Clinical Outcomes Following Postoperative Cavity Stereotactic Radiosurgery for Brain Metastases

PURPOSE/OBJECTIVE(S)

We evaluated outcomes of patients with brain metastases (BM) treated with surgical resection and postoperative cavity stereotactic radiosurgery (SRS) to identify which baseline characteristics and treatment factors may increase risk for local recurrence (LR).

MATERIALS/METHODS

From June 2017 to December 2021, 68 patients underwent surgical resection for BM followed by single-fraction SRS (n = 15) or fractionated SRS (FSRS) in 3 (n = 24) or 5 (n = 29) fractions to the postoperative cavity using frameless LINAC-based technique. Patients treated with surgery alone or surgery with postoperative whole brain radiotherapy (WBRT) were excluded. Median prescription doses were 1600 cGy (range: 1440-1875) in 1 fraction, 2400 cGy (range: 2100-2700) in 3 fractions, and 3000 cGy (range: 2500-3000) in 5 fractions. Local control (LC) and overall survival (OS) were estimated by the Kaplan-Meier method. Cox proportional hazards models were used to compare groups.

RESULTS

Median follow-up was 19.5 months (IQR: 9.0-34.7). Median patient age was 62.5 years (range: 24-80), and 38 (55.9%) patients were male. Primary tumors were lung (n = 29), including NSCLC (n = 28) and SCLC (n = 1), melanoma (n = 12), breast (n = 11), and other (n = 16). Median preoperative tumor maximal dimension was 3.5cm (range: 1.1-6.3). Median planning treatment volume (PTV) was larger in the FSRS group (26.2cc (range: 6.5-151.8)) than in the SRS group (7.7cc (range: 1.1-11.5)) (p<0.001). Median number of concurrently treated intact lesions was 0 (range: 0-13). Median time from surgery to SRS was 32 days (range: 14-77). Forty-eight (70.6%) patients were treated with immunotherapy or targeted therapy. Median OS was 22.3 months (95% CI: 14.4-30.9). The 1-year and 2-year OS rates were 70% and 48%, respectively. The 1-year and 2-year LC rates were 86% and 73%, respectively. Median time to LR was 8.4 months (95% CI: 4.4-11.0). Among the 14 patients with LR, 11 had undergone salvage therapy at last follow-up which included repeat SRS (n = 4), WBRT (n = 3), palliative local radiotherapy (n = 2), surgery followed by repeat SRS (n = 1), and systemic therapy (n = 1). Eleven (16.2%) patients ultimately underwent WBRT post-SRS for local and/or distant failure. No difference in LC was observed based on primary tumor, time interval between resection and SRS, PTV volume, prescription dose, or fractionation regimen (SRS v. FSRS). However, all LR in the 3-fraction group occurred in patients who received less than 2700 cGy.

CONCLUSION

Favorable LC and OS outcomes were observed following postoperative cavity SRS for resected BM in a modern cohort with a large percentage of patients receiving immunotherapy or targeted therapy. No prognostic factors were identified for LC which may be attributable to the cohort size and small number of events observed. However, our findings suggest that patients who undergo 3-fraction FSRS should be treated to a total dose of 2700 cGy to maximize LC.

The impact of meteorological parameters on PM10 and visibility during the Middle Eastern dust storms

Air pollution is one of the most pressing issues in populated Middle Eastern cities, in particular for the city of Ahvaz, Iran, imposing deleterious effects on the environment, public health, economy, culture, and other sectors. In this study, we investigate the relationship between meteorological parameters, PM₁₀, AOD, air mass source origin, and visibility during severe desert dust storms (Average_3h PM₁₀ > 3200 µg m^-3) between 2009 and 2012. Six of seven such events occurred between February and March. Interestingly, for the seven cases there was always an alarming PM₁₀ mass concentration peak (137-553 µg m^-3) between 12:00-18:00 (local time) that was 18-24 h before the dominant peak of the storm (3279-4899 µg m^-3). The maximum wind speed over the multi-day periods examined for the dust storms is usually observed 6 h before the alarming PM₁₀ peak. The minimum relative humidity, dew point temperature and air pressure occurred ± 3 h around the time of the alarming PM₁₀ peak. Wind speed was the meteorological parameter that was consistently higher around the time of the first peak as compared to the second peak, with the reverse being true for sea level pressure. Based on four years of daily data in Ahvaz, PM₁₀ was positively correlated with wind speed and air temperature and inversely correlated with sea level pressure and RH. An empirically-derived equation with R² = 0.95 is reported to estimate the maximum PM₁₀ concentration for severe desert dust events in the study region based on meteorological parameters. Finally, AOD is shown to correlate strongly (R² = 0.86) with PM₁₀ during periods with severe desert dust storms in the region.

POS0231 GENETIC BIOMARKERS, SNP GENES AND mtDNA HAPLOGROUPS, PREDICT OSTEOARTHRITIS STRUCTURAL PROGRESSORS THROUGH THE USE OF SUPERVISED MACHINE LEARNING

Background

Knee osteoarthritis is the most prevalent chronic musculoskeletal debilitating disease. Current treatments are only symptomatic and to improve this, we need a robust prediction model to stratify patients at an early stage according to the risk of joint structure disease progression. Some genetic factors, including single nucleotide polymorphism (SNP) genes and mitochondrial (mt)DNA haplogroups/clusters, have been linked to this disease.

Objectives

For the first time, we aim to determine, by using machine learning, whether some SNP genes and mtDNA haplogroups/clusters alone or combined could predict early knee osteoarthritis structural progressors.

Methods

Participants (901) were first classified for the probability of being structural progressors. Genotyping included SNP genes TP63, FTO, GNL3, DUS4L, GDF5, SUPT3H, MCF2L, TGFA, mtDNA haplogroups H, J, T, Uk, others, and clusters HV, TJ, KU, C-others. They were considered for prediction with major risk factors of osteoarthritis, namely, age and body mass index (BMI). Seven supervised machine learning methodologies were evaluated. The support vector machine was used to generate gender-based models. The best input combination was assessed using sensitivity and synergy analyses. Validation was performed using 10-fold cross-validation as well as an external cohort (TASOAC).

Results

From 277 models, two were defined. Both used age and BMI in addition for the first one of the SNP genes TP63, DUS4L, GDF5, FTO with an accuracy of 85.0%; the second profits from the association of mtDNA haplogroups and SNP genes FTO and SUPT3H with 82.5% accuracy. The highest impact was associated with the haplogroup H, the presence of CT alleles for rs8044769 at FTO, and the absence of AA for rs10948172 at SUPT3H. Validation accuracy with the cross-validation (about 95%) and the external cohort (90.5%, 85.7%, respectively) was excellent for both models.

Conclusion

This study introduces a novel source of decision support in precision medicine in which, for the first time, two models were developed consisting of i) age, BMI, TP63, DUS4L, GDF5, FTO and ii) the optimum one as it has one less variable: age, BMI, mtDNA haplogroup, FTO, SUPT3H. Such a framework is translational and would be of benefit to patients at risk of structural progressive knee osteoarthritis.

Acknowledgements

The authors would like to thank the Osteoarthritis Initiative (OAI) participants and Coordinating Center for their work in generating the clinical and radiological data of the OAI cohort and for making them publicly available. The OAI is a public-private partnership comprised of five contracts (N01-AR-2-2258; N01-AR-2-2259; N01-AR-2-2260; N01-AR-2-2261; N01-AR-2-2262) funded by the National Institutes of Health, a branch of the Department of Health and Human Services, and conducted by the OAI Study Investigators. Private funding partners include Merck Research Laboratories; Novartis Pharmaceuticals Corporation, GlaxoSmithKline; and Pfizer, Inc. Private sector funding for the OAI is managed by the Foundation for the National Institutes of Health. This manuscript was prepared using an OAI public use data set and does not necessarily reflect the opinions or views of the OAI investigators, the NIH, or the private funding partners. None of the authors are part of the OAI investigator team. Moreover, the authors are also grateful to the TASOAC participants.

A special thanks to ArthroLab Inc. for having provided the MRI data used for classifying structural progressors for each individual.

Disclosure of Interests

Hossein Bonakdari: None declared, Jean-Pierre Pelletier Shareholder of: ArthroLab Inc., Grant/research support from: Work supported in part by the Osteoarthritis Research Unit of the University of Montreal Hospital Research Centre and the Chair in Osteoarthritis from the University of Montreal., Francisco J. Blanco: None declared, Ignacio Rego-Perez: None declared, Alejandro Durán-Sotuela: None declared, Dawn Aitken: None declared, Graeme Jones: None declared, Flavia Cicuttini: None declared, Afshin Jamshidi Grant/research support from: Received a bursary from the Canada First Research Excellence Fund through the TransMedTech Institute in Canada., François Abram Employee of: was an employee of ArthroLab Inc., Johanne Martel-Pelletier Shareholder of: ArthroLab Inc., Grant/research support from: Work supported in part by the Osteoarthritis Research Unit of the University of Montreal Hospital Research Centre and the Chair in Osteoarthritis from the University of Montreal.

Radial Long Sheath Angioplasty for Proximal Severe Flow Limiting Radial Artery Spasm Utilizing the Dotter Technique

BACKGROUND

Although studies continue to demonstrate the advantages of transradial access (TRA) for neurointerventions, radial artery spasm (RAS) remains a frequent cause of TRA failure. Dotter initially described a technique to dilate areas of peripheral vascular stenosis by advancing sequentially larger catheters across the lesion over a wire. We present our institutional experience performing a modified Dotter technique utilizing long radial sheaths to dilate areas of proximal flow limiting RAS.

OBJECTIVE

To review the use of the Dotter technique for alleviating RAS in patients undergoing TRA for neurointerventions.

METHODS

A retrospective review of all patients undergoing TRA for neurointerventions at our institution from 2018-2020 was performed to identify patients with proximal flow limiting RAS. In identified patients, a modified Dotter technique was employed to dilate the stenosis. Demographic and periprocedural data were assessed to identify any adverse outcomes.

RESULTS

Four patients with severe proximal flow limiting RAS were identified. In each case, a hydrophilic long radial sheath and vascular dilator were sequentially advanced through the stenosis. In all cases, repeat angiography demonstrated improvement of the spasm and final radial angiograms demonstrated persistent improvement in caliber and regularity of the vessel. Each procedure was also completed via TRA with no periprocedural complications.

CONCLUSIONS

Our modified Dotter technique is effective in bypassing areas of severe proximal flow limiting RAS thus obviating the need for access site conversion. Additional studies are warranted to understand the implication of the angioplasty-like effects seen within the radial artery following removal of the long radial sheaths.

Clinical validation of a targeted methylation-based multi-cancer early detection test using an independent validation set

BACKGROUND

A multi-cancer early detection (MCED) test used to complement existing screening could increase the number of cancers detected through population screening, potentially improving clinical outcomes. The Circulating Cell-free Genome Atlas study (CCGA; NCT02889978) was a prospective, case-controlled, observational study and demonstrated that a blood-based MCED test utilizing cell-free DNA (cfDNA) sequencing in combination with machine learning could detect cancer signals across multiple cancer types and predict cancer signal origin (CSO) with high accuracy. The objective of this third and final CCGA substudy was to validate an MCED test version further refined for use as a screening tool.

PATIENTS AND METHODS

This pre-specified substudy included 4077 participants in an independent validation set (cancer: n = 2823; non-cancer: n = 1254, non-cancer status confirmed at year-one follow-up). Specificity, sensitivity, and CSO prediction accuracy were measured.

RESULTS

Specificity for cancer signal detection was 99.5% [95% confidence interval (CI): 99.0% to 99.8%]. Overall sensitivity for cancer signal detection was 51.5% (49.6% to 53.3%); sensitivity increased with stage [stage I: 16.8% (14.5% to 19.5%), stage II: 40.4% (36.8% to 44.1%), stage III: 77.0% (73.4% to 80.3%), stage IV: 90.1% (87.5% to 92.2%)]. Stage I-III sensitivity was 67.6% (64.4% to 70.6%) in 12 pre-specified cancers that account for approximately two-thirds of annual USA cancer deaths and was 40.7% (38.7% to 42.9%) in all cancers. Cancer signals were detected across >50 cancer types. Overall accuracy of CSO prediction in true positives was 88.7% (87.0% to 90.2%).

CONCLUSION

In this pre-specified, large-scale, clinical validation substudy, the MCED test demonstrated high specificity and accuracy of CSO prediction and detected cancer signals across a wide diversity of cancers. These results support the feasibility of this blood-based MCED test as a complement to existing single-cancer screening tests.

CLINICAL TRIAL NUMBER

NCT02889978.

Water quality evaluation and non-cariogenic risk assessment of exposure to nitrate in groundwater resources of Kamyaran, Iran: spatial distribution, Monte-Carlo simulation, and sensitivity analysis

Water is exceptionally vital for all living beings and socio-economic development. This study aimed to investigate the groundwater suitability for drinking in rural areas of Kamyaran city, Kurdistan province, Iran, by using the water quality index (WQI) and evaluating the non-carcinogenic health risk caused by nitrate from the drinking route. Forty-five groundwater samples were collected (2019) from operated dug-wells, and twelve parameters (TDS, pH, TH, EC, HCO3 -, K+, Na+, Mg2+, Ca2+, Cl-, SO4 2-, and NO3 -) were measured to the calculation of WQI. Hazard Quotient (HQ) and sensitivity analysis (SA) using the Monte-Carlo Simulation technique with 10,000 iterations were employed to determine the non-carcinogenic effects of Nitrate in different exposed groups (Infant, children, teenagers, and adults). The results of WQI showed that 74% of groundwater samples fall within the excellent water quality class, and 26% of rural areas fall in the category of good water type. The nitrate concentration in drinking water ranged from 22.42 ± 11.44 mg/L. The HQ mean for infants, children, teenagers, and adults were 0.5606, 0.7288, 0.5606, and 0.438, respectively. Probability estimation showed the HQ values for the 5th, and 95th percentile in infants, children, teenagers, and adult groups were (0.25-1.81), (0.13-1.08), (0.13-0.97), and (0.07-0.51), respectively. The SA showed that the most significant parameter of non-carcinogenic risk in all exposed populations was nitrate concentration. Generally, nitrate concentration in the study area was relatively high, and remarkably in agriculture and fertilizer management required more attention.

Effect of COVID-19 pandemic on medical waste management: a case study

Covid-19 Pandemic leads to medical services for the society all over the world. The Covid-19 pandemic influence the waste management and specially medical waste management. In this study, the effect of the Covid-19 outbreak on medical waste was evaluated via assessing the solid waste generation, composition, and management status in five hospitals in Iran. The results indicated that the epidemic Covid-19 leads to increased waste generation on average 102.2 % in both private and public hospitals. In addition, the ratio of infectious waste in the studied hospitals increased by an average of 9 % in medical waste composition and 121 % compared with before COVID-19 pandemic. Changes in plans and management measurement such as increasing the frequency of waste collection per week leads to lower the risk of infection transmission from medical waste in the studied hospitals. The results obtained from the present research clearly show the changes in medical waste generation and waste composition within pandemic Covid-19. In addition, established new ward, Covid-19 ward with high-infected waste led to new challenges which should be managed properly by change in routine activities.

Molecular typing and prevalence of extended-spectrum β-lactamase genes in diarrhoeagenic Escherichia coli strains isolated from foods and humans in Mashhad, Iran

AIMS

Present study was aimed to determine ESBL-encoding genes distribution in Diarrhoeagenic Escherichia coli (DEC) isolated from animal-source food products and human clinical samples in Mashhad, Iran. The strains were also further studied to analyse genotypic diversity and find genetic relationships between them.

METHODS AND RESULTS

The number of 85 DEC strains including 52 and 33 strains isolated from 300 food and 520 human stool samples, respectively. Randomly amplified polymorphic DNA (RAPD), and repetitive extragenic palindromic-PCR (rep-PCR) typing methods were used to track their genetic relationships. The ESBL-encoding genes prevalence was approximately 70% in both groups of isolates. The bla_TEM , bla_CTX-M and bla_SHV were prevalent in 67·1, 20 and 10·6% of isolates, respectively. The ESBL-positives showed significantly higher resistance rates to gentamicin, co-trimoxazole, tetracycline, aztreonam and chloramphenicol (P < 0·05). Fingerprinting patterns-based dendrograms divided DEC strains into separate clusters irrespective of their sources and pathotypes. In typing field, rep-PCR provided more discriminatory power (Simpson's index of diversity (SID) = 0·925) than RAPD (SID = 0·812).

CONCLUSION

Molecular similarity between certain animal-sourced food products and clinical sample strains supported food-borne transmission routes for genotypic elements such as ESBL-encoding genes.

SIGNIFICANCE AND IMPACT OF THE STUDY

Findings emphasize the importance of resistance issues, the need to improve treatment guidelines and routine surveillance of hygienic measures during food processing.

FRI0417 IDENTIFICATION OF THE MOST IMPORTANT FEATURES OF KNEE OSTEOARTHRITIS PROGRESSORS USING MACHINE LEARNING METHODS

Background:

Knee osteoarthritis (OA), a leading cause of disability worldwide, can be difficult to define as its development is often insidious and involves different subgroups. We still lack robust prediction models that are able to guide clinical decisions and stratify OA patients according to risk of disease progression.

Objectives:

This study aimed at identifying the most important features of knee OA progressors. To this end, we used machine learning (ML) algorithms on a large set of subjects and features to develop advanced prediction models that provide high classification and prediction performance.

Methods:

Participants, features and outcomes were from the Osteoarthritis Initiative. Features were from baseline (1107), including articular knee tissues (135) assessed by quantitative MRI. OA progressors were ascertained by four outcomes: cartilage volume loss in medial plateau at 48 and 96 months (Prop_CV_48M, 96M); Kellgren-Lawrence (KL) grade ≥2; and medial joint space narrowing (JSN) ≥1 at 48 months. Subjects’ numbers were as follows: 1598 for the outcome Prop_CV_96M, 1044 for the Prop_CV_48M, and 1468 for each KL grade ≥2 at 48 months and JSN ≥1 at 48 months. Six feature selection models were used to identify the common features in each outcome. Six classification methods were applied to measure the accuracy of the selected features in classifying the subjects into progressors and non-progressors. Classification of the best features was done using auto-ML interface and the area under the curve (AUC). To prioritize the top features, Sparse Partial Least Square (sPLS) method was used.

Results:

For the classification of the best common features in each outcome, Multi-Layer Perceptron (MLP) achieved the highest AUC in Prop_CV_96M, KL, and JSN (0.80, 0.88, 0.95), and Gradient Boosting Machine (GBM) for Prop_CV_48M (0.70). sPLS revealed that the baseline top five features to predict knee OA progressors are the joint space width (JSW), mean cartilage thickness of peripheral, medial, and central tibial plateau, and JSN.

Conclusion:

This is the first time that such a comprehensive study was performed for identifying the best features and classification methods for knee OA progressors. Data revealed that early prediction of knee OA progression can be done with high accuracy and based on only a few features. This study identifies the baseline X-ray and MRI-based features as the most important for predicting knee OA progressors. These results could be used for the development of a tool enabling prediction of knee OA progressors.

Acknowledgments:

This work was supported in part by the Osteoarthritis Research Unit of the University of Montreal Hospital Research Centre; the Chair in Osteoarthritis, University of Montreal, (both from Montreal, Quebec, Canada); and the Computational Biology Laboratory, Laval University Hospital Research Center, (Québec, Quebec, Canada). A Jamshidi received a bursary from the Canada First Research Excellence Fund through TransMedTech Institute, (Montreal, Quebec, Canada).

Disclosure of Interests:

Afshin Jamshidi: None declared, Mickaël Leclercq: None declared, Aurelie Labbe: None declared, Jean-Pierre Pelletier Shareholder of: ArthroLab Inc., Grant/research support from: TRB Chemedica, Speakers bureau: TRB Chemedica and Mylan, François Abram Employee of: ArthroLab Inc., Arnaud Droit: None declared, Johanne Martel-Pelletier Shareholder of: ArthroLab Inc., Grant/research support from: TRB Chemedica

Coagulating potential of Iranian oak (Quercus Branti) extract as a natural coagulant in turbidity removal from water

Because of the presence of tannin in the molecular structure of oak extract, this substance is used as a natural coagulant to remove turbidity from water. The aim of this study was to determine the efficiency of this coagulant alone and in combination with polyaluminium chloride (PACl) in turbidity removal from water under optimal conditions. In this experimental study, Iranian oak extract was prepared by maceration method using ethanol 96% as an extractor. Kaolin was used to prepare synthetic turbid water samples. Using the jar test, the optimum concentrations of oak extract and PACl were determined in various concentrations of initial turbidity and pH. Moreover, the central composite design (CCD) method was utilized to design experiments and RSM was applied for analyzing the obtained results. Optimum concentrations of oak extract and PACl were 62.6 mg/L and 52.6 mg/L, respectively. An increase in initial turbidity and pH led to an increase in turbidity removal by the two coagulants. The efficiency of turbidity removal by oak extract and PACl was 63.5% and 66.5%, respectively. The simultaneous application of oak extract and polyaluminium chloride increased removal efficiency (85%) and reduced the total organic carbon concentration (TOC) in water (42.3%). The results showed that the simultaneous application of Iranian oak extract and polyaluminium chloride had an acceptable performance in removing turbidity from water.

A high-flux P84 polyimide mixed matrix membranes incorporated with cadmium-based metal organic frameworks for enhanced simultaneous dyes removal: Response surface methodology

The water sources contaminated by toxic dyes would pose a serious problem for public health. In view of this, the development of a simple yet effective method for removing dyes from industrial effluent has attracted interest from researchers. In the present work, flat sheet mixed matrix membranes (MMMs) with different physiochemical properties were fabricated by blending P84 polyimide with different concentrations of cadmium-based metal organic frameworks (MOF-2(Cd)). The resultant membranes were then used for simultaneous removal of eosin y (EY), sunset yellow (SY) and methylene blue (MB) under various process conditions. The findings indicated that the membranes could achieve high water permeability (117.8-171.4 L/m².h.bar) and promising rejection for simultaneous dyes removal, recording value of 99.9%, 81.2% and 68.4% for MB, EY and SY, respectively. When 0.2 wt% MOF-2(Cd) was incorporated into the membrane matrix, the membrane separation efficiency was improved by 110.2% and 213.3% for EY and SY removal, respectively when compared with the pristine membrane. In addition, the optimization and modeling of membrane permeate flux and dye rejection was explored using response surface methodology. The actual and model results are in good agreement with R² of at least 0.9983 for dye rejection and permeate flux. The high flux of the developed MMMs coupled with effective separation of dyes suggests a promising prospect of using P84 polyimide MMMs incorporated with MOF-2(Cd) for water purification.

Resolution of bilateral sensorineural hearing loss following ventriculoperitoneal shunt and literature review

OBJECTIVE

The purpose of this study is to highlight the relationship between obstructive hydrocephalus, changes in intracranial pressure, and sensorineural hearing loss.

METHODS

A case of a 10-month old infant with sensorineural hearing loss secondary to obstructive hydrocephalus is reported. A literature review, with a focus on sensorineural hearing loss in the setting of changes in intracranial pressure, was performed.

RESULTS

The authors report the case of a 10-month old infant with metopic and bicoronal craniosynostosis who presented with bilateral moderately severe sensorineural hearing loss after failing newborn hearing screening. Imaging subsequently demonstrated obstructive hydrocephalus, which was treated with the insertion of a VP shunt. The patient had immediate improvement of her hearing post-operatively, with repeat hearing tests showed resolution of her hearing loss.

CONCLUSION

Sensorineural hearing loss is a rare complication of hydrocephalus, but changes in intracranial pressure should be considered in the differential diagnosis. We put forth a flow diagram illustrating the hypothesized relationship between intracranial pressures, alterations in the levels of cochlear fluid, and hearing.

Toxigenic Clostridium difficile in retail packed chicken meat and broiler flocks in northeastern Iran

This study was designed to evaluate the occurrence of Clostridium difficile in both broiler chicken farms and packed chicken parts sold at market places in Mashhad, the second most popular Islamic pilgrimage city after Mecca in northeastern Iran. The fresh faecal samples were obtained from broiler farms, while the chicken packs were purchased from retail outlets across the city at market places and samples were obtained from the necks, thighs, and wings. The selective culture was used for isolation of C. difficile. Out of 40 pooled fresh faecal and 65 packed chicken samples, 14 (35%) and 10 (15.3%) samples were positive, respectively. Some of the C. difficile isolates from chickens packs (7 out of 10, 70%) and faecal samples (5 out of 14, 36%) were detected as toxigenic (A, B and binary toxins) using molecular identification. From 14 isolates of the faecal samples, five isolates were tcdA and tcdB positive, and none was binary toxin positive. The results of the present study suggest that broiler chickens are a potential source of C. difficile, which may infect humans through contact or consumption of chicken meat, although the significance of food contamination is entirely unclear, the role of poultry products as a potential source of the infection should be investigated.

pH-Sensitive IPN Hydrogel Beads of Carrageenan-Alginate for Controlled Drug Delivery

Interpenetrating polymer network (IPN) hydrogel beads of carrageenan-sodium alginate (Caralgi) were prepared under mild conditions. Betamethasone acetate, as a water-soluble drug model, was simultaneously loaded while the hydrogel network was being formed. The effect of pH and temperature of the preparative media on the drug loading efficiency was investigated. Maximum loading efficiency (71%) was achieved at pH 4.8 and 55°C. The chemical structure and morphology of the Caralgi IPN hydrogels with and without drug were studied using FTIR and SEM analyses. The system exhibited a loading efficiency that depended on the pH and temperature. The in vitro release behavior by Caralgi IPN samples, prepared under various conditions, was evaluated and compared with that of the non-IPN alginate-Ca2+ and carrageenan-K + hydrogels at pH 1.2 and 7.4.

Preparation and characterization of an AC–Fe3O4–Au hybrid for the simultaneous removal of Cd2+, Pb2+, Cr3+and Ni2+ions from aqueous solution via complexation with 2-((2,4-dichloro-benzylidene)-amino)-benzenethiol: Taguchi optimization

Activated carbon (AC) was magnetized with Fe₃O₄nanoparticles (AC–Fe₃O₄-NPs), loaded with Au nanoparticles (AC–Fe₃O₄–Au-NPs), modified with DBABT and applied for the ultrasound-assisted removal of Cd²⁺, Pb²⁺, Cr³⁺and Ni²⁺ionsviacomplexation with DBABT.

Optimization of the process parameters for the adsorption of ternary dyes by Ni doped FeO(OH)-NWs–AC using response surface methodology and an artificial neural network

The present study deals with the simultaneous removal of chrysoidine G (CG), rhodamine B (RB) and disulfine blue (DB) by Ni doped ferric oxyhydroxide FeO(OH) nanowires on activated carbon (Ni doped FeO(OH)-NWs–AC).

Genomic diversity of Clostridium perfringens strains isolated from food and human sources

Clostridium perfringens is a serious pathogen which causes enteric diseases in domestic animals and food poisoning in humans. Spores can survive cooking processes and play an important role in the possible onset of disease. In this study, RAPD-PCR and REP-PCR were used to examine the genetic diversity of 49 isolates of C. perfringens type A from three different sources. The results of RAPD-PCR revealed the most genetic diversity among poultry isolates, while human isolates showed the least genetic diversity. Cluster analysis obtained from RAPD-PCR and based on the genetic distances split the 49 strains into five distinct major clusters (A, B, C, D, and E). Cluster A and C were composed of isolates from poultry meat, cluster B was composed of isolates from human stool, cluster D was composed of isolates from minced meat, poultry meat and human stool and cluster E was composed of isolates from minced meat. Further characterization of these strains by using (GTG) 5 fingerprint repetitive sequence-based PCR analysis did not show further differentiation between various types of strains. In conclusion, RAPD-PCR method seems to be very promising for contamination source tracking in the field of food hygiene.

Prevention of fluid effusion in kidney transplantation with the use of hemostatic biomaterials

BACKGROUND

Fluid effusion (blood, lymph, or urine) in kidney transplantation may give rise to several complications, directly, such as hematoma, seroma, lymphocele, and/or urinoma, or consequently, such as increased infection risk, longer hospital stay, graft compression--with or without functional impairment--and necessity of further hospitalizations. The aim of this study was to evaluate effectiveness of hemostatic biomaterials in prevention of fluid effusions, especially lymphocele in kidney transplant patients.

METHODS

We selected 40 patients who underwent kidney transplantation from 2009 to 2012 in which we used hemostatic biomaterials, and compared their results with those of other transplant patients from our center in which we did not used these biomaterials. Evaluated parameters were: fluid effusion, graft function, quality and quantity of drainage, blood count, and operative time.

RESULTS

There was no difference in operative time. The incidence of complications on which biomaterials can have a role decreased; particularly, we observed a reduction from 24.21% to 7.5% of fluid effusions (lymphocele). There was no evidence of complications due to biomaterials.

CONCLUSIONS

Hemostasis is important in surgery, and in kidney transplantations lymphostasis also has a significant role. In addition to the traditional hemostatic methods, recently some biomaterials, with the purpose of providing atraumatic hemostasis, were added. In our experience they are easy to use, and their use has proved to be effective for both hemostasis and lymphostasis with consequent reduction of fluid effusions.