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B J Anderson

Publications and source records attributed to B J Anderson.

At least 127 records · Page 7Linked to original sources
PubMed1987

Protection of sheep against footrot with a recombinant DNA-based fimbrial vaccine.

Recombinant Pseudomonas aeruginosa cells containing the Bacteroides nodosus fimbrial subunit gene under the transcriptional control of a strong promoter produce large amounts of B. nodosus-type fimbriae. We have carried out vaccination trials which show that these fimbriae are just as effective as either natural fimbriae or whole cell preparations of B. nodosus in inducing protective immunity against homologous footrot challenge. The recombinant-produced fimbriae are also effective therapeutically in accelerating the rate of healing of pre-existing footrot lesions. These results confirm that the structural subunit of the fimbrial strand is a primary protective antigen against footrot, and demonstrate the practicality and potential of recombinant DNA approaches to the development of new vaccines against B. nodosus and other Type 4 fimbriate pathogens.

Animals↗
PubMed1987

A randomized clinical trial comparing ranitidine and antacids in critically ill patients.

In a randomized trial of gastric pH control for stress ulcer prophylaxis, 200 mg/day ranitidine iv was compared to antacids in 86 patients admitted to an ICU. Six (15%) patients receiving ranitidine and six (13%) given antacids failed to maintain greater than 50% of the hourly gastric pH measurements at or above 4. Increasing the ranitidine dosage to 300 mg/day did not provide additional control. One patient in the antacid group developed an overt upper GI bleed secondary to endoscopically proven erosive disease. We conclude that iv ranitidine in a dosage of 200 mg/day is as effective as antacids in reducing gastric acidity and preventing stress ulcer disease in critically ill patients.

Administration, Oral↗
PubMed1987

The metabolic needs of head trauma victims.

Malnutrition increases the morbidity and mortality associated with severe illness, injury, and sepsis. The neuroendocrine changes associated with trauma intensify the body's metabolic demands. The neuroendocrine response to trauma is discussed. Methods to determine calorie needs of head trauma patients are presented, along with a case study.

Adult↗
PubMed1987

Morphogenetic expression of Bacteroides nodosus fimbriae in Pseudomonas aeruginosa.

Type 4 fimbriae are found in a range of pathogenic bacteria, including Bacteroides nodosus, Moraxella bovis, Neisseria gonorrhoeae, and Pseudomonas aeruginosa. The structural subunits of these fimbriae all contain a highly conserved hydrophobic amino-terminal sequence preceding a variable hydrophilic carboxy-terminal region. We show here that recombinant P. aeruginosa cells containing the B. nodosus fimbrial subunit gene under the control of a strong promoter (pL, from bacteriophage lambda) produced large amounts of fimbriae that were structurally and antigenically indistinguishable from those produced by B. nodosus. This was demonstrated by fimbrial isolation and purification, electrophoretic and Western transfer analyses, and immunogold labeling and electron microscopy. These results suggest that type 4 fimbriated bacteria use a common mechanism for fimbrial assembly and that the structural subunits are interchangeable, thereby providing a basis for the development of multivalent vaccines.

Amino Acid Sequence↗
PubMed1987

Western blot (immunoblot) analysis of the fimbrial antigens of Bacteroides nodosus.

The roles of the fimbrial subunit and the putative basal protein antigens in the serological classification of Bacteroides nodosus have been examined by Western blot (immunoblot)-antibody binding studies of fimbriae isolated from a wide range of strains representative of different serogroups and serotypes. Fimbrial subunits were recognized by antiserum against the homologous serogroup but not generally by heterologous antisera, whereas recognition of the basal antigen was independent of serological classification. Secondary cross-reaction patterns among fimbrial subunits indicated that some serogroups may be more closely related than others. Examples include serogroups C and G and serogroups D and H. Similar analyses of isolates classified within serotypes A1 and A2, with serotype-specific antisera, showed that this subdivision is also determined by the fimbrial subunit and that significant variation does occur even at this level. These studies suggest that the various serogroups and serotypes of B. nodosus comprise a series of overlapping sets of antigenically related strains.

Antigens, Bacterial↗
PubMed1986

Massive hemoptysis.

Hemoptysis is usually a symptom of cardiopulmonary disease and is generally not in itself associated with death. A blood loss into the tracheobronchial tree of 600 ml in 24 hours or at a rate that poses a threat to life is referred to as massive hemoptysis. Hypervascularity within the bronchial circulation, usually associated with diffuse inflammatory disease of the lung, is common in patients with massive hemoptysis. Management should be directed at maintenance of oxygenation and localization of the source of bleeding. Temporizing maneuvers such as iced saline lavage, intravenous administration of vasopressin, endobronchial tamponade and bronchial artery embolization will often stabilize the patient in preparation for definitive surgery. Such a sequential plan of management may result in a 50% reduction in the rate of death from massive hemoptysis, which is otherwise 50% to 100%.

Bronchoscopy↗
PubMed1986

Pacemaker follow-up: its role in the detection and correction of pacemaker system malfunction.

The goal of pacemaker follow-up is not only to detect battery depletion but also to detect all malfunctions of the pacing system and, when possible, to correct such problems using programming. During one year, we discovered 61 such malfunctions in a clinic of 1065 patients (5.7%). These were more frequent in the first year (7.7%) than in the third to fifth years of follow-up (range 3.1-4.8%). The incidence rose again in the sixth and subsequent years (7-7.7%). Despite a significant occurrence of malfunctions (5.2%) among multiprogrammable pacemakers, the necessity for operative intervention for their correction was low (1.2%). Sensing problems were the most common (57%) and the most likely to be corrected by reprogramming (85%); problems involving loss of capture were less likely to be corrected by programming (38.5%). Battery depletion accounted for only 18% of malfunctions, occurring earliest in the forty-third month of follow-up. Pulse generator longevity of those devices reaching end of battery life during the study period was 68.6 +/- 16.7 months (mean + SD). We conclude that specialized pacemaker follow-up continues to be necessary despite improved pulse generator reliability and longevity. Indeed, with reprogramming, it presently plays an even more important role than in the past. Follow-up should be oriented not only to the detection of battery depletion but also toward a comprehensive surveillance of pacemaker system function.

Equipment Failure↗
PubMed1986

Variation in the structural subunit and basal protein antigens of Bacteroides nodosus fimbriae.

The fimbriae of Bacteroides nodosus play a major role in protective immunity against ovine footrot and are an important determinant in the serological classification system that divides field isolates into at least eight serogroups and 16 serotypes. Purified fimbriae contain two polypeptide antigens, the structural subunit of the fimbrial strand (molecular weight about 17,000) and a basal protein (molecular weight about 80,000), both of which exhibit structural variation. Fimbriae were prepared from all prototype strains, as well as from a number of other isolates representative of each of the B. nodosus serotypes, and analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Substantial variation was observed in the electrophoretic mobility of the fimbrial subunits from the prototypes of each of the eight serogroups. With the exception of serogroup H, which is an unusual case, the apparent molecular weights of the fimbrial subunits ranged from about 16,500 in serogroup D to 19,000 in serogroup F (serotype 1); in serogroup A, B, C and E, the apparent molecular weights were clustered in the range of 17,000 to 17,500, whereas serogroup G was about 18,500. Serogroup H fimbriae appeared to consist of two smaller polypeptides, which in the prototype (H1) had apparent molecular weights of about 6,000 and 10,000 and which seem to have arisen as a consequence of an internal proteolytic nick in the original subunit. Electrophoretic variation in the fimbrial subunit was also observed between different serotypes, although with the exceptions of serogroups F and H, this was not as pronounced as between the serogroups. Examination of a number of isolates classified within the same serotypes showed that some variation, although minor, also occurred at this level. The basal antigen exhibited significant variation at all levels of the serotypic hierarchy in a manner apparently unrelated to the classification system. Among the range of isolates examined, the apparent molecular weight of this antigen varied from about 77,000 to 88,000.

Antigens, Bacterial↗
PubMed1985

Cerebrospinal fluid myelin basic protein as a prognostic marker in patients with head injury.

Despite increasing interest in identifying biochemical and serologic markers to judge the severity of closed head injury in comatose patients, clinical variables remain the most readily available methods for assessing prognosis. In a series of 35 severely head-injured comatose patients, the cerebrospinal fluid (CSF) level of myelin basic protein (MBP) was analyzed by radioimmunoassay. MBP levels during the first week after injury were significantly correlated with the Glasgow outcome score at 7 days (p less than .005), 3 months (p less than .005), and 6 months (p less than .05) postinjury. Measurement of CSF MBP appears to be a useful laboratory adjunct to clinical assessment, for judging the outcome of severely head-injured patients.

Adolescent↗
PubMed1984

A theoretical protocol for nutritional maintenance in head-injured patients.

Multiple trauma increases the nutritional needs of patients. Although head-injury victims present special problems, the modality of enteral nutritional offers specific advantages which avoid the complications of malnutrition. The success of enteral nutritional therapy is dependent on knowledgeable nursing assessment and intervention. Certainly, it is a therapeutic maneuver that should be considered in the care of the head-injured, multi-trauma patient.

Craniocerebral Trauma↗
PubMed1984

Isolation and characterization of Bacteroides nodosus fimbriae: structural subunit and basal protein antigens.

We examined the isolation of fimbriae from Bacteroides nodosus. It was found that the best preparations were obtained from the supernatant of washed cells cultured on solid medium, from which fimbriae could be recovered in high yield and purity by a simple one-step procedure. Analysis of such preparations by sodium dodecyl sulfate gel electrophoresis showed that greater than 98% of the protein consisted of fimbrial structural subunits whose molecular weight was ca. 17,000. These preparations also usually exhibited minor contamination with a polypeptide of ca. 80,000 molecular weight, as well as trace amounts of lipopolysaccharide. Attempts to release additional fimbriae by the traditional means of subjecting the bacterial cells to physical stress, such as shearing or heating, resulted primarily in an increase in the level of contamination, without significant gain in the yield of fimbriae. Removal of the 80,000-dalton component could not be achieved by any of a variety of techniques normally used in fimbriae purification, including isoelectric precipitation, MgCl2 precipitation, and CsCl gradient ultracentrifugation, implying a direct physical association with the fimbrial strand. Electron micrographs of fractions containing this protein show cap-shaped structures attached to the ends of what appeared to be fimbrial stubs. These observations suggest that the 80,000-dalton polypeptide may actually constitute the basal attachment site which anchors the fimbria to the outer membrane, analogous to a similar protein recently described in enterotoxigenic strains of Escherichia coli. In B. nodosus, this 80,000-dalton protein is a major surface antigen, and like the fimbrial subunit, exhibited variation in electrophoretic mobility between serotypically different isolates.

Antigens, Bacterial↗
PubMed1984

Cloning and expression in Escherichia coli of the gene encoding the structural subunit of Bacteroides nodosus fimbriae.

Bacteroides nodosus is the primary causative agent of ovine foot rot. Virulent isolates of this bacterium contain fimbriae which appear to play a major role in both infectivity and protective immunity. This paper presents the cloning and expression in Escherichia coli of the gene encoding the structural subunit of the fimbriae of B. nodosus. Total DNA was isolated from B. nodosus VCS 1001 (serogroup A), digested with HindIII, and inserted into the positive-selection vector pTR262. Recombinant E. coli clones were screened directly with anti-fimbrial antiserum by using a colony immunoassay. Several positive colonies were identified, each of which contained the same 5.5-kilobase HindIII insert. The prototype has been designated pBA101. Some clones also contained additional flanking sequences from the B. nodosus genome. Western transfer analyses verified that the positive clones were producing the B. nodosus fimbrial structural subunit, molecular weight ca. 17,500. The level of expression of the antigen in E. coli was comparable to that in B. nodosus itself and was unaffected by the insertion site or orientation of the cloned fragment, indicating that synthesis was being directed from an internal promoter. Restriction mapping and deletion analyses localized the fimbrial subunit gene to the vicinity of a PvuII site near the central region of the original HindIII insert. The expressed antigen was located in the membrane-cell wall fraction and may be exposed on the surface of the recombinant E. coli cells.

Bacterial Proteins↗