Systematic challenges and opportunities in insect monitoring: a Global South perspective

Insect monitoring is pivotal for assessing biodiversity and informing conservation strategies. This study delves into the complex realm of insect monitoring in the Global South-world developing and least-developed countries as identified by the United Nations Conference on Trade and Development-highlighting challenges and proposing strategic solutions. An analysis of publications from 1990 to 2024 reveals an imbalance in research contributions between the Global North and South, highlighting disparities in entomological research and the scarcity of taxonomic expertise in the Global South. We discuss the socio-economic factors that exacerbate the issues, including funding disparities, challenges in collaboration, infrastructure deficits, information technology obstacles and the impact of local currency devaluation. In addition, we emphasize the crucial role of environmental factors in shaping insect diversity, particularly in tropical regions facing multiple challenges including climate change, urbanization, pollution and various anthropogenic activities. We also stress the need for entomologists to advocate for ecosystem services provided by insects in addressing environmental issues. To enhance monitoring capacity, we propose strategies such as community engagement, outreach programmes and cultural activities to instill biodiversity appreciation. Further, language inclusivity and social media use are emphasized for effective communication. More collaborations with Global North counterparts, particularly in areas of molecular biology and remote sensing, are suggested for technological advancements. In conclusion, advocating for these strategies-global collaborations, a diverse entomological community and the integration of transverse disciplines-aims to address challenges and foster inclusive, sustainable insect monitoring in the Global South, contributing significantly to biodiversity conservation and overall ecosystem health. This article is part of the theme issue 'Towards a toolkit for global insect biodiversity monitoring'.

Occurrence and characteristics of microdebris in commercial fish species of Guyana, South America

Microdebris ingestion in fish is widespread and has adverse effects on marine life. This study assessed the occurrence and type of microdebris found in three commercially important fish species from different landing sites along Guyana's coast. Visual examination of fish gut content was initially carried out using the naked eye and a hand lens. Microscopic examinations were subsequently carried out to determine the number and type of debris present. Forty percent of the fishes examined had microdebris present in their bodies. A total of 112 microdebris particles were collected from 90 specimens of three species (Bagre bagre, Nebris microps, Macrodon ancyclodon). The microdebris particles observed included pellets, microbeads, fragments, fiber (wool), films, and foams. White-colored materials were the most frequently ingested. Most of the collected materials were large microdebris (>1 to 5 mm) that resembled pellets and microbeads. This study displayed the prevalence of microdebris ingestion by commercial fish in Guyana.

Detecting gold mining impacts on insect biodiversity in a tropical mining frontier with SmallSat imagery

Gold mining is a major driver of Amazonian forest loss and degradation. As mining activity encroaches on primary forest in remote and inaccessible areas, satellite imagery provides crucial data for monitoring mining-related deforestation. High-resolution imagery, in particular, has shown promise for detecting artisanal gold mining at the forest frontier. An important next step will be to establish relationships between satellite-derived land cover change and biodiversity impacts of gold mining. In this study, we set out to detect artisanal gold mining using high-resolution imagery and relate mining land cover to insects, a taxonomic group that accounts for the majority of faunal biodiversity in tropical forests. We applied an object-based image analysis (OBIA) to classify mined areas in an Indigenous territory in Guyana, using PlanetScope imagery with ~3.7 m resolution. We complemented our OBIA with field surveys of insect family presence or absence in field plots (n = 105) that captured a wide range of mining disturbances. Our OBIA was able to identify mined objects with high accuracy (>90% balanced accuracy). Field plots with a higher proportion of OBIA-derived mine cover had significantly lower insect family richness. The effects of mine cover on individual insect taxa were highly variable. Insect groups that respond strongly to mining disturbance could potentially serve as bioindicators for monitoring ecosystem health during and after gold mining. With the advent of global partnerships that provide universal access to PlanetScope imagery for tropical forest monitoring, our approach represents a low-cost and rapid way to assess the biodiversity impacts of gold mining in remote landscapes.

Biological control of mosquitoes with odonates: A case study in Guyana

Abstract. Dasrat CM, Maharaj G. 2021. Biological control of mosquitoes with odonates: A case study in Guyana. Nusantara Bioscience 13: 163-170. Mosquitoes have plagued the lives of tropical residents as pests. However, due to their role as vectors of life-threatening diseases, controlling their population is necessary, especially in areas of prevalence – the Caribbean and Equatorial regions. In Guyana, we employ chemical treatments sub-regionally to eradicate mosquitoes. However, this treatment has limited success and is harmful to the environment. Therefore, our study focused on an environmentally friendly method such as biological control. This study was conducted at the University of Guyana, Turkeyen campus, where we exploited Odonata; Anisoptera, and Zygoptera as natural predators of mosquitoes of the genus Culex. The feeding efficiency and behaviors of naiads from the families of Libellulidae and Coenagrionidae were assessed during April – May of 2018. Each naiad was fed three Culine pupae and larvae, then observed for 60 minutes. We found that both groups pursue soft-bodied larvae and Libellulidae naiads are more efficient predators due to the higher feeding rate than Coenagrionidae. This finding is related to a behavioral study where we observed Libellulidae as active hunters that masticate and consume faster than Coenagrionidae, which are lay and wait, opportunistic predators that swallow their prey. We concluded that Libellulidae is an efficient predator for mosquito larvae of the Culex genus, and we found that there is a link between morphologic characteristics and feeding behaviors. We hope to use these results as a baseline study to develop mosquito biological control in Guyana. These can be used to reduce mosquito populations and the occurrence of vector diseases as well as improve integrated pest and vector management.

697 An Evaluation of Patient Outcomes Following Percutaneous Cholecystostomy (PC) For Acute Cholecystitis (AC) At Our Health Board Between 2011-2020

Introduction

PC is a radiological intervention used in the management of high-risk patients with AC.

Method

A retrospective study of outcomes following PC, including success rates, complications, AC resolution, readmissions, and subsequent cholecystectomy.

Results

Our database identified 28 patients (14M:14F), median age 73 (range 40-93). 82% were ASA III/IV. Median follow-up was 2 (range 0-8) years. Imaging suggested AC in 61% and empyema in 39%. 86% were calculous. All procedures were USS-guided with 100% success. AC resolution occurred in 89.3%. Of three unresolved, there was 1 death day-1 post-PC (non-procedure related), 1 index cholecystectomy, 1 chronic complicated cholecystitis. 28.6% developed complications, 2 major (1 late biliary peritonitis and 1 cholecystocutaneous fistula with abdominal wall abscess), 17.9% dislodged drain, 10.7% other. 20 patients had bile cultures (70% positive, mainly gram-negative). 17.9% patients were readmitted with AC, 1 had repeat PC. 21.4% had subsequent ERCP. 32.1% underwent subsequent cholecystectomy, 1 laparoscopic cholecystectomy(LC) index, 4 elective (3 LC, 1 open), 4 emergency (2 LC, 1 LC subtotal, 1 failed open with drain insertion).

Conclusions

PC is both safe and effective with significant procedural success rates and resolution rates. There are few major complications but significant morbidities, mainly dislodged drains. One-third of patients have subsequent cholecystectomy.

Population-based cohort study of variation in the use of emergency cholecystectomy for benign gallbladder diseases

Background

The aims of this prospective population-based cohort study were to identify the patient and hospital characteristics associated with emergency cholecystectomy, and the influences of these in determining variations between hospitals.

Methods

Data were collected for consecutive patients undergoing cholecystectomy in acute UK and Irish hospitals between 1 March and 1 May 2014. Potential explanatory variables influencing the performance of emergency cholecystectomy were analysed by means of multilevel, multivariable logistic regression modelling using a two-level hierarchical structure with patients (level 1) nested within hospitals (level 2).

Results

Data were collected on 4744 cholecystectomies from 165 hospitals. Increasing age, lower ASA fitness grade, biliary colic, the need for further imaging (magnetic retrograde cholangiopancreatography), endoscopic interventions (endoscopic retrograde cholangiopancreatography) and admission to a non-biliary centre significantly reduced the likelihood of an emergency cholecystectomy being performed. The multilevel model was used to calculate the probability of receiving an emergency cholecystectomy for a woman aged 40 years or over with an ASA grade of I or II and a BMI of at least 25·0 kg/m2, who presented with acute cholecystitis with an ultrasound scan showing a thick-walled gallbladder and a normal common bile duct. The mean predicted probability of receiving an emergency cholecystectomy was 0·52 (95 per cent c.i. 0·45 to 0·57). The predicted probabilities ranged from 0·02 to 0·95 across the 165 hospitals, demonstrating significant variation between hospitals.

Conclusion

Patients with similar characteristics presenting to different hospitals with acute gallbladder pathology do not receive comparable care.

Mobility of the spin-labeled side chains of some novel antifolate inhibitors in their complexes with dihydrofolate reductase

Four spin-labeled inhibitors of dihydrofolate reductase (DHFR) have been synthesized, each of which has the 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) reporting group at a different distance from the 2,4-diaminopyrimidine moiety by which the inhibitors are anchored and oriented in the active site. Inhibitors in which the TEMPO group is attached by a short side chain are weakly bound to DHFR from bacteria (Streptococcus faecium and Lactobacillus casei), to the bovine enzyme and to recombinant human DHFR. However, binding is sufficiently tight, especially in the ternary complexes with NADPH, for recording of the EPR spectra of the bound ligands. The spectra indicate that when these inhibitors are bound to the enzyme the TEMPO group is highly immobilized with correlation time, tau c, 4-20ns. Inhibitors that have the reporter group attached to the glutamate moiety of methotrexate bind to all four DHFRs more tightly than the inhibitors with shorter side chains by factors of up to 10(6). However, in most complexes formed by the inhibitors with longer side chains immobilization of the TEMPO group is slight (tau c 0.2-4 ns). These results are in general agreement with predictions from X-ray crystallographic results including thermal factors but there are some unanticipated differences between some results for bacterial and eukaryotic enzymes. Three of the splin-labeled inhibitors would provide good probes for distance measurements in and around the active site of mammalian DHFR.

Dissociation constants for dihydrofolic acid and dihydrobiopterin and implications for mechanistic models for dihydrofolate reductase

The dissociation constants (pKa) for the pteridine ring system of dihydrofolate (H2folate) have been redetermined, and those for dihydrobiopterin (H2biopterin) have been determined. Determination of the pKa for N5 of H2folate is complicated by the low solubility and instability of H2folate at pH 2-4, and other complicating factors. The initial rate of absorbance change due to degradation is a maximum at pH 2.5, and the products depend on the oxygen concentration: under aerobic conditions, (p-aminobenzoyl)glutamic acid and 7,8-dihydropterin-6-carboxaldehyde are major products. H2Biopterin is much more soluble and more stable at low pH. For protonation of N5, the pKa is 2.56 +/- 0.01 for H2biopterin and 2.59 +/- 0.03 for H2folic acid. Spectrophotometric determination of the pKa for the N3-O4 amide group of H2folate is subject to serious errors when a wavelength between 220 and 235 nm is used. These errors arise from the pH-dependent absorbance of mercaptoethanol often present in the preparation. The amide group has a pKa of 10.41 +/- 0.04 in H2biopterin and 10.85 +/- 0.04 in H2folate. The redetermined value for the pKa of N5 of H2folate has implications for mechanistic models for dihydrofolate reductase, and revised kinetic constants have been calculated for one model.