Visible Fibers Research Articles

An Elastin-Derived Composite Matrix for Enhanced Vascularized and Innervated Bone Tissue Reconstruction: From Material Development to Preclinical Evaluation.

Despite progress in bone tissue engineering, reconstruction of large bone defects remains an important clinical challenge. Here, a biomaterial designed to recruit bone cells, endothelial cells, and neuronal fibers within the same matrix is developed, enabling bone tissue regeneration. The bioactive matrix is based on modified elastin-like polypeptides (ELPs) grafted with laminin-derived adhesion peptides IKVAV and YIGSR, and the SNA15 peptide for retention of hydroxyapatite (HA) particles. The composite matrix shows suitable porosity, interconnectivity, biocompatibility for endothelial cells, and the ability to support neurites outgrowth by sensory neurons. Subcutaneous implantation leads to the formation of osteoid tissue, characterized by the presence of bone cells, vascular networks, and neuronal structures, while minimizing inflammation. Using a rat femoral condyle defect model, longitudinal micro-CT analysis is performed, which demonstrates a significant increase in the volume of mineralized tissue when using the ELP-based matrix compared to empty defects and a commercially available control (Collapat). Furthermore, visible blood vessel networks and nerve fibers are observed within the lesions after a period of two weeks. By incorporating multiple key components that support cell growth, mineralization, and tissue integration, this ELP-based composite matrix provides a holistic and versatile solution to enhance bone tissue regeneration.

A case of iridoschisis with partial lens dislocation in both eyes

BackgroundIridoschisis is a rare condition that primarily affects individuals aged 60–70 years. The predominant characteristics of iridoschisis involve the tissue splitting and separation of the iris stromal layers, often resulting in two distinct layers and the presence of floating fibers in the anterior chamber. This article reports the case of a 48-year-old male with iridoschisis with partial lens dislocation in both eyes.Case presentationTrauma is the leading factor in the development of iridoschisis. However, there is no documented case of ocular trauma in the patient’s medical history. Visible white atrophic fibers were observed bilaterally in the anterior iris stroma of both eyes of the individual, accompanied by a small quantity of iris tissue within the anterior chamber. In this instance, the magnitude of the iridoschisis corresponded with the degree of lens dislocation. We were apprised that the patient had regularly used a cervical massager for a prolonged period of time, positioning it upon the ocular region. Frequent stimulation of both eyes with excessive force resulted in the development of iridoschisis and the partial dislocation of the lens.During the initial surgical procedure, phacoemulsification (Phaco) was carried out on the left eye without the placement of an intraocular lens (IOL). Following a two-month interval, we proceeded with the IOL suspension. Subsequently, the right eye underwent Phaco, accompanied by the implantation of an IOL. After closely monitoring the patient’s progress for two months, it was evident that their vision had significantly improved, substantiating the success of the surgical interventions.ConclusionsThis finding posits that the recurrent friction applied to both eyes may induce iridoschisis and various ocular complications. In the event of ocular intricacies manifesting, expeditious medical intervention becomes imperative.

Effect of NaOH Concentration in The Pulping Process on Yield and Organoleptic of Art Paper from Citronella Distillation Waste

Many types of paper are on the market according to their intended use. Art paper is a type of paper with an attractive appearance, aesthetically rich in natural and unique nuances used by most craftsmen. Making art paper usually uses cellulose fiber that comes from trees, so it has an impact on deforestation. This research aims to use fragrant citronella waste as an alternative to trees as raw material for paper. Lemon grass and the availability of distillate waste which has a high enough cellulose content as a raw material for paper. The method in this study is the manufacture of pulp through the alkaline method. The analysis of organoleptic properties includes surface texture, appearance, color, and degree of whiteness. The treatment in making art paper is the difference in NaOH concentration of 5%, 7%, 9%, 11% and 13%. Analysis of organoleptic properties includes surface texture, appearance, colour, and degree of whiteness. The design used in this study was a completely randomised design with 3 replications. Data were analysed using ANOVA and Duncan's test at a significant level of 0.05.. The results showed that the yield of citronella distillation waste pulp ranged from 32.53 to 34.59%. The organoleptic properties of citronella waste art paper panelists' assessment of art paper products varied greatly. Brighter colors tend to be preferred over brownish colors, the rough texture and the appearance of visible fibers make art paper more attractive. The degree of whiteness of the resulting art paper ranges from 43.39 – 48.95%

Improving the quality of gluten-free plant-based meat analogs based on soy protein isolate with insoluble soy fibers and low acyl gellan gum

This study describes the effects of incorporating insoluble soy fiber and low acyl gellan gum as an alternative for wheat gluten in plant-based meat analogs made from soy protein isolate (SPI). The formulations containing insoluble soy fiber (ranging from 0 to 3%) and low acyl gellan gum (0–2%) were processed in a high-temperature shear cell (HTSC) and then analyzed in terms of macrostructure, microstructure, rheological properties, tensile strength, and water absorption capacity (WAC). Macrostructural analysis revealed that the control product containing SPI without insoluble soy fiber and low acyl gellan gum exhibited a dense and gel-like structure, devoid of visible fibers. The addition of 1, 2, and 3 wt.% of insoluble soy fiber increased the formation of visually elongated fibers in both macro- and microscopic levels in the shear direction, resulting in anisotropic plant-based meat analogs with improved tensile strength and elasticity. The use of 1 and 2 wt.% low acyl gellan gum led to the formation of short and thin filaments that were less oriented in the shear direction, resulting in decreased tensile strength. When combined with low acyl gellan gum, insoluble soy fiber failed to produce lengthy and elongated fibers, resulting in short and thin fibrils. These findings suggest that the interaction between insoluble soy fiber and low acyl gellan gum under the processing conditions may hinder fiber formation and mechanical anisotropy. Microscopic examination reveals smoother regions in products enriched with insoluble soy fiber and rougher surfaces in those containing low acyl gellan gum. Moreover, X-ray microtomography confirms that insoluble soy fiber enhanced air retention, contributing to enhanced structural integrity. In contrast, low acyl gellan gum introduces irregularly shaped air bubbles, compromising structural improvement. In summary, this study underscores the potential of insoluble soy fiber to enhance the structural and the textural properties of plant-based meat analogs. However, it also highlights the challenges posed by low acyl gellan gum, which, despite improving water retention, may hinder fiber formation and mechanical anisotropy. These findings offer insights for advancing the quality of plant-based meat products.

The Administration of Spinal or Local Anesthesia in Anal Fissure and Hemorrhoidectomy: A Comparative Literature Review

The purpose of this review is to consider the risks, benefits, and prospective benefits of spinal and local anesthetic. Comparing the safest and most suitable anesthetic to utilize with each surgical technique also helps. An extremely sensitive area of the human body is the anorectal region. Although it is normally shorter than the remainder of the gastrointestinal system, measuring between 2.5 and 4 cm, it is extremely complex physically and functionally. The anal canal's only purpose is to serve as a link between the rectum and the digestive system. It is crucial for maintaining fecal continence and safeguards the body against foreign bacteria that may utilize the rectum as a possible entrance point into the anal canal. Anorectal anal fissures are a typical, benign disorder. It is an extremely painful disease that, in certain extreme situations, may also cause per rectal hemorrhage. Usually an ulcer, it develops longitudinally in the anus's epithelial lining immediately distal to the dentate line. A fissure-in-ano is characterized by indurated margins, visible internal anal sphincter fibers, and a polyp or skin tag close to the fissure's distal end. Hemorrhoids are little clusters of arteriovenous, fibrovascular, and submucosal sinusoids that are located in the anorectal area. Hemorrhoids are shown to be related with new per rectal bleeding in the patients shortly after they defecate, which is a highly distinctive pattern. In circumstances where medical therapy is ineffective, surgery has been suggested for both of these disorders. Any time surgery is scheduled, the question of selecting anesthetic arises. Although both local and spinal anesthesia are advised, studies and expert views have shown that local anesthetic has a clear advantage over spinal anesthesia. It is a popular option for many surgeons since it is successful in terms of the patient's health and is also economical.

#3197 A NOVEL INVESTIGATION OF AVF WITH A SECOND HARMONIC GENERATION MICROSCOPY IN PATIENTS WITH END STAGE RENAL DISEASE

Abstract Background and Aims The population of patients with end-stage renal disease is rapidly growing and hemodialysis (HD) remains the most common treatment option. In clinical practice, the formation of arteriovenous fistulas (AVFs) is considered a priority in order to ensure optimal vascular access for HD patients. One of the complications in the formation of AVF is the hyperplasia of the neointimal layer of the vein, which leads to the failure of the fistula. The impact of the arrangement of collagen fibers in the veins of AVFs is little studied and opens wide opportunities for investigations. The structural tissue can be imaged with polarimetric nonlinear microscopy. Collagen fibers have a non-centrosymmetric structure, so they can be effectively imaged by second harmonic generation (SHG) microscopy [1]. The polarimetric nonlinear microscopy, exploiting the multidimentional tensor nature of light-matter interactions, is emerging as a valuable research tool in biomedical investigations and applications to digital pathology, and is only now becoming technically feasible for potential clinical translation [2,3]. This proposal represents a novel application of multimodal polarimetric nonlinear microscopy in histopathology, and biomedical imaging. The aim of this study is to determine the influence of the arrangement of collagen fibers in veins on the formation efficiency of AVFs by using the innovative method of nonlinear SHG microscopy. Method In this prospective study, we first used a novel SHG microscopy method to investigate AVFs venous intima hyperplasia. V. Cephalica segment is being obtained during arteriovenous fistula formation surgery from patients with end stage renal disease and after the removal of aneurysmatic or fibrotic AVF. Cross-sections of venous specimens are being fixed in 10% buffered formalin and stained with hematoxylin and eosin (H&E). Further, sample investigation is being performed in Laser Research Centre, Vilnius University using a home-built multiphoton laser-scanning microscope. The investigation is being performed with the permission of Lithuanian Biomedical Research Ethics Committee. Results We determined the arrangement of collagen fibers in veins before AVF formation and after the removal of aneurysmatic AVFs. It was observed that tunica intima of V. Cephalica is dominated both by endothelial cells and connective tissue made up of high-density collagen fibers. Whereas tunica adventitia consists mainly of collagen fibers. Collagen in tunica intima and adventitia are found to be highly noncentrosymmetric. Thus a strong SHG signal, resulting in high-contrast structural visualization of the V. Cephalica segment is generated. Conclusion Our initial investigations of AVF show clearly visible collagen fibers. The future work will focus on the structural changes of collagen fibers in the vein intimal hyperplasia. Further investigations need to be done to create artificial intelligence-based identification of new predictive collagen markers.

Quality improvement of plant-based meat alternatives by addition of iota carrageenan to pea protein–wheat gluten blend

In this study, the influence of iota carrageenan (IC) addition at different steps to the protein blends based on pea protein isolate (PPI) and wheat gluten (WG) as well as hydration mixing time and temperature of IC on the quality attributes of plant-based meat alternatives was studied. In more detail, IC was added before (B, in water with mixing times of 15 or 30 min and temperatures of 25 or 75 °C) or after (A, in powder form) the addition of PPI to the mixture with or without calcium chloride (Ca) in the formulation. The results showed that the addition of IC after PPI, especially combination with Ca resulted in the products with the most visible fibers, which can be considered as a quality improvement. IC addition to the formulations with or without Ca also increased the browning index, water holding capacity, tensile stress, and air bubble numbers compared to the PPI.WG formulation. However, no considerable difference in these parameters was found regarding the addition order of IC (before or after the addition of PPI). As the addition of IC after PPI hydration needs less energy for mixing, and, thus, less time for preparation, this order of addition can be recommended for improving the quality of plant-based meat alternatives containing IC. Therefore, hydration of IC in water, especially at high temperatures, is not necessary for the production of plant-based meat alternatives produced in the high-temperature shear cell (HTSC).

An observational study comparing and non-surgical treatment with surgical treatment for chronic anal fissures

Background: Chronic anal fissure is a common benign anorectal condition that causes significant morbidity. Symptoms consist primarily of pain and bleeding during defecation. Fissures are predominantly located in the posterior midline, but 25% of women and 8% of men have anterior fissures. Aims and Objectives: The aim of the study is to determine the outcome of various nonsurgical therapy for chronic anal fissure and comparison with the outcome of surgical treatment. Materials and Methods: This study was a non-randomized and observational study. All patients referred to the department of general surgery between December 2012 and November 2014 for a chronic anal fissure were included in the study, above the age of 12 years, and diagnosed to have anal fissure (Both Acute and Chronic) were included in the study. Results: Seventy-nine patients (91.9%) were having symptoms of pain; this pain was persistent for hours after defecation in 67 (78%) patients. Seventy-one (82.6%) patients complained of at least one episode of bleeding per Anum, other symptoms were perianal lump (10.5%), perianal itching (23.3%), and perianal discharge (30.2%). The examination findings of these patients revealed that 81 patients (94%) had developed sentinelpiles subsequently and anal fissure with visible fibers of underlying muscle were seen in 9 (10.5%) patients. Conclusion: Chronic anal fissures can be simply and effectively treated medically without the risk of incontinence associated with sphincterotomy. Topical nifedipine and botulinum toxin injections are an excellent combination, associated with a low recurrence rate and minimal side effects.

Endocrine Disruptor Bisphenol a Affects the Neurochemical Profile of Nerve Fibers in the Aortic Arch Wall in the Domestic Pig.

Bisphenol A (BPA) is a synthetic compound utilized in industry for the production of various plastics. BPA penetrates into the environment and adversely affects living organisms. Therefore, the influence of various BPA dosages on the neurochemical characteristics of nerve fibers located in the aortic branch wall was investigated in this study utilizing a double immunofluorescence method. It was found that BPA in concentration of 0.5 mg/kg body weight/day causes a clear increase in the density of nerves within aortic branch walls immunoreactive to cocaine- and amphetamine-regulated transcript (CART), calcitonin gene-related peptide (CGRP), neuronal isoform of nitric oxide synthase (nNOS), pituitary adenylate cyclase-activating peptide (PACAP), and vasoactive intestinal polypeptide (VIP). Nerves containing galanin (GAL) and/or somatostatin (SOM) did not change when BPA was introduced into the system. Changes noted after administration of BPA at a dose of 0.05 mg/kg body weight/day were less visible and concerned fibers immunoreactive to CART, CGRP, and/or PACAP. The obtained results show that BPA affects the neurochemical coding of nerves in the aortic branch wall. These fluctuations may be the first signs of the influence of this substance on blood vessels and may also be at the root of the disturbances in the cardiovascular system.

Stem and caudex anatomy of succulent plant species

Succulent angiosperm plants are characterized by the presence of large amounts of water storage tissue as an adaptation to habitats where water is unavailable seasonally or in microhabitats where water is of limited access. In this study, I describe the anatomy of stem and caudex of ten species of succulent plants from eight plant families in the Rosids clade. There are two characteristics of wood among all species with single continuous cambium or successive cambium: 1) extensive parenchyma tissue in ray system and/or axial system; and 2) extensive thin-walled fiber tissue in the axial system. Out of ten species, five present proliferation of the parenchyma tissue in their radial system: Ceropegia africana R. Br., Momordica rostrata Zimm., Oxalis megalorrhiza Jacq., Adenia glauca Schinz and Cyphostemma juttae (Dinter & Gilg) Desc. Five species were fibrous-wood succulents: Jatropha curcas L., J. macrantha Müll. Arg., Adenium obesum (Forssk.) Roem. & Schult., Pelargonium carnosum (L.) L'Hér. and Moringa drouhardii Jum. Out of ten, one presents an axial system without visible fibers: Cyphostemma juttae (Dinter & Gilg) Desc. Despite to belong to seven different orders, the studied species show structural similarity: extensive parenchyma in the ray system and thin-walled fibers in the axial system. These results suggest multiple independent origins for the anatomical structure of succulence.

Experimental Analysis of In Situ Fenestration of Endovascular Stent-Grafts: Comparison between Needle and Laser Puncture

To evaluate the quality of in vitro fenestrations during in situ fenestration (ISF) and investigate the differences between needle and laser puncture in current stent-grafts. An in vitro study evaluated the damage created by needle ISF on stent-graft fabrics versus laser ISF. Fenestrations were made in 5 different commercially available stent-grafts, including polyester stent-grafts (Relay, Valiant and Hercules) and expanded polytetrafluoroethylene (ePTFE) stent-grafts (TAG and Ankura). Each stent-graft received fenestration by needle and laser separately, followed by gradual dilation (4 mm, 6 mm, 8 mm, and 10 mm sequentially) of noncompliant balloons. Quantitative and qualitative evaluations including fenestration diameter, area, shape and margins were conducted using light microscopy and scanning electron microscope. The primary fenestrations created by needle were slit-like with visible cut-off fibers in polyester stent-grafts and were almost circular with clear margins in ePTFE stent-grafts; those created by laser were squared or elliptical with ragged edges and burned fibers in all the stent-grafts. Fabric debris and toxic particles due to burning of the material were generated during laser-assisted fenestration. The Primary holes in polyester stent-grafts (Relay, Valiant and Hercules) by needle showed smaller area (0.05 mm2 vs. 0.22 mm2, 0.52 mm2 vs. 0.70 mm2 and 0.28 mm2 vs. 0.46 mm2; P < 0.01) and worse shape (0.93 vs. 2.46, 1.17 vs. 2.33 and 0.93 vs. 2.47; P < 0.01) than those by laser, while larger area (0.67 vs.0.43, 0.59 vs.0.45; P < 0.05), better shape (3.93 vs. 2.53, 3.90 vs. 2.93; P < 0.05) and better margin (3.83 vs. 2.47, 3.83 vs. 2.53; P < 0.05) in ePTFE stent-grafts (TAG and Ankrura). After gradual balloon dilation, the final holes showed no evident difference in maximal length, fenestration area, scores of shape and margin between the 2 ways of fenestration (P > 0.05). Ankura stent-graft showed the largest holes with best quality than the others. The primary fenestrations were different between needle and laser puncture, laser induced fabric debris and toxic particles release should be cautiously considered. The final fenestrations were similar after gradual balloon dilation.

Isolation and Characterization of Cellulose from Banana Stems using Microwave Heating

During each day of harvest, wasted banana stems are obtained in large quantities. These stems are composed mainly of 74.37% cellulose which is a very important raw material. This study aims to isolate cellulose from banana stems using liquefaction, delignification and bleaching processes with a microwave at power variations of 450, 600 and 800 W. The results showed that the highest cellulose content of 86.43% was obtained at 800 W for 14 minutes. Meanwhile, the fourier-transform infrared spectroscopy (FTIR) analysis result did not show a peak at wavenumber 1519 cm-1 which is the specific peak for lignin but showed a peak for cellulose at wavenumber 898 cm-1. Furthermore, XRD analysis of crystallinity showed a typical diffraction peak of cellulose at 22.5o with a degree of crystallinity of 56.8% while, morphological analysis with SEM showed that the sizes of the cellulose fibers produced varied, ranging from 5 to hundreds of micrometers and visible fibrillary fibers

Preliminary Study of In Vitro Three-Dimensional Skin Model Using an Ovine Collagen Type I Sponge Seeded with Co-Culture Skin Cells: Submerged versus Air-Liquid Interface Conditions.

Three-dimensional (3D) in vitro skin models have been widely used for cosmeceutical and pharmaceutical applications aiming to reduce animal use in experiment. This study investigate capability of ovine tendon collagen type I (OTC-I) sponge suitable platform for a 3D in vitro skin model using co-cultured skin cells (CC) containing human epidermal keratinocytes (HEK) and human dermal fibroblasts (HDF) under submerged (SM) and air-liquid interface (ALI) conditions. Briefly, the extracted OTC-I was freeze-dried and crosslinked with genipin (OTC-I_GNP) and carbodiimide (OTC-I_EDC). The gross appearance, physico-chemical characteristics, biocompatibility and growth profile of seeded skin cells were assessed. The light brown and white appearance for the OTC-I_GNP scaffold and other groups were observed, respectively. The OTC-I_GNP scaffold demonstrated the highest swelling ratio (~1885%) and water uptake (94.96 ± 0.14%). The Fourier transformation infrared demonstrated amide A, B and I, II and III which represent collagen type I. The microstructure of all fabricated sponges presented a similar surface roughness with the presence of visible collagen fibers and a heterogenous porous structure. The OTC-I_EDC scaffold was more toxic and showed the lowest cell attachment and proliferation as compared to other groups. The micrographic evaluation revealed that CC potentially formed the epidermal- and dermal-like layers in both SM and ALI that prominently observed with OTC-I_GNP compared to others. In conclusion, these results suggest that OTC_GNP could be used as a 3D in vitro skin model under ALI microenvironment.

Morphological Characteristics of Thymus in the Newborns in Different Climatic and Geographical Conditions of Kyrgyzstan

This paper is describing a detailed study of morphological structures and characteristics newborns thymus in different climatic and geographical conditions of Kara-Balta, Cholpon-Ata, and Bishkek in Kyrgyzstan. Anatomical structure research done on 26 thymuses of newborn corpses. Research results showed that a significant amount of thymuses consisted of lobes with very thin connective tissues between them. It is observed that the Hassall cells were usually located in the medulla part of the thymus after using the coloring by Van-Gieson’s stain visible clear elastic and collagen fibers. In addition, cell population dynamics in a unit of conditional area of cortical substance thymus lobes in newborns determined.

Esophageal mucosal innervation in functional heartburn: Closer to healthy asymptomatic subjects than to non-erosive reflux disease patients.

Mucosal innervation in non-erosive reflux disease (NERD; pathological esophageal acid exposure, normal macroscopic mucosa) is clearly distinct from that of healthy volunteers (HV) and from patients with esophagitis or Barrett's esophagus: The nerves in NERD are situated much closer to the luminal surface of the mucosa. Patients with functional heartburn (FH) have a similar symptom profile to patients with NERD and indistinguishable macroscopic appearances. However, they have physiological acid exposure and no reflux-symptom association. The aim of our study was to delineate the position of esophageal mucosal nerve fibers in patients with FH and compare it with that in NERD and HV. Distal esophageal biopsies from patients with FH were immunohistochemically stained for CGRP. CGRP-positive nerve fibers were identified, and their position relative to the lumen was determined. These results were compared to our previously published cohort of HV and NERD. Eleven patients were included in the FH group with a mean age of 46years (range 33-69); 7F:4M. Nine patients had visible nerve fibers. The location of the afferent nerve fibers in the distal esophageal mucosa (median of 22, range 10.4-28) was similar to the HV group (median 25.5) and significantly deeper than the superficial nerves seen in NERD (median 9.5). The mucosal innervation pattern in FH is more alike that of healthy individuals than that of NERD, with afferent nerves lying deep in the mucosa, away from the luminal surface. This supports the theory that heartburn in FH has a distinct nociceptive pathophysiology.

ДОСЛІДЖЕННЯ АНАТОМІЧНОЇ БУДОВИ ПІДЗЕМНИХ ОРГАНІВ РОДОВИКА ЛІКАРСЬКОГО (SANGUISORBA OFFICINALIS L. )

Мета роботи. Родовик лікарський (Sanguisorba о№ сіпаіів L.) - багаторічна трав’яниста рослина, підземні органи якої здавна використовують у медицині як в'яжучий і кровоспинний засіб. Офіційною медициною використовуються препарати родовика лікарського з кореневища з коренями. У наукових джерелах недостатньо інформації про фармакогностичне вивчення підземних органів родовика лікарського, тому метою нашої роботи було вивчити анатомічну будову, встановити і зіставити діагностичні ознаки кореневищ і коренів, зібраних восени на першому і другому роках вегетації даного виду.Матеріали і методи. Виготовлення мікропрепаратів проводили за загальноприйнятими методами. Використовували мікроскоп МС 10 (окуляри Х5, Х10, 15, об’єктиви Х10, Х40). Мікрофотографії зроблені фотокамерою Sаmsung PL50.Результати й обговорення. Кореневище. Підземна частина родовика лікарського представлена багаторічним епігеогенним кореневищем з придатковими коренями. Кореневище поступово дерев’яніє, стає пухким, порожнистим у центрі. Анатомічна будова кореневища безпучкова. Молоді однорічні кореневища вкриті темно-бурим, поздовжньо зморшкуватим корком. У особин другого року вегетації клітини корка ущільнюються, починають злущуватись. Первинна кора однорічних кореневищ представлена шарами крупноклітинної паренхіми. Ксилема і флоема паренхіматизовані, пронизані розширеними радіальними серцевинними променями. В клітинах накопичуються прості і складні крохмальні зерна, часто зустрічаються друзи. Помітно виділяється щільне кільце камбію. Провідна система представлена судинами. Механічні волокна розташовані відокремлено, невеликими ділянками поблизу судин або утворюють суцільне кільце поряд з камбієм. Серцевина з міжклітинниками, паренхімні клітини з крохмальними зернами і друзами кальцій оксалату. Корені мають вторинну будову. Корок шаруватий, кільця з коричневим або жовтуватим вмістом чергуються з кільцями світлішими або безбарвними. Зона камбію багатошарова, темніша, добре помітна. Ксилема промениста. Трахеїди пористі. Серцевинних променів багато. У клітинах наявні дрібні прості овальні та округлі крохмальні зерна, друзи та поодинокі призматичні або багатогранні кристали кальцію оксалату. У дворічних коренів зовнішній шар корка товстий, темно-коричневий, з тріщинами; чітко виділяються річні кільця ксилеми, серцевинних променів багато, волокна лубу чисельні, здерев’янілі.Висновки. Досліджено анатомічну будову підземних органів родовика лікарського, зібраних на першому і другому роках вегетації. Виявлено мікроскопічні діагностичні ознаки кореневищ і коренів.

A microfabricated platform with hydrogel arrays and on-chip strain sensing for mechanical stimulation of 3D cell-seeded hydrogels

Event Abstract Back to Event A microfabricated platform with hydrogel arrays and on-chip strain sensing for mechanical stimulation of 3D cell-seeded hydrogels Haijiao Liu1, 2*, Yu Sun1, 2 and Craig A. Simmons1, 2* 1 University of Toronto, Mechanical and Industrial Engineering, Canada 2 University of Toronto, Institute of Biomaterials and Biomedical Engineering, Canada Introduction: Cellular microenvironments present cells with multiple stimuli, including not only biochemical and matrix cues but also mechanical factors[1]. Biomaterial arrays enable systematic screening of the combined effects of microenvironmental cues on cell function[2], but these array platforms typically fail to include the effects of dynamic mechanical stimulation, which is relevant to native and engineered connective and cardiovascular tissues. To address this need, we present a deformable membrane array that enables complex mechanical loading to cells embedded in 3D hydrogel constructs and has on-chip strain sensors for continuously monitoring of the samples’ stiffness. Materials and Methods: Stretching soft hydrogels is a challenge addressed by using off-stoichiometry thiol-ene based polydimethylsiloxane (OSTE-PDMS)[3] membranes to covalently bond polyethylene glycol norbornene (PEG-NB) hydrogels, a clinically-relevant model biomaterial with tunable properties[4], via a thiol-ene reaction (Fig.1A-C). Blends of carbon nanotube (CNT) and PDMS exhibit strain-dependent resistivity[5] and are patterned as strain sensors to monitor the membrane deflection. Sensors were preconditioned to ensure reliable strain signals, then calibrated with experimentally measured membrane deflection (Fig.1D-E). Mesenchymal stromal cells (MSCs) embedded in PEG-NB were cultured and stimulated (17% max strain, 0.1 Hz, 10 hrs/day) for 11 days. The resistive strain amplitude |ΔR/R0| was used to calculate sample elastic modulus by inverse finite element analysis (Fig. 1F). To assess the 3D mechanical stimulation effect, MSCs were stained for α-smooth muscle actin (αSMA) for myofibroblast differentiation and collagen type I (Col I) for collagen production. Results and Discussion: PEG-NB gels remained firmly attached to and deformed elastically with the OSTE-PDMS membranes up to at least 40% strain under tensile stretching (Fig. 1C). The CNT sensors were able to measure the elastic modulus of non-degradable PEGNB gels with stiffnesses up to 30 kPa. Mechanically-stimulated cell-seeded PEG-NB gels stiffened during culture, as evidenced by a 20% decrease in the time-dependent |ΔR/R0| (Fig. 2A top), in comparison with less than 10% reduction in |ΔR/R0| for the control sensors without gels. This corresponded to a ~2-fold increase in the elastic modulus of the stimulated gels from ~15 to ~30 kPa (Fig. 2A bottom). Cells within the mechanically-stimulated gels were spread throughout the gel volumes and expressed αSMA with visible stress fibers, indicating myofibroblastic differentiation (Fig.2B). Abundant collagen was evident in the gel peripheries (Fig. 2C). Conclusion: MSCs embedded in PEG-NB gels and subjected to dynamic mechanical stimulation undergo myofibroblast differentiation and synthesize collagen, leading to gel stiffening. This system can be scaled up to larger arrays to enable systematic screening of 3D microenvironmental cues on cell function and tissue formation in vitro.

Soft-tissue preservation in the Middle Jurassic ammonite Cadoceras from Central Russia

The findings of fossilized ammonite soft tissues are extremely rare, so each specimen may be important for understanding the anatomy of these cephalopods. This paper deals with soft tissue fragments and imprints preserved in the rear part of the body chamber of the Middle Jurassic ammonite Cadoceras stupachenkoi from Central Russia. At the base of the body chamber of this ammonite in front of the last septum, a mantle fragment with clearly visible longitudinal fibers and imprints of the palliovisceral ligament are preserved. In front and slightly to the side of the mantle fragment, a small area with branched structures is located; probably, these structures are fragments of gills. In general, the structure of the soft tissues in the rear part of the ammonite body looks very similar to that of modern nautilids, with one exception: mantle fibers are not directed forward as observed in Nautilus, but to the mid-ventral line, probably to the ventral muscle.

Renal Denervation Increases Renal Blood Flow Variability in Conscious Rabbits

Activation of the renal nerves, as observed in multiple disease states, is known to have a profound impact on renal blood flow (RBF) and hemodynamics. However, little is known about their role in maintaining renal hemodynamics under normal resting conditions. We hypothesized that the renal nerves limited RBF variability. To test this, we instrumented 8 New Zealand White rabbits with radiotelemetry, and implanted a renal flow probe on the left kidney. Rabbits randomized to the denervation group underwent bilateral denervation by stripping the renal arteries of all visible fibers. In the innervated group a sham surgery was performed. Data were recorded in conscious rabbits resting quietly. Denervated rabbits had increased RBF (40.7 ± 4.2 mL/min vs. 62.0 ± 9.9 mL/min, p &lt; 0.05) and greater beat‐to‐beat RBF variability quantified by the standard deviation of the beat‐to‐beat RBF (2.6 ± 0.2 mL/min vs 3.7 ± 0.3 mL/min p &lt; 0.01). The increased variability persisted even after variance stabilization of the beat‐to‐beat RBF by square root transformation (0.20 ± 0.01√ (mL/min) vs 0.25 ± 0.01√(mL/min), p &lt; 0.05). Similarly, greater dispersion of the beat‐to‐beat RBF was observed in the RBF histograms of denervated rabbits compared to innervated rabbits (p &lt; 0.001). Frequency analysis revealed that the renal nerves decreased the proportion of high frequency variability (24.8 ± 3.8 % vs 38.5 ± 1.2 % of total power p &lt; 0.01). Additionally, the transfer function gain between mean arterial pressure and RBF tended to be lower in innervated rabbits compared to denervated rabbits (1.00 ± 0.25 mL/min/mmHg vs. 1.89 ± 0.35 mL/min/mmHg, p = 0.08) in the high frequency range. These data indicate that the renal nerves serve to limit fluctuations in RBF. Supported by AHA PREDOC14700045.

Campylobacter jejuni motility is required for infection of the flagellotropic bacteriophage F341.

Previous studies have identified a specific modification of the capsular polysaccharide as receptor for phages that infect Campylobacter jejuni. Using acapsular kpsM mutants of C. jejuni strains NCTC11168 and NCTC12658, we found that bacteriophage F341 infects C. jejuni independently of the capsule. In contrast, phage F341 does not infect C. jejuni NCTC11168 mutants that either lack the flagellar filaments (ΔflaAB) or that have paralyzed, i.e., nonrotating, flagella (ΔmotA and ΔflgP). Complementing flgP confirmed that phage F341 requires rotating flagella for successful infection. Furthermore, adsorption assays demonstrated that phage F341 does not adsorb to these nonmotile C. jejuni NCTC11168 mutants. Taken together, we propose that phage F341 uses the flagellum as a receptor. Phage-host interactions were investigated using fluorescence confocal and transmission electron microscopy. These data demonstrate that F341 binds to the flagellum by perpendicular attachment with visible phage tail fibers interacting directly with the flagellum. Our data are consistent with the movement of the C. jejuni flagellum being required for F341 to travel along the filament to reach the basal body of the bacterium. The initial binding to the flagellum may cause a conformational change of the phage tail that enables DNA injection after binding to a secondary receptor.