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Biomedical subjects

C Thomas

Publications and source records attributed to C Thomas.

At least 397 records · Page 22Linked to original sources
PubMed1988

Umbilical cord pseudocyst in trisomy 18.

Prenatal diagnosis of cord defects by means of ultrasound examination is possible and highly accurate. Although this is a rare pathological finding, we report two cases in which umbilical cord pseudocysts were associated with trisomy 18. These observations underscore the need of umbilical blood sampling for establishing the karyotype in fetuses with such umbilical cord anomalies and the importance of careful examination of placentas and infants born with such defects.

Adult↗
PubMed1988

Characterization of two clones isolated from the TC-1 murine marrow stromal cell line: growth factor and retrovirus production and physical support of hemopoiesis.

We previously reported the isolation of an adherent murine marrow cell line termed TC-1, and the initial characterization of two subclones derived from this line. In this study we report a further characterization of two subclones from the non-cloned TC-1 cell line. One subclone, TC-1-C-3, consisted of large, slow-growing syncytial polypoid cells that grew to relatively low saturation densities, did not form colonies in soft agar and showed desmosome-like junctions. The other subclone, TC-1-C-11, consisted of smaller, rapidly growing fibroblast-like diploid cells which showed anchorage-independent growth in soft agar. Both these subclones produced growth factors which stimulated giant macrophage colonies in soft agar culture in vitro, but only the TC-1-C-3 subclone produced a retrovirus, whose source was most likely the endogenous ecotropic Emv-2 provirus present in chromosomal DNA in C57BL mice. This retrovirus from the TC-1-C-3 subclone did not appear capable of transforming TC-1-C-11 cells. Together, these data suggest that TC-1-C-3 cells have a special capacity for supporting hemopoiesis. The question of whether the mechanism of this support relates to an intrinsic property of the cell or is possibly related to retrovirus production remains unanswered.

Animals↗
PubMed1988

Partial purification and characterization of phosphatidylinositol kinase from bovine brain.

Purification of Phosphatidylinositol (PI) kinase was attempted from bovine brain. A seven step purification protocol increased the specific activity 100 x but attempts at further purification were unsuccessful. Labeling of the partially purified PI kinase with the ATP analog fluorosulfonylbenzoyl adenosine reproducibly identified three bands on polyacrylamide gel electrophoresis of 76 K, 45 K, and 29 K, one of which likely represents PI kinase. Kinetic studies showed a Km of 17 microM for ATP, 0.02 mg/ml for PI and a Vm of 1830 pmol/min/mg protein for ATP and 820 pmol/min/mg protein for PI.

1-Phosphatidylinositol 4-Kinase↗
PubMed1988

Coping and the outcome of stoma surgery.

A prospective 12 month study of 106 subjects who underwent stoma surgery was conducted and has been described previously. Coping responses to the underlying diagnosis and to the stoma itself were assessed at 3 and 12 months post operatively and are related to the outcome 3 years after the operation. Difficulty coping with the stoma itself was a greater determinant of later psychiatric disturbance than difficulty in coping with the illness. Physical outcome, in those with colorectal carcinoma, was influenced by coping strategies only in the males, denial over diagnosis was significantly associated with poor outcome whereas fighting spirit over the stoma was associated with a good outcome.

Adaptation, Psychological↗
PubMed1988

Electrocardiographic body surface potential maps of the QRS and T of normal young men. Qualitative description and selected quantifications.

A qualitative and quantitative analysis of the Body Surface Potential Maps (BSPM) of 40 young men, ages 19-41, is presented utilizing a 180 electrode system, with 135 anterior leads and 45 posterior leads. Evidence for epicardial right ventricular breakthrough was demonstrated in 36/40 at 27.9 +/- 6.8 ms, whereas our previous studies on normal children (average age 12.5 years) have demonstrated evidence for epicardial right ventricular breakthrough at 25.0 +/- 8.9 ms. The peak-to-peak magnitude at maximal potential (at 42.3 +/- 4.8 ms) was not significantly different from that of the children (4,430 +/- 1,165 microV), and the peak-to-peak magnitude of ST-T was virtually the same as that of the children (1,182 +/- 376.2 microV). The terminal activation pattern of late QRS on the body surface map appeared in the true posterior, anterior superior, posterior right superior and/or right anterior superior positions, in order of frequency. There were other regions appearing less frequently. In contrast, this pattern in children was seen only in the anterior superior, right anterior superior, posterior right superior, and true posterior in order of frequency. In 18/40, the body surface manifestation of repolarization was seen an average of 9.4 +/- 4.8 ms before the end of the QRS. A new pseudocolor display with 31 color levels representing body surface potentials allowed excellent resolution of isopotential detail.

Adult↗
PubMed1988

The effect of date of cut and barley substitution on gain and on the efficiency of utilization of grass silage by growing cattle. 1. Gains in live weight and its components.

1. A primary growth of perennial ryegrass (Lolium perenne) was cut early or late to produce silages of high and low digestibility. The crops were wilted for 2-4 h and preserved with formic acid at 2.4 litres/t fresh weight. The resulting silages were well preserved with a pH of 3.9 and 3.8, lactic acid content of 108 and 73 g/kg dry matter (DM) and total nitrogen content of 24.6 and 18.4 g/kg DM for early- and late-cut silage respectively. 2. Forty-two British Friesian male castrates (steers) initially 12 months of age and 305 kg live weight (LW) were used, of which ten were slaughtered at the start of the experiment. The remaining steers were divided into four groups of eight animals and were given the early-cut silage alone (H) or the late-cut silage alone (L) or with barley at either 280 (LC1) or 560 (LC2) g DM/kg total DM. The intake of total DM was restricted to a daily allowance of 18 g DM/kg LW and the steers were slaughtered in two groups after 119 and 140 d on experiment. 3. Both earlier cutting of herbage and substitution of late-cut silage with barley significantly (P less than 0.001) increased the apparent digestibility of gross energy (H0.748, L0.619, LC10.668, LC20.705), whereas earlier cutting increased the digestibility of acid-detergent fibre from 0.638 (L) to 0.777 (H) and substitution with barley resulted in a significant (P less than 0.001) depression to 0.595 (LC1) and 0.519 (LC2). Substitution of late-cut silage with barley significantly (P less than 0.001) increased metabolizable energy (ME) intake from 58.9 (L) to 69.5 MJ/d (LC2) and crude protein (N x 6.25; CP) intake from 688 (L) to 779 g/d (LC2), but the highest intakes of ME and CP (73.5 MJ/d and 952 g/d respectively) were achieved with the early-cut silage. 4. Earlier cutting resulted in significant (P less than 0.001) increases in body-weight gain from 292 to 696 g/d, fat gain from 121 to 260 g/d, protein gain from 31.1 to 86.9 g/d and energy retention from 5.5 to 12.2 MJ/d for silages L and H respectively. However, substitution of the late-cut silage with barley increased gains to a greater extent. Thus, empty-body gain was increased to 552 and 800 g/d, fat gain to 189 and 302 g/d, protein gain to 76 and 116 g/d and energy retention to 9.2 and 14.6 MJ/d for diets LC1 and LC2 respectively.(ABSTRACT TRUNCATED AT 400 WORDS)

Animal Feed↗
PubMed1988

The effect of date of cut and barley substitution on gain and on the efficiency of utilization of grass silage by growing cattle. 2. Nutrient supply and energy partition.

1. The effect of harvesting date of perennial ryegrass (Lolium perenne) on the nutritive value of the resultant silage and the effect of substitution of late-cut silage with barley was examined in growing cattle. The diets comprised early-cut (H) and late-cut (L) silage offered alone or with 280 (LC1) or 560 (LC2) g rolled barley/kg total dry matter (DM) substituted for late-cut silage. 2. Both silages were prepared with the addition of formic acid (850 milligram; 2.4 litres/t fresh weight) to a partially wilted crop, and were judged to be well fermented (pH 3.9, 3.8) with lactic acid contents of 108 and 73 g/kg DM, total nitrogen contents of 24.6 and 18.4 g/kg DM and ammonia-N contents of 121 and 124 g/kg total N (values for early- and late-cut silages respectively). 3. Two experiments were conducted to measure duodenal non-NH3-N (NAN) supply in relation to N intake on the four diets (feeding level 18 g DM/kg live weight (LW] and to examine the partition of the metabolizable energy (ME) supply from the four diets using open-circuit indirect calorimetry (three feeding levels, 14, 17 and 20 g DM/kg LW). The experiments were undertaken with eight and nine Friesian male castrates respectively with a mean starting weight of 300 kg and age 12 months. The animals used in Expt 1 had been previously fitted with cannulas into the dorsal rumen and the proximal duodenum. 4. NAN supply was significantly higher on diet H than all other diets which were similar irrespective of the level of barley inclusion. Mean ME contents (MJ/kg DM) of the two silages differed markedly (H 11.9, L 9.7) and barley addition (LC1 and LC2) restored values to 10.7 and 11.1 MJ/kg DM respectively. Estimated NAN absorption in relation to energy supply was significantly higher for diet H (1.47 g/MJ ME) than for all other diets (mean 1.25 g/MJ ME). 5. Partition of ME supply using conventional linear analysis indicated dietary differences with respect to estimated ME for maintenance (L greater than H, LC1 and LC2) and efficiency of utilization of ME supplied above maintenance (L greater than H, LC1 and LC2), but difficulties in biological interpretation of these findings led to the use of exponential curve analysis. This provided an improved description of the findings, and whilst dietary differences were apparent, none were statistically significant. It was concluded that a single exponential equation could be used satisfactorily to describe all values.(ABSTRACT TRUNCATED AT 400 WORDS)

Animal Feed↗
PubMed1988

Neurologic outcome in rats following incomplete cerebral ischemia during halothane, isoflurane, or N2O.

Using rats in which incomplete cerebral ischemia was induced, the authors evaluated the effects of halothane (H) and isoflurane (I) on neurologic outcome compared to nitrous oxide (N2O) controls. Incomplete cerebral ischemia was produced by right carotid artery occlusion combined with hemorrhagic hypotension. Neurologic outcome was evaluated using a graded deficit score from 0 to 5 (0 = normal, 5 = death associated with stroke). Two levels of cerebral ischemia were tested. At moderate ischemia with hypotension of 30 mmHg, an FIO2 of 0.3, and ischemic periods of 30 or 45 min, N2O produced a deficit of 4.7-5.0 and a mortality rate of 90-100%. In contrast, halothane (1 MAC) and isoflurane (1 MAC) resulted in similar deficit scores (H = 1.1-1.8, I = 1.4-1.6) and mortality rates (H = 17-30%, I = 17-20%). Cerebral blood flow (CBF) measured with radioactive microspheres showed a 60-65% decrease in the ischemic hemisphere at this level of hypotension. With severe ischemia with hypotension = 25 mmHg, FIO2 = 0.2, and a 30-min period of ischemia, deficit scores increased to 3.0 and 3.9 with 1 MAC halothane and 1 MAC isoflurane, respectively. Mortality rates also increased to 40% with halothane and 70% with isoflurane. Increasing the concentration of halothane or isoflurane to 2 MAC did not significantly improve outcome. Brain histology demonstrated extensive neuronal damage in striatal, hippocampal, and neocortical regions of N2O control treated rats, and less damage with little difference between H- and I-treated rats at each level of ischemia.(ABSTRACT TRUNCATED AT 250 WORDS)

Anesthesia, Inhalation↗
PubMed1988

Hospital and ambulatory service use by the urban elderly under different health care delivery systems.

For a sample of elderly persons living in an urban community, patterns of use of health-care services varied according to whether or not respondents identified one of three fee-for-service delivery systems as their primary source of care: a hospital, a private physician, or a medical group practice. Differences in utilization patterns persisted even when population health and socioeconomic characteristics were controlled, and are attributable either to differences in system structure or to the population's behavioral response to these systems of care. As expected, the health variables, as well as whether or not persons had a source of care, were the most important factors in explaining aggregate inpatient and ambulatory care visits. In addition, particular sources of care and socioeconomic variables were significant in explaining duration of time spent in hospital and types of ambulatory care visits. Policy implications of these and related findings are discussed.

Aged↗
PubMed1988

The nucleotide sequence of Staphylococcus aureus plasmid pT48 conferring inducible macrolide-lincosamide-streptogramin B resistance and comparison with similar plasmids expressing constitutive resistance.

The complete nucleotide sequence of a naturally occurring Staphylococcus aureus plasmid, pT48 (from S. aureus strain T48), has been determined. The 2475 bp plasmid confers inducible resistance to macrolide-lincosamide-streptogramin B (MLS) type antibiotics. It is similar to the constitutive MLS resistance plasmid, pNE131, from Staphylococcus epidermidis and shows homology with S. aureus plasmids pSN2 and pE194. It contains a palA structure homologous to that on S. aureus plasmid pT181. The open reading frame, ORF B, within the pSN2 homologous region has a frameshifted C-terminus, relative to pNE131, resulting in a smaller, 158 amino acid putative polypeptide. The pE194 homologous region has the ermC resistance determinant and retains the leader region, deleted in pNE131, required for inducible expression of an adenine methylase. Another naturally occurring S. aureus strain, J74, shows constitutive resistance to erythromycin and contains a small plasmid, pJ74, which is similar to pNE131 but with a different deletion in the leader sequence. The results are consistent with the translational attenuation model for ermC expression.

Anti-Bacterial Agents↗
PubMed1988

[Angiodynography: initial experiences with a new sonographic method].

Angiodynography is a further development of Duplex sonography and a new, non-invasive imaging method that places no stress on the patient and enables simultaneous sonomorphological diagnosis of the organs and soft parts as well as their blood supply. Experience to date has shown that the angiodynographic vascularisation pattern is a diagnostic criterion in the clarification of circumscribed thyroid changes. If thyroid findings appear to be unclear, e.g. in case of scintigraphic cold nodes, angiodynography can be used with success as a complementary method. It can also help to classify findings in focal lesions of the liver. Information on functional parameters are supplied for differentiating arterial and venous vascular processes. They are easier to apply, more rapid and more accurate than with Duplex sonography. A drawback is the limited depth of penetration (5 MHz transducer). Angiodynography can be appreciated quickly and easily. It appears to be not only a complement to conventional examination methods but may even replace established diagnostic methods in solving certain problems.

Color↗