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1.
Gut Pathog ; 12: 14, 2020.
Article in English | MEDLINE | ID: mdl-32175011

ABSTRACT

BACKGROUND: The rise of nature-based ecotourism in the past decade has introduced unprecedented challenges in managing the increasing interaction between humans and animals. The potential transmission of antibiotic resistant microbes between humans and non-human primate populations is a concern due to their genetic similarity. Malaysia is well known for hotspots of wildlife diversity where non-human primates like monkeys and orangutans have become popular tourist attractions. In this study, we assessed the prevalence of antimicrobial resistant Staphylococcus aureus, Enterococcus species, and other Enterobacteriaceae in the faeces of human (HS) and two non-human primates (NHP) in Malaysia, the Long-tailed macaque (Macaca fascicularis, MF) and Silvered leaf monkey (Trachypithecus cristatus, TC). In addition, the faecal bacterial composition was profiled to evaluate the potential association between antibiotic resistant profiles and composition of gut microbiota. RESULTS: We tested the isolated bacteria using a selection of antibiotics. The results showed that both the number of antibiotic resistant strains and resistance level were higher in humans than NHPs. Overall, the composition of gut microbiome and pattern of antibiotic resistance showed that there was higher similarity between MF and TC, the two NHPs, than with HS. In addition, samples with higher levels of antibiotic resistance showed lower bacterial richness. Homo sapiens had the lowest bacterial diversity and yet it had higher abundance of Bacteroides. In contrast, NHPs displayed higher bacterial richness and greater prevalence of Firmicutes such as Ruminococceae and Oscillospira. CONCLUSION: Higher antibiotic susceptibility in NHPs is likely related to low direct exposure to antibiotics. The lack of resistance may also suggest limited antimicrobial resistance transmission between humans and NHP. Nonetheless, continued monitoring over a long period will help mitigate the risk of anthropozoonosis and zooanthroponosis.

2.
BJOG ; 127(4): 490-499, 2020 03.
Article in English | MEDLINE | ID: mdl-31778255

ABSTRACT

OBJECTIVE: To determine the association between maternal lipaemia and neonatal anthropometrics in Malaysian mother-offspring pairs. DESIGN: Prospective observational cohort study. SETTING: Single tertiary multidisciplinary antenatal clinic in Malaysia. POPULATION: A total of 507 mothers: 145 with gestational diabetes mellitus (GDM); 94 who were obese with normal glucose tolerance (NGT) (pre-gravid body mass index, BMI ≥ 27.5 kg/m2 ), and 268 who were not obese with NGT. METHODS: Maternal demographic, anthropometric, and clinical data were collected during an interview/examination using a structured questionnaire. Blood was drawn for insulin, C-peptide, triglyceride (Tg), and non-esterified fatty acid (NEFA) during the 75-g 2-hour oral glucose tolerance test (OGTT) screening, and again at 36 weeks of gestation. At birth, neonatal anthropometrics were assessed and data such as gestational weight gain (GWG) were extracted from the records. MAIN OUTCOME MEASURES: Macrosomia, large-for-gestational-age (LGA) status, cohort-specific birthweight (BW), neonatal fat mass (NFM), and sum of skinfold thickness (SSFT) > 90th centile. RESULTS: Fasting Tg > 95th centile (3.6 mmol/L) at screening for OGTT was independently associated with LGA (adjusted odds ratio, aOR 10.82, 95% CI 1.26-93.37) after adjustment for maternal glucose, pre-gravid BMI, and insulin sensitivity. Fasting glucose was independently associated with a birthweight ratio (BWR) of >90th centile (aOR 2.06, 95% CI 1.17-3.64), but not with LGA status, in this well-treated GDM cohort with pre-delivery HbA1c of 5.27%. In all, 45% of mothers had a pre-gravid BMI of <23 kg/m2 and 61% had a pre-gravid BMI of ≤ 25 kg/m2 , yet a GWG of >10 kg was associated with a 4.25-fold risk (95% CI 1.71-10.53) of BWR > 90th centile. CONCLUSION: Maternal lipaemia and GWG at a low threshold (>10 kg) adversely impact neonatal adiposity in Asian offspring, independent of glucose, insulin resistance and pre-gravid BMI. These may therefore be important modifiable metabolic targets in pregnancy. TWEETABLE ABSTRACT: Maternal lipids are associated with adiposity in Asian babies independently of pre-gravid BMI, GDM status, and insulin resistance.


Subject(s)
Birth Weight , Fetal Macrosomia/blood , Hyperlipidemias/blood , Adult , Asian People , Body Mass Index , Case-Control Studies , Female , Fetal Macrosomia/epidemiology , Humans , Hyperlipidemias/complications , Infant, Newborn , Malaysia/epidemiology , Male , Obesity/epidemiology , Pregnancy , Prospective Studies , Surveys and Questionnaires , Triglycerides/blood
3.
Diabet Med ; 35(8): 1118-1129, 2018 08.
Article in English | MEDLINE | ID: mdl-29663517

ABSTRACT

AIMS: To determine if therapeutic, retrospective continuous glucose monitoring (CGM) improves HbA1c with less hypoglycaemia in women with insulin-treated gestational diabetes mellitus (GDM). METHODS: This prospective, randomized controlled, open-label trial evaluated 50 women with insulin-treated GDM randomized to either retrospective CGM (6-day sensor) at 28, 32 and 36 weeks' gestation (Group 1, CGM, n = 25) or usual antenatal care without CGM (Group 2, control, n = 25). All women performed seven-point capillary blood glucose (CBG) profiles at least 3 days per week and recorded hypoglycaemic events (symptomatic and asymptomatic CBG < 3.5 mmol/l; non-fasting < 4.0 mmol/l). HbA1c was measured at 28, 33 and 37 weeks. In Group 1, both CGM and CBG data were used to manage diabetes, whereas mothers in Group 2 were managed based on CBG data alone. RESULTS: Baseline characteristics (age, pre-pregnancy BMI, HbA1c , total insulin dose) were similar between groups. There was a lower increase in HbA1c from 28 to 37 weeks' gestation in the CGM group [∆HbA1c : CGM + 1 mmol/mol (0.09%), control + 3mmol/mol (0.30%); P = 0.024]. Mean HbA1c remained unchanged throughout the trial in the CGM group, but increased significantly in controls as pregnancy advanced. Mean HbA1c in the CGM group was lower at 37 weeks compared with controls [33 ± 4 mmol/mol (5.2 ± 0.4%) vs. 38 ± 7 mmol/mol (5.6 ± 0.6%), P < 0.006]. Some 92% of the CGM group achieved an HbA1c ≤ 39 mmol/mol (≤ 5.8%) at 37 weeks compared with 68% of the control group (P = 0.012). Neither group experienced severe hypoglycaemia. CONCLUSION: CGM use may be beneficial in insulin-treated GDM because it improves HbA1c compared with usual antenatal care without increasing severe hypoglycaemia. (Clinical Trials Registry No.: NCT02204657).


Subject(s)
Blood Glucose/analysis , Diabetes, Gestational/blood , Diabetes, Gestational/drug therapy , Glycated Hemoglobin/metabolism , Insulin/therapeutic use , Adult , Blood Glucose/drug effects , Blood Glucose/metabolism , Blood Glucose Self-Monitoring/instrumentation , Blood Glucose Self-Monitoring/methods , Female , Glycated Hemoglobin/analysis , Glycated Hemoglobin/drug effects , Humans , Malaysia , Pregnancy , Prenatal Care/methods , Standard of Care
4.
Article in English | MEDLINE | ID: mdl-28929537

ABSTRACT

Registry data on invasive cervical cancers (n = 1,274) from four major hospitals (1984-2012) were analysed to determine their value for informing local service delivery in Australia. The methodology comprised disease-specific survival analyses using Kaplan-Meier product-limit estimates and Cox proportional hazards models and treatment analyses using logistic regression. Five- and 10-year survivals were 72% and 68%, respectively, equating with relative survival estimates for Australia and the USA. Most common treatments were surgery and radiotherapy. Systemic therapies increased in recent years, generally with radiotherapy, but were less common for residents from less accessible areas. Surgery was more common for younger women and early-stage disease, and radiotherapy for older women and regional and more advanced disease. The proportion of glandular cancers increased in-step with national trends. Little evidence of variation in risk-adjusted survival presented over time or by Local Health District. The study illustrates the value of local registry data for describing local treatment and outcomes. They show the lower use of systemic therapies among residents of less accessible areas which warrants further investigation. Risk-adjusted treatment and outcomes did not vary by socio-economic status, suggesting equity in service delivery. These data are important for local evaluation and were not available from other sources.


Subject(s)
Adenocarcinoma/therapy , Carcinoma, Squamous Cell/therapy , Health Services Accessibility , Hysterectomy , Radiotherapy , Registries , Uterine Cervical Neoplasms/therapy , Adenocarcinoma/mortality , Adult , Aged , Aged, 80 and over , Australia , Carcinoma, Squamous Cell/mortality , Databases, Factual , Delivery of Health Care , Disease Management , Female , Humans , Kaplan-Meier Estimate , Logistic Models , Middle Aged , Outcome Assessment, Health Care , Proportional Hazards Models , Survival Analysis , Survival Rate , Uterine Cervical Neoplasms/mortality
5.
AJNR Am J Neuroradiol ; 37(6): 1092-8, 2016 Jun.
Article in English | MEDLINE | ID: mdl-26797140

ABSTRACT

BACKGROUND AND PURPOSE: Spontaneous or progressive occlusion of the posterior fossa dural sinuses is often observed in patients with vein of Galen malformation, which can affect the clinical course. The aim of this study was to examine the patency of the posterior fossa dural sinuses in patients with vein of Galen malformation and to analyze the clinical and angiographic course of this condition. MATERIALS AND METHODS: We retrospectively reviewed 61 consecutive children with vein of Galen malformations. Clinical presentation, management, outcome, and angiographic change were analyzed for the patients with attention paid to all dural sinus occlusions. RESULTS: Twenty patients (32.8%) demonstrated spontaneous sinus occlusion, mostly in the sigmoid sinus. This condition was not observed in neonates and was first discovered during infancy or childhood. Progression of sinus occlusion was seen in 10 patients, and the conditions of 6 of them deteriorated in accordance with the progression of sinus occlusion. After total or subtotal obliteration of the malformation by transarterial glue embolization, 13 patients recovered to healthy, 3 patients had only mild developmental delay, and 4 patients remained neurologically disabled. CONCLUSIONS: Spontaneous sinus occlusion is not a rare condition and can result in neurologic deterioration in the natural history of untreated vein of Galen malformation. If signs of progressive sinus occlusion are noticed, early arteriovenous shunt reduction or elimination by transarterial glue embolization is expected to prevent permanent brain damage.


Subject(s)
Cranial Fossa, Posterior/pathology , Cranial Sinuses/pathology , Vein of Galen Malformations/pathology , Adolescent , Arteriovenous Shunt, Surgical , Child , Child, Preschool , Disease Progression , Embolization, Therapeutic , Endovascular Procedures , Female , Humans , Infant , Infant, Newborn , Male , Nervous System Diseases/etiology , Retrospective Studies , Treatment Outcome , Vein of Galen Malformations/complications , Vein of Galen Malformations/therapy
6.
Trop Biomed ; 33(4): 746-752, 2016 Dec 01.
Article in English | MEDLINE | ID: mdl-33579071

ABSTRACT

Dengue infection is endemic in South East Asia and parts of the Americas. Dengue hemorrhagic fever is characterized by vascular permeability, coagulation-disorders and thrombocytopenia, which can culminate in hypotension i.e. dengue shock syndrome. Hypopituitarism arising as a complication of dengue is extremely rare. Hemorrhagic pituitary apoplexy of pre-existing pituitary adenomas has been rarely reported in dengue. We describe an uncommon case of hypopituitarism in a dengue shock syndrome survivor without known pituitary adenoma. A 49 years old nulliparous lady (from Kuala Lumpur, Malaysia) presented with typical symptoms of hypocortisolism. Postural hypotension was evident with normal secondary sexual characteristics. Further history revealed that she survived an episode of dengue shock syndrome 6 years ago where premature menopause developed immediately after discharge, and subsequently insidious onset of multiple hormonal deficiencies indicative of panhypopituitarism. There were no neuro-ophthalmological symptoms suggestive of pituitary apoplexy during hospitalization for severe dengue. Magnetic resonance imaging of the pituitary 6 years later revealed an empty sella. Autoimmune screen and anti-thyroid peroxidase antibodies were negative. We describe a rare possible causative association of severe dengue with panhypopituitarism without known pituitary adenoma, postulating pituitary infarction secondary to hypotension (mimicking Sheehan's syndrome), or a direct viral cytopathic effect. Subclinical pituitary apoplexy secondary to asymptomatic pituitary hemorrhage however cannot be excluded. Future research is required to determine the need for and timing of pituitary axis assessment among dengue shock syndrome survivors.

7.
Tropical Biomedicine ; : 746-752, 2016.
Article in English | WPRIM (Western Pacific) | ID: wpr-630854

ABSTRACT

Dengue infection is endemic in South East Asia and parts of the Americas. Dengue hemorrhagic fever is characterized by vascular permeability, coagulation-disorders and thrombocytopenia, which can culminate in hypotension i.e. dengue shock syndrome. Hypopituitarism arising as a complication of dengue is extremely rare. Hemorrhagic pituitary apoplexy of pre-existing pituitary adenomas has been rarely reported in dengue. We describe an uncommon case of hypopituitarism in a dengue shock syndrome survivor without known pituitary adenoma. A 49 years old nulliparous lady (from Kuala Lumpur, Malaysia) presented with typical symptoms of hypocortisolism. Postural hypotension was evident with normal secondary sexual characteristics. Further history revealed that she survived an episode of dengue shock syndrome 6 years ago where premature menopause developed immediately after discharge, and subsequently insidious onset of multiple hormonal deficiencies indicative of panhypopituitarism. There were no neuro-ophthalmological symptoms suggestive of pituitary apoplexy during hospitalization for severe dengue. Magnetic resonance imaging of the pituitary 6 years later revealed an empty sella. Autoimmune screen and anti-thyroid peroxidase antibodies were negative. We describe a rare possible causative association of severe dengue with panhypopituitarism without known pituitary adenoma, postulating pituitary infarction secondary to hypotension (mimicking Sheehan’s syndrome), or a direct viral cytopathic effect. Subclinical pituitary apoplexy secondary to asymptomatic pituitary hemorrhage however cannot be excluded. Future research is required to determine the need for and timing of pituitary axis assessment among dengue shock syndrome survivors.

8.
Pituitary ; 18(4): 448-55, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25134488

ABSTRACT

PURPOSE: Radiation fields for nasopharyngeal cancer (NPC) include the base of skull, which places the hypothalamus and pituitary at risk of damage. We aimed to establish the prevalence, pattern and severity of hypothalamic pituitary (HP) dysfunction amongst NPC survivors. METHODS: We studied 50 patients (31 males) with mean age 57 ± 12.2 years who had treatment for NPC between 3 and 21 years (median 8 years) without pre-existing HP disorder from other causes. All patients had a baseline cortisol, fT4, TSH, LH, FSH, oestradiol/testosterone, prolactin and renal function. All patients underwent dynamic testing with insulin tolerance test to assess the somatotroph and corticotroph axes. Baseline blood measurements were used to assess thyrotroph, gonadotroph and lactotroph function. RESULTS: Hypopituitarism was present in 82% of patients, 30% single axis, 28% two axes, 18% three axes and 6% four axes deficiencies. Somatotroph deficiency was most common (78%) while corticotroph, gonadotroph and thyrotroph deficiencies were noted in 40% (4 complete/16 partial), 22 and 4% of the patients respectively. Hyperprolactinaemia was present in 30% of patients. The development of HP dysfunction was significantly associated with the time elapsed from irradiation, OR 2.5 (1.2, 5.3), p = 0.02, for every 2 years post treatment. The use of concurrent chemo-irradiation (CCRT) compared to those who had radiotherapy alone was also significantly associated with HP dysfunction, OR 14.5 (2.4, 87.7), p < 0.01. CONCLUSION: Despite low awareness and detection rates, HP dysfunction post-NPC irradiation is common. Use of CCRT may augment time related pituitary damage. As these endocrinopathies result in significant morbidity and mortality we recommend periodic assessment of pituitary function amongst NPC survivors.


Subject(s)
Human Growth Hormone/deficiency , Hyperprolactinemia/epidemiology , Hypopituitarism/epidemiology , Hypothalamo-Hypophyseal System , Nasopharyngeal Neoplasms/therapy , Survivors , Aged , Chemoradiotherapy , Cross-Sectional Studies , Estradiol/blood , Female , Follicle Stimulating Hormone/blood , Humans , Hydrocortisone/blood , Hyperprolactinemia/blood , Hypogonadism/blood , Hypogonadism/epidemiology , Hypopituitarism/blood , Hypothyroidism/blood , Hypothyroidism/epidemiology , Luteinizing Hormone/blood , Male , Middle Aged , Organs at Risk , Prolactin/blood , Radiotherapy , Testosterone/blood , Thyrotropin/blood , Thyroxine/blood
9.
Article in English | MEDLINE | ID: mdl-24046559

ABSTRACT

In the title compound, [Fe(C5H5)(C14H10NO3)], the cyclo-penta-dienyl rings are in an eclipsed conformation and the pyran ring adopts a half-chair conformation. The mean plane of the pyran ring makes dihedral angles of 79.33 (1) and 80.73 (1)°, respectively, with the substituted and unsubstituted cyclo-penta-dienyl rings. In the crystal, pairs of C-H⋯O hydrogen bonds link the mol-ecules into inversion dimers with R 2 (2)(16) motifs.

10.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 5): o664, 2013 May 01.
Article in English | MEDLINE | ID: mdl-23723826

ABSTRACT

The title compound, C19H17NO5, comprising two stereogenic C atoms of the same configuration, crystallizes in a centrosymmetric space group as a racemate. The pyran ring adopts a half-chair conformation, while the isoxazole ring adopts an envelope conformation with the C atom bonded to the meth-oxy-phenyl group as the flap. The dihedral angle between the mean plane of the pyran ring and the adjacent benzene ring is 5.86 (5)°. In the crystal, mol-ecules are linked by a weak C-H⋯O hydrogen bond, forming a chain along the a axis.

11.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 5): o716, 2013 May 01.
Article in English | MEDLINE | ID: mdl-23723869

ABSTRACT

The title compound, C17H11ClN2O2, which contains two stereogenic C atoms, crystallizes in a centrosymmetric space group as a racemate. The pyran ring and the isoxazole ring adopt sofa and twisted conformations, respectively. The dihedral angle between the benzene ring and the mean plane through the near coplanar atoms of the pyran ring is 4.17 (5)°. The mol-ecular conformation features a weak C-H⋯O contact. In the crystal, C-H⋯O hydrogen bonds link the mol-ecules, forming chains along the a-axis direction.

12.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 3): m144, 2013 Mar 01.
Article in English | MEDLINE | ID: mdl-23476492

ABSTRACT

In the title compound, [Fe(C5H5)(C16H15O3)], the cyclo-penta-dienyl rings are in an eclipsed conformation and the benzene ring makes dihedral angles of 10.84 (9) and 12.35 (9)°, respectively, with the substituted and unsubstituted cyclo-penta-dienyl rings. In the crystal, mol-ecules form inversion dimers through pairs of O-H⋯O hydrogen bonds. Weak C-H⋯O hydrogen bonds are observed between the dimers.

13.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 2): o314-5, 2013 Feb 01.
Article in English | MEDLINE | ID: mdl-23424579

ABSTRACT

In the title compound, C(28)H(24)ClNO(3), the dihedral angles between the central benzene ring and the indole ring system and the chlorobenzene ring are 70.81 (5) and 78.62 (5)°, respectively. The mol-ecular structure is stabilized by a weak intra-molecular C-H⋯O inter-action. In the crystal, pairs of C-H⋯O hydrogen bonds link the mol-ecules into inversion dimers with an R(2) (2)(14) motif.

15.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 7): o1987, 2012 Jul 01.
Article in English | MEDLINE | ID: mdl-22807820

ABSTRACT

The title compound, C(25)H(23)NO(5), comprising two stereogenic carbon atoms of the same configuration, crystallizes in a centrosymmetric space group as a racemate. The six-membered pyran ring and the five-membered isoxazole ring adopt sofa and twisted conformations, respectively. The dihedral angle between the benzene ring and the mean plane through the near coplanar atoms of the pyran ring is 10.73 (7)°. The crystal structure features C-H⋯O hydrogen bonds.

16.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 6): o1660, 2012 Jun 01.
Article in English | MEDLINE | ID: mdl-22719456

ABSTRACT

The title compound, C(25)H(22)N(2)O(3), with three stereogenic centres, crystallizes in a centrosymmetric space group as a racemate. The pyran ring adopts a sofa conformation and the five-membered isoxazole ring exhibits an envelope conformation. The dihedral angle between the benzene ring and the mean plane through the near coplanar atoms of the pyran ring is 10.54 (9)°. In the crystal, no significant intermolecular interactions are observed.

17.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 3): o683-4, 2012 Mar 01.
Article in English | MEDLINE | ID: mdl-22412578

ABSTRACT

In the title compound, C(25)H(18)N(2)O(3)S, the indole moiety is planar and makes a dihedral angle of 89.95 (09)° with the phenyl ring of the sulfonyl substituent. The mol-ecular conformation features a weak C-H⋯N short contact and the crystal packing reveals a weak C-H⋯O hydrogen bond.

18.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 2): o506, 2012 Feb 01.
Article in English | MEDLINE | ID: mdl-22347107

ABSTRACT

The cyclo-hexene ring in the title compound, C(15)H(18)INO(2), adopts a sofa conformation. The dihedral angle between the cyclo-hexene (through all ring atoms) and benzene rings is 63.3 (1)°. The mol-ecular conformation features an N-H⋯I short contact and the crystal packing features C-H⋯O hydrogen bonds.

19.
J Environ Sci Health B ; 44(3): 317-24, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19280486

ABSTRACT

Ammonia (NH(3)) emission from livestock manures used in agriculture reduces N uptake by crops and negatively impacts air quality. This laboratory study was conducted to evaluate NH(3)emission from different livestock manures applied to two soils: Candler fins sand (CFS; light-textured soil, pH 6.8 and field capacity soil water content of 70 g kg(-1)) from Lake Alfred, Florida and Ogeechee loamy sand (OLS; medium-textured soil, pH 5.2 and field capacity soil water content of 140 g kg(-1)) from Savannah, Georgia. Poultry litter (PL) collected from a poultry farm near Douglas, Georgia, and fresh solid separate of swine manure (SM) collected from a farm near Clinton, North Carolina were used. Each of the soil was weighed in 100 g sub samples and amended with either PL or SM at rates equivalent to either 0, 2.24, 5.60, 11.20, or 22.40 Mg ha(-1) in 1L Mason jars and incubated in the laboratory at field capacity soil water content for 19 days to monitor NH(3) volatilization. Results indicated a greater NH(3) loss from soils amended with SM compared to that with PL. The cumulative NH(3)volatilization loss over 19 days ranged from 4 to 27% and 14 to 32% of total N applied as PL and SM, respectively. Volatilization of NH(3) was greater from light-textured CFS than that from medium-textured OLS. Volatilization loss increased with increasing rates of manure application. Ammonia volatilization was lower at night time than that during the day time. Differences in major factors such as soil water content, temperature, soil type and live stock manure type influenced the diurnal variation in volatilization loss of NH(3) from soils. A significant portion (> 50%) of cumulative NH(3) emission over 19 d occurred during the first 5-7 d following the application of livestock manures. Results of this study demonstrate that application of low rates of livestock manure (< or = 5.60 Mg ha(-1)) is recommended to minimize NH(3) emissions.


Subject(s)
Air Pollutants/chemistry , Ammonia/chemistry , Manure/analysis , Animals , Environmental Monitoring , Poultry , Swine , Volatilization
20.
Article in English | MEDLINE | ID: mdl-18172810

ABSTRACT

Increase in concentrations of various greenhouse gases and their possible contributions to the global warming are becoming a serious concern. Anthropogenic activities such as cultivation of flooded rice and application of waste materials, such as sewage sludge which are rich in C and N, as soil amendments could contribute to the increase in emission of greenhouse gases such as methane (CH(4)) and nitrous oxide (N(2)O) into the atmosphere. Therefore, evaluation of flux of various greenhouse gases from soils amended with sewage sludge is essential to quantify their release into the atmosphere. Two soils with contrasting properties (Candler fine sand [CFS] from Florida, and Ogeechee loamy sand [OLS] from Savannah, GA) were amended with varying rates (0, 24.7, 49.4, 98.8, and 148.3 Mg ha(-1)) of 2 types of sewage sludge (industrial [ISS] and domestic [DSS] origin. The amended soil samples were incubated in anaerobic condition at field capacity soil water content in static chamber (Qopak bottles). Gas samples were extracted immediately after amending soils and subsequently on a daily basis to evaluate the emission of CH(4), CO(2) and N(2)O. The results showed that emission rates and cumulative emission of all three gases increased with increasing rates of amendments. Cumulative emission of gases during 25-d incubation of soils amended with different types of sewage sludge decreased in the order: CO(2) > N(2)O > CH(4). The emission of gases was greater from the soils amended with DSS as compared to that with ISS. This may indicate the presence of either low C and N content or possible harmful chemicals in the ISS. The emission of gases was greater from the CFS as compared to that from the OLS. Furthermore, the results clearly depicted the inhibitory effect of acetylene in both soils by producing more N(2)O and CH(4) emission compared to the soils that did not receive acetylene at the rate of 1 mL g(-1) soil. Enumeration of microbial population by fluorescein diacetate (FDA) and most probable number (MPN) procedure at the end of 25-d incubation demonstrated a clear relationship between microbial activity and the emission of gases. The results of this study emphasize the need to consider the emission of greenhouse gases from soils amended with organic soil amendments such as sewage sludge, especially at high rates, and their potential contribution to global warming.


Subject(s)
Air Pollutants/analysis , Air , Gases/analysis , Greenhouse Effect , Sewage/chemistry , Soil/analysis , Air/analysis , Air/standards , Environmental Monitoring , United States
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