Granule Growth Research Articles

Capacitive Sensing for Monitoring Stent Patency in the Central Airway.

Central airway obstruction (CAO) is a respiratory disorder characterized by the blockage of the trachea and/or the main bronchi that can be life-threatening. Airway stenting is a palliative procedure for CAO commonly used given its efficacy. However, mucus impaction, secretion retention, and granulation tissue growth are known complications that can counteract the stent's benefits. To prevent these situations, patients are routinely brought into the hospital to check stent patency, incurring a burden for the patient and the health care system, unnecessarily when no problems are found. In this paper, we introduce a capacitive sensor embedded in a stent that can detect solid and colloidal obstructions in the stent, as such obstructions alter the capacitor's dielectric relative permittivity. In the case of colloidal obstructions (e.g., mucus), volumes as low as 0.1 ml can be detected. Given the small form factor of the sensor, it could be adapted to a variety of stent types without changing the standard bronchoscopy insertion method. The proposed system is a step forward in the development of smart airway stents that overcome the limitations of current stenting technology.Clinical Relevance- This establishes the foundation for smart stent technology to monitor stent patency as an alternative to rutinary bronchoscopies.

Spontaneous Formation of Porous Zinc in Rechargeable Zinc Batteries

The stability of Zn anodes in Ni-Zn and Zn-air batteries is dictated by the electrochemical transition between Zn and ZnO, the complexity of which has long obscured the micro-structural roots of anode failures such as shape changes, passivation, and dendrite formation. Here we reveal that in this phase transition evolves porous Zn, a structure that underpins the rechargeability of the anode. At sequential stages of charging and discharging cycles, we retrieved over one hundred anodes initially made of ZnO particles. At their cross-sections, we observe the progressive, spontaneous evolution of connected curvy Zn ligaments, explained by the continuum percolation theory and structural self-organization. The growth and consumption of ZnO spikes on the porous structure become a steady state until being upended by the growth of large Zn granules via the long-range transport of zincate. More conductive additive promotes the formation of porous Zn, which improves the cycle life to 230 cycles at 30% utilization of the zinc mass, among the best reported for an alkaline Zn anode. The work underlines the importance of micro-structural evolution for the fulfillment of cheap, safe energy storage by Zn.

Clinical Study on the Efficacy of Silver Ion Dressing Combined with Prontosan Gel Dressing in the Treatment of Diabetic Foot Ulcers and the Effect on Serum Inflammatory Factors.

Diabetic foot ulcers (DFUs) have a high disability rate and have a great impact on patients and society, and the search for effective and economical treatment options is a major clinical concern. In this study, 112 patients with DFU admitted to two hospitals from October 2018 to November 2020 were randomly divided into 56 cases each in the single group treated with Prontosan gel dressing and the joint group treated on silver ion dressing combined with Prontosan gel dressing. Both groups of patients were evaluated for efficacy after 30 days of treatment. The number of days for debridement, granulation tissue growth time, epithelial tissue formation time, and wound healing time were observed and recorded in both groups. The trauma area, visual analogue score (VAS), and levels of inflammatory factors such as vascular endothelial adhesion molecule-1 (VCAM-1), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and C-reactive protein (CRP) were recorded before and after treatment in both groups. The occurrence of adverse reactions such as edema, fever, infection, and rash during treatment was recorded in both groups for safety assessment. Comparison of the abovementioned data showed that the clinical efficacy of the joint group was significantly higher than that of the single group. The number of days to clear wounds, granulation tissue growth time, epithelial tissue formation time, and wound healing time were significantly lower in the joint group than in the single group. The trauma area, VAS score, VCAM-1, IL-6, TNF-α, and CRP levels decreased in both groups after treatment compared with the pretreatment levels, with the joint group being lower than the single group. The results also showed that the difference in the overall incidence of adverse reactions between the two groups was not statistically significant, and the incidence was low and transient. In addition to the usual treatment regimen of blood glucose control and improvement of microcirculation for patients with DFU, combined treatment with silver ionomer dressings and Prontosan gel dressings can promote ulcer healing and improve foot wound regression. It has a stronger antibacterial effect and can more effectively reduce the inflammatory response of the ulcerated surface with fewer adverse effects, making it an effective and safe method for the treatment of DFU, and has implications for promotion.

Topical Administration of Heat-Killed Enterococcus faecalis Strain KH2 Promotes Re-Epithelialization and Granulation Tissue Formation during Skin Wound-Healing.

Lactic acid bacteria (LAB) are known to have beneficial effects on immune responses when they are orally administered as bacterial products. Although the beneficial effects of LAB have been reported for the genera Lactobacillus and Lactococcus, little has been uncovered on the effects of the genus Enterococcus on skin wound-healing. In this study, we aimed to clarify the effect of heat-killed Enterococcus faecalis KH2 (heat-killed KH2) strain on the wound-healing process and to evaluate the therapeutic potential in chronic skin wounds. We analyzed percent wound closure, re-epithelialization, and granulation area, and cytokine and growth factor production. We found that heat-killed KH2 contributed to the acceleration of re-epithelialization and the formation of granulation tissue by inducing tumor necrosis factor-α, interleukin-6, basic fibroblast growth factor, transforming growth factor (TGF)-β1, and vascular endothelial growth factor production. In addition, heat-killed KH2 also improved wound closure, which was accompanied by the increased production of TGF-β1 in diabetic mice. Topical administration of heat-killed KH2 might have therapeutic potential for the treatment of chronic skin wounds in diabetes mellitus. In the present study, we concluded that heat-killed KH2 promoted skin wound-healing through the formation of granulation tissues and the production of inflammatory cytokines and growth factors.

Successful Management of Complex Pediatric and Neonatal Wounds With Methylene Blue and Gentian Violet Foam Dressings

Topical antimicrobial treatment of wounds in pediatric, and especially neonatal, patients can be challenging due to increased systemic absorption, damaging inflammatory cytokines, and oxygen radicals released by bacterial death. A product combining all wound bed preparation principles is desired. Methylene blue and gentian violet (MB/GV) foam dressings can keep wound beds moist, decrease ongoing inflammation, provide antibacterial coverage, and promote healthy wound edges. This article examines the use of MB/GV antibacterial foams in pediatric patients. Cases included infants with giant omphalocele epidermal stripping, dehisced abdominal wounds, peristomal dermatitis, and peripheral intravenous extravasations and adolescents with stage 4 pressure injuries. The treatment goals were to optimize the wound bed through debridement, elimination of bioburden, providing moisture balance, and enhancement of granulation tissue growth. Eight patients (6 infants and 2 adolescents) received MB/GV foam dressings every 2 to 3 days along with standard of care (SOC) management. Effective debridement, bioburden elimination, moisture balance, and edge enhancement were achieved in all wounds. All wound beds were well-prepared to receive other SOC products as needed. Three cases were considered for negative pressure wound therapy (NPWT), but NPWT was not used because of challenging clinical characteristics and wound locations. Instead, MB/GV polyvinyl alcohol foam provided capillary wicking action that enhanced wound closure without NPWT. No side effects were observed. Methylene blue and gentian violet foam dressings appear to be a safe clinical option for antibacterial coverage, moisture management, and debridement in neonatal and pediatric patients.

Diagnostic performance of digital tomosynthesis to evaluate silicone airway stents and related complications.

BackgroundDigital tomosynthesis (DTS) is an imaging technique with benefits in reconstructing sequential cross-sectional images. We evaluated the diagnostic performance of DTS for silicone airway stents and stent-related complications in patients who underwent bronchoscopic intervention.MethodsThis retrospective study included patients who underwent bronchoscopic intervention after chest radiography (CXR) and DTS examinations from September 2013 to August 2020. The interval between CXR, DTS, and bronchoscopic intervention was a maximum of 10 days. CXR and DTS images were evaluated using a bronchoscopic view as a reference. We calculated the sensitivity, specificity, accuracy, positive predictive value, and negative predictive value for assessing the diagnostic performance.ResultsThe total CXR, DTS, and bronchoscopic intervention-matching datasets comprised 213 cases from 119 patients and, silicone stents were present in 167 of them. The ability of DTS to detect silicone stents was better than that of CXR (sensitivity, 92.8% vs. 71.3%, P<0.001). Of the 167 cases with silicone stents, 53 experienced stent migration and 121 experienced stent obstructions due to granulation tissue or fibrosis. The sensitivity for detecting stent migration was also higher with DTS than with CXR (45.3% vs. 24.5%, P=0.025). The sensitivity for detecting the stent obstruction was better with DTS than with CXR (64.5% vs. 19.0%, P<0.001).ConclusionsDTS was more sensitive and accurate in revealing silicone airway stents and silicone stent-related complications than CXR. However, there were limitations in confirming stent migration and obstruction with DTS due to granulation tissue growth and fibrosis.

Anaerobic granulation of single culture Clostridium beijerinckii

This study utilizes Clostridium beijerinckii P260, an anaerobic bacterium capable of acetone-butanol-ethanol (ABE) production, as model bacteria to test the hypothesis that single culture anaerobic granulation can be achieved in accordance with the biogranulation theory developed from the mixed culture studies. After four months of cultivation, C. beijerinckii granules formed under the selection pressure of a selective settling velocity at 9.0 m h−1 in a sequential batch reactor (SBR). These C. beijerinckii granules possess excellent settleability and exceptionally high cell and enzyme concentrations, which demonstrate promising potential in the application for high-rate fermentation and separation of value-added products. However, C. beijerinckii granules only accounted for 25% of the cell mass in the SBR, leaving the rest 75% still in the form of planktonic cells, which indicates an incomplete anaerobic granulation. The lack of ideal feast and famine conditions in the cyclic SBR operation was regarded as the reason. Future research should focus on the optimization of the bioreactor operation to create optimal conditions for inducing the phenotype switch from planktonic to granulated growth mode.

Impact of feedwater protein contents on calcium phosphate mineralization in anaerobic digesters

Calcium phosphate (CaP) mineralization and accumulation in anaerobic digesters represent an attractive approach to recovery phosphorus (P) from wastewater. Previous studies demonstrated that under certain anaerobic digestion conditions, favorable localized environment can be developed to facilitate CaP granule growth. However, factors that trigger the CaP nucleation in anaerobic reactors have not been elucidated. In this study, to examine the driving forces in the microenvironment for the CaP nucleation, two laboratory upflow anaerobic sludge blanket (UASB) reactors fed with two types of synthetic wastewater were operated under mesophilic conditions. The feed of one reactor (G reactor) had glucose as the sole carbon source, and the feed of the other reactor (G+B reactor) had glucose (60% chemical oxygen demand (COD)) and bovine serum albumin (BSA, 40% COD) as the combined carbon sources. The results showed that P and Ca removals were only observed in the G+B reactor. The main difference between the two reactors was the elevated pH in the G+B reactor, which may be attributed to the degradation of amino acids. The elevated pH caused the deprotonation of the negatively charged functional groups in the sludge, creating available active surfaces for Ca2+ complexation. The high availability of OH- and the enriched Ca in the G+B reactor built a favorable microenvironment to overcome the activation energy barriers hindering the CaP nucleation. The stabilized CaP mineralization largely depended on the well-established microbial community, where the efficient hydrogenotrophic methanogens and syntrophic acetogens may maintain a stabilized pH environment to prevent the dissociation of CaP minerals.

CBM20CP, a novel functional protein of starch metabolism in green algae.

Ostreococcus tauri is a picoalga that contains a small and compact genome, which resembles that of higher plants in the multiplicity of enzymes involved in starch synthesis (ADP-glucose pyrophosphorylase, ADPGlc PPase; granule bound starch synthase, GBSS; starch synthases, SSI, SSII, SSIII; and starch branching enzyme, SBE, between others), except starch synthase IV (SSIV). Although its genome is fully sequenced, there are still many genes and proteins to which no function was assigned. Here, we identify the OT_ostta06g01880 gene that encodes CBM20CP, a plastidial protein which contains a central carbohydrate binding domain of the CBM20 family, and a coiled coil domain at the C-terminus that lacks catalytic activity. We demonstrate that CBM20CP has the ability to bind starch, amylose and amylopectin with different affinities. Furthermore, this protein interacts with OsttaSSIII-B, increasing its binding to starch granules, its catalytic efficiency and promoting granule growth. The results allow us to postulate a functional role for CBM20CP in starch metabolism in green algae. KEY MESSAGE: CBM20CP, a plastidial protein that has a modular structure but lacks catalytic activity, regulates the synthesis of starch in Ostreococcus tauri.

Determining the main regularities in the process of mineral fertilizer granule encapsulation in the fluidized bed apparatus

This paper has substantiated the expediency and prospects of obtaining organomineral fertilizers by encapsulating mineral granules with an organic suspension in fluidized bed apparatuses. An overview of existing approaches to the mathematical description of the kinetics of granule growth in granulation processes in fluidized bed apparatuses is presented. A mathematical model of the kinetics of the formation of a hard shell around granules in a fluidized bed has been built. It shows that the kinetics depend on the size of the retour particles, the specific flow rate of the suspension, the density of the suspension and granules, and the time of the process. Equations have been derived for determining the thickness of the hard shell and the specific flow rate of the suspension for individual granulation stages in a multi-stage granulator of the fluidized layer. Analytically, graphical dependences were built, which showed an increase in the thickness of the hard shell due to an increase in the specific flow rate of the suspension, the diameter of the retour particles, and the time of the encapsulation process. The equations make it possible to determine the rational regime and technological parameters of the encapsulation process in order to obtain a coating of the predefined thickness at the surface of the granules. This ensures that a quality product is obtained, with a granulometric composition in a narrower range of particle size. To obtain granules of 2.5–4 mm in size, it is necessary to carry out the process in three- or four-stage granulators of the fluidized bed at specific suspension consumption of (10–20)∙10-4 kg/(kg∙s.). It is shown that with uniform growing of granules with a constant increase in the thickness of the shell in multistage granulators, the suspension consumption decreases by 2‒3 times from the first stage to the subsequent ones. This approach reduces the operating and energy costs of the process.

Partitioning of nutrient removal contribution between granules and flocs in a hybrid granular activated sludge system

Sludge granulation in continuous-flow systems is an emerging technology to intensify existing activated sludge infrastructure for nutrient removal. In these systems, the nutrient removal contributions and partitioning of microbial functions between granules and flocs can offer insights into process implementations. To this end, a reactor system that simulates the continuous-flow environment using an equal amount of initial granule and floc biomass was investigated. The two operational strategies for maintaining granule growth in the continuous-flow system were (a) the higher solids retention time (SRT) for the granules versus flocs, as well as (b) selective feeding of carbon to the granules. The SRT of the large granule fractions (>425 µm, LG) and floc/small granule fractions (<425 µm, FSG) were controlled at 20 and 2.7–6.0 days, respectively. Long term operation of the hybrid granule/floc system achieved high PO43- and NH4+ removal efficiencies. Higher polyphosphate-accumulating organisms (PAO) activity was observed in the FSG than LG, while ammonia-oxidizing bacteria (AOB) activities were similar in the two biomass fractions. Nitrite shunt was observed in the FSG, possibly due to out-competition by the high NOB activity in LG. More importantly, washing out the FSG caused a reduction in LG's AOB and PAO activity, indicating a possible dependency of LG on FSG for maintaining its nutrient removal capacity. Our findings highlighted the partitioning and potential competition/cooperation of key microbial functional groups between LG and FSG, facilitating nutrient removal in a hybrid granular activated sludge system, as well as implications for practical application of the treatment platform.

The Effects of Mycophenolate on the Formation of Granulation Tissue Post-operatively in Canine Tracheal Stent Patients (2014-2020).

Objectives: To determine if mycophenolate mofetil reduces the incidence and severity of granulation tissue in-growth in canine tracheal stent patients.Study design: Randomized clinical trial.Animals: 111 dogs from the hospital population.Methods: Client-owned dogs that received an endoluminal self-expanding tracheal stent for canine tracheal collapse between 2014 and 2020 were randomly assigned into one of two treatment groups. Control group medication protocol consisted of prednisone 0.5 mg/kg PO BID/SID/EOD × 30 days, hydrocodone 0.25 mg/kg PO TID × 30 days, and cefovecin 8 mg/kg SQ post-placement. Mycophenolate group medication protocol was identical to the control group medication protocol with the addition of mycophenolate mofetil 10 mg/kg PO BID × 30 days, SID for life. Recheck tracheoscopy was performed at 1, 3, and 6 months post-stent placement. Presence and severity of granulation tissue were determined by tracheoscopy and were recorded as a percentage of tracheal lumen obstruction by blinded evaluators (none present, <25%, >25–50%, and >50%).Results: At none of the three time points was there a statistically significant difference in grade between controls and those receiving mycophenolate (p = 0.467, p = 0.330, and p = 0.410).Conclusions and Clinical Significance: Our results suggest that mycophenolate can be safely given to these patients but do not support that its administration will reduce the incidence and severity of granulation tissue. Although a difference was observed in the severity of granulation tissue between the two groups, loss to follow-up may have influenced conclusions. A larger study would be warranted to further evaluate the effect of mycophenolate on the development of granulation tissue.

Application Experience of Moist Wound Healing Theory Combined with Modern New Dressings in the Treatment of Pressure Ulcers

Objective?Research on the effect of moist wound healing theory in a combination with modern new dressingtreatment in patients diagnosed with pressure ulcers. Method: Selected 30 patients with pressure ulcers from our hospital, which is Shandong Tai’an Municipal Hospital, from January 2019 to January 2021 were divided into experimental group (15 cases, treated with moist wound healing theory combined with modern new dressings) and control group (15 cases, applied conventional treatments). The treatment effect, time of wound edema subsidence, wound healing time, number of dressing changes, granulation tissue growth time, and diameter reduction time were compared between the two groups. Results: The total effective rate of the experimental group (93.33%, 14/15) was higher than that of the control group (53.33%, 8/15), P&lt;0.05; the time to subsidence of wound edema in the experimental group was (3.11±0.22), and the time for wound healing was (12.78±0.45), the number of dressing changes (7.13±0.34) times, the growth time of granulation tissue (5.43±2.22), the diameter reduction time (6.25±3.75), compared with the control group, P&lt;0.05. Conclusion?In the clinical treatment of patients diagnosed with pressure ulcers, the effective combination of moist healing theory and modern new dressing therapy has significant effects, whereby it speeds up the healing process of the pressure ulcers, and it is proven to be worthy to be promoted for usage.

A novel function for Rab1 and Rab11 during secretory granule maturation.

Regulated exocytosis is an essential process whereby specific cargo proteins are secreted in a stimulus-dependent manner. Cargo-containing secretory granules are synthesized in the trans-Golgi network (TGN); after budding from the TGN, granules undergo modifications, including an increase in size. These changes occur during a poorly understood process called secretory granule maturation. Here, we leverage the Drosophila larval salivary glands as a model to characterize a novel role for Rab GTPases during granule maturation. We find that secretory granules increase in size ∼300-fold between biogenesis and release, and loss of Rab1 or Rab11 reduces granule size. Surprisingly, we find that Rab1 and Rab11 localize to secretory granule membranes. Rab11 associates with granule membranes throughout maturation, and Rab11 recruits Rab1. In turn, Rab1 associates specifically with immature granules and drives granule growth. In addition to roles in granule growth, both Rab1 and Rab11 appear to have additional functions during exocytosis; Rab11 function is necessary for exocytosis, while the presence of Rab1 on immature granules may prevent precocious exocytosis. Overall, these results highlight a new role for Rab GTPases in secretory granule maturation.

Three-dimensional label-free visualization and quantification of polyhydroxyalkanoates in individual bacterial cell in its native state

Polyhydroxyalkanoates (PHAs) are biodegradable polyesters that are intracellularly accumulated as distinct insoluble granules by various microorganisms. PHAs have attracted much attention as sustainable substitutes for petroleum-based plastics. However, the formation of PHA granules and their characteristics, such as localization, volume, weight, and density of granules, in an individual live bacterial cell are not well understood. Here, we report the results of three-dimensional (3D) quantitative label-free analysis of PHA granules in individual live bacterial cells through measuring the refractive index distributions by optical diffraction tomography (ODT). The formation and growth of PHA granules in the cells of Cupriavidus necator, the best-studied native PHA producer, and recombinant Escherichia coli harboring C. necator poly(3-hydroxybutyrate) (PHB) biosynthesis pathway are comparatively examined. Through the statistical ODT analyses of the bacterial cells, the distinctive characteristics for density and localization of PHB granules in vivo could be observed. The PHB granules in recombinant E. coli show higher density and localization polarity compared with those of C. necator, indicating that polymer chains are more densely packed and granules tend to be located at the cell poles, respectively. The cells were investigated in more detail through real-time 3D analyses, showing how differently PHA granules are processed in relation to the cell division process in native and nonnative PHA-producing strains. We also show that PHA granule-associated protein PhaM of C. necator plays a key role in making these differences between C. necator and recombinant E. coli strains. This study provides spatiotemporal insights into PHA accumulation inside the native and recombinant bacterial cells.

Efficacy analysis of antibiotic bone cement in treating infectious wound of lower extremity

To discuss the clinical effect of antibiotic bone cement in the treatment of infectious wound of lower extremity. From January 2016 to January 2019, 28 patients who had infection wounds of lower extremity were treated by antibiotic bone cement, including 21 males and 7 females with age of 34 to 76 (53.8±16.5) years old. The wound area after the initial debridement was 4 cm×3 cm to 12 cm×8 cm. All patients were treated with the antibiotic bone cement, when infection was controlled and fresh granulation tissue grew on the wound surface, local sutures or skin grafts were performed. The changes of white blood cell (WBC), erythrocyte sedimentation rate(ESR), C reactive protein(CRP) and positive rate of bacterial culture of wound secretions were recorded andcompared before and after 2 weeks of the operation. The healing time, recurrence rate and complications of fresh granulation on wound surface were calculated. All patients were followed up for 3 to 6(4.3±1.2) months. After the recurrence of diabetic foot wound infection, 3 patients presented different degree of rupture, and the remaining patients had good wound healing. No serious complications such as aggravation of infection and amputation occurred. The WBC, ESR and CRP of the patients were decreased significantly after operation compared with that before operation (9.1±1.2)×109/L vs. (11.4±2.2)×109/L, (23.5±7.6) mm/ h vs. (57.1±14.9) mg/L, (44.2±13.1) mg/L vs. (89.2±26.7) mg/L (P<0.05). The formation time of fresh granulation on the wound surface was 12 to 21(15.6±3.2) days. The antibiotic bone cement can control infection of lower extremity wound effectively, promote the growth of fresh granulation tissue and wound healing.

Novel LOTUS-domain proteins are organizational hubs that recruit C. elegans Vasa to germ granules.

We describe MIP-1 and MIP-2, novel paralogous C. elegans germ granule components that interact with the intrinsically disordered MEG-3 protein. These proteins promote P granule condensation, form granules independently of MEG-3 in the postembryonic germ line, and balance each other in regulating P granule growth and localization. MIP-1 and MIP-2 each contain two LOTUS domains and intrinsically disordered regions and form homo- and heterodimers. They bind and anchor the Vasa homolog GLH-1 within P granules and are jointly required for coalescence of MEG-3, GLH-1, and PGL proteins. Animals lacking MIP-1 and MIP-2 show temperature-sensitive embryonic lethality, sterility, and mortal germ lines. Germline phenotypes include defects in stem cell self-renewal, meiotic progression, and gamete differentiation. We propose that these proteins serve as scaffolds and organizing centers for ribonucleoprotein networks within P granules that help recruit and balance essential RNA processing machinery to regulate key developmental transitions in the germ line.

Role of Topical Papaya Application in Debridement of Deep Burn Wounds

Objective: To study the role of topical papaya application in managing deep burn wounds in terms of proteolytic enzymatic debridement for wound bed preparation.Material and Methods: This was a descriptive study carried out at Rawalian burn centre holy family hospital Pakistan from 12-10-2019 to 11-1-2020 over a period of 03 months. A total of 30 patients were included in the study (n=30). A convenient non-probability sampling technique was used for allocating patients to the study after getting written informed consent. For patients included in the study, papaya dressing was used for debridement and wound bed preparation of deep burn wounds.Results: There were 19 (63.3%) female and 11 (36.7%) male patients. The age range of patients was 10y to 50y with a mean of 28 years and SD ± 8.06 Patients included in the study had TBSA ranging from 10% to 35% with a mean of 19.8% and SD ± 6.82%. On average 7 dressings (Range 5-7) were required to achieve pink healthy granulation tissue. Out of total 30 patients (n=30) included in the study, good healing with the production of pink granulation was seen in 27 patients (81%) while in the rest of the 03 patients minor surgical debridement was required to achieve the pink granulation tissue bed for skin graft.Conclusion: Based on the results of this study it can be concluded that Papaya is an effective, safe, and rapid enzymatic proteolytic debriding agent of plant origin for deep burn wounds which promotes the growth of pink healthy granulation tissue with a minimal number of dressings. This granulation tissue readily accepts split-thickness skin graft.

Morphological Changes of the Ureter in Patients with Ureterolithiasis Depending on the Duration of Clinical Manifestations

Urolithiasis (URL) is a common urological disease that often appears in the population, has a high recurrent rate and a significant impact on the social status of the population. Almost half of patients with URL disease are people with ureteric stones, 95% of which have secondary genesis. The main methods of treatment of such patients are extracorporeal shock-wave lithotripsy (ESWL) and ureterolithotripsy (URS). It is important in these cases to determine morphological changes (inflammation, edema, sclerosis, necrosis, etc.) that appear in the ureter in the placement of the stone and may reduce the effectiveness of minimally invasive treatment or/and removal of fragments during URS. The objective: studying morphological changes of the ureter wall in patients with ureterolithiasis in the zone of the calculus in dependence of the duration of clinical manifestations. Materials and methods. We have studied histological changes of the ureter wall in the location of the stone in patients with ureterolithiasis. We explored the ureter wall in patients depending on duration of typical manifestations of ureterolithiasis, which were 7-en days long, 30 days, and more than 2 months. Results. If the stone in the ureter is up to 7 days, it does not cause significant microscopic changes of the ureter wall. If the stone been in the ureter during 1 month, more significant morphological changes are determined with desquamation of the urothelium, edema and inflammatory changes in the submucosal membrane. In case of the duration of the calculi in the ureter is more than 2 months, we noted the exfoliation of the urothelium with the denudation of the basement membrane. In the submucosal layer there is an edema, diffuse disorganization of connective tissue fibers, fragments of growth of granulation tissue and dense connective tissue in the form of separate layers. Conclusion. With increasing duration of the disease in the wall of the ureter increases the manifestations of inflammatory, sclerotic and necrotic changes. Such changes have a direct impact on the quality of visualization of the calculus during endoscopic interventions, the rate of fragmentation and extraction (elimination) of fragments, as a consequence, increase the overall duration of the operation and the risk of intra- and postoperative complications.

Enhancing stability of aerobic granules by microbial selection pressure using height-adjustable influent strategy

Optimizing granules size distribution is critical for both reactor performance and stability. In this research, an optimal size range of 1800 to 3000 μm was proposed regarding mass transfer and granules stability based on granules developed at DO around 8.0 mg L−1 with the feed COD:N:P at 100:5:1. A height-adjustable influent strategy was applied to facilitate the nutrient storage of granules at optimum size range via microbial selective pressure. Results suggested insufficient hydraulic shear stress led to overgrowth of granules size. High abundance of filamentous bacteria (Thiothrix sp.) was observed in oversized granules, which detached and affected the remaining granules, resulting in severe sludge bulking. Strong hydraulic shear stress suppressed uncontrolled growth of granules. However, fewer abundance of simultaneous nitrification and denitrification (SND) bacterium was acquired, which led to unfavored SND effect and total nitrogen (TN) removal efficiency. The height-adjustable influent strategy facilitated the poly-β-hydroxybutyrate (PHB) storage of granules at optimum size range, while limiting the overgrowth of granules size. Additionally, more than 87.51% of total granules situated in optimal sizes range, which led to higher abundance of SND bacterium and higher TN removal efficiency.