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1.
Front Microbiol ; 13: 1063594, 2022.
Article in English | MEDLINE | ID: mdl-36523823

ABSTRACT

Pit lakes are one of the greatest legacies of open-cut mining. Despite the potential hazards of these lakes, they represent newly formed ecosystems with great scientific and ecological potential. Although thousands of pit lakes occur on every inhabited continent, with more being created, the microbial ecology of pit lakes is relatively under-researched. We evaluated the current state of microbial research in pit lakes by performing a Web of Science search and creating a literature database. Study lakes were categorized according to location and water quality (pH and conductivity) which is a key community and environmental concern. Research technology employed in the study was also categorized. We compared research effort in lakes, rivers, and streams which are the more "charismatic" inland aquatic ecosystems. Pit lake publications on microbes from 1987 to 2022 (n = 128) were underrepresented in the literature relative to rivers and streams (n = 321) and natural lakes (n = 948). Of the 128 pit lake publications, 28 were within the field of geochemistry using indirect measures of microbial activity. Most pit lake microbial research was conducted in a few acidic lakes in Germany due to social pressure for remediation and government initiative. Relatively few studies have capitalized on emerging technology. Pit lake microbial research likely lags other more charismatic ecosystems given that they are viewed as performing "ecosystem disservices," but this is socially complex and requires further research. Improving understanding of microbial dynamics in pit lakes will allow scientists to deliver safer pit lakes to communities.

2.
Microorganisms ; 9(6)2021 Jun 03.
Article in English | MEDLINE | ID: mdl-34204924

ABSTRACT

Mine pit lakes ('pit lakes') are new aquatic ecosystems of the Anthropocene. Potentially hundreds of meters deep, these lakes are prominent in the landscape and in the public consciousness. However, the ecology of pit lakes is underrepresented in the literature. The broad goal of this research was to determine the environmental drivers of pelagic microbe assemblages in Australian coal pit lakes. The overall experimental design was four lakes sampled three times, top and bottom, in 2019. Instrument chains were installed in lakes and measurements of in situ water quality and water samples for metals, metalloids, nutrients and microbe assemblage were collected. Lakes were monomictic and the timing of mixing was influenced by high rainfall events. Water quality and microbial assemblages varied significantly across space and time, and most taxa were rare. Lakes were moderately saline and circumneutral; Archeans were not prevalent. Richness also varied by catchment. Microbial assemblages correlated to environmental variables, and no one variable was consistently significant, spatially or temporally. Study lakes were dominated by 'core' taxa exhibiting temporal turnover likely driven by geography, water quality and interspecific competition, and the presence of water chemistry associated with an artificial aquifer likely influenced microbial community composition. Pit lakes are deceptively complex aquatic ecosystems that host equally complex pelagic microbial communities. This research established links between microbial assemblages and environmental variables in pit lakes and determined core communities; the first steps towards developing a monitoring program using microbes.

3.
J Am Mosq Control Assoc ; 32(3): 203-209, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27802404

ABSTRACT

Floating emergence traps were used in 15 road gullies to determine the effectiveness and longevity of S-methoprene briquets over 124 days. Samples were taken monthly from October 2014 to March 2015. Two treatment methods were assessed: application of briquet using a float, and application without a float. These methods were compared with untreated control gullies. Mosquito emergence peaked in early November, and decreased by February. Effectiveness of the briquet was not impacted significantly by the presence or absence of a float (P = 0.329). Gullies yielded a mean of 108 mosquitoes per day per gully over the season. Culex quinquefasciatus and Aedes notoscriptus were the most abundant species. The maximum number of Cx. quinquefasciatus emerging could exceed 1,600 per day per gully. Aedes notoscriptus numbers could exceed 70 adults per day per gully. Treatment with S-methoprene was highly effective against both species for at least 70 days and partially effective for up to 120 days. Treatment provided no control by day 124. S-methoprene provided 90% control over 124 days. Road gullies have been confirmed as a significant larval habitat and are likely to be increasing the potential for Ross River virus transmission in the area.


Subject(s)
Alphavirus Infections/prevention & control , Culicidae , Juvenile Hormones , Methoprene , Mosquito Control , Aedes , Alphavirus Infections/transmission , Animals , Cities , Culex , Female , Male , Mosquito Control/methods , Ross River virus/physiology , Western Australia
4.
Environ Sci Pollut Res Int ; 23(6): 5915-24, 2016 03.
Article in English | MEDLINE | ID: mdl-26593729

ABSTRACT

Open-cut mining operations can form pit lakes on mine closure. These new water bodies typically have low nutrient concentrations and may have acidic and metal-contaminated waters from acid mine drainage (AMD) causing low algal biomass and algal biodiversity. A preliminary study was carried out on an acidic coal pit lake, Lake Kepwari, in Western Australia to determine which factors limited algal biomass. Water quality was monitored to obtain baseline data. pH ranged between 3.7 and 4.1, and solute concentrations were slightly elevated to levels of brackish water. Concentrations of N were highly relative to natural lakes, although concentrations of FRP (<0.01 mg/L) and C (total C 0.7-3.7 and DOC 0.7-3.5 mg/L) were very low, and as a result, algal growth was also extremely low. Microcosm experiment was conducted to test the hypothesis that nutrient enrichment will be able to stimulate algal growth regardless of water quality. Microcosms of Lake Kepwari water were amended with N, P and C nutrients with and without sediment. Nutrient amendments under microcosm conditions could not show any significant phytoplankton growth but was able to promote benthic algal growth. P amendments without sediment showed a statistically higher mean algal biomass concentration than controls or microcosms amended with phosphorus but with sediment did. Results indicated that algal biomass in acidic pit lake (Lake Kepwari) may be limited primarily by low nutrient concentrations (especially phosphorus) and not by low pH or elevated metal concentrations. Furthermore, sediment processes may also reduce the nutrient availability.


Subject(s)
Chlorophyta/growth & development , Lakes , Mining , Australia , Biodiversity , Biomass , Hydrogen-Ion Concentration , Phosphorus/analysis , Phytoplankton/growth & development , Plants , Water Pollution , Water Quality , Western Australia
5.
J Bronchology Interv Pulmonol ; 20(3): 266-70, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23857204

ABSTRACT

Recurrent pneumonias often occur in the setting of an airway obstruction and can be the presenting symptom of an undiagnosed malignancy. Little is known regarding the microbiology of these pneumonias making antibiotic therapy difficult to direct; however, the few studies available show these pneumonias to be polymicrobial. Examining the colonization patterns of at-risk populations such as patients with chronic obstructive pulmonary disease and using techniques such as ultrasound and computed tomography-guided biopsies may help in the treatment of these pneumonias. The following review is presented to highlight the current medical knowledge as well as suggest areas for future evaluation.


Subject(s)
Lung Neoplasms/complications , Pneumonia/microbiology , Pulmonary Disease, Chronic Obstructive/complications , Bronchoscopy , Gram-Positive Bacterial Infections/complications , Gram-Positive Bacterial Infections/drug therapy , Humans , Pneumonia/diagnosis , Pneumonia/etiology
6.
J Environ Manage ; 92(10): 2419-26, 2011 10.
Article in English | MEDLINE | ID: mdl-21616580

ABSTRACT

Pit lakes (abandoned flooded mine pits) represent a potentially valuable water resource in hot arid regions. However, pit lake water is often characterised by low pH with high dissolved metal concentrations resulting from Acidic and Metalliferous Drainage (AMD). Addition of organic matter to pit lakes to enhance microbial sulphate reduction is a potential cost effective remediation strategy. However, cost and availability of suitable organic substrates are often limiting. Nevertheless, large quantities of sewage and green waste (organic garden waste) are often available at mine sites from nearby service towns. We treated AMD pit lake water (pH 2.4) from tropical, North Queensland, Australia, with primary-treated sewage sludge, green waste, and a mixture of sewage and green waste (1:1) in a controlled microcosm experiment (4.5 L). Treatments were assessed at two different rates of organic loading of 16:1 and 32:1 pit water:organic matter by mass. Combined green waste and sewage treatment was the optimal treatment with water pH increased to 5.5 in only 145 days with decreases of dissolved metal concentrations. Results indicated that green waste was a key component in the pH increase and concomitant heavy metal removal. Water quality remediation was primarily due to microbially-mediated sulphate reduction. The net result of this process was removal of sulphate and metal solutes to sediment mainly as monosulfides. During the treatment process NH(3) and H(2)S gases were produced, albeit at below concentrations of concern. Total coliforms were abundant in all green waste-treatments, however, faecal coliforms were absent from all treatments. This study demonstrates addition of low-grade organic materials has promise for bioremediation of acidic waters and warrants further experimental investigation into feasibility at higher scales of application such as pit lakes.


Subject(s)
Biodegradation, Environmental , Carbon/chemistry , Conservation of Natural Resources/methods , Metals, Heavy , Plants/chemistry , Sewage/chemistry , Sulfates/metabolism , Acids , Ammonia/metabolism , Australia , Enterobacteriaceae/metabolism , Gardening , Humans , Hydrogen Sulfide/metabolism , Hydrogen-Ion Concentration , Lakes , Mining , Plants/microbiology , Sewage/microbiology , Water Microbiology , Water Pollutants , Water Purification/methods , Water Quality
7.
Chest ; 138(3): 510-8, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20382720

ABSTRACT

BACKGROUND: Spontaneous pneumothorax (SPTX) is an uncommon phenomenon in the general population and is most commonly associated with prior bulbous emphysema, cystic parenchymal lung disease, and tuberculous lung disease. A rare cause of SPTX is malignant disease, either in the form of primary lung or pleural cancers, or in metastatic disease to the lungs. The purpose of this investigation was to compile patient characteristics, treatments received, and outcomes of patients with SPTX complicating sarcomatous cancer. METHODS: Case reports and series published in the medical literature were identified through a MEDLINE search and compiled to determine similarities among patient characteristics, treatments received, and outcomes. RESULTS: One hundred fifty-three cases representing 20 different sarcoma cell types were included; 126 (82.3%) had received some form of treatment prior to the development of pneumothorax, and 70 (45.7%) experienced recurrence of pneumothorax at an average of 61 (+/- 112) days. Patients had poor survival, with only seven of 81 subjects remaining alive 2 years after the initial diagnosis of SPTX. CONCLUSIONS: SPTX complicating sarcoma is associated with most cell types and is associated with increased mortality compared with patients without this complication.


Subject(s)
Lung Neoplasms/complications , Pleural Neoplasms/complications , Pneumothorax/etiology , Sarcoma/complications , Humans , Lung Neoplasms/pathology , Lung Neoplasms/therapy , Pleural Neoplasms/pathology , Pleural Neoplasms/therapy , Pneumothorax/diagnosis , Pneumothorax/therapy , Sarcoma/pathology , Sarcoma/therapy
8.
J Bronchology Interv Pulmonol ; 17(2): 131-5, 2010 Apr.
Article in English | MEDLINE | ID: mdl-23168728

ABSTRACT

Although significant experience exists in placing airway stents, and knowledge of stent-related complications is widespread, information is lacking regarding methods of surveillance and maintaining patency of these stents. The purpose of this investigation was to determine the actual practice patterns used by interventional pulmonologists for airway stent maintenance. We prospectively surveyed members of the American Association of Bronchology and Interventional Pulmonology or attendees at their annual meeting during Chest 2008. Sixty-two respondents returned the completed surveys and were included in the analysis. Practice settings included university (50%), single specialty (27%), community academic (11%), and multispecialty (11%) settings. Annual placement of stents was ≤10 (31%); 11 to 30 (45%); and >30 (24%). Considerable variability existed in both medications used for maintenance and surveillance schedules, and less than 50% protocolized postplacement management. Although stent placement is common among experienced interventional pulmonologists, half have no protocol for surveillance or maintenance. Similarly, there is no discernable consistency or standard practice pattern to monitor for or prevent stent failure. Further study is required to determine the best practices for postdeployment surveillance and maintenance of airway stents.

10.
Ecotoxicol Environ Saf ; 72(8): 2046-57, 2009 11.
Article in English | MEDLINE | ID: mdl-19767103

ABSTRACT

Pit lakes are increasingly common worldwide and have potential to provide many benefits. However, lake water toxicity may require remediation before beneficial end uses can be realised. Three treatments to remediate AMD (pH approximately 4.8) pit lake water containing elevated concentrations of Al and Zn from Collie, Western Australia were tested in mesocosms. Treatments were: (a) limestone neutralisation (L), (b) phosphorus amendment (P), and (c) combined limestone neutralisation and phosphorus amendment (L+P). Laboratory bioassays with Ceriodaphnia cf. dubia, Chlorella protothecoides and Tetrahymena thermophila assessed remediation. Limestone neutralisation increased pH and reduced heavy metal concentrations by 98% (Al) to 14% (Mg), removing toxicity to the three test species within 2 months. Phosphorus amendment removed toxicity after 6 months of treatment. However, phosphorus amendment to prior limestone neutralisation failed to reduce toxicity more than limestone neutralisation alone. Low concentrations of both phosphorus and nitrogen appear to limit phytoplankton population growth in all treatments.


Subject(s)
Calcium Carbonate/chemistry , Environmental Restoration and Remediation/methods , Fresh Water/chemistry , Metals, Heavy/toxicity , Phosphorus/chemistry , Water Pollutants, Chemical/toxicity , Acids/analysis , Acids/toxicity , Aluminum/analysis , Aluminum/toxicity , Biological Assay , Environmental Monitoring , Hydrogen-Ion Concentration , Kinetics , Metals, Heavy/analysis , Mining , Nitrogen/analysis , Phosphorus/analysis , Phytoplankton/drug effects , Phytoplankton/growth & development , Phytoplankton/metabolism , Toxicity Tests, Chronic , Water Pollutants, Chemical/analysis , Zinc/analysis , Zinc/toxicity
11.
J Exp Clin Cancer Res ; 28: 113, 2009 Aug 14.
Article in English | MEDLINE | ID: mdl-19682368

ABSTRACT

Compounds derived from biologic sources, or biologicals, are increasingly utilized as therapeutic agents in malignancy. Development of anti-cancer targeted therapies from biologics is increasingly being utilized. Cetuximab, a chimeric monoclonal antibody, is one such anti-cancer targeted therapeutic that has shown efficacy in quelling the rate of patient decline in colorectal, head/neck, and non-small cell lung cancer. However, due to the relatively recent addition of biologic compounds to the therapeutic arsenal, information related to adverse reactions is less well known than those seen in traditional chemotherapeutics. Dermatologic reactions have been demonstrated as the most frequent side effect cited during cetuximab therapy for malignancy; however, other effects may lead to greater morbidity. In general, pulmonary complications of therapeutics can lead to significant morbidity and mortality. The purpose of this review is to compile the various pulmonary side effects seen in patients treated with cetuximab for various malignancies, and to compare the incidence of these adverse reactions to standard therapies.


Subject(s)
Antibodies, Monoclonal/adverse effects , Antineoplastic Agents/adverse effects , Lung/drug effects , Neoplasms/drug therapy , Antibodies, Monoclonal/therapeutic use , Antibodies, Monoclonal, Humanized , Antineoplastic Agents/therapeutic use , Cetuximab , Humans , Lung/pathology
14.
Chest ; 131(2): 579-87, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17296664

ABSTRACT

BACKGROUND: Airway stenting is a procedure that is performed increasingly often, and the availability of metallic stents placed by flexible bronchoscopy may have contributed to the increased usage. These procedures have an impact on the required physician skill set and practice management. We review the indications for airway stenting, and how the requirement of combined therapies and technical aspects of central airway stenting pertain to practice management. PROCEDURE: We compared several reimbursement scenarios for managing stent placement using the Centers for Medicare and Medicaid Services relative value units (RVUs) and average reimbursement amounts. We also compared the reimbursement to other commonly performed activities performed by pulmonary and critical care physicians. An analysis of Medicare facility outpatient and inpatient payment for procedures using silicone and metallic stents was also conducted. RESULTS: Professional reimbursement is identical regardless of stent type, method of insertion, and anesthesia administered. The net facility reimbursement largely depends on stent costs. The RVUs alone are a poor comparator for the reimbursement of therapeutic bronchoscopy because of Correct Coding Initiatives edits. Considering the time necessary for performing advanced therapeutic bronchoscopy, the professional fees are not attractive. The net facility reimbursement largely depends on stent costs. CONCLUSION: The placement of airway stents is not reimbursed at competitive rates and may even lead to a net loss for the facility. The practice management benefits of central airway therapy are probably best obtained by a multidisciplinary airway team with an established cost center structure.


Subject(s)
Airway Obstruction/therapy , Bronchoscopy/economics , Insurance, Health, Reimbursement/economics , Medicare/economics , Prosthesis Implantation/economics , Stents/economics , Airway Obstruction/etiology , Equipment Design , Humans
15.
Respiration ; 73(1): 78-89, 2006.
Article in English | MEDLINE | ID: mdl-16498271

ABSTRACT

BACKGROUND AND OBJECTIVE: Transbronchial needle catheters are commonly used during flexible and rigid bronchoscopy for needle aspiration. The use of these catheters can be expanded by employing the technique of transbronchial needle injection. METHODS AND RESULTS: By injecting lesions in the airways, peribronchial structures, mediastinum, or lung parenchyma, transbronchial needle injection has been applied to the treatment of lung cancer, inflammatory disorders of the airways, recurrent respiratory papillomatosis, as well as bronchopleural fistulas. Diagnostic applications have included the localization of peripheral lung nodules as well as sentinel lymph nodes. CONCLUSIONS: Our review defines this bronchoscopic technique and summarizes its various reported applications.


Subject(s)
Bronchoscopy/methods , Catheterization , Cytosine/analogs & derivatives , Lung Diseases/diagnosis , Lung Diseases/therapy , Organophosphonates/administration & dosage , Bronchoscopy/adverse effects , Cidofovir , Cytosine/administration & dosage , Equipment Design , Humans , Injections , Lung Neoplasms/therapy , Papilloma/drug therapy , Respiratory Tract Neoplasms/drug therapy , Secondary Prevention , Solitary Pulmonary Nodule/diagnosis , Thoracic Neoplasms/therapy
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