Review: When worlds collide - poultry modeling in the 'Big Data' era

Within poultry production systems, models have provided vital decision support, opportunity analysis, and performance optimization capabilities to nutritionists and producers for decades. In recent years, due to the advancement of digital and sensor technologies, 'Big Data' streams have emerged, optimally positioned to be analyzed by machine-learning (ML) modeling approaches, with strengths in forecasting and prediction. This review explores the evolution of empirical and mechanistic models in poultry production systems, and how these models may interact with new digital tools and technologies. This review will also examine the emergence of ML and Big Data in the poultry production sector, and the emergence of precision feeding and automation of poultry production systems. There are several promising directions for the field, including: (1) application of Big Data analytics (e.g., sensor-based technologies, precision feeding systems) and ML methodologies (e.g., unsupervised and supervised learning algorithms) to feed more precisely to production targets given a 'known' individual animal, and (2) combination and hybridization of data-driven and mechanistic modeling approaches to bridge decision support with improved forecasting capabilities.

Productive performance of beef cows subjected to different nutritional levels in the third trimester of gestation

In general, calf production occurs in less intensive systems. The limitation of nutrients during the gestation phase of beef cows can have negative impacts on the consequent productivity of females. Therefore, this study aimed to evaluate the effects of nutritional levels in the third trimester of pregnancy on the productive performance of beef cows kept in a natural pasture (NP). Eighty-three Charolais × Nelore cows were used, ranging in age from 4 to 12 years, which were divided according to their nutritional levels during the third trimester of pregnancy: NP, cows supplemented with 100% of their energy and protein requirements (SP100) and cows supplemented with 150% of their energy and protein requirements (SP150). The experimental design was completely randomized with three treatments and a varied number of repetitions. The SP100 and SP150 cows presented better body condition at calving (2.92 and 2.99 vs 2.81 points) and at the start of the breeding season (2.90 and 2.95 vs 2.80 points) than did NP cows. The nutritional level of the cows in the third trimester of gestation did not influence the blood metabolite concentrations. The plasma levels of albumin and total proteins were 3.11 and 8.18 g/dl, respectively. Glucose and cholesterol showed values of 74.96 and 166.50 mg/dl. The lowest concentration of blood metabolites was observed in the first postpartum weeks. The SP100 and SP150 cows showed faster follicular growth and, consequently, a higher percentage of females with ovulatory follicles at 21 days postpartum than did NP cows (45.68, 41.11, and 11.00%, respectively). The SP150 cows had a higher pregnancy rate (40.74%), total calf production (295.88 kg/cow), and consequently, offspring sale value. An increased nutritional level in the third trimester of pregnancy improves the postpartum metabolic condition and productive efficiency of beef cows kept on NP.

Illuminating gravitational waves: A concordant picture of photons from a neutron star merger

Merging neutron stars offer an excellent laboratory for simultaneously studying strong-field gravity and matter in extreme environments. We establish the physical association of an electromagnetic counterpart (EM170817) with gravitational waves (GW170817) detected from merging neutron stars. By synthesizing a panchromatic data set, we demonstrate that merging neutron stars are a long-sought production site forging heavy elements by r-process nucleosynthesis. The weak gamma rays seen in EM170817 are dissimilar to classical short gamma-ray bursts with ultrarelativistic jets. Instead, we suggest that breakout of a wide-angle, mildly relativistic cocoon engulfing the jet explains the low-luminosity gamma rays, the high-luminosity ultraviolet-optical-infrared, and the delayed radio and x-ray emission. We posit that all neutron star mergers may lead to a wide-angle cocoon breakout, sometimes accompanied by a successful jet and sometimes by a choked jet.

Characterizing defects and transport in Si nanowire devices using Kelvin probe force microscopy

Si nanowires (NWs) integrated in a field effect transistor device structure are characterized using scanning electron (SEM), atomic force, and scanning Kelvin probe force (KPFM) microscopy. Reactive ion etching (RIE) and vapor-liquid-solid (VLS) growth were used to fabricate NWs between predefined electrodes. Characterization of Si NWs identified defects and/or impurities that affect the surface electronic structure. RIE NWs have defects that both SEM and KPFM analysis associate with a surface contaminant as well as defects that have a voltage dependent response indicating impurity states in the energy bandgap. In the case of VLS NWs, even after aqua regia, Au impurity levels are found to induce impurity states in the bandgap. KPFM data, when normalized to the oxide-capacitance response, also identify a subset of VLS NWs with poor electrical contact due to nanogaps and short circuits when NWs cross that is not observed in AFM images or in current-voltage measurements when NWs are connected in parallel across electrodes. The experiments and analysis presented outline a systematic method for characterizing a broad array of nanoscale systems under device operation conditions.

Design of a versatile chemical assembly method for patterning colloidal nanoparticles

Poly(methyl methacrylate) (PMMA) domains in phase-separated polystyrene-b-poly(methyl methacrylate) (PS-b-PMMA) diblock copolymer thin films were chemically modified for controlled placement of solution synthesized Au nanoparticles having a mean diameter of 24 nm. Colloidal Au nanoparticles functionalized with thioctic acid were immobilized on amine functionalized PMMA domains on the PS-b-PMMA template using 1-ethyl-3-[3-dimethylaminopropyl] carbodiimide hydrochloride linking chemistry and N-hydroxy sulfosuccinimide stabilizer. Atomic force microscopy and scanning electron microscopy images demonstrated immobilization of Au nanoparticles commensurate with PMMA domains. Nanoparticles form into clusters of single particles, dimers, and linear chains as directed by the PMMA domain size and shape. Capillary forces influence the spacing between Au nanoparticles on PMMA domains. Inter-particle spacings below 3 nm were achieved and these assemblies of closely spaced nanoparticle clusters are expected to exhibit strong localized electromagnetic fields. Thus, these processes and material systems provide an experimental platform for studying resonantly enhanced excitations of surface plasmons as a function of material and geometric structure as well as utilization in catalytic applications.

What affects the age of first sleeping through the night?

OBJECTIVE

To ascertain the age at which an infant first sleeps regularly through the night and the factors affecting this age.

METHODS

A representative cross sectional sample of 700 infants in south-east England were studied. Information was collected on 511 (73.0%) of the infants by parental interview. Obstetric records were also examined.

RESULTS

Fifty per cent of babies slept through by 8 weeks and 75% by 12 weeks. Multivariate survival analysis used to investigate 61 potential factors found that a heavier birthweight, female gender and co-sleeping less than 2 hours or not at all; younger mothers, school leaving age less than 17 years, stress factors (divorce and no separation from partner for more than a month in the last 12 months); no central heating, and the baby not sharing a room with siblings were associated with an earlier age at which an infant first sleeps through the night.

CONCLUSIONS

Little of the variation between children in age of first sleeping through the night could be explained by these nine factors.

Increasing the efficiency of pharmacokinetic sample procurement, preparation and analysis by liquid chromatography/tandem mass spectrometry

The movement towards a 96-well format has greatly increased productivity and throughput in bioanalytical laboratories. Improvements in automated sample preparation and analytical methods have further contributed to increased productivity. We have focused on sample collection and transfer to the bioanalyst and have found improvements to the current available methods. The problem of manual transfers and plasma clotting issues can be overcome with the use of microtainers. Specifically, for illustrative purposes, three proprietary Theravance compounds were tested for stability, non-specific binding, and electrospray ion suppression in microtainers. There were no issues with stability, non-specific binding or ion suppression for the above compounds even after leaving plasma samples in the microtainers over long periods of time. The microtainers are robot-compatible and the resulting plasma can be transferred without clotting issues. To date, all in-house compounds successfully analyzed and tested using the microtainers have mass ranges between 200 and 1800 Da, pK(a) ranges between 3.8 and 10.3, and logD ranges between -1.7 and 4.2. Once samples are transferred into 96-well plates, flexibility in preparation and analysis is available. Together with automated sample preparation and the use of liquid chromatography/tandem mass spectrometry (LC/MS/MS) as an analytical tool, the use of microtainers as sample collection tubes and for sample storage saved considerable time, cost and effort in both of our pharmacokinetic (PK) and bioanalytical groups. This in turn has led to an increased efficiency and overall throughput in support of our drug discovery effort.

Changes in oviductal morphology of the skink,Lampropholis guichenoti, associated with egg production

We describe changes in the morphology of the oviductal epithelium of an oviparous skink, Lampropholis guichenoti, during the course of egg production and oviposition: to characterize the luminal epithelial changes; to provide a baseline for understanding uterine changes in viviparous species; and to establish whether the plasma membrane transformation of uterine epithelial cells is indeed a feature restricted to viviparous species. Oviducts from vitellogenic, gravid, and postgravid females were observed using scanning electron microscopy. Cellular characteristics of the oviductal epithelium previously used to determine the plasma membrane transformation were assessed morphologically. Three anatomically different areas were defined within the oviduct, but no plasma membrane transformation was observed in the oviparous skink, suggesting that this is a phenomenon particular to viviparity.

Hydrophobic Vancomycin Derivatives with Improved ADME Properties: Discovery of Telavancin (TD-6424)

Novel derivatives of N-decylaminoethylvancomycin (2), containing appended hydrophilic groups were synthesized and their antibacterial activity and ADME properties were evaluated. The compounds were prepared by reacting amines with the C-terminus (C-) of 2 using PyBOP mediated amide formation, or with the resorcinol-like (R-) position of 2 using a Mannich aminomethylation reaction. These analogs retained the antibacterial activity of 2 against methicillin-resistant staphylococci and vancomycin-resistant enterococci. Compounds with a negatively charged auxiliary group also exhibited improved ADME properties relative to 2. In particular, R-phosphonomethylaminomethyl derivative 21 displayed good in vitro antibacterial activity, high urinary recovery and low distribution to liver and kidney tissues. Based on these results, 21 was advanced into development as TD-6424, and is currently in human clinical trials. The generic name telavancin has recently been approved for compound 21.

Human uterodomes (pinopods) do not display pinocytotic function

BACKGROUND

The term 'pinopod' or 'pinopode' has been used indiscriminately since the 1970s to describe most apical structures on uterine epithelial cells and as such suggests a cross species structural functionality. This study looks at the apical cellular protrusions in rats and humans and compares their pinocytotic ability.

METHODS

We have utilized standard tracer techniques in an attempt to determine the functionality of the uterine surface protrusions in the human based on results reported in rats.

RESULTS

Pinopods in rat tissue demonstrated tracer uptake, but no tracer uptake in the apical protrusions of human uterine epithelium was evident.

CONCLUSIONS

These findings indicate that the uterine surface protrusions observed in the human are not pinocytotic and therefore probably perform a function different from similar structures observed in rats and mice. This highlights the need to alter nomenclature from pinopods to uterodomes.

Clinical features and mutations in patients with dominant retinitis pigmentosa-1 (RP1)

PURPOSE

To survey patients with dominant retinitis pigmentosa (RP) for mutations in the RP1 gene to determine the spectrum of dominant mutations in this gene, to estimate the proportion of dominant RP caused by this gene, and to determine whether the clinical features of patients with RP1 mutations differ from features of those with rhodopsin mutations.

METHODS

A set of 241 patients who did not have mutations in the rhodopsin gene (based on previous work) formed the basis for the study. Of these patients, 117 had also been previously evaluated and were found not to carry mutations in the RDS gene. The single-strand conformation polymorphism (SSCP) method was used to search for sequence variants, which were then directly sequenced. The relatives of selected patients were recruited for segregation analyses. Clinical evaluations of patients included a measurement of Snellen visual acuity, final dark adaptation thresholds, visual fields, and ERGs. Clinical data were compared with those obtained earlier from a study of 128 patients with dominant rhodopsin mutations.

RESULTS

Of the 241 patients, all were screened for the most common RP1 mutation (Arg677Ter), and 10 patients were found to have this mutation. In addition, an evaluation of a subset of 189 patients in whom the entire coding sequence was evaluated revealed the following mutations: Gln679Ter (1 case), Gly723Ter (2 cases), Glu729(1-bp del) (1 case), Leu762(5-bp del) (2 cases), and Asn763(4-bp del) (1 case). All of these mutations cosegregated with RP in the families of the index patients. Nine missense mutations that were each found in six or fewer patients were encountered. The segregation of eight of these was evaluated in the respective patients' families, and only one segregated with dominant RP. This cosegregating missense change was in cis with the nonsense mutation Gln679Ter. Although patients with RP1 mutations had, on average, slightly better visual acuity than patients with rhodopsin mutations, there was no statistically significant difference in final dark-adaptation thresholds, visual field diameters, or cone electroretinogram (ERG) amplitudes. Comparably aged patients with RP1 mutations had visual function that varied by approximately two orders of magnitude, based on visual fields and ERG amplitudes.

CONCLUSIONS

Dominant RP1 alleles typically have premature nonsense codons occurring in the last exon of the gene and would be expected to encode mutant proteins that are only approximately one third the size of the wild-type protein, suggesting that a dominant negative effect rather than haploinsufficiency is the mechanism leading to RP caused by RP1 mutations. On average, patients with RP1 mutations have slightly better visual acuity than patients with dominant rhodopsin mutations; otherwise, they have similarly severe disease. The wide range in severity among patients with RP1 mutations indicates that other genetic or environmental factors modulate the effect of the primary mutation.

Null RPGRIP1 alleles in patients with Leber congenital amaurosis

We isolated and characterized the entire coding sequence of a human gene encoding a protein that interacts with RPGR, a protein that is absent or mutant in many cases of X-linked retinitis pigmentosa. The newly identified gene, called "RPGRIP1" for RPGR-interacting protein (MIM 605446), is located within 14q11, and it encodes a protein predicted to contain 1,259 amino acids. Previously published work showed that both proteins, RPGR and RPGRIP1, are present in the ciliary structure that connects the inner and outer segments of rod and cone photoreceptors. We surveyed 57 unrelated patients who had Leber congenital amaurosis for mutations in RPGRIP1 and found recessive mutations involving both RPGRIP1 alleles in 3 (6%) patients. The mutations all create premature termination codons and are likely to be null alleles. Patients with RPGRIP1 mutations have a degeneration of both rod and cone photoreceptors, and, early in life, they experience a severe loss of central acuity, which leads to nystagmus.

Mental Health Disaster Response: Nursing Interventions Across the Life Span

In the aftermath of a natural disaster, adult survivors often move through the following phases of disaster response: Heroic Phase, Honeymoon Phase, Disillusionment Phase, and Reconstruction Phase. Understanding age-related responses to traumatic events such as a tornado enables mental health clinicians to individualize appropriate interventions and prevent or diminish emotional sequelae such as post-traumatic stress disorders. Psychiatric-mental health nurses are encouraged to attend local Red Cross disaster training to be prepared should the need arise for mobilization of mental health disaster response teams in your community.

Effect of age, breed and dietary omega-6 (n-6): omega-3 (n-3) fatty acid ratio on immune function, eicosanoid production, and lipid peroxidation in young and aged dogs

The focus of this study was to examine the influence of age and diet on various parameters of immune function in young and old Fox Terriers and Labrador Retrievers. Eighteen young and old dogs were utilized for this study. Young and old dogs were fed a basal diet containing an (n-6):(n-3) ratio of 25:1 for sixty days (Phase I). Half of the dogs were then switched to a diet with an (n-6):(n-3) ratio of 5:1, and all were maintained on their respective diets for an additional sixty days (Phase II). Results from these studies revealed an age-associated decline in several immune parameters measured. Both these breeds demonstrated a reduction in sheep red blood cell titers, as well as in their ability to respond to different mitogens. Interestingly, this decline was greater in Fox Terriers, suggesting a decrease in cellular proliferative capacity in lymphocytes isolated from the larger breed. Neither cytokine production or DTH response was affected by age. Diet and breed interactions resulted in a significant increase in T- and B-cell mitogen responsiveness. In contrast, supplementation with n-3 fatty acids did not affect IL-1, IL-6 or TNF-alpha production. Supplementation with n-3 fatty acids resulted in increased PGE3 production from peritoneal macrophages but had no effect on PGE2 production from peripheral blood mononuclear cells or peritoneal macrophages. The n-3 fatty acid supplementation did not influence alpha-tocopherol status although older dogs had significantly lower serum alpha-tocopherol concentrations. Oxidative status of these dogs was assessed by serum levels of malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE). Feeding an n-3-enriched diet did not affect 4-HNE levels but significantly decreased MDA levels in old dogs. In summary, this study indicates that feeding a diet containing an (n-6):(n-3) fatty acid ratio of 5:1 had a positive, rather than a negative, effect on the immune response of young or geriatric dogs.

Hope: The Critical Factor in Recovery

1. Psychiatric rehabilitation focuses on improving a person's knowledge and skills to maximize levels of functioning and developing resources within the community to support successful living. 2. The recovery process is a lifelong process of defining new possibilities and finding new meaning and purpose in life. By accepting the limitations of what they cannot do, clients begin to discover what they are able to do and to look forward to a new beginning. 3. Facilitating success, connecting to successful role models, managing the illness, and educating clients and the community are all identified as areas that enhance hope for clients.

Integrating Psychosocial Rehabilitation in a Community-Based Faculty Nursing Practice

1. When clients share their experiences with students, the experience helps sensitize students to the stigma of mental illness, and also facilitates the client's recovery. 2. Encouragement from staff, clinicians, other clients, and family members that they can succeed at this next step in what most often motivates a client-consumer to "try" something new or "try again". 3. Client involvement in community activities is effective in normalizing daily life experiences and in breaking down the barrier of stigma.

SPECIAL SECTION: Perspectives of the Scientific Community on the Status of Ecological Risk Assessment

/ Views from a wide variety of practicing environmental professionals on the current status of ecological risk assessment (ERA) indicate consensus and divergence of opinion on the utility and practice of risk assessment. Central to the debate were the issues of whether ERA appropriately incorporates ecological and scientific principle into its conceptual paradigm. Advocates argue that ERA effectively does both, noting that much of the fault detractors find with the process has more to do with its practice than its purpose. Critics argue that failure to validate ERA predictions and the tendency to over-simplify ecological principles compromise the integrity of ERA and may lead to misleading advice on the appropriate responses to environmental problems. All authors felt that many improvements could be made, including validation, better definition of the ecological questions and boundaries of ERA, improved harmonization of selected methods, and improvements in the knowledge base. Despite identified deficiencies, most authors felt that ERA was a useful process undergoing evolutionary changes that will inevitably determine the range of environmental problems to which it can be appropriately applied. The views expressed give ERA a cautious vote of approval and highlight many of the critical strengths and weaknesses in one of our most important environmental assessment tools.KEY WORDS: Ecological risk assessment; Ecology; Probability

Application of multiple bioindicators to differentiate spatial and temporal variability from the effects of contaminant exposure on fish

Bioindicators of fish health were measured from 1989 through 1994 in populations of redbreast sunfish (Lepomis auritus) at three sites within a stream receiving inputs of mixed contaminants from an industrial facility, and at two reference sites. Bioindicator responses differed for fish from contaminated and reference sites throughout the study period, but temporal trends at contaminated sites reflected improved water quality associated with pollution-control efforts. Temporal variability unrelated to contaminant exposure strongly influenced the response of bioindicators at both reference and contaminated sites, but spatial variability rarely influenced these responses. Temporal variability was less influential on slower responding indicators at higher levels of biological organization. The diverse response characteristics of indicators increased the ability to differentiate natural from anthropogenic sources of variability. Integrated bioindicator responses were compared among site-year groups by multivariate canonical analysis. The primary canonical variable, associated with differences in growth, exhibited trends consistent with the timing of pollution-control efforts. Two indicators of contaminant exposure (7-ethoxyresorufin O-deethylase activity and polychlorinated biphenyls in fish muscle) also exhibited trends consistent with the timing of pollution-control efforts, but the likelihood of possible mechanistic linkages cannot be assessed with available data.

Innate immune function as a bioindicator of pollution stress in fish

Immunotoxicological studies, based on processing of samples in the field and laboratory, were conducted on fish collected from a stream receiving point-source contaminants near its headwaters. Previous studies in this stream have revealed that cytochrome P4501A activity, liver somatic indices, macrophage aggregates, and parasitic liver lesions are significantly elevated in sunfish with the degree of impact decreasing with distance from the contaminant source. Fish collected from each sampling site were equally divided, One group was sacrificed in the field and the spleen and anterior kidney tissues were removed and placed in buffer on ice. The other group was kept in MS-222 for 2 hr and transported to the laboratory for processing. The spleen and anterior kidney from each fish were then prepared as a single cell suspension and shipped overnight to Mississippi State University. Cells were then evaluated for PMA-stimulated phagocyte oxidative burst and non-specific cytotoxic cell (NCC) activity against K562 tumor targets. Oxidative burst responses were dramatically suppressed in both groups at sampling sites near the headwaters but returned to reference levels further downstream. There were no differences between processing strategies at each station. NCC activities did not follow gradient-response patterns observed with phagocyte oxidative burst data and there were inconsistent differences between processing strategies at each site. These data indicate that simple immune function assays, such as phagocyte oxidative burst responses, can be used as a ancillary bioindicator in fish health monitoring and that immune function in these fish can be reliably assessed even if samples are not immediately processed.

The Drosophila melanogaster homologue of the human BBC1 gene is highly expressed during embryogenesis

We have previously reported the isolation and preliminary characterisation of a full-length cDNA sequence derived from the human BBC1 gene, a gene which displays differential expression in tumours of the female breast [Adams et al., Hum. Mol. Genet. 1 (1992) 91-96]. Here, we report the isolation and characterisation of the Drosophila melanogaster (Dm) homologue of this human gene. The Dmbbc1 cDNA is 62% identical to the human BBC1 cDNA within a conserved open reading frame and the encoded proteins share 74% sequence similarity. The Dmbbc1 mRNA is expressed at all stages of Dm development, with the highest levels of expression occurring during embryogenesis. In addition, the Dm and human BBC1 proteins share remarkable degrees of identity with the products of recently isolated plant and avian bbc1 cDNAs. The sequences of all the predicted BBC1 proteins are highly similar to that of the rat ribosomal subunit protein L13 [Olvera and Wool, Biochem. Biophys. Res. Commun. 201 (1994) 102-107], strongly indicating that the BBC1 protein is ribosomal protein L13.

Differential expression of the mitochondrial gene cytochrome oxidase II in benign and malignant breast tissue

Comparative analysis of expression levels of genes in benign and malignant tumours of the breast has been performed. Differential screening of cDNA libraries identified four genes of the mitochondrial genome as being expressed at different levels in the two tissues compared, but further investigations showed that only the gene encoding subunit 2 of cytochrome c oxidase (COII) is expressed at significantly higher levels in carcinomas compared with fibroadenomas. The mitochondrial genes encoding subunits 2 and 4 of NADH dehydrogenase, and subunit 6 of F0F1ATPase, were not found to be differentially expressed in carcinomas and fibroadenomas. All four genes were expressed in the epithelium of human breast carcinomas, as shown by in situ hybridization. The expression level of the COII gene is also correlated with carcinoma grade. No gross alterations to the mitochondrial DNA from these tumours could be detected. The possible implications of these results on the behavioural differences between fibroadenomas and carcinomas are discussed.

Isolation and characterization of a novel gene with differential expression in benign and malignant human breast tumours

We report the identification of a novel cDNA representing an mRNA showing significantly higher levels of expression in benign breast lesions than in carcinomas. This cDNA was identified by differential screening of a cDNA library generated from a breast carcinoma, and shows consistently higher expression in fibroadenomas than in carcinomas. The expression in both benign and malignant tissues is highest in epithelial cells as determined by in situ hybridization to tissue sections. The nucleotide sequence of the full-length cDNA has been determined, and the deduced protein is highly basic with no signal or transmembrane sequence, but two potential nuclear localization signals. Neither the DNA nor the protein sequence show any significant homology to sequences in current databases. The cDNA hybridizes to multiple sequences within both human and other mammalian genomes, but to single genomic sequences in Drosophila, Physarum and Schizosaccharomyces pombe. This cDNA therefore represents a highly conserved gene sequence. We have identified only one major transcript in human cells, and it seems likely that there are several pseudogenes within the human genome.

Differential expression of translation-associated genes in benign and malignant human breast tumours

The human gene sequences encoding the translation-associated functions of alpha-subunit of elongation factor 1 (EF-1 alpha) and the ubiquitin carboxyl extension protein (HUBCEP80) have been isolated by differential cDNA screening, and found to have significantly higher levels of expression in fibroadenomas (benign) compared with carcinomas (malignant) of the breast. These data parallel our previous findings that the acidic ribosomal phosphoprotein P2 also has higher expression levels in the benign breast tumours (Sharp et al., 1990). In situ hybridisation has shown these genes to be expressed predominantly in the epithelium of breast tumours.

Genetic organization of the KpnI restriction--modification system

The KpnI restriction-modification (KpnI RM) system was previously cloned and expressed in E. coli. The nucleotide sequences of the KpnI endonuclease (R.KpnI) and methylase (M. KpnI) genes have now been determined. The sequence of the amino acid residues predicted from the endonuclease gene DNA sequence and the sequence of the first 12 NH2-terminal amino acids determined from the purified endonuclease protein were identical. The kpnIR gene specifies a protein of 218 amino acids (MW: 25,115), while the kpnIM gene codes for a protein of 417 amino acids (MW: 47,582). The two genes transcribe divergently with a intergeneic region of 167 nucleotides containing the putative promoter regions for both genes. No protein sequence similarity was detected between R.KpnI and M.KpnI. Comparison of the amino acid sequence of M.KpnI with sequences of various methylases revealed a significant homology to N6-adenine methylases, a partial homology to N4-cytosine methylases, and no homology to C5-methylases.

A sequence previously identified as metastasis-related encodes an acidic ribosomal phosphoprotein, P2

We have used a metastasis-related human cDNA isolated from a liver metastasis from a colonic adenocarcinoma to screen a human breast carcinoma cDNA library for homologous sequences. Nucleotide sequence analysis of positive clones revealed that the cDNA represents a ribosomal phosphoprotein. P2. The expression of P2 mRNA was significantly higher (Student's t test, one tail; P less than or equal to 0.01) in seven fibroadenomas than in seven carcinomas, with an average five-fold difference. This enhanced expression level P2 mRNA in benign fibroadenomas compared with malignant carcinomas is contrary to that expected, based on earlier work with normal colonic mucosa, colorectal carcinoma and hepatic metastasis. The identification of gene transcripts which differ in abundance and correlate with the metastatic phenotype may be of considerable importance both as diagnostic aids and in defining the changes associated with tumour progression and metastasis at the molecular level. The possible role that ribosomal proteins may play in the progression of carcinoma of the breast is discussed.

Effects of single-dose and fractionated cranial irradiation on rat brain accumulation of methotrexate

The effects of single-dose and fractionated whole-brain irradiation on brain methotrexate (MTX) has been studied in a rat model. The amount of MTX present in the brain 24 hr after a single i.p. dose (100 mg/kg) was the same wether animals were sham irradiated or given a single dose of 2000 rads 6 or 48 hr prior to the drug (6.9, 8.3, and 6.8 pmol MTX/g, wet weight, respectively). Animals sham irradiated or given 2000 rads in 10 fractions over 11 days and treated with an average dose of 1.2 mg MTX/kg i.p. twice a week for 24 weeks did not differ significantly in their brain MTX concentration (7.9 and 8.3 pmol MTX/g, wet weight, respectively). Chronically MTX-treated animals became folate deficient whether they were irradiated or not (450 and 670 pmol folate/g, wet weight, brain in MTX-treated and control animals). Thus, MTX accumulates in the brain with acute or chronic administration, and this accumulation is not altered by this amount of brain irradiation.

Molecular orbital studies of epoxide stability of carcinogenic polycyclic aromatic hydrocarbon diol epoxides

Semiempirical molecular orbital calculations (by modified neglect of diatomic overlap method) were performed on diol epoxide metabolites of five polycyclic aromatic hydrocarbons (PAHs)--benzene, naphthalene, phenanthrene, chrysene, and benzo[a]pyrene (BP)--to gain insight into the various carcinogenic potencies of these compounds. Opening of the epoxide rings of the diol epoxides was calculated to be exothermic for all of the PAHs investigated. The bay-region diol epoxides of BP were calculated to open spontaneously to the triol carbonium ion upon protonation. For the bay-region trans- and cis-diequatorial diol epoxides of 5-methylchrysene the methyl group destabilized the epoxide. These results suggest that the conformation of the saturated, angular benzo-ring is important in determining bay-region epoxide stability. Conformational flexibility of the aromatic ring system is offered as one reason for partial stabilizing of bay-region epoxides. These results also suggest that the existence and potentiation of PAH carcinogenicity is correlated with the lack of stability of the bay-region epoxide ring. Considerations of thermochemical stability have value in predictions of carcinogenic potency.

Making physiotherapy more accessible: open access for general practitioners to a physiotherapy department

Open access to a physiotherapy outpatient department of a district general hospital was offered to general practitioners to whom domiciliary physiotherapy was already available. The effects of the new service have been monitored. Delays are reduced and consultants economise on time spent in merely confirming need for physiotherapy. Policies determining treatment, placing emphasis on prevention and self-help rather than prolonged treatment, are adhered to equally well by physiotherapists whether patients are referred directly or indirectly. It had proved unnecessary to restrict access to physiotherapy by insisting that general practitioners refer all patients first to consultant clinics. General practitioners have been sufficiently selective in referral and physiotherapists sufficiently economical in selecting treatment and determining its duration for the service to remain within the limits of available resources.

Metabolism of dichlorobiphenyls by highly purified isozymes of rat liver cytochrome P-450

Hepatic mixed-function oxidase metabolism of the ubiquitous pollutant polychlorinated biphenyls (PCBs) is implicated in their toxification and detoxification. We used dichlorobiphenyls (DCBs) as models to investigate the effect of the chloro substituent sites on this metabolism experimentally and by molecular orbital calculations. Reconstituted, purified cytochrome P-450 PB-B and BNF-B, the major terminal oxidase isozymes of this system, from phenobarbital (PB)- and beta-naphthoflavone (BNF)-induced rats were used to investigate this metabolism. Both isozymes are also induced by PCBs. High-performance liquid chromatography (HPLC) was used to detect, quantify, and isolate metabolites. Metabolite structures were identified by mass spectrometry, dechlorination to identifiable hydroxybiphenyls, and HPLC retention times. All DCBs yielded 3- and 4- but no 2-monohydroxylated metabolites (3,3'-DCB also yielded a dihydroxy metabolite). Di-o-chloro-substituted DCBs were metabolized primarily by cytochrome P-450 PB-B, mono-o-chloro substituted DCBs by both isozymes approximately equivalently, and DCBs without o-chloro substituents by BNF-B primarily. Thus PB-B preferentially metabolizes noncoplanar DCBs and BNF-B coplanar DCBs. The cytochrome isozymes exhibited differing regioselectivities for DCB metabolism - PB-B hydroxylated unchlorinated phenyl rings and BNF-B chlorinated rings. Incorporation of epoxide hydrolase yielded DCB dihydrodiols, and hydroxy metabolite patterns were consistent with those calculated from ring-opened arene oxide intermediates. Thus the rates and regioselectivities of metabolism and thus possibly the toxicity and carcinogenicity of DCBs are dependent on the cytochrome P-450 isozymes induced.

Psychrophile C-phycocyanin

C-Phycocyanin was purified from an alga isolated in the Antarctic in 1968 and grown since that time in our laboratory at 4 C. Certain of its spectroscopic and immunochemical properties were studied, along with detailed examinations of its chemical composition and quaternary structure. The hexamer-trimer equilibrium in the protein solution was studied as a function of pH, ionic strength, temperature, and susceptibility to certain small molecules. A major emphasis of the work was placed on a comparison of its protein-protein interactions with those of C-phycocyanins from both mesophilic and thermophilic algae.

Detection of benzoylecgonine in human urine

A thin-layer chromatography (TLC) method is described that can be used to detect benzoylecgonine (BE), a metabolite of cocaine, in human urine. It is a two-part procedure that can be integrated into a rapid screening program for drug abuse. The first part of the method utilizes two TLC solvent systems to identify a variety of drugs, including BE. The second part is specific for the cocaine metabolite and can be used as a confirmation method. The procedure is sensitive to 3-4 microgram/ml of BE in urine.

Radioimmunuassay compared to thin-layer and gas--liquid chromatography for detecting methadone in human urine

Radioimmunoassay was compared to thin-layer and gas--liquid chromatographic methods for detection of methadone in the urine of patients undergoing methadone maintenance therapy as treatment of heroin abuse. With urine samples known to contain methadone, 84% were positive by thin-layer chromatography as compared to 99% positives by the other two methods. This difference is attributed to the difference in sensitivity of the three methods. All three methods gave consistently positive results with urine samples from patients receiving 25 mg of methadone per day or more. With smaller daily doses the percentage of positive results obtained with thin-layer chromatography decreased. Analysis of urine samples not containing methadone showed no incidence of cross reaction of other drugs with the methadone radioimmunoassay. The methadone radioimmunoassay appears to be both sensitive and reliable; however, certain other factors limit its use as a primary screening method.

Radioimmunuassay compared to thin-layer and gas--liquid chromatography for detecting methadone in human urine

Radioimmunoassay was compared to thin-layer and gas--liquid chromatographic methods for detection of methadone in the urine of patients undergoing methadone maintenance therapy as treatment of heroin abuse. With urine samples known to contain methadone, 84% were positive by thin-layer chromatography as compared to 99% positives by the other two methods. This difference is attributed to the difference in sensitivity of the three methods. All three methods gave consistently positive results with urine samples from patients receiving 25 mg of methadone per day or more. With smaller daily doses the percentage of positive results obtained with thin-layer chromatography decreased. Analysis of urine samples not containing methadone showed no incidence of cross reaction of other drugs with the methadone radioimmunoassay. The methadone radioimmunoassay appears to be both sensitive and reliable; however, certain other factors limit its use as a primary screening method.