p53 protein expression patterns associated with TP53 mutations in breast carcinoma.

PURPOSE: The importance of a TP53 mutation has been demonstrated in several tumor types, including breast cancer (BC). However, the accuracy of p53 protein expression as a predictor of gene mutation has not been well studied in BC. Therefore, we evaluated p53 protein expression associated with TP53 mutations in breast cancers from 64 patients. METHODS: TP53 mutation was examined using next-generation sequencing (NGS). p53 protein expression was examined using immunohistochemistry (IHC). RESULTS: Among the 64 BCs, 55% demonstrated abnormal expression patterns including 27% overexpression, 22% null, 6% equivocal with 45% having a wild-type pattern. A TP53 mutation was present in 53% (34/64) of tumors including 30% (19/64) demonstrating a missense mutation, 11% (7/64) with a frameshift mutation, 11% (7/64) with a nonsense mutation, and 3% (1/64) with a splice site mutation. Abnormal expression of p53 protein was present in 33 of 34 (97%) tumors carrying a TP53 mutation; conversely, a wild-type pattern was present in 28 of 30 (93%) tumors without a detectable mutation (p < 0.0001). The majority of BCs with a p53 IHC overexpression pattern (15/17, 88%) contained a missense TP53 mutation; while the majority of BCs with a null pattern (12/14, 86%) contained a truncating mutation (p < 0.0001). The BCs with a null pattern are associated with a high Nottingham histological grade and a triple-negative phenotype when compared to those demonstrating overexpression (p < 0.05). CONCLUSION: These findings suggest that p53 IHC can be a potential surrogate for TP53 mutations in BC. Different p53 expression patterns may correlate with specific TP53 genetic mutations in BC.

Chemical Probes to Interrogate the Extreme Environment of Mosquito Larval Guts.

Mosquito control methods are vital to curtail the spread of life-threatening illnesses, such as dengue fever, malaria, and yellow fever. Vector control technologies must be selective to minimize deleterious effects on our ecosystem. Successful methods that control mosquito larva populations utilize the uniquely high alkaline nature of the midgut. Here, we present novel protected triazabutadienes (pTBD) that are deprotected under basic conditions of the larval midgut, releasing an aryl diazonium ion (ADI) that results in protein modification. The probes contain a bioorthogonal terminal alkyne handle, enabling a selective Cu-click reaction with an azidofluorophore for quantification by SDS PAGE and visualization using fluorescence microscopy. A control TBD, unable to release an ADI, did not label the midgut. We envision our chemical probes will aid in the development of new selective mosquito control methods, thus preventing the spread of mosquito-borne illnesses with minimal impact on other organisms in the ecosystem.

Trajectories and tipping points of piñon-juniper woodlands after fire and thinning.

Piñon-juniper (PJ) woodlands are a dominant community type across the Intermountain West, comprising over a million acres and experiencing critical effects from increasing wildfire. Large PJ mortality and regeneration failure after catastrophic wildfire have elevated concerns about the long-term viability of PJ woodlands. Thinning is increasingly used to safeguard forests from fire and in an attempt to increase climate resilience. We have only a limited understanding of how fire and thinning will affect the structure and function of PJ ecosystems. Here, we examined vegetation structure, microclimate conditions, and PJ regeneration dynamics following ~20 years post-fire and thinning treatments. We found that burned areas had undergone a state shift that did not show signs of returning to their previous state. This shift was characterized by (1) distinct plant community composition dominated by grasses; (2) a lack of PJ recruitment; (3) a decrease in the sizes of interspaces in between plants; (4) lower abundance of late successional biological soil crusts; (5) lower mean and minimum daily soil moisture values; (6) lower minimum daily vapor pressure deficit; and (7) higher photosynthetically active radiation. Thinning created distinct plant communities and served as an intermediate between intact and burned communities. More intensive thinning decreased PJ recruitment and late successional biocrust cover. Our results indicate that fire has the potential to create drier and more stressful microsite conditions, and that, in the absence of active management following fire, there may be shifts to persistent ecological states dominated by grasses. Additionally, more intensive thinning had a larger impact on community structure and recruitment than less intensive thinning, suggesting that careful consideration of goals could help avoid unintended consequences. While our results indicate the vulnerability of PJ ecosystems to fire, they also highlight management actions that could be adapted to create conditions that promote PJ re-establishment.

Characterization of essential eggshell proteins from Aedes aegypti mosquitoes.

BACKGROUND: Up to 40% of the world population live in areas where mosquitoes capable of transmitting the dengue virus, including Aedes aegypti, coexist with humans. Understanding how mosquito egg development and oviposition are regulated at the molecular level may provide new insights into novel mosquito control strategies. Previously, we identified a protein named eggshell organizing factor 1 (EOF1) that when knocked down with RNA interference (RNAi) resulted in non-melanized and fragile eggs that did not contain viable embryos. RESULTS: In this current study, we performed a comprehensive RNAi screen of putative A. aegypti eggshell proteins to identify additional proteins that interact with intracellular EOF1. We identified several proteins essential for eggshell formation in A. aegypti and characterized their phenotypes through a combination of molecular and biochemical approaches. We found that Nasrat, Closca, and Polehole structural proteins, together with the Nudel serine protease, are indispensable for eggshell melanization and egg viability. While all four proteins are predominantly expressed in ovaries of adult females, Nudel messenger RNA (mRNA) expression is highly upregulated in response to blood feeding. Furthermore, we identified four additional secreted eggshell enzymes that regulated mosquito eggshell formation and melanization. These enzymes included three dopachrome-converting enzymes (DCEs) and one cysteine protease. All eight of these eggshell proteins were essential for proper eggshell formation. Interestingly, their eggshell surface topologies in response to RNAi did not phenocopy the effect of RNAi-EOF1, suggesting that additional mechanisms may influence how EOF1 regulates eggshell formation and melanization. CONCLUSIONS: While our studies did not identify a definitive regulator of EOF1, we did identify eight additional proteins involved in mosquito eggshell formation that may be leveraged for future control strategies.

Mutations in Homologous Recombination Genes and Loss of Heterozygosity Status in Advanced-Stage Breast Carcinoma.

Poly (adenosine diphosphate-ribose) polymerase inhibitors (PARPis) have demonstrated antitumor activity in cancers with a homologous recombination deficiency (HRD) and have recently been approved by the FDA for the treatment of germline BRCA1/2-mutation-associated breast cancer. PARPis have also been found to be efficacious in BRCA wild-type (BRCAwt) lesions with high genomic loss of heterozygosity (LOH-high). The goal of this study was to retrospectively investigate the tumor mutations in homologous recombination (HRR) genes and the LOH score in advanced-stage breast carcinomas (BCs). Sixty-three patients were included in our study, 25% of whom had HRR gene mutations in their tumors, including 6% BRCA1/2 and 19% non-BRCA-containing gene mutations. An HRR gene mutation was associated with a triple-negative phenotype. Twenty-eight percent of the patients had an LOH-high score, which, in turn, was associated with a high histological grade, a triple-negative phenotype, and a high tumor mutational burden (TMB). Among the six patients who received PARPi therapy, one had a tumor with a PALB2 mutation other than BRCA and had a clinical partial response. Twenty-two percent of the LOH-low tumors had BRCAwt-HRR gene mutations, compared with 11% of the LOH-high tumors. Comprehensive genomic profiling revealed a subset of breast cancer patients with a BRCAwt-HRR gene mutation that would be missed by an LOH test. The necessity of next-generation sequencing coupled with HRR gene analysis for PARPi therapy requires further investigation in clinical trials.

Chemical probes to interrogate the extreme environment of mosquito larval guts.

Mosquito control methods are vital for the spread of life-threatening illnesses such as dengue fever, malaria, and yellow fever. Vector control technologies must be selective to minimize deleterious effects to our ecosystem. Successful methods that control mosquito larva populations utilize the uniquely high alkaline nature of the midgut. Here, we present novel protected triazabutadienes (pTBD) which are deprotected under basic conditions of the larval midgut, releasing an aryl diazonium ion (ADI) that results in protein modification. The probes contain a bioorthogonal terminal alkyne handle, enabling a selective Cu-click reaction with an azido-fluorophore for quantification by SDS PAGE and visualization using fluorescence microscopy. A control TBD, unable to release an ADI, did not label the midgut. We envision our chemical probes will aid in the development of new selective mosquito control methods thus preventing the spread of mosquito-borne illnesses with minimal impact on other organisms in the ecosystem.

Ultraviolet dosage and decontamination efficacy were widely variable across 14 UV devices after testing a dried enveloped ribonucleic acid virus surrogate for SARS-CoV-2.

Aims: The dosages and efficacy of 14 ultraviolet (UV) decontamination technologies were measured against a SARS-CoV-2 surrogate virus that was dried onto different materials for laboratory and field testing. Methods and results: A live enveloped, ribonucleic acid (RNA) virus surrogate for SARS-CoV-2 was dried on stainless steel 304 (SS304), Navy Top Coat-painted SS304 (NTC), cardboard, polyurethane, polymethyl methacrylate (PMMA), and acrylonitrile butadiene styrene (ABS) materials at > 8.0 log10 plaque-forming units (PFU) per test coupon. The coupons were then exposed to UV radiation during both laboratory and field testing. Commercial and prototype UV-emitting devices were measured for efficacy: four handheld devices, three room/surface-disinfecting machines, five air disinfection devices, and two larger custom-made machines. UV device dosages ranged from 0.01 to 729 mJ cm-2. The antiviral efficacy among the different UV devices ranged from no decontamination up to nearly achieving sterilization. Importantly, cardboard required far greater dosage than SS304. Conclusion: Enormous variability in dosage and efficacy was measured among the different UV devices. Porous materials limit the utility of UV decontamination. Significance and impact of the study: UV devices have wide variability in dosages, efficacy, hazards, and UV output over time, indicating that each UV device needs independent technical measurement and assessment for product development prior to and during use.

The consequences of climate change for dryland biogeochemistry.

Drylands, which cover > 40% of Earth's terrestrial surface, are dominant drivers of global biogeochemical cycling and home to more than one third of the global human population. Climate projections predict warming, drought frequency and severity, and evaporative demand will increase in drylands at faster rates than global means. As a consequence of extreme temperatures and high biological dependency on limited water availability, drylands are predicted to be exceptionally sensitive to climate change and, indeed, significant climate impacts are already being observed. However, our understanding and ability to forecast climate change effects on dryland biogeochemistry and ecosystem functions lag behind many mesic systems. To improve our capacity to forecast ecosystem change, we propose focusing on the controls and consequences of two key characteristics affecting dryland biogeochemistry: (1) high spatial and temporal heterogeneity in environmental conditions and (2) generalized resource scarcity. In addition to climate change, drylands are experiencing accelerating land-use change. Building our understanding of dryland biogeochemistry in both intact and disturbed systems will better equip us to address the interacting effects of climate change and landscape degradation. Responding to these challenges will require a diverse, globally distributed and interdisciplinary community of dryland experts united towards better understanding these vast and important ecosystems.

Ultraviolet Dosage and Decontamination Efficacy was Widely Variable Across 14 UV Devices after Testing a Dried Enveloped Ribonucleic Acid Virus Surrogate for SARS-CoV-2

AbstractO_ST_ABSAimsC_ST_ABSThe dosages and efficacy of 14 ultraviolet (UV) decontamination technologies were measured against a SARS-CoV-2 surrogate virus that was dried on to different materials for lab and field testing. Methods and ResultsA live enveloped, ribonucleic acid (RNA) virus surrogate for SARS- CoV-2 was dried on stainless steel 304 (SS304), Navy Top Coat-painted SS304 (NTC), cardboard, polyurethane, polymethyl methacrylate (PMMA), and acrylonitrile butadiene styrene (ABS) at > 8.0 log10 plaque-forming units (PFU) per test coupon. The coupons were then exposed to UV radiation during both lab and field testing. Commercial and prototype UV- emitting devices were measured for efficacy: 4 handheld devices, 3 room/surface-disinfecting machines, 5 air-disinfection devices, and 2 larger custom-made machines. UV device dosages ranged from 0.01-729 mJ cm-2. Anti-viral efficacy among the different UV devices ranged from no decontamination up to nearly achieving sterilization. Importantly, cardboard required far more dosage than SS304. ConclusionsEnormous variability in dosage and efficacy was measured among the different UV devices. Porous materials limit the utility of UV decontamination. Significance and Impact of the StudyUV devices have wide variability in dosages, efficacy, hazards, and UV output over time indicating that each UV device needs independent technical measurement and assessment for product development, prior to, and during use.

Aedes species (Diptera: Culicidae) ecological and host feeding patterns in the north-eastern parts of South Africa, 2014-2018.

BACKGROUND: There is a paucity of recent data and knowledge on mosquito diversity and potential vectors of arboviruses in South Africa, with most of the available data dating back to the 1950s-1970s. Aedes and Culex species are the major vectors of some of the principal arboviruses which have emerged and re-emerged in the past few decades. METHODS: In this study we used entomological surveillance in selected areas in the north-eastern parts of South Africa from 2014 to 2018 to assess mosquito diversity, with special emphasis on the Aedes species. The impact of trap types and environmental conditions was also investigated. Identification of the blood meal sources of engorged females collected during the study period was carried out, and DNA barcodes were generated for selected species. RESULTS: Overall, 18.5% of the total Culicidae mosquitoes collected belonged to the genus Aedes, with 14 species recognised or suspected vectors of arboviruses. Species belonging to the Neomelaniconion subgenus were commonly collected in the Bushveld savanna at conservation areas, especially Aedes mcintoshi and Aedes circumluteolus. Aedes aegypti was present in all sites, albeit in low numbers. Temperature was a limiting factor for the Aedes population, and they were almost exclusively collected at temperatures between 18 °C and 27 °C. The cytochrome oxidase subunit I (COI) barcode fragment was amplified for 21 Aedes species, and for nine of these species it was the first sequence information uploaded on GenBank. CONCLUSION: This study provides a better understanding of the diversity and relative abundance of Aedes species in the north-east of South Africa. The information provided here will contribute to future arboviral research and implementation of efficient vector control and prevention strategies.

Muted responses to chronic experimental nitrogen deposition on the Colorado Plateau.

Anthropogenic nitrogen (N) deposition is significantly altering both community structure and ecosystem processes in terrestrial ecosystems across the globe. However, our understanding of the consequences of N deposition in dryland systems remains relatively poor, despite evidence that drylands may be particularly vulnerable to increasing N inputs. In this study, we investigated the influence of 7 years of multiple levels of simulated N deposition (0, 2, 5, and 8 kg N ha-1 year-1) on plant community structure and biological soil crust (biocrust) cover at three semi-arid grassland sites spanning a soil texture gradient. Biocrusts are a surface community of mosses, lichens, cyanobacteria, and/or algae, and have been shown to be sensitive to N inputs. We hypothesized that N additions would decrease plant diversity, increase abundance of the invasive annual grass Bromus tectorum, and decrease biocrust cover. Contrary to our expectations, we found that N additions did not affect plant diversity or B. tectorum abundance. In partial support of our hypotheses, N additions negatively affected biocrust cover in some years, perhaps driven in part by inter-annual differences in precipitation. Soil inorganic N concentrations showed rapid but ephemeral responses to N additions and plant foliar N concentrations showed no response, indicating that the magnitude of plant and biocrust responses to N fertilization may be buffered by endogenous N cycling. More work is needed to determine N critical load thresholds for plant community and biocrust dynamics in semi-arid systems and the factors that determine the fate of N inputs.

Sentinel Lymph Node Involvement by Epithelial Inclusions Mimicking Metastatic Carcinoma: A Diagnostic Pitfall.

BACKGROUND An epithelial inclusion cyst within a lymph node denotes a heterotopic phenomenon. Nodal epithelial inclusion cysts have been reported in a variety of anatomical locations including pelvic, abdominal, mediastinal, and axillary regions. While nodal melanocytic nevus (also known as nevus cell aggregates) is the most common heterotopic phenomena involving the axillary lymph nodes, the presence of benign epithelial inclusion cysts in axillary lymph nodes is a rare but well-reported finding. Such documentation is in part due to assessment of sentinel lymph nodes in breast cancer becoming standard of care. These epithelial inclusion cysts offer a diagnostic pitfall in evaluation of sentinel lymph node in the setting of breast carcinoma. They also complicate assessment of sentinel lymph node during intraoperative frozen sections analysis. CASE REPORT We report a case of co-existent of benign squamous-type and glandular-type epithelial inclusions cysts in 2 sentinel lymph nodes in a patient with grade III invasive ductal carcinoma involving the left breast. There have been at least 4 cases reported in literature in which benign epithelial inclusion cysts in sentinel lymph nodes were first mistakenly diagnosed as metastatic carcinoma both during intraoperative frozen section analysis and during review of permanent sections. The missed diagnosis could potentially occur intraoperatively during frozen section sentinel lymph node analysis secondarily due to lack of availability of the primary tumor for comparison and inability to use immunohistochemical stains. CONCLUSIONS Pathologists should be aware of this pitfall especially in frozen section analysis of sentinel lymph node to avoid misdiagnosis and its associated potential grave consequences.

Hot, Humid Air Decontamination of Aircraft Confirmed That High Temperature and High Humidity Are Critical for Inactivation of Infectious, Enveloped Ribonucleic Acid (RNA) Virus.

Aims: To develop infectious (live/dead) enveloped virus test indicators and response surface methodology (RSM) models that evaluate survival of an enveloped ribonucleic acid (RNA) virus on contaminated aircraft materials after exposure to hot, humid air (HHA). Methods and Results: Enveloped RNA bacteriophage Phi6 (Φ6) was dried on wiring insulation, aircraft performance coating (APC), polypropylene, and nylon at ≥ 8 log10 plaque-forming units (PFU) test coupon-1. Only 2.4 log10 inactivation was measured on APC at 70°Celsius (°C), 5% relative humidity (RH) after 24 h. In contrast, HHA RSM models showed a 90% probability of a 7 log10 inactivation at ≥63°C, 90% RH after 1 h, and decontamination kinetics were similar across different materials. HHA decontamination of C-130 and C-17 aircraft showed >7 log10 and ≥5.9 log10 inactivation of enveloped virus on 100 and 110 test indicators, respectively, with a 1-h treatment, excluding ramp-up and ramp-down times. Conclusions: Enveloped RNA virus test indicators were successfully developed, lab tested for HHA decontamination, analyzed for RSM, and field-tested in aircraft demonstrations. Significance and Impact of the Study: The utility of HHA decontamination was demonstrated after inactivating enveloped RNA virus on aircraft with a 1-h HHA treatment within aircraft temperature and RH limits.

Implementing malaria control in South Africa, Eswatini and southern Mozambique during the COVID-19 pandemic.

The COVID-19 pandemic has strained healthcare delivery systems in a number of southern African countries. Despite this, it is imperative that malaria control and elimination activities continue, especially to reduce as far as possible the number and rate of hospitalisations caused by malaria. The implementation of enhanced malaria control/elimination activities in the context of COVID-19 requires measures to protect healthcare workers and the communities they serve. The aim of this review is therefore to present innovative ideas for the timely implementation of malaria control without increasing the risk of COVID-19 to healthcare workers and communities. Specific recommendations for parasite and vector surveillance, diagnosis, case management, mosquito vector control and community outreach and sensitisation are given.

Implementing malaria control in South Africa, Eswatini and southern Mozambique during the COVID-19 pandemic

The COVID-19 global pandemic reached South Africa (SA), Mozambique and Eswatini in March 2020.[1] Since then an exponential increase in SARS-CoV-2 infections has severely stretched SA's healthcare system, especially in terms of in-hospital treatment of severe cases. The impact of COVID-19 in Mozambique and Eswatini at the time of writing has been comparatively mild, but is increasing. It is therefore imperative to reduce as far as possible the number and rate of hospitalisations caused by trauma and other diseases, including malaria. Malaria incidence in SA is seasonal and peaks in the wetter summer months, especially during January to April.[2] Although malaria incidence in SA is currently low, the risk of outbreaks is always present, with the most recent having occurred in 2017 and, at a more localised level in Limpopo Province, in 2019. The reasons for these latest outbreaks are varied and include unusually high rainfall and cross-border movement of migrant populations, fuelling local transmission. These issues are particularly pertinent to COVID-19 in SA's malaria-affected districts. They highlight the importance of mitigating factors contributing to high malaria incidence and consequent hospitalisations, which may be further exacerbated by COVID-19/malaria coinfections and the re-opening of SA's borders with those neighbouring countries with higher malaria transmission intensities.

Robotic-Assisted Total Pericardiectomy for Acute Relapsing Pericarditis: A Case Report.

Acute, relapsing pericarditis is an uncommon potential complication of any cardiothoracic intervention. If medical management fails to mitigate recurrent symptoms, robotic total pericardiectomy can be performed as a definitive therapeutic option. A 33-year-old woman had severely symptomatic, persistent pericarditis, which began 3 weeks after pacemaker placement for tachy-brady syndrome. After failure of pharmacologic treatment, a robot-assisted total pericardiectomy was performed with a drastic improvement in symptoms. Considering that this case of pericarditis was inflammatory (nonconstrictive), a radical excisional approach to all the pericardium was undertaken in order to prevent relapse of symptoms. A bilateral endoscopic off-pump robot-assisted approach was used to completely and fully excise both the anterior and posterior pericardium. In conclusion, we present a case of acute relapsing pericarditis in a very symptomatic patient who failed medical therapy and underwent a robotic totally endoscopic radical pericardiectomy with excellent results. We believe that this technique allows for total pericardiectomy using the least invasive approach and should be considered in the management of this rare but potentially debilitating condition.

First report of Meloidogyne javanica on Ginger and Turmeric in the United States.

Ginger (Zingiber officinale L.) and turmeric (Curcuma longa L.) are two her baceous perennial plant species with rhizomes that are commonly used for flavoring or medicinal purposes. In January 2018, stunting and poorly developed root systems typically associated with plant-parasitic nematode infection were observed on organically grown edible ginger and turmeric in a hoop house in Wheeler County, Georgia. Examination of soil and root samples from symptomatic plants revealed the presence of high populations of root-knot nematodes (Meloidogyne spp.). The second-stage juveniles (J2s) were extracted from soil samples as described by Jenkins (1964). Nematode counts were 285 and 155 J2s per 100 cm3 soil in the areas planted with ginger and turmeric, respectively. Nematode eggs were recovered from infected root systems using the bleach (1%) and blending method (Hussey and Barker, 1973). Examination of the root samples showed the presence of 840 and 320 eggs per g of roots in ginger and turmeric, respectively. Primary diagnosis of the Meloidogyne specimens was done by comparing morphological features observed in the J2s (n = 10) and perineal pattern of females (n = 11) based on the description given by Eisenback and Triantaphyllou (1991) and were tentatively identified as M. javanica (Treub, 1885; Chitwood, 1949). For species identification, DNA sequencing was performed using multiple markers located in 18S ribosomal RNA and 5.8S internal transcribed spacer 1 regions, (18S + ITS) (GenBank Accession No. MK390613), 28S domain 2 and 3 (28S D2/D3) (MK385596), cytochrome oxidase subunit I (COI) (MK391558), and subunit II and 16S (COII + 16S) (MK391557) of mitochondrial DNA following methods as described in Ye et al. (2015). PCR assays by species-specific primers were also conducted to confirm species identity as described by Zijlstra et al. (2000). The blast search results of DNA sequences of 18S + ITS, 28S (D2/D3), COI and COII + 16S revealed the best match as M. javanica, M. incognita (Kofoid and White, 1912; Chitwood, 1949) and M. arenaria (Neal, 1889; Chitwood, 1949) with 99-100% identity. These genes are highly conserved across these three most common root-knot nematode species. However, results of PCR assays by species-specific primers were only positive for M. javanica using primers Fjav/Rjav, but negative for M. incognita by Finc/Rinc and M. arenaria by Far/Rar as described by Zijlstra et al. (2000). Based on morphological characteristics and molecular analyses, the root-knot nematodes infecting ginger and turmeric were identified as M. javanica. After confirmation of the nematode species, a test was conducted in the greenhouse to assess the pathogenicity of the nematode on ginger and turmeric. Five seedlings per plant species (cultivars unknown) were grown in 15 cm-diam plastic pots containing equal parts of pasteurized field soil and sand, and then inoculated with 2,000 eggs of M. javanica. The egg suspension was added into three holes around the base of each seedling. Non-inoculated seedlings (n2 = 25) were used as controls. Plants were arranged in completely randomized design and grown at 25 ± 3 °C for 10 weeks. At the termination of the experiment, small galls were noticed on the roots of the inoculated seedlings of both ginger and turmeric. No galls were observed on the roots of non-inoculated plants. Egg were extracted from the galled roots (Hussey and Barker, 1973) yielding an average of 1040 ± 96 and 732 ± 54 eggs per g of root of ginger and turmeric, respectively. On ginger, the nematode produced large numbers of galls and egg masses on both primary and secondary (feeder) roots, but the galls produced on turmeric were often observed only on primary roots (Fig. 1). No symptoms of root-knot nematode infestation including galls or water-soaked lesions were observed on the outer surface of rhizomes of both ginger and turmeric. However, the size of rhizomes in the M. javanica-infested areas was visibly smaller than that in non-infested areas (Fig. 2). A similar reduction in the growth of turmeric rhizomes was also observed. Meloidogyne incognita has been commonly reported as a nematode pest of ginger (Myers et al., 2017) and turmeric (Hall et al., 2017) in the USA and both M. incognita and M. javanica are known to cause damage on these plant hosts (Ray et al., 1995; Singh and Gupta, 2011). To the best of our knowledge, this is the first report of M. javanica on ginger and turmeric in the USA.Ginger (Zingiber officinale L.) and turmeric (Curcuma longa L.) are two her baceous perennial plant species with rhizomes that are commonly used for flavoring or medicinal purposes. In January 2018, stunting and poorly developed root systems typically associated with plant-parasitic nematode infection were observed on organically grown edible ginger and turmeric in a hoop house in Wheeler County, Georgia. Examination of soil and root samples from symptomatic plants revealed the presence of high populations of root-knot nematodes (Meloidogyne spp.). The second-stage juveniles (J2s) were extracted from soil samples as described by Jenkins (1964). Nematode counts were 285 and 155 J2s per 100 cm3 soil in the areas planted with ginger and turmeric, respectively. Nematode eggs were recovered from infected root systems using the bleach (1%) and blending method (Hussey and Barker, 1973). Examination of the root samples showed the presence of 840 and 320 eggs per g of roots in ginger and turmeric, respectively. Primary diagnosis of the Meloidogyne specimens was done by comparing morphological features observed in the J2s (n = 10) and perineal pattern of females (n = 11) based on the description given by Eisenback and Triantaphyllou (1991) and were tentatively identified as M. javanica (Treub, 1885; Chitwood, 1949). For species identification, DNA sequencing was performed using multiple markers located in 18S ribosomal RNA and 5.8S internal transcribed spacer 1 regions, (18S + ITS) (GenBank Accession No. MK390613), 28S domain 2 and 3 (28S D2/D3) (MK385596), cytochrome oxidase subunit I (COI) (MK391558), and subunit II and 16S (COII + 16S) (MK391557) of mitochondrial DNA following methods as described in Ye et al. (2015). PCR assays by species-specific primers were also conducted to confirm species identity as described by Zijlstra et al. (2000). The blast search results of DNA sequences of 18S + ITS, 28S (D2/D3), COI and COII + 16S revealed the best match as M. javanica, M. incognita (Kofoid and White, 1912; Chitwood, 1949) and M. arenaria (Neal, 1889; Chitwood, 1949) with 99­100% identity. These genes are highly conserved across these three most common root-knot nematode species. However, results of PCR assays by species-specific primers were only positive for M. javanica using primers Fjav/Rjav, but negative for M. incognita by Finc/Rinc and M. arenaria by Far/Rar as described by Zijlstra et al. (2000). Based on morphological characteristics and molecular analyses, the root-knot nematodes infecting ginger and turmeric were identified as M. javanica. After confirmation of the nematode species, a test was conducted in the greenhouse to assess the pathogenicity of the nematode on ginger and turmeric. Five seedlings per plant species (cultivars unknown) were grown in 15 cm-diam plastic pots containing equal parts of pasteurized field soil and sand, and then inoculated with 2,000 eggs of M. javanica. The egg suspension was added into three holes around the base of each seedling. Non-inoculated seedlings (n2 = 25) were used as controls. Plants were arranged in completely randomized design and grown at 25 ± 3 °C for 10 weeks. At the termination of the experiment, small galls were noticed on the roots of the inoculated seedlings of both ginger and turmeric. No galls were observed on the roots of non-inoculated plants. Egg were extracted from the galled roots (Hussey and Barker, 1973) yielding an average of 1040 ± 96 and 732 ± 54 eggs per g of root of ginger and turmeric, respectively. On ginger, the nematode produced large numbers of galls and egg masses on both primary and secondary (feeder) roots, but the galls produced on turmeric were often observed only on primary roots (Fig. 1). No symptoms of root-knot nematode infestation including galls or water-soaked lesions were observed on the outer surface of rhizomes of both ginger and turmeric. However, the size of rhizomes in the M. javanica-infested areas was visibly smaller than that in non-infested areas (Fig. 2). A similar reduction in the growth of turmeric rhizomes was also observed. Meloidogyne incognita has been commonly reported as a nematode pest of ginger (Myers et al., 2017) and turmeric (Hall et al., 2017) in the USA and both M. incognita and M. javanica are known to cause damage on these plant hosts (Ray et al., 1995; Singh and Gupta, 2011). To the best of our knowledge, this is the first report of M. javanica on ginger and turmeric in the USA.

Leaf-cutter ants engineer large nitrous oxide hot spots in tropical forests.

Though tropical forest ecosystems are among the largest natural sources of the potent greenhouse gas nitrous oxide (N2O), the spatial distribution of emissions across landscapes is often poorly resolved. Leaf cutter ants (LCA; Atta and Acromyrmex, Myrmicinae) are dominant herbivores throughout Central and South America, and influence multiple aspects of forest structure and function. In particular, their foraging creates spatial heterogeneity by concentrating large quantities of organic matter (including nitrogen, N) from the surrounding canopy into their colonies, and ultimately into colony refuse dumps. Here, we demonstrate that refuse piles created by LCA species Atta colombica in tropical rainforests of Costa Rica provide ideal conditions for extremely high rates of N2O production (high microbial biomass, potential denitrification enzyme activity, N content and anoxia) and may represent an unappreciated source of heterogeneity in tropical forest N2O emissions. Average instantaneous refuse pile N2O fluxes surpassed background emissions by more than three orders of magnitude (in some cases exceeding 80 000 µg N2O-N m-2 h-1) and generating fluxes comparable to or greater than those produced by engineered systems such as wastewater treatment tanks. Refuse-concentrating Atta species are ubiquitous in tropical forests, pastures and production ecosystems, and increase density strongly in response to disturbance. As such, LCA colonies may represent an unrecognized greenhouse gas point source throughout the Neotropics.

Identification and characterization of a mosquito-specific eggshell organizing factor in Aedes aegypti mosquitoes.

Mosquito-borne diseases are responsible for several million human deaths annually around the world. One approach to controlling mosquito populations is to disrupt molecular processes or antagonize novel metabolic targets required for the production of viable eggs. To this end, we focused our efforts on identifying proteins required for completion of embryonic development that are mosquito selective and represent potential targets for vector control. We performed bioinformatic analyses to identify putative protein-coding sequences that are specific to mosquito genomes. Systematic RNA interference (RNAi) screening of 40 mosquito-specific genes was performed by injecting double-stranded RNA (dsRNA) into female Aedes aegypti mosquitoes. This experimental approach led to the identification of eggshell organizing factor 1 (EOF1, AAEL012336), which plays an essential role in the formation and melanization of the eggshell. Eggs deposited by EOF1-deficient mosquitoes have nonmelanized fragile eggshells, and all embryos are nonviable. Scanning electron microscopy (SEM) analysis identified that exochorionic eggshell structures are strongly affected in EOF1-deficient mosquitoes. EOF1 is a potential novel target, to our knowledge, for exploring the identification and development of mosquito-selective and biosafe small-molecule inhibitors.

Test for association between dieldrin resistance and 2La inversion polymorphism in Anopheles coluzzii from Lagos, Nigeria.

The assortment of paracentric chromosomal inversion 2La is associated with the maintenance of dieldrin resistance in laboratory colonies of the malaria vector Anopheles gambiae. This association has not been tested in field populations. The aim of this study was to test the association between inversion 2La and dieldrin resistance in a field population of An. coluzzii in Nigeria. Field collected immature stages of Anopheles were raised to adults and exposed to 4% dieldrin according to WHO criteria. Knockdown was recorded at 10 min intervals for 1 hour and final mortality was recorded 24 hours post exposure. Species and inversion 2La diagnostic PCR assays were conducted on the resistant and susceptible mosquitoes. The mosquitoes were highly resistant to 4% dieldrin (17.1% knock down and 25.7% final mortality; KDT50 and KDT95 calculated as 170 and 1, 514 minutes respectively). Frequencies of 2La in both the resistant and susceptible cohorts assorted within HardyWeinberg estimates (χ2=1.32, p=0.8 for dead/susceptible mosquitoes and χ2=2.54, p=0.5 for survivors or resistant mosquitoes). However, a higher number of heterozygous mosquitoes were observed in the resistant cohort compared to the susceptible, with significant variation in karyotype frequencies (χ2=11.08, DF=2, p<0.05) and a significantly higher frequency of the 2La inversion arrangement in the resistant cohort (Pearson's χ2 = 4.58, p = 0.03.). These data are the first to associate paracentric chromosome inversion 2La and dieldrin resistance in field population of An. coluzzii. Dieldrin resistance shows a weak but significant association with 2La whose assortment is affected by positive heterosis. Variation in the assortment of 2La inversion arrangements between resistant and susceptible cohorts of this An. coluzzii population suggests that dieldrin resistance is at least partially linked to inversion 2La which may explain the persistence of dieldrin resistance in this population despite a significant absence of selection for resistance to this insecticide.