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Economic policymakers, national and supranational bodies have recognized small and medium-sized enterprises (SMEs) as the bearers of economic growth, but also the fact that access to funding sources is one of the main limiting factors for SMEs, and therefore a limiting factor for the economy. International financial institutions (MFIs) may play an important role in ensuring access to adequate sources of funds, especially in countries with a poorly developed financial system, which have undergone various transformational changes and where capital accumulation is low. The investment portfolio of MFIs may be diversified, but this paper analyzes only the institutions of the World Bank Group and particularly those projects that have been implemented in the last ten years, which directly or indirectly contribute to the development of entrepreneurship in Serbia. These institutions support entrepreneurship at macro level (direct support to the state through a variety of incentive programs, stabilization programs, improvement of the economic environment, support to the budget, etc.) and the micro level (loans, grants, equity investments, hybrid instruments, technical assistance and instruments to minimize the risk). In the last ten years, the analyzed institutions have invested around 3.7 billion dollars in stimulating entrepreneurship, only through analyzed projects, which represents around 5% of total bank landing to the economy sector.

Background: Smell loss is a common symptom of COVID-19 infection. Majority of the studies that evaluated olfactory impairment in COVID-19 used questionnaires (subjective smell evaluations) and did not compare the results with objective or semiobjective measures of smell. We performed smell testing in hospitalised and self-isolated patients with COVID-19 and control participants., Methods: Fifty-five COVID-19 and 44 control participants underwent smell testing, using Burghart Sniffin' Sticks 'Screening 12 Test'. Participants also rated their smelling capability on the numerical scale. Differences between groups and correlation between smell loss and time from acute onset of symptoms were tested, as well as correlation between results of smell test and subjective assessment of smell., Results: Hospitalised patients with COVID-19 correctly determined 6.5/12 odorants compared with 10/12 in the self-isolated and 11/12 in the control group (p<0.001). Hyposmia or anosmia were present in 87.5% of hospitalised and 29.0% of self-isolated patients (p<0.001). The correlation between subjective self-assessment and results of smell testing was non-significant in both groups of patients with COVID-19, while there was a moderate positive correlation (p=0.001, Spearman's correlation coefficient=0.499) in control participants., Conclusion: Contrary to some previous reports suggesting that the presence of olfactory loss may predict milder course of disease, our study found that a vast majority of hospitalised patients with COVID-19 had prominent olfactory impairment. The absence of correlation between self-rated and objective smell evaluation in patients with COVID-19 indicates that subjective smell assessment is unreliable., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2022. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Progressive supranuclear palsy (PSP) features parkinsonism characterized by early postural instability, falls and prominent eye movement abnormalities that consist of saccadic slowing, followed by gaze limitation. Nystagmus is not considered typical for PSP, being more commonly associated with multiple system atrophy., Objectives: To describe the prevalence and phenomenology of nystagmus in patients with PSP., Methods: 42 patients with probable PSP underwent detailed clinical eye movement examination. Patients with nystagmus performed video-nystagmography. T-test, Chi-Square test and Wilcoxon signed-rank test were used to test differences in demographic data, disease duration and PSP subtype between patients with and without nystagmus, and for analysis of video-nystagmographic data., Results: Among 42 patients with PSP, we identified 15 patients (35,7%) with gaze-evoked nystagmus, predominantly horizontal. Clinically, 10/15 patients had symmetrical or asymmetrical gaze - evoked nystagmus (Type 1), while 5/15 patients had dissociated gaze-evoked nystagmus related to internuclear ophthalmoplegia (Type 2). Nystagmus and eye movement abnormalities were further characterized by video-nystagmography. There was no significant difference in age, disease duration or PSP subtypes between patients with and without nystagmus., Conclusion: Central nystagmus is present in more than a third of patients with progressive supranuclear palsy. It may present as symmetrical or asymmetrical gaze-evoked nystagmus or as dissociated gaze-evoked nystagmus related to internuclear ophthalmoplegia and probably arises from neurodegeneration of the neural integrator. Nystagmus in PSP has been a hitherto under-described feature and its presence should not deter clinicians from a diagnosis of PSP., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Competing Interests: Conflict of interest None.

Background: Demographic and clinical studies imply that female sex may be protective for PD, but pathophysiological evidence to support these observations is missing. In early PD, functional changes may be detected in primary motor cortex using transcranial magnetic stimulation., Objective: We hypothesised that if pathophysiology differs between sexes in PD, this will be reflected in differences of motor cortex measurements., Methods: Forty-one newly diagnosed PD patients (22 males, 19 females) were clinically assessed using MDS-UPDRS part III, and various measures of cortical excitability and sensorimotor cortex plasticity were measured over both hemispheres, corresponding to the less and more affected side, using transcranial magnetic stimulation. Twenty-three healthy (10 men, 13 women) participants were studied for comparison., Results: Among patients, no significant differences between sexes were found in age, age of diagnosis, symptom duration, and total or lateralized motor score. However, male patients had disturbed interhemispheric balance of motor thresholds, caused by decreased resting and active motor thresholds in the more affected hemisphere. Short interval intracortical inhibition was more effective in female compared to male patients in both hemispheres. Female patients had a preserved physiological focal response to sensorimotor plasticity protocol, whereas male patients showed an abnormal spread of the protocol effect., Conclusion: The study provides one of the first neurophysiological evidences of sex differences in early PD. Female patients have a more favorable profile of transcranial magnetic stimulation measures, possibly reflecting a more successful cortical compensation or delayed maladaptive changes in the sensorimotor cortex. © 2019 International Parkinson and Movement Disorder Society., (© 2019 International Parkinson and Movement Disorder Society.)

Background: We have commonly observed involuntary jerks and tremor in patients with motor neuron disease (MND), even though these features are not considered typical for the disease. Objectives: We conducted prospective clinical and electrophysiological study to explore the prevalence, phenomenology and pathophysiology of involuntary movements in MND. Methods: Seventy-four consecutive patients were clinically examined and video-recorded. Based on regularity and distribution, movements observed at rest position were classified as minipolymyoclonus (MPMC) or rest thumb tremor (RTT) and movements present during action as action MPMC or action tremor. In 11 patients with tremor, accelerometry was recorded at (a) rest position, (b) with arms outstretched (postural condition) and (c) at postural condition with 500 g mass attached to the hand. Results: Involuntary movements were present in 54 patients (73%). Rest MPMC was present in 26 patients (35%), RTT in 22 patients (31%), action MPMC in 22 patients (30%) and action tremor in 20 patients (27%), with some overlap. Sixteen patients (22%) reported negative impact of involuntary movements on their ability to use hands. Regression model showed that lower distal muscle power and less prominent upper motor neuron involvement significantly increased the odds of MND patient having involuntary movements. Sex, age and disease duration did not significantly predict the occurrence of involuntary movements. At rest, tremor frequency ranged from 5.2 to 8.2 Hz, at postural position from 4.9 Hz to 7.6 Hz and during postural position with mass attached from 3.6 Hz to 7.6 Hz. On the group level, tremor peak frequency statistically significantly decreased from 6.1 Hz to 5 Hz without versus with loading. Discussion and conclusions: Involuntary movements are very common yet largely overlooked feature of MND that may also have negative impact on patient's functional abilities. Lower distal muscle power increases and the presence of upper motor neuron signs decreases the probability of involuntary movements. Together with finding of decrease in tremor frequency with mass loading, these results suggest that generation of involuntary movements is of peripheral origin.

Dystonia is common in the classic atypical parkinsonian disorders such as multiple system atrophy, progressive supranuclear palsy and corticobasal degeneration, and to a lesser extent in dementia with Lewy bodies. Its clinical phenomenology, including body distribution, timing of appearance, severity, and relationship to dopaminergic and other medications may vary considerably within and between atypical parkinsonian disorders. From a pathophysiological standpoint, the coexistence of dystonia with parkinsonism challenges the functional model of the basal ganglia. Clinical recognition of specific dystonic features may assist in the differential diagnosis of atypical parkinsonian disorders and in distinguishing them from Parkinson's disease. The presence of dystonia in atypical parkinsonian disorders informs management decisions. Reduction or withdrawal of levodopa should be considered if there is a close relationship between the onset of dystonia with periods of high dopaminergic tone. Botulinum neurotoxin may be considered in focal presentations. We here provide an updated overview of dystonia arising in the setting of atypical parkinsonian disorders, summarizing relevant clinical and clinicopathological studies, underlying pathophysiological mechanisms, diagnostic clues and potential pitfalls in the diagnosis. Finally, we suggest a tailored therapeutic approach for the management of these patients., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Background: Motivational improvement of movement speed in Parkinson's disease (PD) is observed in life-threatening situations and has been empirically demonstrated in experimental studies using reaction time paradigms., Objectives: To address two clinically relevant questions: first, if in PD, motivational modulation through provision of monetary incentive on a sorting task that approximates performance on everyday life tasks affects movement speed. Second, how this effect is compared between PD patients treated with medication or subthalamic deep brain stimulation., Methods: We used the Card Arranging Reward Responsivity Objective Test that shares component processes with everyday life tasks to compare reward responsivity of movement speed in 10 PD patients with STN-DBS, 10 nonoperated medicated PD patients, both OFF and ON their usual medications/stimulation, and 11 age-matched healthy controls., Results: Despite longer disease duration and more severe motor symptoms, STN-DBS PD patients with the stimulator turned ON showed greater improvement of movement speed with the prospect of monetary incentive compared to both medicated PD patients and healthy participants., Discussion: The effect of monetary incentive on movement speed in PD patients is more pronounced with STN-DBS than dopaminergic medications, suggesting that motivational modulation of movement speed may be enhanced as a direct consequence of STN stimulation.

Competing Interests: Competing interests: None declared.

Despite accumulating evidence of inter and intraindividual variability in response to theta burst stimulation, it is widely believed that in therapeutic applications, repeated sessions can have a "build-up" effect that increases the response over and above that seen in a single session. However, strong evidence for this is lacking. Therefore, we examined whether daily administration of intermittent theta burst stimulation (iTBS) over the primary motor cortex induces cumulative changes in transcranial magnetic stimulation measures of cortical excitability, above the changes induced by sham stimulation. Over five consecutive days, 20 healthy participants received either active iTBS or sham stimulation. Each day, baseline measures of cortical excitability were assessed before and up to 30 min after the intervention. There was no significant difference in the rate of response between iTBS and sham stimulation on any of the 5 days. There was no iTBS specific cumulative increase of corticospinal excitability. The likelihood that an individual would remain a responder from day-to-day was low in both groups, implying high within-subject variability of both active and sham iTBS after-effects. In contrast, we found a high within-subject repeatability of resting and active motor threshold, and baseline motor-evoked potential amplitude. In summary, sham stimulation has similar effect to active iTBS on corticospinal excitability, even when applied repeatedly for 5 days. Our results might be relevant to research and clinical applications of theta burst stimulation protocols., (© 2018 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.)

Background: Surround inhibition (SI) in the motor system has been described to be decreased in patients with focal hand dystonia (FHD) but no evidence currently exists for patients with cervical dystonia (CD)., Objective: To characterise the SI profiles in three groups of participants: healthy volunteers, patients with FHD and patients with CD. To provide sample size calculations for future studies., Methods: SI was assessed using Transcranial Magnetic Stimulation (TMS) in 31 right-handed healthy participants, 11 patients with CD and 12 patients with FHD. In addition data of SI in patients with FHD were extracted from previously published and analysed for sample size calculations and assessment of SI variability., Results: No statistically significant difference in SI was found amongst the groups (healthy, FHD, CD). Analysis of combined current and previous data suggests that our study and all prior studies were underpowered. At least 26 participants in each group are required for a simple comparison of two groups. Analysis of published data indicated that SI is more variable in FHD patients compared to healthy controls., Conclusions: The highly variable SI in patients with dystonia can confound statistical comparisons of mean differences. Larger studies are needed to assess SI in dystonia and to explore the origins of its variability., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Persistent placoid maculopathy (PPM) is a bilateral inflammatory chorioretinopathy characterized by long-standing plaque-like macular lesions. No systemic manifestations have been reported to date. We describe a case of PPM complicated by cerebral vasculitis, suggesting that neurological symptoms, including headache, should be enquired about in all PPM subjects.

Objective: The subthalamic nucleus (STN) is part of the motor, associative, and limbic cortico-striatal circuits through which it can influence a range of behaviours, with preclinical and clinical evidence suggesting that the STN is involved in motivational modulation of behaviour. In the present study, we investigated if in Parkinson's disease (PD) motivational modulation of movement speed is altered by deep brain stimulation (DBS) of the STN (STN-DBS)., Methods: We studied the effect of monetary incentive on speed of movement initiation and execution in a computer-based simple reaction time task in 10 operated patients with Parkinson's disease using a STN DBS ON/OFF design and also in 11 healthy participants., Results: Prospect of reward improved speed of movement initiation in PD patients both with STN-DBS ON and OFF. However, only with STN-DBS ON, the patients showed greater speeding of initiation time with higher reward magnitude, suggesting enhanced responsivity to higher reward value. Also, on the rewarded trials, PD patients ON stimulation made more anticipation errors than on unrewarded trials, reflecting a propensity to impulsive responses triggered by prospect of reward by subthalamic stimulation. The motivational modulation of movement speed was preserved and enhanced in PD with STN-DBS., Conclusion: Motivational modulation of movement speed in PD is maintained with STN-DBS, with STN stimulation having a further energizing effect on movement initiation in response to greater incentive value. Our results suggest that STN plays a role in integrating motivational influences into motor action, which may explain some previous reports of STN-DBS induced impulsivity with increased motivational salience of stimuli., (Copyright © 2016. Published by Elsevier Ltd.)

Background: The natural fluctuation of motor symptoms of Parkinson's disease (PD) makes judgement of any change challenging and the use of clinical scales such as the International Parkinson and Movement Disorder Society (MDS)-UPDRS imperative. Recently developed commodity mobile communication devices, such as smartphones, could possibly be used to assess motor symptoms in PD patients in a convenient way with low cost. We provide the first report on the development and testing of stand-alone software for mobile devices that could be used to assess both tremor and bradykinesia of PD patients., Methods: We assessed motor symptoms with a custom-made smartphone application in 14 patients and compared the results with their MDS-UPDRS scores., Results: We found significant correlation between five subscores of MDS-UPDRS (rest tremor, postural tremor, pronation-supination, leg agility, and finger tapping) and eight parameters of the data collected with the smartphone., Conclusions: These results provide evidence as a proof of principle that smartphones could be a useful tool to objectively assess motor symptoms in PD in clinical and experimental settings.

Background: A number of neurophysiological abnormalities have been described in patients with Parkinson's disease, but very few longitudinal studies of how these change with disease progression have been reported. We describe measures of motor cortex inhibition and plasticity at 6 and 12 mo in 12 patients that we previously reported at initial diagnosis. Given the well-known interindividual variation in these measures, we were particularly concerned with the within-subject changes over time., Methods: Patients were assessed clinically, and transcranial magnetic stimulation (TMS) was used to measure motor cortical excitability, inhibition (short interval intracortical inhibition, cortical silent period), and plasticity (response to excitatory paired associative stimulation protocol) in both hemispheres. All measurements were performed 6 mo and 12 mo after the baseline experiments., Results: Asymmetry in clinical motor symptoms was reflected in asymmetry of plasticity and inhibition. In the group as a whole, little change was seen in any of the parameters over 12 mo. However, analysis of within-individual data showed clear correlations between changes in clinical asymmetry and asymmetry of response to paired associative stimulation protocol and cortical silent period., Conclusions: Longitudinal changes in cortical silent period and response to paired associative stimulation protocol in Parkinson's disease reflect dynamic effects on motor cortex that are related to progression of motor signs. They are useful objective markers of early disease progression that could be used to detect effects of disease-modifying therapies. The decline in heightened plasticity that was present at disease onset may reflect failure of compensatory mechanisms that maintained function in the preclinical state., (© 2015 International Parkinson and Movement Disorder Society.)