Disposition of ampicillin trihydrate in plasma, uterine tissue, lochial fluid, and milk of postpartum dairy cattle.

The objective of this study was to determine the disposition of ampicillin in plasma, uterine tissue, lochial fluid, and milk of postpartum dairy cattle. Ampicillin trihydrate was administered by intramuscular (i.m.) injection at a dose of 11 mg/kg of body weight every 24 h (n = 6, total of 3 doses) or every 12 h (n = 6, total of 5 doses) for 3 days. Concentrations of ampicillin were measured in plasma, uterine tissue, lochial fluid, and milk using HPLC with ultraviolet absorption. Quantifiable ampicillin concentrations were found in plasma, milk, and lochial fluid of all cattle within 30 min, 4 h, and 4 h of administration of ampicillin trihydrate, respectively. There was no significant effect of dosing interval (every 12 vs. every 24 h) and no significant interactions between dosing interval and sampling site on the pharmacokinetic variable measured or calculated. Median peak ampicillin concentration at steady-state was significantly higher in lochial fluid (5.27 µg/mL after q 24 h dosing) than other body fluids or tissues and significantly higher in plasma (3.11 µg/mL) compared to milk (0.49 µg/mL) or endometrial tissue (1.55 µg/mL). Ampicillin trihydrate administered once daily by the i.m. route at the label dose of 11 mg/kg of body weight achieves therapeutic concentrations in the milk, lochial fluid, and endometrial tissue of healthy postpartum dairy cattle.

Antiparasitic efficacy of a novel plant-based functional food using an Ascaris suum model in pigs.

Ascaris lumbricoides is the most prevalent soil-transmitted helminth (STH) infection of human beings worldwide. Chemotherapy with synthetic anthelmintics such as albendazole, mebendazole, and pyrantel pamoate is the current method of treatment; however, the emergence of anthelmintic resistance could substantially decrease the efficacy of such treatments and the sustainability of STH control programs. Additionally, benzimidazoles are not recommended for pregnant women or children under age one. A blinded, controlled study was conducted to evaluate the efficacy of two microencapsulated, plant-based essential oil blends, TTN1013 (α-pinene, linalyl acetate, p-cymene, and thymol octanoate) and TTN1014 (α-pinene, linalyl acetate, p-cymene, and thymol acetate) as functional foods against Ascaris suum infection in pigs, an important pathogen that closely resembles human infections with A. lumbricoides. Four groups of 16 female, 21-24 day old, Yorkshire-cross pigs were treated daily with 0.5 or 1.0mg/kg TTN1013, 1.0mg/kg TTN1014, or 1.0mg/kg equivalent of empty capsules, delivered inside a cream-filled sandwich cookie for 14 weeks. Three days after the initiation of daily treatments, pigs were inoculated daily with A. suum eggs for four weeks. Pigs were weighed weekly and fecal egg counts (FEC) were conducted weekly starting five weeks after initial inoculation with A. suum eggs. Fourteen weeks after first infection with eggs, pigs were necropsied and worms were recovered, counted and separated according to sex. TTN1013 administered daily at a dose of 1.0mg/kg yielded a statistically significant reduction in total worm counts (76.8%), female worm counts (75.5%), FEC (68.6%), and worm volume (62.9%) when compared to control group. Reduction of total and female worm numbers and FEC were not significant for TTN1014 or at the 0.5mg/kg dose of TTN1013. All treatments were well-tolerated by all pigs and did not cause any adverse reactions. All pigs remained clinically normal and showed no signs of reduced intestinal health for the duration of treatment. Based on these results, TTN1013 shows promise as a daily supplement to reduce infection burdens of soil transmitted helminths in both pigs and human beings.

Adverse outcomes in orthognathic surgery and management of residual problems.

Adverse outcomes in orthognathic surgery include both functional and aesthetic components that frequently coexist. Reasons for this occurrence are multifactorial and can be classified in broad categories of diagnosis, treatment planning, technical execution, and unpreventable outcomes. Management of the residual deformities is both functional and aesthetic as based on correctly delineating the problem and its cause.

Defense response in slash pine: chitosan treatment alters the abundance of specific mRNAs.

We used differential display to identify chitosan responsive cDNAs in slash pine cell cultures. Two clones that showed increased mRNA abundance had sequence similarity to genes with roles in major plant defense responses, clone 18 to cinnamic acid 4-hydroxylase, and clone 30 to chitinase.

mRNA encoding human thyroglobulin's C-terminus is heterogeneous.

Thyroglobulin (Tg) provides the peptide backbone for synthesis for thyroid hormones. Because previous studies by various techniques have raised the possibility of heterogeneity in Tg's message and translated protein, we have applied a highly sensitive ribonuclease protection assay (RPA) to examine the mRNA species translating part of Tg's C-terminal region, an area containing three of Tg's hormonogenic sites. Tissue samples were obtained from 18 normal and diseased human thyroids at surgery. Three probes spanning part or all of the nucleotide segment containing bases 7808-8086 in the cDNA sequence, detected full-length mRNAs as the dominant transcripts but also showed the consistent presence of at least seven discrete smaller mRNA species in the thyroid samples. The amounts of these smaller mRNAs varied among tissue samples without a discernible relationship to the underlying clinical thyroid condition. We conclude that the mRNA for this region of Tg is quite heterogeneous and offers potential opportunities for translation of different peptide sequences that might affect hormonogenesis in the C-terminal region of the protein.

Thyroids from siblings with Pendred's syndrome contain thyroglobulin messenger ribonucleic acid variants.

We studied thyroid tissue from two siblings with Pendred's syndrome (familial goiter and congenital deafness), both with the Mondini-type inner ear malformation, goiter, and hypothyroidism. Iodine trapping and peroxidase levels were grossly normal. Thyroglobulin (Tg), the only iodoprotein found, had a normal monomer size (330 kilodaltons), but low content of hormone and iodine. Tg's expected N-terminal peptides of 26 and 18 kilodaltons, usually formed in association with iodination and thyroid hormone synthesis, were absent, but appeared after iodination in vitro. Reverse transcription of ribonucleic acid from Pendred thyroid tissue and amplification by polymerase chain reaction of specific regions encoding the most important hormonogenic sites of Tg revealed a normal complementary DNA sequence corresponding to the first 100 amino acid residues in Tg's N-terminus. However, 3 of 35 clones of the 3'-region corresponding to the Tg C-terminus exhibited a deletion of nucleotides 7860-7994; this deletion was not present in any of the 150 clones from 7 other thyroids we examined. Four Pendred clones had a 2-nucleotide deletion at positions 7870-7871, a change that would result in a premature stop codon and was found in thyroids from several other subjects as well. We conclude that the messenger ribonucleic acid encoding the 3'-region of Tg can be abnormal in Pendred's syndrome. Some, but not all, of these changes also occur in other human thyroids. Further work is necessary to show if and how these alterations relate to defective hormone synthesis and goiter.

Pit-1/GHF-1 binds to TRH-sensitive regions of the rat thyrotropin beta gene.

Three regions within the 5'-flanking region of the TSH beta gene have A-T-rich sequences which have sequence similarity to binding sites for the pituitary-specific POU domain transcription factor Pit-1/GHF-1. These three regions have been termed TSH A (-274 to -258 bp), TSH B (-336 to -326 bp), and TSH C (-402 to -384 bp). TSH A and TSH C are able to confer 2-6-fold TRH stimulation to the heterologous viral thymidine kinase (tk) promoter in transient expression assays in GH3 pituitary cells; TSH C can confer a 3-10-fold increase in basal enhancer activity as well. TSH A, B, and C DNAs all bound Pit-1 from GH3 cell nuclear extracts, based on gel mobility shift analysis in which antibody against Pit-1 prevented the formation of specific DNA-GH3 nuclear protein complexes. TSH A and TSH C also each formed several additional DNA-nuclear protein complexes which were not observed with TSH B. Some of these complexes may contain Pit-1 as their formation was inhibited by the addition of Pit-1 antibody; other complexes, however, were not altered by antibody treatment. All three A-T-rich elements bound in vitro translated Pit-1, with calculated affinities of 360 (A), 125 (B), and 38 (C) nM, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Thyrotropin (TSH)-releasing hormone-responsive elements in the rat TSH beta gene have distinct biological and nuclear protein-binding properties.

Two TRH-responsive elements have been identified in the rat TSH beta gene by deletion/mutation analysis of the 5'-flanking region of the gene and transfection of TSH beta-luciferase constructs into the GH3 pituitary cell line. Biological responsiveness was confirmed by inserting synthetic oligonucleotides next to the heterologous viral thymidine kinase (tk) promoter in tk luciferase (tkLUC) constructs. Both DNA regions, termed TSH A (at -274 to -258 bp) and TSH C (-402 to -385 bp), have a high level of sequence similarity to binding sites for the POU domain pituitary transcription factor Pit-1/GHF-1. In transfection assays, the TSH A region had no basal enhancer activity, but did confer 3- to 6-fold TRH- and PMA-stimulated transcriptional responses to the tk promoter. The TSH C region conferred basal enhancer activity (3- to 10-fold above control tkLUC) as well as a 2- to 3-fold TRH or PMA response. Combinations of TSH A and TSH C elements conferred both enhancer activity and a TRH- or PMA-stimulated response, but more than two copies of the regions resulted in no further stimulatory effect. Both TSH beta gene regions bound to nuclear proteins from GH3 cells, as determined by gel retardation analysis. The TSH A region DNA formed three prominent DNA-protein complexes, ranging from slowly to rapidly migrating bands and with calculated affinities of 32, 0.5, and 208 nM, respectively. The TSH C region formed two major complexes, which corresponded on the basis of mobility to the most slowly and rapidly migrating complexes formed by TSH A, but with calculated affinities of 3.1 and 33 nM. TSH C also formed a rapidly migrating minor complex unique for this gene region. The more rapidly migrating complexes appeared to be specific to nuclear proteins from GH3 cells. Treatment of cells with TRH did not significantly alter the affinity of protein binding. Mutation of TSH A and TSH C DNA by T to G substitutions abolished the ability of the DNA to confer a TRH response and severely inhibited the ability of the DNA to bind to GH3 nuclear proteins. Thus, transcriptional regulation of the rat TSH beta gene by TRH is correlated with the ability of the two TRH-sensitive elements to bind nuclear proteins. The differences noted in basal enhancer activity or the degree of TRH responsiveness may be related to some unique proteins bound to each DNA or to the differences in affinity of binding of the proteins common to both elements.

Endosseous cylinder implants in severely atrophic mandibles.

A retrospective study was completed to assess the success rate of endosseous cylinder implants placed in mandibles that were 10 mm or less in maximum anterior height as measured from lateral cephalometric radiographs. Only implants that were located anteriorly between the mental foramina and loaded prosthetically for a minimum of 1 year were studied. Twenty-eight patients with a total of 130 Nobelpharma implants (forty-six 7 mm and eighty-four 10 mm) were included. The fixtures were evaluated following standard clinical criteria for success established for implants of this type. A total of 8 (two 7 mm and six 10 mm) of 130 implants failed, yielding an overall success rate of 94%. Major complications encountered included a complete mandibular fracture, a partial mandibular fracture, and a temporary bilateral mental nerve hypoesthesia.

Mandibular fractures through endosseous cylinder implants: report of cases and review.

These case reports and review focus on three mandibular fractures that occurred through endosseous cylinder implant sites. The first patient, and most likely the second, had osteoporotic changes that affected their already atrophic mandibles. The third patient probably had an area of deficient mineralization or poorly consolidated bone in the region where the fracture developed. These bony conditions increased the potential for fracture. Although the exact mechanism by which such fractures occur is not known, an examination of past research suggests that stress concentration at the mandibular defect prepared for implant placement is a probable explanation. The site of an implant that has not yet osseointegrated acts as a site of tensile stress concentration and ultimately an area of weakness. Consequently, this area of weakness in a mandible with decreased bone density or mineralization is more prone to applied functional forces. Repeated submaximal functional forces in an area of bony weakness, such as an endosseous implant site, may lead to a spontaneous fracture with no associated trauma. With these factors in mind, several extra precautions should be taken when implants are placed in thin or weak mandibles.

Life-threatening hemorrhage from placement of a dental implant.

This report focuses on a potentially fatal hemorrhage arising from dental implant placement in the mandible. Anatomic considerations of the lingual artery and its divisions in the floor of the mouth are discussed. In addition, various methods of controlling bleeding from the floor of the mouth are reviewed. The case presented is unusual in that intraoral ligation of the transected vessel was possible despite the presence of massive sublingual, submental, and submandibular hematomas as well as severely distorted anatomy. This case represents a severe complication resulting from a seemingly minor oral surgical procedure. Those performing endosteal implant placement should be knowledgeable in the management of such complications.

Levels of type I cAMP-dependent protein kinase regulatory subunit are regulated by changes in turnover rate during skeletal myogenesis.

The regulation of type I cAMP-dependent protein kinase during the differentiation of L6 myoblasts has been investigated in order to assess a possible role for this enzyme in the control of myogenesis. Immunoblot analysis showed that the levels of the type I cAMP-dependent protein kinase regulatory subunit (RI) increased 3-fold during differentiation. However, measurement of RI mRNA levels using an RI cDNA probe showed that this increase was not regulated transcriptionally. Determinations of the turnover rate of RI demonstrated that the subunit becomes 3-fold more stable in the differentiated cells. Therefore, it appears that the increase is due to a decrease in the rate of degradation of RI. The increase in both the amount and stability of RI could be reversed by treating myotubes with cAMP analogues or forskolin. Furthermore, during differentiation there was a large decrease in cAMP levels. It was, therefore, concluded that the increase in RI levels seen during differentiation is probably due to an increase in the stability of the subunit as a result of a decrease in intracellular cAMP concentrations.

Defective binding of 3-methylcholanthrene to the Ah receptor within C3H/1OT1/2 clone 8 mouse fibroblasts in culture.

C3H/1OT1/2 clone 8 mouse fibroblasts (C3H/1OT1/2 cells) exhibit induction of aryl hydrocarbon hydroxylase (cytochrome P1-450) when exposed in culture to benzo(a)pyrene, benz(a)anthracene or 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), but do not display the induction response when treated with 3-methylcholanthrene (MCA), the classical inducer of cytochrome P1-450. Induction of cytochrome P1-450 is regulated by the Ah receptor which initially binds inducing chemicals in the cytoplasm, after which the inducer x receptor complex translocates into the nucleus. Cytosolic and nuclear forms of the Ah receptor can be detected in C3H/1OT1/2 cells using [3H]TCDD as the radioligand in culture, but specific Ah receptor binding is not detectable within C3H/1OT1/2 cells incubated with [3H]MCA. In contrast, in Hepa-1c1 cells, which exhibit cytochrome P1-450 induction when treated with MCA, cytosolic and nuclear Ah receptor can be detected by incubation of the cells either with [3H]MCA or with [3H]TCDD. Nonradioactive MCA is able to compete with [3H]TCDD for Ah receptor sites in C3H/1OT1/2 cells, but the relative potency of MCA as a competitor is lower within C3H/1OT1/2 cells than in C3H/1OT1/2 cytosol during extracellular incubation. Specific binding of [3H]MCA to Ah receptor can be detected by incubation of [3H]MCA with C3H/1OT1/2 cytosol outside the cell. The selective loss of response to MCA as a cytochrome P1-450 inducer (while retaining response to other inducers) appears to be due to defective interaction of MCA with the Ah receptor within the intracellular environment. The specific molecular alteration which makes the MCA x receptor complex ineffective within C3H/1OT1/2 cells is unknown. Some fibroblast lines other than C3H/1OT1/2 also selectively fail to respond to MCA; thus, this variation in Ah receptor function may not be due to a mutational change in the Ah regulatory gene which codes for the Ah receptor.

Aryl hydrocarbon hydroxylase activity in mouse, rat, and human mammary tumors.

Aryl hydrocarbon hydroxylase (AHH) activity was measured in microsomes from chemically induced and spontaneous mammary tumors of mice and rats and in 213 human breast tumors. Basal enzyme activities [pmol 3-hydroxybenzo(a)pyrene per mg protein per min] ranged from 0.05 to 0.5 for rat, 0.05 to 10 for mouse, and 0 to 40 for human tumors. For comparison, mean liver AHH activities were 13 in untreated rats and 100 in untreated mice. Thus, some human breast tumors had AHH activity exceeding that in rat liver. Injection of 80 mg beta-naphthoflavone per kg into tumor-bearing C3H/HeJ mice or Sprague-Dawley rats increased AHH activity to 10- to 70-fold over basal levels; there was no significant AHH induction in tumors from genetically "nonresponsive" DBA/2J or RF/J mice treated with beta-naphthoflavone, alpha-Naphthoflavone in the incubation flask inhibited AHH activity in some human breast tumors and stimulated activity in others, probably reflecting the presence of multiple forms of cytochrome(s) P-450 in the human tumor population. AHH activity in human tumors was not correlated with their estrogen receptor content. Since several drugs used in cancer treatment are substrates for polysubstrate monoxygenases, high levels of AHH activity in some human tumors may play a role in their response to chemotherapy.