Co oxide nanostructures for electrocatalytic water-oxidation: effects of dimensionality and related properties

A facile hydrothermal synthesis route was explored to obtain various nanostructures of Co oxide for applications in electrocatalytic water-splitting. The effect of reaction time and metal precursor ions on the morphology of synthesized nanostructures was studied in detail with the aid of a scanning electron microscope. By systematic optimization of the synthesis parameters, Co oxide nanostructures with single dimensionality were obtained in the form of 0D nanoparticles (NPs), 1D nanowires (NWs), 2D nanosheets (NSs) and 3D nanocrystals (NCs). The effectiveness of the developed nanostructures towards oxygen evolution reaction (OER) was studied and a promising OER activity was recorded for all the samples. Amongst all the developed catalysts, Co(OH)2 NPs showed the lowest overpotential of 339 mV to achieve a current density of 10 mA cm-2, which is even lower than that of noble-metal oxides such as the commercial RuO2 catalyst (370 mV). The specific effect of different parameters such as BET surface area, phase, crystallographic orientation of surface lattice planes, electroactive surface area and surface active species on the OER performance was studied. It was found that the Co3O4 phase is more active for the OER, compared to the Co(OH)2 phase. However, Co(OH)2 NPs showed the best OER performance owing to their higher BET surface area, thereby underlining the significance of the catalyst surface area. The effect of the number of active surface atoms was demonstrated by estimating the electroactive surface area of all Co3O4 nanostructures. It was also shown that the formation of CoO2 species (Co(IV)) on the surface is more beneficial for the OER as compared to the formation of CoOOH species (Co(III)). Finally, the robustness of the developed Co3O4 nanostructures was established by performing a recycling test for the OER (1000 cycles) and the observed change in the catalytic activity was correlated with morphological variation.

Ascertaining the regenerative potential of the "gold standard" grafts: Achieving 100% root coverage in Miller's Class III recession with periosteal pedicle graft and autogenous bone

Recession of the gingiva is defined as the stripping of a portion of the dental root surface as a result of gingival margin shifting apically. Various techniques have been advocated for root coverage. The practice of utilizing periosteal pedicle graft for covering gingival recession defects is a contemporary development. Utilizing bone grafts for hard tissue regeneration has also been implemented. This case report assesses the effectiveness of the surgical approach utilizing autogenous bone and periosteum for recession coverage. A participant with Miller's Class III gingival recession in #23 and #24 was treated using this technique. The loss of periodontal attachment was recorded to be 8 mm and 5 mm on the mid-buccal surface of the upper left canine and first premolar, respectively. Clinical parameters were recorded at 1, 3, 6, 9, and 12 months postoperatively. Complete root coverage was achieved when evaluated from baseline till 12 months, with clinical attachment level and keratinized tissue gain. The results of esthetics in terms of color match and tissue contours were satisfactory to the patient as well as to the clinicians.

Pattern of mismatch repair protein loss and its clinicopathological correlation in colorectal cancer in North India

BACKGROUND

To determine the mismatch repair (MMR) protein loss in colorectal cancer (CRC) in north Indian patients and its clinicopathological correlation.

METHOD

A prospective study on patients with colorectal cancer from a tertiary level hospital conducted between May 2014 and June 2015. MMR protein loss was determined using immunohistochemistry for MLH1, MSH2, PMS2 and MSH6.

RESULTS

52 patients (38 male and 14 females) of CRC, with median age of 52.5 years who underwent resection form the study group. 18 (35%) patients were < 50 years of age. Family history of malignancy was present in 3 (6 %) patients. A total of 15 (29%) patients had loss of MMR protein of which 7 (46%) were < 50 years. Most common MMR loss was combined loss of MSH2 + MSH6 [6 (11.5%)] followed by isolated loss of PMS2 [5 (9.6%)]. MMR protein loss was more frequent in patients with right side colon cancer [12 (42%)] compared to left [3 (13%)] (p = 0.033). MMR protein loss was seen in 11 (34%) out of 32 patients fulfilling the revised Bethesda criteria compared to 4 (20%) out of 20 patients who did not fulfil the criteria (p = 0.352).

CONCLUSION

This study demonstrates high frequency of MMR protein loss in colorectal cancer in north Indian patients which was more common in right colon cancer. Many patients having MMR protein loss do not satisfy the revised Bethesda criteria and would have been missed if selective testing was done. Further research and larger studies are required to validate these findings and develop India specific clinical criteria.

Abstract P5-03-10: IL-6 and CCL5 secretion by adipose-derived stem cells and the breast tumor microenvironment

Introduction: Obesity is a key factor in promoting aggressive breast cancers in women. In previous studies, we found increased production of IL-6 and CCL5, common pro-inflammatory cytokines, in co-cultures of adipose stem cells and triple negative breast tumor cells. When we probed The Cancer Genome Atlas (TCGA) for triple negative breast cancer, we discovered that CCL5 overexpression was associated with improved survival. This finding contradicts the majority of in vitro studies regarding the role of CCL5 in the breast tumor microenvironment; the literature suggests that CCL5 promotes tumor metastatic ability. Furthermore, TCGA data did not indicate a significant correlation between IL-6 production and survival outcomes. It remains unclear whether CCL5 and IL-6 are produced by adipose stromal cells or cancer cells within the tumor microenvironment. We predict that the primary source of CCL5 and IL-6 is from adipose stromal cells. However, the production of these cytokines may be altered when exposed to tumor-secreted factors. Methods: Adipose-derived stem cells (ASC) and preadipocytes differentiated from ASCs (Pread(A)) were treated with the conditioned media of triple negative breast tumor cells (MDA-MB-231) and luminal A breast tumor cells (MCF-7). In addition, MDA-MB-231 and MCF-7 cells were treated with the conditioned media of each adipose stromal cell type. After 72 hours of treatment, the media harvested from each cell type was analyzed for secreted IL-6 and CCL5 proteins. Results: IL-6 and CCL5 levels in the conditioned media of ASCs treated with MDA-MB-231 or MCF-7 cells were significantly lower (p&lt;0.05) when compared to the media of ASCs alone. The reverse occurred when tumor cells were provided conditioned media from adipose progenitor cells. When both breast tumor cell lines were exposed to conditioned media from ASCs and Pread(A), the secretion of IL-6 and CCL5 increased significantly (p&lt;0.05). The conditioned media of Pread(A) cells treated with breast tumor cells were lower than untreated cells, however, this decrease in cytokine production was not significant. Conclusions: This study suggests that IL-6 and CCL5 secretion by adipocytes is modified by the presence of breast tumor cells. The significant decrease in IL-6 and CCL5 secretion from both adipose-derived stem cells and preadipocytes in the presence of tumor may suggest an attempt by the tumor to inhibit an inflammatory response by adipose stromal cells while increasing its own IL-6 and CCL5 production. Although the human genome data indicates that CCL5 and IL-6 provide a survival benefit in vivo, laboratory in vitro studies thus far have failed to mimic the observed clinical responses. Further studies will investigate the clinical relevance of CCL5 and IL-6 receptors in breast cancer. (Supported by NIH P20GM103434 and NIGMS U54GM104942)

Citation Format: Vona-Davis L, Lundstrom E, Berrebi D, Werwie N, Yadav A. IL-6 and CCL5 secretion by adipose-derived stem cells and the breast tumor microenvironment [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P5-03-10.

Structural basis for substrate discrimination byE. colirepair enzyme, AlkB

Positive charge on methylated nucleotides is a prime criterion for substrate recognition byE. coliAlkB.

Role of angiotensin converting enzyme and angiotensinogen gene polymorphisms in angiotensin converting enzyme inhibitor-mediated antiproteinuric action in type 2 diabetic nephropathy patients

AIM

To investigate the role of genetic variants of angiotensin converting enzyme (ACE) and angiotensinogen (AGT) genes in the antiproteinuric efficacy of ACE inhibitor therapy in diabetic nephropathy (DN) patients.

METHODS

In the present study, 270 type 2 diabetes mellitus patients with nephropathy were enrolled and treated with ACE inhibitor (ramipril) and followed at 6 mo for renal function and albumin excretion by estimating serum creatinine, end stage renal disease, and albumin/creatinine ratio (ACR) in urine. Genotyping of ACE I/D and AGT M235T polymorphisms were performed by using primer specific polymerase chain reaction (PCR) and PCR-RFLP techniques, respectively.

RESULTS

Forty-eight percent of DN patients (responders) benefited with respect to proteinuria from ACE inhibitor therapy at 6 mo follow-up. A significant reduction in ACR was observed after 6 mo treatment with ACE inhibitor irrespective of whether DN patients were micro-albuminuric (≥ 30 and < 300 mg/g creatinine) or macro-albuminuric (≥ 300 mg/g creatinine) at the time of enrollment. However, macro-albuminuric patients (55%) showed better response to therapy. A reduction in urinary ACR was found independent of genotypes of ACE I/D and AGT M235T polymorphisms although macro-albuminuric patients having TT genotype showed statistically insignificant increased response (72%).

CONCLUSION

ACE inhibitor therapy reduced urinary ACR by ≥ 30% in 50% of DN patients and the response is independent of ACE I/D and AGT M235T polymorphisms.

Detection of amitraz and malathion resistance in field populations of Rhipicephalus (Boophilus) microplus (Acari: Ixodidae) in Jammu region of India

Detection of resistance levels against amitraz and malathion in Rhipicephalus (Boophilus) microplus collected from four districts of Jammu region (India) was carried out using the adult immersion test. The regression graphs of probit mortality of ticks plotted against log values of concentration of drugs were utilised for the determination of slope of mortality, lethal concentration for 50% (LC₅₀), 95% (LC₉₅) and resistance factor (RF). On the basis of the data generated on variables (mortality, egg mass weight, reproductive index and percentage inhibition of oviposition) the resistance level was categorised as I, II, III and IV. Out of these four districts, resistance to amitraz was detected at level I in Udhampur (RF = 2.81), Jammu (RF = 2.53) and Samba isolates (RF = 2.24) whereas Rajouri isolate was found susceptible (RF = 1.0). Resistance to malathion was detected at level I in Udhampur (RF = 4.01) and Jammu isolates (RF = 1.76) whereas Rajouri (RF = 0.472) and Samba (RF = 0.199) isolates were found susceptible. The data generated on amitraz and malathion resistance status will help in formulating a tick control strategy in the region.

Pt–CeO2 nanoporous spheres – an excellent catalyst for partial oxidation of methane: effect of the bimodal pore structure

Bimodal pore size distribution played the most important role for the catalyst's superior activity during POM.

NEED OF IRON SUPPLEMENTATION IN GESTATIONAL DIABETES MELLITUS

Objective

Gestational diabetes mellitus (GDM) increases the foetal morbidity and mortality and there is also risk of development of type II diabetes for the mother. In pregnancy iron supplementations are given to all the females in India. Data are not available on the relationship between serum ferritin and GDM in Indian populations.

Material & Methods

Case control study was done on 90 women (30 GDM patients approx 28 weeks of gestation and 60 control subjects without GDM) referred to the tertiary care hospital at New Delhi. Ferritin was analysed by ELISA kit. They were analyzed for the correlation of ferritin with blood glucose in GDM patients.

Results

On comparison with blood glucose the levels of ferritin were statistically significantly high in GDM cases as compared to controls (p value 0.008). There was a negative correlation of ferritin with blood glucose level (r value -0.039, p value 0.794).

Discussion

Pregnancy is an equivalent of an inflammatory state and the high levels of ferritin can help in determining the need of iron supplementation given in pregnant females. Women who had high serum ferritin had the greatest risk of GDM.

Conclusion

This study suggests a possible link between elevated serum ferritin and low-grade inflammation. Further studies in larger populations are required to establish this study.

Acute thyroid swelling in renal transplant recipient

Tuberculosis (TB) of thyroid gland is rare entity even in solid organ transplant recipients who have a high risk of TB. Thyroid TB is easily diagnosed by fine needle aspiration cytology. The majority of cases require only antitubercular drugs for treatment, and surgical intervention is required only in few patients. We here describe a case of thyroid TB presenting as an acute abscess in postrenal transplant recipient with a background of acute rejection treated with steroid and antithymocyte globulin.

Microbial profile of the vitreous aspirates in culture proven exogenous endophthalmitis: A 10-year retrospective study

PURPOSE

To describe the microbiological profile and clinical outcome in the eyes with culture-proven exogenous endophthalmitis.

METHODS

A retrospective analysis of 495 eyes diagnosed as exogenous endophthalmitis was performed over a period of 10 years. In all, aseptically collected aqueous and vitreous aspirates were cultured for bacteria and fungus using standard microbiological techniques. Gram-stain and KOH preparation of the specimens were also performed. The antibiotic susceptibility testing for bacterial isolates was performed by Kirby-Bauer disk diffusion method. The treatment was modified according to the antibiotic sensitivity profile. The final clinical ocular condition was divided into improved, stable or deteriorated.

RESULTS

Of 148 culture-proven endophthalmitis eyes, 137 (92.57%) were referred from elsewhere, and 11 (7.43%) belonged to our institute. Aetiologically, 76 (51.35%) eyes were post-cataract surgery, 61 (41.22%) were post-traumatic, 5 (3.38%) eyes post-intravitreal anti-vascular endothelial growth factor injection, 5 associated with corneal diseases and 1 bleb-related endophthalmitis. In 31 (20.95%) eyes, primary intravitreal antibiotics were given outside. The cultures revealed monomicrobial growth in 92.57% (n = 137) and polymicrobial growth in 7.43% (n = 11). Among the bacteria (n = 121, 81.76%), Pseudomonas species dominated overall (n = 32, 27.11%) and post-operative (n = 26, 38.23%) endophthalmitis group. Staphylococcus epidermidis (n = 14, 28%) was prominent in post-traumatic endophthalmitis group. Ninety-two percent (n = 108 isolates) of bacteria were sensitive to vancomycin. In 78 (52.7%) eyes, the clinical ocular condition improved or remained stable while deteriorated in 51 (34.46%).

CONCLUSION

A bacterial predominance was observed among causative organisms of exogenous endophthalmitis with Pseudomonas species being the most common. The appropriate surgical intervention improved or stabilised the visual acuity in nearly 50% eyes.

PSINET: Assisting HIV Prevention Amongst Homeless Youth by Planning Ahead

Homeless youth are prone to Human Immunodeficiency Virus (HIV) due to their engagement in high risk behavior such as unprotected sex, sex under influence of drugs, etc. Many non-profit agencies conduct interventions to educate and train a select group of homeless youth about HIV prevention and treatment practices and rely on word-of-mouth spread of information through their social network. Previous work in strategic selection of intervention participants does not handle uncertainties in the social network's structure and evolving network state, potentially causing significant shortcomings in spread of information. Thus, we developed PSINET, a decision support system to aid the agencies in this task. PSINET includes the following key novelties: (i) it handles uncertainties in network structure and evolving network state; (ii) it addresses these uncertainties by using POMDPs in influence maximization; and (iii) it provides algorithmic advances to allow high quality approximate solutions for such POMDPs. Simulations show that PSINET achieves ~60% more information spread over the current state-of-the-art. PSINET was developed in collaboration with My Friend's Place (a drop-in agency serving homeless youth in Los Angeles) and is currently being reviewed by their officials.