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Fulltext Switching from monoculture to polyculture farming benefits birds in oil palm production landscapes: Evidence from mist netting data

Yahya MS, Syafiq M, Ashton-Butt A, Ghazali A, Asmah S, Azhar B

Ecol Evol, 2017 08;7(16):6314-6325.
PMID: 28861235 DOI: 10.1002/ece3.3205

Monoculture farming is pervasive in industrial oil palm agriculture, including those RSPO plantations certified as sustainably managed. This farming practice does not promote the maintenance of farmland biodiversity. However, little scientific attention has been given to polyculture farming in oil palm production landscapes. Polyculture farming is likely to increase the floristic diversity and stand structural complexity that underpins biodiversity. Mist nets were used to sample birds at 120 smallholdings in Peninsular Malaysia. At each site, 12 vegetation structure characteristics were measured. We compared bird species richness, abundance, and composition between monoculture and polyculture smallholdings and used predictive models to examine the effects of habitat quality on avian biodiversity. Bird species richness was significantly greater in polyculture than that of monoculture smallholdings. The number of fallen and standing, dead oil palms were also important positive predictors of species richness. Bird abundance was also strongly increased by standing and dead oil palms and decreased with oil palm stand height. Our results indicate that polyculture farming can improve bird species richness in oil palm production landscapes. In addition, key habitat variables that are closely associated with farming practices, such as the removal of dead trees, should and can be managed by oil palm growers in order to promote biodiversity. To increase the sustainability of oil palm agriculture, it is imperative that stakeholders modify the way oil palms are currently planted and managed. Our findings can guide policy makers and certification bodies to promote oil palm production landscapes that will function more sustainably and increase existing biodiversity of oil palm landscapes.
Fulltext Land use conversion from peat swamp forest to oil palm agriculture greatly modifies microclimate and soil conditions

Anamulai S, Sanusi R, Zubaid A, Lechner AM, Ashton-Butt A, Azhar B

PeerJ, 2019;7:e7656.
PMID: 31632845 DOI: 10.7717/peerj.7656

Oil palm (Elaeis guineensis) agriculture is rapidly expanding and requires large areas of land in the tropics to meet the global demand for palm oil products. Land cover conversion of peat swamp forest to oil palm (large- and small-scale oil palm production) is likely to have negative impacts on microhabitat conditions. This study assessed the impact of peat swamp forest conversion to oil palm plantation on microclimate conditions and soil characteristics. The measurement of microclimate (air temperature, wind speed, light intensity and relative humidity) and soil characteristics (soil surface temperature, soil pH, soil moisture, and ground cover vegetation temperature) were compared at a peat swamp forest, smallholdings and a large-scale plantation. Results showed that the peat swamp forest was 1.5-2.3 °C cooler with significantly greater relative humidity, lower light intensities and wind speed compared to the smallholdings and large-scale plantations. Soil characteristics were also significantly different between the peat swamp forest and both types of oil palm plantations with lower soil pH, soil and ground cover vegetation surface temperatures and greater soil moisture in the peat swamp forest. These results suggest that peat swamp forests have greater ecosystem benefits compared to oil palm plantations with smallholdings agricultural approach as a promising management practice to improve microhabitat conditions. Our findings also justify the conservation of remaining peat swamp forest as it provides a refuge from harsh microclimatic conditions that characterize large plantations and smallholdings.
Fulltext Urban forest fragmentation impoverishes native mammalian biodiversity in the tropics

Tee SL, Samantha LD, Kamarudin N, Akbar Z, Lechner AM, Ashton-Butt A, et al.

Ecol Evol, 2018 Dec;8(24):12506-12521.
PMID: 30619561 DOI: 10.1002/ece3.4632

Urban expansion has caused major deforestation and forest fragmentation in the tropics. The impacts of habitat fragmentation on biodiversity are understudied in urban forest patches, especially in the tropics and little is known on the conservation value of the patches for maintaining mammalian biodiversity. In this study, camera trapping was used to determine the species composition and species richness of medium- and large-sized mammals in three urban forest patches and a contiguous forest in Peninsular Malaysia. We identified the key vegetation attributes that predicted mammal species richness and occurrence of herbivores and omnivores in urban forest patches. A total number of 19 mammal species from 120 sampling points were recorded. Contiguous forest had the highest number of species compared to the urban forest patches. Sunda Pangolin and Asian Tapir were the only conservation priority species recorded in the urban forest patches and contiguous forest, respectively. Top predators such as Malayan Tiger and Melanistic Leopard were completely absent from the forest patches as well as the contiguous forest. This was reflected by the abundance of wild boars. We found that mammal species richness increased with the number of trees with DBH less than 5 cm, trees with DBH more than 50 cm, and dead standing trees. In the future, the remaining mammal species in the urban forest patches are expected to be locally extinct as connecting the urban forest patches may be infeasible due to land scarcity. Hence, to maintain the ecological integrity of urban forest patches, we recommend that stakeholders take intervention measures such as reintroduction of selected species and restocking of wild populations in the urban forest patches to regenerate the forest ecosystems.
Synthesis and evaluation of chalcone analogues based pyrimidines as angiotensin converting enzyme inhibitors

Bukhari SN, Butt AM, Amjad MW, Ahmad W, Shah VH, Trivedi AR

Pak J Biol Sci, 2013 Nov 01;16(21):1368-72.
PMID: 24511749

Hypertension is a widespread and frequently progressive ailment that imparts a foremost threat for cardiovascular and renal disorders. Mammoth efforts are needed for the synthesis of innovative antihypertensive agents to combat this lethal disease. Chalcones have shown antihypertensive activity through inhibition of Angiotensin Converting Enzyme (ACE). Hence, a series of chalcone analogues is synthesized and used as precursor for the synthesis of novel series of pyrimidines. Precursor chalcones were prepared by reacting aldehydes and ketones in presence of sodium hydroxide followed by synthesis of corresponding pyrimidines by reaction with urea in presence of potassium hydroxide. Both groups were then evaluated for their effects on ACE. The results depicted that pyrimidines were more active than chalcones with methoxy (C5 and P5) substitution showing best results to inhibit ACE. Given that chalcone analogues and pyrimidines show a potential as the angiotensin converting enzyme inhibitors.
Fulltext Higher mortality rates for large- and medium-sized mammals on plantation roads compared to highways in Peninsular Malaysia

Jamhuri J, Edinoor MA, Kamarudin N, Lechner AM, Ashton-Butt A, Azhar B

Ecol Evol, 2020 Nov;10(21):12049-12058.
PMID: 33209269 DOI: 10.1002/ece3.6827

The fragmentation of forests by agricultural expansion, urbanization, and road networks is an ongoing global biodiversity crisis. In Southeast Asia and other tropical regions, wildlife populations are being isolated into pockets of natural habitat surrounded by road networks and monoculture plantations. Mortality from wildlife-vehicle collisions (WVCs) is contributing to a decline in many species of conservation priority in human-modified landscapes. This study is the first in Malaysia to investigate factors affecting the occurrence of WVCs. We assessed roadkill data gathered by the Department of Wildlife and National Parks on small-, medium-, and large-sized mammals in Peninsular Malaysia. We examined the relationship between wildlife road accidents and several environmental factors. We found a total of 605 roadkill animals, involving 21 species, which included three species classified as Endangered. Road type (plantation road or highway), year, and distance of the road from continuous and fragmented forests were significant in determining mammal mortality. Unexpectedly, the majority of road mortality occurred on palm oil plantation roads compared to highways. Mortality of small- and medium-sized mammals was greater at locations further from continuous forest than those closer to fragmented forests. Segmentation of continuous forest by roads should be avoided wherever possible to reduce the threat of roads on crossing wildlife.
Fulltext Graphene Oxide-Doped MgO Nanostructures for Highly Efficient Dye Degradation and Bactericidal Action

Ikram M, Inayat T, Haider A, Ul-Hamid A, Haider J, Nabgan W, et al.

Nanoscale Res Lett, 2021 Apr 07;16(1):56.
PMID: 33825981 DOI: 10.1186/s11671-021-03516-z

Various concentrations (0.01, 0.03 and 0.05 wt ratios) of graphene oxide (GO) nanosheets were doped into magnesium oxide (MgO) nanostructures using chemical precipitation technique. The objective was to study the effect of GO dopant concentrations on the catalytic and antibacterial behavior of fixed amount of MgO. XRD technique revealed cubic phase of MgO, while its crystalline nature was confirmed through SAED profiles. Functional groups presence and Mg-O (443 cm-1) in fingerprint region was evident with FTIR spectroscopy. Optical properties were recorded via UV-visible spectroscopy with redshift pointing to a decrease in band gap energy from 5.0 to 4.8 eV upon doping. Electron-hole recombination behavior was examined through photoluminescence (PL) spectroscopy. Raman spectra exhibited D band (1338 cm-1) and G band (1598 cm-1) evident to GO doping. Formation of nanostructure with cubic and hexagon morphology was confirmed with TEM, whereas interlayer average d-spacing of 0.23 nm was assessed using HR-TEM. Dopants existence and evaluation of elemental constitution Mg, O were corroborated using EDS technique. Catalytic activity against methyl blue ciprofloxacin (MBCF) was significantly reduced (45%) for higher GO dopant concentration (0.05), whereas bactericidal activity of MgO against E. coli was improved significantly (4.85 mm inhibition zone) upon doping with higher concentration (0.05) of GO, owing to the formation of nanorods.
2-Aminothiazole-Oxadiazole Bearing N-Arylated Butanamides: Convergent Synthesis, Tyrosinase Inhibition, Kinetics, Structure-Activity Relationship, and Binding Conformations

Raza H, Rehman Sadiq Butt A, Athar Abbasi M, Aziz-Ur-Rehman, Zahra Siddiqui S, Hassan M, et al.

Chem Biodivers, 2023 Feb;20(2):e202201019.
PMID: 36597268 DOI: 10.1002/cbdv.202201019

A multi-step synthesis of novel bi-heterocyclic N-arylated butanamides was consummated through a convergent strategy and the structures of these medicinal scaffolds, 7a-h, were corroborated using spectral techniques. The in vitro analysis of these hybrid molecules revealed their potent tyrosinase inhibition as compared to the standard used. The kinetics mechanism was investigated through Lineweaver-Burk plots which exposed that, 7f, inhibited tyrosinase enzyme non-competitively by forming the enzyme-inhibitor complex. The inhibition constants Ki calculated from Dixon plots for this compound was 0.025 μM. Their binding conformations were ascertained by in silico computational studies whereby these molecules disclosed good binding energy values (kcal/mol). So, it was anticipated from the current research that these bi-heterocyclic butanamides might be probed as imperative therapeutic agents for melanogenesis.
Fulltext Predation of potential insect pests in oil palm plantations, rubber tree plantations, and fruit orchards

Denan N, Wan Zaki WM, Norhisham AR, Sanusi R, Nasir DM, Nobilly F, et al.

Ecol Evol, 2020 Jan;10(2):654-661.
PMID: 32015833 DOI: 10.1002/ece3.5856

In human-modified landscapes, important ecological functions such as predation are negatively affected by anthropogenic activities, including the use of pesticides and habitat degradation. Predation of insect pests is an indicator of healthy ecosystem functioning, which provides important ecosystem services, especially for agricultural systems. In this study, we compare predation attempts from arthropods, mammals, and birds on artificial caterpillars in the understory, between three tropical agricultural land-use types: oil palm plantations, rubber tree plantations, and fruit orchards. We collected a range of local and landscape-scale data including undergrowth vegetation structure; elevation; proximity to forest; and canopy cover in order to understand how environmental variables can affect predation. In all three land-use types, our results showed that arthropods and mammals were important predators of artificial caterpillars and there was little predation by birds. We did not find any effect of the environmental variables on predation. There was an interactive effect between land-use type and predator type. Predation by mammals was considerably higher in fruit orchards and rubber tree than in oil palm plantations, likely due to their ability to support higher abundances of insectivorous mammals. In order to maintain or enhance natural pest control in these common tropical agricultural land-use types, management practices that benefit insectivorous animals should be introduced, such as the reduction of pesticides, improvement of understory vegetation, and local and landscape heterogeneity.
Fulltext Synthesis and exploration of a novel chlorobenzylated 2-aminothiazole-phenyltriazole hybrid as migratory inhibitor of B16F10 in melanoma cells

Athar Abbasi M, Yu SM, Aziz-Ur-Rehman, Siddiqui SZ, Kim SJ, Raza H, et al.

Toxicol Rep, 2019;6:897-903.
PMID: 31516842 DOI: 10.1016/j.toxrep.2019.08.016

In the study presented here, a novel chlorobenzylated bi-heterocyclic hybrid molecule (7) was synthesized and its structural confirmation was carried out by IR, 1H-NMR, 13C-NMR and CHN analysis data. This compound 7 was subjected to biological study with B16F10 mouse melanoma cells. The anti-proliferative results showed that 7 showed no significant toxicity at concentrations ranging of 0-44 μM. The treatment of B16F10 cells with 7 at aforementioned concentration range indicated that migration of cells was significantly lower than that of the control cells in a dose dependent manner. The possible migration inhibitory effect of these melanoma cells was further evaluated through gelatinolytic activity of MMP-2 and MMP-9 secreted from B16F10 cells. It was inferred from our results that 7 was not affecting the expression and activity of these enzymes. Some other zinc-dependent matrix metalloproteinases (MMPs) were involved in the inhibitory progression. Taken together, compound 7 inhibited migrations of B16F10 mouse melanoma cells. Therefore, it may deserve consideration as a potential agent for the treatment of cancer.
Liver failure determines the outcome in patients of acute-on-chronic liver failure (ACLF): comparison of APASL ACLF research consortium (AARC) and CLIF-SOFA models

Choudhury A, Jindal A, Maiwall R, Sharma MK, Sharma BC, Pamecha V, et al.

Hepatol Int, 2017 Sep;11(5):461-471.
PMID: 28856540 DOI: 10.1007/s12072-017-9816-z

BACKGROUND AND AIMS: Acute-on-chronic liver failure (ACLF) is a progressive disease associated with rapid clinical worsening and high mortality. Early prediction of mortality and intervention can improve patient outcomes. We aimed to develop a dynamic prognostic model and compare it with the existing models.
METHODS: A total of 1402 ACLF patients, enrolled in the APASL-ACLF Research Consortium (AARC) with 90-day follow-up, were analyzed. An ACLF score was developed in a derivation cohort (n = 480) and was validated (n = 922).
RESULTS: The overall survival of ACLF patients at 28 days was 51.7%, with a median of 26.3 days. Five baseline variables, total bilirubin, creatinine, serum lactate, INR and hepatic encephalopathy, were found to be independent predictors of mortality, with AUROC in derivation and validation cohorts being 0.80 and 0.78, respectively. AARC-ACLF score (range 5-15) was found to be superior to MELD and CLIF SOFA scores in predicting mortality with an AUROC of 0.80. The point scores were categorized into grades of liver failure (Gr I: 5-7; II: 8-10; and III: 11-15 points) with 28-day cumulative mortalities of 12.7, 44.5 and 85.9%, respectively. The mortality risk could be dynamically calculated as, with each unit increase in AARC-ACLF score above 10, the risk increased by 20%. A score of ≥11 at baseline or persisting in the first week was often seen among nonsurvivors (p = 0.001).
CONCLUSIONS: The AARC-ACLF score is easy to use, dynamic and reliable, and superior to the existing prediction models. It can reliably predict the need for interventions, such as liver transplant, within the first week.
Fulltext Global Impact of COVID-19 on Stroke Care and IV Thrombolysis

Nogueira RG, Qureshi MM, Abdalkader M, Martins SO, Yamagami H, Qiu Z, et al.

Neurology, 2021 Jun 08;96(23):e2824-e2838.
PMID: 33766997 DOI: 10.1212/WNL.0000000000011885

OBJECTIVE: To measure the global impact of COVID-19 pandemic on volumes of IV thrombolysis (IVT), IVT transfers, and stroke hospitalizations over 4 months at the height of the pandemic (March 1 to June 30, 2020) compared with 2 control 4-month periods.
METHODS: We conducted a cross-sectional, observational, retrospective study across 6 continents, 70 countries, and 457 stroke centers. Diagnoses were identified by their ICD-10 codes or classifications in stroke databases.
RESULTS: There were 91,373 stroke admissions in the 4 months immediately before compared to 80,894 admissions during the pandemic months, representing an 11.5% (95% confidence interval [CI] -11.7 to -11.3, p < 0.0001) decline. There were 13,334 IVT therapies in the 4 months preceding compared to 11,570 procedures during the pandemic, representing a 13.2% (95% CI -13.8 to -12.7, p < 0.0001) drop. Interfacility IVT transfers decreased from 1,337 to 1,178, or an 11.9% decrease (95% CI -13.7 to -10.3, p = 0.001). Recovery of stroke hospitalization volume (9.5%, 95% CI 9.2-9.8, p < 0.0001) was noted over the 2 later (May, June) vs the 2 earlier (March, April) pandemic months. There was a 1.48% stroke rate across 119,967 COVID-19 hospitalizations. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection was noted in 3.3% (1,722/52,026) of all stroke admissions.
CONCLUSIONS: The COVID-19 pandemic was associated with a global decline in the volume of stroke hospitalizations, IVT, and interfacility IVT transfers. Primary stroke centers and centers with higher COVID-19 inpatient volumes experienced steeper declines. Recovery of stroke hospitalization was noted in the later pandemic months.

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