جستجوی مقالات مرتبط با کلیدواژه « Cerebellum » در نشریات گروه « پزشکی »

Today, high-voltage (HV) lines create a pernicious environment for humans living or working in the vicinity and even under these lines. The male rhesus monkey is used to investigate the effects of fields produced by HV towers. This study examines the function and level of impact in rhesus monkeys’ brains from the cerebellum’s cognitive, biological, and structural perspective. 

Two monkeys have been used, one as a control and the second as a test. The monkey under test was subjected to a simulated HV electrical field of 3 kV/m, 4 hours a day, for 1 month. Behavioral tests were performed using a device designed and built for this purpose. Concentration analysis of adrenocorticotropic hormones (ACTH) and inspection of glucocorticoid receptor gene’s (GR) expression were performed by the reverse transcription polymerase chain reaction method. Changes in cerebellar anatomy were examined with magnetic resonance imaging (MRI). All tests were performed before and after the study period and compared with the control monkey. 

Cognitive tests showed a significant reduction for the monkey exposed to the HV electrical field in the first week after imposition compared with the same time before. Also, the expression of the GR gene decreased, and the concentration of ACTH hormone in plasma increased. Surveying the level of cerebral MRI images did not show any difference, but hemorrhage was evident in a part of the cerebellum. 

The tested monkey’s cognitive, biological, and MRI results showed a decrease in visual learning and memory indices.

Mobile devices are sources of electromagnetic fields (EMFs) that cause increasing concern among scientists about human health, especially with the long-term use of mobile phones.With regard to this issue, the potential adverse health effects, particularly on brain function have raised public concern. There is considerable evidence that natural compounds have neuro-protective effects due to their antioxidant and anti-inflammatory properties. Growing evidence suggests that crocin as a natural bioactive compound can be considered a potential therapeutic agent against various neurologic disorders. Therefore, the present study investigated the effects of crocin on the cerebellum after exposure to EMF.

Twenty-four Male Balb/c mice were divided into control group, EMF group (2100 MHZ), EMF +Crocin group (2100 MHZ+50 mg/kg), and crocin group (50 mg/kg). The animals in the EMF and EMF+Crocin groups were exposed continuously for 30 days to an EMF 120 min/day. After 30 days, cerebellar cortex was evaluated by histomorphometric and immunohistochemical methods.

The results showed that 30 days of exposure to EMF had no significant effect on Purkinje cell size. However, EMF reduced significantly the diameter of astrocytes and increased Glial fibrillary acidic protein (GFAP) expression compared to the controls (p<0.05). Our findings also indicated that crocin treatment could improve the diameter of astrocytes and normalize GFAP expression (p<0.05).

This study concluded that 2100-MHz EMF caused adverse effects on the cerebellum through astrocyte damage and crocin could partially reverse the EMF-related adverse effects.

Spaceflight poses unique physiological stressors, including circadian rhythm disruption, which can impact astronaut health and brain function.

This study investigated the effects of rapid day/night changes on cholinesterase activity in the rats’ cerebellum and prefrontal cortex.

Rats were divided into 2 groups (n = 8 per group): Control and circadian disruption with a 45-minute light/45-minute dark cycle. After 14 days of intervention, the cerebellum and prefrontal cortex were harvested from each rat. The samples were washed in ice-cold normal saline solution, weighed, homogenized in phosphate buffer using 1 ml of buffer per 100 mg of tissue, and centrifuged. Moreover, the supernatants were used for the measurement of cholinesterase activity by the photometric method.

Mean cholinesterase activity was significantly lower in rats exposed to circadian disruption than in the control group (P < 0.05).

It seems that cholinesterase activity in rats’ cerebellum and prefrontal cortex reduces following exposure to rapid light/dark rhythm.

Multiple sclerosis (MS) is an inflammatory demyelinating and neurodegenerative disorder of the central nervous system, which is associated with brain atrophy and volume changes in some brain structures. This study aimed to compare the volume of the basal ganglia, thalamus, cerebellum, and brainstem in patients with relapsing-remitting MS with that of the control group using magnetic resonance imaging (MRI).

In this cross-sectional study, MRI brain scans were obtained from 25 patients with relapsing-remitting MS and 25 healthy control subjects. Volumetric analyses were performed using Brain Suite software.

The mean age of the MS and the control groups was 33.96±8.75 and 40.40±8.72, respectively. No statistically significant difference was found in gender (P=0.747). The bilateral putamen and caudate nuclei volumes were significantly higher in the case group than in the control group (P<0.001). Moreover, lower the volume of the brainstem, cerebellum, bilateral thalamus, and globus pallidus were identified in the MS patients compared to the control group (P<0.001). There was an inverse correlation between the disease and treatment duration with the thalamus and cerebellum volume in MS patients (P=0.001). Treatment duration also had an inverse correlation with brainstem volume (P=0.047).

The volume of some structures of the brain, including globus pallidus, thalamus, cerebellum, and brainstem is lower in MS and can be one of the markers of disease progression and disability among MS patients.

We investigated the sodium benzoate effects on motor coordination, cerebellar purkinje cells, and oxidative stress in Wistar rats’ brain.

Male Wistar rats were divided into three groups of six each. Group 1 given 0.5ml distilled water; Group 2 given 100 mg/kg sodium benzoate (NaB); and Group 3given 300 mg/kg NaB. The NaB solution was given orally for 28 days. Hanging wire and footprint tests were performed. Upon sacrifice, the cerebellar tissue samples were collected, and malondialdehyde assay was performed. Histological analyses of the cerebellar sections stained with H&E, cresyl fast violet and glial fibrillary acidic protein were performed. The Purkinje cells were also counted in the cerebellar samples.

On the hanging wire tests, control rats and those given NaB100mg/kg groups took longer time to fall off, compared to those given NaB300mg/kg (P˂0.05). Footprint tests revealed changes in the animals’ stance and stride patterns. The base width, stride length, and overlap length showed no significant differences across the three groups. The NaB at 300mg/kg adversely affected the cerebellar Purkinje cells, reduced the numbers, and caused distortions. The nissl substances were stained lightly and the GFAP expression indicated gliosis, particularly in rats given NaB300mg/kg. The oxidative stress indicators increased after NaB treatment at 300mg/kg but not at 100mg/kg.

NaB at 300mg/kg altered the cerebellar Purkinje cells, increased the oxidative stress, and affected the motor coordination. The group treated with NaB100mg/kg exhibited fewer adverse effects than those with NaB300mg/kg.

Cerebellar infarction is an ischemic or hemorrhagic type episode involving the three main cerebellar arteries. An infarction in each of these arteries causes different but common symptoms, requiring a particularly important contribution of physiotherapy to its treatment. This overview aimed to investigate the effectiveness of physiotherapy programs on the symptoms of patients with cerebellar infarction.

A literature search was performed using eight databases and the keywords, including physiotherapy, physical therapy, rehabilitation, therapeutic exercise, exercise, cerebellar infarct, cerebellar infarction, and cerebellar blockage. The selection process of the final studies was carried out after setting inclusion and exclusion criteria and separately by two reviewers. 

Out of 1477 initial records, six studies met the inclusion criteria for this overview. Interventions focused on a balance training program and walking training, as opposed to a treadmill training program, seem to improve symptoms in these patients. Also, task-oriented approach was a promising method of rehabilitation.

Physiotherapy has a beneficial effect on the symptoms of patients with cerebellar infarction and should be considered for the overall recovery of the patient. However, future research is needed due to the small number of studies and to find therapeutically proven forms of intervention.

Diabetes is a metabolic disorder that affects the development of the central nervous system and plays an important role in learning and memory. Diabetes increases the reactive oxygen species (ROS) level in cells and changes the expression of several genes, including SYP, BDNF, PAX7, and SYNCAM1, through the FOXO transcription factor. This study was done to assess the effect of diabetes on morphometric indexes of the cerebellar cortex and gene expression in mice. Diabetes was induced in twelve adult, male C57BL mice using an injection of streptozotocin. After two months, the mice were dissected, and the cerebellum was stored for further analysis. For the morphometric analysis, tissue sections were stained with cresyl violet and examined with a light microscope. For gene expression analysis, the RNA was extracted, and cDNA was synthesized. The mRNA levels of SYP, BDNF, PAX7, and SYNCAM1 genes were measured by the real-time PCR method. The thickness of the molecular layer and Purkinje layer, and the number of Purkinje and granular cells in the diabetic group were significantly reduced compared to controls P<0.0 1). The area, perimeter, and diameter of Purkinje cells in the diabetic group were significantly reduced compared to controls P<0.0 1). The expression of PAX7, SYP, and BDNF genes of the diabetic group was significantly reduced. However, SYNCAM1 expression in the cerebellum of the diabetic group was significantly increased compared to controls (P<0.05). Induced diabetes in mice can decrease the expression of memory-related genes in the cerebellum. Also, these genes affect the morphology and thickness of the cerebellum.

We previously reported that datumetine possesses binding affinity with N-methyl-D-aspartate receptor (NMDAR) and that 14-day exposure to datumetine altered NMDAR signaling by mimicking glutamate toxicity. Here, we investigated the potential neuroprotective effect of a single shot of a low dose of datumetine administration in BALB/c mice.

30 male adult BALB/c mice were used for the study. The mice were randomly divided into three groups of ten mice each with an intraperitoneal injection of 0.1 mL of 10% DMSO for the Vehicle group, Datumetine group were administered 0.1 mg/kg body weight (bw) of datumetine and MK-801+Datumetine group were administered 0.5 mg/kg bw of MK-801 (to block NMDAR) followed by 0.1 mg/kg bw of datumetine after 30 minutes. 24 hours after administration, mice were euthanized in an isoflurane chamber followed by perfusion with 1X PBS. Brains were excised and stored at -200C till further processing. Mice designated for IHC were further perfused with 4% PFA and brain excised and stored in 4% PFA till further processing. NMDAR signalling molecules expression was evaluated in frozen brain samples and the fixed brain samples were stained for neuron, vGlut and NMDAR subtypes.

Relative to vehicle (Veh), datumetine downregulate calcium calmodulin kinase II alpha (CamKIIα) expression in the hippocampus and prefrontal cortex (PFC) but not in the cerebellum, cyclic AMP response element binding protein (CREB) was also upregulated only in the PFC but phosphorylated CREB (pCREB) was also upregulated in three brain regions observed, while brain-derived neurotrophic factor (BDNF) was only upregulated in hippocampus and PFC of Datumetine relative to vehicle (Veh). On the other hand, dizocilpine (MK-801) reversed some of the effects of datumetine in the observed brain regions. No major histological alterations were observed in the different brain regions immunohistochemically.

We conclude that a low dose of datumetine moderately enhances NMDAR activity. This showed the neuroprotective potentials of low datumetine exposure.

The neurotoxic effects of aluminum exposure during the critical period of neurodevelopment have been well documented. This study investigated the known protective effects of calcium supplementation on the cerebellum of juvenile Wistar rats following aluminum-induced neurotoxicity during lactation.

Four groups of juvenile rats were exposed via lactation to distilled water (control group), aluminum (40 mg/kg/d), calcium supplement (50 mg/kg/d), and a combination of both aluminum and calcium from postnatal day 4 to day 28. The cerebella of the animals were excised to access the levels of antioxidant enzymes (superoxide dismutase [SOD], glutathione peroxidase [GPx]), lipid peroxidation (malondialdehyde), histomorphological alterations (hematoxylin and eosin staining), Nissl profile (cresyl fast violet staining), and glial activation (glial fibrillary acidic protein immunohistochemistry).

Lactational aluminum significantly decreased the activities of superoxide dismutase and glutathione peroxidase while exacerbating lipid peroxidation and reactive astrocyte in cerebellar lysates. Lactational calcium supplementation normalized the activities of SOD and GPx, thereby preventing excessive lipid peroxidation and glial activation. Despite no apparent changes in the general histology of the cerebellum, aluminum-induced chromatolysis changes in the Purkinje cell layer, which was counteracted by the antioxidant propensities of calcium supplementation.

These findings support that calcium supplementation significantly protects the cerebellum against aluminum-induced oxidative stress, chromatolysis, and neuroinflammation.

This series lists a pictorial quiz pertaining to identification of normal and abnormal anatomical structures and landmarks at a given level on computed tomography (CT). Readers are expected to identify and appreciate the changes from normal anatomy and variations of a given pathology. The main structures assessed in this quiz are the pons, ventricular system of the brain, and the basal cisterns. Particular emphasis is placed on the presentations of intra-cranial haemorrhages, particularly sub-arachnoid and epidural haemorrhages, and masses around the region of the pons, midbrain and cerebellum. There is also a question pertaining to increased intracranial pressure. Differential diagnoses are also given where necessary to guide clinical practice and further learning. A Points to remember section details key clinical pearls. Furthermore, key resources have been cited as recommendations for further reading. It is anticipated that this series will enhance the understanding of sectional anatomy of the brain to aid in brain CT interpretation.

Drug craving is a major problem in addiction treatment. Neuroimaging research has revealed various areas for drug craving, among which two key areas are the Dorsolateral Prefrontal Cortex (DLPFC) and the cerebellum. The DLPFC is involved in different cognitive tasks, such as inhibitory control over seductive options that promise an immediate reward. The cerebellum is related to cognition and memory and activated by drug-related cues. Therefore, we decided to study the effect of Transcranial Direct Current Stimulation (tDCS) on six different protocols in reducing drug craving and increasing cognitive functions in methamphetamine addicts. 

The present study is quasi-experimental, with a pre-test-post-test design and a control group. Based on a simple sampling method, 15 male methamphetamine addicts were recruited from two rehabilitation centers in Tehran City, Iran. The participants were aged 18-65 years with a minimum of 12-month history of methamphetamine dependence. The Visual Analog Scale (VAS), the go/no-go task and the n-back task were administered before and after a single session of tDCS. The tDCS was applied on six protocols: 1) the right DLPFC anodal and the left DLPFC cathodal stimulation, 2) the right DLPFC cathodal and the left DLPFC anodal stimulation, 3) the right DLPFC anodal and the right arm cathodal stimulation, 4) the left DLPFC anodal and the left arm cathodal stimulation, 5) the right cerebellar hemisphere (O2) anodal and the left cerebellar hemisphere (O1) cathodal stimulation, and 6) the right cerebellar hemisphere (O2) cathodal and the left cerebellar hemisphere (O1) anodal stimulation. The data were analyzed by covariance method using SPSS software v. 22.

Study results indicated that while single-session tDCS effects on craving were not significant, it increased cognitive inhibition, especially in protocol 2: the right DLPFC cathodal and the left DLPFC anodal stimulation.

Single-session tDCS affects craving insignificantly, but it can increase cognitive inhibition significantly. These findings support the results of previous studies on the effects of brain stimulation on reducing drug craving in other drug-type settings.

Addiction is a mental disorder that has many adverse effects on brain health. It alters brain structure and deteriorates brain functionality. Impairment of brain cognition in drug addiction is illustrated in many previous works; however, olfactory perception in addiction and, in particular, its neuronal mechanisms have rarely been studied. 

In this experiment, we recruited 20 heroin addicts and 20 normal controls of the same sex, age, handedness, and socioeconomic status and compared their brain function while perceiving non-craving odors during the functional magnetic resonance imaging (fMRI). We intended to define the default olfactory system performance in addicts compared to healthy people. 

Our study showed an overall larger activation in addicts when processing olfactory stimuli. In particular, and when comparing the two groups, the right anterior cingulate and right superior frontal gyrus had higher activations than normal, whereas the left lingual gyrus and left cerebellum showed stronger activations in the addicts. 

The result of this study can unveil the missing components in addiction brain circuitry. This information is helpful in better understanding the neural mechanisms of addiction and may be advantageous in designing programs for addiction prevention or clinical treatment.

This study aimed to determine the poten cy of kebar grass ethanol extract to overcome an increase in cerebellar neuronal cell necrosis, which has an impact on decreasing motor reflex function and spatial memory of mice from lactating mothers exposed to carbofuran.

 Forty lactating mice were divided into four groups, 10 each; including control, T1 (carbofuran 0.0125 mg/day), T2 (vitamin C 5 mg + carbofuran 0.0125 mg/day), T3 (kebar grass extract 3.375 mg + carbofuran 0.0125 mg/day). The mice were orally administered with carbofuran, vitamin C, and kebar grass extract on days 0 to 14 postnatal. On the 15 th day, brains of the mice were necropsied to measure the levels of malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione (GSH), H&E staining; motor reflex tests were performed on 10-day-old mice, and the mice aged 30 days were tested on their swimming and spatial memory.

Carbofuran caused an increase in MDA, GSH, neuronal cell necrosis, surface righting reflex, a decrease in SOD, swimming ability, and spatial memory. Kebar grass extract and vitamin C administration decreased MDA, GSH, neuron necrosis, surface righting reflex, and increased SOD, swimming ability, and spatial memory.

Exposing to carbofuran in lactating mice caused brain oxidative stress, impaired motor reflexes, and spatial memory in mice offspring. Ke bar grass extract and vitamin C administration prevented brain oxidative stress and inhibited disorders in motor reflexes, and spatial memory in mice offspring. Kebar grass extract administration was more effective than vitamin C.

Cerebellum has long been known to modulate not only motor coordination but also affective and cognitive functions. Thisstudy aimed to assess the impact of middle cerebellar peduncle (MCP) lesions on affective and cognitive function in patients with multiple sclerosis (MS).

This was a cross-sectional study conducted on patients with relapsing-remitting MS (RRMS). All patients were subjected to 3-Tesla magnetic resonance imaging (3T MRI), brief international cognitive assessment for MS (BICAMS), and Depression, Anxiety, and Stress Score-21 (DASS-21) upon recruitment.

Of the 30 patients recruited, 33.3% and 36.7% had right and left MCP lesions, respectively. Patients with right MCP lesions had significantly worse symbol digit modality test (SDMT) scores (P = 0.036), worse California verbal learning test (CVLT) immediate recall scores (P = 0.011), and worse CVLT delayed free recall scores (P = 0.049), whereas patients with left MCP lesions had lower DASS-21 scores (P < 0.005). On multivariate regression analysis,the presence of left MCP lesion was associated with an 8.9-point reduction in DASS-21 scores (CI: -16.985- -0.805, P = 0.033), whereas right MCP lesions did not have an independent effect on BICAMS scores after adjustment for age and educational level.

Left MCP lesions were associated with significantly lower DASS-21 scores, whereas none of the MCP lesions had an independent impact on cognition