Search PubMed⌕ Search

Biomedical subjects

D Webb

Publications and source records attributed to D Webb.

At least 127 records · Page 7Linked to original sources
PubMed1983

Inherited deficiency of C8 in a patient with recurrent meningococcal infections: further evidence for a dysfunctional C8 molecule and nonlinkage to the HLA system.

An adult male with recurrent meningococcal infections is reported whose serum lacked functional C8 activity but possessed antigenic C8. The addition of 1500 U of purified C8/ml of serum restored hemolytic activity to normal. Four to five times more C8 was required to restore bactericidal activity than to restore hemolytic activity. Bactericidal activity could also be restored by mixing the patient's serum with a second C8-deficient serum that lacked detectable antigenic or functional C8. The patient's serum contained bactericidal antibody for groups A, B, C, and Y meningococci and specific antibody to group Y capsular polysaccharide. There was two to three times more bactericidal antibody activity in the serum than in a pool of normal sera for the infecting strain. Family studies disclosed a sibling who was HLA identical to the patient but whose serum contained normal amounts of total hemolytic and C8 functional activity.

Adolescent↗
PubMed1983

Similar blood pressure but different outcome in rats with DOC and post-DOC hypertension.

It is uncertain whether increased arterial pressure alone or increased arterial pressure combined with some other factor is responsible for the development of malignant-phase hypertension. Our object was to test this comparing two groups of rats with hypertension of different mechanism but of similar duration and degree. Two experiments were done in hypertensive rats. In the first blood pressure was measured in the tail, in the second by intra-arterial catheter and pressure transducer. In the first, hypertension was produced in 30 male Sprague-Dawley rats by unilateral nephrectomy followed by thrice-weekly injections of deoxycorticosterone (12.5 mg) and substitution of 1% NaCl and 0.2% KCl for their drinking water. After four weeks 28 rats survived and systolic blood pressure had risen to 220 mmHg. The survivors were paired by blood pressure and randomly allocated either to continued DOC and salt or to a regime in which DOC was stopped and tap-water was substituted for the NaCl-KCl solution (post-DOC rats). Blood pressure remained similar in the two groups thereafter, but in every case it was the DOC-salt animal of the pair which died first. Fibrinoid arteriolar lesions of malignant-phase hypertension were significantly commoner in DOC-salt animals and, before death, they had more pronounced features of microangiopathic haemolytic anaemia. The second experiment was the same in design as the first except that two weeks after randomization the similarity of blood pressure was confirmed by measurement of intra-arterial pressure in eight pairs of DOC-salt and post-DOC rats. We conclude that increased arterial pressure is not the only factor influencing development of malignant-phase hypertension.

Animals↗
PubMed1981

Animal model for anaerobic lung abscess.

There are no satisfactory animal models for the study of anaerobic lung abscess. Aspiration of food, gastric mucin, or hydrochloric acid, or any combination of these, along with oropharyngeal bacteria, is commonly believed to cause aspiration pneumonia and lung abscess. In the animal model described, none of the adjuvants was effective in producing anaerobic lung abscesses. Anaerobic bacteria derived from dental scrapings of a healthy adult (Peptococcus morbillorum, Fusobacterium nucleatum, Eubacterium lentum, and Bacteroides fragilis), when inoculated transtracheally without any adjuvants into New Zealand male white rabbits, consistently produced lung abscesses. Neither B fragilis by itself nor a mixture of P. morbillorum, F. nucleatum, and E. lentum without the addition of B. fragilis produced lung abscesses. The bacterial isolates used in this study were stored in prereduced chopped-meat-glucose medium and subcultured several times and were found effective in reproducing anaerobic lung abscesses repeatedly. This animal model is suitable for the study of pathogenesis, diagnosis, and treatment of B. fragilis-associated anaerobic lung abscess.

Aerosols↗
PubMed1980

In vitro susceptibility of anaerobic flora of the female genital tract to ampicillin compared to spectinomycin.

Pelvic inflammatory disease (PID) may be caused by anaerobic bacteria and or gonococcus and therefore the efficacy of two antibiotics, ampicillin (AMP) and spectinomycin (SPM) commonly used in this setting was examined against 370 isolates of anaerobic bacteria. At the highest therapeutically achievable serum levels, AMP (16 micrograms/ml) inhibited 83% of all anaerobes and 70% of Bacterioides fragilis, and SPM (128 micrograms/ml) inhibited 98% of all anaerobes and 95% of B. fragilis strains tested. It therefore appears that both AMP and SPM may have a place in the treatment of PID. In our study, greater percentage of anaerobes were susceptible to SPM than previously reported. We used the 'glove box' technique used for testing the susceptibility of anaerobes.

Ampicillin↗
PubMed1979

In vitro activity of mezlocillin and its related compounds against aerobic and anaerobic bacteria.

A total of 900 clinical isolates of aerobic (462 isolates) and anaerobic (438 isolates) bacteria were tested against mezlocillin in comparison with other penicillins, and the aerobes were also tested against cephalothin, cefoxitin, and cefamandole. Among penicillins, mezlocillin was the most effective against Escherichia coli, Klebsiella pneumoniae, Salmonella species, Pseudomonas aeruginosa, and Bacteroides fragilis. Mezlocillin was more effective than cephalothin against Klebsiella pneumoniae.

Aerobiosis↗
PubMed1979

Clinical and experimental evaluation of cefoxitin therapy.

30 patients were treated with i.v. cefoxitin (4-8 g/day), of which 20 had documented infections which included endocarditis (5), lung abscess (4), empyema (4), liver and subhepatic abscess (3), osteomyelitis (3), and pancreatic abscess (1). 14 patients had infections caused by anaerobic bacteria and 5 had endocarditis due to aerobic organisms. All but 2 patients with osteomyelitis of the mandible were cured. Adverse reactions were noted in 7 patients, mostly due to drug fever and leukocytosis; one had Coombs'-positive hemolytic anemia. The average serum cefoxitin levels were 24, 16, 12, and 4 microgram/ml at 1, 2, 3 and 4 h, respectively, and the average serum/pleural fluid ratio was 1:0.5 +/- 0.25. All anaerobic and aerobic isolates except one strain of Bacteroides fragilis were susceptible to cefoxitin at less than or equal to 32 microgram/ml. The concentration of cefoxitin in the tissues was measured in 8 rabbits; it was 4 +/- 1 microgram/ml in the heart and 2 +/- 0.5 microgram/ml in the femur and mandibular tissue, suggesting that the lack of response in cases of osteomyelitis could be due to inadequate antibiotic concentration in the bone. Our study suggests that cefoxitin can be used in the treatment of anaerobic infections and endocarditis due to susceptible organisms.

Abscess↗
PubMed1979

Skin and soft tissue polymicrobial infections from intravenous abuse of drugs.

Skin and soft tissue infections were studied in 21 seriously ill narcotic addicts who had been admitted to hospital. Subcutaneous abscesses were present in 14 patients; cellulitis was noted in 3, pyomyositis in 2 and necrotizing fasciitis in 2. In four patients there was septicemia. Infections in 14 patients (66.6 percent) were associated with anaerobic bacteria, which were the exclusive isolates in 6 patients. In seven patients (33.3 percent) isolates were exclusively aerobic bacteria and in eight both aerobes and anaerobes were present. The anaerobic isolates were clostridia (six), peptostreptococci (five), bacteroides (five), peptococci (three), and one of each of Veillonella, Propionibacterium, Eubacterium, Fusobacterium and Actinomyces. Staphylococcus aureus, generally thought to be the most common cause of subcutaneous infections in addicts, was found only in four (19 percent) patients. The other aerobic isolates were Klebsiella (five) and Enterobacter (four) species. When clinical features or the Gram stain of pus suggest that anaerobic bacteria may be present, antibiotic therapy should be directed against both aerobic and anaerobic bacteria until culture results are available.

Abscess↗
PubMed1978

Myotonia dystrophica: obstetric complications.

We describe the course and outcome of 23 pregnancies in six women affected by myotonia dystrophica in a large Labrador family. A seventh patient had 14 pregnancies, so that the infertility commonly described in this disorder did not apply to this family. The rate of complications was high, particularly in respect of polyhydramnios, premature onset of labor, cesarean section, postpartum hemorrhage, and neonatal deaths. Polyhydramnios indicated that the fetus was abnormal. Direct observation of an atonic uterus at cesarean section supported other evidence that uterine muscle may be affected. We also report a newborn infant with the congenital form of myotonic dystrophy, a manifestation which has been attributed to the effect of a maternal intrauterine factor upon a fetus carrying the gene.

Female↗
PubMed1978

Myotonia dystrophica: unusual features in a Labrador family.

A large family with myotonia dystrophica has been recognized in an isolated area of Labrador. The complete family tree showed 29 of 108 members to be affected, including an infant with the congenital form of the disease. The propositus presented with epiphora and reduced frequency of blinking, with incomplete closure--features that have not previously been stressed. Ten of the younger affected persons had no lens opacities, although most had systemic muscle signs. Slit-lamp examination was therefore not a valuable method of early detection of the disease in the family. Many of the women affected by myotonia dystrophica had obstetric complications, particularly hydramnios, premature onset of labour, necessity for cesarean section, postpartum hemorrhage and neonatal death. Hydramnios was associated in each instances with perinatal death. The fetus in each case of hydramnios may have had the gene for myotonia dystrophica. Immunoglobulin A concentrations were reduced significantly in 27 affected persons in comparison with 77 unaffected family members. There were no such differences for the other immunoglobulin classes.

Adolescent↗
PubMed1978

Effects of caffeine on DRL performance in the mouse.

Mice were trained to stable and efficient DRL 18 sec performance utilizing a nose-poke as the operant. Caffeine, at doses less than 48 mg/kg, increased both response bursts (IRTs less than 3 sec) and longer IRTs, and shifted the IRT distribution towards shorter, nonreinforced IRTs. Auditory feedback for responses decreased the number of bursts emitted and produced performance more resistant to drug effects. These results are similar to those previously reported for caffeine on DRL in the rat, and for amphetamine on DRL in a variety of species.

Acoustic Stimulation↗
PubMed1978

Ticarcillin disodium in anaerobic infections.

Twenty-five patients were treated with ticarcillin disodium, 18 of whom had anaerobic infections that included pleuropulmonary infections (seven), mandibular osteomyelitis (four), perirectal abscess (two), sepsis, primary site unknown (one), liver abscess (one), pelvic abscess (one), decubitus ulcer (one), and synergistic gangrene (one). Seven had no anaerobic infections. Three had anaerobic septicemia. Culture results included anaerobes: peptococci (ten), peptostreptococci (ten), Bacteroides fragilis (six), Bacteroides not fragilis (ten), eubacteria (three), fusobacteria (two), Clostridium (one), Veillonella (one), and acidaminococcus (one); aerobes: Proteus (three), Klebsiella (two), Escherichia coli (two), and streptococci (two). Six patients with mixed aerobic infections initially received gentamicin sulfate in addition. The serum levels were 110 +/- 20 microgram/ml one hour after intravenous infusion of 5 g of ticarcillin disodium. All anaerobic isolates were susceptible at less than or equal to 100 microgram/ml and 85% by less than or equal to 25 microgram/ml of ticarcillin. Sixteen patients responded well to ticarcillin and two failed to respond. Our study suggests that ticarcillin is useful in the treatment of anaerobic infections.

Anaerobiosis↗