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Biomedical subjects

J M Jones

Publications and source records attributed to J M Jones.

At least 181 records · Page 10Linked to original sources
PubMed1987

The successful surgical removal of intracranial nasogastric tubes.

Intracranial penetration during attempted nasogastric intubation is a rare, usually lethal, but avoidable complication. Such incidents are associated with facial and basilar skull fractures, acute neurologic deterioration, and litigation. We report two such incidents and the successful surgical procedure which utilized craniotomies positioned such that the nasogastric tubing could be removed in small, straight segments. The tubing in each case was removed without increasing the neurologic deficit, and the patients made an acceptable recovery considering their premorbid status.

Adolescent↗
PubMed1987

Generation of Tn5 insertions in streptococcal conjugative transposon Tn916.

A method has been developed for the introduction of Tn5 into Escherichia coli plasmid chimeras containing Streptococcus faecalis DNA. Tn5 could be introduced via a lambda::Tn5 delivery vehicle. The system proved to be particularly efficient and facilitated insertions at numerous sites on DNA containing the 16-kilobase conjugative transposon Tn916. It was possible to introduce some of the resulting Tn916::Tn5 derivatives back into S. faecalis by using a recently developed protoplast transformation procedure. A presumed zygotic induction resulted in insertion of the Tn916 derivatives at multiple sites in the S. faecalis chromosome.

Bacteriophage lambda↗
PubMed1987

Transfer of the conjugal tetracycline resistance transposon Tn916 from Streptococcus faecalis to Staphylococcus aureus and identification of some insertion sites in the staphylococcal chromosome.

The Streptococcus faecalis pheromone-dependent conjugative plasmid pAD1::Tn916 and the membrane filter-dependent conjugative plasmid pPD5::Tn916 were used to introduce Tn916 into Staphylococcus aureus by intergeneric protoplast fusions and intergeneric membrane-filter matings. In recombinants obtained by protoplast fusion where no plasmid DNA could be detected, tetracycline resistance resulted from transposition of Tn916 from pAD1 to the S. aureus chromosome. Transformation analyses showed that S. aureus Tn916 chromosomal insertions occurred near pig, ilv, uraA, tyrB, fus, ala, and the trp operon. DNA hybridization analyses of EcoRI- and HindIII-digested chromosomal DNAs confirmed the diversity of chromosomal sites involved and demonstrated that the inserts were Tn916 insertions rather than integrations of all or part of pAD1::Tn916. Both pAD1::Tn916 and pPD5::Tn916 were transferred to S. aureus by membrane-filter matings. These plasmids remained intact and expressed tetracycline resistance in S. aureus. S. aureus strains carrying pAD1::Tn916, but not a chromosomal insert of Tn916, and any one of several conjugal gentamicin-resistance plasmids lost their ability to serve as conjugal donors of the gentamicin-resistance plasmids.

Chromosome Mapping↗
PubMed1987

Diagnosis of pulmonary hemorrhage in the immunocompromised host.

The efficacy of bronchoalveolar lavage (BAL) in diagnosing pulmonary hemorrhage was studied in 51 immunosuppressed patients with new pulmonary infiltrates. Similar studies were performed in a control group of 8 nonimmunocompromised patients. Hemosiderin content in Prussian-blue-stained alveolar macrophages obtained by BAL was graded using a numerical scale. This "hemosiderin score" correlated closely with the degree of hemorrhage seen in corresponding histologic sections in the 26 patients from whom a lung biopsy or autopsy specimen was available. Severe pulmonary hemorrhage was ultimately diagnosed in 14 cases, and a mild degree of hemorrhage was found in an additional 19 cases. Thrombocytopenia and invasive fungal infections were statistically associated with severe hemorrhage, as was an increased percentage of alveolar macrophages in the BAL sample. This study demonstrates the efficacy of BAL in diagnosing occult pulmonary hemorrhage in the immunosuppressed host and highlights risk factors associated with hemorrhage in this setting.

Acquired Immunodeficiency Syndrome↗
PubMed1987

The value of early mobilisation in the treatment of Colles' fractures.

Unilateral Colles' fractures in 187 patients over the age of 55 years were studied in a randomised prospective trial: 97 fractures were minimally displaced and were treated either conventionally or in a crêpe bandage; 90 displaced Colles' fractures were reduced and of these 47 were treated conventionally while 43 were encouraged to mobilise the wrist in a cast which restricted extension. Early wrist movement hastened functional recovery and led to earlier resolution of wrist swelling. Discomfort was no greater than in patients who were treated conventionally. The bony deformity, which recurred irrespective of the method of treatment, was not adversely affected by early mobilisation.

Aged↗
PubMed1987

Storage of sperm in the reptilian oviduct.

Female reptiles have the ability to store sperm within their reproductive tracts for extended periods of time. Sites of sperm storage in lizards and snakes include both the anterior vagina and the infundibulum. Vaginal receptacles are found in between longitudinal folds (snakes) and in tubules formed by invaginations of the epithelium (lizards). Infundibular receptacles are alveolar or tubular in structure and are formed from invaginations into the lamina propria of the oviduct wall. In turtles, sperm are stored in the posterior portion of the tuba, in tubular albumen-secreting glands. Sperm may be embedded within the cells of the receptacles, but the membranes of each remain intact. The morphology of the receptacles is characteristic of the normal glands of the area.

Animals↗
PubMed1986

Strain and sex differences in susceptibility of rats to dioctyltin dichloride.

Treatment with dioctyltin dichloride (DOTC) induced increased mortality, atrophy of the thymus and suppression of responses to concanavalin A. Brown Norway (BN) rats were more susceptible than Lewis (LEW) to the lethal effects of DOTC and males were more susceptible than females. Increased mortality did not correlate with changes in the histological appearance of the thymus. LEW X BN F1 hybrids resembled the LEW parent in susceptibility to the lethal effects of DOTC and the BN parent in susceptibility to changes in the thymus.

Animals↗
PubMed1986

Inherited variations in glomerular handling of antigen between Lewis and DA rats.

Inherited differences in the quantity and site of renal deposition of antigen were studied in two inbred strains of healthy rats, one of which, Lewis, is susceptible to Heymann's nephritis and the other (DA) is resistant. Deposition of human cationic immunoglobulin G (IgG) was significantly less in the liver, spleen and kidneys of Lewis rats compared with DA rats, which suggests that the density of the negatively charged molecules in the capillary walls of Lewis rats is less than in DA rats. Immunofluorescent studies of the kidneys 15 min after administration of cationic IgG showed that it could be detected only on the glomerular basement membrane (GBM) and that the intensity of the deposits was less in Lewis rats. The mesangial uptake of aggregated IgG was greater in DA rats at all times studied. There was remarkable similarity in the glomerular processing of cationic IgG and aggregated IgG in both strains. These differences in glomerular properties, capillary charge and mesangial uptake may lead to differences in the deposition of antigen within the glomerulus and in the response to the subsequent inflammatory reactions. This provides a new hypothesis for genetic predisposition of individuals to particular glomerulopathies.

Animals↗
PubMed1986

The role of bronchoalveolar lavage in the diagnosis of invasive pulmonary aspergillosis.

Cultures and histochemical stains for fungi were performed on concentrated, cytocentrifuged bronchoalveolar lavage (BAL) samples from 82 immunocompromised patients undergoing bronchoscopic evaluation of new pulmonary infiltrates. Aspergillus hyphae were identified in 9 of 17 BAL samples from patients with invasive pulmonary aspergillosis and from 3 of the remaining 65 study patients without this diagnosis. Thus, the presence of Aspergillus hyphae in BAL samples had a 53% sensitivity, 97% specificity, and 75% positive predictive value for the diagnosis of invasive pulmonary aspergillosis. BAL fungal cultures were positive in only 4 of 17 cases (23% sensitivity). A combination of fungal stains and cultures yielded a diagnostic sensitivity of 58% and a specificity of 92%. Results of routine fiberoptic bronchoscopy procedures in the 17 patients with aspergillosis who had BAL and in a retrospectively identified group of 10 patients with invasive aspergillosis who had only routine bronchoscopy were tabulated. Routine bronchoscopy procedures yielded a diagnosis in 5 of 27 cases (22% overall yield), with washings diagnostic in 4 of 27 cases (15%), and transbronchial biopsies positive histologically in 2 of 11 cases (18%). BAL is a valuable first procedure for diagnosing invasive pulmonary aspergillosis in the compromised host.

Adult↗
PubMed1986

Latex agglutination tests for detection of Candida antigens in sera of patients with invasive candidiasis.

The utility of two latex agglutination tests in detecting antigenemia in patients with invasive candidiasis was studied. To perform one test, we treated sera with protease and heat to free mannan from antibodies to mannan. Latex beads coated with antibodies to mannan detected mannan in supernatants. In the second test, untreated sera were tested for capacity to agglutinate a commercially available preparation of latex beads coated with antibody to Candida. Two panels of sera were analyzed with the tests. One comprised 355 sera sequentially collected from 75 leukemic patients who underwent 97 episodes of chemotherapy resulting in neutropenia. The other panel comprised 364 sera collected only at the time candidiasis was suspected from 150 patients with a variety of underlying diseases. Of 23 episodes of invasive candidiasis in leukemic patients, antigenemia was detected in 18 (78%) by the mannan latex agglutination test and in 11 (48%) by the commercial test. For the second serum panel the respective tests detected antigenemia in only 22% and 19% of patients with invasive candidiasis. While latex agglutination tests for circulating Candida antigens may be useful for diagnosing invasive candidiasis, the transient nature of antigenemia requires frequent testing of patients' sera and limits the usefulness of the tests in diagnosing invasive candidiasis.

Antigens, Bacterial↗
PubMed1986

Ergotamine tartrate dependency: features and possible mechanisms.

Based on our clinical experience and the data reviewed and presented in this report, we propose that a state of physical dependency to ergotamine tartrate exists. This dependency state is characterized by the irresistible and dependable use of ergotamine tartrate and is contingent upon a self-sustaining, rhythmic headache/medication cycle that reflects the dependency. The headache and accompaniments (withdrawal headache?) represent the primary withdrawal symptoms. The presence of this state appears to render patients refractory to other forms of preventative therapy, which can be effective only when ergotamine is discontinued and the cycle broken. If the condition is left untreated, it is likely though by no means certain that the more traditional aspects of ergotism will evolve, although variable susceptibility and tolerance to ergotamine tartrate have been demonstrated. The mechanism of this disorder remains uncertain but might be related to the influence of ergotamine tartrate on the limbic-hypothalamic-pituitary-adrenal axis and other aminergic centers (locus ceruleus), areas considered by some as the central loci for the pathogenesis and associated symptoms of migraine.

Adult↗
PubMed1986

Arbovirus infection in a Murray Valley community.

Serum antibodies to Ross River virus and Murray Valley encephalitis virus were measured during 1974-1975 in residents of Echuca, an urban Murray Valley community. A representative group of volunteers was obtained by random selection of households. The prevalence of antibodies to both viruses increased progressively with age. Prevalence was equal in both sexes for both viruses in all age groups, indicating that the risk of infection was mainly determined by geography rather than by personal activities. Antibody levels remained unchanged in the following year when there was no disease activity in the area. The stability of antibody levels permitted retrospective estimates of mean rates of infection. These were approximately 0.4% per annum for both viruses when age was used as the index for years of exposure. With allowance for other factors, the best estimate for both virus infections is probably closer to 1%. The morbidity rate for Ross River virus infection appeared to be low. It is concluded that infection with Ross River virus and with Murray Valley encephalitis-related viruses is endemic in the Murray Valley.

Adolescent↗
PubMed1986

Analysis of cell wall extracts of Candida albicans by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blot techniques.

Cell walls of intact yeast- and mycelial-phase Candida albicans B311 were extracted with different compounds: dithiothreitol, dithiothreitol with protease, dithiothreitol with lyticase, and dithiothreitol with protease followed by beta-glucuronidase with chitinase. Extracts were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blot techniques. Dithiothreitol extracts contained the most satisfactory array of components for study. Analysis of these extracts demonstrated that the outer cell wall layers of Candida blastoconidia and germ tubes contained a complex array of polysaccharides, glycoproteins, and proteins. The proteins contributed to a latticework stabilized by covalent bonds that was important in determining the porosity of the outer cell wall layers. When equivalent weights were analyzed, mycelial-phase extract contained a more varied array of proteins than did yeast-phase extract. Only a portion of proteins in mycelial-phase extract elicited antibody responses in hyperimmunized rabbits or infected humans. A polysaccharide-rich, high-molecular-weight component (migrating at a position that would correspond to proteins having molecular weights of 235,000 to 250,000) and a protein component (molecular weight, 19,000) were readily demonstrable in the mycelial-phase extract but could not be identified in the yeast-phase extract.

Animals↗
PubMed1986

Identification of two germ-tube-specific cell wall antigens of Candida albicans.

Outer cell wall layers of intact yeast- and mycelial-phase Candida albicans B311 were extracted with dithiothreitol. Antisera against mycelial-phase organisms were absorbed with yeast-phase organisms or yeast-phase extract and used to stain Western blots of sodium dodecyl sulfate-polyacrylamide gels loaded with yeast- and mycelial-phase extracts. Autoradiography of gels loaded with extracts from organisms surface labeled with 125I was used to detect surface antigens containing proteins. Antigen bands of interest identified in Western blots were cut from the blots and used to immunize rabbits. Two antigens were identified in the mycelial-phase extract which were not present in the yeast-phase extract. The first was a 19-kilodalton protein that was present in the cell walls of germ tubes but was not expressed on their surfaces. The second was a polysaccharide-rich high-molecular-weight antigen which was expressed on the surface of the germ tube. Treatment of mycelial-phase extract with protease and endo-beta-N-acetylglucosaminidase H demonstrated that this antigen was composed of polysaccharides linked through di-N-acetylchitobiose groups to proteins.

Antigens, Fungal↗
PubMed1986

The use of ketoconazole in the treatment of blastomycosis.

We retrospectively reviewed our experience using ketoconazole in the therapy of blastomycosis. Over the course of 30 months, blastomycosis was diagnosed in 11 patients. Their clinical presentations ranged from the asymptomatic pulmonary nodule to the adult respiratory distress syndrome. Six of 8 patients treated with ketoconazole completed a 6-month course of 400 mg daily. Seventeen to 40 months after completion of therapy, the patients who had completed 6 months of therapy were well. Ketoconazole should play a major role in the therapy of blastomycosis because of its efficacy and because its administrative costs are lower than those of amphotericin B. It can be recommended for patients who have been symptomatic for longer than 3 wk and are not improving and for those who undergo resection of an asymptomatic pulmonary nodule. Amphotericin B remains the drug of choice in patients with life-threatening illness who require ventilatory assistance, have developed renal failure, or have central nervous system involvement. Severely immunocompromised patients with disseminated disease should also be treated with amphotericin B. Patients treated with ketoconazole should have close medical follow-up.

Adult↗
PubMed1986

Persistent infection as a cause of renal disease in patients submitted to renal biopsy: a report from the Glomerulonephritis Registry of the United Kingdom MRC.

We report the results of a survey within the United Kingdom of the importance of persistent systemic infection in patients with unexplained renal disease who undergo renal biopsy. Twenty-two units participated. Overall 1.7 per cent of patients undergoing biopsy had an infection but there was large variation between units. Interstitial nephritis and amyloid deposits were more common in patients with infection, and minimal change nephropathy was less common than in patients undergoing biopsy but without infection. The respiratory tract was the most common site of infection but was rarely associated with glomerulonephritis of which the most common cause was infective endocarditis. Drug treatment may have caused the renal lesion in 16 per cent of patients. Amyloid deposits, present in 13.6 per cent of patients, was the most common cause of progressive renal failure. Most other patients had some improvement in renal function once the putative cause, whether infection or antibiotic, was removed.

Adolescent↗