No abstract

This study was aimed to assess: (1) the additive diagnostic utility of diffusion-weighted imaging (DWI) and magnetic resonance angiography (MRA) over conventional MRI in detecting brain lesions in patients with acute primary neuropsychiatric systemic lupus erythematosus (NPSLE), and (2) the relevance of their findings to the associated NP manifestations. Included were 34 patients with acute NPSLE with mean age of 33.26 ± 10.14 years and duration of illness of 3.33 ± 1.71 years. Clinical interviewing and psychiatric and cognitive evaluations were performed by applying the criteria of the diagnostic and statistical manual of mental health disorders criteria (DSM-IV), Stanford Binet Subset Testing, Mini-Mental State Examination and Wechsler Memory Scale-Revised. Serologic tests included looking for antinuclear antibodies, anti-double strand DNA, anti-phospholipid antibodies. Radiologic evaluation included conventional MRI, DWI and MRA. One or more NP manifestations were diagnosed in 28 patients, in which cognitive deficits were reported with headache, psychosis and CVS. Anti-phospholipid antibodies were reported in patients with CVS. Twenty patients (71.43 %) with primary NPSLE (n = 28) had MRI abnormalities in which hyperintense signals at subcortical and periventricular white matter and at the junction between the gray and white matter represented 75 % (n = 15) and with headache (n = 6), psychosis (n = 6) and acute confusional state (n = 3) with and without cognitive deficits, respectively. Moderate-sized infarctions with restricted diffusion in the distribution of middle cerebral arteries were represented in 35 % (n = 7) and with CVS, of them, 71.43 % (n = 5) had beading and focal narrowing of carotid arteries were consistent with vasculitis. Brain atrophy represented 20 % (n = 4) and with psychosis. Compared to those with normal MRI, patients with MRI abnormalities were older (P < 0.050) and had longer duration of illness (P < 0.050). To conclude, although DWI and MRA are helping in more precise etiopathologic diagnosis compared to conventional MRI, but their relevance to the present NP manifestations is still limited.

Aeolianites with a mixed clastic and carbonate detrital mineralogy are typical deposits of tropical coastal desert environments. These deposits are genetically related to transgressive–regressive cycles, with the shallow‐marine carbonate detrital component being deflated from the exposed seafloor during episodes of glacial sea‐level lowstands, transported and later accumulated onto more continental areas. A detailed investigation of the granulometric and petrographic properties of the Late Pleistocene to Holocene Ghayathi Formation in the United Arab Emirates provides a comprehensive numerical dataset that reveals the complex spatio‐temporal depositional and diagenetic evolution of a mixed siliciclastic–carbonate continental aeolianite. Fifty‐one thin sections and forty‐four rock samples of three sedimentary units (Madinat‐Zayed, Ghayathi and Fuwayrit formations) from the United Arab Emirates were analyzed for their grain‐size distribution, mineralogy and the bulk stable‐carbon and oxygen isotopic composition. Sorting, skewness and kurtosis of the grain‐size distributions provide evidence for a divergent aerodynamic behaviour between the carbonate and siliciclastic particles. The different grain‐size distributions between the inland and coastal sections of the Ghayathi Formation indicate that continental mixed clastic−carbonate aeolianites are affected by density‐driven selective transport and consequent traction sorting due to the nature of carbonate detritus. The transport decoupling of the different detrital components resulted in a ‘continental sorting’ effect, with the inland sections yielding layers characterized by a better sorted detritus than the coastal areas. All detritus originally composed of aragonite has been removed by dissolution during early meteoric diagenesis, with its shapes frequently preserved by micritic envelopes. The bulk stable‐isotope composition of the carbonate fraction reflects a decreasing degree of meteoric cementation from coastal to inland areas. The high complexity of the lateral and vertical distribution of the sedimentary, diagenetic and isotopic properties of continental mixed aeolianites, such as the Ghayathi Formation, highlights the problem of recognizing such deposits in the pre‐Quaternary sedimentary record.

Parkinson's disease, a neurodegenerative disease, is caused by dopaminergic neurons death and accompanied by rigidity, and postural instability, as well as bradykinesia. The cause of these neurons' death is still unclear. Since the dopaminergic neurons couldn't regenerate, therefore Parkinson's disease couldn't be cured. Thus, over the past decades, significant effort has been made to explore the etiology of Parkinson's disease development and ascertainment. This review aimed to highlight the progress that has been made in understanding Parkinson's disease pathophysiology. The role of oxidative stress, neuroinflammation, and apoptosis in the development of PD has been discussed. It has been noticed that oxidative stress, inflammation, and apoptosis are working together to develop Parkinson's disease, and each of these factors affects each other. Additionally, the experimental models and their drawbacks have been emphasized. Additionally, the mechanism of inducing Parkinson's disease (i.e., inducing neuroinflammation and oxidative stress) by neurotoxin has been highlighted.