Quantitative mechanisms of cadmium adsorption on rice straw- and swine manure-derived biochars

Abstract

We quantified and investigated mechanisms for Cd²⁺ adsorption on biochars produced from plant residual and animal waste at various temperatures. Ten biochars were produced by pyrolysis of rice straw (RB) and swine manure (SB) at 300–700 °C and characterized. The Cd²⁺ adsorption isotherms, adsorption kinetics, and desorption characteristics were studied via a series of batch experiments, and Cd²⁺-loaded biochars were analyzed by SEM–EDS and XRD. The total Cd²⁺ adsorption capacity (Q_c) increased with pyrolysis temperature for both biochars, however, rice straw-derived biochars had greater Q_c than swine manure-derived biochars; hence, the biochar derived from rice straw at 700 °C (RB700) had the largest Q_c, 64.4 mg g⁻¹, of all studied biochars. Cadmium adsorption mechanisms in this study involved precipitation with minerals (Q_cp), cation exchange (Q_ci), complexation with surface functional groups (Q_co), and Cd-π interactions (Q_cπ). Both the pyrolysis temperature and feedstock affected the quantitative contributions of the various adsorption mechanisms. The relative percent contributions to Q_c for Cd²⁺ adsorption by RB and SB were 32.9–72.9% and 35.0–72.5% for Q_cp, 21.7–50.9% and 20.4–43.3% for Q_ci, 2.2–14.8% and 1.4–18.8% for Q_co, and 1.4–3.1% and 3.0–5.8% for Q_cπ, respectively. For biochars produced at higher pyrolysis temperatures, the contributions of Q_cp and Q_cπ to adsorption increased, while the contributions of Q_ci and Q_co decreased. Generally, Q_cp dominated Cd²⁺ adsorption by high-temperature biochars (700 °C) (accounting for approximately 73% of Q_c), and Q_ci was the most prominent mechanism for low-temperature biochars (400 °C) (accounting for 43.3–50.9% of Q_c). Results suggested that biochar derived from rice straw is a promising adsorbent for the Cd²⁺ removal from wastewater and that the low-temperature biochars may outperform the high-temperature biochars for Cd²⁺ immobilization in acidic water or soils.

https://ift.tt/2QFUXo3

Improving the Results of Endonasal Dacryocystorhinostomy with Mitomycin C Application: A Prospective Case–Control Study

Abstract

Many surgical advancement paved to surgical success in endonasal endoscopic dacryocystorhinostomy. Mitomycin C is a systemic chemotherapeutic agent derived from Streptomyces caespitosus that inhibits the synthesis of DNA, cellular RNA, and protein by inhibiting the synthesis of collagen by fibroblasts. The objective of the study was to evaluate the advantage of mitomycin C in primary endoscopic endonasal dacryocystorhinostomy without stenting. Randomised case control design. Tertiary academic centre in central India. 112 patients who presented with epiphora and diagnosed as chronic dacryocystitis after syringing by ophthalmologist, were selected and randomised into two groups with or without mitomycin C intraoperative application. 112 eyes underwent endoscopic-dacryocystorhinostomy. Additional surgeries were done according to necessity. Mitomycin C was applied in concentration of 0.4 mg/dl for 5 min. Patients were followed up on OPD-basis at the end of 1st week, 1st month, 3rd month and over phone call at end of 1 year. Symptomatic improvement assessed by verbal enquiry and clinically by syringing by ophthalmologist. 8 patients underwent septal surgery in case group and 4 in control group along with 1 concha bullosa correction in the case group (p < 0.05). Nil intraoperative complications (p < 0.05) and nil postoperative complication noted (p < 0.05). Functional and anatomical patency found to be 100% at the end of 1st week in both groups, 96.5% at 3rd month in case group and 96.4% and 92.9% at 1 month and 3 month respectively in control group. Nasal endoscopy of all surgical failures showed restenosis in both case group and control group except 1 patient with granulation in control group. Eventhough intraoperative mitomycin C application is effective in increasing the success rate of endonasal DCR surgery in standard nasolacrimal duct obstruction, and with no significant complications from its use, the study did not show added benefit in the primary endoscopic endoscopic dacryocystorhinostomy without stenting.

https://ift.tt/2QGO4Tm

Mitomycin-C in Post-endoscopic Septoplasty Synechiae: Does it Really Helps?

Abstract

Endoscopic septoplasty has advantage of magnified image and access to posterior part of the septum. Synechiae formation is a common complication of this procedure. The incidence of adhesions rises particularly in cases of submucosal flap tears which is sometimes unavoidable during spurectomy. Various procedures like septal splints, nasal packings have been tried to reduce the incidence of adhesions. Recently mitomycin-C is being tried to decrease post operative adhesions after Functional Endoscopic Sinus Surgery, endoscopic Dacrocystorhinostomy, with varying degree of success. Mitomycin-C has got anti fibroblastic activity, which inhibits the fibroblasts without hampering epithelization. Eighty (80) Patients undergoing septoplasty and spurectomy were observed for any submucosal flap tear, and those developing flap tear were included in the study. The patients were divided into 2 groups of 40 each. In group-1 topical mitomycin (0.4 mg/ml) was applied at the raw area for 5 min, similarly normal saline was applied in group-2 (control).The aim of study was to evaluate the role of mitomycin-C in preventing post operative adhesions in Endoscopic septoplasty. Adhesion rate was calculated at 1 month, and compared using Chi square test. P value < 0.05 was considered significant. The adhesion rate at 1 month was 17.5% in group-1 and 45% in group-2 (P = 0.008). Incidence of adhesion decreased significantly in mitomycin-C treated group. Mitomycin-C can routinely be used in septoplasty to prevent post op adhesions, particularly in cases of submucosal flap tears/concurrent turbinate reduction procedures.

https://ift.tt/2xvPdV2

Improving the Results of Endonasal Dacryocystorhinostomy with Mitomycin C Application: A Prospective Case–Control Study

Abstract

Many surgical advancement paved to surgical success in endonasal endoscopic dacryocystorhinostomy. Mitomycin C is a systemic chemotherapeutic agent derived from Streptomyces caespitosus that inhibits the synthesis of DNA, cellular RNA, and protein by inhibiting the synthesis of collagen by fibroblasts. The objective of the study was to evaluate the advantage of mitomycin C in primary endoscopic endonasal dacryocystorhinostomy without stenting. Randomised case control design. Tertiary academic centre in central India. 112 patients who presented with epiphora and diagnosed as chronic dacryocystitis after syringing by ophthalmologist, were selected and randomised into two groups with or without mitomycin C intraoperative application. 112 eyes underwent endoscopic-dacryocystorhinostomy. Additional surgeries were done according to necessity. Mitomycin C was applied in concentration of 0.4 mg/dl for 5 min. Patients were followed up on OPD-basis at the end of 1st week, 1st month, 3rd month and over phone call at end of 1 year. Symptomatic improvement assessed by verbal enquiry and clinically by syringing by ophthalmologist. 8 patients underwent septal surgery in case group and 4 in control group along with 1 concha bullosa correction in the case group (p < 0.05). Nil intraoperative complications (p < 0.05) and nil postoperative complication noted (p < 0.05). Functional and anatomical patency found to be 100% at the end of 1st week in both groups, 96.5% at 3rd month in case group and 96.4% and 92.9% at 1 month and 3 month respectively in control group. Nasal endoscopy of all surgical failures showed restenosis in both case group and control group except 1 patient with granulation in control group. Eventhough intraoperative mitomycin C application is effective in increasing the success rate of endonasal DCR surgery in standard nasolacrimal duct obstruction, and with no significant complications from its use, the study did not show added benefit in the primary endoscopic endoscopic dacryocystorhinostomy without stenting.

https://ift.tt/2QGO4Tm

Mitomycin-C in Post-endoscopic Septoplasty Synechiae: Does it Really Helps?

Abstract

Endoscopic septoplasty has advantage of magnified image and access to posterior part of the septum. Synechiae formation is a common complication of this procedure. The incidence of adhesions rises particularly in cases of submucosal flap tears which is sometimes unavoidable during spurectomy. Various procedures like septal splints, nasal packings have been tried to reduce the incidence of adhesions. Recently mitomycin-C is being tried to decrease post operative adhesions after Functional Endoscopic Sinus Surgery, endoscopic Dacrocystorhinostomy, with varying degree of success. Mitomycin-C has got anti fibroblastic activity, which inhibits the fibroblasts without hampering epithelization. Eighty (80) Patients undergoing septoplasty and spurectomy were observed for any submucosal flap tear, and those developing flap tear were included in the study. The patients were divided into 2 groups of 40 each. In group-1 topical mitomycin (0.4 mg/ml) was applied at the raw area for 5 min, similarly normal saline was applied in group-2 (control).The aim of study was to evaluate the role of mitomycin-C in preventing post operative adhesions in Endoscopic septoplasty. Adhesion rate was calculated at 1 month, and compared using Chi square test. P value < 0.05 was considered significant. The adhesion rate at 1 month was 17.5% in group-1 and 45% in group-2 (P = 0.008). Incidence of adhesion decreased significantly in mitomycin-C treated group. Mitomycin-C can routinely be used in septoplasty to prevent post op adhesions, particularly in cases of submucosal flap tears/concurrent turbinate reduction procedures.

https://ift.tt/2xvPdV2

Survival percentages of atraumatic restorative treatment (ART) restorations and sealants in posterior teeth: an updated systematic review and meta-analysis

Abstract

Objective

The aim of the present study is to update the results of two previous meta-analyses, published in 2006 and 2012, on the survival percentages of atraumatic restorative treatment (ART) restorations and ART sealants. The current meta-analysis includes Chinese publications not investigated before.

Materials and methods

Until February 2017, six databases were interrogated (two English, one Portuguese, one Spanish and two Chinese). Using six exclusion criteria, a group of six independent reviewers selected 43 publications from a total of 1958 potentially relevant studies retrieved. Confidence intervals and/or standard errors were calculated and the heterogeneity variance of the survival rates was estimated.

Results

The survival percentages and standard errors of single-surface and multiple-surface ART restorations in primary posterior teeth over the first 2 years were 94.3% (± 1.5) and 65.4% (± 3.9), respectively; for single-surface ART restorations in permanent posterior teeth over the first 3 years, they were 87.1% (± 3.2); and for multiple-surface ART restorations in permanent posterior teeth over the first 5 years, they were 77% (± 9.0). The mean annual dentine-carious-lesion-failure percentages in previously sealed pits and fissures using ART sealants in permanent posterior teeth over the first 3 and 5 years were 0.9 and 1.9%, respectively.

Conclusions

ART single-surface restorations presented high survival percentages in both primary and permanent posterior teeth, whilst ART multiple-surface restorations presented lower survival percentages. ART sealants presented a high-caries-preventive effect.

Clinical relevance

ART is an effective evidence-based option for treating and preventing carious lesions in primary and permanent posterior teeth.

https://ift.tt/2MMjEf8

Cutaneous angioleiomyoma of the auricle: a painless variant of a painful tumour

Cutaneous angioleiomyomas (ALMs) are uncommon benign tumours of the skin which derive from the smooth muscle layer of dermal blood vessels. They usually present as tender nodules in the fifth or sixth decade of life, predominantly in the legs of females. These tumours rarely present on the head and neck, especially the ear. Head and neck ALMs differ from their more common leg counterparts in that they are painless. Additionally, they do not manifest with a female predominance. Herein, a new case of a painless auricular ALM in a 63-year-old man is reported.

https://ift.tt/2QE1cZD