Microfabricated disk technology: rapid scale up in midbrain organoid generation

By providing a three-dimensional in vitro culture system with key features of the substantia nigra region in the brain, 3D neuronal organoids derived from human induced pluripotent stem cells (iPSCs) provide living neuronal tissue resembling the midbrain region of the brain. However, a major limitation of conventional brain organoid culture is that it is often labor-intensive, requiring highly specialized personnel for moderate throughput. Additionally, the methods published for long-term cultures require time-consuming maintenance to generate brain organoids in large numbers. With the increasing need for human midbrain organoids (hMOs) to better understand and model Parkinson′s disease (PD) in a dish, there is a need to implement new workflows and methods to both generate and maintain hMOs, while minimizing batch to batch variation. In this study, we developed a method with microfabricated disks to scale up the generation of hMOs. This opens up the possibility to generate larger numbers of hMOs, in a manner that minimizes the amount of labor required, while decreasing variability and maintaining the viability of these hMOs over time. Taken together, producing hMOs in this manner opens up the potential for these to be used to further PD studies.

Pontine and extrapontine myelinolysis secondary to alcoholism: A case report.

Context: Osmotic demyelination syndrome (ODS) is rare, acute, severe and non-inflammatory. It is caused by the demyelination of neurons with the preservation of axons. It is called central pontine myelinolysis (CPM) when it affects the central pontine region and extra-pontine myelinolysis (EPM) when it affects other areas. Few cases of ODS due to non-electrolytic causes are reported. Case report: 54-year-old man with a history of heavy drinking. After about 24 hours of alcohol withdrawal, he developed generalized tonic-clonic seizures, associated with a lower level of consciousness. Protective orotracheal intubation was performed and the use of anti-crisis drugs was initiated. After sedation was switched off and mechanical ventilation was set to minimum parameters, the patient remained comatose and with convergence-retraction nystagmus movements. A skull MRI was performed, which showed lesions compatible with CPM and EPM. There was no variation in the patient’s plasma sodium during hospitalization. Conclusion: this is a patient with no evidence of any significant hydro-electrolyte disturbance and who presented a compatible neurological condition and neuroimaging characteristic of CPM / EPM. There is no specific clinical treatment for this pathology. Furthermore, the patient presents with the finding of convergence-retraction nystagmus, possibly explained by atrophy of the dorsal midbrain region.

Epstein-Barr virus meningoencephalitis in a immunocompetent child

Introduction: Meningoencephalitis caused by the Epstein-Barr virus (EBV) is a rare neurological entity, most often related to the latent reactivation of thevirus associated with immunosuppression. The clinic varies between encephalitis, meningitis, cerebellitis, neuritis and transverse myelitis. The prognosis is good, with 85% of patients returning to baseline levels. Case report: We attend to a 11-month-old male patient, proper neuropsychomotor development, with reports of fever and odynophagia, without improvement with antibiotic therapy. He had a focal epileptic seizure. Upon admission, he presented a new similar event, with control after use of diazepam and intravenous phenobarbital. At the neurological examination carried out after improving the level of consciousness, the patient was alert. He presented axial hypotonia, dystonic posture in flexion of the right upper limb, with preserved strength. He showed no meningeal signs. The cerebrospinal fluid revealed 61 mg/dL of glucose, 57 mg/dL of proteins and 65/mm³ of leukocytes (90% of lymphocytes). Acyclovir, ceftriaxone, and dexamethasone were started, with improvement. Magnetic resonance imaging revealed: FLAIR hyper signal injury, with diffusion restriction, in the left caudate nucleus, left lentiform and ipsilateral anterior midbrain region. Electroencephalogram with diffuse attenuation of baseline electrical activity. The main diagnostic hypothesis was meningoencephalitis secondary to EBV infection, with confirmatory PCR-DNA. Conclusion: The report illustrates the need for attention to a rare infectious etiology in atypical presentation of meningoencephalitis.

Rapid Immunohistological Measurement of Tyrosine Hydroxylase in Rat Midbrain by Near-Infrared Instrument-Based Detection

We present a robust, fresh-frozen approach to immunohistochemistry (IHC), without committing the tissue to IHC via fixation and cryopreservation while maintaining long-term storage, using LiCor-based infrared (IR) quantification for sensitive assessment of TH in immunoreacted mid-brain sections for quantitative comparison across studies. In fresh-frozen tissue stored up to 1 year prior to IHC reaction, we found our method to be highly sensitive to rotenone treatment in 3-month-old Sprague-Dawley rats, and correlated with a significant decline in rotarod laten-cy-to-fall measurement by approximately 2.5 fold. The measured midbrain region revealed a 31% lower TH signal when compared to control (p<0.01 by t test, n=5). Bivariate analysis of in-tegrated TH counts versus rotarod latency-to-fall indicates a positive slope and modest but sig-nificant correlation of R2=0.68 (p<0.05, n=10). These results indicate this rapid, instrument-based quantification method by IR detection successfully quantifies TH levels in rat brain tissue, while taking only 5 days from euthanasia to data output. This approach also allows for the identifica-tion of multiple targets by IHC with the simultaneous performance of downstream molecular analysis within the same animal tissue, allowing for the use of fewer animals per study.

Peripheral T cell lymphoma after chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS): a case report

Background Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) is an inflammatory disorder in the central nervous system (CNS) with distinct clinical, radiological, and pathological characteristics. The pathophysiology of CLIPPERS still remains unclear. Because a few cases about lymphoma mimicking the manifestations of CLIPPERS were reported and the prognosis of lymphoma is much worse, early identification of lymphoma is very important. Case presentation A 31-year-old woman was admitted with 3 months’ history of diplopia, dizziness, gait ataxia, and right facial numbness. The diagnosis of CLIPPERS was established based on the finding of punctate enhancing lesions in the cerebellum, thalamus, pons, medulla, and midbrain region in magnetic resonance imaging (MRI), together with the favorable clinical and radiological responses to corticosteroids. However, she was diagnosed as peripheral T cell lymphoma, not otherwise specified (PTCL-NOS) by the pulmonary nodular and the skin biopsy almost 10 years later, and she got complete remission within 1 year after chemotherapy. Conclusion We report the first case of CLIPPERS developing PTCL-NOS. This case proposes that when brain biopsy was difficult to achieve, biopsies in extra-cerebral lesions under the assisting examination of positron emission tomography-computed tomography (PET-CT) can be helpful in further identification.

Peripheral T cell lymphoma after chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS): A case report

Background Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) is an inflammatory disorder in the central nervous system (CNS) with distinct clinical, radiological, and pathological characteristics. The pathophysiology of CLIPPERS still remains unclear. Because a few cases about lymphoma mimicking the manifestations of CLIPPERS were reported and the prognosis of lymphoma is much worse, early identification of lymphoma is very important. Case presentation A 31-year-old woman was admitted with 3 months’ history of diplopia, dizziness, gait ataxia and right facial numbness. The diagnosis of CLIPPERS was established based on the finding of punctate enhancing lesions in the cerebellum, thalamus, pons, medulla, and midbrain region in magnetic resonance imaging (MRI), together with the favorable clinical and radiological responses to corticosteroids. However, she was diagnosed as peripheral T cell lymphoma, not otherwise specified (PTCL-NOS) by the pulmonary nodular and the skin biopsy almost 10 years later, and she got complete remission within 1 year after chemotherapy. Conclusion We report the first case of CLIPPERS developing PTCL-NOS. This case proposes that when brain biopsy was difficult to achieve, biopsies in extra-cerebral lesions under the assisting examination of positron emission tomography-computed tomography (PET-CT) can be helpful in further identification.

Peripheral T cell lymphoma after chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS): A case report

Background Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) is an inflammatory disorder in the central nervous system (CNS) with distinct clinical, radiological, and pathological characteristics. The pathophysiology of CLIPPERS still remains unclear. Because a few cases about lymphoma mimicking the manifestations of CLIPPERS were reported and the prognosis of lymphoma is much worse, early identification of lymphoma is very important. Case presentation A 31-year-old woman was admitted with 3 months’ history of diplopia, dizziness, gait ataxia and right facial numbness. The diagnosis of CLIPPERS was established based on the finding of punctate enhancing lesions in the cerebellum, thalamus, pons, medulla, and midbrain region in magnetic resonance imaging (MRI), together with the favorable clinical and radiological responses to corticosteroids. However, she was diagnosed as peripheral T cell lymphoma, not otherwise specified (PTCL-NOS) by the pulmonary nodular and the skin biopsy almost 10 years later, and she got complete remission within 1 year after chemotherapy. Conclusion We report the first case of CLIPPERS developing PTCL-NOS. This case proposes that when brain biopsy was difficult to achieve, biopsies in extra-cerebral lesions under the assisting examination of positron emission tomography-computed tomography (PET-CT) can be helpful in further identification.

Precise Coordination of 3-dimensional Rotational Kinematics by Ventral Tegmental Area GABAergic Neurons

SummaryThe Ventral Tegmental Area (VTA) is a midbrain region implicated in a variety of motivated behaviors. However, the function of VTA GABAergic (Vgat+) neurons remains poorly understood. Here, using 3D motion capture, in vivo electrophysiology and calcium imaging, and optogenetics, we demonstrate a novel function of VTAVgat+ neurons. We found three distinct populations of neurons, each representing head angle about a principal axis of rotation: pitch, roll, and yaw. For each axis, opponent cell groups were found that increase firing when the head moves in one direction, and decrease firing in the opposite direction. Selective excitation and inhibition of VTAVgat+ neurons generate opposite rotational movements. The relationship between these neurons and head angle is degraded only at the time of reward consumption, at which point all head-angle related neuronal subpopulations show indistinguishable reward-related responses. Thus, VTAVgat+ neurons serve a critical role in the control of rotational kinematics while pursuing a moving target. This general-purpose steering function can guide animals toward desired spatial targets in any motivated behavior.

Peripheral T cell lymphoma after chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS): A case report

Background Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) is an inflammatory disorder in the central nervous system (CNS) with distinct clinical, radiological, and pathological characteristics. The pathophysiology of CLIPPERS still remains unclear. Because a few cases about lymphoma mimicking the manifestations of CLIPPERS were reported and the prognosis of lymphoma is much worse, early identification of lymphoma is very important. Case presentation A 31-year-old woman was admitted with 3 months’ history of diplopia, dizziness, gait ataxia and right facial numbness. The diagnosis of CLIPPERS was established based on the finding of punctate enhancing lesions in the cerebellum, thalamus, pons, medulla, and midbrain region in magnetic resonance imaging (MRI), together with the favorable clinical and radiological responses to corticosteroids. However, she was diagnosed as peripheral T cell lymphoma, not otherwise specified (PTCL-NOS) by the pulmonary nodular and the skin biopsy almost 10 years later, and she got complete remission within 1 year after chemotherapy. Conclusion We report the first case of CLIPPERS developing PTCL-NOS. This case proposes that when brain biopsy was difficult to achieve, biopsies in extra-cerebral lesions under the assisting examination of positron emission tomography-computed tomography (PET-CT) can be helpful in further identification.

Cortico-brainstem mechanisms of biased perceptual decision-making in the context of pain

Perceptual decision-making is commonly studied using stimuli with different physical properties but of comparable affective value. Here, we investigate neural processes underlying human perceptual decisions in the affectively rich domain of pain using a drift-diffusion model in combination with a probabilistic cueing paradigm. This allowed us to characterize a novel role for the dorsolateral prefrontal cortex (DLPFC), whose anticipatory responses reflecting a decision bias were dependent on the affective value of the stimulus. During intense noxious stimulation, these model-based anticipatory DLPFC responses were linked to an engagement of the periaqueductal gray (PAG), a midbrain region implicated in defensive responses including analgesia. Complementing these findings on biased decision-making, the model parameter reflecting sensory processing predicted subcortical responses (in amygdala and PAG) when expectations were violated. Our findings highlight the importance of taking a broader perspective on perceptual decisions and link decisions about pain with subcortical circuitry implicated in endogenous pain modulation.