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J Chodosh

Publications and source records attributed to J Chodosh.

33 records · Page 2Linked to original sources
PubMed1997

Epithelial cell polarization is a determinant in the infectious outcome of immunoglobulin A-mediated entry by Epstein-Barr virus.

Diseases of the nasopharyngeal epithelium due to Epstein-Barr virus (EBV) infection typically occur in chronic virus carriers with preexisting virus-specific antibodies. In vitro studies have shown that EBV-specific immunoglobulin A (IgA) promotes infection of human epithelial cells, otherwise refractory to EBV, via the polymeric immunoglobulin receptor (pIgR). To determine if EBV similarly exploits IgA transport mechanisms in vivo, we examined the fate of IgA-EBV complexes in the blood of mice, where pIgR-mediated transcytosis of IgA immune complexes through hepatocytes eliminates exogenous antigens from the circulation. By PCR analysis we showed hepatobiliary transport of IgA-EBV in viremic mice, but without detectable hepatocellular infection by immunostaining. Because efficient transport of EBV immune complexes might avert an infectious outcome, we modulated the transcytotic pathway in polarized Madin-Darby canine kidney (MDCK) cells transfected with pIgR to determine the effect on viral antigen expression. Like hepatocytes in vivo, MDCK cells in polarized monolayers translocated IgA-EBV from the basal cell face into apical medium without evidence for infection. However, when exposed to IgA-EBV as unpolarized single-cell suspensions, MDCK cells expressed EBV immediate-early and early antigens. These results suggest that pIgR-mediated transcytosis of pIgA-EBV through epithelium facilitates endogenous spread of EBV in long-term virus carriers, with infection being confined to cells with altered polarity from prior cytopathology.

Animals↗
PubMed1996

Detection of Epstein-Barr virus genome in ocular tissues.

BACKGROUND: Epstein-Barr virus (EBV) is a ubiquitous mucosal pathogen with a propensity for lifelong, asymptomatic persistence. Because of reported association between EBV and ocular inflammatory disorders, we tested ocular tissues from normal eyes for presence of the EBV genome. METHODS: Ten freshly harvested cadaveric human eyes were dissected into limbal cornea, central cornea, aqueous humor, iris, vitreous humor, and optic nerve. Total cellular DNA preparations were screened for DNA sequences specific to EBV's large internal repeat region. After Southern transfer, polymerase chain reaction products were detected by a 32P-labeled oligonucleotide probe specific to amplified sequences internal to the polymerase chain reaction primers. RESULTS: Seven of ten eyes from deceased donors yielded a polymerase chain reaction product, indicating presence of EBV genome. In all, 12 (20%) of 60 cadaveric ocular samples contained EBV DNA. Only the optic nerve was consistently negative for EBV DNA. CONCLUSIONS: Detection of EBV DNA in cadaveric ocular tissues indicates a broad anatomic distribution of this persistent mucosal pathogen. The frequency with which EBV was found at apparently normal ocular sites raises the possibility for viral involvement in disease states, but emphasizes the need for specific criteria to implicate EBV in ocular pathology.

Cadaver↗
PubMed1996

Do admitted patients held in the emergency department impact the throughput of treat-and-release patients?

OBJECTIVE: To examine the impact of reducing ED "boarders" (through the use of a short-stay inpatient medicine unit) on the amount of time that treat-and-release patients spend in the ED. METHODS: A retrospective analysis of hours spent in the ED was made at a university hospital teaching ED for treat-and-release patients in 4 clinical categories: chest pain, asthma exacerbation, sickle-cell crisis, and seizure. The average hours per patient spent in the ED during the 4-month intervals before (August-November 1993) and after (August-November 1994) the establishment of the short-stay medicine unit were compared. Data were analyzed using the 2-tailed, unpaired t-test. RESULTS: This short-stay inpatient medicine unit received on average 135 patients per month from the ED, with an average length of stay of 2.4 days. The mean (+/-SD) number of admitted patients per day waiting in the ED > 8 hours for an inpatient bed dropped from 9.6 +/- 4.2., before the institution of this unit, to 2.3 +/- 2.6. There was a significant reduction in the average number of hours spent in the ED by treat-and-release patients with chest pain (from 7.3 +/- 6.0 to 5.5 +/- 4.8 hr/patient, p < 0.001) and asthma exacerbation (from 5.0 +/- 3.6 to 4.2 +/- 2.9 hr/patient, p < 0.05), but not with sickle-cell crisis or seizure, after the implementation of the short-stay unit. CONCLUSION: Reducing the number of admitted patients waiting in the ED for inpatients beds, in this case by establishment of a short-stay medicine unit, is associated with a decrease in the interval that treat-and-release patients spend in the ED.

Adult↗
PubMed1995

Adenovirus epithelial keratitis.

The authors sought to determine whether adenovirus could infect human corneal epithelium in vivo. They reviewed the medical records of six patients with adenovirus-positive viral corneal cultures who were examined at the Bascom Palmer Eye Institute between March 21, 1986, and December 31, 1992. The six patients with adenovirus-positive viral corneal cultures included one patient with dendritic epithelial keratitis, one with geographic epithelial ulceration, three with both geographic ulceration and contiguous dendrites, and one with heaped-up corneal epithelium but no ulceration. Four patients had rose bengal solution applied to their ocular surface, and in all four patients rose bengal uptake was seen at the epithelial edges of the dendrite or geographic ulceration in a manner characteristic of herpes simplex viral keratitis. Serotype determination of the isolates showed adenovirus type 3 (one patient), type 8 (three patients), type 19 (one patient), and indeterminate (one patient). Results of monoclonal antibody staining of cultures against herpes simplex virus (types 1 and 2) antigens was negative for all six cases. Adenovirus epithelial keratitis may result from infection of human corneal epithelium by the virus and rarely may mimic infection of corneal epithelium by herpes simplex virus.

Adenovirus Infections, Human↗
PubMed1994

A thymidine kinase deficient HSV-2 strain causes acute keratitis and establishes trigeminal ganglionic latency, but poorly reactivates in vivo.

The incidence of herpetic keratitis following intranasal or direct ocular infection with thymidine kinase-negative (TK-) strains of herpes simplex virus (HSV)-2 has not been well studied, and the role of the TK gene in the establishment of latency and virus reactivation is controversial. To determine whether a TK- strain of HSV-2 could establish trigeminal ganglionic latency and be reactivated in vivo to produce recurrent keratitis or nervous system infection, an animal model of acute and recurrent infection was utilized. Rabbits were infected by the intranasal or ocular routes, and latency was reactivated by immunosuppression. Virus shedding in nasal and ocular secretions was monitored, and the eyes were examined for the presence of corneal epithelial lesions during acute and reactivated infections. Central nervous system (CNS) and trigeminal ganglionic tissues were assayed by histologic, virologic, and in situ hybridization techniques. All rabbits intranasally infected shed virus in both ocular and nasal secretions, whereas only 30% of rabbits infected in the eyes shed virus in nasal secretions. Virus was recovered from cocultivation cultures, but not from cell-free homogenates, of trigeminal ganglionic and CNS tissues from animals inoculated by both routes. The incidence of keratitis was much greater after direct ocular inoculation, although both routes of inoculation produced CNS and ganglionic inflammatory lesions. Keratitis healed in 92% of the animals infected by the ocular route by 26 days post infection. Of rabbits initially infected in the eyes and then subjected to drug-induced reactivation, only 30% shed virus, which was limited to a 24 hour period; there was no reappearance of epithelial keratitis, no animal became blind, and none died. In contrast, latently infected control rabbits uniformly reactivated. These studies show that this TK-HSV-2 strain (i) replicates in the eye, (ii) is neuroinvasive but non-neurovirulent following intranasal and direct ocular infection; (iii) sheds in the eye more frequently and for longer periods after ocular than after intranasal inoculation; (iv) induces epithelial keratitis that usually heals spontaneously; (v) establishes latency in trigeminal ganglionic neurons, but no other ganglionic cells; and, (vi) reactivates in a small proportion of animals, but does not produce recurrent ocular lesions following drug-induced immunosuppression. Thus, the TK gene appears directly involved in HSV latency and reactivation in vivo.

Animals↗
PubMed1994

Staining characteristics and antiviral activity of sulforhodamine B and lissamine green B.

PURPOSE: Fluorescein and rose bengal are dyes used routinely in the examination of the ocular surface. As part of an ongoing search for a superior ophthalmic dye with optimal specificity and sensitivity and a lack of interference with subsequent viral cultures, and as part of studies that use chemical dyes to understand better the pathophysiology of ocular surface disorders, the staining characteristics and antiviral activity of sulforhodamine B and lissamine green B were investigated. METHODS: Staining of rabbit corneal epithelial cell cultures by sulforhodamine B and lissamine green B was compared to that of fluorescein and rose bengal. Diffusion of each dye through a collagen gel was measured. Uptake of lissamine green B by herpes simplex virus type 1 (HSV-1)-infected Vero cell cultures was compared at several times postinfection. The effect of sulforhodamine B and lissamine green B on HSV-1 plaque formation in Vero cells was determined. The cellular toxicity of sulforhodamine B and lissamine green B in vitro was examined by a quantitative 14C-amino acid uptake assay and by a qualitative cell viability assay. Finally, the effect of sulforhodamine B and lissamine green B on viral replication was compared in vivo with that of rose bengal in a rabbit model of herpetic epithelial keratitis. RESULTS: Rose bengal vividly stained cell monolayers of explant cultures of rabbit corneal epithelium. By light microscopy, sulforhodamine B and lissamine green B, like fluorescein, did not stain the epithelial cells, but did stain the corneal explant stroma. Pretreatment of epithelial cells with 0.25% trypsin for 5 minutes failed to induce dye uptake; however, pretreatment with 0.5% Triton X-100 for 5 minutes resulted in nuclear staining by lissamine green B, but not sulforhodamine B. When added to a collagen gel, the relative diffusion rate was fluorescein > lissamine green B > sulforhodamine B > rose bengal. By spectrophotometric analysis, HSV-1-infected and uninfected Vero cells bound equivalent amounts of lissamine green B until late in infection, when infected cells took up more dye (P < 0.001). A direct neutralization assay showed that 0.06% lissamine green B or 0.5% sulforhodamine B reduced HSV-1 plaque formation in Vero cells by greater than 50%, when present at the time of viral adsorption. By a quantitative 14C-amino acid uptake assay, lissamine green B was toxic to Vero cells in a dose-dependent manner, whereas sulforhodamine B was relatively nontoxic at the concentrations tested. By a cell viability assay, however, neither dye showed significant cellular toxicity. In a rabbit model of herpetic epithelial keratitis, rose bengal significantly reduced viral replication and recovery, whereas sulforhodamine B and lissamine green B had no effect. CONCLUSIONS: Neither sulforhodamine B nor lissamine green B stain healthy, normal cells. Lissamine green B stains membrane-damaged epithelial cells, but sulforhodamine B does not. Both sulforhodamine B and lissamine green B stain corneal stroma. Lissamine green B inhibits HSV-1 plaque formation at low concentrations of dye in vitro, which correlates with suppression of cellular metabolism as demonstrated by a 14C-amino acid uptake assay, but does not affect cell viability. Neither sulforhodamine B nor lissamine green B inhibit viral replication or recovery in vivo.

Animals↗
PubMed1992

Ophthalmomyiasis: a review with special reference to Cochliomyia hominivorax.

Ophthalmomyiasis, infestation of the eye by dipterous fly larvae, may result in sequelae ranging from minor irritation to blindness, disfigurement, and death. Infestation with Cochliomyia hominivorax, a medically significant and economically important species, exemplifies the mechanisms by which larvae can cause tissue damage. Although clinical history may be suggestive of ophthalmomyiasis, the definitive diagnosis requires direct observation of larvae. Treatment of ophthalmomyiasis involves removal or destruction of the larvae, if alive, and appropriate management of any sequelae. Preventive measures may not always be successful.

Animals↗
PubMed1992

Rose bengal inhibits herpes simplex virus replication in vero and human corneal epithelial cells in vitro.

Rose bengal dye is thought to highlight corneal lesions induced by herpes simplex virus type 1 (HSV-1) by virtue of its binding to dead or dying HSV-1-infected epithelial cells. However, whether rose bengal binds specifically to damaged versus normal corneal epithelial cells is unclear. To determine the binding properties of rose bengal, the authors compared binding of the dye to HSV-1-infected and uninfected cells, determined the cellular binding sites of the dye, and investigated the effects of rose bengal on HSV-1 replication in dye-treated cells in vitro. Spectrophotometric analysis revealed that uninfected and infected Vero cells bound equivalent amounts of dye at several times post inoculation, indicating that rose bengal does not preferentially bind to HSV-1-infected cells. By light microscopy, rose bengal was found to bind to the cell nuclei and perinuclear region of human corneal epithelial cells (HCEC) and Vero cells. Pretreatment of Vero and HCEC with different concentrations of rose bengal and exposure to 148 microW/cm2 of white light for 2 min reduced the ability of both cell types to support HSV-1 replication. Vero cells, in the absence of rose bengal, supported HSV-1 replication, whereas pre-treatment with 0.05% rose bengal reduced the yield of HSV-1 by 99.99% (P less than 0.000001) and 1% rose bengal completely prevented HSV replication. HCEC supported HSV-1 replication in the absence of rose bengal, but pre-treatment with 1% or 0.05% rose bengal completely prevented HSV-1 replication (P less than 0.000001).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMedDate not supplied

Comparative anatomy of mammalian conjunctival lymphoid tissue: a putative mucosal immune site.

Organized mucosa-associated lymphoid tissue (O-MALT) is defined by mucosal lymphoid follicles with unique overlying lymphoepithelia, and classically appears in tissues with a simple columnar epithelium. Within follicle-associated epithelium, goblet cells are characteristically absent, replaced by ultrastructurally distinct antigen-absorptive cells, termed M cells (or microfold cells) for the appearance of their apical cell membranes. To determine if mammalian conjunctiva, with its stratified squamous epithelium, can be considered as a site of O-MALT, we compared the light and electron microscopic anatomy of conjunctiva from fourteen species of non-human adult mammals, and the conjunctiva of human adults harvested at autopsy. Lymphoid follicles in the conjunctiva were demonstrated in all mammals studied except for mice and rats. In those mammals with conjunctival lymphoid follicles, the follicle-associated conjunctival epithelium was notable for an absence of goblet cells. Transmission electron microscopy demonstrated an intimate association of lymphocytes with surface epithelial cells, but epithelial cell morphology was uniform overlying the follicle, and other ultrastructural features of M cells were absent. Therefore, conjunctival lymphoid follicle-associated stratified squamous epithelium demonstrates some but not all features of O-MALT lymphoepithelia. Further studies are necessary to determine what role conjunctival lymphoid tissue may play in mucosal immunity.

Adult↗
PubMedDate not supplied

The use of DNA array technology in studies of ocular viral pathogenesis.

DNA arrays can be used to simultaneously analyze the expression of hundreds of genes and permit systematic approaches to biological discovery with a potentially profound impact on genomics, pharmacogenomics, and proteomics. Microarrays have been used to study host-pathogen interactions, and recently this technology has been applied to investigate host-virus interactions. DNA arrays are used to monitor host alterations in several virus-induced cancers and upon infection with wild-type or modified viruses, or viral gene products. Alternatively, viral chips are used to characterize the transcriptional program of pathogenic viruses and in antiviral drug screening and drug resistance. With an aim to extend the use of this technology to ocular research, and specifically to study changes in host cell transcription in ocular adenovirus infection, we used a commercial array to compare adenovirus-infected human corneal cells to mock-infected cells. Of the 1176 genes analyzed, 72 genes associated with cell cycle regulation, apoptosis, oncogenesis, transcription, signaling, and inflammation were differentially regulated. In this review we summarize the use of DNA arrays in the study of viral infections and suggest potential uses of the technology in ocular viral pathogenesis research.

Animals↗
PubMedDate not supplied

Partial dislocation of laser in situ keratomileusis flap by air bag injury.

PURPOSE: A patient developed significant corneal complications from air bag deployment, 17 months after laser in situ keratomileusis (LASIK). METHODS: Case report, slit-lamp microscopy, and review of the medical literature. RESULTS: A 37-year-old woman underwent bilateral LASIK with resultant 20/20 uncorrected visual acuity. Seventeen months later, she sustained facial and ocular injuries from air bag deployment during a motor vehicle accident. Examination revealed bilateral corneal abrasions, partial dislocation of the right corneal LASIK flap, and a hyphema in the right eye. The LASIK flap was realigned, but recovery was complicated by a slowly healing epithelial defect and flap edema. One month following the injury, epithelial ingrowth beneath the LASIK flap was noted. Surgical elevation of the flap and removal of the epithelial ingrowth was performed. Eight months later, epithelial ingrowth was absent and the visual acuity was 20/40. Residual irregular astigmatism necessitated rigid gas permeable contact lens fitting to achieve 20/20 visual acuity. CONCLUSIONS: Air bags may cause significant ocular trauma. The wound healing response of LASIK allows corneal flap separation from its stromal bed for an indeterminate time after surgery. Discussion of the possible risk of corneal trauma as part of informed consent prior to LASIK may be appropriate.

Accidents, Traffic↗