The mean decrease from baseline was 23%. BCVA before surgery was 0.38 ± 0.30, and that at the end of the follow-up period improved to 0.47 ± 0.37, MD = 0.09, 95% CI: 0.04, 0.13; p < 0.001. Additional procedures (fluorouracil injection and bleb needling) were performed in 11/72 patients (15%). Further glaucoma surgery was necessary for 23.9% of the patients. XEN Gel Stent implantation is both safe and reasonably effective for lowering IOP in operated uncontrolled glaucoma patients.This study aimed to analyze the surgical and refractive outcomes of XEN glaucoma implant , a minimally invasive surgical device for the treatment of operated uncontrolled glaucoma. Eyes that received XEN Gel Stent placement from December 2014 to October 2019 were retrospectively investigated. Intraocular pressure (IOP) change, best-corrected visual acuity (BCVA), change in glaucoma medications, frequency of slit lamp revision procedures, and frequency of secondary glaucoma surgeries were the primary outcomes. Seventy-two eyes of 72 subjects were included in the study: 32 (44%) men and 40 (56%) women. The follow-up period ranged from 1 to 50 months . The mean IOP before surgery was 24.82 ± 8.03 mmHg and decreased to 17.45 ± 5.84 mmHg at the end of the study (mean difference [MD] = −7.48, 95% confidence interval [CI]: −10.04, −4.93;  Glaucoma remains the second leading cause of blindness worldwide , and theIn cases of operated uncontrolled glaucoma, use of glaucoma drainage devices (GDD) is often an interesting option. Their effectiveness is comparable to trabeculectomy; however, they present a relatively high risk of complications such as anterior chamber shallowing, choroidal detachment, filtering bleb leakage, blood in the anterior chamber, chronic corneal endothelial loss, hypotony, and macular edema ,6. In adμm  was designed based on the Hagen–Poiseuille law; depending on the length and cross-section, these devices have pressure differences along the implant  men and 40 [56%] women). The mean age of patients at the time of surgery was 59.51 ± 18.22 years . The duration of the subjects' glaucoma ranged from 12 months to 56 years . The mean follow-up period was 26.87 ± 15.33 months . Twenty-five patients (35%) had POAG, 12 (17%) had PXG, 8 (11%) had glaucoma associated with Axenfeld–Rieger syndrome or Cogan syndrome, 7 (10%) had silicone oil-induced glaucoma after vitrectomy, 6 (8%) had NG, 4 (5%) had UG, 3 (4%) had closed-angle glaucoma, 3 (4%) had secondary TG, 3 (4.5%) had secondary pigmentary glaucoma, and 1 (1.5%) had glaucoma after choroidal melanoma treatment with plaque brachytherapy. Ten patients underwent combined XEN implantation and phacoemulsification, while 62 received only XEN implantation.The median number of prior surgeries performed was 1 . The prior treatments performed are shown in p < 0.001). The mean decrease from baseline was 23% . The Kaplan–Meier cumulative incidence of qualified success was 59.4% after 24 months , while the cumulative incidence of complete success after 2 years of observation was 13.4% , while an increase was observed in 34/59 subjects (58%). The cases of decrease in BCVA were caused by posterior capsulae opacification (6 subjects—10%), development of AMD (3 subjects—5%), and progression of glaucomatous neuropathy (3 subjects—5%). On the other hand, the decrease in IOP level at the end of the study, relative to the baseline value, occurred in 49/64 subjects (77%); an increase in IOP was noted in 10/64 eyes (16%). A decrease in IOP equal to or greater than 20% occurred in 9/64 eyes (14.1%), representing 18% (9/49) of all eyes with a decrease in IOP. A final IOP level of less than 15 mmHg affected 31/64 (48%) eyes.Visual Field of the mean defect (MD) before surgery was −19.0 ± 5.1. At the end of follow-up, stabilization was observed in 63.1% of the patients. Progression was observed in 36.9% of the patients.Massage was recommended to 13/72 (18%) people, and needling was performed in 43/64 patients (67%); the median number of procedures per patient was 2 (interquartile range [IQR]: 1.5–3), with a range of 1 to 12. Subconjunctival 5-FU injection was required in 14/72 (19%) patients. The median number of patients who took medication before surgery was 4 (IQR: 3–5), with a range of 1 to 5, while the median number of patients who took medication after surgery was 2 (IQR: 1–4). The first drug was introduced after 49.5 days postoperatively  Figures 2, and reoThe reoperated patients (11 eyes) had the following procedures: implantation of a second XEN in 6 and trabeculectomy in 3, and 2 eyes had bleb revision after XEN implantation. Two of these eyes underwent 2 subsequent procedures: the first one had a second XEN implanted 2 months after the procedure and trabeculectomy after another 10 months, and the second one underwent trabeculectomy 4 months after the procedure and implantation of a second XEN implant after another 7 months.The XEN® Gel stent implant is gaining more and more popularity among glaucoma surgeons as a natural alternative to trabeculectomy. To the best of our knowledge, only few clinical trials have evaluated its use in OUG cases. This retrospective analysis confirms that XEN implantation decreases both IOP and the number of antiglaucoma medications in patients with this type of glaucoma, with a relatively favourable safety profile.Grover et al.  in theirp < 0.005), when compared with that in our group, in which it was 4 before the surgery (IQR: 3–5) and 2 after the surgery (IQR: 1–4). The surgical success was higher at 62%, and the rate of complete and qualified success was 64% in Tan et al.'s study. All the previous studies have reported a more favourable hypotensive effect compared to our results; however, these studies had half the duration of the follow-up period as that in this study. In addition, given the stage of glaucoma in our study group, the target IOP was set at a relatively low level (15 mmHg), in contrast to other investigations, where an IOP of 18 mmHg was the criterion for surgical success.In the study, Tan et al.  presenteThis study has several limitations. First, it was a retrospective study, and assessments of patients, including IOP monitoring, were not masked and consequently subject to observer bias. A retrospective study uses existing data that have been recorded for reasons other than research and is generally considered inferior to prospective studies. Second, the study design lacked randomization and involved a probable selection bias. Third, inconsistent follow-up visits could have resulted in missed data points. Loss of statistical significance is a potential impact of loss to follow-up. Fourth, our study describes a group of cases that received an unusual treatment. However, based on our knowledge, this is the only study involving patients with a history of 1–5 antiglaucoma surgeries with a long-term follow-up period. It would be difficult to select a group for comparison with this material. Fifth, our study group was characterized by extremely diverse cases and different mechanisms of glaucoma in different patients. Finally, our study focused only on the Caucasian population. While this may be a study limitation on one hand, a homogeneous population is also advantageous as it allows the study of a specific ethnic group.Our study has shown the mean decrease in IOP after XEN® Gel stent implantation of 23% in comparison to baseline. Postoperative IOP increase and the need for reoperation were the most common complications after surgery over a long-term follow-up period. To sum up, the applied surgery appears to show promising results in patients with OUG, owing to its minimal invasiveness. Pharmacoeconomic and quality-of-life studies in different groups of glaucoma patients are necessary to present this treatment method to patients as an alternative to trabeculectomy. As glaucoma remains the second most common cause of blindness, this study is clinically meaningful because it provides a better solution to the problem.


Boys in the CG consumed significantly more calcium (851.8 vs. 432 p = 0.0006), phosphorus (1024.3 vs. 1357.5 p = 0.0431), lactose (11.6 vs. 6.1 p = 0.0016), and riboflavin (1.7 vs. 1.3 p = 0.0123) compared to boys with IBD. Dietician care should therefore be mandatorily provided alongside outpatient care. Based on our results, we suggest that supplementation with the selected components be considered.Inflammatory bowel disease (IBD) includes Crohn’s disease (CD) and ulcerative colitis (UC). The prevalence of both in pediatric populations has been constantly increasing. This study aimed to analyze the diet of adolescent patients with IBD in comparison to healthy controls and the current dietary standards for the Polish population to further their optimal supplementation regimen. The study group consisted of 53 patients (21 girls and 32 boys) with IBD  at a mean age of 15.4 ± 2.4 and 14.7 ± 2.2, years for girls and boys, respectively. The control group (CG) consisted of 20 patients, and 72 h of recall diaries on nutrition were collected. The nutritional data were analyzed in the Dieta 6D dietary program. When compared to Polish dietary standards, the largest differences girls with IBD and boys with IBD were found for the intake of energy (61.9 and 71.9%), iodine (61.9 and 62.6%), folates (76.2 and 87.5%), vitamin D (100 and 96.9%), potassium (61.9 and 59.4%), and calcium (85.7 and 93.8%). The overconsumption of saturated fatty acids (SFA) (61.9 and 56.3%) and sodium (76.2 and 90.6%) in girls and boys, respectively, was noted. In relation to girls with CG, girls with IBD showed a significantly higher intake of energy (1751. 3 vs. 1558.6  Inflammatory bowel disease (IBD) includes Crohn’s disease (CD) and Ulcerative Colitis (UC). The disease is characterized by chronic non-infectious inflammation of the gastrointestinal tract (GT) . UC mainCurrently, a relevant increase in the prevalence of IBD in children has been noted . The groThe pathophysiology of IBD is still not completely understood. It has been suggested that the disease occurs in genetically susceptible individuals as a result of an uncontrolled immune system response to a trigger factor . Other fAccording to the recommendations of the European Society for Clinical Nutrition and Metabolism (ESPEN), nutritional care is a key component of therapy for patients with IBD. CD patients especially are at a higher risk of developing malnutrition due to the possible involvement of each gastrointestinal tract segment. Moreover, there are no specific nutritional guidelines or recommendations regarding nutrition for individuals with IBD. The diet is usually based on the patient’s individual condition .With chronic inflammation and impaired absorption, the risk of deficiencies in micro and macro dietary components increases. Malabsorption is correlated with mucosal function abnormalities such as impaired transport across the epithelium and reduced intestinal barrier integrity . IBD patProper nutrition is particularly important for the proper development of youth. Identifying inappropriate eating habits at an early age can reduce the risk of their repetition into adulthood. An adequate dietary intake of nutrients supports the healing process and an inadequately managed diet can become highly deficient and lead to impaired physical, intellectual, and mental development. In addition, as mentioned above, abnormal attitudes toward eating can negatively impact social competency. Therefore, the aim of this study was to assess the dietary intake of energy, macro-, and micronutrients by adolescents with IBD compared to Polish reference standards and control group (CG) intake. The study also aimed to identify possible nutritional deficiencies in patients with IBD and to identify components for which supplementation should be considered .A pilot study of ours on IBD and celiac disease has found no significant differences in the nutritional habits between CD and UC. In contrast, differences in nutrition intake between IBD and celiac disease have been shown . Thus, tThe study presents a single-center analysis of the diets of adolescent patients with IBD. The study group included adolescent patients with a mean age of 15.4 ± 2.4 years for girls and 14.7 ± 2.2 for boys, hospitalized at the Department of Pediatrics, Haemato-Oncology and Pediatric Gastroenterology of the Pomeranian Medical University in Szczecin. Patient recruitment took place from January 2019 to January 2021. The study was approved by the Bioethics Committee of the Pomeranian Medical University (regulation no. KB-0012/131/18).p-values were, respectively 0.929, 0.709). The diagnosis of IBD was made based on endoscopic examination (using an Olympus camera) with histopathological evaluation of the intestinal tissue collected during endoscopic examination, which was one of the inclusion criteria for the study. In addition, patients had an ultrasound examination. Whereas in the case of Crohn’s disease, enteroclysis or enterography with CT imaging was additionally performed. Patients aged 10 to 18 years with mild to moderate IBD on standard oral nutrition and not specialized elimination diets  were included in the study. Only patients with lactose intolerance who consumed lactose-free dairy products were included in the study (n = 10). Lactose intake was determined by interview and food diaries. Patients reported consuming dairy products without lactose. They did not eliminate dairy from their diet due to lactose intolerance. Exclusion criteria included the use of specialized elimination diets, other food allergies, and age below ten years.The study group consisted of 73 patients, while 20 patients refused to take part in the study. The study group consisted of 53 patients with IBD, including 27 patients with CD (8 girls and 19 boys) and 26 patients with UC (13 girls and 13 boys). The mean height and body weight were respectively 1.6 ± 0.1 and 54.5 ± 13.9 kg and for girls and 1.6 ± 0.2 and 52.7 ± 17.7 for boys. The differences in parameters were not statistically significant  Pediatric Ulcerative Colitis Activity Index (PUCAI) questionnaire. Remission of the disease was established by the attending physician through biochemical parameters of inflammation (erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), fecal calprotectin). Patients were taking the following groups of drugs: corticosteroids (n = 12), immunosuppressants (n = 25), aminosalicylic acid medications (n = 42), and biological treatment (n = 2). Most patients maintained the habits acquired during disease exacerbations even after going into remission; therefore, their diets did not differ between periods. Among girls, 47.6% took vitamin D supplements (including 50% with CD and 46.2% with UC), 9.5% supplemented with a multivitamin complex (including 12.5% with CD and 7.7% with UC). Referring to minerals, 23.8% supplemented calcium (including 50% with CD and 7.7% with UC) and 9.5% of girls supplemented potassium. Among girls, only 15.4% of UC girls were taking iron supplements. In turn, in the boys’ group, vitamin D supplementation was taken by 75% (including 78.9% with CD and 69.2% with UC), vitamin complex by 9.4% (10.5% with CD and 7.7% with UC). Referring to minerals, calcium was supplemented by 25% of boys (21.1% from CD and 30.8% from UC), potassium by 15.6% (21.1% from CD and 7.7% from UC), iron by 6.3% . Magnesium was supplemented by only 10.5% of boys with CD. Supplementation is not included in the daily intake.p-values were 0.342, 0.614, respectively).The control group was recruited randomly from age- and gender-matched healthy children from the local community in the winter of 2020/2021. General information about the study and its objectives was advertised via social media and paper flyers. Parent’s communicated their children’s willingness to participate by phone. During the telephone calls, it was confirmed that participating children met the following criteria: no changes in dietary habits in the three months prior to the study, including use of elimination diets; no chronic diseases, especially concerning the gastrointestinal tract; and no food intolerances or allergies. Overall, 32 parents gave consent for their children to take part in the study, but at last 20 children came for a face-to-face interview. The control group consisted of 10 girls and 10 boys, aged 14.3 ± 2.7 and 14 ± 3.2 years, respectively. The mean height and body weight were, respectively, 1.6 ± 0.1 and 51 ± 10.3 kg for girls, and 1.7 ± 0.1 and 52 ± 12.3 for boys. The differences in these parameters were not statistically significant (Anthropometric measurements such as body weight (±0.1 kg) and height (±0.5 cm) were used to assess differences in the nutritional status of patients. A medical scale  with a height gauge was used.Dietary patterns were assessed based on recalled nutritional diaries of the 72 h prior to the assessment. The dietary interview was conducted by a qualified nutritionist. An album of products and meal photos was used to ensure the collection of reliable information regarding the size of the consumed meals . AttemptThe results obtained were compared with the current nutrition standards for the Polish population. The norms were used according to the average age for both genders, respectively. The results were related to the estimated average requirement (EAR), or if this was not established to the adequate intake (AI).The reference of intake levels to norms is presented with a ±10% margin. The mean age of 13–15 years for girls and boys, respectively, was taken as the reference point for nutritional standards. To compare energy intake to norms, the average body mass and average age of the study group were used for boys and girls, respectively. All patients in the study group had low physical activity limited to a maximum of 2–4 h per week, which was also contributed to by the current epidemiological situation. The average activity of the group was set at a physical activity level of 1.50 for girls and 1.55 for boys. t-student-test. The non-parametric Mann–Whitney test was used to compare the intake of nutrients between the study and control groups. Statistical significance was established at a two-tailed value of p ≤ 0.05. Post hoc test power analysis was performed using G Power software . The power of tests showed statistical significance above 0.8.Statistical analysis was performed using Statistica 13.3 software . The distribution of the continuous data was tested using the Shapiro–Wilk test. Since most data in the study group did not differ significantly from the normal distribution, the analysis within the studied group was carried out using a parametric p = 0.0224), total protein (71.3 vs. 56.2 p = 0.0217), and animal protein (47.8 vs. 34.5 p = 0.0183). Thus, statistical significance was shown between girls in the intake of most amino acids (Supplement). Protein intake was at an adequate level in both groups. The ratio of animal protein to plant protein in the girls’ group exceeded 2:1, while in the boys’ group it oscillated around 2:1. Girls in the study group had a significantly higher intake of total carbohydrates (237.3 vs. 196.1 p = 0.0442) and assimilable carbohydrates (219.8 vs. 180.5 p = 0.7921) compared to girls in the control group. In contrast, boys with IBD showed a higher percentage of dietary carbohydrate intake relative to boys in the control group (55 vs. 48.5). Fat intake in both groups was at an adequate level. Intake of saturated fatty acids was excessive for both groups. Mean dietary carbohydrate intake was at normal levels in both groups. Additionally, in the study group, boys consumed significantly more starch than girls (150.8 vs. 110.7 p = 0.0029). An energy deficit was statistically significant in both CG and IBD groups. Girls in the study group, in relation to girls in the control group, showed a significantly higher intake of energy (1751. 3 vs. 1558.6 p = 0.0016). Saccharose intake did not exceed 10% of the dietary caloric intake in both groups relative to the mean. However, higher saccharose intake was observed in the IBD group relative to the control group. There was also a significantly lower intake of lactose in the IBD group of boys relative to the CG of boys (6.1 vs. 11.6 The mean fiber intake in both IBD and CG groups was below the accepted norm and did not differ significantly between them.p = 0.0199) and niacin (18.9 vs. 12.2 p = 0.0047) intake between girls (IBD vs. CG). In contrast, in boys, significant differences were found for riboflavin (1.3 vs. 1.7 p = 0.0123) (IBD vs. CG). A statistically significant difference in vitamin C (112.5 vs. 100.7 p = 0.0356) intake (girls IBD vs. boys IBD) was observed in the study group. None of the genders in both IBD and CG groups achieved the required levels of vitamin D and folate intake. Inadequate intake of vitamin D in the group affected 100% of girls and 96.9% of boys, and in both cases was at critically low levels of 1.4 ± 0.9 µg and 3.1 ± 3.2 µg, respectively. Adequate intake of vitamins such as vitamin A, B1, B2, B3, B6, B12 and C were observed in both the study and control groups. Both boys in the study and control groups showed insufficient intake of vitamin E, which was not observed in the group of girls.p = 0.0367) (IBD vs. IBD). Intake of iron, copper, and manganese met the norms in both groups. Girls with IBD consumed significantly higher amounts of manganese (4 vs. 2.4 p = 0.0447), potassium (2588.5 vs. 2054 p = 0.0416), and phosphorus (1167.1 vs. 933.4 p = 0.0345) compared to girls in the control group. Insufficient intake of potassium, magnesium, and calcium was found in both the control and study groups. Also, boys in the control group consumed significantly more calcium (851.8 vs. 432 p = 0.0006) and phosphorus (1357.5 vs. 1024.3 p = 0.0431) compared to boys with IBD. The highest deficiency among mineral components was observed in calcium, potassium, and magnesium. Potassium deficiency was higher in the girls’ group, while magnesium deficiency was higher in the boys’ group. Mean zinc intake was insufficient in the boys’ group (IBD). Insufficient intake of iodine, which was not observed in the boys, was observed in both the study and control group of girls. Regarding the mineral components presented in Malnutrition is common in children with IBD, especially in patients with CD, both in the exacerbation and in the remission phases of the disease . In patiIn this study, we aimed to analyze the differences between the nutritional patterns of children with IBD and healthy controls and to assess the alterations relative to dietary standards for the Poles. Children with IBD have a high risk of growth delay, and an inadequate intake can make this worse. Similarly, Diederen et al. showed lower energy intake in adolescents with IBD relative to healthy controls . In our A similar percentage distribution of fat intake was shown in a study by Vagianos et al. . MoreoveIn our study, higher carbohydrate intake was observed in the IBD group, especially among girls. This phenomenon also translated into higher assimilable carbohydrate intake in the IBD group relative to CG. The same observations were made in another study .The observed fiber deficiencies indicate that this nutrient is not commonly used in the diets of IBD individuals. However, dietary fiber intake in this study does not differ markedly from the reference standard. A low-fiber diet is often used by patients as a preventive measure. This is explained by the fear of recurrent exacerbation of the disease . ReducedRegarding fat-soluble vitamins, a drastically low intake of vitamin D was noted in both the study and control groups. Low vitamin D intake is commonly justified by the limited variety of foods in which the vitamin is present in relevant quantities . InadequRegarding the intake of minerals in this study, there was a significant deficiency of calcium and magnesium consumption in both groups. In addition, a significantly lower intake of this component was shown in IBD boys relative to CG boys. In contrast, mean zinc intake was below the recommended values only in the IBD male group. Inadequate zinc intake maintains inflammation. Adequate levels of this element may reduce the production of pro-inflammatory cytokines and the elevation of mucosal permeability in the course of CD . MagnesiProper eating habits are crucial for the overall well-being of an organism. Nutrition is a major factor contributing to the course of inflammatory diseases. Therefore, patients diagnosed with IBD should be treated in an interdisciplinary way in cooperation with a doctor and a dietician. Due to the risk of delayed growth and youth development associated with inadequate nutrition, dietary interventions should be introduced early. Moreover, nutrition education should be emphasized for a healthy pediatric population. We have not studied the influence of nutritional scales on the course of the disease and therefore cannot recommend a recommended intake of components. However, we would like to highlight the need for supplementation of selected components. We suggest considering supplementation in amounts above 50% of the requirement for calcium, magnesium, and potassium, as well as vitamin D and folate. Vitamins B1 and B3 and iron should be considered in the amount of about 20% of the demand. In addition, boys should be supplemented with vitamin E and zinc. A major limitation of the study is its relatively small sample size. However, more studies on nutritional assessment in children with IBD are warranted, especially in the context of ethnic diversity. In addition, people on elimination diets and patients with food allergies and severe disease may be at higher risk of deficiencies than our study group. Economic situation was not included due to the reluctance of a significant proportion of patients to answer questions related to social status.


Hepatectomy is always a challenge to surgeons and requires an appropriate approach for specific tumors to achieve effective complication management. Selective hepatic pedicle clamping is more considerable strategy when comparing with total hepatic pedicle clamping in the balance between reducing blood loss and transfusion with causing the hepatic parenchyma damages (two main complications affecting liver resection result).  In this study, we aim to describe the application of selective hepatic inflow vascular occlusion (SHIVO) and anatomical anterior approach in liver resection and evaluate the results, focusing on intraoperative and postoperative complications. 3) to body weight (kg) > 0.8% (for right hepatectomy). Perioperative parameters were collected and analyzed.  We enrolled 72 patients who underwent liver resection with SHIVO at Viet Duc University Hospital in 4-year period (2011-2014) and then followed up all of them until June 2020  or up to the time of death. All the patients were diagnosed with primary or secondary liver cancer, and their future remnant liver volume measured on 64-slice CT scan . There were no liver failure and biliary fistula after surgery. No deaths were recorded during 30 days postoperatively. Average hospital stay was 11.4 ± 3.7 days. Blood transfusions during the operation and major liver resection were the factors significantly affecting the percentage of complications after liver surgery in our study. In the last follow-up evaluation, 44 patients were dead and 28 patients were alive, in which 7 with recurrence and 21 without recurrence. The overall survival rate was 38.9%.  SHIVO in anatomical liver resection is a safe and feasible approach to help resect precisely targeted tumors and manage several complications in liver resection. Blood loss and blood transfusion during and after operation are essential prognosis factors for outcome in liver resection. One of the effective methods to limit such major complication is applying SHIVO . In recent years, SHIVO has been confirmed by many authors, usually in their single-kind hepatectomy (major or minor one) study, that it leads to fewer complications than total hepatic pedicle clamping (Pringle maneuver) as it helps reveal clearly the anatomically resected part of liver and reduce ischemia of remnant liver and intestinal congestion –3.To perform SHIVO, appropriate Glissonean pedicle has to be dissected and controlled for clamping. Bismuth and Makuuchi et al., based on principles of Lortat-Jacob and Ton That Tung methods, launched temporary SHIVO for both hepatic portal vein and hepatic artery of right or left Glissonean pedicle  to prevent from intestinal congestion and total liver ischemia, particularly in the remnant of liver , 5. Besi3) to body weight (kg) > 0.8% (for right liver resection). Exclusion criteria were liver resection related to total hepatic pedicle clamping in any step, requires concomitant bowel resection, combines liver and extrahepatic bile duct resection along with hepaticojejunostomy, or hepatic resection with radiofrequency ablation during surgery for other kind of lesions in the liver.We prospectively enrolled 72 patients who underwent liver resection with selective hepatic vascular occlusion at Viet Duc University Hospital from September 2011 to May 2014. The selection criteria were patients (i) diagnosed with primary or secondary liver cancer, (ii) whose lesions localized on one side of the liver (left or right), and (iii) with future remnant liver volume measured on 64-slice CT scan ; evaluate other organs in the abdomen such as stomach, small intestine, colon, and spleen; and create preliminary assessment of whether hepatic pedicle has either adhesion or enlarged lymph nodes.Step 3: liver mobilization: divide round ligament and falciform ligament and expose the anterior surface of suprahepatic inferior vena cava and root of three hepatic veins. Right Liver Mobilization. Divide right triangular and coronal ligament and mobilize the liver from diaphragm and right adrenal gland. Right liver mobilization depends on the type of liver resection .Left Liver Mobilization. Divide left triangular and coronal ligament.Hepatic Vein Control. Depending on types of liver resection, hepatic vein would be dissected and encircled.Step 4: cholecystectomy: insert a catheter into main bile duct through cystic duct, lymphadenectomy, or not  and common hepatic artery (station 8) would be removed or dissected depending on type of liver tumor, enlarged size of lymph nodes at this step, or not CholecysStep 5: selective hepatic inflow vascular control for occlusion . The right or left hepatic pedicle is intermittently clamped every 15-20 minutes during transecting hepatic parenchyma and then released for 5 minutes. The sectional Glissonean pedicle is clamped instead of right or left Glissonean pedicle if the transection line is in the same ischemia area.Step 6: transect liver parenchyma: after approaching and controlling the Glissonean pedicle , we transected parenchyma basing on the demarcation line and anatomical landmarks [Determine the transection line or plane based on the anatomical landmarks and fissure . If the Resect hepatic parenchyma with Kelly forceps, harmonic scalpel, or CUSA with or without bipolar electrocoagulation while implementing selective occlusion as described above. Intrahepatic vessels were ligated, clipped, and then dividedLiver parenchyma is transected, and Glissonean pedicle of resected parenchyma is clearly visible in hepatic parenchyma. Ligate or suture and divide Glissonean pedicle within parenchyma .andmarks . We finaIn the case of right or left liver resection with right or left portal vein thrombosis, hepatic artery and portal vein would be dissected and divided extrahepatically before transecting parenchyma. The biliary tract is eventually divided intrahepatically after parenchyma transection in order to prevent damage to the remnant bile duct due to anatomic biliary variation.Step 7: check bleeding and bile leakage and cover transection surfaceCheck Bleeding. This is a coagulation with bipolar electrocautery, suturing at oozing sites or ligating the stumps of vessels on transection surface of remnant liver.Inject normal saline into the catheter inserted into main bile duct through cystic duct for bile leakage detection and suturing bile leakage sites (if any)Cover transection surface with Surgicel, greater omentum, etc.Step 8: place drainage and close abdomen . Values are presented as mean ± SD (range) or median (range). Postoperative complications were classified according to Dindo-Clavien [The studied criteria were as follows: duration of pedicle isolation and overall surgery, blood loss, and transfusion requirements (both intra- and postoperation). Complete blood count and serum biochemistry including renal function and liver function were evaluated. Postoperative morbidity, mortality, and hospital stay were also obtained. Postoperative hemorrhage is defined as considerable blood loss from drainage, hematoma, or blood fluid or active hemorrhage detected by ultrasound or CT scan, and hemoglobin level is decreased 3 g/dl compared with immediately postoperative level. Bile leakage is diagnosed when drain fluid has bile-like color and total bilirubin concentration of drain fluid is more than 5 mg/ml or three times the serum concentration. Ascites is drain fluid amount more than 500 ml/day for at least 3 days or abdominal fluid is considerable in ultrasound. Postoperative liver insufficiency was defined as prothrombin < 50% and bilirubin > 50 -Clavien .For long-term outcome, all patients were reexamined 1 month after discharge and then followed up every 3 months with blood biochemistry (liver function), tumor markers, and abdominal ultrasound. Abdominal computed tomography (CT) scans were indicated every 6 months or when tumor recurrence is suspected.During postoperative follow-up, patients with recurrence would be informed and explained for further treatment. The recurrent treatment methods for patients should be the following: TACE, radiofrequency ablation, resurgery, and symptomatic treatment. The last follow-up evaluation was in June 2020 or up to the time of death.p value of <0.05 was considered statistically significant.Descriptive data were presented as means and standard deviations (SDs) and percentages. All data were analyzed with SPSS 21.0 . Using Fisher's exact test, with a All clinical investigations were conducted according to the principles expressed in the Declaration of Helsinki. Vietnam Military Medical University Institutional Review Board Committee approved the study protocol, and patients provided informed consent before participation. All patients provided written informed consent.From September 2011 to May 2014, a total of 72 patients were enrolled and received liver resection with SHIVO. Their mean age was 52.3 ± 10.7 years old . Most patients were men (83.3%). On the past medical history, 77.8% of patients had hepatitis B and/or C, 23.6% had previous TACE plus PVE, and 5.6% had previous single TACE. All patients had Child-Pugh A. There were 62 ones diagnosed with HCC (86.2%), while cholangiocarcinoma and colorectal liver metastasis had an equal proportion (6.9%). The mean tumor size measured by CT scan or/and MRI is 6.7 ± 2.9 cm , with 56.9% of patients having tumors > 5 cm and 4.2% of patients had >3 tumors. There were 7 patients (9.7%) figured out with portal vein thrombosis by CT and/or MRI .The approaches of Glissonean pedicle were described in In intrafascial approach group, there were 15 patients with previous PVE and 7 ones with portal vein thrombosis. Of these, there were 2 patients with left thrombosis invasive into portal trunk which required dissection of both portal trunk and the right portal vein to prevent the thrombosis from moving to the right portal vein.While dissecting Glissonean pedicle, bile duct injury occurred in 1 patient with the rate of 1.4%, bleeding was observed in 3 patients (4.2%), of which 2 patients already had parenchymal inflammation due to several previous TACE, both of incidents belonged to extrafascial approach. No patient had portal vein or hepatic artery injury during selective hepatic inflow vascular dissection with both intrafascial and extrafascial approaches.The average Glissonean pedicle dissection time was 12.5 ± 7.2 minutes, . There were 43 patients (59.7%) receiving minor hepatic resection. Cholecystectomy was performed for 61 patients (86.1%), and catheter was inserted into main bile duct through cystic duct for bile leakage checking 49 patients (68.1%), intraoperatively detected bile leakage through injecting normal saline into catheter 18/49 patients and postoperatively keeping the catheter 10/49 patients.The average hepatic parenchymal transection time and surgical time were 39.9 ± 13.3 minutes and 196.2 ± 62.2 minutes, respectively. The longest procedures belonged to resection of left liver along with segment 1, which was, respectively, 51.7 ± 5.8 minutes and 315 ± 39.7 minutes. The mean blood loss during surgery of the entire study was 261.4 ± 202.9 ml (range 30-1100 ml). Left liver resection had the largest average blood loss with the mean of 436.3 ± 319.4 ml .There were 7 patients having blood loss > 500 ml among 10 patients (13.9%) receiving intraoperative blood transfusion, and all these 7 patients were performed major liver resection and intrafascial Glissonean pedicle approach . Intraoperative blood transfusion 10 patients accounted for 13.9%, and 7 out of 10 patients were major liver resection. Intra and/or postoperative blood transfusion 12 patients accounted for 16.7%. Margin distance < 0.5 cm accounted for 12.5% (9 patients), 0.5–1 cm accounted for 41.7% (30 patients), and >1 cm is 45.8% (33 patients). That means almost all cases (87.5%) had upper 0.5 cm length from tumor to resection margin. Three patients (4.2%) had lymph node metastasis in 8 and/or 12 station.(1) Postoperative Kidney and Liver Function Test. Renal function of all patients after surgery on days 1, 3, and 5 was completely normal. There was no statistically significant difference (p > 0.05) between total bilirubin, albumin preoperative day, and postoperative days 1, 3, and 5. Liver enzymes GOT and GPT increased after surgery, of which the highest level was on day 1 and decreased gradually in the following days, statistically significant difference. On the fifth day after surgery, GOT and GPT reached an average of 60.6 ± 74.8 U/l and 88.9 ± 75.8 U/l, respectively. No major disorders observed in postoperative liver function tests  was the most common complication in the study. Postoperative ascites and bleeding accounted for 22.2% and 1.4%, respectively. No cases suffered from liver failure, bile leakage, or infected incision. No patients died in 1 month after surgery. According to Dindo-Clavien's classification of surgical complications, there were 55.5% of patients with no complications, and grade 1 complications accounted for 37.5%. We also observed no complications of grade 3B-grade 5 after surgery .The average hospitalization time of all patients was 11.4 ± 3.7 days (range 7-29 days).p < 0.05)  was found in the group with blood transfusion (intra- and/or postsurgery), removal or dissection of lymph node 8 and 12, and in major liver resection ( < 0.05) .n = 62), 19 patients were alive, in which 7 patients are with recurrence. This group had disease-free survival rates at 1-, 2-, 3-, 4-, and 5-year of 67.7%, 51.6%, 43.5%, 40.3%, and 37%, respectively. The 1-, 2-, 3-, 4-, and 5-year overall survival rates were 80.6%, 72.6%, 62.9%, 56.5%, and 50%, respectively. In cholangiocarcinoma group, 2 of 5 patients were alive and without recurrence, and 3 patients have died and had survival time of 6, 11, and 52 months. In colorectal liver metastasis group, all 5 patients were dead, and the survival time were 20, 27, 35, 56, and 56 months.The median follow-up was 52.6 ± 33 months . All 72 patients were fully followed. 44 patients have died, and 28 patients were alive: 7 patients with recurrence and 21 without recurrence. The 6-year overall survival rate was 38.9%. In HCC group  in order to decrease blood loss . HoweverIn terms of Glissonean pedicle division and ligation, there are two points of view. One is performing Glissonean pedicle dissection, and always divide and ligate the Glissonean pedicle before transecting parenchyma, using an encircling tape for counter traction to avoid damage to the remnant Glissonean pedicle –20. HoweWhile performing this dissection technique, we caused 1 bile fistula (1.4%) and 3 bleeding (4.2%). The bile fistula in the right hepatic bile duct was early discovered and fully sutured in the operation. Bleeding happened in extrafascial approach, from hepatic parenchyma around pedicle. These 2 cases already had previous inflammation due to TACE. We all well handled the three incidents with bipolar electrocautery and light pressure with gauze . Mouly eWhen performing anatomical liver resection, it is important to determine the transection line. In our study, this was produced by 2 methods. First is Glissonean pedicle occlusion of resected part of liver that revealed the demarcation line. This method is useful for posterior, anterior sectionectomy, or segmentectomy of right liver that is difficult to determine exact transection line. Second, we also transected parenchyma based on hepatic landmarks and fissures described by Ton That Tung but do not need to dissect and occlude the Glissonean pedicle of resected part of liver such as lateral segmentectomy or segment 4 resection . During p < 0.05), highest on day 1, and gradually decreased on the following tested days. Average postoperative total bilirubin on the same postoperative days increased compared to preoperative ones (p < 0.05), and the highest value is on day 3 before slipping down in day 5. Albumin and prothrombin are lower than before operation (p < 0.05) and dropped significantly on the 3rd day. Fluctuation of the above biochemical and coagulation indicators is similar to those of Fu et al. [Blood biochemical test and coagulation tests were performed on postop days 1, 3, and 5 to monitor liver and kidney function. u et al. . Fu et au et al. .Liver surgery is still a challenge for surgeons. Recent studies show that although the postoperative mortality rate is reduced and usually less than 5%, the complication rate is still high. Belghiti et al.'s study of 747 cases of liver resection showed that the postoperative death rate was 4.4%, and the group of diseased liver had significantly higher death rate (9.5%) than the group of normal liver (1%) . The posIn our study, no patients died within 30 days after surgery. Based on Dindo's complication classification, p < 0.05).There are many risk factors for complications and mortality after a liver surgery. These factors can be the patient's characteristics , liver function, tumor's characteristics , and particularly operative factors related . There are different perceptions of factors that influence early results. Kamiyama et al. suggested that surgery time > 360 minutes, blood loss > 400 ml, and blood albumin < 35 g/l are factors leading to complications after liver surgery . For cirTo sum up, when performing liver resection with anterior approach in combination with selective hepatic pedicle occlusion , we found that this is a safety procedure without long duration (mean dissection time was 12.5 ± 7.2 minutes) and there were nearly no major complications. Only minor ones like biliary fistula or parenchymal bleeding around hepatic pedicle were observed, which were well controlled.Bleeding control in this approach is as effective as total hepatic pedicle occlusion when the resected part of liver is completely corresponded with the dissected pedicle , 11. For2O would help reduce blood loss from the hepatic veins [Bleeding is still happening from the hepatic veins and transection surface of remnant liver during right or left liver resection. However, reducing central venous pressure < 5 cm Hic veins . MoreoveSelective pedicle clamping and anterior approach is a safe, feasible, and effective method to resect precisely targeted tumors in hepatectomy and reduce blood loss, transfusions, and several complications in the remnant liver. While extrafascial approach had shorter dissection duration, intrafascial approach should be recommended in patients with previous thrombosis and portal vein embolization.


Median OS after HMA in patients with SD as best response to HMA was similar to median OS in patients with response to HMA (10.6 months vs. 13 months). On multivariate analysis, OS difference between patients who obtained a response versus patients who did not was significant (p = 0.0037). OS difference in sAML was significantly better than in de novo AML (p < 0.00001). HMA showed a remarkable efficacy in terms of response rate and OS in a subgroup of patients (sAMLs), historically characterized by a poor outcome. Therefore, 5Azacitidine and decitabine may represent a good clinical option in a selected patient population with relapsed or refractory AML, unsuitable for allo-HSCT.Data on the use of azacytidine and decitabine as salvage therapy for acute myeloid leukemia are limited. We retrospectively reviewed clinical records of 100 patients treated with hypomethylating agents (HMA) as salvage therapy in nine Italian institutions. A total of 24% of patients obtained a response to HMA , while 26% showed a stable disease (SD); 50% of patients experienced progressive disease. Median OS was 6.5 months. OS in patients with de novo AML was 6.1 months, while OS in patients with secondary AML (sAML) was 12.3 months ( Relapsed AML is a potentially curable disease, but results of salvage therapy are generally dismal, with median survival of 4–6 months only, with a trend towards worse outcomes in patients aged ≥60 year , and no Adult patients, affected by AML diagnosed according to 2016 World Health Organization (WHO) criteria, and previously treated with HMAs at relapse were retrospectively enrolled in the study. Disease status included relapsed AML ), and refractory leukemia to at least one course of intensive chemotherapy (IC). Patients who received HMA before alloHSCT and patients who received HMA as first-line therapy were excluded. Clinical and biological data referring to the period from 2006 to 2017 were collected by every center, and datasets were combined and analyzed by the coordinating center . The study was approved by the institutional review board of Padua University Hospital (ID 4227/AO/17 on 6 July 2017) and was conducted in accordance with the Declaration of Helsinki. Relapsed AML was defined by the recurrence of >5% blasts in the peripheral blood and/or bone marrow of patients after achieving a complete remission (CR), treated with one or more lines of therapy [p < 0.05.Survival analysis was performed using Kaplan–Meier curves. Significance in survival time between groups was tested using log-rank test. In multivariate analysis, the Cox proportional hazard model was used to find the true independent factors. Significance was set at One hundred AML patients were included in the study: 68 males and 32 females. Median age at diagnosis was 64.3 years. A total of 29% of patients were affected by secondary AML. One patient was AML with t, two were AML with t, one was AML with inv(3), one patient was AML with inv(16), twenty-seven were AML MRC, two were therapy-related AML, and sixty-one were AML NOS. According to ELN 2017 risk stratification, 10 patients were favorable risk, 50 were intermediate risk, and 33 were adverse risk. Cytogenetic risk was not available for seven patients. A total of 80 patients were treated with azacytidine (75 mg/sqm for 7 days every 28) and 20 with decitabine, at the standard dosage of 20 mg/sqm for 5 days every 28. A total of 60% of patients received HMA as second-line therapy for their disease, 29% as third-line and 11% were beyond third-line therapy. Among the 60 patients who received HMAs as second-line therapy 35% were 70 years old or older, 40% had a PS ECOG score of 2 or more, 36.7% had adverse cytogenetic risk; 40% of patients had at least one of the above-mentioned characteristics, 33.3% had two, 3.3% had three and only 23.3% had none. A total of 20% of patients underwent allogeneic stem cell transplantation before HMA, and 31.6% of these received concomitant donor lymphocyte infusions. All patients underwent intensive chemotherapy  as first-line induction. Performance status ECOG at the beginning of HMA was 0 for 19% of patients, 1 for 30% of patients, 2 for 41% of patients, and >2 for 10% of patients. A total of 54 patients had relapsed AML, and 44 patients had refractory AML. Data were not available for two patients. Median number of HMA courses was three (range 1–39). Patient characteristics are reported in p = 0.037). (p = 0.055) (p = 0.03). As expected, a better performance status may influence a better outcome: patients with ECOG 0 at the beginning of HMA showed a median OS of 19.6 months, while patients with ECOG 1–2 or 3–4, showed a median OS of 6.5 months and 2.1 months, respectively (p < 0.00001) , partial remission (PR) and CR with incomplete hematologic recovery (CRi)), 26% of the patients had a stable disease (SD), and 50% of patients showed no response to HMA. Median number of therapy courses to reach a response was four (range 1–9). A total of 50% of patients with adverse cytogenetic risk and 42% of patients with favorable/intermediate cytogenetic risk reached a response or a stable disease with HMA. Median OS of the whole cohort was 6.5 months, with a statistically significant difference between de novo AML (6.1 months) and secondary AML (12.3 months) ( 0.037). . Conside= 0.055) . We obse0.00001) .p < 0.00001). On multivariate analysis, OS differences between: 1) secondary AML and de novo AML; 2) SD and responsive group vs. progressive disease group; and 3) patients with ECOG 0 and >1 remained significant. Hazard ratio for death for secondary AML vs. de novo AML was 1.84 ; for ECOG 1–2 patients vs. ECOG 0 patients it was 3.1; and for ECOG 0 vs. ECOG 3–4 it was 6.2, .Median OS after HMA in patients with SD as best response to HMA was similar to median OS in patients who obtained a response to HMA (10.6 months vs. 13 months), while OS in unresponsive patients was 3.3 months .Median number of hospitalization days during HMA was 7.5 days (range 1–55), with 56% of patients never having been hospitalized. A total of 88% of patients did not experience any major infections during treatment (defined as grade 3 or worse according to CTCAE), 8% of patients experienced one major infective event and only 3% experienced three or more major infective events. Regarding fungal infections, 91% of patients did not experience any of them, 7% had possible and 1% proven infection. We did not collect any probable fungal infections in our data set. A total of 58% of patients did not experience any episode of neutropenic fever, 21% experienced one, 12% experienced two and only 8% experienced three or more. We did not find any significant differences between packed red blood cells transfusion needs before and after best response to therapy, and we found a worsening in platelet transfusion needs after best response to HMA   and withIDH inhibitors, FLT3 inhibitors, venetoclax [Mechanism of action of HMAs includes not only DNA methylation but also immunomodulating effects, as demonstrated by studies mainly in the setting of alloHSCT, involving an upregulated expression of tumor-associated antigens by leukemic blasts ,21. In onetoclax ,23), aftAs far as toxicity is concerned, most of the patients did not experience any infective event during treatment, probably due to wide use of antifungal and antibacterial prophylaxis in this population. This may explain the small rate of hospitalization, the good quality of life reported by patients and the consequent cost reduction. Further prospective studies on the quality of life assessment are required to confirm these observations.HMAs could represent a good therapeutic option in a selected population of relapsed elderly AML patients, not suitable for alloHSCT, apparently regardless of cytogenetic risk, and for whom the preservation of a good quality of life should be privileged. Further studies are needed in order to define which is the right population who can benefit from these agents, what is their role in transplant eligible patients and whether these results can be affected by the combination of novel targeted agents.


Using CPV and CCS intra-granular resulted in increased disintegration time and Q80. However, at a higher level of appx. 500 s and appx. 15 min, only SSG showed a process and location independent disintegration and dissolution performance.The current study evaluated the effect of location and amount of various superdisintegrants on the properties of tablets made by twin-screw melt granulation (TSMG). Sodium-croscarmellose (CCS), crospovidone (CPV), and sodium starch glycolate (SSG) were used in various proportions intra- and extra-granular. Tabletability, compactibility, compressibility as well as friability, disintegration, and dissolution performance were assessed. The extra-granular addition resulted in the fasted disintegration and dissolution. CPV performed superior to CCS and SSG. Even if the solid fraction (SF) of the granules was lower for CPV, only a minor decrease in tabletability was observed, due to the high plastic deformation of the melt granules. The intra-granular addition of CPV resulted in a more prolonged dissolution profile, which could be correlated to a loss in porosity during tableting. The 100% intra-granular addition of the CPV resulted in a distinct decrease of the disintegration efficiency, whereas the performance of SSG was unaffected by the granulation process. CCS was not suitable to be used for the production of an immediate-release formulation, when added in total proportion into the granulation phase, but its efficiency was less impaired compared to CPV. Shortest disintegration (78 s) and dissolution (QThe online version contains supplementary material available at 10.1208/s12249-021-02056-0. Melt granulation is an alternative granulation method to formulate powders that are not suitable for direct tableting because of their poor flowability or compactibility. Since melt granulation does not require the addition of solvents, the process is also interesting for water-sensitive compounds . The graImmediate-release formulations are often desired to obtain a fast onset of the therapeutic effect of the API. Disintegration of these tablets is the first step before the drug dissolves and therefore of fundamental importance to achieve bioavailability and a rapid onset of the therapeutic effect of the drug.In general, disintegrants cause the tablet to break up, when it comes in contact with water and helps to overcome the cohesive forces in the compact. The resulting particle size and the available surface generated after disintegration enhances the dissolution rate of the API. Early disintegrants included starch- and cellulose-based excipients, such as natural starch, pregelatinized starch, microcrystalline cellulose, and low-substituted hydroxypropyl cellulose. Due to chemical modifications, which decreased solubility and increased hydrophilicity at increased swelling, more effective disintegrants were developed, so-called superdisintegrants. They can be classified in chemically modified cellulose (croscarmellose sodium (CCS)), chemically modified starches (sodium starch glycolate (SSG)), and in pure synthesized copolymers, like crospovidone (CPV). Disintegrants act via different mechanism (e.g. swelling or shape recovery). In the case of swelling, the disintegrant absorbs water from the surrounding medium. This swelling results in multidirectional disruption of the tablets or granules structure during the disintegration process. The effectiveness of the disintegrant is dependent on the swelling extent and the swelling force generated during the water uptake. In the case of shape recovery, particles that are deformed, e.g. by the tableting process, regain their original shape, if water penetrates into the tablets, resulting on a unidirectional deformation of the tablet matrix.Disintegration is often concentration dependent, resulting in an optimal concentration to achieve the best disintegration effect , 17. At This is especially important, when high drug concentrations with a poor solubility are in focus . HoweverWhen disintegrants are added intra-granular prior to the melt granulation step, temperature and shear during the granulation process might influence the disintegrant performance. Until now, no systematic evaluation of different superdisintegrants exists concerning their suitability to be added to the melt granulation process.The current study sought to examine the need of disintegrants to obtain immediate-release tablets prepared from twin-screw melt granules.In this study, the three different superdisintegrants , with a comparable mean particle size of 40 μm, were tested in three weight fractions ). Moreover, in the case of the 6% (w/w) formulation, varying portions of this amount were added intra-granular. The effect on tabletability, friability, disintegration, and drug dissolution was tested on a model formulation of paracetamol (PCM) and polyethylene glycol 6000 (PEG) as a melt binder.As model excipient, the highly soluble drug paracetamol (PCM) was chosen to show process-related influences on the disintegration and drug dissolution, rather than effects that are related to poor wettability or poor solubility of the drug itself. PCM has no lack in solubility (23.7 mg/ml at 37°C), its solubility is not pH-dependent below pH 9, and it belongs to the biopharmaceutical classification system (BCS) class III .50 = 7.6 μm  dry-dispersed with a pressure of 1 bar, focal length 200 mm, calculated according to Frauenhofer theory, software Windox 4.2.1.) was obtained from Mallinckrodt Pharmaceuticals . Due to its low melting point (55–60°C), the binder PEG 6000 was used and purchased from Carl Roth . Granulation of PCM required the addition of 1% (w/w) colloidal silicium dioxide (AEROSIL® 200) which was a gift from Evonik . Sodium starch glycolate (Vivastar® P) and croscarmellose sodium (Vivasol® GF) were donated by JRS . Additionally, crospovidone (Kollidon® CL-F) was tested as a disintegrant, which was a gift from BASF . Magnesium stearate (Ligamed® MF-2-V) was donated by Peter Greven .PCM (dPCM was formulated with 10% (w/w) PEG as binding material. PCM required the addition of 1% (w/w) colloidal silicium dioxide (SDO) to enable feeding of the material into the extruder. PMs (batch size: 150 g) were prepared by using a Turbula blender , rotating at 50 rpm for 10 min. The obtained PMs were further used for twin-screw melt granulation (TSMG). Depending on the formulation, disintegrants were added proportional in the mixture. Short names used in text and graphics of this study are given in Table TSMG (batch size: 150 g) was performed using a co-rotating twin-screw extruder  with a functional length of 25:1 L/D (length/diameter) and a 12 mm screw diameter  was used to enable a constant feed rate of 0.1 kg/h. Granules obtained were further dry sieved using a 1 mm sieve in an Erweka wet granulator FGS with an AR 402 drive unit  prior to compaction.The particle size distribution (n=3) of the disintegrants was measured with a laser diffraction (λ= 655 nm) particle size analyser . A dry dispersion method was used with a pressure of 3 bar. The SPAN represents the width of the PSD and is calculated using Eq. :1\documImages of the disintegrants were taken using a scanning electron microscope . The samples were mounted with a double adhesive photo sticker and coated with a thin layer of gold using a sputter coater for 2 min at 1.7 kV . Images were captured at an acceleration voltage of 10 kV in high vacuum mode and a secondary electron detector.Pycnometric density was measured using the AccuPyc 1330 helium pycnometer . The chamber was purged 20 cycles prior to analysis. A fill pressure of 136.86 kPa and an equilibration rate of 0.0345 kPa/min were used for measurements. The cycle was repeated up to 25 times or until a standard deviation of 0.01% was reached. The density was employed for the calculation of the SF.The tablets (n=5) were compressed on a single punch tablet press  with a 8 mm flat face tooling. Five levels of compaction pressures from 50 to 250 MPa were applied at constant tableting speed . The die was filled manually.After 24 h of storage, the tablets were analysed by means of their tablet weight , height , diameter, and crushing strength . The tensile strength , anF is the crushing strength, d the diameter, and h the thickness of the tablet.where Papp) of the compact calculated from the tablet weight (m) and its volume relative to the pycnometric density (Ppyc) of the powder.SF (Eqs. –5)) rep) rep5)) Vp is the volume of the compact calculated based on d and h, which describe the tablet diameter and thickness.In Eq. , Vp is tThe tablets for friability, disintegration, and dissolution studies were produced with a clinical relevant concentration of 500 mg PCM. Tablets were compressed with a compaction simulator  and a 13 mm round tooling. A compaction pressure of 150 MPa was applied at constant tableting speed .The friability of the tablets was tested according to Ph. Eur. 2.9.7 : FriabilThe disintegration test (n=6) was performed according to Ph. Eur. 2.9.1. and the monograph of uncoated tablets . The dis80%, giving the time point at which 80% of the formulation is released. The USP 41 requires minimum of 30 min for the 80% dissolution of the “acetaminophen tablets” in phosphate buffer (pH = 5.8) (Dissolution tests (n=6) were performed using a USP Dissolution Apparatus 2 (paddle method)  with a rotation speed of 50 rpm. Analysis was performed according to the USP monograph for acetaminophen tablets with 900 ml of phosphate buffer at a pH of 5.8 ±0.1 and a set temperature of 37.0°C ±0.5°C. Tablets (n=6) containing 500 mg PCM were used for each experiment. For quantitative analysis, an Agilent 8453 in-line UV-VIS spectrophotometer  was used. Absorption was determined at a fixed wavelength of 260 nm. Dissolution tests were performed over a maximum period of 6 h with a maximum interval of 10 min between the measurements. Dissolution results were compared using QH = 5.8) , whereasH = 5.8) .All disintegrants had a comparable mean particle size of 40 μm Table . The parSEM images determined similar particle size distribution of the disintegrants but a different morphology and shape. CCS Fig.  had a moDensities of the formulations under investigation are given in Table 2 at 150 MPa vs. CCS 8%: 2.53 ±0.10 N/mm2 at 150 MPa). In the case of using crospovidone (CPV), the addition of the disintegrant can slightly lower tensile strength (TS). This was pronounced, when high weight fractions of CPV were added extra-granular: CPV 8% (2.08 ±0.05 N/mm2 at 150 MPa); 6% (2.26 ±0.07 N/mm2 at 150 MPa); and 6% 20% intern (2.03 ±0.16 N/mm2 at 150 MPa)  and 100% intern (3.05 ±0.09 N/mm2 at 150 MPa)). When high weight fractions of SSG were added extra-granular (SSG 6% 20% intern (2.09 ±0.03 N/mm2 at 150 MPa), SSG 6% 40% intern (2.15 ±0.08 N/mm2 at 150 MPa), and SSG 6% 60% intern (2.21 ±0.05 N/mm2 at 150 MPa)), TS was slightly lowered. However, the effect was not pronounced for the SSG 6% (2.45 ±0.13 N/mm2 at 150 MPa) extra-granular, indicating that the effect was not concentration dependent.Figure Pa) Fig. . Figure In Fig. However, using SSG intra-granular (SSG 6% 80% intern and 100% intern) showed a higher bonding capacity than the formulation without disintegrant (Gr. PCM 10% PEG) and the formulations with high amounts of SSG extra-granular.vs. CCS 8%: 0.90 ±0.01 at 150 MPa)  Fig. . Figure Pa) Fig. , the SFsIn general, friability studies confirmed the results obtained from the tabletability studies Table . All tabConcerning their friability, all tablets produced with CPV met the requirements of the Ph. Eur. No clear trend among the different weight fractions of CPV was observed, which verified the results obtained from the compression studies. The lowest friability was measured for the tablets containing 6% CPV and 1% SDO (0.13%) extra-granular, followed by the tablets with 6% intra-granular (0.16%), indicating no influence on tablets friability.vs. SSG 8%: 0.43%). The SSG intra-granular addition decreased the effect again, towards that of the tablets without disintegrant (SSG 6% 100% intern: 0.26% vs. Gr. PCM 10% PEG: 0.22%). However, the effect might be not relevant for commercial tablet production, since all tablets met the requirements of the Ph. Eur., as they showed a friability less than 1% (w/w).Overall, the friability of the tablets produced with SSG was slightly higher than the friability of the tablets produced from the granules without any disintegrant (Gr. PCM 10% PEG: 0.22%). In addition, an increasing friability as a function of SSG weight fraction was obvious (SSG 4%: 0.28% vs. CCS 8%: 390 ± 93 s). The disintegration time decreased with increasing CPV content. However, the addition of CPV intra-granular resulted in increasing disintegration time. The higher the integrated amount, the slower the disintegration process. Tablets using 100% CPV intra-granular (957 ± 97 s) did not disintegrate within 15 min and failed the requirements of the Ph. Eur. 2.9.1.According to Ph. Eur. 2.9.1., uncoated tablets must disintegrate within 15 min, which is equal to a time of 900 s. Tablets produced without disintegrants are disintegrated within 30 min (1775 ±327 s), indicating that these tablets did not meet the requirements for an immediate-release formulation. Using CCS as disintegrant, all formulations under investigation showed an acceptable disintegration time Table . No cleaOverall, formulations using SSG showed the longest disintegration times (SSG 8%: 513 ±38 s). SSG 6% 20% intern (319 ±50 s) exhibited lower disintegration time, than the other formulations. No clear trend could be observed concerning the disintegration efficiency, as it was seen for CPV Table .To meet the USP, a Q=80% release within 30 min for PCM tablets is needed , whereasTablets without any disintegrant exhibited a slow dissolution, which followed a zero-order kinetic in the first hours Fig. . A relea80% interval [min]. Regarding the CCS formulations, dissolution increased only slightly as a function of disintegrant content , CCS 6% 80% intern (Q80%= 36.7 ±2.6 min), and CCS 6% 100% intern (Q80%= 40.0 ±3.2 min).Figure ent Fig. . In the 80%= 4.2 ±0.4 min) was integrated extra-granular  and 6% CPV (Q80%= 5.2 ±1.0 min) extra-granular resulted in a very fast release, indicating the high potential of the disintegrant to enhance dissolution of the tablets. However, using CPV intra-granular delayed release, especially when more than 20% where integrated, tablets with 20% (Q80%= 5.5 ±2.1 min), 40% (Q80%= 14.5 ±6.3 min), and 60% (Q80%= 16.5 ±1.6 min) of the 6% CPV intra-granular still met the requirements of the USP and tablets achieved more than 80% drug release within the first 30 min.In the case of CPV, the fastest release was obtained, when 8% CPV .When 100% of CPV were granulated, CPV lost a remarkable proportion of its disintegration efficiency. Tablets of CPV 6% 100% intern achieved 80% release within more than 90 min (Q80%= 32.8 ±6.5 min) did not meet the requirements of the USP. However, in the case of 6% (Q80%= 17.7 ±3.7 min), results were comparable to those of CCS, but not as effective as CPV. Interestingly, the incorporation intra-granular of SSG does not result in any loss of the disintegrant efficiency, as it was seen for CCS and CPV.Using SSG resulted in the slowest dissolution profile considering the 4% extern formulations of the three disintegrants Fig. . The for80%= 7.0 ±1.3 min) performed more effective than CCS (Q80%= 17.0 ±2.4 min), and CCS was more effective than SSG (Q80%= 32.8 ±6.5 min). Using 6% extra-granular, CCS and SSG performed similar (Q80%= 15.2 ±3.7 min and 17.7 ±3.7 min), whereas the 8% extra-granular CCS (Q80%= 11.0 ±0.0 min) was more efficient than the respective SSG formulation (Q80%= 14.7 ±0.8 min). In both cases (6% and 8% extra-granular), CPV was superior, showing very short time to achieve 80% release of only 5.2 ±1.0 min and 4.2 ± 0.4 min. Using 1% SDO as additional wicking agent had only a minor effect on the release rate and did not significantly impact the dissolution, when compared to the 6% disintegrant extra-granular. In the case of adding 20% of the 6% disintegrant intra-granular, Q80% did not change compared to the 100% extra-granular formulation using CCS and CPV. For SSG, the 6% 20% intern formulation performed marginally faster than the SSG 6% formulation (Q80%= 12.7 ±0.8 vs. 17.7 ±3.7). Similar relations were already seen in the disintegration results (Table 80% increased for CPV (Q80%= 14.5 ± 6.3 min), but for CCS and SSG, the data were similar to those of the 6% formulation containing the disintegrant extra-granular. Using CCS, Q80% increased above the critical value of 30 min, using more than 60% intra-granular. In the case of CPV, using more than 80% intra-granular resulted in tablets that did not meet this requirement of the USP. Using 100% intra-granular resulted in tablets that achieved 80% release within more than 90 min, indicating noteworthy loss of the disintegration efficiency. SSG showed no remarkable loss of its disintegration efficiency when integrated into the granulation process.Using 4% extra-granular, CPV (Qts Table . In the Results show that the disintegration and the dissolution of the tablets were less dependent on the disintegrants concentration but rather on the location of the disintegrant (extra- or intra-granular).In general, the extra-granular disintegrant addition resulted in the fastest dissolution of the model compound PCM. Looking at the formulations with disintegrant extra-granular, the rank order of performance was CPV faster than CCS faster than SSG. Furthermore, the concentration needed of SSG was higher than that of CCS and CPV to meet the requirements of the USP.Except for the SSG formulation, no difference between the 4 and 6% extra-granular formulations was seen. However, 8% CPV and CCS extern was more effective than using 4% CPV and CCS, but the effect might be irrelevant for the patient’s therapy.In literature, the three superdisintegrants are often compared –35 and vThe results obtained in this study might be explained by the different mechanisms of action of the disintegrants. Proposed mechanisms of disintegration are wicking, swelling, shape recovery and particle repulsion, which lead to a disruption of the physicochemical bonds in the tablets –43. SyneCCS and SSG are known to act via swelling, which leads to a multidirectional volume expansion of the compact. However, the water uptake and swelling capacity of SSG is higher compared to CCS, whereas CPV shows only a low swelling capacity , 45. TheThis might be attributed to the very low porosity of the tablets made from the TSMG in contrast to the study of Berardi et al.  and FerrIn this study CCS and CPV showed a concentration dependent decrease in their disintegration efficiency (Tab. 7), when integrated intra-granular. The effect was more pronounced for CPV. Tablets using 100% CPV intra-granular did not disintegrate within 15 min, whereas tablets using 100% CCS still meet the requirements of the Ph.Eur. However, looking at the dissolution profiles, tablets with more than 40% of CCS intra-granular did not meet the requirements of the USP. This concentration dependent behaviour was not seen for the formulation produced with SSG.The effect of extra- and intra-granular addition of disintegrant is diversely discussed in literature, mainly depending on the formulation characteristics, rather than on the disintegrant itself. Some authors found improved efficiency of the disintegrant when added intra-granular, whereas others found contrary results , 53, 54.If the disintegrant is coated with a film of hydrophobic or slowly dissolving substance, disintegration might be negatively affected. This effect is well described for MGST, which can slow down disintegration or the dissolution rate, due to a hydrophobic surface coating. This effect was shown to be less pronounced for disintegrants that undergo intensive swelling like SSG , 59.The omnipresent PEG in the tablet after the granulation process results in a viscous gel when coming into contact with water. This effect might explain a loss in dissolution efficiency of CPV and CCS.The loss of disintegration efficiency, e.g. during wet-granulation process, was already described , 60, incSimilar effects might explain the loss in disintegration and prolonged dissolution of the compacts in this study, as the TSMG process applies high shear energy to the product, the use of kneading elements might result in a destruction of the disintegrants structure, resulting in a loss of their efficiency. This hypothesis is supported by the results obtained from the compressibility studies. The formulations containing CPV extra-granular showed a lower SF (higher porosity) compared to the formulations containing CPV intra-granular. This might be explained by a change of the structure of CPV during granulation, negatively affecting its elastic recovery during tableting process and consequently the disintegration and the dissolution performance of the formulation. Interestingly the lower SF of the formulation with CPV did not influence the TS of the tablets in a large extent. This can be explained with high plasticity of the melt granules , maintaiIn contrast to CPV, the majority of the SSG particles might be unaffected by the granulation process, therefore most of the enormous swelling capacity is maintained after the granulation process. Moreover a positive effect on the TS of the formulations containing high concentrations of SSG intra-granular was observed. The higher TS did not negatively influence the dissolution performance of the tablets.max: 95°C and absence of water) and maintained its disintegration capacity.However, it was postulated that the heat exposure during the melt granulation process, might result in an unwanted loss of disintegration efficiency, especially when using starch-based disintegrants. A pregelatinization might occur, negatively affecting the disintegration performance . In cont80%. At the same time, the benefits of tablets from TSMG like excellent tensile strength and friability could be remained even in combination with a high drug load (> 80% (w/w)). The rank order in efficiency for extra-granular addition was CPV > CCS > SSG. For SSG, higher concentrations of >6% (w/w) were needed, whereas already 4% (w/w) achieved acceptable results for CPV and CCS. Intra-granular addition showed mainly negative effects on the disintegration performance. This effect was very pronounced, when CPV was added into the granulation process and to a lesser extent for CCS. In contrast, SSGs disintegration efficiency was unaffected by the granulation process. The results are of fundamental importance, when using TSMG in a continuous processing line and additional mixing steps after granulation should be avoided.The current study showed that especially extra-granular addition of superdisintegrant revealed fast disintegrating tablets with subsequently short QHigh Resolution Image (TIF 2165 kb)ESM 2(DOCX 14 kb)


Finally, linear regression analysis was employed to quantify the relative contributions of environmental parameters to the reduction in the concentration of the four types of particulate matter in the summer and winter. The results showed that particulate matter concentrations exhibit spatial and seasonal differences in UVSs. A single landscape parameter was correlated with particulate matter concentration, while compound environmental parameters had significant effects on the particulate matter concentration in UVSs. Meteorological factors and greening structures had a dominant impact on the particulate matter concentrations in summer and winter, respectively. Therefore, adjusting and optimizing the environmental parameters could reduce particulate pollution in UVSs and could have practical significance for the planning and design of UVSs.Particulate pollution caused by urban traffic emissions has become a significant public hazard. Many urban roads of under-viaduct spaces (UVSs) have become concentrated areas of particulate pollution. This study aims to explore the effects of landscape parameters on particulate matter in UVSs in Wuhan, China. We selected 14 types of UVS sections and nine potential environmental parameters to monitor four types of particulate matter (PM Air pollution caused by rapid urbanization harms the balance of urban ecosystems, the health of residents, and socioeconomic development . Among tChina has been experiencing severely degraded air quality conditions owing to rapid economic growth, industrialization, and urbanization ,6. For eRoad traffic emissions are the primary source of urban particulate pollution  and can Urban environmental parameters determine whether particulate matter can be abated, and meteorological factors  are considered to be essential factors that influence particulate pollution . Additio10), ≤2.5 µm (PM2.5), ≤1.0 µm (PM1.0), and total suspended particulates (TSP)), the research focuses on three aspects: (1) the spatial and seasonal distribution characteristics of particulate matter of UVSs in Wuhan, (2) the characteristics of the effects of environmental parameters on particulate matter concentration, and (3) the practical significance of optimizing environmental parameters for the abatement of particulate matter in UVSs.This study explores the effects of environmental parameters on particulate matter in UVSs. Using Wuhan, China as an example, we selected 14 types of UVS sections and nine potential environmental parameters. Based on the survey and monitoring of four types of typical particulate matter  were measured with temperature-humidity recorders and dust monitors. We explored the effects of nine environmental parameters of UVSs on the four particulate matter types through statistical analyses.Considering the diversity of viaducts and greening structure types in Wuhan’s UVSs, 14 UVS sections were selected as samples for monitoring in this study. Based on satellite images and field investigations, the temperature, humidity, and concentrations of particulate matter , a metropolis in central China A, is dom2 . AccordiBoth the location and quantity of pollution sources affect particulate matter concentration . The pri1.0, PM2.5, PM10, and TSP were measured on sunny and windless or breezy days (wind speed ≤ 5.4 m/s) to avoid the potential impact of meteorological factors . Additionally, to reduce the measuring error between sampling sites, the particulate matter concentration was measured during peak traffic hours, namely, from 07:00 to 09:00 and 17:00 to 19:00 (Beijing time). A complete monitoring period comprised of three consecutive days and three periods were conducted during each season. The mean concentration during the monitoring periods was used as the final concentration.The monitoring period selected was during typical summer and winter periods in Wuhan. Moreover, the concentrations of PM1.0, PM2.5, PM10, and TSP concentrations were monitored during three-day periods. All fixed-point monitors were set in the center of the sidewalk outside the viaduct (3–10 m away from the viaduct) and at 1.5 m above the ground [1.0, PM2.5, PM10, and TSP concentrations were monitored simultaneously. Three consecutive groups of measured values were selected for calculating the mean particulate matter concentration at the moving-point. Finally, owing to a deficiency in instruments, we were only able to acquire size data for one type of particulate matter for fixed-point monitoring each day. The calculated values according to PM10/TSP [2.5/PM1.0 [The particle measurement of 14 UVS samples included moving-point and fixed-point monitoring simultaneously . The move ground ,28. The PM10/TSP ,30 and P.5/PM1.0 ,32 ratio10, dPM2.5, and dPM1.0) between the moving points and corresponding fixed points as indicators of the difference in particle concentration at each sampling site [Considering the potential spatial background difference of airborne particle level in the urban environment, we took the net concentration difference  based on previous studies, potential environmental parameters affecting the particulate matter concentration were identified ,22,33; .The detailed procedure included the following steps: (1) the temperature and humidity  in the UVSs were measured by the temperature-humidity recorder; (2) the greenbelt width (UVSgw) and greening area (UVSga) in the UVSs were measured using a measuring tape and laser range finder, and the UVSga was calculated; (3) the ambient greening area (Aga) around the UVS sample sites, ambient building distance (Abd), ambient building area (Aba) , and ambient opening degree (Aod)  were calculated based on satellite images and field measurement data; and 4) the viaduct height (H) and viaduct breadth (B) were determined from the laser range finder and satellite images, respectively, and the breadth-height ratio (B/H) was calculated.1.0, dPM2.5, dPM10, and dTSP in the UVS sample sites using one-way analysis of variance. We further explored the relationship between the concentration difference of the four particulate matter types and the nine environmental parameters through linear regression analysis [10, PM2.5, and PM1 concentrations in the summer and winter. The prediction model is as follows:1.0, CPM2.5, CPM10, or CTSP; a is a constant; b1, b2, ... bn denote the coefficients of independent variables; and X1, X2, ... Xn are the landscape element parameters. The statistical analysis process was performed using SPSS 22.0 . For the regression analysis results, a p value of <0.05 was considered to be statistically significant.After acquiring the monitoring data, we comparatively analyzed the dPManalysis . Then, t1.0 and TSP reached the peak in the QJSB1 section, whereas those of PM2.5 and PM10 reached the peak in the JXSL1 section. Excluding the QYL2 section, these concentrations of the four particulate matter types exceeded the fixed-point concentrations at the other 13 monitoring points.As shown in 1.0, PM2.5) dPM1.0 was −22.92 μg/m3 and the mean concentration of dPM2.5 was −23.24 μg/m3. Except in the QYL1 section, their mean concentrations at the 13 other sample sites were negative. The mean concentration of the coarse particulate matter  dPM10 was −26.51 μg/m3, and the mean concentration of dTSP was −33.33 μg/m3; the maximum concentrations of both types appeared in the QYL1 section. In the QYL1 section, the concentration difference in coarse particulate matter was maximized and exhibited the most significant variation.In the summer, the mean concentration of the fine particulate matter .We used a linear regression model to visualize the influence of different environmental parameters on particle reductions. These reductions are represented by the net concentration differences of the four types of particulate matter in the summer and winter . The cor10 were both correlated with RH and Aga. Simultaneously, the dPM10 concentration was also correlated with Ta and UVSgw. First, the dTSP concentration was positively correlated with RH (1 = 0.041) in the summer, and it was found that the concentration difference of dTSP decreases with increasing RH. In winter, the dTSP concentration had no significant correlation with RH, but had a strong positive correlation with Aga (2 = 0.009) (note: dTSP did not have a significant correlation with Aga in the summer). Furthermore, the dTSP concentration had no significant correlation with other environmental parameters in the summer or winter. Second, the dPM10 concentration was positively correlated with Ta (1 = 0.022) and RH (1 = 0.009) in the summer, but there was no significant correlation in the winter. The dPM10 concentration was positively correlated with UVSgw (2 = 0.028) and UVSga (2 = 0.023) in the winter, but there was no significant correlation in the summer. dPM10 exhibited no significant correlation with other environmental parameters in summer or winter.As shown in 2.5 and dPM1.0 were both significantly correlated with Ta and RH, respectively, and dPM2.5 and dPM1.0 were correlated with UVSgw and Aod, respectively. The dPM2.5 concentration had a very significant negative correlation with Ta in both summer and winter , but showed a significant positive correlation with RH . The dPM2.5 concentration was positively correlated with UVSgw in the winter, but exhibited no significant correlation in the summer (2 = 0.047). Other environmental parameters were not significantly correlated with the dPM2.5 concentration. In both summer and winter, the dPM1.0 concentration was significantly negatively correlated with Ta , but was significantly positively correlated with RH . Additionally, the dPM1.0 concentration was positively correlated with the Aod in the winter (2 = 0.032). Other environmental parameters were not significantly correlated with the dPM1.0 concentration.As shown in 2) refers to the change ratio of the net concentration difference of each type of particulate matter, as explained by the predictive regression model. The standardization coefficient (beta coefficient) refers to the relative contribution of different environmental parameters to the change in the net concentration difference of particulate matter.Through a multiple linear regression model (backward method), we investigated the effect of different combinations of environmental parameters in the summer and winter on the net concentration difference of the four types of particulate matter in the UVS. The coefficient of determination . The dPM10 concentration was most significantly affected by Aba, and its beta coefficient was 0.630. A 10% increase in Aba would increase the dPM10 concentration by 0.58 μg/m3 in the summer. Finally, approximately 95.9% of the variation in dPM2.5 and dPM1.0 in the summer was jointly explained by three environmental parameters. In the dPM2.5 model, the dPM2.5 concentration was most significantly affected by RH, followed by UVSgw with beta coefficients of 0.957 and −0.626, respectively. According to the dPM2.5 model, a 10% increase in RH would increase the dPM2.5 concentration by 26.44 μg/m3 in the summer (dPM2.5 = −35.385 + 2.644 RH − 1.513 UVSgw + 0.358 Abd). In the dPM1.0 model, the dPM1.0 concentration was most significantly affected by RH, followed by UVSgw with beta coefficients of 0.958 and −0.619, respectively. A 10% increase in RH would increase the dPM2.5 concentration by 25.90 μg/m3 in the summer (dPM1.0 = −34.467 + 2.590 RH − 1.463 UVSgw + 0.353 Abd).First, in summer, approximately 91.0% of the variation in dTSP was jointly explained by four environmental parameters (dTSP = −1711.484 + 33.256 Ta + 11.453 RH − 0.166 UVSga + 87.910 B/H) . The dTS3. Second, approximately 94.1% of the variation in dPM10 in the winter was jointly explained by seven environmental parameters (dPM10 = 4415.145 − 190.056 Ta − 39.637 RH + 77.014 UVSgw − 2.127 UVSga + 3.228 Abd − 2.524 Aod − 170.174 B/H). The dPM10 concentration was most significantly affected by UVSgw, and its beta coefficient was 7.681. A 10% increase in UVSgw would increase the dTSP concentration by 770.14 μg/m3.First, approximately 92.8% of the variation in dTSP in the winter was jointly explained by six environmental parameters (dTSP = 9636.803 − 408.430 Ta − 93.070 RH + 213.995 UVSgw − 6.212 UVSga − 6.816 Aod − 262.021 B/H) . The dTS2.5 regression model, approximately 96.9% of the variation in dPM2.5 in the winter was jointly explained by five environmental parameters  (dPM2.5 = 1527.777 − 67.602 Ta − 11.031 RH + 21.708 UVSgw − 0.585 UVSga + 1.370 Abd − 0.480 Aod − 80.255 B/H). In the winter, the dPM2.5 concentration was most significantly affected by Ta, followed by UVSgw with beta coefficients of −3.550 and 3.522, respectively. A 10% increase in Ta would reduce the dPM2.5 concentration by 676.02 μg/m3. In the dPM1.0 regression model, approximately 94.4% of the variation in dPM1.0 in the winter was jointly explained by five environmental parameters (dPM1.0 = 1252.466 − 53.590 Ta − 9.374 RH + 19.967 UVSgw − 0.585 UVSga − 54.632 B/H). The dPM1.0 concentration was most significantly affected by UVSgw, and its beta coefficient was 4.442. According to the dPM1.0 regression model, a 10% increase in UVSgw would increase the dPM1.0 concentration by 199.67 μg/m3.In the PMMotor vehicle emissions are one of the primary sources of atmospheric particulate pollution in urban areas ,35,36. TThe distribution of particulate matter concentration in urban environments is characterized by spatial and seasonal variations . The resThe concentration of urban airborne particulate matter exhibited a strong correlation with meteorological factors characterized by seasonal variation ,42,43,44Different environmental parameters had varying degrees of effects on particulate matter concentrations. Correlation analysis showed that a single landscape element had relatively slight effects on the particulate matter concentration in UVSs . HoweverSecond, greening structures in UVSs can affect the particulate matter concentration in UVSs. The larger the greening area is, the more significant the absorption and adsorption effects are . AdditioUrban air pollution poses serious environmental health risks and severe threats to humans and ecosystems ,56. PartOptimization of greening structures is an essential measure for improving the environment of UVSs. Excessive greening density in UVSs will hinder particulate matter diffusion  and, theThis study shows that the concentrations of particulate matter of different sizes exhibit spatial and seasonal differences in the UVSs of Wuhan. The mean concentrations of four different types of particulate matter in the winter were significantly higher than those in the summer. Mean concentrations in UVSs were lower than those in adjacent areas in the summer but higher than those in adjacent areas in the winter. Only some of environmental parameters exhibited a minor individual correlation with the particulate matter concentration in UVSs. In contrast, the collective effects of the compound environment, comprising of nine environmental parameters, on the particulate matter concentration in UVSs were significant. In the summer, meteorological factors had dominant effects on the particulate matter concentration in UVSs, while in the winter, greening structures had dominant effects on the particulate matter concentration in UVSs. Additionally, the viaduct structure and ambient built environment can affect the particulate matter concentration in UVSs. Therefore, adjusting and optimizing environmental parameters is essential for reducing particulate pollution in UVSs and has practical significance to the planning of urban viaducts and the design and utilization of UVSs.This study had several limitations owing to constraints related to the number of monitoring samples and measuring instruments. First, the selected sample sites covered the common UVS types observed in Wuhan; however, obtaining accurate regression analysis results requires more sample sites to be monitored. Second, owing to the uncertainty in the microenvironment and data availability regarding particulate matter concentrations and the environment, the interpretation of statistical data contains some inaccuracy. The restrictions imposed by the complexity of the spatiotemporal scale on the scientific interpretation of the correlations between environmental parameters and particulate matter concentrations should also be verified. Further studies should focus on the effects of environmental parameters on the abatement of particulate matter in UVSs and determine a theoretical basis for the sustainable utilization of UVSs.