Biomedical subjects

R F Smith

Publications and source records attributed to R F Smith.

At least 55 records · Page 3Linked to original sources

PubMed1998

BEAUTY-X: enhanced BLAST searches for DNA queries.

UNLABELLED: BEAUTY (BLAST Enhanced Alignment Utility) is an enhanced version of the BLAST database search tool that facilitates identification of the functions of matched sequences. Three recent improvements to the BEAUTY program described here make the enhanced output (1) available for DNA queries, (2) available for searches of any protein database, and (3) more up-to-date, with periodic updates of the domain information. AVAILABILITY: BEAUTY searches of the NCBI and EMBL non-redundant protein sequence databases are available from the BCM Search Launcher Web pages (http://gc.bcm.tmc. edu:8088/search-launcher/launcher.html). BEAUTY Post-Processing of submitted search results is available using the BCM Search Launcher Batch Client (version 2.6) (ftp://gc.bcm.tmc. edu/pub/software/search-launcher/). SUPPLEMENTARY INFORMATION: Example figures are available at http://dot.bcm.tmc. edu:9331/papers/beautypp.html CONTACT: (kworley,culpep)@bcm.tmc.edu

Amino Acid Sequence↗

PubMed1998

Effect of prolonged exposure to oestradiol on subsequent LH secretion in ewes.

Abnormal follicles can produce oestradiol continuously for up to 20 days and this inhibits the hypothalamic-pituitary axis. The present experimental series was designed to determine the minimum exposure to high or low follicular phase concentrations of oestradiol that were required to exert inhibitory effects on LH surge secretion induced by additional oestradiol administered at the end of continuous exposure to oestradiol. Experiments were also included to establish whether the inhibitory effects of prolonged oestradiol were mediated at the pituitary, and whether the failure of response to the oestradiol challenge could be corrected by exposure to normal luteal phase patterns of progesterone. Treatment of ewes between 2 and 12 days with 1, 2 or 4 oestradiol implants (3 cm) totally blocked the subsequent normal LH surge in response to an oestradiol challenge in 45 of 52 ewes pretreated with oestradiol. In the seven ewes that did have an increase in LH, the response occurred at the expected time but was greatly reduced (14 versus 40 ng ml-1), and occurred only in ewes pretreated with oestradiol implants for 2 or 4 days. We were unable to establish a robust linear time-dose relationship, i.e., when ewes were treated with lower doses of oestradiol (one or two implants) for a reduced time (2, 4 or 8 days), there was random distribution of the 7 of 32 animals that had a reduced LH surge after oestradiol challenge (with four implants or 50 micrograms injection). The present study is the first to show that exposure for only 2-4 days to continuous oestradiol at late follicular phase concentrations can disrupt LH surge release. However, in oestradiol-treated ewes, LH secretion was provoked by high or low doses (0.5 mg or 0.5 microgram) of GnRH, although it was reduced by 50%, and a GnRH self-priming effect was still evident. All of these results suggest that inhibitory effects occur at the pituitary and hypothalamus. It remains to be confirmed whether the major effect is at the pituitary by reducing GnRH receptor or LH synthesis, or at the hypothalamus via inhibition of GnRH secretion.

Analysis of Variance↗

PubMed1998

Assessment of simple colorimetric procedures to determine smoking status of diabetic subjects.

The performance of a simple colorimetric assay for urinary nicotine metabolites to assess smoking status in diabetic subjects (n = 251) was investigated. Several variations of the colorimetric assay and a qualitative extraction procedure were evaluated in comparison with a cotinine immunoassay as the "gold standard." Among these, the best overall performance was achieved with the qualitative test (sensitivity 95%; specificity 100%). The quantitative measurement of total nicotine metabolites performed less well (sensitivity 92%; specificity 97%) but could be improved by incorporating a blank extraction (sensitivity 98%; specificity 98%). Allowance for diuresis appeared to offer no advantage over the other methods. These results support previous findings regarding the use of these colorimetric procedures in nondiabetic subjects and, contrary to other recent observations, their performance was not impaired in diabetic patients.

Colorimetry↗

PubMed1997

Effect of adrenocorticotrophic hormone on gonadotrophin releasing hormone-induced luteinizing hormone secretion in vitro.

An in vitro perifusion study investigated the effect of different forms of adrenocorticotrophic hormone (ACTH) on gonadotrophin releasing hormone (GnRH)-induced luteinizing hormone (LH) secretion, particularly GnRH self-priming, and oestradiol sensitisation of the ovine pituitary. Fragments of pituitaries were obtained from mixed-breed adult nonpregnant female sheep (without corpora lutea, unless otherwise stated). The amount of LH released by different doses of GnRH (2.5 x 10(-10) M (n = 9 chambers), 1 x 10(-10) M (n = 9), or 5 x 10(-11) M (n = 6)) was evaluated by giving two GnRH pulses (5 min each) 2 h apart. In a duplicate set of chambers, ACTH1-24 (5 x 10(-7) M) was included in the perifusate 0.5 h before the first GnRH challenge. Potassium chloride (KCl; 100 mM) was administered 2 h after the second GnRH challenge to assess the viability of the tissue and the size of the releasable LH pool. Results were expressed as percentage of LH secretion. The influence of ACTH1-24 on oestradiol sensitisation was also examined using pituitaries obtained during the luteal phase. Pituitary tissues were perifused throughout with 1 x 10(-9) M or 6 x 10(-11) M oestradiol in the medium. The LH response to the second GnRH challenge (GnRH 2) was significantly greater (p < 0.01) than after the first (GnRH 1) at the highest dose of GnRH (2.5 x 10(-10) M; 2547 +/- 804 vs. 4547 +/- 1013%), but at the lower doses (1 x 10(-10) M or 5 x 10(-11) M), the self-priming effect of GnRH was not evident (3016 +/- 550 vs. 2932 +/- 490% and 841 +/- 205 vs. 711 +/- 87%). Treatment with ACTH1-24 (5 x 10(-7) M) did not affect tonic LH secretion nor the LH response to the first or second GnRH challenge at any of the GnRH doses tested. The LH released in response to KCl was also similar from control and ACTH1-24-treated tissue at all GnRH doses. Both lower doses of GnRH (1 x 10(-10) M or 5 x 10(-11) M) produced the self-priming effect when the pituitary tissue was sensitised with the higher dose of oestradiol (1 x 10(-9) M; 1711 +/- 239 vs. 5085 +/- 1307%, and 1502 +/- 376 vs. 2619 +/- 629%). In the presence of lower concentrations of oestradiol (6 x 10(-11) M), self-priming was observed only after the higher dose of GnRH (1 x 10(-10) M; 1293 +/- 214 vs. 2865 +/- 436%), not the lower dose (5 x 10(-11) M; 985 +/- 203 vs. 1271 +/- 436%). In spite of these differences, ACTH1-24 treatment did not affect LH secretion (neither basal nor potassium-induced). The effect of ACTH1-39 (1 x 10(-8) M or 5 x 10(-7) M; n = 6 chambers per combination) on GnRH-induced LH secretion was examined using the higher (2.5 x 10(-10) M) or lower dose of GnRH (1 x 10(-10) M), with or without oestradiol sensitisation (1 x 10(-9) M). At the lower dose (1 x 10(-8) M), ACTH1-39 influenced neither tonic nor GnRH-induced LH secretion. The LH released by KCl was also similar to the control and ACTH-treated tissue. In contrast, the higher dose of ACTH1-39 (5 x 10(-7) M) increased tonic LH secretion immediately after inclusion in the medium (104 +/- 3 vs. 161 +/- 20%), but suppressed the GnRH self-priming effect after 2.5 x 10(-10) M, i.e., the LH responses to GnRH 1 and 2 were similar (1786 +/- 294 vs. 1553 +/- 373%). However, the LH response to KCl was not significantly different (p > 0.05) between the control and ACTH-treated tissues (2333 +/- 286 vs. 2638 +/- 431%). When the effect of this higher dose of ACTH1-39 on oestradiol-priming was investigated, ACTH increased tonic LH secretion but suppressed the self-priming effect of GnRH (1 x 10(-10) M GnRH; 945 +/- 274 vs. 922 +/- 323%; p > 0.05), and decreased (p < 0.05) the LH released in response to KCl compared to the controls (1803 +/- 409 vs. 4302 +/- 1017%). In summary, in vitro, ACTH1-24 did not affect either tonic LH secretion, the GnRH self-priming effect, or oestradiol sensitisation. The entire ACTH1-39 increased tonic LH secretion, but reduced GnRH self-priming and oestradiol sensitisation. (ABSTRACT TRUNCATED)

Adrenocorticotropic Hormone↗

PubMed1997

Routine preoperative "one-shot" intravenous pyelography is not indicated in all patients with penetrating abdominal trauma.

BACKGROUND: To determine which patients need a "one-shot" intravenous pyelogram (IVP) before laparotomy for penetrating abdominal trauma. STUDY DESIGN: Over a 15-month period, 240 laparotomies were performed for penetrating trauma at our urban level I trauma center. Prospectively collected data included clinical suspicion of genitourinary injury, results of preoperative IVP, intraoperative findings, and operative decisions influenced by the IVP. RESULTS: Preoperative IVP was performed in 175 patients (73%). Of these, 71 (41%) had suspicion of a renal injury based on the presence of a flank wound or gross hematuria. The IVP was believed to influence operative decisions in six patients, all in this group. Each of these six patients had either a shattered kidney or a renovascular injury and had a nephrectomy performed with the knowledge that a normal functioning kidney was present on the contralateral side. No patient without a flank wound or gross hematuria had an IVP that was judged to be helpful intraoperatively. Preoperative IVP was helpful only in patients with flank wounds or gross hematuria. Nephrectomy was performed in two additional patients who did not undergo IVP, both of whom presented in shock. CONCLUSIONS: Routine preoperative IVP is not necessary in all patients undergoing laparotomy for penetrating trauma. The number of IVPs can be safely reduced by 60% if the indications are narrowed to include only those stable patients with a flank wound or gross hematuria.

Abdominal Injuries↗

PubMed1997

Amino acid substitutions preserve protein folding by conserving steric and hydrophobicity properties.

We present a comprehensive analysis of amino acid substitution patterns (sets of residues in a position of a multiple alignment) and conservation of physicochemical properties in alignments of protein sequences. Of the one million possible substitution patterns, only a few hundred account for the majority of aligned positions. Very similar distributions of substitution patterns are observed in all but one of the diverse databases of multiple alignments. In these substitution patterns we analyzed the conservation of 511 physicochemical and steric amino acid properties. Highest conservation was observed in those steric and transfer free energy-related properties that are crucial for folding. The best conserved steric properties include the minimal width of the side chains and their interactions with other residues. Among the hydrophobicity-related properties, charge and those properties that provide information on propensities to form secondary structures or side chain conformation, appear to be better conserved than pure hydrophobicity measures. Physicochemical sequence analysis based on the most conserved properties is expected to aid searching a protein sequence query against a database of multiple alignments, prediction of secondary and tertiary structures and protein engineering.

Amino Acids↗

PubMed1997

Effects of cone-induction treatments on black spruce (Picea mariana) current-year needle development and gas exchange properties.

Both drought and root pruning (RP) increased the number of cones induced when black spruce (Picea mariana (Mill.) B.S.P.) grafts were injected with gibberellins A(4/7) (GA), but their effects on predawn shoot water potential and current-year needle development differed. Drought decreased predawn shoot water potential (Psi(pd)), but only during the period when irrigation was withheld, and it had no effect on the growth or gas exchange properties of current-year needles. Conversely, root pruning had little effect on Psi(pd), but it resulted in trees with smaller current-year needles that had lower nitrogen and chlorophyll concentrations and reduced rates of gas exchange up to the later stages of shoot elongation compared with needles of control trees. These findings are discussed in relation to potential effects on the development of induced cones in the following growth cycle.

Journal Article↗

PubMed1997

A method of determining peritoneal penetration in gunshot wounds to the abdomen.

BACKGROUND: It has previously been shown that 98% of gunshot wounds that penetrate the peritoneal cavity cause injuries that require surgical repair. Many gunshot wounds in the vicinity of the abdomen (GSWA) may actually be tangential and not penetrate the peritoneal cavity at all. Patients with such wounds may not require laparotomy. It is important to determine which patients with a potential tangential GSWA actually have penetration of the peritoneal cavity to minimize negative laparotomies. This study was undertaken to determine the sensitivity, specificity, and accuracy of diagnostic peritoneal lavage (DPL) in the determination of peritoneal penetration for patients who sustain GSWA. METHODS: DPL was performed for all patients who had sustained a GSWA in whom peritoneal penetration was unclear, i.e., patients whose GSWA appeared to be tangential, thoracoabdominal, or transpelvic and for whom a clear indication for laparotomy (shock, peritonitis, etc.) did not exist. Our threshold for a positive DPL was 10,000 red blood cells (RBC)/mm3. A prospective data base was kept with information on the location of the wound, DPL result, findings at laparotomy, and outcome. RESULTS: During a 4-year period, 429 consecutive DPLs were performed for GSWA at our urban Level I trauma center. One hundred fifty DPLs were positive, with more than 10,000 RBC/mm3. Six of these patients were found to have no peritoneal penetration at laparotomy (false-positive). The remaining 144 patients with positive DPLs were found to have operative injuries (true-positive). Of the 279 patients with DPL counts less than 10,000 RBC/mm3, 2 developed indications for laparotomy and were found to have intraperitoneal injuries (false-negative). The remaining 277 patients had no peritoneal injuries (true-negative). This was demonstrated either by laparotomy done for another indication (n = 7) or by uneventful inpatient observation for 24 hours (n = 270). The sensitivity, specificity, and accuracy of DPL in determining peritoneal penetration in GSWA is therefore 99, 98, and 98%, respectively. CONCLUSION: For patients who sustain GSWA for whom peritoneal penetration is unclear, DPL is a sensitive, specific, and accurate test to determine the need for laparotomy. It remains our test of choice when confronted with these patients.

Abdominal Injuries↗

PubMed1996

FASTA-SWAP and FASTA-PAT: pattern database searches using combinations of aligned amino acids, and a novel scoring theory.

We introduce two new pattern database search tools that utilize statistical significance and information theory to improve protein function identification. Both the general pattern scoring theory with the specific matrices introduced here and the low redundancy of pattern databases increase search sensitivity and selectivity. Pattern scoring preferentially rewards matches at conserved positions in a pattern with higher scores than matches at variable positions, and assigns more negative scores to mismatches at conserved positions than to mismatches at variable positions. The theory of pattern scoring can be used to create log-odds pattern scores for patterns derived from any set of multiple alignments. This theoretical framework can be used to adapt existing sequence database search tools to pattern analysis. Our FASTA-SWAP and FASTA-PAT tools are extensions of the FASTA program that search a sequence query against a pattern database. In the first step, FASTA-SWAP searches the diagonals of the query sequence and the library pattern for high-scoring segments, while FASTA-PAT performs an extended version of hashing. In the second step, both methods refine the alignments and the scores using dynamic programming. The tools utilize an extremely compact binary representation of all possible combinations of amino acid residues in aligned positions. Our FASTA-SWAP and FASTA-PAT tools are well suited for functional identification of distant relatives that may be missed by sequence database search methods. FASTA-SWAP and FASTA-PAT searches can be performed using our World-Wide Web Server (http://dot.imgen.bcm.tmc.edu:9331/seq-search/Op tions/fastapat.html).

Algorithms↗

PubMed1996

Safety of 65 degrees C intravenous fluid for the treatment of hypothermia.

BACKGROUND: To demonstrate the safety and efficacy of 65 degrees C (149 degrees F) centrally administered intravenous fluid (CIVF) compared to conventional 40 degrees C (104 degrees F) CIVF in the treatment of hypothermia. METHOD: Ten beagles (9-13 kg) were prospectively randomized to receive 65 degrees C or 40 degrees C CIVF. They were anesthetized and data were collected at baseline, during hypothermia, and after 1 and 2 hours of rewarming. The plasma free/total hemoglobin (PFHb/THb) was measured to detect hemolysis. Each subject was cooled to 30 degrees C (86 degrees F) and then received either 65 degrees C or 40 degrees C CIVF through a specialized catheter in the superior vena cava for 2 hours in addition to conventional rewarming techniques. All subjects survived 7 days, after which they were sacrificed and a complete autopsy was performed. RESULTS: The rewarming rate was 3.7 degrees C/hr in the 65 degrees C CIVF group and 1.75 degrees C/hr in the 40 degrees C CIVF group. Core temperatures were significantly different after 1 hour (33.4 degrees +/- 0.77 degrees versus 31.7 degrees +/- 0.57 degrees, P < 0.01) and 2 hours (37 degrees +/- 1.03 degrees versus 33.4 degrees +/- 0.89 degrees, P < 0.001). PFHb/THb was not different. Two intimal injuries occurred in each group but these were remote from the infusion site. Blinded examination by two pathologists could not differentiate the etiology of these injuries from mechanical trauma. CONCLUSION: CIVF at 65 degrees C is a safe and effective means of treating hypothermia.

Animals↗

PubMed1996

Geometric characterization of stenosed human carotid arteries.

RATIONALE AND OBJECTIVES: The geometry of stenosed carotid bifurcations was analyzed to determine average representations for several stenosis grades. METHODS: Film angiograms of 62 patients with internal carotid artery stenoses were digitized. Residual lumen boundaries were manually outlined. The outlines were processed with a computer to extract geometric measurements. The measurements were grouped according to stenosis grade and used to create average representations. RESULTS: Accuracy and precision of the outlining technique were +/- 0.020 common carotid diameters (CCD) and +/- 0.025 CCD, respectively. Maximum narrowing of the internal carotid artery occurred at 0.3 CCD +/- 1.5 (mean +/- standard deviation) distal to the flow divider. The region of significant narrowing extended axially 1.2 CCD +/- 1.0. Poststenotic dilatations were observed, with enlargement of 1.3 +/- 0.7 times the normal diameter of the distal internal carotid artery. A tendency toward smaller bifurcation angles with increasing stenosis severity was observed. CONCLUSION: Three-dimensional geometric models could be created for carotid bifurcations that were disease free (normal) and of arbitrary stenosis grade.

Aged↗

PubMed1996

Establishing the cut-off concentration for the detection of etorphine in horse urine.

An 125I radioimmunoassay to determine the pattern of urinary excretion of etorphine (a semisynthetic opiate agonist) after its administration to horses is described. Three thoroughbred horses were each given 5, 15, 30 and 100 micrograms of etorphine intramuscularly. Urine was collected for up to 72 after administration. The maximum etorphine concentration after administration of a dose of 5 micrograms was 711 pg ml-1 (concentrations were greater than 100 pg ml-1 after 23 h in all three horses); a 15 micrograms gave 2661 pg ml-1 (levels remained above 100 pg ml-1 for more than 44 h in each horse); a 30 micrograms dose gave a maximum of 3344 pg ml-1 (levels were above 100 pg ml-1 for 24, 72 and 72 h); and 100 micrograms gave in excess of 10,000 pg ml-1 (levels were greater than 300 pg ml-1 for up to 70 h). Forty-eight urine samples from horses not given etorphine all had levels of etorphine less than 100 pg ml-1. There was no increase in apparent etorphine concentrations after hydrolysis of samples with beta-glucuronidase and aryl sulfatase. The half-lives of etorphine equivalents (calculated with a mono-exponential equation after the 100 micrograms dose) in the urine of the three horses were 569, 803 and 821 min, respectively. We conclude that radioimmunoassay can provide a useful first line screening procedure for the assessment of etorphine use in racing horses.

Animals↗

PubMed1996

BCM Search Launcher--an integrated interface to molecular biology data base search and analysis services available on the World Wide Web.

The BCM Search Launcher is an integrated set of World Wide Web (WWW) pages that organize molecular biology-related search and analysis services available on the WWW by function, and provide a single point of entry for related searches. The Protein Sequence Search Page, for example, provides a single sequence entry form for submitting sequences to WWW servers that offer remote access to a variety of different protein sequence search tools, including BLAST, FASTA, Smith-Waterman, BEAUTY, PROSITE, and BLOCKS searches. Other Launch pages provide access to (1) nucleic acid sequence searches, (2) multiple and pair-wise sequence alignments, (3) gene feature searches, (4) protein secondary structure prediction, and (5) miscellaneous sequence utilities (e.g., six-frame translation). The BCM Search Launcher also provides a mechanism to extend the utility of other WWW services by adding supplementary hypertext links to results returned by remote servers. For example, links to the NCBI's Entrez data base and to the Sequence Retrieval System (SRS) are added to search results returned by the NCBI's WWW BLAST server. These links provide easy access to auxiliary information, such as Medline abstracts, that can be extremely helpful when analyzing BLAST data base hits. For new or infrequent users of sequence data base search tools, we have preset the default search parameters to provide the most informative first-pass sequence analysis possible. We have also developed a batch client interface for Unix and Macintosh computers that allows multiple input sequences to be searched automatically as a background task, with the results returned as individual HTML documents directly to the user's system. The BCM Search Launcher and batch client are available on the WWW at URL http:@gc.bcm.tmc.edu:8088/search-launcher.html.

Animals↗

PubMed1996

A comparative transcription map of the murine bare patches (Bpa) and striated (Str) critical regions and human Xq28.

The X-linked developmental mouse mutations bare patches (Bpa) and striated (Str) may be homologous to human X-linked dominant chondrodysplasia punctata (CDPX2) and incontinentia pigmenti (IP2), respectively, based on their genetic mapping and clinical phenotypes. Bpa and Str have been localized to an overlapping critical region of 600 kb that demonstrates conserved gene order with loci in human Xq28 between DXS1104 and DXS52. As part of efforts to isolate the genes involved in these disorders, we have begun to develop a comparative transcription map spanning this region in both species. Using techniques of cross-species conservation and hybridization, exon trapping, and cDNA selection we have identified four known genes or members of gene families--caltractin, a member of the gamma-aminobutyric acid (GABAA) receptor gene family, a member of the melanoma antigen gene (MAGE) family, and several members of the murine-specific, X-linked lymphocyte regulated gene (Xlr3) family. Trapped exons and, in some cases, longer cDNAs have been isolated for potentially 7-9 additional genes. One cDNA demonstrates highly significant homology with members of the Krüppel family of zinc finger transcription factors. A second novel cDNA demonstrates homology at the 3' end of the predicted amino acid sequence to a LIM domain consensus. Gene order appears conserved among those cDNAs determined to be present in both human and mouse. Three of the murine transcripts appear to be present in multiple copies within the Bpa/Str critical region and could be associated with a predisposition to genomic rearrangements. Reverse transcriptase PCR (RT-PCR) and Northern analysis demonstrate that several of the transcripts are expressed in mid-gestation murine embryos and neonatal skin, making them candidates for the Bpa and Str mutations and their respective homologous human disorders.

Amino Acid Sequence↗

PubMed1996

Perspectives: sequence data base searching in the era of large-scale genomic sequencing.

Large-scale sequencing of human and model organism genomes will have a profound impact on our ability to use sequence data base searching to predict the biochemical functions of sequences of interest. Despite the great value of more sequences in the data bases, a huge increase in data base size will also have adverse effects on data base searches. Upcoming problems will include (1) greatly increased search times, (2) an increase in background noise of high-scoring but biologically irrelevant matches, (3) inaccurate coding region prediction, leading to problems in protein data base searching, and (4) limited first-pass sequence annotation, making it difficult to determine the biological relevance of data base hits. Improved data base annotation tools and construction of smaller data bases of representative and highly-annotated sequences for first-pass analyses will be essential to deal with the impending flood of new genomic sequence.

Animals↗

PubMed1995

Identification of a eukaryotic-like protein kinase gene in Archaebacteria.

Primary sequence patterns based on known conserved sites in eukaryotic protein kinases were used to search for eukaryotic-like protein kinase sequences in a six-frame translation of the bacterial subsection of GenBank. This search identified a previously unrecognized eukaryotic-like protein kinase gene in three related methanogenic archaebacteria, Methanococcus vannielii, M. voltae, and M. thermolithotrophicus. The proposed coding sequences are located in orthologous open reading frames (ORFs): ORF547, ORF294, and ORF114, respectively. The C-terminus of the ORFs contains 9 of the 11 subdomains characteristically conserved within the eukaryotic protein kinase catalytic domain. The N-terminus of the ORFs is similar to a putative glycoprotease in Pasteurella haemolytica and its homologue in Escherichia coli, the orfX gene. This is the first report of a eukaryotic-like protein kinase sequence observed in Archaebacteria.

Amino Acid Sequence↗

PubMed1995

Prenatal cocaine produces dose-dependent suppression of prolactin and growth hormone in neonatal rats.

Pregnant Long-Evans hooded rats were dosed with 5, 10, 20, or 40 mg/kg/d cocaine from GD7 through GD20; pairfed/vehicle-injected, and uninjected controls were included. At birth, representative pups from each litter were killed by decapitation and serum assayed for prolactin and growth hormone via radioimmunoassay. Prolactin levels were significantly reduced on P1 in offspring which had been dosed prenatally with 20 or 40 mg/kg/d, while growth hormone levels were significantly lower than control levels in the 5 and 10 mg/kg/d animals. Pairfed/vehicle controls did not differ from uninjected controls on levels of either hormone. These endocrine changes associated with cocaine dosing may affect subsequent development of the organism.

Animals↗

PubMed1995

Transport-induced stress responses in fed and fasted donkeys.

Plasma endocrine and metabolic responses to transport for 30 minutes and four hours were investigated in six fed donkeys. In the unstressed animals there was a pulsatile secretion of cortisol at two-hour intervals, from minima of 51.4 +/- 17.6 nmol litre-1 to maxima of 160.0 +/- 11.0 nmol litre-1, but during transport this pulsatility was lost and the animals' stress response was characterised by steady high concentrations of 110 to 220 nmol litre-1. The cortisol concentration decreased after the journey and remained at a minimum until the restoration of pulsatile secretion 8.5 to 10.5 hours later. The transport-induced adrenocortical response did not produce any significant changes in the plasma concentrations of triglycerides, cholesterol, glucose, total protein, albumin, globulin or urea. The donkeys' responses to transport for four hours were also investigated after they had been deprived of food for one or three days. Food deprivation alone increased plasma cortisol and triglyceride concentrations, and decreased glucose and insulin concentrations, and transport consistently, and feeding after the journey sometimes, accentuated their adrenocortical function; the changes in cortisol concentrations as a result of the journey tended to be lower than in the fed animals. Transport had no effect upon the triglyceride response to either period of fasting. Hyperglycaemia was induced by transport in four of the six donkeys fasted for one day and in all of them after three days of fasting.

Analysis of Variance↗