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H Jones

Publications and source records attributed to H Jones.

At least 145 records · Page 8Linked to original sources
PubMed1990

Running, osteoarthritis, and bone density: initial 2-year longitudinal study.

PURPOSE: The purpose of this study was to present the 2-year follow-up results examining associations of repetitive long-term physical impact (running) with osteoarthritis and osteoporosis in 34 members of a running club now aged 52 to 74 years and 34 matched control subjects. PATIENTS AND METHODS: Roentgenograms of the hands, lateral lumbar spine, and knees were assessed in pairs (1984 and 1986) without knowledge of running status. Computerized scans of the first lumbar vertebrae were obtained to quantify bone mineral. RESULTS: A decrease in bone density over the 2-year period was statistically significant for nearly all subjects, especially for runners who decreased their running habits. At the 2-year follow-up, runners maintained greater bone density. Progression of the roentgenographic scores for osteoarthritis demonstrated a statistically significant increase in almost all groups in this normative population over the 2-year period. Female runners had more spur formation in the weight-bearing knee roentgenograms than did control subjects. CONCLUSION: With the possible exception of spur formation in women, running did not appear to influence the development of radiologic osteoarthritis in the populations studied.

Aged↗
PubMed1990

Investigation of expression of 5T4 antigen in cervical cancer.

A monoclonal antibody detecting amniotrophoblastic antigen 5T4 has shown reactivity against various neoplastic cell lines and tumour specimens but with a relatively restricted normal tissue expression. This antibody has been investigated as a potential indicator of premalignant changes identified as cervical intra-epithelial neoplasia and malignant cervical lesions using immunohistochemistry on frozen tissue biopsies. The basal cells of normal cervical stratified epithelium exhibited faint staining, but a general increase in intensity and extent of specific labeling of this tissue was seen from the first premalignant stage through to carcinoma. In most cases, this was in accordance with the distribution of dysplastic cells, and was accompanied by increased specific staining of the stromal tissue. All invasive squamous carcinomas of the cervix were 5T4 antigen positive. Common inflammatory non-malignant diseases did show a certain degree of epithelial and stromal reactivity. These results, showing 5T4 reactivity with neoplastic and pre-neoplastic lesions, may provide a quantitative basis for its potential use as a tumour marker in the immunochemical detection on immunoassay of cervical cancer.

Antigens, Neoplasm↗
PubMed1990

Rectal bismuth subsalicylate as therapy for ulcerative colitis.

In a prospective open study, 15 patients with ulcerative colitis which was unresponsive to conventional therapy were treated with enemas containing bismuth subsalicylate (700 or 800 mg b.d.). Nine out of the 15 patients showed a significant clinical response, and 6 had gone into complete clinical remission after 8 weeks treatment. Sigmoidoscopoic appearances of the rectal mucosa showed improvement in 9 out of 15 patients at 2 weeks, and 11 out of 15 at 8 weeks. The mucosa appeared sigmoidoscopically normal in 6 out of 15 at 8 weeks. It proved possible to reduce the oral prednisolone dosage from a median of 15 mg/day (range 10 to 35 mg/day) to 6 mg/day (range 0 to 18 mg/day) after 8 weeks of treatment; 5 patients were no longer taking oral steroids at this time. Rectal bismuth subsalicylate appears likely to be an effective therapy in ulcerative colitis and controlled trials are now required.

Administration, Rectal↗
PubMed1990

Differing actions of dietary protein and enalapril on renal function and proteinuria.

Albuminuria (UalbV) increases in proportion to dietary protein in rats with passive Heymann nephritis. To determine whether a similar relationship existed in normal animals, 14 normal rats were switched from an 8.5% protein diet (LP) to a 40% protein diet (HP). Initially UalbV and glomerular filtration rate (GFR) increased in parallel, but GFR ceased to increase after 48 h while UalbV continued to increase, causing a significant increase in fractional renal clearance of albumin (FCalb). In contrast, HP for 4 days caused only a transient increase in GFR in nephrotic rats but effected a threefold sustained increase in UalbV. Pretreatment of nephrotic rats with enalapril blunted but did not entirely prevent the increase in UalbV after switching to HP and did not affect the increase or subsequent decline in GFR. Treatment with enalapril for 10 days reduced UalbV and FCalb in nephrotic rats fed either LP or HP. The similar pattern of changes in urinary albumin excretion in normal and nephrotic rats after dietary protein augmentation suggests that dietary protein may modify UalbV by the same process in both normal and nephrotic animals. The increases in UalbV and GFR resulting from dietary protein augmentation represent parallel but independent processes, since only the proteinuric response is modified by converting enzyme inhibition. Dietary protein restriction and converting enzyme inhibition exert an additive effect to reduce UalbV.

Albuminuria↗
PubMed1989

Function of plastid mRNA 3' inverted repeats. RNA stabilization and gene-specific protein binding.

Plastid protein coding regions in plants are generally flanked by 3' inverted repeat (IR) sequences. In a previous work (Stern, D. B., and Gruissem, W. (1987) Cell 51, 1145-1157), we have shown that their role may be in RNA stabilization and as a processing signal that establishes the mature mRNA 3' end. In this report we have investigated the stability and protein interaction of chloroplast mRNA 3' IR-RNA sequences in more detail. Progressive deletions into the 3' IR-RNA sequences for the chloroplast cytochrome b6/f subunit IV (petD) mRNA reduce the stability of the RNA, indicating that the potential to form a stem/loop is a minimum requirement for petD 3' IR-RNA stability in vitro. Specific point mutants also destabilize the processed 3' IR-RNA, suggesting an important role for the primary sequence. Gel mobility shift and UV-cross-linking analysis has shown that 3' IR-RNAs of petD and two other chloroplast mRNAs (rbcL and psbA) interact with proteins in vitro. Comparison of the bound petD 3' IR-RNA proteins with proteins that bind to rbcL and psbA reveals that binding of certain proteins is gene-specific. Also, precursor and processed petD 3' IR-RNAs bind different sets of proteins. A single nucleotide transversion (T----A) near the base of the stem eliminates the binding of a 29-kDa protein to the petD 3' IR-RNA precursor. We discuss the possible role of 3' IR-RNA-protein interactions in plastid mRNA 3' end maturation and differential mRNA stability.

Base Sequence↗
PubMed1989

Transient gene expression in electroporated Solanum protoplasts.

Electroporation was used to evaluate parameters important in transient gene expression in potato protoplasts. The protoplasts were from leaves of wild potato Solanum brevidens, and from leaves, tubers and suspension cells of cultivated Solanum tuberosum cv. Désirée. Reporter enzyme activity, chloramphenicol acetyl transferase (CAT) under the control of the cauliflower mosaic virus (CaMV) 35S promoter, depended on the field strength and the pulse duration used for electroporation. Using field pulses of 85 ms duration, the optimum field strengths for maximum CAT activity were: S. brevidens mesophyll protoplasts--250 V/cm; Désirée mesophyll protoplasts--225 V/cm; Désirée suspension culture protoplasts--225 V/cm; and Désirée tuber protoplasts--150 V/cm. The optimum field strengths correlated inversely with the size of the protoplasts electroporated; this is consistent with biophysical theory. In time courses, maximum CAT activity (in Désirée mesophyll protoplasts) occurred 36-48 h after electroporation. Examination at optimised conditions of a chimaeric gene consisting of a class II patatin promoter linked to the beta-glucuronidase (gus) gene, showed expression (at DNA concentrations between 0-10 pmol/ml) comparable to the CaMV 35S promoter in both tuber and mesophyll protoplasts. At higher DNA concentrations (20-30 pmol/ml) the patatin promoter directed 4-5 times higher levels of gus expression. Implications and potential contributions towards studying gene expression, in particular of homologous genes in potato, are discussed.

Chloramphenicol O-Acetyltransferase↗
PubMed1989

Fertility decline in Mauritius: the role of Malthusian population pressure.

Mauritius provides 1 of the outstanding cases of modern fertility reduction in the Third World, yet there has been little analysis and virtually no comparative assessment of this important demographic progression. It is argued that fertility decline in Mauritius has been hindered by cultural composition, assisted only modestly by ongoing development, but aided significantly by family planning program intervention and by a remarkable wide recognition at government and individual levels of the diseconomies associated with population growth in a congested society; comparisons are made with other densely peopled, small islands. Spatial variations in fertility and in family planning activity are slight, but Western economic theories of fertility are found to be helpful in interpreting significant temporal fluctuations.

Africa↗
PubMed1989

Development of an ELISA to detect early local relapse of colorectal cancer.

The Y haptenic blood group determinant is expressed on the cells of malignant gastrointestinal tumours and on the normal gastrointestinal epithelium of individuals who can secrete blood group antigens. an enzyme-linked immunosorbent assay incorporating the high affinity biotin-avidin interaction was developed to measure the serum levels of antigens bearing the Y hapten in patients with colorectal cancer. The specificity of the assays was between 88 and 93% and the sensitivity in detecting extensive disease was between 24 and 34%. However, up to 67% of patients with local or abdominal recurrent disease secreted antigens expressing the Y hapten, whereas only 30% of patients with overt hepatic metastases secreted a similar antigen. Recognition of antigens bearing the Y hapten may therefore be useful in detecting early local relapse of colorectal cancer when a second operation to excise the recurrence may be possible.

Antibodies, Monoclonal↗
PubMed1989

A low-protein diet restricts albumin synthesis in nephrotic rats.

High-protein diets increase albumin synthesis in rats with Heymann nephritis but albuminuria increases also, causing serum albumin concentration to be suppressed further than in nephrotic animals eating a low-protein diet. Experiments were designed to determine whether dietary protein augmentation directly stimulates albumin synthesis, or whether instead increased albumin synthesis is triggered by the decrease in serum albumin concentration. Evidence is presented that dietary protein augmentation directly stimulates albumin synthesis, accompanied by a proportional increase in steady-state hepatic albumin mRNA concentration (AlbmRNA) and by an increase in AlbmRNA transcription. When the increased albuminuria resulting from dietary protein augmentation is blunted with enalapril, serum albumin concentration is shown to increase in nephrotic rats. Both albumin synthesis and AlbmRNA increase in these animals despite the greater serum albumin concentration. Albumin synthesis correlates inversely with both serum albumin and serum oncotic pressure in nephrotic rats fed 40% protein, but does not correlate with serum albumin concentration in nephrotic rats fed 8.5% protein (LP), even when serum albumin concentration is reduced. Albumin masses are preserved in LP primarily because of reduced albuminuria. Reduced serum oncotic pressure and dietary protein augmentation combine to stimulate albumin synthesis in nephrotic rats at the level of gene transcription.

Albumins↗
PubMed1989

High protein diets stimulate albumin synthesis at the site of albumin mRNA transcription.

High dietary protein intake directly stimulates albumin synthesis ald albuminuria in rats with Heymann nephritis. Increased albumin synthetic rate might be due to the presence of increased amino acids available for protein synthesis causing more efficient translation of preformed albumin mRNA, or instead might be linked to increased steady state albumin mRNA levels in the liver. Albumin synthesis, hepatic albumin mRNA content, and albumin mRNA relative to beta actin mRNA (as an internal control) (Alb/beta Act), were measured in rats with Heymann nephritis fed either 8.5% protein (LP), or after protein intake was increased to 40% for 4 days (HP). enalapril (E) was used to modulate the proteinuric effect of HP, yielding four experimental groups, LPN (8.5% protein nephrotic, no enalapril), LPE (8.5% protein, enalapril treated), HPN (40% protein nephrotic, no enalapril), and HPE (40% protein, enalapril treated). Dietary protein augmentation increased the rate of albumin synthesis, steady-state albumin mRNA levels, and Alb/beta Act in both HPN and HPE, compared to either LPH or LPE, even though serum albumin concentration was greater in HPE than in either of the groups fed LP. Both albumin mRNA and Alb/beta Act correlated with the rate of albumin synthesis (r = 0.531, P less than 0.05; and 0.553, P less than 0.01 respectively). Nuclear run-on assays were performed using nuclei isolated from the livers of LPN or HPN to determine whether increased albumin mRNA resulted from an increase in the rate of albumin mRNA transcription.(ABSTRACT TRUNCATED AT 250 WORDS)

Albumins↗
PubMed1988

Going back to basics.

Explore the source record for details and available documents.

Centralized Hospital Services↗
PubMed1988

Beta-human chorionic gonadotropin as a monitor of pregnancy outcome in in vitro fertilization-embryo transfer patients.

Serum human chorionic gonadotropin (hCG) was studied to test its predictability of pregnancy outcome in in vitro fertilization (IVF) patients. The mean +/- standard deviation of serum hCG concentration related to the day complete clearance of exogenous hCG was derived from 47 single term pregnancies as a normal range. This range can be used to predict spontaneous abortion (77%), multiple pregnancy (60%), and abortion in multiple-sac pregnancies terminating in the birth of fewer infants than the initial number of sacs (80%). The results also showed that our stimulation protocol did not affect the clearance rate and doubling time of endogenous hCG or implantation time as suggested by the time of endogenous hCG detection and that spontaneous abortion may be due to late implantation.

Chorionic Gonadotropin↗
PubMed1988

Snowmobile injuries in northern Newfoundland and Labrador: an 18-year review.

The charts of 310 consecutive patients with snowmobile injuries admitted to Charles S. Curtis Memorial Hospital, St. Anthony, Newfoundland, during the years 1969 through 1986 were reviewed in order to determine the causes and possible ways of prevention of these injuries. There were 237 males and 73 females. Most patients were less than 30 years of age (73%). Drivers represented 57% of the injured. Falling off the machine and collisions were responsible for 60% of the injuries; 3.0% were due to mechanical failure of the snowmobile. The lower limbs and head and neck regions were most commonly affected (42.6 and 27.6%, respectively); less than 10% of the patients were wearing helmets at the time of the accident. We conclude that the human factor was responsible for the majority of the injuries. We recommend enforcement of legislation, intensification of public education about the hazards of driving snowmobiles, and modifications in the design of the engine, especially to provide increased protection for the lower limbs.

Accident Prevention↗
PubMed1987

Large scale transfection of mouse L-cells by electropermeabilization.

Mouse L-cells were transfected by electropermeabilization using the selectable plasmid pSV2-neo which confers resistance to G-418 (Geneticin). The DNA concentration used was 1 microgram/ml, the field strength was 10 kV/cm, the duration of the pulse was 5 microseconds. Transfection yield was optimal at a temperature of 4 degrees C when using a time in between consecutive pulses of 1 minute compared to shorter (of the order of seconds) or longer (3 minutes) time intervals. A more detailed study of the relationship between the number of pulses applied (up to 10) and transfection yield showed it to be almost linear in this range at 4 degrees C. The yield of transfectants in response to 10 pulses was up to 1000 per 10(6) cells (using 3.3 pg DNA per cell). The influence of the growth phase of the cells on the transfection yield and/or the subpopulation of the mouse L-cell line used was shown. Furthermore the clone yield depended on the DNA per cell ratio within a very small range.

Animals↗