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The family of logistic type distributions has been widely studied and applied in the literature. However, certain estimation problems exist in some members of this family. Particularly, the three-parameter type I generalized logistic distribution presents these problems, where the parameter space must be restricted for the existence of their maximum likelihood estimators. In this paper, motivated by the complexities that arise in the inference under the likelihood approach utilizing this distribution, we propose a Bayesian approach to solve these problems. A simulation study is carried out to assess the performance of some posterior distributional characteristics, such as the mean, using Monte Carlo Markov chain methods. To illustrate the potentiality of the Bayesian estimation in the three-parameter type I generalized logistic distribution, we apply the proposed method to real-world data related to the copper metallurgical engineering area.

Actualmente, el ejercicio de funciones jurisdiccionales atribuidas a las autoridades administrativas ha generado interpretaciones judiciales confusas, en la aplicación de medidas cautelares innominadas para la protección de derechos de autor y conexos en Colombia; así lo evidencia el análisis realizado a las medidas cautelares descritas en la Ley 1493 del año 2011, que otorgó competencias de inspección, vigilancia y control sobre las sociedades de gestión colectiva de derechos de autor y conexos; en este sentido se requiere describir las funciones jurisdiccionales de la Dirección Nacional de Derecho de Autor respecto a las medidas cautelares y su importancia en la protección de los derechos de autor y conexos, al igual que analizar las medidas cautelares innominadas desde su origen, las características y lo propuesto por la Corte Constitucional en materia de funciones jurisdiccionales de la Dirección Nacional de Derecho de Autor y respecto de la procedencia de las medidas cautelares innominadas como competencia de esta entidad. Se concluye que las medidas cautelares nominadas no son suficientes, y que se hace necesario acudir a las medidas cautelares innominadas, como herramienta jurídica del funcionario administrativo, sin que ello implique arbitrariedad y prejuzgamiento en el proceso.

Background: No in-shoe systems, measuring both components of plantar load (plantar pressure and shear stress) are available for use in patients with diabetes. The STAMPS (STrain Analysis and Mapping of the Plantar Surface) system utilises digital image correlation (DIC) to determine the strain sustained by a deformable insole, providing a more complete understanding of plantar shear load at the foot-surface interface., Research Questions: What is the normal range and pattern of strain at the foot-surface interface within a healthy population as measured by the STAMPS system? Is STAMPS a valid tool to measure the effects of plantar load?, Methods: A cross-sectional study of healthy participants was undertaken. Healthy adults without foot pathology or diabetes were included. Participants walked 20 steps with the STAMPS insole in a standardised shoe. Participants also walked 10 m with the Novel Pedar® plantar pressure measurement insole within the standardised shoe. Both measurements were repeated three times. Outcomes of interest were global and regional values for peak resultant strain (S MAG ) and peak plantar pressure (PPP)., Results: In 18 participants, median peak S MAG and PPP were 35.01 % and 410.6kPa respectively. The regions of the hallux and heel sustained the highest S MAG (29.31 % (IQR 24.56-31.39) and 20.50 % (IQR 15.59-24.12) respectively) and PPP (344.8kPa (IQR 268.3 - 452.5) and 279.3kPa (IQR 231.3-302.1) respectively). S MAG was moderately correlated with PPP (r= 0.65, p < 0.001). Peak S MAG was located at the hallux in 55.6 % of participants, at the 1st metatarsal head (MTH) in 16.7 %, the heel in 16.7 %, toes 3-5 in 11.1 % and the MTH2 in 5.6 %., Significance: The results demonstrate the STAMPS system is a valid tool to measure plantar strain. Further studies are required to investigate the effects of elevated strain and the relationship with diabetic foot ulcer formation., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Coccidiosis and necrotic enteritis (NE) are prevalent poultry ailments worldwide, leading to decreased live performance and elevated mortality rates without antibiotic usage. This study evaluated Nigella sativa (black cumin) seeds (BCS) and kefir as alternatives to antibiotics for broilers. An in vivo study over a 28-day period, using 384 Cobb 500 male broilers organized into six treatment groups as part of a completely randomized block experimental design was conducted. Each treatment group included eight replicates, with each replicate containing eight birds. The treatments included positive control, negative control, antibiotic control, 5% BCS in feed, 20% kefir in drinking water, and a combination of 5% BCS and 20% kefir. NE was induced in broilers by administering ~5000 oocysts of Eimeria maxima orally on day 14, followed by inoculation with about 10 8 CFU/mL of Clostridium perfringens (Cp) (strain Cp#4) on days 19, 20, and 21. Live performance metrics including feed intake, body weight gain, and feed conversion were assessed in broilers. Additionally, NE disease outcomes such as lesion scores, mortality rates, and Cp populations in cecum were determined during the study. The BCS, kefir, and the combination had no detrimental effect on broiler live performance. BCS-treated and combination groups had lower NE scores ( p > 0.05) in comparison to the positive control and exhibited no significant difference ( p > 0.05) from antibiotic control. Additionally, treatment groups and antibiotic control were not significantly different ( p > 0.05) in mortality, whereas the BCS and kefir combination significantly reduced ( p < 0.05) mortality to 14.1% compared to 31.3% for the positive control. C. perfringens vegetative cells significantly decreased ( p < 0.05) in treatments with BCS, kefir, and their combination on days 22 and 28 compared to the positive control. On day 22, Cp sores were significantly lower ( p < 0.05) for the kefir and combination treatments compared to the positive control. In conclusion, BCS and kefir successfully reduced C. perfringens infection and mortality without any detrimental impact on broiler live performance with the combined treatment being the most effective. These results suggest that BCS and kefir could serve as potential alternatives to antibiotics in managing NE., Competing Interests: Greg F. Mathis and Brett S. Lumpkins were employed by Southern Poultry Feed & Research, Inc., Athens, GA, USA. All the authors declare no conflicts of interest.

Diabetic foot ulcers (DFUs) often become infected and are treated with antimicrobials, with samples collected to inform care. Swab samples are easier than tissue sampling but report fewer organisms. Compared with culture and sensitivity (C&S) methods, molecular microbiology identifies more organisms. Clinician perspectives on sampling and processing are unknown. We explored clinician perspectives on DFU sampling-tissue samples/wound swabs-and on processing techniques, culture and sensitivity or molecular techniques. The latter provides information on organisms which have not survived transport to the laboratory for culture. We solicited feedback on molecular microbiology reports. Qualitative study using semi-structured interview, with analysis using a Framework approach. CODIFI2 clinicians from UK DFU clinics. Seven consultants agreed to take part. They reported, overall, a preference for tissue samples over swabbing. Clinicians were not confident replacing C&S with molecular microbiology as the approach to reporting was unfamiliar. The study was small and did not recruit any podiatrists or nurses, who may have discipline-specific attitudes or perspectives on DFU care. Both sampling approaches appear to be used by clinicians. Molecular microbiology reports would not be, at present, suitable for replacement of traditional culture and sensitivity., (© 2024 The Author(s). International Wound Journal published by Medicalhelplines.com Inc and John Wiley & Sons Ltd.)

The poultry industry has significant coccidiosis and necrotic enteritis (NE) challenges, leading to high mortality and unacceptable growth without antibiotic treatment. This research explored supplementing Nigella sativa (black cumin) seed oil in poultry feed to mitigate coccidiosis and prevent or lessen NE in broilers. In vivo studies consisted of 384 and 320 Cobb 500 male broiler chicks distributed in a randomized complete block experimental design for trials 1 and 2, respectively. The first trial compared 3 concentrations (1, 2, and 5 mL/kg) of black cumin seed oil (BCSO), and trial 2 compared 2 concentrations (2 and 5 mL/kg) BCSO, with birds challenged with Eimeria maxima and Clostridium perfringens (Cp) strains Cp#6 and Cp#4, respectively. Broiler live performance, NE disease outcomes, and Cp populations were measured for both trials. A commercially available BCSO oil product, determined in a preliminary in vitro study to have the highest anti-Cp activity, was selected for in vivo studies. Gas chromatography-mass spectrometry analysis indicated the major bioactive compounds p-cymene, thymoquinone, carvacrol, and thymol were present in the BCSO. In trial 1 with strain Cp#6, BCSO concentrations of 2 and 5 mL/kg reduced NE lesion score and mortality rate to 1.6% compared with 7.8% for positive control, with no adverse impact on live performance. In trial 2 with strain Cp#4, BCSO reduced NE lesion scores and mortality rate to 35.9% compared with 51.6% for positive control and also improved weight gain when there was a Cp infection in broiler chickens. The current study compared NE in broilers challenged with 2 different Cp strains producing different levels of NE. Following Cp infection, both the population of vegetative cells and spores of Cp in cecal contents decreased for all treatments in trial 2. In conclusion, BCSO at concentrations of 2 and 5 mL/kg enhanced broiler live performance and alleviated NE and has potential as a natural, non-medication antimicrobial nutritional supplement for use as a feed additive in chickens., (Copyright © 2023. Published by Elsevier Inc.)

Diabetic foot ulceration is driven by peripheral neuropathy, resulting in abnormal foot biomechanics and elevated plantar load. Plantar load comprises normal pressure and tangential shear stress. Currently, there are no in-shoe devices measuring both components of plantar load. The STAMPS (STrain Analysis and Mapping of the Plantar Surface) system was developed to address this and utilises digital image correlation (DIC) to determine the strain sustained by a plastically deformable insole, providing an assessment of plantar load at the foot-surface interface during gait. STAMPS was developed as a multi-layered insole, comprising a deformable mid-layer, onto which a stochastic speckle pattern film is applied. A custom-built imaging platform is used to obtain high resolution pre- and post-walking images. Images are imported into commercially available DIC software (GOM Correlate, 2020) to obtain pointwise strain data. The strain and displacement data are exported and post-processed with custom analysis routines (MATLAB, Mathworks Inc.), to obtain the resultant global and regional peak strain (S MAG ), antero-posterior strain (S AP ) and medio-lateral strain (S ML ). To validate the core technique an experimental test process used a Universal Mechanical Tester (UMT) system (UMT TriboLab, Bruker) to apply controlled vertical and tangential load regimes to the proposed multi-layer insole. A pilot study was then conducted to assess the efficacy of using the STAMPS system to measure in-shoe plantar strain in three healthy participants. Each participant walked 10 steps on the STAMPS insole using a standardised shoe. They also walked 10 m in the same shoe using a plantar pressure measurement insole (Novel Pedar ® ) to record peak plantar pressure (PPP) as a gold-standard comparator. The results of the experimental validation tests show that with increased normal force, at a constant shear distance, S MAG increased in a linear fashion. Furthermore, they showed that with increased shear distance, at a constant force, S MAG increased. The results of the pilot study found participant 1 demonstrated greatest S MAG in the region toes 3-5 (15.31%). The highest mean S MAG for participant 2 was at the hallux (29.31%). Participant 3 exhibited highest strain in the regions of the first and second metatarsal heads (58.85% and 41.62% respectively). Increased PPP was strongly associated with increased S MAG with a Spearman's correlation coefficient 0.673 ( p  < 0.0001). This study has demonstrated the efficacy of a novel method to assess plantar load across the plantar surface of the foot. Experimental testing validated the sensitivity of the method to both normal pressure and tangential shear stress. This technique was successfully incorporated into the STAMPS insole to reliably measure and quantify the cumulative degree of strain sustained by a plastically deformable insole during a period of gait, which can be used to infer plantar loading patterns. Future work will explore how these measures relate to different pathologies, such as regions at risk of diabetic foot ulceration.

Aims: Diabetic foot ulceration (DFU) is a multifactorial process involving undetected, repetitive trauma resulting in inflammation and tissue breakdown. Shear stress forms a major part of plantar load, the aim of this review is to determine whether elevated shear stress results in ulceration., Methods: A systematic review of the Ovid Medline, EMBASE, CINAHL and Cochrane library databases was performed. Studies involving patients with diabetes who underwent plantar shear stress assessment were included. The primary outcome was plantar shear stress in patients with diabetes who had a current/previous DFU compared with those with no prior ulceration. Meta-analysis was performed comparing shear stress between those with a current or previous DFU and those without, and those with diabetes and healthy controls., Results: The search strategy identified 1461 potentially relevant articles, 16 studies met the inclusion criteria, involving a total of 597 patients. Comparing shear stress between the current/previous DFU group and those without: Standardised mean difference (SMD) 0.62 (95% CI -0.01 to 1.25), in favour of greater shear stress within the DFU group, p = 0.05. Comparing shear stress between people with diabetes and healthy controls: 0.36 (95% CI -0.31 to 1.03), in favour of greater shear stress within the diabetes group, p = 0.29., Conclusion: This review suggests that that patients with diabetes and a history of ulceration exhibit greater shear stress than their ulcer-free counterparts. This strengthens the premise that development of systems to measure shear stress may be helpful in DFU prediction and prevention., (© 2021 Diabetes UK.)

For clinical trials where participants pass through a number of discrete health states resulting in longitudinal measures over time, there are several potential primary estimands for the treatment effect. Incidence or time to a particular health state are commonly used outcomes but the choice of health state may not be obvious and these estimands do not make full use of the longitudinal assessments. Multistate models have been developed for some diseases and conditions with the purpose of understanding their natural history and have been used for secondary analysis to understand mechanisms of action of treatments. There is little published on the use of multistate models as the primary analysis method and potential implications on design features, such as assessment schedules. We illustrate methods via analysis of data from a motivating example; a Phase III clinical trial of pressure ulcer prevention strategies. We clarify some of the possible estimands that might be considered and we show, via a simulation study, that under some circumstances the sample size could be reduced by half using a multistate model based analysis, without adversely affecting the power of the trial., (© 2021 The Authors. Statistics in Medicine published by John Wiley & Sons, Ltd.)

Patient-reported outcomes can be included as end points in pressure ulcer (PU) intervention trials to provide information to inform decision-making and improve the lives of patients. However, the challenge for researchers and clinicians is identifying and choosing an appropriate instrument for each particular application that suits their research questions and clinical context. To provide researchers and clinicians with the information needed to inform choice of patient-reported outcome measures, we compared a generic and disease-specific measures' ability to discriminate between clinical groups known to differ, and determined their responsiveness to change. We performed analyses on a subset of patients recruited to the PRESSURE 2 trial that completed the pressure ulcer quality of life instrument-prevention version (PU-QOL-P) and Short Form 12 Questionnaire (SF12) measures at baseline and 30-day posttreatment. Known-group validity and responsiveness-to-change analyses were conducted. The analysis sample consisted of 617 patients that completed both measures at baseline. Known-group validity revealed that some PU-QOL-P symptoms and function scales differentiated between people with category 2 PUs and those without PUs. A less meaningful pattern of results was observed for the SF12 scales, suggesting that the PU-QOL-P is more sensitive to differences between PU and non-PU populations. Responsiveness analysis revealed that the PU-QOL-P was more responsive in detecting disease severity than the SF12. The PU-QOL-P provides a standardized method for assessing PU-specific symptoms and functioning outcomes and is suitable for quantifying the benefits of PU interventions from the patient's perspective. Generic measures are useful for group comparisons of global quality of life domains. Choice of measure for each particular application should be determined by the purpose of the measurement and the information required., (© 2019 by the Wound Healing Society.)

Background: Pressure ulcers represent a major burden to patients, carers and the healthcare system, affecting approximately 1 in 17 hospital and 1 in 20 community patients. They impact greatly on an individual's functional status and health-related quality of life. The mainstay of pressure ulcer prevention practice is the provision of pressure redistribution support surfaces and patient repositioning. The aim of the PRESSURE 2 study is to compare the two main mattress types utilised within the NHS: high-specification foam and alternating pressure mattresses, in the prevention of pressure ulcers., Methods/design: PRESSURE 2 is a multicentre, open-label, randomised, double triangular, group sequential, parallel group trial. A maximum of 2954 'high-risk' patients with evidence of acute illness will be randomised on a 1:1 basis to receive either a high-specification foam mattress or alternating-pressure mattress in conjunction with an electric profiling bed frame. The primary objective of the trial is to compare mattresses in terms of the time to developing a new Category 2 or above pressure ulcer by 30 days post end of treatment phase. Secondary endpoints include time to developing new Category 1 and 3 or above pressure ulcers, time to healing of pre-existing Category 2 pressure ulcers, health-related quality of life, cost-effectiveness, incidence of mattress change and safety. Validation objectives are to determine the responsiveness of the Pressure Ulcer Quality of Life-Prevention instrument and the feasibility of having a blinded endpoint assessment using photography. The trial will have a maximum of three planned analyses with unequally spaced reviews at event-driven coherent cut-points. The futility boundaries are constructed as non-binding to allow a decision for stopping early to be overruled by the Data Monitoring and Ethics Committee., Discussion: The double triangular, group sequential design of the PRESSURE 2 trial will provide an efficient design through the possibility of early stopping for demonstrating either superiority, inferiority of mattresses or futility of the trial. The trial optimises the potential for producing robust clinical evidence on the effectiveness of two commonly used mattresses in clinical practice earlier than in a conventional design., Trial Registration: ISRCTN01151335 . Registered on 14 May 2013. Protocol version: 5.0, dated 25 September 2015 Trial sponsor: Clare Skinner, Faculty Head of Research Support, University of Leeds, Leeds, LS2 9JT; 0113 343 4897; C.E.Skinner@leeds.ac.uk.

Background: Few pain assessment scales have been used in pressure ulcer (PU) research and none developed or validated for people with PUs. We examined the Leeds Assessment of Neuropathic Symptoms and Signs (LANSS) scale to determine its utility as an outcome measure for people with pressure area-related pain., Methods: Leeds Assessment of Neuropathic Symptoms and Signs data from 728 participants underwent psychometric analyses: traditional tests for data quality, scaling assumptions, reliability and validity and a Rasch analysis including tests of fit, spread and targeting of item locations, response dependency, person separation index (reliability) and differential item functioning., Results: Our findings offer support for a unidimensional scale; confirmatory factor analysis indicated a non-significant chi-square test of model fit [(df = 14) 23.48, p = 0.053]. However, some misfit was identified at the overall scale and individual item levels, and internal construct validity of the LANSS as an outcome measure for neuropathic pain in people with pressure area-related pain was not supported; low to moderate item-total correlations [Chi Square (df = 28) 55.546, p = 0.002] and inter-item correlations (mean 0.117 and range from 0.063 to 0.415); and low Cronbach's alpha (0.549) and Person Separation Index (0.334)., Conclusions: Requirements for reliable and valid measurement do not support the use of the LANSS as an outcome measure in people with PUs at the individual level or as a generalized measurement scale of neuropathic pain across ulcer severity groups. Expanding the number of items to aid differentiation between neuropathic pain levels and improving scale reliability is recommended. WHAT DOES THIS STUDY ADD?: The Leeds Assessment of Neuropathic Symptoms and Signs scale (LANSS) is not suitable as an outcome measure of pressure ulcer-related neuropathic pain as it did not meet requirements for reliable and valid measurement in this population., (© 2016 European Pain Federation - EFIC®.)

The genome of the eukaryotic protist Giardia lamblia, an important human intestinal parasite, is compact in structure and content, contains few introns or mitochondrial relics, and has simplified machinery for DNA replication, transcription, RNA processing, and most metabolic pathways. Protein kinases comprise the single largest protein class and reflect Giardia's requirement for a complex signal transduction network for coordinating differentiation. Lateral gene transfer from bacterial and archaeal donors has shaped Giardia's genome, and previously unknown gene families, for example, cysteine-rich structural proteins, have been discovered. Unexpectedly, the genome shows little evidence of heterozygosity, supporting recent speculations that this organism is sexual. This genome sequence will not only be valuable for investigating the evolution of eukaryotes, but will also be applied to the search for new therapeutics for this parasite.

Entamoeba histolytica and Spironucleus barkhanus have genes that encode short iron-dependent hydrogenases (Fe-hydrogenases), even though these protists lack hydrogenosomes. To understand better the biochemistry of the protist Fe-hydrogenases, we prepared a recombinant E. histolytica short Fe-hydrogenase and measured its activity in vitro. A Giardia lamblia gene encoding a short Fe-hydrogenase was identified from shotgun genomic sequences, and RT-PCR showed that cultured entamoebas and giardias transcribe short Fe-hydrogenase mRNAs. A second E. histolytica gene, which encoded a long Fe-hydrogenase, was identified from shotgun genomic sequences. Phylogenetic analyses suggested that the short Fe-hydrogenase genes of entamoeba and diplomonads share a common ancestor, while the long Fe-hydrogenase gene of entamoeba appears to have been laterally transferred from a bacterium. These results are discussed in the context of competing ideas for the origins of genes encoding fermentation enzymes of these protists.

Giardia lamblia and Entamoeba histolytica are amitochondriate, microaerophilic protists which use fermentation enzymes like those of bacteria to survive anaerobic conditions within the intestinal lumen. Genes encoding fermentation enzymes and related electron transport peptides (e.g., ferredoxins) in giardia organisms and amebae are hypothesized to be derived from either an ancient anaerobic eukaryote (amitochondriate fossil hypothesis), a mitochondrial endosymbiont (hydrogen hypothesis), or anaerobic bacteria (lateral transfer hypothesis). The goals here were to complete the molecular characterization of giardial and amebic fermentation enzymes and to determine the origins of the genes encoding them, when possible. A putative giardia [2Fe-2S]ferredoxin which had a hypothetical organelle-targeting sequence at its N terminus showed similarity to mitochondrial ferredoxins and the hydrogenosomal ferredoxin of Trichomonas vaginalis (another luminal protist). However, phylogenetic trees were star shaped, with weak bootstrap support, so we were unable to confirm or rule out the endosymbiotic origin of the giardia [2Fe-2S]ferredoxin gene. Putative giardial and amebic 6-kDa ferredoxins, ferredoxin-nitroreductase fusion proteins, and oxygen-insensitive nitroreductases each tentatively supported the lateral transfer hypothesis. Although there were not enough sequences to perform meaningful phylogenetic analyses, the unique common occurrence of these peptides and enzymes in giardia organisms, amebae, and the few anaerobic prokaryotes suggests the possibility of lateral transfer. In contrast, there was more robust phylogenetic evidence for the lateral transfer of G. lamblia genes encoding an NADH oxidase from a gram-positive coccus and a microbial group 3 alcohol dehydrogenase from thermoanaerobic prokaryotes. In further support of lateral transfer, the G. lamblia NADH oxidase and adh3 genes appeared to have an evolutionary history distinct from those of E. histolytica.

Short introns occur in numerous protist lineages, but there are no reports of intervening sequences in the protists Giardia lamblia and Trichomonas vaginalis, which may represent the deepest known branches in the eukaryotic line of descent. We have discovered a 35-bp spliceosomal intron in a gene encoding a putative [2Fe-2S] ferredoxin of G. lamblia. The Giardia intron contains a canonical splice site at its 3' end (AG), a noncanonical splice site at its 5' end (CT), and a branch point sequence that fits the yeast consensus sequence of TACTAAC except for the first nucleotide (AACTAAC). We have also identified several G. lamblia genes with spliceosomal peptides, including homologues of eukaryote-specific spliceosomal peptides (Prp8 and Prp11), several DExH-box RNA-helicases that have homologues in eubacteria, but serve essential functions in the splicing of introns in eukaryotes, and 11 predicted archaebacteria-like Sm and like-Sm core peptides, which coat small nuclear RNAs. Phylogenetic analyses show the Giardia Sm core peptides are the products of multiple, ancestral gene duplications followed by divergence, but they retain strong similarity to Sm and like-Sm peptides of other eukaryotes. Although we have documented only a single intron in Giardia, it likely has other introns and fully functional, spliceosomal machinery. If introns were added during eukaryotic evolution (the introns-late hypothesis), then these results push back the date of this event before the branching of G. lamblia.

We employed a phylogenomic approach to study the evolution of alpha subunits of the proteasome gene family from early diverging eukaryotes. BLAST similarity searches of the Giardia lamblia genome identified all seven alpha proteasome genes characteristic of eukaryotes from the crown group. In addition, a PCR strategy for the amplification of multiple alpha subunit sequences generated single alpha proteasome products for representatives of the Kinetoplastida (Leishmania major), the Parabasalia (Trichomonas vaginalis), and the Microsporidia (Vairimorpha sp., Nosema sp., Endoreticulata sp., and Spraguea lophii). The kinetoplastid Trypanosoma cruzi and the eukaryote crown group Acanthamoeba castellanii yielded two distinct alpha proteasome genes each. The presence of seven distinct alpha proteasome genes in G. lamblia, one of the earliest-diverging eukaryotes, indicates that the alpha proteasome gene family evolved rapidly from a minimum of one gene in Archaea to seven or more in Eukarya. Results from the phylogenomic analysis are consistent with the idea that the Diplomonida (as represented by G. lamblia), the Kinetoplastida, the Parabasalia, and the Microsporidia diverged after the duplication events that originated the alpha proteasome gene family. A model for the early origin and evolution of the proteasome gene family is presented.

The Giardia genome project database provides an online resource for Giardia lamblia (WB strain, clone C6) genome sequence information. The database includes edited single-pass reads, the results of BLASTX searches, and details of progress towards sequencing the entire 12 million-bp Giardia genome. Pre-sorted BLASTX results can be retrieved based on keyword searches and BLAST searches of the high throughput Giardia data can be initiated from the web site or through NCBI. Descriptions of the genomic DNA libraries, project protocols and summary statistics are also available. Although the Giardia genome project is ongoing, new sequences are made available on a bi-monthly basis to ensure that researchers have access to information that may assist them in the search for genes and their biological function. The current URL of the Giardia genome project database is www.mbl.edu/Giardia.

Swiss-Webster mice were fed corn oil control diet or 0.7% cyclopropenoid fatty acid (CPFA) for 8 weeks and dosed iv with an equimolar suspension of [3H]cholesteryl palmitate and [14C]cholesteryl palmitoleate. Blood decline of labeled sterol was biphasic. There were no differences in vivo plasma cholesterol ester metabolism, elimination kinetics, or fecal elimination rate for labeled sterol from [3H]cholesteryl palmitate or [14C]cholesteryl palmitoleate within CPFA or control groups. However, compared to controls, CPFA animals diverted significantly more labeled sterol into saturated and diunsaturated cholesterol esters, less into mono- and tetraunsaturated esters, and showed decreased blood clearance and fecal elimination of labeled sterol. Biliary elimination was probably not impaired by depressed hepatic cholesterol esterase activity in CPFA-fed mice. The fundamental effect of CPFA on serum cholesterol concentration appears to reside in a severely imbalanced cholesterol ester profile. Results indicate that CPFA alter normal fatty acid profile of serum cholesterol esters by proportionally altering the C-2 fatty acyl composition of serum phospholipid, which is the substrate for lecithin:cholesterol acyltransferase, the major source of plasma cholesterol esters.

Aflatoxicol (AFL), a major metabolite of aflatoxin B1 (AFB1) in the Mt. Shasta rainbow trout (Salmo gairdneri), was found to produce hepatocellular carcinoma in trout. It was administered in a casein diet to duplicate groups of 120 fingering trout. In the same manner, additional duplicate groups received one of the following: no toxicant; AFB1; the diastereomer of AFL (AFL'); cyclopropenoid fatty acids (CPFA); and CPFA plus AFB1, AFL, and AFL'. Eight months after the initiation of the study, the following incidences of carcinoma were observed: control (0%); 20 ppb AFB1 (56%); 29 ppb AFL (26%); 61 ppb AFL' (0%); 50 ppm CPFA (3%); 20 ppb AFB1 plus 50 ppm CPFA (96%); 29 ppb AFL plus 50 ppm CPFA (94%); and 61 ppb AFL' plus 50 ppm CPFA (55%), showing both the carcinogenicity of AFL and the synergistic effects of CPFA. Twelve-month incidences were correspondingly higher in all cases. Aflatoxin M1, another metabolite of AFB1 in rainbow trout, was reported previously to be carcinogenic in trout. These results support the hypothesis that metabolism in rainbow trout does not effectively detoxify AFB1, but rather the formation of AFL extends the carcinogenicity of AFB1 and may contribute to the high sensitivity of rainbow trout to AFB.

Isolated hepatocytes from rainbow trout readily activated aflatoxin B1 (AFB1) to mutagens detectable by S. typhimurium TA 98. Characterization studies demonstrated that activation efficiency was essentially linear with respect to hepatocyte concentration (5 X 10(5)-2 X 10(7) cell/ml) and AFB1 dose (0-10 micrograms/ml). This system was employed to assess possible differences in AFB1 activation in hepatocytes from rainbow trout and coho salmon, two species which have been shown in in vivo studies to differ widely in sensitivity to AFB1 carcinogenesis. Activation efficiency was approximately three times greater in trout hepatocytes compared with salmon hepatocytes. This difference was more marked when S20 liver fractions from the two species were used. Analysis of unbound [3H]AFB1 metabolites performed on supernatants of hepatocyte incubations revealed that under the normal conditions of assay, addition of bacteria does not perturb the various pathways of AFB1 metabolism within hepatocytes. These results support other studies which suggest that the greater sensitivity of trout to AFB1 carcinogenicity resides largely in increased initial DNA damage, compared with coho salmon.

The formation of covalent aflatoxin-DNA adducts has been studied in embryo and yearling stages of the rainbow trout (Salmo gairdneri). A linear relationship was found between the amount of aflatoxin B1 (AFB1) absorbed into 21-day-old eggs and the level of covalent modification of embryo DNA after exposure to 0.25 to 0.5 p.p.m. aqueous solutions of AFB1 for 1 h; higher concentrations resulted in absorption of a greater proportion of AFB1. The principal covalent product, identified after acid and enzymatic hydrolysis of isolated embryo DNA, was chromatographically identical to 2,3-dihydro-2-(N7-guanyl)-3-hydroxy aflatoxin B1. Additional AFB1 derivatives which were present are believed to be formed by chemical transformation of this product in DNA producing an aflatoxin-formamidopyrimidine adduct and the metabolic activation of other aflatoxin metabolites, such as aflatoxin M1 and aflatoxin P1. Although the eggs were exposed to AFB1 for a short time, covalent modification of DNA was evident over an extended period. The highest level of covalent products was present at approximately 24 h after exposure to 0.5 p.p.m. AFB1. Ninety-six hours later, this level had decreased slightly; however, the distribution of covalent adducts had changed: formamidopyrimidine adducts now represented up to 50% of the hydrolyzed aflatoxin derivatives. A similar pattern of covalent aflatoxin derivatives was found in the liver DNA of yearling trout 10 h after the administration of 0.3 mg/kg AFB1.

beta-Naphthoflavone (beta NF) fed to rainbow trout (Salmo gairdneri) at 50 or 500 ppm in the diet, modified the in vitro metabolism of aflatoxin B1 (AFB1) by the postmitochondrial fraction (PMF) of the liver. Production of aflatoxicol (AFL) was significantly less in the 500 ppm beta NF-fed group (33.9 ng/mg protein) than in the control group (45.7 ng/mg protein), aflatoxin M1 production was dependent on the dose of beta NF, being greatest in the 500 ppm beta NF-fed group (48.9 ng/mg protein), intermediate in the 50 ppm beta NF-fed group (3.7 ng/mg protein), and was not detected in controls. A new trout metabolite, 4-hydroxyaflatoxicol (aflatoxicol M1, AFLM1) was also detected in small amounts from in vitro metabolism by liver PMF from beta NF-fed trout. Sufficient quantities of AFLM1 for confirmation of identity by ultraviolet spectra, mass spectra and nuclear magnetic resonance spectra were prepared by biotransformation of AFL using liver microsomes and isolation by HPLC. In a modified Ames mutagen assay with Salmonella typhimurium TA98, ALFM1 was 4.1% as mutagenic as AFB1 in a previous determination. The carcinogenicity of AFLM1 to rainbow trout is expected to be considerably less than that of AFB1.

The degenerative changes of the lumbar spine in 100 patients with symptomatic low-back pain were reviewed using plain roentgenograms and computed tomographic scans in order to determine the relationship between degeneration and annular protrusion. Additionally, the lumbar spinal units of 25 fresh cadavers were roentgenographed, injected with a mixture of methylene blue and renografin-60, dissected, and studied. The state of degeneration of each of the intervertebral units of both groups was graded on a four-point scale based on the roentgenographic presence or absence of osteophytes and facet joint changes, and the intervertebral disc height. The degree of annular protrusion was measured by dividing the anteroposterior diameter of the intervertebral disc by the anteroposterior diameter of the vertebral plate as determined on the radiographic studies. In the clinical group, 39 intervertebral discs having Grade II and III degeneration exhibited a statistically higher annular/vertebral diameter ratio (A/V index) of 1.30 as compared to the normal invertebral discs, with an A/V index of 1.12 (P less than 0.001). The dissection of the disc spaces of the cadavers with radiographic evidence of disc space narrowing and marginal osteophytosis, Grade II and III degeneration, displayed significant interruption and tearing of the annular fibers and peripheral migration of collagenized nuclear fragments. In both the clinical and pathologic groups, there was a direct correlation between the size of the annular bulge, as indicated in the A/V index, and the degree of narrowing of the disc space. Therefore, this study indicated that annular protrusion is an intricate part of the degeneration process.

Rainbow trout (Salmo gairdneri) were fed a control diet with or without an antioxidant--3,5-di-tert-butyl-4-hydroxytoluene (BHT), 2(3)-tert-butyl-4-hydroxyanisole (BHA), mono-tert-butylhydroquinone (TBHQ) or ethoxyquin (EQ)--at a level of 5.56 mmol in 100 g oil/kg diet for 6 wk. The treated trout had reduced liver weight/body weight ratios. In comparison with trout fed control diet, microsomal protein content was lowered by 13% in TBQH-fed trout and elevated by 28% in EQ-fed trout, cytochrome P-450 content was 21% lower in BHA- and TBHQ-fed and 18% lower in EQ-fed trout and cytochrome b5 content was 46% lower in EQ-fed trout. Activities of benzo[a]pyrene hydroxylase, epoxide hydratase and ethoxycoumarin-O-deethylase were, respectively, 3.2-4.8, 1.2-1.7 and 1.3-5.5 times higher in antioxidant-fed trout. NADPH-cytochrome c reductase was elevated 1.2-1.3 times over the control value with dietary BHA, TBHQ and BHT, but was lowered with EQ. p-Nitroanisole-O-demethylase activity was completely suppressed in antioxidant-fed trout. The content of post-mitochondrial acid-soluble sulphydryl groups was 42% lower in BHA- and BHT-fed trout. Alterations in the enzyme activities of the mixed-function oxidase system, changes in the ethyl isocyanide binding ratio and decreases in cytochrome P-450 content suggest that dietary antioxidants could alter carcinogen activation and/or detoxification mechanisms in the hepatic microsomes of rainbow trout.

Male New Zealand weanling rabbits were fed a diet containing 0.25% cyclopropenoid fatty acids for 28 days. Compared with the controls, the rabbits given cyclopropenoid fatty acids showed retarded growth, some moderate liver histological damage, altered hepatic mixed-function-oxidase activities and minor variations in vitro [14C]aflatoxin B1 metabolism. In in vitro assays the major hepatic metabolite of aflatoxin B1 (AFB1) was aflatoxicol (AFL) and the major AFL metabolite was AFB1. Minor amounts of aflatoxin M1 and a metabolite believed to be AFL-M1 were formed. The similarity of this AFB1 metabolite pattern to that in rainbow trout, taken together with the apparent absence of AFB1 detoxification products is consistent with the sensitivity of both species to the acute effects of AFB1.

Rainbow trout were fed diets containing 3.4 mmol of indole-3-carbinol, indole-3-ethanol, indole-3-aldehyde, or indole-3-acetic acid in 100 g salmon oil/kg diet for 3 weeks. The indoles did not increase hepatic microsomal cytochrome(s) P-450 or P-448 nor induce the associated mixed function oxidase enzyme activities as measured by ethoxyresorufin-O-deethylase (EROD) and benzphetamine-N-demethylase activities. Indole-3-carbinol did not alter the in vitro metabolism of aflatoxin B1 to aflatoxicol and aflatoxin M1; but the other indoles did suppress the formation of aflatoxin M1 from aflatoxin B1. The results suggest that the mechanism by which indole-3-carbinol protected rainbow trout from aflatoxin B1 (AFB1) hepatocarcinogenesis was not via the alteration of the mixed function oxidase system.

Rainbow trout embryos are sensitive to the initiation of neoplasms in various tissues by brief exposures to solutions of water-soluble carcinogens. This characteristic was first demonstrated with the sparingly soluble liver carcinogen, aflatoxin B1 (AFB1). A 30-minute exposure of 21-day-old embryos (embryos hatch in 24-25 days at 12 degrees C) to a 0.5-ppm aqueous solution of AFB1 will result in approximately 65 of the survivors having at least 1 liver tumor, 1 year after treatment. The embryos are responsive to both AFB1 dose and the length of exposure and become increasingly sensitive with increased embryonic age. We have used rainbow trout embryos to demonstrate the hepatocarcinogenicity of other aflatoxin metabolites and precursors; aflatoxicol, aflatoxin G1, versicolorin A, and sterigmatocystin. In addition to mycotoxins, trout embryos are sensitive to several nitrosamine hepatocarcinogens including: dimethylnitrosamine, diethylnitrosamine, nitrosopyrrolidine, and 2,6-dimethylnitrosomorpholine. However, with the highly water-soluble nitrosamines, longer exposure time (up to 24 hr) are required. It is generally accepted that each of the above-named carcinogens requires metabolic activation to the ultimate carcinogenic form. This provides indirect evidence that the trout embryo is capable of cytochrome P-450-mediated metabolism. Finally, trout embryos are sensitive to the direct-acting carcinogen, N-methyl-N'-nitro-N-nitrosoguanidine. This compound produces tumors of the liver, stomach, kidney, and swim bladder, and a pronounced female-to-male sex reversal. Results to date have shown that the trout embryo is a sensitive, convenient, and economical whole animal model system with many distinct advantages for carcinogen testing and research.(ABSTRACT TRUNCATED AT 250 WORDS)

In general, injuries to dancers involving the cervical spine and upper extremities are quite mild and cause only limited disability. When such injuries do not involve specific elements of the musculoskeletal system, their origin may be in the more subtle neurovascular structures of the neck. The importance of a thorough examination is emphasized.

A modification of the Ames assay using rainbow trout (Salmo gairdneri) liver postmitochondrial fraction (PMF) was developed to investigate the relative mutagenic potential of a series of aflatoxins (AFs). Preliminary experiments revealed that the 20000 x g (S20) liver fraction contained a higher metabolic activity than either the S9 or S30 fractions, and that 5 mg of S20 protein/plate gave the highest mutagenic response. A 9-24 h preincubation period at 25 degrees C was also required. The results from comparative mutagenicity experiments showed the following relative potencies: AFB1 greater than AFL greater than AFG1 greater than AFM1 greater than AFB2 greater than AFP1 greater than AFQ1. The relative potencies observed with this in vitro system qualitatively correlated with the in vivo carcinogenic activity seen in trout, indicating that this assay is of value in predicting the carcinogenic potential of mycotoxins in this species.