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eLife ◽  
2021 ◽  
Vol 10 ◽  
Author(s):  
Jiedong Zhang ◽  
Yong Jiang ◽  
Yunjie Song ◽  
Peng Zhang ◽  
Sheng He

Regions sensitive to specific object categories as well as organized spatial patterns sensitive to different features have been found across the whole ventral temporal cortex (VTC). However, it is unclear that within each object category region, how specific feature representations are organized to support object identification. Would object features, such as object parts, be represented in fine-scale spatial tuning within object category-specific regions? Here, we used high-field 7T fMRI to examine the spatial tuning to different face parts within each face-selective region. Our results show consistent spatial tuning of face parts across individuals that within right posterior fusiform face area (pFFA) and right occipital face area (OFA), the posterior portion of each region was biased to eyes, while the anterior portion was biased to mouth and chin stimuli. Our results demonstrate that within the occipital and fusiform face processing regions, there exist systematic spatial tuning to different face parts that support further computation combining them.


Crustaceana ◽  
2021 ◽  
Vol 94 (11-12) ◽  
pp. 1359-1376
Author(s):  
Khadijeh Khalifi ◽  
Negin Salamat ◽  
Abdolali Movahedinia

Abstract There are differences between various crab species in the function and structure of organs involved in ionic and osmotic regulation processes. The antennal glands together constitute one of the most important organs involved in the osmoregulation in crabs. The present investigation aimed to study the tissue structure of the antennal glands and their Na+/K+-ATPase (NKA) pump activity in three true crab species from three different habitats, including the marine (Portunus pelagicus (Linnaeus, 1758)), the estuarine (Macrophthalmus dentipes Lucas in Guérin, 1836) and the freshwater habitat (Eriocheir hepuensis Dai, 1991). In this regard, the tissue structure of the antennal glands and the activity of the Na+/K+-ATPase (NKA) pump were assessed in these three selected species. The results showed that the antennal glands in all studied species consisted of two anterior parts and a posterior part. The anterior parts are composed of the proximal tubular region (PT) and the distal tubular region (DT). The PT and DT parts comprised the coelomosac and labyrinths in the anterior portion, and the bladder located in the posterior portion. However, despite the similarity in the general tissue structure of the antennal gland in marine, estuarine and freshwater crab species, some structural differences were observed between those species. Labyrinth cells, coelomosac podocytes, and bladder cells in the estuarine crab M. dentipes contained large vacuoles especially on the top (i.e., near the lumen) of the cells. The highest amount of NKA pump activity was measured in the antennal glands of M. dentipes (). The NKA pump plays a more important role in the estuary and seawater adaptation of crabs, but freshwater species are not highly dependent on the NKA enzyme for osmoregulation.


2021 ◽  
Vol 11 (11) ◽  
pp. 1539
Author(s):  
Gianluca Cruciani ◽  
Maddalena Boccia ◽  
Vittorio Lingiardi ◽  
Guido Giovanardi ◽  
Pietro Zingaretti ◽  
...  

Studies comparing organized (O) and unresolved/disorganized (UD) attachment have consistently shown structural and functional brain abnormalities, although whether and how attachment patterns may affect resting state functional connectivity (RSFC) is still little characterized. Here, we investigated RSFC of temporal and limbic regions of interest for UD attachment. Participants’ attachment was classified via the Adult Attachment Interview, and all participants underwent clinical assessment. Functional magnetic resonance imaging data were collected from 11 UD individuals and seven matched O participants during rest. A seed-to-voxel analysis was performed, including the anterior and the posterior cingulate cortex, the bilateral insula, amygdala and hippocampus as seed regions. No group differences in the clinical scales emerged. Compared to O, the UD group showed lower RSFC between the left amygdala and the left cerebellum (lobules VIII), and lower functional coupling between the right hippocampus and the posterior portion of the right middle temporal gyrus. Moreover, UD participants showed higher RSFC between the right amygdala and the anterior cingulate cortex. Our findings suggest RSFC alterations in regions associated with encoding of salient events, emotion processing, memories retrieval and self-referential processing in UD participants, highlighting the potential role of attachment experiences in shaping brain abnormalities also in non-clinical UD individuals.


Author(s):  
Karolina Brzegowy ◽  
Bernard Solewski ◽  
Paweł Brzegowy ◽  
Agata Musiał ◽  
Tadeusz Popiela ◽  
...  

Introduction : In acute ischemic stroke, collateral circulation determines tissue fate and treatment results. The aim of this study was to evaluate the role of anatomical variations of the Circle of Willis (CoW) in formation of cerebral collateral blood flow in patients with acute M1 occlusion. Methods : This study was a retrospective assessment of radiological examinations of patients with stroke due to middle cerebral artery M1 segment occlusion. All patients underwent mechanical thrombectomy from January 2015 until March 2021. The anatomy of the CoW was assessed on initial CT‐angiography and DSA. CTA was utilized to grade cranial collateral vasculature status and cortical vein opacification score (COVES). Non‐contrast CT scans and ASPECTS scores (using RAPID software) were used to determine the ischemic area. Results : A total of 100 patients were included in the analysis (58 females and 42 males, mean age: 71.6 +/‐ 13.9). We classified the anatomy of the CoW according to its continuity as a full circle. Patients with fully continuous CoW (n = 19) had worse COVES scores than those with CoW incomplete at both anterior and posterior portion (n = 9) (89% vs 68% with COVES 0–2, p = 0.179). No statistically significant results were found when comparing the enhancement of collaterals between these two groups (p = 0.390). The COVES scores were similar for patients with complete and incomplete anterior portions of CoW (77% vs 80% with COVES 0–2, p = 0.812). Patients with incomplete posterior portions of CoW had lower COVES scores than those with complete (80% vs 67% with COVES 0–2, p = 0.206). No statistically significant differences were discovered when comparing different types of the posterior communicating artery (adult, transitional and fetal). Analysis of ischemic areas determined as ASPECTS scores pre‐ and post‐thrombectomy yielded no significant differences between any of the groups. Conclusions : Although certain variants of the CoW have been reported to increase the risk of ischemic stroke, our results show that the anatomy of CoW has no large effect on collateral blood flow during acute M1 occlusion. We presume that the greater role is played by pial arterioles than anatomical variants of major cerebral arteries in cerebral collateral circulation formation. Detailed knowledge about the factors that influence collateral blood flow is crucial as it may aid in identification of patients prone to worse outcomes of ischemic stroke. Anatomical variants of CoW do not play a major role in formation of cerebral collaterals.


Author(s):  
Bernard Solewski ◽  
Karolina Brzegowy ◽  
Paweł Brzegowy ◽  
Agata Musiał ◽  
Tadeusz Popiela ◽  
...  

Introduction : This study aimed to determine what anatomical variants of the Circle of Willis (CoW) and the middle cerebral artery(MCA) are observed in patients with acute M1 occlusion and whether their prevalence differs from that described as “normal” in anatomy textbooks. Methods : We have performed a retrospective assessment of radiological examinations of patients with stroke due to middle cerebral artery M1 segment occlusion. All patients underwent mechanical thrombectomy from January 2015 until March 2021. The anatomy of the CoW was assessed on initial CT‐angiography and DSA. Branches of the MCA were observed on control DSA after recanalization. Results : A total of 100 patients were included in the analysis (58 females and 42 males, mean age: 71.6 +/‐ 13.9). Fully complete CoW was observed in 19% of patients. A total of 10% of patients had an incomplete anterior portion of CoW. In the incomplete anterior portion subgroup, the most common variation was the absence of anterior communicating artery (6% of total hemispheres), followed by the absence of one A1 (3% of total hemispheres). An incomplete posterior portion of CoW was identified in 79% of the patients. The absence of posterior communicating artery (PCoA) was observed in 59 patients. Sixteen patients had adult‐type PCoA, 3 patients had transitional‐type PCoA and 21 patients had fetal‐type posterior cerebral artery (PCA). In the subgroup of patients with fetal‐type posterior circle, 5 patients had no P1 segment of PCA. Anterior temporal branch of MCA was observed in 45% of the patients. Middle cerebral artery bifurcation was found in 80% of hemispheres, and trifurcation in 20%. In the bifurcation subgroup, 26% of MCAs had a dominating upper branch and 18% had a dominating lower branch. A duplicate MCA was observed in one hemisphere. Conclusions : In comparison to normal anatomy described in anatomy textbooks, the population of patients suffering from ischemic stroke due to M1 occlusion had a lower proportion of complete and closed CoW. A foetal type PCoA was observed to be prevalent (21%) in patients suffering from acute M1 occlusion. Detailed anatomical knowledge of anatomical variants of CoW in patients undergoing mechanical thrombectomy is essential for clinicians performing intravascular interventions and may aid procedure planning.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Chao-Min Huang ◽  
Man-Yee Chan ◽  
Jui-Ting Hsu ◽  
Kuo-Chih Su

Abstract Background Many types of titanium plates were used to treat subcondylar fracture clinically. However, the efficacy of fixation in different implant positions and lengths of the bone plate has not been thoroughly investigated. Therefore, the primary purpose of this study was to use finite element analysis (FEA) to analyze the biomechanical effects of subcondylar fracture fixation with miniplates at different positions and lengths so that clinicians were able to find a better strategy of fixation to improve the efficacy and outcome of treatment. Methods The CAD software was used to combine the mandible, miniplate, and screw to create seven different FEA computer models. These models with subcondylar fracture were fixed with miniplates at different positions and of different lengths. The right unilateral molar clench occlusal mode was applied. The observational indicators were the reaction force at the temporomandibular joint, von Mises stress of the mandibular bone, miniplate and screw, and the sliding distance on the oblique surface of the fracture site at the mandibular condyle. Results The results showed the efficacy of fixation was better when two miniplates were used comparing to only one miniplates. Moreover, using longer miniplates for fixation had better results than the short one. Furthermore, fixing miniplates at the posterior portion of subcondylar region would have a better fixation efficacy and less sliding distance (5.46–5.76 μm) than fixing at the anterolateral surface of subcondylar region (6.10–7.00 μm). Conclusion Miniplate fixation, which was placed closer to the posterior margin, could effectively reduce the amount of sliding distance in the fracture site, thereby achieving greater stability. Furthermore, fixation efficiency was improved when an additional miniplate was placed at the anterior margin. Our study suggested that the placement of miniplates at the posterior surface and the additional plate could effectively improve stability.


2021 ◽  
pp. 2783-2789

Diabetes Mellitus causes diabetic retinopathy (DR). It can cause blindness if not diagnosed early. Disease diagnosis is an essential and highly scrutinized biomedical field in which machine learning has been significantly used. Recently, machine learning has emerged as one of the most widely used approaches for improving performance in various areas, including medical image analysis and classification. This research compares several machine learning experiments based on the accuracy and sensitivity of retinal fundus pictures acquired by the fundus camera to assess several strategies for identifying Diabetic retinopathy. Inflammatory illnesses in the posterior portion of fundus photography are followed by retinal imaging. In particular, machine learning and deep learning are cutting-edge technologies well-suited for data analytics applications in the medical field. The results were compared to those of other approaches such as deep neural networks and other best practices. This work will be beneficial to researchers who want to apply their research in this field. During this research, we have gone through several research papers. This paper includes findings from other researcher’s studies, which have been summarized to present their pros and cons for disease diagnosis


2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Mi Young Kim ◽  
Young Jin Suh ◽  
Yeong Yi An

Abstract Background To evaluate the usefulness of surveillance-abbreviated magnetic resonance imaging (AB-MRI) for the detection of ipsilateral local tumor recurrence (LTR) in patients who underwent oncoplastic breast-conserving surgery (BCS) with acellular dermal matrix (ADM) by comparing its diagnostic performance with that of mammography (MG) and ultrasonography (US). Methods The postoperative MG, US, and AB-MRI findings of the ipsilateral breast and pathological results of 324 patients who underwent oncoplastic BCS using ADM were reviewed. The cancer detection rate (CDR), sensitivity, specificity, positive predictive value (PPV) for biopsy, accuracy, and area under the curve (AUC) for each imaging modality were calculated. Results A total of 8 ipsilateral LTRs were diagnosed, and most cancers (87.5%) were stage 0 or 1 (median size of invasive cancer, 1.44 cm; range, 0.7–2 cm). The CDRs of MG, US, MG + US, and AB-MRI were 0.009, 0.012, 0.015, and 0.025 per woman, respectively. Three cancers were detectable on only AB-MRI, and the additional CDR of AB-MRI was 0.010. The sensitivity and specificity of MG, US, MG + US, and AB-MRI were 37.5%, 50%, 62.5%, and 100% and 99.7%, 98.4%, 98.1%, and 97.8%, respectively. The PPVs for biopsy were 75%, 44.4%, 45.5%, and 53.3%, respectively. The AUC was significantly higher for AB-MRI (0.989) than for MG alone (0.686, P = 0.0009), US alone (0.742, P = 0.009), and MG + US (0.803, P = 0.04). A total of 66.7% of cancers visible on only AB-MRI were located at the deep posterior portion of the excision cavity, which might have been missed with MG or MG + US due to masking by the ADM filler. Conclusion AB-MRI can improve the detection of ipsilateral LTR despite postoperative changes caused by ADM fillers compared to conventional MG and US. Patients who undergo BCS with ADM can be candidates for AB-MRI surveillance considering improved cancer detection and high sensitivity.


2021 ◽  
pp. 1-11
Author(s):  
Haruo Kanno ◽  
Toshimi Aizawa ◽  
Ko Hashimoto ◽  
Eiji Itoi ◽  
Hiroshi Ozawa

OBJECTIVE Various surgical procedures are used to manage thoracic myelopathy due to ossification of the posterior longitudinal ligament (OPLL). However, the outcomes of surgery for thoracic OPLL are generally unfavorable in comparison to surgery for cervical OPLL. Previous studies have shown a significant risk of perioperative complications in surgery for thoracic OPLL. Thus, a safe and secure surgical method to ensure better neurological recovery with less perioperative complications is needed. The authors report a novel concept of anterior decompression through a posterior approach aimed at anterior shift of the OPLL during surgery rather than extirpation or size reduction of the OPLL. This surgical technique can securely achieve anterior shift of the OPLL using a curved drill, threadwire saw, and curved rongeur. The preliminary outcomes were investigated to evaluate the safety and efficacy of this technique. METHODS This study included 10 consecutive patients who underwent surgery for thoracic OPLL. Surgical outcomes, including the ambulatory status, Japanese Orthopaedic Association (JOA) score, and perioperative complications, were investigated retrospectively. In this surgery, pedicle screws are introduced at least three levels above and below the corresponding levels. The laminae, facet joints, transverse processes, and pedicles are then removed bilaterally at levels wherein subsequent anterior decompression is performed. For anterior decompression, the OPLL and posterior portion of the vertebral bodies are partially resected using a high-speed drill with a curved burr, enabling the removal of osseous tissues just ventral to the spinal cord without retracting the dural sac. To securely shift the OPLL anteriorly, the intact PLL and posterior portion of the vertebral bodies cranial and caudal to the lesion are completely resected using a threadwire saw and/or curved rongeur. Rods are connected to the screws, and bone grafting is performed for posterolateral fusion. RESULTS Five patients were nonambulatory before surgery, but all were able to walk at the final follow-up. The average JOA score before surgery and at the final follow-up was 3.2 and 8.8 points, respectively. Notably, the mean recovery rate of JOA score was 72%. Furthermore, no patients showed neurological deterioration postoperatively. CONCLUSIONS The surgical technique is a useful alternative for safely achieving sufficient anterior decompression through a posterior approach and may consequently reduce the risk of postoperative neurological deterioration and improve surgical outcomes in patients with thoracic OPLL.


2021 ◽  
pp. 149-151
Author(s):  
Ravi Khade ◽  
Amol Thosar ◽  
Sachin Tayade

The present investigation deals with the systematic observation of a new species of Phyllodistomum khadensis Sp. Nov. from fresh water fish Wallago attu. The worm is close to all species of genus phyllodistomum in general the body is narrow while the posterior portion of the body is broad and triangular in shape. The oral sucker is terminal. The ventral sucker is rounded in structure and larger than oral sucker. The bladder is long and tubular.The anterior testis is smaller than posterior one. Vas deferans is long, tubular and forms vasa efferentia. Female reproductive organ includes single ovary having its duct. The vitelline glands are two in number compact lobes on either side of the ootype. The eggs are oval to round in shape.


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