Removal of cadmium and arsenic from water through biomineralization.

Due to anthropogenic activities, heavy metals such as cadmium (Cd) and arsenic (As) are one of the most toxic xenobiotics contaminating water, thus affecting human health and the environment. The objective of the present investigation was to study the effect of ureolytic bacteria Bacillus paramycoides-MSR1 for the bioremediation of Cd and As from contaminated water. The B. paramycoides showed high resistance to heavy metals, Cd and As, with minimum inhibitory concentration (MIC) of 12.84 µM and 48.54 µM, respectively. The urease activity and calcium carbonate (CaCO3) precipitation were evaluated in artificial wastewater with different concentrations of Cd (0, 10, 20, 30, 40, 50, and 60 µM) and As (0, 20, 40, 60, 80, and 100 µM). The maximum urease activity in Cd-contaminated artificial wastewater was observed after 96 hours, which showed a 76.1% decline in urease activity as the metal concentration increased from 0 to 60 µM. Similarly, 14.1% decline in urease activity was observed as the concentration of As was increased from 0 to 100 µM. The calcium carbonate precipitation at the minimum inhibitory concentration of Cd and As-contaminated artificial wastewater was 189 and 183 mg/100 ml, respectively. The percentage removal of metal from artificially contaminated wastewater with varied concentrations was analyzed using atomic absorption spectroscopy (AAS). After 168 hours of incubation, 93.13% removal of Cd and 94.25% removal of As were observed. Microstructural analysis proved the presence of calcium carbonate in the form of calcite, confirming removal of cadmium and arsenic by microbially induced calcium carbonate precipitation (MICCP) to be promising technique for water decontamination.

Autologous fat transfer for orbital volume augmentation in sockets with small nonseeing eyes.

OBJECTIVE: End-stage ocular diseases usually end up with atrophic bulbi or phthisis bulbi leading to orbital volume loss which needs to be addressed. We studied the use of autologous fat for volume augmentation of the orbit because it is minimally invasive and allows early rehabilitation with the use of an artificial eye. DESIGN: It was a prospective, interventional study. METHODS: A total of 14 eyes of 14 patients with atrophic bulbi with shrinkage or phthisis bulbi with no perception of light (PL) and aged older than 18 years were included for the study purpose. Painful or inflamed eyes or suspected intraocular tumors were excluded. An autologous fat graft was obtained from the lower abdomen or buttocks and injected into the retrobulbar space using a 20-gauge cannula after adequate peribulbar anesthesia. Outcomes measures were patient satisfaction, change in Hertel's exophthalmometry, vertical and horizontal palpebral aperture, and socket volume. RESULTS: Hertel exophthalmometry showed a significant improvement both with and without an artificial eye from 14.92 ± 2.3 mm to 16.71 ± 1.94 mm (p-value 0.003 without an artificial eye). The vertical palpebral aperture also showed a significant improvement from 5 ± 1.70 mm to 6.71 ± 1.58 mm (p-value < 0.001). There was a significant reduction in the socket volume from 1.22 ml to 0.39 ml (p-value < 0.001). No local or donor site complications were seen. CONCLUSIONS: Autologous fat transfer is a minimally invasive, safe, and effective procedure for orbital volume augmentation in small, nonseeing eyes. The short-term outcome of our study was good in most patients and can be considered for such patients.

Bilateral Immune-Mediated Keratolysis After Immunization With SARS-CoV-2 Recombinant Viral Vector Vaccine.

PURPOSE: The purpose of this study was to report an unusual case of bilateral immune-mediated corneal melting and necrosis after ChAdOx1 nCoV-19 (Covishield) vaccination. METHODS: This is a case report and literature review. RESULTS: A 48-year-old man presented to the ophthalmic emergency department with progressive bilateral corneal melting 5 weeks after receiving the first dose of ChAdOx1 nCoV-19 (Covishield) vaccine. Systemic complaints of fever, diarrhea, and vomiting were noted in the first 2 weeks, which subsided before the onset of ocular symptoms at day 21 of vaccine administration. The patient could only perceive light bilaterally and demonstrated features of bilateral keratolysis with choroidal detachment on ultrasonography. The microbiological scraping specimen did not reveal growth of any microorganism. Tectonic penetrating keratoplasty was performed, and the host corneal tissue was sent for histopathology, bacterial culture, fungal culture, polymerase chain reaction for herpes simplex virus, varicella zoster virus, cytomegalovirus, adenovirus, and SARS-CoV-2. Microbial culture was sterile, and viral polymerase chain reaction reports were negative. Histopathological examination revealed dense inflammatory cell infiltration. Detailed systemic workup revealed no underlying systemic or autoimmune pathology. CONCLUSIONS: Immune-mediated keratolysis after ChAdOx1 nCoV-19 (Covishield) vaccination is a rare entity, and we believe that this is the first report of a temporal association between a serious ocular adverse event after a single dose of any SARS-CoV-19 vaccine. It may be included as a possible adverse event associated with this vaccine.

Optimal refinement of residents' surgical skills by training on induced goat's eye corneoscleral perforation.

Surgical skill enhancement for the residents under training can be performed through various efforts. Here in this report, the authors describe a technique of corneoscleral perforation repair on goat's eye, as the tissue resemblance and the reality of experience while performing crucial steps are similar to human eyes. Beginning from tissue handling, optimal suture placement was taught with an intention to impart quality techniques of traumatic globe injury repair. Therefore, rather than training on expensive artificial eye model, training budding surgeons on goat's eye gives much more realistic tissue handling experiences in the presence of constant challenges almost similar to human eyes.

A crosslinked and ribosylated actin trimer does not interact productively with myosin.

A purified F-actin-derived actin trimer that interacts with end-binding proteins did not activate or bind the side-binding protein myosin under rigor conditions. Remodeling of the actin trimer by the binding of gelsolin did not rescue myosin binding, nor did the use of different means of inhibiting the polymerization of the trimer. Our results demonstrate that ADP-ribosylation on all actin subunits of an F-actin-derived trimer inhibits myosin binding and that the binding of DNase-I to the pointed end subunits of a crosslinked trimer also remodels the myosin binding site. Taken together, this work highlights the need for a careful balance between modification of actin subunits and maintaining protein-protein interactions to produce a physiologically relevant short F-actin complex.

Iron-based superparamagnetic nanoparticle contrast agents for MRI of infection and inflammation.

OBJECTIVE. In this article, we summarize the progress to date on the use of superparamagnetic iron oxide nanoparticles (SPIONs) as contrast agents for MRI of inflammatory processes. CONCLUSION. Phagocytosis by macrophages of injected SPIONs results in a prolonged shortening of both T2 and T2* leading to hypointensity of macrophage-infiltrated tissues in contrast-enhanced MR images. SPIONs as contrast agents are therefore useful for the in vivo MRI detection of macrophage infiltration, and there is substantial research and clinical interest in the use of SPION-based contrast agents for MRI of infection and inflammation. This technique has been used to identify active infection in patients with septic arthritis and osteomyelitis; importantly, the MRI signal intensity of the tissue has been found to return to its unenhanced value on successful treatment of the infection. In SPION contrast-enhanced MRI of vascular inflammation, animal studies have shown decreased macrophage uptake in atherosclerotic plaques after treatment with statin drugs. Human studies have shown that both coronary and carotid plaques that take up SPIONs are more prone to rupture and that abdominal aneurysms with increased SPION uptake are more likely to grow. Studies of patients with multiple sclerosis suggest that MRI using SPIONs may have increased sensitivity over gadolinium for plaque detection. Finally, SPIONs have enabled the tracking and imaging of transplanted stem cells in a recipient host.