Analysis of the Changes in the Oxidation of Brain Tissue Cytochrome-c-Oxidase in Traumatic Brain Injury Patients during Hypercapnoea A Broadband NIRS Study

Using broadband near-infrared spectroscopy (NIRS) and cerebral micro-dialysis (MD), we investigated cerebral cellular metabolism and mitochondrial redox states, following hypercapnoea in 6 patients with traumatic brain injury (TBI). In all patients hypercapnoea increased intracranial pressure and cerebral blood flow velocity measured with transcranial Doppler. Despite the likely increase in cerebral oxygen delivery, we did not see an increase in the oxidation status of cytochrome-c-oxidase [oxCCO] in every patient. Analysis of the NIRS data demonstrated two patterns of the changes; Group A (n = 4) showed an increase in [oxCCO] of 0.34(+/-0.34)mu M and Group B (n = 2) a decrease of 0.40(+/- 0.41)mu M. Although no obvious association was seen between the Delta[oxCCO] and the MD, measured changes in lactate and pyruvate concentrations. Further work using model informed data interpretation may be helpful in understanding the multimodal signals acquired in this heterogeneous patient group

Overcoming barriers to effective early parenting interventions for attention-deficit hyperactivity disorder (ADHD): parent and practitioner views

BackgroundThe importance of early intervention approaches for the treatment of attention-deficit hyperactivity disorder (ADHD) has been increasingly acknowledged. Parenting programmes (PPs) are recommended for use with preschool children with ADHD. However, low take-up' and high drop-out' rates compromise the effectiveness of such programmes within the community. MethodsThis qualitative study examined the views of 25 parents and 18 practitioners regarding currently available PPs for preschool children with ADHD-type problems in the UK. Semi-structured interviews were undertaken to identify both barriers and facilitators associated with programme access, programme effectiveness, and continued engagement. Results and conclusionsMany of the themes mirrored previous accounts relating to generic PPs for disruptive behaviour problems. There were also a number of ADHD-specific themes. Enhancing parental motivation to change parenting practice and providing an intervention that addresses the parents' own needs (e.g. in relation to self-confidence, depression or parental ADHD), in addition to those of the child, were considered of particular importance. Comparisons between the views of parents and practitioners highlighted a need to increase awareness of parental psychological barriers among practitioners and for better programme advertising generally. Clinical implications and specific recommendations drawn from these findings are discussed and presented

Caenorhabditis elegans as a model system for studying drug induced mitochondrial toxicity

Today HIV-1 infection is recognized as a chronic disease with obligatory lifelong treatment to keep viral titers below detectable levels. The continuous intake of antiretroviral drugs however, leads to severe and even life-threatening side effects, supposedly by the deleterious impact of nucleoside-analogue type compounds on the functioning of the mitochondrial DNA polymerase. For detailed investigation of the yet partially understood underlying mechanisms, the availability of a versatile model system is crucial. We therefore set out to develop the use of Caenorhabditis elegansto study drug induced mitochondrial toxicity. Using a combination of molecular-biological and functional assays, combined with a quantitative analysis of mitochondrial network morphology, we conclude that anti-retroviral drugs with similar working mechanisms can be classified into distinct groups based on their effects on mitochondrial morphology and biochemistry. Additionally we show that mitochondrial toxicity of antiretroviral drugs cannot be exclusively attributed to interference with the mitochondrial DNA polymerase

The role of prenatal alcohol exposure in abruptio placentae

Objective. To investigate the association between preconception and prenatal alcohol use and abruptio placentae. Methods. A case-control study of women with the clinical diagnosis of abruptio placentae, 65 cases and 66 controls, at Tygerberg Academic Hospital, Western Cape, South Africa. Women in whom a retroplacental blood clot, covering at least 15% of the placental surface, was found at delivery at 24 weeks’ gestation or later were asked to complete a timeline follow-back questionnaire to determine their alcohol intake 12 and 3 months before and during pregnancy. The same questionnaire was administered to a control group of high-risk women who had no antepartum haemorrhage. Outcome. Women who drank alcohol 12 months before conception were more than 4 times more likely to develop abruptio placentae than the control group (odds ratio (OR) 4.49, p=0.00009). Women who drank alcohol 3 months prior to conception were 3 times more likely to develop abruptio placentae than the control group (OR 3.06, p=0.003). Drinking alcoholic beverages during pregnancy carried a more than 3 times greater risk of developing abruptio placentae (OR 3.52, p=0.0006). In the study group, women consumed a mean of 13.6, 12.0 and 11.2 standard drinks in a typical week at 12 and 3 months before and during pregnancy, respectively. The study group demonstrated a binge-drinking pattern, with two to four sessions per month. Conclusion. An association was found between preconception and prenatal consumption of alcohol and abruptio placentae

Common carp (Cyprinus carpio L.) alters its feeding niche in response to changing food resources: direct observations in simulated ponds

We used customized fish tanks as model fish ponds to observe grazing, swimming, and conspecific social behavior of common carp (Cyprinus carpio) under variable food-resource conditions to assess alterations in feeding niche. Different food and feeding situations were created by using only pond water or pond water plus pond bottom sediment or pond water plus pond bottom sediment and artificial feeding. All tanks were fertilized twice, prior to stocking and 2 weeks later after starting the experiment to stimulate natural food production. Common carp preferred artificial feed over benthic macroinvertebrates, followed by zooplankton. Common carp did not prefer any group of phytoplankton in any treatment. Common carp was mainly benthic in habitat choice, feeding on benthic macroinvertebrates when only plankton and benthic macroinvertebrates were available in the system. In the absence of benthic macroinvertebrates, their feeding niche shifted from near the bottom of the tanks to the water column where they spent 85% of the total time and fed principally on zooplankton. Common carp readily switched to artificial feed when available, which led to better growth. Common carp preferred to graze individually. Behavioral observations of common carp in tanks yielded new information that assists our understanding of their ecological niche. This knowledge could be potentially used to further the development of common carp aquaculture

Role of dissolved nitrate and phosphate in isolates of Mesodinium rubrum and toxin-producing Dinophysis acuminata

Mesodinium rubrum (as prey) is a critical component, in addition to light, for growth and toxin production by the mixotrophic dinoflagellate Dinophysis acuminata. Little is known, however, about the role that dissolved inorganic nutrients play in this predator-prey relationship and system toxicity. A series of experiments were conducted to investigate the possible uptake of dissolved nitrate and phosphate by (1) D. acuminata starved of prey, (2) D. acuminata feeding on M. rubrum, and (3) M. rubrum grown in nutritionally modified medium. All single-clone or mixed cultures were monitored for dissolved and particulate nutrient levels over the growth cycle, as well as for growth rate, biomass, and toxin production when appropriate. Dinophysis acuminata did not utilize dissolved nitrate or phosphate in the medium under nutrient-enriched or nutrientreduced regimes, in the absence or presence of prey, or during any growth phase monitored. Changes in particulate phosphorus and nitrogen in D. acuminata were instead strongly influenced by the consumption of M. rubrum prey, and these levels quickly stabilized once prey were no longer available. Mesodinium rubrum, in contrast, rapidly assimilated dissolved nitrate and phosphate, with maximum uptake rates of 1.38 pmol N cell(-1) d(-1) and 1.63 pmol P cell(-1) d(-1), respectively. While D. acuminata did not benefit directly from the dissolved nitrate and phosphate, its growth (0.37 +/- 0.01 d(-1)) and toxin production rates for okadaic acid, dinophysistoxin-1 and pectenotoxin-2 (0.1, 0.9 and 2.6 pg cell(-1) d(-1), respectively) were directly coupled to prey availability. These results suggest that while dissolved nitrate and phosphate do not have a direct effect on toxin production or retention by D. acuminata, these nutrient pools contribute to prey growth and biomass, thereby indirectly influencing D. acuminata blooms and overall toxins in the system

Distribution and conservation status of two endemic Tasmanian crustaceans, Allanaspides hickmani and Allanaspides helonomus (Syncarida: anaspididae)

Extant representatives of the ancient crustacean family Anaspididae (Syncarida) are restricted to the island state of Tasmania, Australia. The most recently described species, Allanaspides helonomus Swain, Wilson, Hickman & Ong, 1970 and A. hickmani Swain, Wilson & Ong, 1971, were described from buttongrass moorland in southwestern Tasmania. Large areas of their habitat were subsequently inundated for hydroelectric power generation. We surveyed the extant distributions of A. hickmani and A. helonomus, assessed potential threats to the species, and reviewed their conservation status against state, national and international criteria. A. hickmani is restricted to a single catchment and occurs in a very small number (<10) of highly fragmented subpopulations on the margins of two hydroelectric impoundments. A. helonomus has a substantially larger range and Area of Occupancy spanning three separate catchments, and is now known to also occur in the Lake Pedder hydro-electric impoundment. Both species are listed as vulnerable on the IUCN Red List. This listing appears warranted for A. hickmani based on its restricted Area of Occupancy and the small number of extant subpopulations. However, A. helonomus no longer appears to fulfil the IUCN criterion for vulnerable. Neither species appears to be eligible for listing as vulnerable under the Australian Environment Protection and Biodiversity Conservation Act 1999 and the Tasmanian Threatened Species Protection Act 1995. The current listing of A. hickmani as rare under the Tasmanian Threatened Species Protection Act 1995 appears warranted as extant subpopulations may be at risk of extinction. The level of risk for A. helonomus is considerably lower than is the case for A. hickmani, and A. helonomus may not be eligible for listing as rare. The potential impacts of climate change on buttongrass moorland may present the most serious long-term threat to the two Allanaspides species

RepSeq-A database of amino acid repeats present in lower eukaryotic pathogens

BACKGROUND Amino acid repeat-containing proteins have a broad range of functions and their identification is of relevance to many experimental biologists. In human-infective protozoan parasites (such as the Kinetoplastid and Plasmodium species), they are implicated in immune evasion and have been shown to influence virulence and pathogenicity. RepSeq http://repseq.gugbe.com is a new database of amino acid repeat-containing proteins found in lower eukaryotic pathogens. The RepSeq database is accessed via a web-based application which also provides links to related online tools and databases for further analyses. RESULTS The RepSeq algorithm typically identifies more than 98% of repeat-containing proteins and is capable of identifying both perfect and mismatch repeats. The proportion of proteins that contain repeat elements varies greatly between different families and even species (3 - 35% of the total protein content). The most common motif type is the Sequence Repeat Region (SRR) - a repeated motif containing multiple different amino acid types. Proteins containing Single Amino Acid Repeats (SAARs) and Di-Peptide Repeats (DPRs) typically account for 0.5 - 1.0% of the total protein number. Notable exceptions are P. falciparum and D. discoideum, in which 33.67% and 34.28% respectively of the predicted proteomes consist of repeat-containing proteins. These numbers are due to large insertions of low complexity single and multi-codon repeat regions. CONCLUSION The RepSeq database provides a repository for repeat-containing proteins found in parasitic protozoa. The database allows for both individual and cross-species proteome analyses and also allows users to upload sequences of interest for analysis by the RepSeq algorithm. Identification of repeat-containing proteins provides researchers with a defined subset of proteins which can be analysed by expression profiling and functional characterisation, thereby facilitating study of pathogenicity and virulence factors in the parasitic protozoa. While primarily designed for kinetoplastid work, the RepSeq algorithm and database retain full functionality when used to analyse other species