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Focal electroretinograms and fundus appearance in nonexudative age-related macular degeneration 总被引:4,自引:0,他引:4
B. Falsini Sebastiano Serrao Antonello Fadda Giancarlo Iarossi Giovanni Porrello Francesco Cocco Erasmo Merendino 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1999,237(3):193-200
· Background: The aim of this study was to evaluate the focal electroretinogram (FERG), an objective indicator of outer
retinal function, in nonexudative age-related macular degeneration (NE-AMD), and to compare FERG results with morphological
lesions assessed by stereoscopic fundus photographs and fluorescein angiograms. · Methods: Twenty-five patients (25 eyes)
with bilateral NE-AMD (visual acuity of the study eyes ≥0.4) as well as 10 age- and sex-matched control subjects (10 eyes)
were evaluated. FERGs were recorded from the macular region (9°) in response to sinusoidal stimuli flickered at 32 Hz. Amplitude
and phase angle of the Fourier-analyzed FERG fundamental component were measured. Fundus lesions were graded from color slides
according to the Wisconsin age-related maculopathy grading system [15]. Fluorescein angiograms were evaluated by an image
analysis technique to compute the area with pathological hyperfluorescence (associated with drusen and/or retinal pigment
epithelial atrophy) within the macular (approximately 9°×9°) region. · Results: Compared to control eyes, NE-AMD eyes had
a reduction in the mean FERG amplitude (57% loss, P<0.001) with no phase changes. Amplitudes of individual affected eyes were negatively correlated with either the Wisconsin
grading score (r=–0.63, P<0.001) or the percentage area of pathological hyperfluorescence (r=–0.70, P<0.01). Eyes with minimal NE-AMD lesions (Wisconsin score ≤6) and normal acuity had a lower mean amplitude (47% loss, P<0.05) than that of control eyes. · Conclusions: The results indicate that, in NE-AMD, the FERG is altered in parallel with
the extent and severity of fundus lesions. However, a functional impairment of outer macular layers, which is detected by
FERG losses, could precede morphological changes typical of more advanced disease.
Received: 6 March 1998 Revised version received: 5 June 1998 Accepted: 17 June 1998 相似文献
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Armando Perrotta MD PhD Natalia Arce‐Leal MD PhD Cristina Tassorelli MD PhD Valeria Gasperi PhD Grazia Sances MD Fabio Blandini MD PhD Mariano Serrao MD PhD Monica Bolla MD Francesco Pierelli MD DrMSc Giuseppe Nappi MD DrMSc Mauro Maccarrone DrMSc Giorgio Sandrini MD DrMSc 《Headache》2012,52(9):1350-1361
Objectives.— We investigated (1) a possible relationship between the functional activity of the endocannabinoid system and the facilitation of pain processing in migraineurs with medication‐overuse headache, and (2) the effect of withdrawal treatment on both. Background.— The endocannabinoid system antinociception effect includes prevention of nociceptive pathways sensitization. The sensitization of the pain pathways has been demonstrated to be pivotal in the development and maintenance of chronic form of migraine, including medication‐overuse headache. Methods.— We used the temporal summation threshold of the nociceptive withdrawal reflex to explore the spinal cord pain processing, and the platelet activity of the enzyme fatty acid amide hydrolase to detect the functional state of the endocannabinoid system in 27 medication‐overuse headache subjects before and 10 and 60 days after a standard withdrawal treatment and compared results with those of 14 controls. Results.— A significantly reduced temporal summation threshold and increased related pain sensation was found in subjects before withdrawal treatment when compared with controls. A significant fatty acid amide hydrolase activity reduction coupled with a significant improvement (reduction) in facilitation of spinal cord pain processing (increase in temporal summation threshold and reduction in related pain sensation) was found in medication‐overuse headache subjects at both 10 and 60 days after withdrawal treatment when compared with medication‐overuse headache subjects before withdrawal treatment. Conclusions.— We demonstrated a marked facilitation in spinal cord pain processing in medication‐overuse headache before withdrawal treatment when compared with controls. Furthermore, the acute reduction of the fatty acid amide hydrolase activity coupled with a reduction of the facilitation in pain processing immediately (10 days) after withdrawal treatment and its persistence 60 days after withdrawal treatment could represent the consequence of a mechanism devoted to acutely reduce the degradation of endocannabinoids and aimed to increase the activity of the endocannabinoid system that results in an antinociceptive effect. 相似文献
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Yash Paul Sharma Krishna Santosh Vemuri Dinakar Bootla Kewal Kanabar C.R. Pruthvi Navjyot Kaur Krishna Prasad Nevali Prashant Panda G. Kasinadhuni Lipi Uppal Soumitra Mohanty 《Indian heart journal》2021,73(2):174-179
BackgroundCardiovascular disease is the leading cause of death in India. Our aim is to study the clinical, epidemiological profile and in-hospital outcomes of patients presenting with acute coronary syndrome.MethodsWe did a prospective single center observational study of the 1203 patients presenting with ACS to a tertiary referral center in North India over a period of one year (July 2018–June 2019).ResultsThe mean age of study population was 58.4 ± 12.5 years. STEMI and NSTE-ACS accounted for 69.9% and 31.1% respectively. 62.1% of our patients were from rural background. The median time to hospital admission was 600 min for STEMI patients, thrombolysis was performed in 52% of cases. Cardiogenic shock at presentation was noted in 18%. Coronary angiography and percutaneous coronary intervention were done in 1062 (88.3%) and 733 (60.9%) patients respectively. The overall in-hospital mortality was 7.6%. STEMI patients had higher mortality than NSTE-ACS (8.9% vs 4.5% p < 0.001). Female gender (OR?3.306 C.I. 1.87–5.845), severe MR (OR?4.65, C.I.?1.187–18.18), acute kidney injury (AKI) at admission (OR-5.15, C.I.?2.5–10.63), higher Killip class (class III/IV) (OR?3.378,C.I.?1.292–8.849), AF (OR?3.25, C.I.?1,18–8.92), complete heart block (CHB) (OR?4.44,C.I.?2.09–9.43) and right bundle branch block (RBBB) (OR?2.86, C.I.?1.2–6.8) were significant predictors of in hospital mortality.ConclusionsOur study represents the predominance of STEMI as the initial ACS presentation with a considerable delay in first medical contact and higher prevalence of cardiogenic shock (CS). STEMI patients had higher mortality. Female sex, severe MR, AKI, higher Killips class, AF, CHB, RBBB being predictors of high in-hospital mortality in ACS patients. 相似文献
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Gianluca Coppola Antonio Di Renzo Emanuele Tinelli Barbara Petolicchio Vincenzo Parisi Mariano Serrao Camillo Porcaro Marco Fiorelli Francesca Caramia Jean Schoenen Vittorio Di Piero Francesco Pierelli 《The journal of headache and pain》2021,22(1)
BackgroundWe searched for differences in resting-state functional connectivity (FC) between brain networks and its relationship with the microstructure of the thalamus between migraine with pure visual auras (MA), and migraine with complex neurological auras (MA+), i.e. with the addition of at least one of sensory or language symptom.Methods3T MRI data were obtained from 20 patients with MA and 15 with MA + and compared with those from 19 healthy controls (HCs). We collected resting state data among independent component networks. Diffusivity metrics of bilateral thalami were calculated and correlated with resting state ICs-Z-scores.ResultsAs compared to HCs, both patients with MA and MA + disclosed disrupted FC between the default mode network (DMN) and the right dorsal attention system (DAS). The MA + subgroup had lower microstructural metrics than both HCs and the MA subgroup, which correlated negatively with the strength of DMN connectivity. Although the microstructural metrics of MA patients did not differ from those of HCs, these patients lacked the correlation with the strength of DAS connectivity found in HCs.ConclusionsThe present findings suggest that, as far as MRI profiles are concerned, the two clinical phenotypes of migraine with aura have both common and distinct morpho-functional features of nodes in the thalamo-cortical network. 相似文献
8.
Mariano Serrao Carmela Conte Carlo Casali Alberto Ranavolo Silvia Mari Roberto Di Fabio Armando Perrotta Gianluca Coppola Luca Padua Stefano Monamì Giorgio Sandrini Francesco Pierelli 《Cerebellum (London, England)》2013,12(5):607-616
Stopping during walking, a dynamic motor task frequent in everyday life, is very challenging for ataxic patients, as it reduces their gait stability and increases the incidence of falls. This study was conducted to analyse the biomechanical characteristics of upper and lower body segments during abrupt stopping in ataxic patients in order to identify possible strategies used to counteract the instability in the sagittal and frontal plane. Twelve patients with primary degenerative cerebellar ataxia and 12 age- and sex-matched healthy subjects were studied. Time–distance parameters, dynamic stability of the centre of mass, upper body measures and lower joint kinematic and kinetic parameters were analysed. The results indicate that ataxic patients have a great difficulty in stopping abruptly during walking and adopt a multi-step stopping strategy, occasionally with feet parallel, to compensate for their inability to coordinate the upper body and to generate a well-coordinated lower limb joint flexor–extensor pattern and appropriate braking forces for progressively decelerating the progression of the body in the sagittal plane. A specific rehabilitation treatment designed to improve the ability of ataxic patients to transform unplanned stopping into planned stopping, to coordinate upper body and to execute an effective flexion–extension pattern of the hip and knee joints may be useful in these patients in order to improve their stopping performance and prevent falls. 相似文献
9.
The ankle joint of a powered ankle–foot orthosis (PAFO) is a prominent component, as it must withstand the dynamic loading conditions during its service time, while delivering all the functional requirements such as reducing the metabolic effort during walking, minimizing the stress on the user’s joint, and improving the gait stability of the impaired subjects. More often, the life of an AFO is limited by the performance of its joint; hence, a careful design consideration and material selection are required to increase the AFO’s service life. In the present work, a compact AFO joint was designed based on a worm gear mechanism with steel and brass counterparts due to the fact of its large torque transfer capability in a single stage, enabling a compact joint. Further, it provided an added advantage of self-locking due to the large friction that prevents backdrive, which is beneficial for drop-foot recovery. The design was verified using nonlinear finite element analysis for maximum torque situations at the ankle joint during normal walking. The results indicate stress levels within its design performance; however, it is recommended to select high-grade structural steel for the ankle shaft as the highest stresses in AFO were located on it. 相似文献