The Effect of Nimodipine, a Centrally Active Calcium Antagonist, on Visual Function and Macular Blood Flow in Patients with Normal-Tension Glaucoma and Control Subjects

Objective The objective of this study was to compare the interictal cortical response to a visual stimulus between migraine with aura (MWA), migraine without aura (MwoA), and control subjects. Methods In a prospective case-control study, blood oxygen level-dependent functional magnetic resonance imaging (BOLD fMRI) was used to assess the response to a visual stimulus and arterial spin labeled perfusion MR to determine resting cerebral blood flow. A standardized questionnaire was used to assess interictal visual discomfort. Results Seventy-five subjects (25 MWA, 25 MwoA, and 25 controls) were studied. BOLD fMRI response to visual stimulation within primary visual cortex was greater in MWA (3.09 ± 0.15%) compared to MwoA (2.36 ± 0.13%, p = 0.0008) and control subjects (2.47 ± 0.11%, p = 0.002); responses were also greater in the lateral geniculate nuclei in MWA. No difference was found between MwoA and control groups. Whole brain analysis showed that increased activation in MWA was confined to the occipital pole. Regional resting cerebral blood flow did not differ between groups. MWA and MwoA subjects had significantly greater levels of interictal visual discomfort compared to controls ( p = 0.008 and p = 0.005, respectively), but this did not correlate with BOLD response. Conclusions Despite similar interictal symptoms of visual discomfort, only MWA subjects have cortical hyperresponsiveness to visual stimulus, suggesting a direct connection between cortical hyperresponsiveness and aura itself.

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Early Evidence of Sepsis-Associated Hyperperfusion—A Study of Cerebral Blood Flow Measured With MRI Arterial Spin Labeling in Critically Ill Septic Patients and Control Subjects*

Critical Care Medicine ◽

10.1097/ccm.0000000000003147 ◽

2018 ◽

Vol 46 (7) ◽

pp. e663-e669 ◽

Cited By ~ 5

Author(s):

Marie-Hélène Masse ◽

Marie Anne Richard ◽

Frédérick D’Aragon ◽

Charles St-Arnaud ◽

Michael Mayette ◽

...

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Critically Ill ◽

Arterial Spin Labeling ◽

Spin Labeling ◽

Control Subjects ◽

Early Evidence ◽

And Control

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Impaired Nutritive Skeletal Muscle Blood Flow in Patients with Chronic Renal Failure

Clinical Science ◽

10.1042/cs0790239 ◽

1990 ◽

Vol 79 (3) ◽

pp. 239-245 ◽

Cited By ~ 24

Author(s):

John R. Bradley ◽

Janice R. Anderson ◽

David B. Evans ◽

Alan J. Cowley

Keyword(s):

Skeletal Muscle ◽

Renal Failure ◽

Blood Flow ◽

Chronic Renal Failure ◽

Muscle Blood Flow ◽

Skeletal Muscle Blood Flow ◽

Control Subjects ◽

Calf Blood Flow ◽

Before And After ◽

And Control

1. The possibility that abnormalities of skeletal muscle may limit the exercise tolerance of patients with chronic renal failure was investigated in patients undergoing regular haemodialysis. 2. Blood flow to the calf, a vascular bed consisting predominantly of skeletal muscle, was measured in six patients before and after exercise and compared with values obtained from 12 control subjects. 3. The patients were limited on exertion and had an abnormal response of calf blood flow to bicycle exercise. Resting calf blood flow was similar in patients and control subjects, but the mean increase in calf blood flow in response to submaximal exercise was 0.55 (sem 0.12) ml min−-1 100 ml−-1 in the patients and 1.43 (sem 0.17) ml min−-1 100 ml−-1 in the control subjects. The increase after symptom-limited maximal exercise was 1.50 (sem 0.80) ml min−-1 100 ml−-1 in the patients and 4.20 (sem 0.40) ml min−-1 100 ml−-1 in the control subjects. 4. Skeletal muscle biopsies from eight haemodialysis patients were studied by histochemistry and electron microscopy. 5. Oxidative enzyme activity was increased and there were large subsarcolemmal aggregates of structurally normal mitochondria. Necrotic capillaries were observed as empty basement membrane tubes containing fragments of degenerating endothelium. 6. The changes were compatible with a response to a chronic reduction in skeletal muscle blood flow.

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Determinants of kinetic energy of blood flow in the four-chambered heart in athletes and sedentary controls

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00544.2015 ◽

2016 ◽

Vol 310 (1) ◽

pp. H113-H122 ◽

Cited By ~ 21

Author(s):

K. Steding-Ehrenborg ◽

P. M. Arvidsson ◽

J. Töger ◽

M. Rydberg ◽

E. Heiberg ◽

...

Keyword(s):

Blood Flow ◽

Kinetic Energy ◽

Energy Expenditure ◽

Cardiac Index ◽

Left Ventricular ◽

Control Subjects ◽

End Diastolic Volume ◽

Lv Mass ◽

The Mean ◽

And Control

The kinetic energy (KE) of intracardiac blood may play an important role in cardiac function. The aims of the present study were to 1) quantify and investigate the determinants of KE, 2) compare the KE expenditure of intracardiac blood between athletes and control subjects, and 3) quantify the amount of KE inside and outside the diastolic vortex. Fourteen athletes and fourteen volunteers underwent cardiac MRI, including four-dimensional phase-contrast sequences. KE was quantified in four chambers, and energy expenditure was calculated by determining the mean KE/cardiac index. Left ventricular (LV) mass was an independent predictor of diastolic LVKE ( R2= 0.66, P < 0.001), whereas right ventricular (RV) end-diastolic volume was important for diastolic RVKE ( R2= 0.76, P < 0.001). The mean KE/cardiac index did not differ between groups (control subjects: 0.53 ± 0.14 mJ·l−1·min·m2and athletes: 0.56 ± 0.21 mJ·l−1·min·m2, P = 0.98). Mean LV diastolic vortex KE made up 70 ± 1% and 73 ± 2% of total LV diastolic KE in athletes and control subjects ( P = 0.18). In conclusion, the characteristics of the LV as a pressure pump and the RV as a volume pump are demonstrated as an association between LVKE and LV mass and between RVKE and end-diastolic volume. This also suggests different filling mechanisms where the LV is dependent on diastolic suction, whereas the RV fills with a basal movement of the atrioventricular plane over “stationary” blood. Both groups had similar energy expenditure for intracardiac blood flow, indicating similar pumping efficiency, likely explained by the lower heart rate that cancels the higher KE per heart beat in athletes. The majority of LVKE is found within the LV diastolic vortex, in contrast to earlier findings.

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Pilot Study on Visual Function and Fundus Autofluorescence Assessment in Diabetic Patients

Journal of Ophthalmology ◽

10.1155/2016/1287847 ◽

2016 ◽

Vol 2016 ◽

pp. 1-10 ◽

Cited By ~ 2

Author(s):

Ana M. Calvo-Maroto ◽

José J. Esteve-Taboada ◽

Rafael J. Pérez-Cambrodí ◽

David Madrid-Costa ◽

Alejandro Cerviño

Keyword(s):

Visual Function ◽

Pigment Epithelium ◽

Fundus Autofluorescence ◽

Retinal Pigment ◽

Self Management ◽

Diabetic Patients ◽

Control Subjects ◽

Fundus Imaging ◽

And Control

Purpose. Evaluate optimized fundus autofluorescence (FAF) imaging in early stages of diabetic retinopathy (DR) and relate findings with conventional colour fundus imaging and visual function in diabetic patients and control subjects.Materials and Methods. FAF and colour images were obtained using the CR-2 Plus digital nonmydriatic retinal camera in seven diabetic patients and thirteen control subjects. Visual-Functioning Questionnaire-25 (VFQ-25) and Diabetes Self-Management Questionnaire (DSMQ) were used to assess the quality of life and diabetes self-care. Contrast sensitivity function (CSF) was evaluated with the Vistech 6500 chart.Results. FAF and optimized-FAF imaging showed more retinal alterations related to DR than colour imaging. In diabetic patients, compatible signs with microaneurysms, capillary dilations, and haemorrhages were less numerous in colour imaging than optimized-FAF and FAF imaging in areas analysed. Control subjects at risk of developing DM showed more retinal pigment epithelium defects than those without risk in all retinal areas. Significant differences were not found in VFQ-25 and CSF between diabetic patients and control subjects.Conclusions. FAF and optimized-FAF imaging showed significant alterations related to DR not observed in colour imaging. FAF and optimized-FAF images could be a useful complementary tool for detecting early alterations associated with the development and progression of DR.

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Coding Region Mutation Screening in Optineurin in Chinese Normal-Tension Glaucoma Patients

Disease Markers ◽

10.1155/2019/5820537 ◽

2019 ◽

Vol 2019 ◽

pp. 1-5 ◽

Cited By ~ 1

Author(s):

Jing Na He ◽

Shiyao Lu ◽

Li Jia Chen ◽

Pancy Oi Sin Tam ◽

Bi Ning Zhang ◽

...

Keyword(s):

Mutation Screening ◽

Susceptibility Gene ◽

Normal Tension Glaucoma ◽

Chinese Patients ◽

Causative Mutation ◽

Allelic Association ◽

Coding Region ◽

Control Subjects ◽

Genotypic Association ◽

And Control

Purpose. To study the roles of sequence alterations in the optineurin (OPTN) gene-coding region in normal-tension glaucoma (NTG) among Chinese patients. Methods. Genomic DNA was extracted from 190 NTG patients and 201 control subjects. The thirteen exons of OPTN were amplified by polymerase chain reaction and analyzed by direct sequencing. Detected sequence changes were compared between NTG patients and control subjects. Results. Seven sequence changes in OPTN were identified in both NTG patients and control subjects. Among them, c.464G>A (T34 T), c.509C>T (T49T), c.806G>A (V148V), and c.959T>C (P199P) were synonymous codon changes, whilst c.655T>A (M98K), c.1996G>A (R545Q), and c.1582T>C (I407T) were missense changes. Two previously reported heterozygous mutations, c.458G>A (E50K) in exon 4 and c.691_692insAG in exon 6, were not found in this study. Out of these seven OPTN sequence variants, c.464G>A (T34T) was significantly associated with NTG in both the allelic and genotypic association analyses (allelic association: p=0.0001, OR=2.20, 95% CI: 1.46-3.31; genotypic association: p=0.0001), whereas the association of other variants with NTG did not reach statistical significance (p>0.05). Variants c.1582 T>C (I407T) and c.806G>A (V148V) were identified in one and two NTG patients, respectively, but not in the control subjects. Conclusions. This study confirmed the association of the OPTN T34T variant with NTG, suggesting that OPTN is a susceptibility gene for NTG in Chinese. Moreover, a variant with amino acid change (I407T) was identified in NTG but not in controls. Further studies are warranted to assess whether this variant is a causative mutation for NTG.

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Cerebral blood flow increases during insulin-induced hypoglycaemia in Type 1 (insulin-dependent) diabetic patients and control subjects

Diabetologia ◽

10.1007/bf00299022 ◽

1987 ◽

Vol 30 (5) ◽

pp. 305-309 ◽

Cited By ~ 43

Author(s):

H. A. W. Neil ◽

E. A. M. Gale ◽

S. J. C. Hamilton ◽

I. Lopez-Espinoza ◽

R. Kaura ◽

...

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Diabetic Patients ◽

Control Subjects ◽

Insulin Dependent ◽

Insulin Dependent Diabetic ◽

And Control

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Forearm vasoconstriction to endothelin-1 is impaired, but constriction to sarafotoxin 6c and vasodilatation to BQ-123 unaltered, in patients with essential hypertension

Clinical Science ◽

10.1042/cs103s053s ◽

2002 ◽

Vol 103 (s2002) ◽

pp. 53S-58S ◽

Cited By ~ 8

Author(s):

Charles J. FERRO ◽

William G. HAYNES ◽

Malcolm F. HAND ◽

David J. WEBB

Keyword(s):

Blood Pressure ◽

Blood Flow ◽

Essential Hypertension ◽

Receptor Agonist ◽

Forearm Blood Flow ◽

Hypertensive Patients ◽

Control Subjects ◽

Eta Receptor ◽

Etb Receptor ◽

And Control

The importance of endothelin-1 (ET-1) in the pathophysiology of essential hypertension is unclear. We therefore compared the effects of endothelin ETA receptor blockade and the stimulation of ETA and ETB receptors, and their interaction with the sympathetic nervous system, in the forearm resistance vessels of patients with essential hypertension and healthy control subjects. A total of 27 untreated patients with essential hypertension (blood pressure >160/100mmHg) and 25 normotensive (blood pressure <140/90mmHg) age- and sex-matched control subjects participated in these studies. A total of 10 patients and 10 controls took part in each phase. Locally active doses of study drugs were infused into the non-dominant brachial artery, while forearm blood flow was measured by venous occlusion plethysmography. A 60min infusion of BQ-123 (an ETA receptor antagonist; 100nmol/min) significantly increased forearm blood flow by 40±8% in hypertensive patients and by 35±5% in controls, with no difference between groups (P = 0.49). Forearm vasoconstriction to ET-1 (an ETA and ETB receptor agonist; 5 pmol/min) for 90min was significantly blunted in hypertensive patients (21±4%) compared with control subjects (37±3%; P = 0.0001). Forearm vasoconstriction to sarafotoxin S6c (an ETB receptor agonist; 10 pmol/min) for 90min was similar in hypertensive patients (44±5%) and control subjects (48±4%; P = 0.95). Sympathetically mediated vasoconstriction produced by lower-body negative pressure was not different in hypertensive patients compared with controls, and was not affected by infusion of ET-1 or sarafotoxin S6c. There were no differences in the observed increase in forearm blood flow with a control vasodilator (sodium nitroprusside) or the observed decrease in forearm blood flow with a control vasoconstrictor (noradrenaline) between hypertensive patients and control subjects. BQ-123 produced a significant increase in forearm blood flow in hypertensive patients, consistent with the anti-hypertensive actions of this agent. In conclusion, forearm vasoconstriction to ET-1, but not to sarafotoxin S6c, was reduced in patients with essential hypertension, consistent with possible down-regulation of the ETA receptor in this condition.

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