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Biomedical subjects

J D Nelson

Publications and source records attributed to J D Nelson.

At least 109 records · Page 6Linked to original sources
PubMed1984

Conjunctival goblet cell densities in ocular surface disease.

Goblet cell densities were determined in the eyes of normal subjects and in the eyes of patients with various ocular surface diseases using an impression cytological technique. For normal eyes goblet cell densities on the interpalpebral bulbar and inferior palpebral ocular surfaces were 443 (+/- 266 [+/- SD]) and 1,972 (+/- 862) cells millimeter, per square, respectively. All patients in the ocular surface disease groups had decreased goblet cell densities compared with subjects with normal eyes. Compared with normal eyes, eyes with keratoconjunctivitis sicca (KCS) demonstrated a 17% greater goblet cell loss on the interpalpebral bulbar compared with the inferior palpebral ocular surface, while eyes with blepharitis and secondary KCS demonstrated an 8% greater loss on the inferior palpebral surface compared with the interpalpebral bulbar ocular surface. Eyes with cicatricial ocular pemphigoid and Stevens-Johnson syndrome demonstrated greater than 95% goblet cell loss on both the interpalpebral bulbar and inferior palpebral ocular surfaces compared with normal eyes.

Adolescent↗
PubMed1984

Adverse reactions to vancomycin used as prophylaxis for CSF shunt procedures.

From January to May 1982, 37 children undergoing CSF shunt procedures in two different countries were enrolled in a randomized, double-blind, controlled study to receive vancomycin hydrochloride (15 mg/kg/dose) or placebo (saline) one hour before surgery and again six hours later. Twenty patients received vancomycin, and 17 received placebo. In the 35 cases that could be evaluated, shunt-associated infections developed in three (17%) of 18 patients who received vancomycin and in four (23%) of the 17 placebo recipients. All infections were caused by Staphylococcus species susceptible to vancomycin. A histaminelike rash developed in seven (35%) of 20 patients during vancomycin infusion. It recurred with readministration in one patient and was accompanied by hypotension in another patient. The reactions were not related to too rapid infusion of vancomycin. Because of the adverse reactions to vancomycin, the study was discontinued.

Adolescent↗
PubMed1984

CSF shunt infections in pediatrics. A seven-year experience.

The medical records of children who had had CSF shunt procedures were reviewed for the seven-year period from 1975 through 1981. There were 516 procedures performed in 297 patients. Only three were ventriculoatrial shunts; the remainder were ventriculoperitoneal shunts. Fifty-nine infectious episodes (11%) occurred in 50 patients (17%); there were three relapses and six reinfections. The infecting pathogen was staphylococci in 75% of the infections and gram-negative bacilli in 19%, and there were two or more pathogens in 15% of the infections. The onset of the infection was within 15 days of surgery in 53% of the cases. The main symptoms were fever, irritability, and shunt malfunction. Gram's stain of the CSF was positive in 46% of the episodes and blood cultures were positive in 29%. Nineteen percent of patients had wound infection and 7% had peritonitis; in most of these cases there were no neurologic signs or symptoms. Thirteen episodes were managed with antibiotic therapy alone; among these, there were three relapses and two reinfections. Thirty-seven episodes were treated with antibiotics and immediate removal of the shunt; there were no relapses and three reinfections. Nine episodes were managed with antibiotics and delayed removal of the shunt; there was one reinfection. The median duration of antibiotic treatment was 15 days, and the time to defervescence was 24 hours in those with immediate removal of the shunt and six days in those in whom the shunt was not removed.

Anti-Bacterial Agents↗
PubMed1984

Pharmacokinetics and bacteriological efficacies of apalcillin and cefpiramide in experimental pneumococcal meningitis.

Rabbits with experimentally induced pneumococcal meningitis were given single 25-mg/kg doses of apalcillin or cefpiramide. Mean percentages of the drug concentration in cerebrospinal fluid versus that in blood serum were 7.6% with apalcillin and 3.9% with cefpiramide. Bactericidal activity in cerebrospinal fluid resulted in mean reductions of from 4 to 5 log10 CFU/ml, and cerebrospinal fluid cultures became sterile for four of six animals treated with each drug.

Ampicillin↗
PubMed1984

Characterization of rat corneal epithelium maintained in tissue culture.

Using Dispase-treated rat corneas, primary cultures of corneal epithelium have been established which are free of contaminating cell types. Cultures were maintained for periods up to 36 days and were monitored with morphological and electrophysiological methods. Phase and scanning electron microscopy revealed a mosaic of polygonal epithelial cells which migrated over the culture plate. Actively migrating cells at the periphery of the culture presented a complex border of ruffles and filopodia. Surface specializations of the epithelial cells, i.e. microvilli, reflected those seen in vivo. Transmission electron microscopy revealed many cytological features common to the intact cornea: bundles of tonofilaments, desmosomes between adjacent cells and glycocalyx-covered microvilli on all free surfaces. These features developed over time in culture. Membrane potentials of the cultured epithelial cells could be recorded intracellularly. Therefore, it appears that pure cultures of rat corneal epithelium which maintain the morphological characteristics of their in vivo counterparts can be grown for considerable periods of time and that their electrophysiological properties can be monitored. This system offers the possibility of studying, under the controlled conditions of tissue culture, a wide variety of factors which might influence the integrity of the corneal epithelium or alter its susceptibility to disease.

Animals↗
PubMed1984

Corneal ulcer-infiltrate associated with soft contact lens use following penetrating keratoplasty.

A review of 100 patients who underwent penetrating keratoplasty revealed 47 who required therapeutic soft contact lenses in the early postoperative period. Twelve corneal ulcer-infiltrates, 11 of which were culture positive, occurred during soft contact lens wear (23% incidence of this complication in contact lens fitted eyes). The most common offending organism was coagulase-negative staphylococcus. The only statistically significant risk factor for infection if a lens was used was the presence of a persistent epithelial defect (p = 0.03). Factors which could not be statistically correlated with corneal ulcer-infiltrate included keratoconjunctivitis sicca, the type of contact lens, the method of donor cornea preservation, lens hygiene, antibiotic and steroid usage, the presence of blepharitis, preoperative bacterial keratitis, and the history of a previously failed penetrating keratoplasty.

Contact Lenses, Hydrophilic↗
PubMed1983

Randomized trial of cefamandole plus amdinocillin versus cefamandole in serious pediatric infections.

In a randomized, prospective clinical trial cefamandole therapy was compared with cefamandole plus amdinocillin in infants and children with suspected bacterial infections. Fifty-two infections in 50 patients with bone and joint (19 infections), pulmonary (19 infections), soft tissue (eight infections), and urinary tract (6 infections) diseases were treated. Bacterial infection was documented in 31 patients. All isolates were susceptible to cefamandole except one strain of Serratia marcescens, which was susceptible to the combination. In vitro synergy was demonstrated in all coliform bacilli, in three of seven Haemophilus strains, and in six of 16 gram-positive cocci. No correlation between degree of serum bactericidal activity and presence or absence of synergy could be demonstrated. One patient treated with cefamandole died; all other patients responded promptly to therapy without serious adverse drug effects.

Amdinocillin↗
PubMed1983

Ceftriaxone versus ampicillin and chloramphenicol for treatment of bacterial meningitis in children.

78 patients with bacterial meningitis were evaluated in a prospective, randomised study comparing twice-daily ceftriaxone as single-drug therapy with ampicillin and chloramphenicol given every 6 h. The groups were comparable in age, sex, days of illness before admission, and bacterial colony counts in cerebrospinal fluid (CSF). The pathogens were Haemophilus influenzae type b (54 cases), streptococci (9 cases), meningococci (9 cases), and unknown (6 cases). In 40 CSF specimens obtained 4-12 h after initiation of therapy, cultures were negative in 57% of the ceftriaxone patients and in 42% of the others. The mean falls in the CSF bacterial colony counts were 4.7 and 5.0 log10 colony-forming units/ml, respectively. Mean bactericidal activity in CSF was significantly greater in the ceftriaxone than in the conventional treatment group at the beginning and end of therapy. There were no significant differences in clinical responses or in frequency of complications, except for mild diarrhoea, which occurred in 16 ceftriaxone patients and in 8 in the other group (p less than 0.05).

Adolescent↗
PubMed1983

Fungal contamination in organ culture.

Fungal contamination of organ-cultured corneas was studied retrospectively. Over a 3 1/2-year period, 5.2% of 696 corneas became contaminated by fungi in organ culture. The average length of time for fungal contamination to occur in organ culture was 11 days. The most frequent contaminating fungi were those of the Candida species. In addition to previously identified risk factors for donor cornea contamination, those corneas from donors given mechanical respiratory assistance at the time of death, those corneas with long postmortem times, and those corneas with positive postwash cultures were identified as being at higher risk for fungal contamination in organ culture.

Cornea↗
PubMed1983

Cellulose acetate impressions of the ocular surface. Dry eye states.

Cellulose acetate impressions of the ocular surface were obtained for normal eyes, eyes with blepharoconjunctivitis, eyes with keratoconjunctivitis sicca, and eyes with primary ocular surface disease. Normal eyes and eyes with blepharoconjunctivitis had morphologically normal epithelium and goblet cells on the bulbar and palpebral ocular surfaces. Eyes with primary ocular surface disease had abnormal ocular surface impressions (decreased, abnormal, or absent goblet cells with abnormal epithelial cells) on both the bulbar and palpebral ocular surfaces. Conversely, eyes with keratoconjunctivitis sicca had substantial abnormalities of the epithelium and goblet cells only on the bulbar ocular surface, suggesting an environmental role in this disease process.

Adult↗
PubMed1983

Five v ten days' therapy with furazolidone for giardiasis.

In previous uncontrolled studies it has been reported that five days' treatment with furazolidone is effective for giardiasis. Efficacy of five v ten days of treatment was evaluated in a prospective, randomized study of 22 children with giardiasis. Eleven of 12 patients (92%) treated for ten days were cured based on clinical and parasitological response; one patient did not tolerate furazolidone and was treated with quinacrine hydrochloride. Only two of ten patients (20%) treated with a five-day regimen were cured. Of the other eight patients, five had prompt relapse of diarrhea after furazolidone treatment was stopped, diarrhea persisted in two, and diarrhea diminished but Giardia persisted in one. Six of eight patients in whom the five-day regimen failed were re-treated with furazolidone for ten days, and five patients were cured. Therapy with furazolidone for less than seven to ten days cannot be recommended for children with giardiasis.

Child, Preschool↗
PubMed1983

Rifampin prophylaxis v placebo for household contacts of children with Hemophilus influenzae type b disease.

The efficacy of rifampin prophylaxis (20 mg/kg/day in two doses for four days) in eliminating pharyngeal Hemophilus influenzae type b from household contacts of 38 patients with invasive Hemophilus disease was evaluated in a prospective, placebo-controlled fashion. At the end of treatment, rifampin efficacy was 91% in subjects younger than 5 years of age and 100% in those subjects older than 5 years. The H influenzae type b carrier rate of rifampin-treated subjects was significantly smaller than that of placebo-treated subjects one month after prophylaxis. However, 22% to 25% of rifampin-treated carriers younger than 5 years of age were colonized with H influenzae type b, based on cultures obtained one to four weeks after prophylaxis, while approximately 75% of placebo-treated carriers were still positive at this time.

Carrier State↗
PubMed1983

Anterior chamber lens subluxation through a basal peripheral iridectomy.

The superior supporting footplate of the Tennant-Anchor anterior chamber lens can subluxate through a basal peripheral iridectomy. In each of the three cases reported herein, the implant migrated superiorly along the ciliary body pars plana. In two cases, the lens implant was stabilized by adhesions of the superior supporting footplate to the ciliary body. In the third case, lens movement (pseudophakodonesis) caused the inferior lens footplate to rub against the corneal endothelium, producing secondary iridocyclitis and cystoid macular edema which required intraocular lens removal and exchange. This complication may be prevented by performing a mid-peripheral iridectomy or iridotomy rather than a large basal iridectomy.

Aged↗