Search PubMed⌕ Search

Biomedical subjects

C Henry

Publications and source records attributed to C Henry.

At least 109 records · Page 6Linked to original sources
PubMed1989

Comparison of effective toxicant biotransformation by autochthonous microorganisms and commercially available cultures in the in situ reclamation of abandoned industrial sites.

Biotransformation and biodegradation of polycyclic aromatic hydrocarbons by the subsurface autochthonous microflora collected from an abandoned petroleum refinery site was investigated. In addition, the inoculation of a commercially available blend of bacterial cultures, with known ability to degrade polycyclic aromatics, was evaluated. This supplemental addition of select microorganisms has been referred to by commercial interests as "bioaugmentation". Their biodegradative potential was evaluated using laboratory mesocosms (simulations) containing a predetermined optimal waste loading rate based on % oil and grease, mixed with predetermined optimal loading rates of clay and river silt materials. The waste consisted primarily of aliphatic and aromatic hydrocarbons found in buried sludges and abandoned lagoons. All mesocosms received nutrient amendment without additional energy sources. Experimental mesocosms were inoculated with adapted indigenous microflora and/or commercial strains. Microbial ATP, microbial diversity, and related enzyme assays were used to establish the detoxification efficiency of the experimental microflora. Quantitative toxicant concentrations and transformations were documented by GC/MS data. Information will be presented mainly on the kinetics of toxicant biotransformation processes to identify "bioaugmentation" contribution and relevancy in the recovery of abandoned polluted sites.

Bacteria↗
PubMed1989

[In vitro determination of the sensitivity of mycobacteria to fluoroquinolones].

In vitro activity of four fluorinated quinolones: pefloxacin, norfloxacin, ciprofloxacin, ofloxacin were determined against various clinical isolates of mycobacteria. The method of agar dilution was used, seventy strains of ten species were tested: Mycobacterium tuberculosis (25), Mycobacterium bovis (5), Mycobacterium africanum (2), BCG (5), Mycobacterium kansasii (6), Mycobacterium marinum (5), Mycobacterium avium (11), Mycobacterium xenopi (6), Mycobacterium chelonae (3), Mycobacterium fortuitum (2). Except for Mycobacterium avium and Mycobacterium chelonae (CMI 100% greater than 8 mg/l) fluorinated quinolones showed activity against tested mycobacteria (CMI 100% less than or equal to 8 mg/l). Ofloxacin and ciprofloxacin where found to be the most active. Their activity against the different strains of Mycobacterium tuberculosis was unrelated to their susceptibility or resistance to the antituberculous drugs.

Anti-Infective Agents↗
PubMed1988

Evidence that the Abdominal-B r element function is conferred by a trans-regulatory homeoprotein.

The Abdominal-B gene is a homeotic gene located in the distal-most region of the bithorax complex (BX-C). Based on complementation analysis it has been proposed that the gene contains two separable genetic elements, called the m and r elements. The r element has a chiefly regulatory function confined to parasegment 14. In a reverse Northern screen of the distal-most BX-C DNA, we found four distinct areas that are transcribed in the embryo. One of the transcripts spans a large genomic region which, upon disruption by rearrangement breakpoints, causes loss of r element function. This transcript is expressed in the early embryo in a single domain apparently corresponding to parasegment 14. We propose that the small homeoprotein encoded by the transcript acts as a trans-regulator to confer r element function.

Amino Acid Sequence↗
PubMed1988

Mapping by in vitro constructs of the P100gag-mil region, accounting for induction of chicken neuroretina cell proliferation.

The v-mil oncogene of the avian retrovirus MH2 is expressed as a fusion protein with viral gag determinants in infected cells. This P100gag-mil protein accounts for the proliferation of chicken embryo neuroretina cells (CNR) induced by MH2 in vitro. We constructed a series of mutants by in-frame deletions in different parts of the gag and mil domains and tested their ability to induce CNR growth. We show that gag sequences, as well as 200-base-pair 5' mil sequences, were not required to induce such a proliferation. However, gag sequences seem to contribute to a full proliferation of growing CNR. In contrast, deletions in the kinase domain abolish this induction. In particular, by deleting only 9 nucleotides localized around the unique SphI site of v-mil, we produced a totally inactive mutant (BalSp). This mutant directs the synthesis of a v-mil protein lacking the dipeptide Tyr-Leu, which is conserved in almost all the members of the large protein kinase family, and a histidine residue highly conserved in Ser-Thr protein kinase members.

Animals↗
PubMed1988

Alternative splicing within the chicken c-ets-1 locus: implications for transduction within the E26 retrovirus of the c-ets proto-oncogene.

Two overlapping c-ets-1 cDNA clones were isolated which contained the alpha and beta genomic sequences homologous to the 5' end of v-ets not detected in the previously described c-ets RNA species or proteins. Nucleotide sequencing demonstrated that these cDNAs corresponded to the splicing of alpha and beta to a common set of 3' exons (a through F) already found in the p54c-ets-1 mRNA. They contained an open reading frame of 1,455 nucleotides which could encode a polypeptide of 485 amino acids with a predicted molecular mass of 53 kilodaltons. However, when expressed in COS-1 cells, the cDNAs directed the synthesis of a protein with an apparent molecular mass in sodium dodecyl sulfate-polyacrylamide gel electrophoresis of 68 kilodaltons, p68c-ets-1, comigrating with a protein expressed at low levels in normal chicken spleen cells. These two proteins were shown to be identical by partial digestion with protease V8. Northern (RNA) blot hybridization analysis with the p68c-ets-1 -specific sequence and RNase protection experiments showed that the corresponding mRNA was expressed in normal chicken spleen and not in normal chicken thymus or in various T lymphoid cell lines. Thus, two closely related proteins, having distinct amino-terminal parts, are generated within the same locus by alternative addition of different 5' exons, alpha and beta or I54, respectively, onto a common set of 3' exons (a to F). Finally, we demonstrate that an aberrant splicing event between a cryptic splice donor site in c-myb exon E6 and the normal splice acceptor site of c-ets-1 exon alpha involved in the genesis of the E26 myb-ets sequence.

Animals↗
PubMed1988

Alternative splicing of RNAs transcribed from the chicken c-mil gene.

Two distinct c-mil-related cDNA clones have been isolated from a chicken embryo cDNA library. Results presented here show that the single chicken c-mil gene is coding for two c-mil mRNA species, different by at least 60 base pairs and generated by an alternative splicing mechanism. These mRNA molecules can be translated into two distinct proteins of 73 and 71 kilodaltons.

Amino Acid Sequence↗
PubMed1988

Neuroanatomical study of Galen's anastomosis (nervus laryngeus) in the dog.

To further knowledge of the laryngeal nerves, the nerve fibers of Galen's anastomosis were studied using two neuroanatomical methods, namely nerve degeneration and horseradish peroxidase labeling. It is demonstrated that the superior laryngeal nerve forms part of the tracheal and esophageal nervous system. The value of the results in relation to physiological laryngeal studies and to human laryngeal diseases is discussed.

Animals↗
PubMed1988

Vocal cord abduction rehabilitation by nervous selective anastomosis.

Laryngeal reinnervation procedures were performed on 15 dogs. An anastomosis was performed between a selected motor branch of the ansa hypoglossi and the posterior cricoarytenoid nerve. The results were analyzed endoscopically, electromyographically, and histologically. Results were satisfactory in 12 cases. The methods and results have been compared with those obtained using other reinnervation techniques.

Anastomosis, Surgical↗
PubMed1988

Cloning and expression of chicken p54c-ets cDNAs: the first p54c-ets coding exon is located into the 40.0 kbp genomic domain unrelated to v-ets.

We have isolated cDNA clones of chicken c-ets mRNA the longest of which, designated pCk E54A, contained approximately 2.0 kb of a c-ets mRNA species. Nucleotide sequencing of this clone revealed a single long open reading frame, extending from the first ATG codon (nucleotide +1) to a TGA termination codon at nucleotide 1324. The predicted translation product contains 441 amino acid residues and its molecular weight is 48 kd. Expression in COS-1 cells of this clone resulted in the synthesis of polypeptides immunologically indistinguishable from the authentic p54c-ets after one-dimensional gel electrophoresis. Comparison of the nucleotide sequence of this cDNA to that of v-ets of avian acute leukemia virus E26 showed that both sequences are almost colinear with the exception of five point mutations but present striking differences in their 5' and 3' parts. 79 nucleotides downstream of the first ATG codon in c-ets cDNA are not found in the 5' part of v-ets where they are replaced by 223 different nucleotides. The 3' parts of v-ets and the coding region of the chicken c-ets cDNAs are also different: the last 13 codons of the cDNA are replaced by 16 different codons in v-ets. Thus our results precisely define the structural differences between the ets encoded domain of E26 viral transforming protein (P135 gag-myb-ets) and the normal cellular protein p54c-ets expressed at high levels in chicken thymocytes and bursal lymphocytes. They also suggest the possibility of alternative splicing of different 5' exons to a common set of 3' exons.

Amino Acid Sequence↗
PubMed1987

Directed fusion in hybridoma production.

We have attempted to increase the frequency of azobenzene arsonate-specific hybrids by bridging specific B cells to the myeloma partner cells prior to polyethylene glycol-induced fusion. Bridging was accomplished by prelabeling the B cells with avidin-labeled antigen and incubating them with myeloma cells that had been modified directly with biotin. We have tested this system of hybridization with B cells from normal mice, and mice undergoing both primary and secondary responses. We found that the method is fruitful for IgG-secreting hybridomas of moderately high affinity.

Antibody Affinity↗
PubMed1987

Effects of alpha and theta toxins from Clostridium perfringens on human polymorphonuclear leukocytes.

Two toxins, alpha (phospholipase C) and theta (oxygen-labile hemolysin), were purified from Clostridium perfringens type A and assayed for toxic effects on human polymorphonuclear leukocytes (PMNLs). Crude preparations containing both toxins totally inhibited chemotaxis and chemiluminescence responses of PMNLs and reduced PMNL viability. Purified alpha toxin did not alter PMNL viability, chemotactic responsiveness, or morphology but did enhance opsonized zymosan-induced PMNL chemiluminescence over a wide range of toxin concentrations. theta Toxin, at 12.5 hemolytic units (HU) per 10(5) PMNLs, reduced cell viability and induced marked PMNL morphological changes. Concentrations of theta toxin between 4 and 32 HU per 10(5) PMNLs inhibited PMNL chemiluminescence in a dose-dependent manner, whereas a lower concentration enhanced the PMNL chemiluminescent response to opsonized zymosan. Effects on chemotaxis were also dose dependent. Increased PMNL random migration was observed at a concentration of theta toxin of 0.06 HU per 2.5 X 10(5) PMNLs (P less than .05), whereas concentrations of greater than 0.08 HU per 2.5 X 10(5) PMNLs reduced both directed and random migration (P less than .05).

Bacterial Toxins↗
PubMed1987

Concept of the person: introduction to the health professionals' curriculum.

This paper deals with the concept of the person and its necessity in health care and health curricula. Specifically it looks at aspects of both the biological and social sciences. Further, there is some suggestion that for caring professionals in particular the concept of the person requires more analysis than purely a 'common sense' everyday meaning and use, and that there is some requirement for sorting out and understanding the difference and the interconnections of the two terms 'human' and 'person'. This first proposal will be followed by a further paper that discusses in more detail the distinction between the two terms and the moral issues that derive from the centrality of use of the concept of the person by the health professions.

Biology↗
PubMed1987

Persons and humans.

This paper examines the concept of a person, in particular in terms of its relationship with the concept of human. It discusses the function of person as a concept and the purpose of making a distinction between human and person and allocating all the value connotations of the two terms to person. An examination of possible definitions of person follows, divided into those dealing mainly in intrinsic features, centrally rationality and self consciousness, and those dealing with the concept as it functions as a relation in terms of role or status. Finally, possible accounts of the relation between human and person are considered and 'potential' is identified as a way of linking the two.

Humans↗
PubMed1987

Physical and aerodynamic features of the Bordeaux voice prosthesis.

Performance of a voice prosthesis, used to restore speech in patients following total laryngectomy, was evaluated by measuring in vitro, as well as in vivo, airflow resistances. The pressure-flow characteristics of the device were analyzed using the standard pressure-flow diagram (to calculate airway resistance) and a Moody plot (to determine the different flow patterns). The flow rate and the pressure drop were measured with a Fleisch pneumotachograph and a variable reluctance transducer, respectively. Total device resistances were found in the range of 34-50 cm H2O/L/s when the flow-rates ranged from 0.05 to 0.35 L/s. Comparison of these resistances with those of other commercially available devices showed that our voice prosthesis had the lowest resistance.

Airway Resistance↗