Adsorptive removal of lead from aqueous solutions by amine–functionalized magMCM-41 as a low–cost nanocomposite prepared from rice husk: Modeling and optimization by response surface methodology

Amorphous silica that was extracted from rice husk was used to synthesize the magMCM-41 mesoporous silica. This was then functionalized by the APTMS group in order to produce NH₂-magMCM-41 as a novel and low–cost adsorbent. The XRD, VSM, N₂ adsorption–desorption, FT–IR, TGA, SEM and TEM analyses were utilized to characterize the produced materials. In order to optimize the adsorption of the Pb(II) ions, the RSM (response surface methodology) was applied by using the synthesized adsorbent in aqueous solutions. A rotatable CCD (central composite design) was adopted to carry out the experiments and RSM was used to analyze them. Three independent factors namely, initial solution pH (3–7), adsorbent dosage (0.1–2 g L^?1), and initial Pb(II) concentration (15–150 mg L^?1) were used to investigate the removal procedure. According to the obtained results, the initial solution pH of 5.22, adsorbent dosage of 0.1 g L^?1, and initial Pb(II) concentration of 150 mg L^?1 were considered as the optimum conditions with 64.32% removal of Pb(II) and an adsorption capacity of 540.64 mg g^?1. The maximum removal efficiency of Pb(II) ions was found to be 96.76%. The Sips isotherm model represents a better correlation with equilibrium data. It was reported by the kinetic study that data taken from the experiments fitted better to the pseudo–second–order model compared to the pseudo–first–order and intraparticle diffusion models. Finally, according to the thermodynamic study, the removal process strongly depends on temperature, which indicates an exothermic behavior and spontaneous nature of the adsorption.     

Predictors of Weight Regain and Insufficient Weight Loss According to Different Definitions After Sleeve Gastrectomy: a Retrospective Analytical Study

Background

Weight regain (WR) and insufficient weight loss (IWL) after sleeve gastrectomy (SG) are challenging issues. This study aimed to evaluate the predictors of WR and IWL after SG.

Methods

In this retrospective analytical study, 568 patients who underwent SG at Hazrat-e Rasool General Hospital, Tehran, Iran, between January 2015 and April 2022 were evaluated. A total of 333 patients were included. WR and IWL were evaluated by multiple criteria such as a BMI of > 35 kg/m², an increase in BMI of > 5 kg/m² above nadir, an increase in weight of > 10 kg above nadir, percentage of excess weight loss (%EWL) < 50% at 18 months, an increase in weight of > 25% of EWL from nadir at 36 months, and percentage of total weight loss (%TWL) < 20% at 36 months. All participants were followed up for 36 months.

Result

The univariate analysis showed that preoperative BMI, obstructive sleep apnea, metformin consumption, and grades 2 and 3 fatty liver disease were associated with WR and IWL (P < 0.05). WR or IWL incidence varied (0–19.3%) based on different definitions. The multivariate analysis showed that a preoperative BMI of > 45 kg/m² [odds ratio_Adjusted (OR_Adj) 1.77, 95% CI: 1.12–4.11, P = 0.038] and metformin consumption [OR_Adj: 0.48, 95% CI: 0.19–0.78, P = 0.001] were associated with WR and IWL after SG, regardless of the definition of WR or IWL.

Conclusion

This study showed that preoperative BMI of > 45 kg/m², obstructive sleep apnea, metformin consumption, and grades 2 and 3 of fatty liver disease were associated with WR or IWL.

Graphical abstract

     

Ten Years’ Experience in Surgical Treatment of Right Middle Lobe Syndrome

Purpose: In this study we present the clinical, radiological, pathological, bronchoscopic and surgical results of 40 patients with diagnosis of middle lobe syndrome who were referred to our thoracic surgery unit for surgical intervention in a 10 years period.Methods: Forty patients with obstructive and non-obstructive causes of middle lobe syndrome referred to our thoracic surgery unit. Clinical data were collected from the patients’ records in a ten years period. This study evaluates diagnostic approaches and surgical treatments in right middle lobe syndrome.Results: We studied 23 females (57.5%) and 17 males (42.5%) with a mean age of 31.7. Clinical findings were cough 95%, sputum 80% and intermittent hemoptysis in 50% of patients. Middle lobe collapse was seen in CT scan of all patients. Bronchiectasis was the most common pathologic finding (55%). Tuberculosis was not rare and was final pathology in 20% of patients. In three patients ruptured hydatid cyst was final finding. Surgery was done without mortality and with only minor complications.Conclusion: Lobectomy of right middle lobe is a good therapeutic option in these patients. Due to high prevalence of tuberculosis and hydatid cyst in Middle Eastern countries these two must be considered as causes of middle lobe syndrome.     

The effect of indomethacin on alveolar bone loss in experimental periodontitis

This study was undertaken to determine if prostaglandins play a role in the events leading to loss of bone in the ligature model of periodontitis. Periodontitis was induced by placement of the ligatures around mandibular teeth on one side of the jaw of squirrel monkeys ( Saimiri sciureus ). From one day prior to ligature placement, half the animals were administered indomethacin (5 mg/kg/day), a potent inhibitor of prostaglandin synthesis. Animals were sacrificed after one and two weeks of experimental periodontitis. It was found that indomethacin treatment abolished the significant losses of alveolar bone height and bone mass seen in non-indomethacin-treated (NIT) animals following ligature placement. Indomethacin also depressed the large increase in osteoclast density measured at one week in the NIT animals. The results support the hypothesis that prostaglandins are an important mediator of bone loss in the ligature model of periodontitis. Evidence is also presented for the coupling of bone resorption with osteoblastic neo-osteogenesis on both periodontal ligament and endosteal bone surfaces.     

The effects of verapamil and heparin co-administration on sperm parameters and oxidative stress in prevention of testicular torsion/detorsion damage in rats

In this research, the impacts of combined administration of verapamil and heparin on testicular torsion damage were examined. In this experimental study, 30 sexually mature male Wistar albino rats were divided into five equal groups haphazardly (n = 6): Group 1 was the sham group. In group 2, a 2-hr testicular torsion was induced, and thereafter, detorsion was done. Rats in group 3 and group 4 experienced an identical surgical procedure like group 2, but verapamil and heparin were administered in 0.3 mg/kg and 800 IU/kg doses respectively, and in group 5, a combination of verapamil and heparin were administered. Intraperitoneal drug injection in all treatment groups was done 30 min before testicular detorsion. Testicular torsion significantly changed sperm parameters, oxidative stress biomarkers and Cosentino's histological score compared to the sham group (p < .05). All treatment groups reduced testicular damage by decreasing oxidative stress and improving sperm parameters, but heparin and co-administration of verapamil and heparin were significantly better than verapamil injection alone. However, heparin injected group was more effective than other treatment groups (p < .05). Overall, an anticoagulant like heparin is more effective than a calcium channel blocker such as verapamil, and it is more likely to reduce testicular torsion injuries.     

Toward Semi-autonomous Cryoablation of Kidney Tumors <Emphasis Type="Italic">via</Emphasis> Model-Independent Deformable Tissue Manipulation Technique

We present a novel semi-autonomous clinician-in-the-loop strategy to perform the laparoscopic cryoablation of small kidney tumors. To this end, we introduce a model-independent bimanual tissue manipulation technique. In this method, instead of controlling the robot, which inserts and steers the needle in the deformable tissue (DT), the cryoprobe is introduced to the tissue after accurate manipulation of a target point on the DT to the desired predefined insertion location of the probe. This technique can potentially reduce the risk of kidney fracture, which occurs due to the incorrect insertion of the probe within the kidney. The main challenge of this technique, however, is the unknown deformation behavior of the tissue during its manipulation. To tackle this issue, we proposed a novel real-time deformation estimation method and a vision-based optimization framework, which do not require prior knowledge about the tissue deformation and the intrinsic/extrinsic parameters of the vision system. To evaluate the performance of the proposed method using the da Vinci Research Kit, we performed experiments on a deformable phantom and an ex vivo lamb kidney and evaluated our method using novel manipulability measures. Experiments demonstrated successful real-time estimation of the deformation behavior of these DTs while manipulating them to the desired insertion location(s).     

Identification of Potential Biomarkers in the Peripheral Blood Mononuclear Cells of Relapsing–Remitting Multiple Sclerosis Patients

Inflammation - Multiple&nbsp;sclerosis&nbsp;(MS)&nbsp;is described as an immune disorder with inflammation and neurodegeneration. Relapsing–remitting MS (RRMS) is one of the most...     

Cluster of Middle East Respiratory Syndrome Coronavirus Infections in Iran, 2014

During January 2013–August 2014, a total of 1,800 patients in Iran who had respiratory illness were tested for Middle East respiratory syndrome coronavirus. A cluster of 5 cases occurred in Kerman Province during May–July 2014, but virus transmission routes for some infections were unclear.     

Case report: Cavitation of mesenteric lymph nodes as the presenting feature of coeliac disease

Cystic cavitation of the lymph nodes associated with hyposplenism is a rare and under‐recognised complication of coeliac disease. This report encompasses the clinical, radiological and pathological features of this condition, while demonstrating the pivotal role radiological imaging plays in achieving a clinical diagnosis.