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Biomedical subjects

C J Harrison

Publications and source records attributed to C J Harrison.

At least 145 records · Page 8Linked to original sources
PubMed1988

Herpes simplex virus glycoprotein treatment of recurrent genital herpes reduces cervicovaginal virus shedding in guinea pigs.

Treatment of previously infected guinea pigs with herpes simplex virus (HSV) glycoproteins reduces the frequency and severity of subsequent genital recurrences. An effective vaccine should also reduce episodes of viral shedding. In this study, HSV glycoproteins B and D treatment of animals experiencing recurrent genital herpes reduced the frequency of both clinical recurrences and cervicovaginal viral shedding. When virus was shed, however, the peak viral titer and duration of shedding was unaltered.

Animals↗
PubMed1987

A cell line from Wilms' tumour with deletion in short arm of chromosome II.

A cell line (T3/73) from a Wilms' tumour has been established from a 9 month-old boy with aniridia. The tumour was removed in 1973. On histological examination a diagnosis of Wilms' tumour was made which showed undifferentiated areas, marked tubule formation and abundant striped muscle fibres. The tumour cells, which are fusiform, grew rapidly in culture without the addition of growth factors, and have undergone over 100 passages. Approximately 95% and 5% were positive for desmin and cytokeratin, respectively. The cell doubling time was 28 hr. Cytogenetic studies revealed a karyotype of 46,XY,del(11) (p12::p14). Although the cells stained very intensely with a monoclonal antibody that detects oncogene ras p 21 antigen, Southern blot analysis using c-Ha-ras as a probe failed to reveal an obvious deletion or amplification of either Ha-ras allele.

Antibodies, Monoclonal↗
PubMed1987

Antibody response to herpes simplex virus glycoprotein D: effects of acyclovir and relation to recurrence.

We developed an enzyme-linked immunosorbent assay (ELISA) for measuring the antibody response to herpes simplex virus (HSV) glycoprotein D (gD). The ELISA was specific and more sensitive than immunoblotting techniques. Antibody to HSV gD was detected in 10 of 12 sera (geometric mean titer, 36.3) obtained from HSV-2-infected guinea pigs 14 days after intravaginal inoculation, and the titer increased to greater than or equal to 5,120 on day 60. Therapy with acyclovir delayed and diminished the antibody response to gD, although by day 60 the titers of antibody to gD in acyclovir-treated animals were not significantly different from those in controls. An increased titer of antibody to gD seemed to be associated with a reduced number of recurrent episodes and to a reduced number of days with recurrent lesions.

Acyclovir↗
PubMed1987

Relation of the outcome of conjunctivitis and the conjunctivitis-otitis syndrome to identifiable risk factors and oral antimicrobial therapy.

The epidemiology, microbiology and clinical outcome of the conjunctivitis-otitis syndrome (CJ-AOM) was investigated in a rural private practice concurrent to a double blind placebo-controlled study of orally administered amoxicillin for prevention of acute otitis media (AOM) secondary to conjunctivitis. Bacterial pathogens were isolated when greater than 15 polymorphonuclear leukocytes/high power field were observed on Gram-stained smear of conjunctival secretions. Nontypable Haemophilus influenzae biotype 2 predominated in CJ-AOM; however, Streptococcus pneumoniae was isolated nearly as frequently as H. influenzae in conjunctivitis without AOM. Younger age (P = 0.001) and more episodes of AOM in the previous year (P = 0.006) were risk factors for CJ-AOM. Persistence of AOM was frequently observed in CJ-AOM. The frequency of AOM secondary to conjunctivitis was reduced (P = .01) in amoxicillin recipients (2 of 41) compared with placebo (11 of 42), but amoxicillin failed to eradicate nasopharyngeal carriage of H. influenzae. More episodes of AOM per year (P less than 0.001) and day care (P less than 0.001) were found to be risk factors for AOM secondary to conjunctivitis.

Acute Disease↗
PubMed1987

A scanning electron microscopy study of double minutes from a human tumour cell line.

Double minutes from a human tumour cell line were examined in intact metaphase spreads using scanning electron microscopy. They were discrete, acentromeric, compact spheres of chromatin fibres similar to the chromatin of the metaphase chromosomes within the same cells. They were closely associated with the telomeres and chromatids of the metaphase chromosomes.

Cell Line↗
PubMed1986

Buccal cellulitis reevaluated.

We studied 72 children (17 prospectively) with acute buccal cellulitis. The median age was 11 months. Fifty-five percent of patients were bacteremic, and three children without meningeal signs or symptoms had concomitant meningitis. Cellulitis aspirate cultures (eight of 35 positive) and urine bacterial antigen tests (13 of 27 positive) were useful in making an etiologic diagnosis. Infections due to other bacteria were clinically indistinguishable from those due to Haemophilus influenzae type b. The right cheek was affected more often than the left, and only 23 (32%) of 72 patients had otitis media ipsilateral to the involved cheek. The pathogenesis of buccal cellulitis likely involves direct mucous membrane invasion rather than spread from the ipsilateral middle ear.

Acute Disease↗
PubMed1986

A structural basis for R- and T-banding: a scanning electron microscopy study.

The structure of reverse (R)-banded and telomeric (T)-banded chromosomes was studied by examination of the same chromosomes first in the light microscope (LM) followed by the scanning electron microscope (SEM). This procedure demonstrated a structural basis to both the R- and T-banding techniques. A direct correlation was shown between the LM staining patterns and the structural patterns observed in the SEM. In the R-banded chromosomes the positively stained R-bands, viewed by LM, corresponded to highly fibrous three-dimensional regions in the SEM. The negatively stained R-interbands corresponded to flatter regions from which material appeared to have been extracted. These structural observations strongly support the suggestion that chromosomal material is preferentially lost from the R-interbands with aggregation of fibres in the R-bands. T-banded chromosomes showed a similar structure to the R-banded chromosomes. The positively stained T-bands located at the telomeres corresponded to regions of highly aggregated fibres. The remainder of the chromosome, corresponding to the negatively stained area, had a flattened and extracted appearance. These similarities in morphology between the T- and R-banded chromosomes support the view that T-bands result from a progressive breakdown of the R-banded chromosome structure.

Azure Stains↗
PubMed1986

Cefuroxime versus ampicillin plus chloramphenicol in childhood bacterial meningitis: a multicenter randomized controlled trial.

In a multicenter randomized trial, 107 children with bacterial meningitis were initially given either cefuroxime or ampicillin plus chloramphenicol. Patients were alternately assigned to 7- or 10-day courses of the designated antimicrobial regimen. CSF isolates included Haemophilus influenzae type b (89, of which 25% were beta-lactamase positive), Streptococcus pneumoniae, and Neisseria meningitidis. Although mean CSF bactericidal titers against Haemophilus isolates were 1:6 in each treatment group, H. influenzae was cultured from CSF in four of 39 patients receiving cefuroxime, 24 to 48 hours after initiation of therapy, compared with none of 40 patients given ampicillin plus chloramphenicol (P = 0.11). Clinical cure rates were similar (95%); one death occurred in each group. One child given cefuroxime had persistent meningitis after 5 days of therapy, and mastoiditis with secondary bacteremia developed in one on day 10. Three patients had relapse or reinfection. One patient who received cefuroxime for 10 days had a relapse of epiglottitis 17 days later, and of the patients given ampicillin plus chloramphenicol, one had a relapse of meningitis 1 week after 7 days of therapy, and bacteremia developed in one 42 days after completion of 10 days of therapy. No increase in either in-hospital complications or relapses occurred with a 7-day treatment course. Proof of the equivalence of the antibiotic regimens and the efficacy of 7-day courses of treatment, as well as the consequences of delayed CSF sterilization, will require additional investigation.

Adolescent↗
PubMed1986

Antibody response, recurrence patterns and subsequent herpes simplex virus type 2 (HSV-2) re-infection following initial HSV-2 infection of guinea-pigs: effects of acyclovir.

The production of antibody to specific herpes simplex virus type 2 (HSV-2) polypeptides, the recurrence patterns and the susceptibility to re-infection were studied in the guinea-pig model of genital HSV-2 infection. Further, we defined the effects of acyclovir (ACV) therapy on these parameters of infection. Treatment with ACV reduced the clinical severity of the initial disease but did not affect vaginal viral shedding. Production of neutralizing antibody as well as antibody to the nucleocapsid protein, and glycoproteins B, D and G were all delayed in ACV recipients. ACV treatment of initial infection did not significantly alter the pattern of subsequent recurrence although by several criteria treated animals tended towards decreased recurrences. Re-inoculation with a second strain of HSV-2 resulted in a local cervicovaginal infection but, except for one ACV-treated animal, neural tissue was protected from re-infection.

Acyclovir↗
PubMed1986

Scanning electron microscopy of human metaphase chromosomes.

Preparative methods for scanning electron microscopy of chromosomes are dependent on the original source of material. Chromosomes extracted from unfixed metaphase cells via isolation buffers tend to show topography and surface morphology which may have been induced by the choice of isolation buffer itself. Furthermore, this type of preparation often precludes any chromosome identification, as many metaphases have been pooled, and also the chromosomes from these preparations are not suitable for the banding techniques regularly used in clinical cytogenetics. Our own approach has been to use the standard cytogenetic approach, starting with methanol-acetic acid fixed, air dried metaphase spreads, allowing both identification of individual chromosomes, and also the facility for various banding procedures such as G and C banding to be performed. Chromosomes are subsequently "reprepared" for SEM, using rehydration, glutaraldehyde fixation, and osmium impregnation using Thiocarbohydrazide (TCH). This method produces chromosomes which can be examined at high resolution, without metallic coating, for their topography, surface morphology and chromatin organisation, and the changes produced by banding techniques which give rise to a structural alterations resulting in differential staining in the light microscope.

Cells, Cultured↗
PubMed1985

The structural basis for C-banding. A scanning electron microscopy study.

The same C-banded human polymorphic chromosomes were observed in the light microscope (LM) and then in the scanning electron microscope (SEM) to investigate the structural changes produced by the C-banding technique. C-banded regions, which stained positively in LM, were highly condensed with tightly packed chromatin fibres, resembling non-banded chromosomes. In striking contrast, adjacent non-C-banded regions were represented by loosely arranged fibres, resembling G-banded chromosomes. The significance of these observations in relation to current theories on the effects of C-banding on chromosome structure is discussed.

Azure Stains↗
PubMed1985

Natural killer cell activity in infants and children excreting cytomegalovirus.

Natural killer cell (NKC) activity against uninfected and cytomegalovirus (CMV)-infected fibroblasts and K562 cells was assessed in 39 infants and children excreting CMV and 89 controls. NKC activity in cord blood specimens, healthy donors up to six months old, and donors older than six months showed significant increases (P less than .02) with age. NKC activities of CMV excreters correlated with acute disease characterized by interstitial pneumonitis (IP) and showed differential responses to the three target cells. CMV excreters younger than six months with IP showed greater mean percentage lysis (MPL; 36.6% +/- 10.5%) of CMV-infected cells than did those without pneumonitis (25.9% +/- 10%) or controls (22.1% +/- 8.0%). Excreters older than six months with IP showed activities comparable to controls; NKC activities of excreters without IP were depressed. Significantly elevated activity against uninfected fibroblasts characterized patients with IP regardless of age (MPL, 30.2% +/- 7.3% vs. 4.2% +/- 2.0% for healthy controls and 6.3% +/- 5.4% for excreters without IP). Increased cytolysis of uninfected fibroblasts was therefore associated with more active disease.

Bacterial Infections↗
PubMed1985

Investigation of human chromosome polymorphisms by scanning electron microscopy.

Human chromosome polymorphisms were investigated by scanning electron microscopy (SEM). Centromeric heterochromatin was of a constricted morphology. The extent of the C banded region was demarcated by a prominent circumferential groove in G banded chromosomes. Circumferential grooves were observed within the heterochromatin of chromosome 9, and the number of grooves present reflected the size of the region. Three dimensional viewing of satellites and short arms of acrocentric chromosomes, from different angles in the SEM, provided the opportunity for accurate assessment of the size of satellites to be made. Also, small morphological variations were defined in the SEM when definition was uncertain in the light microscope (LM).

Centromere↗
PubMed1985

Light and scanning electron microscopy of the same human metaphase chromosomes.

A technique has been developed to examine the same G-banded human metaphase chromosomes, first in the light microscope and then in the scanning electron microscope (SEM). A structural involvement in chromosome banding was confirmed by a positional correlation between the G-positive bands observed in the light microscope and the circumferential grooves between the quaternary coils of the metaphase chromosomes, observed in the SEM. In further support of this the regions between the grooves showed a positional relationship with the G-negative or reverse (R) bands. The examination of slightly extended metaphase chromosomes in the light microscope demonstrated that the G-banding pattern corresponded to that described by the Paris nomenclature for metaphase chromosomes. The arrangement of the circumferential grooves of the same chromosomes, observed in the SEM, was shown to relate to that described by the Paris nomenclature for prometaphase chromosomes. Therefore, using the SEM it is possible to demonstrate the details of prometaphase banding in metaphase chromosomes.

Chromosome Banding↗
PubMed1985

A multicenter comparison of related pharmacologic features of cephalexin and dicloxacillin given for two months to young children with cystic fibrosis.

Twenty-one cystic fibrosis patients under 3 years of age were enrolled in an open multicenter study to assess the feasibility of the study design and to compare selected pharmacologic features of cephalexin or dicloxacillin administered orally for 2 months. Patient tolerance and compliance were significantly less for dicloxacillin (p less than .01 and p less than .001, respectively). Superficial Candida infections were more common in the cephalexin group (p = 0.02), however increased stool frequency and nonspecific diaper rashes were more prevalent in patients receiving dicloxacillin (p less than .05). Staphylococcus aureus was isolated from respiratory secretions after 2 months from two dicloxacillin and no cephalexin patients. Areas under the curve and peak serum concentrations were higher for cephalexin (p less than .05 and p = .02), but antistaphylococcal activity in serum was higher for dicloxacillin (p less than .05) due to a lower mean MIC compared to cephalexin. Deep pharyngeal plus routine throat culture yielded more pathogens than either method alone. Express mail and central processing of respiratory specimens was efficient for most organisms, however there was some loss of Streptococcus pneumoniae and Haemophilus influenzae. Cephalexin was associated with better patient acceptance and compliance despite higher rates of superficial fungal infections as compared to dicloxacillin. Cephalexin, routine bacteriologic throat swabs processed locally or centrally, mail-in urine compliance assessment and a multicenter design are feasible components for a long-term prospective evaluation of antibiotic prophylaxis in patients with cystic fibrosis.

Administration, Oral↗
PubMed1984

Influence of 12-O-tetradecanoylphorbol-13-acetate (TPA) on the susceptibility of K562 to natural cytotoxicity: evidence for clonal variation in differentiation-induced changes of lytic sensitivity.

The effect of 12-O-tetradecanoylphorbol-13-acetate (TPA) on the sensitivity to NK cell-mediated lysis of two cloned populations of K562 which exhibit marked and stable differences in their susceptibility to natural cytotoxicity has been examined. Culture in medium supplemented with TPA concentrations of l ng/ml or more invariably caused a decrease in the susceptibility of the sensitive clone E10/P2, whereas treatment of the relatively resistant clone F9/P2 with TPA under identical conditions caused a significant increase in susceptibility to natural cytotoxicity. In both cases the change in susceptibility occurred within 1 day of culture in TPA and was rapidly reversible following removal of the inducing agent. The changes in resistance to natural cytotoxicity induced by TPA were independent of variations in osmotic fragility and were not attributable to alterations in NK cell binding capacity as determined by cold competition analysis. In contrast to the effect of TPA, exposure of E10/P2 and F9/P2 to interferon (IFN) caused a reduction in sensitivity to natural cytotoxicity of both populations which was associated with a decreased capacity to compete for lysis of labelled target cells. These data suggest that the effects of differentiating agents on target susceptibility to NK cell lysis are variable and that responses to TPA are clonally distributed within cell populations.

Cell Differentiation↗