Anatomical Structures Research Articles

Visualization of nonsmall-cell lung cancer by near-infrared fluorescence imaging with tumor-targeting peptide ABT-510

Nonsmall-cell lung cancer (NSCLC) is the most frequent type of lung cancer, with early surgical treatment proving vital for prolonged patient survival. However, precise visualization of NSCLC remains a challenge due to limited molecular imaging probes, the unique anatomical structure of the lungs, and respiratory movement interference. In this study, we investigated the potential utility of CD36, which is highly expressed in NSCLC, as an imaging target. A selective and water-soluble fluorescent probe, MPA–ABT-510, was successfully constructed by coupling ABT-510 with MPA, a near-infrared (NIR) fluorescent dye. Molecular docking analysis shows that MPA–ABT-510 possesses strong binding affinity to the CD36 protein, with specific hydrogen bond interactions at defined amino acid residues. In vitro assays reveals that the fluorescein isothiocyanate-labeled peptide ABT-510 specifically binds to the CD36-high expressing NSCLC cell lines H1299 and A549. In vivo imaging verifies that the MPA–ABT-510 efficiently accumulates in the tumor site with a distinct fluorescent signal. Ex vivo imaging revealed that tumor-to-lung fluorescence ratios for subcutaneous and orthotopic H1299 mouse models were 7.19 ± 0.73 and 1.91 ± 0.42, respectively, while those for A549 mice were 5.53 ± 0.64 and 1.77 ± 0.41, respectively. Biodistribution analysis demonstrated efficient MPA–ABT-510 uptake in H1299 and A549 liver metastases models with tumor-to-liver fluorescence ratios of 2.47 ± 0.48 and 2.19 ± 0.22, respectively. High MPA–ABT-510 accumulation was evident in A549 intestinal metastases models, as evidenced by tumor-to-colorectal fluorescence ratios of 4.27 ± 0.11. MPA–ABT-510 exhibits superior imaging capabilities with minimal safety concerns, so it is a promising candidate for NSCLC surgical navigation.

Real-time detection and resection of sentinel lymph node metastasis in breast cancer through a rare earth nanoprobe based NIR-IIb fluorescence imaging

Sentinel lymph node (SLN) biopsy is a commonly employed procedure for the routine assessment of axillary involvement in patients with breast cancer. Nevertheless, conventional SLN mapping cannot reliably distinguish the presence and absence of metastatic disease. Additionally, the complex anatomical structures and lymphatic drainage patterns surrounding tumor sites pose challenges to the sensitivity of the near-infrared fluorescence imaging with subcutaneously injected probes. To identifying the SLN metastases, we developed a novel nanoprobe for in vivo fluorescence imaging within the second near-infrared (NIR-II) range. This nanoprobe utilizes rare-earth nanoparticles (RENPs) to emit bright fluorescence at 1525 nm and is conjugated with tumor-targeted hyaluronic acid (HA) to facilitate the detection of metastatic SLN. Upon intravenous administration, RENPs@HA effectively migrated to SLNs and selectively entered metastatic breast tumor cells through CD44-mediated endocytosis. The RENPs@HA nanoprobes exhibited rapid accumulation in metastatic inguinal lymph nodes in mouse model, displaying a 5.8-fold-stronger fluorescence intensity to that observed in normal SLNs. Consequently, these nanoprobes effectively differentiate metastatic SLNs from normal SLNs. Importantly, the probes accurately detected micrometastases. These findings underscore the potential of RENPs@HA for real-time visualization and screening of SLNs metastasis.

Comparative Effects of Water Scarcity on the Growth and Development of Two Common Bean (Phaseolus vulgaris L.) Genotypes with Different Geographic Origin (Mesoamerica/Andean)

Drought stress is widely recognized as a highly detrimental abiotic stress factor that significantly impacts crop growth, development, and agricultural productivity. In response to external stimuli, plants activate various mechanisms to enhance their resistance or tolerance to abiotic stress. The common bean, a most important legume according to the FAO, serves as a staple food for millions of people worldwide, due to its rich protein, carbohydrate, and fiber content, concurrently, and water scarcity is the main factor limiting common bean production. The process of domestication and on-farm conservation has facilitated the development of genotypes with varying degrees of drought stress resistance. Consequently, using landraces as biological material in research can lead to the identification of variants with superior resistance qualities to abiotic stress factors, which can be effectively integrated into breeding programs. The central scope of this research was to find out if different geographic origins of common bean genotypes can determine distinct responses at various levels. Hence, several analyses were carried out to investigate responses to water scarcity in three common bean genotypes, M-2087 (from the Mesoamerican gene pool), A-1988 (from the Andean gene pool) and Lechinta, known for its high drought stress resistance. Plants were subjected to different water regimes, followed by optical assessment of the anatomical structure of the hypocotyl and epicotyl in each group; furthermore, the morphological, physiological, and biochemical parameters and molecular data (quantification of the relative expression of the thirteen genes) were assessed. The three experimental variants displayed distinct responses when subjected to 12 days of water stress. In general, the Lechinta genotype demonstrated the highest adaptability and drought resistance. The M-2087 landrace, originating from the Mesoamerican geographic basin, showed a lower resistance to water stress, compared to the A-1988 landrace, from the Andean basin. The achieved results can be used to scale up future research about the drought resistance of plants, analyzing more common bean landraces with distinct geographic origins (Mesoamerican/Andean), which can then be used in breeding programs.

Dependent contrast layering sign on CT in patients irrespective of cardiac dysfunction and its clinical implications: A preliminary retrospective study

Purpose: CT findings of contrast layering in dependent areas of the central venous system and solid organs have been reported in the literature to be associated with imminent cardiac arrest. However, no systematic research has explored the association of this distinctive CT finding with cardiac arrest and mortality. Therefore, we investigated the radiological manifestations of dependent layering of contrast in various vascular structures and organs and its clinical implications. Methods: A computerized search of radiological database was conducted using keywords “layering contrast” between January 2008 and January 2022. After reviewing CT scans of 226 patients that met the keyword criteria, 21 patients who exhibited the dependent contrast layering sign (DCLS) in vascular structures and organs were included in the final study population. Clinical data such as cardiac arrest within 2 hours, in-hospital mortality, and shock index ≥ 0.9 were collected. Number of involved structures in each patient is also investigated. Statistical significance and frequency regarding the association between radiologic findings and clinical data were analyzed. Results: The distribution of DCLS across anatomical structures reveals IVC is involved in 90.5% of patients and followed by hepatic vein (80.9%), liver parenchyma and right atrium. Cardiac arrest within 2 hours is significantly more common in patients with DCLS in right atrium (p=0.02, odds ratio = 21.6) and liver parenchyma (p=0.01, odds ratio = 24.8). DCLS in liver parenchyma is associated with the highest rate of in-hospital mortality (4 of 7, 57.1%). The total number of involved structures (p=0.01) and the number of common structures (p=0.001) are significantly higher in patients with cardiac arrest within 2 hours. Conclusions: The presence of DCLS in the right atrium and liver, as well as the larger number of involved structures, are significantly associated with impending cardiac arrest. Thus, it may offer additional insights for both radiologists and clinicians and aid in prompt initiation of resuscitative interventions before the onset of cardiac arrest. Nevertheless, larger prospective studies are warranted to validate the clinical relevance of DCLS across various vascular structures and organs.

Image Quality Assessment of a Deep Learning-Based Automatic Bone Removal Algorithm for Cervical CTA.

The present study aims to evaluate the postprocessing image quality of a deep-learning (DL)-based automatic bone removal algorithm in the real clinical practice for cervical computed tomography angiography (CTA). A total of 100 patients (31 females, 61.4 ± 12.4 years old) who had performed cervical CTA from January 2022 to July 2022 were included retrospectively. Three different types of scanners were used. Ipsilateral cervical artery was divided into 10 segments. The performance of the DL algorithm and conventional algorithm in terms of bone removal and vascular integrity was independently evaluated by two radiologists for each segment. The difference in the performance between the two algorithms was compared. Inter- and intrarater consistency were assessed, and the correlation between the degree of carotid artery stenosis and the rank of bone removal and vascular integrity was analyzed. Significant differences were observed in the rankings of bone removal and vascular integrity between the two algorithms on most segments on both sides. Compared to DL algorithm, the conventional algorithm showed a higher correlation between the degree of carotid artery stenosis and vascular integrity (r = -0.264 vs r = -0.180). The inter- and intrarater consistency of DL algorithm were found to be higher than or equal to those of conventional algorithm. The DL algorithm for bone removal in cervical CTA demonstrated significantly better performance than conventional postprocessing method, particularly in the segments with complex anatomical structures and adjacent to bone.

Retrospective epidemiological study over 8‐year period on zygomatic complex fractures: A single centre experience

AbstractObjectivesThe purpose of this study was to do a retrospective analysis of patients with zygomatic fractures who were treated at the Department of Maxillofacial Surgery, Regional University Hospital of Perugia, Italy, between 2016 and 2023.Materials and MethodsPatients were evaluated based on various parameters including age, sex, aetiology, symptoms, comorbidity, clinical findings, zygomatic fracture type, other facial fractures, treatment, waiting time before the operation, complications and sequelae. In the period described, we had 123 cases of zygomatic fractures requiring surgical intervention.ResultsAmong the patients, 101 were male (82.1%) and 22 were female (17.9%). The average age of the patients was 48.65 years (ranging from 7 to 94 years).The leading cause of these fractures was sports‐related injury (n = 32; 26.01%), and isolated zygomatic bone fractures were the most frequent (72.43%). The most common clinical signs and symptoms were pain, depression of the facial profile, difficulty in chewing, limitation of the buccal opening, difficulty in protrusion movements and mandibular lateralization. Ninety‐six per cent of patients underwent surgery under general anaesthesia, with open reduction and internal fixation.ConclusionsThe successful and effective management of zygomatic fractures requires a solid understanding of its anatomy, pathophysiology and related biomechanical structures and forces. The continuous research in epidemiology, aetiology, materials and techniques will further refine our treatments which are nowadays more and more customized according to the type of trauma.

Landmark-based auto-contouring of clinical target volumes for radiotherapy of nasopharyngeal cancer.

The delineation of clinical target volumes (CTVs) for radiotherapy for nasopharyngeal cancer is complex and varies based on the location and extent of disease. The current study aimed to develop an auto-contouring solution following one protocol guidelines (NRG-HN001) that can be adjusted to meet other guidelines, such as RTOG-0225 and the 2018 International guidelines. The study used 2-channel 3-dimensional U-Net and nnU-Net framework to auto-contour 27 normal structures in the head and neck (H&N) region that are used to define CTVs in the protocol. To define the CTV-Expansion (CTV1 and CTV2) and CTV-Overall (the outer envelope of all the CTV contours), we used adjustable morphological geometric landmarks and mimicked physician interpretation of the protocol rules by partially or fully including select anatomic structures. The results were evaluated quantitatively using the dice similarity coefficient (DSC) and mean surface distance (MSD) and qualitatively by independent reviews by two H&N radiation oncologists. The auto-contouring tool showed high accuracy for nasopharyngeal CTVs. Comparison between auto-contours and clinical contours for 19 patients with cancers of various stages showed a DSC of 0.94±0.02 and MSD of 0.4±0.4mm for CTV-Expansion and a DSC of 0.83±0.02 and MSD of 2.4±0.5mm for CTV-Overall. Upon independent review, two H&N physicians found the auto-contours to be usable without edits in 85% and 75% of cases. In 15% of cases, minor edits were required by both physicians. Thus, one physician rated 100% of the auto-contours as usable (use as is, or after minor edits), while the other physician rated 90% as usable. The second physician required major edits in 10% of cases. The study demonstrates the ability of an auto-contouring tool to reliably delineate nasopharyngeal CTVs based on protocol guidelines. The tool was found to be clinically acceptable by two H&N radiation oncology physicians in at least 90% of the cases.

Augmented reality and optical navigation assisted orbital surgery: a novel integrated workflow

Abstract Objectives Due to the close topographical relationship of functional relevant anatomic structures, limited space and cosmetic aspects orbital surgery will remain a challenging discipline. Therefore, novel technical capabilities are necessary for further surgical progress. We here tested the integration of augmented reality and optical navigation in one workflow for interdisciplinary decision-making, feasibility and intraoperative guidance. Methods High-resolution contrast-enhanced MRI and CT scans were automated and manual-assisted segmented to achieve a detailed three-dimensional (3D) model of the individual patho-anatomical relationships. Augmented reality was used for interdisciplinary preoperative planning and intraoperative intuitive navigation. Mayfield clamp head holder in combination with optical surface matching registration assured navigation assisted microsurgery. Results Combinations of different MRI-sequences and CT-scans were necessary for detailed 3D-modeling. Modeling was time consuming and only viable in the hands of medical, surgical and anatomical trained staff. Augmented reality assured a quick, intuitive interdisciplinary orientation. Intraoperative surface matching registration enabled precise navigation in the orbital space. Conclusions Optical Navigation and microscope integration achieved a straightforward microsurgical workflow and should be implemented regularly. Augmented reality represented a useful tool for preoperative interdisciplinary planning and intraoperative intuitive orientation. It further stated an excellent educational tool.

An artificial intelligence-based nerve recognition model is useful as surgical support technology and as an educational tool in laparoscopic and robot-assisted rectal cancer surgery.

Artificial intelligence (AI) has the potential to enhance surgical practice by predicting anatomical structures within the surgical field, thereby supporting surgeons' experiences and cognitive skills. Preserving and utilising nerves as critical guiding structures is paramount in rectal cancer surgery. Hence, we developed a deep learning model based on U-Net to automatically segment nerves. The model performance was evaluated using 60 randomly selected frames, and the Dice and Intersection over Union (IoU) scores were quantitatively assessed by comparing them with ground truth data. Additionally, a questionnaire was administered to five colorectal surgeons to gauge the extent of underdetection, overdetection, and the practical utility of the model in rectal cancer surgery. Furthermore, we conducted an educational assessment of non-colorectal surgeons, trainees, physicians, and medical students. We evaluated their ability to recognise nerves in mesorectal dissection scenes, scored them on a 12-point scale, and examined the score changes before and after exposure to the AI analysis videos. The mean Dice and IoU scores for the 60 test frames were 0.442 (range 0.0465-0.639) and 0.292 (range 0.0238-0.469), respectively. The colorectal surgeons revealed an under-detection score of 0.80 (± 0.47), an over-detection score of 0.58 (± 0.41), and a usefulness evaluation score of 3.38 (± 0.43). The nerve recognition scores of non-colorectal surgeons, rotating residents, and medical students significantly improved by simply watching the AI nerve recognition videos for 1min. Notably, medical students showed a more substantial increase in nerve recognition scores when exposed to AI nerve analysis videos than when exposed to traditional lectures on nerves. In laparoscopic and robot-assisted rectal cancer surgeries, the AI-based nerve recognition model achieved satisfactory recognition levels for expert surgeons and demonstrated effectiveness in educating junior surgeons and medical students on nerve recognition.

Fruiting Characteristics and Molecular-Assisted Identification of Korla Fragrant Pear Bud Mutation Materials

Korla fragrant pear is a high-quality local pear variety native to Xinjiang, China. Currently, the low fruit-setting rate and low calyx shedding rate problems in Korla fragrant pears have been highlighted, which seriously affect the fruit yield and quality. It is of great significance to research the fruiting characteristics and molecular-assisted identification of Korla fragrant pear bud mutation materials for enriching the germplasm resources of Korla fragrant pear. In this research, a natural pollination group (YB) of Korla fragrant pear bud mutation materials and a natural pollination group (CK) of Korla fragrant pears were established. On the fruiting characteristics, the fruit-setting rate and calyx-removal rate of the two groups were investigated. In terms of fruit quality, the fruit shape index, fruit specific gravity, soluble solids content, sugar:acid ratio, soluble sugar content, and other indicators were measured. For the anatomical structure of the calyx tube, the detachment cells were observed. The formation time of the two groups of detached cells was compared. In the GBS simplified genome sequencing, a phylogenetic tree was constructed based on the obtained SNP sites. A principal component analysis, population genetic structure analysis, and genetic diversity index analysis were carried out. In the aspect of SSR molecular marker identification, the SSR types were counted. Polyacrylamide gel electrophoresis was performed. The results demonstrate the following: (1) the fruit-setting rate (30.87%) and calyx-removal rate (68.11%) in the YB group were significantly higher than those in the CK group (19.37%) and the calyx-removal rate (55.18%). (2) There was no significant difference in fruit quality indexes, such as average fruit weight (127.10–130.00 g) and soluble sugar content (9.47–9.56%) between the two groups. (3) Abscission-layer cells were observed at 2, 4, 6, 8, and 10 h after calyx tube discoloration in the YB group and at 48, 72, and 96 h after calyx tube discoloration in the CK group. (4) The genetic background of the YB group and the CK group was similar at the GBS level, but there were differences at the DNA level. This research finally shows that Korla fragrant pear bud mutation material is a good germplasm resource. This germplasm resource can promote the structural optimization of Korla fragrant pear varieties and the healthy development of the industry.

Mechanical design and kinematic performance of an anthropomorphic shoulder rehabilitation exoskeleton

Shoulder rehabilitation exoskeleton is a mechanical device to assist stroke patients in rehabilitation training, remodeling patients' neurological function by strengthening the muscles and promoting the recovery of shoulder function. At present, there are problems such as insufficient degree of freedom (DOF), insufficient overall range of motion (ROM), presence of passive joints, lack of the support of scapulohumeral rhythm (SHR), and poor kinematic synergy with the shoulder. This paper designs a 5-DOF shoulder rehabilitation exoskeleton based on the anatomical structure of the human shoulder and its motion characteristics, takes the 2-DOF shoulder girdle mechanism and the 3-DOF ball and socket mechanism as the main body taking into account the ergonomic factors in design, which ensures the synergistic motion with the patient's shoulder and provides the patient with a wide ROM. After setting up the drive and control system, this paper completes the prototype of the exoskeleton, furthermore, this paper describes the range of motion and kinematic synergy test. ROM tests and kinematic synergy experiments are conducted to evaluate the kinematic performance of this shoulder exoskeleton. The experimental results indicate that the shoulder exoskeleton prototype offers a high level of kinematic synergy with the wearer throughout a broad ROM.

UPAMAN PRAMANA W.S.R. TO TUNNASEVANI SANDHI

Background: -Fundamental aspects of Ayurved concern with Sandhi sharir. It gives information about the basic structure of the human body, which is essential in diagnosis and treatment. Acharya Charak describes sandhi as “Ashthi sanyoga sthanam”, i.e meeting place between two or more bones (Asthi) is called sandhi1 . Acharya Sushruta had categorised sandhi sharira into two main types: Chala (movable) & Achala sandhi (immovable or fixed)2 . Sutures present between the skull bones are immovable joints. Upamana pramana (analogy) is one of the types of pramana widely utilised to explain Sharir concepts. Upamana pramana enlightens the features of unmanifested things with a familiar or manifested thing based on similarities. These analogies mentioned in ancient texts are found to be very helpful in understanding the basic concepts of Rachana Sharir, like Paribhasha, Garbha sharir, Sandhi sharir, Marma sharir etc. The anatomical concept of ‘Tunnasevani Sandhi’ is one example of using analogy. So, a sincere effort has been made to evaluate and analyse the anatomical concept of Tunnasevani sandhi with the help of Upaman Praman. Materials & Methods: The study for Upamana pramana related to Tunnasevani sandhi is done with the help of both Ayurvedic and Modern texts. From Brihatrayis and Laghutrayis and other classical books. Results: It is concluded that Tunnasevani sandhi is located in the skull, & the predominant anatomical structures present in the cranial vault are three sutures- sagittal, parietal & lambdoid suture.

Molecular developments in parasellar tumors and potential therapeutic implications.

The parasellar region is the anatomical area around the sella turcica that represents a crucial crossroad for important adjacent structures. Several distinct tumors can primarily originate from this area, the most common being meningiomas, gliomas, embryonal cell tumors, germ cell tumors and craniopharyngiomas. In addition, a number of systemic and inflammatory disorders can also affect the parasellar region most commonly involving the pituitary. These lesions have different pathology characteristics and malignant potential according to the new WHO CNS5 2021 classification. Signs and symptoms may be non-specific and are mostly related to a mass effect on the surrounding anatomical structures and/or impairment of endocrine function whereas the vast majority lack a secretory component. The mutational signature analysis based on advances in molecular techniques, has recently enabled the identification of specific gene mutations or signalling pathway aberrations. These developments may serve as a powerful mean to delineate the pathophysiology of these lesions and serve as a diagnostic, prognostic and therapeutic tool, particularly for high-risk populations. Treatment options include surgery alone or in combination with radiotherapy, chemotherapy and disease-specific medical therapy in order to prevent recurrence or further tumor growth along with replacement of coexistent pituitary hormonal deficiencies. In this comprehensive review, we present current state-of-the-art developments in the histopathology and molecular biology of these lesions that may be utilized by a dedicated multidisciplinary team of relevant specialties for the diagnosis, monitoring and treatment of the parasellar lesions that often represent a diagnostic and therapeutic challenge.

Temporal Changes on Postgadolinium MR Vessel Wall Imaging Captures Enhancement Kinetics of Intracranial Atherosclerotic Plaques and Aneurysms.

Analysis of vessel wall contrast kinetics (ie, wash-in/washout) is a promising method for the diagnosis and risk-stratification of intracranial atherosclerotic disease plaque (ICAD-P) and the intracranial aneurysm walls (IA-W). We used black-blood MR imaging or MR vessel wall imaging to evaluate the temporal relationship of gadolinium contrast uptake kinetics in ICAD-Ps and IA-Ws compared with normal anatomic reference structures. Patients with ICAD-Ps or IAs who underwent MR vessel wall imaging with precontrast, early postcontrast (5-15 minutes), and delayed postcontrast (20-30 minutes) 3D T1-weighted TSE sequences were retrospectively studied. ROIs of a standardized diameter (2 mm) were used to measure the signal intensities of the cavernous sinus, pituitary infundibulum, temporalis muscle, and choroid plexus. Point ROIs were used for ICAD-Ps and IA-Ws. All ROI signal intensities were normalized to white matter signal intensity obtained using ROIs of 10-mm diameter. Measurements were acquired on precontrast, early postcontrast, and delayed postcontrast 3D T1 TSE sequences for each patient. Ten patients with 17 symptomatic ICAD-Ps and 30 patients with 34 IA-Ws were included and demonstrated persisting contrast uptake (P < .001) of 7.21% and 10.54% beyond the early phase (5-15 minutes postcontrast) and in the delayed phase (20-30 minutes postcontrast) on postcontrast MR vessel wall imaging. However, normal anatomic reference structures including the pituitary infundibulum and cavernous sinus demonstrated a paradoxical contrast washout in the delayed phase. In both ICAD-Ps and IA-Ws, the greatest percentage of quantitative enhancement (>70%-90%) occurred in the early phase of postcontrast imaging, consistent with the rapid contrast uptake kinetics of neurovascular pathology. Using standard MR vessel wall imaging techniques, our results demonstrate the effects of gadolinium contrast uptake kinetics in ICAD-Ps and IA-Ws with extended accumulating enhancement into the delayed phase (> 15 minutes) as opposed to normal anatomic reference structures that conversely exhibit decreasing enhancement. Because these relative differences are used to assess qualitative patterns of ICAD-P and IA-W enhancement, our findings highlight the importance of standardizing acquisition time points and MR vessel wall imaging protocols to interpret pathologic enhancement for the risk stratification of cerebrovascular pathologies.

Which patients need anterior cruciate ligament reconstruction after initial treatment with rehabilitation? A scoping review.

Some patients with anterior cruciate ligament (ACL) injury initially treated with rehabilitation need ACL reconstruction (ACLR); yet, it is unclear what characterizes these patients. This review aimed to describe predictors for ACLR in patients initially treated with rehabilitation. A systematic literature search was performed in the Cochrane, Embase, Medline, SportsDiscus and Web of Science databases from inception to 21 February 2023. Articles describing characteristics in adult patients with ACL injury undergoing ACLR after a minimum of 5 weeks rehabilitation were included. It was a priori chosen that characteristics described in at least three articles were considered more certain and could be defined as a predictor for ACLR, and those described in less than three articles were considered less certain and therefore defined as possible predictors. Articles were screened by two independent reviewers. The study was originally intended as a systematic review with meta-analysis, but in case of limited data, we would convert it to a scoping review, as was the case for this review. There were 22,836 studies identified, and 181 full texts were screened, of which 10 papers were finally included. Only lower age and higher preinjury activity level were identified as predictors for ACLR. Another 12 possible predictors were identified in single studies. Through an iterative process, potential predictors were categorized into four groups: patient demographics, knee function, patient-reported outcome measures and anatomical structures. Lower age and higher preinjury activity level were the only predictors for ACLR after initial treatment with rehabilitation. While younger and highly active patients show a higher need for ACLR, more studies focussing on predictors and reasons for delayed ACLR are warranted. Level II.

DRRN: Differential rectification &amp; refinement network for ischemic infarct segmentation

AbstractAccurate segmentation of infarct tissue in ischemic stroke is essential to determine the extent of injury and assess the risk and choose optimal treatment for this life‐threatening disease. With the prior knowledge that asymmetric analysis of anatomical structures can provide discriminative information, plenty of symmetry‐based approaches have emerged to detect abnormalities in brain images. However, the inevitable non‐pathological noise has not been fully alleviated and weakened, leading to unsatisfactory results. A novel differential rectification and refinement network (DRRN) for the automatic segmentation of ischemic strokes is proposed. Specifically, a differential feature perception encoder (DFPE) is developed to fully exploit and propagate the bilateral quasi‐symmetry of healthy brains. In DFPE, an erasure‐rectification (ER) module is devised to rectify pseudo‐lesion features caused by non‐pathological noise through utilising discriminant features within the symmetric neighbourhood of the original image. And a differential‐attention (DA) mechanism is also integrated to fully perceive the differences in cross‐axial features and estimate the similarity of long‐range spatial context information. In addition, a crisscross differential feature reinforce module embedded with multiple boundary enhancement attention modules is designed to effectively integrate multi‐scale features and refine textual details and margins of the infarct area. Experimental results on the public ATLAS and Kaggle dataset demonstrate the effectiveness of DRRN over state‐of‐the‐arts.

Systematic Insights into the Relationship between the Microbiota–Gut–Brain Axis and Stroke with the Focus on Tryptophan Metabolism

Stroke, as a serious cerebral vascular disease with high incidence and high rates of disability and mortality, has limited therapeutic options due to the narrow time window. Compelling evidence has highlighted the significance of the gut microbiota and gut–brain axis as critical regulatory factors affecting stroke. Along the microbiota–gut–brain axis, tryptophan metabolism further acquires increasing attention for its intimate association with central nervous system diseases. For the purpose of exploring the potential role of tryptophan metabolism in stroke and providing systematic insights into the intricate connection of the microbiota–gut–brain axis with the pathological procedure of stroke, this review first summarized the practical relationship between microbiota and stroke by compiling the latest case-control research. Then, the microbiota–gut–brain axis, as well as its interaction with stroke, were comprehensively elucidated on the basis of the basic anatomical structure and physiological function. Based on the crosstalk of microbiota–gut–brain, we further focused on the tryptophan metabolism from the three major metabolic pathways, namely, the kynurenine pathway, serotonin pathway, and microbial pathway, within the axis. Moreover, the effects of tryptophan metabolism on stroke were appreciated and elaborated here, which is scarcely found in other reviews. Hopefully, the systematic illustration of the mechanisms and pathways along the microbiota–gut–brain axis will inspire more translational research from metabolic perspectives, along with more attention paid to tryptophan metabolism as a promising pharmaceutical target in order to reduce the risk of stroke, mitigate the stroke progression, and ameliorate the stroke prognosis.

Hippocampus infarct following a posterior cerebral artery occlusion.

A 64-year-old gentleman, presented for subacute onset of short-term memory problem, preceded by headache, right arm numbness and visual disturbances. On neurological exam, he had anterograde amnesia, decreased pinprick sensation on his right arm and right homonymous hemianopsia. Brain Magnetic Resonance imaging (MRI) and Magnetic Resonance Angiography (MRA) showed subacute ischemic lesions in the left occipital lobe, hippocampus and thalamus, caused by a distal occlusion of the left Posterior Cerebral Artery (PCA). A distal occlusion of the PCA led to multiple infarcts in different anatomical structures, causing a constellation of variant neurological signs. Our case demonstrates an anterior hippocampus predominantly irrigated by the PCA.

Morphological methods in the study of the anatomy and topography of the human pelvic organs and structures in the fetal period of ontogenesis

Aim to identify the features of the use of various morphological methods, their informative value, advantages and disadvantages in studying the topographic anatomy of organs and structures of the fetal pelvis of the fetus. Material and methods. The study was carried out on the material of 100 human fetuses of both sexes using classical morphological methods (macromicropreparation, the method of cutting according to N.I. Pirogov, histotopographic method). Results. Macromicroscopic dissection in the study of pelvic organs in prenatal ontogenesis makes it possible to determine the position of organs and structures, their course and direction, symmetry with respect to paired organs. Dissection makes it possible to identify vascular and nerve structures, which is necessary when interpreting data obtained using other methods. Dissection does not allow to determine the skeletotopy of the organs and structures of the pelvis, their relative position relative to each other and bone structures, the relationship with the walls of the pelvic cavity. The use of the method of cutting according to N.I. Pirogov and the histotopographic method made it possible to describe of all horizontal sections from the LIII level to the subcutaneous floor of the perineum, as well as clinically important sagittal and frontal sections, was given. These methods allow us to define the skeletotopy of the organ, its relationship with the walls of the pelvic cavity, to study the ratio of the volume of the occupied organ in the cavity, as well as measure distances. The histotopographic method makes it possible to study in detail the internal structure, microtopography of organs and neurovascular complexes of the pelvis. This is the most informative method when studying the perineum. The article presents photographs of preparations demonstrating the features of the topographic anatomy of the fetal pelvis. Conclusions. It is possible to study in detail the topographic anatomy of the fetal pelvis, as well as to give a detailed description of the skeletotopy and syntopy of each organ only when using the complex of morphological methods presented. Using this approach, the data obtained will be useful to specialists of prenatal diagnostics, as well as during fetal operations.

ОСОБЕННОСТИ СТРОЕНИЯ СЕМЯПРОВОДОВ У КРОЛИКОВ

The aim of the study is to investigate the anatomical and histological structure of the ductus deferens in representatives of the order Lagomorpha. The results of the micromorphology of the vas deferens in representatives of the order Lagomorpha are presented. Histological preparations were prepared and exami¬ned at the Omsk State Agrarian University (Department of Anatomy, Histology, Physiology and Pathological Anatomy). The objects of the study were material obtained from five sexually mature male Californian rabbits. For histological examination, pieces of organs were selected using the generally accepted method. Sections were stained with hematoxylin and eosin, as well as the Van Gieson method. Morphological, histological, morphometric and statistical methods were used in the study. The ductus deferens in rabbits is a paired tubular organ. The thickness of the mucous membrane of the left ductus deferens varies within 85.77 ± 3.13 μm, of the right ductus deferens was 136.14 ± 3.20 μm. The thickness of the muscular membrane of the left ductus deferens was 287.16 ± 3.48 μm, of the right ductus deferens was 333.79 ± 4.07 μm. The thickness of the adventitia of the left ductus deferens was 246.08 ± 4.75 μm, of the right ductus deferens was 258.56 ± 3.84 μm. During the study, special attention was paid to the adaptation of the muscular layer, which demonstrates a high degree of development and the ability to powerful peristaltic contractions, ensuring the movement of sex cells to the urethra. We can also assume the formation of sphincter systems of the ductus deferens in the indicated anatomical areas.