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With the increase in industrial and agricultural activities, a large amount of nitrogenous compounds are released into the environment, leading to nitrate pollution. The perilous effects of nitrate present in the environment pose a major threat to human and animal health. Bioremediation provides a cost-effective and environmental friendly method to deal with this problem. The process of aerobic denitrification can reduce nitrate compounds to harmless dinitrogen gas. This review provides a brief view of the exhaustive role played by aerobic denitrifiers for tackling nitrate pollution under different ecological niches and their dependency on various environmental parameters. It also provides an understanding of the enzymes involved in aerobic denitrification. The role of aerobic denitrification to solve the issues faced by the conventional method (aerobic nitrification-anaerobic denitrification) in treating nitrogen-polluted wastewaters is elaborated.

The requirement for chemical fertilizers is expected to increase to 200 million tonnes by the year 2022. Increased dependence of farmers on chemical formulations has strengthened agronomic production but has also increased environmental pollution and put the ecosystem stability at higher risk worldwide. Climatic changes have further aggravated the situation by an increase in the frequency of abiotic stresses. However, only 50% of the total habitable land is available for agricultural purposes and there is an urgent need to maintain its fertility and stability. Therefore, improved crop productivity and enhanced food security with a reduced or negligible application of chemical fertilizers and pesticides have become a major test these days. Plant growth-promoting rhizobacteria (PGPR) are at the forefront of sustainable agricultural practices. They are a secure and favorable alternative to chemical fertilizers as well as a useful option to decrease stress conditions. Many bacterial species act as PGPRs and have visibly improved plant growth, health, and productivity. This review emphasizes the role of PGPRs in sustainable agriculture, underlying mechanisms involved in growth promotion, and the exploitation of these rhizobacteria under different stress conditions.

Rhizosphere supports the growth and activity of an enormous and diversified microbial network. Certain rhizobacteria referred to as ‘plant growth-promoting rhizobacteria’ (PGPR) can contribute towards improved plant growth and stress tolerance and are currently of great interest for sustainable agriculture. A successful PGPR is capable of establishing itself in the rhizosphere of inoculated plants. Root colonization is an essential step in the interaction amongst plant-associated bacteria and host plant and is a multifaceted phenomenon governed by various biotic and abiotic factors. In the present investigation, an isolate MT7 obtained from maize rhizosphere and identified as Bacillus sp. was tested for its ability to perform in the tomato rhizosphere. It was screened for its survival under various abiotic stresses like salt, drought, heavy metals, and temperature and found to tolerate 10% salt stress, drought stress up to -0.73 MPa (25% PEG), heavy metals like Cr, Cu, and Ni above the permissible limits and grew well from 25 to 45 °C. The bacterial culture was verified for various other plant growth-promoting traits. It expressed chemotactic behavior and good biofilm-forming potential in the presence of tomato root exudates. Profuse colonization was observed on the tomato roots. Efficacy of the bacterial culture in the tomato rhizosphere was evaluated under net house conditions. The tomato crop was positively influenced by inoculation of MT7 over the un-inoculated plants. Therefore, it is concluded that competent colonization by MT7 lies in its ability to respond to tomato root exudates, form biofilms, establish and proliferate in the tomato rhizosphere and express various PGP traits that cause an increase in plant growth. The results indicate the potential of MT7 as a bio-inoculant for tomato.

Placement of an indwelling pleural catheter is an established modality for symptom relief and pleurodesis in the treatment of malignant pleural effusion. Concerns remain regarding possible infectious complications, risk of hemorrhage, and the rate of pleurodesis with the use of pleural catheters in the treatment of hematologic malignancies.The goals of our study were: (1) to evaluate the safety and cumulative incidence of pleurodesis with indwelling pleural catheters for patients with hematologic malignancies, and (2) to evaluate overall survival of this cohort of patients with pleural effusions.We performed a retrospective review of 172 patients with a hematologic malignancy who underwent placement of an indwelling pleural catheter between September 1997 and August 2011 at the University of Texas MD Anderson Cancer Center in Houston, Texas. A competing risk model analysis was used for complications and pleurodesis. Analysis was based on each patient's first intrapleural catheter.There were 172 patients with lymphoma (58%), acute (16%) or chronic leukemia (16%), or multiple myeloma (10%). The effusions were characterized as malignant (85.5%), infectious (4.1%), volume overload (4.7%), or therapy-related (4.7%). Chylothorax was found in 20.1%. Pleural biopsies were obtained from 13 patients. The cumulative incidence of all complications was 13.6%, and the cumulative incidence of all significant catheter-related complications was 9.5%. The incidence of empyema was 2.9%, and major bleeding (requiring transfusion or intervention) was 1.7%. Thirty-day procedure-associated mortality was 0.6%. The cumulative incidence of pleurodesis at 180 days was 50%, with a median time to pleurodesis of 81 days for the entire cohort.Indwelling pleural catheters appear to be safe for patients with hematologic malignancies. Complications and the cumulative incidence of pleurodesis are comparable to those reported for patients with solid organ malignancies.

Descrevemos o caso de um homem de 33 anos de idade, usuário crônico de cocaína em pó, que apresentava dispneia, febre, sudorese noturna e perda de peso significativa. A TCAR de tórax revelou nódulos centrolobulares, dando uma impressão inicial de tuberculose miliar. Por isso, o paciente passou a receber tratamento empírico com quatro tuberculostáticos. Quatro semanas depois, apesar do tratamento antituberculose, o paciente continuou a apresentar os mesmos sintomas. Foi então realizada a biópsia pulmonar transbrônquica. A análise histopatológica da amostra obtida revelou granuloma de corpo estranho birrefringente. A história de uso de cocaína por inalação, a presença de nódulos centrolobulares e os achados histopatológicos de corpos estranhos confirmaram o diagnóstico de granulomatose pulmonar de corpo estranho. Este relato destaca o fato de que a granulomatose pulmonar de corpo estranho deve ser incluída no diagnóstico diferencial de perfis clínicos que se assemelham a tuberculose. We describe the case of a 33-year-old man, a chronic user of powder cocaine, who presented with dyspnea, fever, night sweats, and significant weight loss. Chest HRCT revealed centrilobular nodules, giving an initial impression of miliary tuberculosis. Therefore, he was started on an empirical, four-drug antituberculosis treatment regimen. Four weeks later, despite the tuberculosis treatment, he continued to have the same symptoms. We then performed transbronchial lung biopsy. Histopathological analysis of the biopsy sample revealed birefringent foreign body granuloma. A corroborative history of cocaine snorting, the presence of centrilobular nodules, and the foreign body-related histopathological findings led to a diagnosis of pulmonary foreign body granulomatosis. This report underscores the fact that pulmonary foreign body granulomatosis should be included in the differential diagnosis of clinical profiles resembling tuberculosis. Univ Fed Sao Paulo, Escola Paulista Med, Hosp Sao Paulo, Disciplina Cirurgia Torac,Dept Cirurgia, Sao Paulo, SP, Brazil Fundacao ABC, Fac Med, Disciplina Cirurgia Torac, Santo Andre, SP, Brazil SurgP&D Consultoria, Pesquisa & Desenvolvimento Cirurgia, Sao Paulo, SP, Brazil Univ Fed Sao Paulo, Escola Paulista Med, Sao Paulo, SP, Brazil Disciplina de Cirurgia Torácica, Departamento de Cirurgia, Hospital São Paulo, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo (SP) Brasil Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo (SP) Brasil Web of Science