Dynamics of bacterial blight disease in resistant and susceptible rice varieties

Bacterial blight (X. oryzae pv. oryzae) is a serious disease in rice across the world. To better control the disease, it is important to understand its epidemiology and how key aspects of this (e.g. infection efficiency, and spatial spread) change according to environment (e.g. local site conditions and season), management, and in particular, variety resistance. To explore this, we analysed data on the disease progress on resistant and susceptible varieties of rice grown at four sites in the Philippines across five seasons using a combination of mechanistic modelling and statistical analysis. Disease incidence was generally lower in the resistant variety. However, we found no evidence that the primary infection efficiency was lower in resistant varieties, suggesting that differences were largely due to reduced secondary spread. Despite secondary spread being attributed to splash dispersal which is exacerbated by wind and rain, the wetter sites of Pila and Victoria in south Luzon tended to have lower infection rates than the drier sites in central Luzon. Likewise, we found spread in the dry season can be substantial and should therefore not be ignored. In fact, we found site to be a greater determinant of the number of infection attempts suggesting that other environmental and management factors had greater effect on the disease than climate. Primary infection was characterised by spatially-random observations of disease incidence. As the season progressed, we observed an emerging short-range (1.6 m–4 m) spatial structure suggesting secondary spread was predominantly short-range, particularly where the resistant variety was grown.

High Seedling Mortality of Scots Pine Caused by Heterobasidion annosum s.s.

This study provides new information on the infection biology and pathogenicity of an important root-rot fungus, Heterobasidion annosum sensu stricto (Fr.) Bref., through a detailed examination of the vegetative spread of clonal individuals and their capacity to produce fruiting bodies on young pine seedlings. The seedlings were planted in a clear-cutting area (c. 1.2 ha in size) after a pine generation that showed slight external symptoms of Heterobasidion root rot. The first dead seedlings were found five years after planting and during a nine-year monitoring period; nearly 600 seedlings were killed by H. annosum s.s. in 48 individual disease centers. Based on pairing tests of 482 isolates, 117 different H. annosum s.s. genotypes were identified. On average, 2.9 genotypes occurred in a single disease center. The extensive secondary spread of genotypes within root systems (up to 48 pine seedlings infected by the same genotype) resulted in annually expanding disease centers. In addition, more than half of the seedlings killed by H. annosum s.s. produced perennial fruiting bodies thus providing air-borne inoculum. The risk of spore infection should be taken into account in any type of cutting operation in young pine stands. Moreover, new control measures directed towards the secondary spread of H. annosum s.s. in pine regeneration are urgently needed in order to maintain the productivity of the pine forest on infested sites.

Examining the spread of Aquatic Invasive Species, Bythothephes longimanus, In Inland Lakes Across Ontario

The purpose of this study is to is to examine the secondary spread of Bythothephes longimanus, commonly known as spiny water flea, across inland lakes in Ontario, and potentially determine predictors for the its invasion. Data for 190 inland lakes across 84 quaternary watersheds in Ontario were included in the database. Global Moran's I was used to analyze the spatial autocorrelation of the variables, and McFadden's Rho-Squared was used to determine if a variable was a predictor of invasion. Three independent variables, out of 28, were found to be good predictors of invasion: (1) mean temperature of watersheds during summer (MNTMPWSSU), (2) mean precipitation for watersheds during spring (MNPCPWSSP), and (3) mean precipitation for watersheds during summer (MNPCPWSSU). Of the three, mean precipitation for watersheds during summer was determined to be the best predictor.

Examining the spread of Aquatic Invasive Species, Bythothephes longimanus, In Inland Lakes Across Ontario

The purpose of this study is to is to examine the secondary spread of Bythothephes longimanus, commonly known as spiny water flea, across inland lakes in Ontario, and potentially determine predictors for the its invasion. Data for 190 inland lakes across 84 quaternary watersheds in Ontario were included in the database. Global Moran's I was used to analyze the spatial autocorrelation of the variables, and McFadden's Rho-Squared was used to determine if a variable was a predictor of invasion. Three independent variables, out of 28, were found to be good predictors of invasion: (1) mean temperature of watersheds during summer (MNTMPWSSU), (2) mean precipitation for watersheds during spring (MNPCPWSSP), and (3) mean precipitation for watersheds during summer (MNPCPWSSU). Of the three, mean precipitation for watersheds during summer was determined to be the best predictor.

Treatment of a giant hepatic echinococcal cyst with percutaneous drainage and in vivo assessment of the protoscolicidal effect of praziquantel

Therapy choices for cystic echinococcisis (CE) are stage-specific: surgical, minimally invasive, medical or observation without intervention. PAIR (percutaneous aspiration, instillation of a scolicide, and re-aspiration) has been considered the treatment of choice for uncomplicated echinococcal liver cysts. However, PAIR carries the risk of toxic cholangitis or hypernatremia and that the cyst frequently refills with bile after withdrawing the catheter. We treated a patient with a giant CE 1 liver cyst with puncture drainage (PD) under albendazole coverage. Drainage enabled us to monitor the morphology of protoscolices under praziquantel (PZQ) co-medication. Protoscolices degenerated within 5 days of PZQ 50 mg/kg/d. The cyst cavity solidified with no evidence of reactivation or secondary spread. Percutaneous treatments can replace surgery in a significant number or cases with hepatic CE. PD allows to assess microscopically the viability of protoscolices under co-medication with PZQ–albendazole and to avoid the instillation of topical scolicides.

Indian cassava mosaic virus (Indian cassava mosaic).

Other than their countries of origin, India and Sri Lanka for ICMV and SLCMV, respectively, SLCMV has also been reported in India (Dutt et al., 2005; Jose et al., 2011) and Cambodia (Wang et al., 2016) while new strains of ICMV have been identified as causative agents of Jatropha curcas mosaic disease in Jatropha curcas from India (Snehi et al., 2012), Nigeria (Kashina et al., 2013) and Singapore (Wang et al., 2014). The primary means of spread of both viruses is via movement of infected cassava cuttings while secondary spread is facilitated by members of the Bemisia tabaci complex. Both ICMV and SLCMV are not on the IUCN or ISSG alert lis.

Day Camp in the Time of COVID-19: What Went Right?

ObjectiveTo evaluate whether a successful camp experience can be achieved with implementation of COVID-19 education, screening and hygiene protocols, and designated cohorts during the summer of 2020.Study DesignA survey study of summer day camp directors in the metro-New York area was conducted in September, 2020. The survey inquired about camper demographics, COVID-10 related policies, and the number of COVID-19 cases and exposures at each camp.ResultsResponses were received from 77% (23/30) of camp directors at the completion of the 2020 summer. There were 8,480 camper children and 3,698 staff across the 23 camps surveyed. A variety of precautions were taken to limit COVID-19 incidence among campers and staff, most often including COVID-19 screening at entry, cohorting campers, maximizing outdoor activities, mandating mask use when indoors, and frequent hand sanitizing. Six staff and one camper tested positive for COVID-19. There was no secondary spread within the staff or campers in any of the camps.ConclusionCamps successfully stayed open in the summer of 2020. The low level of COVID-19 in the community was critical to the initial success of camp opening. Policies that were consistent and maintained among the camps helped prevent further spread.

Differentiating uterine sarcoma from leiomyoma: BET1T2ER Check!

Although rare, uterine sarcoma is a diagnosis that no one wants to miss. Often benign leiomyomas (fibroids) and uterine sarcomas can be differentiated due to the typical low T2 signal intensity contents and well-defined appearances of benign leiomyomas compared to the suspicious appearances of sarcomas presenting as large uterine masses with irregular outlines and intermediate T2 signal intensity together with possible features of secondary spread. The problem is when these benign lesions are atypical causing suspicious imaging features. This article provides a review of the current literature on imaging features of atypical fibroids and uterine sarcomas with an aide-memoire BET1T2ER Check! to help identify key features more suggestive of a uterine sarcoma.

Possible Enhancement of Photodynamic Therapy (PDT) Colorectal Cancer Treatment when Combined with Cannabidiol

: Colorectal cancer (CRC) has a high mortality rate and is one of the most difficult diseases to manage due to tumour resistance and metastasis. The treatment of choice for CRC is reliant on the phase and time of diagnosis. Despite several conventional treatments available to treat CRC (surgical excision, chemo-, radiation- and immune-therapy), resistance is a major challenge, especially if it has metastasized. Additionally, these treatments often cause unwanted adverse side effects and so it remains imperative to investigate, alternative combination therapies. Photodynamic Therapy (PDT) is a promising treatment modality for the primary treatment of CRC, since it is non-invasive, has few side effects and selectively damages only cancerous tissues, leaving adjacent healthy structures intact. PDT involves three fundamentals: a Photosensitizer (PS) drug localized in tumour tissues, oxygen and light. Upon PS excitation using a specific wavelength of light, an energy transfer cascade occurs, that ultimately yields cytotoxic species, which in turn induces cell death. Cannabidiol (CBD) is a cannabinoid compound derived from the Cannabis sativa plant, which is found to exert anticancer effects on CRC through different pathways, inducing apoptosis and so inhibits tumour metastasis and secondary spread. This review paper highlights current conventional treatment modalities for CRC and their limitations, as well as discusses the necessitation for further investigation into unconventional active nanoparticle targeting PDT treatments for enhanced primary CRC treatment. This can be administered in combination with CBD, to prevent CRC secondary spread and so enhance the synergistic efficacy of CRC treatment outcomes, with less side effects.

Complex patterns of secondary spread without loss of genetic diversity in invasive populations of the Asian shore crab Hemigrapsus takanoi (Decapoda) along European coasts

Genetic studies of introduced non-native species are a valuable tool to investigate invasion history and pathways, source populations and multiple introductions of alien species, as well as evolutionary genetic changes following establishment in a new environment. We used a set of nine polymorphic microsatellites to analyse the population genetic structure of the introduced Asian shore crab Hemigrapsus takanoi along European coasts. Our dataset covered the complete known European range of the species, including the most recent records from Great Britain and the southwestern Baltic Sea. The results showed a similarly high genetic diversity of H. takanoi throughout Europe, and no indication of genetic bottlenecks during secondary spread, even in the most recently established populations. Analyses for population structure along geographic regions gave support for a separation between the Bay of Seine populations (northern France) and all other populations. Genetic differentiation within the North and Baltic Seas was more subtle and patchy, hinting to potential unrecognised introduction events, dispersal barriers and anthropogenic vector activity. The populations from the Baltic Sea and Great Britain clustered with the Wadden Sea populations, suggesting secondary introductions from the southeastern North Sea as likely invasion pathways. In summary, we suggest that a combination of anthropogenic secondary spread and the species’ reproductive biology have prevented a loss of genetic diversity during its ongoing expansion. We argue that genetic data depicting population status shortly after an introduction event—like the British and Baltic Sea populations of H. takanoi—may provide important baseline data for investigations of genetic changes during establishment and adaptation processes.