In the context of growing evidence supporting disturbed neural connectivity in the pathogenesis of depressive symptoms, we used the diffusion tensor imaging technique to investigate white matter disruptions in previously undiagnosed and hence treatment-naive young adults with mild and moderate depressive symptoms screened by Beck's Depression Inventory test compared with age-matched and sex-matched healthy controls. This is the first diffusion tensor imaging study to assess minor forms of depression. We hypothesized that subthreshold depressive symptoms share the same neural disruptions as major depressive disorder (MDD). Each group included 47 participants with a mean age of 20.1±1.1 years. The exploratory region of interest method was used to assess integrity (fractional anisotropy and mean diffusivity) in 48 regions of the brain based on Mori atlas. Data were recruited from the Southwest University Longitudinal Imaging Multimodal Brain Data Repository. The following pathways showed significant microstructural changes by means of reduced fractional anisotropy in the group with depressive symptoms compared with normal participants: pontine crossing tract; genu of the corpus callosum; posterior limb of the internal capsule (bilaterally); and anterior, posterior, and superior corona radiata (bilaterally). None of the above regions, but the middle cerebellar peduncle and the right superior fronto-occipital fasciculus were shown to differ significantly in the mean diffusivity values between the two groups. On the basis of the current results, our findings provide evidence that the white matter impairments in the interhemispheric connections and frontal-subcortical neural circuits may play a key role in the pathogenesis of depression in young adults. The similarity of neural underpinnings in MDD and minor depressive disorder in this study further proves that these two mood disorders exist in a continuum, and milder depressive symptoms can herald a major episode. Besides the high prevalence and great burden of subthreshold forms of depression on personal and social aspects of life, there is lack of knowledge of them and most studies have mainly focused on MDD. This study provides a new avenue in addressing neuropathology of depression, mainly in subtle forms that are almost always overlooked.

Depression is a significant disabling feature in Parkinson's disease (PD). However, the neuropathology of this comorbidity is still unclear. In fact, few studies have tried to elucidate the neural correlates of depression in PD and have mostly examined specific regions of interest. In this study, we applied diffusion MRI connectometry, a powerful complementary approach to investigate alterations in whole white matter pathways regarding the severity of depressive symptoms. Using a multiple regression model, the correlation of severity of depressive symptoms assessed by the Hospital Anxiety and Depression Scale (HADS) with white matter connectivity was surveyed in 27 non-demented PD patients related to 26 age, sex, and educational level-matched healthy subjects. Results revealed areas, where white matter quantitative anisotropy (QA) was correlated with depression score in PD patients, without any significant association in healthy controls. The analysis showed a significant negative association (false discovery rate < 0.05) between scores on depression subscale of HADS in PD patients and QA of left Cingulum, Genu, and Splenium of the Corpus Callosum, and anterior and posterior limbs of the right internal capsule. This finding might improve our understanding of the neural basis of depression and its severity in PD.

Introduction: Acute-type aortic dissection (AD) during pregnancy is considered a rare and potentially fatal complication for both mother and fetus. Although the definite treatment for an acute-type AD is considered to be open-heart surgery, the decision to perform such a surgery during pregnancy requires a multidisciplinary approach and carries significant risks.Methods: In the present review of the literature, we have discussed various challenges in the management of acute-type AD during pregnancy, including therapeutic approaches, choosing the preferred imaging modalities, surgical techniques, and medication challenges. We have also reported an 8-week pregnant woman with Marfan syndrome who presented with chest pain and was diagnosed with acute AD. Results:The patient underwent a Bentall operation and was discharged in good condition with her fetus alive. The medical team's various decisions during preoperative, operative, and postoperative treatments were discussed.Conclusions: Type A AD is considered infrequent in the second and third trimester of pregnancy and rare in the first trimester. Performing a CMR study without contrast in stable patients can help evaluate the extension of the flap. Urgent surgery in the hands of a skilled surgeon may prove lifesaving for the mother while maximizing the likelihood of preserving the fetus.

Distal humerus fractures commonly occur in adults with low bone mineral density causing major technical challenges for orthopedic surgeons. Persian fixation method was introduced as a novel technique to stabilize small fragments in comminuted distal humerus fractures using a set of K-wires and a reconstruction plate. The present study aims to measure this technique's stiffness and stability of this technique and analyze the effect of influential parameters with numerical simulation and biomechanical testing on a cadaveric specimen. Validation of the finite element (FE) model was conducted based on results of experiments. The results indicated that Delta configuration mainly led to a higher stiffness in the case of axial loading and anterior bending compared to L configuration. Analyzing the influential factors of this technique suggests that changes in diameter and number of K-wires have a similarly significant effect on the construct stiffness while the height of plate had a slight influence. Also, the diameter of wires was the most effective parameter for implant failure, particularly in the 3-pin construct, which caused a reduction in failure risk by about 60%. The results revealed that the Persian fixation method would achieve suitable stability compared to the dual-plating technique.

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