Mosaic Pattern Research Articles

First Detection of Atractylodes Mild Mottle Virus in Atractylodes lancea (Thunb.) DC. in Hubei Province of China.

The cultivated aromatic medicinal herb Atractylodes lancea (Thunb.) DC. is widely used in the pharmaceuticals, nutraceuticals, and cosmetics industries (Na-Bangchang et al. 2014; Zhan et al. 2023). Huanggang in Hubei Province is a major production area for A. lancea (Huang et al. 2022; Wang et al. 2023). In April 2023, more than two-thirds of the surveyed plant leaves in this region exhibited virus-like symptoms, such as curling and mosaic patterns. To identify the underlying cause, 80 symptomatic plant leaf samples were collected from four fields (20 leaves per field) in this region and pooled for virome analysis. Total RNA, including ribosomal RNA, was extracted from the pooled samples using the Plant RNA Extraction Mini Kit (Onrew Biotech, Guangdong, China), for sequencing library construction. The Illumina NovaSeq 6000 platform was used to sequence the library and generate 150 bp paired-end reads. After processing the raw data with Trimmomatic software, a total of 44,354,650 high-quality clean reads were obtained. The clean reads were aligned against ribosomal RNA using BWA software (v0.7.17) to avoid interference and eliminate corresponding sequences. After removing potential contamination, contig assembly of the clean reads was performed using Megahit software (v1.2.9). The resulting contigs were compared with the virus NT database using the BLASTn program. Sequence pairwise comparison revealed 8 contigs (574 nt to 2243 nt) with identities ranging from 81.88% to 90.77% with Atractylodes mild mottle virus (AMMV, NC_027924.1, Lim et al., 2015). Additionally, contigs mapped to Carlavirus, Pelarspovirus, and other plant viruses in our virome dataset had low coverage and pairwise identity (less than 70%), which need to be further investigated. The presence of AMMV was confirmed by aligning the clean reads to the reference sequence (NC_027924.1) using BWA and SAMtools software, resulting in a consensus sequence (8024 nt) with gaps. DNA extraction from the pooled samples was performed using the Rapid Universal Genomic DNA Extraction Kit (Simgen, Zhejiang, China). Two pairs of specific primers, 3399F (5'-AAAGAAGAACCTCCTGATACGG-3')/5924R (5'-TGAACCTGATTCTCTTGGC-3') and 1830F (5'- CTCAGGAAATCCCAATGC -3')/3640R(5'-TTTCCCAATGTTCTTCGGG-3'), were designed to amplify the complete gene sequences of polymerase and coat protein (CP), based on the consensus sequence. The PCR products with the lengths of 2521 bp and 1814 bp were cloned into the pMD18-T vector (Takara Biotech, Dalian, China) for sequencing. The BLASTn analysis showed that the polymerase and CP gene sequences shared an identity of 94.51% (1929/2041 nt) and 88.41% (1419/1605 nt) with the AMMV isolate (NC_027924.1), respectively. The sequences have been deposited in GenBank under the accession numbers OR544810 and OR544811. We collected leaves from 32 A. lancea plants (16 symptomatic and 16 asymptomatic) in the fields. RT-PCR was conducted using CPF (5'-CTGCGAATATGAAAGTGC-3') and CPR (5'-GGTGAGCTTGTCTGTTAGG-3') primers, which were designed targeting a 527bp fragment of the CP gene (OR544811). Amplicons of the expected size (527bp) were detected in 24 plants (11 symptomatic and 13 asymptomatic), three of which were sequenced by Sanger sequencing, showing a 100% match to OR544811. These findings indicate that AMMV is prevalent in the major production area of A. lancea. Further research is needed to better characterize the potential risks of AMMV to A. lancea cultivation in China as well as other countries.

Comparison between Two Adaptive Optics Methods for Imaging of Individual Retinal Pigmented Epithelial Cells.

The Retinal Pigment Epithelium (RPE) plays a prominent role in diseases such as age-related macular degeneration, but imaging individual RPE cells is challenging due to their high absorption and low autofluorescence emission. The RPE lies beneath the highly reflective photoreceptor layer (PR) and contains absorptive pigments, preventing direct backscattered light detection when the PR layer is intact. Here, we used near-infrared autofluorescence adaptive optics scanning laser ophthalmoscopy (NIRAF AOSLO) and transscleral flood imaging (TFI) in the same healthy eyes to cross-validate these approaches. Both methods revealed a consistent RPE mosaic pattern and appeared to reflect a distribution of fluorophores consistent with findings from histological studies. Interestingly, even in apparently healthy RPE, we observed dynamic changes over months, suggesting ongoing cellular activity or alterations in fluorophore distribution. These findings emphasize the value of NIRAF AOSLO and TFI in understanding RPE morphology and dynamics.

Distribution patterns and driving factors of mixed-ploidy Actinidia species in China

Polyploidization is an important driver for species formation and adaptive evolution, which results in mixed-ploidy species in the nature, i.e., one species contains at least two cytotypes. Understanding the driving factors of mixed-ploidy species offer unique insights into unraveling the evolutionary mechanisms of polyploid species. Here we investigated the distribution patterns and driving factors of 40 Actinidia species in China. Polyploid Actinidia species formed from whole-genome duplication (WGD). Actinidia species showed a mosaic geographic pattern. The potential range of mixed-ploidy Actinidia species is significantly larger than diploid and polyploid species, with higher ecological amplitude of longitude, latitude and elevation. Mixed-ploidy species showed wider temperature and water niches than diploid and polyploid species, and the tolerate capacity of mixed-ploidy species to climate extremes increased with ploidy diversity. Polyploid Actinidia species occupied niches of high altitude, low temperature and drought, supporting the niche shift hypothesis to explain the survival of polyploids. Ploidy diversity and mixed-ploidy effect was positively correlated with the ecological amplitude of temperature. Our results support that the formation and distribution of polyploidy species are associated with climate factors and adaptation capacity to abiotic stresses, and highlight the importance of mixed-ploidy species in the species formation and adaptive evolution.

Light conditions and the evolution of the visual system in birds.

Despite vision being an essential sense for many animals, the intuitively appealing notion that the visual system has been shaped by environmental light conditions is backed by insufficient evidence. Based on a comprehensive phylogenetic comparative analysis of birds, we investigate if exposure to different light conditions might have triggered evolutionary divergence in the visual system through pressures on light sensitivity, visual acuity, and neural processing capacity. Our analyses suggest that birds that have adopted nocturnal habits evolved eyes with larger corneal diameters and, to a lesser extent, longer axial length than diurnal species. However, we found no evidence that sensing and processing organs were selected together, as observed in diurnal birds. Rather than enlarging the processing centers, we found a tendency among nocturnal species to either reduce or maintain the size of the two main brain centers involved in vision-the optic tectum and the wulst. These results suggest a mosaic pattern of evolution, wherein optimization of the eye optics for efficient light capture in nocturnal species may have compromised visual acuity and central processing capacity.

Facial Segmental Infantile Haemangioma: A Cutaneous Mosaicism Quandary.

Mosaicism has long been considered the underlying mechanism of segmental infantile hemangiomas (SIH). This was a prospective pilot case-control study conducted with the objective to quantify the percentage overlap of silhouettes of facial SIH with those of Blaschko lines (the most well studied archetypical pattern of mosaicism on face) as compared to other mosaic disorders on face. Lesional silhouettes of 8 patients with SIH (Group A) and 6 patients with other facial dermatosis known to have blaschkoidal distribution (Group B), were overlapped on a standardized template with Blaschkoidal lines on the frontal view of face. The alignment was done via the auto align tool of Photoshop and the percentage of overlap was calculated with an online image comparison software (IMGonline.com.ua). There was a significant difference in mean overlap in Group A (72.92 ± 15.6 %) as compared to Group B (90.1 ± 4.3%; P=0.018). Hence, we concluded that facial SIH do not follow lines of Blaschko.

Raw Spectral Filter Array Imaging for Scene Recognition.

Scene recognition is the task of identifying the environment shown in an image. Spectral filter array cameras allow for fast capture of multispectral images. Scene recognition in multispectral images is usually performed after demosaicing the raw image. Along with adding latency, this makes the classification algorithm limited by the artifacts produced by the demosaicing process. This work explores scene recognition performed on raw spectral filter array images using convolutional neural networks. For this purpose, a new raw image dataset is collected for scene recognition with a spectral filter array camera. The classification is performed using a model constructed based on the pretrained Places-CNN. This model utilizes all nine channels of spectral information in the images. A label mapping scheme is also applied to classify the new dataset. Experiments are conducted with different pre-processing steps applied on the raw images and the results are compared. Higher-resolution images are found to perform better even if they contain mosaic patterns.

Retinal Structure of Poecilia sphenops: Photoreceptor Mosaics, Synaptic Ribbon Patterns, and Glial Cell Expressions.

The specific arrangement and distribution of photoreceptors in the retina can vary among different fish species, with each species exhibiting adaptations related to its habitat, behavior, and visual requirements. Poecilia sphenops, a diurnal fish, was the focus of this study. The retinas of a total of eighteen Molly fish were investigated utilizing light and electron microscopy. The retina exhibited a square mosaic pattern of the inner segments of cones. This pattern comprised double cones positioned along the sides of a square, with two types of single cones situated at the center and corners of the square arrangement across the entire retina. The corner cones were slightly shorter than the central ones. Additionally, the outer plexiform layer contained both cone pedicles and rod spherules. The rod spherule consisted of a single synaptic ribbon arranged in a triad or quadrat junctional arrangement within the invaginating free ends of the horizontal and bipolar cell processes. On the other hand, cone pedicles have more than one synaptic ribbon in their junctional complex. The inner nuclear layer consisted of the amacrine, bipolar, Müller, and horizontal cell bodies. Müller cell processes, expressing GFAP, extended across all retinal layers, segmenting the deeper retina into alternating fascicles of optic axons and ganglion cells. The outer and inner plexiform layers showed many astrocyte cell processes expressing GFAP. In conclusion, the current study is the first record of the retinal structures of Molly fish. This study illustrated the mosaic arrangement of photoreceptors and GFAP expression patterns of astrocytes and Müller cells. The presence of three cone types, coupled with a sufficient number of rods, likely facilitates motion awareness for tasks like finding food and performing elaborate mating ceremonies.

Findings in chest angiotomographies with PET protocols

Objectives: To investígate and analyze the tomographic findings in AngioCT with PET protocol. Material and method: Tomography reports of patients undergoing AngioCT for suspected PE during the period from January 2020 to December 2022 performed at the high complexity hospital were analyzed. RESULTS: The analysis showed a significant increase in findings in 2021, associated with the frequency of pulmonary embolism (PE) in patients with SARS-CoV-2 infection. The predominant age range was 60 to 79 years. There was a slight predominance of male patients compared to female patients. Among the most common are pleural or pericardial effusion, atelectasis, and the ground glass or mosaic pattern. Conclusions: The results of this study demonstrate that CT angiography with a PET protocol is a valuable diagnostic tool in patients with suspected PE. Incidental detection of these injuries raises questions about appropriate management, follow-up, and the need for medical interventions. This phenomenon has led to a growing need to develop clear guidelines and criteria for the evaluation and management of incidentalomas found on chest PET scans. In this context, it is crucial to investigate and better understand the nature and clinical implications of these findings to improve medical decision making.

Development of a heat-stable alkaline phosphatase reporter system for cis-regulatory analysis and its application to 3D digital imaging of Xenopus embryonic tissues.

Xenopus is one of the essential model systems for studying vertebrate development. However, one drawback of this system is that, because of the opacity of Xenopus embryos, 3D imaging analysis is limited to surface structures, explant cultures, and post-embryonic tadpoles. To develop a technique for 3D tissue/organ imaging in whole Xenopus embryos, we identified optimal conditions for using placental alkaline phosphatase (PLAP) as a transgenic reporter and applied it to the correlative light microscopy and block-face imaging (CoMBI) method for visualization of PLAP-expressing tissues/organs. In embryos whose endogenous alkaline phosphatase activities were heat-inactivated, PLAP staining visualized various tissue-specific enhancer/promoter activities in a manner consistent with green fluorescent protein (GFP) fluorescence. Furthermore, PLAP staining appeared to be more sensitive than GFP fluorescence as a reporter, and the resulting expression patterns were not mosaic, in striking contrast to the mosaic staining pattern of β-galactosidase expressed from the lacZ gene that was introduced by the same transgenesis method. Owing to efficient penetration of alkaline phosphatase substrates, PLAP activity was detected in deep tissues, such as the developing brain, spinal cord, heart, and somites, by whole-mount staining. The stained embryos were analyzed by the CoMBI method, resulting in the digital reconstruction of 3D images of the PLAP-expressing tissues. These results demonstrate the efficacy of the PLAP reporter system for detecting enhancer/promoter activities driving deep tissue expression and its combination with the CoMBI method as a powerful approach for 3D digital imaging analysis of specific tissue/organ structures in Xenopus embryos.

Bronquiolitis obliterante posinfecciosa secundaria a adenovirus

Bronchiolitis obliterans is a rare chronic obstructive respiratory disease secondary to damage of the lower respiratory tract causing inflammation and partial or total obliteration of it. There are different causes, being infectious the most frequent in pediatrics, mainly due to adenovirus. We present the case of an 18-month-old male infant with a history of admission to the Pediatric Intensive Care Unit at 8 months of age due to bronchitis secondary to respiratory syncytial virus and adenovirus. After this episode, he presented persistent respiratory distress and pathological pulmonary auscultation. High resolution pulmonary computed tomography showed a mosaic pattern with areas of air trapping and decreased vascular caliber in the affected areas, findings suggestive of bronchiolitis obliterans.

Subclinical pleuro-pulmonary disease in patients with SLE: functional and radiological methods

Abstract Background Systemic lupus erythematosus (SLE) is a multisystem autoimmune disease with highest prevalence of chest involvement; however, early detection of subclinical pleuropulmonary diseases may improve the quality of life and prognosis of patients. This study aimed to identify the subclinical pleuro-pulmonary involvement in SLE patients without respiratory symptoms. Methods A total of 228 patients diagnosed with SLE were recruited and subjected to high-resolution computed tomography (HRCT) chest, ultrasound (US) chest, and spirometry for further evaluation and finding of sub-clinical signs. Results Around 52.63% of patients had pulmonary involvement in HRCT, while in US, it was 73.68%. Ground glass opacity was observed in 31.58% of HRCT cases, and > 1/3 of patients had pleural thickness in US. Spirometry showed that 26.32% of patients had small airway disease. SLE patients with subclinical lung involvement were significantly female and younger and had shorter disease duration, p < 0.05 for all. SLE severity showed a significant negative correlation with lung function, and was positively correlated with pleural thickness and effusion, and pleural nodules in US finding. However, diaphragmatic excursion showed a negative correlation. Moreover, ground glass opacities, honey combing opacities, interlobular septal thickening, pleural thickness, and effusion in HRCT showed positive correlation with disease severity, p < 0.001 for all, yet, the mosaic pattern showed a negative relationship. Conclusion The radiological assessments of SLE patients via HRCT and ultrasound unveiled prevalent findings such as ground glass opacities and pleural abnormalities. The severity of SLE correlated significantly with pulmonary function tests in a negative way, plus the positive correlation with lung opacities and pleural abnormalities.

A172 A CLASSIC CASE OF WHIPPLE'S DISEASE

Abstract Background Whipple’s disease is a systemic disorder caused by the Gram-positive bacillus Tropheryma whippelii. It is classically defined by the four cardinal clinical manifestations of arthralgias, weight loss, diarrhea and abdominal pain. Classic Whipple’s disease is considered extremely rare, with an estimated global incidence of 30 cases per year, though this may be an underestimate. Aims To present a case of classic Whipple’s disease, so as to raise awareness and clinical suspicion for this rare condition. Methods We performed a retrospective chart review of a case of classic Whipple’s disease diagnosed in Saint John, NB, in 2020. Results A 55-year-old female presented to hospital with intractable weakness and diarrhea. Her history was notable for several years of right leg weakness, myalgias and low-grade fevers. More acutely, she presented to hospital due to worsening secretory diarrhea resulting in 15kg weight loss. Initial investigations were remarkable for an elevated C-reactive protein. The patient was admitted for coordinated evaluation for possible rheumatologic and infectious causes. As part of that workup, colonoscopy was performed. Colonoscopy revealed an abnormal ileum, with villi described as edematous with a mosaic pattern alternating between erythematous and “white tipped”. On histologic assessment, ileal biopsies showed macrophages with PAS-positive diastase resistant granules suspicious for Whipple’s disease. A follow-up esophagogastroduodenoscopy with duodenal biopsies was thus performed to gain further tissue for confirmatory testing. The duodenal mucosa was also noted to have a mosaic pattern with hypertrophic villi alternating between pale and erythematous in appearance. Duodenal biopsies were taken and sent for PCR testing. This testing was positive for T. whippelii, confirming the diagnosis of Whipple’s disease. The patient was initiated on long-term antibiotic therapy with ceftriaxone transitioning to trimethoprim-sulfamethoxazole prior to discharge. She unfortunately re-presented one month post-discharge with recurrent fevers, malaise and arthralgias. Given suspicion that her disease may be resistant to trimethoprim-sulfamethoxazole, she was transitioned to doxycycline and hydroxychloroquine as second-line therapy. She clinically improved on this regimen, and was able to be de-escalated to long-term doxycycline monotherapy after one year. At a recent follow-up, nearly three years from her initial diagnosis, she was doing well with essentially no ongoing symptoms of her Whipple’s disease. Conclusions Whipple’s disease is a rare infection presenting with intractable diarrhea and abdominal discomfort. Our case highlights the excellent clinical response that can be achieved with successful diagnosis and management of this otherwise debilitating disease. Funding Agencies None

Ehf and Fezf2 regulate late medullary thymic epithelial cell and thymic tuft cell development.

Thymic epithelial cells are indispensable for T cell maturation and selection and the induction of central immune tolerance. The self-peptide repertoire expressed by medullary thymic epithelial cells is in part regulated by the transcriptional regulator Aire (Autoimmune regulator) and the transcription factor Fezf2. Due to the high complexity of mTEC maturation stages (i.e., post-Aire, Krt10+ mTECs, and Dclk1+ Tuft mTECs) and the heterogeneity in their gene expression profiles (i.e., mosaic expression patterns), it has been challenging to identify the additional factors complementing the transcriptional regulation. We aimed to identify the transcriptional regulators involved in the regulation of mTEC development and self-peptide expression in an unbiased and genome-wide manner. We used ATAC footprinting analysis as an indirect approach to identify transcription factors involved in the gene expression regulation in mTECs, which we validated by ChIP sequencing. This study identifies Fezf2 as a regulator of the recently described thymic Tuft cells (i.e., Tuft mTECs). Furthermore, we identify that transcriptional regulators of the ELF, ESE, ERF, and PEA3 subfamily of the ETS transcription factor family and members of the Krüppel-like family of transcription factors play a role in the transcriptional regulation of genes involved in late mTEC development and promiscuous gene expression.

Differently managed reed beds are home to Coleoptera communities differing in diversity, overall biomass and size

Reed beds can be managed for commercial or conservation purposes, with effects on its inhabitants. In this paper, we assess the effect of management on the reed bed Coleoptera community by investigating reed beds subject to winter cutting, winter harvest, short-term unmanaged (3 years), and long-term unmanaged (25 years). Using pit fall traps, we collected Coleoptera across a summer season to estimate Coleoptera biomass, abundance, size, richness, diversity, and community composition across the four types of management of reed beds. Cutting and harvest both show to increase Coleoptera biomass compared to unmanaged reed beds, with the highest Coleoptera abundance found in the harvested reed bed. The species richness and diversity, on the other hand, peaked in the long-term unmanaged reed bed. Community composition differed between the different management types, and across time. Species of conservation concern were most abundant in recently managed areas. These results have implications for the conservation of the reed bed Coleoptera community. First, to maintain a high Coleoptera diversity, some areas must be left unmanaged. Secondly, to secure habitats for species of conservation concern as well as boost the Coleoptera biomass, frequent management of other areas is advised. This mosaic management pattern will also create the overall most species rich reed bed, as unique Coleoptera communities were found in each management type.

Spontaneous femoral arterio-venous fistula in an 80-year-old female patient as an incidental finding

Spontaneous arteriovenous fistulas (AVF), in contrast to iatrogenic or post-traumatic ones, are extremely rare and only sporadically published in the literature. In the absence of exposure risk, the diagnosis of AVF can be challenging, especially if it is an incidental finding. An 80-year-old female patient presented to our vascular consultation because of swelling of the left leg due to varicosis. For years, she had also noticed that the right foot seemed to be cooler. Percutaneous catheter examinations via the groin had not been performed, and she could not remember any groin injuries. Truncal varicosis of the great saphenous vein confirmed clinically and sonographically. In addition, with peripheral pulses obtained, the right foot appeared slightly cooler but not discolored. On auscultation, a systolic-diastolic murmur accompanied by palpable buzzing was heard in the right groin. Color duplex sonography showed a coarse color mosaic pattern between the common femoral artery (AFC) and the anterior saphenous vein (VSAA) in the sense of aliasing ("confetti phenomenon"). A fistula channel between the AFC and VSAA could be visualized, in which very high systolic-diastolic flow velocities prevailed; pulsatile and turbulent flow was present in the region of the crosse-near femoral vein. Endovenous laser ablation was performed for symptomatic truncal varicosis of the left leg. Under ultrasound-guided compression of the afferent artery and fistula at the right groin, the fistula flow did not stop. The patient was reluctant to undergo a proposed interventional closure of the AVF. In follow-up over 4 years, no signs of cardiac insufficiency or critical limb ischemia developed. Spontaneous femoral AVF is a rarity. Characteristic clinical findings lead to a targeted use of color duplex sonography with correct interpretation of artifacts that can otherwise be easily missed.

Iğdir İli Kabakgil Bitkilerinde Bazı Mozaik Hastalıklarının In Siliko ve Moleküler Analizi

Cucumber mosaic cucumovirus (CMV) and Watermelon mosaic potyvirus (WMV) are plant viruses with positive single-stranded RNA genome that infect cucurbits and cause economic losses. Both viruses cause especially mosaic pattern and deformities in leaves, in cucurbit plants. The leaves of 23 melon and 28 watermelon plants showing such symptoms were sampled from different regions of Iğdır province. Samples with and without symptoms were tested by the Reverse Transcription Polymerase Chain Reaction (RT-PCR) using coat protein gene (CP)-specific primers. Polymerization tests amplified DNA fragments of the expected size for CMV and WMV. Some fragments with positive results were purified, bacterial cloned, nucleotide sequences revealed and registered in the GeneBank (NCBI). Sequence analyzes showed that it contained 593 bp and 822 bp for CMV and WMV, corresponding to the partial CP gene. Phylogenetic relationships with isolates from different geographical regions and plant material were investigated for both viruses. The generated phylogenetic tree confirmed that CMV-Iğdır isolate was in Group I and subgroup B, and WMV-Iğdır isolates were in different groups. In addition, coat proteins of virus isolates were characterized by in silico tools.
 In the current study, the presence WMV of and CMV in watermelon and melon was determined for the first time in Iğdır province, and group/subgroup assignments of CMV were revealed.

Mosaic Form of Turner Syndrome

Objective: To report a case of breast growth disorder in a mosaic form of Turner Syndrome. Turner syndrome is a chromosomal condition characterized by small height and primary ovarian insufficiency that affects one in every 2500 female births. Mosaicism is likely to occur when monosomy X develops in only a few cells during development. The clinical presentation of Turner syndrome mosaicism is atypical, with symptom severity varying based on the number of affected cells. This case discusses issues with secondary sex development, including mild hyperandrogenism, and explores how combination hormonal treatment can aid in enhancing secondary sex development.
 Method: Case Report.
 Case: A 21-year-old woman presented with chief complaint of the lack of breast enlargement. She exhibited normal genitalia internally and externally and had a regular menstrual cycle. Karyotyping revealed a mosaic pattern of 45, X/46, XX (1 percent/99%) with normal estradiol levels and elevated testosterone levels (indicating mild hyperandrogenism). The patient underwent two cycles of hormone therapy using Ethinyl Estradiol and Drospirenone, resulting in breast growth progression from Tanner stage 1 to Tanner stage 2.
 Conclusion: Mosaicism in Turner syndrome is plausible, and the severity of clinical symptoms correlates with the number of defective chromosomes. The presentation of Turner syndrome mosaicism varies, and therapy should be tailored to address specific symptoms. While breast development is observed in some girls with Turner Syndrome, instances of breast growth disorder may occur, involving estrogen activity and estrogen receptor sensitivity. Although the exact cause of impaired breast growth remains unknown, administering estrogen in such cases can improve secondary sexual characteristics.
 Keywords: mild hyperandrogenism, mosaicism, turner syndrome

Temperature sensitivity of soil-borne fungal phytopathogens depends on niche breadth and land use types

Soil-borne fungal plant pathogens pose great threats to agricultural productivity and native ecosystems. However, the roles of niche breadth and land-use types in regulating the response of soil-borne fungal plant pathogens to temperature changes largely remain unclear. Here, we surveyed soil pathogens from different valleys where croplands, grasslands, and woodlands scattered in mosaic patterns. We found that pathogen richness increased with increasing temperature in grasslands but not in croplands and woodlands. After classifying the pathogens based on temperature niche, we found that the richness of specialists was sensitive to temperature changes and increased with increasing temperature in grasslands and croplands. By contrast, the richness of neutrals (those taxa not defined as generalists or specialists) did not change with temperature gradients regardless of land-use types. Additionally, pathogens were more abundant and diverse in croplands than those in grasslands and woodlands, and this pattern persisted across the temperature gradient. Our results provide evidence that temperature change and land use types could additively affect the diversity of plant pathogens in soils. This work advances our understanding of how niche breadth affects the response of pathogens to temperature, highlighting the importance of climate change and land use in regulating the abundance and diversity of pathogens.

Ontogenetic shifts in body form in the bull shark Carcharhinus leucas.

Recent studies have uncovered mosaic patterns of allometric and isometric growth underlying ontogenetic shifts in the body form of elasmobranch species (shark and rays). It is thought that shifts in trophic and spatial ecology through ontogeny drive these morphological changes; however, additional hypotheses relating to developmental constraints have also been posed. The bull shark (Carcharhinus leucas) is a large-bodied coastal shark that exhibits strong ontogenetic shifts in trophic and spatial ecology. In this study, we utilise a large data set covering a large number of morphological structures to reveal ontogenetic shifts in the body form of C. leucas, stratifying analyses by sex and size classes to provide fine-scale, more ecomorphologically relevant results. Our results indicate shifts in functional demands across the body through ontogeny, driven by selective pressures relating to trophic and spatial ecology driving the evolution of allometry. We also find significant differences in scaling trends between life stages, and between the sexes, highlighting the importance of utilising large, diverse datasets that can be stratified in this way to improve our understanding of elasmobranch morphological evolution. Ultimately, we discuss the implications of these results for existing ecomorphological hypotheses regarding the evolution of specific morphological structures, and pose novel hypotheses where relevant.

Light and electron microscopic observations on retinal neurons of red-tail shark (Epalzeorhynchos bicolor H. M. Smith, 1931).

The structure of photoreceptors (PR) and the arrangement of neurons in the retina of red-tail shark were investigated using light and electron microscopy. The PR showed a mosaic arrangement and included double cones, single cones (SC), and single rods. Most cones occur as SC. The ratio between the number of cones and rods was 3:1.39 (±0.29). The rods were tall that reached the pigmented epithelium. The outer plexiform layer (OPL) showed a complex synaptic connection between the horizontal and photoreceptor terminals that were surrounded by Müller cell processes. Electron microscopy showed that the OPL possessed both cone pedicles and rod spherules. Each rod spherule consisted of a single synaptic ribbon within the invaginating terminal endings of the horizontal cell (hc) processes. In contrast, the cone pedicles possessed many synaptic ribbons within their junctional complexes. The inner nuclear layer consisted of bipolar, amacrine, Müller cells, and hc. Müller cells possessed intermediate filaments and cell processes that can reach the outer limiting membrane and form connections with each other by desmosomes. The ganglion cells were large multipolar cells with a spherical nucleus and Nissl' bodies in their cytoplasm. The presence of different types of cones arranged in a mosaic pattern in the retina of this species favors the spatial resolution of visual objects. RESEARCH HIGHLIGHTS: This is the first study demonstrating the structure and arrangement of retinal neurons of red-tail shark using light and electron microscopy. The current study showed the presence of different types of cones arranged in a mosaic pattern that may favor the spatial resolution of visual objects in this species. The bipolar, amacrine, Müller, and horizontal cells could be demonstrated.