Biomedical subjects

S Waheed

Publications and source records attributed to S Waheed.

7 recordsLinked to original sources

PubMed1998

New patterns of infecting organisms in late bleb-related endophthalmitis: a ten year review.

PURPOSE: To report the risk factors, causative organisms and visual outcomes in patients with late-onset bleb-related endophthalmitis. METHODS: Medical records of all patients with the clinical diagnosis of late-onset bleb-related endophthalmitis undergoing vitreous aspirates for culture at our institution from January 1987 to July 1996 were reviewed. Late-onset bleb-related endophthalmitis was defined as conjunctival injection, bleb purulence and intraocular inflammation developing at least 1 month following filtering surgery. RESULTS: Forty-nine cases of bleb-related endophthalmitis developed in 42 patients (23 men, 19 women). Mean patient age was 62.1 +/- 19.3 years (range 5-94 years). Thirty-nine patients underwent prior filtering surgery (superior trabeculectomy, 24 eyes; inferior trabeculectomy, 10 eyes; combined superior trabeculectomy/cataract extraction, 4 eyes; posterior lip sclerectomy, 1 eye) and 3 had inadvertent blebs following cataract extraction. Endophthalmitis developed an average of 25.4 +/- 23.5 months (range 1-96 months) post-operatively. Antifibrosis agents were used in 25 of 39 eyes undergoing filtering surgery (mitomycin C, 13 eyes; 5-fluorouracil, 12 eyes). Bleb leaks were documented in a total of 32 of 49 (65%) cases either before or at the time of endophthalmitis diagnosis. Vitreous cultures were positive in 42 of 49 (86%) cases. The most frequently cultured organisms were Staphylococcus aureus (13), Staphylococcus epidermidis (12), Streptococcus species (8) and Haemophilus influenzae (2). A final visual acuity of 20/400 or better was achieved in 32 of 49 (65%) cases. CONCLUSIONS: Staphylococcal species were the most frequently cultured organisms in this series and may be associated with better visual outcomes. Although a causal relationship cannot be established, these results suggest a strong association between bleb leaks and endophthalmitis.

Adolescent↗

PubMed1998

A unique case of Cryptococcus laurentii keratitis spread by a rigid gas permeable contact lens in a patient with onychomycosis.

PURPOSE: We report the first case of fungal keratitis caused by Cryptococcus laurentii, a nonneoformans species. METHODS: A case of C. laurentii keratitis in a diabetic, gas permeable contact lens wearer was diagnosed after microbiologic evaluation of the corneal button after emergent keratoplasty. The excised cornea was also culture positive for Staphylococcus aureus and Fusarium solani. The medical history was significant for onychomycosis of the right great toe 2 months previously. Cultures of the toenail and of the contact lens case were also positive for C. laurentii and F. solani. RESULTS: An initial penetrating keratoplasty with histopathologically clear margins was unsuccessful in preventing intraocular spread of the fungal infection. Despite a repeat limbus-to-limbus therapeutic keratoplasty, pars plana vitrectomy, multiple anterior chamber washouts, intravitreal antifungal injections, and systemic antifungal treatment, the eye was ultimately lost due to ongoing inflammation, ocular hypotony, and a total retinal detachment. Histopathologic examination of the enucleated eye demonstrated filamentous fungi but no yeast forms. CONCLUSIONS: C. laurentii, a nonneoformans species, should be included in the differential diagnosis of fungal keratitis. This unique case also demonstrates the importance of a thorough clinical history and proper contact lens hygiene, particularly in a diabetic patient.

Antifungal Agents↗

PubMed1998

Recurrent bleb infections.

AIM: To report the patient characteristics, causative organisms, and clinical outcomes in patients with recurrent bleb related ocular infections. METHODS: The medical records of all patients diagnosed with bleb related ocular infection at the New York Eye and Ear Infirmary over a 10 year period were reviewed. Recurrent bleb infection was defined as at least two episodes of bleb purulence with or without associated intraocular inflammation separated by a quiescent period of at least 3 months. RESULTS: Recurrent bleb infections developed in 12 eyes of 12 patients (10 men, two women) a mean of 16.3 (SD 17.9) months (range 3-51 months) after the initial infection. Two patients developed a third episode 3 and 20 months, respectively, after the second infection, yielding a total of 14 recurrent infection episodes. Recurrent infection developed after trabeculectomy in 11 eyes (adjunctive 5-fluorouracil, nine eyes; mitomycin C, one eye; no antifibrosis agent, one eye) and following cataract extraction with inadvertent bleb formation in one eye. Four (36.4%) of the filtered eyes had undergone trabeculectomy at the inferior limbus. The mean follow up time from filtering surgery to the first bleb related infection was 28 months for the nine patients treated with 5-fluorouracil and 14 months for the single patient treated with mitomycin C. 11 (78.6%) cases had a documented bleb leak in the 4 week period before or at the time of recurrent infection. Topical, prophylactic antibiotics had been used in 7/14 (50%) cases. The same organism was cultured from the initial and recurrent infections in 2/14 (14.3%) cases. CONCLUSION: Eyes that have been successfully treated for bleb related infection remain at risk for recurrent infection. No apparent correlation exists between organisms responsible for the initial and recurrent infections. The increased rate of recurrent bleb related infection in patients receiving adjunctive 5-fluorouracil compared to mitomycin C may have been related to the longer follow up of the 5-fluorouracil eyes.

Adult↗

PubMed1997

Bleb-related ocular infection in children after trabeculectomy with mitomycin C.

OBJECTIVE: The purpose of the study is to report the clinical course of bleb-related ocular infection in children after trabeculectomy with adjunctive mitomycin C. DESIGN: The study design was a retrospective review of all patients with a diagnosis of bleb-related ocular infection after trabeculectomy with adjunctive mitomycin C. PARTICIPANTS: Three children were identified in whom late postoperative bleb-related ocular infection developed. INTERVENTION: Treatment consisted of vitreous biopsy with intravitreous antibiotic and corticosteroid injection and/or bleb culture with topical and intravenous antibiotic administration. MAIN OUTCOME MEASURES: Visual acuity and intraocular pressure were measured. RESULTS: Bleb-related ocular infection developed an average of 16.7 +/- 10.9 months after trabeculectomy (range, 4-23 months). The mean age at presentation was 7.0 +/- 2.6 years (range, 4-10 years). Vitreous cultures were positive for staphylococci in two cases. A bleb culture from the third case also grew staphylococcus. All of the children recovered their initial vision after treatment of infection. However, one lost six lines of vision after a subsequent retinal detachment. Additional glaucoma surgery was required in one patient. CONCLUSIONS: Late bleb-related ocular infection may occur in children after trabeculectomy with mitomycin C and is characterized by abrupt onset, bleb infiltration, and rapid progression. Despite early preservation of vision after treatment of infection, significant late visual loss can occur.

Anti-Bacterial Agents↗

PubMed1993

N-terminal peptide fragments of lipocortin-1 inhibit A549 cell growth and block EGF-induced stimulation of proliferation.

Lipocortin-1 mediates growth inhibition of glucocorticoids in A549 cells by suppressing the release of PGE2 necessary for their proliferation. We now show that 2 peptide fragments derived from the N-terminal portion of lipocortin-1 corresponding to amino-acids 13-25 and 21-33 also inhibited A549 cell growth and suppressed release of PGE2, whereas peptides 1-12 and 13-25 (Phe21; in which the tyrosine at position 21 was replaced by a phenylalanine residue) were inactive. Similarly, peptide 21-33 (Phe21) and a scrambled sequence of 13-25 failed to inhibit cell growth. Moreover, the EGF-induced stimulation of cell proliferation and PGE2 release in these cells was blocked by peptides 13-25 and 21-33, and also by peptides 1-12, 13-25 (Phe21) and 21-33 (Phe21), but not by a scrambled sequence of peptide 13-25.

Adenocarcinoma↗

PubMed1992

Interleukin-1-inducible tumor growth arrest is characterized by activation of cell type-specific "early" gene expression programs.

Human melanoma cells, A375-C6, were "committed" to growth arrest within a few hours of exposure to interleukin-1 (IL-1). Co-treatment with actinomycin D rescued the cells from the "commitment," suggesting that "early" gene activation events may be crucial for growth arrest. To understand the mechanism of IL-1 action, we are studying early genes whose expression is induced by the cytokine. Five early genes associated with IL-1 action in the melanoma cells were isolated by differential screening of a cDNA library, which was enriched for sequences representing IL-1 responsive genes (IRGs). Nucleotide sequencing identified four of the genes as gro-alpha, gro-beta, c-jun and nur77/NGF1-B/NAK1, respectively, while the fifth was judged as novel by GenBank search and designated IRG-9. None of the early genes was uniquely associated with the antiproliferative action of IL-1: other growth-inhibitory as well as growth-stimulatory signals induced these genes in diverse cell types. However, analysis of the induction patterns of the IRGs and other well known early genes revealed that IL-1 action in the melanoma cells is characterized by activation of a unique primary gene expression program. This program was defined by the magnitude and temporal pattern of induction of the five IRGs, feeble induction of c-fos, and lack of induction of Egr-1 and c-myc. We present evidence that this program is growth arrest-specific in the melanoma cells and that distinct cell type-specific programs are associated with IL-1 growth-regulatory actions in other tumor cells. Based on these data, we propose that early genes may play multifunctional roles in tumor growth control, but specificity for the growth arrest action of IL-1 is determined by the composite early gene induction program.

Cell Division↗

PubMed1991

Antimitogenic and mitogenic actions of interleukin-1 in diverse cell types are associated with induction of gro gene expression.

Interleukin-1 (IL-1) is an antiproliferative factor for growing human melanoma A375-C6 cells. To define the molecular basis for the action of IL-1, we set out to identify early genes induced by the cytokine in the absence of de novo protein synthesis. cDNA libraries were constructed from A375-C6 cells that were exposed or unexposed to IL-1 plus cycloheximide. Subtractive hybridization was used to prepare a library that was enriched for IL-1-induced clones. Two of these clones were shown by Northern analysis to represent IL-1-inducible genes. Nucleotide sequencing identified these genes as gro/melanoma growth stimulatory activity, which encodes a cell secretory product, and c-jun, which encodes a transcription factor. IL-1 caused persistent steady state elevation of gro mRNA but only transient induction of c-jun. Northern analysis using gene probes for the transcription factors c-fos and Egr-1 revealed that IL-1 induced c-fos but not Egr-1 expression in these cells. This indicates that differential early gene expression characterizes the growth-inhibitory action of IL-1. In contrast, serum, which is mitogenic for these cells, induces c-jun, c-fos, and Egr-1, but not gro expression. These data imply that in A375-C6 cells, both growth-inhibitory and stimulatory signals can channel their action through c-fos and c-jun genes. As gro induction was specifically associated with the antimitogenic action of IL-1, we studied the effect of the cytokine on gro gene expression in other types of cells. IL-1 was mitogenic for human glioblastoma and monkey kidney epithelial cells and induced gro whereas other mitogens did not. Thus, IL-1 can induce gro gene expression in diverse cell types, whether it acts to stimulate or inhibit proliferation. Like other cytokines gro may play diverse cell-specific roles in growth control.

Animals↗