Distal Region Research Articles

Pre-ciliated tubal epithelial cells are prone to initiation of high-grade serous ovarian carcinoma

The distal region of the uterine (Fallopian) tube is commonly associated with high-grade serous carcinoma (HGSC), the predominant and most aggressive form of ovarian or extra-uterine cancer. Specific cell states and lineage dynamics of the adult tubal epithelium (TE) remain insufficiently understood, hindering efforts to determine the cell of origin for HGSC. Here, we report a comprehensive census of cell types and states of the mouse uterine tube. We show that distal TE cells expressing the stem/progenitor cell marker Slc1a3 can differentiate into both secretory (Ovgp1+) and ciliated (Fam183b+) cells. Inactivation of Trp53 and Rb1, whose pathways are commonly altered in HGSC, leads to elimination of targeted Slc1a3+ cells by apoptosis, thereby preventing their malignant transformation. In contrast, pre-ciliated cells (Krt5+, Prom1+, Trp73+) remain cancer-prone and give rise to serous tubal intraepithelial carcinomas and overt HGSC. These findings identify transitional pre-ciliated cells as a cancer-prone cell state and point to pre-ciliation mechanisms as diagnostic and therapeutic targets.

Structural diversity inside the mouse subiculum revealed by a new marker protein fibronectin 1.

The subiculum is one of the major output structures of the hippocampal formation and is an important brain region for memory. We have previously reported that the subiculum of rodents can be morphologically divided into its temporal (ventral) two-thirds and the septal (dorsal) third and that the former can be further subdivided into the distal (Sub1) and proximal (Sub2) regions, on a basis of immunohistochemical localizations of several Sub2-specific proteins. However, it remains unclear whether detailed structural organization found in the temporal subiculum is applicable to the septal subiculum. In this study, we found that the distribution of fibronectin (FN1)-positive non-GABAergic, presumptive pyramidal cells exactly coincided with the extent of the Sub1 region of male mice. Using FN1 immunohistochemistry, the Sub1 was found to keep relatively constant size throughout the septotemporal axis of the subiculum. In contrast, the size of the Sub2 became smaller as it approached the septal side, and the Sub2 finally disappeared at the most septal level of the subiculum. Retrograde tracer experiments confirmed that FN1-positive Sub1 neurons projected to the retrosplenial cortex, which is thought to be associated with spatial memory, whereas FN1-negative Sub2 neurons projected to the nucleus accumbens associated with emotional memory. Considering both the functional segregation of these two subicular targets and the relative abundance of the Sub2 on the temporal side, the subiculum can be one of the neural substrates for functional differences between the septal and temporal hippocampal formation associated with the spatial and emotional memory, respectively.

Clinical Anatomy of Vessels of Popliteal Region

INTRODUCTION: A modern standard for noninvasive diagnostics of the vascular system is duplex scanning. The knowledge of variability of vascular anatomy is essential for ultrasound doctors. AIM: To clarify variants of the clinical anatomy of vessels of the popliteal region using duplex scanning and anatomical preparation. MATERIALS AND METHODS: The work used data of duplex scanning of the arteries and veins of the lower extremities of patients without pathology of the vascular system of the lower extremities, who underwent examination of the vascular system: 200 patients aged from 18 to 92 years. As control, the data of anatomical preparation of 50 amputated lower extremities were taken, with preliminary filling the venous system with a blue synthetic gel. RESULTS: In the course of anatomical preparation, two trunks of the popliteal vein were identified in the distal popliteal region in 86.0% of observations. A typical drain of the small saphenous vein with formation of the saphenopopliteal junction was encountered in 60.0% of cases. In duplex scanning, a high bifurcation of the popliteal artery was detected in 1.9% of observations. The two trunks of the popliteal vein in the distal part of the popliteal region were encountered in 82.4% of cases, and the medial trunk was almost always larger than the lateral one. The small saphenous vein drained into the popliteal vein in 63.0% of cases. In 7.2% of observations, it drained into one of the intramuscular veins. In 0.95% of observations, a perforator vein was identified in the popliteal region. The sural veins were identified in all the patients — two on the medial and lateral surface positioned at the sides of the two trunks of the sural arteries, forming a single trunk before confluence with the popliteal vein. CONCLUSIONS: TThe study revealed the following anatomic variants of vessels of the popliteal region: two trunks of the popliteal vein below the knee joint cleft in 85.7% to 86.0% of observations; a high bifurcation of the popliteal artery in 1.9%; saphenopopliteal junction in 60.0% to 63.0%; perforator veins of the popliteal region in 0.95% of observations; upon that, the small saphenous vein does not form the saphenopopliteal junction.

Multiscale hamstring muscle adaptations following 9 weeks of eccentric training.

Eccentric training, such as Nordic hamstring exercise (NHE) training, is commonly used as a preventive measure for hamstring strains. Eccentric training is believed to induce lengthening of muscle fascicles and to be associated with the addition of sarcomeres in series within muscle fibers. However, the difficulty in measuring sarcomere adaptation in human muscles has severely limited information about the precise mechanisms of adaptation. This study addressed this limitation by measuring the multiscale hamstring muscle adaptations in response to 9 weeks of NHE training and 3 weeks of detraining. Twelve participants completed 9 weeks of supervised NHE training, followed by a 3-week detraining period. We assessed biceps femoris long-head (BFlh) muscle fascicle length, sarcomere length, and serial sarcomere number in the central and distal regions of the muscle. Additionally, we measured muscle volume and eccentric strength at baseline, post-training, and post-detraining. NHE training over 9 weeks induced significant architectural and strength adaptations in the BFlh muscle. Fascicle length increased by 19% in the central muscle region and 33% in the distal muscle region. NHE also induced increases in serial sarcomere number (25% in the central region and 49% in the distal region). BFlh muscle volume increased by 8%, and knee flexion strength increased by 40% with training. Following 3 weeks of detraining, fascicle length decreased by 12% in the central region and 16% in the distal region along with reductions in serial sarcomere number. Nine weeks of NHE training produced substantial, region-specific increases in BFlh muscle fascicle length, muscle volume, and force generation. The direct measurement of sarcomere lengths revealed that the increased fascicle length was accompanied by the addition of sarcomeres in series within the muscle fascicles.

Secretory Cells in Halla parthenopeia (Oenonidae): Potential Implications for the Feeding and Defence Strategies of a Carnivorous Burrowing Polychaete.

Carnivorous polychaetes are known to bear diversified and often unique anatomical and behavioural adaptations for predation and defence. Halla parthenopeia, a species known to be a specialized predator of clams, thrives in the soft bottoms of the Mediterranean Sea, holding potential for polyculture and biotechnology due to the secretion of bioactive compounds. Our objective was to provide a comprehensive description of H. parthenopeia's anatomy and microanatomy, shedding light on the relation between morphology and habitat, chemical defences, and feeding behaviour. The pharynx, housing maxillae and mandibles connected to an extensive mucus gland, occupies a considerable portion of the worm's length, reaching beyond the oesophagus. This unique gland is responsible for secreting the feeding mucus, which immobilizes and aids in the digestion of clams probably acting as a vehicle of bioactive compounds synthesized by specialized serous cells in the mouth. Moreover, H. parthenopeia combines behavioural tactics, such as burrowing, and anatomical defences to evade predators. Examination of its epidermis revealed a thick cuticle layer and abundant mucocytes secreting locomotion mucus, both of which save the worm from mechanical harm during movement. When it is preyed upon, the worm can release a substantial amount of Hallachrome, a toxic anthraquinone produced by specific cells in its distal region. This pigment, with its known antimicrobial properties, likely acts as a chemical shield in case of injury. The results suggest that the ability of H. parthenopeia to prey on bivalves and to provide mechanical protection plus defence against pathogens rely on its ability to secrete distinct types of mucus. The interplay between highly specialized microanatomical features and complex behaviours underscores its adaptation as a predator in marine benthic environments.

Feasibility of open cholangioscopy with disposable flexible endoscopes.

To determine the feasibility of open cholangioscopy using disposable flexible endoscopes in canine cadavers and describe the surgical approach. Ex vivo experimental cadaveric study. Eight canine cadavers. Cadavers ranging from 5.8 to 43.8 kg underwent open transcholecystic cholangioscopy using a disposable flexible endoscope with a 3.8 mm outer diameter and 1.2 mm working channel and the surgical approach was described. The most distal anatomical region of the biliary tree towards the duodenal papilla that was visualized with the endoscope was recorded in each cadaver. A 2.7 mm rigid endoscope and a 1.9 mm flexible endoscope were also trialed and findings recorded. Endoscopic tools were trialed and their usage recorded. The disposable flexible endoscope was feasible for visualization of the junction of the common bile duct, cystic duct, and hepatic ducts in all eight dogs. Cholangioscopy using a 2.7 mm rigid endoscope did not provide further distal visualization. The 1.9 mm flexible endoscope was able to traverse down to the level of the major duodenal papilla in a 43.8 kg cadaver. Use of certain endoscopic tools can be considered through the disposable flexible endoscope although fluid instillation was affected. A 3.8 mm disposable flexible endoscope could be placed through an open transcholecystic approach to provide intraluminal endoscopic evaluation up to the level of the junction of the common bile duct, cystic duct, and hepatic ducts in dogs without cholecystic disease. Open transcholecystic cholangioscopy with a disposable flexible endoscope could provide a low-cost diagnostic and therapeutic tool in cases of obstructive biliary disease up to the level of the common bile duct.

Comparative Analyses of Resource Allocation and Anatomical Structures in the Distal and Proximal Regions of the Scape in Dendrobium Orchids with Long Flower Longevity across Different Growth Stages

Comparative Analyses of Resource Allocation and Anatomical Structures in the Distal and Proximal Regions of the Scape in Dendrobium Orchids with Long Flower Longevity across Different Growth Stages

Regional morphological adaptations of vastus lateralis muscle in response to different progressive resistance training programs: A randomised controlled trial.

Resistance training often increases muscle size, a phenomenon known as muscle hypertrophy. These morphological adaptations were typically documented to occur in a non-uniform pattern. Investigating the specific morphological adaptations to different training programs was of interest. This study aimed to investigate two resistance training programs, a high-intensity program (HI) and a combined high-intensity with low-intensity blood flow restriction program (MIX), on morphological adaptations of vastus lateralis muscle in healthy young men. Eighteen active participants were recruited and randomly assigned to the HI (n = 10) or MIX (n = 8) groups, undergoing different 6-week resistance training programs. The training volume set was equated and progressively increased from three sets in weeks 1 and 2 to six sets, and eight sets in weeks 3-4 and 5-6, respectively. Three specific regions of vastus lateralis were assessed by magnetic resonance imaging (MRI) and ultrasound imaging (US) during pre-and post-intervention. Statistical analysis revealed statistically significant increases in muscle area at the proximal (HI: Δ12%, MIX: Δ9.2%), middle (HI: Δ8.7%, MIX: Δ9.0%), and distal (HI: Δ14%, MIX: Δ13%) regions. Additionally, both HI and MIX groups showed statistically significant increases in the sum of muscle thickness post-intervention (HI: Δ12%, MIX: Δ19%) and in the sum of fascia thickness post-intervention (HI: Δ27%, MIX: Δ54%). Despite the MIX group training with higher volume load, no statistical differences were observed between groups for any week. These findings suggested that both HI and MIX programs effectively induced increases in muscle area and sums of muscle and fascia thickness in healthy young men, allowing practitioners to choose either program based on individual preferences and constraints.

Abstract 08: Genome-wide Maps of Human Kidney Proximal Tubules and Thick Ascending Limbs of Henle reveal an Enrichment for Human Blood Pressure associated Polymorphisms

GWAS has identified >1,000 blood pressure (BP)-associated sentinel SNPs, most of which (>90%) are intronic and intergenic. How they regulate BP-relevant genes remains an open question. We hypothesized many SNPs would reside within cis -regulatory elements specific to nephron segments critical to sodium resorption such as proximal tubule (PT) and thick ascending limb (TAL). To address this, we developed chromatin state (ATAC-seq) and transcriptome (RNA-seq) maps from manually dissected human PT and medullary TAL (mTAL) segments. We identified 216,168 and 179,467 open regions in PT and mTAL, respectively, with the majority (70%) being unique to one tissue. Interestingly, peaks shared between the two segments resided more frequently in promoters, whereas unique peaks were more often found in distal introns or intergenic regions, suggesting they lie within enhancers ( Figure 1A ). Both chromatin state and transcriptomic data demonstrated a correlation between open chromatin peaks within gene promoters and mRNA levels (r=0.11; p<4.6e-16). This correlation was weaker at open regions distal to the promoter, illustrating the difficulty of mapping distal open regions to the gene(s) they regulate. We hypothesized these open regions would be enriched for BP-relevant SNPs. We curated 1,071 bp-associated SNPs and found 87 and 67 in mTAL and PT, open regions respectively, many of which are near BP-relevant genes. This enrichment was significant based on 10 4 randomizations (pValue 10 -4 ) ( Figure 1B ). We conclude that these novel tissue-specific chromatin maps can be used to identify potential mechanisms by which SNPs influence gene expression and BP. Additional studies will be needed to demonstrate both causality and molecular mechanisms.

Association of OPRD1 Gene Variants with Changes in Body Weight and Psychometric Indicators in Patients with Eating Disorders.

Objectives: This study aimed to investigate whether genetic variations in the OPRD1 gene affect psychopathological symptoms and personality dimensions in eating disorders (ED) patients and/or contribute to ED risk. Methods: The study involved 221 female patients with anorexia nervosa (AN), 88 with bulimia nervosa (BN), and 396 controls. Sixteen tag-single nucleotide polymorphisms (SNPs) in OPRD1 were identified. Psychometric evaluations were conducted using the Symptom Checklist 90 Revised (SCL-90R) and the Eating Disorders Inventory Test-2 (EDI-2). p-values obtained by regression models were corrected for multiple testing by the False Discovery Rate (FDR) method. Results: In AN patients, genotypes rs204077TT and rs169450TT were linked to lower body-mass index (BMI) values (FDR-q = 0.035 and 0.017, respectively), as was rs2234918 in a log-additive model (BMI: 18.0 ± 0.28, 17.22 ± 0.18 and 16.59 ± 0.39 for TT, TC and CC carriers, FDR-q = 0.012). Additionally, AN patients carrying the rs72665504AA genotype had higher scores in interpersonal distrust (FDR-q = 0.030), whilst BN carriers of rs513269TT and rs2873795TT showed lower scores in ineffectiveness (FDR-q = 0.041 and FDR-q = 0.021). In the AN group, BMI correlated with variability in a distal haplotype (rs508448/rs204077/rs223491, FDR-q = 0.028), which was also associated with the global positive symptom total (PST) index of SCL-90R (FDR-q = 0.048). Associations were more noticeable in BN patients; again, the distal region of the gene was linked to EDI-2 total scores (FDR-q = 0.004-0.048 for the four last haplotypes) and two global SCL-90R indices (GSI: FDR-q = 0.011 and positive symptom distress index (PSDI): FDR-q = 0.003 for the last s204077/rs2234918/rs169450 combination). No associations with ED risk were observed. Conclusions: Genetic variation in the OPRD1 gene, particularly in its distal region, is associated with BMI and psychopathological comorbidities in ED patients.

Robust optimization of geometrical properties of flow diverter stents for treating cerebral aneurysm: A proof-of-concept study

This study presents a novel approach to optimize the design of flow diverter (FD) stents for cerebral aneurysm (CA) treatment. By addressing sources of uncertainty in cardiovascular simulations, including geometrical and physical properties and boundary conditions, we aim to assess the applicability of robust optimization techniques to the FD design, establishing a foundation for acquiring robust FDs that are capable of operating consistently under various real-world scenarios. Blood flow in a simplified 2-dimensional CA and FD model was simulated through computational fluid dynamics (CFD). A design space exploration method, incorporating Latin hypercube sampling and Kriging surrogate models, was employed to obtain the optimal solution. The objective was to maximize the reduction in velocity and vorticity within the CA sac. This study used non-intrusive polynomial chaos expansion (PCE) to quantify and propagate the input uncertainties through the computational model and compute the statistical moments of velocity and vorticity reductions. To assess the effect of uncertain sources on objective functions, a sensitivity analysis method based on Sobol indices was applied. Robust optimization involved simultaneously optimizing the mean and standard deviation of velocity reduction. Additionally, we accounted for patients’ specific conditions and repeated the robust optimization. The results indicate that blood Hematocrit and inlet velocity are the most impactful uncertain sources in FD optimization. Moreover, the obtained Pareto front shows that in robust designs, FD struts are concentrated in the distal region of the CA neck, while optimal designs have more struts in the proximal region. This study proposes an FD that compromises robustness and optimality with a velocity reduction of 72.31 % and a standard deviation of 0.00343.

One-year clinical evaluation of bone-level and tissue-level implants

Aim: This study aimed to retrospectively examine and compare the clinical conditions of different implant levels at the end of 1 year. The clinical success is closely related to the loading time, the primary stability, oral hygiene, the features of the implant neck, and the bone structure. Methodology: A total of 41 implants were applied to patients with a mean age of 52.76±11.39 years. Among these patients, 10 (47.6%) were female, and 11 (52.4%) were male. Out of the total of 19 implants, 46.3% were placed in the left mandible. Specifically, 14.6% were placed in the premolar area and 31.7% were placed in the molar region. The 22 (53.7%) remaining cases were placed in the right mandible, with 10 (24.4%) in the premolar region and 12 (29.3%) in the molar region. In all, 21 implants (51.2%) were placed at the bone level, whereas 20 implants (48.8%) were placed at the tissue level. Out of the total of 41 implants, 25 (61%) had a diameter of 3.3 mm, whereas 16 (39%) had a diameter of 4.1 mm. X-rays were taken to detect bone loss in the mesial and distal regions, transferred to the computer, and evaluated via IBM SPSS Statistics V22 software. Results: In the study, 19 (46.3%) of the implants were placed in the left mandible and 22 (53.7%) in the right mandible. Approximately 51.2% of the implants were placed at the bone level, and 48.8% were at the tissue level. Initial Osstell values ranged from 72.88 ± 6.4 ISQ to 75.83 ± 5.92 ISQ. The initial X-ray results varied between 0.03 ± 0.09 mm and 0.38 ± 0.99 mm, whereas the final X-ray measurements were 0.15 ± 0.24 mm to 0.71 ± 1.54 mm. Conclusion: Bone loss was determined to be less than 2 mm in both groups. Plaque accumulation occurred in the lingual region; however, it was observed more at the bone level. Hygiene control is the key for success, which could easily be accomplished with the gingival level of implants or the gingival positioning height of the abutments. How to cite this article: Sözkes S, Kayabay G, Koçak Büyükdere A. One-year clinical evaluation of bone-level and tissue-level implants. Int Dent Res 2024;14(2):50-56. https://doi.org/10.5577/idr2024.392

Bone Mineral Density and Clinical Outcome after Ankle Fracture.

No gold standard exists for bone mineral density (BMD) measurement of the ankle. This study aimed to determine the correlation between bone density using Hounsfield units (HU) based on computed tomography (CT) and BMD using dual energy X-ray absorptiometry (DXA) as well as to evaluate the correlation between HU and clinical outcome of ankle fracture. Fifty-one patients aged ≥65 years who underwent surgical treatment for trimalleolus or bimalleolus ankle fractures were included. The HU were measured at the distal tibia metaphyseal region approximately 1 cm proximal to the plafond on the axial images of preoperative CT. BMD was measured using DXA within one year before the injury. The clinical outcome was evaluated according to the Foot and Ankle Outcome Score (FAOS). Although the HU of an osteoporosis group was lower than that of a non-osteoporosis group, we observed no significant difference between the two groups. The mean HU significantly correlated with the lumbar and total lumbar spine BMD using DXA. Increased HU significantly correlated with improved clinical outcomes in three of five FAOS subscales: symptoms, pain, activity of daily living (ADL), and quality of life (QOL). In a linear regression analysis adjusted for age and body mass index, increased HU significantly correlated with improved clinical outcomes in three of five FAOS subscales: symptoms, pain, ADL, and QOL. The correlations between bone density using HU and BMD and those between HU and the clinical outcome were confirmed in ankle fractures. The HU of preoperative CT might provide valuable information for predicting postoperative clinical outcomes.

Histone H3.3 lysine 9 and 27 control repressive chromatin at cryptic enhancers and bivalent promoters

Histone modifications are associated with distinct transcriptional states, but it is unclear whether they instruct gene expression. To investigate this, we mutate histone H3.3 K9 and K27 residues in mouse embryonic stem cells (mESCs). Here, we find that H3.3K9 is essential for controlling specific distal intergenic regions and for proper H3K27me3 deposition at promoters. The H3.3K9A mutation resulted in decreased H3K9me3 at regions encompassing endogenous retroviruses and induced a gain of H3K27ac and nascent transcription. These changes in the chromatin environment unleash cryptic enhancers, resulting in the activation of distinctive transcriptional programs and culminating in protein expression normally restricted to specialized immune cell types. The H3.3K27A mutant disrupts the deposition and spreading of the repressive H3K27me3 mark, particularly impacting bivalent genes with higher basal levels of H3.3 at promoters. Therefore, H3.3K9 and K27 crucially orchestrate repressive chromatin states at cis-regulatory elements and bivalent promoters, respectively, and instruct proper transcription in mESCs.

Profiling of chromatin accessibility and regulatory elements toward understanding the mechanisms underlying growth regulation in the Pacific oyster (Crassostrea gigas)

Changes in phenotype are precisely controlled by transcriptional regulators, which depend on chromatin remodeling. Although artificial genetic breeding has significantly improved the growth performance of the Pacific oyster (Crassostrea gigas), the identification of gene regulatory elements and transcription factors related to growth is obscure. In this study, we performed a genome-wide characterization of chromatin accessibility using two strains of C. gigas that exhibit significant differences in growth. The results showed that accessible chromatin regions were mainly distributed in the noncoding regions of the genome, with a greater proportion of distal intergenic regions than that of promoters and introns. A total of 2044 differentially accessible regions and 2574 differentially expressed genes were identified through comparative analysis. Genes annotated from regions with differential chromatin accessibility were enriched in cell adhesion molecules, JAK-STAT, insulin resistance, HIF-1α, and platelet activation signaling pathways. Correlation analysis of ATAC-seq and RNA-seq data showed that differential gene expression was positively correlated with differential chromatin accessibility. Furthermore, motif screening and identification of accessible chromatin regions revealed a set of transcription factors, including LHX3, TCF7L2, and LEF1, that may play important roles in the growth of C. gigas. Integrated analysis with public Hi-C datasets allowed the identification of a differential peak located 47 kb upstream of angiopoietin-2, which may act as a potential enhancer that affects the growth of C. gigas. In summary, our work contributes to a better understanding of growth-related regulation in C. gigas and provides valuable information for deciphering the economic traits underlying growth, which is conducive to the development of the breeding industry of C. gigas in the future.

Advantages of customization of osseointegrated implants in transfemoral amputees: a comparative analysis of surgical planning

BackgroundCommercially available osseointegrated devices for transfemoral amputees are limited in size and thus fail to meet the significant anatomical variability in the femoral medullary canal. This study aimed to develop a customized osseointegrated stem to better accommodate a variety of femoral anatomies in transfemoral amputees than off-the-shelf stems. Customization is expected to enhance cortical bone preservation and increase the stem-bone contact area, which are critical for the long-term stability and success of implants.MethodsA customized stem (OsteoCustom) was designed based on the statistical shape variability of the medullary canal. The implantability of the OsteoCustom stem was tested via 70 computed tomography (CT) images of human femurs and compared to that of a commercial device (OFI-C) for two different resection levels. The evaluations included the volume of cortical bone removed and the percentage of stem-bone contact area for both resection levels. Statistical significance was analyzed using paired and unpaired t tests.ResultsThe OsteoCustom stem could be virtually implanted in all 70 femurs, while the OFI-C was unsuitable in 19 cases due to insufficient cortical thickness after implantation, further emphasizing its adaptability to varying anatomical conditions. The OsteoCustom stem preserved a greater volume of cortical bone than did the OFI-C. In fact, 42% less bone was removed at the proximal resection level (3.15 cm³ vs. 5.42 cm³, p ≤ 0.0001), and 33% less at the distal resection level (2.25 cm³ vs. 3.39 cm³, p = 0.003). The stem-bone contact area was also greater for the OsteoCustom stem, particularly at the distal resection level, showing a 20% increase in contact area (52.3% vs. 32.2%, p = 0.002) compared to that of the OFI-C.ConclusionsThe OsteoCustom stem performed better than the commercial stem by preserving more cortical bone and achieving a greater stem–bone contact area, especially at distal resection levels where the shape of the medullary canal exhibits more inter-subject variability. Optimal fit in the distal region is of paramount importance for ensuring the stability of osseointegrated implants. This study highlights the potential benefits of customized osseointegrated stems in accommodating a broader range of femoral anatomies, with enhanced fit in the medullary canal.

Efficacy of superficial femoral artery as a recipient in free flap reconstruction around the knee: Four case reports and a literature review

PurposeReconstructing soft tissue defects around the knee with free flaps presents challenges in recipient vessel selection. Although the superficial femoral artery (SFA) offers exposure ease and anatomical stability, concerns arise regarding its distance from the defect site, difficulty in performing anastomosis and potential peripheral ischaemia. This study aimed to reassess the suitability of SFA as a recipient vessel for knee reconstructions by examining our cases and those from previous reports. MethodsWe reviewed four cases of knee soft tissue defects reconstructed with free flaps using the SFA, detailing surgical techniques and outcomes. Additionally, a comprehensive literature search was conducted for articles on using SFA as a recipient vessel for knee free flaps, using PubMed, Web of Science and EBSCOhost databases. ResultsIn all four cases, latissimus dorsi (LD) flaps were used, with end-to-side anastomosis performed using a large slit-shaped arteriotomy. All flaps demonstrated successful survival without complications. Our analysis included 85 cases, comprising four of our cases and 81 cases from 16 articles. Sarcoma resection was the most common aetiology, followed by total knee prosthesis-related defects, trauma and osteomyelitis. Complete flap necrosis occurred in 5% of cases. The LD flap was the predominant choice, alongside other long-pedicle flaps. The SFA provided coverage for all knee areas except the distal lateral patellar region. ConclusionDespite the limited evidence, the SFA appears to be a reliable recipient vessel for knee soft tissue reconstruction. Comprehensive understanding of the characteristics of the SFA and flaps used enhances the safety and efficacy of soft tissue defect reconstruction around the knee.

Contrast-free visualization of distal trigeminal nerve segments using MR neurography.

The 3-dimensional cranial nerve imaging (CRANI) sequence may assist visualization of anatomical details of extraforaminal cranial nerves and aid in clinical diagnosis and preoperative planning. In this study, we investigated the feasibility of using a combined CRANI and magnetization-prepared rapid-acquisition gradient-echo (MPRAGE) imaging protocol to comprehensively identify trigeminal nerve projections. We evaluated the detection of distal regions of three branches of the ophthalmic nerve (V1), three branches of the maxillary nerve (V2), and five branches of the mandibular nerve (V3) in seven healthy adult subjects, with and without contrast injection. Nerve branches were rated on a 5-point scale by three observers. Interobserver reliability was studied using weighted kappa statistics and percentage agreement. Among V1 and V2 branches, the frontal nerve and infraorbital nerve were most successfully identified (average rating of 3.9, agreement >80%) in precontrast MPRAGE images. In V3 branches, lingual and inferior alveolar nerves were most successfully identified (average rating of 3.9, agreement >80%) in precontrast CRANI images, with an excellent average rating. In all cases except one, interobserver reliability was rated good to excellent. The buccal nerve was the only branch with a low average interobserver rating. Gadolinium contrast did not improve nerve segment visualization in our study. This may relate to the specific anatomic regions assessed, gadolinium dose, postcontrast image timing, and lack of pathology. A combined CRANI and MPRAGE protocol can be combined to visualize distal branches of V1, V2, and V3 and has potential for clinical use.

A florigen-expressing subpopulation of companion cells expresses other small proteins and reveals a nitrogen-sensitive FT repressor.

The precise onset of flowering is crucial to ensure successful plant reproduction. The gene FLOWERING LOCUS T (FT) encodes florigen, a mobile signal produced in leaves that initiates flowering at the shoot apical meristem. In response to seasonal changes, FT is induced in phloem companion cells located in distal leaf regions. Thus far, a detailed molecular characterization of the FT-expressing cells has been lacking. Here, we used bulk nuclei RNA-seq and single nuclei RNA (snRNA)-seq to investigate gene expression in FT-expressing cells and other phloem companion cells. Our bulk nuclei RNA-seq demonstrated that FT-expressing cells in cotyledons and in true leaves differed transcriptionally. Within the true leaves, our snRNA-seq analysis revealed that companion cells with high FT expression form a unique cluster in which many genes involved in ATP biosynthesis are highly upregulated. The cluster also expresses other genes encoding small proteins, including the flowering and stem growth inducer FPF1-LIKE PROTEIN 1 (FLP1) and the anti-florigen BROTHER OF FT AND TFL1 (BFT). In addition, we found that the promoters of FT and the genes co-expressed with FT in the cluster were enriched for the consensus binding motifs of NITRATE-INDUCIBLE GARP-TYPE TRANSCRIPTIONAL REPRESSOR 1 (NIGT1). Overexpression of the paralogous NIGT1.2 and NIGT1.4 repressed FT expression and significantly delayed flowering under nitrogen-rich conditions, consistent with NIGT1s acting as nitrogen-dependent FT repressors. Taken together, our results demonstrate that major FT-expressing cells show a distinct expression profile that suggests that these cells may produce multiple systemic signals to regulate plant growth and development.

Fine mapping of stem rust resistance derived from soft red winter wheat cultivar AGS2000 to an NLR gene cluster on chromosome 6D

The Puccinia graminis f. sp. tritici (Pgt) Ug99-emerging virulent races present a major challenge to global wheat production. To meet present and future needs, new sources of resistance must be found. Identification of markers that allow tracking of resistance genes is needed for deployment strategies to combat highly virulent pathogen races. Field evaluation of a DH population located a QTL for stem rust (Sr) resistance, QSr.nc-6D from the breeding line MD01W28-08-11 to the distal region of chromosome arm 6DS where Sr resistance genes Sr42, SrCad, and SrTmp have been identified. A locus for seedling resistance to Pgt race TTKSK was identified in a DH population and an RIL population derived from the cross AGS2000 × LA95135. The resistant cultivar AGS2000 is in the pedigree of MD01W28-08-11 and our results suggest that it is the source of Sr resistance in this breeding line. We exploited published markers and exome capture data to enrich marker density in a 10 Mb region flanking QSr.nc-6D. Our fine mapping in heterozygous inbred families identified three markers co-segregating with resistance and delimited QSr.nc-6D to a 1.3 Mb region. We further exploited information from other genome assemblies and identified collinear regions of 6DS harboring clusters of NLR genes. Evaluation of KASP assays corresponding to our co-segregating SNP suggests that they can be used to track this Sr resistance in breeding programs. However, our results also underscore the challenges posed in identifying genes underlying resistance in such complex regions in the absence of genome sequence from the resistant genotypes.