review we analyse the mechanisms underlying monocyte activation and describe the different modalities for studying cytokine production and release. Clinical implications of cytokine production are also discussed.
Impaired Biological Activity of Erythropoietin by Cyanate Carbamylation
Authors: Mun Kyo-Cheol , Golper Thomas A.
Published: April 2003

Aims: During advanced renal failure, particularly in patients with end-stage renal disease (ESRD), proteins are carbamylated as a result of a reaction with cyanate. Some or all of the cyanate is derived from urea. If the carbamylation of proteins adversely alters their biologic activities, then urea must be viewed as an uremic toxin, rather than a surrogate. Therefore, we studied the effect of cyanate carbamylation on the erythropoietic activity of erythropoietin (EPO) in a rodent model. Methods: EPO was carbamylated by incubation with cyanate at 37°C. The extent of carbamylation was monitored using trinitrobenzenesulfonic acid. In Sprague-Dawley rats the erythrocyte count, hemoglobin concentration, and hematocrit were measured after the twice-weekly subcutaneous injection of either EPO or carbamylated EPO for 3 weeks. Two additional control groups received physiologic saline or 0.2 ml of 1 M cyanate. Results: The level of carbamylated EPO was increased as the time of exposure to cyanate increased from 1 to 6 h, and as the cyanate concentration increased from 8 to 2,000 mM. EPO injections caused significantly large increases in all erythropoietic measures. Physiologic saline or 1 M cyanate-injected controls and the carbamylated EPO-injected animals demonstrated no change from baseline in erythropoietic parameters. Conclusion: These results support that EPO exposed to high levels of cyanate in vitro demonstrates diminished biologic activity in healthy Sprague-Dawley rats. This effect may be manifested by the carbamylation of EPO by the cyanate. Should this occur in ESRD patients, it may contribute to the suboptimal erythropoietic response to EPO therapy associated with high urea levels, especially related to inadequate dialysis. Targeting dialysis doses specifically to urea concentrations may be more important than previously considered.
Chronic Inflammation in Hemodialysis: The Role of Contaminated Dialysate
Authors: Lonnemann Gerhard
Published: April 2003

Routine sodium bicarbonate-buffered dialysate is contaminated with predominantly gram-negative micro-organisms. These bacteria release pyrogenic substances such as endotoxins, peptidoglycans, exotoxins and fragments thereof. Pyrogens derived from contaminated dialysate either alone or in costimulation with activated complement components are the most important activators of circulating mononuclear cells in patients on chronic intermittent hemodialysis. Activated mononuclear cells release proinflammatory cytokines which are key mediators in acute and chronic inflammatory diseases associated with long-term hemodialysis therapy. Recent experimental and clinical data suggest that the use of pyrogen-free dialysate prevents activation of mononuclear cells and improves the state of chronic inflammation, as indicated by decreased plasma levels of C-reactive protein in chronic hemodialysis patients. Future clinical studies have to prove whether the use of pyrogen-free dialysate in combination with biocompatible dialyzer membranes and tubings reduces the incidence and severity of chronic inflammatory diseases (β2-microglobulin amyloidosis, muscle protein wasting, atherosclerosis) in long-term hemodialysis patients.
Cloning, mapping and expression analysis of VPS33B, the human orthologue of rat Vps33b
Authors: Carim L. , Sumoy L. , Andreu N. , Estivill X. , Escarceller M.
Published: April 2003

We have identified VPS33B, the human ortholog of rat Vps33b. VPS33B encodes a transcript of 2482 nt with an ORF of 617 amino acids and a predicted protein size of 70.6 kDa. VPS33B contains a Sec-1 domain shared with a family of proteins involved in protein sorting and vesicular trafficking. Enriched expression of VPS33B was observed in testis. VPS33B was positioned at chromosome 15q26.1 by radiation hybrid mapping.
DNA hypomethylation and unusual chromosome instability in cell lines fromICF syndrome patients
Authors: Tuck-Muller C.M. , Narayan A. , Tsien F. , Smeets D.F.C.M. , Sawyer J. , Fiala E.S. , Sohn O.S. , Ehrlich M.
Published: April 2003

The ICF syndrome (i̲mmunodeficiency, c̲entromeric region instability, f̲acial anomalies) is a unique DNA methylation deficiency disease diagnosed by an extraordinary collection of chromosomal anomalies specifically in the vicinity of the centromeres of chromosomes 1 and 16 (Chr1 and Chr16) in mitogen-stimulated lymphocytes. These aberrations include decondensation of centromere-adjacent (qh) heterochromatin, multiradial chromosomes with up to 12 arms, and whole-arm deletions. We demonstrate that lymphoblastoid cell lines from two ICF patients exhibit these Chr1 and Chr16 anomalies in 61% of the cells and continuously generate 1qh or 16qh breaks. No other consistent chromosomal abnormality was seen except for various telomeric associations, which had not been previously noted in ICF cells. Surprisingly, multiradials composed of arms of both Chr1 and Chr16 were favored over homologous associations and cells containing multiradials with 3 or >4 arms almost always displayed losses or gains of Chr1 or Chr16 arms from the metaphase. Our results suggest that decondensation of 1qh and 16qh often leads to unresolved Holliday junctions, chromosome breakage, arm missegregation, and the formation of multiradials that may yield more stable chromosomal abnormalities, such as translocations. These cell lines maintained the abnormal hypomethylation in 1qh and 16qh seen in ICF tissues. The ICF-specific hypomethylation occurs in only a small percentage of the genome, e.g., ICF brain DNA had 7% less 5-methylcytosine than normal brain DNA. The ICF lymphoblastoid cell lines, therefore, retain not only the ICF-specific pattern of chromosome rearrangements, but also of targeted DNA hypomethylation. This hypomethylation of heterochromatic DNA sequences is seen in many cancers and may predispose to chromosome rearrangements in cancer as well as in ICF.
Different Vascular Risk Factor Profiles among Cortical Infarcts, Small Deep Infarcts, and Primary Intracerebral Haemorrhage Point to Different Types of Underlying Vasculopathy
Authors: Schmal M. , Marini C. , Carolei A. , Di Napoli M. , Kessels F. , Lodder J.
Published: April 2003

The type of small-vessel disease in small deep (lacunar) infarcts (SDIs) remains contentious as opposed to that in primary intracerebral haemorrhage (PICH), which is lipohyalinosis in most cases. Therefore, we compared risk factor profiles as indicators of underlying vessel pathology, between patients with SDI and patients with PICH, and those with a non-cardio-embolic infarct involving the cortex (CORTI). Multivariate regression analysis showed that diabetes mellitus [odds ratio (OR) 0.56; 95% confidence interval (CI) 0.34–0.90] and hypercholesterolaemia (OR 0.63; 95% CI 0.40–0.99) were more strongly associated with CORTI than with SDI. Carotid stenosis was associated with SDI in comparison with PICH (OR 7.5; 95% CI 1.02–54.94). Compared with PICH, CORTI was more strongly associated with diabetes mellitus (OR 3.27; 95% CI 1.38–7.76), carotid stenosis (OR 24.42; 95% CI 4.99–119.45), and hypercholesterolaemia (OR 3.12; 95% CI 1.47–6.65), whereas hypertension was associated with PICH (OR 0.37; 95% CI 0.18–0.79). These data support the hypothesis that small-vessel atheromatosis rather than small-vessel lipohyalinosis underlies lacunar infarcts in most cases.
Cerebral Venous Thrombosis Complicated by Hemorrhagic Infarction: Factors Affecting the Initiation and Safety of Anticoagulation
Authors: Wingerchuk Dean M. , Wijdicks Eelco F.M. , Fulgham Jimmy R.
Published: April 2003

Background and Purpose: Anticoagulation (AC) may improve outcome in cerebral venous thrombosis (CVT), even when complicated by pretreatment hemorrhagic infarction (HI). The HI characteristics which affect the decision to initiate AC therapy and its outcome are unknown. We reviewed our experience with AC treatment for patients with CVT and HI. Methods: Retrospective study. Results: Two groups of patients were compared: those who received AC (n = 6) and those who did not (n = 6). Hemorrhage volumes ranged from petechial to large (93 cm3) hematoma with mass effect. Anticoagulated patients received treatment a mean of 11.3 days after symptom onset. Each had exclusively extratemporal HI without midline shift and had stable hemorrhage volumes and clinical status for at least 24 h prior to AC. AC did not increase HI volume or worsen clinical outcome. All 6 non-AC patients had enlarging hematomas. Four of these 6 patients had temporal HI; and two required hematoma resection. Conclusions: AC therapy was avoided in CVT patients with HI that were located in the temporal lobe, caused midline shift or were enlarging. AC was safely initiated within several days in clinically stable patients with non-temporal-lobe HI of unchanging volume. We suggest that the location and unchanged volume on serial CT may be important factors influencing the safety of AC therapy in patients with CVT and HI.
Autonomic Nervous Activity during Sleep in Middle Cerebral Artery Infarction
Authors: Giubilei Franco , Strano Stefano , Lino Stefano , Calcagnini Giovanni , Tisei Paolo , Fiorelli Marco , Ferretti Cinzia , Cerutti Sergio , Fieschi Cesare
Published: April 2003

No data are available on the autonomic system during sleep in patients with stroke. The purpose of this study was to determine the influence of acute ischemic stroke on the autonomic cardiovascular system during sleep, and to correlate autonomic activity with the clinical status of patients. Ten patients with ischemic stroke in the middle cerebral artery were studied by means of an all-night polysomnographic recording within the 1st week of the onset of symptoms and at the 3-week follow-up examination. Power spectrum analysis of the heart rate variability was performed using an autoregressive algorithm in 180 consecutive electrocardiographic RR intervals. Spectral power was calculated in 3 main frequency bands: high frequency (HF), 0.15–0.4 Hz; low frequency (LF), 0.04–0.15 Hz; very low frequency (VLF), <0.04 Hz. The data were compared with those of 10 age-matched controls. A significant increase in VLF (p < 0.0005) and a decrease in HF (p < 0.0002) components were found in ischemic stroke patients. The sympathetic-parasympathetic balance (VLF + LF/HF) was higher in patients than controls (p < 0.005). However, these components changed significantly during sleep, revealing a physiological pattern. These power spectral data were still present at the 3-week follow-up. The 4 patients who developed cardiac arrhythmias showed higher sympathetic-parasympathetic balance than patients without arrhythmias (p < 0.05). These data suggest a sympathetic predominance in patients with acute ischemic stroke during sleep. However, the flexible and dynamic properties of the autonomic nervous system are preserved. Cardiac arrhythmias following stroke may be related to the degree of sympathetic predominance.
Influence of Clinical Factors, CT Findings and Early Management on Outcome in Supratentorial Intracerebral Hemorrhage
Authors: Hårdemark H.-G. , Wesslén Nils , Persson Lennart
Published: April 2003

Background and Purpose: Treatment of supratentorial intracerebral hemorrhage (SICH) is still controversial and new adequately sized randomized controlled trials (RCTs) of surgical evacuation are greatly needed. Our aim was to identify and quantify the most important clinical and CT factors related to prognosis in patients with SICH, to estimate the treatment effect in various subpopulations of surgically treated patients and to make assumptions on target population and sample size in future trials. Methods: Uni- and multivariate analysis of retrospectively collected data on clinical and CT factors on admission and early management in 203 patients with SICH, mortality at discharge, 30 days, 6 and 12 months and clinical outcome according to the modified Rankin Scale (mRS) at 6 months and follow-up at a mean of 3.1 years after admission. Results: Level of consciousness according to the Glasgow Coma Scale (GCS) and age were the single two factors best related to mortality at 6 and 12 months. GCS and age, in association with hematoma volume and location, arterial hypertension and to some extent use of steroids, were also related to clinical outcome according to the mRS at 6 months and 3.1 years. Surgical evacuation seemed to have a positive effect on clinical outcome in only a small subgroup of the patients. Conclusions: Our data support a future RCT of surgical evacuation versus conservative treatment in SICH restricted to patients younger than 60–65 years with a GCS on admission in the range of 6–11 and a hematoma not mainly located in the thalamus with a volume in the range of 30–100 ml causing a midline shift of less than 10 mm. Randomization should be balanced within groups of patients with lobar and basal ganglion hematomas, arterial hypertension and intraventricular hemorrhage, and the use of steroids should be discouraged.
Recurrence of Bleeding in Patients with Hypertensive Intracerebral Hemorrhage
Authors: Bae Hack-Gun , Jeong Du-Shin , Doh Jae-Won , Lee Kyeong-Seok , Yun Il-Gyu , Byun Bark-Jang
Published: April 2003

To characterize the recurrence of bleeding in patients who had hypertensive intracerebral hemorrhage (HICH), the authors reviewed 989 patients who underwent treatment for HICH between 1989 and 1995. Fifty-three patients (5.4%) had two episodes of HICH within a median interval of 22.9 ± 16.3 months (range 1.5–72 months), and of these 3 (5.7%) had three episodes of HICH. The recurrence of bleeding most commonly occurred within 2 years of the first hemorrhage: in 66% of the 53 patients the second hemorrhage occurred soon after the first (within 1 year in 34%, within 1–2 years in 32.1%). The site of the second hemorrhage was different from the initial site in all patients. Only 1 patient had a third hemorrhage in the same site as the second hemorrhage. The common patterns of recurrence were ‘ganglionic (putamen/caudate nucleus)-thalamic’ in 26.8% and ‘ganglionic-ganglionic’ in 21.4%. The ‘lobar-lobar’ pattern was noted in only 2 patients. The volume of the hematoma was increased at the second hemorrhage. The overall mortality was 28.3%. The risk of recurrent hemorrhage significantly increased in the patients who had antihypertensive therapy of less than 3 months after the initial attack compared to those with further long-term therapy (p < 0.005). Long-term regular control for hypertension is needed to prevent recurrent hemorrhage.
Protein S Deficiency, Activated Protein C Resistance and Sticky Platelet Syndrome in a Young Woman with Bilateral Strokes
Authors: Chaturvedi Seemant , Dzieczkowski Jeffery S.
Published: April 2003

Background: Coagulation disorders are common in young adults (age less than 55 years) with ischemic stroke. Objectives: To describe a young woman with bilateral strokes of undetermined etiology who had three significant hemostatic disturbances. These were protein S deficiency, Factor V Leiden heterozygosity, and sticky platelet syndrome. The Factor V Leiden mutation was also present in one of her children. Conclusions: Young patients with cryptogenic stroke warrant a thorough evaluation for hypercoagulable states. More than one coagulation disorder can coexist in the same patient and the spectrum of hemostatic abnormalities may influence the patient’s treatment and may have implications for screening of other family members.
Impaired Vasoreactivity of the Basilar Artery System in Patients with Brainstem Lacunar Infarcts
Authors: Panczel Gyula , Bönöczk Peter , Voko Zoltan , Spiegel Dagmar , Nagy Zoltan
Published: April 2003

Background and Purpose: Diminished vasoreactivity (VR) has been evidenced in patients with hemispheric small vessel disease, however, there is no data regarding vertebrobasilar (VB) territory VR changes in patients with subcortical vascular encephalopathy located in the brainstem. Therefore, we compared the cerebral blood flow velocity (CBFV) responses of the VB system during different vasoregulatory challenges in healthy volunteers to those in patients with brainstem lacunar infarcts. Methods: In 20 patients with brainstem lacunar infarcts and in 10 healthy volunteers the VR of the VB system was measured by analyzing the CBFV changes during different stimulation paradigms (ventilation, tilting and acetazolamide tests). During transcranial Doppler registration the systemic blood pressure and the expiratory partial CO2 pressure were monitored. Results: During hypercapnia the VR was significantly higher in the control group than in the patient group (10.1 ± 4.9 vs. 3.4 ± 5.0 cm/s/kPa, p = 0.0025). In a subgroup of patients with mean baseline CBFV <25 cm/s the VR was 1.5 ± 2.4 cm/ s/kPa, while patients with mean baseline CBFV >25 cm/s showed a significantly higher value (7.8 ± 6.9 cm/s/kPa). Furthermore, in patients with mean baseline CBFV <25 cm/s the pulsatility index was significantly higher than in patients with mean baseline CBFV >25 cm/s (1.11 ± 0.26 vs. 0.86 ± 0.19, p = 0.0325), reflecting significantly higher vascular resistance in the former group. Although CBFV measurements during tilting and acetazolamide tests tended to support these findings, they showed no significant differences between patients and controls. Conclusion: Patients with cerebral microangiopathy involving the brainstem showed impaired VR in the VB flow territory in association with baseline CBFV.
Clinical Features and Prognosis in Young Adults with Infratentorial Infarcts
Authors: Malm J. , Kristensen B. , Carlberg B. , Fagerlund M. , Olsson T.
Published: April 2003

Background and Purpose: Many comprehensive descriptions of the clinical spectrum of infratentorial infarcts in elderly patients and with a retrospective design have been published. The aim of this study was to describe the clinical characteristics and prognosis in young patients with isolated infratentorial infarcts. Methods: In a prospective series of 105 patients aged 18–44 years with cerebral infarction 24 had a brainstem or cerebellar infarction. The patient selection was validated in a population-based epidemiological survey. The patients were assessed acutely and at 4 and 12 months after onset. Extensive evaluation included CT and MRI scans, angiography, ultrasonic duplex scanning, transesophageal echocardiography and a chemistry panel including hematologic testing. The modified Rankin scale and NIH stroke scale were used for assessment of disability and neurological dysfunction. Results: Eighteen patients had a cerebellar infarct (posterior inferior cerebellar artery territory in 9 patients, superior cerebellar artery in 6, anterior inferior cerebellar artery in 2, nonterritorial in 1). Two patients had lateral medullary infarcts and 2 isolated pontine infarcts. In 2 patients MRI was normal despite repeated investigations. Hearing loss and tinnitus were the only explicit symptoms for superior cerebellar artery infarcts, but it was otherwise impossible to classify each case to a vascular territory according to clinical characteristics. The age-specific incidence of isolated cerebellar infarction was 1.8/100,000/year. The presumed causes were arterial dissection in 8 patients, idiopathic in 7, cardioembolic in 5, oral contraceptive use in 3 and protein S deficiency in 1 patient. One patient died during the acute phase and another developed a locked-in syndrome. At follow-up, 1 patient had a transitory ischemic attack and 1 a silent cerebral infarction. Twenty-two patients had a favorable outcome according to the modified Rankin scale (grade 0–2) and the NIH scale. Conclusions: Cerebellar infarctions are frequent among young stroke patients in northern Sweden. Arterial dissection is the prevailing stroke mechanism in infratentorial infarcts. The prognosis is favorable regarding motor impairment but cognitive deficits may prevent return to work.
Noninvasive Assessment of the Circle of Willis in Cerebral Ischemia: The Potential of CT Angiography and Contrast-Enhanced Transcranial Color-Coded Duplexsonography
Authors: Gahn G. , Gerber J. , Hallmeyer S. , Reichmann H. , von Kummer R.
Published: April 2003

Thirty-four patients with acute hemispheric ischemic strokes underwent both CT angiography and contrast-enhanced transcranial color-coded duplexsonography (TCCD) to study the effectiveness of the combined noninvasive techniques for evaluation of the circle of Willis. In 3/34 patients, CT angiography and contrast-enhanced TCCD demonstrated middle cerebral artery (MCA) occlusion, in 5 others MCA stenosis. A severe posterior cerebral artery stenosis was missed by CT angiography. In 8 patients, contrast-enhanced TCCD failed because of poor bone windows. In these patients, CT angiography was normal. CT angiography and contrast-enhanced TCCD are complementary noninvasive diagnostic tools. Disagreements between the diagnostic findings of these methods still need further evaluation by digital subtraction angiography.
Cerebral Thrombophlebitis in Three Patients with Probable Multiple Sclerosis
Authors: Albucher J.F. , Vuillemin-Azaïs C. , Manelfe C. , Clanet M. , Guiraud-Chaumeil B. , Chollet F.
Published: April 2003

We report 3 cases of young patients, 2 women and 1 man, who presented a cerebral venous thrombosis following intravenous treatment with high doses of corticosteroids. All of them presented a probable multiple sclerosis according to clinical, biological (CSF) and MRI criteria and were treated for the first time by a bolus of 1,000 mg of methylprednisolone OD during 5 days. All the usual causes of cerebral venous thrombosis were systematically excluded in all of them. The role of corticosteroid treatment in cerebral thrombophlebitis is discussed. All of them underwent a lumbar puncture a few days before corticosteroid treatment and the relationship between lumbar puncture and cerebral thrombophlebitis is also discussed. Cerebral venous thrombosis associated with corticosteroid treatment has rarely been reported. The relationship between corticosteroids and venous thrombosis has already been suggested but has never been clearly understood.
Bihemispheric Contribution to Motor Recovery after Stroke: A Longitudinal Study with Transcranial Doppler Ultrasonography
Authors: Cuadrado María Luz , Egido José Antonio , González-Gutiérrez José Luis , Varela-de-Seijas Eduardo
Published: April 2003

Background: Both cerebral hemispheres seem to contribute to motor recovery after stroke. We studied the effect of motor activity on cerebral blood flow in both hemispheres at different stages of stroke evolution. Methods: Thirty patients with hemiplegic stroke and 30 controls were included. Patients were examined within the first week (T1), 1 month (T2) and 6 months after stroke (T3). All subjects performed a 2-min sequential thumb-to-finger opposition task while blood flow velocities in both middle cerebral arteries were measured with transcranial Doppler ultrasonography (TCD). Results: Contralateral movement caused a higher increase in blood flow velocity than ipsilateral movement in controls (p < 0.0001). On the healthy side, patients showed a striking increase with ipsilateral movement (affected hand), which was similar to the increase with contralateral movement (normal hand) at all stages. On the damaged side, the increase with contralateral movement (affected hand) was low and was similar to the increase with ipsilateral movement (normal hand) at T1 and T2; however, at T3 the increase with contralateral movement was higher and the pattern of response was similar to that found in controls. Conclusions: TCD can trace the evolution of brain motor output following stroke. Compensatory activation of the healthy side of the brain may be already present soon after stroke, whereas function of the damaged side may improve during several months.
Alien Hand Sign after a Right Parietal Infarction
Authors: Martí-Fàbregas J. , Kulisevsky J. , Baró E. , Mendoza G. , Valencia C. , Martí-Vilalta J.-L.
Published: April 2003

Involuntary movements are unusual during or after acute stroke, and alien hand sign has not been reported after single parietal infarction. We report on a woman who presented with involuntary movements and a sense of alienness of her left upper limb following a right parietal infarction. This combination, that can meet the criteria for the ‘alien hand syndrome’, is rarely seen after acute lesions sparing the corpus callosum and the mesial frontal areas.
Endoluminal Stenting for Subclavian Artery Stenosis in Takayasu’s Arteritis
Authors: Lušić Ivo , Mašković Josip , Janković Stipan , Cambj-Sapunar Liana , Hozo Izet
Published: April 2003

We describe a patient with Takayasu’s arteritis (type I): occlusion of all large vessels of the aortic arch except the left subclavian artery which was, however, almost completely occluded, resulting in a characteristic subclavian steal syndrome. Elective left main subclavian artery balloon angioplasty followed by endoluminal stenting was performed with excellent results. After prolonged immunosuppressive treatment, at the 12-month follow-up there was no evidence of restenosis. In selected patients with Takayasu’s arteritis and subclavian stenosis, elective endoluminal stenting can be used as a definitive procedure or as a bridge to surgical revascularization.
Distribution, Severity and Risk Factors for Aortic Atherosclerosis in Cerebral Ischemia
Authors: Sen Souvik , Wu Katherine , McNamara Robert , Lima Joao , Piantadosi Steven , Oppenheimer Stephen M.
Published: April 2003

Significant thoracic aortic plaques (>4 mm) are an independent risk factor for ischemic stroke. Within 1 week of stroke/transient ischemic attack (TIA) onset, 105 consecutive patients underwent transesophageal echocardiography assessment of aortic plaque thickness using the criteria of Amarenco et al. (N Engl J Med 1994;331:1474–1479). A proximo-distal gradient was found in the distribution of aortic atheroma >4 mm (p = 0.04). Symptomatic coronary artery disease was associated with plaque in the proximal aorta (p = 0.03); extracranial carotid stenosis >70% was associated with plaque in the arch and descending aorta (p < 0.01). The severity of aortic plaque was associated with age on multivariable analysis (p = 0.0003 to p < 0.01). Only smoking showed predictive regional specificity (p = 0.03);no other risk factors were associated with aortic atheroma in any segment. In stroke/TIA patients, carotid stenosis >70% predicts aortic arch atheroma plaques >4 mm which may predispose to reinfarction after endarterectomy. Atheroma of the ascending aorta is associated with ischemic heart disease, and cardiac screening should be considered in asymptomatic patients.
Recent Infection as a Risk Factor for Intracerebral and Subarachnoid Hemorrhages
Authors: Kunze Alexandra K. , Annecke Andrea , Wigger Frank , Lichy Christoph , Buggle Florian , Schnippering Holger , Schnitzler Paul , Grau Armin J.
Published: April 2003

Previous infection has been shown to be a risk factor for acute cerebral ischemia. We tested the hypothesis that recent infection is also a risk factor for intracerebral hemorrhage (ICH) and subarachnoid hemorrhage (SAH). We performed a case-control study with 56 consecutive patients with ICH, 44 consecutive patients with SAH, and 56 and 44 neurological control patients, respectively. Infection within 4 weeks was associated with SAH independently of hypertension and smoking (p = 0.049). There was no significant association between infection and ICH. Recent infection, primarily upper respiratory tract infection, may be a risk factor for SAH by contributing to the formation and rupture of aneurysms.
Swallowing Disorders following Acute Stroke: Prevalence and Diagnostic Accuracy
Authors: Mann Giselle , Hankey Graeme J. , Cameron David
Published: April 2003

We prospectively examined 128 patients with acute first-ever stroke to determine the prevalence of swallowing disorders, the diagnostic accuracy of our clinical assessment of swallowing function compared with videofluoroscopy, and interobserver agreement for the clinical and videofluoroscopic diagnosis of swallowing disorders and aspiration. We found clinical and videofluoroscopic evidence of a swallowing disorder in 51% [95% confidence interval (CI) 42–60%] and 64% (95% CI 55–72%) of patients, respectively, and aspiration in 49% (95% CI 40–58%) and 22% (95% CI 15–29%) of patients, respectively. The optimal clinical criteria for detecting videofluoroscopic evidence of a swallowing disorder and aspiration were any clinical evidence of a swallowing disorder (sensitivity 73%, 95% CI 62–82%; specificity 89%, 95% CI 76–96%), and any clinical evidence of aspiration (sensitivity 93%, 95% CI 76–99%; specificity 63%, 95% CI 53–72%). The interobserver agreement between two speech pathologists for the clinical diagnosis of a swallowing disorder (κ: 0.82 ± 0.09) and aspiration (κ: 0.75 ± 0.09) was good, and between a speech pathologist and radiologist for the videofluoroscopic diagnosis of a swallowing disorder (κ: 0.75 ± 0.09) and aspiration (κ: 0.41 ± 0.09), it was good and fair, respectively. Although clinical bedside examination underestimates the frequency of swallowing abnormalities and overestimates the frequency of aspiration compared with videofluoroscopy, it may still offer valuable information for the diagnosis of swallowing impairment. Long-term follow-up studies are required to determine the independent functional significance of the findings of the bedside and videofluoroscopic examinations in predicting the occurrence of important outcome events such as aspiration pneumonia.
Diazepam Treatment to Increase the Cerebral GABAergic Activity in Acute Stroke: A Feasibility Study in 104 Patients
Authors: Lodder J. , Luijckx G.J. , van Raak L. , Kessels F.
Published: April 2003

In preparation of a trial on the neuroprotective effect of GABAergic activation by a benzodiazepine, we performed a feasibility study in 104 patients with acute (less than 24 h) stroke. 5 mg diazepam twice daily for 5 days (n = 44) was well tolerated, feasible, and appeared to be safe. Testing a dose of 10 mg twice daily for 5 days (n = 17) was stopped early because of drowsiness around day 5, interfering with regular patient care. A dose of 10 mg twice daily for 3 days was well tolerated, despite reported drowsiness in 12 of 43 patients. First-dose application by rectiole was feasible in 97% of the 104 patients. No blood pressure drop or respiratory arrest or insufficiency were detected, whereas the 2-week case fatality rate was similar to that of controls matched for age, sex, and stroke severity. We conclude that testing the GABAergic activity during the acute phase of stroke by 10 mg diazepam twice daily for 3 days is well tolerated and practically feasible, and it does not subject patients to an increased risk of potential serious adverse effects. Preparations for a large randomized trial are in a final stage.
Preconceptional Screening of Couples for Carriers of Cystic Fibrosis: A Prospective Evaluation of Effects, Costs and Savings for Different Mutation Detection Methods
Authors: Verheij Joke B.G.M. , Wildhagen Mark F. , Hofstra R.M.W. , Pals G. , Habbema J. Dik F. , ten Kate Leo P.
Published: April 2003

Objective: The aim of this study was to perform a prospective evaluation of the effects, costs and savings of a preconceptional screening programme of couples for carriers of cystic fibrosis (CF). Methods: A decision model for both single-entry two-step (SETS) and double-entry two-step (DETS) couple screening was constructed. Two mutation detection methods were considered: allele-specific oligonucleotide (ASO) hybridisation screening of 32 mutations, with a sensitivity of 90%, and denaturing gradient gel electrophoresis (DGGE), with a sensitivity of 98%. In our model, the following combinations were used: (1) ASO for both steps; (2) DGGE for both steps, and (3) ASO for the first step and DGGE for the second step. The model is demonstrated using figures from the Netherlands, where there is a carrier frequency of 1:30. We estimated the value of different choices and probabilities in a decision tree and determined the costs of screening for CF and the costs of the illness itself. Results: We found that with most of the combinations of mutation detection methods, SETS couple screening could offer positive net savings in the Netherlands. The ASO/DGGE combination resulted in the highest net savings. DETS couple screening for all combinations, including testing with DGGE in both steps, did not show a positive cost-savings balance at all, not even with an uptake rate of 100%. The maximum number of carrier couples identified when screening 100,000 couples with the ASO/DGGE combination was 98 (SETS). This could result in about 25 fewer children born with CF each year in the Netherlands, under the following assumptions: (1) each couple has two children and 10% of couples are unable to have children; (2) of detected carrier couples, 15% decide not to have children and 85% make use of prenatal diagnosis; (3) of those fetuses diagnosed with CF, 80% are aborted, and (4) prenatal diagnosis carries a 0.75% risk of iatrogenic abortion. Conclusions: The results of this evaluation show that there are no financial objections to the preconceptional screening of couples in the Netherlands when the above-mentioned assumptions apply; thus, further evaluation can concentrate on the balance of the non-economic consequences of screening for participants and for society.
Glycogen Storage Disease Type II: Birth Prevalence Agrees with Predicted Genotype Frequency
Authors: Ausems M.G.E.M. , ten Berg K. , Kroos M.A. , van Diggelen O.P. , Wevers R.A. , Poorthuis B.J.H.M. , Niezen-Koning K.E. , van der Ploeg A.T. , Beemer F.A. , Reuser A.J.J. , Sandkuijl L.A. , Wokke J.H.J.
Published: April 2003

Objectives: To compare the overall birth prevalence of diagnosed glycogen storage disease type II (GSD II) with the predicted frequency based on mutation screening, in order to determine whether GSD II is an underdiagnosed condition, and to analyze which medical disciplines recognize GSD II. Methods: Retrospective data on all enzymatic diagnoses of GSD II were collected from diagnostic labs throughout the Netherlands, covering the period from January 1, 1972 to December 31, 1996. Age-specific diagnostic incidence rates were calculated for the entire study period. By adding together the diagnostic incidences for all age groups, we calculated the birth prevalence of diagnosed GSD II and compared these figures with the predicted frequency based on mutation screening in a random sample from the general population. The medical specialization of the referring clinicians was also recorded. Results: GSD II was diagnosed in 154 individuals, including 11 prenatal diagnoses. The birth prevalences of the various phenotypes were 1/101,000 (infantile form), 1/720,000 (juvenile form) and 1/53,000 (adult form). The birth prevalence of the adult and infantile phenotype together was 1/35,000. Eighty-two percent of the patients were diagnosed in university hospitals. Of the patients with infantile GSD II, 71% were diagnosed by a pediatrician, whereas most patients with adult GSD II were diagnosed by a neurologist (80%). Conclusions: There is no evidence for the underdiagnosis of GSD II in the Netherlands, as the calculated birth prevalences of the disease are consistent with previous predictions based on mutation screening in a random sample of newborns. The worldwide birth prevalence of the disease may well be higher than 1 in 100,000. GSD II is mainly diagnosed in university hospitals.
Inhibition of Dentin Demineralization by Fluoride in vitro
Authors: ten Cate J.  M. , Damen J.J.M. , Buijs M.J.
Published: April 2003

Compared with the knowledge accumulated on enamel-fluoride interactions, relatively little data is available regarding fluoride effects on dentin. This applies to both laboratory and clinical studies into the efficacy of fluoride schemes for the prevention of root surface caries. This study aimed to determine the effects of fluoride and pH on the demineralization of dentin, such as to provide information necessary to develop preventive programmes. Bovine dentin blocks were subjected to undersaturated calcium- and phosphate-containing solutions in the pH range 4.0–6.0 with fluoride added at concentrations between 0.5 and 10 ppm. Non-fluoride solutions served as controls. Mineral loss was assessed chemically and by transversal microradiography. Comparisons were made with similar studies on enamel demineralization. The results showed that demineralization of dentin depends on both pH and fluoride concentration in the demineralizing solution. Inhibition of demineralization that could be relevant from a clinical point of view was found at fluoride values 5–10 times the corresponding values for enamel. Also rapid depletion of fluoride from the solutions was observed, indicating the high uptake capacity of dentin for fluoride. Lesion depth depended on pH of the solution while the fluoride levels were associated with the surface layer, both in mineral content and depth. For dentin we propose a demineralization mechanism where acid penetrates rapidly into the tissue, presumably through the tubules, after which the released calcium and phosphate is partly trapped by the inward diffusing fluoride. This leads to the formation of a surface layer, which may even be hypermineralized compared to sound dentin.
Five-Year Incidence of Caries, Salivary and Microbial Conditions in 60-, 70- and 80-Year-Old Swedish Individuals
Authors: Fure S.
Published: April 2003

The 5-year incidence of dental caries in a random sample of 60-, 70- and 80-year-old inhabitants of Göteborg was related to salivary and microbial conditions. Of the 208 persons examined at baseline, 148 (71%) participated in the follow-up examination; 69, 51 and 28, respectively, in the different age groups. The study revealed that 27% of the participants had not developed any carious lesions during the 5-year period and that the incidence of coronal and root caries increased with age. In the 60-year-olds, 2.5% of the susceptible coronal and root surfaces, respectively, had decayed, while the corresponding figures for the 80-year-olds were 8.8% for coronal surfaces and 9.8% for root surfaces. In all, 18% had an unstimulated saliva secretion rate of below 0.1 ml/min and 14% had a stimulated secretion rate of < 0.7 ml/min, with a mean rate which decreased with increasing age from 2.0 to 1.6 and 1.3 ml/min (p = 0.02). The overall salivary counts of lactobacilli and mutans streptococci, particularly the subspecies of Streptococcus sobrinus, had increased during the period. In the respective age groups of 60, 70 and 80 years, 15, 39 and 39% had a mutans streptococci count of ≥ 106 CFU/ml in saliva and the corresponding figures for ≥ 105 lactobacilli counts were 22, 31 and 43%. In the stepwise regression analysis, it was found that age, salivary levels of mutans streptococci and lactobacilli and number of teeth were the best predictors of the incidence of root caries. In conclusion, these observations indicate that there is an increased risk of dental caries with age owing to unfavourable microbial and salivary conditions.
Inhibition of Salivary Amylase by Black and Green Teas and Their Effects on the Intraoral Hydrolysis of Starch
Authors: Zhang J. , Kashket S.
Published: April 2003

Tea decoctions prepared from a number of black and green teas inhibited amylase in human saliva. Black teas gave higher levels of inhibition than green teas, and removal of tea tannins with gelatin led to the loss of inhibitory activity from all decoctions. Streptococcal amylase was similarly inhibited by tea decoctions. Fluoride was without effect on amylase. Since salivary amylase hydrolyzes food starch to low molecular weight fermentable carbohydrates, experiments were carried out to determine whether tea decoctions would interfere with the release of maltose in food particles that became entrapped on the dentition. Subjects consumed salted crackers and rinsed subsequently for 30 s with black or green tea decoctions, or water. Maltose release was reduced by up to about 70% after rinsing with the teas. Black tea decoction was significantly more effective than green tea, in agreement with the in vitro data. The observations supported the hypothesis that tea consumption can be effective in reducing the cariogenic potential of starch-containing foods such as crackers and cakes. Tea may reduce the tendency for these foods to serve as slow-release sources of fermentable carbohydrate.
Composition of Pellicles Formed in vivo on Tooth Surfaces in Different Parts of the Dentition, and in vitro on Hydroxyapatite
Authors: Carlén A. , Börjesson A.-C. , Nikdel K. , Olsson J.
Published: April 2003

Saliva from the major salivary glands dominates different areas of the mouth. The parotid (PS) and submandibular/sublingual (SMS) saliva differ in their protein composition, and thus, the composition of pellicles formed in various parts of the dentition might vary. In this study, proteins incorporated in 60–min pellicles from the premolar and front regions of the mouths of 4 subjects were examined using sodium dodecyl sulphate–polyacrylamide gel electrophoresis and immunoblotting using antibodies to amylase, albumin, IgA, parotid saliva agglutinin, low molecular weight SMS mucin (MG2) and proline–rich proteins. Pellicles formed in vitro on hydroxyapatite using PS, SMS and whole saliva from the subjects were examined in a similar manner. The pellicles formed in vitro and in vivo showed a major difference in the appearance of albumin. Bands of albumin were clearly stained in the samples of in vivo pellicles but were not observed or hardly visible in Western blots from the experimental, in vitro pellicles. The sites in the dentition from which a specific protein was recovered could differ between the 4 individuals. The overall protein pattern of the pellicles showed, however, characteristics typical of the saliva which may prevail in the part of the mouth where the pellicles were formed. Thus, parotid saliva agglutinin, a receptor for Streptococcus mutans, was primarily found in the premolar part of the dentition. The mucin MG2, which may mediate the adherence of Streptococcus sanguis and Streptococcus oralis, was in no case clearly seen in pellicles from the premolar region of the upper jaw. The observed variations might be important to the establishment of microflora and tooth–related disease patterns in various parts of the dentition.
Effects of Mouth Rinses with Xylitol and Fluoride on Dental Plaque and Saliva
Authors: Giertsen E. , Emberland H. , Scheie A. Aa.
Published: April 2003

The aim of this study was to test the hypothesis that xylitol, alone and in combination with fluoride, affects the salivary flow rate and micro–biota, dental plaque accumulation, gingivitis development, and the acidogenic potential of plaque. Three groups, each of 10 subjects, rinsed for 1 min 3 times daily over two 4–week periods, first with 10 ml water (control), and thereafter with either 0.05% NaF, 40% xylitol, or with 0.025% NaF plus 20% xylitol according to a double–blind controlled design. They performed habitual mechanical tooth cleaning during the first 2 weeks of each period but abstained from interdental cleaning during the final 2 weeks. While mouth rinsing was continued, all mechanical oral hygiene was discontinued the last 2 days of each period to permit plaque accumulation. The last mouth rinse was administered in the clinic before the final examination. The following parameters were assessed: (1) unstimulated and paraffin–stimulated salivary secretion rates; (2) salivary micro–biota; (3) plaque index; (4) papillar bleeding; (5) plaque pH response to sucrose, and (6) lactate formation by dental plaque. No statistically significant differences in any of the parameters were found. In conclusion, three daily mouth rinses with fluoride and xylitol, separately or in combination, did not affect the salivary flow rate or micro–biota, dental plaque accumulation, gingivitis development, or the acidogenic potential of plaque.