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Since the development of next-generation sequencing techniques and with the growing interest in transcriptomic studies, there is a demand for high-throughput RNA extraction techniques. General RNA extraction protocols are unreliable when it comes to the quality and quantity of isolated RNA obtained from different tissue types of different plant species. Despite Norway spruce (Picea abies) being one of the most significant and commercially valuable tree species in European forests, only limited genetic research is available. In this study, we developed a cetyltrimethylammonium bromide (CTAB) protocol by modifying the original method. We compared this CTAB protocol with other widely used methods for extracting RNA from different tissues (needle, phloem, and root) of Norway spruce, known for its richness in polyphenols, polysaccharides, and secondary metabolites. The modified CTAB method proves to be superior to the kit-based and TRIzol-based methods for extracting RNA from the metabolite-rich tissues of Norway spruce, resulting in high RNA quality and integrity values (RIN~7-9). The modified CTAB RNA extraction method is rapid, cost-effective, and relatively simple in yielding the desired RNA quality from Norway spruce tissues. It is optimal for RNA sequencing and other downstream molecular applications.

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Host shift is ecologically advantageous and a crucial driver for herbivore insect speciation. Insects on the non-native host obtain enemy-free space and confront reduced competition, but they must adapt to survive. Such signatures of adaptations can often be detected at the gene expression level. It is astonishing how bark beetles cope with distinct chemical environments while feeding on various conifers. Hence, we aim to disentangle the six-toothed bark beetle (Ips sexdentatus) response against two different conifer defences upon host shift (Scots pine to Norway spruce). We conducted bioassay and metabolomic analysis followed by RNA-seq experiments to comprehend the beetle's ability to surpass two different terpene-based conifer defence systems. Beetle growth rate and fecundity were increased when reared exclusively on spruce logs (alternative host) compared to pine logs (native host). Comparative gene expression analysis identified differentially expressed genes (DEGs) related to digestion, detoxification, transporter activity, growth, signalling, and stress response in the spruce-feeding beetle gut. Transporter genes were highly abundant during spruce feeding, suggesting they could play a role in pumping a wide variety of endogenous and xenobiotic compounds or allelochemicals out. Trehalose transporter (TRET) is also up-regulated in the spruce-fed beetle gut to maintain homeostasis and stress tolerance. RT-qPCR and enzymatic assays further corroborated some of our findings. Taken together, the transcriptional plasticity of key physiological genes plays a crucial role after the host shift and provides vital clues for the adaptive potential of bark beetles on different conifer hosts.

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Cryptococcus neoformans infection is the most common fungal infection of the central nervous system (CNS) in advanced human immunodeficiency virus (HIV) and acquired immunodeficiency syndrome (AIDS) patients, but remains a relatively uncommon CNS infection in both the immunocompromised and immunocompetent patient population, rendering it a somewhat elusive and frequently overlooked diagnosis. The morbidity and mortality associated with CNS cryptococcal infection can be significantly reduced by early recognition of the imaging appearances by the radiologist in order to focus and expedite clinical management and treatment. The emergence and evolution of anti-retroviral therapy have also impacted significantly on the imaging appearances, morbidity, and mortality of this neuro-infection. The constellation of varied imaging appearances associated with cryptococcal CNS infection in the HIV and AIDS population in the era of highly active anti-retroviral therapy (HAART) will be presented in this review.

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BACKGROUND: There is an increasing recognition that modelling and simulation can assist in the process of designing health care policies, strategies and operations. However, the current use is limited and answers to questions such as what methods to use and when remain somewhat underdeveloped. AIM: The aim of this study is to provide a mechanism for decision makers in health services planning and management to compare a broad range of modelling and simulation methods so that they can better select and use them or better commission relevant modelling and simulation work. METHODS: This paper proposes a modelling and simulation method comparison and selection tool developed from a comprehensive literature review, the research team's extensive expertise and inputs from potential users. Twenty-eight different methods were identified, characterised by their relevance to different application areas, project life cycle stages, types of output and levels of insight, and four input resources required (time, money, knowledge and data). RESULTS: The characterisation is presented in matrix forms to allow quick comparison and selection. This paper also highlights significant knowledge gaps in the existing literature when assessing the applicability of particular approaches to health services management, where modelling and simulation skills are scarce let alone money and time. CONCLUSIONS: A modelling and simulation method comparison and selection tool is developed to assist with the selection of methods appropriate to supporting specific decision making processes. In particular it addresses the issue of which method is most appropriate to which specific health services management problem, what the user might expect to be obtained from the method, and what is required to use the method. In summary, we believe the tool adds value to the scarce existing literature on methods comparison and selection.

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AIM: The development of effective multiple drug regimens for treating human immunodeficiency virus (HIV) are associated with nonadherence in children. HIV-positive children also have a higher incidence of malnutrition. Placement of a percutaneous endoscopic gastrostomy (PEG) is a potential solution. Primary outcome was to determine the complications of PEG placement in a pediatric HIV-positive population. MATERIALS AND METHODS: A 10 year retrospective data analysis was carried out on all HIV-positive children undergoing insertion of a PEG at two institutions. Parameters examined included infections, leakage, displacement, reasons for removal, total time in situ, HIV stage, CD4 count, and serological investigation. Data were compared against published data for PEG insertion in pediatric oncology patients and other comparable pediatric series using Fisher's exact test. RESULTS: Eighteen children were identified, with a median age 35 months and follow-up of 62 months. The majority of patients had advanced disease (Stage C; 65%). Fifty percent of PEGs were inserted for feeding supplementation and all were used for the administration of medications. Sixty-one percent experienced a minor complication; 5/18 (27.7%) experienced peristomal infection; 2/18 (11.1%) experienced either bleeding, leakage, or excessive granulation; and 1/18 (5.6%) experienced dislodgement. Stage of HIV did not affect the incidence of bleeding or infection: 5/11(Stage C) versus 2/7(Stage B) (P = .3). There was no significant difference for major complications when compared with any series though comparison with a large pediatric series revealed a significant difference for minor complications 11/18 versus 27/120 (P = .0003). CONCLUSIONS: There is a low rate of serious complications with PEG insertion in our patients, and the rate is comparable to that seen in pediatric oncology patients. The minor complication rate is, however, higher than a nonimmune compromised population; and careful follow-up for these patients is recommended so that the appropriate therapy can be promptly initiated.

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HealthGrids represent the next generation of advanced healthcare IT and hold the promise to untangle complex healthcare-data problems by integrating health information systems and healthcare entities. Healthcare could benefit from a new delivery approach using HealthGrids to better meet the biomedical and health-related needs. Specialized services are needed to provide unified discovery of and ubiquitous access to available HealthGrid resources. The different types of services available on HealthGrids are classified into two levels, the operational-level services and the management-level services. This paper takes a fresh approach to address the problems of resource discovery in HealthGrids based on Web services (WS) and WS technologies and proposes a WS-based resource discovery model.

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